Gesture imitation performance in community-dwelling older people: assessment of a gesture imitation task in the screening and diagnosis of mild cognitive impairment and dementia.

BACKGROUND: Gesture imitation, a simple tool for assessing visuospatial/visuoconstructive functions, is reportedly useful for screening and diagnosing dementia. However, gesture imitation performance in healthy older adults is largely unknown, as are the factors associated with lower performance. To address these unknowns, we examined the gesture imitation performance of a large number of community-dwelling older adults aged ≥65 years in Arao City, Kumamoto Prefecture (southern Japan). METHODS: The examiner presented the participants with eight gesture patterns and considered it a success if they could imitate them within 10 s. The success rate of each gesture imitation was calculated for three diagnostic groups: cognitively normal (CN) (n = 1184), mild cognitive impairment (MCI) (n = 237), and dementia (n = 47). Next, we reorganised the original gesture imitation battery by combining six selected gestures with the following scoring method: if the participants successfully imitated the gestures, immediately or within 5 s, two points were assigned. If they succeeded within 5-10 s, one point was assigned. The sensitivity and specificity of the battery were investigated to detect the dementia and MCI groups. Factors associated with gesture imitation battery scores were examined. RESULTS: Except one complex gesture, the success rate of imitation in the CN group was high, approximately 90%. The sensitivity and specificity of the gesture imitation battery for discriminating between the dementia and CN groups and between the MCI and CN groups were 70%/88%, and 45%/75%, respectively. Ageing, male sex, and a diagnosis of dementia or MCI were associated with lower scores on the gesture imitation battery. CONCLUSION: Gesture imitation tasks alone may not be sufficient to detect MCI. However, by combining gestures with set time limits, gesture imitation tasks can be a low-burden and effective method for detecting dementia, even in community medicine, such as during health check-ups.

Plant Gall Diversity in Burned Semi-natural Grasslands in Japan.

We surveyed woody plants, including oaks and chestnuts (Quercus L. and Castanea Mill.), and recorded the inhabiting galls induced by oak gall wasps (Hymenoptera: Cynipidae: Cynipini) at seven Japanese semi-natural grassland sites maintained by traditional regular burning with two of the seven abandoned grassland areas. Woody plants were established in all burned and abandoned grasslands. Oak species were found at four of the seven sites. In total, 15 types of cynipid galls were recorded at all four sites where oak species were found. However, the occurrence of species was site-specific for host trees and cynipid galls. Although a few ecological studies of oak gall wasps inhabiting grassland environments, which have rapidly decreased in recent decades, have been conducted, this study suggests that semi-natural grasslands may be potential habitats for oak gall wasps and their host trees, and we provide a checklist of oak gall wasps with host oak records in semi-natural grasslands throughout Japan.

The trajectory of non-depressed suicidal ideation in community-dwelling older people in a rural area in Japan: a prospective longitudinal study with a 3-year follow-up.

BACKGROUND: Suicidal ideation is closely related to severe suicidal behaviour and is an important predictor of suicide attempt and completion, including in older people. Older people tend to have many opportunities to be conscious of death, and may have vague suicidal ideation because of various loss experiences, even if they are not depressed. We hypothesised that suicidal ideation among older people might be a risk factor for later transition to depression. The present study aimed to clarify risk factors that predict the incidence of depression in older people 3 years post-baseline in a rural area of Japan, and to examine the subsequent course of depression among non-depressed older people with suicidal ideation. METHODS: In 2015 and 2018, survey questionnaires were mailed to residents aged 65 years and over living in a rural area in Japan. Participants were divided into a depression group and a non-depression group using 15-item Geriatric Depression Scale scores 3 years post-baseline. Logistic regression analysis was used to identify predictive factors of late-life depression 3 years post-baseline. RESULTS: We received 597 valid responses, with a 3-year follow-up rate of 78.8%. Regarding suicidal ideation, 6.7% of non-depressed older people exhibited suicidal ideation at baseline. Of these, 9.8% exhibited depression after 3 years post-baseline. Logistic regression analysis indicated that development of late-life depression is significantly associated with suicidal ideation, being female, and poor health-related quality of life (HRQOL). CONCLUSIONS: The results revealed that suicidal ideation, being female, and poor HRQOL were predictive factors of the development of late-life depression 3 years post-baseline in a rural area of Japan. These findings provide novel information regarding the transition to depression among community-dwelling older people who are not depressed but have suicidal ideation. Whereas suicidal ideation is considered to be a symptom of depression, the current results suggest that suicidal ideation may precede depression in some older people.

