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Tin dioxide (SnO2) has recently been recognized as an excellent electron transport layer (ETL) for perovskite solar cells (PSCs) due to its advantageous properties, such as its high electron mobility, suitable energy band alignment, simple low-temperature process, and good chemical stability. In this work, nitrogen-doped graphene quantum dots (N-GQDs) were prepared using a hydrothermal method and then used to fabricate N-GQD:SnO2 nanocomposite ultrathin films. N-GQD:SnO2 nanocomposite ultrathin films were investigated and applied as electron transport layers in planar PSCs. The presence of N-GQDs with an average size of 6.2 nm in the nanocomposite improved its morphology and reduced surface defects. The excitation–emission contour map indicated that the N-GQDs exhibited a remarkably enhanced light-harvesting capability due to the possibility of absorbing UV light and producing emissions in the visible range. The quenching of photoluminescence spectra showed that the N-GQDs in nanocomposite ultrathin films improved electron extraction and reduced charge recombination. As a result, the power conversion efficiency (PCE) of our planar PSCs fabricated with the optimized N-GQD:SnO2 nanocomposite electron transport layer was improved by 20.4% over pristine SnO2-based devices.

In this work, we report on the synthesis of Ni-doped WO3 flakes by the hydrothermal method. The physical and chemical properties of the synthesized Ni-doped WO3 flakes were thoroughly investigated by scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, Raman spectroscopy, photoluminescence spectrum, X-ray diffraction, X-ray photoelectron spectroscopy, and N2 adsorption–desorption measurement, thereby confirming the effect of Ni doping on H2S-sensing properties. The sensitivity to H2S gas of Ni-doped WO3 flakes showed short response/recovery times of 17 s/110 s, high stability, good selectivity, and low operating temperature of 250 °C. Due to the increasing surface defects and oxygen vacancies with the presence of Ni2+ ions in the structure of WO3 flakes, the Ni-doped WO3 sensor exhibited a better sensing of H2S gas than the pristine WO3 sensor. This result indicates that the Ni-doped WO3 flake structure is promising for detecting H2S gas as a selective, inexpensive, and outstanding sensor materials.

Na4Mn9O18 was recognized as the most interesting material for sodium ion batteries due to its low cost, high specific capacity and good cycle performance. The excellent electrochemical performance of Na4Mn9O18 nanostructures was shown in literature. In this work, Na4Mn9O18 nanowires were synthesized by hydrothermal reactions of Mn2O3 powder and NaOH solution at the temperatures of 185–205 °C for 48–96 h. The investigation of composition and structure of the synthesized products via scanning electron microscopy and X-ray diffraction analyses showed that major intermediate products at the low and high temperatures were Mn3O4 and birnessite Na0.55Mn2O41.5H2O, respectively. The synthesized Na4Mn9O18 nanowires showed a good electrochemical performance with discharge capacities of over 90 mAhg−1, and Coulombic efficiencies of more than 91% at a rate of 0.2C during 30 cycles of charge/discharge.

We report on the synthesis of perovskite Cs2SnI6 films via the solution–processed approach. The cubic Cs2SnI6 phase (Fm3m group) formed at the annealing temperature of 170 °C for 8 h in air has uniform morphology. The optical characteristics of the compound depended on the annealing temperature and the compound behaved like a direct band gap semiconductor. Based on these findings, we firstly investigated the potential application of Cs2SnI6 to photoelectrochemical (PEC) water splitting using a 0.3 M NaCl electrolyte. The photocurrent density (PCD) and photoconversion efficiency (η) were 0.92 mA cm−2 and 0.54% at −0.8 V, respectively. This might be suitable for fabricating the hybrid PEC device.

We report on the synthesis of Sn-doped hematite nanoparticles (Sn-α-Fe2O3 NPs) by the hydrothermal method. The prepared Sn-α-Fe2O3 NPs had a highly pure and well crystalline rhombohedral phase with an average particle size of 41.4 nm. The optical properties of as-synthesized α-Fe2O3 NPs show a higher bandgap energy (2.40–2.57 eV) than that of pure bulk α-Fe2O3 (2.1 eV). By doping Sn into α-Fe2O3 NPs, the Sn-doped hematite was observed a redshift toward a long wavelength with increasing Sn concentration from 0% to 4.0%. The photocatalytic activity of Sn-doped α-Fe2O3 NPs was evaluated by Congo red (CR) dye degradation. The degradation efficiency of CR dye using Sn-α-Fe2O3 NPs catalyst is higher than that of pure α-Fe2O3 NPs. The highest degradation efficiency of CR dye was 97.8% using 2.5% Sn-doped α-Fe2O3 NPs catalyst under visible-light irradiation. These results suggest that the synthesized Sn-doped α-Fe2O3 nanoparticles might be a suitable approach to develop a photocatalytic degradation of toxic inorganic dye in wastewater.

