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Introduction: Seasonality in depressive and bipolar disorders, are recognized in the ICD-10/11 and DSM-5 diagnostic systems. The existence of a seasonal pattern of hospital diagnosis of major depression, bipolar disorder and prescription of antidepressant medications has not been evaluated in the Danish population. Methods: We retrieved date and year for all first-time hospital contacts with depression or bipolar disorder between 1999 and 2019, registered in the Danish National Patient Registry. Depression was defined using the ICD-10 F32-F33 codes, and for bipolar disorder the F30 or F31 codes. Date and year of all first-time purchases of antidepressant medications with ATC codes (N06A) between 1999 and 2021 were retrieved from the Danish National Prescription Registry, containing information on all prescribed drugs dispensed at pharmacies since 1995. Data on sunlight hours from 2012 to 2021 were retrieved from the Danish Metrological Institute. Results: Incidences of hospital diagnoses as well as purchases of medication varied with month and season. The monthly variations were larger for antidepressant medication and smallest for bipolar disorder. The multiple linear regression analysis showed that number of first-time diagnoses of depression or bipolar disorder did not correlate with season. For antidepressant medication the number of first-time prescriptions was significantly lower in summer compared to the winter season. Conclusion: This study found a seasonal variation of first-time prescriptions of antidepressant medication. We did not find a seasonal variation in first-time hospital diagnoses. Further research looking into depression severity, polarity of bipolar illness episodes, lag-time for sunlight exposure, and specific parts of the yearly photoperiods should be conducted.

BACKGROUND: Diesel exhaust (DE) exposures pose concerns for serious health effects, including asthma and lung cancer, in California communities burdened by multiple stressors. OBJECTIVE: To evaluate DE exposures in disproportionately impacted communities using biomonitoring and compare results for adults and children within and between families. METHODS: We recruited 40 families in the San Francisco East Bay area. Two metabolites of 1-nitropyrene (1-NP), a marker for DE exposures, were measured in urine samples from parent-child pairs. For 25 families, we collected single-day spot urine samples during two sampling rounds separated by an average of four months. For the 15 other families, we collected daily spot urine samples over four consecutive days during the two sampling rounds. We also measured 1-NP in household dust and indoor air. Associations between urinary metabolite levels and participant demographics, season, and 1-NP levels in dust and air were evaluated. RESULTS: At least one 1-NP metabolite was present in 96.6% of the urine samples. Detection frequencies for 1-NP in dust and indoor air were 97% and 74%, respectively. Results from random effect models indicated that levels of the 1-NP metabolite 6-hydroxy-1-nitropyrene (6-OHNP) were significantly higher in parents compared with their children (p-value = 0.005). Urinary 1-NP metabolite levels were generally higher during the fall and winter months. Within-subject variability was higher than between-subject variability (~60% of total variance versus ~40%, respectively), indicating high short-term temporal variability. IMPACT: Biomonitoring, coupled with air monitoring, improves understanding of hyperlocal air pollution impacts. Results from these studies will inform the design of effective exposure mitigation strategies in disproportionately affected communities.

Influenza viruses continually evolve new antigenic variants, through mutations in epitopes of their major surface proteins, hemagglutinin (HA) and neuraminidase (NA). Antigenic drift potentiates the reinfection of previously infected individuals, but the contribution of this process to variability in annual epidemics is not well understood. Here, we link influenza A(H3N2) virus evolution to regional epidemic dynamics in the United States during 1997-2019. We integrate phenotypic measures of HA antigenic drift and sequence-based measures of HA and NA fitness to infer antigenic and genetic distances between viruses circulating in successive seasons. We estimate the magnitude, severity, timing, transmission rate, age-specific patterns, and subtype dominance of each regional outbreak and find that genetic distance based on broad sets of epitope sites is the strongest evolutionary predictor of A(H3N2) virus epidemiology. Increased HA and NA epitope distance between seasons correlates with larger, more intense epidemics, higher transmission, greater A(H3N2) subtype dominance, and a greater proportion of cases in adults relative to children, consistent with increased population susceptibility. Based on random forest models, A(H1N1) incidence impacts A(H3N2) epidemics to a greater extent than viral evolution, suggesting that subtype interference is a major driver of influenza A virus infection ynamics, presumably via heterosubtypic cross-immunity.

Disentangling the effects of cyclical variability in environmental forcing and long-term climate change on natural communities is a major challenge for ecologists, managers, and policy makers across ecosystems. Here we examined whether the vertical distribution of rocky intertidal taxa has shifted with sea-level variability occurring at multiple temporal scales and/or long-term anthropogenic sea-level rise (SLR). Because of the distinct zonation characteristic of intertidal communities, any shift in tidal dynamics or average sea level is expected to have large impacts on community structure and function. We found that across the Northeast Pacific Coast (NPC), sea level exhibits cyclical seasonal variability, tidal amplitude exhibits ecologically significant variability coherent with the 18.6-year periodicity of lunar declination, and long-term sea-level rise is occurring. Intertidal taxa largely do not exhibit significant vertical distribution shifts coherent with short-term (monthly to annual) sea-level variability but do exhibit taxa-specific vertical distribution shifts coherent with cyclical changes in lunar declination and long-term SLR at decadal timescales. Finally, our results show that responses to cyclical celestial mechanics and SLR vary among taxa, primarily according to their vertical distribution. Long-term SLR is occurring on ecologically relevant scales, but the confounding effects of cyclical celestial mechanics make interpreting shifts in zonation or community structure challenging. Such cyclical dynamics alternatingly amplify and dampen long-term SLR impacts and may modify the impacts of other global change related stressors, such as extreme heat waves and swell events, on intertidal organisms living at the edge of their physiological tolerances. As a result, intertidal communities will likely experience cyclical periods of environmental stress and concomitant nonlinear shifts in structure and function as long-term climate change continues. Our re

Syfte: Att skapa en holistisk och differentierad bild av hur företag kan hantera och anpassa sig till föränderliga marknadsförhållanden och därigenom nyansera forskningsfältet och erbjuda nya insikter som kan gynna både forskning och praktiken inom området. Forskningsfrågor: (1) Hur arbetar fallföretaget Hestra Gloves med de säsongsbaserade utmaningarna inom textilindustrin med fokus på lagerhantering och prognostisering? (2) Hur påverkar det faktumet att vara ett familjeägt företag Hestra Gloves i sitt arbete med resursallokering, med fokus på lager? Metod: Studien utgår från en kvalitativ forskningsansats där det empiriska materialet har insamlats genom fyra noggrant valda intervjuer från fallföretaget. Teori: Består av begreppsförklaring och tidigare forskning som berör nyckelorden. Vidare presenteras även kvantitativa och kvalitativa metoder för prognostiseringsarbete. Slutsats: Fallföretaget hanterar efterfrågeförändringar genom en kombination av kvantitativa och kvalitativa prognosmetoder. Trots risken med hög kapitalbindning väljer företaget att hålla stora lager för att säkerställa leverans vid hög efterfrågan, en strategi möjliggjord av dess familjeägda struktur och stora eget kapital., Purpose: Creating a holistic and differentiated view of how companies can manage and adapt to changing market conditions, thereby refining the field of research and offering new insights that can benefit both research and practice in the area. Research questions: (1) How does the case company Hestra Gloves address seasonal challenges within the textile industry, with a focus on inventory management and forecasting? (2) How does the fact of being a family-owned business influence Hestra Gloves in its resource allocation efforts, particularly regarding inventory? Method: The study is based on a qualitative research approach, where the empirical data has been collected through four carefully selected interviews within the case company. Theory: Consists of conceptual explanations and previous research related to the key terms. Furthermore, quantitative and qualitative methods for forecasting work are also presented. Conclusion: The case company manages demand changes through a combination of quantitative and qualitative forecasting methods. Despite the risk of high capital tie-up, the company chooses to maintain large inventories to ensure delivery during high demand, a strategy made possible by its family-owned structure and substantial equity.

