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1.
Braz. j. biol ; 84: e257969, 2024. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1364513

ABSTRACT

In this study, we evaluated variation in vegetative and reproductive phenological events of four phylogenetically related plant species subjected to a seasonal environment. To this aim, we sampled 15 individuals of each plant species every fortnight for one year, between January and December of 2017. To assess when a given phenophase occurred more intensely in the population, the Fournier intensity index was used and the synchrony of individuals of the sample in a given phenological event was estimated using the activity index. The Rayleigh (Z) test was used to determine whether the phenological events have seasonal distribution. The relationship of abiotic factors (photoperiod, precipitation, relative humidity and temperature) with the intensity of phenophases was evaluated for each plant species using generalized linear models (GLMs). The phenophases of all plants showed a seasonal distribution pattern, as well as variation in synchrony of phenophases and specific sets of abiotic factors significantly influenced their phenophases. New leaves, for example, were produced throughout the seasons, with intense leaf fall in the dry season. Flowering periods, on the other hand, did not overlap. Indeed, species exhibited sequential flowering and asynchronous flowering among individuals. Our results suggest that the phenological patterns of four sympatric plant species are directly linked to climatic variables, but different abiotic factors affected different phenophases.


Neste estudo, avaliamos a variação nos eventos fenológicos vegetativos e reprodutivos de quatro espécies de plantas filogeneticamente relacionadas submetidas a um ambiente sazonal. Para isso, amostramos 15 indivíduos de cada espécie quinzenalmente, pelo período de um ano, entre janeiro e dezembro de 2017. Para avaliar quando uma determinada fenofase ocorreu de modo mais intenso na população foi utilizado o índice de intensidade de Fournier e a sincronia dos indivíduos da amostra em determinado evento fenológico foi estimada utilizando-se o índice de atividade. O teste de Rayleigh (Z) foi usado para determinar se os eventos fenológicos têm distribuição sazonal. A relação dos fatores abióticos (fotoperíodo, precipitação, temperatura e umidade relativa) com a intensidade das fenofases foi avaliada para cada espécie de planta usando modelos lineares generalizados (GLMs). As fenofases de todas as plantas apresentaram um padrão de distribuição sazonal, bem como variação na sincronia das fenofases e conjuntos específicos de fatores abióticos influenciaram significativamente suas fenofases. Folhas novas, por exemplo, foram produzidas ao longo das estações, com intensa queda de folhas na estação seca. Os períodos de floração, por outro lado, não se sobrepuseram. De fato, as espécies exibiram floração sequencial e floração assíncrona entre os indivíduos. Nossos resultados sugerem que os padrões fenológicos das quatro espécies de plantas simpátricas estão diretamente ligados às variáveis climáticas, mas diferentes fatores abióticos afetaram diferentes fenofases.


Subject(s)
Plantes , Saisons , Croissance et développement , Environnement , Sympatrie/physiologie
2.
Braz. j. biol ; 84: e254174, 2024. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1360213

ABSTRACT

Anredera cordifolia (Ten.) Steenis is a vine species native to Brazil that is considered an unconventional food plant and a medicinal species whose phenolic compounds exert antioxidant activity. Since the production of metabolites is determined by environmental factors and leaf maturity, it is important to track these changes in order to determine the best time to harvest. This study aimed to verify whether leaf phenology and seasonality cause variations in the amount of phenolic compounds and in the antioxidant activity of this species. The leaves were collected in different seasons between September 2018 and April 2019, and separated according to maturity: young, mature, and senescent. Daily atmospheric temperature and rainfall data were used to characterize the collection period. The total phenolic content (TPC), determined by Folin-Ciocalteu method, was significantly higher in the young leaves collected in winter, a season of lower temperatures. These leaves showed 54.4 mg of gallic acid equivalents per 100 g of dry matter (mg GAE 100 g-1DM). Other results averaged 25.6 mg GAE 100 g-1DM. The highest antioxidant activity, assessed via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, regardless of leaf phenology, was observed in leaves harvested in autumn (73.7%) and winter (71.1%), seasons with lower rainfall. Leaves harvested in summer and spring had lower antioxidant action rates (54.3 e 37.5%, respectively). There was no significant correlation between the total phenolic content and antioxidant activity. Thus, the phenolic composition of A. cordifolia, and consequently its activity on free radicals, varies seasonally in response to temperature and rainfall, and may or may not interact with the age of the leaves.


