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In mammals and birds, tanycytes are known to regulate thyroid hormone conversion, and this process is central to the control of seasonal reproduction. In mammals, this cell type is also implicated in retinoic acid signalling, neurogenesis, and nutritional gatekeeping, all of which have been linked to hypothalamic regulation of energy metabolism. Less is known about these potential wider roles of tanycytes in birds. To address this gap, we combined LASER capture microdissection and transcriptomics to profile the tanycytic region in male Svalbard ptarmigan, a High Arctic species with photoperiod-dependent seasonal rhythms in reproductive activation and body mass. Short photoperiod (SP) adapted birds were transferred to constant light (LL) to trigger breeding and body mass loss. After five months under LL, the development of photorefractoriness led to spontaneous re-emergence of the winter phenotype, marked by the termination of breeding and gain in body mass. The transfer from SP to LL initiated gene expression changes in both thyroid hormone and retinoic acid pathways, as described in seasonal mammals. Furthermore, transcriptomic signatures of cell differentiation and migration were observed. Comparison to data from Siberian hamsters demonstrated that a photoperiod-dependent re-organisation of the hypothalamic tanycytic region is likely a conserved feature. Conversely, the spontaneous development of photorefractoriness showed a surprisingly small number of genes that reverted in expression level, despite reversal of the reproductive and metabolic phenotype. Our data suggest general conservation of tanycyte biology between photoperiodic birds and mammals and raise questions about the mechanistic origins of the photorefractory state. [ABSTRACT FROM AUTHOR]

Higher prevalence of multiple sclerosis at higher latitudes is associated with reduced sunlight during childhood. Alterations in inflammatory Th17 and regulatory T cells (Treg) are associated with autoimmunity. In Hobart, Australia (latitude 42.8° south), thirteen girls (aged 12–13) and sixteen women had blood collected in the evening in daylight in February/March, (post 15 h daylight) and at the same time in the dark in August/September (post 9 h daylight). Height and weight were measured. Participants completed online surveys prior around menstruation, sleep, exercise and time outside. Proportions of Th17 (CD4 + , CXCR3–, CCR4 + , CCR6 + , CD161 +), total Treg (CD4 + , CD25 + , CD127low), naïve Treg (CD45RA + , CD4 + , CD25 + , CD127low) and memory Treg (CD45RA low, CD4 + , CD25 + , CD127low) were enumerated by flow cytometry (Cytek Aurora). Hours spent outside was greater in summer than winter (12.5 v 10.5, p = 0.0003). The %Treg/CD4 + was higher in summer than winter (7.3% vs 7%, p = 0.004) including memory Treg (3.1% vs 2.9%, p = 0.02) for all females (n = 29), and naïve Treg were 13% higher in summer in women (3.2% vs 2.8%, p = 0.0009), whereas %Th17 remained unchanged. In women, a negative correlation between the number of hours spent outside in summer and %Th17 was observed (r = – 0.53, p = 0.035). The %Th17 cells were higher in women than girls (4.9% vs 3.1%, p = 0.001), whereas girls had a higher total %Treg (7.6% vs 6.7%, p = 0.005), consisting of a higher naïve Treg (5.5% vs 3.7%, p = 0.0001) while the women had a higher %memory Treg (3.4% vs 2.6%, p = 0.0001). These light-dependent seasonal differences may influence immune development in adolescents. [ABSTRACT FROM AUTHOR]

Agniyar estuary in Palk Bay on the southeast coast of India, is an important estuary bordering Point Calimere Key Biodiversity Area. Information on the fish diversity and guild dynamics of this typical tropical estuary is lacking. Hence, the present study provided an account of fish diversity and guild dynamics. The study collected 2342 fish specimens from 18 orders, representing 76 species from 32 families. The predominant order and family were Eupercaria and Sciaenidae, respectively. Thryssa mystax (Bloch & Schneider, 1801), T. malabarica (Bloch, 1795), and Setipinna taty (Valenciennes, 1848) were the most dominant species in terms of abundance. The study recorded seasonal variations in temperature, salinity, pH, and dissolved oxygen, with the summer exhibiting the highest temperature and salinity. The Kruskal–Wallis test followed by Dunn's post hoc analysis revealed significant differences in the nutrient concentrations (nitrite, nitrate, and phosphate). The redundancy analysis and Pearson correlation explained the significant relationship between species abundance and environmental conditions. Diversity indices and dominance/diversity patterns during the pre-monsoon were more dominant and diverse, whereas the summer recorded the lowest diversity. Cluster analysis and similarity profile (SIMPROF) revealed a high level of similarity and a lack of distinct differentiation among the seasonal clusters. The analysis of guild dynamics indicated seasonal fluctuations in ecological, feeding, vertical distributional, and reproductive guilds. The seasonal occurrence of the IUCN Red List category of fishes was presented, and their vulnerability to seasonal changes was elucidated. Significant information on the fish community structure, dynamics, and conservation measures was provided to protect the Agniyar estuary. [ABSTRACT FROM AUTHOR]

The tritium content in the surface water of the Suifen River in China was measured using an ultra low-level liquid scintillation spectrometer. In August and October, a total of 30 samples were collected (15 per month) The measured 3H activity concentration ranged from 5.08 to 9.75 Bq L−1, and the annual effective dose ranged from 0.07 to 0.13 μSv. These values are below WHO's recommendations, indicating no risk to human health. Although the 3H activity concentration was higher in October than in August, statistical analysis did not show a significant difference between the two months. [ABSTRACT FROM AUTHOR]

The Onychostoma macrolepis have a unique survival strategy, overwintering in caves and returning to the river for reproduction in summer. The current knowledge on the developmental status of its testes during winter and summer is still undiscovered. We performed RNA-seq analysis on O. macrolepis testes between January and June, using the published genome (NCBI, ASM1243209v1). Through KEGG and GO enrichment analysis, we were able to identify 2111 differentially expressed genes (DEGs) and demonstrate their functions in signaling networks associated with the development of organism. At the genomic level, we found that during the overwintering phase, genes associated with cell proliferation (ccnb1, spag5, hdac7) were downregulated while genes linked to testicular fat metabolism (slc27a2, scd, pltp) were upregulated. This indicates suppression of both mitosis and meiosis, thereby inhibiting energy expenditure through genetic regulation of testicular degeneration. Furthermore, in January, we observed the regulation of autophagy and apoptosis (becn1, casp13), which may have the function of protecting reproductive organs and ensuring their maturity for the breeding season. The results provide a basis for the development of specialized feed formulations to regulate the expression of specific genes, or editing of genes during the fish egg stage, to ensure that the testes of O. macrolepis can mature more efficiently after overwintering, thereby enhancing reproductive performance. [ABSTRACT FROM AUTHOR]

İstanbul is the largest city located in the Mediterranean Basin and has a medium to high risk of climate change and future climate risks. Changes in temperature and other weather variables have had significant impacts on İstanbul. In this context, there is a need for studies on the issues of climate monitoring and climate change vulnerability to reduce the adverse impacts. The aim of this study is to investigate the temperature trends of synoptic weather station in İstanbul Atatürk Airport between 1973 and 2023 to have a general idea about how the temperature has changed over the last half-century and to establish statistically whether a trend is significant or not. The values of minimum (Tmin), maximum (Tmax) and mean (Tmean) temperature related parameters were estimated. Annual, monthly and seasonal temperature trends are also analyzed. The findings of this study indicate a significant (p < 0.001) rise in the mean air temperature (Tmean) of İstanbul over the past 51 years (1973–2023), with an annual warming trend of 0.06 °C. The strongest increasing trend in seasonal mean air temperatures has been observed in the summer season, with an increase of 0.08 °C per year. The trend analysis also shows a statistically non-significant increase in yearly average minimum temperature (Tmin) between 1973 and 2023, with a rate of 0.04 °C per year. However, the annual maximum temperature (Tmax) has shown no changes. [ABSTRACT FROM AUTHOR]

