Value Chain Analysis of Maize: The Case of Bako Tibe and Gobu Sayo Districts in Central West Ethiopia

This research attempted to generate useful information on maize value chain, which helps governmental institutions and NGOs to assess their activities and redesign their operations in Bako Tibe and Gobu Seyo districts. The research was done by identifying actors and mapping their interactions, evaluating incentives and cost structure, estimating determinants of maize marketed surplus. Data was collected from 199 randomly selected households, 53 maize traders, and 7 input suppliers. For data analysis, both descriptive and econometrics analysis of Tobit model were used. The result of the study showed that, maize average production, yield and marketed surplus were 36.95 quintal, 31.44 quintal per hectare and 18.23 quintal, respectively. Input suppliers, producers, traders and consumers were the main actors in the value chain. In the chain, no maize processors and exporters identified in the study areas. Through the value chain, the maximum value added was about ETB 49 per quintal and rural assemblers obtained the highest share of gross profit next to producers. The econometric model result showed that current price, district, fertilizer used, marketing costs, land allocation, distance to main market and non-farm income were significantly determining maize marketed surplus. Keywords: Mapping, Marketed surplus, Marketing Margin, Tobit model, Value chain

Assessment of Constraints and Opportunities of Tea Out-Growers in South West Ethiopia

This research attempted to generate useful information on tea out growers’ constraints and opportunities in tea production and marketing, which helps governmental institutions to assess their activities and redesign their operations. The research was done by interviewing tea out growers surrounding the two major tea plantations Wush Wush and Gumero in south west Ethiopia. Data was collected from 120 randomly selected households. Data was analyzed using descriptive statistics and Relative Severity Index to analyze constraints. The obtained result showed that, out-growers on average allocated 1.37 ha land to produce tea. They plucked on average 295 kg/ha export standard or 731 kg/ha local standard green tea leaves in one harvest in main season. Relative Severity index analysis revealed that out growers’ major constraints of tea production were high price and timely availability of inputs, shortage of inputs, high cost of production, need intensive plot management, lack of capital, no government intervention and extension service and lack of training. However, they have good opportunities in obtaining frequent income almost throughout the year, high cash income, low risk of animal damage and theft. Keywords: Tea out growers, Gumero, Wush Wush, Relative Severity Index, constraints DOI: 10.7176/DCS/11-6-02 Publication date:June 30th 202

In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate

Objective: To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Design: Prospective laboratory study. Setting: Tikur Anbessa Hospital, Addis Ababa, Ethiopia. Subjects: Clinical specimens from 443 hospital patients. Main outcome measures: Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis. Results: Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniue (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to l%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC I 0.01%. Twenty nine per cent of Acinetobacter, 28% of K. pneumoniae and Enterobacter species and 19-25% of Pseudomonas, Proteus and Providenciu species were only inhibited at high concentrations of CHG (2 0.1%). Conclusion: Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.East African Medical Journal, May 1999, 234-24

Chemical, physical, and microbiological characterstics of various sources of water in and around Addis Ababa

Abstract: Every month, from November 1996 to October 1997, water samples from 18 different sites were collected. The samples belong to the following categories: reservoirs that supply Addis Abeba's tap water (Lakes Gefersa and Legadadi) city taps, city swimming pools, Ambo Mineral Water, rain water, Akaki and Bulbula Rivers and Lake Aba Samuel. Four different physical variables (PH, Temperature, Total Dissolved Solids, and Conductivity) and concentration of 19 different cations, anions, and CO2 were determined. The results revealed no health risk except the high concentration of Cr3+, Cd2+, Fe3+, Pb2+, Mn4+ and Nitrate in Akaki and Bulbula Rivers samples. The water from these rivers is not consumed by city residents although they are used by rural communities to the east and southeast of Addis Abeba. Similarly, the two swimming pools included in this study had high TDS,HCO3- and fluoride content as well as slightly increased Cd2+, Pb2+ and Cu2+ levels. On the other hand, parasitological and bacteriological analyses revealed all sources were clean except Akaki, Bulbula and Aba Samuel. Infact these results suggest drinking waters of Addis Abeba are safe, while recreational waters of the city are acceptable for the purpose they serve. However, in view of polluted rivers flowing out of Addis Abeba and Lake Aba Samuel, methods of minimizing the health risks they pose are suggested. [Ethiop. J. Health Dev. 1999;13(3):239-246

Quadratic/linear rational spline interpolation

We describe the construction of an interpolating quadratic/linear rational spline S of smoothness class C 2 for a strictly convex (or strictly concave) function y on [a, b]. On uniform mesh x i = a + ih, i = 0,..., n, in the case of sufficiently smooth function y the expansions of S and its derivatives are obtained. They give the superconvergence of order h 4 for the first derivative, of order h 3 for the second derivative and of order h 2for the third derivative of S in certain points. Corresponding numerical examples are given

