1,339 research outputs found
Longitudinal and Transverse Form Factors from C
Electron scattering form factors from C have been studied in the
framework of the particle-hole shell model. Higher configurations are taken
into account by allowing particle-hole excitations from the 1 and 1
shells core orbits up to the 1 shell. The inclusion of the higher
configurations modifies the form factors markedly and describes the
experimental data very well in all momentum transfer regions.Comment: 5 pages, 5 figures, 3 tables, late
The effect of core polarization on longitudinal form factors in B
Electron scattering Coulomb form factors for the single-particle quadrupole
transitions in -shell B nucleus have been studied. Core polarization
effects are included through a microscopic theory that includes excitations
from the core orbits up to higher orbits with 2 excitations. The
modified surface delta interaction (MSDI) is employed as a residual
interaction. The effect of core polarization is found essential in both the
transition strengths and momentum transfer dependence of form factors, and
gives a remarkably good agreement with the measured data with no adjustable
parameters.Comment: 4 pages, 5 figure
Full -shell study of even-even Ti isotopes
The level schemes and transition rates {\em B}({\em E}2;) of
eve-even Ti isotopes were studied by performing large-scale shell
model calculations with FPD6 and GXPF1 effective interactions. Excellent
agreement were obtained by comparing the first 2 level for all isotopes
with the recently available experimental data, but studying the transition
strengths {\em B}({\em E}2; 0) for all Ti isotopes using
constant proton-neutron effective charges prove the limitations of the present
large-scale calculations to reproduce the experiment in detail.Comment: 4 pages, 4 figure
Dipole and Quadrupole electroexcitations of the isovector T=1 particle-hole states in C-12
Electroexcitations of the dominantly T=1 particle-hole states of C-12 are
studied in the framework of the harmonic oscillator shell model. All possible
T=1 single-particle-hole states of all allowed angular momenta are considered
in a basis including single-particle states up to the 1f-2p shell. The
Hamiltonian is diagnoalized in this space in the presence of the modified
surface delta interaction. Correlation in the ground state wave functions by
mixing more than one configuration is considered and shows a major contribution
that leads to enhance the calculations of the form factors. A comparison with
the experiment shows that this model is able to fit the location of states and
a simple scaling of the results give a good fit to the experimental form
factors.Comment: 5 pages, 4 figures, 5 tables, Late
Synergistic effect of energy drinks and overweight/obesity on cardiac autonomic testing using the Valsalva maneuver in university students
BACKGROUND: Obesity and caffeine consumption may lead to autonomic disturbances that can result in a wide range of cardiovascular disorders.
OBJECTIVES: To determine autonomic disturbances produced by the synergistic effects of overweight or obesity (OW/OB) and energy drinks.
DESIGN: Cross-sectional, analytical.
SETTING: Physiology department at a university in Saudi Arabia.
SUBJECTS AND METHODS: University students, 18â22 years of age, of normal weight (NW) and OW/OB were recruited by convenience sampling. Autonomic testing by the Valsalva ratio (VR) along with systolic and diastolic blood pressure, pulse pressure, and mean arterial blood pressure were measured at baseline (0 minute) and 60 minutes after energy drink consumption.
MAIN OUTCOME MEASURE(S): Autonomic disturbance, hemodynamic changes.
RESULTS: In 50 (27 males and 23 females) subjects, 21 NW and 29 OW/OB, a significant decrease in VR was observed in OW/OB subjects and in NW and OW/OB females at 60 minutes after energy drink consumption. Values of systolic and diastolic blood pressure, pulse pressure and mean arterial blood pressure were also significantly higher in OW/OB and in females as compared to NW and males. BMI was negatively correlated with VR and diastolic blood pressure at 60 minutes.
CONCLUSION: Obesity and energy drinks alter autonomic functions. In some individuals, OW/OB may augment these effects.
