896 research outputs found
Study of 5.8 GHz Band-Stop Frequency Selective Surface (FSS)
This paper presents the study of 5.8 GHz frequency selective surface (FSS) acts as a band stop to eliminate unwanted radiation signal at 5.8GHz. The FSS was designed using computer simulation technology (CST) Microwave Studio software. The paper shows the comparison of square loop, octagon loop and hexagon loop of Band stop FSS (BSFSS) performance at 5.8 GHz. Besides, the BSFSS design using four different type of dielectric substrate such as FR-4, TLY-5, Roger RT5870 and Roger RT5880 were compared. The results obviously show that the Rogers RY5880 has the attenuation -44.72 dB. The fabricated FSS were measured by using free space technique with two horn antennas connected to performance network analyzer (PNA). The measured and simulated results were compared. The results show that the square loop FSS structure have the better attenuation -26.76 dB (simulated) and -38.34 dB (measured) at 5.8 GHz
Canine vector borne diseases of zoonotic concern in three dog shelters in Peninsular Malaysia: the importance of preventive measures
This study investigated canine vector borne diseases (CVBDs) of zoonotic significance in three major shelters in Peninsular Malaysia in order to highlight the importance of shelter management in diseases prevention. Since crowded housing has the potential to bring vectors and infected dogs into close proximity, the prevalence of CVBDs infection is always higher in sheltered dogs in comparison to pet dogs. Serum was collected from 90 adult dogs (30 from each shelter) from three shelters in different regions of Peninsular Malaysia (Shelter A, B and C). The prevalence of Dirofilaria immitis, Ehrlichia canis, E. ewingii, Anaplasma phagocytophilum, A. platys and Borrelia burgdorferi in dogs residing in three shelters with different management protocols was investigated by using rapid clinical test kits, SNAP® 4Dx® Plus (IDEXX Laboratories, Westbrook, ME). The most common pathogen detected was Ehrlichia spp. (55.6%, 50 out of 90 dogs), followed by Anaplasma spp. (16.7%; 15 out of 90 dogs). Dirofilaria immitis could only be detected in one of the shelters (10.0%; nine out of 90 dogs). No evidence of B. burgdorferi was detected in all three shelters. Forty one out of 90 dogs (45.6%) were infected with at least one pathogen meanwhile 14 out of 90 dogs (15.6%) were infected with more than one pathogen. It is of crucial importance to practice preventive measures during the admission of the new animals into the facilities. Occasional treatment of the dogs (as practiced in Shelter B) was not effective when compared to scheduled preventive measures. Future studies should emphasize the isolation and additional molecular characterization of vector borne pathogens in Peninsular Malaysia. In addition, studies that define the tick species that infest dogs in this region would help to elucidate their role as vectors for disease transmission
Chytrid Fungus (Batrachochytrium dendrobatidis) Undetected in the Two Orders of Seychelles Amphibians
Reports the first disease screening for chytrid Fungus (Batrachochytrium dendrobatidis) in amphibians across the Seychelles Archipelag
Chronic migraine, comorbidity and socioeconomic deprivation: cross-sectional analysis of a large nationally representative primary care database
Background: Chronic migraine is common but there is limited knowledge on associated comorbidities. Objectives:
To examine mental and physical comorbidities in chronic migraine and the influence of socioeconomic
status in a large, nationally representative dataset. Design: Analysis of cross-sectional primary healthcare data
from 1,468,404 adults in Scotland. Chronic migraine, 31 other physical conditions, and seven mental health conditions
we examined. Prevalence rates were standardized by age groups, sex, and socioeconomic deprivation, and
adjusted odds ratio (aOR) and 95% confidence intervals (CI) calculated for those with chronic migraine compared
with those without. Results: Chronic migraine patients had more conditions, with the biggest difference
found for five or more conditions (chronic migraine 11.7% vs. controls 4.9%; aOR 3.00; 95% CI 2.78–3.22).
Twenty-five of the 31 physical conditions were significantly more prevalent in the chronic migraine group. The
biggest difference was for chronic pain (aOR 4.33; 95% CI 4.12–4.55). For mental health conditions, the biggest
differences were for anxiety (aOR 2.95; 95% CI 2.76–31.5) and depression (aOR 2.94; 95% CI 2.81–3.08).
Increasing deprivation was associated with more severe and complex comorbidity (five or more conditions), and
with more combined mental and physical comorbidity in the chronic migraine group. Conclusions: In a large
nationally representative sample in primary care, comorbidity was most common in those with chronic migraine
compared with standardized controls, and this was exacerbated by living in areas of higher deprivation
Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space
Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202
Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space
Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202
(13) C magnetic resonance spectroscopy measurements with hyperpolarized [1-(13) C] pyruvate can be used to detect the expression of transgenic pyruvate decarboxylase activity in vivo.
PURPOSE: Dissolution dynamic nuclear polarization can increase the sensitivity of the (13) C magnetic resonance spectroscopy experiment by at least four orders of magnitude and offers a novel approach to the development of MRI gene reporters based on enzymes that metabolize (13) C-labeled tracers. We describe here a gene reporter based on the enzyme pyruvate decarboxylase (EC 4.1.1.1), which catalyzes the decarboxylation of pyruvate to produce acetaldehyde and carbon dioxide. METHODS: Pyruvate decarboxylase from Zymomonas mobilis (zmPDC) and a mutant that lacked enzyme activity were expressed using an inducible promoter in human embryonic kidney (HEK293T) cells. Enzyme activity was measured in the cells and in xenografts derived from the cells using (13) C MRS measurements of the conversion of hyperpolarized [1-(13) C] pyruvate to H(13) CO3-. RESULTS: Induction of zmPDC expression in the cells and in the xenografts derived from them resulted in an approximately two-fold increase in the H(13) CO3-/[1-(13) C] pyruvate signal ratio following intravenous injection of hyperpolarized [1-(13) C] pyruvate. CONCLUSION: We have demonstrated the feasibility of using zmPDC as an in vivo reporter gene for use with hyperpolarized (13) C MRS. Magn Reson Med 76:391-401, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.PD was in receipt of a studentship funded by CRUK and S.-S.T. a Yousef Jameel studentship. TBR was in receipt of an Intra-European Marie Curie (FP7-PEOPLE- 2009-IEF, Imaging Lymphoma) and Long-term EMBO (EMBO-ALT-1145-2009) fellowships and E.M.S. and I.M.R were recipients of fellowships from the European Union Seventh Framework Programme (FP7/2007-2013) under the Marie Curie Initial Training Network METAFLUX (project number 264780). E.M.S. also acknowledges the educational support of Programme for Advanced Medical Education from Calouste Gulbenkian Foundation, Champalimaud Foundation, Ministerio de Saude and Fundacao para a Ciencia e Tecnologia, Portugal. The work was supported by a CRUK Programme Grant (17242) to KMB. The polarizer and related materials were provided by GE-Healthcare.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/mrm.2587
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
A Multimodal Problem for Competitive Coevolution
Coevolutionary algorithms are a special kind of evolutionary algorithm with advantages in solving certain specific kinds of problems. In particular, competitive coevolutionary algorithms can be used to study problems in which two sides compete against each other and must choose a suitable strategy. Often these problems are multimodal - there is more than one strong strategy for each side. In this paper, we introduce a scalable multimodal test problem for competitive coevolution, and use it to investigate the effectiveness of some common coevolutionary algorithm enhancement techniques
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