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1.
Trends Ecol Evol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003192

RESUMO

Life history strategies, which combine schedules of survival, development, and reproduction, shape how natural selection acts on species' heritable traits and organismal fitness. Comparative analyses have historically ranked life histories along a fast-slow continuum, describing a negative association between time allocation to reproduction and development versus survival. However, higher-quality, more representative data and analyses have revealed that life history variation cannot be fully accounted for by this single continuum. Moreover, studies often do not test predictions from existing theories and instead operate as exploratory exercises. To move forward, we offer three recommendations for future investigations: standardizing life history traits, overcoming taxonomic siloes, and using theory to move from describing to understanding life history variation across the Tree of Life.

2.
Anim Behav ; 213: 11-21, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007109

RESUMO

Because senescence impairs the ability of older males to compete successfully for mates, male reproductive strategies are expected to change with age. The terminal investment hypothesis proposes that older males, who could die soon, should take greater risks to obtain mating opportunities. Another possibility is that older males avoid such risks, adopting alternative reproductive tactics, such as increased affiliation with females, increased reliance on coalitions or sexual coercion to continue to compete with younger animals. We tested these hypotheses in wild chimpanzees, Pan troglodytes schweinfurthii, of the Kanyawara community, Kibale National Park, Uganda, where old males sire offspring at relatively high rates. Our data set included >40 000 incidents of male aggression and >5800 copulations observed between 2005 and 2017. We found that, even as their dominance status declined, old males maintained relatively high copulation rates, especially with established mothers. There was no evidence for terminal investment in response to ageing. Males became generally less aggressive as they aged. Neither did old males form affiliative bonds with females, nor use sexual coercion more frequently, as alternative reproductive tactics. Old males did, however, participate in coalitionary aggression at higher rates than young males and increased the proportion of their aggression that was coalitionary over time. Coalitions were positively associated with mating success, particularly for low- and middle-ranking males. These results support the hypothesis that ageing male chimpanzees use coalitions as an alternative reproductive tactic. The lack of evidence for terminal investment in response to ageing appears to reflect a broader mammalian pattern in which males who rely on fighting to secure mating opportunities avoid excessive risk taking as their formidability wanes.

3.
Curr Atheroscler Rep ; 26(8): 367-381, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38829515

RESUMO

PURPOSE OF REVIEW: To summarize selected late-breaking science on cardiovascular (CV) disease prevention presented at the 2024 Scientific Session of the American College of Cardiology (ACC) conference. RECENT FINDINGS: The LIBerate-HR trial showed the efficacy and safety of lerodalcibep, a subcutaneous injection that prevents binding of Pro-Protein Convertase Subtilisin/Kexin (PCSK) 9 to low-density lipoprotein (LDL)-receptors resulting in LDL-cholesterol (LDL-C) lowering in patients at very high risk or high risk of atherosclerotic CV disease (ASCVD). The AEGIS-II randomized patients with type 1 myocardial infarction (MI) with multivessel coronary artery disease and additional CV risk factors and found no benefit in major adverse CV events (MACE) with CSL112, an apolipoprotein A1 infusion shown to increase cholesterol efflux capacity. The Bridge-TIMI 73a trial showed a significant reduction in triglyceride (TG) levels with olezarsen, an antisense mRNA, in patients with moderate hyperTG with elevated CV risk. The BE ACTIVE trial showed significant improvement in step counts in patients given behavioral and financial incentives. The DRIVE study showed a significant increase in the prescription of either sodium-glucose co-transporter-2 inhibitors or glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes mellitus (T2DM) at elevated CV or renal risk with a remote team-based, non-licensed navigator and clinical pharmacist approach. The TACTiC trial showed increased and sustained use of statin therapy by patient-driven use of a web-based portal that calculated the ASCVD risk score and gave prompts. The VICTORIAN-INITIATE trial showed efficacy and safety in early use of inclisiran in patients with ASCVD who did not reach target LDL-C < 70 mg/dL despite maximally tolerated statin therapy. The ARISE-HF trial showed no difference in change of peak oxygen consumption with the use of an oral aldose reductase inhibitor, AT-001, in patients with well-controlled T2DM and diabetic cardiomyopathy with high-risk features compared to placebo. The PREVENT trial showed a significant reduction in target vessel failure at 2 years in patients with non-flow limiting vulnerable plaques with percutaneous coronary intervention and optimal medical therapy (OMT) compared to OMT alone. The late-breaking clinical science presented at the 2024 Scientific Session of the ACC paves the way for an evidence-based alternative to statin therapy and provides data on several common clinical scenarios encountered in daily practice.


