Optimal Design of a Standalone Photovoltaic Power Supply System for Air Conditioning Application at Samara University as an Alternative to Diesel Generator Source

The aim of this paper is to optimally design a stand alone photovoltaic power supply system for air conditioning application at Samara University to be used as an alternative to diesel generator supply. Samara University is established in samara town, Afar region and has an average daily radiation of 6.10kwh/m2, sun shine duration of about 10 hours. This  condition invites the use of photovoltaic system as an alternative primary energy source to replace the existing diesel generator supply system. Therefore in order to use this energy source for air conditioning application, the cooling load of the building, 628 tons, is estimated using Newton’s thumb rule. The evaporative air conditioning system which is sometimes called desert cooler is selected to condition the estimated cooling load of the dwelling room. The sizing method (numerical method and HOMER software tools) is complementarily used to design a standalone photovoltaic power supply system. Finally, the metric value of the present worth is US $ 3,302,066 and its simple payback is 6.6 years, and this foreseen that the attractiveness of photovoltaic power system as one of renewable energy to be used as an alternative to diesel generator in the near future

Men’s Knowledge and Spousal Communication about Modern Family Planning Methods in Ethiopia

This study attempted to determine knowledge, approval and communication about family planning methods among married men in Ethiopia. A cross-sectional study was conducted among a representative sample of 738 married males in Amhara Region. All 738 (100%) of the respondents had heard of family planning. About 558 (75.6%) mentioned the importance of using contraceptives for birth spacing and 457 (61.9%) to limit birth. Four hundred and forty-five (60.3%) of participants had ever discussed family planning with their wives. Thirty-three (33.0%) of the respondents reported that they were the sole decision makers in their families. About 597 (80.9%) approved the use of contraceptives. However, some participants did not discuss and approve family planning with their partner. This recalled an intensive effort has been taken by the concerned body to reach the country’s targeted family planning coverage by involving men in reproductive health endeavor to enhance the discussion and agreement about family planning usage

Study on knowledge, attitude and dog ownership patterns related to rabies prevention and control in Addis Ababa, Ethiopia

The study was conducted from May 2003 to August 2003 in Addis Ababa with the objective of understanding the distribution of stray and owned dogs, dog ownership patterns and attitudes of people towards rabies and its prevention and control methods. A total of 2390 households were selected from 6 Sub Cities of Addis Ababa using stratified random sampling and were interviewed using structured questionnaires. From the total households interviewed, 969 (40.5%) of them were known to own one or more dogs, and the total number of owned dogs was estimated to be 225,078. Male dogs make up 1042 (78.4%) of the total owned dogs. Almost half of all the dogs 463 (47.8%) were tied only for some time during the day whereas 320 (33.1%) of the dogs were not tied at all and freely move from place to place and contribute to high dog bites in human beings and for the widespread occurrence of canine rabies in Addis Ababa. Six hundred fifty five (67.6%) of the interviewed households who owned dogs had a well fenced house. Most of the owned dogs 856 (88.4%) get their food from their owners and only 321 (33.3%) of the owners reported that they let their dogs to be vaccinated while the majority of the owners 644 (66.5%) do not let their dogs vaccinated regularly. A significant proportion of the interviewed households 2,323 (97.2%), (P < 0.05) indicated that they have the knowledge that dogs, cats and other animals can transmit rabies to humans and 1,752 (73.4%) of the households replied that rabies can be transmitted through bite, scratch and lick to open wounds. Analysis of the list of 2400 post exposure human antirabies treatments recorded at the EHNRI Zoonoses Laboratory from February 2002 to October 2003 showed that the most common animals involved in biting people were dogs. A total of 2198 (91.6%) people were bitten by dogs during the same period and most of them, 2053 (85.5%) were bitten on their hands and legs. All the above data indicated the need for a strong and coordinated rabies control activities to be conducted in the city

