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Recently, the assembly of van der Waals heterostructures (vdWH) has proved to be an effective strategy to alter the properties and enhance the functionality of multifunctional devices based on 2D materials. Herein, first‐principles calculations are employed to construct the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH, exploring its electronic properties, contact characteristics, and the impact of electric gating. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH is predicted to be structurally, thermally, and mechanically stable. The HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH leads to a reduction in the bandgap compared to the constituent components, potentially enhancing optical absorption. Furthermore, the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure forms the type‐II band alignment, localizing electrons and holes predominantly in the HfS2${\rm HfS}_2$ and MoS2${\rm MoS}_2$ layers, respectively. Such type‐II HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ heterostructure makes it promising candidate for the optoelectronic devices, benefiting from the spatial separation of photogenerated electron‐hole pairs. Notably, the electronic properties and contact characteristics of the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH are controllable under electric gating. The negative electric gating facilitates to a transformation from type‐II to type‐I band alignment, while the positive electric field induces a shift from semiconductor to metal in the HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH. This findings can provide valuable insights into the fundamental aspects that contribute to the exceptional performance observed in HfS2${\rm HfS}_2$/MoS2${\rm MoS}_2$ vdWH toward high‐performance multifunctional devices. [ABSTRACT FROM AUTHOR]

The ascribed work suggests a fabrication pathway of carbon aerogel material from the rose apple (Syzygium jambos) fruit (RACA), in which a hydrothermal step, followed by a calcination process under various temperatures from 600 to 900 °C was carried out. RACA were characterized via multiple methods to briefly determine the optimal calcination temperature for the application, revealing that the temperature of 700 °C provided an intermediate deconstruction effect to form the amorphous structure and amplified the surface area. Whence, the materials were assessed for the adsorption capacities towards diesel oil which provided a capacity of approximately 35 g/g, although the adsorption capacity decreased slightly after 5 cycles of recovery and reuse. Furthermore, RACA‐700 exhibits high adsorption capacity of organic solvents (toluene, cyclohexane, butanol, hexane, and chloroform) and the ciprofloxacin antibiotic. Besides, the utilization of the fabricated carbon aerogel in the supercapacitor was also investigated. The obtained results elucidate the highest specific capacitance of 61.20 F/g, corresponding with the lowest resistance of 195.6 Ω, which indicates the ability to maintain capacitance after 5000 cycles and still retain 60 % efficiency, thereby signifying the potential application of carbon aerogel in sustainable material construction. [ABSTRACT FROM AUTHOR]

This letter presents a touch‐driven self‐powered sensing system utilizing a high‐performance thermoelectric generator (TEG). The TEG, employing assembly technology with a high‐performance electrodeposited thermoelectric material, is fabricated. This device is accompanied by an investigation into the associated electronic circuits, facilitating a realistic demonstration. Upon tactile interaction with one side of the TEG, the system efficiently harvests energy, accumulating 15.36 mJ in a storage capacitor. Energy consumption, inclusive sensors and Bluetooth Low Energy (BLE) communication, is evaluated at 0.75 mJ/cycle, with a 2 s interval time. Notably, the sensing system demonstrates sustained operation as long as touch interactions persist, showcasing its potential for continuous, self‐powered functionality. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The disposal of plastic foam, mostly composed of polystyrene, poses significant environmental challenges due to its high popularity, slow degradation, and low cost. To address this problem, recycling polystyrene foam waste (PF) has emerged as a promising solution to reduce plastic pollution. This paper presents a novel approach to mass‐produce highly ordered, porous honeycomb‐patterned film (hc‐film) using wasted PF as the raw material. The hc‐film is produced using an improved phase separation (IPS) method that utilizes methanol as a suitable pore inducer and template droplet stabilizer. Methanol provides the hc‐film with customizable features such as pore ordering, size, and separation. The freestanding hc‐film, achieved by adopting a water‐soluble polystyrene sulfonate as a scarified layer, can be transferred and utilized as a flexible mold to pattern various solid substrates with complicated surface morphologies using the pre‐impregnated technique. This study demonstrates the potential of this cost‐effective and efficient approach for various applications, such as super/anti‐wetting surfaces, microelectronics, optical devices, sensors, and nanogenerators. [ABSTRACT FROM AUTHOR]

