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The maternal regulation of diapause is one type of phenotypic plasticity where the experience of the mother leads to changes in the phenotype of her offspring that impact how well-suited they will be to their future environment. Sarcophaga bullata females with a diapause history produce offspring that cannot enter diapause even if they are reared in a diapause inducing environment. Accumulating evidence suggests that microRNAs regulate diapause and, possibly, maternal regulation of diapause. We found significant differences in the abundances of several microRNAs (miR-125–5p, miR-124–3p, miR-31–5p, and miR-277–3p) in brains dissected from adult female S. bullata that had experienced diapause compared to females with no diapause history. We also found moderate differences in the mRNA expression of the circadian-clock related genes, clock, clockwork orange, and period. MiR-124–3p and miR-31–5p are part of a gene network that includes these circadian clock-related genes. Taken together our results suggest the maternal block of diapause in S. bullata is regulated, at least in part, by a network that includes microRNAs and the circadian clock.

Beach slope is a critical parameter to, e.g., beach safety, wave reflection at the coast and longshore transport rate. However, it is usually considered as a time-invariant and profile-average parameter. Here, we apply a state-of-the-art equilibrium model to hindcast beach slope variability from the time scales of days to years at the high-energy meso-macrotidal sandy beach of Truc Vert, southwest France. We use 9 years of bimonthly beach surveys to compute beach slope time series at different elevations. Results show that beach slope exhibits an equilibrium response with contrasting behaviors along two distinct areas of the beach profile. From 0 to 2 m above mean sea level, which is located under the berm crest, a slope response predominantly at the storm time scale is observed. The beach slope steepens under low energy waves, with the equilibrium model explaining up to 40% of the observed beach slope variability. In contrast, from 2.5 to 4 m above mean sea level, which is above the berm crest, the beach slope steepens under high-energy waves. Within this region of the beach profile, the response time scale increases upwards from seasonal (~2.5 m) to seasonal (~4 m), with the model explaining up to 65% of the observed beach slope variability. Such behaviors are found to be enforced by the berm dynamics developing from the end of the winter to early autumn, providing new perspectives to model and predict beach slope on sandy beaches. [ABSTRACT FROM AUTHOR]

The maternal regulation of diapause is one type of phenotypic plasticity where the experience of the mother leads to changes in the phenotype of her offspring that impact how well-suited they will be to their future environment. Sarcophaga bullata females with a diapause history produce offspring that cannot enter diapause even if they are reared in a diapause inducing environment. Accumulating evidence suggests that microRNAs regulate diapause and, possibly, maternal regulation of diapause. We found significant differences in the abundances of several microRNAs (miR-125-5p, miR-124-3p, miR-31-5p, and miR-277-3p) in brains dissected from adult female S. bullata that had experienced diapause compared to females with no diapause history. We also found moderate differences in the mRNA expression of the circadian-clock related genes, clock, clockwork orange, and period . MiR-124-3p and miR-31-5p are part of a gene network that includes these circadian clock-related genes. Taken together our results suggest the maternal block of diapause in S. bullata is regulated, at least in part, by a network that includes microRNAs and the circadian clock., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier B.V.)

Beach slope is a critical parameter to, e.g., beach safety, wave reflection at the coast and longshore transport rate. However, it is usually considered as a time-invariant and profile-average parameter. Here, we apply a state-of-the-art equilibrium model to hindcast beach slope variability from the time scales of days to years at the high-energy meso-macrotidal sandy beach of Truc Vert, southwest France. We use 9 years of bimonthly beach surveys to compute beach slope time series at different elevations. Results show that beach slope exhibits an equilibrium response with contrasting behaviors along two distinct areas of the beach profile. From 0 to 2 m above mean sea level, which is located under the berm crest, a slope response predominantly at the storm time scale is observed. The beach slope steepens under low energy waves, with the equilibrium model explaining up to 40% of the observed beach slope variability. In contrast, from 2.5 to 4 m above mean sea level, which is above the berm crest, the beach slope steepens under high-energy waves. Within this region of the beach profile, the response time scale increases upwards from seasonal (~2.5 m) to seasonal (~4 m), with the model explaining up to 65% of the observed beach slope variability. Such behaviors are found to be enforced by the berm dynamics developing from the end of the winter to early autumn, providing new perspectives to model and predict beach slope on sandy beaches.

