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1.
Immunity ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39013466

RESUMO

Lassa virus is estimated to cause thousands of human deaths per year, primarily due to spillovers from its natural host, Mastomys rodents. Efforts to create vaccines and antibody therapeutics must account for the evolutionary variability of the Lassa virus's glycoprotein complex (GPC), which mediates viral entry into cells and is the target of neutralizing antibodies. To map the evolutionary space accessible to GPC, we used pseudovirus deep mutational scanning to measure how nearly all GPC amino-acid mutations affected cell entry and antibody neutralization. Our experiments defined functional constraints throughout GPC. We quantified how GPC mutations affected neutralization with a panel of monoclonal antibodies. All antibodies tested were escaped by mutations that existed among natural Lassa virus lineages. Overall, our work describes a biosafety-level-2 method to elucidate the mutational space accessible to GPC and shows how prospective characterization of antigenic variation could aid the design of therapeutics and vaccines.

2.
Conserv Biol ; 38(4): e14261, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38571408

RESUMO

Amid a global infrastructure boom, there is increasing recognition of the ecological impacts of the extraction and consumption of construction minerals, mainly processed as concrete, including significant and expanding threats to global biodiversity. We investigated how high-level national and international biodiversity conservation policies address mining threats, with a special focus on construction minerals. We conducted a review and quantified the degree to which threats from mining these minerals are addressed in biodiversity goals and targets under the 2011-2020 and post-2020 biodiversity strategies, national biodiversity strategies and action plans, and the assessments of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Mining appeared rarely in national targets but more frequently in national strategies. Yet, in most countries, it was superficially addressed. Coverage of aggregates mining was greater than coverage of limestone mining. We outline 8 key components, tailored for a wide range of actors, to effectively mainstream biodiversity conservation into the extractive, infrastructure, and construction sectors. Actions include improving reporting and monitoring systems, enhancing the evidence base around mining impacts on biodiversity, and modifying the behavior of financial agents and businesses. Implementing these measures could pave the way for a more sustainable approach to construction mineral use and safeguard biodiversity.


Amenazas de la minería a las políticas de alto nivel para la conservación de la biodiversidad Resumen Enmedio del auge global del desarrollo de infraestructura, hay un mayor reconocimiento de los impactos ecológicos de la extracción y consumo de materiales para construcción, procesados predominantemente como concreto. Estos materiales representan amenazas significativas y en expansión para la biodiversidad global. Investigamos cómo son abordadas las amenazas de la minería por las políticas nacionales e internacionales de alto nivel para la conservación de la biodiversidad, con enfoque especial en los minerales para construcción. Realizamos una revisión exhaustiva y cuantificamos el grado en el cual son abordadas las amenazas de la extracción de estos minerales en los objetivos y metas para la biodiversidad bajo estrategias 2011­2020 y post 2020, las estrategias y planes de acción nacionales para la biodiversidad, y las evaluaciones de la Plataforma Intergubernamental Científico­normativa sobre Diversidad Biológica y Servicios de los Ecosistemas. La minería raramente apareció en los objetivos nacionales, pero fue más frecuente en las estrategias nacionales. Sin embargo, fue abordada superficialmente en la mayoría de los países. La cobertura de minería de agregados fue mayor que la cobertura de la minería de caliza. Describimos ocho componentes clave, adaptados para una amplia gama de actores, para incorporar eficazmente la conservación de la biodiversidad en los sectores extractivo, desarrollo de infraestructura y construcción. Las acciones incluyen la mejora de los sistemas de informes y monitoreo, el reforzamiento de la base de evidencias en torno a los impactos de la minería sobre la biodiversidad y la modificación del comportamiento de los agentes financieros y comerciales. La implementación de estas medidas podría allanar el camino para un enfoque más sostenible en el uso de minerales para la construcción y la salvaguarda de la biodiversidad.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Política Ambiental , Mineração , Conservação dos Recursos Naturais/métodos , Política Ambiental/legislação & jurisprudência
3.
Insects ; 15(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38535363

