165 research outputs found
Socio-Economic Determinants of Smallholder Tree Plantation in Basona-Werana Woreda in the North Shoa of Amhara Regional State, Ethiopia
Tree growing by smallholders is an emerging livelihood strategy in Basona-Werana Woreda of the North Shoa Zone of Amhara Regional State. The objective of this study was to identify socio-economic determinants of the smallholder tree growing in the study area. Data were collected from the household survey, key informants and focus group discussions. The binary logistic regression model was employed to identify the socio-economic determinants of smallholder tree growing behavior. According to the study, about 55% of tree growers generated their livelihood income from tree planting whereas 72% of non-growers generated income from livestock. Family size of the household and age positively and significantly affected tree planting decisions at P < 0.10 and P < 0.01, respectively. Meanwhile, livestock ownership and distance to the market were negatively and significantly influenced the decision to tree planting at P < 0.01 and P < 0.05, correspondingly. Similarly, total household income positively and significantly (P < 0.01) affected tree planting decisions. This study concluded that the socio-economic circumstances of smallholder farmers must be taken into account in the formulation of initiatives and policies aimed at encouraging smallholders to grow trees in their farming systems to improve livelihood and sustainable agricultural production
Microbiological Safety of Street Vended Foods in Jigjiga City, Eastern Ethiopia
Background: Food safety problems are particularly becoming an increasingly serious threat to public health in developing countries. This study was conducted to assess microbiological safety of street vended foods from May to November, 2014 in Jigjiga City.Methods: A cross-sectional design was used to answer questions concerning the current status of food hygiene and sanitation practire of street food vending sites. Interview and observational assessments were used to collect socio-demographic data about street food venders. One hundred thirty-two samples of street foods were aseptically collected from four ‘kebeles’ of Jigjiga City. Both descriptive and analytical statistical methods were applied.Results: The majority of the street food vendors were women, 120(90.9%), with the average age group of 23-49 years, (42.85%), and 99(66.7%) them were illiterate. The study revealed that 95(72%) of the food samples had pathogenic bacterial contaminations. Three different bacterial species were isolated: E. coli 68(51.5%), S. aureus 85(64.4%) and 26(19.7%) Salmonella species. The highest incidence of S. aureus 23/33(69%) was seen in ‘Sambusa’; the highest incidence of E. coli 24/33(73.5%) was observed in ‘Pasta’, while the highest Salmonella incidence was observed in ‘Ades’.Conclusion: This study revealed that there is a reasonable gap on food safety knowledge among street food venders. The microbial profile was also higher compared to standards set by the World Health Organization. Due attention should be given by the government to improve knowledge about food safety and the quality standard of street foods sold in the City.Keywords: Microbiological safety, Street vended foods, Isolation, Jigjig
Photodegradation and Thermal Effects in Violet Phosphorus
Violet phosphorus (VP) has garnered attention for its appealing physical
properties and potential applications in optoelectronics. We present a
comprehensive investigation of the photo degradation and thermal effects of
exfoliated VP on SiO2 substrate. The degradation rate of VP was found to be
strongly influenced by the excitation wavelength and light exposure duration.
Light exposure to above bandgap light (> 532 nm) leads to significantly faster
degradation, attributed to interactions with reactive oxygen species (ROS)
generated by the laser. In contrast, lower energy excitation resulted in slower
degradation due to reduced ROS generation. Analysis of photoluminescence (PL)
spectra showed a gradual decline in the exciton population, signifying reduced
lifetime and alterations in formation and stability, ultimately affecting VP's
quantum efficiency. Power-dependent PL measurements at low temperature (4 K)
showed that the intensities of neutral excitons and trions linearly increased
with excitation power, while the energy difference between their peak energies
decreased, indicating changes in the exciton energy gap due to degradation at
higher laser power. At ambient temperature VP exhibited visible neutral exciton
(X0) and trion (T) peaks with higher X0 spectral weight, indicating reduced
thermal stability of T in VP crystals. Temperature dependent Raman showed the
presence of VP up to 673K and back down to room temperature; however, peak
intensities decreased and two new unknown peaks were observed indicating some
level of thermal degradation. Our results provide deeper understanding of VP's
degradation behavior and implications for optoelectronic applications.Comment: 22 pages, 6 figure
Creating and Using an Access Database to Enhance Subject Analysis and Obtain Faculty Input About the Journals Collection
Using Microsoft Access, Himmelfarb Health Sciences Library developed a database for all of its title-level journal holdings to assess and enhance its journal collection
Assessing the Practice of Birth Defect Registration at Addis Ababa Health Facilities
BACKGROUND፡ Birth defects are conditions that exist at birth and cause structural changes in one or more parts of the body. In order to plan proper management and design preventive activities of these conditions, accurate tracking, registration and analyses of the registered data are important. We assessed the practice of birth defect registration at Addis Ababa health facilities.METHODS: We retrospectively checked the existence of a separate birth defect registry book and assessed the delivery room registration book for completeness in registering birth defects. We also assessed the total number of birth defects registered during 2010-2015.RESULTS: We assessed the practice of birth defect registration at 37 delivery service providing health facilities in Addis Ababa, 20 public and 17 private institutions. Of the 37 health institutions assessed, 23 registered birth defects (3 of them used a separate birth defect registry books, and 20 used a regular registration book to register birth defects). The remaining 14 did not register any congenital anomaly. Of the institutions that do not register congenital anomalies, 10 are private and four are public.CONCLUSION: Only three delivery providing health facilities had a dedicated birth defect registry book which is close to ideal for a birth defect registration. There is a need for others to do the same until an electronic birth defect registration is established. This registration will serve as a resource for clinical governance and studies into quality of life, quality of care, etiology and prevention
Conducting a Journal Assessment Project Using Microsoft Access to Obtain Faculty Input and Promote the Creation of a Cost-Effective Journal Collection
Himmelfarb Health Sciences Library created a database using Microsoft Access to execute a value assessment project of its online and print journal collection. This poster presentation summarizes the process of creating a cost-effective journal collection
Sulfur Vacancy Related Optical Transitions in Graded Alloys of MoxW1-xS2 Monolayers
Engineering the electronic bandgap is of utmost importance in diverse domains
ranging from information processing and communication technology to sensing and
renewable energy applications. Transition metal dichalcogenides (TMDCs) provide
an ideal platform for achieving this goal through techniques including
alloying, doping, and creating in-plane or out-of-plane heterostructures. Here,
we report on the synthesis and characterization of atomically controlled
two-dimensional graded alloy of MoxW1-xS2, wherein the center region is Mo rich
and gradually transitions towards a higher concentration of W atoms at the
edges. This unique alloy structure leads to a continuously tunable bandgap,
ranging from 1.85 eV in the center to 1.95 eV at the edges consistent with the
larger band gap of WS2 relative to MoS2. Aberration-corrected high-angle
annular dark-field scanning transmission electron microscopy showed the
presence of sulfur monovacancy, VS, whose concentration varied across the
graded MoxW1-xS2 layer as a function of Mo content with the highest value in
the Mo rich center region. Optical spectroscopy measurements supported by ab
initio calculations reveal a doublet electronic state of VS, which was split
due to the spin-orbit interaction, with energy levels close to the conduction
band or deep in the band gap depending on whether the vacancy is surrounded by
W atoms or Mo atoms. This unique electronic configuration of VS in the alloy
gave rise to four spin-allowed optical transitions between the VS levels and
the valence bands. Our work highlights the potential of simultaneous defect and
optical engineering of novel devices based on these 2D monolayers.Comment: 65 pages, 7 figures in main text. 21 figures in supplemental dat
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