Multi-wave-mixing-induced nonlinear modulation of diffraction peaks in an opto-atomic grating.

We propose an atomic model in close-loop configuration, which exhibits controllable symmetric and asymmetric evolution of significantly enhanced diffraction peaks of the weak probe beam in an opto-atomic grating at far-field regime. Such results are obtained by the linear and nonlinear modulation of the intensities of the diffraction peaks as a result of multi-wave-mixing-induced modification of spatially modulated coherence in a closed four-level atomic system. Novelty of the results lies in predicting the diffraction pattern with uniform peak height due to the dominance of the amplitude part of the grating-transfer-function at the condition of exact atom-field resonance, which is unique to the present model. Efficacy of the present scheme is to apply it in producing nonlinear light generated by four-wave-mixing-induced control of spatially modulated coherence effect. The work also finds its importance for its applicability in the field of all-optical devices.

Optical absorption microscopy of localized atoms at microwave domain: two-dimensional localization based on the projection of three-dimensional localization.

A new approach for achieving two - dimensional (2D) atom localization microscopy based on the projection of three - dimensional (3D) localization in the plane of the detector is described in the present work. Spatial variation of the position-dependent 2D-localization pattern in the xy-plane is obtained with the shifting of the position of the detector along the z-axis under the parallel- and cross- axis configurations of the standing-wave fields. An attempt is made to study the 2D-localization characteristics in the specific parametric conditions for which the localization structures evolve with different shapes eventually leading to 100% detection probability of the atom both in the sub-wavelength and sub-half-wavelength regimes. The scope of tuning the cross-axis configuration over a wide range adds novelty and robustness to this model. Apart from the 2D-localization, various localization patterns with eight- to single-peak structures appear as interesting outcomes through the efficient manipulation of control parameters in the study of one-dimensional (1D) atom localization. The application of the traveling-wave field or its equivalent appears to be unique in achieving high-precision localization with maximal probability (100%) in both the 1D and 2D field-configuration schemes. Proper tuning of the traveling wave accompanied by the standing wave in the 1D scheme results in the single-peak localization in the sub-half-wavelength range. As a whole, the present work seems to be very much efficient for high-precision optical lithography.

Primary or specialist medical care: Which is more equitable? A policy brief.

BACKGROUND: Equity in health and equitable access to healthcare has been at the core of health policy in India. The key policy challenge has been how to make that possible? Various health insurance schemes such as the Rashtriya Swasthya Bima Yojana and Arogyasri seek to improve poor people's access to specialist medical care in the public and private sectors. On the other hand, access to primary medical care has been left to the supply side interventions. METHODS: We did a focused review of evidence on equity aspects of primary medical care versus specialist medical care. We selected relevant publications from the Cochrane Library, PubMed and Google Scholar searches and articles snowballing out of them. RESULTS: Higher primary care physician-to-population ratio is invariably associated with better health outcomes. Primary care may partly protect the poor from adverse effects of income inequality on health status. On the other hand, populations do not necessarily benefit from an overabundance of specialists in a geographical area. CONCLUSIONS: Three key policy lessons emerge from this review. First, states should strengthen primary medical care by upgrading health centres. Second, a family health protection plan should be introduced as a demand side intervention to deliver primary care through health centres, non-profit and for-profit clinics. Third, postgraduate courses in family medicine should be introduced for a balanced development of the specialty of primary care pari passu other specialties.

The need for evidence-based public health response in disasters.

AIM: Broad outline of this paper was presented at the Evidence Aid Symposium, on 20 Sep 2014, at Hyderabad, India, before the 22nd Cochrane Colloquium. METHODS: Survey of the field and review of literature. RESULTS: Response to disasters is usually vulnerable to myths and misconceptions. Effective healthcare response requires evidence and information to meet various and often unpredictable eventualities. The knowledge base should facilitate rapid assessment of adverse health outcomes, availability healthcare infrastructure, appropriate organizational strategies, and selection of feasible medical interventions to deal with any given disaster. Most rapid surveys have to adopt some stratification and a cluster sampling design for representativeness. Qualitative research methods are useful to study organizational challenges. Adequate and accurate description of the context is important for interpretation of organization behavior studies. Testing efficacy of medical interventions by randomized trials is usually difficult, unless feasible study designs are planned in advance and ready for execution at short notice. A lot of disaster healthcare research literature is based on surveys and case studies, as these are more feasible. Hence, systematic reviews ought to rate the level of evidence from qualitative studies and adequately summarize the context of case studies. CONCLUSIONS: Research on health response to disaster has picked up momentum only recently in the 21(st) century. There is also a need to develop disaster healthcare research capacities to address regional vulnerabilities. Generating evidence is not enough. Concerted societal action is needed to sensitize, train, and equip adequate human resources to fill in various key emergency medical and public health roles when disaster strikes.

Job satisfaction and motivation of health workers in public and private sectors: cross-sectional analysis from two Indian states.

