39 research outputs found
Simulation of non‑dilute fibre suspensions using RBF‑based macro–micro multiscale method
The multiscale stochastic simulation method based on the marriage of the Brownian Configuration Field (BCF) and the Radial Basis Function mesh-free approximation for dilute fibre suspensions by our group, is further developed to simulate non-dilute fibre suspensions. For the present approach, the macro and micro processes proceeded at each time step are linked to each other by a fibre contributed stress formula associated with the used kinetic model. Due to the feature of non-dilute fibre suspensions, the interaction between fibres is introduced into the evolution equation to determine fibre configurations using the BCF method. The fibre stresses are then determined based on the fibre configuration fields using the Phan–Thien–Graham model. The efficiency of the simulation method is demonstrated by the analysis of the two challenging problems, the axisymmetric contraction and expansion flows, for a range of the fibre concentration from semi-dilute to concentrated regimes. Results evidenced by numerical experiments show that the present method would be potential in analysing and simulating various suspensions in food and medical industries
Study on association between SLC2A9 rs3733591 and Gout susceptibility in 481 Vietnamese individuals
Gout is a common form of inflammatory arthritis that is strongly associated with elevated uric acid concentration in the blood. The development of the disease is not only triggered by environmental factors but also genetic variations. Previous studies demonstrated that the genetic associations with gout vary in different populations in the world. This study aimed to identify the relationship between SLC2A9 rs3733591 and gout susceptibility in the Vietnamese population. Total DNAs were extracted from 481 blood samples including 160 patients with gout and 321 age-matched healthy controls. The genotyping of SLC2A9 rs3733591 was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Chi-squared test was used to test whether the genotypes frequencies of rs3733591 follow Hardy-Weinberg equilibrium (HWE) and to check its association with gout in three models (additive, recessive, dominant) and allele form. The result showed that SLC2A9 rs3733591 was in agreement with Hardy-Weinberg equilibrium (p>0.05). However, there was no association between the rs3733591 and gout in any tested models (p>0.05). This study will contribute to the genetic study of gout susceptibility in Vietnam
Computation of limit and shakedown using the NS-FEM and second-order cone programming
This paper presents a novel numerical procedure for computation of limit and shakedown using node-based smoothed finite element method (NS-FEM) in combination with second-order cone programming (SOCP). The obtained discretization formulation is then cast in a form which involves second-order cone constraints, ensuring that the underlying optimization problem can be solved by highly efficient primal-dual interior point algorithm. Furthermore, in the NS-FEM, the system stiffness matrix is computed using the smoothed strains over the smoothing domains associated with nodes. This ensures that the size of the resulting optimization problem is kept to a minimum. The efficiency of the present approach is illustrated by examining several numerical examples
Saprochaete Capitata Infection in an 80–Year Old Chronic Obstructive Pulmonary Disease (COPD) Patient: A Case Report
BACKGROUND: The fungal disease caused by invasive fungus Saprochaete capitata is becoming an increasingly popular infection. Fungal pathogens mainly occur in patients with immunocompromised disorders such as hematologic malignancies, acute myeloid leukemia, transplant patients.
CASE REPORT: In this study, we presented a COPD patient infected with S. capitata. At the first check, the patient showed cough, dyspnea, chest pain on both sides. The clinical laboratory test result was characterized with high White blood cell (12.8 G/L), HIV negative. The X ray showed bronchitis and emphysema. Bronchoscopy illustrated bronchial mucositis. CT scanner demonstrated pneumonia with fuzzy nodular lesions and thick interstitial organization in both lungs. The patient was treated with ciprofloxacin 800 mg/day; cefuroxime 2250 mmg/day. However, the fever appeared 2 weeks thereafter. The S. capitata was discovered in the bronchial fluid. The patient was then treated with fluconazole 400 mg/day for 14 days. At the end of treatment, all signs and symptoms of S. capitata infection disappeared and the patient recovered.
