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The whiteleg marine shrimp Penaeus vannamei, originally from the Eastern Pacific Ocean, now inhabits tropical waters across Asia and Central and Southern America. This benthic species exhibits rapid growth, wide salinity and temperature tolerance, and disease resistance. These physiological traits have led to extensive research on its osmoregulatory mechanisms, including next-generation sequencing, transcriptomic analyses, and lipidomic responses. In crustaceans, osmotic and ionic homeostasis is primarily maintained by the membrane-bound metalloenzyme (Na+, K+)-ATPase. However, little is known about how various ligands modulate this enzyme in P. vannamei. Here, we examined the kinetic characteristics of the gill (Na+, K+)-ATPase to get biochemical insights into its modulation. A prominent immunoreactive band of ~120 kDa, corresponding to the (Na+, K+)-ATPase alpha-subunit, was identified. The enzyme exhibited two ATP hydrolyzing sites with K0.5 = 0.0003 ± 0.00002 and 0.05 ± 0.003 mmol L-1 and was stimulated by low sodium ion concentrations. Potassium and ammonium ions also stimulated enzyme activity with similar K0.5 values of 0.08 ± 0.004 and 0.06 ± 0.003 mmol L-1, respectively. Ouabain inhibition profile suggested a single enzyme isoform with a KI value of 2.10 ± 0.16 mmol L-1. Our findings showed significant kinetic differences in the (Na+, K+)-ATPase in Penaeus vannamei compared to marine and freshwater crustaceans. We expect our results to enhance understanding of the modulation of gill (Na+, K+)-ATPase in Penaeus vannamei and to provide a valuable tool for studying the shrimp's biochemical acclimation to varying salinity conditions.
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BACKGROUND: Tractors and quad bikes pose a significant risk of fatal injuries among farmers, particularly affecting older farmers. This study aimed to explore the barriers and facilitators to the adoption of machine related safety behaviors among older farmers in Irish farm settings. METHOD: Four focus groups were conducted via Zoom in February 2021. Nineteen Irish farmers from four farm types participated. The discussions were audio-recorded, transcribed verbatim, and analyzed using an inductive, reflexive thematic analysis approach. The themes identified were then mapped to the COM-B (Capability-Opportunity-Motivation) model, providing a systematic theoretical basis for designing a future intervention to reduce machine-related accidents. RESULTS: The analysis identified five inductive themes that encompassed both barriers and facilitators in farm safety practices: (1) Capability to manage competing responsibilities; (2) Characteristics of the farm and its work environment; (3) Availability and affordability of resources; (4) Prevailing sociocultural opportunities; and (5) Perceived likelihood and cost-benefit analysis in safety decision-making. These themes captured the complex interplay of capability, opportunity, and motivation in farmers' decision-making processes. The study also revealed limitations in existing interventions, such as voluntary guidelines and educational methods, in effectively addressing these barriers. CONCLUSIONS: Farmers' abilities (capability), prevailing sociocultural factors, resource availability (opportunity), and their perceived consequences and benefits (motivation) affect how safely they work with machines. The study emphasizes the need for comprehensive, theory-driven approaches that consider the interplay of capability, opportunity, and motivational factors that may support or impede machine safety. Understanding the challenges faced by Irish farmers highlights potential strategies for safety intervention, and these strategies should be co-designed with farmers and attentive to the local context. PRACTICAL APPLICATIONS: The study provides a template for understanding farmers' perspectives using the COM-B model. The findings can inform the development of theoretically informed intervention strategies based on the Behavior Change Wheel framework.
