Spatial and temporal variation in crop diversity in agroforestry homegardens of southern Ethiopia

A key assumption in many homegarden studies is that homegardens are ecologically and socio-economically sustainable due to their species diversity. The precise relation between diversity and sustainability is still heavily debated, however. A basic question is how diversity in homegardens can best be characterized in view of the various dimensions of species diversity and their variation in time and space. This paper assesses different types of species diversity in the homegardens of Sidama region of southern Ethiopia. In a survey of crop species in 144 homegardens a total of 78 cultivated crop species (excluding trees) belonging to 10 functional groups were recorded; there were on average 16 crop species and 8 functional groups per farm. Within homegardens, plots differ in species composition and crop diversity. Four types of homegarden systems are distinguished differing in both type and area-share of dominant species, relative orientation at subsistence or cash production and overall crop diversity. The gradual replacement of enset by maize and of coffee by more financially attractive cash crops khat and pineapple causes a decrease in overall crop diversity. Our data demonstrate that it is incorrect to consider homegardens as generic systems with a uniform distribution of species diversity: important within and between homegarden variation exists. Ecological and socio-economic sustainability is not just related to species diversity per se, but rather to more specific features such as presence of keystone species and diversity in functional species groups. Socio-economic sustainability in terms of adjustment to socio-economic change implies dynamics in species diversit

Ethiopia\u27s Sovereign Right of Access to the Sea under International Law

Since Eritrea’s secession from Ethiopia there has been continuous opposition by intellectuals and the opposition to the government’s policy of making Ethiopia a landlocked country. Some totally reject the secession, while others accept the independence as a fait accompli and voice concern over the lack of an outlet to the sea, and still others acknowledge the right of self-determination and secession of Eritrea but denounce the inconsistency of the application of the Transitional Charter regarding the Red Sea Afar and the Algiers Agreement for denying Ethiopia its legitimate right to access to the sea and allege that the government is acting against the paramount national interest of the country

Biochemistry of 1, 2-Dehydro-N-Acetyldopamine Derivatives

Dehydrodopa/dopamine derivatives form an important group of biomolecules participating in sclerotization of all arthropod cuticles, gluing and cementing mussels and related organisms to solid surfaces, and defense reactions of countless marine and invertebrate organisms. Yet very little information is available on the biochemistry of these highly reactive and unstable molecules. To understand their physiological role, I conducted a thorough biochemical study on three representative compounds that cover the entire plethora of dehydrodopa/dopamine derivatives. Employing diode array UV-visible spectroscopy, HPLC, liquid chromatography-mass spectrometry, and electrospray ionization tandem mass spectrometry, I investigated the oxidation chemistry of 1,2-dehydro-N-acetyldopamine (dehydro NADA), 1,2-dehydro-N-acetyldopa and 1,2-dehydro-N-acetyldopa methyl ester. Tyrosinase converted dehydro NADA to a reactive quinone methide that formed oligomeric products with the parent compound. The sister enzyme laccase, produced semiquinone radicals that exhibited a novel coupling reaction producing just dimers. Nonenzymatic oxidation of dehydro NADA also produced semiquinone radicals that formed oligomeric products. Moreover, nonenzymatic oxidation resulted in the production of superoxide anions that could function in defense reactions. The nonenzymatic oxidation studies on dehydro NADA at mild alkaline conditions revealed the mechanisms of defense reactions and tunic formation in a vast array of tunicates. Oxidative transformations of 1,2-dehydro-N-acetyldopa indicated a new route for the biosynthesis of a vast array of bioactive marine molecules possessing dihydroxycoumarin skeleton. In addition, it revealed new transformations of coumarins to oligomeric products via highly reactive quinone methide intermediates. Biochemical studies on 1,2-dehydro-N-acetyldopa methyl ester revealed a new Diels Alder type condensation of its quinone with the parent compound. This reaction shed light on the mode of gluing of mussels and other bivalves to solid surfaces as well as the hardening reactions occurring in their periostracum. I also examined the oxidation chemistry of dehydro NADA with a model nucleophile, N-acetylcysteine and discovered yet another new addition reaction of dehydro NADA that has tremendous biological significance. Finally, I investigated the mechanism of dehydro NADA binding to insect cuticle using labeled compounds and established that they could uniquely produce ketocatecholic compound, arterenone upon hydrolysis. The biochemical significances of all these new reactions are discussed in the dissertation

