Wideband Matching of Full-Wavelength Dipole with Reflector for Base Station

© 1963-2012 IEEE. This communication introduces a wideband hybrid feeding method for full-wavelength dipole antennas with a reflector. A full-wavelength dipole is designed to cover the band from 698 to 960 MHz for cellular base station applications. Its matching circuit consists of a triple-tuned circuit and a quasi-quarter-wavelength impedance transformer. The proposed matching circuit can provide balanced feeding as a balun and has a compact size. The working mechanism and a complete design scheme of the proposed matching circuit are elaborated. The matching circuit is designed and optimized using a circuit theory model and then physically realized using microstrip lines based on full-wave simulation. The measured reflection coefficient |S-{11}| is lesser than -14 dB across the entire band from 698 to 960 MHz, exhibiting a bandwidth of 32%. This is the first time that a wideband center-fed full-wavelength dipole is proposed

Linking international clinical research with stateless populations to justice in global health

BACKGROUND: In response to calls to expand the scope of research ethics to address justice in global health, recent scholarship has sought to clarify how external research actors from high-income countries might discharge their obligation to reduce health disparities between and within countries. An ethical framework-'research for health justice'-was derived from a theory of justice (the health capability paradigm) and specifies how international clinical research might contribute to improved health and research capacity in host communities. This paper examines whether and how external funders, sponsors, and researchers can fulfill their obligations under the framework. METHODS: Case study research was undertaken on the Shoklo Malaria Research Unit's (SMRU) vivax malaria treatment trial, which was performed on the Thai-Myanmar border with Karen and Myanmar refugees and migrants. We conducted nineteen in-depth interviews with trial stakeholders, including investigators, trial participants, community advisory board members, and funder representatives; directly observed at trial sites over a five-week period; and collected trial-related documents for analysis. RESULTS: The vivax malaria treatment trial drew attention to contextual features that, when present, rendered the 'research for health justice' framework's guidance partially incomplete. These insights allowed us to extend the framework to consider external research actors' obligations to stateless populations. Data analysis then showed that framework requirements are largely fulfilled in relation to the vivax malaria treatment trial by Wellcome Trust (funder), Oxford University (sponsor), and investigators. At the same time, this study demonstrates that it may be difficult for long-term collaborations to shift the focus of their research agendas in accordance with the changing burden of illness in their host communities and to build the independent research capacity of host populations when working with refugees and migrants. Obstructive factors included the research funding environment and staff turnover due to resettlement or migration. CONCLUSIONS: Our findings show that obligations for selecting research targets, research capacity strengthening, and post-trial benefits that link clinical trials to justice in global health can be upheld by external research actors from high-income countries when working with stateless populations in LMICs. However, meeting certain framework requirements for long-term collaborations may not be entirely feasible

Spectroscopie de vibration infrarouge du silicium amorphe hydrogéné évaporé

Ce travail porte sur l’étude des configurations des liaisons Si-H des couches minces du silicium amorphe hydrogéné évaporé (a-Si:H) préparées dans un bâti ultra-vide (UHV). L’hydrogène atomique est obtenu à l’aide d’un plasma dans un tube à décharge dirigé vers le porte-substrat. Les fréquences de vibrations et la nature des liaisons Si-H ont été analysées à partir des mesures de spectroscopie infrarouge à transformée de Fourier.Mots-clés : silicium amorphe hydrogéné, absorption infrarouge, transformée de Fourie

Wideband feeding method for full-wave dipole

© 2017 IEEE. This paper introduces a wide-band feeding method for full-wave dipole antennas. A full-wave dipole is designed to cover the band from 698 MHz to 960 MHz for cellular base station applications. Its matching circuit consists of a laddertype filter design and a quasi-quarter-wavelength resistance transformer. The proposed matching circuit can provide balanced feeding as a balun and has a compact size. The matching circuit is designed and optimized using a circuit theory model and then physically realized using microstrip lines based on full-wave simulation. The simulated reflection coefficient |S11| is < -15 dB across the entire target band, exhibiting a bandwidth of 32%