Global warming poses an unprecedented threat to agroecosystems. Although temperature increases are more pronounced during winter than in other seasons, the impact of winter warming on crop biomass carbon has not been elucidated. Here we integrate global observational data with a decade-long field experiment to uncover a significant negative correlation between winter soil temperature and crop biomass carbon. For every degree Celsius increase in winter soil temperature, straw and grain biomass carbon decreased by 6.6 ( ± 1.7) g kg-1 and 10.2 ( ± 2.3) g kg-1, respectively. This decline is primarily attributed to the loss of soil organic matter and micronutrients induced by warming. Ignoring the adverse effects of winter warming on crop biomass carbon could result in an overestimation of total food production by 4% to 19% under future warming scenarios. Our research highlights the critical need to incorporate winter warming into agricultural productivity models for more effective climate adaptation strategies.

One of the activities of the Observatory of Veracruz Coffee Growing (OBSERVA-CAFÉ), is to follow up on the monitoring and generation of information on the agroclimatic conditions of coffee production systems in the state of Veracruz. Therefore, this work aimed to analyze the hygrothermometric conditions at different time scales in two shade-cast coffee production systems; 1) Café-Nacaxtle (CI) and 2) Café-Chalahuite (CE). On an annual scale, warmer and drier conditions were found in the CI production system compared to EC. On the scale of analysis by seasons, it is most evident during DEF (season December to February). In addition, according to the diurnal values of the DPV (vapor pressure deficit), coffee plants experience periods of water deficit during the March to May season (MAM), in both systems studied. This could help to plan specific mitigation strategies, according to the particular characteristics of each production system, during MAM., Una de las actividades del Observatorio de la Cafeticultura Veracruzana (OBSERVA-CAFÉ) es dar seguimiento al monitoreo y generación de información de las condiciones agroclimáticas de sistemas de producción de café del estado de Veracruz. Por lo que este trabajo tuvo como objetivo analizar las condiciones higrotermométricas, a diferentes escalas temporales, en dos sistemas de producción de café de café bajo sombra: 1) Café-Nacaxtle (CE) y 2) Café-Chalahuite (CI). Se encontró, a escala anual, condiciones más cálidas y secas en el sistema productivo CI en comparación con CE. En la escala de análisis por temporadas, es más evidente durante DEF (temporada diciembre a febrero). Además, de acuerdo con los valores diurnos del DPV (déficit de presión de vapor), las plantas de café en ambos sistemas estudiados experimentaron periodos de déficit hídrico durante la temporada marzo a mayo (MAM). Esto podría ayudar a planear estrategias de mitigación del déficit hídrico, de acuerdo con las características particulares de cada sistema productivo, durante MAM.

BACKGROUND: The interpretation of relative vaccine effectiveness (rVE) of improved influenza vaccines is complex. Estimation of burden averted is useful to contextualise their potential impact across different seasons. For the population aged under 65 years in Australia, this study estimated the additional morbidity and mortality that could be averted using improved influenza vaccines. METHODS: We used observed, season-specific (2015-2019) influenza notification and influenza-coded hospitalisation frequencies and published modelled estimates of influenza-associated hospitalisations and deaths that occurred under the prevailing influenza vaccination coverage scenario. After back-calculating to the estimated burden in the population without vaccination, we applied published standard influenza vaccine effectiveness and coverage estimates to calculate the burden potentially averted by standard and improved influenza vaccines. A plausible range of rVE values were used, assuming 50% coverage. RESULTS: The percentage point difference in absolute vaccine effectiveness (VE) of an improved vaccine compared to a standard vaccine is directly proportional to its rVE and inversely proportional to the effectiveness of the standard vaccine. The incremental burden averted by an improved vaccine is a function of both its difference in absolute VE and the severity of the influenza season. Assuming an rVE of 15% with 50% coverage, the improved vaccine was estimated to additionally avert 1517 to 12,641 influenza notifications, 287 to 1311 influenza-coded hospitalisations and 9 to 33 modelled all-cause influenza deaths per year compared to the standard vaccine. CONCLUSIONS: Improved vaccines can have substantial clinical and population impact, particularly when the effectiveness of standard vaccines is low, and burden is high.

Many animals and plants have species-typical annual cycles, but individuals vary in their timing of life-history events. Individual variation in fur replacement (moult) timing is poorly understood in mammals due to the challenge of repeated observations and longitudinal sampling. We examined factors that influence variation in moult duration and timing among elephant seals (Mirounga angustirostris). We quantified the onset and progression of fur loss in 1178 individuals. We found that an exceptionally rapid visible moult (7 days, the shortest of any mammals or birds), and a wide range of moult start dates (spanning 6-10× the event duration) facilitated high asynchrony across individuals (only 20% of individuals in the population moulting at the same time). Some of the variation was due to reproductive state, as reproductively mature females that skipped a breeding season moulted a week earlier than reproductive females. Moreover, individual variation in timing and duration within age-sex categories far outweighed (76-80%) variation among age-sex categories. Individuals arriving at the end of the moult season spent 50% less time on the beach, which allowed them to catch up in their annual cycles and reduce population-level variance during breeding. These findings underscore the importance of individual variation in annual cycles.

