The study, led by Hiroto Ishiki of the Department of Palliative Medicine at the National Cancer Center Hospital in Tokyo and published in the journal Supportive Care in Cancer, examined a program the researchers call multimodal Japanese-style acupuncture and moxibustion, abbreviated MJAM. Unlike a single-technique acupuncture session, MJAM is a composite intervention that weaves together several distinct components: filiform needle acupuncture, in which fine needles are inserted into the skin; non-insertive needle therapy using a Teishin, a blunt instrument pressed against the skin without puncturing it; motion-style acupuncture, in which needling is combined with guided movement of the affected limb; indirect moxibustion, which applies the gentle heat of burning mugwort above the skin; hot pack application; and structured self-care instruction that patients continue at home.

The rationale for testing such a program rests on a substantial body of evidence suggesting that acupuncture can modulate chronic pain. Individual patient data meta-analyses have shown that acupuncture outperforms both sham procedures and usual care for chronic musculoskeletal pain, and systematic reviews have associated acupuncture and acupressure with improved cancer pain outcomes. Yet the picture for CIPN specifically has remained murky. Randomized trials of acupuncture for CIPN, including a large sham-controlled trial published in JAMA Network Open, have produced mixed results, and international guidelines from ASCO and ESMO currently offer few validated options for treating established CIPN, with duloxetine being one of the only pharmacological approaches supported by randomized evidence.

To explore whether the Japanese multimodal approach might help, the researchers conducted a single-center, single-arm study at the National Cancer Center Hospital. They enrolled women who had completed curative treatment for stage I to III breast cancer at least three months earlier and who were experiencing moderate to severe taxane-related CIPN pain, defined as a score of 4 or greater on item 5 of the Brief Pain Inventory, a validated instrument that asks patients to rate their average pain on a scale from 0 to 10. Between October 2022 and April 2024, 30 women with a median age of 58.0 years joined the study. On average, these patients were not fresh out of chemotherapy: the median time since completing treatment was 2.47 years, meaning their neuropathy had become a chronic, entrenched problem rather than a transient side effect.

Each participant received 12 weekly sessions of the standardized MJAM program, delivered over roughly three months. The researchers then tracked outcomes through week 16, four weeks after the final session, to see whether any benefit would persist beyond the treatment period itself. The primary endpoint was the change in the Brief Pain Inventory item 5 score, the patient’s rating of average pain, from baseline to week 16. At the start of the study, the mean baseline score was 5.3, with a standard deviation of 1.7, indicating that most participants were living with pain that was more than moderate on a daily basis.

The results showed a clear and statistically significant decline in pain over the course of the program. At week 4, after roughly a month of sessions, the mean change from baseline was only −0.1 points, a difference that could easily have arisen by chance, with a 95 percent confidence interval ranging from −0.6 to 0.3 and a p-value of 0.56. But by week 8, the mean reduction had grown to −0.7 points, a change that reached statistical significance. By week 12, the mean reduction was −1.1 points, and at the primary endpoint of week 16 it stood at −1.2 points, with a 90 percent confidence interval of −1.7 to −0.8 and a p-value below 0.0001. Notably, the benefit continued to accrue after the final session, suggesting that the effects of the program did not evaporate the moment treatment stopped.

The magnitude of the improvement matters as much as its statistical significance. In chronic pain research, the consensus recommendations from the IMMPACT initiative suggest that a reduction of roughly one point on a 0-to-10 pain scale can be clinically meaningful, and a drop of about 1.2 points on the Brief Pain Inventory average pain item approaches the thresholds often considered clinically important. For patients whose pain had persisted for more than two years after chemotherapy, a sustained reduction of this size, achieved without adding any new medication, represents a meaningful shift in daily comfort, even if it does not amount to a cure.

Safety and feasibility were equally central to the study’s conclusions. Twenty-eight of the 30 participants, or 93.3 percent, completed all 12 sessions, an adherence rate that speaks to the tolerability of the program and the practicality of weekly visits. Adverse events were uncommon and uniformly mild: nine participants, or 30.0 percent, experienced grade 1 events, the lowest severity category, with no serious harms reported. For a population of cancer survivors who are often wary of adding further interventions to their care, this safety profile is an important part of the story.

The researchers are careful to frame these findings as preliminary rather than definitive. Because the study was single-arm, with no control group, there is no way to rule out explanations such as the natural course of the condition, regression to the mean, or a strong placebo response, all of which are particularly relevant in pain research, where patient expectations can powerfully shape reported outcomes. The relatively small sample of 30 women and the single-center design further limit how far the results can be generalized. What the study does establish is that MJAM is safe, feasible, and associated with a reduction in pain severe enough to justify the confirmatory randomized clinical trial that the authors say is warranted.

Even so, the trial occupies an important position in a growing research landscape. Electroacupuncture trials for taxane-induced neuropathy are underway, pragmatic trials of acupuncture added to standard care have shown signals of benefit, and dose-response meta-analyses are beginning to explore how the timing and frequency of acupuncture sessions influence outcomes in CIPN. Integrative oncology guidelines from the Society for Integrative Oncology and ASCO already encourage the consideration of acupuncture for pain management in cancer care. If a rigorous randomized trial confirms what this exploratory study suggests, a centuries-old Japanese practice, refined with modern standardization and delivered alongside self-care education, could become a genuine option for the many breast cancer survivors whose nerve pain has, until now, had nowhere to go.

Subject of Research: Multimodal Japanese-style acupuncture and moxibustion as a treatment for taxane-related chemotherapy-induced peripheral neuropathy in breast cancer survivors

Article Title: Multimodal Japanese-style acupuncture and moxibustion for taxane-related chemotherapy-induced peripheral neuropathy in breast cancer survivors

Article References: Ishiki, H., Satomi, E., Matsuoka, H., Arakawa, S., Kawasaki, N., Horiguchi, Y., Takahashi, A., Takagi, T., Kobayashi, S., Oyamada, S., Ariyoshi, K., Kihara, K., Suto, A., Murata, T., & Takayama, S. (2026). Multimodal Japanese-style acupuncture and moxibustion for taxane-related chemotherapy-induced peripheral neuropathy in breast cancer survivors. Supportive Care in Cancer, 34(10), Article 997. https://doi.org/10.1007/s00520-026-11237-1

Image Credits: AI Generated

DOI: 10.1007/s00520-026-11237-1

Keywords: chemotherapy-induced peripheral neuropathy, breast cancer, acupuncture, moxibustion, taxanes, pain management, survivorship, integrative oncology, clinical trial, non-pharmacological therapy, Brief Pain Inventory, Japan

The new analysis, published in Annals of Gastroenterological Surgery, drew on data from 26 Japanese institutions affiliated with the Japan Society for Endoscopic Surgery, the Japan Society of Obstetrics and Gynecology, and the Japan Society of Endourology and Robotics, each of which had performed at least one robot-assisted pelvic exenteration for a pelvic malignancy. Between January 2012 and October 2022, 135 patients underwent pelvic exenteration for primary rectal cancer across these centers. Of these, 57 operations were performed laparoscopically, 35 were open procedures, and 43 were robot-assisted. The researchers, led by Shoma Yamamoto and colleagues, focused their secondary analysis on this robotic cohort, describing who was selected for the approach, how safely it was implemented, and how its use evolved over the decade of the study.

The patients chosen for robotic exenteration were, by any measure, facing advanced disease. Ninety-eight percent had clinical T4 tumors, meaning the cancer had grown directly into adjacent organs or structures. Seventy-nine percent had cancer that had spread to nearby lymph nodes, and 16 percent already had distant metastases at diagnosis, typically treated with neoadjuvant chemotherapy before surgery. The median age was 66 years, 84 percent were men, and nearly a quarter had an American Society of Anesthesiologists physical status score of 3 or higher, indicating severe systemic illness. Total pelvic exenteration, the most extensive variant involving removal of the rectum, distal colon, and all genitourinary viscera, accounted for 61 percent of the robotic cases, demonstrating that the robotic platform was not being reserved for the simpler, organ-preserving subtypes of the operation.

