9,503 research outputs found
Recommended from our members
Many Californians With Asthma Have Problems Understanding Their Doctor
Examines the prevalence and consequences of communication problems with doctors among adult asthma patients by education, income, insurance status, English proficiency, race/ethnicity, and nativity. Recommends customized education materials and programs
Influence of pairing correlations on the radius of neutron-rich nuclei
The influence of pairing correlations on the neutron root mean square (rms)
radius of nuclei is investigated in the framework of self-consistent Skyrme
Hartree-Fock-Bogoliubov calculations. The continuum is treated appropriately by
the Green's function techniques. As an example the nucleus Zr is
treated for a varying strength of pairing correlations. We find that, as the
pairing strength increases, the neutron rms radius first shrinks, reaches a
minimum and beyond this point it expands again. The shrinkage is due to the the
so-called `pairing anti-halo effect', i. e. due to the decreasing of the
asymptotic density distribution with increasing pairing. However, in some
cases, increasing pairing correlations can also lead to an expansion of the
nucleus due to a growing occupation of so-called `halo' orbits, i.e. weakly
bound states and resonances in the continuum with low- values. In this
case, the neutron radii are extended just by the influence of pairing
correlations, since these `halo' orbits cannot be occupied without pairing. The
term `anti-halo effect' is not justified in such cases. For a full
understanding of this complicated interplay self-consistent calculations are
necessary.Comment: 18 pages, 5 figure
Lions grazing on the dragon’s land: South African firms’ business strategies in the Chinese market: navigating institutions
This research project is one of the first studies to focus on South African foreign direct investment (FDI) in Mainland China. Specifically, the research aims to identify and specify the key institutional factors that have contributed to the effectiveness or otherwise of South African firms entering and operating within the Chinese market, as well as to investigate the characteristics and processes that have effectively shaped South African firms’ business strategies to negotiate the current Chinese institutional environment.
The research adopts an institutional perspective, fusing two separate disciplinary study frameworks, international business (IB) and international political economy (IPE), to draw out the key institutional factors that South African firms entering and operating within the Chinese market have encountered. The principal contributions of the thesis are conceptual and empirical: the latter presenting case studies of a cross-section of South African business actors who have sought to penetrate the Chinese market; the former centring of a model which emphasises the importance of both formal and informal business processes and practices in influencing business success and failure in context
TetraÂaquaÂ{1-[(1H-1,2,3-benzotriazol-1-yl)methÂyl]-1H-imidazole}ÂsulfatoÂmanganese(II) dihydrate
In the title complex, [Mn(SO4)(C10H9N5)(H2O)4]·2H2O, the Mn2+ cation is six-coordinated by one N atom from a 1-[(1H-1,2,3-benzotriazol-1-yl)methÂyl]-1H-imidazole ligand and five O atoms from one monodentate sulfate ligand and four water molÂecules in a distorted octaÂhedral geometry. In the crystal, adjacent molÂecules are linked through O—H⋯O and O—H⋯N hydrogen bonds into a three-dimensional network
Analysis and evaluation of the entropy indices of a static network structure
Although degree distribution entropy (DDE), SD structure entropy (SDSE), Wu structure entropy (WSE) and FB structure entropy (FBSE) are four static network structure entropy indices widely used to quantify the heterogeneity of a complex network, previous studies have paid little attention to their differing abilities to describe network structure. We calculate these four structure entropies for four benchmark networks and compare the results by measuring the ability of each index to characterize network heterogeneity. We find that SDSE and FBSE more accurately characterize network heterogeneity than WSE and DDE. We also find that existing benchmark networks fail to distinguish SDSE and FBSE because they cannot discriminate local and global network heterogeneity. We solve this problem by proposing an evolving caveman network that reveals the differences between structure entropy indices by comparing the sensitivities during the network evolutionary process. Mathematical analysis and computational simulation both indicate that FBSE describes the global topology variation in the evolutionary process of a caveman network, and that the other three structure entropy indices reflect only local network heterogeneity. Our study offers an expansive view of the structural complexity of networks and expands our understanding of complex network behavior.The authors would like to thank the financial support of the National Natural Science Foundation of China (71501153), Natural Science Foundation of Shaanxi Province of China (2016JQ6072), and the Foundation of China Scholarship Council (201506965039, 201606965057). (71501153 - National Natural Science Foundation of China; 2016JQ6072 - Natural Science Foundation of Shaanxi Province of China; 201506965039 - Foundation of China Scholarship Council; 201606965057 - Foundation of China Scholarship Council)Published versio
Recommended from our members
Environmental public health tracking of childhood asthma using California health interview survey, traffic, and outdoor air pollution data.
BackgroundDespite extensive evidence that air pollution affects childhood asthma, state-level and national-level tracking of asthma outcomes in relation to air pollution is limited.ObjectivesOur goals were to evaluate the feasibility of linking the 2001 California Health Interview Survey (CHIS), air monitoring, and traffic data; estimate associations between traffic density (TD) or outdoor air pollutant concentrations and childhood asthma morbidity; and evaluate the usefulness of such databases, linkages, and analyses to Environmental Public Health Tracking (EPHT).MethodsWe estimated TD within 500 feet of residential cross-streets of respondents and annual average pollutant concentrations based on monitoring station measurements. We used logistic regression to examine associations with reported asthma symptoms and emergency department (ED) visits/hospitalizations.ResultsAssignment of TD and air pollution exposures for cross-streets was successful for 82% of children with asthma in Los Angeles and San Diego, California, Counties. Children with asthma living in high ozone areas and areas with high concentrations of particulate matter < 10 microm in aerodynamic diameter experienced symptoms more frequently, and those living close to heavy traffic reported more ED visits/hospitalizations. The advantages of the CHIS for asthma EPHT include a large and representative sample, biennial data collection, and ascertainment of important socio-demographic and residential address information. Disadvantages are its cross-sectional design, reliance on parental reports of diagnoses and symptoms, and lack of information on some potential confounders.ConclusionsDespite limitations, the CHIS provides a useful framework for examining air pollution and childhood asthma morbidity in support of EPHT, especially because later surveys address some noted gaps. We plan to employ CHIS 2003 and 2005 data and novel exposure assessment methods to re-examine the questions raised here
The Extended Wronskian Determinant Approach and the Iterative Solutions of One-Dimensional Dirac Equation
An approximation method, namely, the Extended Wronskian Determinant Approach,
is suggested to study the one-dimensional Dirac equation. An integral equation
which can be solved by iterative procedure to find the wave functions is
established. We employ this approach to study the one-dimensional Dirac
equation with one-well potential, and give the energy levels and wave functions
up to the first order iterative approximation. For double-well potential, the
energy levels up to the first order approximation are given.Comment: 3 figures, 21 page
- …