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Despite the extensive use of thin-walled structures, the studies on their behaviours when exposed to extreme thermal environment are relatively scarce. Therefore, this paper aims to present the buckling analysis of thin-walled composite I-beams under thermo-mechanical loads. The thermal effects are investigated for the case of studied beams undergoing a uniform temperature rise through their thickness. The theory is based on the first-order shear deformation thin-walled beam theory with linear variation of displacements in the wall thickness. The governing equations of motion are derived from Hamilton's principle and are solved by series-type solutions with hybrid shape functions. Numerical results are presented to investigate the effects of fibre angle, material distribution, span-to-height's ratio and shear deformation on the critical buckling load and temperature rise. These results for several cases are verified with available references to demonstrate the present beam model’s accuracy.

There has been much interest in developing protein adsorbents using nanostructured particles, which can be engineered porous materials with fine control of the surface and pore structures. A significant challenge in designing porous adsorbents is the high percentage of available binding sites in the pores owing to their large surface areas and interconnected pore networks. In this study, continuing the idea of using porous materials derived from natural polymers toward the goal of sustainable development, porous pectin particles are reported. The template-assisted spray drying method using calcium carbonate (CaCO

High-density submicron-sized FeNi particles prepared by a spray pyrolysis route exhibit high magnetic characteristics and enhance the powder core performance indicated by the improvement of the DC bias characteristic value.

Mục tiêu: Nghiên cứu thực hiện nhằm đánh giá thực trạng sức khỏe tâm thần và một số yếu tố liên quan của sinh viên Trường Đại học Y Hà Nội trực tiếp tham gia chống dịch COVID 19 tại các địa phương năm 2021. Phương pháp nghiên cứu: Nghiên cứu mô tả cắt ngang trên 494 sinh viên học viên. Kết quả nghiên cứu: Tỷ lệ trầm cảm, lo âu, stress trên sinh viên và BSNT tham gia chống dịch COVID-19 lần lượt là 18,8%, 7,6% và 43,3%. Trong đó mức độ stress rất nặng chiếm tỷ lệ tương đối cao với 40 người (8,3%). Các yếu tố ảnh hưởng tới tỷ lệ trầm cảm bao gồm: sinh viên tham gia truy vết, 2 lần tham gia chống dịch, tham gia chống dịch tại Bình Dương, TP. Hồ Chí Minh, thời gian chống dịch trên 60 ngày, nam giới. Kết luận: Tỷ lệ sinh viên tham gia chồng dịch COVID 19 có vấn đề sức khỏe tâm thần tương đối cao, do đó cần có biện pháp hỗ trợ chăm sóc sức khỏe tâm thần cho sinh viên trước, trong và sau khi tham gia chống dịch nói chung và COVID 19 nói riêng.

In this study, graphene oxide was prepared by the modified Hummers method, and then iron oxide nanoparticles were deposited on the surface of graphene oxide by hydrothermal method. After synthesis, these materials were characterized via a number of physical methods: X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM/EDX). The results show that the iron oxide particles were synthesized with nano-size, and the material after modified by graphene oxide still retains the magnetism. These materials continue to be evaluated the for removing methylene blue and Congo red in the water. The results show that the synthesized composite materials can selectively adsorb methylene blue and Congo red, thereby showing the potential application of magnetic composite materials in the field of wastewater treatment.

In this paper, the hydrotalcite Mg-Al/CO3 material was synthesized successfully with an Mg/Al molar ratio of 2:1 by the co-precipitation method. SEM images, XRD patterns and FTIR Spectra and Energy Dispersive X-ray Spectra (EDX) of the material were analyzed. Equilibrium adsorption isotherms and kinetic models of the phosphate adsorption process on the hydrotalcite material Mg-Al/CO3 were investigated. The experimental data were analyzed by Langmuir and Freundlich models of adsorption. The phosphate adsorption on the material was well fitted to both Langmuir and Freundlich isotherms, and the maximum adsorption capacity was found to be 46.95 mg/g with the material sample was calcined at 600oC. The kinetic data obtained at different concentrations have been analyzed using a pseudo-first-order and a pseudo-second-order equation. The experimental data fitted very well with the pseudo-second-order kinetic model.

