A submillimeter search for pre- and proto-brown dwarfs in Chamaeleon II

Context. Chamaeleon II molecular cloud is an active star forming region that offers an excellent opportunity for studying the formation of brown dwarfs in the southern hemisphere. Aims. Our aims are to identify a population of pre- and proto- brown dwarfs (5 sigma mass limit threshold of ~0.015 Msun) and provide information on the formation mechanisms of substellar objects. Methods. We performed high sensitivity observations at 870 microns using the LABOCA bolometer at the APEX telescope towards an active star forming region in Chamaeleon II. The data are complemented with an extensive multiwavelength catalogue of sources from the optical to the far-infrared to study the nature of the LABOCA detections. Results. We detect fifteen cores at 870 microns, and eleven of them show masses in the substellar regime. The most intense objects in the surveyed field correspond to the submillimeter counterparts of the well known young stellar objects DK Cha and IRAS 12500-7658. We identify a possible proto-brown dwarf candidate (ChaII-APEX-L) with IRAC emission at 3.6 and 4.5 microns. Conclusions. Our analysis indicates that most of the spatially resolved cores are transient, and that the point-like starless cores in the sub-stellar regime (with masses between 0.016 Msun and 0.066 Msun) could be pre-brown dwarfs cores gravitationally unstable if they have radii smaller than 220 AU to 907 AU (1.2" to 5" at 178 pc) respectively for different masses. ALMA observations will be the key to reveal the energetic state of these pre-brown dwarfs candidates.Comment: 11 pages, 6 figure

The Spatial Distribution of Star Formation in the Solar Neighbourhood: Do all stars form in clusters?

We present a global study of low mass, young stellar object (YSO) surface densities in nearby (< 500 pc) star forming regions based on a comprehensive collection of Spitzer Space Telescope surveys. We show that the distribution of YSO surface densities in the solar neighbourhood is a smooth distribution, being adequately described by a lognormal function from a few to 10^3 YSOs per pc^2, with a peak at 22 stars/pc^2 and a dispersion of 0.85. We do not find evidence for multiple discrete modes of star-formation (e.g. clustered and distributed). Comparing the observed surface density distribution to previously reported surface density threshold definitions of clusters, we find that the fraction of stars in clusters is crucially dependent on the adopted definitions, ranging from 40 to 90%. However, we find that only a low fraction (< 26%) of stars are formed in dense environments where their formation/evolution (along with their circumstellar disks and/or planets) may be affected by the close proximity of their low-mass neighbours.Comment: 6 pages, 2 figures, MNRAS letters, accepte

The clinical profile ,severity and outcome of cases of seropositive dengue fever over 2012, 2013 & 2014: A year wise retrospective analysis

BACKGROUND: The global incidence of Dengue fever has considerably increased over the past few decades. The mortality and morbidity is alarmingly increasing. Increased awareness and alertness among Health authorities and personnel lead to detection of large number of cases. Dengue has risen from being an epidemic to being a source of grave social concern in the district of Trichy. This study covers the clinical presentation, investigations and outcome of patients with Dengue. METHODS: A retrospective study on 50 patients per year from 2012-2014 on Dengue fever at the Mahatma Gandhi Memorial Government Hospital, Trichy aims at documenting the presentation and course of illness over 3 years.The data has been collected from medical records department using a structured questionaaire. The data is statistically analysed and arrived at conclusions using SPSS. PRINCIPAL FINDINGS: There is no gender predilection in dengue fever.Majority had fever for less than a week. Those with varied manifestations from Dengue Fever to Dengue Shock Syndrome with or without comorbidities along with complications can have good prognostic outcome if treated promptly

Assessment of knowledge, attitude and practice of over-the-counter drugs and dietary supplements among non-healthcare college students in Chitradurga