Seroepidemiology of hepatitis B virus in Addis Ababa Ethiopia: transmission patterns and vaccine control

A community-based seroepidemiological survey of Addis Ababa, Ethiopia was conducted in 1994 to inform on the transmission dynamics and control of hepatitis B virus (HBV) infection. Venous blood from 4736 individuals under 50 years of age from 1262 households, selected using stratified cluster-sampling, was screened for HBV markers using commercial ELISAs. HBsAg prevalence was 7% (95% CI 6–8), higher in males (9%; 7–10) than females (5%; 4–6). HBeAg prevalence in HBsAg positives was 23% (18–29), and less than 1% of women of childbearing age were HBeAg positive. Overall HBV seroprevalence (any marker), rose steadily with age to over 70% in 40–49 year olds, indicating significant childhood and adult transmission. Estimated instantaneous incidence was 3–4/100 susceptibles/year, higher in males than females in 0–4 year olds, and peaking in early childhood and young adults. The age at which 50% had evidence of infection was around 20 years, and the herd immunity threshold is approximated at 63–77%. Addis Ababa is of intermediate-high HBV endemicity, with negligible perinatal transmission. Our main findings are the identification of a significant difference between males and females in the age-acquisition of HBV infection, and marked differences between age groups in HBV incidence rates. These results should target future research studies of underlying risk factors. Furthermore, we generate a crude estimate of the level of coverage of HBV vaccine that would be required to eliminate the virus from the study population

Isolation and antimicrobial susceptibility pattern of Staphylococcus aureus in patients with surgical site infection at Debre Markos Referral Hospital, Amhara Region, Ethiopia

BACKGROUND: Staphylococcus aureus, especially Methicillin Resistant Staphylococcus Aureus (MRSA) is a major health problem recognized as the most important nosocomial pathogen, often causing postoperative wound infections. Antibiotic resistance by MRSA has grown to be common, and resistance to almost all antibiotics has been found among these strains. The aim of this study was to determine the prevalence, antimicrobial susceptibility patterns and associated risk factors of S. aureus in patients with surgical site infections in an Ethiopian hospital. METHODS: A cross-sectional study was conducted from December 1, 2011 to March 30, 2012 among patients with surgical site infections at Debre Markos Referral Hospital, Debre Markos, Ethiopia. All wound swabs obtained from patients with surgical site infections during the study period were cultured on mannitol salt agar media which is selective for S. aureus. Isolated strains of S. aureus were tested for antibiotic susceptibility patterns using standard disc diffusion technique, and interpretation of resistance was done based on Clinical and Laboratory Standard Institute criteria. Univariate and multivariable analyses were used to assess the risk factors. RESULTS: Of the 184 surgical patients who had developed surgical site infection, S. aureus was isolated from 73 (39.7%) cases. Out of the 73 isolates of S. aureus, 36 (49.7%) were MRSA. Among the study participants, prevalence of MRSA was found to be 19.6%. The clinical isolates showed >80% level of resistance to ampicillin, amoxicillin, penicillin G, erythromycin, gentamicin and cotrimoxazole whereas <50% level of resistance was observed against clindamycin, oxacillin, tetracycline and vancomycin. MRSA strains showed resistance ranging from 5.6% (vancomycin) to 100% (cotrimoxazole). Of the following risk factors: sex, age, pus consistency, duration of operation, type of surgery, ward and hospital stay, laparotomy type of surgery was identified as a risk factor for infection by S. aureus. CONCLUSION: The prevalence of S. aureus and/or MRSA infection in surgical and gynaecology & obstetrics wards of Debre Markos Referral Hospital was found to be high. The majority of isolates were highly resistant to major antimicrobial agents

Fertility Desire and Contraceptive Utilization among People Living With HIV/AIDS on ART in Hosanna Town, Southern Ethiopia

