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Duc Trong Quach,1 Binh Thanh Phan2 1Department of Internal Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh, Vietnam; 2Department of Internal Medicine, Moc-Hoa Regional General Hospital, Long An, VietnamCorrespondence: Duc Trong Quach, Department of Internal Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, 217 Hong Bang Street, District 5, Ho Chi Minh, Vietnam, Tel +84-8-38554269, Fax +84-8-39506126, Email drquachtd@gmail.comPurpose: Depression is more prevalent in patients with gastroesophageal reflux disease (GERD) than in controls. The disorder can worsen the quality of life of GERD patients and is also associated with poor treatment response. However, there are limited data on its prevalence and risk factors in GERD patients in Southeast Asia. We aimed to assess the prevalence and severity of depression and its associated factors in Vietnamese patients with GERD.Patients and methods: A cross-sectional study was conducted on GERD patients. GERD was defined as troublesome typical reflux symptoms at least twice a week or having endoscopic erosive reflux disease. The revised Beck’s Depression Inventory (BDI-IA), which has been locally validated, was used to evaluate depression (BDI-IA < 10: none, 10– 18: mild to moderate, 19– 29: moderate to severe, and ≥ 30: severe depression). Multiple logistic regression analysis was used to identify independent factors associated with depression.Results: A total of 194 patients were recruited. The mean age was 44.1 ± 12.0 years, and the male-to-female ratio was 1:1.2. The depression rate was 47.9% (mild to moderate: 30.9%, moderate to severe: 16.0%, and severe: 1.0%). In multivariate analysis, sex and duration of reflux symptoms were the only two risk factors for depression. Compared to males, females were more likely to suffer from depression: odds ratio (OR) = 3.941 (95% confidence interval [CI], 1.386– 11.205), p = 0.010. Compared to patients with a duration of reflux symptoms < 1 year, those with a duration of 1– 10 years and > 10 years were more likely to suffer from depression with a dose‒response: OR = 3.520 (95% CI, 1.057– 11.717), p = 0.040; and OR = 5.605 (1.046– 30.019), p = 0.044, respectively.Conclusion: Depression was prevalent, and a long duration of reflux symptoms was its predominant risk factor in Vietnamese patients with GERD.Keywords: gastroesophageal reflux disease, depression, prevalence, Vietnam

The postharvest preservation of Ngoc Linh ginseng (NL ginseng) is essential to retain its quality and sensory values for prolonged storage. In this study, the efficacy of NL ginseng preservation by coating chitosan derivatives in combination with polyvinyl alcohol (PVA) solutions was investigated under refrigeration conditions (~3 °C; ~40% RH) for 56 days. The effect of the chitosan-based solutions, including N,O-carboxymethyl chitosan (NOCC), chitosan oligomer saccharide (COS), or chitosan (CS), and the blend solutions (NOCC-PVA or COS-PVA) on the coated NL ginsengs was observed during storage. The pH values, viscosity, and film-forming capability of the coating solutions were determined, while the visual appearance, morphology, and mechanical properties of the films formed on glass substrates as a ginseng model for coating were also observed. The appearance, skin lightness, weight loss, sensory evaluation, total saponin content (TSC), total polyphenol content (TPC), and total antioxidant capacity (TAC) of the coated NL ginsengs were evaluated. The findings showed that the observed values of the coated NL ginsengs were better than those of the non-coated samples, with the exception of the COS-coated samples, which had completely negative results. Furthermore, the NOCC-PVA solution exhibited a better preservation effect compared with the COS-PVA one based on the observed indices, except for TPC and TAC, which were not impacted by the coating. Notably, the optimal preservation time was determined to be 35 days. This study presents promising preservation technology using the coating solution of NOCC-PVA, harnessing the synergistic effect of pH 7.4 and the form-firming capacity, to maintain the shelf life, medicinal content, and sensory attributes of NL ginseng.

