Stellar models and isochrones from low-mass to massive stars including pre-main sequence phase with accretion

Grids of stellar models are useful tools to derive the properties of stellar clusters, in particular young clusters hosting massive stars, and to provide information on the star formation process in various mass ranges. Because of their short evolutionary timescale, massive stars end their life while their low-mass siblings are still on the pre-main sequence (pre-MS) phase. Thus the study of young clusters requires consistent consideration of all the phases of stellar evolution. But despite the large number of grids that are available in the literature, a grid accounting for the evolution from the pre-MS accretion phase to the post-MS phase in the whole stellar mass range is still lacking. We build a grid of stellar models at solar metallicity with masses from 0.8 $M_\odot$ to 120 $M_\odot$, including pre-MS phase with accretion. We use the {\sc genec} code to run stellar models on this mass range. The accretion law is chosen to match the observations of pre-MS objects on the Hertzsprung-Russell diagram. We describe the evolutionary tracks and isochrones of our models. The grid is connected to previous MS and post-MS grids computed with the same numerical method and physical assumptions, which provides the widest grid in mass and age to date. Numerical tables of our models and corresponding isochrones are available online

Science with an ngVLA: Resolving the Radio Complexity of EXor and FUor-type Systems with the ngVLA

Episodic accretion may be a common occurrence in the evolution of young pre-main sequence stars and has important implications for our understanding of star and planet formation. Many fundamental aspects of what drives the accretion physics, however, are still unknown. The ngVLA will be a key tool in understanding the nature of these events. The high spatial resolution, broad spectral coverage, and unprecedented sensitivity will allow for the detailed analysis of outburst systems. The proposed frequency range of the ngVLA allows for observations of the gas, dust, and non-thermal emission from the star and disk.Comment: 8 pages, 1 figure, To be published in the ASP Monograph Series, "Science with a Next-Generation VLA", ed. E. J. Murphy (ASP, San Francisco, CA

Mitochondrial DNA Polymorphism A4917G Is Independently Associated with Age-Related Macular Degeneration

The objective of this study was to determine if MTND2*LHON4917G (4917G), a specific non-synonymous polymorphism in the mitochondrial genome previously associated with neurodegenerative phenotypes, is associated with increased risk for age-related macular degeneration (AMD). A preliminary study of 393 individuals (293 cases and 100 controls) ascertained at Vanderbilt revealed an increased occurrence of 4917G in cases compared to controls (15.4% vs.9.0%, p = 0.11). Since there was a significant age difference between cases and controls in this initial analysis, we extended the study by selecting Caucasian pairs matched at the exact age at examination. From the 1547 individuals in the Vanderbilt/Duke AMD population association study (including 157 in the preliminary study), we were able to match 560 (280 cases and 280 unaffected) on exact age at examination. This study population was genotyped for 4917G plus specific AMD-associated nuclear genome polymorphisms in CFH, LOC387715 and ApoE. Following adjustment for the listed nuclear genome polymorphisms, 4917G independently predicts the presence of AMD (OR = 2.16, 95%CI 1.20–3.91, p = 0.01). In conclusion, a specific mitochondrial polymorphism previously implicated in other neurodegenerative phenotypes (4917G) appears to convey risk for AMD independent of recently discovered nuclear DNA polymorphisms

EXPERIENCES OF DRUG USERS IN IIA CLASS JAIL YOGYAKARTA

United Nations Office on Drugs and Crime (UNODC) estimated that about 149-272 million people or 3.3 % - 6.1 % of world population aged 15-64 years used drugs (even once) during their life time. This estimation will increase with time (BNN, 2011). The number of prisoners suffering HIV/AIDS in recent years were increasing as well if compared to its numbers in the year 2011 from 787 people to 1042 people. It was estimated that in the year 2015, the number of drug users in Indonesia would increase to 5.8 million people, since the number of drug users at the present time were reached 4 million people. For the time being, in Yogyakarta second A class drug jail , the number of drug users were 256 people; this number were constant; its mean that if there was prisoner got his / her freedom, another prisoner was incoming. Data from BNN in August 2013 years, 70% of 4 million drug users in Indonesia were workers (productive aged). Aim; To discovered population research experiences that cause them used drugs and depend on its. Research method: This was qualitative research with phenomenological approach. Data gathering technique were deep interview and FGD toward 30 respondents. Data were analyzed using reduction, data display, and conclusion drawing/verification. The majority of respondents mentioned that they used drugs because of they wanted to know and the influence of friends. Drugs, kinds of sabu, used to increase energy and ganja were used to obtain peacefulness. Drugs users wanted to use its forever; therefore, they wanted to stop because of punishment to be in jail not because of the drugs had negative effects to the body. The majority of respondents mentioned that to stop using drugs must be self motivated; on the contrary, the obstacle to stop using drugs because of missing sensation to use it. They named it suggest. Using drugs were conducted by research population because of environmental influence, to increase energy and to obtain peacefulness. Keywords : The experiences of drug use

