9,122 research outputs found

    Geodesics, retracts, and the norm-preserving extension property in the symmetrized bidisc

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    A set in a domain in has the norm-preserving extension property if every bounded holomorphic function on has a holomorphic extension to with the same supremum norm. We prove that an algebraic subset of the symmetrized bidischas the norm-preserving extension property if and only if it is either a singleton, itself, a complex geodesic of , or the union of the set and a complex geodesic of degree in . We also prove that the complex geodesics in coincide with the nontrivial holomorphic retracts in . Thus, in contrast to the case of the ball or the bidisc, there are sets in which have the norm-preserving extension property but are not holomorphic retracts of . In the course of the proof we obtain a detailed classification of the complex geodesics in modulo automorphisms of . We give applications to von Neumann-type inequalities for -contractions (that is, commuting pairs of operators for which the closure of is a spectral set) and for symmetric functions of commuting pairs of contractive operators. We find three other domains that contain sets with the norm-preserving extension property which are not retracts: they are the spectral ball of matrices, the tetrablock and the pentablock. We also identify the subsets of the bidisc which have the norm-preserving extension property for symmetric functions

    Revisiting the quality of Health Extension Workers’ training: Case study from Amhara Region, Ethiopia

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    Background:- Ethiopia has been training community health workers, locally under its program of Health Extension Workers, in Technical and Vocational Education and Training Institutions (TVETI) since 2003.Objective:- To examine conditions that may affect the quality of health extension workers training in Ethiopia.Methods:- We conducted a qualitative case study interviewing 32 informants. This approach helped us get insight into the subject from different perspectives. The staffs of two institutions and the Amhara Region Health Bureau, and health extension workers were involved in the study. Data collected were analyzed through an interpretative approach.Results:- The study showed that the curriculum for the training had not been revised since it was developed. Shortage of teaching facilities and on-the-job training of teachers were also identified as constraints.Conclusion:- The curriculum should be revised and more time allotted for practicum and improved training facilities are needed for this purpose. Teachers need to continue updating themselves and their skills. Better collaboration between the training institutions and the health system is necessary for enhancing the quality of health extension workers training. [Ethiop. J. Health Dev. 2011; 25(3):201-205

    Physico-chemical and microbiological characteristics of honey from the sudano-guinean zone of West Cameroon

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    The physico-chemical and microbiological characteristics of honey from the sudano-guinean zone of West Cameroon were determined. The indices obtained were within their respective ranges recorded forhoney in temperate countries, except for calcium content whose value was on the upper side of its reference range. A bacterial type and eight fungi species contamination were found to have contaminated the honey from the local markets. However, there were no microbes present in honey harvested from the Bee Research Farm of the University of Dschang. This indicated contamination from secondary sources, during handling and or adulterations of honey from our local markets. Honey used in this study showed medium crystallisation tendency and granulation was faster when stored under dark than light at similar conditions. The mixed floral or nectar sources, fluctuating environmental conditions and processing procedures played major roles in the physico-chemical differences observed between the local and temperate honeys

    Effect of demographic variables on public attitudes towards genetically modified insulin

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    Earlier studies on public attitude and risk perception have concluded that the public’s attitudes towards biotechnology was primarily driven by several factors such as familiarity, perceived benefits, perceived risks, risk acceptance, moral concerns and encouragement. Demographic characteristics have been known to affect attitudes towards science. The purpose of this paper is to compare the attitude of the Malaysian public towards genetically modified (GM) insulin across several background variables such as religion, race, education level and age. A survey was carried out on 1017 respondents stratified according to various stakeholder groups in the Klang Valley region. Analyses of Variance (ANOVAs) showed significant differences in the mean scores for familiarity of GM insulin across religions, races and ages but not across education levels and gender. Both perceived benefits and perceived risks were found to differ across races, education levels and gender but not across religions and ages. On the other hand, moral concern was found to differ in all four background variables except gender while risk acceptance differed across races and gender and encouragement only differed across education  levels. In conclusion, background variables do have a significant effect on some of the dimensions of Malaysians’ attitudes towards modern biotechnology. The research findings will be useful for understanding the effect of background variables on public attitudes towards the application of gene technology in medicine. More in-depth empirical studies should be carried out to understand the underlying causes behind the differences.Key words: Attitude, gene technology, medicine, GM (genetically modified) insulin, background variables, Malaysia

    Evaluation of health workforce competence in maternal and neonatal issues in public health sector of Pakistan: an Assessment of their training needs