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Fazendeiros , Grupos Focais , Humanos , Fazendeiros/psicologia , Fazendeiros/estatística & dados numéricos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Irlanda , Acidentes de Trabalho/prevenção & controle , Fazendas , Agricultura , Saúde Ocupacional , Pesquisa Qualitativa , Motivação , Tomada de DecisõesRESUMO
Learning is a taxonomically widespread process by which animals change their behavioural responses to stimuli as a result of experience. In this way, it plays a crucial role in the development of individual behaviour and underpins substantial phenotypic variation within populations. Nevertheless, the impact of learning in social contexts on evolutionary change is not well understood. Here, we develop game theoretical models of competition for resources in small groups (e.g. producer-scrounger and hawk-dove games) in which actions are controlled by reinforcement learning and show that biases in the subjective valuation of different actions readily evolve. Moreover, in many cases, the convergence stable levels of bias exist at fitness minima and therefore lead to disruptive selection on learning rules and, potentially, to the evolution of genetic polymorphisms. Thus, we show how reinforcement learning in social contexts can be a driver of evolutionary diversification. In addition, we consider the evolution of ability in our games, showing that learning can also drive disruptive selection on the ability to perform a task.
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Evolução Biológica , Comportamento Competitivo , Teoria dos Jogos , Aprendizagem , Animais , Reforço PsicológicoRESUMO
Decapod Crustacea exhibit a marine origin, but many taxa have occupied environments ranging from brackish to fresh water and terrestrial habitats, overcoming their inherent osmotic challenges. Osmotic and ionic regulation is achieved by the gill epithelia, driven by two active ATP-hydrolyzing ion transporters, the basal (Na+, K+)-ATPase and the apical V(H+)-ATPase. The kinetic characteristic of gill (Na+, K+)-ATPase and the mRNA expression of its α subunit have been widely studied in various decapod species under different salinity challenges. However, the evolution of the primary structure has not been explored, especially considering the functional modifications associated with decapod phylogeny. Here, we proposed a model for the topology of the decapod α subunit, identifying the sites and motifs involved in its function and regulation, as well as the patterns of its evolution assuming a decapod phylogeny. We also examined both the amino acid substitutions and their functional implications within the context of biochemical and physiological adaptation. The α-subunit of decapod crustaceans shows greater conservation (â¼94% identity) compared to the ß-subunit (â¼40%). While the binding sites for ATP and modulators are conserved in the decapod enzyme, the residues involved in the α-ß interaction are only partially conserved. In the phylogenetic context of the complete sequence of (Na+, K+)-ATPase α-subunit, most substitutions appear to be characteristic of the entire group, with specific changes for different subgroups, especially among brachyuran crabs. Interestingly, there was no consistent separation of α-subunit partial sequences related to habitat, suggesting that the convergent evolution for freshwater or terrestrial modes of life is not correlated with similar changes in the enzyme's primary amino acid sequence.
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Sequência de Aminoácidos , Decápodes , Osmorregulação , Filogenia , ATPase Trocadora de Sódio-Potássio , Animais , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , ATPase Trocadora de Sódio-Potássio/química , Osmorregulação/genética , Decápodes/genética , Decápodes/enzimologia , Decápodes/fisiologia , Evolução Molecular , Brânquias/metabolismo , Brânquias/enzimologiaRESUMO
We broaden the clinical versatility of human nasal epithelial (HNE) cells. HNEs were isolated from 10 participants harboring cystic fibrosis transmembrane conductance regulator (CFTR) variants: 9 with rare variants (Q359R [n = 2], G480S, R334W [n = 5], and R560T) and 1 harboring R117H;7T;TG10/5T;TG12. Cultures were differentiated at the air-liquid interface. CFTR function was measured in Ussing chambers at three conditions: baseline, ivacaftor, and elexacaftor + tezacaftor + ivacaftor (ETI). Four participants initiated modulators. Q359R HNEs had 5.4% (% wild-type) baseline CFTR function and 25.5% with ivacaftor. With therapy, sweat [Cl-] decreased and symptoms resolved. G480S HNEs had 4.1% baseline and 32.1% CFTR function with ETI. Clinically, forced expiratory volume in 1 second increased and sweat [Cl-] decreased (119 to 46 mmol/L) with ETI. In vitro cultures derived from 5 participants harboring R334W showed a moderate increase in CFTR function with exposure to modulators. For one of these participants, ETI was begun in vivo; symptoms and forced expiratory volume in 1 second improved. The c.1679G>C (R560T) HNEs had less than 4% baseline CFTR function and no modulator response. RNA analysis confirmed that c.1679G>C completely missplices. A symptomatic patient harboring R117H;7T;TG10/5T;TG12 exhibited reduced CFTR function (17.5%) in HNEs, facilitating a diagnosis of mild CF. HNEs responded to modulators (ivacaftor: 32.8%, ETI: 55.5%), and, since beginning therapy, lung function improved. We reaffirm HNE use for guiding therapeutic approaches, inform predictions on modulator response (e.g., R334W), and closely assess variants that affect splicing (e.g., c.1679G>C). Notably, functional studies in HNEs harboring R117H;7T;TG10/5T;TG12 facilitated a diagnosis of mild CF, suggesting the use for HNE functional studies as a clinical diagnostic test.