The perioperative results are the heart of the report. Among the 43 robotic patients, the median operative time was 690 minutes, nearly twelve hours on the table, underscoring the sheer complexity of the procedure. Yet the median intraoperative blood loss was just 360 milliliters, a striking figure for an operation of this magnitude. Only 30 percent of robotic patients required an intraoperative blood transfusion, and among those who did, the median transfused volume was a mere 280 milliliters. By comparison, in the open surgery cohort the median blood loss was 2,081 milliliters and 77 percent of patients needed transfusions. This matters clinically because perioperative transfusion has been linked in previous research to higher postoperative morbidity and worse long-term outcomes after colorectal cancer surgery, giving surgeons a concrete reason to favor techniques that minimize bleeding.

Oncological quality of the resection was equally impressive. Achieving an R0 resection, meaning complete removal of the tumor with no microscopic residual disease at the margins, is the single most important determinant of long-term survival after pelvic exenteration. In the robotic cohort, 42 of 43 patients, or 98 percent, achieved R0 resection, with only one patient left with microscopic residual tumor and none with gross residual disease. Within 30 days of surgery, complications of Clavien-Dindo Grade II or higher occurred in 37 percent of robotic patients, most commonly organ-space surgical site infections and ileus, each affecting five patients. More serious Grade III or higher complications arose in 16 percent. Crucially, not a single robotic patient required reoperation during hospitalization, and there were no deaths within 30 days of surgery. The median postoperative hospital stay was 23 days, notably shorter than the 34 days observed after both open and laparoscopic exenteration in the same cohort.

Perhaps the most telling finding is how rapidly the robotic approach took hold once it was introduced. The first robot-assisted pelvic exenteration in this cohort was performed in 2019, with five procedures that year, rising to six in 2020, thirteen in 2021, and nineteen by October 2022. By 2021 the robotic approach had become the most frequently used technique across the participating institutions, and in 2022 it accounted for 19 of the 26 pelvic exenterations performed, or 73 percent. The authors are careful to note that this rapid adoption should not be read as proof that the robot has replaced open or laparoscopic surgery, since shifts in patient selection, robotic platform availability, institutional experience, and referral patterns all influence which approach is chosen. Still, the trajectory reveals how quickly Japanese surgical centers integrated the technology into one of the most demanding operations they perform.

Why might the robot confer an advantage in the pelvis specifically? The surgical robot offers three-dimensional, magnified visualization of the operative field, articulated instruments with seven degrees of freedom that can far exceed the range of the human wrist, tremor filtration, motion scaling that converts large hand movements into precise micro-movements, and a stable endoscopic platform that eliminates camera shake. In the confined, bony confines of the pelvis, where the rectum sits amid the bladder, reproductive organs, major vessels, and the sacrum, these features may allow surgeons to dissect more precisely along tumor planes and secure hemostasis more effectively than is possible with conventional laparoscopic instruments. Previous studies have similarly reported lower blood loss with minimally invasive pelvic exenteration compared with open surgery, and the present findings are consistent with that pattern.

The authors are appropriately cautious about what these results do and do not prove. Because the study is retrospective and surgeons chose each patient’s approach based on tumor anatomy, technical feasibility, and institutional experience, the comparison between approaches is vulnerable to confounding by indication. Patients selected for robotic surgery may have had less extensive pelvic sidewall fixation, less fibrosis or inflammation, less vascular involvement, or lower reconstructive complexity than those directed to open surgery, and the study did not uniformly collect these anatomical details. Supplementary propensity score-matched analyses, which paired patients with similar measured characteristics, suggested favorable perioperative profiles for the robotic approach, but the researchers explicitly designated these analyses as exploratory and hypothesis-generating rather than definitive evidence of superiority. The high R0 rate, likewise, reflects successful resection in patients judged suitable for a minimally invasive attempt, not a demonstration that the robot outperforms the open approach oncologically.

The report also carries practical lessons for surgical programs considering the technology. Pelvic exenteration demands capabilities well beyond standard robot-assisted rectal resection: multivisceral dissection, urinary reconstruction, in this cohort 81 percent of robotic patients required ileal conduit diversion, intestinal reconstruction, complex intraoperative decision-making, and coordination across surgical specialties. Prior research suggests roughly 30 cases are needed to overcome the learning curve in routine robotic colorectal surgery, but exenteration is far more heterogeneous, and experience with standard procedures does not translate automatically. The authors recommend that robot-assisted exenteration be introduced cautiously at institutions with established expertise in both robotic surgery and open pelvic exenteration, supported by a mature perioperative care system.

The overall message is one of complementarity rather than replacement. Robot-assisted pelvic exenteration appears feasible and safe for selected patients with primary rectal cancer, offering dramatically reduced blood loss, a near-universal R0 rate, no 30-day mortality, and shorter hospital stays in this Japanese multicenter experience. Yet open surgery remains essential when wide exposure, rapid vascular control, extensive bony resection such as sacrectomy, severe pelvic sepsis, or major vascular involvement is anticipated; only six patients in the entire cohort, and just one robotic patient, underwent bony excision, so the most technically extreme cases remain largely outside the robotic experience. The operative approach, the authors conclude, should be individualized according to tumor anatomy, technical feasibility, and institutional capability. Longer follow-up will be needed to establish whether the encouraging short-term outcomes translate into superior survival, but for a procedure once considered the exclusive domain of open surgery, the robotic era has clearly arrived.

Subject of Research: Robot-assisted pelvic exenteration for primary rectal cancer

Article Title: Clinical Implementation and Perioperative Outcomes of Robot‐Assisted Pelvic Exenteration for Primary Rectal Cancer: A Multicenter Japanese Experience

Article References: Yamamoto, S., Kagawa, H., Yatabe, Y., & Kinugasa, Y. (2026). Clinical Implementation and Perioperative Outcomes of Robot‐Assisted Pelvic Exenteration for Primary Rectal Cancer: A Multicenter Japanese Experience. Annals of Gastroenterological Surgery, Article ags3.70296. https://doi.org/10.1002/ags3.70296

Image Credits: AI Generated

DOI: 10.1002/ags3.70296

Keywords: rectal cancer, pelvic exenteration, robotic surgery, minimally invasive surgery, R0 resection, surgical outcomes, Japan, multicenter study, T4 tumors, blood loss, perioperative complications, surgical oncology

Nakaya was born in 1900 and died in 1962, a lifespan that bracketed nearly every upheaval of twentieth-century Japan. He trained as a physicist, and it was at Hokkaido Imperial University, in the heart of Japan’s heavy-snowfall region, that he began the work for which he is still best known. Snow crystals were an obvious local phenomenon but a difficult experimental subject: natural snowflakes fall from clouds whose temperature and humidity conditions can only be guessed at, so relating a crystal’s final form to the conditions that produced it seemed almost impossible. Nakaya’s insight was to bring the cloud into the laboratory.

In 1936, after years of painstaking trial and error, Nakaya produced the world’s first artificial snow crystal in a cloud chamber. The achievement was more than a stunt. By systematically varying temperature and the degree of supersaturation of water vapor, he could grow crystals on demand and observe how their morphology changed. Needle-like crystals appeared in one regime, plates in another, and the celebrated branched dendrites in a third. The result was a compact summary of the dependence of snow crystal shape on the conditions of formation, a chart that has become known to atmospheric scientists everywhere as the Nakaya diagram. It remains a foundational reference for anyone studying how ice grows in clouds, and it underpins modern understanding of the microphysical processes that govern precipitation.

The artificial snowflake also carried a philosophical message that Nakaya would repeat throughout his writing career. He famously described snow crystals as letters sent from the sky, messages written in a hierarchy of characters, words and sentences that a patient observer could learn to read. The phrase captured his conviction that the laboratory and the sky were not separate realms: controlled experiments could decode what nature wrote, and the decoded message belonged to everyone, not just to specialists. That conviction would drive a second career that made him, in the words of his biographers, something like Japan’s answer to Carl Sagan.

