355 research outputs found

    The Asymptotic Giant Branches of GCs: Selective Entry Only

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    The handful of available observations of AGB stars in Galactic Globular Clusters suggest that the GC AGB populations are dominated by cyanogen-weak stars. This contrasts strongly with the distributions in the RGB (and other) populations, which generally show a 50:50 bimodality in CN band strength. If it is true that the AGB populations show very different distributions then it presents a serious problem for low mass stellar evolution theory, since such a surface abundance change going from the RGB to AGB is not predicted by stellar models. However this is only a tentative conclusion, since it is based on very small AGB sample sizes. To test whether this problem really exists we have carried out an observational campaign specifically targeting AGB stars in GCs. We have obtained medium resolution spectra for about 250 AGB stars across 9 Galactic GCs using the multi-object spectrograph on the AAT (2df/AAOmega). We present some of the preliminary findings of the study for the second parameter trio of GCs: NGC 288, NGC 362 and NGC 1851. The results indeed show that there is a deficiency of stars with strong CN bands on the AGB. To confirm that this phenomenon is robust and not just confined to CN band strengths and their vagaries, we have made observations using FLAMES/VLT to measure elemental abundances for NGC 6752.We present some initial results from this study also. Our sodium abundance results show conclusively that only a subset of stars in GCs experience the AGB phase of evolution. This is the first direct, concrete confirmation of the phenomenon.Comment: 4 pages, to appear in conference proceedings of "Reading the book of globular clusters with the lens of stellar evolution", Rome, 26-28 November 201

    Development of weCope, a mobile app for illness self-management in schizophrenia

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    Objective: To describe the development of weCope, a Portuguese mobile app for people with schizophrenia. Methods: The development of weCope followed 4 stages: I-102 people with psychotic disorders completed an online questionnaire; II-a multidisciplinary focus group was conducted among five mental health professionals; III-we developed the app; IV-9 participants used weCope during 8 weeks to assess its efficiency. Results: weCope targets coping with voices, problem solving, goals setting and stress management, and results indicated that: weCope improved symptoms, sense of recovery and personal and social functioning; 59% of the participants were willing to download an application for illness self-management; professionals revealed some concerns about mHealth but enhanced the high importance to develop these apps; usability testing revealed that 89% considered weCope useful for illness self-management. However, the more years with mental illness, the less importance is given to a mobile application for this purpose. Discussion: weCope was developed through a comprehensive development process and may contribute to a subjective perception of the patient’s better well-being and health condition

    Surface-enhanced Raman scattering: metal nanostructures coated with Langmuir-Blodgett films

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    This review deals with surface-enhancved Raman scattering (SERS) employing Langmuir-Blodgett (LB) films, which serve as model systems for developing theoretical and experimental studies to elucidate the SERS effect. In addition, LB films have be used as integral parts of molecular architectures for SERS-active substrates. On the other hand, SERS and surface-enhaced resonant Raman scattering (SERRS) have allowed various properties of LB films to be investigated, especially those associated with molecular-level interactions. In the paper, emphasis is placed on single molecule detection (SMD), where the target molecule is diluted on an LB matrix of spectral silent material (low Raman cross section). The perspectives and challenges for combining SERS and LB films are also discussed.FAPESPCNPqCAPESINCT-INEOnBioNet Films & Sensor

    The relationship between sensory sensitivity and autistic traits in the general population.

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    Individuals with Autism Spectrum Disorders (ASDs) tend to have sensory processing difficulties (Baranek et al. in J Child Psychol Psychiatry 47:591–601, 2006). These difficulties include over- and under-responsiveness to sensory stimuli, and problems modulating sensory input (Ben-Sasson et al. in J Autism Dev Disorders 39:1–11, 2009). As those with ASD exist at the extreme end of a continuum of autistic traits that is also evident in the general population, we investigated the link between ASD and sensory sensitivity in the general population by administering two questionnaires online to 212 adult participants. Results showed a highly significant positive correlation (r = .775, p < .001) between number of autistic traits and the frequency of sensory processing problems. These data suggest a strong link between sensory processing and autistic traits in the general population, which in turn potentially implicates sensory processing problems in social interaction difficulties

    A caça e a conservação da fauna silvestre no Estado do Acre.