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Aminofenóis , Regulador de Condutância Transmembrana em Fibrose Cística , Fibrose Cística , Células Epiteliais , Mucosa Nasal , Medicina de Precisão , Quinolonas , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Medicina de Precisão/métodos , Quinolonas/farmacologia , Aminofenóis/farmacologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Fibrose Cística/metabolismo , Mucosa Nasal/metabolismo , Mucosa Nasal/efeitos dos fármacos , Feminino , Adulto , Masculino , Indóis/farmacologia , Benzodioxóis/farmacologia , Suor/metabolismo , Células Cultivadas , Pirróis/farmacologia , Adulto Jovem , Agonistas dos Canais de Cloreto/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Mutação , Combinação de Medicamentos , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Measuring attitudes of farmers to safe farming practices using quantitative causal relationship approaches is central to improving understanding of (un)safe practices. This knowledge is important in the development of effective farm safety interventions. However, the accuracy of quantitative attitudinal studies in explaining farmers' decision-making faces a potential measurement challenge, i.e. a high level of optimism bias. In this paper, we present research that develops and tests farm safety attitudinal questions that are framed around "real-life" farming practices with the objective of reducing optimism bias. METHODS: We apply construal level theory (CLT) to support the design of vignettes that reflect common risk scenarios faced by farmers. Applying qualitative analysis of 274 fatal farm incidents that occurred in Ireland between 2004 and 2018 we identify the occupational behaviors (what farmers do), social (who are farmers), spatial (where farming takes place), and temporal (when farming happens) dimensions of risks resulting in most deaths. The results informed subsequent co-design activities with farm safety experts and farm advisors to develop "real-life" scenarios, attitudinal questions, and response options. The questionnaire was piloted and subsequently implemented to collect data from a sample of 381 farmers with either tractors or livestock. The results of the survey were compared to previous attitudinal research on farmer's attitudes to safety in Ireland to establish if there was as follows: i) increased variance in the responses, and ii) a statistically significant difference in the attitudes of respondents compared to the results reported in previous studies. RESULTS: The findings established that when farmers were provided with real-life scenarios, their responses were less optimistic and more varied, i.e. there was a greater range of responses, compared to previous studies. CONCLUSION: Applying CTL to the development of attitudinal survey instruments anchors attitudinal questions within farming specific occupational, social, spatial, and temporal contexts. The use of vignettes that draw on real-life scenarios offers the potential for improved design of surveys that seek to understand farmer/worker practices. The results suggest that this approach can improve the measurement of attitudes to farm safety.