When animals are exposed to higher-than-optimal temperatures, they are expected to thermoregulate by decreasing their activity and seeking cooler areas. However, individuals of certain species continue performing reproductive behaviors instead of thermoregulatory behaviors during challenging conditions. This trade-off has been demonstrated in aquatic animals, but not in terrestrial ectotherms. This research gap is important given the relevance of survival-reproduction trade-offs in evolutionary ecology and the pace of current habitat warming. We explored this potential trade-off in territorial males of the lizard Sceloporus ochoterenae, which mate during the hot-dry season in seasonally dry tropical forest. We first assessed the existence of a temporal trade-off between performing push-ups (territorial behavioral display) versus sheltering in the shade (thermoregulatory behavior), then used confirmatory path analysis to explore how it was affected by tree cover, microclimate temperature, and the presence of a conspecific intruder. We found that territories with less tree cover had higher microclimate temperatures, where focal males spent more time performing push-ups at the expense of sheltering in the shade. Focal males also spent more time performing push-ups the longer an intruder was present, who was also affected by the environmental variables. Territorial males spent more time in sunny spots when performing push-ups despite the potential loss of moisture and energy reserves, perhaps because the display is more effective when performed in the open. The potential effects of continued habitat warming on this trade-off could intensify it or driving lizards to change their daily activity rhythms. Significance: We explored a fundamental life history trade-off: self-maintenance vs. reproduction. Specifically, we evaluated the potential trade-off between sheltering in the shade to cool off and performing dynamic territorial displays in a lizard endemic to seasonally dry tropical forest in Mexico. This trade-off is expected to be especially strong because this species breeds during the hottest, driest, and most food-limited season of the year. We found support for the trade-off, as performing push-ups was negatively related to both shade use and tree cover, and path analysis showed that males sacrifice time in the shade in favor of displaying (not vice-versa). These results are similar to dynamics reported in aquatic animals, but this is to our knowledge the first such report in a terrestrial vertebrate. These findings are especially relevant in the context of habitat warming due to deforestation and climate change. [ABSTRACT FROM AUTHOR]

This study aimed to explore seasonal variations in temporomandibular disorder (TMD) prevalence in South Korea, utilizing nationwide population-based big data. Data corresponding to the Korean Standard Classification of Diseases code of K07.6, which identifies TMD, were extracted from the Health Insurance Review and Assessment Service online platform for the period from 2010 to 2022. Additionally, we integrated these data with climate temperature records from the Korean Meteorological Administration. We subsequently conducted a statistical analysis of TMD patient data on a monthly and seasonal basis over the past 13 years to assess prevalence. Over the past 13 years, the number of TMD patients in Korea has steadily increased. The prevalence of TMD rose from 0.48% (224,708 out of a total population of 50,515,666) in 2010 to 0.94% (482,241 out of a total population of 51,439,038) in 2022, marking a 1.96-fold increase. Among children under 10 years of age, no significant differences were observed in TMD prevalence between boys and girls. However, a distinct female predominance emerged after the age of 10, with an average female-to-male ratio of 1.51:1. The peak prevalence of TMD occurred in individuals in their 20 s, followed by adolescents in their late 10 s. The majority of TMD patients were concentrated in Seoul and Gyeonggi province, with metropolitan areas accounting for 50% of the total patient count. Seasonally, TMD patient numbers showed no significant increase in winter compared with spring or summer. The temperature difference, defined as the absolute difference between the highest and lowest temperatures for each month, showed a positive correlation with TMD patient counts. A greater temperature difference was associated with higher patient counts. The strongest correlation between temperature differences and TMD patient numbers was observed in winter (r = 0.480, p < 0.01), followed by summer (r = 0.443, p < 0.01), and spring (r = 0.366, p < 0.05). Temperature differences demonstrated a significantly stronger correlation with the increase in the number of TMD patients than absolute climate temperatures. This aspect should be a key consideration when examining seasonal trends in TMD prevalence in South Korea. [ABSTRACT FROM AUTHOR]

Diatom assemblages from ARA2B-1A taken in the Chukchi Sea shelf were analyzed to reconstruct paleoenvironmental changes during the last 10 ka BP. The main factors controlling the distribution of diatom in the Chukchi Sea are the relatively warm and nutrient-rich Pacific water inflow after the opening of the Bering Strait. Based on the selected diatoms, three diatom assemblage zones are identified. The diatom assemblage zone I shows a rare or very low abundance, which corresponds to the early Holocene (10–8 ka BP). The diatom assemblage zone II corresponds to the mid-to-late Holocene (8–2 ka BP). It is a seasonal sea-ice environment with relatively abundant diatom valves and Chaetoceors resting spores, as well as sea-ice species, cold-water species, coastal species, and upwelling species. The diatom assemblage zone III corresponds to the late Holocene (2–0 ka BP), and the the sea-ice species generally decreased compared to zone II, while the coastal species Paralia sulcata occurred abundantly. In particular, the Thalassiosira antarctica, a cold-water species, increased distinctly during this time interval. After ∼2 ka BP, T. antarctica rapidly increased while sea-ice species rarely appeared, indicating limited open-marine environments. In particular, after 1 ka BP, T. antarctica decreased while the sea-ice species increased, suggesting that the sea-ice increased again before the recent global warming of the Arctic, the late Holocene. [ABSTRACT FROM AUTHOR]

The multidecade, seasonal, and interannual variability of hydrometeorological parameters of the Black Sea has been analyzed with reference to the population dynamics of invasive ctenophores. Polynomial approximations of average annual time series indicate a nonlinear character of the long-term variability of the studied parameters. Two 20- and 40-year intervals with multidirectional trends of parameter changes have been revealed. The effect of variability of abiotic factors on the two main ecosystem drivers, i.e., invasive ctenophore Mnemiopsis leidyi A. Agassiz, 1865 and its predator Beroe ovata Bruguière, 1789, has been analyzed. M. leidyi invaded the Black Sea in the 1980s, followed by the B. ovata invasion in the 1990s. The M. leidyi invasion caused degradation of the ecosystem at all trophic levels, including fish resources. The subsequent introduction of its predator, B. ovata, provided a significant restoration of the ecosystem and fish resources in the Black Sea; this process still continues in the Sea of Azov. The interannual dynamics of both ctenophores follows water temperature changes, but only if it varies within the limits favorable for these species. In the case of exceeding these limits, a sharp reduction of their population magnitudes occurs. [ABSTRACT FROM AUTHOR]

Evaluation of climate model skills in reproducing local-scale climate conditions is an important aspect of climate studies. This study aimed to assess the performance of five Regional Climate Models (RCMs) available in the Coordinated Regional Climate Downscaling Experiment (CORDEX). The assessment was based on how well the RCMs replicated rainfall, maximum and minimum temperatures, interannual and seasonal variations over southeastern Ethiopia during the simulation period of 1980–2005. The results indicated that the Regional Climate Models (RCMs) exhibited substantial bias in simulating annual rainfall cycles, particularly in higher elevation areas of the study region. The Regional Model (REMO2009) simulated the maximum temperature, while the Regional Atmosphere Climate Model (RACMO22T) better simulated the minimum temperature compared to other models. However, the ensemble of models performed better than the individual RCMs in simulating the annual cycle of temperature. The variation in rainfall was greater than the variation in temperature, both seasonally and interannually. RACMO22T and Climate Limited Area Modeling (CCLM4-8) showed better performance in capturing the cumulative distribution of rainfall events and return period. The Regional Atmospheric Model (RCA) was characterized by a significant overestimation of cumulative distribution and return period. The disparity in performance among the Regional Climate Models indicates their sensitivity to location and topography. Therefore, the selection of a suitable RCM for a specific location is essential for any climate-related and other definite articles study or local climate projections. [ABSTRACT FROM AUTHOR]

Purpose : Obstructive sleep apnoea (OSA) and cardiac conduction disorders are pathologies with a rising prevalence due to increased life expectancy. Upper airway patency is affected by environmental factors that may be associated with seasonal periods. The ability to record the degree of nocturnal apnoea on a daily basis may provide a more accurate picture of seasonal variability. Methods: This study used an observational, cross-sectional design recruiting consecutive patients with Sorin/Livanova/Microport® pacemakers. The study assessed the seasonal influence on the daily degree of nocturnal apnoea over a minimum period of 180 days. The respiratory events were recorded using a pacemaker-integrated detection algorithm based on transthoracic impedance variation. A generalised linear repeated measure mixed model was used to study the seasonal effect. Results: A sample of 101 subjects with a mean of 227 valid nights was compiled. Summer was associated with higher RDI (respiratory disturbance index) values and winter with lower values. The mean daily RDI ratio in summer was 1.099 times higher than in winter. Conclusions: Slight seasonal influences on the degree of nocturnal apnoea were detected through the daily observation of an unselected sample of pacemaker wearers. The degree of apnoea is higher in warmer months and lower in colder months. [ABSTRACT FROM AUTHOR]

