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The ongoing and projected retreat of Arctic sea ice has garnered international interest toward the utilization of Arctic maritime corridors for shipping, tourism, and development. Yet, with potential for increasing traffic in Arctic regions, it's important to consider additional environmental variables affected by climate change which may threaten maritime operations. Here, we use four climate model projections to produce ocean wave simulations and investigate the future magnitude and seasonality of sea ice risk coupled with wave hazards. Analyzing the potential 5 mo shipping season spanning July to November along the Northwest Passage maritime route between 2020 and 2070, our results show a substantial decline in sea ice risk over the analysis time period, resulting in near open-water conditions along the route for a 5 mo period by 2070. However, as seasonal ice coverage retreats, there is a significant upward trend in wave heights along the route during July and November, with the timing of the greatest wave height shifting away from September toward later in the season. This result is pertinent as the possibility of seasonally unprecedented extreme waves coupled with subfreezing late fall temperatures makes for an especially hazardous environment, thus emphasizing the importance of considering the interaction between evolving sea ice and interdependent hazards when predicting the risks and challenges faced by Arctic maritime operations.
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Robotic milking systems are successful innovations in the development of dairy cattle. The objective of this study was to analyse the milking characteristics and behavior of dairy cows of different calving orders in "milk first" robotic milking systems. The data were collected from a commercial herd located in the Midwest region of Minas Gerais (Brazil), which uses an automatic milking system (AMS TM, DeLaval). Were analysed 26,574 observations of 235 Holstein cows were available. Data were evaluated by multivariate analysis of variance and the Tukey test. - Tthe characteristics milk flow and milking efficiency were more favourable for multiparous cows (p <0.01), while the time in the stall was more favourable for primiparous females (p <0.01). The values of handling time were better in the primiparous cows (p <0.01). Primiparous cows had higher amounts of kick-off (p <0.001), and multiparous cows had higher incomplete milkings (p <0.001). The number of incomplete milkings showed a higher ratio in terms of reduction in milk production in 26.6% in primiparous cows and 26.7% in multiparous cows (p <0.01). Regarding the behavioral characteristics, primiparous cows had higher amounts of kickbacks, while multiparous cows had greater quantities of incomplete milkings.
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Comportamento Animal , Indústria de Laticínios , Lactação , Paridade , Robótica , Animais , Bovinos/fisiologia , Feminino , Paridade/fisiologia , Lactação/fisiologia , Indústria de Laticínios/métodos , Comportamento Animal/fisiologia , Gravidez , Leite/química , BrasilRESUMO
A persistent challenge in tasks involving large-scale dynamical systems, such as state estimation and error reduction, revolves around processing the collected measurements. Frequently, these data suffer from the curse of dimensionality, leading to increased computational demands in data processing methodologies. Recent scholarly investigations have underscored the utility of delineating collective states and dynamics via moment-based representations. These representations serve as a form of sufficient statistics for encapsulating collective characteristics, while simultaneously permitting the retrieval of individual data points. In this paper, we reshape the Kalman filter methodology, aiming its application in the moment domain of an ensemble system and developing the basis for moment ensemble noise filtering. The moment system is defined with respect to the normalized Legendre polynomials, and it is shown that its orthogonal basis structure introduces unique benefits for the application of Kalman filter for both i.i.d. and universal Gaussian disturbances. The proposed method thrives from the reduction in problem dimension, which is unbounded within the state-space representation, and can achieve significantly smaller values when converted to the truncated moment-space. Furthermore, the robustness of moment data toward outliers and localized inaccuracies is an additional positive aspect of this approach. The methodology is applied for an ensemble of harmonic oscillators and units following aircraft dynamics, with results showcasing a reduction in both cumulative absolute error and covariance with reduced calculation cost due to the realization of operations within the moment framework conceived.
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The age and daily growth of fish are registered through the deposition of increments in their otoliths, which are concretions formed by the precipitation of substances present in the endolymphatic fluid, mainly calcium carbonate (CaCO3). Faced with the need to fill some of the gaps in the knowledge on the occurrence and duration of the initial stages of snapper species' life cycles in the Abrolhos Bank, this study aimed to describe the growth rates, age, and period of pelagic larval duration (PLD) of three snapper species during the larval pre-settlement phase, in the Abrolhos Bank region. The post-larvae were captured using light traps. Otoliths were removed from 117 samples of snapper species; however, only 69 were viable for age estimation, of which 15 were Lutjanus analis, 25 were Lutjanus jocu, and 29 were Lutjanus synagris. Together, the samples presented individuals with total lengths ranging from 16.14 to 24.76 mm and ages from 21 to 39 days. Settlement marks were found for all three species, and the average PLD was ~25 days. The somatic growth of the snapper species was positively correlated with otolith growth. L. jocu presented the greatest daily growth compared to the other species. The three species use the Abrolhos Bank as a larval settlement site, demonstrating plasticity by using different habitats throughout their lives.