HIV positive individuals may or may not have intention to have children. They could also have different degrees of utilization and demand for contraception. The desire of HIV infected persons to have children in the future has implication for the transmission of HIV to sexual partners or newborns. The study was designed to assess the fertility desire and contraceptive utilization among PLWHAs on ART in Hossana town. institutional based cross sectional study supplemented by in-depth  interview was conducted from January to March 2010 on total sample of 321 who were on ART. Women 18-49 years and men 18-59 years were included. Data was entered by using EPI info 2000 then exported and  analyzed by SPSS 17.0. Total of 117 (36.45%) of respondents were   desiring children. Respondents with no children (AOR 60.89, 95% CI  8.02-462.05), those who intended to use family planning in the future (AOR 4.35, 95% CI 1.61-11.73) were more likely to desire children. 102(31.8%) were using family planning. Being married (AOR 7.83, 95% CI 1.08-56.79), having three or more children (AOR 4.54, 95% CI  1.12-18.48), and having knowledge on mother to child transmission (AOR 4.29, 95% CI 1.98-9.26) plan to have children in the future (AOR 0.29, 95% CI 0.1-0.82) were significantly associated with family planning. A highproportion of HIV positive individuals desired children. A better and   evidence based understanding of fertility intentions and demand for contraception was needed to promote and protect women and men living  with HIV/AIDs to make informed decisions about reproduction and to have access to appropriate sexual reproductive health services

A critique of current methods in nematode taxonomy

Morphology based nematode taxonomy and biodiversity studies have historically challenged most biologists. In the past few decades, there have been efforts to integrate molecular methods and digital 3D image-capturing technology in nematode taxonomy, the former to enhance the accuracy of identification of such a taxonomically challenging group and the latter to communicate morphological data. While the employment of these two methods is growing in recent taxonomic, biodiversity andbiogeographic studies, a movement to abandon traditional phenotypic identification methods altogether has emerged. Proponents try to justify this trend by citing the challenging gap between the high estimated number of undescribed species and the limited ability of traditional taxonomy to accomplish the task of documenting such diversity. Here we present a review of the various techniques used in the taxonomy of free-living and plant parasitic nematodes and critique those methods in the context of recent developments and trends including their implications in nematode taxonomy, biodiversity and biogeography.Key words: Species delimitation, taxonomic methods, genetic and molecular methods, traditional taxonomy, nematode biodiversity

A retrospective study on prevalence and antimicrobial susceptibility patterns of bacterial isolates from urinary tract infections in Tikur Anbessa Specialized Teaching Hospital Addis Ababa, Ethiopia, 2011

Introduction: Urinary tract infection is an inflammation of the urinary tract that occurs when micro organisms, usually bacteria from digestive tract or  vagina cling to the opening of the urethra and begin to multiply. An estimated 150 million urinary tract infections occur annually worldwide. Indiscriminate use of antibiotics has resulted in the emergence of drug resistant pathogens now.Objective: To determine the prevalence and drug susceptibility patterns of bacterial pathogens involved in urinary tract infections within the last three years, January 1st 2008 to December 30th 2010 in Tikur Anbesa Specialized Teaching Hospital of Addis Ababa, Ethiopia.Method: An institution-based retrospective cross sectional population survey was conducted in the clinical laboratory for diagnosis of patients visiting Tikur Anbessa Specialized Teaching Hospital. Collected secondary data were entered and analyzed using SPSS version 17 computer software package. Percentages and ratios were calculated in tables. P-value was used to see statistical significance (p<0.05).Results: Out of 3254 recorded patient’s data 3182 results were taken and analyzed. The overall prevalence of urinary tract infection was 23.32 % and the highest prevalence was obtained among age groups 21-30 years (27.16%). The bacterial pathogens isolated were predominantly, Escherchia coli: 361 (44.62%), followed by Klebsella Spp: 136 (16.81%), Coaggulase negative Staphylococci Spp: 49 (6.06%) and Entrococci Spp: 41 (5.06%). The invitro drug sensitivity testing showed that both gram negative and gram-positive organisms were extremely resistant to Ampiciline: (83.93%), Amoxicillin: (78.87%) and Tetracycline: (77.75%).Conclusion: the prevalence of urinary tract infection was high, and the drug resistance rate was extremely high. For this reason, it is necessary to minimize the rate of urinary tract infections, and to constantly monitor susceptibility patterns of specific pathogens to commonly used antimicrobial agents before antibiotic therapy initiation

