5,004 research outputs found
Black hole solutions in f(R) gravity coupled with non-linear Yang-Mills field
It is shown that in the static, spherically symmetric spacetime the problem
of metric f(R) gravity coupled with non-linear Yang-Mills (YM) field
constructed from the Wu-Yang ansatz as source, can be solved in all dimensions.
By non-linearity it is meant that the YM Lagrangian depends arbitrarily on its
invariant. A particular form is considered to be in the power-law form with
limit of the standard YM theory. The formalism admits black hole solutions with
single or double horizons in which f(R) can be obtained, in general
numerically. In 6-dimensional case we obtain an exact solution given by
f(R)=\surdR gravity that couples with the YM field in a consistent manner.Comment: 12 pages, 8 figures, revised version with major changes including
expanded references. Dedicated to the memory of Yavuz Nutku (1943-2010
Robust Cardiac Motion Estimation using Ultrafast Ultrasound Data: A Low-Rank-Topology-Preserving Approach
Cardiac motion estimation is an important diagnostic tool to detect heart
diseases and it has been explored with modalities such as MRI and conventional
ultrasound (US) sequences. US cardiac motion estimation still presents
challenges because of the complex motion patterns and the presence of noise. In
this work, we propose a novel approach to estimate the cardiac motion using
ultrafast ultrasound data. -- Our solution is based on a variational
formulation characterized by the L2-regularized class. The displacement is
represented by a lattice of b-splines and we ensure robustness by applying a
maximum likelihood type estimator. While this is an important part of our
solution, the main highlight of this paper is to combine a low-rank data
representation with topology preservation. Low-rank data representation
(achieved by finding the k-dominant singular values of a Casorati Matrix
arranged from the data sequence) speeds up the global solution and achieves
noise reduction. On the other hand, topology preservation (achieved by
monitoring the Jacobian determinant) allows to radically rule out distortions
while carefully controlling the size of allowed expansions and contractions.
Our variational approach is carried out on a realistic dataset as well as on a
simulated one. We demonstrate how our proposed variational solution deals with
complex deformations through careful numerical experiments. While maintaining
the accuracy of the solution, the low-rank preprocessing is shown to speed up
the convergence of the variational problem. Beyond cardiac motion estimation,
our approach is promising for the analysis of other organs that experience
motion.Comment: 15 pages, 10 figures, Physics in Medicine and Biology, 201
Zoonotic disease management and infection control practices among veterinarians in the United Arab Emirates
This study was conducted to assess zoonotic disease management and infection control practices (ICPs) among veterinarians in the United Arab Emirates (UAE). A questionnaire was developed in SurveyMonkey, an online tool, and was distributed by email during February–May 2020 to 470 veterinarians practicing across the UAE. A total of 110 individuals completed the survey, giving a response rate of 23.4% (110/470). Results indicate that reported hand hygiene, sharps management, barrier or isolation practices, and personal choices for personal protective equipment (PPE) in common practice scenarios varied among practitioners. The majority (>75%) of veterinarians in all practice types reported always washing their hands before eating, drinking, or smoking at work. The survey revealed that 19% and 10% of large and small animal veterinarians indicated they sterilized and reused disposable needles. Veterinarians among all practices indicated high rates (75% to 80%) of recapping needles before disposal. When handling an animal suspected of having a zoonotic disease, most (90%) of small animal veterinarians reported always using practices such as isolating the animal and removing outwear before contact with other animals. However, only half (55%) of the large animal respondents reported always isolating the animal or sterilizing all equipment used on the animal of concern. Fewer than half of the large animal (35%) and mixed practice (44%) veterinarians indicated they would always be limiting human contact with the animal of concern. All of the small animal respondents reported full compliance with PPE while performing surgery and necropsy. Among large animal veterinarians, 44% reported not using respiratory or eye protection when aiding with parturition or handling conception products. Failure to use appropriate PPE when handling blood samples was the second most common noncompliant practice among large animal (39%) veterinarians and mixed practice (41%) respondents. Our study indicates a need for continuous education regarding ICPs in the veterinary community in the UAE. Better awareness of the risk of zoonotic disease exposure and options for managing this risk and liability issues could drive the adoption of infection control practices
Risk factors associated with brucella seropositivity in sheep and goats in Duhok Province, Iraq
Sera from 432 small ruminants (335 sheep and 97 goats) from 72 farms in Duhok Province, northern Iraq, were collected to investigate risk factors associated with brucellosis seropositivity. Serum samples were tested using the Rose Bengal test (RBT) and an indirect enzyme-linked immunosorbent assay (iELISA). Using parallel interpretation, RBT and iELISA results showed that 31.7% (95% confidence interval (CI): 26.1, 36.3) of sheep and 34.0% (95% CI: 24.7, 44.3) of goats had antibodies against Brucella in the study area. A random-effects multivariable logistic regression model indicated that a higher chance of being seropositive (odds ratio (OR) = 1.7; 95% 1.4; 2.2) was associated with an increase in the age of animals. The odds of Brucella seropositivity in flocks where sheep and goats grazed together was 2.0 times higher (95% CI: 1.08; 3.9) compared to flocks where sheep and goats grazed separately. The odds of Brucella seropositivity in small ruminants was 2.2 higher (95% CI: 1.2; 4.3) for animals originating from farms with a history of goat abortion in the preceding 12 months. In contrast, for every 1000 Iraqi Dinars (~0.85 US Dollar) spent by the farmers on control of Brucella in their flocks, the odds of Brucella seropositivity decreased significantly (OR = 0.9, p-value = 0.021). The final model also indicated significant differences in Brucella seropositivity between the different districts of Duhok Province. This study provides a contribution to the epidemiology of brucellosis in small ruminants in northern Iraq
How to achieve Financial Gains with Corporate Social Responsibility in businesses
This research paper presents a conceptual framework for companies to manage their financial gains or profitability with the help of Corporate Social Responsibility initiatives and attempts. A case of Sharp electronics and Samsung will also be discussed that how these companies gain profits through implementing CSR in companies. And we will also do a graphical analysis of Asian countries involve in CSR activities. The results of the present study showed that an organization can increase its output by effectively using corporate social responsibility activities. Key words: Corporate Social Responsibility, Financial gains, Conceptual framewor
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