Dietary resistant starch enhances immune health of the kidney in diabetes via promoting microbially-derived metabolites and dampening neutrophil recruitment.

BACKGROUND: Dietary-resistant starch is emerging as a potential therapeutic tool to limit the negative effects of diabetes on the kidneys. However, its metabolic and immunomodulatory effects have not yet been fully elucidated. METHODS: Six-week-old db/db mice were fed a diet containing 12.5% resistant starch or a control diet matched for equivalent regular starch for 10 weeks. db/m mice receiving the control diet were utilised as non-diabetic controls. Freshly collected kidneys were digested for flow cytometry analysis of immune cell populations. Kidney injury was determined by measuring albuminuria, histology, and immunohistochemistry. Portal vein plasma was collected for targeted analysis of microbially-derived metabolites. Intestinal histology and tight junction protein expression were assessed. RESULTS: Resistant starch limited the development of albuminuria in db/db mice. Diabetic db/db mice displayed a decline in portal vein plasma levels of acetate, propionate, and butyrate, which was increased with resistant starch supplementation. Diabetic db/db mice receiving resistant starch had a microbially-derived metabolite profile similar to that of non-diabetic db/m mice. The intestinal permeability markers lipopolysaccharide and lipopolysaccharide binding protein were increased in db/db mice consuming the control diet, which was not seen in db/db mice receiving resistant starch supplementation. Diabetes was associated with an increase in the kidney neutrophil population, neutrophil activation, number of C5aR1+ neutrophils, and urinary complement C5a excretion, all of which were reduced with resistant starch. These pro-inflammatory changes appear independent of fibrotic changes in the kidney. CONCLUSIONS: Resistant starch supplementation in diabetes promotes beneficial circulating microbially-derived metabolites and improves intestinal permeability, accompanied by a modulation in the inflammatory profile of the kidney including neutrophil infiltration, complement activation, and albuminuria. These findings indicate that resistant starch can regulate immune and inflammatory responses in the kidney and support the therapeutic potential of resistant starch supplementation in diabetes on kidney health.

Prevalence of Renal Neoplasia in Autosomal Dominant Polycystic Kidney Disease: Systematic Review and Meta-Analysis.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a common inherited condition; however, its relationship with renal cell carcinoma (RCC) remains unclear. This paper aims to establish the prevalence of RCC and its subtypes amongst ADPKD patients. METHODS: A database search was conducted to retrieve studies reporting RCC occurrence within ADPKD patients until July 2023. Key outcomes included number and subtype of RCC cases, and number of RCCs presenting incidentally. A random-effects meta-analysis was performed. RESULTS: Our search yielded 569 articles, 16 met the inclusion criteria. Nephrectomy specimens from 1,147 ADPKD patients were identified. Of studies reporting per-kidney results (n = 13), 73 RCCs were detected amongst 1,493 kidneys, equating to a per-kidney prevalence of 4.3% (95% CI, 3.1-5.7, I2 = 15.7%). 75 ADPKD patients were found to have RCC (75/1,147), resulting in a per-person prevalence of 5.7% (95% CI, 3.7-7.9, I2 = 40.3%) (n = 16). As 7 patients had bilateral disease, 82 RCCs were detected in total. Of these, 39 were clear cell RCC, 35 were papillary and 8 were other. As such, papillary RCCs made up 41.1% (95% CI, 25.9-56.9, I2 = 18.1%) of detected cancers. The majority of RCCs were detected incidentally (72.5% [95% CI, 43.7-95.1, I2 = 66.9%]). CONCLUSION: ADPKD appears to be associated with the papillary RCC subtype. The clinical implications of these findings are unclear, however, may become apparent as outcomes and life expectancy amongst APDKD patients improve.

Resistant Starch as a Dietary Intervention to Limit the Progression of Diabetic Kidney Disease.