A Step Toward Workplace Obesity Prevention: Evaluation of Weight Management Program for Hospital-based Health Care Providers

Background: Obesity is a worldwide problem. Healthy workplace and lifestyle are crucial in preventing obesity. A workplace weight management program could create a culture of health and facilitate weight control among health care providers. The present study aims to describe and evaluate the health outcomes of the interaction of professional practice and organizational infrastructure. Method: The hospital-based weight management program was an eight-week pilot randomized controlled study for obese health care providers. The primary outcomes were body weight and body mass index. The secondary outcomes included serum fasting glucose, fasting cholesterol, triglyceride, high- and low-density lipoprotein, body fat percentage, body mass, and quality of life. The RE-AIM framework was used to examine the intervention’s reach, effectiveness, adoption, implementation and maintenance at individual and organizational levels. Results: The program successfully attained the target population. Health care providers demonstrated short-term weight loss and decreased serum fasting cholesterol level after completing the program. The excellent retention rate (95%) of the study suggested that the participants were well-engaged in self-weight management. The program was implemented with adequate resource and support from the health organization. The organization may consider continuing the program in view of its long-term benefits to health care providers. Conclusion: Supportive organizational structure and culture enhanced professional practice and improved the health outcomes of the hospital-based weight management program participants

Identification of potential CepR regulated genes using a cep box motif-based search of the Burkholderia cenocepacia genome

BACKGROUND: The Burkholderia cenocepacia CepIR quorum sensing system has been shown to positively and negatively regulate genes involved in siderophore production, protease expression, motility, biofilm formation and virulence. In this study, two approaches were used to identify genes regulated by the CepIR quorum sensing system. Transposon mutagenesis was used to create lacZ promoter fusions in a cepI mutant that were screened for differential expression in the presence of N-acylhomoserine lactones. A bioinformatics approach was used to screen the B. cenocepacia J2315 genome for CepR binding site motifs. RESULTS: Four positively regulated and two negatively regulated genes were identified by transposon mutagenesis including genes potentially involved in iron transport and virulence. The promoter regions of selected CepR regulated genes and site directed mutagenesis of the cepI promoter were used to predict a consensus cep box sequence for CepR binding. The first-generation consensus sequence for the cep box was used to identify putative cep boxes in the genome sequence. Eight potential CepR regulated genes were chosen and the expression of their promoters analyzed. Six of the eight were shown to be regulated by CepR. A second generation motif was created from the promoters of these six genes in combination with the promoters of cepI, zmpA, and two of the CepR regulated genes identified by transposon mutagenesis. A search of the B. cenocepacia J2315 genome with the new motif identified 55 cep boxes in 65 promoter regions that may be regulated by CepR. CONCLUSION: Using transposon mutagenesis and bioinformatics expression of twelve new genes have been determined to be regulated by the CepIR quorum sensing system. A cep box consensus sequence has been developed based on the predicted cep boxes of ten CepR regulated genes. This consensus cep box has led to the identification of over 50 new genes potentially regulated by the CepIR quorum sensing system

Système temps réel de lever précis de la géométrie des axes routiers

Le développement de la télématique des transports routiers réclame des données géographiques de premier ordre. Les systèmes de mobile mapping peuvent acquérir ces informations en offrant une productivité incomparable grâce à la combinaison de capteurs de localisation et de vidéogrammétrie. Le laboratoire de Topométrie de l’EPFL a développé le système Photobus qui permet de lever la géométrie des axes routiers avec une très haute qualité. Cet article présente l’architecture et les composants principaux de cette plateforme de mobile mapping : un instrument de localisation de grande précision basé sur la localisation par satellites et un système de caméra numérique basé sur la technologie CMOS. L’article présente quelques résultats issus d’une campagne de mesures, dont la précision planimétrique est de l’ordre de 10 cm