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Agricultura , Fazendeiros , Otimismo , Humanos , Fazendeiros/psicologia , Fazendeiros/estatística & dados numéricos , Irlanda , Masculino , Feminino , Inquéritos e Questionários , Adulto , Saúde Ocupacional , Pessoa de Meia-Idade , Fazendas , Atitude , Acidentes de Trabalho/prevenção & controle , IdosoRESUMO
The Macrobrachium amazonicum complex is composed of at least the Macrobrachium amazonicum and Macrobrachium pantanalense species, with the latter described from specimens originally identified as part of an endemic M. amazonicum population in the Brazilian Pantanal region. While there may be a reproductive barrier between these two Macrobrachium species, both are phylogenetically close, with small genetic distance. However, there is currently no available biochemical information of Macrobrachium pantanalense (Na+, K+)-ATPase. Here, we report the kinetic characteristics of the gill (Na+, K+)-ATPase in two populations of M. pantanalense from Baiazinha Lagoon (Miranda, MS, Brazil) and Araguari River (Uberlândia, MG, Brazil), and compare them with Macrobrachium amazonicum populations from the Paraná-Paraguay River Basin. (Na+, K+)-ATPase activities were 67.9 ± 3.4 and 93.3 ± 4.1 nmol Pi min-1 mg-1 protein for the Baiazinha Lagoon and Araguari River populations, respectively. Two ATP hydrolyzing sites were observed for the Araguari River population while a single ATP site was observed for the Baiazinha Lagoon shrimps. Compared to the Araguari River population, a 3-fold greater apparent affinity for Mg2+ and Na+ was estimated for the Baiazinha Lagoon population, but no difference in K+ affinity and ouabain inhibition was seen. The kinetic differences observed in the gill (Na+, K+)-ATPase between the two populations of M. pantanalense, compared with those of various M. amazonicum populations, highlight interspecific divergence within the Macrobrachium genus, now examined from a biochemical perspective.
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Brânquias , Palaemonidae , ATPase Trocadora de Sódio-Potássio , Animais , ATPase Trocadora de Sódio-Potássio/metabolismo , ATPase Trocadora de Sódio-Potássio/genética , Palaemonidae/genética , Palaemonidae/enzimologia , Brânquias/metabolismo , Brânquias/enzimologia , Brasil , Rios , CinéticaRESUMO
Fidelity between teaching activities and assessment methods is an important goal of knowledge and performance evaluations in medical education. Ideally, assessment methods provide evidence of learning that reflects the types of knowledge described in the learning objectives of the course. The most reliable assessments involve the same or similar tasks as those used during the instructional components of the course. Our preclinical human anatomy course includes, in addition to traditional lecture and cadaver-based laboratory learning activities, a series of applied human anatomy learning activities intended to emphasize human anatomy as it is encountered in living human individuals. The learning activities involve psychomotor behaviors including inspection, palpation, and auscultation, techniques used in the physical examination, as well as other activities designed to emphasize anatomical structures and tissues as they may be found in patient populations. We describe here our method for measuring student success in learning human anatomy in this manner, highlighting the direct linkage between the learning activities and the assessment tasks. We describe our performance scoring method and how we include this data in the calculation of an anatomy examination grade. As an indicator of our success with this approach, we include performance scores for the applied anatomy questions included on the laboratory component of our unit examinations for two successive academic years. We conclude with summary comments from students regarding the applied anatomy learning activities and assessment approach and offer suggestions for addressing specific challenges associated with the use of these types of assessment methods.
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Anatomia , Educação de Graduação em Medicina , Avaliação Educacional , Anatomia/educação , Humanos , Avaliação Educacional/métodos , Avaliação Educacional/estatística & dados numéricos , Educação de Graduação em Medicina/métodos , Estudantes de Medicina/psicologia , Estudantes de Medicina/estatística & dados numéricos , Currículo , Cadáver , AprendizagemRESUMO
OBJECTIVE: Generation of reliable data underpins the effectiveness of Occupational Health and Safety (OHS) surveillance systems. Despite the importance of understanding OHS data systems, there are few papers that provide overviews of their structure and/or content. This paper introduces a basic framework for assessing OHS data systems that will be of use to researchers internationally. We applied this approach to assess the Irish OHS data system by undertaking a data mapping exercise. METHOD: We developed a checklist based on recommendations of monitoring and measurement of OHS proposed by the National Academies of Sciences, Engineering, and Medicine (USA). An assessment of published reports that present systematic OHS surveillance data was undertaken to identify the institutions or organisations responsible for collecting and curating the data, their remit, and, associated with this, their respective case definitions. We then provide an overview of the variables collected and these are then mapped against the checklist. RESULTS: The assessment highlights that whilst the farm fatalities dataset provides complete coverage of all fatalities, regardless of age or employment status, the same is not true of the three non-fatal injuries datasets reviewed. There are important differences in the data collection methods and, associated with this, which populations are covered. PRACTICAL APPLICATION: The assessment approach provides valuable insights into the strengths and weaknesses of a critical element of OHS surveillance systems, namely the production of datasets. This knowledge is important for researchers as understanding the data that informs their research is fundamental to good science. It is critical for policy-makers and other stakeholders to understand the strengths and weaknesses on which OHS policy, strategies, or education and training interventions are developed.