Comparison of caregiver burden between dementia with Lewy bodies and Alzheimer's disease.

BACKGROUND: Caring for patients with dementia with Lewy bodies (DLB) would be more stressful for their caregivers than those with Alzheimer's disease (AD). In this study, we compared levels of caregiver burden and the possible influential factors on the caregiver burden between DLB and AD. METHODS: Ninety-three DLB patients and 500 AD patients were selected from the Kumamoto University Dementia Registry. Caregiver burden, neuropsychiatric symptoms, basic activities of daily living (BADL) and instrumental activities of daily living (IADL) were assessed by the Japanese version of the Zarit Caregiver Burden Interview (J-ZBI), the Neuropsychiatric Inventory (NPI), the Physical Self-Maintenance Scale (PSMS), and the Lawton IADL scale, respectively. RESULTS: Despite the comparable Mini-Mental State Examination score, the J-ZBI score was significantly higher in the DLB group than the AD group (P = 0.012). A stepwise multiple regression analysis revealed that IADL score (ß = -0.23, P = 0.049), PSMS score (ß = -0.31, P = 0.010), disinhibition (ß = 0.22, P = 0.008), and anxiety (ß = 0.19, P = 0.027) were significantly associated with J-ZBI score in DLB. In AD, caregiver's relationship with patient (child) (ß = 0.104, P = 0.005), caregiver's gender (female) (ß = 0.106, P = 0.004), IADL score (ß = -0.237, P < 0.001), irritability (ß = 0.183, P < 0.001), apathy (ß = 0.132, P = 0.001), agitation (ß = 0.118, P = 0.007), and aberrant motor behaviour (ß = 0.107, P = 0.010) were associated with caregiver burden. CONCLUSIONS: Caring for DLB patients caused a higher degree of caregiver burden than AD patients in the same level of cognitive decline. The factors responsible for the caregiver's burden were different between DLB and AD. The caregiver burden for DLB patients was associated with the disability of basic ADL, IADL impairment, anxiety and disinhibition.

Relationship between preoperative anxiety and onset of delirium after cardiovascular surgery in elderly patients: focus on personality and coping process.

BACKGROUND: Postoperative delirium is associated with increased mortality. Therefore, it is important to manage delirium during the entire perioperative period. Preoperative anxiety is associated with poor prognosis in postoperative patients who have undergone cardiovascular surgery. This study aims to investigate the relationship between preoperative anxiety and onset of delirium after cardiovascular surgery in elderly patients (aged 65 years or older), considering the individual psychological characteristics, such as personality and stress coping skills in response to anxiety, as confounding factors. METHODS: This prospective study included patients aged >65 years in a preoperative state before undergoing cardiovascular surgery. Subjects were divided into two groups based on whether they experienced postoperative delirium, or not. We compared clinical and demographic factors, preoperative psychiatric and psychological factors, and intraoperative and perioperative physical factors between the control and delirium groups. Multiple imputations were used to account for missing data. RESULTS: Out of 168 subjects enrolled in this study, 26 (15.5%) developed postoperative delirium. Univariate analysis showed significant differences in age (P = 0.027), cognitive function (P = 0.007), agreeableness (P = 0.029), and the Acute Physiology and Chronic Health Evaluation-II (APACHE-II) score (P = 0.023) between the delirium and control groups. Multiple logistic regression analysis did not identify a significant association between preoperative anxiety and the onset of postoperative delirium. However, age (odds ratio (OR) = 1.114, P = 0.018), agreeableness (OR = 0.555, P = 0.008), and the APACHE-II score (OR = 1.227, P = 0.008) were identified as risk factors for postoperative delirium. CONCLUSION: Agreeableness, one of the personality traits associated with preoperative anxiety, appears to be involved in the development of postoperative delirium as an independent psychological factor, regardless of age or physical factors.