BACKGROUND: Following the trend of green and sustainable development, multi‐application materials utilizing biomass waste have been developed, leading that trend is carbon aerogel (CA). In this study, zinc oxide‐doped CA was synthesized from bagasse cellulose (Zn‐BCA) through simple processes: Cross‐linking to form a sol–gel system, freeze‐drying, and pyrolysis. To synthesize suitable materials, precursor and crosslinking ratios, the content of Zn2+, and pyrolysis temperature in N2 were investigated. The characteristics of ZnO were investigated through modern methods: Scanning electron microscopy, Raman spectroscopy, X‐ray diffraction, Fourier‐transform infrared spectroscopy, and energy‐dispersive X‐ray spectroscopy. The dye adsorption capacity of Zn‐BCA was evaluated through the UV–Vis method. Furthermore, the electrochemical properties are shown through cyclic voltammetry, galvanostatic charge‐discharge, electrochemical impedance spectroscopy results, and glucose sensing results were obtained through linear sweep voltammetry. RESULTS: Zn‐BCA shows potential for multiple applications with crystal violet pigment adsorption capacity up to 39 mg/g, specific capacitance reaching 164 F/g, and glucose sensing capabilities. CONCLUSION: Thus, Zn‐BCA shows wide applicability in adsorbents and electrode materials, in addition to using bagasse biomass as green precursor to synthesize materials. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Recently, by forming a P‐rich P–S system, the P3S monolayer has been predicted to have good resistance to air oxidation, large band gap, high absorption, and superior mobility. Inheriting this prediction, a series of ternary Janus P6XY (X/Y = S, Se, and Te; X ≠ Y) monolayers based on P3X nanosheet are designed and studied. The structures of P6XY monolayers are confirmed to be stable based on the evaluation of calculated results for phonon spectra, ab initio molecular dynamic simulations. It is also found that P6XY compounds possess anisotropic mechanical characteristics. All Janus structures are indirect semiconductors with large energy gaps varying from 2.12 to 2.60 eV calculated by the hybrid functional. Besides, biaxial strain significantly affects the electronic properties of the P6XY monolayers. In particular, the biaxial strains can induce a transition from indirect to direct bandgap in all three P6XY structures. The carrier mobility in the three proposed structures exhibits directional anisotropy and high electron mobility value, up to 1.27 × 103 cm2 V−1 s−1, which are suitable for applications in high‐performance and direction‐dependent nanoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, the Garcinia mangostana pericarp aqueous extract was utilized as an efficient reducing agent for the phyto‐synthesis of eco‐friendly silver nanoparticles (GM/AgNPs (GMAs)). Characterization of the as‐synthesized material revealed the optimal synthesis conditions of 1 mL of the extract, 1.6 mL of AgNO3, and 1 mL of pH 10 buffer solution at 70 °C for 30 min of reaction. The formation and distribution of quasi‐spherical silver nanoparticles were elucidated with an average particle size of 22.12±1.106 nm, whilst the colloidal system of GMAs also possessed a negative surface charge (−25.4 mV) with such low particle instability parameters (PIP), signifying great stability even after 8 weeks. Furthermore, the material demonstrated excellent bioactivities, wherein a good inhibitory was acquired towards both P. aeruginosa and S. aureus. Besides, the synthesized GMAs provided great catalytic reduction performances, which removed 98.75, 96.55, and 90.85 % of RhB, MO, and 4‐NP, respectively, within 120 s. Along with a low detection limit for surveyed heavy metal ions as well as H2O2 in specific concentration ranges, the phyto‐synthesized GMAs can be efficaciously employed in a wide range of environmental applications, namely in the medical and wastewater remediation sectors. [ABSTRACT FROM AUTHOR]

