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Whiteleg shrimp (Litopenaeus vannamei) is now the main species cultivated in various geographic locations. Whiteleg shrimp have a wide range of salinity tolerance, but a matter of deficiency of minerals and trace elements need to be taken care of when shrimp are grown in low saline area. It may induce higher mortality and slower growth performances of shrimp. Two stages of shrimp juveniles were subsequently tested with different formulae of a liquid nutraceutical of essential minerals and trace elements. Each stage was performed in a 28-day trial with follow-up parameters of shrimp growth indices and environmental changes throughout the tests. The use of mineral supplementation in whiteleg shrimp diet in low salinity area significantly increased growth performance, survival rate and color intensity. This study has demonstrated the efficacy of a liquid form of mineral supplement product administered by top-coating onto the feed to shrimp during 4 weeks of grow-out at 5‰ salinity, but the application was dependent on formula and dose. Further research on application regime using this liquid mineral product should be performed to optimize a protocol for a whole culture crop as different stages of shrimp may require different supplementation doses.

This letter proposes improved pilot designs to enhance the connectivity of multicarrier massive MIMO systems. Exploiting the fact that orthogonal frequency-division multiplexing (OFDM) training symbols end with zero samples, the proposed pilot designs reduce pilot overhead by truncating the zero samples and/or intentionally using them for a guard interval without affecting the channel estimation quality. The proposed designs allow a massive MIMO system either to serve more users with a fixed amount of training time, or requires less training time for a fixed number of users. Numerical results obtained for a cell-free massive MIMO system (as an application use case) demonstrate significant improvements in connectivity and spectral efficiency by the proposed designs over the conventional designs.

Oil spillage is one of the world’s biggest environmental problems, its various impacts including shifting the balance of the ecosystem, affecting marine animals, and inhibiting economical activities. Therefore, the efficient resolution of this issue is a topic of great interest. In this work, the solution of choice is an adsorption method using aerogels made from coconut peat. Cellulose coconut peat aerogels (CCPA) are synthesized by cross-linking method with poly(vinyl alcohol) (PVA) and freeze-drying technique to form the porous structure. The CCPA are furthermore dip-coated in poly(dimethylsiloxane) (PDMS) to obtain PDMS-coated cellulose coconut peat aerogel (CCPA-P) with hydrophobic properties for the studying of oil adsorption. The characteristics of CCPA and CCPA-P are evaluated by density and porosity, specific surface area following Brunauer-Emmett-Teller (BET) theory, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), and water contact angle (WCA) measurements. Results showed that CCPA-10 with the mass ratios of cellulose to PVA 10:1 had the lowest density of 28.21 mg/cm3, highest porosity of 98.15 %. Furthermore, the modified CCPA-P10 had maximum adsorption capacity of up to 2.083 and 2.452 mg/mg for the static adsorption model and dynamic adsorption model, respectively. This indicates that coconut peat is a viable material for aerogel synthesis in oil adsorption applications.

Discordant results of recombinant protein-based enzyme-linked immunosorbent assays (ELISA) and other antigen detection tests are a common and vexing problem in scientific research and clinical laboratories. The reproducibility of immunoassays based on antibody specificity can be adversely affected by cryptic changes in the composition of the analyte (e.g., the protein antigen). By use of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometry analyses, we found varying levels of purity and the extent of post-translational modifications (PTMs), particularly of N-linked glycosylation and phosphorylation, among varied lots of recombinant glucose-regulated protein 78 (GRP78) expressed in Escherichia coli. We expect these lotto-lot variabilities of both purity and PTMs led to inconsistent results stemming from ELISA assays that measured GRP78 autoantibody levels in patient plasma specimens. We present these analyses to draw readers’ attention to a potentially common, yet seldom appreciated problem, in laboratory assays using recombinant proteins as antigens for antibody detection, and propose a workflow to detect and troubleshoot for this typical problem.

