Study of nonlinear convection in a sparsely packed porous medium using spectral analysis

Nonlinear study cellular convection in a sparsely packed fluid saturated porous medium is investigated, considering the Brinkman model, using the technique of spectral analysis. It is established how the Brinkman model with free-free boundaries generalizes the study of convection in a porous medium in the sense that it yields the results tending to those of viscous and Darcy flows respectively for very small and very large values of the permeability parameter �2. It also provides results for the transition zone (i.e. 102<�2<103). The cross-interaction of the linear modes caused by non-linear effects are considered through the modal Rayleigh number Rγ. The possibility of the existence of steady solution with two self-excited modes in certain regions is predicted. The similarities of present analysis with and advantages over that of the power integral technique are brought out. A detailed discussion of the heat transport, with the effect of permeability thereon, is made. The theoretical values of the Nusselt number are found to be in good agreement with experimental results. © 1983 Martinus Nijhoff Publishers

Identification of Beryllium Hydride Isotopomer Lines in Sunspot Umbral Spectra

A high resolution spectrum of FTS sunspot umbra of NSO/Kitt Peak was used to conduct a search for the molecular absorption lines due to BeH, BeD and BeT isotopomers. Analysis led to estimates of identification of the molecular lines of bands A - X (0,0), (1,1) and (2,2) for BeH, A - X (0,0), (1,1), (2,2) and (3,3) for BeD and of A - X (0,0), (1,1) and (2,2) for BeT. Among the identified lines, those which are well resolved were selected for measurements to calculate equivalent widths. The values of effective rotational temperature T were estimated for bands A - X(1,1) and (2,2) of BeH, A - X(1,1) of BeD and A - X(2,2) of BeT to be 4228K, 4057K, 3941K and 3243K respectively

Integrated energy planning: Part II. Examples of DEFENDUS scenarios

The first part of this paper presented an ab initio exposition of the development-focused end-use oriented service-directed (DEFENDUS) approach to energy planning. In this approach, the future demand for any source of energy is estimated on the basis of the energy services required and the efficiency with which these are provided. To meet this demand, the costs per unit of the available energy-supply/saving technologies are estimated and a least-cost mix of options identified. In this second part, some of the energy studies for which the DEFENDUS method has been used are described to demonstrate that its applicability is not confined to a particular region or source of energy. These studies include: electricity for five states of India, petroleum products for the country as a whole, biomass for the state of Karnataka, and a composite energy scenario for Karnataka involving integration of all the currently-used sources of energy. In every case, the energy usage pattern in the commencement year of the plan, i.e., the total energy usage disaggregated between the existing categories of users according to their end-uses, is obtained. Then, depending on the goals selected and the strategies that could be adopted to achieve them, growth rates for each category of users are used to estimate the number of users in future years. Improvement in the efficiency of end-use devices and/or substitution of energy sources are considered, to determine the possible reduction in the category-wise unit energy usage, and the corresponding energy requirement is estimated. The electricity plan for the state of Karnataka comprises future demand estimation as well as the comparative costs of various supply/saving options. For the other states, electricity demand has been estimated in various scenarios. In the oil scenarios for India, the focus is mainly on demand management through modal and carrier shifts, with emphasis on the middle distillates. The biomass strategy for Karnataka includes both demand- and supply-side measures. All these studies show that the DEFENDUS planning procedure is easily amenable to modification according to the particular case under consideration. Further, the integration of worksheets for individual sources of energy demonstrates that this method, though simple, is capable of dealing with composite energy planning. Above all, with the popularity of personal computers and spreadsheet packages, the DEFENDUS method facilitates the democratization of energy planning

Biomass energy technology transfer Strategies for large-scale diffusion in India

Bioenergy technologies (BETs) have potential to meet India's energy needs in a sustainable way, particularly for the vast rural areas. India is a pioneer in research and development of certain BETs such as biogas, improved cookstoves and small scale biomass gasifiers. However, developments on more advanced BETs have taken place outside India. Unless the process of technology transfer mechanisms at various levels is promoted and managed effectively, the potential benefits of these technologies to the society and environment at large may not be fully realized. This article attempts to understand the technology transfer and diffusion process for BETs, analyzes the barriers to their transfer and diffusion and finally suggests strategies for their large-scale diffusion in India

Astrophysical molecule CN : vibronic transition probability parameters

Abstract. Astrophysical applications are broadened by the emerging consensus on the vibration-electronic (vibronic) transition probability parameters such as Franck -Condon (FC) factors & r -centroids of some molecular species like CN , which could be useful in the identification of molecular lines and in the estimation of relative abundance of the species in various celestial bodies especially in the interstellar medium. Such important parameters, that is FC factors and r -centroids, have been computed by a reliable numerical integration procedure for the bands of E i systems of astrophysical molecule CN , using a suitable potential. For E − X system, the improved values of FC factors from the revised molecular constants are given along with the already reported values

