536 research outputs found
Microclimatological, Pedological, and Geomorphological Studies in the Western Tasersiaq Area, Greenland During Summer 1964
Final Report - 30 April 1964 -29 July 1965During the summer 1964, personnel of The Ohio State University Institute of Polar Studies conducted a field program in the Sukkertoppen Ice Cap area of southwest Greenland. The program included studies of soil and mass wasting in the Tasersiaq area immediately east of the ice cap, and studies of the microclimatology across the eastern edge of the ice cap. The results of this research program are contained in four parts. Part I, by Adolph Kryger, discusses the microclimatological (excluding radiation) results of observations taken at four stations, one at the base of the slope below the eastern edge of the Sukkertoppen Ice Cap, two intermediate ones on the slope, and one at the edge of the glacier. Part II, by Fritz Loewe, discusses the radiation observations. Both have related their observations to those at other permanent stations along the western Greenland coast. Part III, by K. R. Everett, presents the results of studies of mass-wasting and patterned ground phenomena. Part IV, by N. Holowaychuk and K. R. Everett, contains most of the results of the pedological studies. The report herein includes the discussion of soil morphology,chemistry, and classification.U.S. Army Natick Laboratories, Contract No. DA-19-129-AMC-301(N
Exploration of Resonant Continuum and Giant Resonance in the Relativistic Approach
Single-particle resonant-states in the continuum are determined by solving
scattering states of the Dirac equation with proper asymptotic conditions in
the relativistic mean field theory (RMF). The regular and irregular solutions
of the Dirac equation at a large radius where the nuclear potentials vanish are
relativistic Coulomb wave functions, which are calculated numerically.
Energies, widths and wave functions of single-particle resonance states in the
continuum for ^{120}Sn are studied in the RMF with the parameter set of NL3.
The isoscalar giant octupole resonance of ^{120}Sn is investigated in a fully
consistent relativistic random phase approximation. Comparing the results with
including full continuum states and only those single-particle resonances we
find that the contributions from those resonant-states dominate in the nuclear
giant resonant processes.Comment: 16 pages, 2 figure
Particle-unstable nuclei in the Hartree-Fock theory
Ground state energies and decay widths of particle unstable nuclei are
calculated within the Hartree-Fock approximation by performing a complex
scaling of the many-body Hamiltonian. Through this transformation, the wave
functions of the resonant states become square integrable. The method is
implemented with Skyrme effective interactions. Several Skyrme parametrizations
are tested on four unstable nuclei: 10He, 12O, 26O and 28O.Comment: 5 pages, LaTeX, submitted to Phys. Rev. Let
Three-body Faddeev Calculation for 11Li with Separable Potentials
The halo nucleus Li is treated as a three-body system consisting of an
inert core of Li plus two valence neutrons. The Faddeev equations are
solved using separable potentials to describe the two-body interactions,
corresponding in the n-Li subsystem to a p resonance plus a
virtual s-wave state. The experimental Li energy is taken as input and
the Li transverse momentum distribution in Li is studied.Comment: 6 pages, RevTeX, 1 figur
Breakup Reactions of 11Li within a Three-Body Model
We use a three-body model to investigate breakup reactions of 11Li (n+n+9Li)
on a light target. The interaction parameters are constrained by known
properties of the two-body subsystems, the 11Li binding energy and
fragmentation data. The remaining degrees of freedom are discussed. The
projectile-target interactions are described by phenomenological optical
potentials. The model predicts dependence on beam energy and target,
differences between longitudinal and transverse momentum distributions and
provides absolute values for all computed differential cross sections. We give
an almost complete series of observables and compare with corresponding
measurements. Remarkably good agreement is obtained. The relative neutron-9Li
p-wave content is about 40%. A p-resonance, consistent with measurements at
about 0.5 MeV of width about 0.4 MeV, seems to be necessary. The widths of the
momentum distributions are insensitive to target and beam energy with a
tendency to increase towards lower energies. The transverse momentum
distributions are broader than the longitudinal due to the diffraction process.