Background: Chronic urticaria (CU) is characterized by repeated occurrence of wheals and itching for more than 6 weeks. Treatment of chronic urticaria with traditional medicine has been shown to relieve symptoms and prevent recurrence. In recent years, more and more evidence-based studies of CU treatment by Traditional medicine were report, including acupuncture, herbs, and food. Objective: To evaluate the efficacy of Duong-Quy-Luc-Hoang (DQLH) decoction in treatment of Chronic Urticaria. Material and Method: Including 30 patients with chronic urticaria had been treated by DQLH decoction in Faculty of Traditional Medicine, Hue Central Hospital. Prospective study, clinical intervention, comparison before and after treatment. Results: The decoction of DQLH has efficacy in 100% patient, include 56.7% of patient who became symtom-free. There is no side effects observed during the progress of this study. Key words: Chronic urticarial, Duong-quy-luc-hoang decoction, Traditional medicine

This paper discusses the sexual experiences of people with physical disabilities in Vietnam. The research on which this paper is based adopted a qualitative research with in-depth interviewing in combination with the photo elicitation method. Twenty Participants with physical disabilities participated in this study. During the interviews, participants were offered the options of drawing a picture or selecting some images from a small photo library that expressed their thoughts if they found questions difficult to answer. The findings revealed sexual experiences of people with physical disabilities regarding premarital sex, sexual activities, types of sex and orgasm. They expressed that they experienced sexuality in many ways. This research also found some sexual problems and participants’ sexual desire. Despite some limitations caused by their disabilities, they were still satisfied with their sexual activities. However, some encountered sexual problems, particularly coercion and other difficulties such as abuse and domestic violence. Although they experienced some challenges with their sexual lives, they tried to deal with these problems in order to have a better sexual life.

This paper discusses the knowledge of sexual and reproductive health among people with physical disabilities in Vietnam. A qualitative research design was adopted. In-depth interviewing and photo elicitation methods were used to collect stories from 20 participants. The findings suggest that without formal education about sexual and reproductive health people with physical disabilities in Vietnam gain knowledge through their experiences and from informal sources of information. Participants perceived safe sex to include contraceptive methods, prevention of sexually transmitted diseases, having orgasm together and finding balance between health and sexual needs. Participants related reproductive health to fertility, restriction of family size, sexually transmitted diseases, and self-care in pregnancy. Reasons for insufficient knowledge included limited education due to: disability and poor family background; limited education on sexual and reproductive health issues; absence of family and community discourse about sexual and reproductive health; and lack of information resources. Participants acknowledged that their knowledge was inadequate. They wanted to know more about sexual and reproductive health but lacked access to the relevant information. Health care providers, researchers, and policy-makers in Vietnam should address the gaps in sexual and reproductive health care knowledge among people with disabilities in Vietnam and those that provide care to them.

In this study, we report on the synthesis of SnS/Ag/SnS trilayer films for photovoltaic applications by the radio frequency (RF) sputtering method. The effect of the Ag thin film on the physical properties of the SnS film was systematically investigated. The SnS/Ag/SnS trilayer film solar cell obtained a higher short circuit current density (Jsc) of 17.13 mA/cm2 and a higher efficiency (ηmax) of 5.24% than those of the SnS film solar cell (Jsc = 14.21 mA/cm2, η = 3.23%). The improved photocurrent density (PCD) mainly resulted from the enhancement of the separation efficiency of photogenerated electron-hole pair and the decrease in trapping charge carriers in impurity centers as well as the reduction of the leakage current in the active region. These results could be useful for fabricating the next-generation photovoltaic device with high efficiency.