The increase in the number of infectious diseases has exerted many negative consequences on human health. In this study, the antibacterial cotton fabric was fabricated for application in antibacterial products, contributing to the prevention of infectious diseases for humans. Particularly, ex‐situ and in‐situ dip‐coating techniques were compared and utilized for the fabrication of the antibacterial cotton fabric. Besides, the effects of the concentrations of precursors, including graphene oxide (GO), silver nanoparticles (AgNPs), silver/graphene oxide nanocomposite (Ag/GO), and dip‐coating times were evaluated to determine the most appropriate preparation conditions. Therewithal, the resulting cotton fabric was modified with stearic acid (SA) to enhance the hydrophobicity, in which the concentration of the SA was also assessed. Additionally, the antibacterial performance of the prepared material was investigated against Gram‐negative Pseudomonas aeruginosa and Gram‐positive Staphylococcus aureus. Different analytical techniques such as scanning electron microscope, contact angle measurement, and color stability were also utilized for the comparison between different cotton fabrics. According to the obtained results, the dip‐coated in‐situ Ag/GO (in‐situ‐Ag/GO/cotton) fabrics showed better antibacterial performance than that of dip‐coated ex‐situ Ag/GO (ex‐situ‐Ag/GO/cotton) ones, which can be attributed to the even distribution of Ag/GO nanocomposite on the fabric prepared by the in‐situ methods. According to the aforementioned results, the resulting antibacterial cotton fabric can be considered a promising material for the production of antibacterial face masks and protective clothing, which can be utilized in hospitals, textile industries, or the manufacture of sport gears. [ABSTRACT FROM AUTHOR]

Recently, though graphene oxide (GO) has shown promising applications in many fields, there have not been many studies focusing on exploiting the source of synthetic precursors of GO. Herein, GO was synthesized from the cellulose of corncob by corncob alkalization, bleaching cellulose, pyrolysis, and improved Hummer's method. It was found that pyrolysis plays an important role in the graphitization of cellulose precursors with the catalyst Fe(NO3)3 to form Gi‐Fe(NO3)3. The GO material synthesized from Gi‐Fe(NO3)3 was characterized by advanced analytical methods. The X‐ray diffraction pattern of Gi‐Fe(NO3)3 shows the formation of a diffraction peak at the crystal plane (002), which is characteristic of the graphite material. The synthesized GO underwent a series of changes in material structure and morphology, which are confirmed via transmission electron microscopy images showing a plate‐like structure with folds represented by the dark line. This study demonstrates a sustainable approach that directly utilizes abundant biomass resources for the synthesis of GO material. [ABSTRACT FROM AUTHOR]

In this study, silver‐titanium dioxide/graphene aerogel (Ag−TiO2/GA−ATG) was synthesized via chemical reduction using ethylene diamine (EDA). The effects of reductant doses on the formation of the three‐dimensional structure and the photocatalytic degradation efficiency of ATG were evaluated with five different volumes (20, 30, 40, 50, and 60 μL), corresponding to the ATG1, ATG2, ATG3, and ATG4, respectively. The results showed that 40 μL of EDA was the suitable condition for the formation of ATG three‐dimensional structure. Characterizations revealed that ATG3 was successfully synthesized with distinctive peaks of Ag and TiO2 in the X‐ray diffraction patterns whilst scanning electron microscope and high resolution transmission electron microscope images showed a porous structure, silver nanoparticles and TiO2 with an average size of 10–25 nm were uniformly distributed on the graphene surface. Furthermore, ATG3 possessed the highest photocatalytic capability to deteriorate methyl orange with an efficiency of up to 99.53 % with a catalyst dose of 0.3 mg/mL, superior compared to those of TiO2 and TiO2/GA. The radicals scavenging experiments elucidated ⋅O2 ${{{\rm { O}}}_{{\rm { 2}}}^{{\rm { \char60 M-\char62 }}}}$ to majorly contribute to the photodegradation process. Moreover, ATG3 showed high recyclability, which retains 80 % of yield even after 10 cycles. Those findings proved that ATG has high potential in the environmental remediation field. [ABSTRACT FROM AUTHOR]