The new study pays particular attention to two of Nakaya’s most ambitious magazine essays, which give the paper its title: World of the Black Moon and World of the White Moon. These were vivid first-person accounts of mid-twentieth-century scientific field expeditions, and they show Nakaya doing something that science communicators still strive for today, placing the reader inside the daily experience of research. World of the Black Moon drew on his travels to Hawaii, while World of the White Moon recounted his fieldwork in Greenland. Together they form a literary diary of an era when international geophysical science was expanding rapidly and when a Japanese writer could carry readers to places almost none of them would ever see.

The Greenland essays had particular weight, because Nakaya’s Greenland work was serious science as well as journalism. In the 1950s he began collaborating with the US Army’s Snow, Ice and Permafrost Research Establishment, known as SIPRE, investigating the physical properties of glacial ice. He took part in fieldwork in Greenland during the pioneering years of the deep ice coring project there, one of the earliest systematic attempts to read climate history out of layered polar ice. The cores recovered from the ice sheet in those years opened a new window on past climates, and Nakaya’s studies of ice deformation and crystal structure contributed to the young science of glaciology at a moment when its methods were still being invented.

Remarkably, World of the White Moon also contains a very early description, written for the general public, of the problem of anthropogenic climate change. At a time when the greenhouse effect was discussed almost exclusively in technical literature, Nakaya explained to magazine readers how human activity could alter the global climate, connecting his own observations of ice and snow to a planetary question. The biographers argue that this makes the essay a landmark in Japanese popular science writing, and it gives the piece an urgency that reads strikingly today, decades before climate communication became a global industry.

Nakaya’s literary range extended well beyond his own expeditions. He was a prolific essayist whose articles appeared regularly in Japanese magazines and were repeatedly collected into books, many of which remain in print more than sixty years after his death. His subjects ranged across science, culture and everyday life, and his tone was conversational rather than didactic. He treated his readers as intelligent companions rather than students, an approach that earned him a broad and loyal audience. The new study samples a handful of these articles to convey the scope and flavor of the oeuvre, and the picture that emerges is of a writer who saw no boundary between the laboratory bench and the literary page.

He was equally inventive in another medium. Nakaya was a pioneer of educational documentary filmmaking in Japan, and he played an instrumental role in the formation of a major Japanese film studio. For a scientist of his generation, moving into cinema was an unusual and forward-looking choice, and it reflected the same instinct that powered his essays: that the public understanding of science required new forms, new audiences and new technologies of storytelling. His films brought the behavior of snow and ice to viewers who would never read a physics journal, extending the reach of his science far beyond the university.

Hamilton and Ohfuchi also situate Nakaya’s life in its Japanese cultural context and in the dramatic history of his era, which was shadowed by the Second World War. The war interrupted scientific collaboration across the Pacific and reshaped the institutions within which Nakaya worked, and the biography does not shy away from these difficulties. What survives the retelling is the coherence of the man’s project. Whether growing a snow crystal in a cloud chamber, drilling into Greenland ice with American colleagues, writing an essay about a Hawaiian expedition or producing a documentary film, Nakaya pursued a single goal: to make the physical world legible, and to make that legibility a shared public good. The new study, written for his 125th birthday year, introduces his life and achievements to an international audience that, until now, has known him mainly through a single elegant diagram and a handful of snowflakes made by hand.

Subject of Research: The life, snow crystal physics, glaciology and popular science writing of Japanese physicist Ukichiro Nakaya

Article Title: The Remarkable Scientist and Writer Ukichiro Nakaya and his "Black Moon" and "White Moon" Worlds

Article References: The Remarkable Scientist and Writer Ukichiro Nakaya and his "Black Moon" and "White Moon" Worlds. (n.d.). https://doi.org/10.5194/hgss-2026-12

Image Credits: AI Generated

DOI: 10.5194/hgss-2026-12

Keywords: Ukichiro Nakaya, snow crystals, Nakaya diagram, cloud chamber, glaciology, Greenland ice coring, popular science, science communication, history of science, Japan, climate change, documentary film

The program in question is the Japanese Surgeons as Educators course, known as JSaE, which was established as a national faculty development initiative to promote structured surgical teaching across Japan. The course runs in two stages, a Basic course followed by an Advanced course, and it has already demonstrated positive educational outcomes in earlier evaluations. Its architects, however, recognized a gap that has been documented across medical education research: even well-designed faculty development initiatives require reinforcement if participants are to retain what they learned and, crucially, implement it in the daily environment of a busy hospital. A systematic review of faculty development initiatives designed to enhance teaching effectiveness, updated as BEME Guide 40, has underscored that one-off workshops rarely produce durable change without follow-up. The JSaE team set out to discover precisely what kind of follow-up their alumni would actually use.

To do this, the researchers conducted a nationwide, cross-sectional survey of JSaE alumni who had completed both the Basic and Advanced courses between May 2023 and February 2025. They distributed an anonymous online questionnaire through the official JSaE alumni mailing list, using the SurveyMonkey platform. The instrument was deliberately practical: it asked about interest in a refresher course, the motivations behind that interest, preferred delivery formats and venues, and the curricular topics that alumni considered highest priority. Responses were analyzed descriptively using item-specific denominators, a methodological choice that keeps each percentage tied honestly to the number of people who actually answered that particular question rather than inflating precision with assumptions about missing data.

The response rate alone makes the findings noteworthy. Of 147 eligible alumni, 109 responded, yielding a 74 percent response rate, a figure that many survey-based studies in medical education would envy. Most respondents were staff surgeons, and gastrointestinal surgery emerged as the most represented specialty, which reflects the demographic weight of that field within Japanese surgical departments. The headline number, though, was the level of demand: 98 of 107 respondents to that item, or 92 percent, expressed interest in attending a refresher course. For a program still in its early phase of national rollout, that is an emphatic endorsement from the very people who have already invested time in completing both course levels.

Why would surgeons who have already finished an intensive two-stage program want to return for more? The survey ranked the motivations, and the leading one was reinforcement of previously acquired knowledge. This aligns closely with what learning science would predict. Ericsson’s work on deliberate practice has argued that the acquisition and, just as importantly, the maintenance of expert performance in medicine requires ongoing, structured engagement rather than a single exposure. Cognitive load theory, developed by Sweller, adds another layer of explanation: complex teaching frameworks, such as models for briefing, intraoperative teaching, and debriefing in the operating room, impose significant mental demands, and without periodic rehearsal the cognitive structures supporting them weaken. The second-ranked motivation, learning updated educational practices, reflects a recognition that the field itself moves. Assessment tools, feedback techniques, and simulation-based methods evolve, and surgeons who teach want to stay current.

The preferences for format and venue reveal a shrewd understanding of how working clinicians actually budget their time. The most popular delivery format was a pre-course workshop linked to an academic society meeting, rather than a standalone event requiring separate travel. When asked where such a refresher should be held, respondents pointed to the annual congress of the Japanese Association for Surgical Education, followed by the Japan Surgical Society and the Japanese Society of Gastroenterological Surgery. This society-linked model solves two problems at once. It reduces the logistical burden of attending yet another meeting in an already crowded professional calendar, and it embeds faculty development within the communities of practice where surgical educators already exchange ideas. Previous needs assessment work by the same research group, both within Japan and across six global regions, has highlighted that surgical trainees and educators face persistent barriers of time and access, making integration into existing gatherings a rational design choice.

On content, the alumni were equally decisive. The highest-priority topics were Assessment of Surgical Performance, Feedback Techniques, and Teaching Surgical Skills. Notably, these priorities align with the core JSaE frameworks already taught in the Basic and Advanced courses, which suggests that alumni are not asking for a fundamentally new curriculum but for deeper, refreshed engagement with the same foundations. The emphasis on assessment echoes findings from the United States, where a study in the American Journal of Surgery defined a pressing need for faculty development specifically in assessment, noting that surgeons are often asked to judge trainee performance without formal training in how to do so reliably. Feedback techniques rank similarly high internationally, since giving effective feedback is among the most consequential and most poorly supported tasks in surgical training.