Assuntos
Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/prevenção & controle , Cardiologia , Estados Unidos/epidemiologia , Congressos como Assunto , Fatores de Risco de Doenças Cardíacas
4.
J Anim Ecol ; 93(7): 849-861, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38751173

RESUMO

Understanding the maintenance and dynamics of phenotypic polymorphisms requires unpicking key ecological mechanisms shaping the fitness costs and benefits of expressing alternative phenotypes, generating selection. Seasonal migration versus year-round residence expressed in partially migratory populations represents one common polymorphism that can experience strong selection through differential reproductive success. Yet, key hypothesised pathways that could generate such selection remain to be empirically tested. One hypothesis is that migratory tactics affect subsequent reproductive success through carry-over effects on breeding site retention and resulting breeding dispersal. By remaining in breeding areas all year round, residents could retain their preferred breeding site between years, and consequently have higher reproductive success. Conversely, migrants that escape harsh non-breeding season conditions could return in better condition, with high resource holding potential, and outcompete residents to retain their site. Such effects could further depend on migration timing and vary between years. Yet, such pathways have not been quantified, precluding empirical parameterisation of partial migration theory. We used 4 years of breeding and non-breeding season data from partially migratory European shags (Gulosus aristotelis) to test whether the three most frequent migratory tactics in this population (full resident, early migrant departing soon after breeding, and late migrant departing in late autumn) differed in their breeding site retention; whether site retention predicted reproductive success; and hence whether effects of migratory tactic on reproductive success were explicable through site retention. Overall, residents were much more likely to retain their breeding site between years than both early and late migrants, and site retention was associated with increased reproductive success. Yet, these effects varied somewhat among years: late migrants were always least likely to retain their site but had variable relative reproductive success. Path analyses revealed that effects of migratory tactic on reproductive success were only partly attributable to breeding site retention. These results indicate that multiple mechanisms underlie reproductive selection on migratory tactics, potentially contributing to maintaining behavioural polymorphisms. Yet, the clear associations between migratory tactics and local breeding dispersal reveal that these movements can be strongly interlinked across seasons, shaping overall spatioseasonal dynamics in partially migratory systems.


Assuntos
Migração Animal , Reprodução , Estações do Ano , Animais , Feminino , Masculino , Charadriiformes/fisiologia , Charadriiformes/genética
5.
BMC Med Educ ; 24(1): 564, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783229

RESUMO

BACKGROUND: Health Data Science (HDS) is a novel interdisciplinary field that integrates biological, clinical, and computational sciences with the aim of analysing clinical and biological data through the utilisation of computational methods. Training healthcare specialists who are knowledgeable in both health and data sciences is highly required, important, and challenging. Therefore, it is essential to analyse students' learning experiences through artificial intelligence techniques in order to provide both teachers and learners with insights about effective learning strategies and to improve existing HDS course designs. METHODS: We applied artificial intelligence methods to uncover learning tactics and strategies employed by students in an HDS massive open online course with over 3,000 students enrolled. We also used statistical tests to explore students' engagement with different resources (such as reading materials and lecture videos) and their level of engagement with various HDS topics. RESULTS: We found that students in HDS employed four learning tactics, such as actively connecting new information to their prior knowledge, taking assessments and practising programming to evaluate their understanding, collaborating with their classmates, and repeating information to memorise. Based on the employed tactics, we also found three types of learning strategies, including low engagement (Surface learners), moderate engagement (Strategic learners), and high engagement (Deep learners), which are in line with well-known educational theories. The results indicate that successful students allocate more time to practical topics, such as projects and discussions, make connections among concepts, and employ peer learning. CONCLUSIONS: We applied artificial intelligence techniques to provide new insights into HDS education. Based on the findings, we provide pedagogical suggestions not only for course designers but also for teachers and learners that have the potential to improve the learning experience of HDS students.