Anredera cordifolia (Ten.) Steenis é uma trepadeira nativa do Brasil considerada uma planta alimentícia não convencional e uma espécie medicinal, cujos compostos fenólicos exercem ação antioxidante. Como a produção de metabólitos é determinada por fatores ambientais e pela maturidade das folhas, é importante acompanhar essas mudanças a fim de determinar a época de colheita. Neste estudo objetivou-se verificar se a fenologia foliar e a sazonalidade ocasionam variação na quantidade de compostos fenólicos e na ação antioxidante dessa espécie. As folhas foram coletadas em diferentes estações, entre setembro de 2018 e abril de 2019, e separadas conforme a maturidade: jovens, maduras e senescentes. Os dados diários de temperatura atmosférica e pluviosidade foram usados para caracterizar o período de coleta. O conteúdo de fenólicos totais (TPC), determinado pelo método Folin-Ciocalteu, foi significativamente maior nas folhas jovens coletadas no inverno, período caracterizado por temperaturas mais baixas. Estas folhas apresentaram 54,4 mg equivalentes de ácido gálico por 100 g de matéria seca (mg GAE 100 g-1DM) . A média dos outros resultados foi de 25,6 mg GAE 100 g-1DM. A maior ação antioxidante, avaliada pelo método do radical livre 2,2-difenil-1-picrilhidrazil (DPPH), foi observada em folhas colhidas no outono (73,7%) e inverno (71,1%), independentemente da fenologia foliar. Nestes períodos a pluviosidade foi menor. Folhas colhidas no verão e na primavera apresentaram menores percentuais de ação antioxidante (54,3 e 37,5%, respectivamente). Não houve correlação significativa entre o conteúdo de fenólicos totais e a atividade antioxidante. Conclui-se que a composição fenólica de A. cordifolia e, consequentemente, sua ação sobre radicais livres, varia sazonalmente em resposta à temperatura e pluviosidade, podendo ou não interagir com a idade das folhas.


Subject(s)
Plantes médicinales/croissance et développement , Saisons , Composés Phénoliques , Antioxydants
3.
Braz. j. biol ; 84: e251438, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1345560

ABSTRACT

Abstract The northwestern portion of the Upper Paraná Atlantic Forest ecoregion is one of the most disturbed and fragmented areas in the Atlantic Forest, and little is known about the local avifauna. In this study, we have described the composition and diversity of the aquatic avifauna of this region and analyzed the patterns of similarity with respect to the seasonal as well as spatial distribution. We used the line transect sampling technique in six distinct humid areas (including lentic and lotic water bodies) during the dry and rainy seasons of 2012 and 2013. A total of 52 species of waterfowl were recorded. The species richness of the studied areas was surprisingly distinct; only seven waterfowl species, namely Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764), were common to these six studied areas. This indicated that the other bird species that were observed might be habitat selective. Moreover, the analysis of the composition of birds in the two seasons (dry and rainy) combined with their spatial distributions showed significant dissimilarities between the areas with lotic (river and constructed wetland) and lentic (lagoons) characteristics. Nevertheless, despite the small extent and low total richness of the entire study area, it was found to be home to 1/3 of all freshwater aquatic birds documented in the state of São Paulo, with the record of 5 migratory species and 11 new species added to the northwest of the state. The heterogeneity of local aquatic environments, habitat selection combined with seasonality, and the absence of other humid locations in the surroundings can explain the diversity and distribution of these birds in the water bodies of this uninvestigated Atlantic Forest ecoregion.


Resumo A porção noroeste da ecorregião Floresta Atlântica do Alto Paraná é uma das mais alteradas e fragmentadas da Mata Atlântica, da qual pouco se sabe sobre a avifauna local. Nosso objetivo foi descrever a diversidade e composição da avifauna aquática, bem como analisar os padrões de similaridade quanto a distribuição temporal e espacial destas aves nesta ecorregião. Utilizamos a transecção linear para amostragem em seis áreas úmidas (corpos d'água lênticos e lóticos), nos períodos de seca e chuva entre 2012 e 2013. Registramos 52 espécies de aves aquáticas e as riquezas das áreas mostraram-se distintas, pois apenas Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764) foram comuns às seis áreas, o que indica seleção de habitat. Quando analisada a composição das aves nos dois períodos aliada à distribuição espacial, encontramos dissimilaridades temporais acentuadas entre os ambientes com características lóticas (rio e aterro) e lênticas (lagoas). Isto mostra que, além das diferentes épocas sazonais, é necessário analisar separadamente os diferentes tipos de áreas úmidas. Por fim, apesar da extensão pequena e baixa riqueza total, a área amostrada abrigou 1/3 das aves aquáticas de água doce para o estado de São Paulo, cinco espécies migratórias e 11 novas espécies para o noroeste do estado. A heterogeneidade de ambientes aquáticos locais, forte seleção de habitat aliada à sazonalidade e ausência de outros locais úmidos em seu entorno, explicam a diversidade e distribuição destas aves estreitamente relacionadas aos corpos d'água desta desconhecida ecorregião da Mata Atlântica.