Wildfires are increasing in duration and intensity across the United States' Pacific West region, resulting in heightened particulate matter from smoke in the atmosphere. Levels of peak particulate matter are concurrent to peak visitor attendance at National Parks, given seasonal alignment with summer vacation travel and heightened forest fire conditions. Particulate matter threatens visitor health and safety and contributes to poor visibility and a deteriorated visitor experience. To assess visitation response to diminished air quality, we utilized wildfire-generated particulate matter (PM2.5) data in conjunction with monthly attendance records for three ecoregions containing eight national parks in Washington, Oregon, and California from 2009 to 2019. We analyzed daily PM2.5 levels from data gridded at the 10 km scale for National Park Service units by Level III forest ecoregions within the National Park Service's Pacific West Unit. Data were then compared to normalized monthly visitation trends for each of the ecoregions using two statistical methods Kendall's Tau and Analysis of Variance (ANOVA) with post-hoc Tukey tests. Results demonstrate that attendance at these national parks does not decrease in response to increased PM2.5 levels. Instead, we see several statistically significant increases in attendance across these ecoregions during periods of reduced air quality. Of 115 shifts between air quality categories during the busy season of July to September, there are no significant decreases in attendance as air quality worsens. These findings suggest that visitors are willing to tolerate reduced air quality compared to other factors such as temperature or precipitation. Given that park units within each ecoregion feature diverse historical contexts, varied built environments, and unique ecological systems, our discussion specifically addresses managerial concerns associated with maintained high levels of visitation during suboptimal, and potentially dangerous

BACKGROUND: As a primary vector of bluetongue virus (BTV) in the US, seasonal abundance and diel flight activity of Culicoides sonorensis has been documented, but few studies have examined how time of host-seeking activity is impacted by environmental factors. This knowledge is essential for interpreting surveillance data and modeling pathogen transmission risk. METHODS: The diel host-seeking activity of C. sonorensis was studied on a California dairy over 3 years using a time-segregated trap baited with CO2. The relationship between environmental variables and diel host-seeking activity (start, peak, and duration of activity) of C. sonorensis was evaluated using multiple linear regression. Fishers exact test and paired-sample z-test were used to evaluate the seasonal difference and parity difference on diel host-seeking activity. RESULTS: Host-seeking by C. sonorensis began and reached an activity peak before sunset at a higher frequency during colder months relative to warmer months. The time that host-seeking activity occurred was associated low and high daily temperature as well as wind speed at sunset. Colder temperatures and a greater diurnal temperature range were associated with an earlier peak in host-seeking. Higher wind speeds at sunset were associated with a delayed peak in host-seeking and a shortened duration of host-seeking. Parous midges reached peak host-seeking activity slightly later than nulliparous midges, possibly because of the need for oviposition by gravid females before returning to host-seeking. CONCLUSIONS: This study demonstrates that during colder months C. sonorensis initiates host-seeking and reaches peak host-seeking activity earlier relative to sunset, often even before sunset, compared to warmer months. Therefore, the commonly used UV light-baited traps are ineffective for midge surveillance before sunset. Based on this study, surveillance methods that do not rely on light trapping would provide a more accurate estimate of hos

Host-microbe interactions underlie the development and fitness of many macroorganisms, including bees. Whereas many social bees benefit from vertically transmitted gut bacteria, current data suggests that solitary bees, which comprise the vast majority of species diversity within bees, lack a highly specialized gut microbiome. Here, we examine the composition and abundance of bacteria and fungi throughout the complete life cycle of the ground-nesting solitary bee Anthophora bomboides standfordiana. In contrast to expectations, immature bee stages maintain a distinct core microbiome consisting of Actinobacterial genera (Streptomyces, Nocardiodes) and the fungus Moniliella spathulata. Dormant (diapausing) larval bees hosted the most abundant and distinctive bacteria and fungi, attaining 33 and 52 times their initial copy number, respectively. We tested two adaptive hypotheses regarding microbial functions for diapausing bees. First, using isolated bacteria and fungi, we found that Streptomyces from brood cells inhibited the growth of multiple pathogenic filamentous fungi, suggesting a role in pathogen protection during overwintering, when bees face high pathogen pressure. Second, sugar alcohol composition changed in tandem with major changes in fungal abundance, suggesting links with bee cold tolerance or overwintering biology. We find that A. bomboides hosts a conserved core microbiome that may provide key fitness advantages through larval development and diapause, which raises the question of how this microbiome is maintained and faithfully transmitted between generations. Our results suggest that focus on microbiomes of mature or active insect developmental stages may overlook stage-specific symbionts and microbial fitness contributions during host dormancy.

First-ever measurements of particulate matter (PM2.5, PM10, and TSP) along with gaseous pollutants (CO, NO2, and SO2) were performed from June 2019 to April 2020 in Faisalabad, Metropolitan, Pakistan, to assess their seasonal variations; Summer 2019, Autumn 2019, Winter 2019-2020, and Spring 2020. Pollutant measurements were carried out at 30 locations with a 3-km grid distance from the Sitara Chemical Industry in District Faisalabad to Bhianwala, Sargodha Road, Tehsil Lalian, District Chiniot. ArcGIS 10.8 was used to interpolate pollutant concentrations using the inverse distance weightage method. PM2.5, PM10, and TSP concentrations were highest in summer, and lowest in autumn or winter. CO, NO2, and SO2 concentrations were highest in summer or spring and lowest in winter. Seasonal average NO2 and SO2 concentrations exceeded WHO annual air quality guide values. For all 4 seasons, some sites had better air quality than others. Even in these cleaner sites air quality index (AQI) was unhealthy for sensitive groups and the less good sites showed Very critical AQI (> 500). Dust-bound carbon and sulfur contents were higher in spring (64 mg g-1) and summer (1.17 mg g-1) and lower in autumn (55 mg g-1) and winter (1.08 mg g-1). Venous blood analysis of 20 individuals showed cadmium and lead concentrations higher than WHO permissible limits. Those individuals exposed to direct roadside pollution for longer periods because of their occupation tended to show higher Pb and Cd blood concentrations. It is concluded that air quality along the roadside is extremely poor and potentially damaging to the health of exposed workers.

Global warming modulates soil respiration (RS) via microbial decomposition, which is seasonally dependent. Yet, the magnitude and direction of this modulation remain unclear, partly owing to the lack of knowledge on how microorganisms respond to seasonal changes. Here, we investigated the temporal dynamics of soil microbial communities over 12 consecutive months under experimental warming in a tallgrass prairie ecosystem. The interplay between warming and time altered (P < 0.05) the taxonomic and functional compositions of microbial communities. During the cool months (January to February and October to December), warming induced a soil microbiome with a higher genomic potential for carbon decomposition, community-level ribosomal RNA operon (rrn) copy numbers, and microbial metabolic quotients, suggesting that warming stimulated fast-growing microorganisms that enhanced carbon decomposition. Modeling analyses further showed that warming reduced the temperature sensitivity of microbial carbon use efficiency (CUE) by 28.7% when monthly average temperature was low, resulting in lower microbial CUE and higher heterotrophic respiration (Rh) potentials. Structural equation modeling showed that warming modulated both Rh and RS directly by altering soil temperature and indirectly by influencing microbial community traits, soil moisture, nitrate content, soil pH, and gross primary productivity. The modulation of Rh by warming was more pronounced in cooler months compared to warmer ones. Together, our findings reveal distinct warming-induced effects on microbial functional traits in cool months, challenging the norm of soil sampling only in the peak growing season, and advancing our mechanistic understanding of the seasonal pattern of RS and Rh sensitivity to warming.