© 1967-2012 IEEE. This paper studies the uplink (UL) transmission of a generalized cell-free massive multiple-input multiple-output (massive MIMO) system in which multiple base stations (or access points), each equipped with a multiple-antenna array and connected to a central processing unit (CPU) over a backhaul network, simultaneously serve multiple users in a cell-free service area. The paper focuses on the non-orthogonal multiple access (NOMA) approach for sharing pilot sequences among users. Unlike the conventional cell-free massive MIMO-NOMA systems in which the UL signals from different access points are equally combined over the backhaul network, this paper first develops an optimal backhaul combining (OBC) method to maximize the UL signal-to-interference-plus-noise ratio (SINR). It is shown that, by using OBC, the correlated interference can be effectively mitigated if the number of users assigned to each pilot sequence is less than or equal to the number of base stations (BSs). As a result, the cell-free massive MIMO-NOMA system with OBC can enjoy unlimited performance when the number of antennas at each BS tends to infinity. A closed-form SINR expression is derived under Rayleigh fading and used to formulate a max-min quality-of-service (QoS) power control problem to further enhance the system performance. To deal with the NP-hardness of the concerned optimization problem, a successive inner approximation technique is applied to convert the original problem into a series of convex optimizations, which can be solved iteratively. In addition, a user grouping algorithm is also developed and shown to be better than random user grouping and a grouping method recently proposed in the literature. Numerical results are presented to corroborate the analysis and demonstrate the superiority of the proposed optimal backhaul combining over both equal-gain backhaul combining and zero-forcing backhaul combining.

ObjectiveWe characterised the clinical course, treatment and outcomes in 59 patients with relapsing myelin oligodendrocyte glycoprotein (MOG) antibody-associated demyelination.MethodsWe evaluated clinical phenotypes, annualised relapse rates (ARR) prior and on immunotherapy and Expanded Disability Status Scale (EDSS), in 218 demyelinating episodes from 33 paediatric and 26 adult patients.ResultsThe most common initial presentation in the cohort was optic neuritis (ON) in 54% (bilateral (BON) 32%, unilateral (UON) 22%), followed by acute disseminated encephalomyelitis (ADEM) (20%), which occurred exclusively in children. ON was the dominant phenotype (UON 35%, BON 19%) of all clinical episodes. 109/226 (48%) MRIs had no brain lesions. Patients were steroid responsive, but 70% of episodes treated with oral prednisone relapsed, particularly at doses ConclusionRelapsing MOG antibody-associated demyelination is strongly associated with ON across all age groups and ADEM in children. Patients are highly responsive to steroids, but vulnerable to relapse on steroid reduction and cessation.

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim There has been increasing interest in electronic systems with integrated microfluidic active cooling modules. However, the failure of 3C-SiC/Si interface with increasing temperature has prevented the development of 3C-SiC power electronic devices. Here, all integrated transparent heating, sensing, and cooling systems are developed on a single silicon carbide (SiC) chip for efficient thermal management. SiC nanofilms are grown on a silicon wafer, are transferred to a glass substrate, and then a micro electromechanical system process is employed to fabricate a SiC-on-glass system with integrated heaters and temperature sensors. A cooling system is fabricated with microchannel using 3D printing, molding, and plasma assisted bonding. The thermal management of the SiC-based system shows an excellent capability of heating and detecting temperature as well as effective cooling with an efficiency of from 0.24 to 0.28 and a maximum cooling rate of 0.1 K(µL min−1)−1. The fabrication strategy can be utilized for large production of SiC power nanoelectronics with high efficiency of integrated thermal management systems.

Population ageing is rapidly becoming a global issue and will have a major impact on health policies and programmes. The World Health Organization's Study on global AGEing and adult health (SAGE) aims to address the gap in reliable data and scientific knowledge on ageing and health in low- and middle-income countries. SAGE is a longitudinal study with nationally representative samples of persons aged 50+ years in China, Ghana, India, Mexico, Russia and South Africa, with a smaller sample of adults aged 18-49 years in each country for comparisons. Instruments are compatible with other large high-income country longitudinal ageing studies. Wave 1 was conducted during 2007-2010 and included a total of 34 124 respondents aged 50+ and 8340 aged 18-49. In four countries, a subsample consisting of 8160 respondents participated in Wave 1 and the 2002/04 World Health Survey (referred to as SAGE Wave 0). Wave 2 data collection will start in 2012/13, following up all Wave 1 respondents. Wave 3 is planned for 2014/15. SAGE is committed to the public release of study instruments, protocols and meta- and micro-data: access is provided upon completion of a Users Agreement available through WHO's SAGE website (www.who.int/healthinfo/systems/sage) and WHO's archive using the National Data Archive application (http://apps.who.int/healthinfo/systems/surveydata)