Subject(s)
Animaux , Oiseaux , Biodiversité , Saisons , Brésil , Forêts , Écosystème
4.
Braz. j. biol ; 84: e257402, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355856

ABSTRACT

Abstract Visceral leishmaniasis (VL) is an infectious disease predominant in countries located in the tropics. The prediction of occurrence of infectious diseases through epidemiologic modeling has revealed to be an important tool in the understanding of its occurrence dynamic. The objective of this study was to develop a forecasting model for the incidence of VL in Maranhão using the Seasonal Autoregressive Integrated Moving Average model (SARIMA). We collected monthly data regarding VL cases from the National Disease Notification System (SINAN) corresponding to the period between 2001 and 2018. The Box-Jenkins method was applied in order to adjust a SARIMA prediction model for VL general incidence and by sex (male or female) for the period between January 2019 and December 2013. For 216 months of this time series, 10,431 cases of VL were notified in Maranhão, with an average of 579 cases per year. With regard to age range, there was a higher incidence among the pediatric public (0 to 14 years of age). There was a predominance in male cases, 6437 (61.71%). The Box-Pierce test figures for overall, male and female genders supported by the results of the Ljung-Box test suggest that the autocorrelations of residual values act as white noise. Regarding monthly occurrences in general and by gender, the SARIMA models (2,0,0) (2,0,0), (0,1,1) (0,1,1) and (0,1,1) (2, 0, 0) were the ones that mostly adjusted to the data respectively. The model SARIMA has proven to be an adequate tool for predicting and analyzing the trends in VL incidence in Maranhão. The time variation determination and its prediction are decisive in providing guidance in health measure intervention.


Resumo A leishmaniose visceral (LV) é uma doença de natureza infecciosa, predominante em países de zonas tropicais. A predição de ocorrência de doenças infecciosas através da modelagem epidemiológica tem se revelado uma importante ferramenta no entendimento de sua dinâmica de ocorrência. O objetivo deste estudo foi desenvolver um modelo de previsão da incidência da LV no Maranhão usando o modelo de Média Móvel Integrada Autocorrelacionada Sazonal (SARIMA). Foram coletados os dados mensais de casos de LV através do Sistema de Informação de Agravos de Notificação (SINAN) correspondentes ao período de 2001 a 2018. O método de Box-Jenkins foi aplicado para ajustar um modelo de predição SARIMA para incidência geral e por sexo (masculino e feminino) de LV para o período de janeiro de 2019 a dezembro de 2023. Durante o período de 216 meses dessa série temporal, foram registrados 10.431 casos de LV no Maranhão, com uma média de 579 casos por ano. Em relação à faixa etária, houve maior registro no público pediátrico (0 a 14 anos). Houve predominância do sexo masculino, com 6437 casos (61,71%). Os valores do teste de Box-Pierce para incidência geral, sexo masculino e feminino reforçados pelos resultados do teste Ljung-Box sugerem que as autocorrelações de resíduos apresentam um comportamento de ruído branco. Para incidência mensal geral e por sexo masculino e feminino, os modelos SARIMA (2,0,0) (2,0,0), (0,1,1) (0,1,1) e (0,1,1) (2, 0, 0) foram os que mais se ajustaram aos dados, respectivamente. O modelo SARIMA se mostrou uma ferramenta adequada de previsão e análise da tendência de incidência da LV no Maranhão. A determinação da variação temporal e sua predição são determinantes no norteamento de medidas de intervenção em saúde.


Subject(s)
Humains , Mâle , Femelle , Nouveau-né , Nourrisson , Enfant d'âge préscolaire , Enfant , Adolescent , Leishmaniose viscérale/diagnostic , Leishmaniose viscérale/épidémiologie , Saisons , Brésil/épidémiologie , Incidence , Modèles statistiques
5.
Braz. j. biol ; 84: e254095, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355860

ABSTRACT

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.


Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.


Subject(s)
Humains , Animaux , Coléoptères , Écosystème , Saisons , Chili , Biodiversité , Insectes
6.
Braz. j. biol ; 84: e250280, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355867

ABSTRACT

Abstract Endozoochory by waterbirds is particularly relevant to the dispersal of non-flying aquatic invertebrates. This ecological function exercised by birds has been demonstrated in different biogeographical regions, but there are no studies for the neotropical region. In this work, we identified propagules of invertebrates in faeces of 14 syntopic South American waterbird species representing six families, and hatched additional invertebrates from cultured faeces. We tested whether propagule abundance, species richness and composition varied among bird species, and between the cold and warm seasons. We found 164 invertebrate propagules in faecal samples from seven different waterbirds species, including eggs of the Temnocephalida and Notonectidae, statoblasts of bryozoans (Plumatella sp.) and ephippia of Cladocera. Ciliates (including Paramecium sp. and Litostomatea), nematodes and rotifers (Adineta sp. and Nottomatidae) hatched from cultured samples. Potential for endozoochory was confirmed for 12 of 14 waterbird species. Our statistical models suggest that richness and abundance of propagules are associated with bird species and not affected by seasonality. Dispersal by endozoochory is potentially important to a broad variety of invertebrates, being promoted by waterbirds with different ecological and morphological traits, which are likely to drive the dispersal of invertebrates in neotropical wetlands.