The absolute values of the cross sections follow the neutron-target cross
sections and increase strongly for beam energies decreasing below 100 MeV/u.Comment: 19 pages, 14 figures, RevTeX, psfig.st
Comparison of insulin degludec and glargine U100 in patients with type 1 diabetes prone to severe nocturnal hypoglycaemia
Fabrication of super-hydrophobic nickel film on copper substrate with improved corrosion inhibition by electrodeposition process
Inspired by the famous “lotus effect”, we have fabricated the super-hydrophobic surfaces with nickel film on copper substrates using a one-step electrodeposition method. By adjusting processing time, water contact angle of as-prepared surfaces can reach as high as 160.3 ± 1.5° with small rolling angle of 3.0 ± 0.5°, showing excellent super-hydrophobicity. After the deposition of nickel coating, the pristine copper surfaces became much rough with packed cauliflower-/thorn-like clusters. This unique surface texture contributed to trapping large amount of air and forming the air cushion underneath the water droplet, which can prevent the liquids contacting the copper substrate. The examination of surface chemical compositions implied that the deposited super-hydrophobic coating consisted of nickel crystals and nickel myristate. In this research, the formation mechanism of the electrodeposited super-hydrophobicity was extensively explained based on the analyses of surface texture and surface chemistry. Moreover, the corrosion resistance of the as-fabricated super-hydrophobic surface was estimated by the potentiodynamic polarization tests as well as the electrochemical impedance spectroscopy (EIS) measurements. The results demonstrate that the super-hydrophobic nickel coating showed excellent corrosion inhibition in simulated seawater solution. The existence of the super-hydrophobic coating could be regarded as a barrier and thus provide a perfect air-liquid interface that inhibits the penetration of the corrosive ions. This facile and effective method of electrodeposition process offers a promising approach for mass production of super-hydrophobic surfaces on various metals
Spatial effects, sampling errors, and task specialization in the honey bee
Task allocation patterns should depend on the spatial distribution of work within the nest, variation in task demand, and the movement patterns of workers, however, relatively little research has focused on these topics. This study uses a spatially explicit agent based model to determine whether such factors alone can generate biases in task performance at the individual level in the honey bees, Apis mellifera. Specialization (bias in task performance) is shown to result from strong sampling error due to localized task demand, relatively slow moving workers relative to nest size, and strong spatial variation in task demand. To date, specialization has been primarily interpreted with the response threshold concept, which is focused on intrinsic (typically genotypic) differences between workers. Response threshold variation and sampling error due to spatial effects are not mutually exclusive, however, and this study suggests that both contribute to patterns of task bias at the individual level. While spatial effects are strong enough to explain some documented cases of specialization; they are relatively short term and not explanatory for long term cases of specialization. In general, this study suggests that the spatial layout of tasks and fluctuations in their demand must be explicitly controlled for in studies focused on identifying genotypic specialists
Protocol for a national, mixed-methods knowledge, attitudes and practices survey on non-communicable diseases
Background
Mongolia is undergoing rapid epidemiological transition with increasing urbanisation and economic development. The lifestyle and health of Mongolians are changing as a result, shown by the 2005 and 2009 STEPS surveys (World Health Organization's STEPwise Approach to Chronic Disease Risk Factor Surveillance) that described a growing burden of Non-Communicable Diseases and injuries (NCDs).
This study aimed to assess, describe and explore the knowledge, attitudes and practices of the Mongolian adult population around NCDs in order to better understand the drivers and therefore develop more appropriate solutions to this growing disease burden. In addition, it aimed to provide data for the evaluation of current public health programs and to assist in building effective, evidence-based health policy.
Methods/design
This national survey consisted of both quantitative and qualitative methods. A quantitative household-based questionnaire was conducted using a nationally representative sample of 3854 rural and urban households. Participants were selected using a multi-stage cluster sampling technique in 42 regions across Mongolia, including rural and urban sites. Permanent residents of sampled households were eligible for recruitment, if aged between 15-64 years. This quantitative arm was then complemented and triangulated with a qualitative component: twelve focus group discussions focusing on diet, exercise and alcohol consumption. Discussions took place in six sites across the country, facilitated by local, trained health workers. These six sites were chosen to reflect major Mongolian cultural and social groups.
Discussion
KAP surveys are well represented in the literature, but studies that aim to explore the knowledge, attitudes and practices of a population around NCDs remain scarce. This is despite the growing number of national epidemiological surveys, such as STEPS, which aim to quantify the burden of these diseases but do not explore the level of population-based awareness, understanding, risk-perception and possible motivation for change. Therefore this paper will contribute to building a knowledge base of NCD KAP survey methodology for future use in epidemiology and research worldwide
A 2-week, polysomnographic, safety study of sodium oxybate in obstructive sleep apnea syndrome
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