The key project managers’ competences for different types of projects

This paper describes a quantitative research approach for identifying key project managers’ competences for different types of projects. By identifying the perceived most valuable project manager competences, as having the most potential for increased contribution to project management (PM) performance, practitioners and organizations can select their priorities when developing their PM practices. The 46 competences (technical, behavioural and contextual) provided by IPMA (International Project Management Association) were surveyed through an online questionnaire. Three dimensions to distinguish project types were used: application area, innovation and complexity. Completed questionnaires were received from 96 project managers from Portugal. The results showed that 13 key competences (20%) were common to the majority of the projects. Most of these are behavioural competences, such as: ethics, reliability, engagement, openness, and leadership. It was also observed a clear correlation between technical competences and project complexity

How do role conflict intensity and coping strategies affect the success of women entrepreneurs in Africa? Evidence from Ethiopia

Abstract: Please refer to full text to view abstrac

SARS-CoV-2 infection in acute pancreatitis increases disease severity and 30-day mortality: COVID PAN collaborative study

Objective: There is emerging evidence that the pancreas may be a target organ of SARS-CoV-2 infection. This aim of this study was to investigate the outcome of patients with acute pancreatitis (AP) and coexistent SARS-CoV-2 infection. Design: A prospective international multicentre cohort study including consecutive patients admitted with AP during the current pandemic was undertaken. Primary outcome measure was severity of AP. Secondary outcome measures were aetiology of AP, intensive care unit (ICU) admission, length of hospital stay, local complications, acute respiratory distress syndrome (ARDS), persistent organ failure and 30-day mortality. Multilevel logistic regression was used to compare the two groups. Results: 1777 patients with AP were included during the study period from 1 March to 23 July 2020. 149 patients (8.3%) had concomitant SARS-CoV-2 infection. Overall, SARS-CoV-2-positive patients were older male patients and more likely to develop severe AP and ARDS (p<0.001). Unadjusted analysis showed that SARS-CoV-2-positive patients with AP were more likely to require ICU admission (OR 5.21, p<0.001), local complications (OR 2.91, p<0.001), persistent organ failure (OR 7.32, p<0.001), prolonged hospital stay (OR 1.89, p<0.001) and a higher 30-day mortality (OR 6.56, p<0.001). Adjusted analysis showed length of stay (OR 1.32, p<0.001), persistent organ failure (OR 2.77, p<0.003) and 30-day mortality (OR 2.41, p<0.04) were significantly higher in SARS-CoV-2 co-infection. Conclusion: Patients with AP and coexistent SARS-CoV-2 infection are at increased risk of severe AP, worse clinical outcomes, prolonged length of hospital stay and high 30-day mortality

The ENIGMA-Epilepsy working group: Mapping disease from large data sets

Epilepsy is a common and serious neurological disorder, with many different constituent conditions characterized by their electro clinical, imaging, and genetic features. MRI has been fundamental in advancing our understanding of brain processes in the epilepsies. Smaller‐scale studies have identified many interesting imaging phenomena, with implications both for understanding pathophysiology and improving clinical care. Through the infrastructure and concepts now well‐established by the ENIGMA Consortium, ENIGMA‐Epilepsy was established to strengthen epilepsy neuroscience by greatly increasing sample sizes, leveraging ideas and methods established in other ENIGMA projects, and generating a body of collaborating scientists and clinicians to drive forward robust research. Here we review published, current, and future projects, that include structural MRI, diffusion tensor imaging (DTI), and resting state functional MRI (rsfMRI), and that employ advanced methods including structural covariance, and event‐based modeling analysis. We explore age of onset‐ and duration‐related features, as well as phenomena‐specific work focusing on particular epilepsy syndromes or phenotypes, multimodal analyses focused on understanding the biology of disease progression, and deep learning approaches. We encourage groups who may be interested in participating to make contact to further grow and develop ENIGMA‐Epilepsy

Trends in Prevalence of Advanced HIV Disease at Antiretroviral Therapy Enrollment - 10 Countries, 2004-2015.

Monitoring prevalence of advanced human immunodeficiency virus (HIV) disease (i.e., CD4+ T-cell count <200 cells/μL) among persons starting antiretroviral therapy (ART) is important to understand ART program outcomes, inform HIV prevention strategy, and forecast need for adjunctive therapies.*,†,§ To assess trends in prevalence of advanced disease at ART initiation in 10 high-burden countries during 2004-2015, records of 694,138 ART enrollees aged ≥15 years from 797 ART facilities were analyzed. Availability of national electronic medical record systems allowed up-to-date evaluation of trends in Haiti (2004-2015), Mozambique (2004-2014), and Namibia (2004-2012), where prevalence of advanced disease at ART initiation declined from 75% to 34% (p<0.001), 73% to 37% (p<0.001), and 80% to 41% (p<0.001), respectively. Significant declines in prevalence of advanced disease during 2004-2011 were observed in Nigeria, Swaziland, Uganda, Vietnam, and Zimbabwe. The encouraging declines in prevalence of advanced disease at ART enrollment are likely due to scale-up of testing and treatment services and ART-eligibility guidelines encouraging earlier ART initiation. However, in 2015, approximately a third of new ART patients still initiated ART with advanced HIV disease. To reduce prevalence of advanced disease at ART initiation, adoption of World Health Organization (WHO)-recommended "treat-all" guidelines and strategies to facilitate earlier HIV testing and treatment are needed to reduce HIV-related mortality and HIV incidence