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Larva , Membrana dos Otólitos , Animais , Larva/crescimento & desenvolvimento , Membrana dos Otólitos/crescimento & desenvolvimento , Membrana dos Otólitos/química , Perciformes/crescimento & desenvolvimento , Parques Recreativos , Percas/crescimento & desenvolvimento , Percas/fisiologiaRESUMO
Salt marshes act as natural barriers that reduce wave energy during storm events and help protect coastal communities located in low-lying areas. This ecosystem can be an important asset for climate adaptation due to its particular capability of vertically accrete to adjust to long-term changes in water levels. Therefore, understanding marsh protection benefits thresholds in the face of sea-level rise (SLR) is important for planning future climate adaptation. In this context, the main goal of this manuscript is to examine how the storm protection benefits provided by salt marshes might evolve under SLR projections with different probability levels and emission pathways. In this study, a modeling framework that employs marsh migration predictions from the Sea Level Affecting Marshes Model (SLAMM) as parameterization into a hydrodynamic and wave model (ADCIRC + SWAN) was utilized to explicitly represent wave attenuation by vegetation under storm surge conditions. SLAMM predictions indicate that the SLR scenario, a combination of probability level and emission pathways, plays a substantial role in determining future marsh migration or marsh area loss. For example, results based on the 50% probability, stabilized emissions scenario show an increase of 45% in the marsh area on Maryland's Lower Eastern Shore by 2100, whereas Dorchester County alone could experience a 75% reduction in total salt marsh areas by 2100 under the 1% probability, growing emissions scenario. ADCIRC + SWAN results using SLAMM land cover and elevation outputs indicate that distinct temporal thresholds emerge where marsh extent sharply decreases and wave heights increase, especially after 2050, and exacerbates further after 2080. These findings can be utilized for guiding environmental policies and to aid informed decisions and actions in response to SLR-driven environmental changes.
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Mudança Climática , Monitoramento Ambiental , Elevação do Nível do Mar , Áreas Alagadas , Conservação dos Recursos Naturais , Maryland , Modelos TeóricosRESUMO
To date, much effort has been devoted toward the study of protein corona formation onto large gold nanoparticles (GNPs). However, the protein corona concept breaks down for GNPs in the ultrasmall size regime (<3 nm), and, as a result, our understanding of ultrasmall GNP (usGNP)-protein interactions remains incomplete. Herein, we used anionic usGNPs and six different proteins as model systems to systematically investigate usGNP-protein interactions, with particular focus on the time evolution and long-term behavior of complex formation. The different proteins comprised chymotrypsin (Cht), trypsin (Try), thrombin (Thr), serum albumin (HSA), cytochrome c (Cyt c), and factor XII (FXII). We used a range of biochemical and biophysical methods to estimate binding affinities, determine the effects of usGNPs on protein structure and function, assess the reversibility of any protein structural and functional changes, and evaluate usGNP-protein complex stability. Among the main findings, we observed that prolonged (24 h)âbut not short-term (10 min)âinteractions between proteins and usGNPs permanently altered protein function, including enzyme activities (Try, Thr, and FXIIa), peroxidase-like activity (Cyt c), and ligand-binding properties (HSA). Remarkably, this occurred without any large-scale loss of the native global conformation, implying time-dependent effects of usGNPs on local protein conformation or dynamics. We also found that both short-(10 min) and long-term (24 h) interactions between proteins and usGNPs yielded short-lived complexes, i.e., there was no time-dependent "hardening" of the interactions at the binding interface as usually seen with large GNPs. The present study increases our fundamental understanding of nano-bio interactions in the ultrasmall size regime, which may assist the safe and effective translation of usGNPs into the clinic.