The broader context in Japan makes this work more than an internal program evaluation. Recent nationwide questionnaire surveys of graduating surgical trainees have documented the current state of the Japanese surgical training system, including facility-based disparities in satisfaction and working conditions across university hospitals, community hospitals, and hybrid-type facilities. Against that backdrop, the quality of teaching that trainees receive is a national concern, not a local one. The establishment of the Japanese Association for Surgical Education itself grew out of an effort to promote systematic surgical education in the country, and the JSaE course represents one of its most concrete instruments. A scoping review of surgical curriculum renewal processes published in Perspectives on Medical Education in 2025 emphasized that successful curriculum change depends on structured needs assessment before redesign, which is exactly the methodological step this survey provides for the program’s next phase.

The study’s authors, led by Akihiko Oshita of Onomichi General Hospital with collaborators spanning institutions from Hokkaido University in Sapporo to the University of Iowa in the United States, conclude that JSaE alumni demonstrated strong demand for a longitudinal, society-linked refresher course. They describe the alignment between the priority topics and the existing core frameworks as a practical foundation for the next phase of national surgical faculty development in Japan. The phrase longitudinal deserves emphasis: the design being contemplated is not another isolated workshop but a continuing relationship between the program and its graduates, delivered at intervals and anchored to the annual meetings where Japanese surgical education already convenes. That model mirrors the Kirkpatrick framework for evaluating training programs, which treats lasting behavioral change in the workplace, rather than immediate satisfaction, as the meaningful endpoint of any educational intervention.

For the international readership of surgical education, the survey offers a template as much as a finding. Needs assessments in continuing professional development have been the subject of their own scoping review, which noted that learning needs assessments are most valuable when they directly shape program design rather than serving as ritual data collection. Here the connection is explicit: 92 percent demand, a named preferred format, three named host societies, and three ranked topics constitute an actionable specification. If the JSaE refresher course proceeds on these terms, Japan will be testing whether society-embedded, reinforcement-based faculty development can close the implementation gap that has long separated what surgeons learn about teaching from what they actually do in the operating room. The results of that experiment will be watched well beyond Japan’s borders, because every country with a surgical workforce struggles with the same quiet problem: teachers trained once, then left to improvise.

Subject of Research: A nationwide needs assessment survey of Japanese surgical faculty development alumni to inform the design of a refresher course for the Surgeons as Educators program

Article Title: Designing the next phase of the Japanese surgeons as educators course: a nationwide needs assessment survey of alumni

Article References: Oshita, A., Poudel, S., Suzuki, A., Imai, K., Takami, H., Kimura, T., Shikama, A., Homma, T., Hida, K., Isobe, M., & Hoshi, H. (2026). Designing the next phase of the Japanese surgeons as educators course: a nationwide needs assessment survey of alumni. Global Surgical Education – Journal of the Association for Surgical Education, 5(1), Article 189. https://doi.org/10.1007/s44186-026-00597-1

Image Credits: AI Generated

DOI: 10.1007/s44186-026-00597-1

Keywords: surgical education, faculty development, Japan, needs assessment, refresher course, surgeons as educators, continuing professional development, assessment of surgical performance, feedback techniques, teaching surgical skills, academic societies, survey research

The story begins with two stickleback species. Freshwater threespine sticklebacks, Gasterosteus aculeatus, live permanently in the rivers of the region, while the Japan Sea stickleback, Gasterosteus nipponicus, is a marine or sea-run migrant. The two lineages diverged roughly 680,000 years ago and have evolved strong but incomplete reproductive isolation. The tsunami appears to have carried marine G. nipponicus inland from the Pacific Ocean, while the backwash swept freshwater G. aculeatus down from upstream reaches, dumping both species into the same newly formed ponds. By 2012, researchers sampling the ponds found a population teeming with hybrids, something that had never been documented in Otsuchi before the disaster.

What happened next is the heart of the new study, published in Nature Ecology & Evolution. Using restriction-site associated DNA sequencing across nine years of sampling, the team tracked the fate of G. nipponicus ancestry generation by generation. In 2012, 38 percent of sampled fish were hybrids, most of them first-generation backcrosses toward G. aculeatus. Yet by 2020, within roughly ten generations, the population had become almost entirely pure G. aculeatus. The marine species’ genome had been swept out of the population with remarkable speed, a process the researchers describe as genome-wide purging.

Could this rapid loss of foreign alleles simply be a statistical accident of small population size? The researchers tested that possibility rigorously. A mark–recapture survey estimated the census population at 22,485 individuals, and stochastic simulations based on the Wright–Fisher model were run at effective population sizes corresponding to 100 percent, 10 percent and 1 percent of that figure. Starting from the observed allele frequencies at 667 species-diagnostic loci, the simulations showed that at most loci—98.7 percent, 97.8 percent and 85.3 percent respectively—the real population purged G. nipponicus alleles faster than drift alone could ever explain. Selection, not chance, was doing the work.

The next question was where that selection was strongest. The team already knew from previous work that the two species are kept apart by multiple barriers: ecological selection against immigrants and hybrids, differences in habitat choice, sexual isolation and hybrid male sterility. Quantitative trait locus mapping had previously tied sexual isolation and hybrid male sterility to chromosomes 9 and 19, which function as the neo-X and ancestral-X chromosomes in G. nipponicus, a system that arose through a Y–autosome fusion. Strikingly, the new time-series data showed that G. nipponicus alleles at these major reproductive isolation loci vanished within the first few generations, faster than the genomic background.

To understand why, the researchers ran field experiments in the tsunami-created habitat itself. In outdoor net enclosures, pure G. nipponicus suffered dramatically higher mortality than pure G. aculeatus, with backcross hybrids showing intermediate survival. By comparing allele frequencies between the backcross fish released into the enclosure and the survivors six months later, the team identified five candidate loci on chromosomes 10, 15, 17 and 20 and the ancestral X chromosome where marine alleles reduced survival. Interestingly, a well-known freshwater adaptation—an extra copy of the fatty acid desaturase gene Fads2 on chromosome 12—played no role here, likely because prey organisms washed in from the sea kept the ponds well supplied with docosahexaenoic acid.

Habitat choice added a second, equally elegant mechanism. Because the tsunami ponds connect to the estuary only through small tunnels, any fish carrying marine alleles that triggered seaward migration would simply leave, never to return. The researchers built an eight-chambered experimental stream system in the field and found that G. nipponicus migrated seaward far more often than freshwater G. aculeatus, with backcross hybrids again intermediate. Quantitative trait locus mapping revealed significant loci for seaward migration on chromosome 10 and the ancestral X chromosome—regions that overlapped with the survival loci. This clustering of barriers for multiple isolating mechanisms on the same chromosomes, including a large-X effect, means a handful of genomic regions act as a disproportionately powerful barrier to gene flow.

But major loci alone could not explain the full story. Once the deleterious alleles at major barrier loci are purged in the first few generations, no further selection should act on neutral introgressed DNA elsewhere in the genome. Individual-based simulations confirmed this: models with only major reproductive isolation loci, or with drift alone, failed to reproduce both the observed admixture pattern and the subsequent genome-wide purging. The pattern only emerged when the team added many pairs of type 2 Dobzhansky–Muller incompatibilities—negative epistatic interactions between a dominant allele of one species and a recessive allele of the other—scattered across the genome. These incompatibilities do not harm first-generation hybrids but inflict fitness costs on later generations, when alleles become homozygous. In other words, a dense genome-wide network of weak incompatibilities, combined with a few major barriers, appears to be what prevents species fusion.

The pattern repeated itself elsewhere. The team located two other tsunami-struck stickleback habitats, in Iwaizumi and Kuji, roughly 55 and 90 kilometers north of Otsuchi. Both contained recent hybrids with predominantly G. aculeatus ancestry, and the frequencies of G. nipponicus-derived alleles across the genome correlated significantly between habitats, suggesting that the same genomic regions were purged first in each independently founded population. Differences in how much marine ancestry remained appeared to depend on the initial ancestry composition, with simulations showing that higher initial frequencies of G. nipponicus led to greater retention of its alleles. Elevated marine ancestry on chromosomes 12 and 13 in Iwaizumi may reflect heterozygote advantage or adaptive introgression, though the current data cannot rule out drift.

