Long short-term memory (LSTM) neural networks for short-term water level prediction in Mekong river estuaries

This study firstly adopts a state-of-the-art deep learning approach based on a Long Short-Term Memory (LSTM) neural network for predicting the hourly water level of Mekong estuaries in Vietnam. The LSTM models were developed from around 8,760 hourly data points within 2018 and were evaluated using the Nash-Sutcliffe efficiency coefficient (NSE), mean absolute error (MAE), and root mean square error (RMSE). The results showed that the NSE values for the training and testing steps were both above 0.98, which can be regarded as very good performance. Furthermore, the RMSE were between 0.09 and 0.11 m for the training and between 0.10 and 0.12 m for the testing, while MAE for the training ranged from 0.07 to 0.08 m and varied from 0.08 to 0.10 m for the testing. The LSTM networks appear to enable high precision and robustness in water level time series prediction. The outcomes of this research have crucial implications in river water level predictions, especially from the viewpoint of employing deep learning algorithms

Streptococcus suis, an Important Cause of Adult Bacterial Meningitis in Northern Vietnam

Streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. S. suis is often misdiagnosed, due to lack of awareness and improper testing. Here we report the first fifty cases diagnosed with S. suis infection in northern Viet Nam.In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months.S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen

Quantifying the Emergence of Dengue in Hanoi, Vietnam: 1998–2009

Dengue is the most common vector-borne viral disease of humans, causing an estimated 50 million cases per year. The number of countries affected by dengue has increased dramatically in the last 50 years and dengue is now a major public health problem in large parts of the tropical and subtropical world. It is of considerable importance to understand the factors that determine how dengue becomes newly established in areas where the risk of dengue was previously small. Hanoi in North Vietnam is a large city where dengue appears to be emerging. We analyzed 12 years of dengue surveillance data in order to characterize the temporal and spatial epidemiology of dengue in Hanoi and to establish if dengue incidence has been increasing. After excluding the two major outbreak years of 1998 and 2009 and correcting for changes in population age structure over time, we found there was a significant annual increase in the incidence of notified dengue cases over the period 1999–2008. Dengue cases were concentrated in young adults in the highly urban central areas of Hanoi. This study indicates that dengue transmission is increasing in Hanoi and provides a platform for further studies of the underlying drivers of this emergence

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Excess water storage depth - a water management practice to control simetryn and thiobencarb runoff from paddy fields

Experiments were carried out to verify the effectiveness of the excess water storage depth (EWSD) in reducing runoff losses of simetryn and thiobencarb from paddy fields upon appreciable rainfall events. A paddy plot having an EWSD of 2 cm was effective in controlling runoff with the herbicide losses of less than 1% of the applied herbicides. Meanwhile, a plot with 0-cm EWSD lost 18.1 and 3.7% of the applied mass of simetryn and thiobencarb, respectively. Therefore, an appropriate EWSD is essential during the recommended 7-day water holding period in order to completely hold the water inside the field in case of rainfall

Functional Nanostructured Oligochitosan–Silica/Carboxymethyl Cellulose Hybrid Materials: Synthesis and Investigation of Their Antifungal Abilities

Functional hybrid materials were successfully synthesized from low-cost waste products, such as oligochitosan (OCS) obtained from chitosan (one of the main components in crab shells) and nanosilica (nSiO2) obtained from rice husk, in a 1:1 ratio (w/w), and their dispersion in the presence of carboxymethyl cellulose at pH 7 was stable for over one month without aggregation. The molecular weights, chemical structures, morphologies, and crystallinities of the obtained materials were characterized by GPC, FTIR, TEM, and XRD, respectively. The antifungal effects of OCS, nSiO2, and the OCS/nSiO2 hybrid materials were investigated via a disk-diffusion method. The results showed that the nanohybrid materials had better resistance to Phytophthora infestans fungus than the individual components, and a concentration of the OCS2/nSiO2 hybrid material of 800 mg L&minus;1 was the lowest concentration where the material completely inhibited Phytophthora infestans growth, as measured via an agar dilution method. This study not only creates a novel environmentally friendly material with unique synergistic effects that can replace current toxic agrochemicals but also can be considered a new platform for further research in green agricultural applications

Synthesis of Platinum Nanoparticles by Gamma Co-60 Ray Irradiation Method Using Chitosan as Stabilizer

Platinum nanoparticles were synthesized using the gamma-ray irradiation as a reducing factor and chitosan as a stabilizer. The prepared platinum nanoparticles were characterized using ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FT-IR). The saturated conversion dose to reduce the Pt4+ to Pt0 was found to be about 14 kGy for initial Pt4+ concentration of 1 mM. The size of the platinum nanoparticles (1.4–1.6 nm) did almost not change with the increase of chitosan concentration from 0.5 to 2.0%. Thus, gamma Co-60 ray irradiation method is favorable for synthesizing PtNPs with the small sizes

Silver, Gold, and Silver-Gold Bimetallic Nanoparticle-Decorated Dextran: Facile Synthesis and Versatile Tunability on the Antimicrobial Activity

The noble metal-based nanoparticles (NPs) have been considered as potential antimicrobial agents because of their good antibacterial and antifungal activities as well as biocompatible nature. In this study, we have introduced a simple and fast route to synthesize silver, gold, and silver-gold bimetallic NP-decorated dextran. The as-synthesized noble metal-based NPs with spherical geometry showed high dispersity in dextran. The antibacterial and antifungal of obtained nanomaterials were tested with Xanthomonas oryzae pv. oryzae (Xoo) bacteria and Magnaporthe grisea (M. grisea) fungi. The silver NPs and bimetallic NPs with high silver content in dextran exhibited excellent activity to inhibited the growth of the bacteria and fungi, whereas the gold/dextran has weak antimicrobial effects. The antibacterial and antifungal properties of silver-gold bimetallic NPs in dextran biopolymer can be tuned according to the content of silver in the bimetallic NPs. The obtained nanomaterials could open an entry to a new class of antibiotics