Resumo A endozoocoria promovida por aves aquáticas é particularmente relevante para a dispersão de invertebrados aquáticos não-voadores. Essa função ecológica exercida pelas aves tem sido demonstrada para diferentes regiões biogeográficas, porém, não existem estudos para a região neotropical. Neste trabalho nós identificamos propágulos de invertebrados encontrados em fezes de 14 espécies sintópicas de aves aquáticas da América do Sul, representando seis famílias de aves, e também invertebrados emergidos de amostras fecais cultivadas em laboratório. Testamos se a abundância, riqueza de espécies e composição de propágulos de invertebrados variavam entre as espécies de aves e entre estações. Nós encontramos 164 propágulos de invertebrados em amostras fecais de sete espécies de aves, incluindo ovos de Temnocephalida e Notonectidae, estatoblastos de briozoários (Plumatella sp.) e efípios de Cladocera. Ciliados (incluindo Paramecium sp. e Litostomatea), nematóides e rotíferos (Adineta sp. e Nottomatidae) eclodiram de amostras cultivadas. O potencial para endozoocoria foi confirmado para 12 das 14 espécies de aves aquáticas investigadas. Nossos modelos estatísticos sugerem que a riqueza e abundância de propágulos estão associadas às espécies de aves e não são afetadas pela sazonalidade. A dispersão por endozoocoria é importante para uma ampla variedade de invertebrados, sendo promovida por aves aquáticas com diferentes características ecológicas e morfológicas as quais provavelmente regulam a dispersão de invertebrados entre áreas úmidas neotropicais.


Subject(s)
Humains , Animaux , Zones humides , Invertébrés , Saisons , Oiseaux
7.
Braz. j. biol ; 84: e253852, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355905

ABSTRACT

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.


Subject(s)
Animaux , Rivières , Characiformes , Saisons , Lacs , Écosystème , Chaine alimentaire , Poissons , Contenus gastro-intestinaux
8.
Sensors (Basel) ; 23(2)2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36679477

ABSTRACT

Biomass burning (BB) emits a large volume of trace gases and aerosols into the atmosphere, which can significantly affect the earth's radiative balance and climate and has negative impacts on air quality and even human health. In late June 2017, an intense BB case, dominated by forest and savanna fires, occurred in Siberia, and it affected the air quality of Northeast China through long-range transport. Here, multisatellite remote-sensing products and ground-based PM2.5 measurements are used to evaluate the influence of the Siberian smoky plume on Northeast China. The results show that the BB was intense at the early stage when the daily fire count and average fire radiative power exceeded 300 and 200 MW, respectively. The maximum daily fire count reached 1350 in Siberia, and the peak value of instantaneous fire radiative power was as high as 3091.5 MW. High concentrations of CO and aerosols were emitted into the atmosphere by the BB in Siberia. The maximum daily mean values of the CO column concentration and aerosol optical depth (AOD) increased by 3 × 1017 molec·cm2 and 0.5 compared with that during the initial BB stage. In addition, the BB released a large number of absorptive aerosols into the atmosphere, and the UV aerosol index (UVAI) increased by five times at the peak of the event in Siberia. Under the appropriate synoptic conditions and, combined with pyroconvection, the smoky plume was lifted into the upper air and transported to Northeast China, affecting the air quality of Northeast China. The daily mean values of CO concentration, AOD, and UVAI in Northeast China increased by 6 × 1017 molec·cm2, 0.5, and 1.4, respectively, after being affected. Moreover, the concentration of the surface PM2.5 in Northeast China approximately doubled after being affected by the plume. The results of this study indicate that the air quality of Northeast China can be significantly affected by Siberian BBs under favorable conditions.


Subject(s)
Polluants atmosphériques , Pollution de l'air , Incendies , Humains , Polluants atmosphériques/analyse , Biomasse , Surveillance de l'environnement/méthodes , Pollution de l'air/analyse , Chine , Aérosols , Matière particulaire/analyse , Saisons
9.
Sensors (Basel) ; 23(2)2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36679527

ABSTRACT

Small satellites empower different applications for an affordable price. By dealing with a limited capacity for using instruments with high power consumption or high data-rate requirements, small satellite missions usually focus on specific monitoring and observation tasks. Considering that multispectral and hyperspectral sensors generate a significant amount of data subjected to communication channel impairments, bandwidth constraint is an important challenge in data transmission. That issue is addressed mainly by source and channel coding techniques aiming at an effective transmission. This paper targets a significant further bandwidth reduction by proposing an on-the-fly analysis on the satellite to decide which information is effectively useful before coding and transmitting. The images are tiled and classified using a set of detection algorithms after defining the least relevant content for general remote sensing applications. The methodology makes use of the red-band, green-band, blue-band, and near-infrared-band measurements to perform the classification of the content by managing a cloud detection algorithm, a change detection algorithm, and a vessel detection algorithm. Experiments for a set of typical scenarios of summer and winter days in Stockholm, Sweden, were conducted, and the results show that non-important content can be identified and discarded without compromising the predefined useful information for water and dry-land regions. For the evaluated images, only 22.3% of the information would need to be transmitted to the ground station to ensure the acquisition of all the important content, which illustrates the merits of the proposed method. Furthermore, the embedded platform's constraints regarding processing time were analyzed by running the detection algorithms on Unibap's iX10-100 space cloud platform.