Diabetes is the leading cause of kidney disease, and as the number of individuals with diabetes increases there is a concomitant increase in the prevalence of diabetic kidney disease (DKD). Diabetes contributes to the development of DKD through a number of pathways, including inflammation, oxidative stress, and the gut-kidney axis, which may be amenable to dietary therapy. Resistant starch (RS) is a dietary fibre that alters the gut microbial consortium, leading to an increase in the microbial production of short chain fatty acids. Evidence from animal and human studies indicate that short chain fatty acids are able to attenuate inflammatory and oxidative stress pathways, which may mitigate the progression of DKD. In this review, we evaluate and summarise the evidence from both preclinical models of DKD and clinical trials that have utilised RS as a dietary therapy to limit the progression of DKD.

The relative influence of cross-seasonal and local weather effects on the breeding success of a migratory songbird.

In seasonal environments, fluctuating early-season weather conditions and short breeding windows limit reproductive opportunities such that breeding earlier or later than the optimum may be particularly costly. Given the risk of early-season energy limitations, time- and energy-based carry-over effects stemming from environmental conditions across the annual cycle may have pronounced consequences for breeding phenology and fitness. Generally, when and where environmental conditions are most influential are poorly understood, limiting our ability to predict the future of climate-sensitive populations. For an alpine-breeding, migratory population of horned lark Eremophila alpestris in northern British Columbia, Canada (54.8°N), we assessed how weather conditions across the annual cycle influenced clutch initiation date and offspring development. We also addressed how cross-seasonal effects on breeding parameters combine to influence reproductive fitness. With 12 years of breeding data and 3 years of migration data, we used a sliding window approach to identify points during the annual cycle when weather events most influenced breeding phenology and offspring development. Consequences for breeding success were assessed using nest survival simulations. Average clutch initiation date varied up to 11 days among years but did not advance from 2003 to 2019. Warmer temperatures at stopover and breeding sites advanced clutch initiation, but winter conditions had no effect. Sub-zero stopover temperatures carried over to prolong offspring development independent of clutch initiation date, potentially indicating energy-based carry-over effects acting on parental investment. Nest survival decreased with both later clutch initiation and prolonged offspring development such that females nesting earlier and fledging offspring at a younger age were up to 45% more likely to reproduce successfully. We demonstrate that stronger carry-over effects originated from environmental conditions closer to the breeding site in time and space, as well as the potential for energy-based mechanisms to link pre-breeding conditions to reproductive fitness. We also highlight the importance of extended stopovers for songbirds breeding in seasonal environments, particularly given that climatic conditions are becoming increasingly decoupled across stages of the annual cycle. Understanding the cross-seasonal mechanisms shaping breeding decisions in stochastic environments allows for more accurate predictions of population-level responses to climate change.

Les variations saisonnières de l'environnement, notamment due aux conditions climatiques changeantes en début de saison ainsi que la réduction de la période propice à l'accouplement contraint fortement les possibilités de reproduction. Dans ces conditions, s'accoupler avant ou après le moment optimal peut s'avérer particulièrement coûteux. Les effets de report (temporels et énergétiques) causés par ces variations environnementales peuvent avoir des conséquences notables sur la phénologie de la reproduction, et ultimement sur la valeur sélective des individus. Où et quand les effets des conditions environnementales sont le plus critiques reste encore méconnu, limitant notre capacité à prédire le futur des populations sensibles aux variations climatiques. Ici, nous avons évalué comment des conditions climatiques au cours de l'année influencent la date de ponte et le développement des oisillons dans une population migratrice d'Alouette hausse-col Eremophila alpestris se reproduisant en milieux alpin. Nous tirons profit de données issues de 12 ans de suivit de la reproduction et de 3 ans de suivit migratoire, et utilisons une approche dite de 'sliding window' pour identifier les moments du cycle annuel pour lequel le climat a eu le plus d'influence sur la phénologie de la reproduction et le développement des oisillons. La date moyenne de ponte s'avère variable d'une année à l'autre (certaine différence allant jusqu'à 11 jours), mais ne se décale pas sur la période de 2003 à 2019. Nos résultats montrent que des conditions climatiques plus chaudes lors des haltes migratoires ainsi que sur les sites de reproductions rendent la date de ponte plus précoces. Des températures négatives lors des haltes migratoires aussi ont pour conséquences un temps de développement des oisillons plus long, et ceci indépendamment de la date de ponte. Cela suggère des effets de report, notamment énergétique, affectant l'investissement des parents. Nos résultats montrent que la survie au nid diminue lorsque la date de ponte est plus tardive ou que le temps de développement des oisillons est rallongé. De cette manière, les femelles commençants la nidification plus tôt et pour qui les oisillons quittent le nid plus tôt ont 45% plus de chance de se reproduire avec succès. Nous démontrons que des conditions environnementales proche du site de reproduction (que ce soit dans le temps ou dans l'espace) cause un fort effet de report, et suggérons un possible mécanisme reliant les conditions climatiques pré-reproductives au succès reproducteur. De plus, nous mettons en lumière l'importance des haltes migratoires prolongées pour la reproduction des passereaux en environnement saisonnier, particulièrement du fait que les conditions climatiques sont de plus en plus découplées au cours des les étapes du cycle annuel. Une meilleure compréhension des mécanismes inter-saisonniers influençant les décisions de reproduction en environnement stochastique permettrait de mieux prédire les réponses des populations aux changements climatiques.

