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1.
Sci Total Environ ; 731: 139094, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32417478

RESUMO

Wheat production is expected to be challenged by future climate change. However, it is unclear how wheat grown in diverse agroecologies will respond to climate change and adaptation management strategies. A geospatial simulation study was conducted to understand the impacts of climate change and adaptation management strategies on wheat (Triticum aestivum L.) production in Ethiopia. Simulation results showed that the average long-term baseline (1980-2005) wheat yield ranged from 1593 to 3356 kg/ha. This wheat yield range is within the national average (2100-2700 kg/ha) for this decade. In regions with cooler temperatures (<21 °C), mid-century temperatures and elevated CO2, along with increased N fertilizer slightly improved attainable yield levels above 3000 kg/ha. Whereas, in regions with heat and drought conditions wheat yield declined regardless the increase of N or CO2 levels. Wheat yield increased at a diminishing rate with increase in N fertilizer rate. However, N fertilizer did not increase yields under low rainfall conditions. Two to five irrigation per season contributed to yield improvement for low rainfall locations, while yield did not substantially improve for locations receiving adequate seasonal rainfall. Therefore, based on this study, improved N fertilizer application in combination with increased CO2 could improve wheat yield under future climate in most wheat producing regions (with adequate rainfall) of Ethiopia. Our results provide valuable information regarding impacts of climate change factors and adaptation strategies for producers, researchers, extension professionals and policy makers.


Assuntos
Mudança Climática , Triticum , Aclimatação , Secas , Etiópia
2.
Int J Tuberc Lung Dis ; 23(6): 728-734, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31315706

RESUMO

OBJECTIVE To examine the use of symptoms, chest X-ray (CXR) abnormalities, and combinations of symptoms and CXR in excluding active pulmonary tuberculosis (TB) before treating for latent tuberculous infection (LTBI) in high TB burden countries. METHODS We updated a systematic review and meta-analysis of studies on the sensitivities, specificities, predictive values, diagnostic odds ratios and areas under the curve for index tests. The analysis was conducted using the hierarchical summary receiver operating characteristic method in R software. RESULTS We included 24 publications in the systematic review and meta-analysis. 'Any CXR abnormality' had the highest sensitivity (94.1%, 95%CI 85.8-97.7) among all index tests. 'CXR abnormality suggestive of TB' had a higher specificity (92.2%, 95%CI 89.7-94.1) than 'any CXR abnormality' (86.8%, 95%CI 79.7-91.7). The sensitivity for 'any TB symptom' was 73.0% (95%CI 64.1-80.4), while 'prolonged cough' of ≥2 weeks had a specificity of 94.3% (95%CI 92.2-95.9). There was no significant difference in the sensitivity and specificity of all screening tools stratified by human immunodeficiency virus (HIV) settings, with the exception of 'CXR abnormality suggestive of TB', which had a significantly higher sensitivity in low than in high HIV prevalence settings (effect estimate 2.26, 95%CI 0.69-3.82; P = 0.002). CONCLUSION In countries with a high TB burden, the absence of any TB symptom and any CXR abnormality can be used to exclude active pulmonary TB before initiating treatment for LTBI in household contacts aged ≥5 years of patients with bacteriologically confirmed pulmonary TB. .


Assuntos
Programas de Rastreamento , Tuberculose Pulmonar/epidemiologia , Países em Desenvolvimento , Características da Família , Humanos , Prevalência , Sensibilidade e Especificidade , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/prevenção & controle
3.
Sci Rep ; 8(1): 14653, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30279447

RESUMO

Continued economic relevancy of soybean is a function of seed quality. The objectives of this study were to: (i) assess the spatial association between soybean yield and quality across major US soybean producing regions, (ii) investigate the relationship between protein, oil, and yield with amino acids (AAs) composition, and (iii) study interrelationship among essential AAs in soybean seed. Data from soybean testing programs conducted across 14 US states from 2012 to 2016 period (n = 35,101 data points) were analyzed. Results indicate that for each Mg ha-1 yield increase, protein yield increased by 0.35 Mg protein ha-1 and oil yield improved by 0.20 Mg oil ha-1. Essential AA concentrations exhibit a spatial autocorrelation and there was a negative relationship between concentration of AA, protein, and oil, with latitude. There was a positive interrelationship with different degree of strength among all AAs, and the correlation between Isoleucine and Valine was the strongest (r = 0.93) followed by the correlation among Arginine, Leucine, Lysine, and Threonine (0.71 < r < 0.88). We concluded that the variability in genotype (G) x management (M) x environment (E) across latitudes influencing yield also affected soybean quality; AA, protein, and oil content in a similar manner.