LIMITATIONS: Due to time and resource restraints, only the acute effects of energy drinks were examined
Smoking, SARS-CoV-2 and COVID-19: a review of reviews considering implications for public health policy and practice
IntroductionThere has been significant speculation regarding the association between Severe Acute RespiratorySyndrome Coronavirus 2 (SARS-CoV-2) pathogen, coronavirus disease (COVID-19) and smoking.We provide an overview of the available literature regarding the association between smoking, risk ofSARS-CoV-2 infection, and risk of severe COVID-19 and poor clinical outcomes, with the aim ofinforming public health policy and practice in England.MethodsPublications were identified utilising a systematic search approach on PUBMED and Google Scholar.Publications presenting a systematic review or meta-analysis considering the association betweensmoking and SARS-COV-2 infection or COVID-19 outcomes were included.ResultsEight studies were identified. One considered the relationship between smoking and the probability ofSARS-CoV-2 infection, three considered the association between COVID-19 hospitalisation andsmoking history and six reviewed the association between smoking history and development ofsevere COVID-19. One study specifically investigated the risk of mortality. The studies consideringrisk of severe disease indicate that there is a significant association between COVID-19 and currentor ever smoking.ConclusionsThis is a rapidly evolving topic. Current analysis remains limited due to the quality of primary data,although early results indicate an association between smoking and COVID-19 severity. We highlyrecommend public health messaging to continue focusing on smoking cessation efforts
Structural and optical properties Investigation of ZnxCd1-xS thin films
CdZnXS1-X thin films with different composition have been deposited on glass substrate by by the spray pyrolysis method at RT using CdCl2 (0.1M),ZnCl2(0.1M)and H2NCSNH2(0.1M)solution and a substrate temperature of ( 400ñ20Ă°C). X-ray diffraction studies reveal that the films are polycrystalline in nature with hexagonal structure and preferential orientation along (002) . The grain size of the films is found to increase formĂ (37.397 to 46.902) nm with increasing Zinc concentration while the strain and the dislocation density of the films are found to decrease from (7.15 to 4.54) 10 4 rad and from (3.82 to 1.93) 10 14 lines.m-2 respectively . TheĂ transmittanceĂ spectrumsĂ ofĂ CdZnxS1-xĂ thinĂ filmsĂ reveal very pronounced interference effects for photon energies below the fundamental absorption edge by exhibiting interference pattern . The optical energy gap for CdZnxS1-x thin films increases and shifts towards the UV regionĂ as theĂ Zn concentration in the films increased .Ă
Outputs and Growth of Primary Care Databases in the United Kingdom: Bibliometric Analysis.
BACKGROUND: Electronic health database (EHD) data is increasingly used by researchers. The major United Kingdom EHDs are the 'Clinical Practice Research Datalink' (CPRD), 'The Health Improvement Network' (THIN) and 'QResearch'. Over time, outputs from these databases have increased, but have not been evaluated. OBJECTIVE: This study compares research outputs from CPRD, THIN and QResearch assessing growth and publication outputs over a 10-year period (2004-2013). CPRD was also reviewed separately over 20 years as a case study. METHODS: Â Publications from CPRD and QResearch were extracted using the Science Citation Index (SCI) of the Thomson Scientific Institute for Scientific Information (Web of Science). THIN data was obtained from University College London and validated in Web of Science. All databases were analysed for growth in publications, the speciality areas and the journals in which their data have been published. RESULTS: These databases collectively produced 1,296 publications over a ten-year period, with CPRD representing 63.6% (n=825 papers), THIN 30.4% (n=394) and QResearch 5.9% (n=77). Pharmacoepidemiology and General Medicine were the most common specialities featured. Over the 9-year period (2004-2013), publications for THIN and QResearch have slowly increased over time, whereas CPRD publications have increased substantially in last 4 years with almost 75% of CPRD publications published in the past 9 years. CONCLUSION: These databases are enhancing scientific research and are growing yearly, however display variability in their growth. They could become more powerful research tools if the National Health Service and general practitioners can provide accurate and comprehensive data for inclusion in these databases
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