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Cohesive Neighborhoods Where Social Expectations Are Shared May Have Positive Impact On Adolescent Mental Health
Adolescent mental health problems are associated with poor health and well-being in adulthood. This study uses data from a birth cohort of children born in large U.S. cities (N=2,264) to examine whether neighborhood collective efficacy (social cohesion and control) is associated with improvements in adolescent mental health. We find that children who grow up in high collective efficacy neighborhoods experience fewer depressive and anxiety symptoms during adolescence than similar children from low collective efficacy neighborhoods. The magnitude of this neighborhood effect is comparable to the effects of depression prevention programs. Findings do not vary by family or neighborhood income, indicating that neighborhood collective efficacy supports adolescent mental health across diverse populations and urban settings. We recommend greater emphasis on neighborhood environments in individual mental health risk assessments and greater investment in community-based initiatives that strengthen neighborhood social cohesion and control
Identifying High Metallicity M Giants at Intragroup Distances with SDSS
Tidal stripping and three-body interactions with the central supermassive
black hole may eject stars from the Milky Way. These stars would comprise a set
of `intragroup' stars that trace the past history of interactions in our
galactic neighborhood. Using the Sloan Digital Sky Survey DR7, we identify
candidate solar metallicity red giant intragroup stars using color cuts that
are designed to exclude nearby M and L dwarfs. We present 677 intragroup
candidates that are selected between 300 kpc and 2 Mpc, and are either the
reddest intragroup candidates (M7-M10) or are L dwarfs at larger distances than
previously detected.Comment: 8 pages, 6 figures, 1 table (for full version, see
http://astro.phy.vanderbilt.edu/~palladl2), Accepted for publication in A
Magnetic Field Generation in Stars
Enormous progress has been made on observing stellar magnetism in stars from
the main sequence through to compact objects. Recent data have thrown into
sharper relief the vexed question of the origin of stellar magnetic fields,
which remains one of the main unanswered questions in astrophysics. In this
chapter we review recent work in this area of research. In particular, we look
at the fossil field hypothesis which links magnetism in compact stars to
magnetism in main sequence and pre-main sequence stars and we consider why its
feasibility has now been questioned particularly in the context of highly
magnetic white dwarfs. We also review the fossil versus dynamo debate in the
context of neutron stars and the roles played by key physical processes such as
buoyancy, helicity, and superfluid turbulence,in the generation and stability
of neutron star fields.
Independent information on the internal magnetic field of neutron stars will
come from future gravitational wave detections. Thus we maybe at the dawn of a
new era of exciting discoveries in compact star magnetism driven by the opening
of a new, non-electromagnetic observational window.
We also review recent advances in the theory and computation of
magnetohydrodynamic turbulence as it applies to stellar magnetism and dynamo
theory. These advances offer insight into the action of stellar dynamos as well
as processes whichcontrol the diffusive magnetic flux transport in stars.Comment: 41 pages, 7 figures. Invited review chapter on on magnetic field
generation in stars to appear in Space Science Reviews, Springe
CAMP: a useful resource for research on antimicrobial peptides
Antimicrobial peptides (AMPs) are gaining popularity as better substitute to antibiotics. These peptides are shown to be active against several bacteria, fungi, viruses, protozoa and cancerous cells. Understanding the role of primary structure of AMPs in their specificity and activity is essential for their rational design as drugs. Collection of Anti-Microbial Peptides (CAMP) is a free online database that has been developed for advancement of the present understanding on antimicrobial peptides. It is manually curated and currently holds 3782 antimicrobial sequences. These sequences are divided into experimentally validated (patents and non-patents: 2766) and predicted (1016) datasets based on their reference literature. Information like source organism, activity (MIC values), reference literature, target and non-target organisms of AMPs are captured in the database. The experimentally validated dataset has been further used to develop prediction tools for AMPs based on the machine learning algorithms like Random Forests (RF), Support Vector Machines (SVM) and Discriminant Analysis (DA). The prediction models gave accuracies of 93.2% (RF), 91.5% (SVM) and 87.5% (DA) on the test datasets. The prediction and sequence analysis tools, including BLAST, are integrated in the database. CAMP will be a useful database for study of sequence-activity and -specificity relationships in AMPs. CAMP is freely available at http://www.bicnirrh.res.in/antimicrobial
Institutionalised corruption in Indonesian irrigation: An analysis of the upeti system
This article analyzes the internal logic of the upeti system in Indonesian irrigation and brings to light how corruption rules are shaped through complex socio-political relationships reflected in the organizational culture of the irrigation agency. Based on 100 interviews with water sector professionals the article highlights: (1) the importance of social relations in shaping institutionalized corruption, (2) how the upeti system justifies corruption practices as the prevailing social norm, and (3) the need for structural change to eradicate corruption. Illustrating how corruption rules are embedded in project management procedures, with projects highly dependent on donor funding, the article highlights the importance of the issue for international agencies and the need to be more politically grounded in promoting their development agenda
2MASS J01542930+0053266 : A New Eclipsing M-dwarf Binary System
We report on 2MASS J01542930+0053266, a faint eclipsing system composed of
two M dwarfs. The variability of this system was originally discovered during a
pilot study of the 2MASS Calibration Point Source Working Database. Additional
photometry from the Sloan Digital Sky Survey yields an 8-passband lightcurve,
from which we derive an orbital period of 2.6390157 +/- 0.0000016 days.