Assuntos
Inteligência Artificial , Ciência de Dados , Humanos , Ciência de Dados/educação , Currículo , Aprendizagem
6.
J Colloid Interface Sci ; 659: 330-338, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38176242

RESUMO

Oxygen evolution reaction (OER) is a crucial half-reaction in water splitting, generating hydrogen for sustainable development, but it is often subject to sluggish kinetics. Abundant transition metal-based OER electrocatalysts have been utilized to expedite the process. However, traditional amorphous catalysts suffer from low conductivity, while the activity of crystalline catalysts is also unsatisfactory. Herein, an amorphous/crystalline heterostructured Co-based hydroxide/tungstate was meticulously constructed and further tailored using a NiFe codoping method (NiFeCoW). Following NiFe codoping, the electronic structure had been modulated, subsequently altering the adsorption toward intermediates. From the electrochemical measurements, the NiFeCoW catalyst demonstrated superior electrocatalytic activity for OER in alkaline media, with a minimal overpotential of 297 mV at 10 mA cm-2 and a cell voltage of 1.57 V for water splitting. This study provides valuable guidance for regulating the amorphous/crystalline heterophase in catalysts through bimetallic modulating engineering.

7.
Behav Ecol Sociobiol ; 78(1): 6, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38187116

RESUMO

Over their lifetime, individuals may use different behavioural strategies to maximize their fitness. Some behavioural traits may be consistent among individuals over time (i.e., 'personality' traits) resulting in an individual behavioural phenotype with different associated costs and benefits. Understanding how behavioural traits are linked to lifetime fitness requires tracking individuals over their lifetime. Here, we leverage a long-term study on a multi-year living species (maximum lifespan ~ 10 years) to examine how docility (an individual's reaction to trapping and handling) may contribute to how males are able to maximize their lifetime fitness. Cape ground squirrels are burrowing mammals that live in social groups, and although males lack physical aggression and territoriality, they vary in docility. Males face high predation risk and high reproductive competition and employ either of two reproductive tactics ('natal' or 'band') which are not associated with different docility personalities. We found that although more docile individuals sired more offspring on an annual basis, docility did not affect an individual's long-term (lifetime) reproductive output. Survival was not associated with docility or body condition, but annual survival was influenced by rainfall. Our findings suggest that although docility may represent a behavioural strategy to maximize fitness by possibly playing a role in female-male associations or female mate-choice, variations in docility within our study population is likely maintained by other environmental drivers. However, individual variations in behaviours may still contribute as part of the 'tool kit' individuals use to maximize their lifetime fitness. Supplementary Information: The online version contains supplementary material available at 10.1007/s00265-023-03421-8.

8.
Bioorg Chem ; 143: 106988, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37995644

RESUMO

For the horseshoe tactic to succeed in inhibiting c-Met and Pim-1, the nicotinonitrile derivatives (2a-n) were produced in high quantities by coupling acetyl phenylpyrazole (1) with the proper aldehydes and ethyl cyanoacetate under basic conditions. Consistent basic and spectroscopic data (NMR, IR, Mass, and HPLC) supported the new products' structural findings. With IC50 potency in nanomolar ranges, these compounds had effectively repressed them, particularly compounds 2d and 2 h, with IC50 values below 200 nM. The most potent compounds (2d and 2 h) were tested for their antitumor effects against prostate (PC-3), colon (HCT-116), and breast (MDA-MB-231) and were evaluated in comparison to the anticancer drug tivantinib using the MTT assay. Similar to tivantinib, these compounds showed good antiproliferative properties against the HCT-116 tumor cells while having low cytotoxicity towards healthy fetal colon (FHC) cells. In the HCT-116 cell line, their ability to trigger the apoptotic cascade was also investigated by looking at the level of Bax and Bcl-2 as well as the activation of the proteolytic caspase cascade. When HCT-116 cells were exposed to compounds 2d and 2 h in comparison to the control, active caspase-3 levels increased. The HCT-116 cell line also upregulated Bcl-2 protein levels and downregulated Bax levels. Additionally, when treated with compound 2d, the HCT-116 cell cycle was primarily stopped at the S phase. Compared to the control, compound 2d treatment significantly inhibited the protein expression levels of c-Met and Pim-1 kinases in the treated HCT-116 cells. Thorough molecular modeling analyses, such as molecular docking and dynamic simulation, were performed to ascertain the binding mechanism and stability of the target compounds.