RESUMO

We compared the attractiveness of five commercially available Italian macaroni pastas of different shapes (penne, casarecce, and fusilli) made from cereals and/or legumes [100% Triticum durum; 100% Cicer arietinum; 100% Lens esculenta; 50% Triticum durum + 50% Cicer arietinum; 60% Triticum durum + 40% Lens esculenta] to adults of Sitophilus zeamais (L.). A multiple-choice walking bioassay showed that S. zeamais adults were more attracted to cereal than legume pastas. The modified Flit-Track M2 trap devices baited with pasta made with 100% T. durum captured an average of 61.4% of the adults released into the olfactometric arena after 7 days. Of the insects tested, pasta made with 100% C. arietinum trapped 3.8%, pasta made with 100% L. esculenta trapped 2.7%, pasta made with 50% T. durum + 50% C. arietinum trapped 4.3%, and pasta made with 60% T. durum + 40% L. esculenta trapped 4.2%. When individually compared, 79.6% of S. zeamais adults chose the Triticum durum pasta. Orientation to 100% Cicer pasta or 100% Lens pasta was not observed. In the choice test, only 37% and 25% were attracted to Triticum and Cicer pastas or Triticum and Lens pasta, respectively. Our results confirm that the low attractiveness of legume pasta is mainly due to the lack of attractant stimuli rather than the emission of repellent compounds. From a practical perspective, it is also interesting to note how mixed pasta decreases the risk of S. zeamais infestation.

4.
R Soc Open Sci ; 11(3): 231075, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511084

RESUMO

Individual variation in fearfulness can be modified during ontogeny, and high levels of fear can affect animal welfare. We asked whether early-life environmental complexity and genetic strain affect fear behaviour in young laying hens (pullets). Four replicates of brown (B) and white (W) genetic strains (breeds) of layers were each raised in four environmental treatments (housing): conventional cages (Conv) and different rearing aviaries with increasing space and complexity (Low < Mid < High). We used a startle reflex test (weeks 4 and 14) to measure startle amplitude and autonomic response (i.e. comb temperature). A combination of novel arena (NA) and novel object (NO) tests was used (week 14) to assess NA exploration and alertness, latency to approach the centre and initial NO avoidance and investigation. Housing × strain affected startle amplitude (B-Conv, B-High < B-Low, B-Mid; B > W; no housing effect in W) but not autonomic response. Fear behaviour was affected by housing (NA exploration, investigation: Conv < Low, Mid, High; NO avoidance: Conv, High < Low, Mid), strain (NA alertness: B > W, NO avoidance: W > B) and their interaction (NA centre approach: B-Conv < all other groups). We present evidence for strain-specific fear responses depending on early experience.

5.
J Neurosci Res ; 102(2): e25300, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361409

RESUMO

Environment enrichment (EE) is a well-known eustress model showing beneficial effects in different psychiatric diseases, but its positive properties in panic disorders are not yet established. The confrontation between prey and predator in complex arenas has been validated as a putative panic attack model. The principal aim of this work was to investigate the role of the EE on panic-like defensive responses elicited by mice threatened by venomous snakes. After 6 weeks of exposure either to an enriched or standard environments, 36 male mice were habituated in a complex polygonal arena for snakes containing an artificial burrow and elevated platforms for escape. The animals were confronted by Bothrops jararaca for 5 min, and the following antipredatory responses were recorded: defensive attention, stretched attend posture, flat back approach, prey versus predator interaction, oriented escape behavior, time spent in a safe place, and number of crossings. Mice threatened by snakes displayed several antipredatory reactions as compared to the exploratory behavior of those animals submitted to a nonthreatening situation (toy snake) in the same environment. Notably, EE causes anxiolytic- and panicolytic-like effects significantly decreasing the defensive attention and time spent in safe places and significantly increasing both prey versus predator interaction and exploratory behavior. In conclusion, our data demonstrate that EE can alter the processing of fear modulation regarding both anxiety- and panic-like responses in a dangerous condition, significantly modifying the decision-making defensive strategy.