This work investigated the effect of oxygen vacancy (OV) and Au nanoparticles on the photoelectrocatalytic activities of Au@TiO2 photoanodes. The Au@TiO2 films on FTO substrates were prepared by the spin-coating method using emulsions of Au NPs (~4 nm) and TiO2 NPs (~20 nm) dispersing in ethanol. The OV concentration in the TiO2 NPs was controlled by annealing the photoanodes in vacuum and air for different time periods. The absorbance, photoluminescence, and linear sweep voltammetry spectra of the photoanodes were investigated. The experiment results indicated that the increment of the OV concentration enhanced photoelectrocatalytic activity of the TiO2 photoanodes but moderated the activity of the Au@TiO2 photoanodes. These effects were explained based on the Schottky barrier between the Au and TiO2 nanoparticles.

This article provides an overview on reproductive and sexual health of people with physical disabilities in developed and underdeveloped countries from 1995 to 2011. Based on the metasynthesis approach, the authors reviewed 15 qualitative studies. These studies were searched using Medline, CINAHL, CINAHL (health), ProQuest Central, Google Scholar, Cochrane, Embase, Informit Health, Sciences Direct, Pubmed, Pubmed Health, AAHD (abstracts), ProQuest Journal (sexuality and disability) and were also manually searched. All studies were judged on their qualities using the Critical Appraisal Skills Programme. Reproductive health, sexual attractiveness and experiences, reproductive and sexual health knowledge, and dealing with reproductive and sexual health issues were four main themes that emerged from these studies. This paper proposes a new model to explain the factors that impacted the reproductive and sexual life of people with physical disabilities: internal and external factors. Implications for health and social care are discussed in light of the findings.

We present the synthesis of ZnO nanostructures via the solvothermal method with the assistance of ethylene glycol and nickel acetate tetra hydrate, NA. By employing the NA, the synthesized ZnO structures had different morphologies. The synthesized ZnO material was characterized by scanning electron microscopy, x―ray diffraction, Raman spectroscopy, and energy dispersive spectroscopy. The sensitivity to NO2 gas of the synthesized ZnO was investigated using NO2 concentration of 0.25―1.0 ppm at operating temperature of 150―350 °C. The results indicated that the ZnO nanorods could be suitable for NO2 sensors. Based on these findings, we propose fabrication of a sensor detecting NO2 gas at the sub―ppm concentration.

Background: Lumbar waist syndrome is one of the most common diseases in the world as well as in Vietnam. Objectives: Evaluating the effects of the electronic – acupuncture of combine with “Hoatua Jajie” points on treatment for lumbar waist syndrome. Methods: The sample is 64 patients diagnosed lumbar waist syndrome, divided equally into two groups of study and control group. The treatment term had lasted for 15 days. Results: The study group has better result (p < 0.05) with very good level (25%) good (43.75%) and moderate (31.25%). There was not any unexpected effects observed in this trial. Conclusion: The electronic – acupuncture of combine with “Hoatua Jajie” points is safe method and has good effect on treatment for lumbar waist syndrome. Key words: Lumbar waist syndrome, “Hoatua Jajie” points, electronic – acupuncture

Garlic powder was irradiated by gamma-rays from a Co-60 source to reduce microbialcontamination for prolong the storage and preservation time. Results showed that the initial microbial number of about 106CFU/g contaminated in garlic powder was exceeded for the set standard of TCVN 7809 – 2007 and ISO 5560 – 1997. The total aerobic bacteria and yeast mold cells of irradiated garlic powder were reduced from 106 CFU/g to 104, 6103 and 6102 CFU/g at doses of 0, 4, 8 and 12 kGy, respectively. The level of microbial contamination was significantly reduced by irradiation at 4 kGybut it is only appropriate for domestic acceptance. At the irradiation doses of 8 and 12 kGy, the level of microbial contamination was further reduced after storage for two months and it is appropriate to export. In addition, the irradiated garlic powder was in good quality with no change of moisture, oil content and sensory properties. Thus, gamma Co-60 irradiation is a very effective method for reducing the number of microbial contaminated in garlic powder.