Disconnection between conservation awareness and outcome: Identifying a bottleneck on non-native species introduction via footwear.

Unintentional seed introduction mediated by visitor's clothing and footwear is a major source of biological invasion into natural areas. To effectively avert these unintentional introductions, we must understand the links that connect relevant knowledge and desired outcome (i.e., seeds not carried on visitor's belongings); however, until now, these links have not been examined. Here, we investigated the links among a visitor's knowledge about biological invasion, awareness of biological invasion, behavior to prevent introduction (cleaning footwear), and being a seed carrier to identify a potential bottleneck between visitor knowledge and ecological outcome. In order to achieve this, we conducted a questionnaire survey and soil sampling from the footwear of visitors to an alpine national park. Soil samples (n = 344) were subjected to a germination experiment, and the number of emerged seedlings was recorded for each sample. We observed seedlings emerging from 27 soil samples (7.8 % of visitors; 44 seedlings in total), comprising non-native species. The degree of a visitor's knowledge about biological invasion increased with the increase in the degree of awareness. However, the high degree of awareness was not linked with the actual behavior of cleaning their footwear before the visit, although footwear cleaning effectively reduced the number of emerged seedlings. We found the lack of a clear association between awareness and behavior (cleaning the footwear) to be the bottleneck. We also investigated the major sources of knowledge about human-mediated seed introduction from footwear and found that television was the most important information source. The key to effectively preventing negative impacts on ecosystems caused by the introduction of non-native species could be to revise methods for informing the community, which will help overcome the bottleneck between awareness and behavior.

Relationship between executive dysfunction and neuropsychiatric symptoms and impaired instrumental activities of daily living among patients with very mild Alzheimer's disease.

OBJECTIVES: Patients with Alzheimer's disease (AD) experience a gradual loss in their ability to perform instrumental activities of daily living (IADLs) from the early stage. A better understanding of the possible factors associated with IADL decline is important for the development of effective rehabilitation and support programs for patients with AD. Thus, we examined the relationships between comprehensive cognitive functions and neuropsychiatric symptoms and IADLs in patients with very mild AD. METHODS: In total, 230 outpatients with probable AD were recruited from the Memory Clinic at Kumamoto University Hospital between May 2007 and October 2016. All patients scored ≥21 points on the Mini-Mental State Examination at the first assessment. Relationships between the subdomains of the Lawton IADL scale and neuropsychological/neuropsychiatric tests were examined by multiple regression analysis. All analyses were performed separately in men and women. RESULTS: In female patients, scores on the Frontal Assessment Battery were significantly associated with telephone use ability, shopping, and ability to handle finances. Apathy scores in the Neuropsychiatric Inventory (NPI) were associated with telephone use ability, housekeeping, responsibility for own medications, and ability to handle finances. NPI agitation scores were associated with food preparation and housekeeping. Geriatric Depression Scale scores were associated with telephone use ability and ability to handle finances. In male patients, only NPI apathy scores were associated with telephone use ability. CONCLUSIONS: These results suggest the importance of properly assessing executive function, depression, and apathy at interventions for impaired IADLs among female patients with very mild AD.

Patterns of plant diversity loss and species turnover resulting from land abandonment and intensification in semi-natural grasslands.

