1,883 research outputs found
Mechanical properties of polycrystalline graphene based on a realistic atomistic model
Graphene can at present be grown at large quantities only by the chemical
vapor deposition method, which produces polycrystalline samples. Here, we
describe a method for constructing realistic polycrystalline graphene samples
for atomistic simulations, and apply it for studying their mechanical
properties. We show that cracks initiate at points where grain boundaries meet
and then propagate through grains predominantly in zigzag or armchair
directions, in agreement with recent experimental work. Contrary to earlier
theoretical predictions, we observe normally distributed intrinsic strength (~
50% of that of the mono-crystalline graphene) and failure strain which do not
depend on the misorientation angles between the grains. Extrapolating for grain
sizes above 15 nm results in a failure strain of ~ 0.09 and a Young's modulus
of ~ 600 GPa. The decreased strength can be adequately explained with a
conventional continuum model when the grain boundary meeting points are
identified as Griffith cracks.Comment: Accepted for Physical Review B; 5 pages, 4 figure
Ultracold polarized Fermi gas at intermediate temperatures
We consider non-zero temperature properties of the polarized two-component
Fermi gas. We point out that stable polarized paired states which are more
stable than their phase separated counterparts with unpolarized superfluid
region can exist below the critical temperature. We also solve the system
behavior in a trap using the local density approximation and find gradually
increasing polarization in the center of the system as the temperature is
increased. However, in the strongly interacting region the central polarization
increases most rapidly close to the mean-field critical temperature, which is
known to be substantially higher than the critical temperature for
superfluidity. This indicates that most of the phase separation occurs in the
fluctuation region prior to superfluidity and that the polarization in the
actual superfluid is modest.Comment: Final published versio
અમદાવાદના પત્રકારો : સામાજિક અન્વેષણના સંદર્ભમાં
Not availabl
A Qualitative Analysis of Homeless Women with Children in Transitional Housing: What Are Their Needs?
In 2004, the National Law Center on Homelessness and Poverty indicated that approximately 3.5 million people experienced homelessness. The literature indicates that families, specifically female-headed ones, are the fastest growing segment of the homeless population. The development of transitional housing has shown promise by seeking to move these homeless families towards independent living. A qualitative study based in grounded theory was utilized to explore the experiences of 10 female homeless participants at two regional transitional living facilities. Consistent themes that emerged included dissolution of relationships and a lack of personal supports as being the primary pathways that lead to homelessness. Concrete goals of women in transition focused on establishing housing and steady vocation. In an attempt to identify potential constructive programming congruent with the needs of homeless mothers, results overwhelmingly indicated that this population would benefit from problem-solving training, as well as additional networking opportunities. Application of the recovery model to the phenomenon of homelessness is also presented
Challenges and implications of routine depression screening for depression in chronic disease and multimorbidity: a cross sectional study
<b>Background</b> Depression screening in chronic disease is advocated but its impact on routine practice is uncertain. We examine the effects of a programme of incentivised depression screening in chronic disease within a UK primary care setting.<p></p>
<b>Methods and Findings</b> Cross sectional analysis of anonymised, routinely collected data (for 2008-9) from family practices in Scotland serving a population of circa 1.8 million. Patients registered in primary care with at least one of three chronic diseases, coronary heart disease, diabetes and stroke, underwent incentivised depression screening using the Hospital Anxiety and Depression Score (HADS). <p></p>
125143 patients were identified with at least one chronic disease. 10670 (8.5%) were under treatment for depression and exempt from screening. Of the remaining, HADS were recorded for 35537 (31.1%) patients. 7080 (19.9% of screened) had raised HADS (≥8); the majority had indications of mild depression with a HADS between 8 and 10. Over 6 months, 572 (8%) of those with a raised HADS (≥8) were initiated on antidepressants, while 696 (2.4%) patients with a normal HADS (<8) were also initiated on antidepressants (relative risk of antidepressant initiation with raised HADS 3.3 (CI 2.97-3.67), p value <0.0001). Of those with multimorbidity who were screened, 24.3% had a raised HADS (≥8). A raised HADS was more likely in females, socioeconomically deprived, multimorbid or younger (18-44) individuals. Females and 45-64 years old were more likely to receive antidepressants.<p></p>
<b>Limitations</b> – retrospective study of routinely collected data.<p></p>
<b>Conclusions </b> Despite incentivisation, only minority of patients underwent depression screening, suggesting that systematic depression screening in chronic disease can be difficult to achieve in routine practice. Targeting those at greatest risk such as the multimorbid or using simpler screening methods may be more effective. Raised HADS was associated with a higher number of new antidepressant prescriptions which has significant resource implications. The clinical benefits of such screening remain uncertain and merit investigation
A case of telescoping of bowel during sailing
Intussusceptions as an entity is more common in children than adults in whom it is almost always secondary to some associated pathology. Moreover, the presentation is subacute or chronic in nature and all classical features of intussusceptions are rarely present together that makes the diagnosis more challenging. Here we presented a case of ileo-ileal intussusception in an adult male. Obligation of early diagnosis, initial management is unique in such cases. It also focuses on importance of availability of the imaging facilities in management of acute abdomen so as to assist in timely diagnosis as well as the definitive management of intussusceptions.
