36 research outputs found
Meteorological Drought Forecasting Based on Climate Signals Using Artificial Neural Network â A Case Study in Khanhhoa Province Vietnam
AbstractIn Khanhhoa Province (Vietnam) long-lasting droughts often occur, causing negative consequences for this region, so accurate drought forecasting is of paramount importance. Normally, drought index forecasting model uses previously lagged observations of the index itself and rainfall as input variables. Recently, climate signals are being also used as potential predictors. In this study, we use 3-month, 6-month, and 12-month of Standardized Precipitation Evapotranspiration Index (SPEI), with a calculation time during the period from 1977 to 2014. This paper aims at examining the lagged climate signals to predict SPEI at Khanhhoa province, using artificial neural network. Climate signals indices from Indian Ocean and Pacific Ocean surrounding study area were analysed to select five predictors for the model. These were combined with local variables (lagged SPEI and rainfall) and used as input variables in 16 different models for different forecast horizons. The results show that adding climate signals can achieve better prediction. Climate signals can be also used solely as predictors without using local variables â in this case they explain the variation SPEI (longer horizons, e.g.12-month) reaching 61 â 80%. The developed model can benefit developing long-term policies for reservoir and irrigation regulation and plant alternation schemes in the context of drought hazard
Isolation and characterization of chlorpyrifos-degrading bacteria in tea-growing soils
The excess use of pesticides in the agricultural sector has caused environmental pollution and affected the complete ecosystem. Among the various commonly used pesticides, chlorpyrifos (CPF) is widely used against multiple agrarian pests due to its effectiveness and higher insecticidal activities. However, along with its beneficial usage, CPF has various residual effects on the environment, causing multiple negative impacts on aquatic organisms and human health. Consequently, methods for eliminating CPF in the background are essential. Among the currently available approaches to CPF remediation, biological methods using microorganisms are eco-friendly and cost-effective. Therefore, this study was conducted to isolate and characterize chlorpyrifos-degrading bacteria from the tea-growing soil of Vietnam. For this, soil samples were collected from the 20 tea-growing areas of Vietnam. From the collected samples, three bacterial strains viz., Methylobacterium populi CNN2, Ensifer adhaerens VNN3, and Acinetobacter pittii CNN4 have been isolated by using streak plate method and identified based on 16S rRNA gene analysis. The study results showed that under laboratory conditions, E. adhaerens VNN3 had the highest CPF degradation ability and was followed by the strain M. populi CNN2. In liquid medium, CPF concentration (100 mg/L) was reduced by 95.2% and 81.4% by E.adhaerens VNN3 and M. populi CNN2, respectively, after 72 h. Further, under in-vitro conditions, the concentration of CPF was reduced from 500 mg/kg to 112 ± 1.73 (77.6%) and 197 ± 2.08 mg/kg (60.6%) by E. adhaerens VNN3 and M. populi CNN2, respectively. Based on the obtained results, it can be concluded that E. adhaerens VNN3 and M. populi CNN2 can be used for CPF-contaminated agricultural soil remediation
Synthesis and characterization of MCM-41 containing CeO2
MCM-41 and cerium containing MCM-41 mesoporous materials were obtained by hydrothermal method under atmospheric pressure (the molar ratio SiO2/CeO2= x, x = 160, 80, 40, 20). The characteristics of all samples were investigated by ThermoGravimetric - Differential Thermal Analysis (TG-DTA), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray spectrometry (EDX) and nitrogen adsorption-desorption isotherms. The results indicated that: particles are sphere, uniform and pore size is about 50 nm; the pore systems are hexagonal structure, ordered arrangement; the samples have high surface area ( 600 m2/g) with narrow pore size distribution curve. Results of EDX showed that the SiO2/CeO2molar ratios of samples were very similar to the molar ratios in gel
Characterization of arsenic-resistant endophytic Priestia megaterium R2.5.2 isolated from ferns in an arsenic-contaminated multi-metal mine in Vietnam
Bioremediation is a biological process to remove or neutralize environmental pollutants. This study was carried out to investing at the efficacy of arsenic resistant endophytic bacteria isolated from Pteris vittata, Pityrogramma calomelanos, Blenchum orientale, and Nephrolepis exaltata, which grow in a highly arsenic (As) contamination mining site in Vietnam. Their segmented roots, stems, and leaves were homogenized separately and inoculated on LB agar plates containing 5mM As(III) and As(V). A total of 31 arsenic resistant endophytic strains were selected, in which strain R2.5.2 isolated from the root of P. calomelanos had the highest arsenic resistant capability. Strain R2.5.2 tolerated up to 320 mM and 160 mM of arsenate and arsenite, respectively. The strain developed well on a media of 0.1 5% NaCl, at 20-40ÂșC and pH 5 9, and actively utilized most of the sugar sources. It had a high IAA biosynthesis capacity with an average concentration of 19.14 mg/L, tolerated to 0.5-16 mM concentration of Ag+, Hg2+, Co2+, Ni2+, Cu2+, Cr4+, and reduced As(V). Based on 16s rDNA, R2.5.2 was identified as Priestia megaterium. The ars C gene coding for arsenate reductase catalyzing reduction of As(V) was successfully amplified in P. megaterium R2.5.2. The selected strain may have potential use for bioremediation practice