Assuntos
Antineoplásicos , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , Proteína X Associada a bcl-2 , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/química , Proliferação de Células , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases , Apoptose
9.
J Colloid Interface Sci ; 656: 545-555, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38011773

RESUMO

The ingenious architectural structural engineering is extensively identified as a cogent means for facilitating the electrochemical properties of conversion-type anode materials for sodium-ion storage. Herein, a delicate, scalable and controllable solvent-free strategy is proposed to synthesize ultrafine Mn2O3 quantum dots embedded into N-doped carbon to generate two-dimensional (2D) composites (MNC) with robust interfacial heterostructural interactions for high sodium ion storage and fast reaction kinetics, which averts the use of solvents and environmental pollution, greatly reduces time and production costs. The introduction of metallic Mn species simultaneously achieves the construction of ultrafine Mn2O3 quantum dots and strong interfacial heterostructural COMn bonds between metal species and 2D N-doped carbon matrix. The synergistic effect of the formation of oxide quantum dots, the combination of 2D N-doped carbon and the construction of robust interfacial interactions provides the stable electrode structure, fast reaction kinetics and high electrochemical storage capability of anode materials. Hence, MNC composites in SIBs convey remarkable reversible rate capability. Its superior capacity reaches 215 mAh g-1 for 50 cycles at 0.2 A g-1 and 155 mAh g-1 for 1000 cycles at a high current density of 5 A g-1, which shows good long-term stability. The assembled sodium-ion hybrid capacitors (SIHCs) device delivers outstanding energy density of 138 Wh kg-1 at a power density of 126 W kg-1 and 98% capacity retention after 2000 cycles at 2 A g-1, and tremendous capability for practical applications (69 LEDs can be easily lighted). This work not merely offers guidance for the rational interfacial engineering design of high-capacity Mn-based electrode materials in a feasible and scalable solvent-free tactics for Na+ storage, but also broadens the routes for projecting a better electrode material for other battery systems.

10.
J Anim Ecol ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38156548

RESUMO

Behavioural plasticity is a major driver in the early stages of adaptation, but its effects in mediating evolution remain elusive because behavioural plasticity itself can evolve. In this study, we investigated how male Trinidadian guppies (Poecilia reticulata) adapted to different predation regimes diverged in behavioural plasticity of their mating tactic. We reared F2 juveniles of high- or low-predation population origins with different combinations of social and predator cues and assayed their mating behaviour upon sexual maturity. High-predation males learned their mating tactic from conspecific adults as juveniles, while low-predation males did not. High-predation males increased courtship when exposed to chemical predator cues during development; low-predation males decreased courtship in response to immediate chemical predator cues, but only when they were not exposed to such cues during development. Behavioural changes induced by predator cues were associated with developmental plasticity in brain morphology, but changes acquired through social learning were not. We thus show that guppy populations diverged in their response to social and ecological cues during development, and correlational evidence suggests that different cues can shape the same behaviour via different neural mechanisms. Our study demonstrates that behavioural plasticity, both environmentally induced and socially learnt, evolves rapidly and shapes adaptation when organisms colonize ecologically divergent habitats.


