52 research outputs found

    Scattering of massive Dirac particles by a Kink-like potential

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    The scattering state of spin ½ particles with Kink-like potential is studied under the massive Dirac equation. We obtain the scattering states in terms of the hypergeometric functions and calculate the reflection coefficient (R) and transmission coefficient (T)

    Pseudospin Symmetry of the Position-Dependent Mass Dirac Equation for the Hulthén Potential and Yukawa Tensor Interaction

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    This paper presents approximate analytical solutions of the Dirac equation for the Hulthén potential with position-dependent mass within the framework of pseudospin symmetry limit using the Nikiforov-Uvarov method. The results showed the relativistic energy spectrum and the corresponding un-normalized wave function expressed in terms of the Jacobi polynomials.Received: 30 September 2014; Revised: 29 December 2014: 31 December 201

    Solutions of the Klein-Gordon Equation with Equal Scalar and Vector Harmonic Oscillator plus Inverse Quadratic Potential

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    The solutions of the Klein-Gordon equation with equal scalar and vector harmonic oscillator plus inverse quadratic potential for S-waves have been presented using the Nikiforov-Uvarov method. The bound state energy eigenvalues and the corresponding un-normalized eigenfunctions are obtained in terms of the Laguerre polynomials

    Development and Sustainability of Eastern Mediterranean Region and South African National Food Composition Databases

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    Introduction: The World Health Organization’s (WHO)-Eastern Mediterranean Region Office (EMRO) aims to reduce the consumption of sugar, fat (saturated fatty acids, trans fatty acids) and salt; and decrease the risk of obesity and non-communicable diseases in the Eastern Mediterranean Region (EMR). To address this Quadram Institute Bioscience is working jointly with WHO-EMRO in providing training and capacity development to national experts, leading to standardized, harmonized, comprehensive, open access Food Composition Data (FCD) to underpin food and nutrition programs and policies in these low- and middle-income countries (LMIC). Materials and Methods: By identifying specific regional needs for FCD compilation, detailed training workshops were developed to enable the production of vital high-quality harmonised data in the EMR including: Iran, Iraq, Pakistan, Kuwait, Tunisia, Morocco, Sudan, Egypt, and Jordan. Training on standardized methodologies for food composition and dietary intake methods, biomarkers, analytical methods and FCD tools were provided by experts from UK, Serbia, Portugal and WHO-EMRO, via knowledge exchange workshops and short-term training exchange of researchers. Results: A total of 45 FCD expert compilers from 13 countries attended 2 workshops and 3 training exchanges. Knowledge transfer consisted of: value documentation; quality assessment; online food composition data tools; food classification and description of composite dishes; recipe calculation; yield and retention factors; and laboratory food analysis (vitamins A, B1, B2, C, D2, D3 and E, fatty acids, amino acids, minerals, fibre). FCD from 6 countries was standardized using the EuroFIR data template and Theasuri (standardised vocabularies). The final datasets from Iran, Iraq, Pakistan, Kuwait, Tunisia and Morocco were made available via FoodExplorer an innovative interface for FCD which allows users to search information from food composition data simultaneously across many countries. Discussion: The use of improved standardized methodologies for food composition and dietary intake will produce robust measurements that will reinforce dietary monitoring and policy in LMIC. The capacity building from this project has led to searchable national food composition data from LMIC being made available as open access form for the first time. WHO-EMRO, is funding further updates of FCD tables in Jordan, Lebanon, Oman, Sudan, Tunisia, Morocco, Pakistan, Iran, Egypt, and UAE, with the focus on identifying TFA, SFA, salt and sugar in addition to micronutrients.Project supported by Global Challenges Research Funds (UK) and Medical Research Council (MR/R019576/1), is grateful to WHO EMRO.info:eu-repo/semantics/publishedVersio

    Pigeonpea improvement: An amalgam of breeding and genomic research

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    In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research

    Burden of diarrhea in the Eastern Mediterranean Region, 1990�2015: Findings from the Global Burden of Disease 2015 study