Assuntos
Crotalinae , Transtorno de Pânico , Camundongos , Masculino , Animais , Bothrops jararaca , Medo , Pânico/fisiologia
6.
Zebrafish ; 21(1): 1-14, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38301171

RESUMO

The larval zebrafish is a highly versatile model across research disciplines, and the expanding use of behavioral analysis has contributed to many advances in neuropsychiatric, developmental, and toxicological studies, often through large-scale chemical and genetic screens. In the absence of standardized approaches to larval zebrafish behavior analysis, however, it is critical to understand the impact on behavior of experimental variables such as the size of testing arenas and the choice of embryo medium. Using a custom-built, modular high-throughput testing system, we examined the effects of 4 testing arena sizes and 11 types of embryo media on conserved sensorimotor behaviors in zebrafish larvae. Our data show that testing arena size impacts acoustic startle sensitivity and kinematics, as well as spontaneous locomotion and thigmotaxis, with fish tested in larger arenas displaying reduced startle sensitivity and increased locomotion. We also find that embryo media can dramatically affect startle sensitivity, kinematics, habituation, and prepulse inhibition, as well as spontaneous swimming, turning, and overall activity. Common medium components such as methylene blue and high calcium concentration consistently reduced startle sensitivity and locomotion. To further address how the choice of embryo medium can impact phenotype expression in zebrafish models of disease, we reared chd7 mutant larvae, a model of CHARGE syndrome with previously characterized morphological and behavioral phenotypes, in five different types of media and observed impacts on all phenotypes. By defining the effects of these key extrinsic factors on larval zebrafish behavior, these data can help researchers select the most appropriate conditions for their specific research questions, particularly for genetic and chemical screens.


Assuntos
Locomoção , Peixe-Zebra , Animais , Peixe-Zebra/genética , Larva/fisiologia , Natação , Comportamento Animal
7.
Cell Rep ; 43(2): 113671, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280195

RESUMO

Outside of the laboratory, animals behave in spaces where they can transition between open areas and coverage as they interact with others. Replicating these conditions in the laboratory can be difficult to control and record. This has led to a dominance of relatively simple, static behavioral paradigms that reduce the ethological relevance of behaviors and may alter the engagement of cognitive processes such as planning and decision-making. Therefore, we developed a method for controllable, repeatable interactions with others in a reconfigurable space. Mice navigate a large honeycomb lattice of adjustable obstacles as they interact with an autonomous robot coupled to their actions. We illustrate the system using the robot as a pseudo-predator, delivering airpuffs to the mice. The combination of obstacles and a mobile threat elicits a diverse set of behaviors, such as increased path diversity, peeking, and baiting, providing a method to explore ethologically relevant behaviors in the laboratory.


Assuntos
Robótica , Navegação Espacial , Camundongos , Animais , Robótica/métodos , Roedores
8.
Community Ment Health J ; 60(2): 376-384, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37882893

RESUMO

Arab immigrants constitute a sizable portion of the US population, and their adjustment and relocation challenges might escalate mental health issues. Nevertheless, mental health care accessibility among such populations is not recognized as policy issue. Hence, it is crucial to explore the political tools that might be employed to improve immigrants' access to mental health treatment. The Public Arenas Model (Hilgartner and Bosk, American Journal of Sociology 94:53-78, 1988) provides better understanding of how access to mental health care is defined in the public sphere, why mental health inaccessibility among Arabs has not received attention, and how stakeholders worked to raise the public's attention to such issue (Smith, Policy, Politics & Nursing Practice 10:134-142, 2009). Ultimately, several policy options are proposed to address Arab immigrants' access to mental health care issue, including increasing mental health service providers' language proficiency and cultural competency, integration of behavioral health and primary care services for immigrant populations, and considering novel modes of mental health delivery.