Plasmonic sensors have broad application potential in many fields and are promising to replace most bulky sensors in the future. There are various method-based chemical reduction processes for silver nanoparticle production with flexible structural shapes due to their simplicity and rapidity in nanoparticle fabrication. In this study, self-assembled silver nanoparticles (Ag NPs) with a plasmon peak at 424 nm were successfully coated onto -NH 2 -functionalized glass and optical fiber sensors. These coatings were rapidly produced via two denaturation reactions in plasma oxygen, respectively, and an APTES ((3-aminopropyl)triethoxysilane) solution was shown to have high strength and uniformity. With the use of Ag NPs for surface-enhanced Raman scattering (SERS), excellent results and good stability with the detection limit up to 10 -10 M for rhodamine B and 10 -8 M for methylene blue, and a signal degradation of only ∼20% after storing for 30 days were achieved. In addition, the optical fiber sensor with Ag NP coatings exhibited a higher sensitivity value of 250 times than without coatings to the glycerol solution. Therefore, significant enhancement of these ultrasensitive sensors demonstrates promising alternatives to cumbersome tests of dye chemicals and biomolecules without any complicated process., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Copper chalcogenide Cu 2 (Se,Te) compounds are well known as typical p-type thermoelectric materials with a figure of merit ( ZT ) that can be optimized by the ratio of Se : Te. Here, by using the mechanical alloying and solid-state reaction methods, Te was substituted into Se sites within Cu 2 Se as the formula Cu 2 Se 1- x Te x ( x = 0.1, 0.2, 0.25, and 0.3). The observed changes in structural phase, grain morphologies, and grain size were recorded by XRD and FE-SEM imaging with the appearance of the secondary phase of Cu 2 Te, with a Te content of x = 0.25. The layered structure morphology was observed more clearly at the high Te content. The electrical conductivity was greatly increased with enriched Te content while the maximum Seebeck coefficient was obtained in the Cu 2 Se 0.75 Te 0.25 sample. Accordingly, a power factor value of up to 9.84 μW cm -1 K -2 at 773 K was achieved. The appearance of a Cu 2 Te phase with a Te content of 0.25 created a structural phase transition which results in a ZT value of 1.35 at 773 K in the Cu 2 Se 0.75 Te 0.25 sample., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Here, we report the highly active and selective electrocatalytic reduction of NO 2 - ions to value-added NH 3 over a single-atom Ru-modified Cu nanowire array on three-dimensional copper foam (Ru-Cu NW/CF) under ambient conditions. The obtained Ru-Cu NW/CF catalyst exhibited a maximum faradaic efficiency of 94.1% and an NH 3 yield up to 211.73 mg h -1 cm -2 (0.732 mmol h -1 cm -2 ), which was approximately five times higher than that of the Cu NW/CF catalyst.

TiO 2 is a well-known semiconductor used widely in the photocatalyst field, but its photocatalytic applications are hampered by a fast electron-hole recombination rate and low visible light absorption due to a wide-band-gap energy. Herein, we present a simple, low cost, and green approach to obtain carbon dots from microalgae, namely microalgae-based carbon dots (MCDs), using an unprecedented microwave-assisted treatment. The MCDs were successfully decorated on the surface of TiO 2 nanoparticles. The as-prepared composite exhibited a superior photodegradation of methylene blue, compared with pristine TiO 2 (83% and 27%, respectively) under visible light irradiation. The MCDs in TiO 2 -MCDs serve as electron reservoirs to trap photoinduced electrons and as photosensitizers for the improvement of visible light absorption; both factors play an important role in the improvement of the TiO 2 photocatalytic activity. Furthermore, the as-prepared composite photocatalyst also exhibits high photostability and recyclability during the photodegradation of methylene blue. Therefore, this work provides an original approach to the development of environmentally friendly and highly effective photocatalysts for the treatment of various organic pollutants, which can go a long way toward ensuring a safe and sustainable environment., (Copyright © 2022 Elsevier Inc. All rights reserved.)

We investigated the coupling phenomenon between plasmonic resonance and waveguide modes through theoretical and experimental parametric analyses on the bimetallic waveguide-coupled long-range surface plasmon resonance (Bi-WCLRSPR) structure. The calculation results indicated that the multi-plasmonic coupling gives rise to the enhanced depth-to-width ratio of the reflection dip compared to that of LRSPR excited using a single set of Ag and Teflon. The optimized thickness of Ag(40 nm)/Teflon(700 nm)/Ag(5 nm)/Au(5 nm) was obtained and generated the highest plasmon intensity enhancement, which was 2.38 folds in comparison to the conventional bimetallic surface plasmon resonance (SPR) configuration (Ag/Au). 17β-Estradiol was used in the fluorescence enhancement experiment by the reflection geometry-based system, wherein the excitation light source was on the side of a WC-LRSPR chip opposite to that of the light detection unit. The phenomenon of surface plasmon-couple emission (SPCE) depends on the number of 17β-estradiol molecule promoters from female sex steroid hormones, which demonstrated a limit of detection (LOD) of 2 pg mL -1 and 1.47-fold fluorescence improvement as compared to the non-coated material on the surface of pristine glass. This enhanced WC-LRSPR can readily find application in fluorescence escalation needed in cases where a weak fluorescence signal is predicted, such as the small volume of liquid containing fluorescent dyes in biological diagnosis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Measuring solution concentration plays an important role in chemical, biochemical, clinical diagnosis, environmental monitoring, and biological analyses. In this work, we develop a transmission-mode localized surface plasmon resonance sensor chip system and convenient method which is highly efficient, highly sensitive for detection sensing using multimode fiber. The plasmonically active sensor's surface AuNPs with high-density NPs were decorated onto 1 cm sensing length of various clad-free fiber in the form of homogeneous monolayer utilizing a self-assembly process for immobilization of the target molecule. The carboxyl bond is formed through a functional reaction on the sensor head. Using the significance in the refractive index difference and numerical aperture, which is caused by a variation in the concentration of measuring bovine serum albumin (BSA) protein which can be accurately measured by the output signal. The refractive index variation of the medium analyte layer can be converted to signal output power change at the He-Ne wavelength of 632.8 nm. The sensor detection limit was estimated to be 0.075 ng ml -1 for BSA protein which shows high sensitivity compared to other types of label-free optical biosensors. This also leads to a possibility of finding the improvement in the sensitivity label-free biosensors. The conventional method should allow multimode fiber biosensors to become a possible replacement for conventional biosensing techniques based on fluorescence., (© 2021 IOP Publishing Ltd.)

