449 research outputs found
Earth resources evaluation for New Mexico by LANDSAT-2
The author has identified the following significant results. The Middle Rio Grande project has not yet progressed to the point where mineral exploration sites can be chosen; however, there does appear to be some correlation between the known structure and mineral deposits and the LANDSAT lineament map. A circular feature identified in the southern Magdalena Mountains on LANDSAT-1 imagery agrees well with the location of a newly proposed caldron complex. Several recognized and unrecognized circular features were identified on imagery of the Mogollon-Datil volcanic field. A check of aeromagnetic maps for New Mexico found that the circular features on the LANDSAT imagery showed up as areas of generally high magnetic intensity
Diffusion of stochastic magnetic field lines in a confined plasma using the generalized mapping
The evolution of stochastic magnetic field lines has been studied numerically. Also, we have studied the transition from partial stochasticity to global stochasticity of magnetic field lines. We have developed the analytical calculations of diffusion coefficient of magnetic field lines through magnetic surfaces using the Fourier paths technique. The magnetic field lines are described by the generalized mapping. A comparison between our analytical and numerical calculations has been done.The evolution of stochastic magnetic field lines has been studied numerically. Also, we have studied the transition from partial stochasticity to global stochasticity of magnetic field lines. We have developed the analytical calculations of diffusion coefficient of magnetic field lines through magnetic surfaces using the Fourier paths technique. The magnetic field lines are described by the generalized mapping. A comparison between our analytical and numerical calculations has been done
Electron-loss and target ionization cross sections for water vapor by 20-150 keV neutral atomic hydrogen impact
A complete set of cross sections is reported for the ionization of water
molecules by neutral atomic hydrogen impact at velocities of the order of the
Bragg peak. The measured relative cross sections are normalized by comparison
with proton impact results for the same target conditions and previous absolute
data. Event by event coincidence analysis of the product ions and the
projectile enables partial cross sections for target ionization and target plus
projectile ionization to be determined, as well as total cross sections for
electron loss reactions.Comment: To be published in Chemical Physics Letter
Correlates of condom use in a sample of MSM in Ecuador
BACKGROUND: In Ecuador, the prevalence of HIV in the general population is approximately 0.3%. However, up to 17% prevalence has been reported among specific groups of homosexual and bisexual men. The objective of this study is to explore correlates of condom use among men who have sex with men (MSM) across eight cities in Ecuador. METHODS: A cross-sectional survey design was used. A questionnaire including variables on sexual behaviour, demographics, and socio-economic characteristics was distributed to a sample of MSM in eight Ecuadorian cities. RESULTS: Information was obtained for 2,594 MSM across the eight cities. The largest subcategory of self-identification was active bisexuals (35%), followed by those who described themselves as "hombrados" (masculine gays, 22%). The mean age was 25 years, and the majority were unmarried (78%), with a median of 10 years of schooling (IQR 7 – 12). Regarding condom use, 55% of those interviewed had unprotected penetrative sex with each of their last three partners, and almost 25% had never used a condom. The most important correlates of condom use were single status, high life-skills rating, and high socio-economic status (RP 5.45, 95% CI 4.26 – 6.37; RP 1.84, 95% CI 1.79 – 1.86, and RP 1.20, 95% CI 1.01 – 1.31, respectively). CONCLUSION: Our data illustrate the urgent need for targeted HIV-prevention programs for MSM populations in Ecuador. MSM have the highest HIV prevalence in the country, and condom use is extremely low. It is imperative that prevention strategies be re-evaluated and re-prioritized to more effectively respond to the Ecuadorian epidemic
A FIRST-AND SECOND-ORDER TURBULENCE MODELS IN HYDROGEN NON-PREMIXED FLAME
ABSTRACT The mathematical modelling of turbulent flames is a difficult task due to the intense coupling between turbulent transport processes and chemical kinetics. The model presented within this paper is focused on the turbulence-chemistry interaction. The topic of this study is the numerical simulation of turbulent non-premixed hydrogen flame with different turbulent models in order to invest gate their predictive capability. The two turbulent models are compared: the (k-ε) model with a limited Pope's correction and the Reynolds stress model (RSM). The predictions are validated against experimental data provided by Raman and laser Doppler anemometry (LDA) measurements for a turbulent jet hydrogen-air diffusion flame. The turbulence-chemistry interaction is handled with flame let approach. Simulations of test cases with simple geometries verify the developed model and compare favourably with results of earlier investigations that employed both (k-ε) and RSM closures with the CMC and PDF approache
Critical Review of Theoretical Models for Anomalous Effects (Cold Fusion) in Deuterated Metals
We briefly summarize the reported anomalous effects in deuterated metals at
ambient temperature, commonly known as "Cold Fusion" (CF), with an emphasis on
important experiments as well as the theoretical basis for the opposition to
interpreting them as cold fusion. Then we critically examine more than 25
theoretical models for CF, including unusual nuclear and exotic chemical
hypotheses. We conclude that they do not explain the data.Comment: 51 pages, 4 Figure
Navigation Patterns in Ederly During Multitasking in Virtual Environnment
Cognitive assessment and screening can be realized with virtual environments (VE). These VE reproduce ecological situation and give an overview of participants difficulties through scoring systems. The most variables used to qualify participants performance are number of errors and time completion. These variables are link to cognition and navigation skill in VEs. We assessed navigation of adult and elderly in a multitasking VE. Navigation patterns were elaborate with diagram to visually detect differences between the two age groups. Elderly have poorer performance than adults
Minimum information and guidelines for reporting a Multiplexed Assay of Variant Effect
Multiplexed Assays of Variant Effect (MAVEs) have emerged as a powerful
approach for interrogating thousands of genetic variants in a single
experiment. The flexibility and widespread adoption of these techniques across
diverse disciplines has led to a heterogeneous mix of data formats and
descriptions, which complicates the downstream use of the resulting datasets.
To address these issues and promote reproducibility and reuse of MAVE data, we
define a set of minimum information standards for MAVE data and metadata and
outline a controlled vocabulary aligned with established biomedical ontologies
for describing these experimental designs
Are symptoms of insomnia in primary care associated with subsequent onset of dementia? A matched retrospective case-control study
Objective: There is evidence from neuroimaging studies of an association between insomnia and early dementia biomarkers, but observational studies have so far failed to show a clear association between insomnia and the later development of dementia. We investigated the association between dementia diagnosis and recording of insomnia symptoms 5-10 years earlier in primary care.
Method: A case-control study using data from the Clinical Practice Research Datalink. 15,209 cases with dementia (either Alzheimer's, vascular, mixed or non-specific subtypes) at least 65 years old at time of diagnosis, were matched with the same number of controls on year of birth and gender. We ascertained the presence of insomnia symptoms during a five-year period starting 10 years before the index date. Odds ratios for developing dementia were estimated using logistic regression after controlling for hypnotic exposure and physical and mental health comorbidities.
Results: The adjusted odds ratio for dementia in those with previous insomnia was 1.34 (95% CI = 1.20-1.50).
Conclusion: There is an association between dementia and previous insomnia. It may be possible to incorporate insomnia into predictive tools for dementia
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