Background: The market for OTC drugs and dietary supplements is rapidly growing. However, there exists a lack of adequate awareness among the general public regarding the advantages and potential drawbacks associated with these products, particularly among the younger generation, who heavily rely on the internet for information. Therefore, this study sought to assess the knowledge, attitude and practice of college students regarding OTC drugs and dietary supplements, including prevalence and associated factors. Methods: A prospective interventional study with 306 participants was conducted. Data were collected using a self-designed and pre-validated questionnaire and analysed using Statistical Package for the Social Sciences (SPSS) version 28. Descriptive and inferential (T-test) statistics were use. Results: The prevalence of usage of OTC drugs and DSs was found to be 98.4% and 61.4% respectively. Easy accessibility (42.2%), safe and well tolerable (32.5%) were the main factors that influenced them to turn to SM with OTC drugs. The respondent’s preference for DSs was primarily driven by their desire to maintain good health (33.6%). Internet (22.2%) and healthcare professionals (21.9%) were the two most reported sources that students relied on to obtain information about DSs. The result revealed poor knowledge and a positive attitude towards OTC drugs and DSs among all participants. Conclusions: A high prevalence of self-medication with OTC drugs and dietary supplements use was highlighted. Notable issues and improper practices were recognized. The findings indicate a need for education to enhance knowledge about OTC drugs and DSs and to encourage safe practices

Multidimensional evaluation of mutual funds using performance ratios: a critical examination of technology sector mutual funds in India

Over the years, a number of performance indicators have been developed and used to assess the performance of mutual funds. The choice of these performance measures completely rests on the perception of the investor as to which measure conveys the information sought after by the investor and which information the investor considers would be meaningful in deciding the fate of his investments. Objective & Methodology: To evaluate the risk and return of selected technology sector mutual funds and to analyse the composite information conveyed by Sharpe’s ratio, Treynor’s ratio, upside and downside capture ratios. Results & Discussion: When the funds were analysed using Sharpe ratio, Treynor’s ratio upside capture ratio and downside capture ratio, the funds that performed the best in consideration to a particular measure may not be termed best when analysed with another performance gauges stressing on the fact that all the ratios should be analysed with an integrated perspective to derive any underlying information on the performance of the fund and that the choice of the benchmark which stands as a basis to assess performance of the fund is crucial

Early predictors of impaired social functioning in male rhesus macaques (Macaca mulatta)

Autism spectrum disorder (ASD) is characterized by social cognition impairments but its basic disease mechanisms remain poorly understood. Progress has been impeded by the absence of animal models that manifest behavioral phenotypes relevant to ASD. Rhesus monkeys are an ideal model organism to address this barrier to progress. Like humans, rhesus monkeys are highly social, possess complex social cognition abilities, and exhibit pronounced individual differences in social functioning. Moreover, we have previously shown that Low-Social (LS) vs. High-Social (HS) adult male monkeys exhibit lower social motivation and poorer social skills. It is not known, however, when these social deficits first emerge. The goals of this study were to test whether juvenile LS and HS monkeys differed as infants in their ability to process social information, and whether infant social abilities predicted later social classification (i.e., LS vs. HS), in order to facilitate earlier identification of monkeys at risk for poor social outcomes. Social classification was determined for N = 25 LS and N = 25 HS male monkeys that were 1–4 years of age. As part of a colony-wide assessment, these monkeys had previously undergone, as infants, tests of face recognition memory and the ability to respond appropriately to conspecific social signals. Monkeys later identified as LS vs. HS showed impairments in recognizing familiar vs. novel faces and in the species-typical adaptive ability to gaze avert to scenes of conspecific aggression. Additionally, multivariate logistic regression using infant social ability measures perfectly predicted later social classification of all N = 50 monkeys. These findings suggest that an early capacity to process important social information may account for differences in rhesus monkeys’ motivation and competence to establish and maintain social relationships later in life. Further development of this model will facilitate identification of novel biological targets for intervention to improve social outcomes in at-risk young monkeys

OPTIMIZATION OF ANNEALING TEMPERATURE FOR COI GENE AMPLIFICATION ON EXTRIMOPHIL FISH USING REAL-TIME PCR

Extremophilic fish require genetic characterization to determine the identity of their species, their kinship, and the potential for genetic variation due to extreme environmental adaptation. DNA barcoding using Fish-F2 and Fish-R2 primers at an annealing temperature of 52oC for 15 seconds showed qualitative failure results in most fish species. For this reason, optimizing the annealing temperature in the PCR process is necessary to obtain DNA bands that correlate with successful identification. Fish samples were obtained from Ruai Silip, Bangka Island, Membalong, Belitung Island, and Way Kanan, Lampung, Sumatra Island. The annealing temperature optimization was set at 50, 50.4, 51.1, 52.3, 53.7, 54.8, 55.5, and 56°C. Five species of extremophile fish were tested, namely Brevibora sp, Barbodes binotatus, Rasbora bankanensis, Anabas testudineus, and Aplocheilus panchax. Extremophile fish showed differences in the appearance of DNA bands in PCR with different annealing temperatures. Brevibora sp showed a visualization of DNA bands at 54.8°C, Barbodes binotatus at 53.7, 54.8, 55.5, and 56°C, Anabas testudineus at 50 and 50.4°C, and Aplocheilus panchax produced clearly visible band on annealing temperatures

