Social networks and information access: Implications for agricultural extension in a rice farming community in northern Vietnam     

Lan Anh Hoang  Jean-Christophe Castella  Paul Novosad 《Agriculture and Human Values》2006,23(4):513-527

Village communities are not homogeneous entities but a combination of complex networks of social relationships. Many factors such as ethnicity, gender, socio-economic status, and power relations determine one’s access to information and resources. Development workers’ inadequate understanding of local social networks, norms, and power relations may further the interests of better-off farmers and marginalize the poor. This paper explores how social networks function as assets for individuals and households in the rural areas of developing countries and influence access to information and benefits from research and development. A case study of such networks in Phieng Lieng village, in the northern mountains of Vietnam, provides evidence for the need for the efficient delivery of extension services and research and development interventions at the micro level. Lan Anh Hoang is a social scientist with a special interest in social networks and gender and power relations in rural areas. She is currently working on her PhD at the School of Development Studies, University of East Anglia (UK) on “Gender relations, household power hierarchies, and social norms in migration decision-making in rural Vietnam.” She was involved in the Mountain Agrarian Systems Program in Bac Kan Province from 1999 to 2002. Jean -Christophe Castella is a production systems agronomist from the Institut de Recherche pour le Développement (IRD, France). Between 1998 and 2003, he coordinated a joint research program on “comprehensive study of land use changes in northern Vietnam uplands” in partnership with the Vietnam Agricultural Science Institute (VASI, Hanoi, Vietnam) and the International Rice Research Institute (IRRI, Philippines). Paul Novosad was involved with the Mountain Agrarian Systems program from January to July 2002. He helped to synthesize the results of field research and also was involved in analyzing data related to social networks. Since fall 2002 he studies Public Administration and International Development at the Kennedy School of Government in the United States (Cambridge, Massachusetts).  相似文献   

Evolutionary and biomedical insights from the rhesus macaque genome   总被引：1，自引：0，他引：1  

Rhesus Macaque Genome Sequencing  Analysis Consortium  Gibbs RA  Rogers J  Katze MG  Bumgarner R  Weinstock GM  Mardis ER  Remington KA  Strausberg RL  Venter JC  Wilson RK  Batzer MA  Bustamante CD  Eichler EE  Hahn MW  Hardison RC  Makova KD  Miller W  Milosavljevic A  Palermo RE  Siepel A  Sikela JM  Attaway T  Bell S  Bernard KE  Buhay CJ  Chandrabose MN  Dao M  Davis C  Delehaunty KD  Ding Y  Dinh HH  Dugan-Rocha S  Fulton LA  Gabisi RA  Garner TT  Godfrey J  Hawes AC  Hernandez J  Hines S  Holder M  Hume J  Jhangiani SN 《Science (New York, N.Y.)》2007,316(5822):222-234

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Negative epistasis between beneficial mutations in an evolving bacterial population     

Khan AI  Dinh DM  Schneider D  Lenski RE  Cooper TF 《Science (New York, N.Y.)》2011,332(6034):1193-1196

Epistatic interactions between mutations play a prominent role in evolutionary theories. Many studies have found that epistasis is widespread, but they have rarely considered beneficial mutations. We analyzed the effects of epistasis on fitness for the first five mutations to fix in an experimental population of Escherichia coli. Epistasis depended on the effects of the combined mutations--the larger the expected benefit, the more negative the epistatic effect. Epistasis thus tended to produce diminishing returns with genotype fitness, although interactions involving one particular mutation had the opposite effect. These data support models in which negative epistasis contributes to declining rates of adaptation over time. Sign epistasis was rare in this genome-wide study, in contrast to its prevalence in an earlier study of mutations in a single gene.  相似文献   

RAPD variability in rice (Oryza sativa L.) plants derived from desiccation-tolerant calli     

Dinh Thi Phong  Le Thi Muoi  Le Tran Binh 《Euphytica》2001,121(3):297-303

Genetic modification from selfed progenies of 18 rice (Oryza sativa L.) plants regenerated from callus tissues which survived desiccation, were investigated at the DNA level using the random amplified polymorphic DNA (RAPD) method. Twelve 10-mer random primers were used to amplify DNA of progenies from the regenerated plants, and a total of 228 PCR products and 1780 DNA fragments were obtained by primers, generating between four to thirteen major bands. The size of the amplified fragments ranged from 0.2 to 2.55 kb. The results showed that 10 out of 12 primers produced polymorphic bands, two primers (RA31 and RA185) showed no polymorphism among plants tested. A dendrogram of the genetic distance was constructed based on their polymorphism, demonstrating that somaclonal variation exists in rice plants regenerated from callus which survived the desiccation treatment. Part of this variation can be useful in rice breeding. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

