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1.
J Vis ; 23(8): 16, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610734

RESUMO

Coincidence anticipation (CA) refers to the ability to coordinate responses to the arrival of a moving object. This study investigates the neurobehavioral processes that underlie CA through the measurement of electroencephalography (EEG) recorded during a CA task on a 17-foot plastic rail with evenly spaced LED lights. Participants responded at the anticipated moment a sequence of successively lit LEDs coincided with a stationary target. Healthy young adult participants (Mage = 21) performed six blocks with movement at 20, 30, or 40 mph and the direction either inbound or outbound relative to the participant. Behavioral results demonstrated a main effect of speed and an interaction between speed and direction, with outbound motion producing early responses and inbound motion producing delayed responses that increased at greater speeds. EEG demonstrated characteristic P1, N2, and P3-like visual evoked potentials (VEPs). VEP amplitudes revealed a significant direction by channel interaction for the P1, indicative of more medial responses for inbound motion. Significant laterality differences were present in the N2, whereas the P3 component produced significant main effects and interactions of speed and direction. This novel combination of three-dimensional CA with EEG demonstrates systematic brain responses that are tuned for motion speed and sensitive to different egocentric motion patterns thereby shedding new light on the mechanism of human visual-motor control.


Assuntos
Encéfalo , Potenciais Evocados Visuais , Adulto Jovem , Humanos , Eletroencefalografia , Lateralidade Funcional , Voluntários Saudáveis
2.
Environ Microbiol ; 24(12): 6184-6199, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35799501

RESUMO

Soil microbial community composition routinely correlates with pH, reflecting both direct pH effects on microbial physiology and long-term biogeochemical feedbacks. We used two watershed-scale liming experiments to identify short- (2 years) and long-term (25 years) changes in the structure and function of bacterial and fungal communities in organic horizons (Oe and Oa ) of acid forest soils. Liming increased soil pH, extractable calcium, and soil carbon stocks, reduced biomass-specific respiration, and caused major changes in the soil microbiome in the short and long term. More taxa responded to liming in the short term (70%) than in the long term (30%), with most showing consistent directional responses at both sites. The ratio of change in relative abundance between limed and reference sites was twofold higher at the long than the short-term site, indicating that the effects of liming grew over time. Liming impacts were most pronounced in fungi, as steep declines of dominant ectomycorrhizal fungi (Cenococcum and Russula) occurred at both sites. Liming favoured neutrophilic bacteria over acidophilic populations according to estimated environmental pH optima. Collectively, these results demonstrate that a liming-induced change of one pH unit has an immediate and persistent effect on the structure and function of microbial communities in acid forest soils. The corresponding suppression of respiration indicates that anthropogenic alterations of soil pH, as driven by acid deposition or liming, can affect forest floor C stocks due to pH-driven shifts in community structure.


Assuntos
Microbiota , Micorrizas , Solo/química , Concentração de Íons de Hidrogênio , Microbiologia do Solo , Carbono , Florestas , Bactérias/genética
3.
Int J Health Plann Manage ; 37(4): 1918-1925, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35384032

RESUMO

Vaccination is an important and cost-effective disease prevention and control strategy. Over the years, milestone discoveries in vaccine research and development as well as vaccine delivery systems, have contributed to expanded immunisation coverage and reduction in morbidity and mortality associated with vaccine-preventable diseases. While this outstanding development in vaccine delivery continues, there are considerable gaps in access to vaccines among populations living in fragile and conflict-affected zones which appeared to be the fault line of limited vaccine coverage. Despite progress in coronavirus disease 2019 (COVID-19) vaccine development, there are concerns about the feasibility of African countries affected by armed conflict and violence to effectively deliver COVID-19 vaccines at the unprecedented level required to fight against the virus. In this article we discuss the feasibility of access to COVID-19 vaccine among populations in conflict affected areas in Nigeria including methods that can be applied to reach and vaccinate populations in these settings.