Spectroscopic followup confirms our photometric classification of the system,
which is likely composed of M0 and M1 dwarfs. Radial velocity measurements
allow us to derive the masses (M_1 = 0.66 +/- 0.03 M_sun; M_2 = 0.62 +/- 0.03
M_sun) and radii (R_1 = 0.64 +/- 0.08 R_sun; R_2 = 0.61 +/- 0.09 R_sun) of the
components, which are consistent with empirical mass-radius relationships for
low-mass stars in binary systems. We perform Monte Carlo simulations of the
lightcurves which allow us to uncover complicated degeneracies between the
system parameters. Both stars show evidence of H-alpha emission, something not
common in early-type M dwarfs. This suggests that binarity may influence the
magnetic activity properties of low-mass stars; activity in the binary may
persist long after the dynamos in their isolated counterparts have decayed,
yielding a new potential foreground of flaring activity for next generation
variability surveys.Comment: 8 figures and 3 tables, accepted for publication in MNRA
The Evolution of Compact Binary Star Systems
We review the formation and evolution of compact binary stars consisting of
white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and
BHs are thought to be the primary astrophysical sources of gravitational waves
(GWs) within the frequency band of ground-based detectors, while compact
binaries of WDs are important sources of GWs at lower frequencies to be covered
by space interferometers (LISA). Major uncertainties in the current
understanding of properties of NSs and BHs most relevant to the GW studies are
discussed, including the treatment of the natal kicks which compact stellar
remnants acquire during the core collapse of massive stars and the common
envelope phase of binary evolution. We discuss the coalescence rates of binary
NSs and BHs and prospects for their detections, the formation and evolution of
binary WDs and their observational manifestations. Special attention is given
to AM CVn-stars -- compact binaries in which the Roche lobe is filled by
another WD or a low-mass partially degenerate helium-star, as these stars are
thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure
Collective irrigation reloaded. Re-collection and re-moralization of water management after privatization in Spain
[EN] In recent decades, water has been subjected to different commodification and de-collectivization processes. Increasingly, this is also affecting collective irrigation Water management. Critical analysis of this privatization and de-collectivization wave in the irrigation sector has mainly focused on neoliberal institutional policies and market-oriented legislation. However, subtly and silently but equally determinant, the adoption of water-saving technologies is fostering the penetration of private enterprise and market-based governance into these hydro social settings. This paper discusses this phenomenon through a case study of the community of Senyera in Valencia, Spain, tracking the privatization and subsequent contestation and re-takeover of water management by irrigation system users. The article shows how privatization removes users' autonomy in the name of common well-being, and increases irrigation costs in a context of little transparency. But the case also highlights users' capacity to re-value and re-signify, their past collective action, remembering and 're-membering to' the collective. Senyera water users critically and reflexively analyse privatization, reconstruct societal relationships around and embedded inside the new technology, and re-collectivize and re-moralize irrigation management in a new hydro social scenario.Support for this research has been partially provided by the project INIA RTA2014-00050-00-00 from the Spanish Ministry of Economy and Competitiveness, partially financed with ERDF funds.Sanchis Ibor, C.; Boelens, R.; García Molla, M. (2017). Collective irrigation reloaded. Re-collection and re-moralization of water management after privatization in Spain. Geoforum. 87:38-47. https://doi.org/10.1016/j.geoforum.2017.10.002S38478
Primary rat sertoli and interstitial cells exhibit a differential response to cadmium
Two cell types central to the support of spermatogenesis, the Sertoli cell and the interstitial (Leydig) cell, were isolated from the same cohort of young male rats and challenged with cadmium chloride to compare their susceptibility to the metal. Both cell types were cultured under similar conditions, and similar biochemical endpoints were chosen to minimize experimental variability. These endpoints include the uptake of 109 Cd, reduction of the vital tetrazolium dye MTT, incorporation of 3 H-leucine, change in heat-stable cadmium binding capacity, and production of lactate. Using these parameters, it was observed that the Sertoli cell cultures were adversely affected in a dose-and time-dependent manner, while the interstitial cell cultures, treated with identical concentrations of CdCl 2 , were less affected. The 72-hr LC 50 's for Sertoli cells and interstitial cells were 4.1 and 19.6 μM CdCl 2 , respectively. Thus, different cell populations within the same tissue may differ markedly in susceptibility to a toxicant. These in vitro data suggest that the Sertoli cell, in relation to the interstitium, is particularly sensitive to cadmium. Because the Sertoli cell provides functional support for the seminiferous epithelium, the differential sensitivity of this cell type may, in part, explain cadmium-induced testicular dysfunction, particularly at doses that leave the vascular epithelium intact.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42554/1/10565_2004_Article_BF00135027.pd
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