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    Objectives: Diarrheal diseases (DD) are an important cause of disease burden, especially in children in low-income settings. DD can also impact children�s potential livelihood through growth faltering, cognitive impairment, and other sequelae. Methods: As part of the Global Burden of Disease study, we estimated DD burden, and the burden attributable to specific risk factors and etiologies, in the Eastern Mediterranean Region (EMR) between 1990 and 2015. We calculated disability-adjusted life-years (DALYs)�the sum of years of life lost and years lived with disability�for both sexes and all ages. Results: We estimate that over 103,692 diarrhea deaths occurred in the EMR in 2015 (95 uncertainty interval: 87,018�124,692), and the mortality rate was 16.0 deaths per 100,000 persons (95 UI: 13.4�19.2). The majority of these deaths occurred in children under 5 (63.3) (65,670 deaths, 95 UI: 53,640�79,486). DALYs per 100,000 ranged from 304 (95 UI 228�400) in Kuwait to 38,900 (95 UI 25,900�54,300) in Somalia. Conclusions: Our findings will guide evidence-based health policy decisions for interventions to achieve the ultimate goal of reducing the DD burden. © 2017, The Author(s)

    Burden of diarrhea in the Eastern Mediterranean Region, 1990�2015: Findings from the Global Burden of Disease 2015 study

    Get PDF
    Objectives: Diarrheal diseases (DD) are an important cause of disease burden, especially in children in low-income settings. DD can also impact children�s potential livelihood through growth faltering, cognitive impairment, and other sequelae. Methods: As part of the Global Burden of Disease study, we estimated DD burden, and the burden attributable to specific risk factors and etiologies, in the Eastern Mediterranean Region (EMR) between 1990 and 2015. We calculated disability-adjusted life-years (DALYs)�the sum of years of life lost and years lived with disability�for both sexes and all ages. Results: We estimate that over 103,692 diarrhea deaths occurred in the EMR in 2015 (95 uncertainty interval: 87,018�124,692), and the mortality rate was 16.0 deaths per 100,000 persons (95 UI: 13.4�19.2). The majority of these deaths occurred in children under 5 (63.3) (65,670 deaths, 95 UI: 53,640�79,486). DALYs per 100,000 ranged from 304 (95 UI 228�400) in Kuwait to 38,900 (95 UI 25,900�54,300) in Somalia. Conclusions: Our findings will guide evidence-based health policy decisions for interventions to achieve the ultimate goal of reducing the DD burden. © 2017, The Author(s)

    The Recognition of and Care Seeking Behaviour for Childhood Illness in Developing Countries: A Systematic Review

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    Background: Pneumonia, diarrhoea, and malaria are among the leading causes of death in children. These deaths are largely preventable if appropriate care is sought early. This review aimed to determine the percentage of caregivers in low- and middle-income countries (LMICs) with a child less than 5 years who were able to recognise illness in their child and subsequently sought care from different types of healthcare providers. Methods and Findings: We conducted a systematic literature review of studies that reported recognition of, and/or care seeking for episodes of diarrhoea, pneumonia or malaria in LMICs. The review is registered with PROSPERO (registration number: CRD42011001654). Ninety-one studies met the inclusion criteria. Eighteen studies reported data on caregiver recognition of disease and seventy-seven studies on care seeking. The median sensitivity of recognition of diarrhoea, malaria and pneumonia was low (36.0%, 37.4%, and 45.8%, respectively). A median of 73.0% of caregivers sought care outside the home. Care seeking from community health workers (median: 5.4% for diarrhoea, 4.2% for pneumonia, and 1.3% for malaria) and the use of oral rehydration therapy (median: 34%) was low. Conclusions: Given the importance of this topic to child survival programmes there are few published studies. Recognition of diarrhoea, malaria and pneumonia by caregivers is generally poor and represents a key factor to address in attempts to improve health care utilisation. In addition, considering that oral rehydration therapy has been widely recommended for over forty years, its use remains disappointingly low. Similarly, the reported levels of care seeking from community health workers in the included studies are low even though global action plans to address these illnesses promote community case management. Giving greater priority to research on care seeking could provide crucial evidence to inform child mortality programmes

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
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