Organisms adapt to unfavorable seasonal conditions to survive. These seasonal adaptations rely on the correct interpretation of environmental cues such as photoperiod, and temperature. Genetic studies in several organisms, including the genetic powerhouse Drosophila melanogaster, indicate that circadian clock components, such as period and timeless, are involved in photoperiodic-dependent seasonal adaptations, but our understanding of this process is far from complete. In particular, the role of temperature as a key factor to complement photoperiodic response is not well understood. The development of new sequencing technologies has proven extremely useful in understanding the plastic changes that the clock and other cellular components undergo in different environmental conditions, including changes in gene expression and alternative splicing. This article discusses the integration of photoperiod and temperature for seasonal biology as well as downstream molecular and cellular pathways involved in the regulation of physiological adaptations that occur with changing seasons. We focus our discussion on the current understanding of the involvement of the molecular clock and the circadian clock neuronal circuits in these adaptations in D. melanogaster.

Sperm whales exhibit sexual dimorphism and sex-specific latitudinal segregation. Females and their young form social groups and are usually found in temperate and tropical latitudes, while males forage at higher latitudes. Historical whaling data and rare sightings of social groups in high latitude regions of the North Pacific, such as the Gulf of Alaska (GOA) and Bering Sea/Aleutian Islands (BSAI), suggest a more complex distribution than previously understood. Sperm whales are the most sighted and recorded cetacean in marine mammal surveys in these regions but capturing their demographic composition and habitat use has proven challenging. This study detects sperm whale presence using passive acoustic data from seven sites in the GOA and BSAI from 2010 to 2019. Differences in click characteristics between males and females (i.e., inter-click and inter-pulse interval) was used as a proxy for animal size/sex to derive time series of animal detections. Generalized additive models with generalized estimation equations demonstrate how spatiotemporal patterns differ between the sexes. Social groups were present at all recording sites with the largest relative proportion at two seamount sites in the GOA and an island site in the BSAI. We found that the seasonal patterns of presence varied for the sexes and between the sites. Male presence was highest in the summer and lowest in the winter, conversely, social group peak presence was in the winter for the BSAI and in the spring for the GOA region, with the lowest presence in the summer months. This study demonstrates that social groups are not restricted to lower latitudes and capture their present-day habitat use in the North Pacific. It highlights that sperm whale distribution is more complex than accounted for in management protocol and underscores the need for improved understanding of sperm whale demographic composition to better understand the impacts of increasing anthropogenic threats, particularly climate change.

Climate change reduces snowpack, advances snowmelt phenology, drives summer warming, alters growing season precipitation regimes, and consequently modifies vegetation phenology in mountain systems. Elevational migrants track spatial variation in seasonal plant growth by moving between ranges at different elevations during spring, so climate-driven vegetation change may disrupt historic benefits of migration. Elevational migrants can furthermore cope with short-term environmental variability by undertaking brief vertical movements to refugia when sudden adverse conditions arise. We uncover drivers of fine-scale vertical movement variation during upland migration in an endangered alpine specialist, Sierra Nevada bighorn sheep (Ovis canadensis sierrae) using a 20-year study of GPS collar data collected from 311 unique individuals. We used integrated step-selection analysis to determine factors that promote vertical movements and drive selection of destinations following vertical movements. Our results reveal that relatively high temperatures consistently drive uphill movements, while precipitation likely drives downhill movements. Furthermore, bighorn select destinations at their peak annual biomass and maximal time since snowmelt. These results indicate that although Sierra Nevada bighorn sheep seek out foraging opportunities related to landscape phenology, they compensate for short-term environmental stressors by undertaking brief up- and downslope vertical movements. Migrants may therefore be impacted by future warming and increased storm frequency or intensity, with shifts in annual migration timing, and fine-scale vertical movement responses to environmental variability.

Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5.

Soil desertification poses a critical ecological challenge in arid and semiarid climates worldwide, leading to decreased soil productivity due to the disruption of essential microbial community processes. Fungi, as one of the most important soil microbial communities, play a crucial role in enhancing nutrient and water uptake by plants through mycorrhizal associations. However, the impact of overgrazing-induced desertification on fungal community structure, particularly in the Caatinga biome of semiarid regions, remains unclear. In this study, we assessed the changes in both the total fungal community and the arbuscular mycorrhizal fungal community (AMF) across 1. Natural vegetation (native), 2. Grazing exclusion (20 years) (restored), and 3. affected by overgrazing-induced degradation (degraded) scenarios. Our assessment, conducted during both the dry and rainy seasons in Irauçuba, Ceará, utilized Internal Transcribed Spacer (ITS) gene sequencing via Illumina® platform. Our findings highlighted the significant roles of the AMF families Glomeraceae (∼71% of the total sequences) and Acaulosporaceae (∼14% of the total sequences) as potential key taxa in mitigating climate change within dryland areas. Moreover, we identified the orders Pleosporales (∼35% of the total sequences) and Capnodiales (∼21% of the total sequences) as the most abundant soil fungal communities in the Caatinga biome. The structure of the total fungal community differed when comparing native and restored areas to degraded areas. Total fungal communities from native and restored areas clustered together, suggesting that grazing exclusion has the potential to improve soil properties and recover fungal community structure amid global climate change challenges.

Peer Reviewed

Bioenergetic constraints are the ultimate determinant of the timing of reproduction, and seasonal breeding is consequently a widely observed trait. Consistent with this, attention has focused on plasticity in reproductive phenology conceptualized as a response to concomitant advances in the phenology of the environmental energy supply caused by climate change. Few studies, however, have directly compared timing of reproduction with energetic status in free-living wild animals. Here we demonstrate that neither body mass nor adiposity are strong proximate predictors of date of conception in wild reindeer (Rangifer tarandus). Weak coupling between energetic status and the phenology of reproduction accounts for the increasing discrepancy between the phenology of forage (energy supply) and the phenology of reproduction (energy demand) observed across the last 2-4 decades in two populations of this species. The results emphasise that phenological plasticity is not a passive response to changes in energy supply but derives from the way in which environmental factors interact with the core control mechanisms that govern timing. Central in this respect is integration, within the rheostatic centres of the hypothalamus, of information on nutritional status with the circannual life-history calendar.

In deze uitgave: De inrichting van de tuin biedt genoeg mogelijkheden om er later volop van te kunnen genieten; enkele tips. Een groene tuin is niet alleen aantrekkelijker, maar de aanleg is goedkoper dan bij een tuin met veel tegels; we geven enkele rekenvoorbeelden. Een groene tuin, dus met planten, struiken en bomen, is belangrijk voor onze gezondheid. Uit wetenschappelijk onderzoek is vast komen te staan dat voor vrij veel aandoeningen een tuin gunstig blijkt te zijn.