Apalachicola Bay, a river-fed estuary in the northeast Gulf of Mexico is experiencing impacts from anthropogenic and climate-induced changes in freshwater inputs and sea level rise. These synergistic pressures have resulted in a historic oyster fishery collapse and the expansion of mangroves, which are displacing native salt marsh. Understanding how these natural and man-made-driven changes have affected the nekton community is essential for the sustainable management of this coastal region. To evaluate changes in nekton occurrence and distribution in Apalachicola Bay, we analyzed 20 years of biological monitoring data. Our results indicated that spatial variation in species' populations was driven by differences in salinity, while seasonal changes were driven by temperature. Freshwater inflow is the primary driver of salinity, and these differences demonstrated that river flow reductions have the potential to alter nekton communities. The effects of climate-driven droughts and anthropogenic freshwater flow reductions on estuarine community structure highlight the importance of maintaining sufficient river flow for nursery areas, which provide ecosystem services for the region. Ultimately, these findings support the continued need for monitoring programs that track accelerating ecosystem change and provide a clearer understanding for how community composition will respond to global change. [ABSTRACT FROM AUTHOR]

Estuaries are among the most dynamic ecosystems in coastal regions and are facing serious threats due to increasing anthropogenic activities. The aim of the present study is to evaluate the water quality of the Rushikulya estuary by analyzing the abundance of pathogenic bacteria in both its water and sediment. Water and sediment samples were collected from five different stations at the mouth of the Rushikulya estuary during the monsoon and post-monsoon seasons. These samples were analyzed to assess the abundance of pathogenic bacteria and environmental parameters. The results revealed that bacterial abundance is significantly higher in the sediment than in the water, possibly due to a longer residence time of pathogenic bacteria in the sediment. Seasonal observations indicated an increase in pathogenic bacterial abundance during the monsoon season, suggesting an impact from monsoonal discharge. Escherichia coli-like organism, faecal coliforms, Shigella-like organisms, and Vibrio cholera-like organisms were the dominant pathogenic bacteria in both the water and sediment of the Rushikulya estuary. The higher abundance of these pathogens and the results of statistical analysis, which showed a strong correlation between Total Streptococci and BOD (r = 0.79), indicate the influence of human settlement and the mixing of untreated sewage in the Rushikulya estuary. The elevated levels of E. coli, faecal coliforms, and Shigella-like organisms in the Rushikulya estuary raise significant concerns that require immediate attention. [ABSTRACT FROM AUTHOR]

The rise of urbanization has led to many critical issues like increased air pollution, emission of more greenhouse gases, sudden climate change, and a rise in temperature of an urban area compared to surrounding rural regions known as urban heat islands (UHI). It becomes crucial to understand the effect of climatic conditions in those areas. In this present research, we have chosen two different cities: Bhopal and Guwahati, situated over different climatic conditions. The study examines the diurnal, seasonal and inter annual variability of surface UHI (SUHI), using MODIS LST (MOD11A2 and MYD11A2) product of 1 km spatial resolution from 2003 to 2018. The temporal trend of LST is estimated using Mann–Kendall and Sen's slope estimator test. This study also evaluates the land use land cover (LULC) change over the two cities using the LULC data. The present research also incorporates the determination of six different driving factors of SUHI starting from built-up area, urban–rural difference in evapotranspiration, black sky albedo, enhanced vegetation index, thermal inertia, and population. Pearson's correlation criteria are used to determine the correlation of SUHI with each of the determinant parameters. The results reveal the presence of a cool urban island during the summer daytime in Bhopal, while Guwahati shows a positive SUHI. The nighttime shows clear evidence and higher SUHI magnitude than the daytime for Bhopal city. Contrary, a reverse phenomenon is evident in Guwahati with higher SUHI magnitude during the daytime compared to nighttime. The negative SUHI variation can be ascribed to rural area dynamics with the majority of cropland cover. The evapotranspiration shows reasonable control of SUHI's daytime variation. Thermal inertia was found to be an influential parameter in explaining the diurnal variation of SUHI. [ABSTRACT FROM AUTHOR]

Skillful prediction of wintertime cold extremes on seasonal time scales is beneficial for multiple sectors. This study demonstrates that North American cold extremes, measured by the frequency of cold days in winter, are predictable several months in advance in the Geophysical Fluid Dynamics Laboratory's SPEAR (Seamless system for Prediction and EArth system Research) seasonal forecast system. Three predictable components of cold extremes over the North American continent are found to be skillfully predicted on seasonal scales. One is a trend-like component, which shows a continent-wide decrease in the frequency of cold extremes and is primarily attributable to external radiative forcing. This trend-like component is predictable at least 9 months ahead. The second predictable component displays a dipole structure over North America, with negative signs in the northwest and positive signs in the southeast. This dipole component is predictable with significant correlation skill for 2 months and is a response to the central Pacific ENSO (El Niño-Southern Oscillation) as revealed from SPEAR AMIP-style simulations. The third component with the largest loadings over Canada and the northern US shows significant correlations with snow anomalies over mid-to-high latitudes of the North American continent. Predictions using only the three predictable components yield higher/comparable skill relative to the SPEAR raw forecasts. [ABSTRACT FROM AUTHOR]

Hunting is a critical source of food security and income for millions of people across the Amazon Basin, but unsustainable hunting is one of the leading causes of biodiversity loss worldwide. Models on the sustainability of hunting often use a spatial estimate of hunting pressure which radiates constantly from a central location. We used participatory mapping and interview techniques with hunters and a generalized linear modeling approach to determine how the spread of hunting pressure varies spatially and through time, and how harvests changed accordingly, in a riverine indigenous community in the Peruvian Amazon. Model results showed significant variation in the spatial spread of hunting pressure seasonally, where the upper regions of the river basin were predicted to be relatively inaccessible during the dry season. Significant covariates included landscape characteristics such as distance from major rivers and presence of major trails and seasonal streams, as well as monthly rainfall and month of the year among others. Catch also varied by month, and spatially reflected the spread of monthly hunting pressure. Catch per unit effort (CPUE) was significantly related to rainfall (estimate = − 0.0036, SE = 0.00061, p < 0.001), and monthly patterns in CPUE matched those of game meat sales. Seasonally changing environmental characteristics like rainfall and water level likely influence the species and zones that hunters have access to and may influence the sustainability of hunting of some species as areas they inhabit become inaccessible during the dry season. [ABSTRACT FROM AUTHOR]

Vitamin D has a well-established role in regulating the intestinal absorption of minerals but its association with immunity has not been extensively explored in livestock. Although an optimal circulating concentration of 30 ng/ml 25-hydroxycholecalciferol (25(OH)D) is proposed for immune function, it is unknown if this vitamin D concentration is sufficient, particularly for cows under a pasture-based, spring-calving dairy production system. The objectives of this retrospective analysis were to assess circulating vitamin D concentrations in a total of 843 bio-banked serum samples from Holstein-Friesian dairy cows enrolled from 12 spring-calving, pasture-based dairy farms in Ireland. Mean 25(OH)D concentrations were 36.3 ng/ml at calving, 30.7 ng/ml at 7 days post-partum (DPP), and 38.3 ng/ml at 21 DPP. However, mean concentrations masked significant inter-farm and inter-individual variation (P < 0.05). In fact, the proportion of cows with vitamin D insufficiency of < 30 ng/ml was found to be 33.8%, 55.5% and 19.5% at each time point, respectively. In addition, 25(OH)D concentrations correlated positively with immune cell populations (monocytes and lymphocytes) and negatively with blood urea and non-esterified fatty acids (NEFA) at 7 DPP. This is the first report of 25(OH)D concentrations in pasture-based peripartum dairy cows and we show a high degree of variation across farms and between individual animals. Sub-optimal concentrations of vitamin D in some post-partum cows may predispose cattle to multiple metabolic or infectious diseases, and therefore further work is now warranted. [ABSTRACT FROM AUTHOR]

The variability of upwelling along the Koryak coast in the northwestern Bering Sea is studied using wind data from the QuikSCAT/SeaWinds (2000–2009) and MetOp-A/ASCAT (2010–2020) scatterometers. The strength of upwelling is estimated based on the wind speed and wind-induced offshore Ekman mass transport (upwelling index). The results indicate that the upwelling that occurred along the Koryak coast was primarily driven by the southerly summer winds over the Bering Sea. The Koryak coastal upwelling occurs mainly during June–August, with significant interannual variability. The variability of the upwelling is primarily driven by regional wind forcing. The seasonal variability of southerly winds favorable for the development of upwelling largely depends on the state of the summer Far Eastern depression (a regional atmospheric center of low pressure). The variations in the pressure field correlate well with the successive alternation of upwelling and downwelling processes near the Koryak coast. Intense upwelling is associated with the well-developed Far Eastern depression. Upwelling can be replaced by downwelling when this regional center of atmospheric action is weakened. [ABSTRACT FROM AUTHOR]