Preparing spherical and submicron FeNi particles in a simple, rapid, and harmless process is highly desirable for various applications yet severely challenging. Herein, we successfully synthesized the FeNi particles from their metal salts in a relatively low reduction atmosphere using three types of reduction agent, i.e., ethanol, ethylene glycol, and formic acid, via spray pyrolysis. The reduction agents were tested over a concentration range of 0–30 vol%. The type and concentration of reduction agents show a crucial role in the formation of FeNi particles. At higher concentrations (25 vol%), ethanol and ethylene glycol produced smooth and spherical FeNi particles of submicron size, 284 ± 1.6 and 399 ± 1.5 nm respectively, whereas formic acid produced particles with an irregular and Janus shape comprising FeNi and FeO, with a size of 396 ± 1.5 nm. A plausible metal salt reduction mechanism was proposed for the different reduction agents. The reduction agent type not only influences the reduction degree but also particle morphology during synthesis. This finding opens new opportunities to adjust the FeNi particles with respect to varied purposes by manipulating reduction agents.

As one of the civilized centers of the Eastern world, with comprehensive economic, political, and cultural power, China soon spread strong influences outside but directly with the neighboring nations, including Vietnam. One of the ways to spread China's power is based on the business of its own merchants. Due to the changes in historical context, especially the decline of feudal production relations, the risk of invasion of Western colonialism, especially the official invasion of French colonialism since 1858 in Vietnam, the commercial activities of Chinese merchants according to the same characteristics as many previous historical periods have appeared new features bearing the marks of the era. Therefore, researching the mediating role of Chinese merchants in Vietnam during the XVII-XIX centuries will help us to have a more comprehensive view of Vietnam’s history generally and the economic picture of Vietnam, particularly within a fierce historical period.

SummaryLipid metabolism plays a central role in prostate cancer. To date, the major focus on prostate cancer lipid metabolism has centered onde novolipogenesis and lipid uptake with little consideration for how cancer cells access these lipids once they are created or taken up and stored. Patient-derived phosphoproteomics identified adipose triglyceride lipase (ATGL), a previously suspected tumor suppressor, as a CAMKK2-AMPK signaling target that, conversely, promotes castration-resistant prostate cancer (CRPC) progression. Phosphorylation of ATGL increased its lipase activity, cancer cell proliferation, migration, and invasion. Shotgun lipidomics and mass spectrometry imaging demonstrated ATGL’s profound regulation of lipid metabolismin vitroandin vivo, remodeling membrane composition. Inhibition of ATGL induced metabolic plasticity, causing a glycolytic shift that could be exploited therapeutically by co-targeting both metabolic pathways. Together, these data nominate ATGL and intracellular lipolysis as potential therapeutic targets for the treatment of CRPC and provide insights for future combination therapies.

Tán xạ Raman tăng cường bề mặt (SERS) là một kỹ thuật phân tích cho phép phát hiện lượng vết của các phân tử hữu cơ và sinh học. Trong kỹ thuật này, đế SERS, nơi mà tín hiệu tán xạ Raman được tăng cường, đóng vai trò đặc biệt quan trọng. Một trong những loại đế SERS được sử dụng phổ biến nhất là các hạt nano bạc (AgNPs) gắn trên một đế rắn. Thông thường, các mảng AgNPs được chế tạo bằng phương pháp lắng đọng không điện, trong báo cáo này chúng tôi trình bày việc chế tạo các ảng AgNPs trên bề mặt silic bằng phương pháp lắng đọng điện hóa. Kết quả cho thấy, phương pháp này cho phép tạo ra mảng hạt nano bạc đồng đều về kích thước, hình thái cũng như khoảng cách giữa các hạt. Hơn thế nữa, kích thước và khoảng cách giữa các hạt có thể được điều khiển bảng sự thay đổi mật độ dòng điện hóa. Để kiểm tra hiệu suất của các đế SERS, các mảng hạt AgNPs được sử dụng là đế SERS để phát hiện tinh thể tím (CV). Các kết quả chon thấy cường độ của tín hiệu SERS phụ thuộc mạnh vào kích thước của AgNPs và khoảng cách giữa chúng. Với các mảng hạt AgNPs tối ưu, chúng tôi đã ghi nhận được phổ SERS của CV ở nồng độ dưới 0,1 ppb.