The EPB shield tunnelling for mass rapid transit (MRT) Line 1 of Ho Chi Minh City (HCMC) is the first tunnel excavation in Vietnam to use a tunnel boring machine (TBM). A comprehensive instrumentation programme was developed for safety control and to obtain a better understanding of the characteristics of induced ground movement and the forecasts. The observed ground surface settlement is summarized and interpreted with respect to the tunnelling operation parameters. The settlement trough is compared with the forecast data by applying the empirical Gaussian function and numerical 2D finite‐element analysis (FEA). The trough width parameter in the city's sandy subsoil is determined. The relation between the volume loss of the ground surface and that of the tunnel (contraction ratio) is identified. The result of the investigation is useful for future shield tunnel projects in HCMC and elsewhere in Vietnam. [ABSTRACT FROM AUTHOR]

In this study, ZnO‐doped carbon aerogel is synthesized from cellulose in coconut peat with sodium alginate as a binder via both freeze‐drying and pyrolysis processes. Of those, zinc nitrate is used as not only a crosslinking agent to form gel but also a precursor source to dope ZnO in the carbon aerogel matrix. The effect of precursor ratios on the characterization and energy storage capacity of composite aerogel is investigated. As a result, it is indicated that the formed ZnO‐doped carbon aerogel possesses a highly porous structure which is typical for aerogel structure shown by SEM images, density, and porosity. Besides, via the XRD patterns, the confirmation of the ZnO crystal structure is found within the carbon aerogel lattice. In terms of energy storage, based on the specific capacitance results, the ZCA‐4 sample with a sodium alginate and cellulose weight ratio of 1:20 shows the best energy storage with a specific capacitance of 105 F/g in the voltage range of 0–0.5 V and scan‐rate speed of 0.005 V. Therewithal, the ZCA‐4 also performs high durability, high scanning speed tolerance, and stable storage performance with efficiency reaching more than 99% after 500 consecutive scan cycles. These results demonstrate that the ZnO‐doped carbon aerogel has potential applications as electrode materials in supercapacitors. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) can be considered as one of the world's indispensable chemicals. However, the synthetic process can prompt several severe environmental and human health issues. However, solar H2O2 production may provide opportunities to mitigate such issues. Graphitic carbon nitride (g‐C3N4) has emerged as one promising material for photocatalytic applications due to its unique properties. Although tremendous efforts in engineering g‐C3N4 have been proposed to improve catalytic results, the materials obtained still have some issues. Additionally, the mechanisms behind the production of H2O2 by using such materials are not yet fully understood. Herein, we conducted a literature survey reviewing the production of H2O2 using g‐C3N4‐based materials. The essential aspects of and current challenges in photocatalytic H2O2 generation are discussed, which may provide insight for researchers to overcome barriers and develop sustainable methods for H2O2 production. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles‐doped graphene oxide (AgNPs@GO) nanocomposite was green synthesized using the extract of Curcuma longa as an effective reducing and stabilizing agent.. Characterization of AgNPs and AgNPs@GO were thoroughly examined via several analysis methods. Thereby, the results show the successful formation as well as the uniform distribution of spherical nano‐sized silver fragments on the GO surface with an average size of 21.14± ${\pm }$ 3.21 nm. The materials were then tested regarding their optical sensing for H2O2 and Hg2+. In specific, AgNPs@GO indicated a great colorimetric detection towards H2O2 and Hg2+ with a remarkably low detection limit at 0.48 and 0.158 μM, respectively. Conclusively, AgNPs@GO nanocomposite poses a high potential in application sectors of the colorimetric sensor. [ABSTRACT FROM AUTHOR]

