277 research outputs found
A Non-Lévy Random Walk in Chacma Baboons: What Does It Mean?
The Lévy walk is found from amoebas to humans and has been described as the optimal strategy for food research. Recent results, however, have generated controversy about this conclusion since animals also display alternatives to the Lévy walk such as the Brownian walk or mental maps and because movement patterns found in some species only seem to depend on food patches distribution. Here I show that movement patterns of chacma baboons do not follow a Lévy walk but a Brownian process. Moreover this Brownian walk is not the main process responsible for movement patterns of baboons. Findings about their speed and trajectories show that baboons use metal maps and memory to find resources. Thus the Brownian process found in this species appears to be more dependent on the environment or might be an alternative when known food patches are depleted and when animals have to find new resources
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Open science, communal culture, and women’s participation in the movement to improve science
Science is undergoing rapid change with the movement to improve science focused largely on reproducibility/replicability and open science practices. This moment of change—in which science turns inward to examine its methods and practices—provides an opportunity to address its historic lack of diversity and noninclusive culture. Through network modeling and semantic analysis, we provide an initial exploration of the structure, cultural frames, and women’s participation in the open science and reproducibility literatures (n = 2,926 articles and conference proceedings). Network analyses suggest that the open science and reproducibility literatures are emerging relatively independently of each other, sharing few common papers or authors. We next examine whether the literatures differentially incorporate collaborative, prosocial ideals that are known to engage members of underrepresented groups more than independent, winner-takes-all approaches. We find that open science has a more connected, collaborative structure than does reproducibility. Semantic analyses of paper abstracts reveal that these literatures have adopted different cultural frames: open science includes more explicitly communal and prosocial language than does reproducibility. Finally, consistent with literature suggesting the diversity benefits of communal and prosocial purposes, we find that women publish more frequently in high-status author positions (first or last) within open science (vs. reproducibility). Furthermore, this finding is further patterned by team size and time. Women are more represented in larger teams within reproducibility, and women’s participation is increasing in open science over time and decreasing in reproducibility. We conclude with actionable suggestions for cultivating a more prosocial and diverse culture of science
Aging Impairs Recipient T Cell Intrinsic and Extrinsic Factors in Response to Transplantation
As increasing numbers of older people are listed for solid organ transplantation, there is an urgent need to better understand how aging modifies alloimmune responses. Here, we investigated whether aging impairs the ability of donor dendritic cells or recipient immunity to prime alloimmune responses to organ transplantation.Using murine experimental models, we found that aging impaired the host environment to expand and activate antigen specific CD8(+) T cells. Additionally, aging impaired the ability of polyclonal T cells to induce acute allograft rejection. However, the alloimmune priming capability of donor dendritic cells was preserved with aging.Aging impairs recipient responses, both T cell intrinsic and extrinsic, in response to organ transplantation
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
Developing and pre-testing a decision board to facilitate informed choice about delivery approach in uncomplicated pregnancy
<p>Abstract</p> <p>Background</p> <p>The rate of caesarean sections is increasing worldwide, yet medical literature informing women with uncomplicated pregnancies about relative risks and benefits of elective caesarean section (CS) compared with vaginal delivery (VD) remains scarce. A decision board may address this gap, providing systematic evidence-based information so that patients can more fully understand their treatment options. The objective of our study was to design and pre-test a decision board to guide clinical discussions and enhance informed decision-making related to delivery approach (CS or VD) in uncomplicated pregnancy.</p> <p>Methods</p> <p>Development of the decision board involved two preliminary studies to determine women's preferred mode of risk presentation and a systematic literature review for the most comprehensive presentation of medical risks at the time (VD and CS). Forty women were recruited to pre-test the tool. Eligible subjects were of childbearing age (18-40 years) but were not pregnant in order to avoid raising the expectation among pregnant women that CS was a universally available birth option. Women selected their preferred delivery approach and completed the Decisional Conflict Scale to measure decisional uncertainty before and after reviewing the decision board. They also answered open-ended questions reflecting what they had learned, whether or not the information had helped them to choose between birth methods, and additional information that should be included. Descriptive statistics were used to analyse sample characteristics and women's choice of delivery approach pre/post decision board. Change in decisional conflict was measured using Wilcoxon's sign rank test for each of the three subscales.</p> <p>Results</p> <p>The majority of women reported that they had learned something new (n = 37, 92%) and that the tool had helped them make a hypothetical choice between delivery approaches (n = 34, 85%). Women wanted more information about neonatal risks and personal experiences. Decisional uncertainty decreased (p < 0.001) and perceived effectiveness of decisions increased (p < 0.001) post-intervention.</p> <p>Conclusion</p> <p>Non-pregnant women of childbearing age were positive about the decision board and stated their hypothetical delivery choices were informed by risk presentation, but wanted additional information about benefits and experiences. This study represents a preliminary but integral step towards ensuring women considering delivery approaches in uncomplicated pregnancies are fully informed.</p
Neonates’ responses to repeated exposure to a still face