The implications reach well beyond Japanese ponds. The divergence between these two species sits near a proposed transitional threshold of speciation, and the study provides direct evidence that species identity can persist even after extensive introgression, provided enough genetic incompatibilities have accumulated. It also echoes a lesson Darwin drew from an earthquake in Chile aboard the Beagle: catastrophic geological events can open rare windows onto fundamental evolutionary processes. As climate change intensifies natural disasters and human activity increasingly forces species into contact, predicting whether hybridization leads to fusion, extinction or renewed isolation becomes ever more urgent. This nine-year experiment, launched by a tragedy, shows that the genome keeps its own defenses—and that watching them work is now possible in real time.

Subject of Research: Real-time genomic purging of introgressed alleles in a tsunami-induced hybrid stickleback population

Article Title: Rapid genome-wide purging following tsunami-induced hybridization in a stickleback population

Article References: Hosoki, T. K., Mori, S., Kagawa, K., Nishida, S., Kume, M., Nagano, A. J., Kanbe, H., Kakioka, R., Nakamoto, K., Iino, Y., Kodama, M., Oba, S., Seong, T., Kabeya, N., Ishikawa, A., Yoshida, K., Yamasaki, Y. Y., & Kitano, J. (2026). Rapid genome-wide purging following tsunami-induced hybridization in a stickleback population. Nature Ecology & Evolution. https://doi.org/10.1038/s41559-026-03184-1

Image Credits: AI Generated

DOI: 10.1038/s41559-026-03184-1

Keywords: stickleback, hybridization, speciation, genomics, tsunami, introgression, reproductive isolation, Dobzhansky-Muller incompatibilities, purging, evolutionary biology, population genetics, Japan

The study was led by Suzuna Shiomizu of the Health Promotion Division of Kasugai City Hall, working with colleagues at Hiroshima University and Nagoya University Graduate School of Medicine. The team drew on data from 4,840 participants, including 3,290 men and 1,550 women, who underwent health examinations at the Seirei Preventive Health Center in Japan. The participants ranged in age from 35 to 69 years, with a median age of 53. As part of the broader Japan Multi-Institutional Collaborative Cohort, known as J-MICC, this population offered researchers a rare opportunity to examine lifestyle behaviors in fine detail among a large, well-characterized group of working-age and older adults.

To measure meal timing regularity, the researchers used a self-administered questionnaire that asked participants whether their meals occurred at consistent times across four separate dimensions: weekday lunch, weekday dinner, weekend lunch, and weekend dinner. Each dimension was categorized simply as regular or irregular. The oral health behaviors under scrutiny were equally concrete. Participants reported how often they brushed their teeth, whether they used interdental cleaning devices such as floss or interdental brushes, and whether they received professional dental cleanings. These three behaviors form the backbone of standard preventive dentistry recommendations worldwide, including guidance from the World Health Organization on oral disease prevention.

The raw numbers revealed that outright irregular meal timing was relatively uncommon in this health-conscious population. Only 1.8 percent of participants reported irregular weekday lunches, 1.4 percent reported irregular weekday dinners, 2.2 percent reported irregular weekend lunches, and just 0.9 percent reported irregular weekend dinners. That scarcity makes the associations that emerged all the more striking. Even a small group of people with erratic eating schedules showed a markedly different pattern of oral care, hinting that meal timing may act as a sensitive marker for broader lifestyle stability.

Using multivariable-adjusted logistic regression, a statistical technique that estimates the odds of an outcome while accounting for other influencing factors, the researchers found that irregular weekday dinner timing was associated with brushing less than twice daily, with an odds ratio of 2.05 and a 95 percent confidence interval of 1.19 to 3.54. Irregular weekend lunch carried an even stronger signal, with an odds ratio of 2.28 and a confidence interval of 1.45 to 3.57, while irregular weekend dinner showed an odds ratio of 2.09 with a confidence interval of 1.07 to 4.08. In practical terms, people whose meals drifted across the calendar were about twice as likely to fall short of the twice-daily brushing benchmark that dentists consider a minimum standard.

The link extended beyond brushing, though in a more fragile form. Irregular weekend dinner timing was also associated with less frequent use of interdental cleaning devices, showing an odds ratio of 2.25 with a confidence interval of 1.02 to 4.96. However, when the researchers applied their full statistical adjustment, the associations involving weekend dinner, both for tooth brushing and for interdental cleaning, were attenuated and no longer reached statistical significance. The connections between weekday dinner and weekend lunch irregularity and tooth brushing frequency, by contrast, remained robust even after full adjustment. Notably, no significant relationship was found between meal timing regularity and professional dental cleaning, suggesting that irregular eaters do not necessarily skip the dentist; they simply falter in the small, daily rituals that happen at home.

Why would the timing of meals and the habit of brushing teeth travel together? The authors propose that regular meal timing may serve as a marker of stable daily routines more generally. A person who eats lunch at noon every day, including lazy Sunday afternoons, likely organizes the rest of life around predictable anchors as well. Tooth brushing is what behavioral scientists call a habit cued by context: it is triggered by waking, by finishing a meal, and by going to bed. When meals float unpredictably, those cues weaken, and the automatic chain of events that ends with a toothbrush in hand can break down. Weekend patterns may matter especially because weekday schedules are often enforced by work, while weekends expose the true flexibility, or fragility, of a person’s routine.

There is also a plausible biological pathway worth considering. Dental caries and periodontal disease both depend on the frequency and timing of sugar and food exposure in the mouth. Each eating episode lowers oral pH and feeds acid-producing bacteria, so erratic eating can mean more frequent acid challenges to enamel. If irregular eaters also brush less often, the two effects could compound, leaving teeth exposed to acid for longer stretches with less mechanical removal of plaque. The new study did not measure dental outcomes directly, so this compounding remains a hypothesis, but it aligns with established models of how caries develop and why dentists emphasize both brushing frequency and the spacing of meals and snacks.

The researchers are careful about what the data can and cannot show. Because the study is cross-sectional, capturing a single snapshot in time, it cannot establish whether irregular meal timing causes poor oral hygiene or whether both simply spring from a common root, such as lower conscientiousness, shift work, psychological stress, or disrupted circadian rhythms. Reverse causation is also conceivable: someone with painful dental problems might abandon regular meals, though the modest prevalence of irregular timing makes this less likely to drive the whole signal. The authors explicitly state that causal inference is not possible from this design, and the attenuation of some associations after full adjustment underscores the need for caution when interpreting the weaker findings.

Even with those caveats, the study opens an intriguing public health avenue. Oral diseases remain among the most common chronic conditions globally, and simple, scalable markers that identify people at risk of neglecting daily hygiene could sharpen prevention efforts. If meal timing regularity proves to be such a marker in longitudinal and intervention studies, a single question about weekend eating habits could flag patients who need extra encouragement toward twice-daily brushing and interdental cleaning. For the rest of us, the message is refreshingly mundane: keeping breakfast, lunch, and dinner anchored to the same hours, even on Saturdays and Sundays, may quietly reinforce the small habits that keep teeth and gums healthy for decades. The clock, it turns out, may be an unsung ally of the toothbrush.

Subject of Research: The association between meal timing regularity and oral health behaviors in Japanese adults

Article Title: Association between meal timing regularity and oral health behaviors

Article References: Shiomizu, S., Mitsui, M., Furuie, A., Wei, H., Matsuo, K., Asaeda, M., Kurawaki, Y., Nishimura, R., Nagayoshi, M., Tamura, T., Wakai, K., & Naito, M. (2026). Association between meal timing regularity and oral health behaviors. BMC Public Health. https://doi.org/10.1186/s12889-026-29820-w

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29820-w

Keywords: meal timing regularity, oral health behaviors, tooth brushing frequency, interdental cleaning, professional dental cleaning, cross-sectional study, BMC Public Health, chrononutrition, public health, preventive dentistry, J-MICC cohort, Japan

The research, published in the journal Plant and Soil by Shogo Imada and Masaru Nagai of the Institute for Environmental Sciences in Rokkasho and their colleague Hideki Kakiuchi of the institute’s Tritium Research Center, set out to test a deceptively simple idea. If natural tritium concentrations in soil water show a clear vertical pattern near the surface, then the tritium signature of water inside tree branches could reveal which soil layers the trees have been tapping. Between the summers and autumns of 2023 and 2024, the team collected soil cores and branch samples from overstory trees at study sites in northeastern Japan, working with three species that dominate humid temperate forests of the region: the deciduous oak Quercus crispula and two pines, Pinus densiflora and Pinus thunbergii.