Assuntos
Emigrantes e Imigrantes , Serviços de Saúde Mental , Humanos , Estados Unidos , Árabes/psicologia , Acessibilidade aos Serviços de Saúde , Competência Cultural
9.
Bioinformation ; 19(4): 345-347, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822829

RESUMO

World Health Organization (WHO) Risk Group-4 (RG-4) pathogens are among the most dangerous of the emergent and re-emergent viruses. International health agencies, working in concert, bridge the gaps in health care for populations at risk for RG-4 viral pathogen exposure. RG-4 virus research incorporates Biodefense Program and Biosafety Laboratory (BSL)-4 technologies. RG-4 viruses include Arena-viridae, Filo-viridae, Flavi-viridae, Herpes-viridae, Nairo-viridae, Paramyxo-viridae, and Pox-viridae.

10.
J Equine Vet Sci ; 131: 104934, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37776920

RESUMO

During an African horse sickness (AHS) outbreak, horses were able to exercise daily in a net-covered arena, yet the physiological responses to exercise in a netted arena was unknown. In a cross-over study design, eight horses performed a 39-minute aerobic exercise in conventional (CA) and vector-protected arenas (VPA). Horses were slower in some gaits and covered less distance in the VPA arena (P < .01). Cortisol release, hematology, and heart rate variability (HRV) were also examined. An interaction between the riding arena and time was observed in hematocrit (P = .0013), hemoglobin (P = .0012), and red blood cell count (P = .0027) and HRV variables, including mean beat-to-beat (RR) intervals (P < .0001), mean heart rate (P < .0001), sympathetic nervous system (SNS) index (P = .0038) and parasympathetic nervous system (PNS) index (P < .0001). Cortisol concentrations increased during exercise and 30 minutes postexercise in both arenas. Hematocrit, hemoglobin, and red blood cell count increased immediately postexercise in horses in VPA while remaining high from immediate post-exercise to 60 minutes postexercise in horses in CA. HRV decreased during exercise and was not different between horses in both arenas, but a higher RR interval and PNS index, corresponding to lower heart rate and SNS index, were detected during 30 to 60 minutes postexercise in horses in the VPA compared to the CA. Riding horses in different arenas impacted hematological and HRV variables. The greater RR intervals and PNS index, coinciding with the lower SNS index and heart rate, indicated parasympathetic dominance post-exercise in horses in VPA compared to CA.


Assuntos
Doença Equina Africana , Doenças dos Cavalos , Condicionamento Físico Animal , Cavalos , Animais , Hidrocortisona , Estudos Cross-Over , Hemoglobinas
11.
J Anal Psychol ; 68(4): 665-686, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37565389

RESUMO

This paper examines the symbolism of the cultural image Sun Wukong (the Monkey King), a Chinese legendary hero, and how it influenced an eight-year-old boy's psychic development. Through an analysis of Sun Wukong's life from his birth to attaining Buddhahood, a three-phase healing process is identified in Sun Wukong's tale and the psychotherapeutic process: "naming and initiating," "nurturing and taming," and "transforming and transcending," proposed by Dr. Heyong Shen. Sandplay visually highlighted these key clinical changes in conscious awareness and developmental behaviour influencing the boy's individuation process. Images found either in cultural traditions or spontaneously emerging from the unconscious in individuals are of significance in human life, offering pathways to psychic healing and development. Further, myths and cultural resources used in clinical work demonstrate that having cultural competency is invaluable in Jungian analysis. Pathogenic and health-maintenance factors of culture can be explored in future clinical practice and research.