Assuntos
Produção Agrícola , Glycine max/química , Valor Nutritivo , Sementes/química , Aminoácidos/análise , Proteínas de Plantas/análise , Óleo de Soja/análise , Análise Espacial , Estados Unidos
4.
Environ Entomol ; 44(4): 1265-74, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26314073

RESUMO

The host plant range of pests can have important consequences for its evolution, and plays a critical role in the emergence and spread of a new pest outbreak. This study addresses the ecological genetics of the indigenous African maize stem borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae), in an attempt to investigate the evolutionary forces that may be involved in the recent host range expansion and establishment of this species in Ethiopian and southern African sugarcane. We used populations from Ethiopia, Zimbabwe, and South Africa to examine whether the host range expansion patterns shared by the Ethiopian and the southern African populations of B. fusca have evolved independently. Base-pair differences in the cytochrome oxidase I (COI) gene were used to characterize haplotype diversity and phylogenetic relationships. There were seven haplotypes among the 30 sequenced individuals collected on four host plant species from 17 localities in the four countries. Of the seven COI haplotypes identified, the two major ones occurred in both sugarcane and maize. Genetic analyses revealed no detectable genetic differentiation between southern African B. fusca populations from maize and sugarcane (FST = 0.019; P = 0.24). However, there was strong evidence of variation in genetic composition between populations of the pest from different geographic regions (FST = 0.948; P < 0.001). The main implication of these findings is that the B. fusca populations in maize in southern Africa are more likely to shift to sugarcane, suggesting that ecological opportunity is an important factor in host plant range expansion by a pest.


Assuntos
Evolução Biológica , Variação Genética , Herbivoria , Mariposas/fisiologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Etiópia , Haplótipos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Mariposas/genética , Filogenia , Análise de Sequência de DNA , África do Sul , Especificidade da Espécie , Zimbábue
5.
s.l; Evidence-Informed Policy Network (EVIPNet); 2014. 34 p.
Monografia em Inglês | PIE | ID: biblio-1007683

RESUMO

The purpose of this report is to inform deliberations among policymakers and stakeholders. It summarises the best available evidence regarding the design and implementation of policies for improving health care financing. The report was prepared as a background document to be discussed at meetings attended by those engaged in developing policies on health care financing and people with an interest in such policies (stakeholders). It is not intended to prescribe or proscribe specific options or implementation strategies. Rather, its purpose is to allow policy makers and stakeholders to systematically and transparently consider the available evidence about the likely impacts of different options improving health care financing in Ethiopia.


Assuntos
Humanos , Atenção Primária à Saúde/organização & administração , Sistemas de Saúde/economia , Assistência Hospitalar/economia , Etiópia
6.
Addis Ababa; Ethiopian Public Health Institute; 2014. 36 p.
Monografia em Inglês | PIE | ID: biblio-1007282

RESUMO

The purpose of this report is to inform deliberations among policymakers and stakeholders. It summarises the best available evidence regarding the design and implementation of policies for improving skilled birth attendance. The report was prepared as a background document to be discussed at meetings attended by those engaged in developing policies on skilled birth attendance and people with an interest in such policies (stakeholders). It is not intended to prescribe or proscribe specific options or implementation strategies. Rather, its purpose is to allow policy makers and stakeholders to systematically and transparently consider the available evidence about the likely impacts of different options improving skilled birth in Ethiopia.


Assuntos
Humanos , Feminino , Gravidez , Sistemas de Saúde/organização & administração , Saúde Materno-Infantil , Centros de Assistência à Gravidez e ao Parto/provisão & distribuição , Etiópia/epidemiologia
7.
Afr Health Sci ; 12(3): 339-44, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23382750

RESUMO

BACKGROUND: The genotyping of Mycobacterium tuberculosis strains is important to have unique insights into the dissemination dynamics and evolutionary genetics of this pathogen and for TB control as it allows the detection of suspected outbreaks and the tracing of transmission chains. OBJECTIVE: To characterize M. tuberculois isolates collected from newly diagnosed pulmonary TB patients in Addis Ababa METHODS: One hundred and ninety two sputum samples were cultured on Löwenstein-Jensen (LJ) slants and isolates were heat killed for molecular genotyping. The isolates were characterized using spoligotyping and were compared with the International SpoIDB4 database. RESULT: T genotype constitutes the most predominant in our study (95, 49.5%) followed by the CAS genotype (42, 21.9%). Other genotypes found were Haarlem (H) (24, 12.5%), the LAM (3, 1.5%), the Beijing genotype (1, 0.5%); four (2.1%) isolates were designated as Unknown. CONCLUSION: All the isolates belong to the modern lineage and there is high clustering in the genotype of isolates which indicated the presence of recent TB transmission. Therefore, the Tuberculosis Control Programme needs to do more in advocating and strengthening the health system for early detection and treatment of active TB cases as delay in treatment is the key factor in disease transmission.