This is the second of three papers dealing with metal-bearing circumneutral mine drainage from the inactive Rico-Argentine mine site located at an elevation of ≈ 2740 m (9000 feet) in the San Juan mountain range in southwestern Colorado. This paper evaluates two years of mine drainage treatment using a passive system that included a vertical-flow engineered biotreatment cell. The collapsed St. Louis Tunnel (SLT) discharges circumneutral mine water from several sources that contains elevated concentrations of Cd, Cu, Fe, Mn, Zn. A demonstration-scale 114 L/min (30 gpm) gravity-flow passive treatment system was installed, consisting of a settling basin (utilizing coagulant addition to improve suspended solids settling efficiency), an anaerobic sulfate-reducing bioreactor, and an aeration cascade for effluent polishing. The treatment system generally met target treatment goals for Cd, Cu, Fe, and Pb. Nanophase ZnS in system effluent decreased the frequency of meeting total Zn project treatment goals. Unexpectedly high levels of Mn removal were observed in both the anaerobic bioreactor and the aeration cascade. Large seasonal variations in influent metals concentrations and pH present the greatest challenge in managing system performance. [ABSTRACT FROM AUTHOR]

Microplastics are a widespread environmental contaminant that raises serious concern for aquatic organisms. Hence, the present study was conducted to investigate the spatial and seasonal variation of microplastics, their characteristics, polymer types and the risk assessment caused by the microplastics in six sampling sites along the Thoothukudi region. The average microplastic abundance ranged from 32 ± 26 to 232 ± 229 items/kg and 54 ± 41 to 619 ± 377 items/l in sediment and surface water, respectively, and they exhibited a significant spatial difference among the sampling sites. The microplastic abundance also showed a significant difference among the seasons with the monsoon significantly recording the highest mean microplastic abundance in sediment (160 ± 130 items/kg) and surface water (454 ± 374 items/l). In sediment and surface water, fragment (sediment: 52.72%, surface water: 40.89%), 0.5–1 mm (sediment: 43.96%, surface water: 31.11%) and blue-coloured (sediment: 52.33%, surface water: 41.85%) microplastics were dominant with no significant difference both spatially and seasonally. Polyethylene, the dominant polymer, was observed in both the sediment and surface water, accounting for about 47.58% and 49.83%, respectively, and it showed no significant difference among the selected sites. This signifies that they are homogenously distributed along the coast and further suggests that these particles persisted in the sediment and surface water for a longer period of time. The results of the polymer hazard index show that the sediment (PHI = 1181.63) and surface water (PHI = 1018.66) were severely contaminated (hazard level V) with microplastic polymers such as PE, PP, PS, PET and PA. It was also found that the degree of the microplastic contamination in sediment (PLI = 3.57) and surface water (PLI = 3.84) was lower (hazard level I). The overall risk index (RI) for sediment (253.48) and surface water (444.74) falls under the higher risk category. From the correlation analysis, a significantly positive relationship was observed between microplastics in sediment and surface water based on each classification (abundance, shape, size, colour and polymer). This suggests that microplastics rejoin the water column from the sediment through resuspension, which occurs due to the circulation, tides and sedimentation rate. This might be the reason for the higher microplastic abundance in the surface water than in the sediment. As a result, proper management measures to reduce plastic waste disposal in the marine environment should be implemented to lessen the effects of microplastics on marine biota and on public health. [ABSTRACT FROM AUTHOR]

Over the last few years, decadal prediction has been paid much attention for its potential applications in agriculture, hydrology and for assessing the climate impact on the various aspects of human life. Though the fidelity of decadal prediction specifically the hindcasts experiments through Coupled Model Inter-comparison Project Phase 5 (CMIP5) has been examined for many climate variables and at different temporal and spatial scales, the drift in CMIP5 decadal precipitation at a local scale remains unknown. Drift is the long-term time varying systematic bias generated by GCMs while they revert to their equilibrium state from the forced initialized state. This study used seven general circulation models (GCMs) from five different modelling groups to examine the drift in monthly and seasonal mean precipitation from the CMIP5 decadal hindcasts for Brisbane river catchment, Australia. Drifts of individual model's ensemble mean and multi-model ensembles' mean (MMEM) at monthly and seasonal time scales were quantified and examined using four different skill tests. Results revealed that the magnitude of drifts are higher in monthly precipitation than the seasonal mean precipitation. Next, the drift in hindcast precipitation was corrected using mean drift correction method and found that the mean drift correction method is not sufficient to alleviate the drift in CMIP5 decadal precipitation. This suggests further research for an appropriate drift correction method for decadal precipitation. Comparing the drift and skill test results over the entire catchment, this study finds, MMEM showing the lowest drifts and outperformed in all models in skill tests. [ABSTRACT FROM AUTHOR]

Seasonally reproducing small mammals often undergo changes in brain anatomy throughout the year. Much of the research on this seasonal neuroplasticity has focused on changes in hippocampus volume and neurogenesis, with relatively little attention paid to neuronal morphology. Here, we test for sex, season and sex–season interaction effects on hippocampal neuron morphology and dendritic spine density in a seasonally reproducing rodent: Richardson's ground squirrel (Urocitellus richardsonii). We quantified the morphology and spine densities of Golgi-stained pyramidal neurons and granule cells in the hippocampus and tested for differences between sexes and seasons with generalized linear models. Although we found no significant sex differences or sex–season interaction effects on any of our morphological measurements, there were significant differences in neuron morphology and spine density between breeding and non-breeding seasons. In the non-breeding season, ground squirrels had CA1 neurons with longer basal dendrites with more branches than in the breeding season. Non-breeding season animals also had higher apical and basal dendrite spine density in CA1 and CA3 neurons than breeding-season animals. Conversely, the spine densities of CA1 somata and granule cells were higher in breeding than in non-breeding season. These differences in neuron morphology and spine density between breeding and non-breeding seasons likely arise from a combination of activity levels, stress hormones, and photoperiod. Although the functional implications of seasonal changes in hippocampal neuron morphology and spine density are uncertain, our data suggest that ground squirrels may be a good model for understanding seasonal neuroplasticity in mammals. [ABSTRACT FROM AUTHOR]

Black carbon (BC) may have more adverse effects on human health than other constituents of PM2.5. The daily mean concentrations of BC in China are much higher than those in developed countries and are estimated to account for more than a quarter of global anthropogenic BC emissions. However, reports on the health effects of BC in China have been limited. Thus, a time-stratified case-crossover study was conducted to evaluate the impacts of BC on daily mortality risk in nine Chinese megacities from 2008–2016. Our results show that for all-cause mortality, when compared to the interquartile range (IQR) of BC concentration increased, odds ratios (ORs) were in the range of 1.01–1.06 (95% CIs: 0.99–1.10). For cardiovascular mortality, ORs were in the range of 1.02–1.07 (95% CIs: 1.003–1.12), and for respiratory mortality, ORs were in the range of 1.01–1.15 (95% CIs: 1.00–1.18). The effects of BC in the nine cities were robust after adjusting for PM2.5, or even became more prominent. Furthermore, BC had stronger effects in spring and winter in northern cities, whereas in mid-latitude cities, BC had stronger effects in the warm seasons. In southern cities, BC had stronger effects in the cool and dry seasons. Our findings support an association between residential exposure to BC and mortality and thus provide further evidence that BC negatively impacts human health and is helpful for decision-making. [ABSTRACT FROM AUTHOR]

Differences in PCDD/Fs concentrations were registered among adult bank voles (Myodes glareolus) inhabiting forest in the vicinity of the Landfill Salariyevo (Moscow, Russia) and caught in early spring (over-winter survivors) and late summer. The levels of highly toxic congeners and WHO-TEQ05 in samples of wintering voles were much lower than those in samples got in summer. This difference was investigated analyzing PCDD/Fs in sexually matured animals and offspring obtained in vivarium. Practically, no significant differences of PCDD/Fs concentrations and general toxicity were revealed among sexes. The main impact to these seasonal differences in PCDD/Fs accumulation was assigned to the types of functional development and activity, diet variation as natural growth of all voles occurs on the same territory but in seasonally diverse conditions. So, the species functional ecology (lifestyle and seasonal features) should be considered in practical application of animal models from natural populations for local monitoring of PCDD/Fs body burden, and individual functional type of ontogenesis among cyclomorphic mammalian species, especially. Thus, the results obtained during monitoring should be carefully interpreted for a proper environmental management. [ABSTRACT FROM AUTHOR]