CONCLUSION: This case study showed that S. capitata infection can occur in the COPD patients and fluconazole is a pertinent drug for treatment of the infection
Current status of fish-borne zoonotic trematode infections in Gia Vien district, Ninh Binh province, Vietnam
BACKGROUND: Ninh Binh province is known as an endemic area of fish-borne zoonotic trematode (FZT) transmission in Vietnam. A cross-sectional study was conducted in Gia Minh and Gia Thinh communes of Gia Vien district, Ninh Binh province to investigate the infections with different stages of FZT in various host species. METHODS: Faecal samples from 1,857 humans were examined for trematode eggs using the Kato-Katz method, while faecal samples from 104 dogs, 100 cats, and 100 pigs were examined using the Formalin-ethyl acetate concentration technique (FECT). A total of 483 specimens of freshwater fish, representing 9 species, were examined for metacercariae using the artificial digestion method. Three methods of cercarial detection (shedding, crushing and cutting) were applied for examination of 3,972 specimens of freshwater snails, representing 7 species. All relevant data e.g. location, sex, age group, animal species, and habitat were recorded for statistical analyses. RESULTS: Helminth eggs were found in 65.5% of the human faecal samples, including 20.5% of faecal samples containing small trematode eggs. Infection with small trematodes differed among communes, age groups and sexes. Eggs of small trematodes were found in 32.7% of faecal samples from dogs, 49.0% from cats and 13.0% from pigs. The difference in prevalences and intensities were significant among species of animals but did not differ between the two communes. All fish species were infected with FZT, with an average prevalence of 56.1% and a mean intensity of 33.245 metacercariae per gram. Prevalence and intensity in fish differed significantly among cummunes and fish groups. Six species of zoonotic trematodes were identified. Metacercariae of the small liver fluke, Clonorchis sinensis, was only found in Hemiculter leucisculus. A total of 9 specimens from two snail species, Melanoides tuberculata and Bithynia fuchsiana, were infected with trematodes and four cercarial types were detected in the study sites. CONCLUSIONS: We conclude that Gia Minh and Gia Thinh communes are continuing to be hot-spot endemic areas of FZT and other helminths infections where the habit of eating raw fish by the local people is still present
From “weak” to “strong” sustainability:protesting for environmental justice in Vietnam
Lean Concept in Fashion and Textile Manufacturing
The concept of “lean manufacturing” refers to a process of manufacturing, starting from raw materials until the delivery of the finished goods to the end-users, with prudent management of resources resulting in monetary and time savings. Lean principles have helped fashion and textile firms become more competitive and sustainable. Lean manufacturing has minimized waste and in turn reduced costs by applying reforms introduced by “Toyota” in the 1990s, and from which the technical term “lean” was derived and became popular. This chapter discusses the benefits and challenges of key lean principles in the fashion and textile industry from product, process design and supply chain perspectives using lean operations. Modular design and postponement are two major lean operations that have had a significant impact on the fashion and textile industry. The literature and real case information from the most prominent fashion retailers, Zara, Benetton and H&M, have been used to illustrate lean applications and their implications for the fashion and textile industry
An auto-inducible phosphate-controlled expression system of Bacillus licheniformis
Abstract Background A promoter that drives high-level, long-term expression of the target gene under substrate limited growth conditions in the absence of an artificial inducer would facilitate the efficient production of heterologous proteins at low cost. A novel phosphate-regulated expression system was constructed using the promoter of the phytase encoding gene phyL from Bacillus licheniformis for the overexpression of proteins in this industrially relevant host. Results It is shown that the phyL promoter enables a strong overexpression of the heterologous genes amyE and xynA in B. licheniformis when cells were subjected to phosphate limitation. Whether B. licheniformis can use phytate as an alternative phosphate source and how this substrate influences the PphyL controlled gene expression under growth conditions with limited inorganic phosphate concentrations were also investigated. It is shown that B. licheniformis cells are able to use sodium phytate as alternative phosphate source. The addition of small amounts of sodium phytate (≤ 5 mM) to the growth medium resulted in a strong induction and overexpression of both model genes in B. licheniformis cells under phosphate limited growth conditions. Conclusions The PphyL controlled expression of the investigated heterologous genes in B. licheniformis is strongly auto-induced under phosphate limited conditions. The proposed PphyL expression system enables an overexpression of target genes in B. licheniformis under growth conditions, which can be easily performed in a fed-batch fermentation process
Plastic collapse analysis of cracked structures using extended isogeometric elements and second-order cone programming
Dynamic maintenance grouping and routing for geographically dispersed production systems
International audienceThis paper presents a dynamic grouping and routing approach for the maintenance optimization of a geographically dispersed production system (GDPS) consisting of several production sites located far apart from each other. Only one maintenance center is in charge of the preventive maintenance of the system. Maintenance grouping and routing are two interrelated processes but often investigated separately in literature. In this paper, these two processes are jointly studied and integrated in a global model considering economic and geographical dependencies at both component and site levels. The optimal maintenance grouped plan and routes are then determined by a combination of the Local Search Genetic Algorithm (LSGA) and Branch and Bound method (BAB). Moreover, several dynamic contexts impacting the current optimal maintenance grouped planning and routing, which may occur with time, are also studied and integrated in the joint optimization process. Thanks to this consideration, the proposed approach allows updating the grouped maintenance planning and routing to take into account the impacts of dynamic contexts when they occur. The uses and advantages of the proposed approach are illustrated through a numerical example of a GDPS consisting of 15 components located in five different sites