The outbreak of the COVID-19 pandemic has strongly influenced teaching and learning in Vietnam’s higher education institutions. Social distancing – the health care practice of increasing the physical space between people to avoid spreading illness due to COVID-19 has required schools to employ distance learning. As such, video conferencing tools (VCTs) have been used nationwide to ensure effective responses to the requirement. Although teaching and learning with VCTs have been proven effective by many researchers, it is not clear what benefits and challenges they bring to higher education in Vietnam, especially with respect to students’ acceptance to the classroom uses of technology in the time of unexpected events. This study aims to address this gap by examining external factors that affected students’ acceptance of VCTs during the COVID pandemic. Data were collected online from university students between April 14, 2020 and April 23, 2020. After this period, the research group received 294 records, in which 227 were analyzed using an extended Technology Acceptance Model (TAM) and Structural Equation Modeling (SEM). The result indicated that external factors such as subject norm and computer playfulness had a significant impact on most TAM constructs. Furthermore, output quality was found to have a positive influence on students’ perceived usefulness in the acceptance of VCTs in distance learning.

Hollow carbon spheres (HCSs) have attracted tremendous interest in recent years due to their intriguing structure-induced physicochemical properties and significant potential for numerous applications. However, the preparation of HCSs with precise structural control using a simple and scalable strategy remains challenging. In this work, hollow carbon particles having a well-defined spherical morphology were successfully produced using a green, economical, and facile spray drying method together with a carbonization process. Kraft lignin was employed as the carbon precursor in place of lignosulfonate with potassium hydroxide (KOH) as an activation agent. The high specific surface area (1536.5–2424.8 m2 g−1) with micro-mesoporous structure of HCSs can be easily tuned by controlling the mass ratio of KOH to carbon precursor. The KOH-to-lignin mass ratios were utilized below 1.5, lower than those in previous studies typically used higher than 3, which was in accordance with green chemistry principles. In addition, these HCSs have applications as electrode materials in supercapacitors for energy storage devices. With the great achievements and continuous efforts in this important field, these results suggest that our approach will open a new path for the development of advanced carbon materials and high value-added utilization of Kraft lignin as a promising material for potential applications.

Sea level rise and land subsidence — induced flooding are projected to have severe impacts on highly populated Asian deltaic cities. These cities are already suffering from frequent floods, though few comparative analyses have been conducted on the similarities and differences of their adaptation approaches. Thus, this study aims to investigate the current adaptation pathways of Asian deltaic cities to flooding induced by slow onset events such as urbanization-induced land subsidence and sea level rise, by looking at Tokyo, Jakarta, Manila, and Ho Chi Minh City as case studies. Evidence from them shows that an engineering approach towards flooding adaptation is shaping the future of Asian deltaic cities. However, emerging challenges question the sustainability of this approach. Recommendations on how to improve current adaptation pathways and direction for future research are also provided.

In this study, we examined the dependence of surface morphology and spin Seebeck effect (SSE) voltages on the poly[vinylpyrrolidone] (PVP) concentration in polycrystalline Y3Fe5O12 (YIG) ultrathin films on a silicon substrate synthesized by metal-organic decomposition followed by a crystallization process. During fabrication, PVP concentrations of 0.5–2 g were used while all other conditions remained fixed. Atomic force microscopy and grazing incidence X-ray diffraction (XRD) measurements revealed a strong dependence of crystallinity and sample morphology on PVP concentration. The 1-g PVP sample had the smoothest surface, with a root mean square roughness of 0.2 nm, as well as superior bulk uniformity with respect to the shape and intensity of XRD reflection peaks. This was confirmed by scanning electron microscopy measurements of a cross-section of the sample that revealed a uniform film without pores. SSE measurements were performed to obtain the output SSE voltages (VSSE) of all samples, to which a platinum layer was added as a spin-detection layer. Repeatedly, the 1-g PVP sample had the best performance, demonstrating the importance of film crystallinity and morphology in the spin-to-charge conversion efficiency of YIG films.