Lake George is a highly monitored, oligotrophic lake that experiences widespread tourism in the summer months. The southern basin has more shoreline development than the northern basin, resulting in a south to north gradient of anthropogenic impairment. This study aimed to assess differences in nearshore diatom communities regarding gradients of water chemistry and watershed development throughout the lake. Using redundancy analyses, water chemistry explained more variation within diatom assemblages than watershed variables. Seasonal comparisons of watershed types, based on development, revealed SPC values to be significantly higher in the southern basin in all three seasons (spring, summer, and autumn). Among the three seasons, summer demonstrated the best potential for further monitoring of diatom communities with the north and south basins demonstrating differences in Shannon–Weiner (H′) diversity index values and proportions of Asterionella formosa, Fragilaria crotonensis, and Lindavia lemanensis. Dominant diatoms from previous studies in the lake were compared to present populations and showed a concomitant reduction in Stephanodicus spp. and Melosira spp. while smaller centric species continue to increase. Given the differences between the two basins, climate change is likely to manifest differently in the southern, more productive basin than the northern basin. [ABSTRACT FROM AUTHOR]

Soil respiration is one of the main fluxes in the global carbon cycle and has high temporal and spatial variability. Respiration of a soddy-weakly-podzolic soil (Entic Podzol Arenic) in forest and meadow coenoses of the south-taiga zone was continuously monitored on a year-round basis for 21 years; the collected data allows us to assess the temporal variability of CO2 fluxes from soils at different temporal levels: monthly, seasonal, and annual. The total respiration of the soddy-weakly-podzolic soil varies most significantly at the monthly averaging level (coefficient of variation, CV = 25–56%); while the annual respiration variability is 20–22%. At the seasonal averaging level, winter CO2 fluxes from soils have the highest variability (CV = 39–44%); in contrast, during other calendar seasons, soil respiration variability remains roughly at the same level: 26–29%. The effect of the coenosis type on total CO2 fluxes from the soddy-weakly-podzolic soil is statistically significant both at the annual averaging level and in all calendar seasons of the year, except for winter. The most stable parameter that characterizes the seasonal distribution of CO2 fluxes throughout the year is the contribution of the warm period (May–October) to the total annual CO2 flux from soils (73–77% on average). In both studied coenoses, its variability over the 21-year observation period was 8%. This parameter can be used to estimate annual CO2 fluxes from soils based on field measurements performed during the growing season. Results of numerical experiments show that continuous measurements of CO2 emissions from soils for 5 consecutive years reduce the variability of annual and seasonal CO2 fluxes from soils by more than half compared with 1‑ or 2-year measurement periods. Accordingly, a 5-year observation period can be recommended as the optimal one: its duration is sufficient to obtain adequate values of annual and seasonal CO2 fluxes from soils in the south-taiga zone. [ABSTRACT FROM AUTHOR]

The aim of this research was the analysis of the effect of a dam height raise on the water quality of a tropical reservoir used for drinking water purposes in South East Asia. Analyses of iron, manganese, pH and ammonia were performed over a 5-year period from daily water sampling at the reservoir. In addition, high-frequency monitoring data of nitrate, ammonium, pH and blue-green algae were obtained using a monitoring probe. The results showed that due to the raising of the reservoir water level, previously oxic sediments became submerged, triggering an increase in iron and manganese in particular due to the establishment of reducing conditions. Manganese concentrations with values up to 4 mg L−1 are now exceeding guideline values. The analysis strongly indicated that both iron and manganese have a seasonal component with higher iron and manganese concentrations during the wet season. Over a three-year period afterwards, concentrations did not go back to pre-raise levels. The change in water quality was accompanied by a change in pH from previous values of around 5 to pH values of around 6.5. Geochemical simulations confirmed the theory that the increasing concentrations of iron and manganese are due to the dissolution of MnO2 and ferric oxyhydroxides oxidising organic matter in the process. This study showed that changes in reservoir water levels with the establishment of reducing conditions can have long-term effects on the water quality of a reservoir. [ABSTRACT FROM AUTHOR]

Reliable information on the frequency and duration of excessive precipitation in floods, droughts, earthquakes, coastal floods, and hill torrents is critical to natural disaster planning and disaster risk reduction strategies. The current study examined precipitation on a monthly, seasonal, and annual scale at varying amplitudes. Moreover, the Mann–Kendall and Sen Innovatiove trend analysis (ITA) approaches are used to examine precipitation variations. This study aims to evaluate the Mann–Kendall and Sen Innovative Trend Analysis techniques to understand better how they apply to the topic under consideration. Overall, 84.16% of testing months showed trendless precipitation based on the MK trend test. Comparatively, the ITA monthly analysis showed statistically significant variation in 80% months and 88% considerable rate in seasonal perspective over the entire study regions. The research recognized that the Sen Innovative trend test outperforms the Mann–Kendall analysis in a range of circumstances. First of all, Sen Approach has simple assumptions, and the study of skewed distributions with fewer data could apply. Another benefit of using the ITA was that all data sets could be viewed on a graph, making it easier to see patterns and interpret the trends. Thus, the research recommends that the Sen Trend Method (ITA) analyze monthly, seasonal, and annual precipitation patterns to facilitate water resource scheduling and establish natural disaster strategies in the future. [ABSTRACT FROM AUTHOR]

The present study aims to appraise the spatial and temporal dynamics of the coastal waters of the Mumbai coast in India. Four sampling stations were monitored based on the pollution and anthropogenic stress in the coastal area where two stations were fixed near to the coast (off Aksa and Juhu beach), while the other two were away from the coast. Sampling periodicity was monthly for the ten water quality parameters such as SST, pH, salinity, dissolved oxygen levels, alkalinity, chlorophyll a patterns, and nutrient levels such as ammonia, nitrite, nitrate, and phosphate. Overall SST, pH, alkalinity, and phosphorus showed significant variation when the data across seasons were analysed, whereas chlorophyll a and phosphorus showed significant variation across stations in the two-way univariate ANOVA model. SST and pH, and DO and pCO2 had a substantial negative correlation, but SST and salinity, SST and pCO2, pH and DO, alkalinity and pCO2, nitrate and phosphate, and phosphate and pCO2 had a significant positive correlation. Resource-rich coastal areas are continuously threatened globally due to developmental pressure that inevitably affects the environment, especially around megacities. [ABSTRACT FROM AUTHOR]

Background: The paroxysmal nature of migraine is a hallmark of the disease. Some patients report increased attack frequency at certain seasons or towards the end of the week, while others experience diurnal variations of migraine attack onset. This systematic review investigates the chronobiology of migraine and its relation to the periodicity of attacks in existing literature to further understand the oscillating nature of migraine. Main body: PubMed and Embase were systematically searched and screened for eligible articles with outcome measures relating to a circadian, weekly or seasonal distribution of migraine attacks. We found that the majority of studies reported morning hours (6 am–12 pm) as the peak time of onset for migraine attacks. More studies reported Saturday as weekly peak day of attack. There was no clear seasonal variation of migraine due to methodological differences (primarily related to location), however four out of five studies conducted in Norway reported the same yearly peak time indicating a possible seasonal periodicity phenomenon of migraine. Conclusions: The findings of the current review suggest a possible role of chronobiologic rhythms to the periodicity of migraine attacks. Future studies are, however, still needed to provide more knowledge of the oscillating nature of migraine. [ABSTRACT FROM AUTHOR]

