Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 9 )

2018 ( 15 )

2017 ( 13 )

2016 ( 14 )

Custom range...

Search Results: 1 - 10 of 2493 matches for " Marcel Muengula-Manyi "
All listed articles are free for downloading (OA Articles)
Page 1 /2493
Display every page Item
Incidence, Severity and Gravity of Cassava Mosaic Disease in Savannah Agro-Ecological Region of DR-Congo: Analysis of Agro-Environmental Factors  [PDF]
Marcel Muengula-Manyi, Kabwe K. Nkongolo, Claude Bragard, Patrick Tshilenge-Djim, Stephan Winter, Adrien Kalonji-Mbuyi
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.34061
Abstract: African Cassava mosaic disease (ACMD) is the most severe and widespread disease caused by viruses limiting production of the crop in sub-Saharan Africa. The objective of the present study was to evaluate CMD incidence, severity, and gravity under different agro-environmental conditions. A total of 222 fields were surveyed in 23 different locations. All the farmers grow only local cassava varieties without applications of fertilizers. Overall, mean CMD incidences for all sites surveyed were 58.2% and 51.7%, in 2009 and 2010, respectively. Disease severity ranged from 2.4 to 3.1 on a scale of 1 to 5. Mean disease gravity varied from 29.7% to 62%, in 2010, and 2009, respectively. Detailed analysis of agronomic and environmental revealed no significant association between cassava stand locations, age, land topography and the development of CMD. Likewise intercropping practices and field topping did not affect the development of CMD in all the fields surveyed. There were significant differences in the number of white flies (Bemisia tabaci) per plant in 2009 and 2010, but no significant correlations between the number of B. tabaci per plant and CMD incidence, severity, and gravity was found. In most fields, CMD appears to originate mostly from unhealthy cassava cuttings used for planting.
Assessing Reactions of Genetically Improved and Local Cassava Varieties to Cassava Mosaic Disease (CMD) Infection in a Savannah Region of the DR-Congo  [PDF]
Marcel Muengula-Manyi, Lyna Mukwa, Kabwe K. Nkongolo, Patrick Tshilenge-Djim, Stephan Winter, Claude Bragard, Adrien Kalonji-Mbuyi
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.44101

The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varieties were planted using randomized complete block design with three replications. The rate of cuttings sprouted varied significantly from variety to variety and from location to location. Local varieties were severely infected than improved varieties throughout the trial period. In general, the level of CMD incidence for genetically improved varieties was below 15% while it reached 100% for the local cassava varieties six months after planting (MAP). This trend was also observed for the CMD severity and gravity. The mean scores for CMD severity were 2 and 3.6 for genetically improved and local varieties, respectively at 6 MAP. CMD gravity for improved varieties was below 21% for genetically improved varieties and exceeded 85% for local varieties at the end of trials. Area Under the Severity index Progress Curve (AUSiPC) and Area Under Disease Progress Curve (AUDPC) estimates confirmed that improved varieties were moderately infested comparatively to local varieties. Molecular analysis is being conducted to determine the genetic variability and complexity of the cassava mosaic virus strains involved.

Occurrence and Distribution of Banana bunchy top virus Related Agro-Ecosystem in South Western, Democratic Republic of Congo  [PDF]
Lyna Fama Tongo Mukwa, M. Muengula, I. Zinga, A. Kalonji, M. L. Iskra-Caruana, C. Bragard
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.55079