Herein, poly(propylene) (PP) was hydrophilized with oxidating agents and solvents, followed by dip‐coating with silver nanoparticles anchored GO sheets (Ag@GO) prepared by the in‐situ method as reported in our previous study to obtain silver@graphene oxide‐coated poly(propylene) (Ag@GO/PP). The impact of the modifying agents, dipping times, and coating concentrations on the antibacterial activities were studied accordingly via the inhibition zone method. The fabrics were re‐hydrophobized with the reduction of Ag@GO and the functionalization with stearic acid (SA) to form silver@reduced graphene oxide‐coated poly(propylene) (Ag@rGO/PP) and silver@graphene oxide/SA‐coated poly(propylene) (Ag@rGO‐SA/PP), respectively. Characterization of pretreated and modified PP samples was carried out by various modern analysis methods. Simultaneously, the cytotoxicity of the active layers, the release of Ag+ ions, and durability after washing were also investigated. The obtained results representing PP fabrics pretreated with HNO3/isopropanol and dipped in Ag@GO concentration of 2 g/L four times prove a sufficient approach for improving hydrophilization and bio‐compatibility for the PP samples. The fabrics greatly show an impressive interaction with precursors, mostly high antibacterial activity even after four washing cycles via appropriate releasing of Ag+ to ensure the safety in usage. They further suggest that the prepared fabrics could be utilized for actual application as a face mask. [ABSTRACT FROM AUTHOR]

In this work, a watermelon rind‐derived carbon aerogel (WRCA) was synthesized via a facile and green procedure including hydrothermal combined freeze‐drying and pyrolysis technique. The influences of pyrolysis conditions on the characteristics, adsorption capacity, and energy storage of the produced WRCA were thoroughly investigated under two distinctive pyrolysis conditions in N2 and CO2 media to obtain the corresponding WRCA‐N and WRCA‐C products, respectively, at different temperatures (600, 700, and 800 °C). As a result, WRCA‐N samples exhibited notable hydrophobicity with a wetting angle of 127°, showing excellent concordance with the adsorbent field. Furthermore, the maximum adsorption capacity of used coconut oil, hexane, butanol, and chloroform for WRCA‐N pyrolyzed at 800 °C (WRCA‐N800) reached 70.521, 53.506, 58.102, and 59.913 g/g, respectively, whilst the adsorption process also followed the pseudo‐first‐order kinetic model. On the other hand, WRCA‐C held up considerable hydrophilic traits and cannot be used to adsorb organic matters. Nonetheless, WRCA‐C activated at 600 °C (WRCA‐C600) indicated the best physicochemical properties and energy storage capacity with better specific capacitance (190 F/g) compared to WRCA‐N600 (31.40 F/g), thanks to its large specific surface area, high porosity (91.27 %), and higher hetero‐element O content (9.79%) than other samples. Additionally, the electrochemical characteristics of WRCA‐C600 electrode were alternatively confirmed using the 2‐electrode supercapacitor model, demonstrating a high energy density (26.38 Wh/kg) and power density (2374.50 W/kg). The obtained results demonstrate the promising applications of carbon aerogel synthesized from the watermelon rind in the adsorption and energy storage sectors. [ABSTRACT FROM AUTHOR]

Since the recent successful experimental synthesis of MoSi2N4 [Science, 369 (2020), 670], the "MA2Z4 family" has been of particular interest to the scientists in the field of materials science due to its outstanding physical properties. In this paper, the first‐principles calculations are performed to study the structural, elastic, and electronic properties of novel two‐dimensional (2D) Janus MSiGeN4 monolayers (M = Ti, Zr, Hf). The calculations of phonon spectra indicate that monolayers MSiGeN4 are dynamically stable and can be experimentally synthesized. The obtained Young's modulus and Poisson's ratio of the Janus structures MSiGeN4 are much larger than that of other binary 2D materials and meet the mechanical stability criteria suggested by Born and Huang. In the calculations using either PBE or HSE06 functionals, the Janus MSiGeN4 structures exhibit indirect semiconductor characteristics with larger band gaps than that of similar septuple‐atomic‐layer materials, such as MoSiGeN4 and WSiGeN4. In addition, the influences of biaxial strain and external electric field on the electronic structure of MSiGeN4 are investigated. It is found that the biaxial strain tunes the electronic characteristics more significantly than the external electric field. The obtained results can provide insights into novel Janus monolayers with potential applications in electronic devices. [ABSTRACT FROM AUTHOR]