The short form of the Experiences in Close Relationships Scale–Revised Child version (ECR-RC) is a promising self-report measure of anxious and avoidant attachment in Western adolescents, yet little is known about its psychometric properties across cultures. More importantly, little is known about attachment styles across cultures, child gender, and parental gender. The present study aims to address these limitations by studying the psychometric properties and measurement invariance of the ECR-RC in a sample of 1,232 Belgian and Vietnamese adolescents (45.9% boys, Mage = 12.3, SD = 1.20, range = 9.0–15.0; 61.36% Vietnamese adolescents). Results indicated that the factor structure of the mother-oriented ECR-RC was replicated across a Belgian and a Vietnamese sample and that the scale was invariant across both cultures and across gender and age. Vietnamese adolescents were more avoidantly and anxiously attached to their mothers compared to their Belgian counterparts. Boys were more avoidantly and anxiously attached compared to girls for the total sample. Considering two countries separately, boys were found to be more avoidantly attached, not anxiously attached compared to girls. Furthermore, with increasing age, more anxious and avoidant attachment was reported, except in Belgian adolescents where anxious and avoidant attachment did not differ over age. Focusing solely on the Vietnamese data, results revealed that the ECRRC is a reliable measure to assess Vietnamese adolescents’ anxious and avoidant attachment to both parents. Vietnamese adolescents did not differ in their levels of anxious attachment toward both parents but showed higher avoidant attachment to fathers compared to mothers.

Asperspiropene A was originally reported to have a unique 1,8-dioxaspiro[4.5]decane skeleton. During the course of our ongoing research for novel marine natural products, we isolated compound 1, which has identical 1D and 2D NMR data to asperspiropene A. Detailed and careful analysis of spectroscopic data led us to revise the structure of asperspiropene A and to determine its absolute configuration.

Recently, the inherent piezoelectric properties of the 2D transition-metal dichalcogenides (TMDs) tin monosulfide (SnS) and tin disulfide (SnS2) have attracted much attention. Thus the piezoelectricity of these materials has been theoretically and experimentally investigated for energy-harvesting devices. However, the piezoelectric output performance of the SnS2- or SnS-based 2D thin film piezoelectric nanogenerator (PENG) is still relatively low, and the fabrication process is not suitable for practical applications. Here we report the formation of the SnS2/SnS heterostructure thin film for the enhanced output performance of a PENG using atomic layer deposition (ALD). The piezoelectric response of the heterostructure thin film was increased by ∼40% compared with that of the SnS2 thin film, attributed to large band offset induced by the heterojunction formation. Consequently, the output voltage and current density of the heterostructure PENG were 60 mV and 11.4 nA/cm2 at 0.6% tensile strain, respectively. In addition, thickness-controllable large-area uniform thin-film deposition via ALD ensures that the reproducible output performance is achieved and that the output density can be lithographically adjusted depending on the applications. Therefore, the SnS2/SnS heterostructure PENG fabricated in this work can be employed to develop a flexible energy-harvesting device or an attachable self-powered sensor for monitoring pulse and human body movement.

This study aims to evaluate the expression level of autophagy genes during the activation of mouse hepatic stellate cells (HSCs) in vitro. The HSCs isolated from the mouse liver were cultured in vitro for 7 days. The activation of HSCs was evaluated by their morphology, the storage of lipid droplets by oil red O (ORO) staining, the expression of activation-related genes α-sma, collagen I, and quiescence-related gene lrat by qRT PCR and ICC staining (α-SMA). The expression of autophagy genes lc3b, beclin 1, atg12 were assessed by qRT PCR and ICC staining (LC3). The results showed that the isolated HSCs were activated after 3 days and 7 days of the culture in vitro. The activation was indicated by the morphological change of HSCs to myofibroblast-like cells, loss of lipid droplets, and increased expression of fibrotic genes α-sma and collagen I, decreased expression of lrat. Additionally, the expression of autophagy genes lc3b, beclin 1, and atg12 were significantly increased in the activated HSCs after the culture in vitrofor 3 and 7 days. This study contributes the preliminary results to further studies on the role of autophagy during the activation of HSCs, which may be exploited for the development of the antifibrotic therapy targeting autophagy.