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Saúde Ocupacional , Traumatismos Ocupacionais , Humanos , Fazendas , Sistemas de Dados , Traumatismos Ocupacionais/epidemiologiaRESUMO
OBJECTIVES: This paper sought to determine risk factors of occupational injury in the Irish dairy farming sector and to estimate the roles of both dairying expansion and the discipline of agricultural extension in influencing reducing injury occurrence. METHODS: Data for this study was obtained via the Irish National Farm Survey (NFS). In total, 260 farm (83.6% of NFS dairy farm sample) workplace injury survey questionnaires were completed by NFS recorders by interviewing principal farm operators for year 2017. Injury survey data was analysed for 48 variables in conjunction with NFS core farm socio-economic, physical and financial data. Additionally, core data from 2010 for 78.5% of farms surveyed in 2017 was included in the study. Data were analysed using a three-step statistical testing process which met all Binary Logistic Regression assumptions. RESULTS: The study found that dairy farms had a higher farm workplace occupational injury level compared to a previous study. The study data indicates occurrence of elevated injury levels on farms which expanded and which were intensively managed from a milk production perspective. Farm expansion was associated with increased labor units used and increased investment per hectare. The study also found that use of extension services and farm discussion group participation were not associated with injury occurrence. CONCLUSIONS: This study demonstrates how a retrospective farm workplace occupational injury survey of Irish dairy farms, analysed in combination with farm business data can be used to identify injury risk factors, including those associated with production expansion. Irish dairy farms have a heightened farm workplace occupation injury level while dairy production expansion increased injury levels. Extension engagement did not influence on injury levels. Approaches to improve farm safety on dairy farms are outlined.
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Leite , Traumatismos Ocupacionais , Humanos , Animais , Fazendas , Traumatismos Ocupacionais/epidemiologia , Estudos Retrospectivos , Indústria de Laticínios , Fatores de RiscoRESUMO
An animal's behaviour can influence many variables, such as its energy reserves, its risk of injury or mortality, and its rate of reproduction. To identify the optimal action in a given situation, these various effects can be compared in the common currency of reproductive value. While this idea has been widely used to study trade-offs between pairs of variables, e.g. between energy gain versus survival, here we present a unified framework that makes explicit how these various trade-offs fit together. This unification covers a wide range of biological phenomena, highlighting similarities in their logical structure and helping to identify knowledge gaps. To fill one such gap, we present a new model of foraging under the risk of predation and damage accumulation. We conclude by discussing the use and limitations of state-dependent optimisation theory in predicting biological observations.
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Adaptação Psicológica , Reprodução , Animais , Evolução BiológicaRESUMO
PURPOSE: Farming is a high-pressure occupation. Populations of farmers face significant health risks, including injury, mental illness, and in some cases, heavy alcohol use. However, there is little research on farmers' use of substances beyond alcohol. This study examines factors relating to Irish farmers' disordered alcohol and substance use. METHODS: In accordance with STROBE guidelines for cross-sectional research and reporting, we examined disordered alcohol and substance use in 351 Irish farmers using the Alcohol Use Disorders Identification Tool (AUDIT) and Drug Use Disorders Identification Tool (DUDIT). FINDINGS: While 28% of farmers did not drink, 40% of those who did drink exceeded the AUDIT threshold for disordered use. Similarly, while 95% of farmers did not use substances, 78% of farmers who did use substances exceeded the DUDIT threshold for disordered use. Age was the most important risk factor for disordered alcohol and substance use and correlated with other main risk factors: lower income, no children, part-time farmer, and full-time off-farm roles. Disordered drinking was highest in farmers engaged in full-time education. CONCLUSIONS: This population of Irish farmers report broadly healthy alcohol and substance use behaviors. Irish farmers may serve as a model group whose strengths can be utilized in interventions within and beyond the Irish farming community. Our results confirm the importance of analyzing demographic factors in farmers' drinking and identify younger farmers as especially at-risk for harmful alcohol and substance use.
