OALib Journal期刊

ISSN: 2333-9721



匹配条件: “ Mumba Djamba” ,找到相关结果约28条。
Evaluation of Yield and Competition Indices for Intercropped Eight Maize Varieties, Soybean and Cowpea in the Zone of Savanna of South-West RD Congo  [PDF]
Pongi Khonde, Kabongo Tshiabukole, Mbuya Kankolongo, Stefan Hauser, Mumba Djamba, Kizungu Vumilia, Kabwe Nkongolo
Open Access Library Journal (OALib Journal) , 2018, DOI: 10.4236/oalib.1103746
In order to enhance the legumes potential advantages on the cereal yield in intercropping system by nitrogen direct transfer from legume to cereal, an intercropping experiment was conducted between eight maize varieties (07SADVE, 08SADVE 1, 09SADVE F2, Mudishi 1, Mudishi 3, VP0523, ZM538 and Samaru), cowpea (Vigna unguiculata var. H4) and soybean (Glycine max var. Vuangi) during November 2011-February 2012 season at INERA/Mvuazi in the south-western country of DR Congo. The experimental design was a Split plot with four replications, twenty six treatments were applied between maize varieties monocrops (40.000 plant·ha﹣1) and legumes in monoculture (360.000 plant·ha﹣1) and both of sole planting were combined. Evaluation of these soles planting was performed on basis of several intercropping indices (MYE, LER, ATER, RCC, A and CR), the monetary advantage index (MAI), Actual Yield Loss index (AYL) and intercropping index (IA). After data analysis, competitivity indices indicated the higher yields advantages of maize varieties in intercropping, especially Mudishi 3-soybean (MYE = 2836.300 kg·ha﹣1). The equivalent land ratio (LER) varied with 08SADVE 1variety between 0.70 and 1.66 in cowpea and soybean intercrops respectively, the Relative crowding coefficient (RCC) showed yield advantage of all intercrops except with 09SADVE F2, Mudishi 1 and 07SADVE. Aggressivity (A) showed dominance of maize in all intercrops, against the Competitive ratio (CR) showed that the competitivity was stronger on cowpea (from 16.42 to 98.63) than soybean (from 16.12 to 25.70). Actual yield loss (AYL) was negative in all intercrops with cowpea and soybean. Thus, the index of association (IA) informed that the negative values of the different intercrops were due to the maize price (1000 CDF·kg﹣1) and legumes price (1500 CDF·kg﹣1). Finally, the monetary advantage index (MAI = 922.92) and PCA had determined that intercrop with Mudishi 3-soybean as an economic efficiency intercrop than others mixtures.
Analysis of Adaptive Response of Maize (Zea mays) Varieties from DR-Congo to Water Stress  [PDF]
Jean Pierre Kabongo Tshiabukole, Amand Mbuya Kankolongo, Gertrude Pongi Khonde, Antoine Mumba Djamba, Roger Kizungu Vumilia, Kabwe Nkongolo
American Journal of Plant Sciences (AJPS) , 2017, DOI: 10.4236/ajps.2017.89153
Abstract: Maize production in tropical Africa is often negatively affected by drought. The main objectives of the present study were to 1) analyze the impact of water stress on the agro-morphological performance of two varieties of Quality Protein Maize (QPM) compared to two normal maize varieties and 2) assess their adaptive response in contrasting water environments. Agro-morphological responses to water deficiency of maize (Zea mays L.) were assessed in controlled experiments using four maize varieties, two normal maize (Zm725 and Mus1) and two quality protein maize (Mudishi1 and Mudishi3) varieties. They were subjected to three water regimes (100%, 60%, 30% water retention capacity) at the beginning of the bloom stage, using a Fischer block design with four replications. Significant differences (p < 0.05) among varieties, water regimes and their interactions for plant growth and production parameters were observed. Reduction of water supply to plants caused changes in aerial and underground plant growth. Plant stem height, foliar expansion, and root system development characterizing vegetative growth showed variation in varietal response to water regimes. Mus1 (normal maize variety) was the best adapted to variations in water regimes because they developed an important root volume to adapt to the effects of water deficit while maintaining their morphological and productive characteristics.
