5,202 research outputs found
Molecular Mechanisms Regulating Neonatal Oocyte Survival and Primordial Follicle Formation in the Mouse Ovary
In mammals, formation of the primordial follicle is a complex process involving the breakdown of germ cell cysts, where oocytes must separate from each other and subsequently become surrounded by somatic cells. As cysts separate, a large number of germ cells are lost by apoptosis, however the mechanisms by which cyst breakdown and germ cell death occur are not well understood. We first hypothesized that two anti-apoptotic regulators from the BCL2 family of proteins, BCL2 and MCL1, may be responsible for regulating neonatal oocyte survival. To elucidate the effects of BCL2 in the neonatal ovary, we examined ovaries of both Bcl2 overexpressing and knockout transgenic mice. When compared to wild-type mice, neither Bcl2 overexpression nor abrogation significantly altered ovarian histology. Another BCL2 family protein, MCL1, is expressed in human oocytes during ovarian development, suggesting a role for MCL1 in oocyte survival. We found that MCL1 was localized to both oocytes and somatic cells during cyst breakdown. Subsequently, we used an in vitro organ culture system to identify a role for MCL1 in oocyte survival. We found that inhibition of MCL1 with an antibody to MCL1 in culture resulted altered germ cell numbers and oocyte cyst breakdown. Our data demonstrate that while BCL2 is not likely involved in perinatal oocyte survival, MCL1 may be an important regulator of the ovarian primordial follicle reserve. Next, we hypothesized that the KIT signaling pathway may be important for oocyte survival and cyst breakdown in the neonatal ovary. The tyrosine kinase receptor, KIT, and its ligand, KITL, have been implicated in oocyte survival and follicle development in both fetal and adult ovaries but have not been well studied at the perinatal time point. To elucidate the functional role of KIT signaling in the neonatal ovary, we began by using immunohistochemistry to test the expression of KIT and KITL. We found both proteins to be expressed in the developing ovary from 17.5 dpc to PND 3, suggesting an important role for this protein in cyst breakdown or oocyte survival. To test this hypothesis, ovaries from 17.5 dpc fetal mice were cultured for 5 days in control media, or in media with the KIT blocking antibody, ACK2, or recombinant KITL. Our data demonstrated a role for KIT signaling in cyst breakdown, as inhibition and activation of the pathway altered ovarian histology. Using cell proliferation and TUNEL assays at the conclusion of culture, we identified a reduction in somatic cell proliferation when KIT signaling was inhibited and likewise, a decrease in cell death. Finally, we investigated which pathway downstream of KIT affects cyst breakdown and the effect of KIT signaling on MCL1 protein expression. After 3 days in culture with KITL supplemented media, Western blotting was used to analyze the total and phosphorylated forms of proteins from the PI3K, MAPK and JAK-STAT pathways as well as the BCL2 family protein, MCL1. We found that there was an increase in the phosphorylated forms of p44/p42 in the MAPK pathway and a downregulation of MCL1 on KIT activation. Overall our data have shown that while BCL2 may not contribute to oocyte survival during cyst breakdown, both MCL1 and KIT play important roles in formation of the primordial follicle pool
Sequential effects in facial attractiveness judgments using cross-classified models: Investigating perceptual and response biases.