Caring for a Relative With Dementia in Long-Term Care During COVID-19.

OBJECTIVES: The COVID-19 pandemic created unique stressors for caregivers of persons with dementia living in long-term care (LTC) facilities. The purpose of this qualitative study was to identify the challenges associated with caring for a relative with dementia in LTC during the pandemic, as well as resources, strategies, and practices caregivers found helpful in coping with COVID-19. DESIGN: This study was conducted within the context of an ongoing randomized controlled trial of a psychosocial intervention to support caregivers. Open-ended survey responses (n = 125) and semistructured interviews with a subset of the sample (n = 20) collected between June 2020 and June 2021 explored caregivers' experiences during COVID-19. SETTING AND PARTICIPANTS: Participants included 125 family caregivers of persons with dementia living in residential LTC. METHODS: Thematic analysis was used to identify themes capturing caregivers' experiences. RESULTS: In addition to concerns about COVID-19 infection, participants reported key challenges such as the difficulty of maintaining contact with relatives because of visiting restrictions, lack of information about relatives' health and well-being, worries about overburdened LTC staff, impossibility of returning relatives home from the LTC facility, and fears about relatives dying alone. Participants also identified resources, strategies, and practices that they perceived as helpful, including effective infection prevention within the LTC facility, good communication with LTC staff, and creative strategies for connecting with their relatives. CONCLUSIONS AND IMPLICATIONS: This qualitative analysis informs recommendations for practice within LTC facilities, as well as supports that may help caregivers manage stressful situations in the context of COVID-19. Vaccination and testing protocols should be implemented to maximize family caregivers' opportunities for in-person contact with relatives in LTC, as alternative visiting modalities were often unsatisfactory or unfeasible. Informing caregivers regularly about individual residents' needs and status is crucial. Supports for bereaved caregivers should address complicated grief and feelings of loss.

Sex differences in long-term behavioral alterations, especially anxiety, following prenatal fluoxetine exposure in C57BL/6 mice.

Evidence demonstrates that psychiatric disorders during pregnancy are detrimental to the offspring. Many disorders are treated with SSRIs and increasing numbers of pregnant women now receive these drugs during gestation. The long-term neurobehavioral consequences of prenatal SSRI exposure require further evaluation. This study examined the effects of prenatal fluoxetine exposure in mice in an extensive battery of behaviors related to neurodevelopment, mood, social, and repetitive behaviors. C57BL/6J dams were administered fluoxetine at a low (0.6 mg/kg/day) or high (6 mg/kg/day) dose or saline from embryonic days 8 to 18. Juvenile mice were tested for changes in ultrasonic vocalizations and neuromotor development. In adulthood, offspring were tested for changes in behaviors related to anxiety, depression, social, and repetitive behaviors. Prenatal exposure to fluoxetine impaired surface righting reflex at P5, and sex-dependently reduced the frequency of ultrasonic vocalizations in juvenile males but not females. In adulthood, both males and females prenatally exposed to high, but not low, doses of fluoxetine exhibited an increase in repetitive behaviors in the marble burying task and a decrease in sucrose preference. Males, but not females, exposed to fluoxetine exhibited increased anxiety-related behaviors in the elevated plus maze. Prenatal fluoxetine exposure did not affect other adult behaviors including social preference, self-grooming, passive avoidance and open field activity. These findings suggest males are more sensitive than females to disruptions in serotonin balance during prenatal development and highlight the need for additional systematic and mechanistic studies to evaluate the impact of fluoxetine exposure during other periods of gestation.

