High frequency diffraction of an electromagnetic plane wave by an imperfectly conducting rectangular cylinder

Copyright @ 2011 IEEEWe shall consider the the problem of determining the scattered far wave field produced when a plane E-polarized wave is incident on an imperfectly conducting rectangular cylinder. By using the the uniform asymptotic solution for the problem of the diffraction of a plane wave by a right-angled impedance wedge, in conjunction with Keller's method, the a high frequency far field solution to the problem is given

Joint Communication and Sensing Design in Coal Mine Safety Monitoring: 3D Phase Beamforming for RIS-Assisted Wireless Networks

This paper investigates the resource allocation of a reconfigurable intelligent surface (RIS)-aided joint communication and sensing (JCAS) system in a coal mine scenario. In the JCAS system, an RIS is implemented at the corner of the zigzag tunnels to improve the complicated wireless environment, where ground obstacles frequently block direct links. In addition, a wireless backhaul base station with a limited energy budget is deployed in the depth of the mine to sense the target area and provide internet of things (IoT) services and communication services for users. Furthermore, a data center is placed on the ground to analyze the obtained data and route the communication data. Under this deployment, a joint optimization problem of RIS phase shift matrix, RIS element switches, and area sensing time is proposed. We aim to maximize the successful sensed bits under total completion time, and maximum transmit power constraints. In order to solve this problem, an iterative algorithm is proposed. The successive convex approximation (SCA) based algorithm is used for the RIS phase shift matrix optimization subproblem. For the sensing time optimization subproblem, the quadratic approximation method is proposed to optimize the number of area perceptions. The coordinate descent method is utilized to optimize the RIS element switches. Simulation results show that the energy efficiency is improved by up to 38%, and 7% increases the specific data size compared with the benchmark solutions

Criteria for the use of omics-based predictors in clinical trials.

The US National Cancer Institute (NCI), in collaboration with scientists representing multiple areas of expertise relevant to 'omics'-based test development, has developed a checklist of criteria that can be used to determine the readiness of omics-based tests for guiding patient care in clinical trials. The checklist criteria cover issues relating to specimens, assays, mathematical modelling, clinical trial design, and ethical, legal and regulatory aspects. Funding bodies and journals are encouraged to consider the checklist, which they may find useful for assessing study quality and evidence strength. The checklist will be used to evaluate proposals for NCI-sponsored clinical trials in which omics tests will be used to guide therapy

Use of the new World Health Organization child growth standards to describe longitudinal growth of breastfed rural Bangladeshi infants and young children.

BACKGROUND: Although the National Center for Health Statistics (NCHS) reference has been widely used, in 2006 the World Health Organization (WHO) released new standards for assessing growth of infants and children worldwide. OBJECTIVE: To assess and compare the growth of breastfed rural Bangladeshi infants and young children based on the new WHO child growth standards and the NCHS reference. METHODS: We followed 1343 children in the Maternal and Infant Nutrition Intervention in Matlab (MINIMat) study from birth to 24 months of age. Weights and lengths of the children were measured monthly during infancy and quarterly in the second year of life. Anthropometric indices were calculated using both WHO standards and the NCHS reference. The growth pattern and estimates of undernutrition based on the WHO standards and the NCHS reference were compared. RESULTS: The mean birthweight was 2697 +/- 401 g, with 30% weighing <2500 g. The growth pattern of the MINIMat children more closely tracked the WHO standards than it did the NCHS reference. The rates of stunting based on the WHO standards were higher than the rates based on the NCHS reference throughout the first 24 months. The rates of underweight and wasting based on the WHO standards were significantly different from those based on the NCHS reference. CONCLUSIONS: This comparison confirms that use of the NCHS reference misidentifies undernutrition and the timing of growth faltering in infants and young children, which was a key rationale for constructing the new WHO standards. The new WHO child growth standards provide a benchmark for assessing the growth of breastfed infants and children

Blood spots as an alternative to whole blood collection and the effect of a small monetary incentive to increase participation in genetic association studies