Assuntos
COVID-19 , Vacinas , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Humanos , Nigéria , Vacinação
4.
Optom Vis Sci ; 98(7): 723-731, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34328451

RESUMO

SIGNIFICANCE: Sports vision is an emerging field that seeks to establish the relationships between visual function and sports performance. Here we provide the first critical review of empirical studies that attempt to link visual assessments and vision training to competitive game performance.Vision is essential to producing controlled movement, and therefore, it is intuitive that better visual abilities should relate to better sporting performance. This notion has been central to the field of sports vision, an area of study that seeks to determine the visual skills that underlie optimal sports performance and investigate approaches to train these abilities to improve sports performance. Although this field now contains hundreds of published articles addressing visual assessment and training in athletes, relatively few have attempted to directly link these capabilities to on-field production statistics from competitive matches. The objectives of this article are both to describe the theoretical and experimental framework necessary for such research and to critically review the empirical literature that has attempted to directly link visual assessments and/or training to athletic performance. We begin by describing why such associations are important and then provide an evidence-based framework for evaluating the quality of research in this domain. This is followed by a summary and review of the qualified literature that has addressed either relationships between baseline assessments and game performance or the effects of visual training interventions on game performance. Based on this review, it is concluded that, despite promising evidence supporting the role of vision in sports performance and improvements due to training, the specialty is still in need of methodological improvements. It is recommended that studies aim for larger better-powered studies, consistent and precise outcome measures, and greater scientific rigor such as obtained through randomized placebo-controlled designs with pre-registration of hypotheses.


Assuntos
Desempenho Atlético , Baixa Visão , Atletas , Humanos , Visão Ocular
5.
Neuroimage ; 211: 116596, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32014552

RESUMO

The brain is organized into networks that reorganize dynamically in response to cognitive demands and exogenous stimuli. In recent years, repetitive transcranial magnetic stimulation (rTMS) has gained increasing use as a noninvasive means to modulate cortical physiology, with effects both proximal to the stimulation site and in distal areas that are intrinsically connected to the proximal target. In light of these network-level neuromodulatory effects, there has been a rapid growth in studies attempting to leverage information about network connectivity to improve neuromodulatory control and intervention outcomes. However, the mechanisms-of-action of rTMS on network-level effects remain poorly understood and is based primarily on heuristics from proximal stimulation findings. To help bridge this gap, the current paper presents a systematic review of 33 rTMS studies with baseline and post-rTMS measures of fMRI resting-state functional connectivity (RSFC). Literature synthesis revealed variability across studies in stimulation parameters, studied populations, and connectivity analysis methodology. Despite this variability, it is observed that active rTMS induces significant changes on RSFC, but the prevalent low-frequency-inhibition/high-frequency-facilitation heuristic endorsed for proximal rTMS effects does not fully describe distal connectivity findings. This review also points towards other important considerations, including that the majority of rTMS-induced changes were found outside the stimulated functional network, suggesting that rTMS effects tend to spread across networks. Future studies may therefore wish to adopt conventions and systematic frameworks, such as the Yeo functional connectivity parcellation atlas adopted here, to better characterize network-level effect that contribute to the efficacy of these rapidly developing noninvasive interventions.


Assuntos
Encéfalo/fisiologia , Conectoma , Imageamento por Ressonância Magnética , Rede Nervosa/fisiologia , Estimulação Magnética Transcraniana , Humanos
6.
Transfusion ; 60(11): 2622-2632, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32743810