Combining point counts and autonomous recording units improves avian survey efficacy across elevational gradients on two continents.

Accurate biodiversity and population monitoring is a requirement for effective conservation decision making. Survey method bias is therefore a concern, particularly when research programs face logistical and cost limitations.We employed point counts (PCs) and autonomous recording units (ARUs) to survey avian biodiversity within comparable, high elevation, temperate mountain habitats at opposite ends of the Americas: nine mountains in British Columbia (BC), Canada, and 10 in southern Chile. We compared detected species richness against multiyear species inventories and examined method-specific detection probability by family. By incorporating time costs, we assessed the performance and efficiency of single versus combined methods.Species accumulation curves indicate ARUs can capture ~93% of species present in BC but only ~58% in Chile, despite Chilean mountain communities being less diverse. The avian community, rather than landscape composition, appears to drive this dramatic difference. Chilean communities contain less-vocal species, which ARUs missed. Further, 6/13 families in BC were better detected by ARUs, while 11/11 families in Chile were better detected by PCs. Where survey conditions differentially impacted method performance, PCs mostly varied over the morning and with canopy cover in BC, while ARUs mostly varied seasonally in Chile. Within a single year of monitoring, neither method alone was predicted to capture the full avian community, with the exception of ARUs in the alpine and subalpine of BC. PCs contributed little to detected diversity in BC, but including this method resulted in negligible increases in total time costs. Combining PCs with ARUs in Chile significantly increased species detections, again, for little cost.Combined methods were among the most efficient and accurate approaches to capturing diversity. We recommend conducting point counts, while ARUs are being deployed and retrieved in order to capture additional diversity with minimal additional effort and to flag methodological biases using a comparative framework.

Vagus Nerve Stimulation Reduces Indomethacin-Induced Small Bowel Inflammation.

Crohn's disease is a chronic, idiopathic condition characterized by intestinal inflammation and debilitating gastrointestinal symptomatology. Previous studies of inflammatory bowel disease (IBD), primarily in colitis, have shown reduced inflammation after electrical or pharmacological activation of the vagus nerve, but the scope and kinetics of this effect are incompletely understood. To investigate this, we studied the effect of electrical vagus nerve stimulation (VNS) in a rat model of indomethacin-induced small intestinal inflammation. 1 min of VNS significantly reduced small bowel total inflammatory lesion area [(mean ± SEM) sham: 124 ± 14 mm2, VNS: 62 ± 14 mm2, p = 0.002], intestinal peroxidation and chlorination rates, and intestinal and systemic pro-inflammatory cytokine levels as compared with sham-treated animals after 24 h following indomethacin administration. It was not known whether this observed reduction of inflammation after VNS in intestinal inflammation was mediated by direct innervation of the gut or if the signals are relayed through the spleen. To investigate this, we studied the VNS effect on the small bowel lesions of splenectomized rats and splenic nerve stimulation (SNS) in intact rats. We observed that VNS reduced small bowel inflammation also in splenectomized rats but SNS alone failed to significantly reduce small bowel lesion area. Interestingly, VNS significantly reduced small bowel lesion area for 48 h when indomethacin administration was delayed. Thus, 1 min of electrical activation of the vagus nerve reduced indomethacin-induced intestinal lesion area by a spleen-independent mechanism. The surprisingly long-lasting and spleen-independent effect of VNS on the intestinal response to indomethacin challenge has important implications on our understanding of neural control of intestinal inflammation and its potential translation to improved therapies for IBD.