Challenges Associated with Serving the Diverse Needs of American Indian Families through Current Provisions of the Indian Child Welfare Act  [PDF]
Sonya Smith, Yanyi K. Djamba
Advances in Applied Sociology (AASoci) , 2015, DOI: 10.4236/aasoci.2015.51003
Abstract: Historical reviews of American Indian Culture reveal an indigenous population rooted in the dichotomy of societal misunderstanding and victimization. This dichotomy illustrates repeated occurrence of incidents involving the removal, assimilation or extinction of American Indian children. This analysis of the Indian Child Welfare Act focuses on the heart of American Indian culture which is the well-being of American Indian children. Information used in this paper comes from the review of literature, census data and oral narratives obtained through a convenience sample of American Indian people interviewed in Alabama. The results of this study reveal the diversity of American Indian people seen throughout the United States, as well as in the state of Alabama. Unfortunately, the provisions of the Indian Child Welfare Act are only intended for American Indian children from federally recognized tribes and exclude American Indian children from state recognized tribes. This study concludes with a discussion of the contributions and limitations of the Indian Child Welfare Act and calls for expanded services to serve all American Indian populations in the United States.
Migration, Sexual Behavior and Perceptions of Risk: Is the Place of Origin a Factor in HIV Infection?  [PDF]
Sitawa R. Kimuna, Yanyi K. Djamba
Advances in Applied Sociology (AASoci) , 2012, DOI: 10.4236/aasoci.2012.23023
Abstract: Migration is an important process of change, especially for populations in developing countries. Just by moving to new places, migrants are different from those who do not migrate in terms of socio-demographic characteristics. This study focuses on migration in Kenya and its interaction with human immunodeficiency virus (HIV) risk. Two main research questions are addressed: To what extend does the sexual behavior of migrants differ from non-migrants? Do migrants know more about HIV risk than non- migrants? The analysis is based on the 2003 Kenya Demographic and Health Survey data. The results show that migrants are significantly more likely to report fear of HIV infection than non-migrants. The perception of risky sexual behavior is significantly correlated with non-use of condoms for migrants than for non-migrants. Migrants who perceive themselves as being at risk of HIV infection are less likely to use a condom at their last non-marital sexual encounter. Also, migration is significantly correlated with multiple sexual partners. There is a remarkable difference in the mean age of migrants and non-migrants; migrants on average are significantly older and more likely to be married than non-migrants.
The State of Sexual Health in the US South: Opportunities and Challenges  [PDF]
Yanyi K. Djamba, Theresa C. Davidson, Mosisa G. Aga
Advances in Applied Sociology (AASoci) , 2012, DOI: 10.4236/aasoci.2012.24039
Abstract: This paper examines the socio-demographic characteristics and the state of sexual health in the US South, a region comprised of 10 states: Alabama, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia. The results show that the region is home to 18 percent of the US population, but its residents are statistically significantly more likely to have lower educational attainment and to live in poverty than other US residents. In addition, residents of the US South have poor sexual health compared to their counterparts living in other regions. Teenagers who live in the US South are more likely to get pregnant and have babies than teenagers in other regions. Likewise, the rates of Chlamydia and Gonorrhea among females age 15 - 19 were higher in the US South than elsewhere in the US. This poor sexual health cost the 10 US South states an estimated $2.3 billion in 2008. The paper concludes with a discussion of the sexual health challenges and opportunities in the US South in light of new federal funding streams that allow for the use of evidence-based approaches in sexual health programs.
