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Findings on the emergence and interpretation of early object representation in the first year of life diverge widely between designs that employ looking times versus action-based measures. As a promising new approach, pupillometry has produced evidence for object permanence at 18 months of age, but not younger as of yet. In the current study, we (re)investigated object permanence following occlusion events in a pupillometric violation-of-expectation paradigm optimized for younger infants. During each trial, infants observed a toy object's occlusion and prompt reveal in the expected condition or its absence in the unexpected condition. Across two experiments, we show that 10- and 12-month-old infants' (total N = 82) pupils dilate in response to unexpected object disappearances relative to expected appearances. Control analyses revealed no differences between the scenes before the experimental manipulation, excluding perceptual interpretations. We further report an age-dependent effect of condition on pupil responses, with unexpected outcomes triggering greater pupil dilation in the older group. These results provide positive pupillometric evidence in support of object permanence in the context of a violation-of-expectation paradigm at 10 and 12 months of age.

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Evidence of detour ability to reach a salient goal in marine fishes (Chromis viridis, Chrysiptera parasema, Dascyllus aruanus) and freshwater fishes (Xenotoca eiseni, Danio rerio) has been observed using a "four-compartment box task" with an opaque barrier. The first experiment investigated this ability in marine fishes (Chromis viridis, Chrysiptera parasema, Dascyllus aruanus). Fish were placed in a four-compartment box, with social stimuli not accessible due to an opaque barrier. Two symmetrical apertures midline in the corridor allowed the fish to temporarily abandon the goal's view and attempt to circumvent the barrier. Marine fish showed searching behavior in the two compartments near the social stimuli. In the second experiment, the detour abilities of a marine fish (Dascyllus aruanus) and two freshwater fishes (Xenotoca eiseni, Danio rerio) were compared using a modified version of the apparatus, with elongated compartments continuing further from the obstacle barrier and social stimuli. This enabled the evaluation of the dependence on effective distance to achieve the social goal. Both marine and freshwater fish exhibited detour skills. Additionally, Danio rerio's differential spatial explorations inside compartments supported an active interest in searching for conspecifics, suggesting possible social object permanence retention. Overall, these results highlight the ecological salience of detour skills in fishes, irrespective of species-specific adaptations.

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Piagetian object permanence (OP) refers to the ability to know that an object continues to exist when out of sight: In humans, it develops in six stages. Species of great apes, other mammals, and birds (parrots, corvids, and pigeons) have been shown to possess partial or full OP, which is a prerequisite for more complex physical cognition abilities they may possess. In birds, the greatest variation is in Stage 6 (invisible displacements) and in "A-not-B" errors-incorrectly persevering in searching an empty location rewarded previously. Caching abilities have been invoked as holding explanatory power over results in corvids, for which this error is sometimes completely absent. The rook (Corvus frugilegus), a cognitively advanced, social, caching corvid, has not yet been studied for OP. This study applies tasks of one OP scale commonly adapted for nonhuman animals, Uzgiris and Hunt's Scale 1, as well as later-conceived tasks 16 and S, to a sample of adult, captive rooks. One rook demonstrated full OP (Stage 6b, multiple invisible displacements), whereas other individuals varied, attaining between Stages 5a (single visible displacements) and 6a (single invisible displacements). Like some corvids, a few made transient "A-not-B" errors. Behavioral considerations potentially underlying observed individual variation in results in rooks, including dominance, neophobia, past experiences, and individual idiosyncrasies, are examined. Rooks, like other corvids, possess well-developed OP abilities, and these results support the idea that exertion of executive control is required to avoid "A-not-B" errors, rather than caching abilities or developmental age, as previously suggested.

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Mice of two strains selected for successful solution of "object permanence" test and for lack of such solution demonstrated the differential reaction to injections of two drugs. The effects of injections of atomoxetine. which blocks the noradrenaline reuptake, and of 'non-benzodiazepine" anxiolytic afobazol was different. The success of solutions increased in mice selected for this test "non-solution": and decreased or was inefficient in mice, selected for successful solution of object permanence cognitive test.