Land-use changes cause biodiversity loss in semi-natural ecosystems worldwide. Biotic homogenization has led to biodiversity loss, mainly through declines in species composition turnover. Elucidating patterns of turnover in species composition could enhance our understanding of how anthropogenic activities affect community assembly. Here, we focused on whether the decreasing patterns in plant diversity and turnover of species composition resulting from land-use change vary in two regions. We estimated the species diversity and composition of semi-natural grasslands surrounding paddy fields in satoyama landscapes. We examined the differences in species diversity and composition across three land-use types (abandoned, traditional, and intensified) in two regions (Hyogo and Niigata Prefectures, Japan), which were characterized by different climatic conditions. We then assessed alpha-, beta-, and gamma-diversity to compare the patterns of diversity losses in the two regions as a result of land-use changes. In each region, gamma-diversity was consistently higher in the traditional sites compared to abandoned or intensified sites. The analyses revealed that most of the beta-diversity in traditional sites differed significantly from those of abandoned and intensified sites in both regions. However, the beta-diversity of total and perennial species did not differ between traditional and abandoned sites in the Hyogo region. We noted that the beta-diversity of total and perennial species in intensified sites was much lower than that in the traditional sites of the Niigata region. Overall, the patterns of alpha- and gamma-diversity loss were similar in both study regions. Although the biotic homogenization was caused by intensified land-use in the Niigata region, this hypothesis did not completely explain the loss of biodiversity in the abandoned sites in the Hyogo region. The present study contributes to the growing body of work investigating changes in biodiversity as a result of both biotic homogenization and differentiation in semi-natural ecosystems. Conservationists and policy makers should focus on patterns of species composition responded to land-use changes that continue to increase worldwide.

Why do people with dementia pretend to know the correct answer? A qualitative study on the behaviour of toritsukuroi to keep up appearances.

BACKGROUND: Toritsukuroi is a particular type of behaviour intended to save face or preserve appearances. Clinicians often observe toritsukuroi in people with dementia, but current knowledge about this behaviour is based on clinicians' empirical knowledge rather than on observational studies. This study was designed to clarify which behaviours are related to toritsukuroi based on neuropsychological examinations. METHODS: The subjects were 91 outpatients with dementia. Verbal responses, with the exceptions of 'I don't know' and erroneous answers, were recorded by certificated clinical psychologists and analyzed by qualitative study procedures. A qualitative study was separately conducted by two researchers to identify themes and types of reactions. The themes found through content analysis were organized and labelled by a senior psychiatrist. RESULTS: Among the patients, 41.8% verbally responded in way to 'keep up appearances'. Six distinct thematic categories were identified through conventional content analysis: (i) refuting sudden questions; (ii) disclosing trait; (iii) disclosing experience; (iv) demonstrating slight hesitation; (v) appealing to indifference; and (vi) other. CONCLUSIONS: All the responses that we defined as being toritsukuroi reflect a denial of acquired cognitive impairment. Further study is needed to clarify the association between toritsukuroi and either cognitive function or disease specificity.

Mental health among younger and older caregivers of dementia patients.

