6,127 research outputs found
Seroprevalence of Hepatitis E among Boston Area Travelers, 2009-2010
We determined the prevalence of IgG antibodies to hepatitis E virus (anti-HEV IgG) among travelers
attending Boston-area travel health clinics from 2009 to 2010. Pre-travel samples were available for 1,356 travelers,
with paired pre- and post-travel samples for 450 (33%). Eighty of 1,356 (6%) pre-travel samples were positive
for anti-HEV IgG. Compared with participants who had never lived in nor traveled to a highly endemic
country, the pre-travel prevalence odds ratio (POR) of anti-HEV IgG among participants born in or with a history
of previous travel to a highly endemic country was increased (POR = 4.8, 95% CI = 2.3–10.3 and POR = 2.6,
95% CI = 1.4–5.0, respectively). Among participants with previous travel to a highly endemic country, anti-HEV
IgG was associated with age > 40 years (POR = 3.7, 95% CI = 1.3–10.2) and travel history to ≥ 3 highly endemic
countries (POR = 2.7, 95% CI = 1.2–5.9). Two participants may have contracted HEV infection during their
2009–2010 trip
Innovative Double H Metamaterial Structure for Amelioration in Patch Antenna Parameters
A rectangular microstrip patch antenna along with a SSRR based “Double H” shaped metamaterial is proposed and analyzed at a height of 3.2mm from the ground plane. This work is mainly focused on increasing the potential parameters of microstrip patch antennas. The patch antenna along with the proposed metamaterial structure is designed to resonate at 1.84GHz. The impedance bandwidth of the patch antenna along with the proposed metamaterial structure is improved by 12.9MHz and return loss is reduced by 9.89dB. All the simulation work is done by using CST-MWS Software. Double-Negative properties (Negative Permeability and Permittivity) of the proposed metamaterial structure have also been verified using Nicolson-Ross-Weir method (NRW)
Co-evolution of RDF Datasets
Linking Data initiatives have fostered the publication of large number of RDF
datasets in the Linked Open Data (LOD) cloud, as well as the development of
query processing infrastructures to access these data in a federated fashion.
However, different experimental studies have shown that availability of LOD
datasets cannot be always ensured, being RDF data replication required for
envisioning reliable federated query frameworks. Albeit enhancing data
availability, RDF data replication requires synchronization and conflict
resolution when replicas and source datasets are allowed to change data over
time, i.e., co-evolution management needs to be provided to ensure consistency.
In this paper, we tackle the problem of RDF data co-evolution and devise an
approach for conflict resolution during co-evolution of RDF datasets. Our
proposed approach is property-oriented and allows for exploiting semantics
about RDF properties during co-evolution management. The quality of our
approach is empirically evaluated in different scenarios on the DBpedia-live
dataset. Experimental results suggest that proposed proposed techniques have a
positive impact on the quality of data in source datasets and replicas.Comment: 18 pages, 4 figures, Accepted in ICWE, 201
Compact Modeling for a Double Gate MOSFET
MOSFETs (metal-oxide-silicon field-effect transistors) are an integral part of modern electronics. Improved designs are currently under investigation, and one that is promising is the double gate MOSFET.
Understanding device characteristics is critical for the design of MOSFETs as part of design tools for integrated circuits such as SPICE. Current methods involve the numerical solution of PDEs governing electron transport. Numerical solutions are accurate, but do not provide an appropriate way to optimize the design of the device, nor are they suitable for use in chip simulation software such as SPICE. As chips contain more and more transistors, this problem will get more and more acute.
There is hence a need for analytic solutions of the equations governing the performance of MOSFETs, even if these are approximate. Almost all solutions in the literature treat the long-channel case (thin devices) for which the PDEs reduce to ODEs. The goal of this problem is to produce analytical solutions based on the underlying PDEs that are rapid to compute (e.g. require solving only a small number of algebraic equations rather than systems of PDEs).