Cet article étudie le symbolisme de l'image culturelle d'un héros légendaire chinois; Sun Wukong (le roi singe). L'article explore comment cette image a influencé le développement psychique d'un garçon de huit ans. À travers une analyse de la vie de Sun Wukong depuis sa naissance jusqu'à ce qu'il atteigne la bouddhéité, un processus de guérison en trois phases est identifié dans le conte de Sun Wukong et dans le processus psychothérapeutique, et proposé par le Dr Heyong Shen : « nommer et initier ¼, « apprivoiser et nourrir ¼ et « transformer et transcender ¼. La thérapie par le jeu de sable a ensuite mis en évidence visuellement ces changements cliniques clés dans la prise de conscience et le comportement développemental, qui ont influencé le processus d'individuation du garçon. Les images trouvées dans les traditions culturelles ou qui émergent spontanément de l'inconscient chez les individus sont importantes dans la vie des êtres humains : elles fournissent des voies de guérison et de développement psychiques. De plus, les mythes et les ressources culturelles utilisés dans le travail clinique montrent que la compétence culturelle est inestimable dans l'analyse jungienne. Les facteurs pathogènes et les facteurs de maintien de la santé - présents dans la culture - peuvent être explorés dans la pratique clinique et la recherche futures.


Este artículo explora el simbolismo de la imagen cultural de Sun Wukong (el Rey Mono), un héroe legendario chino, y cómo influyó en el desarrollo psíquico de un niño de ocho años. A través de un análisis de la vida de Sun Wukong desde su nacimiento hasta alcanzar la Budeidad, se identifica un proceso de curación en tres fases en el cuento de Sun Wukong y en el proceso psicoterapéutico: "nombrar e iniciar", "domar y nutrir" y "transformar y trascender", propuestos por el Dr. Heyong Shen. A continuación, el juego de arena puso de relieve visualmente estos cambios clínicos en la conciencia y en el desarrollo del comportamiento, influyendo en el proceso de individuación del niño. Las imágenes que se encuentran tanto en las tradiciones culturales, como las que que emergen espontáneamente del inconsciente de los individuos son importantes en la vida humana, ya que ofrecen vías para la curación psíquica y el desarrollo. Además, los mitos y los recursos culturales utilizados en el trabajo clínico demuestran que tener competencia cultural es inestimable en el análisis junguiano. Los factores patógenos y de mantenimiento de la salud de la cultura pueden explorarse en la práctica clínica y la investigación futuras.


Assuntos
População do Leste Asiático , Teoria Junguiana , Masculino , Humanos , Criança , Ludoterapia , Competência Cultural , Individuação
12.
BJPsych Open ; 9(5): e143, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37550867

RESUMO

BACKGROUND: Terrorist incidents lead to a range of mental health outcomes for people affected, sometimes extending years after the event. Secondary stressors can exacerbate them, and social support can provide mitigation and aid recovery. There is a need to better understand distress and mitigating factors among survivors of the Manchester Arena attack in 2017. AIMS: We explored three questions. First, what experiences of distress did participants report? Second, how might secondary stressors have influenced participants' psychosocial recoveries? Third, what part has social support played in the relationships between distress and participants' recovery trajectories? METHOD: We conducted a cross-sectional online survey of a convenience sample of survivors of the Manchester Arena bombing (N = 84) in January 2021 (3 years 8 months post-incident), and a longitudinal study of the same participants' scores on mental health measures over 3 years from September 2017. RESULTS: Survivors' mental well-being scores in early 2021 were significantly lower than general population norms. Longitudinal follow-up provided evidence of enduring distress. Secondary stressors, specifically disruptions to close relationships, were associated with greater post-event distress and slower recovery. We found an indirect relationship between identifying with, and receiving support from, others present at the event and mental well-being >3 years later. CONCLUSIONS: The Arena attack has had an enduring impact on mental health, even in survivors who had a mild response to the event. The quality of close relationships is pivotal to long-term outcome. Constructive support from family and friends, and people with shared experiences, are key to social cure processes that facilitate coping and recovery.