The collaborative thesis with the Swedish Geotechnical Institute (SGI) investigates seasonal PFAS contamination spreading near Örnsköldsvik airport, where AFFF was used during fire drills from 1993 to 2008. Data analysis of 11 PFAS concentrations from November 2022 to October 2023 utilized scatterplots and time series graphs. In ArcMap, concentrations were interpolated to predict spatial spreading across four seasons. Geologically, the area features an upper aquifer confined by a clay layer, potentially with a lower aquifer. High PFAS concentrations in the upper aquifer occur during spring and autumn, except for PFHxA and PFBA, peaking in winter. Contamination primarily extends towards Varmyrän, with unexpected spread towards Bromyrän and the northeast area to the fire drill site. Significant spatial changes occur from winter to spring, and certain short-chain PFAS behave similarly in time and space. Limited data for the lower aquifer allowed analysis only during summer and autumn, revealing major spatial changes concentrated in the north of the fire drill area. In both layers, PFOS, PFHxS, and PFHxA present the highest concentration. Various factors influence PFAS movement, including groundwater levels, soil types, and precipitation, with seasonal groundwater data lacking. PFOS and PFHxS move towards Varmyrän within approximately 30 days, with additional movement towards the airport. Percolation from the upper to the lower aquifer could take around six months, with data limitations for winter and spring in the lower aquifer. Kriging is sensitive to point quantity, and normalization complicates absolute value comparisons from interpolations. This study highlights the need for comprehensive data collection, alternative methodologies for studying PFAS seasonal changes, and improved data visualization techniques to enhance understanding of PFAS dynamics in the groundwater., Samarbetet med Statens geotekniska institut (SGI) undersöker säsongsbunden PFAS-föroreningsspridning nära Örnsköldsviks flygplats, där AFFF användes under brandövningar från 1993 till 2008. Dataanalys av 11 PFAS-koncentrationer från november 2022 till oktober 2023 använde scattergraphs och tidsseriediagram. . I ArcMap interpolerades koncentrationer för att förutsäga rumslig spridning över fyra årstider. Geologiskt har området en övre akvifär som är begränsad av ett lerlager, potentiellt med en lägre akvifär. Höga PFAS-koncentrationer i den övre akvifären förekommer under våren och hösten, förutom PFHxA och PFBA, som toppar på vintern. Föroreningarna sträcker sig i första hand mot Varmyrän, med oväntad spridning mot Bromyrän och det nordöstra området till brandövningsplatsen. Betydande rumsliga förändringar sker från vinter till vår, och vissa kortkedjiga PFAS uppträder på liknande sätt i tid och rum. Begränsade data för den nedre akvifären möjliggjorde analys endast under sommaren och hösten, vilket avslöjade stora rumsliga förändringar koncentrerade till norra delen av brandövningsområdet. I båda skikten har PFOS, PFHxS och PFHxA den högsta koncentrationen. Olika faktorer påverkar PFAS-rörelsen, inklusive grundvattennivåer, jordtyper och nederbörd, med säsongsbetonade grundvattendata saknas. PFOS och PFHxS rör sig mot Varmyrän inom cirka 30 dagar, med ytterligare förflyttning mot flygplatsen. Perkolering från den övre till den nedre akvifären kan ta cirka sex månader, med databegränsningar för vinter och vår i den nedre akvifären. Kriging är känsligt för punktkvantitet, och normalisering komplicerar absolutvärdesjämförelser från interpolationer. Denna studie belyser behovet av omfattande datainsamling, alternativa metoder för att studera PFAS säsongsförändringar och förbättrade datavisualiseringstekniker för att öka förståelsen för PFAS-dynamiken i grundvattnet.

Syfte: Att skapa en holistisk och differentierad bild av hur företag kan hantera och anpassa sig till föränderliga marknadsförhållanden och därigenom nyansera forskningsfältet och erbjuda nya insikter som kan gynna både forskning och praktiken inom området. Forskningsfrågor: (1) Hur arbetar fallföretaget Hestra Gloves med de säsongsbaserade utmaningarna inom textilindustrin med fokus på lagerhantering och prognostisering? (2) Hur påverkar det faktumet att vara ett familjeägt företag Hestra Gloves i sitt arbete med resursallokering, med fokus på lager? Metod: Studien utgår från en kvalitativ forskningsansats där det empiriska materialet har insamlats genom fyra noggrant valda intervjuer från fallföretaget. Teori: Består av begreppsförklaring och tidigare forskning som berör nyckelorden. Vidare presenteras även kvantitativa och kvalitativa metoder för prognostiseringsarbete. Slutsats: Fallföretaget hanterar efterfrågeförändringar genom en kombination av kvantitativa och kvalitativa prognosmetoder. Trots risken med hög kapitalbindning väljer företaget att hålla stora lager för att säkerställa leverans vid hög efterfrågan, en strategi möjliggjord av dess familjeägda struktur och stora eget kapital., Purpose: Creating a holistic and differentiated view of how companies can manage and adapt to changing market conditions, thereby refining the field of research and offering new insights that can benefit both research and practice in the area. Research questions: (1) How does the case company Hestra Gloves address seasonal challenges within the textile industry, with a focus on inventory management and forecasting? (2) How does the fact of being a family-owned business influence Hestra Gloves in its resource allocation efforts, particularly regarding inventory? Method: The study is based on a qualitative research approach, where the empirical data has been collected through four carefully selected interviews within the case company. Theory: Consists of conceptual explanations and previous research related to the key terms. Furthermore, quantitative and qualitative methods for forecasting work are also presented. Conclusion: The case company manages demand changes through a combination of quantitative and qualitative forecasting methods. Despite the risk of high capital tie-up, the company chooses to maintain large inventories to ensure delivery during high demand, a strategy made possible by its family-owned structure and substantial equity.

The collaborative thesis with the Swedish Geotechnical Institute (SGI) investigates seasonal PFAS contamination spreading near Örnsköldsvik airport, where AFFF was used during fire drills from 1993 to 2008. Data analysis of 11 PFAS concentrations from November 2022 to October 2023 utilized scatterplots and time series graphs. In ArcMap, concentrations were interpolated to predict spatial spreading across four seasons. Geologically, the area features an upper aquifer confined by a clay layer, potentially with a lower aquifer. High PFAS concentrations in the upper aquifer occur during spring and autumn, except for PFHxA and PFBA, peaking in winter. Contamination primarily extends towards Varmyrän, with unexpected spread towards Bromyrän and the northeast area to the fire drill site. Significant spatial changes occur from winter to spring, and certain short-chain PFAS behave similarly in time and space. Limited data for the lower aquifer allowed analysis only during summer and autumn, revealing major spatial changes concentrated in the north of the fire drill area. In both layers, PFOS, PFHxS, and PFHxA present the highest concentration. Various factors influence PFAS movement, including groundwater levels, soil types, and precipitation, with seasonal groundwater data lacking. PFOS and PFHxS move towards Varmyrän within approximately 30 days, with additional movement towards the airport. Percolation from the upper to the lower aquifer could take around six months, with data limitations for winter and spring in the lower aquifer. Kriging is sensitive to point quantity, and normalization complicates absolute value comparisons from interpolations. This study highlights the need for comprehensive data collection, alternative methodologies for studying PFAS seasonal changes, and improved data visualization techniques to enhance understanding of PFAS dynamics in the groundwater., Samarbetet med Statens geotekniska institut (SGI) undersöker säsongsbunden PFAS-föroreningsspridning nära Örnsköldsviks flygplats, där AFFF användes under brandövningar från 1993 till 2008. Dataanalys av 11 PFAS-koncentrationer från november 2022 till oktober 2023 använde scattergraphs och tidsseriediagram. . I ArcMap interpolerades koncentrationer för att förutsäga rumslig spridning över fyra årstider. Geologiskt har området en övre akvifär som är begränsad av ett lerlager, potentiellt med en lägre akvifär. Höga PFAS-koncentrationer i den övre akvifären förekommer under våren och hösten, förutom PFHxA och PFBA, som toppar på vintern. Föroreningarna sträcker sig i första hand mot Varmyrän, med oväntad spridning mot Bromyrän och det nordöstra området till brandövningsplatsen. Betydande rumsliga förändringar sker från vinter till vår, och vissa kortkedjiga PFAS uppträder på liknande sätt i tid och rum. Begränsade data för den nedre akvifären möjliggjorde analys endast under sommaren och hösten, vilket avslöjade stora rumsliga förändringar koncentrerade till norra delen av brandövningsområdet. I båda skikten har PFOS, PFHxS och PFHxA den högsta koncentrationen. Olika faktorer påverkar PFAS-rörelsen, inklusive grundvattennivåer, jordtyper och nederbörd, med säsongsbetonade grundvattendata saknas. PFOS och PFHxS rör sig mot Varmyrän inom cirka 30 dagar, med ytterligare förflyttning mot flygplatsen. Perkolering från den övre till den nedre akvifären kan ta cirka sex månader, med databegränsningar för vinter och vår i den nedre akvifären. Kriging är känsligt för punktkvantitet, och normalisering komplicerar absolutvärdesjämförelser från interpolationer. Denna studie belyser behovet av omfattande datainsamling, alternativa metoder för att studera PFAS säsongsförändringar och förbättrade datavisualiseringstekniker för att öka förståelsen för PFAS-dynamiken i grundvattnet.