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
Wilmsâ Tumor in Horseshoe Kidney
Wilmsâ tumor is the most common malignant kidney tumor found in children. The Horseshoe kidney is the most common renal fusion malformation. However, Wilmsâ tumor is rarely identified in horseshoe kidney patients. Multimodal treatments in Wilmsâ tumor can play important roles in increasing the survival rate. In this study, we report the case of a 6-year-old boy in whom a Wilmsâ tumor was identified in a horseshoe kidney. The tumor was successfully treated with preoperative chemotherapy, followed by surgical resection
Social norms and political constructions of drug use: A narrative story of Vietnam
Situated close to the Golden Triangle region, and lying across important South-East Asian region traffic routes, Vietnam has a long history of drug use. The negative attitudes among Vietnamese people towards drug use have emerged from the past actions of colonial governments and recently been influenced by social media and political factors. Yet the reality of drug use is more complex, and it is essential to move beyond the overly simple axiom that drug use causes addiction and crime. Combining historical narratives and grey literature, this paper argues that drug use has been politically and socially constructed in Vietnam rather than based on evidence or rationale. Moving forward on harm reduction in drug policy, Vietnam should need more specific actions with its clear plans to at least support drug users during and post detoxication in voluntary communityâs models as well as methadone maintenance treatment rather than in compulsory treatment centres
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A Cluster Randomized Controlled Trial of a Lay Health Worker Intervention to Increase Healthy Eating and Physical Activity Among Vietnamese Americans.
IntroductionAmericans have low levels of knowledge of and adherence to recommendations for healthy eating of fruits and vegetables and for physical activity (HEPA). We conducted a cluster randomized controlled trial of a lay health worker intervention to increase HEPA among Vietnamese Americans.MethodsWe randomized 64 lay health workers to 2 intervention arms. Each lay health worker recruited 10 participants aged 50 to 74. From 2008 to 2013, using flip charts, lay health workers led 2 educational sessions on HEPA (intervention) or colorectal cancer (comparison). We assessed HEPA knowledge and self-reported behaviors by preintervention and postintervention surveys 6 months apart.ResultsOf the 640 participants, 50.0% were female, 38.4% had lived in the United States for 10 years or fewer, and 71.4% reported limited English proficiency. Knowledge of the recommended intake of fruits and vegetables (â„5 servings daily) increased from 2.6% to 60.5% in the intervention group (n = 311) and from 2.9% to 6.7% in the comparison group (n = 316) (intervention vs comparison change, P < .001). Knowledge of the physical activity recommendation (â„150 minutes weekly) increased from 2.6% to 62.4% among intervention participants and from 1.0% to 2.5% among comparison participants (P < .001). Consumption of 5 or more daily servings of fruits and vegetables increased more in the intervention group (8.4% to 62.1%) than in the comparison group (5.1% to 12.7%) (P < .001). Participants reporting 150 minutes or more of physical activity weekly increased from 28.9% to 54.0% in the intervention group and from 38.0% to 46.8% in the comparison group (intervention vs comparison change, P = .001).ConclusionA lay health worker intervention increased both healthy eating and physical activity knowledge and self-reported behaviors among older Vietnamese Americans
Recommended from our members
A Cluster Randomized Controlled Trial of a Lay Health Worker Intervention to Increase Healthy Eating and Physical Activity Among Vietnamese Americans.
IntroductionAmericans have low levels of knowledge of and adherence to recommendations for healthy eating of fruits and vegetables and for physical activity (HEPA). We conducted a cluster randomized controlled trial of a lay health worker intervention to increase HEPA among Vietnamese Americans.MethodsWe randomized 64 lay health workers to 2 intervention arms. Each lay health worker recruited 10 participants aged 50 to 74. From 2008 to 2013, using flip charts, lay health workers led 2 educational sessions on HEPA (intervention) or colorectal cancer (comparison). We assessed HEPA knowledge and self-reported behaviors by preintervention and postintervention surveys 6 months apart.ResultsOf the 640 participants, 50.0% were female, 38.4% had lived in the United States for 10 years or fewer, and 71.4% reported limited English proficiency. Knowledge of the recommended intake of fruits and vegetables (â„5 servings daily) increased from 2.6% to 60.5% in the intervention group (n = 311) and from 2.9% to 6.7% in the comparison group (n = 316) (intervention vs comparison change, P < .001). Knowledge of the physical activity recommendation (â„150 minutes weekly) increased from 2.6% to 62.4% among intervention participants and from 1.0% to 2.5% among comparison participants (P < .001). Consumption of 5 or more daily servings of fruits and vegetables increased more in the intervention group (8.4% to 62.1%) than in the comparison group (5.1% to 12.7%) (P < .001). Participants reporting 150 minutes or more of physical activity weekly increased from 28.9% to 54.0% in the intervention group and from 38.0% to 46.8% in the comparison group (intervention vs comparison change, P = .001).ConclusionA lay health worker intervention increased both healthy eating and physical activity knowledge and self-reported behaviors among older Vietnamese Americans