STRENGTH AND FATIGUE MEASUREMENTS OF THE HIP FLEXOR AND HIP EXTENSOR MUSCLES: TEST-RETEST RELIABILITY AND LIMB DOMINANCE EFFECT.

BACKGROUND: Standardized testing of hip muscle strength and fatigue in the sagittal plane is important for assessing, treating and preventing a number of trunk and lower extremity pathologies. Furthermore, individuals displaying asymmetries of muscle strength between limbs are more likely to sustain an injury. PURPOSE: To evaluate the test-retest reliability of isometric strength and isokinetic fatigue measurements of the hip flexor and hip extensor muscles, and to examine whether there is a significant limb dominance effect on strength, fatigue and flexor-extensor ratios. STUDY DESIGN: Cross-sectional study. METHODS: To evaluate reliability, 30 healthy individuals (33.2 + /- 13.1 years) were included. On a separate occasion, 24 healthy individuals (29.0 + /- 10.3 years) participated to assess between-limb differences. Reliability was established using intraclass correlation coefficients (ICCs), standard error of measurements (SEM) and minimal detectable change (MDC). Isometric strength (best peak torque of three maximal contractions; Nm/kg), isokinetic fatigue (total work of 20 consecutive maximal concentric flexor-extensor contractions at 120 °/s; Joule/kg), and flexor-extensor ratios, were recorded using a Biodex dynamometer. RESULTS: Reliability was good-to-excellent (ICCs>0.83) and measurement errors were acceptable (SEM<13.6% and MDC%<37.8%). No significant between-limb differences in strength, fatigue and flexor-extensor ratios were detected. CONCLUSIONS: Isometric strength and isokinetic fatigue of the hip flexor and hip extensor muscles can be reliably assessed in healthy individuals using the Biodex dynamometer. Limb dominance did not significantly affect strength, fatigue or flexor-extensor ratios. LEVEL OF EVIDENCE: 2b.

Adenylyl Cyclase 6 Mediates Inhibition of TNF in the Inflammatory Reflex.

Macrophage cytokine production is regulated by neural signals, for example in the inflammatory reflex. Signals in the vagus and splenic nerves are relayed by choline acetyltransferase+ T cells that release acetylcholine, the cognate ligand for alpha7 nicotinic acetylcholine subunit-containing receptors (α7nAChR), and suppress TNF release in macrophages. Here, we observed that electrical vagus nerve stimulation with a duration of 0.1-60 s significantly reduced systemic TNF release in experimental endotoxemia. This suppression of TNF was sustained for more than 24 h, but abolished in mice deficient in the α7nAChR subunit. Exposure of primary human macrophages and murine RAW 264.7 macrophage-like cells to selective ligands for α7nAChR for 1 h in vitro attenuated TNF production for up to 24 h in response to endotoxin. Pharmacological inhibition of adenylyl cyclase (AC) and knockdown of adenylyl cyclase 6 (AC6) or c-FOS abolished cholinergic suppression of endotoxin-induced TNF release. These findings indicate that action potentials in the inflammatory reflex trigger a change in macrophage behavior that requires AC and phosphorylation of the cAMP response element binding protein (CREB). These observations further our mechanistic understanding of neural regulation of inflammation and may have implications for development of bioelectronic medicine treatment of inflammatory diseases.

Local temperatures predict breeding phenology but do not result in breeding synchrony among a community of resident cavity-nesting birds.