AIM: Caregiver burden in dementia is an important issue, but few studies have examined the mental health of younger and older family caregivers by comparing them with age- and gender-matched community residents. We aimed to compare the mental health of dementia caregivers with that of community residents and to clarify factors related to mental health problems in younger and older caregivers. METHODS: We studied 104 dementia caregivers; 46 were younger (<65 years) and 58 were older (≥65 years). A total of 104 community residents who were matched for age and gender were selected. We compared depression (Center for Epidemiologic Studies Depression Scale for younger participants; Geriatric Depression Scale for older participants), health-related quality of life (QOL) short-form health survey (SF-8), sleep problems, and suicidal ideation between the caregivers and community residents by age. Behavioural and psychological symptoms of dementia, activities of daily living (ADL), and instrumental ADL were assessed among patients with dementia using the Neuropsychiatric Inventory, Physical Self-Maintenance Scale, and Lawton Instrumental ADL Scale, respectively. RESULTS: According to SF-8 results, both younger and older caregivers had significantly worse mental QOL than community residents (younger caregivers: 46.3 vs community residents: 49.7, P = 0.017; older caregivers: 48.2 vs community residents: 51.1, P = 0.024) but were not more depressive. Sleep problems were significantly more frequent in younger caregivers (39.1%) than in community residents (17.0%) (P = 0.017). Multiple regression analysis revealed that caregivers' deteriorated mental QOL was associated with patients' behavioural and psychological symptoms of dementia in younger caregivers and with dementia patients' instrumental ADL and female gender in older caregivers. CONCLUSIONS: Dementia caregivers had a lower mental QOL than community residents. To maintain caregivers' mental QOL, it is necessary to provide younger caregivers with skills or professional interventions for dealing with behavioural and psychological symptoms of dementia, and older caregivers must be offered adequate care support.

Cross-cultural study of caregiver burden for Alzheimer's disease in Japan and Taiwan: result from Dementia Research in Kumamoto and Tainan (DeReKaT).

BACKGROUND: Caregiver burden (CB) of Alzheimer's disease (AD) in Taiwan is becoming an urgent social issue as well as that in Japan. The comparison of CB may explain how caregiver feels burden in each country. METHODS: The participants were 343 outpatients with AD and their caregivers of Japan (n = 230) and Taiwan (n = 113). We assessed the CB using the Japanese and Chinese version of Zarit Caregiver Burden Interview (ZBI). The initial analysis was an exploratory factor analysis for each group to confirm the factor structure of ZBI. Then, the multiple-group structural equation modeling (MG-SEM) was used to assess the measurement invariance of ZBI such as configural, metric, and scalar invariances. Lastly, we compared the latent factor means of the ZBI between Japan and Taiwan. RESULTS: In both groups, the confirmatory factor analysis extracted 3 factors which were labeled "Impact on caregiver's life", "Embarrassed/anger", and "Dependency". The MG-SEM indicated an acceptable model fit, and established the partial scalar measurement invariance (comparative fit index (CFI) = 0.901, root mean square error of approximation (RMSEA) = 0.066). When we compared the latent factor means, the score of "Impact on caregiver's life" in Taiwanese caregivers was significantly higher than that in Japanese (p = 0.001). However, "Dependency" in Taiwanese caregivers was lower than that in Japanese (p < 0.001). CONCLUSIONS: Partial measurement invariance allowed comparing the latent factor mean across two countries. The results of comparisons suggested that there may be differences in the way of feeling CB between Japan and Taiwan.

Comparing the driving behaviours of individuals with frontotemporal lobar degeneration and those with Alzheimer's disease.

BACKGROUND: Assessing driving aptitude in dementia patients is critically important for both patient and public safety. However, there have been only a few reports on the driving behaviours and accident risk of patients with dementia, especially frontotemporal lobar degeneration (FTLD). Therefore, we compared the characteristics of driving behaviours in patients with FTLD and those with Alzheimer's disease (AD). METHODS: The subjects were 28 FTLD and 67 AD patients who visited the Department of Psychiatry, Kochi Medical School Hospital. We conducted semi-structured interviews with their families and caregivers about traffic accident history and changes in patient driving behaviours after dementia onset and then compared the findings between the two groups. RESULTS: Overall changes in driving behaviours were reported in 89% (25/28) and 76% (51/67) of the FTLD and AD patients, respectively (P = 0.17). In the FTLD group, difficulty in judging inter-vehicle distances, ignoring road signs and traffic signals, and distraction were reported in 50% (14/28), 61% (17/28), and 50% (14/28) of patients, respectively, and 75% (21/28) patients had caused a traffic accident after dementia onset. The risk of causing an accident was higher in the FTLD group than in the AD group (odds ratio = 10.4, 95% confidence interval = 3.7-29.1). In addition, the mean duration between dementia onset and a traffic accident was 1.35 years in the FTLD group compared with 3.0 years in the AD group (P < 0.01). CONCLUSIONS: Patients with FTLD were more likely to show dangerous driving behaviours than those with AD, and the risk of causing a traffic accident may be higher in patients with FTLD from an early disease stage.