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Nanopartículas Metálicas , Coroa de Proteína , Ouro/química , Nanopartículas Metálicas/química , Coroa de Proteína/química , Albumina Sérica , Conformação ProteicaRESUMO
Mining activities generate large quantities of wastes that significantly alter the biogeochemistry and ecological structure of entire river basins. Microbial communities that develop in these areas present a variety of survival and adaptation mechanisms. Knowing this diversity at the molecular level is strategic both for understanding adaptive processes and for identifying genomes with potential use in bioremediation and bioprospecting. In this work, prokaryotic and eukaryotic communities were evaluated by meta-taxonomics (16S and 18S amplicons) in sediments and water bodies impacted by acid mine drainage in an important coal mining area in southern Brazil. Five sampling stations were defined on a gradient of impacts (pH 2.7-4.25). Taxon diversity was directly proportional to pH, being greater in sediments than in water. The dominant prokaryotic phyla in the samples were Proteobacteria, Actinobacteria, Acidobacteria, OD1, Nitrospirae, and Euryarchaeota, and among the eukaryotes, algae (Ochrophyta, Chlorophyta, Cryptophyceae), fungi (Basidiomycota, Ascomycota, and Cryptomycota), and protists (Ciliophora, Heterolobosea, Cercozoa). The prokaryotic genera Leptospirillum, Acidithiobacillus, Acidiphilium, Thiomonas, Thermogymnomonas, and Acidobacterium, and the eukaryotic genera Pterocystis and Poteriospumella were associated with more acidic conditions and higher metal concentrations, while the prokaryotic genera Sediminibacterium, Gallionella Geothrix, and Geobacter were more abundant in transitional environments.
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Bactérias , Microbiota , Brasil , Bactérias/genética , Rios/microbiologia , Fungos , ÁguaRESUMO
Impairments in several domains of cognitive functions are observed in people with Type 2 Diabetes Mellitus (T2DM), often accompanied by low Brain-derived neurotrophic factor (BDNF) concentrations. Although aerobic and resistance exercise enhances cognitive functions and raises BDNF concentrations in several populations, it remained uncertain in T2DM subjects. This study compared the effects of a single bout of aerobic (AER, 40 min of treadmill walk at 90-95% of the maximum walk speed) or resistance (RES, 3 × 10 repetitions in eight exercises at 70% of 10-RM) exercise on specific cognitive domain performance and plasma BDNF concentrations of physically active T2DM subjects. Eleven T2DM subjects (9 women/2 men; 63 ± 7 years) performed two counterbalanced trials on non-consecutive days. Stroop Color and Word (SCW) task [assessing the attention (congruent condition) and inhibitory control (incongruent condition)], Visual response time (assessing the response time), and blood collection (for plasma BDNF concentrations) were performed pre and post-exercise sessions. With distinct magnitude, both AER and RES improved the incongruent-SCW (d = - 0.26 vs. - 0.43 in AER and RES, respectively; p < 0.05), RT(best) (d = - 0.31 vs. - 0.52, p < 0.05), and RT(1-5) (d = - 0.64 vs. - 0.21, p < 0.05). The congruent-SCW and RT(6-10) were not statistically different. Plasma BDNF concentrations were elevated 11% in AER (d = 0.30) but decreased by 15% in RES (d = - 0.43). A single session of aerobic or resistance exercise similarly improved the inhibitory control and response time of physically active T2DM subjects. Nevertheless, aerobic and resistance exercise sessions induced an opposite clinical effect in plasma BDNF concentrations.
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Diabetes Mellitus Tipo 2 , Treinamento Resistido , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Diabetes Mellitus Tipo 2/terapia , Fator Neurotrófico Derivado do Encéfalo , Tempo de Reação , Exercício Físico/fisiologiaRESUMO
INTRODUCTION AND OBJECTIVES: Primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH) and PBC overlap syndrome (AIH/PBC) have been associated with a higher risk of hepatocellular carcinoma (HCC) and extra-hepatic malignancy (EHM). This study aims to assess potential risk factors associated with cancer development in PBC and AIH/PBC. MATERIALS AND METHODS: The Brazilian Cholestasis Study Group database was reviewed to compare clinical and laboratory features of PBC patients with HCC and EHM with those without cancer. RESULTS: Among the 752 PBC patients enrolled, 64 of them with AIH/PBC, 87 cancers were identified in 72 patients, including 20 cases of HCC and 67 of EHM. Patients with HCC had a higher prevalence of cirrhosis (95% vs. 32.5% of those subjects without cancer, p≤0.001), smoking (55% vs. 12.3%, p≤0.001), CREST syndrome (30% vs 7.6%, p=0.003) and prior azathioprine (30% vs 8%, p= 0.005) and prednisone (35% vs 14%, p= 0.018) use, whereas patients with EHM had a higher prevalence of smoking (42.3% vs 12.4% of those subjects without cancer, p= <0.001), AMA positivity (96.6% vs 80.1%, p≤0.001), azathioprine therapy (21% vs 7.9%, p= 0.01) and concurrent other autoimmune diseases. In multivariate analysis, cirrhosis, obesity and prior azathioprine therapy were independent risk factors for HCC, while Sjogren syndrome and psoriasis were associated with EHM. Fibrates reduced EHM risk. CONCLUSIONS: The prevalence of EHM is higher when compared to HCC in PBC patients. Cirrhosis, obesity, prior azathioprine use, and concurrent autoimmune diseases were significantly associated with cancer in PBC.