The Influence of Race on Employment Status and Earnings of African Immigrant Men in the United States
Yanyi K. Djamba,Sitawa R. Kimuna
International Journal of Population Research , 2011, DOI: 10.1155/2011/305873
Abstract: This paper uses the labor queue theory to examine the changing influence of race on the employment status and earnings of African immigrant men in the United States between 1980 and 2008. The results show that the white advantage echoed in previous research has diminished. Black African immigrant men's chance of being employed is now greater than that of their white counterparts when their sociodemographic characteristics are taken into consideration. However, when human capital factors are included in the regression models, white African immigrant men still maintain a significant advantage in earnings. This study also uncovered differential impacts of marriage and school enrollment on white and black African immigrant men's employment and earnings. These results challenge the use of labor queue theory as a framework for explaining immigrants' experience in the US job market. 1. Introduction Despite the increasing diversity of people living in the United States today, race remains a factor of interest and controversy among researchers and lay persons. This is probably more evident in the labor market where the person’s race is said to affect their chance of employment and earnings. According to the labor queue theory, employers follow a preference ordering in selecting their workforce. In the United States, such preference is primarily based on race [1]. As Waldinger [2] put it, “In a race-conscious society like the United States, employers rank entire groups of people in terms of their ethnic and racial characteristics.” Within the labor queue model, Whites are at the top of the queue, followed by Asians, Hispanics (Hispanics may be of any race [3]), and Blacks. Is the queuing explanation valid for African immigrant men? This study attempts to answer that question by examining differences in employment status and earnings between black and white African men. The composition of the African immigrant male population in the United States has shifted from a white majority (56%) to a black majority (72%) during the period from 1980 to 2008. The change became apparent since 1990 as a result of a sustained economic growth in the United States (pull factor) and mounting economic and political crises in Africa (push factor). Further, it was sustained by the introduction in 1995 of the annual immigration program through which some 50,000 foreign-born people are admitted to the United States and granted permanent resident status. What effect, if any, does such a changing racial composition have on African immigrant men’s chance of employment and earnings in the
Construction of a Small Scale Laboratory for Solar Collectors and Solar Cells in a Developing Country  [PDF]
Gentile Niko, Davidsson Henrik, Bernardo Ricardo, Gomes Joao, Gruffman Christian, Chea Luis, Mumba Chabu, Karlsson Bj?rn
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.51B014
Abstract: In the field of renewable energy, self-provided research in developing countries is barely present, but most welcomed. The creation of know-how and self-development of technologies should reduce the dependence on industrialized countries for both materials and knowledge. This work presents technological and social issues related to the construction of a low budget solar laboratory in Mozambique. The goal is to demonstrate that scientific level research can be carried out in developing countries by using affordable solutions without sacrificing quality of the results. For this investigation, a solar laboratory was built in 2011 at Universidade Eduardo Mondlane of Maputo. The laboratory enables measurements to evaluate solar thermal and photovoltaic-thermal hybrid collectors. Thanks to the flexibility of the system, students and teaching staff can add/remove equipment and develop customised local research programs. In addition, a course on the principles of solar energy and collector simulation for local students was taught. The needed data acquisition devices usually used in Europe were compared with cheaper and easy-maintenance ones. Calibration and estimation of the uncertainty were successfully performed. Approximately 9% of inaccuracy in the measurement was introduced by the cheaper equipment, but the investment cost was reduced by more than 90%. Other issues, results and future recommendations are shown.