Linear/linear rational spline interpolation

For a strictly monotone function y on [a, b] we describe the construction of an interpolating linear/linear rational spline S of smoothness class C 1. We show that for the linear/linear rational splines we obtain ¦S(xi ) − y(xi )¦8 = O(h 4) on uniform mesh xi = a + ih, i = 0,…, n. We prove also the superconvergence of order h3 for the first derivative and of order h2 for the second derivative of S in certain points. Numerical examples support the obtained theoretical results. This work was supported by the Estonian Science Foundation grant 8313. First published online: 10 Feb 201

Identification of Rare Copy Number Variants Associated With Pulmonary Atresia With Ventricular Septal Defect

Copy number variants (CNVs) are major variations contributing to the gene heterogeneity of congenital heart diseases (CHD). pulmonary atresia with ventricular septal defect (PA-VSD) is a rare form of cyanotic CHD characterized by complex manifestations and the genetic determinants underlying PA-VSD are still largely unknown. We investigated rare CNVs in a recruited cohort of 100 unrelated patients with PA-VSD, PA-IVS, or TOF and a population-matched control cohort of 100 healthy children using whole-exome sequencing. Comparing rare CNVs in PA-VSD cases and that in PA-IVS or TOF positive controls, we observed twenty-two rare CNVs only in PA-VSD, five rare CNVs only in PA-VSD and TOF as well as thirteen rare CNVs only in PA-VSD and PA-IVS. Six of these CNVs were considered pathogenic or potentially pathogenic to PA-VSD: 16p11.2 del (PPP4C and TBX6), 5q35.3 del (FLT4), 5p13.1 del (RICTOR), 6p21.33 dup (TNXB), 7p15.2 del (HNRNPA2B1), and 19p13.3 dup (FGF22). The gene networks showed that four putative candidate genes for PA-VSD, PPP4C, FLT4, RICTOR, and FGF22 had strong interaction with well-known cardiac genes relevant to heart or blood vessel development. Meanwhile, the analysis of transcriptome array revealed that PPP4C and RICTOR were also significantly expressed in human embryonic heart. In conclusion, three rare novel CNVs were identified only in PA-VSD: 16p11.2 del (PPP4C), 5q35.3 del (FLT4) and 5p13.1 del (RICTOR), implicating novel candidate genes of interest for PA-VSD. Our study provided new insights into understanding for the pathogenesis of PA-VSD and helped elucidate critical genes for PA-VSD

Effects of nebulized sildenafil on lung histology, oxygen saturation and blood gas parameters in chronic asthmatic BALB/C mice that attack was developed with methacoline<br><br>