Snow cover patterns from climate change have profoundly dominated the soil physical structure and biochemical processes in farmland, as global warming is becoming much more serious in recent years. The resulting nutrient loss has posed a great threat to the black soil, a precious soil resource in China. Particularly, most black soils are distributed in seasonally frozen soil areas that are covered by snow all the year round. The snow cover has also some impacts on the black soils in these areas. Similarly, the soil nutrients and enzyme activities have a profound impact on the cycle process of soil materials in the growth and development of crops and grain yields. This study aims to further explore the seasonal response of the available nutrient content and enzyme activity in the black soil to the snow cover removal. Two experimental groups were divided in the study area, including the artificial snow cover removal, and the normal snow cover control group. A seven-month long-term field experiment was carried out to measure the soil temperature, moisture, organic matter content, available nitrogen content, available phosphorus content, invertase activity, and urease activity. The seasonal dynamics were then determined using the measured data. The results showed that the artificial snow removal led to a significant decrease in the soil temperature and soil moisture (P<0.05). At the same time, the artificial snow removal could greatly contribute to making the soil freezing and thawing time earlier, and significantly increased the number of soil freezing and thawing cycles, compared with the normal snow cover control group. In addition, the removal of artificial snow significantly increased the soil organic matter content, soil available nitrogen content, and soil available phosphorus content in early and late winter. However, the contents of soil organic matter, available nitrogen and phosphorus decreased significantly in late winter and early spring. There was also a significant decrease in the two soil enzyme activities of invertase and urease during most of the winter. The snow removal treatment decreased the activities of soil invertase and urease by more than 25.0% and 16.3%, respectively, compared with the normal snow cover control group. In addition, there were some differences in the controlling factors of soil invertase and urease activity in the whole winter and early spring. However, the soil’s available nutrient content was the main controlling factor for the activities of two enzymes during most of the winter. In the future, global warming can lead to the reduction of snow cover in the middle and high latitudes of the world, some of which can have no snow cover, resulting in the different accumulation and release of soil available nutrients. The specific mechanism can be that the reduction of snow cover can cause the rapid accumulation of soil available nutrients in the early winter, and then gradually accumulate in the late winter, resulting in the loss of certain nutrients. This finding can also provide some theoretical support to the soil biochemical evolution under the condition of future climate warming. [ABSTRACT FROM AUTHOR]

In temperate regions of the United States, female Anopheles mosquitoes respond to low temperatures and short photoperiods by entering an overwintering dormancy or diapause. Diapause in Anopheles results in reduced frequency of blood-feeding and reproductive arrest, indicating a period when pathogen transmission by these mosquitoes is unlikely. However, it is unclear precisely how late into the fall and how early in the spring these mosquitoes are biting, reproducing, and potentially transmitting pathogens. This is further complicated by the lack of clear markers of diapause in Anopheles (e.g., changes in egg follicle length). Our goal was to characterize the seasonal reproductive activity of female Anopheles in central Ohio, United States and evaluate egg follicle length as an indicator of Anopheles diapause. We used traditional mosquito traps and aspirators to collect Anopheles from urban woodlots and culverts, respectively, from late September 2021 through mid-May 2022 in central Ohio. By measuring their egg follicle length, reproductive status, and blood-feeding status, we found that egg follicle length is not a reliable indicator of Anopheles diapause. We also found that a small proportion of An. punctipennis (Say), An. perplexens (Ludlow), and An. quadrimaculatus (Say) continued to bite and reproduce into early November 2021 and that females of these species terminated reproductive dormancy and began biting by mid-March 2022. This period of reproductive activity extends beyond current mosquito surveillance and control in Ohio. Our findings suggest that within temperate regions of North America, Anopheles have the capacity to transmit pathogens throughout the spring, summer, and fall., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

This year marks the 100th anniversary of the experiments by Garner and Allard that showed that plants measure the duration of the night and day (the photoperiod) to time flowering. This discovery led to the identification of Flowering Locus T (FT) in Arabidopsis and Heading Date 3a (Hd3a) in rice as a mobile signal that promotes flowering in tissues distal to the site of cue perception. FT/Hd3a belong to the family of phosphatidylethanolamine-binding proteins (PEBPs). Collectively, these proteins control plant developmental transitions and plant architecture. Several excellent recent reviews have focused on the roles of PEBPs in diverse plant species; here we will primarily highlight recent advances that enhance our understanding of the mechanism of action of PEBPs and discuss critical open questions. [ABSTRACT FROM AUTHOR]