Subject(s)
Compression de données , Algorithmes , Saisons , Télémétrie , Suède
10.
Sensors (Basel) ; 23(2)2023 Jan 11.
Article in English | MEDLINE | ID: mdl-36679634

ABSTRACT

Skiing is a popular winter activity spanning various subdisciplines. Key hardware are ski boots, bindings, and skis, which are designed to withstand loads generated during skiing. Obtaining service forces and moments has always been challenging to researchers in the past. The goal of the present study is to develop and test a lightweight and compact measurement system to obtain the Ground Reaction Forces and the kinematics for ski touring and alpine ski. To do so, we adapted two six-axis load cells to fit into ski touring and alpine skis adding 20 mm height and 500 g weight to the original ski. To measure kinematics, we created custom angular sensors from rotary potentiometers. The system was tested indoors using a force platform and motion capture system before a first set of field tests in which the sensors were used to measure ski touring and alpine skis kinetics and kinematics. Validation trials showed maximum errors of 10% for kinetics and 5% for kinematics. Field tests showed data in agreement with previous findings on the topic. The results of this study show the possibility of using our system to study biomechanics and equipment performances for ski touring, alpine skiing, and possibly other disciplines.


Subject(s)
Ski , Phénomènes biomécaniques , Phénomènes biophysiques , Cinétique , Saisons
11.
Sensors (Basel) ; 23(2)2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36679697

ABSTRACT

High-quality measurements of air quality are the highest priority for understanding widespread air pollution. Visibility has been widely suggested to be a good alternative to PM2.5 concentration as a measure. In this study, the similarities and differences between visibility and PM2.5 measurements in China are checked and the results reveal the potential application of visibility observation to the study of air quality. Based on the quality-controlled PM2.5 and visibility data from 2016 to 2018, the nonparametric Spearman correlation coefficient (ρ) values between stations for PM2.5 and visibility-derived surface extinction coefficient (bext) decrease as the station distance (R) increases. Some relatively low ρ values (<0.4) occur in regions characterized by the lowest (background) levels of PM2.5 and bext values, for example, the Tibetan and Yungui Plateau. The relatively lower ρ for bext compared to PM2.5 is probably caused by the predefined maximum threshold of visibility measurements (generally 30 km). A significant correlation between PM2.5 and bext is derived in most stations and relatively larger ρ values are evident in eastern China (Northeast China excluded) and in winter (the national median ρ is 0.67). The abrupt changes in specific mass extinction efficiency (αext) imply a potentially large influence of alternation of visibility sensors or recalibrations on visibility measurements. The bext data are thereafter corrected by comparison to the reference measurements at the adjacent stations, which leads to a three-year quality assured of visibility and bext datasets.


Subject(s)
Polluants atmosphériques , Pollution de l'air , Matière particulaire/analyse , Surveillance de l'environnement/méthodes , Pollution de l'air/analyse , Saisons , Chine , Polluants atmosphériques/analyse
12.
Article in English | MEDLINE | ID: mdl-36674288

ABSTRACT

Heatwaves occur frequently in summer, severely harming the natural environment and human society. While a few long-term spatiotemporal heatwave studies have been conducted in China at the grid scale, their shortcomings involve their discrete distribution and poor spatiotemporal continuity. We used daily data from 691 meteorological stations to obtain torridity index (TI) and heatwave index (HWI) datasets (0.01°) in order to evaluate the spatiotemporal distribution of heatwaves in the Chinese mainland for the period of 1990-2019. The results were as follows: (1) The TI values rose but with fluctuations, with the largest increase occurring in North China in July. The areas with hazard levels of medium and above accounted for 22.16% of the total, mainly in the eastern and southern provinces of China, South Tibet, East and South Xinjiang, and Chongqing. (2) The study areas were divided into four categories according to the spatiotemporal distribution of hazards. The "high hazard and rapidly increasing" and "low hazard and continually increasing" areas accounted for 8.71% and 41.33% of the total, respectively. (3) The "ten furnaces" at the top of the provincial capitals were Zhengzhou, Nanchang, Wuhan, Changsha, Shijiazhuang, Nanjing, Hangzhou, Haikou, Chongqing, and Hefei. While the urbanization level and population aging in the developed areas were further increased, the continuously increasing heatwave hazard should be fully considered.