Tritium is the radioactive heavy isotope of hydrogen, and in the environment it exists overwhelmingly in the form of tritiated water, chemically indistinguishable from ordinary H2O. It is produced naturally in the upper atmosphere by cosmic ray interactions and has also been released by atmospheric nuclear weapons testing in the mid-twentieth century and by nuclear facilities. Because tritium is part of the water molecule itself, it moves with water through soil and plants without the complications that affect other tracers. Unlike the stable isotopes deuterium and oxygen-18, tritium does not undergo significant fractionation during most biological processes, meaning its concentration in xylem water should faithfully reflect the mixture of soil water sources a tree has absorbed. That property makes it an attractive candidate for tracing water movement through the soil-plant-atmosphere continuum.

The technical challenge is that natural tritium concentrations in today’s environment are extremely low, decades after the peak of bomb testing. To measure them, the researchers extracted water from soil and branch samples using cryogenic vacuum extraction, a technique in which samples are frozen and then heated under vacuum so that the water sublimates and condenses in a cold trap. Previous work has shown that this extraction method barely alters low-level tritium concentrations in the free water of environmental samples, which was a critical prerequisite for the study. The extracted water was then subjected to electrolytic enrichment, a process that concentrates tritiated water molecules relative to ordinary water by preferentially electrolyzing the lighter isotopologues, before the enriched samples were counted with liquid scintillation techniques to determine tritium activity.

The results were striking. At both study sites, the team observed clear vertical gradients in soil water tritium concentrations within the uppermost soil layers, within the top 10 centimeters at one site and the top 20 centimeters at the other. The gradients were not random. Tritium concentrations generally increased toward the soil surface as soil moisture decreased within these depth ranges, a pattern that points to evaporative enrichment as the likely mechanism. When water evaporates from the soil surface, remaining water becomes progressively enriched in heavier water molecules, including tritiated water, much as a drying puddle becomes saltier at its edges. The researchers suggest that this evaporation-driven process shapes a tritium profile steep enough to serve as a usable depth marker even in the isotopically homogenized soils of humid temperate climates.

With a usable soil profile in hand, the team turned to the trees. Tritium concentrations measured in the xylem water of the oak and pine branches closely matched those of soil water at depths shallower than 25 centimeters. That correspondence implies that the overstory trees at these sites were drawing the bulk of their water from the near-surface soil layers during the study periods. The finding is notable because it runs counter to the common assumption that large forest trees necessarily rely on deep water sources. Other studies in temperate hardwood forests have similarly found substantial reliance on shallow soil water, and the new tritium evidence adds an independent line of support in an environment where the conventional stable isotope approach struggles.

The broader context makes the result more than a methodological curiosity. Understanding the water uptake depth of forest trees is central to predicting how forests will respond to drought, how species coexist by partitioning belowground resources, and how water moves from soil through vegetation back to the atmosphere. Transpiration by plants is a major flux in the global water cycle, and models of land-atmosphere exchange depend on assumptions about rooting depth and water source that are difficult to verify. Global syntheses of tree water uptake patterns have revealed enormous variation across biomes, but humid temperate forests remain underrepresented, precisely because the standard tools fail there. A tracer that works where stable isotopes do not could fill a significant gap in the map of global vegetation hydrology.

Tritium has, of course, a long history in hydrology, where its radioactive half-life of about 12.3 years made it invaluable for dating young groundwater and tracing recharge in the era of bomb-era tritium fallout. Its application to plant water sourcing has been far rarer, partly because of the analytical difficulty of measuring the very low concentrations found in today’s precipitation and soils. The Japanese team’s demonstration that electrolytic enrichment combined with cryogenic extraction can resolve meaningful gradients in soil water and match them to xylem signatures suggests that the technique could be adopted more widely, particularly in regions with monitoring infrastructure for environmental tritium. The authors note that distinct vertical gradients in natural tritium can occur in near-surface soil water in humid temperate forests and may provide useful information for inferring tree water uptake depths, a conclusion that opens the door to comparative studies across sites and seasons.

Cautions remain. The study covered two growing seasons at sites in northeastern Japan, and the observed gradients depended on evaporative enrichment, which may weaken under prolonged wet weather or differ across soil textures. The researchers also note that interactions between tritiated water and soil minerals, such as adsorption and exchange in clay-rich horizons, could complicate profiles in some settings, although such effects appear limited in the near-surface layers examined here. Seasonal variation in precipitation tritium inputs adds another layer of variability that future work will need to quantify. Still, the study demonstrates that a tracer once valued mainly for tracking fallout and groundwater age can be repurposed to answer one of ecology’s most persistent hidden questions: how deep the roots of a forest actually reach. As climate change intensifies drought stress in even the wettest temperate forests, knowing where trees drink may prove essential to forecasting which forests endure and which fade.

Subject of Research: Use of natural tritium as a tracer to estimate the water uptake depth of trees in humid temperate forests

Article Title: Effectiveness of the use of natural tritium as a tracer to estimate the water uptake depth of humid temperate trees

Article References: Imada, S., Nagai, M., & Kakiuchi, H. (2026). Effectiveness of the use of natural tritium as a tracer to estimate the water uptake depth of humid temperate trees. Plant and Soil. https://doi.org/10.1007/s11104-026-09089-z

Image Credits: AI Generated

DOI: 10.1007/s11104-026-09089-z

Keywords: tritium, water uptake depth, humid temperate forest, soil water isotopes, xylem water, cryogenic vacuum extraction, electrolytic enrichment, evaporative enrichment, root water uptake, forest ecology, Japan, Plant and Soil

Coastal dunes are among the most threatened ecosystems on Earth, squeezed between rising seas, intensifying erosion, tourism, and urban expansion. What makes them ecologically remarkable is their strict spatial order. Moving inland from the waterline, plants sort themselves into zones: an unfixed zone of shifting sand nearest the shore, a semi-fixed zone behind it, and finally a fixed zone of stabilized dune where the most sensitive species live. Because each zone depends on precise gradients of salt spray, sand movement, wind, and soil conditions, the fixed zone is the first casualty of development and the hardest to restore. Its loss ripples through the entire system, taking rare plants with it.

The research team, led by Yuki Yamanaka, Keiko Nagashima, and Yasutaka Nakata, focused on Juniperus conferta, a low-growing shrubby juniper that serves as the classic indicator species of the fixed dune zone across Hokkaido, Honshu, Shikoku, Kyushu, and Sakhalin. The species is listed as rare in ten Japanese prefectures and grows alongside threatened plants such as Viola grayi and Veronica ornata. The logic of the study is elegant: if you can map precisely where J. conferta survives and characterize the microtopographic conditions it requires, you gain a practical yardstick for identifying the remaining strongholds of the fixed zone, and by extension, the habitats of the rare species that depend on it.

The historical half of the analysis is sobering. Using an 1898 topographic map, United States military aerial photographs from 1947, and a 2009 aerial survey, the researchers built land-cover maps for three time slices and tracked what happened to the original dune surface. In 1898, sand dunes covered roughly 192 hectares, the largest dune area in Kyoto Prefecture. By 1947 that figure had fallen to about 106 hectares, and by 2009 only about 33 hectares remained, a decline of more than 80 percent in little over a century. Afforestation, which began in the Edo period to control drifting sand and accelerated during Japan’s postwar economic boom, accounted for roughly half of the original dune area by 2009, while urbanization and paddy fields consumed much of the rest.