Weather and ecological factors are known to influence breeding phenology and thus individual fitness. We predicted concordance between weather conditions and annual variation in phenology within a community of eight resident, cavity-nesting bird species over a 17-year period. We show that, although clutch initiation dates for six of our eight species are correlated with local daily maximum temperatures, this common driver does not produce a high degree of breeding synchrony due to species-specific responses to conditions during different periods of the preceding winter or spring. These "critical temperature periods" were positively associated with average lay date for each species, although the interval between critical periods and clutch initiation varied from 4-78 days. The ecological factors we examined (cavity availability and a food pulse) had an additional influence on timing in only one of our eight focal species. Our results have strong implications for understanding heterogeneous wildlife responses to climate change: divergent responses would be expected within communities where species respond to local conditions within different temporal windows, due to differing warming trends between winter and spring. Our system therefore indicates that climate change could alter relative breeding phenology among sympatric species in temperate ecosystems.

Wind conditions on migration influence the annual survival of a neotropical migrant, the western yellow-breasted chat (Icteria virens auricollis).

BACKGROUND: Long-distance migratory birds in North America have undergone precipitous declines over the past half-century. Although the trend is clear, for many migrating species underpinning the exact causes poses a challenge to conservation due to the numerous stressors that they encounter. Climate conditions during all phases of their annual cycle can have important consequences for their survival. Here, using 15 years of capture-recapture dataset, we determined the effects of various climate factors during the breeding, wintering, and migrating stages on the annual survival of a western yellow-breasted chat (Icteria virens auricollis) population breeding in southwestern Canada. RESULTS: El Niño effects over the entire annual cycle had little influence on the annual apparent survival of yellow-breasted chats. However, we found evidence that wind conditions during migration, specifically average westerly wind speed or the frequency of storm events, had significant adverse effects on adult annual apparent survival. In comparison, precipitation levels on wintering ground had little to no influence on adult annual apparent survival, whereas growing degree days on the breeding ground had moderate but positive effects. CONCLUSIONS: In the face of climate change and its predicted impacts on climate processes, understanding the influence of weather conditions on the survival of migrating birds can allow appropriate conservation strategies to be adopted for chats and other declining neotropical migrants.

Test-Retest Reliability of Isokinetic Knee Strength Measurements in Children Aged 8 to 10 Years.

BACKGROUND: Isokinetic dynamometry is a useful tool to objectively assess muscle strength of children and adults in athletic and rehabilitative settings. This study examined test-retest reliability of isokinetic knee strength measurements in children aged 8 to 10 years and defined limits for the minimum difference (MD) in strength that indicates a clinically important change. HYPOTHESIS: Isokinetic knee strength measurements (using the Biodex System 4) in children will provide reliable results. STUDY DESIGN: Descriptive laboratory study. METHODS: In 22 healthy children, 5 maximal concentric (CON) knee extensor (KE) and knee flexor (KF) contractions at 2 angular velocities (60 deg/s and 180 deg/s) and 5 maximal eccentric (ECC) KE/KF contractions at 60 deg/s were assessed 7 days apart. The intraclass correlation coefficient (ICC2.1) was used to examine relative reliability, and the MD was calculated on the basis of standard error of measurement. RESULTS: ICCs for CON KE/KF peak torque measurements were fair to excellent (range, 0.49-0.81). The MD% values for CON KE and KF ranged from 31% to 37% at 60 deg/s and from 34% to 39% at 180 deg/s. ICCs in the ECC mode were good (range, 0.60-0.70), but associated MD% values were high (>50%). There was no systematic error for CON KE/KF and ECC KE strength measurements at 60 deg/s, but systematic error was found for all other measurements. CONCLUSION: The dynamometer provides a reliable analysis of isokinetic CON knee strength measurements at 60 deg/s in children aged 8 to 10 years. Measurements at 180 deg/s and in the ECC mode were not reliable, indicating a need for more familiarization prior to testing. CLINICAL RELEVANCE: The MD values may help clinicians to determine whether a change in knee strength is due to error or intervention.

Individual quality explains association between plumage colouration, arrival dates and mate acquisition in yellow warblers (Setophaga petechia).