Subject(s)
Humains , Saisons , Chine/épidémiologie , Villes , Tibet
13.
Physiol Biochem Zool ; 96(1): 62-74, 2023.
Article in English | MEDLINE | ID: mdl-36626839

ABSTRACT

AbstractTorpor is a highly effective response to counter various ecological and physiological bottlenecks in endotherms. In this study, we examined interrelations between thermoregulatory responses and key environmental variables in free-living squirrel gliders (Petaurus norfolcensis) in a habitat with drastic climatic and ecological changes across seasons. To this end, we measured body temperature (Tb) and heart rate (fH) simultaneously throughout the year using implanted data loggers. Squirrel gliders in our study experienced fluctuations in ambient temperature (Ta) between -4.0°C and 44.1°C and expressed torpor at different times during the year. In contrast to our expectations, torpor seemed to be employed flexibly, on demand, and most frequently in spring rather than during the coldest and/or hottest periods. Torpor bouts lasted, on average, about 5 h, and Tb during torpor dropped as low as 17.9°C. The fH during torpor decreased below 50 bpm, which is about one-third of the basal level. The ability to record fH alongside Tb enabled us to also report periods of low fH during thermoconforming hyperthermia at Ta's above 35°C that likely occurred to conserve energy and water. Our findings double the body size of Australian gliders for which data on torpor are available and advance our ecological understanding of the dynamics of torpor expression in wild mammals and of how animals cope with varying conditions. Moreover, they highlight that the flexibility of physiology and thermoregulatory responses are clearly more complex than previously thought.


Subject(s)
Marsupialia , Torpeur , Animaux , Sciuridae , Australie , Torpeur/physiologie , Régulation de la température corporelle/physiologie , Température du corps/physiologie , Saisons , Marsupialia/physiologie , Emploi
14.
BMC Public Health ; 23(1): 102, 2023 Jan 14.
Article in English | MEDLINE | ID: mdl-36641452

ABSTRACT

BACKGROUND: Seasonal agricultural workers working and living in inappropriate sanitary conditions are at great risk for public health. This study aimed to determine the relationships between the sociodemographic variables and life satisfaction of seasonal agricultural workers, and their knowledge, risk perception, and protective behaviors about the COVID-19 pandemic. METHODS: This is a cross-sectional study, that included agricultural workers who are 18 years of age or older and worked seasonally in Yozgat, Turkey, during the period between August 2020 and October 2020. The well-being level was measured using the Personal Wellbeing Index-Adult form (PWIA). The data were collected using the face-to-face survey method and with 739 workers who voluntarily participated in the research. RESULTS: All participants disclosed having insufficient information about Covid-19 and indicated their peers and television as their sources of information. The vast majority of the workers stated that they complied with the mask mandates, social distancing, and hand hygiene. No correlations were found between knowledge, attitudes, and behaviors about Covid-19 and the level of wellbeing. The mean PWIA score of the workers was low (53.7) while they were mostly satisfied with their personal relationships (96.6) and health (76.1). The multivariable linear regression analysis revealed that being male (ß = 0.245) and not having an ongoing health issue (ß = 0.689) were associated with more PWIA; on the other hand, having more children (ß = -0.52) was related to less PWIA. CONCLUSIONS: The well-being level of seasonal workers was lower while it was not associated with knowledge, attitudes, and behaviors about Covid-19.


Subject(s)
, Adulte , Enfant , Humains , Mâle , Adolescent , Femelle , /épidémiologie , /prévention et contrôle , SARS-CoV-2 , Pandémies/prévention et contrôle , Agriculteurs , Études transversales , Turquie/épidémiologie , Saisons , Enquêtes et questionnaires , Satisfaction personnelle
15.
Sci Rep ; 13(1): 769, 2023 Jan 14.
Article in English | MEDLINE | ID: mdl-36641538

ABSTRACT

During winter, the dry, cool air brought by prevailing northeasterly trade winds leads to surface ocean heat loss and convective mixing in the northern Arabian Sea. The current paradigm is that the convective mixing process leads to the injection of nutrients up into the surface waters and exert a dominant control on winter productivity. By combining a variety of observations, atmospheric reanalysis and model simulations, we unraveled the processes responsible for the observed year-to-year chlorophyll-a variations in the northern Arabian Sea. Our findings suggest that the atmospheric high-pressure systems that traverse the northern Arabian Sea every winter and spring disrupt winter convective mixing and create an array of environmental conditions conducive to trigger phytoplankton blooms. The arrival of an atmospheric high with the anticyclonic flow in the northern Arabia Sea sets the stage for a sequence of events culminating in intermittent mixed-layer restratification due to buoyancy gain aided by increased specific humidity, supplemented with abundant sunlight due to clear skies, and suppressed turbulent mixing owing to weak winds. These combined with the mixed layer that is shallower than the euphotic zone and the influx of nutrients into the euphotic zone brought by convective mixing between the calm periods, caused unprecedented high concentrations of chlorophyll-a in the northern Arabian Sea.