Mechanisms of photoreceptor death and survival in mammalian retina

The mammalian retina, like the rest of the central nervous system, is highly stable and can maintain its structure and function for the full life of the individual, in humans for many decades. Photoreceptor dystrophies are instances of retinal instability. Many are precipitated by genetic mutations and scores of photoreceptor-lethal mutations have now been identified at the codon level. This review explores the factors which make the photoreceptor more vulnerable to small mutations of its proteins than any other cell of the body, and more vulnerable to environmental factors than any other retinal neurone. These factors include the highly specialised structure and function of the photoreceptors, their high appetite for energy, their self-protective mechanisms and the architecture of their energy supply from the choroidal circulation. Particularly important are the properties of the choroidal circulation, especially its fast flow of near-arterial blood and its inability to autoregulate. Mechanisms which make the retina stable and unstable are then reviewed in three different models of retinal degeneration, retinal detachment, photoreceptor dystrophy and light damage. A two stage model of the genesis of photoreceptor dystrophies is proposed, comprising an initial "depletion" stage caused by genetic or environmental insult and a second "late" stage during which oxygen toxicity damages and eventually destroys any photoreceptors which survive the initial depletion. It is a feature of the model that the second "late" stage of retinal dystrophies is driven by oxygen toxicity. The implications of these ideas for therapy of retinal dystrophies are discussed

The 69 {μμ}m forsterite band in spectra of protoplanetary disks. Results from the Herschel DIGIT programme

Context. We have analysed far-infrared spectra of 32 circumstellar disks around Herbig Ae/Be and T Tauri stars obtained within the Herschel key programme Dust, Ice and Gas in Time (DIGIT). The spectra were taken with the Photodetector Array Camera and Spectrometer (PACS) on board the Herschel Space Observatory. In this paper we focus on the detection and analysis of the 69 {$μ$}m emission band of the crystalline silicate forsterite. Aims: This work aims at providing an overview of the 69 {$μ$}m forsterite bands present in the DIGIT sample. We use characteristics of the emission band (peak position and FWHM) to derive the dust temperature and to constrain the iron content of the crystalline silicates. With this information, constraints can be placed on the spatial distribution of the forsterite in the disk and the formation history of the crystalline grains. Methods: The 69 {$μ$}m forsterite emission feature is analysed in terms of position and shape to derive the temperature and composition of the dust by comparison to laboratory spectra of that band. The PACS spectra are combined with existing Spitzer IRS spectra and we compare the presence and strength of the 69 {$μ$}m band to the forsterite bands at shorter wavelengths. Results: A total of 32 disk sources have been observed. Out of these 32, 8 sources show a 69 {$μ$}m emission feature that can be attributed to forsterite. With the exception of the T Tauri star AS 205, all of the detections are for disks associated with Herbig Ae/Be stars. Most of the forsterite grains that give rise to the 69 {$μ$}m bands are found to be warm (~{}100-200 K) and iron-poor (less than ~{}2% iron). AB Aur is the only source where the emission cannot be fitted with iron-free forsterite requiring approximately 3-4% of iron. Conclusions: Our findings support the hypothesis that the forsterite grains form through an equilibrium condensation process at high temperatures. The large width of the emission band in some sources may indicate the presence of forsterite reservoirs at different temperatures. The connection between the strength of the 69 and 33 {$μ$}m bands shows that at least part of the emission in these two bands originates fom the same dust grains. We further find that any model that can explain the PACS and the Spitzer IRS observations must take the effects of a wavelength dependent optical depth into account. We find weak indications of a correlation of the detection rate of the 69 {$μ$}m band with the spectral type of the host stars in our sample. However, the sample size is too small to obtain a definitive result. Appendix A is available in electronic form at http://www.aanda.or