Assuntos
Variação Genética , Genótipo , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Tuberculose/prevenção & controle , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Análise por Conglomerados , Etiópia/epidemiologia , Feminino , Técnicas de Genotipagem/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Fatores Socioeconômicos , Escarro/microbiologia , Tuberculose/microbiologia , Adulto Jovem
8.
Commun Agric Appl Biol Sci ; 75(3): 423-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21539263

RESUMO

The African sugarcane stalk borer, Eldona saccharina Walker (Lepidoptera: Pyralidae), is widely distributed throughout sub-Saharan Africa and is an important insect pest of maize and sugarcane. The insect shows significant variation in behaviour, host plant and natural enemy guild in different regions. Several attempts to redistribute the natural enemies of E. saccharina from West Africa to South Africa were unsuccessful. The significant behavioural, host plant and natural enemy variations as well as failures of biocontrol attempts evoked a hypothesis of genetic diversification. To evaluate this hypothesis a molecular analysis was conducted on geographically isolated populations of E. saccharina from East, North, South and West Africa, using the cytochrome c oxidase subunit I (COI) region of the mitochondrial genome. The results revealed that E. saccharina populations are separated into four major units corresponding to the West Africa, Rift Valley, South/East Africa and southern African populations. Mitochondrial DNA divergence among the four populations ranged from 1% to 4.98%. To examine the impact of the observed genetic variation on the fertility of inter-population crosses, a mating experiment was conducted between the Rift valley and South African population to produce an F1 generation, and these were backcrossed with the South African parent population. Fertility of eggs produced by the F1/parent population cross was significantly reduced when compared to fertility of the "true" South African line, and the F1/F1 cross. The contributions of the observed genetic differences and inter population incompatibility for the failure of previous biocontrol attempts are discussed and recommendations on future biocontrol practices are given.


Assuntos
Controle de Insetos/métodos , Mariposas/genética , Controle Biológico de Vetores/métodos , África Subsaariana , Animais , DNA Mitocondrial/genética , Demografia , Feminino , Variação Genética , Masculino , Filogenia
9.
J Econ Entomol ; 101(3): 686-91, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18613566

RESUMO

Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) is used as a classical biological control agent against Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), a serious exotic pest of cereal crops in eastern and southern Africa. This parasitoid has been introduced into several African countries for the control of C. partellus in maize, Zea mays L., and sorghum, Sorghum bicolor (L.), but it has never been released in Ethiopia. It is hypothesized that it spread into Ethiopia from populations released in Kenya and Somalia to become the predominant parasitoid of C. partellus in maize and sorghum fields of the country. In recent surveys conducted in Ethiopia, C. flavipes was recovered from C. partellus in sugarcane, Saccharum L. spp. hybrids, at a site >2,000 km from the nearest known release sites in Kenya and Somalia. These findings question published hypotheses that estimate the dispersal rate of C. flavipes to be 60 km per year in Africa, and they suggest that since its release in Africa this parasitoid has developed strains adapted to searching particular host plants infested by particular stem borers. The anomalies between our results and previous reports evoked the hypothesis that C. flavipes in Ethiopian sugarcane might be a different strain. To test this hypothesis, we compared partial COI gene sequences of C. flavipes collected from sugarcane in Ethiopia and those of specimens from other African countries to determine the origin of the Ethiopian population. In addition, COI sequences were obtained for C. flavipes from other continents. The C. flavipes population established in Ethiopian sugarcane is most closely related to the populations released against C. partellus in maize in other parts of Africa, which were derived from the original population imported from Pakistan. The dispersal rate of the parasitoid was estimated to be >200 km per year.