[Discharge Dynamics and Related Factors of Long-stay Patients in Psychiatric Hospitals].

A longstanding challenge in Japan is prolonged psychiatric hospitalization and the associated difficulty of discharge, lost opportunities for patients' social participation, and stagnant reallocation of medical resources. Although the length of stay has been shortened recently on average, its distribution tends to be polarized into high-turnover and long-stay groups. To resolve these problems, we must understand the discharge dynamics of long-stay patients. Three questionnaires were sent to 733 randomly selected psychiatric hospitals (response rate: 24.3%; 178 hospitals, 2,480 patients). One questionnaire was on hospitalized patient numbers for one-year or longer stays as at the end of June 2007, recording each combination of Group (A or B), diagnosis, and hospitalization type. Group A referred to patients continuously hospitalized as at the end of June 2008; Group B referred to those discharged between July 2007 and June 2008. The second questionnaire was on hospital characteristics (founder, bed number, medical function, etc.), and the third questionnaire was on detailed patient characteristics (residential setting post-discharge, etc., for each Group B patient; a maximum of 20 patients per hospital consecutively in order of discharge). Valid data were obtained from 171 hospitals and 2,419 patients, with the latter increasing to 3,543 after weighting. The annual discharge rate (ADR; B/[A+B]) for the entire sample was 16.3%. Regarding the diagnosis, dementia showed the highest ADR (27.8%) and schizophrenia the lowest (13.5%). The ADRs for depression, bipolar disorder, and alcoholism were 23.9, 20.6, and 23.7% respectively. Regarding the hospitalization type, voluntary hospitalization (16.0%) and hospitalization for medical care and protection (16.8%) showed similar ADRs. Regarding the district, ADRs were high in Kinki (19.9%) and Kyushu (18.8%), and low in Kanto (14.1%) and Chugoku/Shikoku (14.2%). Multivariate analyses revealed that discharge within one year was significantly correlated with the diagnosis, district, hospital founder, and presence of psychiatric emergency or acute-phase treatment (acute-phase-type) wards in hospitals, but not with the hospitalization type, presence of psychiatric long-term care wards, or presence of senile dementia wards. The probability of discharge (odds ratio [95% confidence interval]) regarding the diagnosis was higher in dementia (2.47 [2.23-2.74]), alcoholism (2.09 [1.71-2.55]), depression (2.07 [1.65-2.59]), and bipolar disorder (1.70 [1.35-2.16]) than in schizophrenia (reference). Regarding the district, the probability was higher in Kinki (1.32 [1.12-1.54]) and Kyushu (1.27 [1.14-1.42]) than Kanto (reference). The probability was also lower in private hospitals (0.58 [0.51-0.66]) than in public/university hospitals (reference), and higher in hospitals with acute-phase-type wards (1.24 [1.14-1.35]) than in those without them (reference). The most common residential setting post-discharge for the total sample of weighted Group B patients was temporary hospitalization in another department prearranging psychiatric readmission (THAD, 35.8%), followed by death (18.2%), living with families/relatives (LF/R, 11.3%), a residential care facility for the aged (RCF-A, 9.5%), residential care facility for the disabled (RCF-D, 8.6%), hospitalization in another psychiatric hospital (7.4%), living alone (LA, 4.3%), permanent hospitalization in another department (PHAD, 4.3%), and others (0.7%). In dementia, death was common (31.0%) ; LF/R (1.8%) and LA (0.0%) were rare. As the age increased, the proportions of LF/R, LA, RCF-D, RCF-A, PHAD, and death changed; particularly, LA decreased and death increased markedly with age. Additionally, THAD amounted to approximately 40% in every age class of 40 years or older, contrasting with 11.4% in those under 40 years. The study's limitations include a low response rate, the elapsed time after the survey, and lack of attention paid to symptom severity. Nevertheless, it provides valuable insights into long-stay patients, including that discharge is least likely in schizophrenia and most likely via transfer or death for dementia. These results may encourage the efficient promotion of discharge and prevention of prolonged hospitalization according to patients' demographic, clinical, and social conditions.

