•NiO/PPy hybrid films synthesized by simple vapour-phase polymerization.•NiO/PPy ratios obtained by regulating FeCl3 oxidant contents on NiO-nanoparticles.•NiO/PPy hybrid films having high sensing ...performance of response, selectivity, and reversibility to NH3 gas.•Experimental results verified the existence of NiO/PPy hybrid structure.
In this work, NiO/PPy hybrid nanostructured films were fabricated by chemical vapor-phase polymerization using NiO nanoparticles films drop-coated FeCl3 oxidant on Al2O3 substrates. The NiO nanoparticles with a size of about 20 nm were synthesized by a hydrothermal method. Different ratios between NiO and PPy in the NiO/PPy hybrid films were modified by regulating FeCl3 oxidant content when using FeCl3 solutions with concentrations of 0.15, 0.2, 0.4, 0.8, and 1.5 M. X-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, Fourier-transform infrared spectroscopy, and Raman scattering spectroscopy were used to analyze specific material characteristics of these films. The gas-sensing performance of the films was examined by exploring their resistances responding to NH3, NO2, H2, CO, and relative humidity at an operating temperature range from 25 to 110 °C. The NiO/PPy hybrid films presented to have a very high sensitivity to NH3 gas in comparison to the non-hybrid films based on only NiO or PPy. The highest sensitivity to NH3 gas (the sensing response S = 246.6 % for 350 ppm at 25 °C) was found for the NiO/PPy film with the used 0.2 M FeCl3 oxidant solution. The gas-sensing performance of the NiO/PPy films was suggested by the main contribution of the hybrid nanostructure between NiO nanoparticles and PPy.
Two planthopper species of the family Nogodinidae are added to the fauna of Vietnam, both from two localities in Thua Thien-Hue Province: Bach Ma National Park and Phong Dien District. The first ...species belongs to
Meng, Wang & Wang, 2014,
Constant & Pham,
, and the second belongs to
Distant, 1906,
Meng, Wang & Wang, 2014.
was previously recorded from Hainan Island, China. These new records greatly extend the distribution of both genera, which were known from southern China, Hainan and North Vietnam, to the south, reaching the mid area of Central Vietnam. Sexual dimorphism is reported in
for the first time. Illustrations of habitus and male terminalia of the new species are given as well as distribution maps and photographs of live specimens and their habitat. The family Nogodinidae now comprises nine species in Vietnam, with three of them present in Bach Ma National Park.
We reported the synthesis and full characterization of ultralong Bi2S3 nanowires with diameters of 60–80 nm and lengths above 1 μm, showing growth in the 001 direction. Combining the computed lattice ...dynamics of orthorhombic Bi2S3 with the experimental micro-Raman scattering study provided comprehensive solutions. We demonstrate that 10 active modes originated from Raman symmetry modes (4Ag + 2B1g + 3B2g + 1B3g), and the peak at 124 cm–1 is due to the IR-active B3u mode. The use of the Bi2S3 catalyst for dewatering hexavalent chromium-containing wastewater was also reported. This confirms it to be a potential candidate for photocatalytic environmental remediation.
Growth faltering is associated with adverse consequences during childhood and later life. However, questions remain on the relative importance of preconception maternal nutritional status (PMNS) and ...child growth during the first 1000 d of life.
We examined associations between PMNS, gestational weight gain (GWG), and child growth during the first 1000 d with attained body size at age 6–7 y.
We used data from a follow-up of a double-blinded randomized controlled trial of preconception micronutrient supplementation in Vietnam (n = 5011 women). The outcomes included offspring height-for-age z score (HAZ), BMI-for-age z score (BMIZ), and prevalence of stunting and overweight/obese at age 6–7 y (n = 1579). We used multivariable linear and Poisson regression models to evaluate the relative contributions of PMNS (height and BMI), GWG, and conditional growth in 4 periods: fetal, 0–6 mo, 6–12 mo, and 12–24 mo.
PMNS was positively associated with child-attained size at 6–7 y. For each 1-SD higher maternal height and BMI, offspring had 0.28-SD and 0.13-SD higher HAZ at 6–7 y, respectively. Higher maternal BMI and GWG were associated with larger child BMIZ (β: 0.29 and 0.10, respectively). Faster linear growth, especially from 6 to 24 mo, had the strongest association with child HAZ at 6–7 y (β: 0.39–0.42), whereas conditional weight measures in all periods were similarly associated with HAZ (β: 0.10–0.15). For BMIZ at 6–7 y, the magnitude of association was larger and increased with child age for conditional weight gain (β: 0.21–0.41) but smaller for conditional length gain. Faster growth in the first 2 y was associated with reduced risk of stunting and thinness but increased risk of overweight/obese at 6–7 y.