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    A fauna silvestre representa uma importante fonte alimentar para as pessoas que vivem nas florestas tropicais, além de ser bastante consumida nas áreas urbanas dessas regiões. Neste trabalho, objetivou-se fazer uma discussão do tema caça, através do resgate histórico dos estudos já elaborados no estado do Acre, bem como do modo pelo qual o tema vem se desenvolvendo no Acre como uma estratégia de desenvolvimento sustentável. Baseados nos trabalhos referentes à caça realizados no Acre e em outras regiões amazônicas, fazemos algumas recomendações para prioridades de pesquisa e políticas públicas relacionadas ao uso da fauna silvestre no estado. Wildlife represents an important source of food for people who live in tropical forests, and it is also consumed in these regions? urban areas. Here, we aimed to discuss the topic of hunting through a compilation and review of studies conducted in the state of Acre, as well as an assessment of how hunting has been addressed in Acre as a sustainable development strategy. Based on the previous work related to hunting in Acre and other regions of the Amazon, we make some recommendations for priorities for research and public policies regarding the use of wildlife in the state. La fauna silvestre representa una importante fuente de alimentos para las personas que viven en los bosques tropicales, además de ser bastante consumida en las zonas urbanas de esas regiones. En este trabajo, se objetivó hacer una discusión del tema caza, a través de rescate histórico de los estudios ya realizados en el estado de Acre, así como el modo como el tema se viene desarrollando en el Acre como una estrategia de desarrollo sostenible. Basado en los trabajos referentes a la caza realizados en Acre y en otras regiones Amazónicas hacemos algunas recomendaciones para prioridades de investigación y políticas públicas relacionadas al uso de la fauna silvestre en el estado

    Spatial contrast sensitivity in adolescents with autism spectrum disorders

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    Adolescents with autism spectrum disorders (ASD) and typically developing (TD) controls underwent a rigorous psychophysical assessment that measured contrast sensitivity to seven spatial frequencies (0.5-20 cycles/degree). A contrast sensitivity function (CSF) was then fitted for each participant, from which four measures were obtained: visual acuity, peak spatial frequency, peak contrast sensitivity, and contrast sensitivity at a low spatial frequency. There were no group differences on any of the four CSF measures, indicating no differential spatial frequency processing in ASD. Although it has been suggested that detail-oriented visual perception in individuals with ASD may be a result of differential sensitivities to low versus high spatial frequencies, the current study finds no evidence to support this hypothesis

    Mitochondria dysfunction is associated with long-term cognitive impairment in an animal sepsis mode

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    Background: Several different mechanisms have been proposed to explain long-term cognitive impairment in sepsis survivors. The role of persisting mitochondrial dysfunction is not known. We thus sought to determine whether stimulation of mitochondrial dynamics improves mitochondrial function and long-term cognitive impairment in an experimental model of sepsis. Methods: Sepsis was induced in adult Wistar rats by cecal ligation and perforation (CLP). Animals received intracerebroventricular injections of either rosiglitazone (biogenesis activator), rilmenidine, rapamycin (autophagy activators), or n-saline (sham control) once a day on days 7–9 after the septic insult. Cognitive impairment was assessed by inhibitory avoidance and object recognition tests. Animals were killed 24 h, 3 and 10 days after sepsis with the hippocampus and prefrontal cortex removed to determine mitochondrial function. Results: Sepsis was associated with both acute (24 h) and late (10 days) brain mitochondrial dysfunction. Markers of mitochondrial biogenesis, autophagy and mitophagy were not up-regulated during these time points. Activation of biogenesis (rosiglitazone) or autophagy (rapamycin and rilmenidine) improved brain ATP levels and ex vivo oxygen consumption and the long-term cognitive impairment observed in sepsis survivors. Conclusion: Long-term impairment of brain function is temporally related to mitochondrial dysfunction. Activators of autophagy and mitochondrial biogenesis could rescue animals from cognitive impairment
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