Subject(s)
Chlorophylle , Phytoplancton , Chlorophylle/analyse , Chlorophylle A , Saisons , Pression atmosphérique
16.
Med. clín (Ed. impr.) ; 160(2): 60-65, enero 2023. tab
Article in Spanish | IBECS | ID: ibc-JHG-231

ABSTRACT

Antecedentes y objetivo: Es frecuente que los pacientes con fibromialgia refieran que ciertas estaciones del año agravan sus síntomas. Como objetivo primario se determinó la asociación entre síntomas claves de la fibromialgia y estación del año. Como objetivo secundario se determinó la existencia de diferencias en función de los niveles de ansiedad o depresión.Material y métodoMuestra de conveniencia formada por 471 participantes con fibromialgia evaluados antes de iniciar un tratamiento multidisciplinar. Se recogieron datos demográficos y meteorológicos y se evaluaron, mediante instrumentos estandarizados, la intensidad del dolor, la funcionalidad, la fatiga, la rigidez, la calidad del sueño, así como la ansiedad y la depresión.ResultadosLos diferentes grupos estacionales fueron homogéneos en edad, género, nivel educativo, estado marital y situación laboral. No se encontraron diferencias significativas en intensidad del dolor (F=1,334; p=0,265), funcionalidad (F=0,402; p=0,669), fatiga (F=0,714; p=0,490), rigidez (F=0,299; p=0,741), ansiedad (F=0,376; p=0,687), depresión (F=0,608; p=0,545), distrés psicológico (F=0,261; p=0,770), duración del sueño (F=1,507; p=0,223) o el índice de problemas de sueño (F=0,343; p=0,710).ConclusionesNo se han encontrado diferencias en la intensidad de los síntomas de la fibromialgia ni en los porcentajes de gravedad entre las distintas estaciones del año. La ansiedad ha sido más prevalente que la depresión, posiblemente debido a las propias características de la muestra, con mayoría de pacientes con perfil disfuncional. (AU)


Background and objective: Fibromyalgia patients often report that certain seasons aggravate their symptoms. The main objective was to determinate the association between key symptoms of fibromyalgia and the season of the year. A secondary objective was to determinate the existence of differences based on levels of anxiety or depression.Material and methodConvenience sample made up of 471 participants with fibromyalgia evaluated before starting multidisciplinary treatment. Demographic and meteorological data were collected. Clinical data were assessed with standardized instruments of pain intensity, functionality, fatigue, stiffness, sleep quality, anxiety and depression.ResultsThe different groups of participants were homogeneous for age, gender, educational level, marital status and employment situation. No significant differences were found in pain intensity (F=1.334; P=.265), functionality (F=.402; P=.669), fatigue (F=.714; P=.490), stiffness (F=.299; P=.741), anxiety (F=.376; P=.687), depression (F=.608; P=.545), psychological distress (F=.261; P=.770), sleep quantity (F=1.507; P=.223) or sleep disturbances (F=.343; P=.710).ConclusionsNo differences were found in the intensity of fibromyalgia symptoms, nor in the percentages of severity among the different seasons of the year. Anxiety was more prevalent than depression, possibly due to the characteristics of the sample itself, with the majority of patients with a dysfunctional profile. (AU)


Subject(s)
Humains , Fibromyalgie , Saisons , Climat , Dépression , Anxiété
17.
Sensors (Basel) ; 23(1)2023 Jan 02.
Article in English | MEDLINE | ID: mdl-36617083

ABSTRACT

In recent years, the use of remotely sensed and on-ground observations of crop fields, in conjunction with machine learning techniques, has led to highly accurate crop yield estimations. In this work, we propose to further improve the yield prediction task by using Convolutional Neural Networks (CNNs) given their unique ability to exploit the spatial information of small regions of the field. We present a novel CNN architecture called Hyper3DNetReg that takes in a multi-channel input raster and, unlike previous approaches, outputs a two-dimensional raster, where each output pixel represents the predicted yield value of the corresponding input pixel. Our proposed method then generates a yield prediction map by aggregating the overlapping yield prediction patches obtained throughout the field. Our data consist of a set of eight rasterized remotely-sensed features: nitrogen rate applied, precipitation, slope, elevation, topographic position index (TPI), aspect, and two radar backscatter coefficients acquired from the Sentinel-1 satellites. We use data collected during the early stage of the winter wheat growing season (March) to predict yield values during the harvest season (August). We present leave-one-out cross-validation experiments for rain-fed winter wheat over four fields and show that our proposed methodology produces better predictions than five compared methods, including Bayesian multiple linear regression, standard multiple linear regression, random forest, an ensemble of feedforward networks using AdaBoost, a stacked autoencoder, and two other CNN architectures.