Interventions aimed at improving child growth while minimizing the risk of overweight during the school age years should target both women of reproductive age prior to conception through delivery and their offspring during the first 1000 d. The trial was registered at clinicaltrials.gov as NCT01665378.
Fatal consequences of freshwater pearl diving Phu, Nguyen Hoan, MD; Hoang Mai, Nguyen Thi, MD; Nghia, Ho Dang Trung, MD ...
Lancet,
01/2013, Letnik:
381, Številka:
9861
Journal Article
Recenzirano
Odprti dostop
Polymerase chain reaction (PCR) amplification targeting the 18s RNA gene was done retrospectively.1 The PCR amplicon was sequenced and confirmed to have 100% homology with the 18s RNA gene of ...Naegleria fowleri, which is the cause of primary amoebic meningoencephalitis. Within the central nervous system N fowleri amoebae cause an intense inflammatory reaction accompanied by necrosis and haemorrhage.3 Amoebic meningoencephalitis seems to be increasing in frequency with an expanding geographic footprint.4,5 Clinical and CSF findings are difficult to distinguish from bacterial meningitis.5 A history of freshwater exposure and symptoms such as the loss of the sense of smell should prompt consideration of the disease.4 The infection has a very high case-fatality rate and very few survivors have been documented.
In this study, chemical components, α-glucosidase inhibitory activities, and molecular modelling studies of the essential oil extracted from the Cleistocalyx operculatus leaves were investigated. In ...total, thirty compounds were identified using GC/MS, representing 98.3% of the oil. Of these, the two most dominant constituents of the essential oil were determined as (Z)-β-ocimene (30.4%) and allo-ocimene (31.6%). The α-glucosidase inhibitory experiments indicated that the essential oil exhibited potent α-glucosidase inhibitory activities, with IC50 values of 61.82 ± 3.91 µg/mL. For further investigation into inhibitory mechanisms, molecular docking simulations were performed to investigate structural interactions between two dominant constituents and the α-glucosidase protein. The simulation revealed that allo-ocimene (31.6%) and (Z)-β-ocimene (30.4%) have protein binding affinities of −5.358 and −5.330 kcal/mol, respectively. Moreover, molecular dynamic simulation indicated that the complexes of two compounds and the target protein were stable over 100 ns. Overall, these findings suggest that the essential oil of C. operculatus leaves could be a natural source of potential α-glucosidase inhibitors.
Although there is growing evidence on the role of preconception nutrition for birth outcomes, very few studies have evaluated the long-term effects of nutrition interventions during the preconception ...period on offspring cognitive outcomes.
We evaluate the impact of preconception weekly multiple micronutrients (MMs) or iron and folic acid (IFA) supplementation compared with folic acid (FA) alone on offspring intellectual functioning at age 6–7 y.
We followed 1599 offspring born to women who participated in a double-blinded randomized controlled trial of preconception supplementation in Vietnam. Women received weekly supplements containing either 2800 μg FA only, 60 mg iron and 2800 μg FA, or MMs (15 micronutrients including IFA) from baseline until conception, followed by daily prenatal IFA supplements until delivery. We used the Wechsler Intelligence Scale for Children to measure full-scale IQ (FSIQ) and 4 related domains of intellectual functioning Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), and Processing Speed Index (PSI) scores at 6–7 y. Group comparisons were done using ANOVA tests for all children and the subgroup born to women who consumed the supplements ≥26 wk before conception (per-protocol analyses).
The final sample with data at 6–7 y (n = 1321) was similar for baseline maternal and offspring birth characteristics and age at follow-up by treatment group. Compared with the offspring in the FA group, those in the MM group had higher FSIQ (β = 1.7; 95% CI: 0.1, 3.3), WMI (β = 1.7; 95% CI: 0.2, 3.2), and PSI (β = 2.5; 95% CI: 0.9, 4.1). Similar findings were observed in the per-protocol analyses. There were no significant differences by treatment group for VCI and PRI.