A short take on the pros and cons associated with daylight saving time

Seasonal malaria chemoprevention (SMC) by mass administration of sulfadoxine pyrimethamine + amodiaquine (SPAQ) reduces the burden of malaria in children aged 3–59 months. The occurrence of adverse drug reaction (ADR) may affect the success of this intervention. There are few studies of SMC adverse event surveillance in sub-Saharan Africa, particularly in Burkina Faso, a highly endemic country. Our main objective was to characterize the ADRs reported during SMC campaigns in Burkina Faso. Secondly, we evaluated the performance of the pharmacovigilance integrated into the SMC program in order to support safe administration of SMC., SCOPUS: ar.j, info:eu-repo/semantics/published

A short take on the pros and cons associated with daylight saving time

Climate change is affecting the phenology of organisms and ecosystem processes across a wide range of environments. However, the links between organismal and ecosystem process change in complex communities remain uncertain. In snow-dominated watersheds, snowmelt in the spring and early summer, followed by a long low-flow period, characterizes the natural flow regime of streams and rivers. Here, we examined how earlier snowmelt will alter the phenology of mountain stream organisms and ecosystem processes via an outdoor mesocosm experiment in stream channels in the Eastern Sierra Nevada, California. The low-flow treatment, simulating a 3- to 6-wk earlier return to summer baseflow conditions projected under climate change scenarios in the region, increased water temperature and reduced biofilm production to respiration ratios by 32%. Additionally, most of the invertebrate species explaining community change (56% and 67% of the benthic and emergent taxa, respectively), changed in phenology as a consequence of the low-flow treatment. Further, emergent flux pulses of the dominant insect group (Chironomidae) almost doubled in magnitude, benefitting a generalist riparian predator. Changes in both invertebrate community structure (composition) and functioning (production) were mostly fine-scale, and response diversity at the community level stabilized seasonally aggregated responses. Our study illustrates how climate change in vulnerable mountain streams at the rain-to-snow transition is poised to alter the dynamics of stream food webs via fine-scale changes in phenology-leading to novel predator-prey matches or mismatches even when community structure and ecosystem processes appear stable at the annual scale.

Understanding the topographic basis for microclimatic variation remains fundamental to predicting the site level effects of warming air temperatures. Quantifying diurnal fluctuation and seasonal extremes in relation to topography offers insight into the potential relationship between site level conditions and changes in regional climate. The present study investigated an annual understory temperature regime for 50 sites distributed across a topographically diverse area (>12 km2) comprised of mixed evergreen-deciduous woodland vegetation typical of California coastal ranges. We investigated the effect of topography and tree cover on site-to-site variation in near-surface temperatures using a combination of multiple linear regression and multivariate techniques. Sites in topographically depressed areas (e.g., valley bottoms) exhibited larger seasonal and diurnal variation. Elevation (at 10 m resolution) was found to be the primary driver of daily and seasonal variations, in addition to hillslope position, canopy cover and northness. The elevation effect on seasonal mean temperatures was inverted, reflecting large-scale cold-air pooling in the study region, with elevated minimum and mean temperature at higher elevations. Additionally, several of our sites showed considerable buffering (dampened diurnal and seasonal temperature fluctuations) compared to average regional conditions measured at an on-site weather station. Results from this study help inform efforts to extrapolate temperature records across large landscapes and have the potential to improve our ecological understanding of fine-scale seasonal climate variation in coastal range environments.

To accurately predict species’ phenology under climate change, we need to gain a detailed mechanistic understanding of how different environmental cues interact to produce the seasonal timing response. In the winter moth (Operophtera brumata), seasonal timing of egg hatching is strongly affected by ambient temperature and has been under strong climate change-induced selection over the past 25 years. However, it is unclear whether photoperiod received at the egg stage also influences timing of egg hatching. Here, we investigated the relative contribution of photoperiod and temperature in regulating winter moth egg development using two split-brood experiments. We experimentally shifted the photoperiod eggs received by 2–4 weeks compared to the actual calendar date and measured the timing of egg hatching, both at a constant temperature and in combination with two naturally changing temperature treatments – mimicking a cold and a warm year. We found an eight-fold larger effect of temperature compared to photoperiod on egg development time. Moreover, the very small photoperiod effects we found were outweighed by both between- and within-clutch variation in egg development time. Thus, we conclude that photoperiod received at the egg stage does likely not play a substantial role in regulating the seasonal timing of egg hatching in the winter moth. These insights into the regulatory mechanism of seasonal timing could have important implications for predicting insect climate change adaptation, as we might expect different targets of selection depending on the relative contribution of different environmental cues.

Background: In malaria endemic regions, transmission of Plasmodium falciparum parasites is often seasonal with very low transmission during the dry season and high transmission in the wet season. Parasites survive the dry season within some individuals who experience prolonged carriage of parasites and are thought to ‘seed’ infection in the next transmission season. Methods: Dry season carriers and their role in the subsequent transmission season are characterized using a combination of mathematical simulations and data analysis of previously described data from a longitudinal study in Mali of individuals aged 3 months–12 years (n = 579). Results: Simulating the life-history of individuals experiencing repeated exposure to infection predicts that dry season carriage is more likely in the oldest, most exposed and most immune individuals. This hypothesis is supported by the data from Mali, which shows that carriers are significantly older, experience a higher biting rate at the beginning of the transmission season and develop clinical malaria later than non-carriers. Further, since the most exposed individuals in a community are most likely to be dry season carriers, this is predicted to enable a more than twofold faster spread of parasites into the mosquito population at the start of the subsequent wet season. Conclusions: Carriage of malaria parasites over the months-long dry season in Mali is most likely in the older, more exposed and more immune children. These children may act as super-spreaders facilitating the fast spread of parasites at the beginning of the next transmission season.