13.
J Dairy Sci ; 106(11): 7698-7710, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37641357

RESUMO

The most suitable light intensity for cows during nighttime has not been thoroughly investigated. Recommendations on the night-time lighting regimen on dairy farms differ between countries and range from light throughout the night to darkness to allow the animals a rest from artificial light. Commercial actors recommend red light for night-time lighting in cattle barns to facilitate livestock supervision with minimum disturbance for the animals. However, little is known about how light intensity, spectrum, and uniformity affect the ability of cows to navigate their indoor environment. Thus, in a change-over study with 12 pregnant, nonlactating dairy cows, we observed how the cows walked through an obstacle course under different light treatments. Obstacles were positioned differently for every run, to present a novel challenge for each light environment. Fourteen different light treatments were tested, involving intensity ranging from <0.01 (darkness) to 4.49 µmol m-2 s-1, high or low uniformity, and white or red color. Light was characterized in terms of illuminance, photon flux density, spectral composition, and uniformity. Additionally, assessment of the environmental light field was used to describe each lighting condition from a bovine and human perspective. Data were analyzed in a generalized mixed model to assess whether lighting conditions affected cow walking speed or stride rate. Pair-wise post hoc comparisons showed that the cows walked at a slower speed in nonuniform red light compared with uniform white light or uniform red light. Interestingly, darkness did not alter walking speed or stride rate. The odds of different behaviors occurring were not affected by lighting conditions. In conclusion, darkness did not affect the ability of cows to navigate through the obstacle course, but medium-intensity, nonuniform red light affected their speed. Hence, cows do not necessarily need night-time lighting to navigate, even in a test arena with obstacles blocking their way, but nonuniform light distribution may have an effect on their movements.

14.
bioRxiv ; 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37577457

RESUMO

The larval zebrafish is a highly versatile model across research disciplines, and the expanding use of behavioral analysis has contributed to many advances in neuro-psychiatric, developmental, and toxicological studies, often through large-scale chemical and genetic screens. In the absence of standardized approaches to larval zebrafish behavior analysis, however, it is critical to understand the impact on behavior of experimental variables such as the size of testing arenas and the choice of embryo medium. Using a custom-built, modular high-throughput testing system, we examined the effects of 4 testing arena sizes and 11 types of embryo media on conserved sensorimotor behaviors in zebrafish larvae. Our data show that testing arena size impacts acoustic startle sensitivity and kinematics as well as spontaneous locomotion and thigmotaxis, with fish tested in larger arenas displaying reduced startle sensitivity and increased locomotion. We also find that embryo media can dramatically affect startle sensitivity, kinematics, habituation, and pre-pulse inhibition, as well as spontaneous swimming, turning, and overall activity. Common media components such as methylene blue and high calcium concentration consistently reduced startle sensitivity and locomotion. To further address how the choice of embryo medium can impact phenotype expression in zebrafish models of disease, we reared chd7 mutant larvae, a model of CHARGE syndrome with previously characterized morphological and behavioral phenotypes, in 5 different types of media and observed impacts on all phenotypes. By defining the effects of these key extrinsic factors on larval zebrafish behavior, these data can help researchers select the most appropriate conditions for their specific research questions, particularly for genetic and chemical screens.

15.
Front Psychol ; 14: 1193172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37397342

RESUMO

Introduction: Toxic behavior (i.e., toxicity) is a pervasive problem in online gaming communities such as League of Legends. This issue arises from factors such as frustrating and stressful in-game experiences and online disinhibition. Prior research on addressing toxicity has focused primarily on the perpetrators and how to mitigate their negative behavior and the consequences. The aim of this study was to approach toxicity from the perspective of the victims instead, and consequently, to investigate the factors that contribute to the experience of victimhood in multiplayer online battle arena games. Methods: A global sample of League of Legends and Defense of the Ancients 2 players (n=313) was collected to test hypotheses based on three theoretical approaches drawn from previous work, namely, the online disinhibition effect, social cognitive theory and theory of planned behavior. Participants were asked to complete a survey that included variables related to the three theoretical approaches. Results: The results of the study indicated that self-efficacy, and benign and toxic disinhibition, were the most relevant antecedents for the experience of being a victim of toxicity. Accordingly, the findings thus suggest that players with low self-efficacy and high online disinhibition may be more likely to experience victimhood in multiplayer online battle arena games. In general, insights based on our study demonstrate that individual characteristics partially explain why some players are more susceptible to toxic behavior than others. Discussion: The study's results have practical implications for game developers and policymakers, particularly in the areas of community management and player education. For example, game developers may consider incorporating self-efficacy training and disinhibition reduction programs into their games. Overall, this study contributes to the growing body of literature on toxicity in online gaming communities and invites further research into toxicity from the perspective of the victims.