BACKGROUND: Ensuring health worker job satisfaction and motivation are important if health workers are to be retained and effectively deliver health services in many developing countries, whether they work in the public or private sector. The objectives of the paper are to identify important aspects of health worker satisfaction and motivation in two Indian states working in public and private sectors. METHODS: Cross-sectional surveys of 1916 public and private sector health workers in Andhra Pradesh and Uttar Pradesh, India, were conducted using a standardized instrument to identify health workers' satisfaction with key work factors related to motivation. Ratings were compared with how important health workers consider these factors. RESULTS: There was high variability in the ratings for areas of satisfaction and motivation across the different practice settings, but there were also commonalities. Four groups of factors were identified, with those relating to job content and work environment viewed as the most important characteristics of the ideal job, and rated higher than a good income. In both states, public sector health workers rated "good employment benefits" as significantly more important than private sector workers, as well as a "superior who recognizes work". There were large differences in whether these factors were considered present on the job, particularly between public and private sector health workers in Uttar Pradesh, where the public sector fared consistently lower (P < 0.01). Discordance between what motivational factors health workers considered important and their perceptions of actual presence of these factors were also highest in Uttar Pradesh in the public sector, where all 17 items had greater discordance for public sector workers than for workers in the private sector (P < 0.001). CONCLUSION: There are common areas of health worker motivation that should be considered by managers and policy makers, particularly the importance of non-financial motivators such as working environment and skill development opportunities. But managers also need to focus on the importance of locally assessing conditions and managing incentives to ensure health workers are motivated in their work.

Multiplex PCR technique could be an alternative approach for early detection of leprosy among close contacts--a pilot study from India.

BACKGROUND: Implementation of Multi drug Therapy (MDT) regimen has resulted in the decline of the total number of leprosy cases in the world. Though the prevalence rate has been declining, the incidence rate remains more or less constant and high in South East Asian countries particularly in India, Nepal, Bangladesh, Pakistan and Srilanka. Leprosy, particularly that of multibacillary type spreads silently before it is clinically detected. An early detection and treatment would help to prevent transmission in the community. Multiplex PCR (M-PCR) technique appears to be promising towards early detection among contacts of leprosy cases. METHODS: A total of 234 paucibacillary (PB) and 205 multibacillary (MB) leprosy cases were studied in a community of an endemic area of Bankura district of West Bengal (Eastern India). They were assessed by smear examination for acid-fast bacilli (AFB) and M-PCR technique. These patients were treated with Multidrug Therapy (MDT) as prescribed by WHO following detection. A total of 110 MB and 72 PB contacts were studied by performing M-PCR in their nasal swab samples. RESULTS: 83.4% of MB patients were observed to be positive by smear examination for AFB and 89.2% by M-PCR. While 22.2% of PB patients were found to be positive by smear examination for AFB, 80.3% of these patients were positive by M-PCR. Among leprosy contacts (using M-PCR), 10.9% were found to be positive among MB contacts and 1.3% among PB contacts. Interestingly, two contacts of M-PCR positive MB cases developed leprosy during the period of two years follow up. CONCLUSION: The M-PCR technique appears to be an efficient tool for early detection of leprosy cases in community based contact tracing amongst close associates of PB and MB cases. Early contact tracing using a molecular biology tool can be of great help in curbing the incidence of leprosy further.

Is fecal contamination of drinking water after collection associated with household water handling and hygiene practices? A study of urban slum households in Hyderabad, India.

Water-borne illness, primarily caused by fecal contamination of drinking water, is a major health burden in the state of Andhra Pradesh, India. Currently drinking water is treated at the reservoir level and supplied on alternate days, necessitating storage in households for up to 48 hrs. We hypothesized that fecal contamination occurs principally during storage due to poor water handling. In this study we tested for coliform bacteria in water samples collected at distribution points as household storage containers were filled, and then tested containers in the same households 24-36 hours after collection. We also conducted an observational survey to make an assessment of water handling and hygiene. Ninety-two percent (47/51) of samples tested at supply points were adequately chlorinated and bacterial contamination was found in two samples with no residual chlorine. Samples collected from household storage containers showed an increase in contamination in 18/50 houses (36%). Households with contaminated stored samples did not show significant differences in demographics, water handling, hygiene practices, or sanitation. Nevertheless, the dramatic increase in contamination after collection indicates that until an uninterrupted water supply is possible, the point at which the biggest health impact can be made is at the household level.

Civil registration systems and vital statistics: successes and missed opportunities.

Vital statistics generated through civil registration systems are the major source of continuous monitoring of births and deaths over time. The usefulness of vital statistics depends on their quality. In the second paper in this Series we propose a comprehensive and practical framework for assessment of the quality of vital statistics. With use of routine reports to the UN and cause-of-death data reported to WHO, we review the present situation and past trends of vital statistics in the world and note little improvement in worldwide availability of general vital statistics or cause-of-death statistics. Only a few developing countries have been able to improve their civil registration and vital statistics systems in the past 50 years. International efforts to improve comparability of vital statistics seem to be effective, and there is reasonable progress in collection and publication of data. However, worldwide efforts to improve data have been limited to sporadic and short-term measures. We conclude that countries and developmental partners have not recognised that civil registration systems are a priority.