La plasticidad conductual es un factor importante en las primeras fases de adaptación, pero se conocen poco sus efectos sobre la evolución porque la plasticidad conductual en sí puede evolucionar. En este estudio, investigamos cómo los machos del guppy de Trinidad (Poecilia reticulata) adaptados a regímenes de depredación diferentes, han divergido en la plasticidad de su táctica de apareamiento. Criamos juveniles provenientes de poblaciones de alta y baja depredación hasta segunda generación (F2) bajo diferentes combinaciones de señales sociales y de depredación, y evaluamos su comportamiento de apareamiento al llegar a la madurez sexual. Los machos de alta depredación aprendieron su táctica de apareamiento de sus conespecíficos adultos, mientras que los machos de baja depredación no. Los machos de alta depredación aumentaron su cortejo al ser expuestos a señales de depredadores durante su desarrollo; mientras que los machos de baja depredación redujeron su cortejo en respuesta a señales inmediatas de depredadores, pero tan solo cuando no fueron expuestos a tales señales durante el desarrollo. Los cambios conductuales observados inducidos por las señales de depredación están asociados con una plasticidad en el desarrollo de la morfología cerebral, pero los cambios adquiridos por aprendizaje social no. En conclusión, demostramos que las poblaciones de guppy han divergido en su respuesta a señales sociales y ecológicas durante su desarrollo, y mostramos evidencia correlativa que sugiere que diferentes tipos de señales pueden influenciar el mismo comportamiento via mecanismos neuronales diferentes. Nuestro estudio muestra que la plasticidad conductual, tanto inducida por el medio ambiente combo aprendida socialmente, evoluciona rápidamente e influencia la adaptación durante la colonización de hábitats ecológicamente divergentes.

11.
Animals (Basel) ; 13(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38003140

RESUMO

Investigation on food allocation among nestlings of altricial birds is crucial in understanding parent-offspring conflicts within avian families. However, there is no consensus in empirical studies regarding whether parents or offspring determine the food allocation pattern within a brood. In the Plain Laughingthrush (Garrulax davidi), we examine the relationship between parental feeding strategies and nestling begging behaviors. Due to hatching asynchrony, larger nestlings have a competitive advantage in food acquisition over their smaller brood-mates; nevertheless, if the initial food-receivers were already satiated and did not immediately consume the food, parents would retrieve the food and re-allocate it to another nestling. This re-feeding tactic employed by parents reduced the likelihood of early-hatched nestlings monopolizing the food solely due to their larger body size. Our findings indicate that parents primarily allocated food based on nestling begging intensity, while their re-feeding tactic is determined by whether the first food-receivers have consumed the food. To date, our research demonstrates that while parental food allocation primarily hinges on the begging intensity of the nestlings, the decision to re-feed is contingent upon whether the initial recipients of the food ingest it immediately.

12.
BMC Sports Sci Med Rehabil ; 15(1): 132, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833812

RESUMO

This paper aims to evaluate the contribution quality of table tennis matches comprehensively and explore the ranking characteristics of evaluation results and the rationality of grading. Through the application of the documentation method, videos, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Rank Sum Ratio (RSR), the contribution quality evaluation index system of table tennis matches was established. After then, the technical and tactical performances of 38 matches between H (anonymous), who is currently highly concerned and active in the international table tennis world from 2018 to 2020 were comprehensively evaluated. According to research results, H had 8 matches with the Ci value > 0.5 in serve rounds, 4 with the Ci value > 0.5 in receive rounds, and 5 with the RSR value > 0.6 in the comprehensive strength. These findings were generally consistent with the final match results. Furthermore, Pearson Correlation showed that the three indicators were significantly correlated with competition performance (CP) (P < 0.01). Each race could be divided into four grades, and there was a very significant difference among them by variance test (F = 60.281, P < 0.01). Meanwhile, SNK pairwise comparison between four grades had statistical significance (P < 0.05). Therefore, researchers could conclude that the combination of TOPSIS and RSR could objectively and accurately reflect the contribution quality of table tennis matches. This method could be promoted and applied in the competition performance evaluation of other net games.