The main aims of the study were to examine whether human neonates' responses to communication disturbance modelled by the still-face paradigm were stable and whether their responses were affected by their previous experience with the still-face paradigm.The still face procedure, as a laboratory model of interpersonal stress, was administered repeatedly, twice, to 84 neonates (0 to 4 day olds), with a delay of an average of 1.25 day.Frame-by-frame analysis of the frequency and duration of gaze, distressed face, crying, sleeping and sucking behaviours showed that the procedure was stressful to them both times, that is, the still face effect was stable after repeated administration and newborns consistently responded to such nonverbal violation of communication. They averted their gaze, showed distress and cried more during the still-face phase in both the first and the second administration. They also showed a carry-over effect in that they continued to avert their gaze and displayed increased distress and crying in the first reunion period, but their gaze behaviour changed with experience, in the second administration. While in the first administration the babies continued averting their gaze even after the stressful still-face phase was over, this carry-over effect disappeared in the second administration, and the babies significantly increased their gaze following the still-face phase.After excluding explanations of fatigue, habituation and random effects, a self-other regulatory model is discussed as a possible explanation for this pattern
The bodily social self: a link between phenomenal and narrative selfhood
The Phenomenal Self (PS) is widely considered to be dependent on body representations, whereas the Narrative Self (NS) is generally thought to rely on abstract cognitive representations. The concept of the Bodily Social Self (BSS) might play an important role in explaining how the high level cognitive self-representations enabling the NS might emerge from the bodily basis of the PS. First, the phenomenal self (PS) and narrative self (NS), are briefly examined. Next, the BSS is defined and its potential for explaining aspects of social cognition is explored. The minimal requirements for a BSS are considered, before reviewing empirical evidence regarding the development of the BSS over the first year of life. Finally, evidence on the involvement of the body in social distinctions between self and other is reviewed to illustrate how the BSS is affected by both the bottom up effects of multisensory stimulation and the top down effects of social identification
Investigação de um sistema de alimentação em recém-nascidos prematuros a partir de estimulação gustativa
Objetivo: investigar a existência do sistema de alimentação em recém-nascidos prematuros a partir da estimulação gustativa. Métodos:
estudo experimental, analítico, duplo-cego. Participaram 90 recém-nascidos prematuros, de uma maternidade pública de Sergipe. O teste foi filmado, constituindo-se por três momentos de cinco minutos. O primeiro e último momento sem realizar estímulo, o segundo momento com estimulação gustativa, sendo que os recém-nascidos foram divididos em dois grupos (água ou sacarose). Foram estudados os comportamentos específicos sucção de mão direita e esquerda, protrusão de língua e movimentos de sucção nos estados comportamentais sono profundo, sono leve, sonolento, agitado/irritado e choro. Para caracterizar a população foram utilizadas média, desvio-padrão e prevalências. Foi utilizado o teste não paramétrico Mann-Whitney para comparação de médias. O teste de Spearman verificou correlação entre estados comportamentais e comportamentos específicos em cada momento do teste. O valor de p foi significante quando menor que 0,05. Resultados: independente do estímulo administrado, a correlação aumentou em todos os comportamentos específicos. Comparando os grupos separadamente, após a estimulação, observou-se aumento de correlação em sucção de mão direita e protrusão de língua para ambos os grupos. O mesmo aconteceu em sucção, com exceção do estado agitado/irritado. Após a estimulação, houve maior correlação para o comportamento de sucção de mão esquerda no grupo sacarose quando comparado ao grupo água. Os resultados evidenciam que estímulos gustativos podem contribuir na prontidão para alimentação nesta população. Conclusões:
evidenciou-se nos recém-nascidos prematuros aumento de correlação para os comportamentos específicos relacionados ao sistema de alimentação, após estimulação oral, o que vislumbra a possibilidade da estimulação gustativa ser utilizada para ativação de um sistema de alimentação em recém-nascidos prematuros. _________________________________________________________________________________________ ABSTRACT: Purpose: to investigate the existence of the alimentation system in premature newborns in response to gustatory stimulation. Methods: experimental, analytical, double-blind study. 90 premature newborns of a public maternity in Sergipe took part in the test which was filmed and divided into three parts of five minutes. In the first and last, there was no stimulus; in the second, the gustatory stimulation was
applied and the newborn children were divided into two groups (water or sucrose). We studied the specific behaviors suction right and left hands, tongue protrusion and suction movements in behavioral states deep sleep, light sleep, drowsy, restless / irritable and crying. In the statistical analysis of the
population, average, standard deviation and prevalence studies were performed. We used the non-parametric Mann-Whitney test to compare averages. The Spearman test observed correlation between behavioral states at each time of the test. The p value was significant when less than 0.05. Results: independent of the given stimulus, the correlation increased in all specific behaviors. Comparing the
groups separately, after stimulation, we observed an increase in correlation in right hand suction and tongue protrusion for both. The same happened in suction, except for the agitated/irritated state. After stimulation, there was a higher correlation to the behavior of left hand suction in the sucrose group when compared to water. The results show that gustatory stimuli may contribute to the readiness to feed this population. Conclusions: it was found in premature newborns an increased in correlation
for the specific behaviors related to the alimentation system after oral stimulation, which envisions the possibility of gustatory stimulation be used for activating a alimentation system in premature newborns
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