Loss of correlation between HIV viral load and CD4+ T-cell counts in HIV/HTLV-1 co-infection in treatment naive Mozambican patients
Seven hundred and four HIV-1/2-positive, antiretroviral therapy (ART) naïve patients were screened for HTLV-1 infection. Antibodies to HTLV-1 were found in 32/704 (4.5%) of the patients. Each co-infected individual was matched with two HIV mono-infected patients according to World Health Organization clinical stage, age +/-5 years and gender. Key clinical and laboratory characteristics were compared between the two groups. Mono-infected and co-infected patients displayed similar clinical characteristics. However, co-infected patients had higher absolute CD4+ T-cell counts (P = 0.001), higher percentage CD4+ T-cell counts (P < 0.001) and higher CD4/CD8 ratios (P < 0.001). Although HIV plasma RNA viral loads were inversely correlated with CD4+ T-cell-counts in mono-infected patients (P < 0.0001), a correlation was not found in co-infected individuals (P = 0.11). Patients with untreated HIV and HTLV-1 co-infection show a dissociation between immunological and HIV virological markers. Current recommendations for initiating ART and chemoprophylaxis against opportunistic infections in resource-poor settings rely on more readily available CD4+ T-cell counts without viral load parameters. These guidelines are not appropriate for co-infected individuals in whom high CD4+ T-cell counts persist despite high HIV viral load states. Thus, for co-infected patients, even in resource-poor settings, HIV viral loads are likely to contribute information crucial for the appropriate timing of ART introduction
Harmonic Mean Cordial labeling of some graphs
All the graphs considered in this article are simple and undirected. Let G = (V(G), E(G)) be a simple undirected Graph. A function f : V (G) → {1, 2} is called Harmonic Mean Cordial if the induced function f*: E(G) → {1, 2} defined by f* (uv) = [2f(u)f(v)/f(u)+f(v)] satisfies the condition |vf (i) − vf (j)| ≤ 1 and |ef (i) − ef (j)| ≤ 1 for any i, j ∈ {1, 2}, where vf (x) and ef (x) denotes the number of vertices and number of edges with label x respectively and bxc denotes the greatest integer less than or equals to x. A Graph G is called Harmonic Mean Cordial graph if it admits Harmonic Mean Cordial labeling. In this article, we have provided some graphs which are not Harmonic Mean Cordial and also we have provided some graphs which are Harmonic Mean Cordial.Publisher's Versio
Higher-order mesoscopic fluctuations in quantum wires: Conductance and current cumulants
We study conductance cumulants and current cumulants
related to heat and electrical transport in coherent mesoscopic quantum wires
near the diffusive regime. We consider the asymptotic behavior in the limit
where the number of channels and the length of the wire in the units of the
mean free path are large but the bare conductance is fixed. A recursion
equation unifying the descriptions of the standard and Bogoliubov--de Gennes
(BdG) symmetry classes is presented. We give values and come up with a novel
scaling form for the higher-order conductance cumulants. In the BdG wires, in
the presence of time-reversal symmetry, for the cumulants higher than the
second it is found that there may be only contributions which depend
nonanalytically on the wire length. This indicates that diagrammatic or
semiclassical pictures do not adequately describe higher-order spectral
correlations. Moreover, we obtain the weak-localization corrections to
with .Comment: 7 page
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