988 research outputs found
Sex differences in HIV effects on visual memory among substance-dependent individuals
HIVâs effects on episodic memory have not been compared systematically between male and female substance-dependent individuals. We administered the Brief Visuospatial Memory TestâRevised (BVMTâR) to 280 substance-dependent HIV+ and HIVâ men and women. Groups were comparable on demographic, substance use, and comorbid characteristics. There were no significant main effects of sex or HIV serostatus on BVMTâR performance, but HIV+ women performed significantly more poorly on delayed recall. This effect was most prominent among cocaine-dependent HIV+ women. Our findings are consistent with recent speculation that memory impairment may be more common among HIV+ women, particularly those with a history of cocaine dependence
A Bayesian technique for improving the sensitivity of the atmospheric neutrino L/E analysis
This paper outlines a method for improving the precision of atmospheric
neutrino oscillation measurements. One experimental signature for these
oscillations is an observed deficit in the rate of charged-current
interactions with an oscillatory dependence on , where
is the neutrino propagation distance, and is the neutrino
energy. For contained-vertex atmospheric neutrino interactions, the
resolution varies significantly from event to event. The
precision of the oscillation measurement can be improved by incorporating
information on resolution into the oscillation analysis. In
the analysis presented here, a Bayesian technique is used to estimate the
resolution of observed atmospheric neutrinos on an
event-by-event basis. By separating the events into bins of
resolution in the oscillation analysis, a significant improvement in
oscillation sensitivity can be achieved.Comment: 12 pages, 7 figures, submitted to Nucl. Instrum. Methods A,
accompanies arXiv:1208.2915 [hep-ex
Plant Growth-Promoting Activity of Bacteria Isolated from Asian Rice (\u3cem\u3eOryza sativa\u3c/em\u3e L.) Depends on Rice Genotype
Asian rice is one of the most important crops because it is a staple food for almost half of the worldâs population. To have production of rice keep pace with a growing world population, it is anticipated that the use of fertilizers will also need to increase, which may cause environmental damage through runoff impacts. An alternative strategy to increase crop yield is the use of plant growth-promoting bacteria. Thousands of microbial species can exist in association with plant roots and shoots, and some are critical to the plantâs survival. We isolated 140 bacteria from two distantly related rice accessions and investigated whether their impact on the growth of four different rice accessions. The bacterial isolates were screened for their ability to solubilize phosphate, a known plant growth-promoting characteristic, and 25 isolates were selected for further analysis. These 25 phosphate-solubilizing isolates were also able to produce other potentially growth-promoting factors. Five of the most promising bacterial isolates were chosen for whole-genome sequencing. Four of these bacteria, isolates related to Pseudomonas mosselii, a Microvirga sp., Paenibacillus rigui, and Paenibacillus graminis, improved root and shoot growth in a rice genotype-dependent manner. This indicates that while bacteria have several known plant growth-promoting functions, their effects on growth parameters are rice genotype dependent and suggest a close relationship between plants and their microbial partners
The Impact of Perspective in Identifying and Responding to Potential Sexual Misconduct: A Study of University Students
Recent events have demonstrated a divergent understanding of sexual harassment and other forms of sexual misconduct. Although sociocultural standards regarding sexual misconduct have changed over time, including improved social and workplace standards and protections, it is clear that not everyone views these events through the same lens. The lens is even less clear when potential misconduct is viewed from the distinct perspectives of a âvictimâ and a âperpetrator.â We surveyed 424 undergraduate and graduate students at Indiana University Kokomo to identify the impact of perspective and various sociodemographic characteristics that may influence perceptions of what is, and is not, sexual misconduct. In addition, we examined if these factors also influence opinions on the severity of response toward this misconduct. Students completed a gender-neutral survey that presented eight potential sexualmisconduct scenarios in a first-person narrative. In each scenario, the fact pattern was identical, but some surveys were in the perspective of the âvictimâ and some were in the perspective of the âperpetrator.â We find that perspective matters, as do reported preconceived attitudes toward sexual misconduct. We also find preliminary evidence that the impact of perspective and the severity of the response may depend on whether the misconduct occurs in an organizational setting, in a date setting, or without a distinct victim
Maximizing Minimum Pressure in Fluid Dynamic Bearings of Hard Disk Drives
We focus on the central spindle which supports the rotating magnetic platters which hold all of the data. The spindle must operate with great precision and stability at high rotational speeds. Design practice has converged on oil-lubricated hydrodynamic journal bearings as the most common choice for spindles. That is, a layer of viscous oil separates a rotating shaft (the bearing) from the fixed outer sleeve (the journal). In hard drives, it is very important for the shaft to be centered within the sleeve. Plain journal bearings (i.e. both surfaces are circular cylinders) are unstable to perturbations that push the shaft off-center. It was found that this stability problem can be overcome by cutting diagonal grooves into the journal in a pattern called a herring-bone. Another consequence of this design is that very high pressures are generated by the grooves as they drive the oil to the middle of the bearing, away from the top/bottom ends of the spindle. This pumping action generally works to oppose leakage out of the bearing.