Part of clinically applicable bone graft substitutes are developed by using mechanical stimulation of flow-perfusion into cell-seeded scaffolds. The role of fluid flow is crucial in driving the nutrient to seeded cells and in stimulating cell colonization. A common numerical approach is to use a multiscale model to link some physical quantities (wall shear stress and inlet flow rate) that act at different scales. In this study, a multiscale model is developed in order to determine the optimal inlet flow rate to cultivate osteoblast-like cells seeded in a controlled macroporous biomaterial inside a perfusion bioreactor system. We focus particularly on the influence of Wall Shear Stress on cell colonization to predict cell colonization at the macroscale. Results obtained at the microscale are interpolated at the macroscale to determine the optimal flow rate. For a macroporous scaffold made of interconnected pores with pore diameters of above 350 μ m and interconnection diameters of 150 μ m , the model predicts a cell colonization of 325% after a 7-day-cell culture with a constant inlet flow rate of 0.69 m L · m i n − 1 . Furthermore, the strength of this protocol is the possibility to adapt it to most porous biomaterials and dynamic cell culture systems.

Introduction: Antiviral resistance has been reported in seasonal influenza A viruses and avian influenza A(H5N1) viruses in Viet Nam, raising concerns about the efficacy of treatment. Methods: We analysed specimens from two sources during the period 2009–2012: influenza-positive samples from influenza-like illness patients at sentinel clinics in northern Viet Nam and isolates from patients with confirmed A(H5N1) infections. Pyrosequencing was used to detect mutations: H275Y [for A(H1N1) and A(H5N1)], E119V [for A(H3N2)] and I117V [for A(H5N1)]. A neuraminidase inhibition assay was used to determine the Inhibitory Concentration 50 (IC50) values for all influenza A and B isolates. Results: There were 341 influenza A positive samples identified; influenza A(H1N1)pdm09 was identified most frequently (n = 215). In 2009, oseltamivir resistance was observed in 100% (19 of 19) of seasonal A(H1N1) isolates and 1.4% (3/215) of A(H1N1)pdm09 isolates. This H275Y mutation was not found in influenza subtypes A(H5N1) or A(H3N2) isolates. Discussion: In Viet Nam, seasonal and A(H5N1) influenza vaccines are not currently available; thus, effective treatment is required. The presence of oseltamivir-resistant viruses is therefore a concern. Active surveillance for oseltamivir resistance among influenza viruses circulating in Viet Nam should be continued.

Background Streptococcus pneumoniae is the most significant bacterial cause of community-acquired pneumonia among children under five years worldwide. Updated resistance information of S. pneumoniae among children is essential to adjust the recommendations for empirical treatment of community-acquired pneumonia, which will have immense implications for local and global health. This study investigated the prevalence of antibiotic resistance in isolated strains of S. pneumoniae and relationship with antibiotic use and demographic factors of children under five in rural Vietnam in 2007. Methods In Bavi district, 847 children 6 to 60 months were selected from 847 households. The main child-caregivers in the households were interviewed weekly using structured questionnaires to collect information of daily illness symptoms and drug use for the selected child over a four-week period (from March through June 2007). In the 3rd week, the children were invited for a clinical examination and to collect nasopharyngeal samples for S. pneumoniae identification. Etest and disk diffusion were used to test antibiotic susceptibility. Results Of 818 participating children, 258 (32%) had ongoing respiratory infections, 421 (52%) carried S. pneumoniae, and 477 (58%) had used antibiotics within the previous three weeks. Of the 421 isolates, 95% were resistant to at least one antibiotic (401/421). Resistance to co-trimoxazole, tetracycline, phenoxymethylpenicillin, erythromycin and ciprofloxacin was 78%, 75%, 75%, 70% and 28%, respectively. Low resistance was noted for amoxicillin (4%), benzylpenicillin (4%), and cefotaxime (2%). The intermediate resistance to amoxicillin was 32%. Multidrug-resistance was seen in 60%. The most common pattern was co-resistance to co-trimoxazole, tetracycline and erythromycin. The proportion of children carrying resistant bacteria was higher among the children who had used antibiotics in the previous three weeks. Conclusions Resistance to commonly used antibiotics and multidrug-resistance of S. pneumoniae in the area is remarkably high. High-dose amoxicillin is the only investigated oral antibiotic that can possibly be used for treatment of community-acquired pneumococcal infections. Strategies to promote appropriate prescribing and dispensing of effective antibiotics should be immediately implemented for the benefit of local and global health.