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    <p>Abstract</p> <p>Background</p> <p>More than 450 newborns die every hour worldwide, before they reach the age of four weeks (neonatal period) and over 500,000 women die from complications related to childbirth. The major direct causes of neonatal death are infections (36%), Prematurity (28%) and Asphyxia (23%). Pakistan has one of the highest perinatal and neonatal mortality rates in the region and contributes significantly to global neonatal mortality. The high mortality rates are partially attributable to scarcity of trained skilled birth attendants and paucity of resources. Empowerment of health care providers with adequate knowledge and skills can serve as instrument of change.</p> <p>Methods</p> <p>We carried out training needs assessment analysis in the public health sector of Pakistan to recognize gaps in the processes and quality of MNCH care provided. An assessment of Knowledge, Attitude, and Practices of Health Care Providers on key aspects was evaluated through a standardized pragmatic approach. Meticulously designed tools were tested on three tiers of health care personnel providing MNCH in the community and across the public health care system. The Lady Health Workers (LHWs) form the first tier of trained cadre that provides MNCH at primary care level (BHU) and in the community. The Lady Health Visitor (LHVs), Nurses, midwives) cadre follow next and provide facility based MNCH care at secondary and tertiary level (RHCs, Taluka/Tehsil, and DHQ Hospitals). The physician/doctor is the specialized cadre that forms the third tier of health care providers positioned in secondary and tertiary care hospitals (Taluka/Tehsil and DHQ Hospitals). The evaluation tools were designed to provide quantitative estimates across various domains of knowledge and skills. A priori thresholds were established for performance rating.</p> <p>Results</p> <p>The performance of LHWs in knowledge of MNCH was good with 30% scoring more than 70%. The Medical officers (MOs), in comparison, performed poorly in their knowledge of MNCH with only 6% scoring more than 70%. All three cadres of health care providers performed poorly in the resuscitation skill and only 50% were able to demonstrate steps of immediate newborn care. The MOs performed far better in counselling skills compare to the LHWs. Only 50 per cent of LHWs could secure competency scale in this critical component of skills assessment.</p> <p>Conclusions</p> <p>All three cadres of health care providers performed well below competency levels for MNCH knowledge and skills. Standardized training and counselling modules, tailored to the needs and resources at district level need to be developed and implemented. This evaluation highlighted the need for periodic assessment of health worker training and skills to address gaps and develop targeted continuing education modules. To achieve MDG4 and 5 goals, it is imperative that such deficiencies are identified and addressed.</p

    Markerless attenuation correction for carotid MRI surface receiver coils in combined PET/MR imaging.

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    The purpose of the study was to evaluate the effect of attenuation of MR coils on quantitative carotid PET/MR exams. Additionally, an automated attenuation correction method for flexible carotid MR coils was developed and evaluated.The attenuation of the carotid coil was measured by imaging a uniform water phantom injected with 37 MBq of 18F-FDG in a combined PET/MR scanner for 24 min with and without the coil. In the same session, an ultra-short echo time (UTE) image of the coil on top of the phantom was acquired. Using a combination of rigid and non-rigid registration, a CT-based attenuation map was registered to the UTE image of the coil for attenuation and scatter correction. After phantom validation, the effect of the carotid coil attenuation and the attenuation correction method were evaluated in five subjects.Phantom studies indicated that the overall loss of PET counts due to the coil was 6.3% with local region-of-interest (ROI) errors reaching up to 18.8%. Our registration method to correct for attenuation from the coil decreased the global error and local error (ROI) to 0.8% and 3.8%, respectively. The proposed registration method accurately captured the location and shape of the coil with a maximum spatial error of 2.6 mm. Quantitative analysis in human studies correlated with the phantom findings, but was dependent on the size of the ROI used in the analysis.MR coils result in significant error in PET quantification and thus attenuation correction is needed. The proposed strategy provides an operator-free method for attenuation and scatter correction for a flexible MRI carotid surface coil for routine clinical use

    A holistic mathematical modelling and simulation for cathodic delamination mechanism – a novel and an efficient approach

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    This paper addresses a holistic mathematical design using a novel approach for understanding the mechanism of cathodic delamination. The approach employed a set of interdependent parallel processes with each process representing: cation formation, oxygen reduction and cation transport mechanism, respectively. Novel mathematical equations have been developed for each of the processes based on the observations recorded from experimentation. These equations are then solved using efficient time-iterated algorithms. Each process consists of distinct algorithms which communicate with each other using duplex channels carrying signals. Each signal represents a distinct delamination parameter. As a result of interdependency of various processes and their parallel behaviour, it is much easier to analyse the quantitative agreement between various delamination parameters. The developed modelling approach provides an efficient and reliable prediction method for the delamination failure. The results obtained are in good agreement with the previously reported experimental interpretations and numerical results. This model provides a foundation for the future research within the area of coating failure analysis and prediction

    Enhancement of the Nernst effect by stripe order in a high-Tc superconductor

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    The Nernst effect in metals is highly sensitive to two kinds of phase transition: superconductivity and density-wave order. The large positive Nernst signal observed in hole-doped high-Tc superconductors above their transition temperature Tc has so far been attributed to fluctuating superconductivity. Here we show that in some of these materials the large Nernst signal is in fact caused by stripe order, a form of spin / charge modulation which causes a reconstruction of the Fermi surface. In LSCO doped with Nd or Eu, the onset of stripe order causes the Nernst signal to go from small and negative to large and positive, as revealed either by lowering the hole concentration across the quantum critical point in Nd-LSCO, or lowering the temperature across the ordering temperature in Eu-LSCO. In the latter case, two separate peaks are resolved, respectively associated with the onset of stripe order at high temperature and superconductivity near Tc. This sensitivity to Fermi-surface reconstruction makes the Nernst effect a promising probe of broken symmetry in high-Tc superconductors
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