G-quadruplex formation within the promoter of the KRAS proto-oncogene and its effect on transcription

In human and mouse, the promoter of the KRAS gene contains a nuclease hypersensitive polypurine–polypyrimidine element (NHPPE) that is essential for transcription. An interesting feature of the polypurine G-rich strand of NHPPE is its ability to assume an unusual DNA structure that, according to circular dichroism (CD) and DMS footprinting experiments, is attributed to an intramolecular parallel G-quadruplex, consisting of three G-tetrads and three loops. The human and mouse KRAS NHPPE G-rich strands display melting temperature of 64 and 73°C, respectively, as well as a K(+)-dependent capacity to arrest DNA polymerase. Photocleavage and CD experiments showed that the cationic porphyrin TMPyP4 stacks to the external G-tetrads of the KRAS quadruplexes, increasing the T(m) by ∼20°C. These findings raise the intriguing question that the G-quadruplex formed within the NHPPE of KRAS may be involved in the regulation of transcription. Indeed, transfection experiments showed that the activity of the mouse KRAS promoter is reduced to 20% of control, in the presence of the quadruplex-stabilizing TMPyP4. In addition, we found that G-rich oligonucleotides mimicking the KRAS quadruplex, but not the corresponding 4-base mutant sequences or oligonucleotides forming quadruplexes with different structures, competed with the NHPPE duplex for binding to nuclear proteins. When vector pKRS-413, containing CAT driven by the mouse KRAS promoter, and KRAS quadruplex oligonucleotides were co-transfected in 293 cells, the expression of CAT was found to be downregulated to 40% of the control. On the basis of these data, we propose that the NHPPE of KRAS exists in equilibrium between a double-stranded form favouring transcription and a folded quadruplex form, which instead inhibits transcription. Such a mechanism, which is probably adopted by other growth-related genes, provides useful hints for the rational design of anticancer drugs against the KRAS oncogene

Assessment of function and clinical utility of alcohol and other drug web sites: An observational, qualitative study

Background The increasing popularity and use of the internet makes it an attractive option for providing health information and treatment, including alcohol/other drug use. There is limited research examining how people identify and access information about alcohol or other drug (AOD) use online, or how they assess the usefulness of the information presented. This study examined the strategies that individuals used to identify and navigate a range of AOD websites, along with the attitudes concerning presentation and content. Methods Members of the general community in Brisbane and Roma (Queensland, Australia) were invited to participate in a 30-minute search of the internet for sites related to AOD use, followed by a focus group discussion. Fifty one subjects participated in the study across nine focus groups. Results Participants spent a maximum of 6.5 minutes on any one website, and less if the user was under 25 years of age. Time spent was as little as 2 minutes if the website was not the first accessed. Participants recommended that AOD-related websites should have an engaging home or index page, which quickly and accurately portrayed the site’s objectives, and provided clear site navigation options. Website content should clearly match the title and description of the site that is used by internet search engines. Participants supported the development of a portal for AOD websites, suggesting that it would greatly facilitate access and navigation. Treatment programs delivered online were initially viewed with caution. This appeared to be due to limited understanding of what constituted online treatment, including its potential efficacy. Conclusions A range of recommendations arise from this study regarding the design and development of websites, particularly those related to AOD use. These include prudent use of text and information on any one webpage, the use of graphics and colours, and clear, uncluttered navigation options. Implications for future website development are discussed