RESUMO

BACKGROUND: The Verax PGD rapid test for bacteria in platelets (PLTs) has been updated to simplify workflow and improve specificity and sensitivity by employing a novel sequential format. The performance of this updated version, called PGDprime, was evaluated to determine its suitability for use as an FDA-cleared "safety measure" to supplant the current PGD test. STUDY DESIGN AND METHODS: Three consecutive cGMP-manufactured lots of PGDprime were evaluated for specificity (at three separate sites), sensitivity, reproducibility, interfering substances, assay robustness, and detection in analytical growth and ultralow-inoculum growth studies. PGDprime's performance was compared to that of PGD. RESULTS: Specificity studies yielded no false-positive results among 3802 individual indate PLTs of seven different types (observed specificity, 100%). PGDprime detected all 10 PGD claim bacteria at the same limit of detection or better. Wild-type Gram-negative bacteria growing in PLTs were detected at earlier elapsed times than PGD by 12 to 30 hours. In growth studies, PGDprime detected bacteria growing in PLTs within the same 12-hour interval as PGD or 12 to 48 hours earlier. Assay reproducibility was not affected by operator, day of test, or manufacturing lot. PGDprime tolerated a wide variation in volume transfers, timing, temperature, and relative humidity and was not affected by 15 of 16 potential interferents found in samples at extremely high or low levels. CONCLUSION: The PGD test has been successfully updated to PGDprime with an innovative sequential assay format to deliver a robust simplified workflow and improved specificity and sensitivity.


Assuntos
Técnicas de Tipagem Bacteriana , Plaquetas/microbiologia , Segurança do Sangue , Bactérias Gram-Negativas/classificação , Técnicas Bacteriológicas , Humanos
7.
Plant Cell ; 28(1): 146-59, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26744216

RESUMO

NOD-like receptors (NLRs) are central components of the plant immune system. L6 is a Toll/interleukin-1 receptor (TIR) domain-containing NLR from flax (Linum usitatissimum) conferring immunity to the flax rust fungus. Comparison of L6 to the weaker allele L7 identified two polymorphic regions in the TIR and the nucleotide binding (NB) domains that regulate both effector ligand-dependent and -independent cell death signaling as well as nucleotide binding to the receptor. This suggests that a negative functional interaction between the TIR and NB domains holds L7 in an inactive/ADP-bound state more tightly than L6, hence decreasing its capacity to adopt the active/ATP-bound state and explaining its weaker activity in planta. L6 and L7 variants with a more stable ADP-bound state failed to bind to AvrL567 in yeast two-hybrid assays, while binding was detected to the signaling active variants. This contrasts with current models predicting that effectors bind to inactive receptors to trigger activation. Based on the correlation between nucleotide binding, effector interaction, and immune signaling properties of L6/L7 variants, we propose that NLRs exist in an equilibrium between ON and OFF states and that effector binding to the ON state stabilizes this conformation, thereby shifting the equilibrium toward the active form of the receptor to trigger defense signaling.


Assuntos
Linho/metabolismo , Modelos Biológicos , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Morte Celular , Linho/citologia , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Proteínas de Plantas/química , Polimorfismo Genético , Ligação Proteica , Estrutura Terciária de Proteína , Receptores de Superfície Celular/química , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência
8.
Environ Sci Technol ; 53(7): 3620-3633, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30830765

RESUMO

Little is known about the regional extent and variability of nitrate from atmospheric deposition that is transported to streams without biological processing in forests. We measured water chemistry and isotopic tracers (δ18O and δ15N) of nitrate sources across the Northern Forest Region of the U.S. and Canada and reanalyzed data from other studies to determine when, where, and how unprocessed atmospheric nitrate was transported in catchments. These inputs were more widespread and numerous than commonly recognized, but with high spatial and temporal variability. Only 6 of 32 streams had high fractions (>20%) of unprocessed atmospheric nitrate during baseflow. Seventeen had high fractions during stormflow or snowmelt, which corresponded to large fractions in near-surface soil waters or groundwaters, but not deep groundwater. The remaining 10 streams occasionally had some (<20%) unprocessed atmospheric nitrate during stormflow or baseflow. Large, sporadic events may continue to be cryptic due to atmospheric deposition variation among storms and a near complete lack of monitoring for these events. A general lack of observance may bias perceptions of occurrence; sustained monitoring of chronic nitrogen pollution effects on forests with nitrate source apportionments may offer insights needed to advance the science as well as assess regulatory and management schemes.