Measurements of the Electrical Incidence Angle Modifiers of an Asymmetrical Photovoltaic/Thermal Compound Parabolic Concentrating-Collector  [PDF]
Bernardo Ricardo, Davidsson Henrik, Gentile Niko, Gomes Jo?o, Gruffman Christian, Chea Luis, Mumba Chabu, Karlsson Bj?rn
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.51B007
Abstract: Reflector edges, sharp acceptance angles and by-pass diodes introduce large variations in the electrical performance of asymmetrical concentrating photovoltaic/thermal modules over a short incidence angle interval. It is therefore important to quantify these impacts precisely. The impact on the electrical performance of the optical properties of an asymmetrical photovoltaic/thermal CPC-collector was measured in Maputo, Mozambique. The measurements were carried out with the focus on attaining a high resolution incidence angle modifier in both the longitudinal and transversal directions, since large variations were expected over small angle intervals. A detailed analysis of the contribution of the diffuse radiation to the total output was also carried out. The solar cells have an electrical efficiency of 18% while the maximum measured electrical efficiency of the collector was 13.9 % per active glazed area and 20.9 % per active cell area, at 25 °C. Such data make it possible to quantify not only the electrical performance for different climatic and operating conditions but also to determine potential improvements to the collector design. The electrical output can be increased by a number of different measures, e.g. removing the outermost cells, turning the edge cells 90°, dividing each receiver side into three or four parts and directing the tracking, when used, along a north-south axis.


A CATT Negative Result after Treatment for Human African Trypanosomiasis Is No Indication for Cure
Veerle Lejon ,Dieudonné Mumba Ngoyi,Marleen Boelaert,Philippe Büscher
PLOS Neglected Tropical Diseases , 2010, DOI: 10.1371/journal.pntd.0000590
Abstract: Background Cure after treatment for human African trypanosomiasis (HAT) is assessed by examination of the cerebrospinal fluid every 6 months, for a total period of 2 years. So far, no markers for cure or treatment failure have been identified in blood. Trypanosome-specific antibodies are detectable in blood by the Card Agglutination Test for Trypanosomiasis (CATT). We studied the value of a normalising, negative post-treatment CATT result in treated Trypanosoma brucei (T.b.) gambiense sleeping sickness patients as a marker of cure. Methodology/Principal Findings The CATT/T.b. gambiense was performed on serum of a cohort of 360 T.b. gambiense patients, consisting of 242 primary and 118 retreatment cases. The CATT results during 2 years of post-treatment follow-up were studied in function of cure or treatment failure. At inclusion, sensitivity of CATT was 98% (234/238) in primary cases and only 78% (91/117) in retreatment cases. After treatment, the CATT titre decreased both in cured patients and in patients experiencing treatment failure. Conclusions/Significance Though CATT is a good test to detect HAT in primary cases, a normalising or negative CATT result after treatment for HAT does not indicate cure, therefore CATT cannot be used to monitor treatment outcome.
A Rapid Assessment of Avoidable Blindness in Southern Zambia
Robert Lindfield, Ulla Griffiths, Fiammetta Bozzani, Musonda Mumba, Joseph Munsanje
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0038483
Abstract: Introduction A rapid assessment of avoidable blindness (RAAB) was conducted in Southern Zambia to establish the prevalence and causes of blindness in order to plan effective services and advocate for support for eye care to achieve the goals of VISION 2020: the right to sight. Methods Cluster randomisation was used to select villages in the survey area. These were further subdivided into segments. One segment was selected randomly and a survey team moved from house to house examining everyone over the age of 50 years. Each individual received a visual acuity assessment and simple ocular examination. Data was recorded on a standard proforma and entered into an established software programme for analysis. Results 2.29% of people over the age of 50 were found to be blind (VA <3/60 in the better eye with available correction). The major cause of blindness was cataract (47.2%) with posterior segment disease being the next main cause (18.8%). 113 eyes had received cataract surgery with 30.1% having a poor outcome (VA <6/60) following surgery. Cataract surgical coverage showed that men (72%) received more surgery than women (65%). Discussion The results from the RAAB survey in Zambia were very similar to the results from a similar survey in Malawi, where the main cause of blindness was cataract but posterior segment disease was also a significant contributor. Blindness in this part of Zambia is mainly avoidable and there is a need for comprehensive eye care services that can address both cataract and posterior segment disease in the population if the aim of VISION 2020 is to be achieved. Services should focus on quality and gender equity of cataract surgery.

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