Ticks are a growing concern to human and animal health worldwide and they are leading vectors of arthropod-borne pathogens in the United States. Ticks are pool blood feeders that can attach to the host skin for days to weeks using their saliva to counteract the host defenses. Tick saliva, as in other hematophagous arthropods, contains pharmacological and immunological active compounds, which modulate local and systemic immune responses and induce antibody production. In the present study, we explore differences in the salivary gland extract (SGE) protein content of Amblyomma americanum ticks raised in a laboratory colony (CT) vs. those collected in the field (FT). First, we measured the IgG antibody levels against SGE in healthy volunteers residing in Kansas. ELISA test showed higher IgG antibody levels when using the SGE from CT as antigen. Interestingly, antibody levels against both, CT-SGE and FT-SGE, were high in the warm months (May–June) and decreased in the cold months (September–November). Immunoblot testing revealed a set of different immunogenic bands for each group of ticks and mass spectrometry data revealed differences in at 19 proteins specifically identified in the CT-SGE group and 20 from the FT-SGE group. Our results suggest that differences in the salivary proteins between CT-SGE and FT-SGE may explain the differential immune responses observed in this study.

Abstract: Temperate forest ecosystems have experienced mounting negative effects due to increasing levels of nitrogen (N) deposition. We examined the effects of experimental N addition on plant diversity in an old‐growth temperate forest to test the following hypothesis: Long‐term excessive N addition decreases plant diversity by affecting the growth of plants, which results from changes in the soil nutrient content and a decrease in the soil pH in temperate forests. Experimental N additions were administered at the following levels since 2008: control (0 kg N ha−1 year−1), low N (30 kg N ha−1 year−1), medium N (60 kg N ha−1 year−1), and high N (120 kg N ha−1 year−1). Additionally, plant diversity was studied from 2014 to 2016. The results showed that the experimental N additions had significant effects on plant diversity and soil properties in an old‐growth temperate forest. The high‐N treatment decreased the density, cover, and diversity of understory plants, and some herbs even appeared to undergo premature aging, whereas the species diversity of herbs and ferns in the low‐N treatment plots showed a slight increasing tendency. This may have been because the old‐growth temperate forest is an N‐limited ecosystem, so the moderate N input did not show a large influence on plant diversity. However, the long‐term high‐N treatment ultimately reduced plant diversity by changing the soil nutrient contents, decreasing the pH values, and damaging plant growth. Our results suggested that the long‐term excessive N addition negatively affected the forest ecosystem in an N‐limited temperature forest. [ABSTRACT FROM AUTHOR]

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The harsh and stressful growing environment of extensive green roofs especially in arid environments allows a limited range of plant species to survive. Therefore, achieving plantings to survive in such conditions is a significant challenge. This paper describes an experiment investigating plant selections for extensive green roofs based on chilling (cold season) and drought (warm season) conditions of Iran. Nine species were selected from the three major taxonomic and functional plant groups that are commonly used on extensive green roofs including grasses, groundcovers and sedums. The species namely Agropyron cristatum , Festuca aurundinacea , Festuca ovina , Potentila sp., Frankinia thymifolia , Vinca minor , Sedum acre , Sedum spurinum , Carpobrotus edulis were imposed to natural chilling in autumn and winter using a randomized complete block design. For spring and summer, irrigation regimes at levels (48, 72 and 96 h intervals) in a factorial experiment based on a randomized complete block design with four replications were applied. The results showed that Agropyron cristatum , Frankinia thymifolia and Carpobrotus edulis were the best plants from each class. Carpobrotus edulis was the best choice for cold and warm seasons and this was followed by Frankinia thymifolia and Potentila sp. Vinca minor performed well in the cold seasons and Sedum spurinum appeared to be excellent in the warm seasons. The plants of the experiment showed significantly different appearances in different watering regimes. Little differences in drought tolerances were observed among the forbs and grasses, which must be watered during warm seasons. However, the succulents responded very well to the drought and low watering regimes. Overall, succulents and groundcovers were considered more appropriate for application in warm and cold seasons, respectively. According to the findings, drought and cold weather conditions cannot be a major obstacle for developing extensive green roofs in Iran if considerations are made on selecting its plant species. [ABSTRACT FROM AUTHOR]