16.
Animals (Basel) ; 13(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37443919

RESUMO

During the stance phase of equine locomotion, ground reaction forces are exerted on the hoof, leading first to rapid deceleration ("braking") and later to acceleration ("propulsion") as the hoof leaves the ground. Excessive hoof deceleration has been identified as a risk factor for musculoskeletal injury and may be influenced by arena surface properties. Therefore, our objective was to evaluate the effect of arena surface type (dirt, synthetic) on hoof translation of the leading and trailing forelimbs during jump takeoff and landing. Solar hoof angle, displacement, velocity, and deceleration were captured using kinematic markers and high-speed video for four horses jumping over a 1.1 m oxer at 12 different arenas (5 dirt, 7 synthetic). Surface vertical impact and horizontal shear properties were measured simultaneously. The effects of surface type (dirt, synthetic), jump phase (takeoff, landing), and limb (leading, trailing) on hoof movement were assessed using ANOVA (p < 0.05), while the relationships of hoof movement with surface mechanical properties were examined with correlation. Slide time (p = 0.032), horizontal velocity of the hoof (p < 0.001), and deceleration (p < 0.001) were greater in the leading limb, suggesting a higher risk of injury to the leading limb when braking. However, surface type and jump phase did not significantly affect deceleration during braking.

17.
J Fish Biol ; 103(5): 974-984, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37386747

RESUMO

Although studies on fish cognition are increasing, consideration of how methodological details influence the ability to detect and measure performance is lagging. Here, in two separate experiments the authors compared latency to leave the start position, latency to make a decision, levels of participation and success rates (whether fish entered the rewarded chamber as first choice) across different physical designs. Experiments compared fish performance across (a) two sizes of T-mazes, large and standard, and a plus-maze, and (b) open choice arenas with either two or four doors. Fish in T-mazes with longer arms took longer to leave the start chamber and were less likely to participate in a trial than fish in T-mazes with shorter arms. The number of options, or complexity, in a maze significantly impacted success but did not necessarily impact behavioural measures, and did not impact the number of fish that reached a chamber. Fish in the plus-maze had similar latencies to leave the start box and time to reach any chamber as fish in the same-sized T-maze but exhibited lower overall success. Similarly, in an open choice arena, increasing the number of options - doors to potential reward chambers - resulted in lower probability of success. There was an influence of reward position in the choice arena, with rewarded chambers closest to the sides of the arena resulting in lower latencies to enter and higher probability of decision success. Together the results allow the authors to offer practical suggestions towards optimal maze design for studies of fish cognition.


Assuntos
Cognição , Peixes , Animais , Aprendizagem em Labirinto
18.
Vet J ; 293: 105955, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36781018

RESUMO

Mechanical properties of arena surfaces are extrinsic factors for musculoskeletal injury. Vertical impact forces of harrowed and compacted cushion were measured at five locations on 12 arena surfaces (five dirt, seven synthetic [dirt and fiber]). Eight variables related to impact force, displacement, and acceleration were calculated. Surface temperature, cushion depth and moisture content were also measured. The effects of surface material type (dirt/synthetic) and cushion compaction (harrowed/compacted) on vertical impact properties were assessed using an analysis of variance. Relationships of manageable surface properties with vertical impact forces were examined through correlations. Compacted cushion exhibited markedly higher vertical impact force and deceleration with lower vertical displacement than harrowed cushion (P < 0.001), and the effect was greater on dirt than synthetic surfaces (P = 0.039). Vertical displacement (P = 0.021) and soil rebound (P = 0.005) were the only variables affected by surface type. Surface compaction (harrowed, compacted) had a significantly greater effect on vertical impact forces than surface type (dirt, synthetic). By reducing surface compaction through harrowing, extrinsic factors related to musculoskeletal injury risk are reduced. These benefits were more pronounced on dirt than synthetic surfaces. These results indicate that arena owners should regularly harrow surfaces, particularly dirt surfaces.