Amaç: Sildenafil erektil disfonksiyon tedavisinde kullanılan bir fosfodiesteraz 5 inhibitörüdür. Fosfodiesteraz 5'in inhibisyonu siklik guanozin monofosfat düzeylerinde artışa neden olur. Siklik guanozin monofosfat ile astım patofizyolojisinde anahtar bir düzenleyici rol oynayan siklik adenozin monofosfatın benzer etkileri, siklik guanozin monofosfat yolu ile astım tedavisi için yeni ilaç geliştirme olasılığını arttırmaktadır. Bu çalışmada literatürde ilk kez metakolinle atak provoke edilen kronik astımlı farelerde nebulize sildenafili kullanmayı ve nebulize sildenafilin akciğer histolojisi, oksijen saturasyonları ve kan gazı parametreleri üzerine etkilerini araştırmayı amaçladık. Metotlar: Otuzbeş BALB/c fare her bir grupta 7 fare olacak şekilde 5 gruba ayrıldı (Grup 1-5). Grup 1 (kontrol) dışındaki tüm farelerde 74 gün boyunca ovalbumin uygulamaları ile kronik astım modeli oluşturuldu. Grup 2'ye başka bir ilaç verilmedi. Grup 3, 4 ve 5'teki farelerde çalışmanın 75. gününde metakolin inhalasyonları ile astım atağı oluşturuldu. Sonrasında nebulize sildenafil (0.07 mg/ml), nebulize budesonid (0.25mg/ml) ve nebulize salin sırası ile Grup 3, 4 ve 5'e verildi. Metakolin inhalasyonları öncesi ve sonrasında ve tedavilerden 15 dakika sonra farelerin kalp hızları ve oksijen saturasyonları ölçüldü. Tedavilerden bir saat sonra fareler anestezi sonrası kalplerinden kan alınarak sakrifiye edildi ve kan örnekleri kan gazı analizi için kullanıldı. Grup 1 ve 2'deki fareler de yine aynı metodla sakrifiye edildi. Tüm farelerin akciğer histolojileri ışık ve elektron mikroskopi ile incelendi. Bulgular: Grup 1'in bazal membran, düz kas ve epitel kalınlıkları, mast ve goblet hücre sayıları Grup 2'ninkilerden anlamlı olarak düşüktü (sırası ile p=0.000, p=0.000, p=0.000, p=0.001, p=0.000). Grup 3'ün bazal membran kalınlığı ve mast hücre sayısı, Grup 5'in bazal membran kalınlığı ve mast hücre sayısından anlamlı şekilde düşüktü (sırası ile p=0.000, p=0.001). Grup 5'in düz kas kalınlığı, Grup 3'ünkinden anlamlı olarak düşüktü (p=0.000). Grup 4'ün bazal membran kalınlığı ve mast hücre sayısı Grup 5'inkilerden anlamlı olarak düşüktü (sırası ile p=0.000, p=0.000). Grup 4'ün düz kas kalınlığı, Grup 3'ünkinden anlamlı şekilde düşüktü (p=0.000). Oksijen saturasyonları, kalp hızları ve kan gazı parametreleri tedavilere göre gruplar arasında farklılık göstermemekte idi. Sonuç: Sonuçlarımız kronik astım modelinin başarı ile oluşturulduğunu göstermektedir. Nebulize sildenafil plaseboya göre bazal membran kalınlığında ve mast hücre sayısında anlamlı azalma sağlamıştır. Nebulize budesonid sadece düz kas kalınlığını nebulize sildenafile göre anlamlı olarak azaltmıştır bunun dışında tüm parametreler iki grup arasında benzerdir. Her üç tedavi de farelerin kalp hızı, oksijen saturasyonu ve kan gazı parametreleri arasında farklılık meydana getirmemiştir. Nebulize sildenafilin akut astım tedavisindeki etkinliğini göstermek için daha ileri çalışmalara ihtiyaç vardır. Objective: Sildenafil is a phosphodiesterase 5 inhibitor, which is used for the treatment of erectile dysfunction. The inhibition of phosphodiesterase 5 leads to an increase in cyclic guanosine monophosphate levels. Similar activities of cyclic guanosine monophosphate and cyclic adenosine monophosphate that plays a key regulatory role in the pathophysiology of asthma, raise the possibility of a new drug development for the treatment of asthma via cyclic guanosine monophosphate way. In this study, we aimed to use the nebulized sildenafil in chronic asthmatic mice in which an attack was provoked by methacoline and investigate the effects of sildenafil on lung histology, oxygen saturation and blood gas parameters for the first time in the literature. Methods: Thirty five BALB/c mice were divided into 5 groups each containing 7 mice (Group 1-5). In all mice, except Group 1 (control), the model of chronic asthma was established with ovalbumin administrations during 74 days. No other drug was given to Group 2. In Group 3, 4 and 5, asthma attack was developed by methacoline inhalations on day 75. After methacoline inhalationsæ nebulized sildenafil (0.07 mg/ml), nebulized budesonide (0.25mg/ml) and nebulized saline were given to Group 3, 4 and 5, respectively. Heart rates and oxygen saturations were measured before and after the methacoline inhalations and 15 minutes after the treatments. One hour after the treatments, mice were sacrificed after anesthesia by blood suction from the hearts and the blood samples were used for blood gas analysis. The mice in Group 1 and 2 were also sacrificed by the same method. Lung histologies of all mice were examined by light and electron microscopies. Results: Basement membrane, subepithelial smooth muscle layer, and epithelium thicknesses as well as numbers of mast cells and goblet cells were significantly lower in Group 1 than in Group 2 (respectively p=0.000, p=0.000, p=0.000, p=0.001, p=0.000). Basement membrane thickness and number of mast cells were significantly lower in Group 3 than in Group 5 (respectively p=0.000, p=0.001). Subepithelial smooth muscle layer thickness was significantly lower in Group 5 than in Group 3 (p=0.000). Basement membrane thickness and number of mast cells were significantly lower in Group 4 than in Group 5 (respectively p=0.000, p=0.000). Subepithelial smooth muscle layer thickness was significantly lower in Group 4 than in Group 3 (p=0.000). Oxygen saturations, heart rates, and blood gas parameters did not show difference between groups according to the treatments. Conclusion: Our results show that the model of chronic asthma was successfully established. Nebulized sildenafil decreased basement membrane thickness and number of mast cells significantly compared to placebo. Nebulized budesonide decreased only subepithelial smooth muscle layer thickness more than nebulized sildenafil, otherwise all the parameters were similar between the two groups. All the three therapies did not make difference in heart rates, oxygen saturations and blood gas parameters of mice. Further studies are needed to show the efficacy of nebulized sildenafil in the treatment of acute asthma