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Alcoolismo , Transtornos Relacionados ao Uso de Substâncias , Humanos , Fazendeiros , Estudos Transversais , Alcoolismo/epidemiologia , Fazendas , Transtornos Relacionados ao Uso de Substâncias/epidemiologiaRESUMO
Secondary lymphedema occurs in up to 20% of patients after lymphadenectomy performed for the surgical management of tumors involving the breast, prostate, uterus, and skin. Patients develop progressive edema of the affected extremity due to retention of protein-rich lymphatic fluid. Despite compression therapy, patients progress to chronic lymphedema in which noncompressible fibrosis and adipose tissue are deposited within the extremity. The presence of fibrosis led to our hypothesis that rosiglitazone, a PPARγ agonist that inhibits fibrosis, would reduce fibrosis in a mouse model of secondary lymphedema after hind limb lymphadenectomy. In vivo, rosiglitazone reduced fibrosis in the hind limb after lymphadenectomy. Our findings verified that rosiglitazone reestablished the adipogenic features of TGF-ß1-treated mesenchymal cells in vitro. Despite this, rosiglitazone led to a reduction in adipose tissue deposition. Single-cell RNA-Seq data obtained from human tissues and flow cytometric and histological evaluation of mouse tissues demonstrated increased presence of PDGFRα+ cells in lymphedema; human tissue analysis verified these cells have the capacity for adipogenic and fibrogenic differentiation. Upon treatment with rosiglitazone, we noted a reduction in the overall quantity of PDGFRα+ cells and LipidTOX+ cells. Our findings provide a framework for treating secondary lymphedema as a condition of fibrosis and adipose tissue deposition, both of which, paradoxically, can be prevented with a pro-adipogenic agent.
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Linfedema , Receptor alfa de Fator de Crescimento Derivado de Plaquetas , Masculino , Feminino , Humanos , Camundongos , Animais , PPAR gama , Rosiglitazona/farmacologia , Rosiglitazona/uso terapêutico , Linfedema/tratamento farmacológico , FibroseRESUMO
We redescribe a species of fiddler crab, Minuca panema (Coelho, 1972), from the Atlantic coast of South America. It is closely related to M. mordax (Smith, 1870), and until now, the taxon has been considered to be synonymous with another closely related species Minuca burgersi (Holthuis, 1967). However, we found that two clades of M. burgersi sensu lato were restricted to the Caribbean Basin. This distribution differs from than that of M. panema, which occurs primarily along the eastern coast of South America, ranging from the island of Trinidad to Praia da Armação, Santa Catarina, Brazil. Based on our field studies, the geographical boundary between M. burgersi sensu stricto and M. panema is the Tobago Basin, north of Trinidad. Since the two species diverged only 3 to 4 million years ago, as dated from the phylogeny of the genus Minuca Bott 1954, there are few reliable morphological features that can be used to distinguish them clearly. In live crabs, there is a striking difference in coloration between the cherryred South American M. panema and the rusty-red Caribbean M. burgersi sensu lato. In males, the pattern of tubercles on the inner surface of the major cheliped varies between the two species. In females, the vulva is slightly larger in M. burgersi sensu stricto. Ocean tides and currents together with siltation owing to freshwater outflow from the Amazon and Orinoco rivers most likely have driven the divergence of these species. In the Caribbean, small tidal amplitudes have minimized long-distance gene flow in M. burgersi sensu stricto from isolated insular lagoons. In contrast, large tidal amplitudes and exposed habitats on riverbanks along the eastern Atlantic coast of South America have enabled long-distance dispersal in M. panema. DNA analysis reveals that haplotypes of cytochrome c oxidase subunit 1 are not shared between the species. Since natural selection and/or genetic drift have yet to produce extensive morphological divergences between M. panema and M. burgersi sensu stricto, we speculate that changes in the genes regulating mitochondrial DNA functions have led to speciation at the molecular level. According to the mitonuclear compatibility concept, we propose that mitochondrial DNA may be at the forefront of speciation events and that co-evolved mitonuclear interactions are responsible for some of the earliest genetic incompatibilities arising among isolated populations.