We combined a high-resolution acoustic telemetry array with presence/absence receivers to conduct a preliminary study of the seasonal movements, activity patterns, and habitat associations of the newly described Deacon Rockfish (Sebastes diaconus). Eleven mature female Deacon Rockfish were tagged and monitored during an 11-month period, at a nearshore rocky reef off Seal Rock, Oregon, USA, an area of recurring seasonal hypoxia (defined as dissolved oxygen concentration [DO] < 2 mg l−1). Two tags were detected leaving the study area by day 35, indicating predation or emigration. Three tags became inactive within the array, indicating tag loss or fish death. Six "resident" fish inhabited the array for 246–326 days. Resident fish exhibited high site fidelity, small home ranges (mean 95% KDE = 4907 m2), and consistent activity patterns for the duration of the summertime high-resolution array (5 months), except during seasonal hypoxia. Resident fish were strongly diurnal in summer, with high levels of daytime activity above the bottom in relatively rugose habitat, followed by nighttime rest periods in deeper, less rugose habitat. During summertime hypoxia, resident fish exhibited less daytime activity during daytime hours with no rest periods at night, inhabited shallower water depths, and moved well away from their core activity areas on long, erratic forays. During the winter, diel patterns were less evident with higher activity levels at night (than in the summer) and lower activity levels in the day (than in the summer). We propose that some Deacon Rockfish continuously inhabit nearshore reefs throughout the year, but that daily/seasonal movement patterns, seasonally occurring hypoxia, and prey preferences for planktonic organisms influence relocation. [ABSTRACT FROM AUTHOR]

In coastal ecosystems, seaweeds provide habitat and a food source for a variety of species including herbivores of commercial importance. In these systems seaweeds are the ultimate source of energy with any changes in the seaweeds invariably affecting species of higher trophic levels. Seaweeds are rich sources of nutritionally important compounds such as polyunsaturated fatty acids (PUFA) and are particularly rich in long-chain (≥ C20) PUFA (LC-PUFA). In southern Australia, the 'Great Southern Reef' has one of the most diverse assemblages of seaweeds in the world, which support highly productive fisheries and have been recognised as a promising resource of omega-3 LC-PUFA. Despite this, there is little information on the biochemical composition of most species and how it varies between sites and seasons. To address this knowledge gap, we undertook a survey to assess seasonal variability in the biochemical composition (fatty acids and nitrogen content) of abundant understory seaweeds across three sites in eastern Tasmania. The availability of nutritional compounds differed between sites and was primarily driven by differences in the biomass and the biochemical composition of the nutritious red seaweeds at each site. This variability may explain regional differences in the productivity of commercial fisheries. At the species level, seasonal changes in fatty acid composition were highly variable between species and sites, indicating that multiple environmental drivers influence fatty acid composition of seaweeds in this system. This finding suggests that commercial harvest of seaweeds from eastern Tasmania will need to consider species and site-specific variability in fatty acid composition. [ABSTRACT FROM AUTHOR]

Ichthyoplankton communities from Saint John Harbour and Passamaquoddy Bay on the New Brunswick shore of the Bay of Fundy, Canada, were sampled seasonally between 2011 and 2014. Saint John Harbour is an industrialised port whereas Passamaquoddy Bay is less developed, with a focus on aquaculture. In total, 32 species of fish eggs and larvae were recorded: 26 species in Saint John Harbour and 25 in Passamaquoddy Bay. Nineteen species were common to both areas. The dominant species in Passamaquoddy Bay were Enchelyopus cimbrius, Urophycis sp., Scophthalmus aquosus, and Tautogolabrus adspersus. In Saint John Harbour, E. cimbrius, Urophycis sp., Clupea harengus, and Pseudopleuronectes americanus were most abundant. The communities of the two areas were significantly different. This was most pronounced in summer when Saint John Harbour had a much higher proportion of C. harengus and much lower overall abundances, relative to Passamaquoddy Bay. Saint John Harbour demonstrated higher taxonomic diversity than Passamaquoddy Bay, attributable to the wider variety of salinity regimes present within the harbour. In both areas, the ichthyoplankton communities were strongly seasonal with the highest abundance and diversity in summer. Surface temperature was the best predictor of community composition. Given its industrialisation, Saint John Harbour had a surprisingly diverse ichthyoplankton community, comparable to the less impacted Passamaquoddy Bay. The strong flushing in the harbour by high riverine output and tidal exchange may diminish industrial impact. We strongly recommend incorporating ichthyoplankton into the long-term monitoring of Saint John Harbour and provide guidance to this end. [ABSTRACT FROM AUTHOR]

We review the literature on the relationship between water temperature and size of freshwater phytoplankton, to examine the hypothesis that freshwater phytoplankton, like marine phytoplankton and many other groups of organisms, conform to Bergmann's Rule and become smaller with warming. We provide both experimental and field evidence in support of the above hypothesis, much of this evidence was hidden in studies focused on other issues, but presenting temperature and phytoplankton size data. Freshwater phytoplankton size shrinks with increasing temperature at both the species level (by cells or colonies becoming smaller) and at the community level (shift to smaller species). Exceptions to the Rule do occur but in most cases those exceptions can be explained by indirect effects of temperature on phytoplankton size, via processes such as grazing or nutrient availability. With global warming, freshwater phytoplankton are likely to be of smaller size. This article is dedicated to Colin S. Reynolds, who has had a leading role in our personal education and understanding of phytoplankton ecology. [ABSTRACT FROM AUTHOR]

Odor concentrations (OC) and emissions (OE) were measured for a commercial broiler barn and a cage-layer barn in a cold region (the Canadian Prairies). Seasonal OC and OE profiles were plotted by monthly measurements over the course of a year from March 2015 to February 2016, and diurnal profiles were generated by 2-day measurements in cold, mild, and warm seasons, respectively. Seasonal OC and OE varied for both barns; OC was higher in the cold season, but OE was higher in the mild and warm seasons. The broiler barn had higher annual average OC (718 OU m−3) but slightly lower annual average OE (127 OU s−1 AU−1; AU is per 500 kg of body mass) than the layer barn (574 OU m−3 and 140 OU s−1 AU−1). For the layer barn, OC and OE were reduced by 31% and 33% in the cold season and by 30% and 26% in the mild season after manure removal compared with before manure removal. Statistical results showed increased outdoor temperature and ventilation rate (VR) were associated with decreased OC but increased OE for both barns. Finally, both single linear and multi-linear regression models of OE were developed. [ABSTRACT FROM AUTHOR]

Spatial learning is an important cognitive function found across a multitude of species. Natural selection can enhance specific cognitive abilities depending on species ecology but, under certain conditions, spatial learning is also known to vary between sexes according to reproductive status. Despite abundant studies on spatial learning across animal taxa, those focusing on sexually dimorphic spatial learning have been largely limited to rodents. Here, we found that spatial cognition varies between the sexes in an intertidal goby, and this difference fluctuates across seasons. Males and females demonstrated similar cognitive abilities when solving a simple maze during all seasons except spring, when males were significantly less successful than females. Spring marks the beginning of the breeding season for this species, when females move between nests to choose a suitable mate, while males guard their nest and forego foraging excursions. We suggest that the reduction in male cognitive ability reduces metabolic costs at a time of reduced need. This study presents the first evidence for sexually dimorphic spatial learning in fish driven by differences in reproductive behaviour as dictated by the mating system. [ABSTRACT FROM AUTHOR]

Summary: We measured serum parathyroid hormone in 8409 Romanian subjects and found a mild seasonal variation with highest levels in March and lowest levels in September. PTH was dependent on serum vitamin D, particularly below 12.82 ng/mL. Together, these suggest that vitamin D supplementation is warranted only in at-risk groups. Purpose: Seasonal variation of parathyroid hormone (PTH) and its dependency on serum 25-hydroxy vitamin D (25(OH)D) levels are well-described. However, there are few studies from Europe, and genetic, nutritional, and cultural differences are important. We describe the seasonal variation of serum PTH and its relation with serum 25(OH)D levels in Romania. Methods: We retrieved from our endocrinology center database all PTH measurements between 2011 and 2019 together with age, sex, diagnosis, and date of blood sampling. Simultaneous serum 25(OH)D levels were partially available. Intact PTH was measured using the same electrochemiluminescence assay. Results: There were 8409 subjects (median age 49 (36, 60) years; 20.5% men) without a diagnosis of hyperparathyroidism (primary or secondary to chronic kidney disease), hypoparathyroidism, or low bone mass. Serum PTH showed a mild seasonal variation with highest levels at the end of March (47.61 pg/mL) and lowest levels at the end of September (43.15 pg/mL). All sex and age subgroups showed highest levels in the spring and lowest levels in the fall. Males had significantly lower PTH levels than females irrespective of season. PTH correlated inversely with serum 25(OH)D with a breakpoint of 12.82 ng/mL in 2800 subjects who had a simultaneous measurement of 25(OH)D. Increasing age was associated with increasing PTH levels independently of serum 25(OH)D. Conclusions: We showed a mild seasonal variation of serum PTH in Romania, at an inverse sinusoidal pattern than serum 25(OH)D. The breakpoint on the PTH–25(OH)D correlation suggests that vitamin D supplementation is warranted only in at-risk groups. [ABSTRACT FROM AUTHOR]