Banana bunchy top virus (BBTV) is one of the most severe and widespread virus limiting production and distribution of planting material of banana (Musa spp.) crops in the world. In Democratic Republic of Congo (DRC), these crops play a major role in daily life of almost 70% of citizen. Many factors influence banana production negatively such as Banana bunchy top disease. Epidemiological survey was conducted in experimental stations and farmers’ fields for two consecutive seasons covering 72 sites in five provinces of south western of RDC. The objective of this study was to evaluate the presence and distribution of the Banana bunchy top virus in five provinces of South Western of DRC, with emphasis on the agro-ecological factors. A total of 174 Musa spp. leaves samples were collected and analyzed by PCR. The results revealed the presence of BBTV in all provinces investigated. The frequency of BBTV was 6.3% in Bandundu, 12.1% in Kasa?Oriental, 17.8% Bas Congo, 1.1% in Katanga and 7.5% Kinshasa Urban and Peri-urban. Results also revealed that BBTV occurred in experimental station and farmers’ fields, both having all cooking and dessert bananas. The high prevalence of BBTV seemed to be linked to multiple introductions of planting materials in the Bas Congo province during 1990 and 2002. However, the province of Katanga had not experienced the introduction of planting material. This factor would explain the lowest prevalence of Banana bunchy top virus in this province. The results indicated that there was a real need to facilitate access to genetically improved and healthy certified planting material in these provinces.