BACKGROUND: In many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. We then evaluated whether winter habitat use (inferred using δ13C and δ15N signatures of winter grown greater-coverts) influenced alternate plumage colouration, after controlling for individual quality using basic plumage colouration. Finally, we investigated whether basic and alternate plumage colouration influenced arrival dates, mate acquisition, breeding phenology and reproductive success of yellow warblers breeding in southern (Revelstoke, B.C.) and arctic (Inuvik, N.W.T.) Canada. RESULTS: The colour (chroma and hue) of tail feathers, grown on the breeding grounds, was not related to subsequent winter habitat use. Greater covert and tail feather colour (chroma and hue) were correlated, suggesting genetics and/or individual quality played a role in pigment deposition. After controlling for individual difference in tail colour, δ13C values did not explain any variation in greater covert colour, but birds with high δ15N signatures had greater coverts with higher chroma. Male arrival dates varied with tail chroma in Revelstoke and tail hue in Inuvik. Males that arrived early paired with older and/or more colourful mates that initiated clutches earlier, and at one site (Revelstoke) were more likely to fledge young. In addition, in Revelstoke (but not Inuvik) males with high tail hue also acquired more colourful mates. In contrast, after controlling for individual differences in tail colour, greater covert colour did not affect male arrival date, the quality of the mate obtained or reproductive success in either population. CONCLUSIONS: Our results suggest that plumage colour effects on breeding phenology and mate acquisition result from differences in the intrinsic quality of individuals rather than a carry-over effect of winter habitat use.

Wind speed during migration influences the survival, timing of breeding, and productivity of a neotropical migrant, Setophaga petechia.

Over the course of the annual cycle, migratory bird populations can be impacted by environmental conditions in regions separated by thousands of kilometers. We examine how climatic conditions during discrete periods of the annual cycle influence the demography of a nearctic-neotropical migrant population of yellow warblers (Setophaga petechia), that breed in western Canada and overwinter in Mexico. We demonstrate that wind conditions during spring migration are the best predictor of apparent annual adult survival, male arrival date, female clutch initiation date and, via these timing effects, annual productivity. We find little evidence that conditions during the wintering period influence breeding phenology and apparent annual survival. Our study emphasizes the importance of climatic conditions experienced by migrants during the migratory period and indicates that geography may play a role in which period most strongly impacts migrant populations.

Assessment of fall-related self-efficacy and activity avoidance in people with Parkinson's disease.

BACKGROUND: Fear of falling (FOF) is common in Parkinson's disease (PD), and it is considered a vital aspect of comprehensive balance assessment in PD. FOF can be conceptualized differently. The Falls-Efficacy Scale (FES) assesses fall-related self-efficacy, whereas the Survey of Activities and Fear of Falling in the Elderly (SAFFE) assesses activity avoidance due to the risk of falling. This study aimed at investigating the validity and reliability of FES and SAFFE in people with PD. METHODS: Seventy-nine people with PD (mean age; 64 years, SD 7.2) completed the Swedish version of FES(S), SAFFE and the physical functioning (PF) scale of the 36-Item Short-Form Health Survey (SF-36). FES(S) and SAFFE were administered twice, with an 8.8 (SD 2.3) days interval. Assumptions for summing item scores into total scores were examined and score reliability (Cronbach's alpha and test-retest reliability) were calculated. Construct validity was assessed by examining the pattern of Spearman correlations (rs) between the FES(S)/SAFFE and other variables, and by examining differences in FES(S)/SAFFE scores between fallers and non-fallers, genders, and between those reporting FOF and unsteadiness while turning. RESULTS: For both scales, item mean scores (and standard deviations) were roughly similar and corrected item-total correlations exceeded 0.4. Reliabilities were ≥ 0.87. FES(S)-scores correlated strongest (rs, -0.74, p < 0.001) with SAFFE-scores, whereas SAFFE-scores correlated strongest with PF-scores (rs, -0.76, p < 0.001). Both scales correlated weakest with age (rs ≤ 0.08). Experiencing falls, unsteadiness while turning, and FOF was associated with lower fall-related self-efficacy and higher activity avoidance. CONCLUSIONS: This study provides initial support for the score reliability and validity of the FES(S) and SAFFE in people with PD.