When evaluating items in a sequence, the current judgment is influenced by the previous item and decision. These sequential biases take the form of assimilation (shifting toward the previous item/decision) or contrast (shifting away). Previous research investigating facial attractiveness evaluations provides mixed results while using analytical techniques that fail to address the dependencies in the data or acknowledge that the images represent only a subset of the population. Here, we utilized cross-classified linear mixed-effects modeling across 5 experiments. We found compelling evidence of multicollinearity in our models, which may explain apparent contradictions in the literature. Our results demonstrated that the previous imageâs rating positively influenced current ratings, and this was also the case for the previous imageâs baseline value, although only when that image remained onscreen during the current trial. Further, we found no influence of the next face on current judgments when this was visible. In our final experiment, the response bias due to the previous trial remained present even when accounts involving motor effort were addressed. Taken together, these findings provide a clear framework in which to incorporate current and past results regarding the biases apparent in sequential judgments, along with an appropriate method for investigating these biases
Wanting or having children predicts age preferences in online dating
When dating, women seek men slightly older than themselves while men typically prefer younger women. Such patterns reflect differences in parental investment and age-related fertility, which are both concerned with maximizing reproductive outcomes. Using large samples of online daters, we considered whether having or wanting children was associated with the perceived importance of age as a matching criterion when dating (Study 1; N = 119,361), as well as how these two factors related to the preferred age of a match (Study 2; N = 486,382). Men without children (or those who wanted children) rated age as more important than those with children (or those who did not want children), and also selected a preferred age range that incorporated younger women. In contrast, womenâs preferences showed little association with having or wanting children. Taken together, these findings demonstrate that age preferences may depend on factors in addition to those previously investigated, and that the relationships with the number of current children and the desire to have children are consistent with evolutionary predictions
Individual differences in face and voice matching abilities: The relationship between accuracy and consistency
Deciding whether two different face photographs or voice samples are from the same person represent fundamental challenges within applied settings. To date, most research has focussed on average performance in these tests, failing to consider individual differences and withinâperson consistency in responses. Here, participants completed the same face (Experiment 1) or voice matching test (Experiment 2) on two separate occasions, allowing comparison of overall accuracy across the two timepoints as well as consistency in trialâlevel responses. In both experiments, participants were highly consistent in their performances. In addition, we demonstrated a large association between consistency and accuracy, with the most accurate participants also tending to be the most consistent. This is an important result for applied settings in which organisational groups of superâmatchers are deployed in realâworld contexts. Being able to reliably identify these high performers based upon only a single test informs regarding recruitment for law enforcement agencies worldwide
INNOVATIVE APPROACHES IN COACH EDUCATION PEDAGOGY
ABSTRACT: We know that coach education programmes continue to be criticized for their largely didactic methods of delivery and rather superficial engagement with the complex reality of practice and we understand that innovative approaches in coach education pedagogy means moving somewhat away from the competencies based approach and it has been increasingly argued that the aim of coach education should be to develop in practitioners a âquality of mindâ so that they are better equipped to deal with the problematic and dynamic nature of their work. The skills of coach educators in facilitating the learning of student coaches are crucial to the effectiveness of the pedagogies. Coach educators, therefore, must be committed to the approaches outlined in this article and invest the time and work necessary to learning new skills if they are to be successfully implemented. We found that teaching in this way resulted in a raised degree of responsibility on behalf of the tutors, not so much in relation to their content delivery, but for the subsequent student interaction and learning (JONES et al., 2011). In this sense tutors took greater care to listen and react to group interactions, recognising that their (non) interventions at (in) appropriate times could genuinely affect and frame ensuing studentsâ discussions and perceptions. A further area of research, therefore, could be to explore the issues surrounding the training and support of coach educators in implementing such pedagogical innovative approaches to coach education. RESUMO: Sabemos que os trabalhos de orientação de tĂŠcnicos/professores sĂŁo muito criticados por seus mĂŠtodos pouco se aproximarem de prĂĄticas inovadoras. No entanto, prĂĄticas pedagĂłgicas inovadoras devem se aproximar da realidade prĂĄtica e avançar aos mĂŠtodos tradicionais, considerando que uma pedagogia inovadora deve mover alguĂŠm do lugar onde se encontra para conhecer novas possibilidades. As habilidades dos tĂŠcnicos/professores devem ser trabalhadas no sentido dos mesmos se constituĂrem facilitadores do processo de aprendizagem dos estudantes para se pensar numa pedagogia inovadora. Entendemos que uma concepção pedagĂłgica construĂda nessa direção possibilita o desenvolvimento tanto de tĂŠcnicos/professores, assim como os estudantes e pesquisas educacionais devem caminhar nessa direção, tendo em vista a necessidade de transformação qualitativa dessa ĂĄreade atuação.http://dx.doi.org/10.14572/nuances.v24i1.217
Face Familiarity and Image-Specific Memory