13.
Assessment ; : 10731911231196483, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37732644

RESUMO

An accurate assessment of intimate partner violence (IPV) is crucial to guide public policy and intervention. The Conflict Tactic Scales Revised (CTS-2) is one of the most widely used instruments to do so. Despite its good psychometric properties, research on interpartner agreement has pointed to low-to-moderate estimates, which generated some concerns about the validity of the results obtained through single-partner reports. This cross-sectional study introduces indexes that have not previously been used to assess interpartner agreement. Both partners' reports on perpetration and victimization were analyzed in a community sample of 268 different-sex couples. Our results generally pointed to better agreement levels on IPV occurrence than frequency, suggesting that the proxy method (i.e., using a single-partner report) could be a reliable method for assessing IPV occurrence but not its frequency in this population. Findings are discussed as well as the advantages and constraints of different IPV assessment practices.

14.
Behav Ecol ; 34(4): 613-620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434639

RESUMO

Intraspecific weapon polymorphisms that arise via conditional thresholds may be affected by juvenile experience such as predator encounters, yet this idea has rarely been tested. The New Zealand harvestman Forsteropsalis pureora has three male morphs: majors (alphas and betas) are large-bodied with large chelicerae used in male-male contests, while minors (gammas) are small-bodied with small chelicerae and scramble to find mates. Individuals use leg autotomy to escape predators and there is no regeneration of the missing leg. Here, we tested whether juvenile experience affects adult morph using leg autotomy scars as a proxy of predator encounters. Juvenile males that lost at least one leg (with either locomotory or sensory function) had a 45 times higher probability of becoming a minor morph at adulthood than intact juvenile males. Leg loss during development may affect foraging, locomotion, and/or physiology, potentially linking a juvenile's predator encounters to their final adult morph and future reproductive tactic.

15.
Glob Chang Biol ; 29(16): 4496-4510, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37259883

RESUMO

Understanding the density-dependent processes that drive population demography in a changing world is critical in ecology, yet measuring performance-density relationships in long-lived mammalian species demands long-term data, limiting scientists' ability to observe such mechanisms. We tested performance-density relationships for an opportunistic omnivore, grizzly bears (Ursus arctos, Linnaeus, 1758) in the Greater Yellowstone Ecosystem, with estimates of body composition (lean body mass and percent body fat) serving as indicators of individual performance over two decades (2000-2020) during which time pronounced environmental changes have occurred. Several high-calorie foods for grizzly bears have mostly declined in recent decades (e.g., whitebark pine [Pinus albicaulis, Engelm, 1863]), while increasing human impacts from recreation, development, and long-term shifts in temperatures and precipitation are altering the ecosystem. We hypothesized that individual lean body mass declines as population density increases (H1), and that this effect would be more pronounced among growing individuals (H2). We also hypothesized that omnivory helps grizzly bears buffer energy intake from changing foods, with body fat levels being independent from population density and environmental changes (H3). Our analyses showed that individual lean body mass was negatively related to population density, particularly among growing-age females, supporting H1 and partially H2. In contrast, population density or sex had little effect on body fat levels and rate of accumulation, indicating that sufficient food resources were available on the landscape to accommodate successful use of shifting food sources, supporting H3. Our results offer important insights into ecological feedback mechanisms driving individual performances within a population undergoing demographic and ecosystem-level changes. However, synergistic effects of continued climate change and increased human impacts could lead to more extreme changes in food availability and affect observed population resilience mechanisms. Our findings underscore the importance of long-term studies in protected areas when investigating complex ecological relationships in an increasingly anthropogenic world.


Assuntos
Ecossistema , Ursidae , Animais , Feminino , Humanos , Composição Corporal , Alimentos , Densidade Demográfica
16.
J Fish Biol ; 103(5): 884-896, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37349978