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In this paper, we consider a stochastic two-species predator-prey system with modified Leslie-Gower. Meanwhile, we assume that hunting cooperation occurs in the predators. By using Itô formula and constructing a proper Lyapunov function, we first show that there is a unique global positive solution for any given positive initial value. Furthermore, based on Chebyshev inequality, the stochastic ultimate boundedness and stochastic permanence are discussed. Then, under some conditions, we prove the persistence in mean and extinction of system. Finally, we verify our results by numerical simulations.

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In their natural environment, animals face a variety of ecological and social challenges, which might be linked to the emergence of different cognitive skills. To assess inter-specific variation in cognitive skills, we used ungulates as a study model, testing a total of 26 captive individuals across 5 different species (i.e., dwarf goats, Capra aegagrus hircus, llamas, Lama glama, guanacos, Lama guanicoe, zebras, Equus grevyi, and rhinos, Diceros bicornis michaeli). Across species, we used the same well-established experimental procedures to test individuals' performance in naïve physics tasks, i.e. object permanence, short-term spatial memory, causality, understanding of object properties, and gravity. Our results revealed that study subjects showed object permanence, were able to remember the position of hidden food after up to 60 s, and inferred the position of hidden food from the sound produced or not produced when shaking containers. Moreover, they showed an understanding of basic object properties, being able to locate objects hidden behind occluders based on their size and inclination, and could reliably follow the trajectory of falling objects across different conditions. Finally, inter-specific differences were limited to the understanding of object properties, and suggest that domesticated species as goats might perform better than non-domesticated ones in tasks requiring these skills. These results provide new information on the cognitive skills of a still understudied taxon and confirm ungulates as a promising taxon for the comparative study of cognitive evolution.

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When an academic paper is published in a journal that assigns a digital object identifier (DOI) to papers, this is a de facto fait accompli. Corrections or retractions are supposed to follow a specific protocol, especially in journals that claim to follow the Committee on Publication Ethics (COPE) guidelines. In this paper, we highlight a case of a new, fully open access neuroscience journal that claims to be COPE-compliant, yet has silently retracted two papers since all records, bibliometrics, and PDF files related to their existence have been deleted from the journal's website. Although this phenomenon does not seem to be common in the neurosciences, we consider that any opaque corrective measures in journals whose papers could be cited may negatively impact the wider neuroscience literature and community. Instead, we encourage transparency in retraction to promote truthfulness and trustworthiness.

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Metronomic chemotherapy refers to the frequent administration of chemotherapeutic agents at a lower dose and presents an attractive alternative to conventional chemotherapy with encouraging response rates. However, the schedule of the therapy, including the dosage of the drug, is usually based on empiricism. The confounding effects of tumor-endothelial-immune interactions during metronomic administration of drugs have not yet been explored in detail, resulting in an incomplete assessment of drug dose and frequency evaluations. The present study aimed to gain a mechanistic understanding of different actions of metronomic chemotherapy using a mathematical model. We have established an analytical condition for determining the dosage and frequency of the drug depending on its clearance rate for complete tumor elimination. The model also brings forward the immune-mediated clearance of the tumor during the metronomic administration of the chemotherapeutic agent. The results from the global sensitivity analysis showed an increase in the sensitivity of drug and immune-mediated killing factors toward the tumor population during metronomic scheduling. Our results emphasize metronomic scheduling over the maximum tolerated dose (MTD) and define a model-based approach for approximating the optimal schedule of drug administration to eliminate tumors while minimizing harm to the immune cells and the patient's body.

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BACKGROUND: Living in a social dominance hierarchy presents different benefits and challenges for dominant and subordinate males and females, which might in turn affect their cognitive needs. Despite the extensive research on social dominance in group-living species, there is still a knowledge gap regarding how social status impacts brain morphology and cognitive abilities. METHODS: Here, we tested male and female dominants and subordinates of Neolamprologus pulcher, a social cichlid fish species with size-based hierarchy. We ran three executive cognitive function tests for cognitive flexibility (reversal learning test), self-control (detour test), and working memory (object permanence test), followed by brain and brain region size measurements. RESULTS: Performance was not influenced by social status or sex. However, dominants exhibited a brain-body slope that was relatively steeper than that of subordinates. Furthermore, individual performance in reversal learning and detour tests correlated with brain morphology, with some trade-offs among major brain regions like telencephalon, cerebellum, and optic tectum. CONCLUSION: As individuals' brain growth strategies varied depending on social status without affecting executive functions, the different associated challenges might yield a potential effect on social cognition instead. Overall, the findings highlight the importance of studying the individual and not just species to understand better how the individual's ecology might shape its brain and cognition.