Vietnam has experienced rapid economic growth following the transition, which began in the mid 1980s, from a planned agriculture based economy to a more market orientated one. In this paper, the associations between socioeconomic variables and mortality for 41,000 adults in Northern Vietnam followed from January 1999 to March 2008 are estimated using Cox's proportionally hazard models. Also, we use decomposition techniques to investigate the relative importance of socioeconomic factors for explaining inequality in age-standardized mortality risk. The results confirm previously found negative associations between mortality and income and education, for both men and women. We also found that marital status, at least for men, explain a large and growing part of the inequality. Finally, estimation results for relative education variables suggest that there exist positive spillover effects of education, meaning that higher education of one's neighbors or spouse might reduce ones mortality risk.

One of the problems in drinking water that raises concern over the world is that millions of people still have to use arsenic-contaminated water. There is a worldwide need to develop appropriate technologies to remove arsenic from water for household and community water supply systems. In this study, a new material namely iron oxide coated sponge (IOCSp) was developed and used to remove arsenic (As) from contaminated groundwater in Vietnam. The results indicated that lOCSp has a high capacity in removing both As (V) and As (III). The adsorption capacity of IOCSp was up to 4.6 mg As/g IOCSp, showing better than many other materials. It was observed from a pilot study that a small quantity of IOCSp (180 g) could reduce As concentration of 480 μg/L in 1.5 m3 of contaminated natural water to below 40 μg/L. In addition, an exhausted IOCSp, containing a large amount of arsenic (up to 0.42 wt %) could safely be disposed through the solidification/stabilization with cement. Addition of fly ash also reduced the amount of arsenic in the leachate. © IWA Publishing 2009.

Background The inequity caused by health financing in Vietnam, which mainly relies on out-of-pocket payments, has put pre-payment reform high on the political agenda. This paper reports on a study of the willingness to pay for health insurance among a rural population in northern Vietnam, exploring whether the Vietnamese are willing to pay enough to sufficiently finance a health insurance system. Methods Using the Epidemiological Field Laboratory for Health Systems Research in the Bavi district (FilaBavi), 2070 households were randomly selected for the study. Existing FilaBavi interviewers were trained especially for this study. The interview questionnaire was developed through a pilot study followed by focus group discussions among interviewers. Determinants of households' willingness to pay were studied through interval regression by which problems such as zero answers, skewness, outliers and the heaping effect may be solved. Results Households' average willingness to pay (WTP) is higher than their costs for public health care and self-treatment. For 70–80% of the respondents, average WTP is also sufficient to pay the lower range of premiums in existing health insurance programmes. However, the average WTP would only be sufficient to finance about half of total household public, as well as private, health care costs. Variables that reflect income, health care need, age and educational level were significant determinants of households' willingness to pay. Contrary to expectations, age was negatively related to willingness to pay. Conclusion Since WTP is sufficient to cover household costs for public health care, it depends to what extent households would substitute private for public care and increase utilization as to whether WTP would also be sufficient enough to finance health insurance. This study highlights potential for public information schemes that may change the negative attitude towards health insurance, which this study has uncovered. A key task for policy makers is to win the trust of the population in relation to a health insurance system, particularly among the old and those with relatively low education.

Objetivo: Investigar la práctica auto-comunicada y la práctica real del personal de las farmacias privadas en relación a la regulación sobre medicamentos y provisión de prednisolona (un corticoide de prescripción) solicitado para tratar un dolor lumbar. Método: Se seleccionaron aleatoriamente sesenta farmacias privadas en Hanoi. Se evaluó la práctica auto-comunicada a través de entrevistas con el personal de la farmacia mediante un cuestionario; la práctica real fue evaluada con el método del Cliente Simulado con 5 visitas a cada farmacia (un total de 295 visitas). Resultados: El sesenta por ciento del personal de farmacia entrevistado dijo que no dispensaría corticoides sin receta, y el 60% pudo mencionar algunos de los efectos adversos. En la práctica, todas menos una farmacia dispensaron corticoides sin receta en el 76% de las visitas. Las preguntas y los consejos dados a los clientes se asociaron con significativamente menor dispensación de corticoides. Conclusión: El bajo cumplimiento con las regulaciones y la discrepancia entre práctica declarada y práctica real produce preocupación. Este estudio indica que las presiones comerciales exceden al efecto preventivo de las regulaciones sobre medicamentos y su implantación y por tanto es necesario mejorar la vigilancia de las regulaciones.