Consumer drivers and barriers of WASH products use in rural Ethiopia

In Ethiopia, the coverage of basic WASH facilities is very low. In response, government of Ethiopia and its development partners have been using sanitation marketing to promote and sell WASH products. Qualitative in-depth interview with households, supply chain actors, and stakeholders were conducted in four regions of Ethiopia to learn about current product use behaviours. The result showed presence of any latrine was related to greater awareness about importance to health. Financial constraints, unavailability of construction materials were major barriers to possession of latrines. Word of mouth was the dominant source of information on WASH products, with health extension workers being a respected source. The major challenges of supply chain actors at district level were finance, inadequate working space, and lack of business development skills. Lack of regular WASH products supply system at community level and lack of profound awareness about health benefit were the priority constrains to access latrines

Acute respiratory muscle unloading improves time-to-exhaustion during moderate- and heavy-intensity cycling in obese adolescent males

Obesity significantly impairs breathing during exercise. The aim was to determine, in male obese adolescents (OB), the effects of acute respiratory muscle unloading, obtained by switching the inspired gas from ambient air (AIR) to a normoxic helium + oxygen gas mixture (HeO2) (AIR \u2192 HeO2) during moderate [below gas exchange threshold (GET)] and heavy [above GET] constant work rate cycling. Ten OB [age 16.0 \ub1 2.0\ua0years (mean \ub1 SD); body mass index (BMI) 38.9 \ub1 6.1\ua0kg/m2] and ten normal-weight age-matched controls (CTRL) inspired AIR for the entire exercise task, or underwent AIR \u2192 HeO2 when they were approaching volitional exhaustion. In OB time to exhaustion (TTE) significantly increased in AIR \u2192 HeO2 vs. AIR during moderate [1524 \ub1 480\ua0s vs. 1308 \ub1 408 (P = 0.024)] and during heavy [570 \ub1 306\ua0s vs. 408 \ub1 150 (P = 0.0154)] exercise. During moderate exercise all CTRL completed the 40-min task. During heavy exercise no significant differences were observed in CTRL for TTE (582 \ub1 348\ua0s [AIR \u2192 HeO2] vs. 588 \ub1 252 [AIR]). In OB, but not in CTRL, acute unloading of respiratory muscles increased TTE during both moderate- and heavy-exercise. In OB, but not in CTRL, respiratory factors limit exercise tolerance during both moderate and heavy exercise

A Compton-Suppressed Phoswich Detector for Gamma Spectroscopy

A phoswich detector with two scintillation layers has been designed and assembled at Oregon State University. This detector is able to identify and reject Compton events and ultimately reduce the Compton continuum in gamma energy spectra. In this detector, CsI(Tl) crystal is used to primarily detect photoelectric events. The CsI(Tl) crystal is partially surrounded by a BGO crystal layer to capture and identify Compton-scattered photons. Both crystals are optically coupled to a single photomultiplier tube. A real-time, FPGA-based digital pulse shape analysis was developed to discriminate and reject Compton-induced pulses from the CsI(Tl) crystal. All the digital pulse processing functions including pulse shape discrimination analysis, pile-up rejection and energy measurement were implemented in an on-board FPGA device. In this paper, the results of recent measurements using radioactive lab sources will be presented and discussed.Keywords: Phoswich Detectors, Digital Pulse-Shape Discrimination, Compton Suppression, Gamma Spectroscopy, Scintillator

A Phoswich Detector with Compton Suppression Capability for Radioxenon Measurements

A phoswich detector with Compton suppression capability has been developed and tested for measuring xenon radioisotopes via a beta-gamma coincidence measurement technique. The phoswich detector has been designed with three scintillation layers. Beta-gamma coincidence events from radioxenon isotopes are identified when a coincidence energy absorption is detected in the first (BC-400) and second (CsI(Tl) crystal) scintillation layers. To identify and reject scattered photons from the CsI(Tl) crystal, the crystal is surrounded by a BGO scintillation layer. Our measurements show that the Compton suppression mechanism reduces the Compton continuum from 662 keV photons by 20%-50% in the low-energy region of spectrum. Our beta-gamma coincidence measurements with ¹³⁵Xe and ¹³³Xe radioisotopes show energy resolutions (FWHM) of 13%, 46% and 24% for 250 keV, 30keV and 80 keV gamma-ray peaks, respectively. In this paper, the detector design, assembly steps, digital pulse shape discrimination technique, and our recent measurements with radioactive lab sources and xenon radioisotopes are discussed.This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by IEEE-Institute of Electrical and Electronics Engineers and can be found at: http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=23. (c) 2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.Keywords: Pulse shape discrimination, Phoswich detector, Compton suppression, Radioxenon measuremen

