78 research outputs found
Bio-economic evaluation and optimization of livestock intensification in the Central Highlands of Vietnam.
Beef cattle have high market demand in Vietnam and the Dak Lak local government encourages the development of beef value chains. Household surveys were carried out in Cu Jut and Ea Kar districts and farming systems and production specialization were found to differ in each district. Ea Kar farmers were more specialized in livestock production while Cu Jut farmers were more focused on cash crop production. The FarmDESIGN bio-economic model allowed us to study two representative farms, one from Ea Kar and one from Cu Jut district. The Ea Kar farm had a more integrated livestock production system, providing manure to the fields that produced feed for the livestock. Both farms had high farm-level nitrogen balances due to high feed and fertilizer imports. The soil organic matter (SOM) balance in Cu Jut was negative (-48 kg/ha) because of its manure management strategy. On both farms, the residues were removed from the fields, providing no input to SOM and were fed to livestock (Ea Kar) or burnt (CuJut). Livestock intensification scenarios that were implemented for the Ea Kar case study farm showed two possible pathways – forage-based and grain-based cattle fattening. Both strategies could lead to higher operating profits (+35% for forage-based cattle fattening and +59% for grain-based cattle fattening) and lower labor demands if they were skillfully implemented for the latter scenario. However, grain-based fattening negatively affected SOM balance, in contrast to forage-based fattening. The optimization of the current Ea Kar farm with FarmDESIGN indicated that there are options to change the farm setup in order to increase profitability and reduce family labor demands.
However there are some trade-offs to consider. If reducing environmental impact is a priority, there are alternative farm configurations that will produce lower greenhouse gas emissions while increasing SOM and increasing overall farm profitability. These should be assessed along with the farmers’ interests and priorities. Quantitative farm modeling of complex mixed farming systems can assess potential impact and support decision-making, targeting, prioritization and program design for sustainable intensification of livestock systems
Transformation of smallholder beef cattle production in Vietnam
This research describes and analyses how smallholder crop livestock farmers in rural Ea Kar, Vietnam, were able to take advantage of the rising demand for meat in urban centres and transform cattle production from a traditional, extensive grazing system to a more intensive, stall-fed system that supplied quality meat to urban markets. The traditional grazing system produced low-quality animals that could only be sold for local consumption. Introduction of the concept of farm-grown fodder production enabled farmers to produce fatter animals, achieving higher sale prices, and reduce labour inputs by moving from grazing to stall-feeding. These benefits convinced farmers, traders and local government that smallholder cattle production could be a viable enterprise and so stimulated stakeholder interest. Within 10 years, the way that cattle were produced and marketed changed considerably. By 2010, more than 3,000 smallholders had adopted farm-grown forages and stall-feeding, and many produced high-quality beef cattle. Traders had been able to develop access to urban markets as farmers were able to produce animals that satisfied the stringent quality requirements of urban markets. In addition to the underlying driver of strong market demand for quality meat, several factors contributed to this transition: (i) a convincing innovation – the use of farm-grown fodder – that provided immediate benefits to farmers and provided a vision for local stakeholders; (ii) a participatory, systems-oriented innovation process that emphasised capacity strengthening; (iii) a value chain approach that linked farmers and local traders to markets; (iv) the formation of a loosely structured coalition of local stakeholders that facilitated and managed the innovation process; and (v) technical support over a sufficiently long time period to allow innovation processes to become sustainable
Scaling BDD-based timed verification with simulation reduction
Digitization is a technique that has been widely used in real-time model checking. With the assumption of digital clocks, symbolic model checking techniques (like those based on BDDs) can be applied for real-time systems. The problem of model checking real-time systems based on digitization is that the number of tick transitions increases rapidly with the increment of clock upper bounds. In this paper, we propose to improve BDD-based verification for real-time systems using simulation reduction. We show that simulation reduction allows us to verify timed automata with large clock upper bounds and to converge faster to the fixpoint. The presented approach is applied to reachability and LTL verification for real-time systems. Finally, we compare our approach with existing tools such as Rabbit, Uppaal, and CTAV and show that our approach outperforms them and achieves a significant speedup.No Full Tex
Value chain assessment report for avocado, cattle, pepper and cassava in Dak Lak province of Central Highlands of Vietnam
Development and evaluation of a non-ribosomal random PCR and next-generation sequencing based assay for detection and sequencing of hand, foot and mouth disease pathogens
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Assessing the efficacy and safety of magnesium sulfate for management of autonomic nervous system dysregulation in Vietnamese children with severe hand foot and mouth disease.