Assuntos
Florestas , Nitratos , Canadá , Monitoramento Ambiental , Nitrogênio , Rios
9.
J Environ Qual ; 47(3): 410-418, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29864170

RESUMO

Declines in acidic deposition across Europe and North America have led to decreases in surface water acidity and signs of chemical recovery of soils from acidification. To better understand the link between recovery of soils and surface waters, chemical trends in precipitation, soils, and streamwater were investigated in three watersheds representing a depositional gradient from high to low across the northeastern United States. Significant declines in concentrations of H (ranging from -1.2 to -2.74 microequivalents [µeq] L yr), NO (ranging from -0.6 to -0.84 µeq L yr), and SO (ranging from -0.95 to -2.13 µeq L yr) were detected in precipitation in the three watersheds during the period 1999 to 2013. Soil chemistry in the A horizon of the watershed with the greatest decrease in deposition showed significant decreases in exchangeable Al and increases in exchangeable bases. Soil chemistry did not significantly improve during the study in the other watersheds, and base saturation in the Oa and upper B horizons significantly declined in the watershed with the smallest decrease in deposition. Streamwater SO concentrations significantly declined in all three streams (ranging from -2.01 to -2.87 µeq L yr) and acid neutralizing capacity increased (ranging from 1.38 to 1.60 µeq L yr) in the two streams with the greatest decreases in deposition. Recovery of soils has likely been limited by decades of acid deposition that have leached base cations from soils with base-poor parent material.


Assuntos
Rios/química , Solo/química , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , New England
10.
J Sports Sci ; 36(2): 171-179, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28282749

RESUMO

This study aimed to evaluate the possibility that differences in sensorimotor abilities exist between hitters and pitchers in a large cohort of baseball players of varying levels of experience. Secondary data analysis was performed on 9 sensorimotor tasks comprising the Nike Sensory Station assessment battery. Bayesian hierarchical regression modelling was applied to test for differences between pitchers and hitters in data from 566 baseball players (112 high school, 85 college, 369 professional) collected at 20 testing centres. Explanatory variables including height, handedness, eye dominance, concussion history, and player position were modelled along with age curves using basis regression splines. Regression analyses revealed better performance for hitters relative to pitchers at the professional level in the visual clarity and depth perception tasks, but these differences did not exist at the high school or college levels. No significant differences were observed in the other 7 measures of sensorimotor capabilities included in the test battery, and no systematic biases were found between the testing centres. These findings, indicating that professional-level hitters have better visual acuity and depth perception than professional-level pitchers, affirm the notion that highly experienced athletes have differing perceptual skills. Findings are discussed in relation to deliberate practice theory.


Assuntos
Desempenho Atlético/fisiologia , Beisebol/fisiologia , Percepção de Profundidade/fisiologia , Acuidade Visual/fisiologia , Adolescente , Adulto , Fatores Etários , Teorema de Bayes , Humanos , Masculino , Destreza Motora/fisiologia , Córtex Sensório-Motor/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
11.
J Environ Manage ; 191: 19-27, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28082250

RESUMO

Sustaining recent progress in mitigating acid pollution could require lower emissions caps that will give rise to real or perceived tradeoffs between healthy ecosystems and inexpensive energy. Because most impacts of acid rain affect ecosystem functions that are poorly understood by policy-makers and the public, an ecosystem services (ES) framework can help to measure how pollution affects human well-being. Focused on the Adirondack region (USA), a global 'hot-spot' of acid pollution, we measured how the chronic acidification of the region's forests, lakes, and streams has affected the potential economic and cultural benefits they provide to society. We estimated that acid-impaired hardwood forests provide roughly half of the potential benefits of forests on moderate to well-buffered soils - an estimated loss of ∼ $10,000 ha-1 in net present value of wood products, maple syrup, carbon sequestration, and visual quality. Acidic deposition has had only nominal impact - relative to the effects of surficial geology and till depth - on the capacity of Adirondack lakes and streams to provide water suitable for drinking. However, as pH declines in lakes, the estimated value of recreational fishing decreases significantly due to loss of desirable fish such as trout. Hatchery stocking programs have partially offset the pollution-mediated losses of fishery value, most effectively in the pH range 4.8-5.5, but are costly and limited in scope. Although any estimates of the monetary 'damages' of acid rain have significant uncertainties, our findings highlight some of the more tangible economic and cultural benefits of pollution mitigation efforts, which continue to face litigation and political opposition.