Readmission and death after an acute heart failure event: predictors and outcomes in sub-saharan africa: results from the thesus-hf registry

Aims: Contrary to elderly patients with ischaemic-related acute heart failure (AHF) typically enrolled in North American and European registries, patients enrolled in the sub-Saharan Africa Survey of Heart Failure (THESUS-HF) were middle-aged with AHF due primarily to non-ischaemic causes.We sought to describe factors prognostic of re-admission and death in this developing population. Methods and results: Prognostic models were developed from data collected on 1006 patients enrolled in THESUS-HF, a prospective registry of AHF patients in 12 hospitals in nine sub-Saharan African countries, mostly in Nigeria, Uganda, and South Africa. The main predictors of 60-day re-admission or death in a model excluding the geographic region were a history of malignancy and severe lung disease, admission systolic blood pressure, heart rate and signs of congestion (rales), kidney function (BUN), and echocardiographic ejection fraction. In a model including region, the Southern region had a higher risk. Age and admission sodium levels were not prognostic. Predictors of 180-day mortality included malignancy, severe lung disease, smoking history, systolic blood pressure, heart rate, and symptoms and signs of congestion (orthopnoea, peripheral oedema and rales) at admission, kidney dysfunction (BUN), anaemia, and HIV positivity. Discrimination was low for all models, similar to models for European and North American patients, suggesting that the main factors contributing to adverse outcomes are still unknown. Conclusion: Despite the differences in age and disease characteristics, the main predictors for 6 months mortality and combined 60 days re-admission and death are largely similar in sub-Saharan Africa as in the rest of the world, with some exceptions such as the association of the HIV status with mortality

Wheat rust epidemics damage Ethiopian wheat production: A decade of field disease surveillance reveals national-scale trends in past outbreaks.

Wheat rusts are the key biological constraint to wheat production in Ethiopia-one of Africa's largest wheat producing countries. The fungal diseases cause economic losses and threaten livelihoods of smallholder farmers. While it is known that wheat rust epidemics have occurred in Ethiopia, to date no systematic long-term analysis of past outbreaks has been available. We present results from one of the most comprehensive surveillance campaigns of wheat rusts in Africa. More than 13,000 fields have been surveyed during the last 13 years. Using a combination of spatial data-analysis and visualization, statistical tools, and empirical modelling, we identify trends in the distribution of wheat stem rust (Sr), stripe rust (Yr) and leaf rust (Lr). Results show very high infection levels (mean incidence for Yr: 44%; Sr: 34%; Lr: 18%). These recurrent rust outbreaks lead to substantial economic losses, which we estimate to be of the order of 10s of millions of US-D annually. On the widely adopted wheat variety, Digalu, there is a marked increase in disease prevalence following the incursion of new rust races into Ethiopia, which indicates a pronounced boom-and-bust cycle of major gene resistance. Using spatial analyses, we identify hotspots of disease risk for all three rusts, show a linear correlation between altitude and disease prevalence, and find a pronounced north-south trend in stem rust prevalence. Temporal analyses show a sigmoidal increase in disease levels during the wheat season and strong inter-annual variations. While a simple logistic curve performs satisfactorily in predicting stem rust in some years, it cannot account for the complex outbreak patterns in other years and fails to predict the occurrence of stripe and leaf rust. The empirical insights into wheat rust epidemiology in Ethiopia presented here provide a basis for improving future surveillance and to inform the development of mechanistic models to predict disease spread