BACKGROUND: Brainstem encephalitis is a serious complication of hand foot and mouth disease (HFMD) in children. Autonomic nervous system (ANS) dysregulation and hypertension may occur, sometimes progressing to cardiopulmonary failure and death. Vietnamese national guidelines recommend use of milrinone if ANS dysregulation with Stage 2 hypertension develops. We wished to investigate whether magnesium sulfate (MgSO4) improved outcomes in children with HFMD if used earlier in the evolution of the ANS dysregulation (Stage 1 hypertension). METHODS: During a regional epidemic we conducted a randomized, double-blind, placebo-controlled trial of MgSO4 in children with HFMD, ANS dysregulation and Stage 1 hypertension, at the Hospital for Tropical Diseases in Ho Chi Minh city. Study participants received an infusion of MgSO4 or matched placebo for 72 h. We also reviewed data from non-trial HFMD patients in whom milrinone failed to control hypertension, some of whom received MgSO4 as second line therapy. The primary outcome for both analyses was a composite of disease progression within 72 h - addition of milrinone (trial participants only), need for ventilation, shock, or death. RESULTS: Between June 2014 and September 2016, 14 and 12 participants received MgSO4 or placebo respectively, before the trial was stopped due to futility. Among 45 non-trial cases with poorly controlled hypertension despite high-dose milrinone, 33 received MgSO4 while 12 did not. There were no statistically significant differences in the composite outcome between the MgSO4 and the placebo/control groups in either study (adjusted relative risk (95%CI) of [6/14 (43%) vs. 6/12 (50%)], 0.84 (0.37, 1.92), p = 0.682 in the trial and [1/33 (3%) vs. 2/12 (17%)], 0.16 (0.01, 1.79), p = 0.132 in the observational cohort). The incidence of adverse events was similar between the groups. Potentially toxic magnesium levels occurred very rarely with the infusion regime used. CONCLUSION: Although we could not demonstrate efficacy in these studies, there were no safety signals associated with use of 30-50 mg/kg/hr. MgSO4 in severe HFMD. Intermittent outbreaks of HFMD are likely to continue across the region, and an adequately powered trial is still needed to evaluate use of MgSO4 in controlling hypertension in severe HFMD, potentially involving a higher dose regimen. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01940250 (Registered 22 AUG 2013). Trial sponsor: University of Oxford
TextANIMAR: Text-based 3D Animal Fine-Grained Retrieval
3D object retrieval is an important yet challenging task, which has drawn
more and more attention in recent years. While existing approaches have made
strides in addressing this issue, they are often limited to restricted settings
such as image and sketch queries, which are often unfriendly interactions for
common users. In order to overcome these limitations, this paper presents a
novel SHREC challenge track focusing on text-based fine-grained retrieval of 3D
animal models. Unlike previous SHREC challenge tracks, the proposed task is
considerably more challenging, requiring participants to develop innovative
approaches to tackle the problem of text-based retrieval. Despite the increased
difficulty, we believe that this task has the potential to drive useful
applications in practice and facilitate more intuitive interactions with 3D
objects. Five groups participated in our competition, submitting a total of 114
runs. While the results obtained in our competition are satisfactory, we note
that the challenges presented by this task are far from being fully solved. As
such, we provide insights into potential areas for future research and
improvements. We believe that we can help push the boundaries of 3D object
retrieval and facilitate more user-friendly interactions via vision-language
technologies.Comment: arXiv admin note: text overlap with arXiv:2304.0573
Viral Etiology of Encephalitis in Children in Southern Vietnam: Results of a One-Year Prospective Descriptive Study
Viral encephalitis is associated with high morbidity and mortality in Vietnam. However little is known about the causes of the disease due to a lack of diagnostic facilities in this relatively resource-poor setting. Knowledge about the etiologies and clinical outcome of viral encephalitis is necessary for future design of intervention studies targeted at improvement of clinical management, treatment and prevention of the disease. We report the viral agents, clinical outcome and prognostic factors of mortality of encephalitis in children admitted to a referral hospital for children in southern Vietnam. We show that about one third of the enrolled patients die acutely, and that mortality is independently associated with patient age and Glasgow Coma Scale on admission. Japanese encephalitis, dengue virus and enterovirus (including enterovirus 71) are the major viruses detected in our patients. However, more than half of the patients remain undiagnosed, while mortality in this group is as high as in the diagnosed group. This study will benefit clinicians and public health in terms of clinical management and prevention of childhood encephalitis in Vietnam
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