Background: The South African government employed various nonpharmaceutical interventions (NPIs) to reduce the spread of SARS-CoV-2. Surveillance data from South Africa indicates reduced circulation of respiratory syncytial virus (RSV) throughout the 2020–2021 seasons. Here, we use a mechanistic transmission model to project the rebound of RSV in the two subsequent seasons. Methods: We fit an age-structured epidemiological model to hospitalization data from national RSV surveillance in South Africa, allowing for time-varying reduction in RSV transmission during periods of COVID-19 circulation. We apply the model to project the rebound of RSV in the 2022 and 2023 seasons. Results: We projected an early and intense outbreak of RSV in April 2022, with an age shift to older infants (6–23 months old) experiencing a larger portion of severe disease burden than typical. In March 2022, government alerts were issued to prepare the hospital system for this potentially intense outbreak. We then assess the 2022 predictions and project the 2023 season. Model predictions for 2023 indicate that RSV activity has not fully returned to normal, with a projected early and moderately intense wave. We estimate that NPIs reduced RSV transmission between 15% and 50% during periods of COVID-19 circulation. Conclusions: A wide range of NPIs impacted the dynamics of the RSV outbreaks throughout 2020–2023 in regard to timing, magnitude, and age structure, with important implications in a low- and middle-income countries (LMICs) setting where RSV interventions remain limited. More efforts should focus on adapting RSV models to LMIC data to project the impact of upcoming medical interventions for this disease.

The relative arrival time of species can affect their interactions and thus determine which species persist in a community. Although this phenomenon, called priority effect, is widespread in natural communities, it is unclear how it depends on the length of growing season. Using a seasonal stage-structured model, we show that differences in stages of interacting species could generate priority effects by altering the strength of stabilizing and equalizing coexistence mechanisms, changing outcomes between exclusion, coexistence and positive frequency dependence. However, these priority effects are strongest in systems with just one or a few generations per season and diminish in systems where many overlapping generations per season dilute the importance of stage-specific interactions. Our model reveals a novel link between the number of generations in a season and the consequences of priority effects, suggesting that consequences of phenological shifts driven by climate change should depend on specific life histories of organisms.

In March-June 2023, we conducted a test-negative study in 1671 children who were hospitalized with acute respiratory illness in Hong Kong. Two hundred and eighty-six children (17.2%) were tested positive for influenza virus including 188 with A(H1N1). We estimated influenza vaccine effectiveness against influenza-associated hospitalization as 69.6% (95% confidence interval: 49.3%, 81.7%).

We estimated the effectiveness of influenza vaccines in preventing laboratory-confirmed influenza among older adults in aged care. Electronic database searches were conducted using search terms, and studies were selected as per the selection criteria. Fourteen studies were included for final review. The studies exhibited considerable variation in reported vaccine effectiveness (VE) across different seasons. Among the observational studies, VE ranged from 7.2% to 89.8% against laboratory-confirmed influenza across different vaccines. Randomized clinical trials demonstrated a 17% reduction in infection rates with the adjuvanted trivalent vaccine. The limitations include the small number of included studies conducted in different countries or regions, varied seasons, variations in diagnostic testing methods, a focus on the A/H3N2 strain, and few studies available on the effectiveness of enhanced influenza vaccines in aged care settings. Despite challenges associated with achieving optimal protection, the studies showed the benefits of influenza vaccination in the elderly residents.

BACKGROUND: Season of birth has been associated with age at menarche. Maternal vitamin D levels in pregnancy may explain this effect. We investigated whether the season of first trimester or maternal 25-hydroxyvitamin D3 [25(OH)D3] levels were associated with pubertal timing in children. METHODS: We conducted a follow-up study of 15 819 children born in 2000-03 from the Puberty Cohort, nested in the Danish National Birth Cohort (DNBC). Mean differences in attaining numerous pubertal markers, including a combined estimate for the average age at attaining all pubertal markers, were estimated for low (November-April) relative to high (May-October) sunshine exposure season in the first trimester using multivariable interval-censored regression models. Moreover, we conducted a two-sample instrumental variable analysis using season as an instrument for maternal first-trimester 25(OH)D3 plasma levels obtained from a non-overlapping subset (n = 827) in the DNBC. RESULTS: For the combined estimate, girls and boys of mothers who had their first trimester during November-April had earlier pubertal timing than girls and boys of mothers whose first trimester occurred during May-October: -1.0 months (95% CI: -1.7 to -0.3) and -0.7 months (95% CI: -1.4 to -0.1), respectively. In the instrumental variable analysis, girls and boys also had earlier pubertal timing: respectively, -1.3 months (95% CI: -2.1 to -0.4) and -1.0 months (95% CI: -1.8 to -0.2) per SD (22 nmol/L) decrease in 25(OH)D3. CONCLUSIONS: Both first pregnancy trimester during November-April and lower 25(OH)D3 were associated with earlier pubertal timing in girls and boys.

BACKGROUND: Despite scale-up of seasonal malaria chemoprevention (SMC) with sulfadoxine-pyrimethamine and amodiaquine (SP-AQ) in children 3-59 months of age in Burkina Faso, malaria incidence remains high, raising concerns regarding SMC effectiveness and selection of drug resistance. Using a case-control design, we determined associations between SMC drug levels, drug resistance markers, and presentation with malaria. METHODS: We enrolled 310 children presenting at health facilities in Bobo-Dioulasso. Cases were SMC-eligible children 6-59 months of age diagnosed with malaria. Two controls were enrolled per case: SMC-eligible children without malaria; and older (5-10 years old), SMC-ineligible children with malaria. We measured SP-AQ drug levels among SMC-eligible children and SP-AQ resistance markers among parasitemic children. Conditional logistic regression was used to compute odds ratios (ORs) comparing drug levels between cases and controls. RESULTS: Compared to SMC-eligible controls, children with malaria were less likely to have any detectable SP or AQ (OR, 0.33 [95% confidence interval, .16-.67]; P = .002) and have lower drug levels (P < .05). Prevalences of mutations mediating high-level SP resistance were rare (0%-1%) and similar between cases and SMC-ineligible controls (P > .05). CONCLUSIONS: Incident malaria among SMC-eligible children was likely due to suboptimal levels of SP-AQ, resulting from missed cycles rather than increased antimalarial resistance to SP-AQ.