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Carcinoma Hepatocelular , Hepatite Autoimune , Cirrose Hepática Biliar , Neoplasias Hepáticas , Humanos , Hepatite Autoimune/complicações , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/epidemiologia , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/epidemiologia , Cirrose Hepática Biliar/complicações , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/complicações , Azatioprina/uso terapêutico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/complicações , Cirrose Hepática/complicações , Fatores de Risco , Síndrome , Obesidade/complicaçõesRESUMO
Coastal communities are vulnerable to wave and storm surges during extreme events, highlighting the need to increase community resilience. The effectiveness of natural wetlands in attenuating waves is vital to designing strategies for protecting public safety. This study aimed to understand how vegetation attenuates waves and determine the best method for modeling vegetation's impact on wave dynamics. The researchers compared two different vegetation representations in numerical models, implicit and explicit, using SWAN and XBeach at varying spatial resolutions. The study focused on two marshes in the Chesapeake Bay, using field measurements to investigate the accuracy of each method in representing wave attenuation by vegetation and the implications of explicitly representing average characteristics of one vegetation species on a regional level. Results showed that explicit modeling using average vegetation characteristics provided more accurate results than the implicit model, which only showed wave attenuation due to topography. The finer scale resolution and site-specific vegetation characteristics further improved the accuracy of wave attenuation observed. Understanding the trade-offs between different vegetation representations in numerical models is essential to accurately represent wave attenuation and design effective protection strategies for coastal communities.
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Baías , Monitoramento Ambiental , Áreas AlagadasRESUMO
Sea level rise (SLR) is the most significant climate change-related threat to coastal wetlands, driving major transformations in coastal regions through marsh migration. Landscape transformations due to marsh migration are manifested in terms of horizontal and vertical changes in land cover and elevation, respectively. These processes will have an impact on saltmarsh wave attenuation that is yet to be explored. This study stands as a comprehensive analysis of spatially distributed wave attenuation by vegetation in the context of a changing climate. Our results show that: i) changes in saltmarsh cover have little to no effect on the attenuation of floods, while ii) changes in elevation can significantly reduce flood extents and water depths; iii) overland wave heights are directly influenced by marsh migration, although iv) being indirectly attenuated by the water depth limiting effects of water depth attenuation driven by changes in elevation; v) the influence of saltmarsh accretion on wave attenuation is largely evident near the marsh edge, where the increasing elevations can drive major wave energy losses via wave breaking. Lastly, vi) considering the synergy between SLR, marsh migration, and changes in elevation results in significantly more wave attenuation than considering the eustatic effects of SLR and/or horizontal marsh migration alone, and therefore should be adopted in future studies.
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Elevação do Nível do Mar , Áreas Alagadas , Monitoramento Ambiental , Mudança Climática , Água , EcossistemaRESUMO
Type 2 diabetes mellitus (T2DM) is an important chronic disease around the world, and according to the World Health Organization, it is the 9th principal cause of global death. This pathology is characterized by high levels of circulating glucose as a result of insulin resistance, and it is well stated that inflammation related to obesity is directly associated with the development of the disease. The purinergic signalling is involved in both pancreatic destruction, which impairs insulin secretion, and the cytokine production that favors insulin resistance in T2DM. In this review, the purinergic signalling aspects will be discussed, showing the impact of the enzymes, nucleotides, nucleosides, and receptors of this system and the cytokines that result in inflammation, in the development and progression of T2DM, besides, pointing the purinergic receptors as a possible therapeutic approach.