Clinical Usefulness of Measuring Red Blood Cell Distribution Width in Patients with Hepatitis B
YuFeng Lou, ManYi Wang, WeiLin Mao
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037644
Abstract: Background Red blood cell distribution width (RDW), an automated measure of red blood cell size heterogeneity (e.g., anisocytosis) that is largely overlooked, is a newly recognized risk marker in patients with cardiovascular diseases, but its role in persistent viral infection has not been well-defined. The present study was designed to investigate the association between RDW values and different disease states in hepatitis B virus (HBV)-infected patients. In addition, we analyzed whether RDW is associated with mortality in the HBV-infected patients. Methodology/Principal Findings One hundred and twenty-three patients, including 16 with acute hepatitis B (AHB), 61 with chronic hepatitis B (CHB), and 46 with chronic severe hepatitis B (CSHB), and 48 healthy controls were enrolled. In all subjects, a blood sample was collected at admission to examine liver function, renal function, international normalized ratio and routine hematological testing. All patients were followed up for at least 4 months. A total of 10 clinical chemistry, hematology, and biochemical variables were analyzed for possible association with outcomes by using Cox proportional hazards and multiple regression models. RDW values at admission in patients with CSHB (18.30±3.11%, P<0.001), CHB (16.37±2.43%, P<0.001) and AHB (14.38±1.72%, P<0.05) were significantly higher than those in healthy controls (13.03±1.33%). Increased RDW values were clinically associated with severe liver disease and increased 3-month mortality rate. Multivariate analysis demonstrated that RDW values and the model for end-stage liver disease score were independent predictors for mortality (both P<0.001). Conclusion RDW values are significantly increased in patients with hepatitis B and associated with its severity. Moreover, RDW values are an independent predicting factor for the 3-month mortality rate in patients with hepatitis B.
Making Sense of Environmental Complexity in a Reform Context: The Case of Megaproject Alpha  [PDF]
Marcel Veenswijk
American Journal of Industrial and Business Management (AJIBM) , 2012, DOI: 10.4236/ajibm.2012.24015
Abstract: In this paper, new concepts on environmental complexity and sense making are developed and explored and analysed. The article based on a case study regarding a public-private collaboration in a Dutch infrastructural mega project. It is argued that the ability to influence the direction of the change process of the mega project “Alpha” depends on the way actors are able to influence the so aleed “cultural interfaces” into the power arena by means of a specific group of organizational stakeholders. After a short theoretical introduction, we describe the case in terms of two dominant cultural stages and their specific interface dynamics. The paper concludes with a general reflection on the central concepts.
Treatment of Helicobacter pylori infections: Mitigating factors and prospective natural remedies
CE Manyi-Loh, AM Clarke, NF Mkwetshana, RN Ndip
African Journal of Biotechnology , 2010,
Abstract: Helicobacter pylori is a Gram-negative, microaerophilic spiral or motile rod that infects about half the world’s population with a very high prevalence in the developing world. It is an important aetiological factor in the development of gastritis, peptic ulcer disease, gastric atrophy and B cell mucosa associated lymphoid tissue (MALT) lymphoma. H. pylori infection is responsible for a significant cause of morbidity and mortality imposing a major burden on health care systems world wide. The high prevalence of infection in the developing countries has been attributed to poor socioeconomic status and sanitation as well as an increased trend of antibiotic resistance. Antimicrobial chemotherapy (two antibiotics and a proton pump inhibitor) employed for the treatment of H. pylori infections has emerged as the most important means to resolve these infections. However, antimicrobial therapy is fraught with a number of inherent limitations such as resistance, cost of treatment, unavailability of drugs in rural areas and undesirable side effects necessitating the need to search for alternative approaches from natural sources including vegetables, honey and probiotics amongst others. These could form the basis of novel low cost, efficient, large-scale and alternative/complementary solutions with minimal side effects to decrease or eradicate H. pylori infections in the future.
Limb reconstruction surgery in China: an evaluation of its role in the largest developing nation
Lei Huang,Liang He,Jie Wei,Manyi Wang
Strategies in Trauma and Limb Reconstruction , 2007, DOI: 10.1007/s11751-007-0020-x
Abstract: China is the “economic tiger” of the twenty-first century. Its new economic policies have overturned the outlook and futures of many industries in this nation, and parallel to this industrial progress have been strides in medicine. However a country steeped in a history of several millennia does not replace generations of experience nor knowledge in a few decades. The author explores the history of limb reconstruction surgery in this country, setting it in context of a population exposed to both traditional Chinese medicine and Western medicine.
Narrating National Geo Information Infrastructures: Balancing Infrastructure and Innovation  [PDF]
Henk Koerten, Marcel Veenswijk
Journal of Service Science and Management (JSSM) , 2009, DOI: 10.4236/jssm.2009.24040
Abstract: This paper examines narratives relating to the development of National Geo Information Infrastructures (NGII) in ethnographic research on a Dutch NGII project which was monitored throughout its course. We used an approach which focuses on narratives concerning the environment, groups and practice to elicit sense-making processes. We assert that narratives are relatively fixed and that they only change under specific circumstances. Moreover, the fixing of or change in narratives takes place in practice, so our research approach aimed at analysing narratives of practice, which we label ‘storyboards’. For this purpose, project meetings and conferences were observed, key persons both within and outside the project environment were interviewed, and an analysis of relevant documents and video footage was undertaken. Storyboards are created by actors as a result of day-to-day challenges related to project goals, technology and infrastructure. In our research we found that these storyboards occur as vicious circles from which actors cannot escape. In the specific case analysed, our interpretation of the narrative storyboards suggested that these vicious circles are caused by the inability of project participants to distinguish between infrastructure and innovation requirements in their daily work.
A Value-Based and Multi-Level Model of Macro Economies  [PDF]
Marcel van Marrewijk
Technology and Investment (TI) , 2010, DOI: 10.4236/ti.2010.11005
Abstract: There is sufficient evidence that performance levels of various economic systems differ. All systems seem to have particular benefits, but all of them are adequately aligned with the dynamics and complexity of con-temporary societies. In this paper, the author introduces a sequence of ideal type economic systems, based on Spiral Dynamics, a theory explaining levels of existence within people, groups of people, organizations and societies. Per type the author elaborates on the underlying value systems and relating institutional structures, such as leadership style, governance and measurement format.
A Typology of Institutional Frameworks for Organizations  [PDF]
Marcel Van Marrewijk
Technology and Investment (TI) , 2010, DOI: 10.4236/ti.2010.12012
Abstract: Inspired by Dr. Clare Graves’ research on evolutionary developments in value systems and levels of existence, this paper introduces an integral business framework—a sequence of ideal type organizations—each characterized by specific institutional arrangements. A table—the transition matrix—summarizes the specific features of each type. It is an update of former version based upon an international EU-financed ECSF research project [1].
Page 1 /2493
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.