The flower-galling mite, Aceria lantanae (Cook) (Acari: Trombidiformes: Eriophyidae), was released as a biological control agent of Lantana camara L. (Verbenaceae) in the Limpopo, Mpumalanga, Gauteng and KwaZulu-Natal provinces of South Africa, between 2007 and 2012. Flower galls were subsequently observed at several sites where the mite had not been released, providing evidence of dispersal. This study was therefore conducted to determine the establishment, seasonal performance and dispersal rate of A. lantanae in the aforementioned South African provinces and neighbouring Swaziland. The effect of A. lantanae along with the other previously-established biological control agents on inflorescence and seed production of susceptible L. camara varieties was determined by insecticide exclusion experiments in the field. Aceria lantanae became established at 58.6% of the original release sites located in the four provinces. The mite has also established widely within the geographic range of L. camara in South Africa and Swaziland, with dispersal rates of up to 40.6 km per annum. Infestations of inflorescences varied substantially between sites, provinces and seasons and ranged from 2.7% to 97%. Inflorescence and seed production declined significantly by up to 97% and 94%, respectively, on untreated biological control stands compared to the insecticide-treated exclusion stands. Although A. lantanae has become widespread within the geographic range of L. camara in South Africa, different L. camara plants appeared to vary in their susceptibility to A. lantanae , suggesting that genetic differences among plants may have affected the performance of the mite. If this is true, additional mite strains will be required to control resistant varieties. [ABSTRACT FROM AUTHOR]

• Summer droughts led to the greatest decline in LAI, GPP, and NEP. • Climatic factors dominated spring and autumn GPP response, but not in summer. • Carry-over effects from previous seasons compensated for subsequent drought impacts. Droughts affect the interannual variability of global land carbon fluxes and are expected to exert widespread impacts on the carbon cycle given a future climate with more intense and frequent droughts. Evidence indicates that the impacts of droughts on the carbon cycle vary in different seasons, but a quantitative examination of the seasonal differences is lacking. Here we ensemble multiple data streams for greenness indices and carbon fluxes, including those from remote sensing observations, flux tower upscaling, atmospheric inversions, and dynamic global vegetation models (DGVMs), to quantify the seasonal responses of vegetation to extreme droughts in China. We find that summer droughts cause the largest negative responses of leaf area index (LAI, with median standardized anomalies of -0.40), gross primary productivity (GPP, -0.55), and net ecosystem productivity (NEP, -0.74); notably, droughts in autumn largely suppress carbon uptake. The response patterns show a high degree of heterogeneity, and we identify the factors driving these spatial variations using the extreme gradient boosting (XGBoost) machine learning approach. Climate is the dominant driver of spring and autumn GPP responses while LAI predominantly drives summer GPP loss. Looking into the biotic factors, carry-over effects (previous-season vegetation growth affecting current-season growth) contribute substantially to the alleviation of drought stress, in that previous-season greening compensate vegetation loss during droughts. Our results not only quantify the seasonal response differences in carbon fluxes and greenness, but suggest that carbon fluxes respond more sensitively to drought than greenness. Also, we show seasonal differences in the degree to which factors contribute to drought impacts, which highlight that annual-scale drought analyses may mask spring and autumn vegetation response to droughts. [ABSTRACT FROM AUTHOR]

Seasonal variation in the response of riverine microbial communities to an environmentally relevant exposure to glyphosate (about 10μgl−1) was assessed on natural communities collected in spring and summer, using two 14-day microcosm studies. The two experiments showed no major effect of glyphosate on algal biomass (chlorophyll a concentrations), bacterial activity ([3H]thymidine incorporation), or bacterial community diversity (16S PCR-TTGE detection). Effects on algal community composition (genus-level taxonomic identification) and eukaryotic community diversity (18S PCR-DGGE on <100μm organisms) were only detected on the samples collected in summer. This work demonstrates that even if the effects of a short pulse of glyphosate (10μgl−1) on riverine microorganisms seem to be limited, the responses of natural microbial communities to glyphosate exposure (and probably to other pesticide exposures) can clearly vary between the experiments, and can be seasonally dependent. [Copyright &y& Elsevier]

Abstract: The extraction of induced oleoresin from Pinus elliottii through bark streaking supplies products to the food, pharmaceutical and chemical industries. Resin flow is a typical defense response in conifers and is controled by various environmental factors. Although many studies have focused on oleoresin production in temperate forests, particularly in response to bark beetle attacks, relatively little is known about the physiological regulation of sustainable resin exudation in subtropical planted forests, in which commercial exploitation of this product is favored by the absence of significant pest insect populations. Therefore, the annual oleoresin yield of approximately 2660, 28-year-old trees from different sites was monitored for two consecutive years in southern Brazil. Plain wounding and wounding followed by application of a commercial resin stimulant paste containing the ethylene precursor 2-chloroethylphosphonic acid (CEPA) were used as reference treatments. Different concentrations of auxin, paraquat, yeast extract, and salicylic acid (isolated or in combination with CEPA) were also tested. Higher resin yields were associated with spring and summer, whereas winter had lower but significant yields. Auxin and salicylic acid stimulated the production of oleoresin relative to commercial paste in at least one concentration. Replacement of CEPA with auxin or salicylic acid yielded equivalent oleoresin production, indicating a comparable or complementary effect of these molecules in the process, as well as having implications for new stimulant paste formulations. [Copyright &y& Elsevier]