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Diabetes Mellitus Tipo 2 , Resistência à Insulina , Diabetes Mellitus Tipo 2/patologia , Humanos , Inflamação/patologia , Obesidade/patologia , Transdução de SinaisRESUMO
Three SAR-derived observations of dark surface patches along the Northeastern Brazilian coastline by the end of 2019 were misreported in the Brazilian media as oil spill-related. Unfortunately, these observations were misled by false positives or look-alikes. Therefore, this paper aims to technically evaluate these look-alike classes by analyzing image attributes found to be helpful to the identification of ocean targets, including oil spills, rain cells, biofilms, and low wind conditions. We use image augmentation to extend our dataset size and create the probability density function curves. The processing includes image segmentation, optimal attribute extraction, and classification with random forest classifiers. Our results contrast with the open-source oil spill detection system and patch classifier methodology called "RIOSS." Analysis of the feature probability density functions based on optimal attributes is promising since we could capture most of the false positive targets in the three SAR-reported images in 2019. The only exception was the biofilm slick observed on October 28th, where the RIOSS mistakenly classified this organic patch as a low wind region with oil spots. This pitfall is acceptable at this project stage since we had only five biogenic film samples to train the algorithm.
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Poluição por Petróleo , Poluentes Químicos da Água , Brasil , Monitoramento Ambiental/métodos , Poluição por Petróleo/análise , Radar , Poluentes Químicos da Água/análise , VentoRESUMO
ABSTRACT: Campos, BT, Penna, EM, Rodrigues, JGS, Mendes, TT, Maia-Lima, A, Nakamura, FY, Vieira, ÉLM, Wanner, SP, and Prado, LS. Influence of mental fatigue on physical performance, and physiological and perceptual responses of judokas submitted to the Special Judo Fitness Test. J Strength Cond Res 36(2): 461-468, 2022-Mentally fatigued athletes present impaired aerobic performance, strength endurance, and manual dexterity, despite no changes in anaerobic performance and maximal muscle strength and power. Noteworthy, the effect of mental fatigue on physical performance during high-intensity intermittent tests that require specific motor skills of fighting sports has not been investigated. Therefore, this study aimed to verify whether mental fatigue influences performance and physiological and perceptual responses of judokas subjected to a high-intensity intermittent test designed specifically and validated for judo. Each judoka performed 2 experimental trials-a control trial one and the other one after the induction of mental fatigue. These trials were scheduled in a random and balanced order. In both trials, lactate, glucose, and cortisol concentrations, the heart rate variability, and perceptual variables were collected after the initial treatment and after the Special Judo Fitness Test (SJFT). The initial treatment consisted of a 30-minute cognitive demanding task (Stroop Color test) or watching a movie (control) and was followed by the SJFT. The Stroop Color test increased the perceptions of mental fatigue and effort, without affecting motivation for subsequent testing. Unexpectedly, mentally fatigued athletes did not show reduced performance during the SJFT. Regarding the physiological variables, no significant differences were identified between the 2 experimental conditions. We conclude that physical performance measured during a specific test for judokas is not impaired by a previous 30-minute cognitive task that causes mental fatigue. In addition, this cognitive task did not influence the physiological changes induced by the specific physical test.
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Desempenho Atlético , Artes Marciais , Teste de Esforço , Humanos , Fadiga Mental , Aptidão Física , Desempenho Físico FuncionalRESUMO
BACKGROUND: The present study investigated the sensory acceptance, oxidative damage and protection, and possible anatomical-structural damage of cells from the surface of shapes of minimally processed yam. The tubers were minimally processed into the peeled rondelle, dice and 'chateau cut' (chateau) shapes, the latter of which was obtained after performing the abrasion technique. Control treatment corresponded to the rondelle shape with the periderm. The pieces were kept packed at 5 ± 2 °C for 14 days. RESULTS: Peeled rondelle and chateau were sensorially the most well-accepted yam shapes and achieved the highest purchase intention. The enzymes were partially modulated by the detected H2 O2 levels. Oxidative burst lasted longer in the minimally processed tissues than in the control. Polyphenol oxidase activity showed a clear difference in behavior between the minimally processed pieces and the control. Minimal processing induced transient increases in phenolic compounds, for which the expression was lowest in the abraded pieces. On the other hand, these pieces exhibited greater cell collapse on the surface of the amyliferous parenchyma. CONCLUSION: Based on the results of the trained panel, the abrasion technique is an alternative to provide shapes that are better accepted and marketable, more resistant to browning, and can be stored for up to 12 days. Resistance to browning may be related to a more efficient modulation of enzymatic antioxidant systems and intense deposition of cell debris on the surface of the amyliferous parenchyma. © 2021 Society of Chemical Industry.