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We used the gill (Na+, K+)-ATPase as a molecular marker to provide a comprehensive kinetic analysis of the effects of Co2+in vitro on the modulation of K+-phosphatase activity in the Blue crab Callinectes danae. Co2+ can stimulate or inhibit K+-phosphatase activity. With Mg2+, K+-phosphatase activity is almost completely inhibited by Co2+. Co2+ stimulates K+-phosphatase activity similarly to Mg2+ although with a ≈4.5-fold greater affinity. At saturating Mg2+ concentrations, Mg2+ displaces bound Co2+ from the Mg2+-binding site in a concentration dependent manner, but Co2+ cannot displace Mg2+ from its binding site even at millimolar concentrations. Saturation by Co2+ of the Mg2+ binding site does not affect pNPP recognition by the enzyme. Substitution of Mg2+ by Co2+ slightly increases enzyme affinity for K+ and NH4+. Independently of Mg2+, inhibition by ouabain or sodium ions is unaffected by Co2+. Investigation of gill (Na+, K+)-ATPase K+-phosphatase activity provides a reliable tool to examine the kinetic effects of Co2+ with and without Na+ and ATP. Given that the toxic effects of Co2+ at the molecular level are poorly understood, these findings advance our knowledge of the mechanism of action of Co2+ on the crustacean gill (Na+, K+)-ATPase.
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Braquiúros , Animais , ATPase Trocadora de Sódio-Potássio/metabolismo , Cinética , Cobalto/toxicidade , Brânquias/metabolismo , Íons , Sódio/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/farmacologiaRESUMO
Massive irreparable rotator cuff tears (RCTs) are a commonly encountered orthopedic condition that can be difficult to treat. Several techniques have been described to manage these tears, with the implantable subacromial balloon spacer being one of the most recent. The device, which has only been approved for clinical use in the United States since 2021, functions by resisting the superior humeral head migration seen in the setting of massive RCTs and restoring normal shoulder biomechanics, as corroborated by cadaveric studies. However, results regarding clinical outcomes have been mixed to date, and further high-quality studies are needed to define the optimal use of the subacromial balloon spacer in the treatment of massive irreparable RCTs.
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BACKGROUND: In Ireland, the agriculture sector reports the highest number of fatalities even though farmers constitute only 6% of the working population. Tractor-related behaviours are implicated in 55% of all vehicle work-related fatalities and 25% of reported injuries, and many of these occur in farmyards. There is limited research on the feasibility and acceptability of behaviour change interventions to improve tractor safety. Target behaviours that promote safe operation in farmyards, determining and addressing blind spots of tractors, were identified, and an intervention was developed following the Behaviour Change Wheel Approach. The objective of the study is to examine the feasibility, fidelity and acceptability of a behaviour change intervention to enhance the safe operation of tractors in farmyards with a particular focus on tractor blind spots. METHOD: A single group feasibility study will be undertaken. Approximately 16 farmers from four major farm types will be recruited for the study between August and September 2022. The intervention involves an in-person demo session, facilitated discussion and personalised safety training procedure with safety goals. The study will collect data from participants at three time points: baseline (3-10 days prior to the intervention), during the intervention and at the follow-up session (7-30 days post-intervention). Quantitative data will be collected through a pre-intervention interview and feedback surveys. A pre- and post-intervention qualitative interview will also be conducted with the participants and will be supplemented with qualitative data from recruitment logs, observational memos and logs and feedback from recruiters. Evaluation of the feasibility, acceptability and fidelity of the intervention will be guided by a pre-determined feasibility checklist, fidelity framework and theoretical framework of acceptability, respectively. Interviews will be analysed using the content analysis. DISCUSSION: The current study can determine the feasibility and fidelity of delivering a systematic, theoretically driven, tailored behaviour change intervention. It will also assess whether the intervention, its ingredients and delivery are acceptable to the farming population. This study will also inform the development of a future larger trial to test the effectiveness of the intervention. TRIAL REGISTRATION: ISRCTN Identifier: ISRCTN22219089. Date applied 29 July 2022.