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In this paper, we investigate the asymptotic behavior of a modified chemostat model. We first demonstrate the existence of equilibria. Then, we present a mathematical analysis for the model, the invariance, the positivity, the persistence of the solutions, and the asymptotic global stability of the interior equilibrium. Some numerical simulations are carried out to illustrate the main results.

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This research paper delves into the two-dimensional discrete plant-herbivore model. In this model, herbivores are food-limited and affect the plants' density in their environment. Our analysis reveals that this system has equilibrium points of extinction, exclusion, and coexistence. We analyze the behavior of solutions near these points and prove that the extinction and exclusion equilibrium points are globally asymptotically stable in certain parameter regions. At the boundary equilibrium, we prove the existence of transcritical and period-doubling bifurcations with stable two-cycle. Transcritical bifurcation occurs when the plant's maximum growth rate or food-limited parameter reaches a specific boundary. This boundary serves as an invasion boundary for populations of plants or herbivores. At the interior equilibrium, we prove the occurrence of transcritical, Neimark-Sacker, and period-doubling bifurcations with an unstable two-cycle. Our research also establishes that the system is persistent in certain regions of the first quadrant. We demonstrate that the local asymptotic stability of the interior equilibrium does not guarantee the system's persistence. Bistability exists between boundary attractors (logistic dynamics) and interior equilibrium for specific parameters' regions. We conclude that changes to the food-limitation parameter can significantly alter the system's dynamic behavior. To validate our theoretical findings, we conduct numerical simulations.

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Mentoring programs have been proposed to reduce dropout and increase academic performance. We analyzed the effect of peer mentoring on university dropout and academic performance in the context of Spain. We applied a quasi-experimental posttest-only control group design with 3,774 students (mentees, n = 1,887; control, n = 1,887). Mentees had participated in a peer mentoring program. We apply the student’s t-test, Cohen’s d, phi statistic, and chi-square statistic. Mentees exhibited lower dropout than controls and showed higher academic performance regardless of the area of knowledge. Results support the implementation of mentoring programs in Spanish universities with the goal of reducing student dropout and increasing academic performance. The research provides empirical evidence for theory building in higher education studies, developmental relationships, and integration programs. (AU)

Se ha propuesto la aplicación de programas de mentoría para reducir la deserción universitaria y aumentar el rendimiento académico. En el artículo analizamos el efecto de la mentoría entre pares sobre el abandono universitario y el rendimiento académico en España. Aplicamos un diseño de grupo de control cuasiexperimental con medida post en una muestra de 3.774 estudiantes (mentorados, n = 1,887; control, n = 1,887). Los mentorados habían participado en un programa de mentoría entre pares. Aplicamos la prueba t de Student, la d de Cohen, el estadístico phi y el chi-cuadrado. Los mentorados presentaban un menor abandono que los controles y un mayor rendimiento académico independientemente del área de conocimiento. Los resultados avalan la implementación de programas de mentoría en las universidades españolas con el objetivo de reducir el abandono universitario y aumentar el rendimiento académico. La investigación proporciona evidencia empírica para la elaboración de teorías en estudios de educación superior, relaciones de desarrollo y programas de integración. (AU)

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Object permanence, the ability to mentally represent objects even when they are not directly accessible to the senses, is of vital importance for the survival of both human and non-human animals. The Oriental pied hornbill (Anthracoceros albirostris) is an Asian species of hornbill displaying remarkable adaptability in various environments, yet little is known about their cognitive abilities. Their breeding behaviour is unique, as the female hornbill seals herself inside a cavity before laying eggs and the male feeds her and their offspring without visual contact, strongly suggesting the presence of object permanence to some degree. In this study, six Oriental pied hornbills underwent testing for object permanence, including a series of seven standard Piagetian tasks involving visible and invisible displacements. The subjects consistently demonstrated spontaneous object permanence in all stages leading up to the invisible displacement stage. Half of the subjects achieved full stage 6 double invisible displacement Piagetian object permanence, while the other half reached stage 5 double visible displacement. Breeding behaviour and the duration of developmental stages are proposed as potential factors influencing object permanence ability in this species of hornbill.