Assuntos
Corrida , Animais , Propriedades de Superfície
19.
Vet J ; 291: 105930, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36427603

RESUMO

Shear forces at the surface-hoof interface affect hoof slide, surface grip, forces transferred to the limb, and injury risk. However, the variation in shear forces among surfaces with different compositions have not been quantified. Shear ground reaction forces were measured on five dirt and seven synthetic arena surfaces. Cohesion/adhesion and angle of internal friction/coefficient of friction were calculated. Surface composition, surface temperature, cushion depth, and moisture content were also measured. The effects of surface material (dirt/synthetic) on shear properties were assessed using analysis of variance (ANOVA; P < 0.05). The relationships between surface composition or management properties and shear properties were analyzed using linear correlation. Shear properties were not different between dirt and synthetic surface categories; however, surface fiber content was correlated with adhesion and coefficient of friction. These correlations predict that more fiber will decrease soil adhesion (r = -0.75; P < 0.01) and increase the coefficient of friction (r = 0.81; P < 0.01). Furthermore, maximum shear force was significantly correlated with cushion depth (r = 0.61; P < 0.01) and moisture content (r = 0.57; P < 0.01), where shear force was greater on surfaces with thicker cushion layers or higher moisture content. The findings suggest that shear mechanical behavior is more dependent on surface composition than surface material categories (dirt/synthetic) and also indicate that arena owners can influence shear forces by adjusting either surface composition or management.


Assuntos
Casco e Garras , Cavalos , Animais , Propriedades de Superfície , Resistência ao Cisalhamento
20.
Chinese Journal of Neurology ; (12): 666-672, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-994879

RESUMO

Objective:To investigate the feasibility of blue velvet arena test (BVAT) in evaluating spatial memory function in patients with chronic insomnia disorder (CID).Methods:From June 1, 2021 to May 31, 2022, 62 CID outpatients or inpatients were enrolled continuously in the Department of Sleep Disorders, the Affiliated Chaohu Hospital of Anhui Medical University, and 56 good sleepers in the same period were enrolled to serve as controls. Pittsburgh Sleep Quality Index (PSQI) was used to assess their sleep quality. Montreal Cognitive Assessment Scale (MoCA), nine box maze test (NBMT), and BVAT were used to assess general cognition and memories.Results:Compared to the controls, the CID patients had increased PSQI score [15.0 (12.8, 16.0) vs 0 (0, 1.0); Z=-9.47, P<0.001], and decreased MoCA score [24.5 (21.5, 27.0) vs 27.0 (26.0, 28.0); Z=-4.18, P<0.001]; increased numbers of errors in the spatial working [1.0 (0.8, 2.0) vs 1.0 (0, 1.0); Z=-2.24, P<0.05], object working [1.5 (0.8, 3.0) vs 0 (0, 1.0); Z=-4.36, P<0.001] and object recognition [0 (0, 0) vs 0 (0, 0); Z=-2.10, P<0.05] memories in NBMT; and increased average erroring distance in BVAT [23.0 (16.4, 27.2) cm vs 18.7 (16.6, 20.7) cm; Z=-3.30, P<0.01]. Partial correlation analysis showed that in the CID patients, the average erroring distance in BVAT was positively correlated with erroneous numbers in spatial working memory in NBMT ( r=0.54, P<0.001). Principal components analysis showed that the average erroring distance of BVAT (load=0.844) and the errors of spatial working memory in NBMT (load=0.801) were jointly attributed to the first factor. Receiver operating characteristic curve analysis showed that the sensitivity of BVAT was higher than that of NBMT (0.575 vs 0.250, P<0.05) for spatial memory detection in total sample. Conclusion:The BVAT has a higher reliability in the functional assessment of spatial memory in CID patients.

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