Guided by asymptotic analysis, a fast numerical procedure has been developed to obtain approximate solutions of the governing PDEs governing MOSFET properties, namely electron density, Fermi potential and electrostatic potential. The approach depends on the channel’s being long enough, and appears accurate in this limit
Shape Complexity from Image Similarity
We present an approach to automatically compute the complexity of a given 3D shape. Previous approaches have made use of geometric and/or topological properties of the 3D shape to compute complexity. Our approach is based on shape appearance and estimates the complexity of a given 3D shape according to how 2D views of the shape diverge from each other. We use similarity among views of the 3D shape as the basis for our complexity computation. Hence our approach uses claims from psychology that humans mentally represent 3D shapes as organizations of 2D views and, therefore, mimics how humans gauge shape complexity. Experimental results show that our approach produces results that are more in agreement with the human notion of shape complexity than those obtained using previous approaches
Are our people health conscious? results of a patients survey in Karachi, Pakistan
BACKGROUND: Life style is known to influence health and may be responsible for certain diseases. There is a need to document the life style on health among the Pakistani population. METHODS: The study was conducted on patients visiting the Family Practice Center, the Aga Khan University, Karachi. A questionnaire was used to collect information on the demographic profile, and the life style on health. The ethical requirements for conducting the study were met. RESULTS: 393 patients were surveyed. The majority were young married men, in either private or government service. Preference for consumption of fats/oils, sweets, spicy foods, salt, fruits/vegetables, tea, coffee, cola drinks and alcohol was found among 103 (26%), 84 (22%), 86 (22%), 110 (28%), 239 (61%), 319 (81%), 117 (30%), 253 (64%) and 13 (03%) respondents respectively. Hand washing after defecation, before eating food and after work was seen among 341 (87%), 296 (75%) and 256 (65%) respondents respectively. Brushing of teeth after eating food, before breakfast and bedtime was seen in 56 (14%), 346 (88%) and 176 (45%) respondents respectively. Preventive dental check-up was practiced by 102 (26%) of the respondents. Sleep of less than 6 hours per day among 74 (19%), water consumption of less than 1 liter daily among 84 (21%) and fish consumption on once a week basis among 173 (44%) respondents was found. Tobacco and betel nuts use was found among 69 (17%) and 79 (20%) respondents. CONCLUSIONS: We have documented a clear need to raise public awareness on the issue of life style on health. There is a need and we strongly recommend debate and further research, along with interventional strategies in line with the available evidence on healthy life style
From Local Velocities to Microwave Background
The mass density field as extracted from peculiar velocities in our
cosmological neighborhood is mapped back in time to the CMB in two ways. First,
the density power spectrum () is translated into a temperature angular
power spectrum of sub-degree resolution () and compared to observations.
Second, the local density field is translated into a temperature map in a patch
on the last-scattering surface of a distant observer. A likelihood analysis of
the Mark III peculiar velocity data have constrained the range of parameters
for within the family of COBE-normalized CDM models (Zaroubi et al 1996),
favoring a slight tilt in the initial spectrum, . The corresponding range
of 's is plotted against current observations, indicating that the CMB
data can tighten the constraints further: only models with ``small'' tilt
() and ``high'' baryonic content () could survive
the two data sets simultaneously. The local mass density field that has been
recovered from the velocities via a Wiener method is convolved with a Boltzmann
calculation to recover resolution temperature maps as viewed from
different directions. The extent of the CMB patch and the amplitude of
fluctuations depend on the choice of cosmological parameters, e.g., the local
100\hmpc sphere corresponds to to at the CMB for between
1 and 0 respectively. The phases of the temperature map are correlated with
those of the density field, contrary to the contribution of the Sachs-Wolfe
effect alone. This correlation suggests the possibility of an inverse
reconstruction of the underlying density field from CMB data with interesting
theoretical implications.Comment: 16 pages, 6 figures. Submitted to Ap.
Yield and Production Costs for Three Potential Dedicated Energy Crops in Mississippi and Oklahoma Environments
The objective of this paper is to determine production costs of switchgrass, eastern gammagrass, and giant miscanthus using Mississippi and Oklahoma data. Production costs were computed using a standard enterprise budgeting approach by species and method of harvest. Results indicate cost difference across species and method of harvest.Yield and Cost, biomass species, Crop Production/Industries, Resource /Energy Economics and Policy,
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