18 research outputs found
Assessing Regional Hydro-Climate Impacts Using High Resolution Climate Modelling: A Study over Vietnam
Ph.DDOCTOR OF PHILOSOPH
DEVELOPMENT OF ELECTROACTIVE POLYMETHYLTHIOPHENE BASED DOPAMINE SENSOR
Joint Research on Environmental Science and Technology for the Eart
Would Bangkok Be More Vulnerable To The Anticipated Changing Climate?
The severe flooding in Thailand in 2011 was triggered by the tropical storm Nock-ten at end of July along the Mekong and Chao Phraya river basin. There are 4 additional storms that caused medium to heavy rainfall from June to October in the north and north-east of Thailand. Due to limited capacity of the Chao Phraya river and also Pasak river, several overbank flows occurred and also dikes along the river were broken causing excessive flow to many communities beside the river and downstream. The consequence was a total of 815 deaths with 13.6 million people affected and over 20,000 km2 farmland devastated, the inundation remained until mid-January 2012. Total estimated cost of economic lost was about 45.7 billion US$ with respect to manufacturing industry as seven major industrial estate in the northern provinces of Bangkok were submerged 2-3 m during high flood. This caused interruption to supply chain to car parts regionally and world-wide, e.g. electronic components and hard disk drives. Will Bangkok experience more intense rainfall under the changing climate? The Artificial Neural Network (ANN) technique is adopted in this study to shed some lights on this issue. ANN is an established technique with a flexible mathematical structure that is capable of identifying complex non-linear relationships between input and output data. The present study utilizes ANN to statistically downscale global climate models (GCMs) at some meteorology stations in Bangkok. The study illustrates the applications of the feed forward back propagation using large-scale predictor variables derived from the ERA-Interim reanalysis data, meteorological station data (predictand), present and future GCM data of certain emission scenarios. The findings will certainly be useful to the policy makers in pondering, e.g. whether the current drainage network system is sufficient to meet the changing climate, and a range of flood adaptation and mitigation measures
A Clinical and Epidemiological Investigation of the First Reported Human Infection With the Zoonotic Parasite Trypanosoma evansi in Southeast Asia.
BACKGROUND: Trypanosomais a genus of unicellular parasitic flagellate protozoa.Trypanosoma bruceispecies and Trypanosoma cruziare the major agents of human trypanosomiasis; other Trypanosomaspecies can cause human disease, but are rare. In March 2015, a 38-year-old woman presented to a healthcare facility in southern Vietnam with fever, headache, and arthralgia. Microscopic examination of blood revealed infection with Trypanosoma METHODS: Microscopic observation, polymerase chain reaction (PCR) amplification of blood samples, and serological testing were performed to identify the infecting species. The patient's blood was screened for the trypanocidal protein apolipoprotein L1 (APOL1), and a field investigation was performed to identify the zoonotic source. RESULTS: PCR amplification and serological testing identified the infecting species as Trypanosoma evansi.Despite relapsing 6 weeks after completing amphotericin B therapy, the patient made a complete recovery after 5 weeks of suramin. The patient was found to have 2 wild-type APOL1 alleles and a normal serum APOL1 concentration. After responsive animal sampling in the presumed location of exposure, cattle and/or buffalo were determined to be the most likely source of the infection, with 14 of 30 (47%) animal blood samples testing PCR positive forT. evansi. CONCLUSIONS: We report the first laboratory-confirmed case ofT. evansiin a previously healthy individual without APOL1 deficiency, potentially contracted via a wound while butchering raw beef, and successfully treated with suramin. A linked epidemiological investigation revealed widespread and previously unidentified burden ofT. evansiin local cattle, highlighting the need for surveillance of this infection in animals and the possibility of further human cases
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
Investigating drought over the Central Highland, Vietnam, using regional climate models
10.1016/j.jhydrol.2014.11.006Journal of Hydrology526265-27
New anthracene-based Cu(I) dithiocarbamates as AIEgens
The syntheses and structural characterizations of a series of anthracene-tethered Cu(I) phosphine dithiocarbamate complexes, [CuL(PPh3)2], are described in this article. All complexes were readily prepared from corresponding ligands with various acyclic and cyclic N-alkyl substituents and [Cu(PPh3)2(NO3)]. Steric hindrance imposed on the anthracenyl rings by dithiocarbamate, N-alkyl substituents and triphenylphosphine moieties in complexes 1-6 are not detected, as evidenced by the sharp aromatic resonances in 1H NMR spectra. X-ray crystallography reveals distorted tetrahedral chelation environments around the Cu(I) centers in 2 and 3 as well as extensive C–S···π and C–H···π intermolecular interactions in their solid state packings. The complexes display characteristic anthracene-based absorption and emission properties. The emission quantum yields of the complexes are poor (1.0–2.7 × 10−2) but the aggregation-induced emission effects are perceived in aqueous DMSO solutions. Especially, 6 with N-substituted cyclohexyl group displays the largest increase in emission intensity (ca. 7 times).</p
Projected Evolution of Drought Characteristics in Vietnam based on CORDEX-SEA Downscaled CMIP5 Data
In this study, the projected drought characteristics over Vietnam for the future periods of the middle (2046–2065) and end of the 21st century (2080–2099) were investigated under the Representative Concentration Pathway (RCP) scenarios RCP4.5 and RCP8.5. The drought characteristics (duration, severity, intensity, inter-arrival time, and geographic extent) were estimated based on the Palmer Drought Severity Index (PDSI). The PDSI was calculated using temperature and precipitation data from six regional climate downscaling experiments and their ensemble conducted by the Coordinated Regional Climate Downscaling Experiment-Southeast Asia (CORDEX-SEA) project. Projected changes of drought characteristics in the future periods were determined with respect to those in the baseline period 1986–2005. Results show biases in the regional climate model (RCM) outputs, namely an underestimation of temperature and an overestimation of precipitation, which also affect the representation of drought characteristics by overestimating the PDSI. In terms of projections, substantial increases of drought duration, severity and intensity, and decreases in the inter-arrival time are found over the Red River Delta, northern parts of the North Central sub-region, parts of the Central Highlands and over southern Vietnam. The droughts are projected to be more widespread under scenario RCP8.5 than RCP4.5, especially in southern Vietnam. With the increasing likelihood of droughts in Vietnam as a result of climate change, sustainable water resources management should be taken into account for agriculture, natural ecosystems and social development