<p>Abstract</p> <p>Background</p> <p>Collection of buccal cells from saliva for DNA extraction offers a less invasive and convenient alternative to venipuncture blood collection that may increase participation in genetic epidemiologic studies. However, dried blood spot collection, which is also a convenient method, offers a means of collecting peripheral blood samples from which analytes in addition to DNA can be obtained.</p> <p>Methods</p> <p>To determine if offering blood spot collection would increase participation in genetic epidemiologic studies, we conducted a study of collecting dried blood spot cards by mail from a sample of female cancer cases (n = 134) and controls (n = 256) who were previously selected for a breast cancer genetics study and declined to provide a venipuncture blood sample. Participants were also randomized to receive either a $2.00 bill or no incentive with the blood spot collection kits.</p> <p>Results</p> <p>The average time between the venipuncture sample refusal and recruitment for the blood spot collection was 4.4 years. Thirty-seven percent of cases and 28$2.00 incentive vs. 26% for no incentive, p = 0.6), it was significantly associated with participation among the breast cancer cases (48% vs. 27%, respectively, p = 0.01). There did not appear to be any bias in response since no differences between cases and controls and incentive groups were observed when examining several demographic, work history and radiation exposure variables.</p> <p>Conclusion</p> <p>This study demonstrates that collection of dried blood spot cards in addition to venipuncture blood samples may be a feasible method to increase participation in genetic case-control studies.</p

Deaths among tuberculosis cases in Shanghai, China: who is at risk?

<p>Abstract</p> <p>Background</p> <p>Information about the risk factors associated with death caused by tuberculosis (TB) or death with TB would allow improvements in the clinical care of TB patients and save lives. The present study sought to identify characteristics associated with increased risk of death during anti-TB treatment in Shanghai, a city in China with one of the country's highest TB mortality rates.</p> <p>Methods</p> <p>We evaluated deaths among culture positive pulmonary TB cases that were diagnosed in Shanghai during 2000–2004 and initiated anti-TB therapy. Demographic, clinical, mycobacteriological information and treatment outcomes were routinely collected through a mandatory reporting system.</p> <p>Results</p> <p>There were 7,999 culture positive pulmonary cases reported during the study period. The overall case fatality rate was 5.5% (440 cases), and approximately half (50.5%) of the deaths were attributed to causes other than TB. Eighty-six percent of the deaths were among TB cases age ≥ 60 years. The significant independent risk factors for mortality during anti-TB treatment were advancing age, male sex, sputum smear positivity, and the presence of a comorbidity.</p> <p>Conclusion</p> <p>More vigorous clinical management and prevention strategies by both the TB control program and other public health programs are essential to improve TB treatment outcomes. Earlier suspicion, diagnosis and treatment of TB, especially among persons older than 60 years of age and those with a comorbid condition, could reduce deaths among TB patients.</p

Genetic polymorphisms of DNA double strand break gene Ku70 and gastric cancer in Taiwan

<p>Abstract</p> <p>Background and aim</p> <p>The DNA repair gene <it>Ku70</it>, an important member of non-homologous end-joining repair system, is thought to play an important role in the repairing of DNA double strand breaks. It is known that defects in double strand break repair capacity can lead to irreversible genomic instability. However, the polymorphic variants of <it>Ku70</it>, have never been reported about their association with gastric cancer susceptibility.</p> <p>Methods</p> <p>In this hospital-based case-control study, the associations of <it>Ku70 </it>promoter T-991C (rs5751129), promoter G-57C (rs2267437), promoter A-31G (rs132770), and intron 3 (rs132774) polymorphisms with gastric cancer risk in a Taiwanese population were investigated. In total, 136 patients with gastric cancer and 560 age- and gender-matched healthy controls recruited from the China Medical Hospital in Taiwan were genotyped.</p> <p>Results</p> <p>As for <it>Ku70 </it>promoter T-991C, the ORs after adjusted by age and gender of the people carrying TC and CC genotypes were 2.41 (95% CI = 1.53-3.88) and 3.21 (95% CI = 0.96-9.41) respectively, compared to those carrying TT wild-type genotype. The <it>P </it>for trend was significant (<it>P </it>< 0.0001). In the dominant model (TC plus CC versus TT), the association between <it>Ku70 </it>promoter T-991C polymorphism and the risk for gastric cancer was also significant (adjusted OR = 2.48, 95% CI = 1.74-3.92). When stratified by age and gender, the association was restricted to those at the age of 55 or elder of age (TC vs TT: adjusted OR = 2.52, 95% CI = 1.37-4.68, <it>P </it>= 0.0139) and male (TC vs TT: adjusted OR = 2.58, 95% CI = 1.33-4.47, <it>P </it>= 0.0085). As for the other three polymorphisms, there was no difference between both groups in the distributions of their genotype frequencies.</p> <p>Conclusion</p> <p>In conclusion, the <it>Ku70 </it>promoter T-991C (rs5751129), but not the <it>Ku70 </it>promoter C-57G (rs2267437), promoter A-31G (rs132770) or intron 3 (rs132774), is associated with gastric cancer susceptibility. This polymorphism may be a novel useful marker for gastric carcinogenesis.</p