Assuntos
Ecossistema , Florestas , Chuva Ácida , Animais , Poluição Ambiental , Humanos , Lagos
12.
BMC Genomics ; 17: 667, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27550217

RESUMO

BACKGROUND: Rust fungi are an important group of plant pathogens that cause devastating losses in agricultural, silvicultural and natural ecosystems. Plants can be protected from rust disease by resistance genes encoding receptors that trigger a highly effective defence response upon recognition of specific pathogen avirulence proteins. Identifying avirulence genes is crucial for understanding how virulence evolves in the field. RESULTS: To facilitate avirulence gene cloning in the flax rust fungus, Melampsora lini, we constructed a high-density genetic linkage map using single nucleotide polymorphisms detected in restriction site-associated DNA sequencing (RADseq) data. The map comprises 13,412 RADseq markers in 27 linkage groups that together span 5860 cM and contain 2756 recombination bins. The marker sequences were used to anchor 68.9 % of the M. lini genome assembly onto the genetic map. The map and anchored assembly were then used to: 1) show that M. lini has a high overall meiotic recombination rate, but recombination distribution is uneven and large coldspots exist; 2) show that substantial genome rearrangements have occurred in spontaneous loss-of-avirulence mutants; and 3) identify the AvrL2 and AvrM14 avirulence genes by map-based cloning. AvrM14 is a dual-specificity avirulence gene that encodes a predicted nudix hydrolase. AvrL2 is located in the region of the M. lini genome with the lowest recombination rate and encodes a small, highly-charged proline-rich protein. CONCLUSIONS: The M. lini high-density linkage map has greatly advanced our understanding of virulence mechanisms in this pathogen by providing novel insights into genome variability and enabling identification of two new avirulence genes.


Assuntos
Basidiomycota/genética , Mapeamento Cromossômico , Genoma Fúngico , Genômica , Virulência/genética , Sequência de Aminoácidos , Basidiomycota/patogenicidade , Biologia Computacional/métodos , Frequência do Gene , Loci Gênicos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Perda de Heterozigosidade , Mutação , Fenótipo , Polimorfismo de Nucleotídeo Único , Recombinação Genética
14.
Environ Sci Technol ; 49(22): 13103-11, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26495963

RESUMO

Decreasing trends in acidic deposition levels over the past several decades have led to partial chemical recovery of surface waters. However, depletion of soil Ca from acidic deposition has slowed surface water recovery and led to the impairment of both aquatic and terrestrial ecosystems. Nevertheless, documentation of acidic deposition effects on soils has been limited, and little is known regarding soil responses to ongoing acidic deposition decreases. In this study, resampling of soils in eastern Canada and the northeastern U.S. was done at 27 sites exposed to reductions in wet SO4(2-) deposition of 5.7-76%, over intervals of 8-24 y. Decreases of exchangeable Al in the O horizon and increases in pH in the O and B horizons were seen at most sites. Among all sites, reductions in SO4(2-) deposition were positively correlated with ratios (final sampling/initial sampling) of base saturation (P < 0.01) and negatively correlated with exchangeable Al ratios (P < 0.05) in the O horizon. However, base saturation in the B horizon decreased at one-third of the sites, with no increases. These results are unique in showing that the effects of acidic deposition on North American soils have begun to reverse.


Assuntos
Ácidos/química , Florestas , Solo/química , Alumínio/análise , Atmosfera/química , Canadá , New England , Poluentes do Solo/análise
15.
Environ Pollut ; 343: 123273, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38160771