We examine how choices for the groove pattern can influence the key properties of the bearing. The focus is to understand the effect of the groove geometry on the pumping action. In particular the undesirable behavior caused by the low pressures created near the top/bottom ends of the bearing which, under many conditions, may result in the pressure becoming negative, relative to atmospheric pressure. Negative pressure can result in cavitation or, when it occurs near an air-oil interface, can cause air to be ingested and hence create bubbles. Any bubbles in the oil can corrupt the lubricating layer in the bearing and, as they are created and collapse, can cause significant undesirable vibrations. The negative pressures have therefore been identified as one of the key problems in design of hard disk drive bearings.
We will use numerical computations and some analysis to show that by modifying the groove geometry we can reduce the negative pressure while retaining good stability characteristics
Japan: A case study of national âreadinessâ for regenerative medicine
This article focuses on Japan, as a country with a strong and distinctive strategy for delivering RM, and outlines efforts to build regenerative readines
Radiative Generation of the LMA Solution from Small Solar Neutrino Mixing at the GUT Scale
We show that in see-saw models with small or even vanishing lepton mixing
angle , maximal , zero and zero CP
phases at the GUT scale, the currently favored LMA solution of the solar
neutrino problem can be obtained in a rather natural way by Renormalization
Group effects. We find that most of the running takes place in the energy
ranges above and between the see-saw scales, unless the charged lepton Yukawa
couplings are large, which would correspond to a large in the
Minimal Supersymmetric Standard Model (MSSM). The Renormalization Group
evolution of the solar mixing angle is generically larger than
the evolution of and . A large enhancement occurs
for an inverted mass hierarchy and for a regular mass hierarchy with . We present numerical examples of the evolution of the
lepton mixing angles in the Standard Model and the MSSM, in which the current
best-fit values of the LMA mixing angles are produced with vanishing solar
mixing angle at the GUT scale.Comment: 10 pages, 6 figures; reference added, minor changes in the text;
results unchanged; final version to appear in JHE
Migration and risk of intellectual disability with and without autism:A population-based cohort study
Objective
To investigate whether parental migration, parental region of origin, timing of child's birth in relation to maternal migration and parental reason for migration are associated with intellectual disability (ID) with and without autism.
Methods
We used a register-based cohort of all individuals aged 0â17 years in Stockholm County during 2001â2011. General estimating equation logistic model and additionally sibling comparison were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The models were adjusted for child's sex and birth year and parental age at child's birth, and additionally for migrant-specific variables in the analyses including only children with migrant parent(s).
Results
Within the eligible sample of 670,098 individuals, 3781 (0.6%) had ID with autism, and 5076 (0.8%) had ID without autism. Compared with children with Swedish-born parents, children with both parents born abroad had an increased risk of ID with autism (OR = 1.6, CI 1.5â1.8) and ID without autism (OR = 1.9, CI 1.7â2.0). Among these children with both parents born abroad, it was protective of ID with autism when the child's birth occurred before and later than four years after maternal migration, which was replicated in the sibling comparison. The associations with both conditions were more pronounced with parental origin in regions comprising low- and middle-income countries and with reasons other than work or study.
Conclusions
Parental migration is associated with ID regardless of co-occurrence of autism. Our results indicate an association between environmental factors during pregnancy related to migration and offspring ID with autism, although further confirmative studies are needed
Supergravity at Colliders
We consider supersymmetric theories where the gravitino is the lightest
superparticle (LSP). Assuming that the long-lived next-to-lightest
superparticle (NSP) is a charged slepton, we investigate two complementary ways
to prove the existence of supergravity in nature. The first is based on the NSP
lifetime which in supergravity depends only on the Planck scale and the NSP and
gravitino masses. With the gravitino mass inferred from kinematics, the
measurement of the NSP lifetime will test an unequivocal prediction of
supergravity. The second way makes use of the 3-body NSP decay. The angular and
energy distributions and the polarizations of the final state photon and lepton
carry the information on the spin of the gravitino and on its couplings to
matter and radiation.Comment: 13 pages, 11 figures; v2: 3 references added, to appear in Physics
Letters
Short-term social memory in the laboratory rat: its susceptibility to disturbance.
Short-term social memory in the laboratory rat: its susceptibility to disturbance
- âŚ