The losses were strikingly uneven across the dune’s four sectors. In the west, the dune shrank to about a fifth of its original extent as forests and town expanded inland. The west-central sector suffered the steepest transformation, with approximately 80 percent of its 1898 dunes replaced by conifer plantations. The east fared worst of all: around 90 percent of its original sand dunes had been converted to other land uses by 2009, with wastelands mapped in 1947 largely becoming urban areas. Only the east-central sector, a rocky coastline where steep cliffs limited development, retained nearly all of its original sandy habitat, a quirk of geology that would prove decisive for the study’s rarest plants.

To capture the present-day physical template of the dune, the team deployed a drone equipped with LiDAR, a laser instrument that fires pulses at the ground and records the returning light to build a dense three-dimensional point cloud. From this they derived a digital terrain model at one-meter resolution, matching the scale of their vegetation quadrats, along with slope angle, curvature, distance from the shoreline, and elevation. Crucially, they also computed the difference between the 2024 drone-derived terrain model and a 2009 airborne LiDAR dataset, producing a map of elevation change across fifteen years. After correcting a systematic vertical offset of about 3.46 meters in the drone data using fifty stable reference points, they established a conservative detection limit of roughly 0.12 meters, meaning only elevation changes beyond that threshold were treated as real.

On the ground, the researchers surveyed 165 one-square-meter quadrats distributed randomly across the four sectors and classified the vegetation into seven communities using the Two-Way Indicator Species Analysis, a standard clustering technique for presence-absence data. The J. conferta community split into two ecologically distinct groups: one on sandy beach coasts and one on rocky coasts. In total, the surveys recorded 30 coastal dune species and 40 non-coastal species, including eight listed in the Kyoto Prefecture Red Data Book. The east-central rocky sector stood out with the highest species richness at 47 species and five rare species, while the heavily modified west sector contained no rare species at all and a relatively high proportion of alien plants.

The statistical core of the study used generalized linear models to ask which topographic variables best predict where each J. conferta community occurs. For the sandy-beach community, two factors emerged consistently: the probability of occurrence rose with increasing distance from the shoreline and with greater elevation change since 2009. This makes intuitive sense. The community’s stronghold in the west-central sector is the one place where the beach is wide enough, over 100 meters, for the full sequence of dune zones to develop, allowing pioneer communities to trap drifting sand and build the stable backshore that dwarf juniper shrubland requires. The rocky-coast community told a different story: models pointed toward shorter distances from the shoreline and higher elevation, but a sensitivity analysis accounting for spatial autocorrelation in the data weakened these effects, suggesting the pattern may reflect broader geomorphic processes, such as a history of coastal erosion, rather than simple topographic rules.

Bringing the two lines of evidence together, the study delivers a sector-by-sector diagnosis. The west-central area, despite pine plantations, still supports functioning zonation and a resident J. conferta community, though afforestation has opened the door to invasive species. The east-central rocky coast harbors the greatest concentration of rare plants, including Viola grayi and Veronica ornata growing symbiotically with the juniper, but it is also the sector showing net elevation loss, a signature of active erosion. Because plant roots stabilize rocky slopes, the researchers warn that erosion there could accelerate, leaving the rare fixed-zone communities perched precariously at the cliff edge. The west and east sectors have effectively lost their fixed zones altogether, one to plantations and alien invasions, the other to direct human modification of the dune surface.

The authors are careful about the limits of their framework. Soil salinity, moisture, nutrients, and grain size, all known drivers of dune vegetation, were not directly measured, so the model coefficients describe associations with topography rather than isolated causes. The historical and LiDAR analyses address different time scales and should be read as complementary rather than causally linked, and the findings from a single Sea of Japan dune may not transfer to coasts with different tides, winds, and climates. Even so, the message is powerful and portable: a single well-chosen indicator species, read through the lens of drone-borne laser scanning and archival maps, can pinpoint which parts of a degraded landscape still hold conservation value and which restoration efforts are most urgent. As coastal dunes continue to retreat worldwide under the combined pressure of stabilization plantings, urban growth, and tourism, that kind of quantitative, repeatable diagnosis may be the difference between documenting an extinction and preventing one.

Subject of Research: Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography

Article Title: Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography

Article References: Yamanaka, Y., Nagashima, K., & Nakata, Y. (2026). Indicator-based assessment of coastal dune ecosystem degradation using historical land-cover change and UAV-LiDAR microtopography. Environmental and Sustainability Indicators, 32, Article 101548. https://doi.org/10.1016/j.indic.2026.101548

Image Credits: AI Generated

DOI: 10.1016/j.indic.2026.101548

Keywords: coastal dunes, Juniperus conferta, UAV-LiDAR, land-cover change, ecosystem degradation, vegetation zonation, Kumihama Dune, rare species, digital terrain model, coastal erosion, conservation indicators, Japan

The scale of the underlying field effort is remarkable. Between 2013 and 2025, members of the Hokkaido University Tick Hunting Team, joined by collaborators across the country, systematically dragged cloth flags through vegetation at 1,018 sites spanning 38 of Japan’s 47 prefectures. This flagging method, the standard technique for sampling host-seeking ticks, involves pulling a white cloth square across low vegetation so that questing ticks latch onto it. The surveys yielded a total of 22,416 individual ticks, representing the sixteen species that formed the basis of the modeling work. Because tick distribution data have historically been restricted to localized studies, this dataset provides an unusually broad and consistent foundation for predicting where each species can persist across the entire Japanese archipelago.

To transform field observations into predictive maps, the team employed the maximum entropy method, widely known as Maxent, a machine-learning approach that estimates the probability of species presence from occurrence records and environmental variables. The models incorporated three categories of predictors: climatic variables such as temperature and precipitation, topographic features such as elevation, and landscape variables describing land cover and habitat type. The resulting predictions were generated at a resolution of one square kilometer, fine enough to distinguish habitat suitability between neighboring valleys or forest patches. Model performance was robust across the sixteen species, giving the researchers confidence that the maps capture genuine ecological patterns rather than statistical noise.

Among all the environmental variables tested, one emerged with unexpected prominence: snow depth. For six of the sixteen tick species, snow depth contributed the largest share of explanatory power in the models. This finding carries real ecological weight. Deep, persistent snow insulates the ground layer where ticks overwinter, moderating the extreme cold that would otherwise kill them, but it also shapes the length of the active season and the structure of the vegetation communities ticks depend on. In a country that stretches from subtropical Okinawa to the frigid northern island of Hokkaido, snow depth turns out to be a fundamental determinant of where ticks can establish populations, and by extension, where the pathogens they carry can circulate.

The predicted suitable habitats showed striking interspecific variation, following both latitudinal and elevational gradients. Some species are confined to the cool, snowy north, while others thrive in the warmer south; some occupy lowland forests, others climb into mountain terrain. This diversity of distribution patterns matters because each tick species is a competent vector for a different set of pathogens. A map that lumps all ticks together would obscure precisely the spatial structure that determines which diseases threaten which communities. The new species-by-species approach reveals that patchwork in detail for the first time.

The most consequential step of the analysis went beyond mapping habitats and asked whether the predicted distributions actually explain where human cases of tick-borne disease occur. The researchers converted their one-kilometer probability maps into prefecture-level statistics, calculating for each of Japan’s prefectures the proportion of grid cells predicted to be occupied by each tick species. They then used regression analyses to test whether these occupancy proportions could account for the reported numbers of five notifiable tick-borne diseases: severe fever with thrombocytopenia syndrome, tick-borne encephalitis, Japanese spotted fever, Lyme disease, and relapsing fever. The answer was a clear yes, with significant correlations between the predicted area occupied by suspected vector species and the reported case counts for each disease.

The species-disease alignments were biologically coherent in ways that strengthen confidence in the results. For diseases with a predominantly northern distribution, such as Lyme disease, the predicted distributions of Ixodes pavlovskyi and Ixodes persulcatus aligned closely with reported case occurrence, and both species are known vectors of the Borrelia bacteria that cause the illness. At the opposite end of the map, Haemaphysalis flava emerged as the primary contributor to model performance for Japanese spotted fever and the secondary contributor for severe fever with thrombocytopenia syndrome, two diseases concentrated in southern and western Japan. Again, the correlated species are recognized vectors of the corresponding pathogens. In other words, the models did not merely find statistical associations; they recovered the known vector ecology of each disease from environmental data alone.