Association between depression, examination-related stressors, and sense of coherence: the Ronin-Sei study.

AIMS: In the Japanese education system, students who fail university entrance exam often go to special preparatory schools to prepare for the following year's exam. These students are called ronin-sei. The purpose of this study was to clarify: (i) depression and somatic complaints in ronin-sei; and (ii) the association between depression, examination-related stressors, and sense of coherence (SOC). METHODS: A total of 914 ronin-sei from two preparatory schools were asked to answer a self-rating questionnaire. Depression was measured using the Center for Epidemiologic Studies Depression Scale (CES-D) and SOC was measured using the SOC-13 Scale. RESULTS: Overall, 57.9% of subjects were considered to have depression (CES-D ≥ 16) and 19.8% had severe depression (CES-D ≥ 26). Higher CES-D scores were associated with a higher rate of somatic complaints. In hierarchical logistic regression analysis, having no one to talk to about his/her worries and having parents who disagree about the first-choice of university and faculty were independent risk factors for depression and severe depression, respectively, even after controlling for SOC. CONCLUSIONS: Preparatory school students have various somatic complaints, and their depression is in part related to examination-related stressors. To maintain mental health, it is important to enhance SOC, to understand their examination-related stressors and to provide adequate support for these students.

Is sense of coherence helpful in coping with caregiver burden for dementia?

BACKGROUND: Sense of coherence (SOC) is associated with a reduced risk of various health problems and is thought to be a major factor related to the ability to cope with stress. In the present study, we examined the association between caregiver burden and SOC among caregivers to persons with dementia. METHODS: Participants included 274 caregivers or family members of community-dwelling elderly dementia patients. To assess the cognitive function of patients, neuropsychological tests (e.g. Mini-Mental State Examination, Clinical Dementia Rating) were conducted by a clinical psychologist who was well trained in interviewing participants; the tests used a semi-structured interview protocol. Senior neurologists and psychiatrists also independently evaluated the dementia status of patients. To assess the SOC and caregiver burden, a social welfare counsellor asked questions from a 13-item version of the SOC scale and the short, eight-item Japanese version of the Zarit Caregiver Burden Interview (ZBI). RESULTS: Among 78 caregivers of elderly subjects with cognitive impairment due to dementia, the ZBI score was significantly associated with SOC (r = -0.38, P = 0.001). Multiple regression analyses revealed that SOC scores (ß = -0.42, P < 0.001) and Mini-Mental State Examination scores (ß = -0.28, P = 0.009) were significantly associated with ZBI scores (F(2, 76) = 10.51, P < 0.001). SOC was closely associated with personal strain in the ZBI (ß = -0.41, P < 0.001; F(3, 75) = 8.53, P < 0.001). CONCLUSION: Caregivers with a strong SOC may be less prone to experiencing personal strain from their burden. These results suggest that reinforcement of SOC would contribute to reducing the personal strain.

Analysis of Unique Motility of the Unicellular Green Alga Chlamydomonas reinhardtii at Low Temperatures down to -8 °C.