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In this paper, we mainly consider a eco-epidemiological predator-prey system where delay is time-varying to study the transmission dynamics of Bacterial white spot disease in Litopenaeus Vannamei, which will contribute to the sustainable development of shrimp. First, the permanence and the positiveness of solutions are given. Then, the conditions for the local asymptotic stability of the equilibriums are established. Next, the global asymptotic stability for the system around the positive equilibrium is gained by applying the functional differential equation theory and constructing a proper Lyapunov function. Last, some numerical examples verify the validity and feasibility of previous theoretical results.

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BACKGROUND: Considering the high maternal mortality rate, the government of Pakistan has deployed Community Midwives (CMWs) in rural areas of Pakistan. This relatively new cadre of community-based skilled birth attendants has previously reported to experience several challenges in providing maternal and child healthcare. However, what barriers they experience in providing basic emergency obstetric and newborn care needs to be further studied. METHODS: This was a cross-sectional study conducted in twelve districts in Sindh province, Pakistan, with poor maternal and child health indicators. A total of 258 CMWs participated in this study and completed the questionnaire on a pretested, validated tool in their community-based stations. The trained data collectors completed the questionnaires from the respondents. The problems identified were categorized into three major issues: financial, and transport and security related; and were analyzed accordingly. Ethical approval was obtained from the institutional review board (IRB) of Health Services Academy (HSA) Islamabad, Pakistan. RESULTS: The majority (90%) of 258 CMWs had formal training in maternal and neonatal care from the recognized institutions. Financial difficulties faced by CMWs were identified as the most frequent barriers and others were transport, security, and other issues. In univariate analysis, 38.1% and 61.9% of the community midwives who faced financial difficulties had completed a graduation or intermediate level of education, respectively (p = 0.006). Round-the-clock availability for emergencies was inversely associated with having financial difficulties, i.e., 71.4%, in contrast to 28.4% who had financial difficulties were available round-the-clock for emergency calls in their community clinics (p = 0.008). Formal training (p = 0.001), work experience (p = 0.015), longer duration of work (p = 0.003), and liaison with health workers and posting district (p = 0.001) had statistically significantly higher transport related issues. Security difficulties faced by CMWs and a set of correlates such as formal training (p = 0.019), working experience (p = 0.001), longer duration of work (p = 0.023), 24 h of availability on call (p = 0.004), liaison with traditional birth attendants (TBAs) in the community (p = 0.002), and district of posting (p = 0.001) were statistically significantly different. Other issues like working experience (p = < 0.001) and Liaison with TBAs in the community (p = < 0.001) were found statistically significant. CONCLUSION: Financial, transportation and security related barriers were commonly reported by community midwives in the delivery of basic emergency obstetric and newborn care in rural Pakistan.

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Modern coexistence theory (MCT) is one of the leading methods to understand species coexistence. It uses invasion growth rates-the average, per-capita growth rate of a rare species-to identify when and why species coexist. Despite significant advances in dissecting coexistence mechanisms when coexistence occurs, MCT relies on a 'mutual invasibility' condition designed for two-species communities but poorly defined for species-rich communities. Here, we review well-known issues with this component of MCT and propose a solution based on recent mathematical advances. We propose a clear framework for expanding MCT to species-rich communities and for understanding invasion resistance as well as coexistence, especially for communities that could not be analysed with MCT so far. Using two data-driven community models from the literature, we illustrate the utility of our framework and highlight the opportunities for bridging the fields of community assembly and species coexistence.