Preconception supplementation with MMs improved certain domains of intellectual functioning at age 6–7 y compared with FA. These findings suggest the potential for preconception micronutrient interventions to have long-term benefits for offspring cognition.
The current thermoremendable polyurethanes (PUs) based on reversible Diels–Alder (DA) chemistry featuring both good mechanical properties and efficient macrodamage healability are up to now built ...with the DA bonds located in the hard domains with restricted mobility, which hinders the DA reversibility. Thus, the healing process in these materials requires predissociation of DA bonds via the retro reaction at high temperatures (110–180 °C) followed by DA re-formation, which may compromise the material performance integrity. Here, we show a design of thermoset PUs containing dynamic DA entities engineered at the interface between the hard and soft domains that combine high modulus and toughness with mild-temperature-triggered molecular mobility, which is a prerequisite for efficient healing capability. This concept of molecular design enables PUs to have great mechanical properties (Young’s modulus ∼80–225 MPa, ultimate tensile strength ∼16–30 MPa, and toughness ∼26–96 MJ m–3) and simultaneously remarkable healing ability at mild temperatures (60–70 °C) of macroscratches, punctures, and complete cuts. The mechanical and healing properties can be tuned by varying the DA bond content. These materials are the first reported DA-based PU materials showing excellent healing efficiency at mild temperatures without compensation of their great mechanical properties.
Millions of children fail to meet their developmental potential and experience mental health concerns globally. Evidence is mixed on whether growth beyond the first 1000 d of life influences ...intellectual functioning and mental health in school-age children.
We examined associations of childhood growth before and after the first 1000 d of life with child intellectual functioning and mental health at age 6–7 y.
We used data from a follow-up of a randomized controlled trial of preconception supplementation (PRECONCEPT study) in Vietnam. A total of 5011 women participated in the study and 1579 children were born during 2012–2014. At age 6–7 y, child intellectual functioning was assessed using the Wechsler Intelligence Scale for Children, and mental health concerns were measured using the Strengths and Difficulties Questionnaire. Multivariable linear models were used to examine the independent association of child size at age 2 y height-for-age z-score (HAZ) and body-mass-index z-score (BMIZ) and conditional measures of linear and ponderal growth between the ages of 2 and 7 y.
HAZ at 2 y was positively associated with the Full-Scale Intelligence Quotient (β = 1.4; 95% CI: 0.5, 2.2 points) and its subdomains, namely Perceptual Reasoning Index, Working Memory Index, and Processing Speed Index (β = 1.0–1.4 points). Higher HAZ at 2 y was associated with lower overall mental health concerns (β = −0.24; 95% CI: −0.47, −0.01) and peer problems (β = −0.08; 95% CI: −0.17, −0.01). Faster height gain between 2 and 7 y was associated with higher total intellectual functioning (β = 0.9; 95% CI: 0.02, 1.8) and fewer emotional issues (β = −0.09; 95% CI: −0.18, −0.01). BMIZ at 2 y was not associated with intellectual functioning but was marginally associated with higher conduct and peer problems. Conditional weight gain between 2 and 7 y was not associated with child intellectual functioning or mental health in young school-age children.
Child linear growth both during and beyond the first 1000 d is positively associated with intellectual functioning and mental health during the early school-age years.
infection is prevalent and has a rapidly increasing antibiotic resistance rate in Vietnam. Reinfection is quite common, and gastric carcinoma remains one of the most common malignancies, which is not ...uncommon to develop after successful eradication. The purpose of this consensus is to provide updated recommendations on the management of
infection in the country. The consensus panel consisted of 32 experts from 14 major universities and institutions in Vietnam who were invited to review the evidence and develop the statements using the Delphi method. The process followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The consensus level was defined as ≥80% for agreement on the proposed statements. Due to the limited availability of high-quality local evidence, this consensus was also based on high-quality evidence from international studies, especially those conducted in other populations in the Asia-Pacific region. The panel finally reached a consensus on 27 statements after two voting rounds, which consisted of four sections (1) indications for testing and selection of diagnostic tests (2), treatment regimens, (3) post-treatment confirmation of
status, and (4) reinfection prevention methods and follow-up after eradication. Important issues that require further evidence include studies on third-line regimens, strategies to prevent
reinfection, and post-eradication follow-up for precancerous gastric lesions. We hope this consensus will help guide the current clinical practice in Vietnam and promote multicenter studies in the country and international collaborations.
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