Abstract: Benthic foraminifera are widely used tools to reconstruct paleoenvironments. They reflect bottom water oxygen concentrations and organic carbon flux. To increase their accuracy as proxies, seasonal variability of foraminiferal populations from the outer shelf of the Bay of Biscay (150m water depth) was followed over a 3-year period. The selected area is characterized by seasonal variation in organic matter deposition. A strong interaction between organic detritus input, macrofaunal bioturbational activity, the degree of separation of redox zones and the reproduction, growth and migrational response of benthic foraminifera was found. During periods of high labile organic matter input, as occurs during spring bloom conditions, the redox zonation was not well established. Different organic degradation pathways occurred at the same depth intervals in the sediment. Shallow infaunal species reacted in response to the high nutrient content with rapid growth (Bolivina subaenariensis) or reproduction (Epistominella vitrea, Bolivina seminuda, Bolivina dilatata/spathulata). Infaunally living foraminifera, Chilostomella oolina and to lesser extent Nonion scaphum, migrated to the sediment surface in reaction the increase organic matter input to the seafloor. This migration could have been induced by the more intensive overlapping of redox zones that were perhaps better separated vertically in winter. However, this migration could also have been triggered by the occurrence of fresh phytodetritus in the sediment, becoming even available in slightly deeper sediment level due to the increased bioturbation activity. [Copyright &y& Elsevier]

Questions: How does the seed bank respond to different types of tree-fall gaps and seasonal variations? How does the soil seed bank influence recovery of the standing vegetation in the mature forest and tree-fall gaps? Location: 1800 - 2020 m a.s.l., Quercus-Pinus forest, Baja California Sur, Mexico. Methods: Seed size, species composition and germination were estimated under different environmental conditions during dry and rainy seasons: a mature forest plot and gaps created by dead standing trees, snapped-off trees and uprooted trees. The soil seed bank was investigated using direct propagule emergence under laboratory conditions, from soil cores obtained during both seasons. Results: 21 species, 20 genera and 14 families constitute the seed bank of this forest community. Fabaceae, Asteraceae, Euphorbiaceae and Lamiaceae were the most frequently represented families in the seed bank. Floristic composition and species richness varied according to the different modes of tree death. Species composition of seed banks and standing vegetation had very low similarity coefficients and were statistically different. Seed bank sizes varied between 164 and 362 ind.m-2 in the mature forest plot for the dry and rainy seasons, respectively, while soil seed bank sizes for gaps ranged between 23-208 ind.m-2 for the dry season and between 81-282 ind.m-2 for the rainy season. Conclusions: Seed bank sizes and germination response were always higher in the rainy season under all the environmental conditions analysed. Results suggest that timing responses to gap formation of the soil seed bank could be more delayed in this temperate forest than expected. [ABSTRACT FROM AUTHOR]

Microbial biomass, size and community structure along with an estimate of microbial activity and soil chemical parameters were determined at three depths in two soils (e.g. sandy loam Ultic Hapludalf and silt loam Mollic Hapludalf) replicated three times under one winter and summer season. Microbial biomass and community structure were estimated from phospholipid-PO4 content and fatty acid methyl ester (FAME) measurements. Microbial activity and assimilative capacity were estimated using a 3H-acetate incorporation into phospholipids and by incubating the soil samples at the average winter and summer temperatures, 3 and 20 °C, respectively. We found that the size of the microbial biomass in both the surface and the subsurface soils was not significantly affected by the seasonal variation but activity increased by as much as 83% at the summer temperatures in the surface soil. We demonstrated using FAME analysis that for both soils seasonal changes in the subsurface microbial community occurred. These findings suggest that winter conditions will shift the population activity level in both the surface and subsurface systems and the biochemical structure of the community in the subsurface. In all cases, the inorganic chemical properties of the soil, as a function of season, remained constant. The greatly increased activity of microbial population at the higher temperature will favor the capacity of the system to utilize nutrients or organic materials that may enter soil. During low temperature seasons the capacity of either surface or subsurface soils to assimilate materials is generally diminished but the reduction reflects changes in metabolism and not a reduced biomass size. [Copyright &y& Elsevier]