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INTRODUCTION: PASS is a hospital care unit that provides access to health care for precarious persons and supports them as soon as they have obtained primary health care insurance. No details of this support had previously been described. A Hospital-to-Community protocol for referral to the public health system has been developed at the adult PASS unit of the Marseille public hospitals (AP-HM). The objectives of this study are to describe how this protocol is applied, to evaluate at six months the inclusion in general practice of patients having benefited (or not) from this protocol and to determine the key influencing factors. MATERIAL AND METHOD: This two-arm prospective observational study collected data on the primary care pathways of precarious patients six months after their having obtained health coverage, and found out whether or not the newly existing protocol had been effectively implemented. It was carried out on a cohort of people included in the PASS-MULTI study who had acquired complete health coverage. RESULTS: Sixty patients were included between November 2020 and August 2022, 35 of whom had availed themselves of the Hospital-to-Community protocol. Among them, 68.8% in the interventional group had consulted their referring general practitioner within six months, vs. 40% in the control group (p = 0.04). The initiation of follow-up in general medicine was associated with application of the protocol (p = 0.04). CONCLUSION: This study described an initial Hospital-to-Community protocol for referral to the primary healthcare system of patients followed up in the PASS unit and found an association between application of this protocol and initiation of follow-up in primary healthcare.

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Executive functions are a set of cognitive control processes required for optimizing goal-directed behavior. Despite more than two centuries of research on executive functions, mostly in humans and nonhuman primates, there is still a knowledge gap in what constitutes the mechanistic basis of evolutionary variation in executive function abilities. Here, we show experimentally that size changes in a forebrain structure (i.e. telencephalon) underlie individual variation in executive function capacities in a fish. For this, we used male guppies (Poecilia reticulata) issued from artificial selection lines with substantial differences in telencephalon size relative to the rest of the brain. We tested fish from the up- and down-selected lines not only in three tasks for the main core executive functions: cognitive flexibility, inhibitory control, and working memory, but also in a basic conditioning test that does not require executive functions. Individuals with relatively larger telencephalons outperformed individuals with smaller telencephalons in all three executive function assays but not in the conditioning assay. Based on our findings, we propose that the telencephalon is the executive brain in teleost fish. Together, it suggests that selective enlargement of key brain structures with distinct functions, like the fish telencephalon, is a potent evolutionary pathway toward evolutionary enhancement of advanced cognitive abilities in vertebrates.

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In this work, we set up a new discrete predator-prey competitive model with time-varying delays and feedback controls. By virtue of the difference inequality knowledge, a sufficient condition which guarantees the permanence of the established discrete predator-prey competitive model with time-varying delays and feedback controls is derived. Under some appropriate parameter conditions, we have proved that the periodic solution of the system without delay exists and globally attractive. To verify the correctness of the derived theoretical fruits, we give two examples and execute computer simulations. Our obtained results are novel and complement previous known results.

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Este artículo profundiza en el conocimiento de las mujeres habitantes de la calle de las cinco ciudades más densas del país, teniendo como telón de fondo las relaciones patriarcales de desigualdad que permean los diferentes momentos de la habitanza de la calle empezando por la decisión de salir a vivir en esta. Con la información disponible de los censos de habitantes de la calle de 2017 y 2019 realizados por el Departamento Administrativo Nacional de Estadística (DANE) en Bogotá, Medellín, Cali, Barranquilla y Bucaramanga, indaga las diversas formas femeninas de habitar la calle y las condiciones en que esta se lleva a cabo. Apunta básicamente a eliminar la masculinización de la habitanza de la calle, visibilizando la presencia de mujeres diversas en ciclos de vida y con vivencias expulsoras antes y de hábitos de subsistencia y manutención durante su permanencia en la calle.

This article delves into the knowledge of women living on the streets of the five densest cities in the country, taking as a background the patriarchal relations of inequality that permeate the different moments of street life starting with the decision to go out to live in this. With the information available from the censuses of street dwellers of 2017 and 2019 carried out by DANE in Bogotá, Medellín, Cali, Barranquilla and Bucaramanga, it investigates the various female ways of inhabiting the street and the conditions in which it is carried out. It basically aims to eliminate the masculinization of street living, making visible the presence of diverse women in life cycles and with expeller experiences before and of subsistence and maintenance habits during their stay on the street.