Aims Myocardial infarction (MI) accelerates atherosclerosis and greatly increases the risk of recurrent cardiovascular events for many years, in particular, strokes and MIs. Because B cell-derived autoantibodies produced in response to MI also persist for years, we investigated the role of B cells in adaptive immune responses to MI. Methods and results We used an apolipoprotein-E-deficient (ApoE−/−) mouse model of MI-accelerated atherosclerosis to assess the importance of B cells. One week after inducing MI in atherosclerotic mice, we depleted B cells using an anti-CD20 antibody. This treatment prevented subsequent immunoglobulin G accumulation in plaques and MI-induced accelerated atherosclerosis. In gain of function experiments, we purified spleen B cells from mice 1 week after inducing MI and transferred these cells into atherosclerotic ApoE−/− mice, which greatly increased immunoglobulin G (IgG) accumulation in plaque and accelerated atherosclerosis. These B cells expressed many cytokines that promote humoural immunity and in addition, they formed germinal centres within the spleen where they differentiated into antibody-producing plasma cells. Specifically deleting Blimp-1 in B cells, the transcriptional regulator that drives their terminal differentiation into antibody-producing plasma cells prevented MI-accelerated atherosclerosis. Alarmins released from infarcted hearts were responsible for activating B cells via toll-like receptors and deleting MyD88, the canonical adaptor protein for inflammatory signalling downstream of toll-like receptors, prevented B-cell activation and MI-accelerated atherosclerosis. Conclusion Our data implicate early B-cell activation and autoantibodies as a central cause for accelerated atherosclerosis post-MI and identifies novel therapeutic strategies towards preventing recurrent cardiovascular events such as MI and stroke.

Trong báo cáo này chúng tôi trình bày các kết quả bước đầu về việc sử dụng các hạt nano bạc (AgNPs) lắng đọng trên lớp silic cacbua xốp (PSiC) cho việc phát hiện dấu vết của malachite green (MG) sử dụng hiệu ứng tán xạ Raman tăng cường bề mặt (SERS). Cụ thể hơn, các đế SERS được chế tạo từ AgNPs lắng đọng trên bề mặt của lớp silic cacbua vô định hình xốp (AgNPs@PSiC). Các kết quả cho thấy sự thay đổi trong cấu trúc của lớp PSiC và/hoặc AgNPs ảnh hưởng tới chỉ số tăng cường Raman của các đế SERS. Với đế AgNPs@PSiC tốt nhất, hàm lượng MG thấp tới 10-9 M có thể phát hiện được.

A green synthetic strategy to design biomass-derived porous carbon electrode materials with precisely tailored structure and morphology has always been a challenging goal because these materials can fulfill the demands of next-generation supercapacitors and other electrochemical devices. Potassium hydroxide (KOH) is extensively utilized as an activator since it can produce porous carbon with high specific surface area and well-developed porous channels. The exploitation of sodium hydroxide (NaOH) as an activating agent is less referenced in the literature, although it offers some advantages over KOH in terms of low cost, less corrosiveness, and simple handling procedure, all of which are appealing particularly from an industrial viewpoint. The motivation for this present study is to fabricate porous carbon spheres in a sustainable manner via a spray drying approach followed by a carbonization process, using Kraft lignin as the carbon precursor and NaOH as an alternative activation agent instead of the high-cost and high-corrosive KOH for the first time. The structure of carbon particles can be accurately transitioned from a compact to hollow structure, and the surface textural properties can be easily tuned by altering the NaOH concentration. The obtained porous carbon spheres were applied as highly packed thin film electrode materials for supercapacitor devices. The specific capacitance value of porous carbon spheres with a highly compact structure (high packing density) is 66.5 F g

International audience; Benzothiazine S,S-dioxides 2 were synthesized by simply heating o-nitrostyrenes with elemental sulfur in 3-picoline with complete atom economy. This reaction was found to occur without any added catalyst and consist of a cascade of reduction of the nitro group, sulfuration of a C-H of the double bond, oxidation of a sulfur atom to its highest oxidation state by the migration of two oxygen atoms from the nitro group and formation of new N-S bond. Furthermore, the method could also be applied to o-nitrocinnamamides and cinnamate esters.