The phenotypic characteristics and relational database for Vietnamese native pig populations     

Shinya Ishihara  Fukuhiro Yamasaki  Pham Hai Ninh  Nguyen Cong Dinh  Aisaku Arakawa  Masaaki Taniguchi  Ngo Thi Kim Cuc  Satoshi Mikawa  Masaru Takeya  Kazuhiro Kikuchi 《Animal Science Journal》2020,91(1)

Although there are a number of Vietnamese native pig (VnP) populations, some are on the verge of extinction, and therefore adequate management and conservation are necessary. In this study, we conducted a field survey of VnP populations and analyzed interrelationships among their characteristics. We also established a relational database for management of field data on these populations. For data collection, we conducted interviews with farmers and visual inspection of 32 VnP populations in 22 provinces of Vietnam, as well as taking photographs of individual animals. Data on the characteristics of VnP populations were subjected to multiple correspondence analysis (MCA). For establishment of the database, normalization and table partitioning were performed to eliminate redundancy and ensure consistency of the collected data items. Passport data, characteristics data, and image data were collected from a total of 1,918 VnPs and entered as a normalized table. Upon MCA, most of the populations were not separated from each other, but the Mong Cai, O Lam, and Chu Prong populations were separated from the other populations. Thus, we have constructed a relational database from comprehensive information on the characteristics of VnP populations.  相似文献   

Controlled reproduction of an important indigenous fish species, Spinibarbus denticulatus (Oshima, 1926), in Southeast Asia     

Dinh Van Trung  & Amrit Bart 《Aquaculture Research》2007,38(5):441-451

Aquaculture of Spinibarbus denticulatus (Oshima, 1926), a fish species indigenous to North Vietnam and Eastern China, is constrained by lack of fingerlings for stocking ponds and cages. As these fish do not naturally breed in captivity, carp pituitary extract (CPE), luteinizing hormone-releasing hormone analogue (LHRHa) with domperidone (DOM) and human chorionic gonadotropin (HCG) were administered at various doses to induce ovulation. A first set of experiments evaluated the response to LHRHa (30, 40 and 50 μg kg⁻¹) with or without DOM (10 mg kg⁻¹), CPE (20, 30 and 40 mg kg⁻¹) and HCG (3000, 4000 and 5000 IU kg⁻¹). A second set of experiments evaluated the dose response to LHRHa (30, 35, 40 and 50 μg kg⁻¹) primed with 6 mg kg⁻¹ of CPE, and HCG (3000, 3500, 4000, 5000 IU kg⁻¹) primed with 6 mg kg⁻¹ of CPE. The treatment groups were compared with each other and the control (injected with 0.9% saline solution). Only 25% and 50% ovulation resulted when treated with LHRHa at 40 and 50 μg kg⁻¹, whereas 100% ovulation was achieved with an addition of DOM to LHRHa. Both 30 and 40 mg kg⁻¹ CPE induced 100% ovulation. However, HCG (4000 and 5000 IU kg⁻¹) induced ovulation in only 33% of females. When primed with CPE, the minimum dose of LHRHa required was 35 μg kg⁻¹ to achieve 70% ovulation. Priming HCG with CPE also resulted in 100% ovulation, and the minimum effective dose of HCG to induce ovulation was 3500 IU kg⁻¹ with 60% ovulation. Fertilization and hatch rates observed in this study with different hormonal stimulation were high (80–93%). The results indicate that while the use of combined hormone strategy has no apparent advantage over a single hormone strategy, LHRHa+DOM (40 μg kg⁻¹+10.0 mg kg⁻¹) and CPE (30 mg kg⁻¹) are most effective in consistently inducing ovulation and thus can be used for commercial hatchery production of S. denticulatus larvae.  相似文献   

Use of GIS and machine learning to predict disease in shrimp farmed on the east coast of the Mekong Delta,Vietnam     

Khiem  Nguyen Minh  Takahashi  Yuki  Yasuma  Hiroki  Oanh  Dang Thi Hoang  Hai  Tran Ngoc  Ut  Vu Ngoc  Kimura  Nobuo 《Fisheries Science》2022,88(1):1-13