Six-year-old Scots pine ( Pinus sylvestris L.) seedlings were grown in open top chambers (OTCs) at ambient (AC) or elevated (ambient + 400 µmol mol−1; EC) CO2 concentration for three years (1996–1998). Chlorophyll (Chl) a fluorescence of current and one-year-old needles was measured in the field at two-weekly intervals in the period July–October 1998. In addition, Chl, carbon (C), and nitrogen (N) concentrations in both needle age classes were determined monthly during the same period. Chl fluorescence parameters were not significantly affected by EC, suggesting there was no response of the light reactions and the photochemical efficiency of photosystem 2. Chl concentrations were not significantly different but a reduced N concentration was observed in needles of EC treatment. Significant differences between needle age classes were observed for all parameters, but were most apparent under EC and toward the end of the growing season, possibly due to an acclimation process. As a result, significant interactions between CO2 treatment, needle age class, and season were found. This study emphasizes the importance of repeated measures including different leaf/needle age classes to assess the photosynthetic response of trees under EC. [ABSTRACT FROM AUTHOR]

Five-year-old Scots pine (Pinus sylvestrisL.) seedlings were grown in open-top chambers at ambient and elevated (ambient + 400 μmol mol−1) CO2 concentrations. Net photosynthesis (A), specific leaf area (SLA) and concentrations of nitrogen (N), carbon (C), soluble sugars, starch and chlorophyll were measured in current-year and 1-year-old needles during the second year of CO2 enrichment. The elevated CO2 treatment stimulated photosynthetic rates when measured at the growth CO2 concentration, but decreased photosynthetic capacity compared with the ambient CO2 treatment. Acclimation to elevated CO2 involved decreases in carboxylation efficiency and RuBP regeneration capacity. Compared with the ambient CO2 treatment, elevated CO2 reduced light-saturated photosynthesis (when measured at 350 μmol mol−1 in both treatments) by 18 and 23% (averaged over the growing season) in current-year and 1-year-old needles, respectively. We observed significant interactive effects of CO2 treatment, needle age and time during the growing season on photosynthesis. Large seasonal variations in photosynthetic parameters were attributed to changes in needle chemistry, needle structure and feedbacks governed by whole-plant growth dynamics. Down-regulation of photosynthesis was probably a result of reduced N concentration on an area basis, although a downward shift in the relationship between photosynthetic parameters and N was also observed. [ABSTRACT FROM PUBLISHER]

Atmospheric nitrogen (N) deposition and increasing precipitation affect carbon sequestration in terrestrial ecosystems, but how these two concurrent global change variables affect xylem growth in trees (i.e., independently or interactively) remains unclear. We conducted novel experiments in central China to monitor the xylem growth in a dominant species (Quercus acutissima Caruth.) in response to N addition (CN), supplemental precipitation (CW) or both treatments (CNW), compared with untreated controls (C). Measurements were made at weekly intervals during 2014-15. We found that supplemental precipitation significantly enhanced xylem growth in the dry spring of 2015, indicating a time-varying effect of increased precipitation on intra-annual xylem growth. Elevated N had no significant effect on xylem increment, xylem growth rate, and lumen diameters and potential hydraulic conductivity (Ks) of earlywood vessels, but Ks with elevated N was significantly negatively related to xylem increment. The combination of additional N and supplemental precipitation suppressed the positive effect of supplemental precipitation on xylem increment in the dry spring of 2015. These findings indicated that xylem width was more responsive to supplemental precipitation than to increasing N in a dry early growing season; the positive effect of supplemental precipitation on xylem growth could be offset by elevated N resources. The negative interactive effect of N addition and supplemental precipitation also suggested that increasing N deposition and precipitation in the future might potentially affect carbon sequestration of Q. acutissima during the early growing season in central China. The effects of N addition and supplemental precipitation on tree growth are complex and might vary depending on the growth period and local climatic conditions. Therefore, future models of tree growth need to consider multiple-time scales and local climatic conditions when simulating and projecting global change., (© The Author(s) 2021. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The function of a building is to provide not just shelter and comfort, but to actively promote a healthy physiology. In reviewing the fields of environmental medicine and biometereology the authors propose that as buildings provide the main climate that people live in, this may affect seasonal response and could be a prime causal agent for ill health and 'sick building syndrome'. Flexible and seasonal changes of building use are introduced and parallels are drawn with marine environments for relearning physiological systems of adaptation. Conclusions include a rationale for looking at health problems within buildings by utilizing bodies of knowledge that already make useful links between climate and health. If this knowledge can be used as a predictive tool in the design and control of the built environment then it could make a significant impact on health and assist strategic decision-making in allocating resources towards an 'engineered' health care environment, as a major factor in primary health care. La fonction d'un batiment n'est pas seulement d'offrir un abri confortable mais aussi de favoriser une physiologie saine. Les auteurs passent en revue les differents domaines de la medecine environnementale et de la biometerorologie et expliquent que les batiments constituant le principal 'climat' dans lequel on vit, cette situation risque d'affecter les reactions saisonnieres et pourrait etre un agent etiologique principal de maladies et du syndrome des batiments malsains. Ils proposent que l'on modifie en souplesse l'usage des batiments en fonction des saisons et tracent un parallele avec les environnements marins en matiere de reapprentissage de systemes physiologiques d'adaptation. En conclusion, ils presentent notamment un expose raisonne portant sur l'examen des problemes de sante a l'interieur des batiments on utilisant des blocs de connaissances qui etablissent deja des liens utiles entre le climat et la sante. Si ces connaissances peuvent servir d'outil de prevision pour la conception et le controle de l'environnement construit, elles pourraient avoir des incidences non negligeables sur la sante et permettraint de prendre plus facilement des decisions d'ordre strategique en affectant des ressources a un environnement amenage de soins de sante, ce qui constituerait un element majeur des soins de sante primaires. [ABSTRACT FROM AUTHOR]