Changes in temperature and precipitation can have direct effects on a country's economic and sustainable development. This study presents the historical trends in daily extreme temperature and precipitation indices for Barbados, a Caribbean island, for the period 1969–2017. Linear trends were determined on monthly, seasonal, and annual indices derived from daily rainfall, and daily maximum and minimum temperatures collected at Husbands using the Mann-Kendall trend test and the Sen slope estimator. Annual precipitation total, the simple daily rainfall intensity index (SDII), and the total precipitation when daily rainfall was greater than the 95th percentile (R95P) changed significantly by 3.9% per decade, 0.38 mm day−1 per decade, and 2.9% per decade, respectively. Annual trends in mean maximum (TXmean) and mean minimum temperatures (TNmean), 0.06 °C decade−1 and 0.34 °C decade−1, respectively, mask stronger monthly warming trends: TXmean for September and October both warmed at a rate of approximately 0.17 °C decade−1 while TNmean for April warmed at 0.40 °C decade−1. In addition, warming manifests in the frequency of warm nights and cool days at rates of 4.23% per decade and − 2.34% per decade, respectively. Of the extreme temperature indices, the percentage of warm nights (TN90P), cool nights (TN10P), the maximum of the daily minimum temperature (TNX), and the minimum of the daily minimum temperature (TNn) show trends in their monthly indices. These trends indicate warming at Husbands, Barbados, to a greater degree in increasing nighttime temperatures than daytime temperatures. [ABSTRACT FROM AUTHOR]

Shanghai experienced the longest rainy days in 2018/2019 winter since 1988. The physical cause of such an unusual climate condition was investigated through the diagnosis of observational data. From a seasonal perspective, a long persistent rainy winter was often associated with an El Niño condition in the equatorial Pacific. This abnormal oceanic condition induces a remote teleconnection pattern with pronounced low-level southerly anomalies over East China. The wind anomalies transported moisture from tropical oceans and caused persistent rainfall in East Asia. Meanwhile, the local rainfall time series exhibited a strong quasi-biweekly oscillation (QBWO). Three persistent rainy events were identified in the 2018/2019 winter and they all occurred during the active phase of the QBWO. The first two events were associated with a low pressure anomaly west of Shanghai. Southerly anomalies associated with the low pressure system advected high mean moisture into central eastern China, leading to the persistent rainfall there. The third event was associated with a high pressure anomaly in lower troposphere to the east of Shanghai, which induced anomalous southerlies to its west, favoring the occurrence of rainfall in Shanghai. The result suggests the importance of high-frequency variability in affecting seasonal rainfall anomalies. [ABSTRACT FROM AUTHOR]

Circumpolar lakes comprise ~ 1.4 million km2 of arctic and subarctic landscapes and are vulnerable to change in vegetation, permafrost distribution, and hydrological conditions in response to climate warming. However, the composition and cycling of dissolved organic matter (DOM) is poorly understood for these lakes because most are remote and unstudied. The goal of this study was to assess timescale and source controls on DOM composition in Canvasback Lake, a shallow, sub-Arctic lake in interior Alaska with similar hydrologic and geomorphic characteristics to about a quarter of circumpolar lake ecosystems. Lake dissolved organic carbon (DOC) concentration varied by as much as 16% from the mean (3.34 mg L−1 change) through diel cycles in spring 2016 to fall 2017 and was accompanied by minor changes in DOM composition. At the seasonal scale, DOC concentration increased from spring through fall to very high concentrations under ice in winter. Decreases in both condensed aromatic and polyphenolic compound classes and lignin carbon-normalized yield, plus increased relative abundance of aliphatic compounds, suggests that DOM composition shifts from a pulse of allochthonous DOM in the spring to more autochthonous under-ice. These changes highlight the seasonally-dynamic nature of DOM in circumpolar lakes that are poorly captured by single-visit lake surveys and underscores the need to measure DOM properties and fate consistently across multiple timescales (i.e. seasonally) to better constrain the role of DOM in lake processes. To further assess DOM sources, a suite of endmember leachates were compared to bulk lake DOM, indicating solely allochthonous inputs are not well reflected in lake DOM, highlighting the role of degradation processes or mixing with autochthonous sources. Thus, Canvasback Lake appears less well connected to terrestrial inputs compared to past studies of northern high-latitude lakes and does not behave as previous boreal lake models suggest. [ABSTRACT FROM AUTHOR]

Background: The incidence of acute vascular insufficiency of intestine (AVII) is on the rise in the USA and is associated with significant morbidity and mortality. Seasonal variations have been observed in the onset of several gastrointestinal diseases. It is thus far unknown whether the incidence, in-hospital mortality rates, and length of hospital stay (LOS) of AVII vary in different seasons. Aims: The aims of this study were to study the seasonal variations in the (1) incidence, (2) in-hospital mortality, and (3) LOS of AVII in the USA. Methods: We used the Nationwide Inpatient Sample to identify patients aged ≥ 18 years hospitalized from the years 2000–2014. We used the Edwards recognition with estimation of cyclic trend method to study the seasonal variation of AVII hospitalizations and z test to compare the seasonal incidences (peak-to-low ratio), mortalities, and LOS. Results: A total of 1,441,447 patients were hospitalized with AVII (0.3% of all hospitalizations). Patients with AVII were older (69.0 ± 0.1 vs 56.9 ± 0.1) and more commonly females (65.4% vs 35.5%) than patients without AVII (p < 0.001). The incidence of AVII increased through the summer to peak in September (peak/low ratio 1.028, 95% CI 1.024–1.033, p < 0.001). Patients with AVII hospitalized in winter had the highest mortality (17.3%, p < 0.001) and LOS (9.2 ± 0.7 days, p < 0.001). Conclusions: The incidence of AVII in the USA peaks in late summer. The in-hospital mortality rates and LOS associated with AVII are the highest in winter. Physicians could be cognizant of the seasonal variations in the incidence, in-hospital mortality, and LOS of AVII. [ABSTRACT FROM AUTHOR]

The paper presents the results of the analysis of current changes in the annual, seasonal, and monthly inflow of river water to Lake Baikal. A statistically significant increase in the inflow from November to March due to climate change is revealed. The dependence of the annual water level rise in the lake on the inflow is investigated. The pollution of the lake is assessed using the hydrochemical and hydrobiological parameters for the areas being under the influence of the most intensive anthropogenic impact. The background pollution in the reserves on the northeastern coast of the lake is also considered. [ABSTRACT FROM AUTHOR]

Muga silkworm is endemic to North-East India. The quality of primary host plant, i.e. Som. (Persea bombycina Kost.), greatly affects the quality of cocoon and silk production. Som is susceptible to different foliar diseases caused by fungi, which can reduce the yield of leaf from 13.8 to 41.6% annually. So, a comprehensive mycofloral study of the host plant is important to forecast future diseases and design different disease management procedures. This study has been done for a period of 2 years from 2014 to 2016 in Goalpara district of Assam, India. Mycoflora of pedosphere (rhizosphere and non-rhizosphere), phyllosphere and aerosphere were identified and correlated with the seasonal variation. The rhizosphere, air and phylloplane were dominated by Rhizopus stolonifer (22.13%; 15.08%; 24.01%), while Aspergillus niger (12.63%) dominated non-rhizospheric soil. In summer, soil was majorly dominated by A. niger, Aspergillus fumigatus and Curvularia lunata, while R. stolonifer, Aspergillus clavatus and Penicillium chrysogenum dominated the winter soil. Pestalotiopsis disseminata is one of the major pathogens of Som and was found highest in aerosphere followed by phyllosphere. Temperature between 25 and 28 °C with 70–80% of relative humidity favours P. disseminata. This study provides a deep insight into the fungal diversity of Som with respect to pedosphere, aerosphere and phyllosphere, and this knowledge can be used to better select the plantation area and design different disease management strategies to sustain and proliferate the industry for socioeconomic development and to conserve its cultural essence. [ABSTRACT FROM AUTHOR]