Diseases in shrimp farms in the Mekong Delta of Vietnam cause significant crop losses and are therefore of great concern to producers. Once a pond becomes infected, it is difficult to prevent spread of the disease to nearby shrimp farming areas. Thus, predicting the occurrence of disease is an essential part of reducing the risk for shrimp farmers. In this study, we applied an integrated geographic information system and machine learning system to predict three serious diseases of shrimp, namely, acute hepatopancreatic necrosis, white spot syndrome disease, and Enterocytozoon hepatopenaei infection, based on data collected from shrimp farms in the Tra Vinh, Bac Lieu, Soc Trang, and Ca Mau provinces of Vietnam. We first constructed a map showing the distribution of these diseases using the locations of affected farms, and then we conducted spatial analysis to acquire the geographical features of the affected locations. This latter information was combined with environmental factors and clinical signs to form the set of independent variables affecting the outbreak of diseases. The neural network model outperformed the logistic regression, random forest, and gradient boosting methods in terms of predicting infection to estimate the probability of disease occurrence in farmed areas. Acute hepatopancreatic necrosis disease infected farms downstream of the Co Chien and Hau Rivers of Tra Vinh and west of Ca Mau. Enterocytozoon hepatopenaei infection is distributed in Soc Trang Province, while white spot syndrome virus has spread to the coastal districts of Soc Trang and Bac Lieu Provinces, where it is highly associated to water from a complex canal system.

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Post‐displacement community resilience: Considering the contribution of indigenous skills and cultural capital among ethnic minority Vietnamese          下载免费PDF全文

Jane Singer  Hai Hoang  Chiho Ochiai 《Asia Pacific viewpoint》2015,56(2):208-222

Despite an improving regulatory framework and policies governing compensation and resettlement, the majority of the millions displaced worldwide each year by hydropower dam construction continue to experience marginalisation and impoverishment, suggesting that external financial support must be supplemented by strengthened community‐based resilience. In order to understand more about the innate resources of displaced rural communities, we applied a community resilience approach to two resettled Co‐tu ethnic minority villages in an upland area in central Vietnam to identify their community capitals and their application in improving livelihoods and living conditions. We found that weak human and financial capital constrained the ability of the resettled residents to adopt new livelihoods or migrate to seek employment. Reduced forest and river access also problematised responses to a lack of agricultural land. However, traditionally strong village affinity and social networks were retained. In addition, indigenous skills such as housing construction, honed by a highly mobile traditional lifestyle, allowed residents to construct culturally significant structures like community houses and modify or augment received housing stock. These elements of social and cultural capital eased the process of post‐resettlement adaptation. We conclude that governments should reassess current resettlement policies that prioritise financial compensation and should incorporate awareness of the adaptive resilience and limitations fostered by indigenous knowledge and practices in resettlement action plans.  相似文献   

Between ‘state’ and ‘society’: Commune authorities and the environment in Vietnam's craft villages          下载免费PDF全文

Sango Mahanty  Trung Dinh Dang 《Asia Pacific viewpoint》2015,56(2):267-281

Maintaining a liveable environment in Vietnam's polluted craft villages is a daily challenge for state authorities and residents. Neighbouring urban populations demand that the state effectively curtails and manages pollution, while local residents prioritise their livelihoods and routinely flout regulations. The commune official, tasked with the seemingly impossible task of environmental regulation, occupies a fraught position, torn between the imperatives and constraints of craft producers and state regulatory demands. This study of water pollution in northern Vietnam's craft villages finds that commune officials' conflicted role in environmental governance is a central factor in the failure of the current environmental governance regime, and reflects the internally conflicted nature of the Vietnamese state.  相似文献   

A 50-year record of quinolone and sulphonamide antimicrobial agents in Seine River sediments     

Fatima Tamtam  Barbara Le Bot  Tuc Dinh  Sophie Mompelat  Joelle Eurin  Marc Chevreuil  Philippe Bonté  Jean-Marie Mouchel  Sophie Ayrault 《Journal of Soils and Sediments》2011,11(5):852-859

Purpose  

Even though sediments may represent a reservoir for antimicrobial agents, little is known about the persistence of these molecules over time or their accumulation. In this study, six antimicrobial agents, oxolinic acid, flumequine, nalidixic acid, norfloxacin, sulphamethoxazole and trimethoprim, were investigated in a sediment core from the Seine River. This work aimed to (1) measure antimicrobial agent contamination levels in the sediment and identify their origins, (2) obtain information on the persistence of these compounds in sediment over long periods (>4 years) and (3) show the existence of a historical record in sediment of river contamination by antimicrobial agents.  相似文献