RESUMO

Alternative migratory tactics in salmonids reflect the large observed interindividual variation in spatial behaviour which may range from strict freshwater residency to uninterrupted anadromy. In Salvelinus, sea migrations are performed during the ice-free period as freshwater overwintering is thought to be obligatory due to physiological constraints. As a result, individuals can either migrate the next spring or remain in freshwater, as anadromy is generally considered facultative. In Arctic charr (Salvelinus alpinus), skipped migrations are known to occur, but limited data are available regarding their frequencies within and among populations. Here, the authors used an otolith microchemistry approach relying on strontium (88 Sr) to infer movements between freshwater and marine habitats, and annual oscillations in zinc (64 Zn) to help with age identification. They determined the age-at-first-migration and the occurrence of subsequent annual migrations in two Nunavik Arctic charr populations sampled in Deception Bay (Salluit) and river systems linked to Hopes Advance Bay (Aupaluk), northern Québec, Canada. The mode for age-at-first-migration was 4+ for both populations, although it exhibited large variation (range: 0+ to 8+). Skipped migrations constituted a rare event, as 97.7% and 95.6% of the examined Arctic charr at Salluit (n = 43, mean age = 10.3 ± 2.0 years) and Aupaluk (n = 45, mean age = 6.0 ± 1.9 years), respectively, were found to have performed uninterrupted annual migrations after initiation of the behaviour. The consistency of the annual migrations suggests that the tactic is sufficiently fitness rewarding to be maintained under current environmental conditions. From a fisheries management perspective, these repeated migrations combined with low site fidelity in this species may lead to large interannual variations in abundance at the local scale, which may represent a challenge for monitoring Arctic charr demographics on a river-by-river basis.


Assuntos
Água Doce , Membrana dos Otólitos , Humanos , Animais , Canadá , Quebeque , Truta/fisiologia
17.
Ethology ; 129(1): 55-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37063455

RESUMO

Male spotted bowerbirds (Ptilonorhynchus maculatus) build and defend a structure of sticks and straw-the bower-decorated with colourful objects to attract mates during the breeding season. Specific non-territorial, subordinate males are tolerated by resident males at bowers over multiple breeding seasons. Prior research showed that these male-male associations exhibit attributes of coalitionary behaviour and that subordinate males gain delayed benefits from associating with bower owners, namely future bower inheritance. Yet, it remained unclear whether subordinate males may additionally gain direct fitness benefits from attending established bowers. Here, we report on four separate instances of sneaky copulations (or attempts of copulating) by subordinate males at resident males' bowers. Multiple non-resident males disrupted the ongoing copulations between the bower owner and a receptive female, and these events were followed by violent aggressive interactions. These observations shed new light on same-sex social dynamics in spotted bowerbirds and support the hypothesis that subordinate males are sexually mature individuals that occasionally obtain access to females while attending established bowers. We discuss these findings in light of the literature on male courtship coalitions and agonistic behaviour in bowerbirds, and highlight further aspects of subordinate behaviour that require empirical investigation.

18.
Biosens Bioelectron ; 232: 115286, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37079991

RESUMO

The state-of-art signal transduction mechanism of anodic photoelectrochemistry is constrained to the hole oxidation reaction, which greatly hinders its application for prospective biosensing applications. Herein, we present an innovative strategy for signal transduction by exploiting the in situ formation of surface oxygen vacancies (VOs) on Fe2O3 nanorods (NRs) through the self-coordination of 2,3-dihydroxynaphthalene (2,3-DHN) on their surfaces. The 2,3-DHN was connected with Fe(Ⅲ) on the surface of Fe2O3 NRs vis the formation of the five-membered ring structures accompanied by the generation of VOs. And the generated VOs introduced a new defect energy level for trapping the photogenerated holes, which enhanced the charge separation and realized the enhancement of photocurrent signal. The developed signal transduction strategy was validated by the first photoelectrochemical (PEC) sensing platform for ß-glucoside (ß-Glu) and lipase (LPS), which can catalyze the hydrolysis of 3-hydroxy-2-naphthalenyl-ß-D-glucoside and naphthalene-2,3-diol diacetate, respectively, to produce 2,3-DHN for signal stimuli. The ß-Glu and LPS were detected with linear ranges of 0.01-10.0 U/mL and 0.001-5.0 mg/mL, respectively. Detection limits of 3.3 × 10-3 U/mL and 0.32 µg/mL (S/N = 3) were achieved, for ß-Glu and LPS, respectively. The present study not only provides a new strategy for spontaneous induction of VOs in situ for n-type semiconductors, but also innovates the anodic PEC signal transduction strategy with broadened biosensing applications.