RESUMO

Studies of recovery from acidic deposition have focused on reversal of acidification and its associated effects, but as recovery proceeds slowly, chemical dilution of surface waters is emerging as a key factor in the recovery process that has significant chemical and biological implications. This investigation uses long-term chemical records from 130 streams in the Adirondack region of New York, USA, to evaluate the role of ongoing decreases in conductance, an index of dilution, in the recovery of these streams. Stream chemistry data spanning up to 40 years (1980s-2022) showed that acid-neutralizing capacity has increased in 92% of randomly selected streams, but that harmful levels of acidification still occur in 37% of these streams. Conductance and Ca2+ concentrations decreased in 79% of streams, and SO42- concentrations in streams continued to show strong decreases but remained several times higher than concentrations in precipitation. These changes were ongoing through 2022 even though acidic deposition levels were approaching those estimated for pre-industrialization. Further dilution is continuing through ongoing decreases in stream SO42-. Nevertheless, Ca2+ continued to be leached from soils by SO42-, organic acids and NO3-, limiting the replenishment of available soil Ca2+, a prerequisite to stem further dilution of stream water.


Assuntos
Água Doce , Rios , Concentração de Íons de Hidrogênio , Água , Compostos Orgânicos , Ácidos , Solo , Monitoramento Ambiental
16.
Plant Cell ; 22(6): 2017-32, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20525849

RESUMO

Translocation of pathogen effector proteins into the host cell cytoplasm is a key determinant for the pathogenicity of many bacterial and oomycete plant pathogens. A number of secreted fungal avirulence (Avr) proteins are also inferred to be delivered into host cells, based on their intracellular recognition by host resistance proteins, including those of flax rust (Melampsora lini). Here, we show by immunolocalization that the flax rust AvrM protein is secreted from haustoria during infection and accumulates in the haustorial wall. Five days after inoculation, the AvrM protein was also detected within the cytoplasm of a proportion of plant cells containing haustoria, confirming its delivery into host cells during infection. Transient expression of secreted AvrL567 and AvrM proteins fused to cerulean fluorescent protein in tobacco (Nicotiana tabacum) and flax cells resulted in intracellular accumulation of the fusion proteins. The rust Avr protein signal peptides were functional in plants and efficiently directed fused cerulean into the secretory pathway. Thus, these secreted effectors are internalized into the plant cell cytosol in the absence of the pathogen, suggesting that they do not require a pathogen-encoded transport mechanism. Uptake of these proteins is dependent on signals in their N-terminal regions, but the primary sequence features of these uptake regions are not conserved between different rust effectors.


Assuntos
Basidiomycota/patogenicidade , Linho/imunologia , Proteínas Fúngicas/metabolismo , Nicotiana/microbiologia , Doenças das Plantas/microbiologia , Sequência de Aminoácidos , Citoplasma/metabolismo , Linho/microbiologia , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Sinais Direcionadores de Proteínas , Transporte Proteico , Nicotiana/imunologia
17.
Environ Sci Technol ; 47(13): 7095-100, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23751119

RESUMO

Increasing pH and decreasing Al in surface waters recovering from acidification have been accompanied by increasing concentrations of dissolved organic carbon (DOC) and associated organic acids that partially offset pH increases and complicate assessments of recovery from acidification. To better understand the processes of recovery, monthly chemistry from 42 lakes in the Adirondack region, NY, collected from 1994 to 2011, were used to (1) evaluate long-term changes in DOC and associated strongly acidic organic acids and (2) use the base-cation surplus (BCS) as a chemical index to assess the effects of increasing DOC concentrations on the Al chemistry of these lakes. Over the study period, the BCS increased (p < 0.01) and concentrations of toxic inorganic monomeric Al (IMAl) decreased (p < 0.01). The decreases in IMAl were greater than expected from the increases in the BCS. Higher DOC concentrations that increased organic complexation of Al resulted in a decrease in the IMAl fraction of total monomeric Al from 57% in 1994 to 23% in 2011. Increasing DOC concentrations have accelerated recovery in terms of decreasing toxic Al beyond that directly accomplished by reducing atmospheric deposition of strong mineral acids.