Background Multiple studies have reported on the accuracy of the prognostic 31-gene expression profile test for cutaneous melanoma. Consistency of the test results across studies has not been systematically evaluated. Objective To assess the robustness of the prognostic value of the 31-gene expression profile. Methods Raw data were obtained from studies identified from systematic review. A meta-analysis was performed to determine overall effect of the 31-gene expression profile. Clinical outcome metrics for the 31-gene expression profile were compared with American Joint Committee on Cancer staging. Results Three studies met inclusion criteria; data from a novel cohort of 211 patients were included (n = 1,479). Five-year recurrence-free and distant metastasis-free survival rates were 91.4% and 94.1% for Class 1A patients and 43.6% and 55.5% for Class 2B patients (P Conclusion The 31-gene expression profile test consistently and accurately identifies melanoma patients at increased risk of metastasis, is independent of other clinicopathologic covariates, and augments current risk stratification by reclassifying patients for heightened surveillance who were previously designated as being at low risk.

This article examines the different kinds of illegal logging that takes place in Vietnam, challenging the typical approaches to understanding and classifying the various criminal activities involved. We argue that either overlooking the classification of illegal logging or relying solely on illegal timber volumes and legal descriptions to categorise the crime is not sufficient to comprehend its diverse nature. This leads to inappropriate measures to tackle the crime. Instead, this study suggests that illegal logging should be categorised into three types, which are fundamentally distinctive, not only with regard to the volumes of illicit timber and the legislative definitions of the crime, but also (and more importantly) with reference to the attributes of harvesters, the degree of their involvement and their motivations, and the level of organisation involved in criminal commissions.

Hollow silica particles are desirable for numerous applications, however, designing hollow silica materials with varying hollow structures and shapes remains a significant challenge. Herein, a strategy for the precisely controlled synthesis of hexagonal-shaped hollow silica plate (HHSP) particles was successfully prepared via a sol-gel method at room temperature, using tetraethyl orthosilicate (TEOS) as a silica precursor and zinc oxide (ZnO) particles as a colloidal template. The effect of reaction time was carried out to control the structure and morphology of HHSP particles, and the thickness of silica shell can be tuned in the range from 12.2 to 43.2 nm by adjusting the TEOS/ZnO molar ratios. In addition, the polymer/HHSP composite thin films were prepared using poly(methyl methacrylate) (PMMA) matrix and surface modified HHSP particles by grafting silane coupling agents. High transmittance values were observed (>95%) for the composite thin films (5 μm in thickness, 0.1–1.0 wt% HHSP) in the ultraviolet and visible regions. Furthermore, the refractive index of HHSP particles was observed to be 1.28, which is significantly lower than dense silica (n = 1.46). These results suggest that the approach adopted herein will open up opportunities for the development of a new generation of film materials with a low refractive index.

Past studies have projected that global mean sea levels could be up to between 0.98 and 2.92 m higher by the year 2100 than pre-industrial levels, which could seriously affect wastewater treatment plants (WWTPs). However, there is currently a lack of guidelines regarding how these types of installations can adapt to sea level rise (SLR). The present research analyzes how SLR might affect WWTPs that are situated near the coastline and how they can adapt by using experiences of land subsidence as a proxy. The Tohoku region in northern Japan experienced severe land subsidence (up to − 1.14 m in Ishinomaki city) after the 2011 Tohoku earthquake. The authors conducted in-depth interviews with staff from three significant WWTPs in the area to elucidate the effects that land subsidence had on their operations and how they could adapt to an increase in land subsidence or SLR. The results suggest that for land subsidence of − 0.53 m (equivalent to a SLR of + 0.53 m), the surveyed WWTPs were considered to be able to operate normally, without undertaking any major adaptation actions. Critical levels that influence the vulnerability and adaptation strategies of WWTPs to SLR were identified. These critical levels can help differentiate between the three types of SLR-induced flooding that can affect the plants, namely coastal flooding, discharge flooding and groundwater inundation. WWTPs utilizing combined sewage systems may face more difficulties when adapting to SLR. Finally, the authors proposed limit-state adaptation pathways for WWTPs situated in low-lying coastal areas, including a sequence of possible countermeasures and a timeline for specific actions to take place.