This paper presents an efficient, environmentally friendly, and simple approach for the green synthesis of ZnO nanoparticles (ZnO NPs) using orange fruit peel extract. This approach aims to both minimize the use of toxic chemicals in nanoparticle fabrication and enhance the antibacterial activity and biomedical applications of ZnO nanoparticles. In this work, an aqueous extract of orange peel was used as the biological reduction agent for the synthesis of ZnO NPs from zinc acetate dihydrate. It was found that the size and morphology of the ZnO NPs significantly depended on physicochemical parameters such as the annealing temperature and pH during NP synthesis. The ZnO NPs exhibited strong antibacterial activity toward Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) without UV illumination at an NP concentration of 0.025 mg mL -1 after 8 h of incubation. In particular, the bactericidal activity towards S. aureus varied extensively with the synthesis parameters. This study presents an efficient green synthesis route for ZnO NPs with a wide range of potential applications, especially in the biomedical field., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

The gas sensing properties of two novel series of Mg-incorporated metal-organic frameworks (MOFs), termed Mg-MOFs-I and -II, were assessed. The synthesized iso-reticular type Mg-MOFs exhibited good crystallinity, high thermal stability, needle-shape morphology and high surface area (up to 2900 m 2 ·g -1 ), which are promising for gas sensing applications. Gas-sensing studies of gas sensors fabricated from Mg-MOFs-II revealed better sensing performance, in terms of the sensor dynamics and sensor response, at an optimal operating temperature of 200 °C. The MOF gas sensor with a larger pore size and volume showed shorter response and recovery times, demonstrating the importance of the pore size and volume on the kinetic properties of MOF-based gas sensors. The gas-sensing results obtained in this study highlight the potential of Mg-MOFs gas sensors for the practical monitoring of toxic gases in a range of environments.

In this paper, we surveyed the effect of the concentration of AgNO₃ solution and the time of photoreduction on the formation of Ag nanoparticles supported on TiO₂ nanotubes (Ag/TNTs) were synthesized by photoreduction method. Their morphology and crystal structure were determined by Transmission Electron Microscopy images (TEM), X-ray Diffraction (XRD) and Energy-dispersive X-ray spectroscopy (EDX) data. Results show that the amount of Ag nanoparticles supported on TNTs could be controlled by changing of the illumination time (photoreduction time) and the concentration of AgNO₃ solution. Besides, the annealing temperature has a direct influence on the morphology of TNTs. Especially, the nanotubes transformed into nanorods at 500 °C for 2 hours.

TiO2 nanotubes (TNTs) were synthesized by a hydrothermal method from commercial TiO2 in NaOH followed by HCl washing. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmitting electron microscopy (TEM), and Brunauer-Emmet-Teller (BET) measurements. The untreated acid samples (pH ~ 12) don't appear nanotubes structure, while acid-treated samples until the pH reached around 2 have approximate diameters of nanotubes of 10 nm. The samples reaction temperature at 135 °C appear nanotubes structure while the samples reaction temperature at 150 °C have combination of the nanotubes and the samples treatment temperature at 170 °C appear both nanotubes structure and particles clumping together. The surface area of the TNTs was 83,5 m2/g while the surface area of commercial TiO2 particles was 41 m2/g.

Following the inclusion of mifepristone + misoprostol for early pregnancy termination into the Vietnam National Reproductive Health Guidelines in 2002, a team from the Ministry of Health, World Health Organization and Ipas assessed how best to move from clinical research to widespread public sector availability. After field visits to hospitals and discussions with stakeholders, the team endorsed the phased introduction of medical abortion alongside vacuum aspiration services to expand choice. They stressed the importance of patient-oriented information on what to expect as the abortion process takes place and the need for follow-up, also crucial in training of providers. Routine use of ultrasound to detect ectopic pregnancies or determine that abortion was complete was considered unnecessary The mandated four-hour observation period following misoprostol administration could be reduced. The National Guidelines, appropriately conservative at the start of the programme, should be amenable to modification as experience grows. Introduction is not possible without a steady supply of drugs at affordable prices. Ways to reduce the high price of mifepristone and deal with provider expectations of extra allowances, as with surgical abortion, are needed. Making medical abortion a viable option for most Vietnamese women will require provision at commune-level clinics through mid-level providers, and with home use an option. Other challenges include use of misoprostol alone and regulating provision in the private sector.