Practice Models and Challenges in Teledermatology: A Study of Collective Experiences from Teledermatologists

Despite increasing practice of teledermatology in the U.S., teledermatology practice models and real-world challenges are rarely studied.The primary objective was to examine teledermatology practice models and shared challenges among teledermatologists in California, focusing on practice operations, reimbursement considerations, barriers to sustainability, and incentives. We conducted in-depth interviews with teledermatologists that practiced store-and-forward or live-interactive teledermatology from January 1, 2007 through March 30, 2011 in California.Seventeen teledermatologists from academia, private practice, health maintenance organizations, and county settings participated in the study. Among them, 76% practiced store-and-forward only, 6% practiced live-interactive only, and 18% practiced both modalities. Only 29% received structured training in teledermatology. The average number of years practicing teledermatology was 4.29 years (SD±2.81). Approximately 47% of teledermatologists served at least one Federally Qualified Health Center. Over 75% of patients seen via teledermatology were at or below 200% federal poverty level and usually lived in rural regions without dermatologist access. Practice challenges were identified in the following areas. Teledermatologists faced delays in reimbursements and non-reimbursement of teledermatology services. The primary reason for operational inefficiency was poor image quality and/or inadequate history. Costly and inefficient software platforms and lack of communication with referring providers also presented barriers.Teledermatology enables underserved populations to access specialty care. Improvements in reimbursement mechanisms, efficient technology platforms, communication with referring providers, and teledermatology training are necessary to support sustainable practices

Molecular Basis of NDM-1, a New Antibiotic Resistance Determinant

The New Delhi Metallo-β-lactamase (NDM-1) was first reported in 2009 in a Swedish patient. A recent study reported that Klebsiella pneumonia NDM-1 positive strain or Escherichia coli NDM-1 positive strain was highly resistant to all antibiotics tested except tigecycline and colistin. These can no longer be relied on to treat infections and therefore, NDM-1 now becomes potentially a major global health threat

Schizophrenia-associated HapICE haplotype is associated with increased NRG1 type III expression and high nucleotide diversity

Excitement and controversy have followed neuregulin (NRG1) since its discovery as a putative schizophrenia susceptibility gene; however, the mechanism of action of the associated risk haplotype (HapICE) has not been identified, and specific genetic variations, which may increase risk to schizophrenia have remained elusive. Using a postmortem brain cohort from 37 schizophrenia cases and 37 controls, we resequenced upstream of the type I–IV promoters, and the HapICE repeat regions in intron 1. Relative abundance of seven NRG1 mRNA transcripts in the prefrontal cortex were determined and compared across diagnostic and genotypic groups. We identified 26 novel DNA variants and showed an increased novel variant load in cases compared with controls (χ2=7.815; P=0.05). The average nucleotide diversity (θ=10.0 × 10−4) was approximately twofold higher than that previously reported for BDNF, indicating that NRG1 may be particularly prone to genetic change. A greater nucleotide diversity was observed in the HapICE linkage disequilibrium block in schizophrenia cases (θ(case)=13.2 × 10−4; θ(control)=10.0 × 10−4). The specific HapICE risk haplotype was associated with increased type III mRNA (F=3.76, P=0.028), which in turn, was correlated with an earlier age of onset (r=−0.343, P=0.038). We found a novel intronic five-SNP haplotype ∼730 kb upstream of the type I promoter and determined that this region functions as transcriptional enhancer that is suppressed by SRY. We propose that the HapICE risk haplotype increases expression of the most brain-abundant form of NRG1, which in turn, elicits an earlier clinical presentation, thus providing a novel mechanism through which this genetic association may increase risk of schizophrenia