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Comportamento do Consumidor , Dioscorea/química , Manipulação de Alimentos/métodos , Catecol Oxidase/análise , Catecol Oxidase/metabolismo , Dioscorea/metabolismo , Manipulação de Alimentos/instrumentação , Humanos , Fenóis/análise , Fenóis/metabolismo , Tubérculos/química , Tubérculos/metabolismoRESUMO
Ethylene regulates different aspects of the plant's life cycle, such as flowering, and acts as a defense signal in response to environmental stresses. Changes induced by water deficit (WD) in gene expression of the main enzymes involved in ethylene biosynthesis, 1-aminocyclopropane-1-carboxylic acid synthase (ACS) and oxidase (ACO), are frequently reported in plants. In this study, coffee (Coffea arabica) ACS and ACO family genes were characterized and their expression profiles were analyzed in leaves, roots, flower buds, and open flowers from plants under well-watered (WW) and water deficit (WD) conditions. Three new ACS genes were identified. Water deficit did not affect ACS expression in roots, however soil drying strongly downregulated ACO expression, indicating a transcriptional constraint in the biosynthesis pathway during the drought that can suppress ethylene production in roots. In floral buds, ACO expression is water-independent, suggesting a higher mechanism of control in reproductive organs during the final flowering stages. Leaves may be the main sites for ethylene precursor (1-aminocyclopropane-1-carboxylic acid, ACC) production in the shoot under well-watered conditions, contributing to an increase in the ethylene levels required for anthesis. Given these results, we suggest a possible regulatory mechanism for the ethylene biosynthesis pathway associated with coffee flowering with gene regulation in leaves being a key point in ethylene production and ACO genes play a major regulatory role in roots and the shoots. This mechanism may constitute a regulatory model for flowering in other woody species. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01235-y.
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This study aimed to evaluate the effect of head pre-cooling on the 5-km time-trial performance of amateur runners in the heat. In a counterbalanced design, 15 male amateur runners (22.6 ± 3.5 y; VO2 max in heat 42.3 ± 4.4 mLO2 /kg/min) completed two 5-km time trials performed in the heat (35°C, 50% relative humidity). In one trial (HCOOL), participants underwent 20 min of head cooling in a temperate environment (23°C, 70% relative humidity) prior to exercise. In another trial (CON), exercise was preceded by 20 min of rest under the same temperature conditions. Exercise time was shorter in HCOOL (25 min and 36 s ± 3 min) compared to CON (27 ± 3 min; p = 0.02). Rectal temperature was reduced during the pre-exercise intervention in HCOOL (p < 0.001), but not in CON (p = 0.55). Relative changes in rectal temperature and mean head temperature were lower throughout HCOOL when compared with CON condition (p = 0.005 and p = 0.022, respectively). Mean skin temperature, heart rate, and rating of perceived exertion did not differ between HCOOL and CON conditions throughout exercise (p = 0.20, p = 0.52 and 0.31, respectively). Thermal comfort was lower in HCOOL condition in pre-exercise (p = 0.014) with no differences observed throughout exercise (p = 0.61). 5-km running performance in a hot environment was improved after a 20-min head cooling intervention, suggesting that this method may be practical as pre-cooling strategy and easily administered to both professional and amateur runners alike.