Nest defense in the honey bee (Apis mellifera) is a complex collective behavior modulated by various interacting social, environmental, and genetic factors. Scutellata-hybrid ("Africanized") honey bees are usually considered to be far more defensive than European honey bees which are therefore preferred for commercial and hobbyist beekeeping. In the most recent zone of scutellata hybridization, the southern USA, the degree to which this defensiveness differs among current strains, and the extent to which defensiveness varies across a season has not been measured. We quantified the levels of A. m. scutellata ancestry in colonies and conducted a seasonal assessment (May through November) of colony nest defensiveness in feral scutellata-hybrid and a popular lineage of European honey bee commonly used in managed environments (sold as A. mellifera ligustica) hives at two apiaries in Southern California. Standard measures of defensiveness were low in both scutellata-hybrid and European colonies during May. Defensiveness increased during the later months of the study in scutellata-hybrid colonies. Most measures of defensiveness did not increase in managed colonies. Defensiveness in the scutellata-hybrids appears lower than what has been previously documented in Brazil and Mexico, possibly due to their lower proportion of A. m. scutellata ancestry.

For social animals, group social structure has important consequences for disease and information spread. While prior studies showed individual connectedness within a group has fitness consequences, less is known about the fitness consequences of group social structure for the individuals who comprise the group. Using a long-term dataset on a wild population of facultatively social yellow-bellied marmots (Marmota flaviventer), we showed social structure had largely no relationship with survival, suggesting consequences of individual social phenotypes may not scale to the group social phenotype. An observed relationship for winter survival suggests a potentially contrasting direction of selection between the group and previous research on the individual level; less social individuals, but individuals in more social groups experience greater winter survival. This work provides valuable insights into evolutionary implications across social phenotypic scales.

Population cycles have been observed in mammals as well as insects, but consistent population cycling has rarely been documented in agroecosystems and never for a beetle. We analysed the long-term population patterns of the cabbage stem flea beetle Psylliodes chrysocephala in winter oilseed rape over 50 years. Psylliodes chrysocephala larval density from 3045 winter oilseed rape fields in southern Sweden showed strong 8-year population cycles in regional mean density. Fluctuations in larval density were synchronous over time across five subregional populations. Subregional mean environmental variables explained 90.6% of the synchrony in P. chrysocephala populations at the 7-11 year time-scale. The number of days below -10°C showed strong anti-phase coherence with larval densities in the 7-11 year time-scale, such that more cold days resulted in low larval densities. High levels of the North Atlantic Oscillation weather system are coherent and anti-phase with cold weather in Scania, Sweden. At the field-scale, later crop planting date and more cold winter days were associated with decreased overwintering larval density. Warmer autumn temperatures, resulting in greater larval accumulated degree days early in the season, increased overwintering larval density. Despite variation in environmental conditions and crop management, 8-year cycles persisted for cabbage stem flea beetle throughout the 50 years of data collection. Moran effects, influenced by the North Atlantic Oscillation weather patterns, are the primary drivers of this cycle and synchronicity. Insect pest data collected in commercial agriculture fields is an abundant source of long-term data. We show that an agricultural pest can have the same periodic population cycles observed in perennial and unmanaged ecosystems. This unexpected finding has implications for sustainable pest management in agriculture and shows the value of long-term pest monitoring projects as an additional source of time-se

Traits that mediate reproductive isolation between species, such as those involved in mate choice and/or recognition, are predicted to experience stabilizing selection towards the species mean. Male orchid bees collect chemical compounds from many sources, such as plants and fungi, which they use as a perfume signal (pheromone) during courtship display, and are suggested to contribute to reproductive isolation between species. Environmentally acquired signals are more prone to variation as source availability can vary through space and time. If orchid bee perfumes are important for reproductive isolation between species, we expect them to exhibit stable species-specific differences in time and space. Here, we describe phenotypic patterns of inter- and intraspecific variation in the male perfumes of three sympatric species of Euglossa orchid bees across an entire year, investigating both their seasonality and species specificity. Our analysis revealed considerable within-species variation in perfumes. However, species specificity was maintained consistently throughout the year, supporting the idea that these perfumes could play an important role in reproductive isolation and are experiencing stabilizing selection towards a species mean. Our analysis also identified strong correlations in the abundance of some compounds, possibly due to shared collection sources between species. Our study suggests that orchid bee perfumes are robust in the face of environmental changes in resource availability and thus can maintain reproductive isolation between species.

Background: Cold winter weather increases the risk of stroke, but the evidence is scarce on whether the risk increases during season-specific cold weather in the other seasons. The objective of our study was to test the hypothesis of an association between personal cold spells and different types of stroke in the season-specific context, and to formally assess effect modification by age and sex. Methods: We conducted a case-crossover study of all 5396 confirmed 25–64 years old cases with stroke in the city of Kaunas, Lithuania, 2000–2015. We assigned to each case a one-week hazard period and 15 reference periods of the same calendar days of other study years. A personal cold day was defined for each case with a mean temperature below the fifth percentile of the frequency distribution of daily mean temperatures of the hazard and reference periods. Conditional logistic regression was applied to estimate odds ratios (OR) and 95% confidence intervals (95% CI) representing associations between time- and place-specific cold weather and stroke. Results: There were positive associations between cold weather and stroke in Kaunas, with each additional cold day during the week before the stroke increases the risk by 3% (OR 1.03; 95% CI 1.00–1.07). The association was present for ischemic stroke (OR 1.05; 95% CI 1.01–1.09) but not hemorrhagic stroke (OR 0.98; 95% CI 0.91–1.06). In the summer, the risk of stroke increased by 8% (OR 1.08; 95% CI 1.00–1.16) per each additional cold day during the hazard period. Age and sex did not modify the effect. Conclusions: Our findings show that personal cold spells increase the risk of stroke, and this pertains to ischemic stroke specifically. Most importantly, cold weather in the summer season may be a previously unrecognized determinant of stroke.

Gross primary production (GPP) by terrestrial ecosystems is a key quantity in the global carbon cycle. The instantaneous controls of leaf-level photosynthesis are well established, but there is still no consensus on the mechanisms by which canopy-level GPP depends on spatial and temporal variation in the environment. The standard model of photosynthesis provides a robust mechanistic representation for C3 species; however, additional assumptions are required to "scale up" from leaf to canopy. As a consequence, competing models make inconsistent predictions about how GPP will respond to continuing environmental change. This problem is addressed here by means of an empirical analysis of the light use efficiency (LUE) of GPP inferred from eddy covariance carbon dioxide flux measurements, in situ measurements of photosynthetically active radiation (PAR), and remotely sensed estimates of the fraction of PAR (fAPAR) absorbed by the vegetation canopy. Focusing on LUE allows potential drivers of GPP to be separated from its overriding dependence on light. GPP data from over 100 sites, collated over 20 years and located in a range of biomes and climate zones, were extracted from the FLUXNET2015 database and combined with remotely sensed fAPAR data to estimate daily LUE. Daytime air temperature, vapor pressure deficit, diffuse fraction of solar radiation, and soil moisture were shown to be salient predictors of LUE in a generalized linear mixed-effects model. The same model design was fitted to site-based LUE estimates generated by 16 terrestrial ecosystem models. The published models showed wide variation in the shape, the strength, and even the sign of the environmental effects on modeled LUE. These findings highlight important model deficiencies and suggest a need to progress beyond simple "goodness of fit" comparisons of inferred and predicted carbon fluxes toward an approach focused on the functional responses of the underlying dependencies.