Immunological Markers and Hematological Parameters among Newly Diagnosed Tuberculosis Patients at Jimma University Specialized Hospital

Background: Tuberculosis (TB) is a cause of 1.2-1.5 million deaths worldwide, including deaths from TB among HIV positive people. Determining the extent of immune cells belonging to cell mediated immunity and haematological parameters is critical to maximize the potential benefit of anti-tubercular treatment and case management.Meterials and Methods: Comparative cross sectional study was conducted to determine the white blood cell (WBC) count, CD4, CD8, haemoglobin (Hgb), red blood cell (RBC) count, mean corpuscular haemoglobin (MCHC), mean corpuscular volume (MCV) between newly diagnosed TB patients and apparently healthy controls (HCs).Results: From consecutively enrolled 108 TB patients, pulmonary TB (PTB) accounted for 48(44.4%), TB lymphadenitis accounted for 48(44.4%), and disseminated/miliary TB accounted for 12(11.1%). Analysis of variance revealed that mean + SD of CD4 count of male TB patients (650 + 224cells/μl) was significantly lower than male control group (883 + 256 cells/μl) (p= 0.001). In a similar manner, the mean CD4 count of female TB patients (793 + 332cells/μl) was lower than female control group (975 + 300 cells/μl) (p=0.001). There was no statistically significant difference in CD8 counts between cases and controls for both genders. Forty (37.0%) TB patients had developed anaemia of whom 22(55%) were among PTB, 13(32.5%) from tuberculous lymphadenitis and 5(20%) from disseminated TB. Morphologically, from all anaemia among TB patients, normocytic normochromic anaemia accounted for 15(37.5%) followed by normocytic hypochromic anaemia 13(30.4%).Conclusion: CD4 lymphopenia was significant among TB patients. Granulocyte count was increased. Mild anaemia was found major haematological abnormality among newly diagnosed TB patients.Keywords: Tuberculosis, CD4 count, CD8 count, anaemia, haemoglobi

Bacterial Profile and Antimicrobial Susceptibility Pattern of Isolates Among Burn Patients at Yekatit 12 Hospital Burn Center, Addis Ababa, Ethiopia

Background: Infection is a common cause of morbidity and mortality in burn patients. Clinical diagnosis of bacteremia and/or sepsis in burn patients is difficult for a number of reasons. It could be symptomatic and/or asymptomatic as a result of immune deficiency secondary to thermal injury.Methods: A cross sectional study was conducted at Yekatit 12 Hospital Burn Center. Blood specimen and wound swab were collected from burn patients and were cultured by conventional method. Sensitivity/susceptibility pattern of the isolates was determined by disc diffusion method. Some of the risk factors of bacteremia like prior antibiotic use and total body surface area burn were also determined.Results: Fifty patients were enrolled in the study of whom 21(42%) were found bacteremic. Five different bacteria were isolated from blood specimen. Coagulase negative Staphylococci, 9(42.8%), S. aureus, 8(38.2%), Bacillus spps, 2(9.52%), K. pneumoniae, 1(4.8%), and P. aeruginosa, 1(4.8%), were frequent isolates. From wound swab, S. aureus, (34.04%), and P. aeruginosa, (31.8%), were predominant. Antimicrobial resistance was observed for Ampicillin, (77.4%), Doxycycline, (74.0), Nalidixic acid, (70.5%), Penicillin G, (68.2%), and tetracycline, (67.5%). Total body surface area of burn ≥ 15% was found as a risk factor for bacteremia.Conclusion: Bacteremia was detected at a rate of 42% among burn patients. Frequent isolates were S. aureus, (34.04%), and P. aeruginosa, (31.8%). About 82.16% of the isolates showed multiple resistances. In light of our findings, regular antibiotic resistance test has to be done for each patient in order to select an appropriate antimicrobial agent.Keywords: Bacteraemia, Burn, Sepsis, Thermal injur