Assuntos
Himenópteros/fisiologia , Controle Biológico de Vetores/métodos , Saccharum , Vespas , Animais , DNA/classificação , DNA/genética , DNA/isolamento & purificação , Etiópia , Amplificação de Genes , Filogenia , Reação em Cadeia da Polimerase , Vespas/genética
10.
Artigo em Inglês | AIM (África) | ID: biblio-1261683

RESUMO

Background: Blindness due to trachomatous trichiasis can be prevented by simple eyelid surgery that can be performed by trained nurses. Objective: To evaluate the post- operative outcome of posterior tarsal rotation done by integrated eye care workers (IECWs) at the twelfth postoperative month. Methods: A prospective study to evaluate trichiasis surgery for recurrence was conducted in Yilmana Densa District. Trained IECWs did transverse tarsotomy with lid margin rotation for 455 patients with trichiasis following the standard procedure. Post-operative follow-up evaluation was done at the 12th month by IECWs who neither took part in the operation nor knew the specific surgeons for the corresponding patients. Results: Out of 695 a total of 560 operated eyelids were available for follow-up just at the 12th month. In terms of persons; 79.3(361/455) patients came for follow-up evaluation. The recurrence rate among the operated eyelids was found to be 16.6. There was an increase in likelihood of having recurrence with increasing age of patients (X2=5.6; P=0.02). We also found a statistically significant difference in rates of recurrence among patients operated by different surgeons(X2 =12.8; P=0.005). Conclusion: Trichiasis recurrence following surgery done by non-ophthalmologists is low indica- ting the possibility of avoiding preventable blindness due to trachoma through the training of integrated eye care workers. Moreover; monitoring mechanism appeared essential to track the performance of IECWs


Assuntos
Catarata , Pálpebras , Procedimentos Cirúrgicos Oftalmológicos , Estudos Prospectivos , Tracoma
11.
Bull Entomol Res ; 96(5): 497-504, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17092361

RESUMO

Surveys for sugarcane stem borers were undertaken in Ethiopia to determine the prevalence and distribution of these and their natural enemies in crops and indigenous host plants. Eldana saccharina Walker was not recovered from sugarcane, but was present in three indigenous wetland sedges, Cyperus papyrus, C. fastigiatus and C. dives in the southern, central and northern part of the country. The latter indigenous host plant was present in waterways adjacent to sugarcane on the commercial sugar estates. The tachinids Schembria eldanae Barraclough and Actia sp. were common parasitoids of E. saccharina larvae in these indigenous sedges. The braconid Dolichogenidea sp. was recovered from E. saccharina larvae in C. dives. Pathogens comprising Beauveria bassiana, Bacillus thuringiensis and Entomophthora sp., were found to be important mortality factors of E. saccharina larvae in the indigenous sedges. The occurrence of E. saccharina in Ethiopia is reported for the first time, and the host plant preferences of the borer and its indigenous natural enemies found during the surveys are recorded. In addition, its potential threat to sugarcane production in Ethiopia is discussed.


Assuntos
Cyperus/parasitologia , Mariposas/fisiologia , Animais , Bacillus thuringiensis/fisiologia , Beauveria/fisiologia , Dípteros/fisiologia , Entomophthora/fisiologia , Etiópia , Cadeia Alimentar , Geografia , Mariposas/microbiologia , Mariposas/parasitologia , Saccharum/parasitologia , Vespas/fisiologia
12.
Trans R Soc Trop Med Hyg ; 100(1): 48-52, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16203020

RESUMO

A fast agglutination screening test (FAST) for the detection of Leishmania antibodies in human serum samples was evaluated under harsh field conditions in northern Ethiopia. Test performance was compared with a standard serological test, namely the direct agglutination test (DAT), and with parasitology. In total, 103 suspected cases were recruited for the study. Based on parasitological examination, 49 patients were confirmed of having visceral leishmaniasis (VL) and the other 54 suspected cases were parasitologically negative. Field evaluation of FAST was possible in blood samples of 89 patients. FAST had 4 false negative results and 13 false positive results. DAT had 2 false negative results and 20 false positive results. A good degree of agreement (86.9%) was observed between FAST and DAT (kappa value 0.73). In this field-based evalauation, the sensitivity and specificity of FAST were found to be 91.1% (95% CI 77.9-97.1) and 70.5% (95% CI 54.6-82.8), respectively, compared with 95.3% (95% CI 82.9-99.2) and 62.3% (95% CI 47.9-74.9) for DAT. FAST had a high predictive value of a negative test, demonstrating that FAST could be utilised to exclude rapidly non-VL patients from a large population of suspects with fever and splenomegaly in endemic areas.


Assuntos
Anticorpos Antiprotozoários/sangue , Leishmaniose Visceral/diagnóstico , Testes de Aglutinação/métodos , Testes de Aglutinação/normas , Etiópia , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Leishmaniose Visceral/sangue , Sensibilidade e Especificidade
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