Introduce: Fascioliasis is an infection common in animals,particularly sheep and cattle, and is widespread around the world. The disease can be transmitted through food to Humans where it affects the liver. It is also known as “common liver fluke infection”. Material and method: Include 326 person with suspected infection of fasciolasis, and recived ELISA from 4/2012 to 6/2013 at Hue Central Hospital. Result: The rate of ELISA positive liver for 31.3%, men 24.4%, women 38.3%, rural areas accounted for 36.8%, Farmer group 36.2%. Conclusion: Prevalence of Fasciolisis with symptoms suggestive in clinically is 31.3%. Main source of contamination due to people eating aquatic plants. Key words: Fascioliasis, ELISA

Parenting practices are known to vary across different sociocultural settings, but there has been little scientific research conducted on parenting intervention in Asia to date. Building on our past research achievements that show a strong need for parenting support, we conducted a pilot trial of systematic screening of Vietnamese mothers with poor mental health and the provision of a group-based parenting program, along with staff training sessions at a university-affiliated general hospital in Ho Chi Minh City. Forty-seven first-time mothers attending routine child health checkups were screened using a brief mental health and parenting assessment tool that we had developed and used previously. We then evaluated a group-based parenting program provided for two consecutive days to nine participants. The framework of the Canadian Nobody's Perfect Program, which we had previously adopted and evaluated in a Japanese public health service setting, was used to develop a Vietnamese version. The screening and program were found to be well accepted by both participants and staff and are considered to be feasible for use by public hospital services in Vietnam. The process of program adaptation described and discussed herein may be useful to other health professionals in the Asia-Pacific region undertaking similar initiatives.

International audience; Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) were isolated from the grains of Millettia pachyloba (Leguminosae), together with seven known compounds, 5-methoxybarbigerone (3), calopogoniumisoflavone B (4), durmillone (5), jamaicin (6), ichthynone (7), (-)-pisatin (8) and (-)-rotenone (9). The structures were established from spectroscopic analyses, including mass spectrometry and 2D-NMR. Absolute configuration of 2 was proposed based on that of the known compound (-)-pisatine (8). Compounds 1 and 2 exhibited cytotoxicity against KB cells with IC(50) values of 2.0 and 17.6 µM, respectively.

Two popular hazards in supervised learning of neural networks are local minima and over fitting. Application of the momentum technique dealing with the local optima has proved efficient but it is vulnerable to over fitting. In contrast, deployment of the early stopping technique might overcome the over fitting phenomena but it sometimes terminates into the local minima. This paper proposes a hybrid approach, which is a combination of two processing neurons: momentum and early stopping, to tackle these hazards, aiming at improving the performance of neural networks in terms of both accuracy and processing time in function approximation. Experimental results conducted on various kinds of non-linear functions have demonstrated that the proposed approach is dominant compared with conventional learning approaches.

A case-control study was conducted between July and August 2001 in Ho Chi Minh City to investigate factors associated with having induced abortions among primigravid women aged 16 to 38 years. Interviews were conducted with 87 women undergoing abortion (cases) and 81 pregnant women coming for antenatal care (controls). Multiple logistic regression analysis revealed that older age (odds ratio [OR] = 0.84) and being married (OR = 0.05) decreased the risk of getting unintended pregnancy leading to abortion. Risk factors of obtaining an abortion were not being exposed to family planning promotion on television (OR = 2.28) and not knowing the adverse effects of abortion (OR = 10.26). Descriptive analysis of contraceptive behavior showed that 41% of cases had never used contraceptives and the reason for non-usage was lack of knowledge of any type of contraceptives in 43% of the cases. Additionally, only 24% of cases had discussed about family planning with their partners. Effective contraceptive methods should be promoted among young population, both females and males, and they need to be informed of the consequences of abortion. Television programs might be an effective mode of providing the information.

We conducted this cross-sectional study among 392 Japanese and 294 Vietnamese mothers who attended routine child health visits in a Japanese city and at a tertiary hospital in Vietnam, in order to investigate the prevalence and associated sociodemographic, parenting, and psychological characteristics of low maternal confidence in child rearing among them. All data were collected from medical files in Japan, and from medical files and self-administered questionnaires in Vietnam. The proportion of mothers without secure feeling of confidence in the present study was 22% in Japan and 66% in Vietnam. Significant factors associated with a lack of confidence were first-time motherhood and unintended pregnancy in the Japanese dataset and younger age in the Vietnamese dataset. In both groups, a higher proportion of mothers who lacked confidence reported negative parenting outcomes than did confident mothers. Among the three psychological measurements (mood, self-efficacy and depression), higher self-efficacy was associated independently with a significantly reduced risk of not having confidence in child rearing. These results suggest the importance of developing parenting support programs to help Japanese and Vietnamese mothers, particularly those who are young, first-time mothers or who became pregnant unexpectedly, improve their self-efficacy.