Assuntos
Alumínio/análise , Carbono/análise , Lagos/análise , Poluentes Químicos da Água/análise , Chuva Ácida , Alumínio/química , Monitoramento Ambiental , New York , Poluentes Químicos da Água/química
18.
J Environ Qual ; 42(3): 623-39, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673928

RESUMO

Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest ecosystems through repeated measurements are largely nascent and uncoordinated. In eastern North America, repeated soil sampling has begun to provide valuable information on environmental problems such as air pollution. This review synthesizes the current state of the science to further the development and use of soil resampling as an integral method for recording and understanding environmental change in forested settings. The origins of soil resampling reach back to the 19th century in England and Russia. The concepts and methodologies involved in forest soil resampling are reviewed and evaluated through a discussion of how temporal and spatial variability can be addressed with a variety of sampling approaches. Key resampling studies demonstrate the type of results that can be obtained through differing approaches. Ongoing, large-scale issues such as recovery from acidification, long-term N deposition, C sequestration, effects of climate change, impacts from invasive species, and the increasing intensification of soil management all warrant the use of soil resampling as an essential tool for environmental monitoring and assessment. Furthermore, with better awareness of the value of soil resampling, studies can be designed with a long-term perspective so that information can be efficiently obtained well into the future to address problems that have not yet surfaced.


Assuntos
Mudança Climática , Ecossistema , Poluição do Ar , Monitoramento Ambiental , Florestas , Solo , Árvores
19.
Rev Neurosci ; 34(3): 349-364, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36310385

RESUMO

The last decades have seen a rise in the use of transcranial direct current stimulation (tDCS) approaches to modulate brain activity and associated behavior. Concurrently, eye tracking (ET) technology has improved to allow more precise quantitative measurement of gaze behavior, offering a window into the mechanisms of vision and cognition. When combined, tDCS and ET provide a powerful system to probe brain function and measure the impact on visual function, leading to an increasing number of studies that utilize these techniques together. The current pre-registered, systematic review seeks to describe the literature that integrates these approaches with the goal of changing brain activity with tDCS and measuring associated changes in eye movements with ET. The literature search identified 26 articles that combined ET and tDCS in a probe-and-measure model and are systematically reviewed here. All studies implemented controlled interventional designs to address topics related to oculomotor control, cognitive processing, emotion regulation, or cravings in healthy volunteers and patient populations. Across these studies, active stimulation typically led to changes in the number, duration, and timing of fixations compared to control stimulation. Notably, half the studies addressed emotion regulation, each showing hypothesized effects of tDCS on ET metrics, while tDCS targeting the frontal cortex was widely used and also generally produced expected modulation of ET. This review reveals promising evidence of the impact of tDCS on eye movements and associated psychological function, offering a framework for effective designs with recommendations for future studies.


Assuntos
Fenômenos Fisiológicos do Sistema Nervoso , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Movimentos Oculares , Córtex Pré-Frontal/fisiologia , Cognição/fisiologia
20.
PLoS One ; 18(1): e0278689, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656847

RESUMO

Baseball is an international sport with participation from tens of thousands of people worldwide. In the United States, the Prospect Development Pipeline (PDP) is a collaborative effort between Major League Baseball and USA Baseball to establish a developmental pipeline leading to the professional draft. Players participating in the PDP undergo comprehensive evaluations that measure athletic performance, speed-of-processing, visual function, and on-field talent. The present study evaluated data from 1352 elite junior male PDP participants (aged 14 to 21) who signed informed consent, collected between 2017 and 2020, to identify latent abilities and their association with player specialization. Data were first subjected to Exploratory Factor Analysis (EFA) to reduce the 22 measured variables to a smaller set of latent abilities. The resulting factors were evaluated using multiple linear regression to predict each factor using age, height, weight, and position. EFA revealed a combination of physical and psychomotor skills accounting for 52% of the overall variance that grouped into four abilities: grip strength, functional vision, explosiveness, and rapid decision-making. Regression analyses demonstrated that these skills are associated with position assignments, controlling for age, weight, and height, and revealed that outfielders are the most explosive, infielders perform best on psychomotor measures, and catchers perform best on functional vision tests (ps < 0.001). These findings indicate skills that contribute to player specialization, providing new information about the developmental trajectory of junior elite baseball athletes that can be used for scouting and player development.


Assuntos
Desempenho Atlético , Beisebol , Humanos , Masculino , Adolescente , Estados Unidos , Atletas , Especialização
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