The short days of late summer and early fall are the environmental cues that most temperate insects and other animals use to predict winter's arrival. Although it is still unclear precisely how insects measure daylength, there is mounting evidence that the circadian clock regulates seasonal responses including photoperiodic diapause. Females of the Northern house mosquito, Culex pipiens , enter an adult reproductive diapause in response to short daylengths. While in this state, females divert their resources from reproduction to survival, arresting egg follicle development and increasing fat content. Here, we characterized the expression profile of two circadian transcription factors, vrille (vri) and Par domain protein 1 (Pdp1), as well as genes downstream of the clock, takeout (to) and Nocturnin (Noc) and under different seasonal conditions. We saw that while vri mRNA oscillated under both long day and short day conditions, Pdp1 expression oscillated only under long day conditions and was constitutively upregulated in diapausing females. We saw similar expression profiles for to and Noc , suggesting that PDP1 might regulate their expression or that Pdp1 , to and Noc might be regulated by the same transcription factor. We suppressed vri and Pdp1 using RNA interference. dsRNA against vri provided inconsistent results, sometimes stimulating autogenous egg follicle development in both long and short day-reared females, and other times had no effect. In contrast, knocking down Pdp1 prevented short day-reared females from accumulating fat reserves, but increased expression of to and Noc. Taken together, these data suggest that the circadian transcription factors Vri and Pdp1 may independently regulate signaling pathways underlying arrested egg follicle development and fat accumulation in diapausing females of Cx. pipiens. Image 1 • The role of circadian transcription factors Vr and Pdp1 in diapause was examined in females of Culex pipiens. • vri mRNA oscillated in brains of nondiapausing and diapausing mosquitoes; pdp1 was constitutively upregulated in the latter. • RNAi directed against vri stimulated egg development in some females, while pdp1 dsRNA prevented short day females from acquiring fat. • Vri and Pdp1 might independently regulate seasonal differences in reproduction and metabolism in Cx. pipiens. [ABSTRACT FROM AUTHOR]

Air pollution has been considered as one of the most important factors associating with various birth outcomes. However, the seasonal response of maternal comorbidities effects associated with air pollution has not been investigated, especially in the city with distinguish seasonal pattern and long heating seasons. In this work, 69,945 live births were investigated from 2013 to 2016, and the seasonal relationship between air pollution and preterm birth and low birth weight were assessed, as well as the synergism of maternal comorbidities. Exposures of six pollutants were assigned to maternal residences during pregnancy. The potential effect modification by maternal comorbidities on the associations was evaluated between prenatal air pollution and preterm birth (PTB), as well as effects of seasons and trimesters. Adjusting for seasonality, all six pollutants presented seasonal relationship with preterm birth, which CO, PM 10 , NO 2 , and PM 2.5 were with [odds ratio (OR) = 1.035 95% CI: 1.015, 1.055, OR = 1.039 95% CI: 1.034, 1.045, OR = 1.042, 95% CI: 1.029, 1.056 and OR = 1.085 95% CI 1.073, 1.097, respectively] for tenth quartile of 10 μg/m3 range increased in autumn (the beginning of heating season). For O 3 , it associated with PTB in winter and spring with OR = 1.113 95% CI: 1.104, 1.123, and OR = 1.155 95% CI: 1.145, 1.165, respectively. The OR increase of PTB for exposure to all six pollutants was higher among women with preeclampsia and gestational hypertension. The associations between ambient air pollution and preterm birth were modified by gestational hypertension and preeclampsia. The seasonal patterns of six studied air pollutants increases the risk of PTB in autumn and winter distinguishably, which may due to the sudden increased concentrations of pollutants emitted by traditional heating. The seasonal response of the synergism of maternal comorbidities and long-term air pollution exposure on birth outcomes is supported by the data sets of preterm birth. Image 1 • The seasonal response of maternal comorbidities effects with air pollution was investigated. • The associations between air pollution and PTB were modified by gestational hypertension and preeclampsia. • The seasonal patterns of six studied air pollutants increased the risk of PTB in autumn and winter distinguishably. • The seasonal response of PTB associated with the synergism of maternal comorbidities and long-term air pollution exposure. [ABSTRACT FROM AUTHOR]