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Desempenho Atlético/fisiologia , Cabeça/fisiologia , Temperatura Alta , Hipotermia Induzida/métodos , Corrida/fisiologia , Aclimatação/fisiologia , Temperatura Corporal/fisiologia , Temperatura Baixa , Água Potável/administração & dosagem , Frequência Cardíaca , Humanos , Umidade , Masculino , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Reto/fisiologia , Temperatura Cutânea/fisiologia , Sudorese/fisiologia , Fatores de Tempo , Adulto JovemRESUMO
ABSTRACT: Ramos, GP, Nakamura, FY, Penna, EM, Mendes, TT, Mahseredjian, F, Lima, AM, Garcia, ES, Prado, LS, and Coimbra, CC. Comparison of physical fitness and anthropometrical profiles among Brazilian female soccer national teams from U15 to senior categories. J Strength Cond Res 35(8): 2302-2308, 2021-This study aimed to compare anthropometric and physical fitness of Brazilian female national team soccer players from the U15 to senior categories, and to compare the physical performance between selected and nonselected players. Subjects included 231 athletes (U15, n = 46, U17, n = 49, U20, n = 98, and Senior, n = 38). Body mass, height, sum of skinfolds, squat jump (SJ), countermovement jump (CMJ), 20-m linear sprint, and Yo-Yo IR1 were assessed. The U15 players were shorter than all other groups (p < 0.01) and lighter than U20 players (p < 0.01). Regarding physical tests, Senior athletes presented higher SJ compared with U20, and both showed higher CMJ and SJ compared with the U15 and U17 (p < 0.05). Senior athletes were also faster than players of all other categories in 20-m sprint (p < 0.01) and covered the greatest distance in the Yo-Yo IR1 (p < 0.05). U20 were better in the Yo-Yo IR1 than the younger groups (p < 0.05). When comparing selected and nonselected players, no differences were identified in anthropometric measures (p > 0.05). However, selected players from U17, U20, and Senior teams showed better performance in Yo-Yo IR1 than nonselected ones (p < 0.05). Finally, selected senior athletes also presented higher CMJ and SJ than nonselected players (p < 0.05). These results suggest that, although there is a tendency for maintenance in anthropometric measures from the age of 15 years, there are substantial improvements in speed, lower-body power, and aerobic capacity from U20 age group. In addition, it seems that intermittent aerobic fitness contributes to the selection of players to international tournaments in national teams.
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Desempenho Atlético , Futebol , Adolescente , Antropometria , Atletas , Feminino , Humanos , Aptidão FísicaRESUMO
Deciduous and evergreen trees are usually considered the main coexisting functional groups in seasonally dry tropical forests (SDTF). We compared leaf and stem traits of 22 woody species in the Brazilian Caatinga to investigate whether deciduous (DC) and evergreen (EV) species have divergent water-use strategies. Our hypothesis was that DC trees compensate for their short leaf longevity by being less conservative in water use and showing higher variation in the seasonal water potential after leaf shedding. Evergreen species should exhibit a highly conservative water use strategy, which reduces variations in seasonal water potential and the negative effects of desiccation. Our leaf dynamics results indicate that the crown area of DC trees is more sensitive to air and soil drought, whereas EV trees are only sensitive to soil drought. Deciduous species exhibit differences in a set of leaf traits confirming their acquisitive strategy, which contrasts with evergreen species. However, when stomatal traits are considered, we found that DC and EV have similar stomatal regulation strategies (partially isohydric). We also found divergent physiological strategies within DC. For high wood density DC, the xylem water potential (Ψxylem) continued to drop during the dry season. We also found a negative linear relationship between leaf life span (LL) and the transpiration rate per unit of hydraulic conductivity (Λ), indicating that species with high LL are less vulnerable to hydraulic conductivity loss than early-deciduous species. Collectively, our results indicate divergence in the physiology of deciduous species, which suggests that categorizing species based solely on their leaf phenology may be an oversimplification.
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Secas , Clima Tropical , Brasil , Florestas , Folhas de Planta , Árvores , Água , MadeiraRESUMO
Here we investigated the diversity of bacterial communities from deep-sea surface sediments under influence of asphalt seeps at the Sao Paulo Plateau using next-generation sequencing method. Sampling was performed at North São Paulo Plateau using the human occupied vehicle Shinkai 6500 and her support vessel Yokosuka. The microbial diversity was studied at two surficial sediment layers (0-1 and 1-4 cm) of five samples collected in cores in water depths ranging from 2456 to 2728 m. Bacterial communities were studied through sequencing of 16S rRNA gene on the Ion Torrent platform and clustered in operational taxonomic units. We observed high diversity of bacterial sediment communities as previously described by other studies. When we considered community composition, the most abundant classes were Alphaproteobacteria (27.7%), Acidimicrobiia (20%), Gammaproteobacteria (11.3%) and Deltaproteobacteria (6.6%). Most abundant OTUs at family level were from two uncultured bacteria from Actinomarinales (5.95%) and Kiloniellaceae (3.17%). The unexpected high abundance of Alphaproteobacteria and Acidimicrobiia in our deep-sea microbial communities may be related to the presence of asphalt seep at North São Paulo Plateau, since these bacterial classes contain bacteria that possess the capability of metabolizing hydrocarbon compounds.