Previous studies of motility at low temperatures in Chlamydomonas reinhardtii have been conducted at temperatures of up to 15 °C. In this study, we report that C. reinhardtii exhibits unique motility at a lower temperature range (-8.7 to 1.7 °C). Cell motility was recorded using four low-cost, easy-to-operate observation systems. Fast Fourier transform (FFT) analysis at room temperature (20-27 °C) showed that the main peak frequency of oscillations ranged from 44 to 61 Hz, which is consistent with the 60 Hz beat frequency of flagella. At lower temperatures, swimming velocity decreased with decreasing temperature. The results of the FFT analysis showed that the major peak shifted to the 5-18 Hz range, suggesting that the flagellar beat frequency was decreasing. The FFT spectra had distinct major peaks in both temperature ranges, indicating that the oscillations were regular. This was not affected by the wavelength of the observation light source (white, red, green or blue LED) or the environmental spatial scale of the cells. In contrast, cells in a highly viscous (3.5 mPa·s) culture at room temperature showed numerous peaks in the 0-200 Hz frequency band, indicating that the oscillations were irregular. These findings contribute to a better understanding of motility under lower-temperature conditions in C. reinhardtii.

Curbing the major and growing threats from invasive alien species is urgent and achievable.

Although invasive alien species have long been recognized as a major threat to nature and people, until now there has been no comprehensive global review of the status, trends, drivers, impacts, management and governance challenges of biological invasions. The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Thematic Assessment Report on Invasive Alien Species and Their Control (hereafter 'IPBES invasive alien species assessment') drew on more than 13,000 scientific publications and reports in 15 languages as well as Indigenous and local knowledge on all taxa, ecosystems and regions across the globe. Therefore, it provides unequivocal evidence of the major and growing threat of invasive alien species alongside ambitious but realistic approaches to manage biological invasions. The extent of the threat and impacts has been recognized by the 143 member states of IPBES who approved the summary for policymakers of this assessment. Here, the authors of the IPBES assessment outline the main findings of the IPBES invasive alien species assessment and highlight the urgency to act now.

The formation of a rolling larval chamber as the unique structural gall of a new species of cynipid gall wasps.

Insect galls, which often have complex external and internal structures, are believed to have adaptive significance for the survival of insects inside galls. A unique internal structure was discovered in the gall of a new cynipid species, Belizinella volutum Ide & Koyama, sp. nov., where the larval chamber could roll freely in the internal air space of the gall. Observations of the live galls using micro-computed tomography (micro-CT) revealed its formation process. The larval chamber becomes isolated from the internal parenchyma soon after the gall reaches the maximum diameter and is able to roll as the internal air space is expanding from the surrounding parenchyma to the outer gall wall. The enemy hypothesis could partly explain the adaptive significance of the unique structure of the gall of B. volutum.

Specific alien plant species predominantly deliver nectar sugar and pollen but are not preferentially visited by wild pollinating insects in suburban riparian ecosystems.

The invasion of alien plants has been rapidly proceeding worldwide due to urbanisation. This might be beneficial to wild pollinating insects, since some alien plant species have large flowers and/or long flowering periods, which can increase nectar sugar and pollen availability. To determine the relative contribution of alien plants to floral resource supply and whether resource-rich alien plants, if any, serve as an important food source of pollinating insects, we performed year-round field observations in suburban riverbanks. We quantified the per-unit-area availability of nectar sugar and pollen delivered by alien and native flowering species and counted wild flower visitors (bees and wasps, hoverflies and butterflies) per plant species. The available nectar sugar and pollen per area were predominantly delivered by a few specific alien species, and the relative contribution of other species to floral resource provision was low throughout the period that wild flower visitors were observed. Nonetheless, the resource-rich alien plants were not visited by as many insects as expected based on their contribution to resource provision. Rather, on a yearly basis, these plants received equal or even fewer visits than other flowering species, including resource-poor natives. We show that despite their great contribution to the gross floral resource supply, resource-rich alien plants do not serve as a principal food source for wild pollinating insects, and other plants, especially natives, are still needed to satisfy insect demand. For the conservation of pollinating insects in suburban ecosystems, maintaining floral resource diversity would be more beneficial than having an increase in gross floral resources by allowing the dominance of specific alien plants.