Face familiarity produces advantages for both memory and matching. By developing an internal representation through repeated experience, viewers extract identity-specific information that aids subsequent recognition. However, researchers have recently argued that this process may also result in a familiarity disadvantage, whereby specific instances of the face are more difficult to remember, perhaps due to this process of prioritising identity- over image-specific information. Although previous experiments found no evidence of this disadvantage in working memory, initial research has demonstrated an effect in longer term storage. Here, we attempted to replicate this finding by focussing on the ability to learn images of a single (un)familiar identity. Our results failed to demonstrate a familiarity disadvantage while replicating the finding that familiarity influences response bias. As researchers continue to investigate how familiarity alters both internal representations and associated processes, it is important to establish which processes may or may not be affected
On the derivative of the associated Legendre function of the first kind of integer order with respect to its degree
In our recent works [R. Szmytkowski, J. Phys. A 39 (2006) 15147; corrigendum:
40 (2007) 7819; addendum: 40 (2007) 14887], we have investigated the derivative
of the Legendre function of the first kind, , with respect to its
degree . In the present work, we extend these studies and construct
several representations of the derivative of the associated Legendre function
of the first kind, , with respect to the degree , for
. At first, we establish several contour-integral
representations of . They are then
used to derive Rodrigues-type formulas for with . Next, some closed-form
expressions for are
obtained. These results are applied to find several representations, both
explicit and of the Rodrigues type, for the associated Legendre function of the
second kind of integer degree and order, ; the explicit
representations are suitable for use for numerical purposes in various regions
of the complex -plane. Finally, the derivatives
, and , all with , are evaluated in terms
of .Comment: LateX, 40 pages, 1 figure, extensive referencin
Incomplete faces are completed using a more average face
Facial first impressions are known to influence how we behave towards others. As a result of the COVID-19 pandemic, we often view incomplete faces due to the commonplace wearing of face masks. Previous research has shown that perceptions of attractiveness are often increased due to these coverings, with initial evidence suggesting that this may be caused by viewers using a mental representation of the average face to complete any missing information. Here, we directly address this hypothesis by presenting participants with incomplete faces (either the lower or upper half removed) and asking them to decide how they thought the actual, full face looked. Participants were able to manipulate the missing half of the face onscreen by increasing or decreasing the averageness of its shape. Our results demonstrated that participants did not select the original versions of the faces but instead chose more average versions when manipulating both the lower and upper face. Further, the typicality of the original image influenced responses, with less typical faces (in comparison with more typical ones) being completed using an even more average version of the missing half of the faces. Taken together, these findings provide the first direct evidence that people utilise an average/typical internal representation when inferring information about incomplete faces. This result has theoretical importance in terms of visual perception, as well as real-world relevance in a time where face masks are commonplace due to the COVID-19 pandemic
Targeting the Insulin-Like Growth Factor 1 Receptor in Ewing's Sarcoma: Reality and Expectations
Ewing's sarcoma family of tumours comprises a group of very aggressive diseases that are potentially curable with multimodality treatment. Despite the undoubted success of current treatment, approximately 30% of patients will relapse and ultimately die of disease. The insulin-like growth factor 1 receptor (IGF-1R) has been implicated in the genesis, growth, proliferation, and the development of metastatic disease in Ewing's sarcoma. In addition, IGF1-R has been validated, both in vitro and in vivo, as a potential therapeutic target in Ewing's sarcoma. Phase I studies of IGF-1R monoclonal antibodies reported several radiological and clinical responses in Ewing's sarcoma patients, and initial reports of several Phase II studies suggest that about a fourth of the patients would benefit from IGF-1R monoclonal antibodies as single therapy, with approximately 10% of patients achieving objective responses. Furthermore, these therapies are well tolerated, and thus far severe toxicity has been rare. Other studies assessing IGF-1R monoclonal antibodies in combination with traditional cytotoxics or other targeted therapies are expected. Despite, the initial promising results, not all patients benefit from IGF-1R inhibition, and consequently, there is an urgent need for the identification of predictive markers of response
Early responses to H7N9 in southern mainland China
This article is made available through the Brunel Open Access Publishing Fund. Š 2014 Goodwin and Sun; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the
Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public
Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this
article, unless otherwise stated.Background: H7N9 posed potentially serious health challenges for Chinese society. The previous SARS outbreak in this country was accompanied by contradictory information, while worries about wide-spread influenza led to discrimination worldwide. Early understanding of public threat perceptions is therefore important for effective public health communication and intervention. Methods: We interviewed 1011 respondents by phone two weeks after the first case. Questions examined risk awareness and media use, beliefs about the emergence of the threat and those most at risk, anxiety about infection and preventive and avoidant behaviours. Results: Results demonstrate moderate levels of anxiety but relatively high levels of trust towards government officials. Threat emergence was associated with hygiene levels, temperature change, floating pigs in the Huangpu River and migration to the city. Anxiety predicted both recommended and non-recommended behavioural changes. Conclusions: Comparatively high levels of trust in Chinese government advice about H7N9 contrast positively with previous pandemic communications in China. Anxiety helped drive both recommended and non-recommended behaviours, with potentially important economic and social implications. This included evidence of 'otheringâ of those associated with the threat (e.g. migrants). Findings emphasise the need to manage public communications early during new influenza outbreaks.Fudan Tydall Centre and Fudan Media and Public Opinion Center
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