Assuntos
Técnicas Biossensoriais , Nanotubos , Compostos Férricos , Lipopolissacarídeos , Estudos Prospectivos , Glucosídeos , Lipase , Oxigênio
19.
Environ Sci Pollut Res Int ; 30(20): 58998-59012, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37000392

RESUMO

The development of efficient photocatalysts for the photodegradation of organic dyes in wastewater is highly worthwhile. Herein, the nanoemulsion tactic was utilized to synthesize BixSn6-2xSy (0.33 ≤ x ≤ 2.95) photocatalysts with morphological structures that changed from nanowhiskers to quantum dots (QDs). The optical properties of these materials were examined by UV-visible absorbance spectroscopy and photoluminescence, while Mott-Schottky analysis was utilized to study their electronic properties. BixSn6-2xSy materials exhibit appreciable absorption in the UV-visible light range with a direct band gap that increases from 1.23 to 1.46 eV. Both crystal structure and composition greatly affect the photocatalytic activity of BixSn6-2xSy semiconductors. Among the various synthesized photocatalysts, BiSn4S4.5 can efficiently photodegrade methylene blue dye (MB) in the shortest time under UV-visible light. The photocatalytic activity is positively affected by the change of crystal structure from orthorhombic to cubic symmetry. Based on the Mott-Schottky plots, the flat band potential (Efb) and the semiconductor behavior of the fabricated BixSn6-2xSy nanomaterials were determined. The obtained Efb values for SnS, Bi0.33Sn5.34S5.8, BiSn4S5.5, and Bi2.14Sn1.71S4.7 are -0.18 V, -0.42 V, -0.53 V, and -0.51 V (vs. Ag/AgCl), respectively. The Efb value is clearly shifted towards more negative potential values with increasing the Bi molar ratio (x). However, Bi2.95Sn0.1S4.5 semiconductor was found to be of n-type character, having a positive Efb value of +0.66 V (vs. Ag/AgCl). Photocurrent and EIS responses confirm the high stability and photocatalytic activity of BiSn4S5.5, which also achieves the lowest charge transfer resistance. The modified electronic properties of the BixSn6-2xSy semiconductors significantly improve their photocatalytic activity, rendering them to be promising absorbers for sunlight harvesting applications.


Assuntos
Pontos Quânticos , Água , Azul de Metileno/química , Catálise , Semicondutores
20.
Res Q Exerc Sport ; 94(2): 568-577, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35426763

RESUMO

Purpose: In basketball, tactical instructions are presented on tactic boards under temporal constraints (e.g., time-outs). Based on the disparity in the orientation of the tactic board and the players' egocentric on-court visual perspective, there are high affordances in visual-spatial transformation (e.g., mental rotation), which impede information processing and decrease execution accuracy. The aim of this study was to scrutinize how the effect of different orientations of visual tactical displays on information processing demands and execution accuracy is affected by expertise in basketball. Methods: In a mixed-factors-design with two factors, 48 participants were assigned to a group of experienced basketball players (n = 24) and novices (n = 24). They were instructed to execute basketball playing patterns, which were presented on a virtual tactic board in five different spatial disparities to the players' on-court perspective. Results: The self-controlled time for watching the instructions before execution was significantly shorter and spatial accuracy in pattern execution was significantly higher for lower disparities between instruction perspective and on-court perspective. Experienced basketball players displayed shorter observation times as well as higher accuracy as a global effect, being independent of stimulus orientation. Moreover, the effect of orientation on observation times was lower in the experienced group as compared to the novices. Conclusion: Extensive experience over several years with visuo-spatial transformations of tactical instructions reduced, but not eliminated, the effects of model-observer disparity. Accordingly, coaches should align their tactic boards to their players' on-court viewing perspective to enable fast processing and errorless execution of tactical instructions.


Assuntos
Desempenho Atlético , Basquetebol , Humanos , Cognição
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