Summary: Purpose: The clinical presentation, complications and mortality in molecularly confirmed influenza A and B infections were analyzed. Methods: This retrospective observational single-centre study included all influenza positive patients older than 18 years who were hospitalized and treated at the flu isolation ward during 2017/2018. The diagnosis was based on point-of-care tests with the AlereTM. Results: Of the 396 patients tested positive for influenza, 24.2% had influenza A and 75.8% influenza B. Influenza A patients were younger (median age 67.5 years vs. 77 years, p < 0.001), were more often smokers (27.7% vs. 16.8%, p = 0.021), had chronic pulmonary diseases more frequently (39.6% vs. 26.3%, p = 0.013), presented with a higher body temperature (38.6 °C vs. 38.3 °C, p = 0.004), leucocyte count (8 G/L vs. 6.8 G/L, p = 0.002), C‑reactive protein (CRP) level (41 mg/l vs. 23 mg/l, p < 0.001) and had dyspnea more often (41.7% vs. 28%, p = 0.012). Influenza B patients had an underlying chronic kidney disease in 37% vs. 18.8% (p < 0.001) and presented with vomiting on admission more frequently (21.7% vs. 11.5%, p = 0.027). Influenza A patients were admitted for 8 days vs. 7 days (p = 0.023). There were no differences in the rate of complications; however, 22 (5.6%) patients died during the hospital stay. The in-hospital mortality was higher in influenza A patients (8.3% vs 4.7%, p = 0.172). Conclusion: Some differences were found between influenza A and B virus infections but symptoms were overlapping, which necessitates polymerase chain reaction point-of-care testing for accurate diagnosis. Influenza A was a more severe disease than influenza B during the period 2017/2018. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the influence of season, rainfall and air temperature on the reproductive efficiency in the Romanov breed of sheep in continental part of Croatia during five consecutive years (2012–2016). During this period, 5379 matings resulted in 5046 successful conceptions, i.e. lambings at eight medium-scale Romanov breed sheep farms. The conception rate was 93.81%, fecundity was 195% and average preweaning mortality until 90 days of age was 12.41%. The seasonal distribution of lambings was 47.64% for ewes that delivered in winter (n = 2422), 23.37% in spring (n = 1179), 18.82% in summer (n = 950) and 9.81% in autumn (n = 495). Sexual activity was lowest during spring and early summer when air temperatures were above average (very and extremely warm), and sexual activity peaked from August to September, especially during extremely wet and very wet seasons. Litter size was greater during winter than in other seasons (1.70 vs. 1.54) and was significantly different as compared to each of selected years of the study period. There was a statistically significant difference in the number of pregnant ewes between mating seasons. Most female Romanov lambs born during winter and early spring mated in late summer or autumn and delivered at the age of 1 year or earlier. The seasonal distribution of matings and lambing was not uniform throughout the seasons over five consecutive years. Thus, it can be assumed that air temperature and rainfall during different seasons could affect the reproductive efficiency in Romanov breed of sheep in continental part of Croatia. [ABSTRACT FROM AUTHOR]

Introduction: Influenza may cause severe complications in patients with autoimmune inflammatory rheumatic disease (AIRD), to whom vaccinations are especially recommended. However, AIRD patients require cautious scrutiny of immunogenicity as they might exhibit poor antibody response to vaccination, especially when taking immunomodulatory medications. Aim: The aim was to determine immunogenicity of seasonal and pandemic influenza vaccine in AIRD patients, its timeline/persistence, and influence of medications on immune response. Methods: One hundred and thirty-seven AIRD and 54 healthy controls were vaccinated with trivalent seasonal influenza. After 3–5 weeks, 15 healthy controls and 93 AIRD were vaccinated with pandemic influenza vaccine, and 63 of patients were vaccinated a second time after 3–5 weeks. Sera were collected before vaccination, 18–90 days after each vaccination, and more than 180 days after the last vaccination. The immune response was measured using hemagglutination inhibition (HI) assay and IgG/IgA antibodies against influenza A/B with ELISA. Results: Our findings indicate that following vaccination with seasonal influenza vaccine, seroprotection, seroresponse, and change in geometric mean titers (GMT) in AIRD patients was not compromised compared to healthy. Similarly, we report for pandemic influenza vaccination little added benefit of the second dose. We confirm lowest increase in HI titer in rituximab-treated AIRD compared to other medications. Vaccination largely tilts the balance from negative ELISA A IgG and IgA titers to positive titers in seasonal H1N1 seroresponsive AIRD patients and controls. A significant decrease in HI GMT and seroprotection was observed only in AIRD at > 180 days after vaccination highlighting an absent persistence of immunogenic response in AIRD patients. Due to high initial HI titers for influenza vaccine, we foresee their benefit in personalized medicine in the future. Conclusion: Influenza vaccination is immunologically active for AIRD, with little value of the second dose of the pandemic vaccine and further scrutiny on persistence of immune response to vaccine in AIRD is needed. [ABSTRACT FROM AUTHOR]

Seasonal changes in membrane composition and metabolic activity allow many temperate ectotherms to contend with changes in body temperature, but few studies have investigated whether the plasticity of these traits has diverged within a single species. Therefore, we studied the effects of thermal acclimation on the membrane fatty acid composition and the activities of cytochrome c oxidase (CCO) and citrate synthase (CS) in the skeletal muscle and liver of eastern newts from Maine and Florida. Newts were acclimated to either 6 °C or 28 °C for 12 weeks prior to experiments. Cold acclimation resulted in a lower saturated fatty acid (SFA) content in the muscle membranes of both populations. SFA content in liver was lower in cold compared to warm-acclimated newts from Florida, but acclimation did not affect SFA content in liver membranes of the Maine population. In liver, cold acclimation resulted in a higher monounsaturated fatty acid (MUFA) content in the Florida population and a higher polyunsaturated fatty acid (PUFA) content in the Maine population. Regardless of acclimation conditions, the muscle and liver membranes of the Maine population had higher SFA and PUFA contents compared to those of the Florida population. MUFA content of muscle and liver membranes was higher in the Florida population compared to the Maine population. The effect of acclimation on CCO and CS activity was tissue-specific. In muscle, CCO and CS activities were higher in cold compared to warm-acclimated newts in both populations, and CS and CCO activities were higher in the Maine compared to the Florida population. In liver, CCO and CS activity were unaffected by acclimation in the Florida population, but activity was lower in cold compared to warm-acclimated Maine newts. These results demonstrate that the phenotypic plasticity of these traits in response to seasonal change has diverged between northern and southern populations. [ABSTRACT FROM AUTHOR]

A well-known strategy for minimizing the negative effects of prolonged low temperatures on frost-susceptible subgrade is using insulation layers. Insulation layers help to mitigate the formation of ice lenses and frost heave in the subgrade. This paper evaluates the effect of using bottom ash (B.Ash), as well as polystyrene boards, on the seasonal response of the pavement at the University of Alberta's Integrated Road Research Facility (IRRF) in Edmonton, Canada. Over the course of one year of data monitoring, from July 2014 until July 2015, different seasons (non-freeze-thaw, frozen, and recovering) were distinguished using the temperature and moisture data received from time domain reflectometers (TDRs) and thermistors installed across the pavement depth. Then, the time history data collected from falling-weight deflectometer (FWD) tests was used to identify the characteristic response of different sections. Results revealed that the B.Ash section performed similarly to the control section (CS) in terms of viscoelastic behavior, and the B.Ash perfor med considerably better than the CS in terms of the risk of fatigue cracking. However, the polystyrene sections were more prone to damages during the summer when the hot mix asphalt (HMA) temperature was more than 25°C. [ABSTRACT FROM AUTHOR]

Moisture content management is key to improve forest harvest residue economics for biofuel production. Branches are a large component of these residues, especially when residual bole components are diverted to pulpwood. The literature is not clear about seasonal moisture patterns for the main forest species commercially harvested in Oregon, and most studies have focused on bole wood. A repeated-measurements experiment was implemented to determine seasonal moisture content changes in four western and central Oregon research sites. From all sites, the highest moisture recorded was 50% in ponderosa pine during winter; the lowest was 43% in the summer for Willamette Valley Douglas-fir. Ponderosa pine had significantly higher moisture content in the winter compared to other seasons (1.6-9.0% higher), and summer branch moisture was considerably lower than fall (4.4-2.0% lower). Willamette Valley Douglas-fir branches had significantly lower moisture content during summer compared to other seasons (1.0-4.8% lower). In addition, regression equations were developed to predict branch moisture content from branch height (R² 0.36-0.58) and branch heartwood diameter (R² 0.69-0.93). Although branch heartwood resulted in a more accurate alternative for predicting branch moisture content, it requires destructive sampling. [ABSTRACT FROM AUTHOR]