This external validation against disease surveillance data is what elevates the study from a biogeographic exercise to a practical public health tool. Species distribution models are often evaluated solely on their ability to reproduce the occurrence records used to build them, which risks circularity. By demonstrating that independently collected human disease reports track the predicted tick distributions, the researchers provided evidence that the maps capture something real about transmission risk on the ground. For public health authorities, this means the maps can serve as an early-warning layer, highlighting prefectures where environmental conditions favor vector species even before cases accumulate.

The implications extend beyond Japan’s borders. Climate change is expected to shift temperature and snowfall patterns across temperate Asia, and because snow depth proved to be such a powerful predictor, changes in snow cover could redraw the boundaries of tick habitat in the coming decades. Species currently confined to Hokkaido’s snowy forests might expand southward or upslope, carrying tick-borne encephalitis and other northern diseases into new territories. Conversely, warming could compress the suitable habitat of cold-adapted species. The modeling framework established in this study, with its one-kilometer resolution and multi-species coverage, provides a baseline against which such shifts can be measured and anticipated.

The study also demonstrates the value of sustained, collaborative fieldwork. Twelve years of surveys, involving dozens of students and researchers in the Hokkaido University Tick Hunting Team and partner laboratories from Kitasato University, the University of Tokyo, the University of Osaka, and beyond, produced the occurrence data that no amount of modeling ingenuity could substitute for. The authors note that the resulting maps, offering a nationwide overview of tick distributions, serve as basic information for anticipating the occurrence of tick-borne diseases in the region. For clinicians, the maps offer context for differential diagnosis when patients present with fever after outdoor exposure; for epidemiologists, they provide a spatial framework for surveillance prioritization; and for the public, they offer a clearer picture of the invisible landscape of risk that accompanies a walk through Japan’s forests and grasslands.

Subject of Research: Species distribution modeling of tick vectors and tick-borne disease occurrence in Japan

Article Title: Predicting the distribution of 16 tick species in Japan and its association with the occurrence of tick-borne diseases

Article References: Ito, M., Ohari, Y., Ohsugi, Y., Taya, Y., Hayashi, N., Ogata, S., Kusakisako, K., Qiu, Y., Nonaka, N., Mizuma, K., Torii, S., Kajihara, M., Hokkaido University Tick Hunting Team (HUT-HuT), Mimura, Y., Regilme, M. A. F., Thu, M. J., Kovba, A., Kwak, M., Teo, E., … Nakao, R. (2026). Predicting the distribution of 16 tick species in Japan and its association with the occurrence of tick-borne diseases. Parasites & Vectors. https://doi.org/10.1186/s13071-026-07717-2

Image Credits: AI Generated

DOI: 10.1186/s13071-026-07717-2

Keywords: ticks, species distribution modeling, Maxent, Japan, Lyme disease, severe fever with thrombocytopenia syndrome, Japanese spotted fever, tick-borne encephalitis, snow depth, vector ecology, public health, Ixodes

Andrew Subica, a professor of social medicine, population, and public health in the UC Riverside School of Medicine, and Shinichi Nagata, an associate professor at the University of Tsukuba, surveyed 1,012 Japanese adults using a geographically representative national online sample. Rather than treating stigma as a single attitude, the researchers broke it into several measurable dimensions: perceptions of how serious and how treatable mental illness is, beliefs about its causes, judgments about perceived dangerousness, and desired social distance from people living with mental disorders. This multidimensional approach matters because different components of stigma can operate independently, and interventions that target one component may leave others untouched.

To place the Japanese data in comparative context, the team compared their results with nationally representative data from the United States drawn from the 2018 General Social Survey, a long-running instrument that tracks American attitudes and behaviors. The comparison revealed a striking treatment gap. Only about 54 percent of Japanese participants reported being willing to seek mental health treatment for serious emotional problems, compared with roughly 70 percent of U.S. participants. Willingness to seek care is a critical behavioral indicator, because even in health systems with abundant clinical resources, treatment that is never requested is treatment that is never delivered.

The social distance findings were even more pronounced. About 84 percent of Japanese participants said they would want to socially distance themselves from people with depression, compared with about 28 percent of U.S. participants. Yet the pattern did not extend to every dimension of stigma. Japanese participants were actually less likely than Americans to view individuals with mental disorders as dangerous. This dissociation between perceived dangerousness and desired social distance is analytically important: it suggests that in Japan, stigma operates less through fear of violence and more through a broader relational withdrawal, a preference for separation that may reflect norms around family reputation, social standing, and the historical concealment of mental illness from public view.

Beliefs about treatability diverged as well. For major depression, about 78 percent of Japanese participants believed treatment would help, compared with approximately 95 percent of U.S. participants. Japanese respondents were also more likely to believe that mental disorders would improve without treatment. These beliefs are not trivial. Expectations about treatability are among the strongest predictors of whether people convert distress into help-seeking behavior, and the belief that problems will resolve on their own can function as a cognitive substitute for clinical care, particularly in cultures where acknowledging psychological suffering carries social cost.

Subica argued that the cross-cultural variation carries a direct lesson for public health practice. In the United States, anti-stigma campaigns have frequently concentrated on correcting the perception that people with mental illness are dangerous, an emphasis grounded in decades of American survey research. The Japanese data suggest that reducing social distance, rather than defusing perceived dangerousness, may be the more relevant target there. Mental health stigma, the study indicates, can take different forms across cultures and nations, and an intervention validated in one country cannot simply be transplanted to another with the assumption that it will work equivalently somewhere else.

The most unexpected result concerned a psychological construct known as mattering, the belief that one is important to and cared about by others. Subica and Nagata found that a stronger sense of mattering was associated with greater willingness to seek treatment in Japan, even within a highly stigmatizing environment. Prior treatment experience and stronger beliefs that mental illness can improve with treatment were also associated with greater willingness to seek care, while a greater desire for social distance and the belief that disorders would improve without treatment were associated with lower willingness. The prominence of mattering surprised the researchers themselves; they had not anticipated such a strong connection between the construct and treatment seeking.

Subica was careful to note the limits of the finding. The study does not establish that increasing people’s sense of mattering will cause them to seek treatment; the data are cross-sectional and associational. Nevertheless, he said, the result provides a basis for further research into social connection and mattering as potentially modifiable factors in promoting treatment engagement. If subsequent experimental or longitudinal work confirms the pathway, mattering could become a practical lever for interventions, one that operates not by changing attitudes toward mental illness in the abstract but by strengthening the interpersonal bonds that make help-seeking feel safe and worthwhile.

The cultural context underlying these numbers is essential to interpreting them. Subica explained that mental illness has historically been hidden from public view in Japan, and that concerns about family reputation and social standing can shape how mental illness is perceived and disclosed. In some cultures, he noted, mental illness is not seen simply as something that affects one person; it can be seen as something that affects the family’s status and reputation. That framing helps explain why desired social distance is so elevated even while perceived dangerousness is comparatively low: the stigma is relational and reputational rather than fear-based, woven into expectations about how individuals and families present themselves to their communities.

For Subica, the research also carries a personal dimension. His mother is Japanese, and he had not returned to Japan for many years before beginning this work. His broader research program has consistently shown that the culture and communities people live in strongly shape both mental and physical health outcomes in the United States, and he wanted to understand whether similar cultural factors were at play in Japan and what could be learned about helping people overcome barriers to care. The study’s central lesson, he said, is that culture matters: researchers and practitioners need to understand the specific cultural factors affecting stigma and treatment seeking and design interventions around those factors, rather than assuming that strategies developed elsewhere will translate. Amid Japan’s ongoing mental health crisis, the survey offers both a diagnosis of the treatment gap and a starting point for closing it.

Subject of Research: Mental illness stigma and treatment-seeking willingness among Japanese adults

Article Title: Mental health stigma in Japan may deter care

Article References: Mental health stigma in Japan may deter care. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: mental health stigma, Japan, social distance, treatment-seeking, mattering, cross-cultural comparison, depression, public health, General Social Survey, anti-stigma interventions, health equity, survey research