Subject(s)
Technologie de télédétection , Triticum , Saisons , Théorème de Bayes ,
18.
Sensors (Basel) ; 23(1)2023 Jan 02.
Article in English | MEDLINE | ID: mdl-36617102

ABSTRACT

Magnetic Barkhausen noise (MBN), sensitive to the microstructure of materials, can be applied in the surface decarburization depth detection of ferromagnetic specimens. However, the effects of core microstructures on the determination results of decarburization depth have not been explored. In this study, MBN was employed to evaluate the magnetic properties of the decarburized 60Si2Mn spring steels with martensitic and pearlitic core microstructures. Spring steel samples were austenitized at different times to generate different decarburization depths. Seven magnetic features were extracted from the MBN butterfly profiles. We used the variation coefficient, linear correlation coefficient, and normalized sensitivity to discuss the influence of the core microstructures on these seven features. The different core microstructures led to a large difference in the ability of MBN features to characterize the decarburization layer depth. However, three features of MBN butterfly profiles demonstrated an approximately linear dependency (linear correlation coefficient > 94%) on surface decarburization depth and monotonically increased with the increase in depth in both core microstructures of spring steels.


Subject(s)
Aimants , Acier , Phénomènes physiques , Saisons , Phénomènes magnétiques
19.
PeerJ ; 11: e14511, 2023.
Article in English | MEDLINE | ID: mdl-36620745

ABSTRACT

Background: Integrative studies of animals and associated microbial assemblages (i.e., the holobiont) are rapidly changing our perspectives on organismal ecology and evolution. Insular vertebrates provide ideal natural systems to understand patterns of host-gut microbiota coevolution, the resilience and plasticity these microbial communities over temporal and spatial scales, and ultimately their role in the host ecological adaptation. Methods: Here we used the endemic Balearic wall lizard Podarcis lilfordi to dissect the drivers of the microbial diversity within and across host allopatric populations/islets. By focusing on three extensively studied populations/islets of Mallorca (Spain) and fecal sampling from individually identified lizards along two years (both in spring and autumn), we sorted out the effect of islet, sex, life stage, year and season on the microbiota composition. We further related microbiota diversity to host genetics, trophic ecology and expected annual metabolic changes. Results: All the three populations showed a remarkable conservation of the major microbial taxonomic profile, while carrying their unique microbial signature at finer level of taxonomic resolution (Amplicon Sequence Variants (ASVs)). Microbiota distances across populations were compatible with both host genetics (based on microsatellites) and trophic niche distances (based on stable isotopes and fecal content). Within populations, a large proportion of ASVs (30-50%) were recurrently found along the four sampling dates. The microbial diversity was strongly marked by seasonality, with no sex effect and a marginal life stage and annual effect. The microbiota showed seasonal fluctuations along the two sampled years, primarily due to changes in the relative abundances of fermentative bacteria (mostly families Lachnospiraceae and Ruminococcaceae), without any major compositional turnover. Conclusions: These results support a large resilience of the major compositional aspects of the P. lilfordi gut microbiota over the short-term evolutionary divergence of their host allopatric populations (<10,000 years), but also indicate an undergoing process of parallel diversification of the both host and associated gut microbes. Predictable seasonal dynamics in microbiota diversity suggests a role of microbiota plasticity in the lizards' metabolic adaptation to their resource-constrained insular environments. Overall, our study supports the need for longitudinal and integrative studies of host and associated microbes in natural systems.


Subject(s)
Microbiome gastro-intestinal , Lézards , Microbiote , Animaux , Microbiome gastro-intestinal/génétique , Saisons , Fèces , Lézards/microbiologie
20.
Proc Biol Sci ; 290(1991): 20222262, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36651053

ABSTRACT

Climate change increases the frequency and intensifies the magnitude and duration of extreme events in the sea, particularly so in coastal habitats. However, the interplay of multiple extremes and the consequences for species and ecosystems remain unknown. We experimentally tested the impacts of summer heatwaves of differing intensities and durations, and a subsequent upwelling event on a temperate keystone predator, the starfish Asterias rubens. We recorded mussel consumption throughout the experiment and assessed activity and growth at strategically chosen time points. The upwelling event overall impaired starfish feeding and activity, likely driven by the acidification and low oxygen concentrations in the upwelled seawater. Prior exposure to a present-day heatwave (+5°C above climatology) alleviated upwelling-induced stress, indicating cross-stress tolerance. Heatwaves of present-day intensity decreased starfish feeding and growth. While the imposed heatwaves of limited duration (9 days) caused slight impacts but allowed for recovery, the prolonged (13 days) heatwave impaired overall growth. Projected future heatwaves (+8°C above climatology) caused 100% mortality of starfish. Our findings indicate a positive ecological memory imposed by successive stress events. Yet, starfish populations may still suffer extensive mortality during intensified end-of-century heatwave conditions.


Subject(s)
Changement climatique , Écosystème , Animaux , Eau de mer , Étoile de mer , Saisons , Composés de benzalkonium
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