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This investigation examines the kinetic characteristics and effect of acclimation to a brackish medium (21 S) on gill V(H+)-ATPase activity in two hololimnetic populations of M. amazonicum. We also investigate the cellular immunolocalization of the enzyme. Immunofluorescence findings demonstrate that the V(H+)-ATPase c-subunit is distributed in the apical pillar cells of shrimps in fresh water but is absent after acclimation to 21 S for 10 days. V(H+)-ATPase activity from the Tietê River population is ≈50% greater than the Grande River population, comparable to a wild population from the Santa Elisa Reservoir, but is 2-fold less than in cultivated shrimps. V(H+)-ATPase activity in the Tietê and the Grande River shrimps is abolished after 21 S acclimation. The apparent affinities of the V(H+)-ATPase for ATP (0.27 ± 0.04 and 0.16 ± 0.03 mmol L-1, respectively) and Mg2+ (0.28 ± 0.05 and 0.14 ± 0.02 mmol L-1, respectively) are similar in both populations. The absence of V(H+)-ATPase activity in salinity-acclimated shrimps and its apical distribution in shrimps in fresh water underpins the importance of the crustacean V(H+)-ATPase for ion uptake in fresh water.
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Decápodes , Palaemonidae , Animais , Rios , Brânquias/metabolismo , ATPases Translocadoras de Prótons , Decápodes/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Student success in basic medical science courses is typically determined by their individual performance on examinations of various types. Previous research both within and outside medical education has shown that the use of educational assessment activities can increase learning as demonstrated by performance on subsequent examinations, a phenomenon known as the testing effect. Activities primarily designed and used for assessment and evaluation purposes can also be used as teaching opportunities. We developed a method for measuring and evaluating student accomplishment in a preclinical basic science course that incorporates both individual and collaborative efforts, encourages and rewards active participation, does not compromise the reliability of the assessment outcome and is perceived by the students as helpful and valuable. The approach involved a two-part assessment activity composed of an individual examination and a small group examination with each component differentially weighted in determining an overall examination score. We found that the method was successful in encouraging collaborative efforts during the group component and provided valid measures of student grasp of the subject matter. We describe the development and implementation of the method, provide data derived from its use in a preclinical basic science course and discuss factors to be addressed when utilizing this approach to ensure fairness and reliability of the outcome. We include brief summary comments from students regarding their impressions of the value of this method.
Assuntos
Educação Médica , Avaliação Educacional , Humanos , Reprodutibilidade dos Testes , Avaliação Educacional/métodos , Aprendizagem , CurrículoRESUMO
Farming is essential work, but it suffers from very high injury and fatality rates. Machinery, including tractors, are a leading cause of serious injuries and fatalities to farmers and farm workers in many countries. Herein, we document the systematic development of an evidence-based, theory-informed behaviour change intervention to increase machine-related safety on farms. Intervention development progressed through four phases. Phase 1 defined the problem in behavioural terms based a review of the literature, Phase 2 identified candidate intervention targets through a series of focus groups guided by the Capability-Opportunity-Motivation-Behaviour (COM-B) model and Phase 3 employed expert and stakeholder consultation guided by the Behaviour Change Wheel (BCW) to consider potential target behaviours and intervention components and finalise the intervention content. Phase 4 finalised the evaluation strategies with a team of agricultural advisors who supported the rollout and identified outcome measures for the first trial. The target intervention was the identification of blind spots of farm tractors, and three priority target behaviours (farm safety practices) were identified. Following Phase 3, the intervention comprised four components that are delivered in a group-based, face-to-face session with farmers. In Phase 4, the acceptability, feasibility, and fidelity of these components were identified as the outcome measures for the first trial of the intervention. The four-phase systematic method detailed here constitutes an initial template for developing theory-based, stakeholder-driven, behaviour-change-based interventions targeting farmers and reporting such developments.