We investigated the temperature effects on hypothalamic transcription of genes involved in the induction of photoperiodic response in redheaded buntings. Birds were exposed at 22 and 38 °C to 13-h long photoperiods (LP), with controls at 22 °C on 8-h short photoperiods (SP). At 22 °C, compared to SP, we found higher tshb , eya3 and dio2 and low dio3 and gnih mRNA expressions after a week of LP; concomitant with testis recrudescence this confirmed buntings' responsiveness to LP-induced photostimulation. tshb , dio2 and gnrh mRNA levels were further increased by 2.5 weeks of LP at 38 °C. Temperature sensitive trpm8 , but not trpv4 , bdnf or adcyap1 also showed LP-induced expression at 22 °C. Concomitant changes in dnmt3b and tet2 mRNA expressions further suggested epigenetic modification of temperature influence on photoperiodic responses. These results demonstrate the role of temperature in hypothalamic molecular regulation of the photoperiodic gonadal response in seasonally breeding birds. • Temperature-dependence of hypothalamic TH-responsive photoperiodic genetic cascade. • Testes grew faster under 38 °C than 22 °C in buntings exposed to long days. • Increased tshb , dio2 and gnrh gene expressions with long day exposure at 38 °C. • Differential expression of temperature sensitive trpm8 gene under long days. • Dnmt3b and tet2 expressions suggest epigenetic modification of gonadal response. [ABSTRACT FROM AUTHOR]

Ticks are a growing concern to human and animal health worldwide and they are leading vectors of arthropod-borne pathogens in the United States. Ticks are pool blood feeders that can attach to the host skin for days to weeks using their saliva to counteract the host defenses. Tick saliva, as in other hematophagous arthropods, contains pharmacological and immunological active compounds, which modulate local and systemic immune responses and induce antibody production. In the present study, we explore differences in the salivary gland extract (SGE) protein content of Amblyomma americanum ticks raised in a laboratory colony (CT) vs. those collected in the field (FT). First, we measured the IgG antibody levels against SGE in healthy volunteers residing in Kansas. ELISA test showed higher IgG antibody levels when using the SGE from CT as antigen. Interestingly, antibody levels against both, CT-SGE and FT-SGE, were high in the warm months (May-June) and decreased in the cold months (September-November). Immunoblot testing revealed a set of different immunogenic bands for each group of ticks and mass spectrometry data revealed differences in at 19 proteins specifically identified in the CT-SGE group and 20 from the FT-SGE group. Our results suggest that differences in the salivary proteins between CT-SGE and FT-SGE may explain the differential immune responses observed in this study.

Regional-scale normalized difference vegetation index (NDVI) derived from satellite remote sensing observations and gridded climate data were used to study the seasonal responses and underlying mechanisms of vegetation growth over Tibetan Plateau to Pacific Decadal Oscillation (PDO) at period of 1982-2015, by performing Spearman correlation analysis and enhanced multivariate regression model: structural equation model (SEM). The results showed that there was significant negative correlation between PDO index and mean growing-season (April-October) NDVI over Tibetan Plateau; however, marked seasonal divergence in the relationship between PDO and vegetation growth existed among different seasons. It characterized with stronger negative correlation between PDO and NDVI in autumn than in summer, and winter PDO had significant effect on consequent summer vegetation growth. Additionally, it showed great divergence in control processes of PDO on vegetation growth among different seasons, with significant control of PDO on both temperature and precipitation in summer, and significant control of PDO on temperature only in autumn.