In this study, graphene oxide (GO) was prepared from graphite by improved Hummers' method. Graphene oxide aerogel (GOA) was synthesized via the ice segregation induced self‐assembly method. Various modern analytical methods were utilized to characterize GOA. The results revealed the aerogel structure with a pore size of 100–150 μm, a specific surface area of 515.21 m2/g, and a pore volume of 2.08–2.16 cm3/g. The synthesized GOA was applied as an adsorbent for the removal of phenol (PN) and bisphenol A (BPA) with a maximum adsorption capacity of 117.65 and 70.17 mg/g, respectively. Response surface methodology involving a rotating central composite design was applied to investigate simultaneously the effects of adsorption variables including adsorption time, pH, and initial concentration on the removal efficiency of GOA for PN or BPA. The results showed that the optimal adsorption efficiency for PN was 92.15 % with an adsorption time of 208.52 min, a pH of 6.08, and an initial PN concentration of 30 mg/L. Regarding BPA, the optimal adsorption efficiency was 95.27 % with an adsorption time of 352.79 min, a pH of 4.91, and an initial BPA concentration of 20 mg/L. The adsorption of both PN and BPA onto GOA was appropriate with the Langmuir model, in which the maximum adsorption capacity of GOA for PN and BPA was 117.65 and 70.175 mg/g, respectively. The results confirmed that the adsorption of PN and BPA onto GOA was monolayer adsorption on a homogeneous surface. The adsorption mechanism of GOA for PN or BPA depended mainly on the electrostatic interaction and hydrogen bonding between −OH of PN, BPA, and oxygen‐containing functional groups of GOA. Besides, π‐π interaction between carbon rings of GOA and PN or BPA also contributed to the enhancement of adsorption performance. The results showed that GOA exhibited potential application in the treatment of organic pollutants. Besides, the evaluation of the morphology of the GOA and the simultaneous effects of different factors can contribute to the advancement of graphene‐based materials and the improvement of wastewater treatment. [ABSTRACT FROM AUTHOR]

In this study, polydimethylsiloxane/tetraethyl‐orthosilicate (PDMS/TEOS) hybrid materials with different TEOS ratios were synthesized by cross‐linking method. Ceramic tube‐supported PDMS/TEOS membranes were fabricated by dip‐coating method. Effect of TEOS content, feed concentration, and feed temperature through separation of a furfural–water mixture by pervaporation (PV) technology was investigated. The highest PV performance was obtained with the total flux of 1.19 kg/m2h with TEOS content of 1.8 g, furfural feed concentration of 30 wt.%, operating temperature, and vacuum pressure at 100 kPa and 50 °C, respectively. PDMS/TEOS was successfully synthesized and coated on ceramic tube‐supported with a thickness of 15 μm. The ceramic tube‐supported membrane demonstrated good hydrophobicity with a contact angle of 109.5° and excellent thermal stability at 450 °C. The obtained results demonstrated that the ceramic tube‐supported PDMS/TEOS membrane is potent to be utilized for the separation of the furfural‐water mixture by PV technology. [ABSTRACT FROM AUTHOR]

Developmental and epileptic encephalopathies (DEE) refers to a group of rare and severe neurodevelopmental disorders where genetic etiologies can play a major role. This study aimed to elucidate the genetic etiologies of a cohort of 53 Vietnamese patients with DEE. All patients were classified into known electroclinical syndromes where possible. Exome sequencing (ES) followed by a targeted analysis on 294 DEE‐related genes was then performed. Patients with identified causative variants were followed for 6 months to determine the impact of genetic testing on their treatment. The diagnostic yield was 38.0% (20/53), which was significantly higher in the earlier onset group (<12 months) than in the later onset group (≥12 months). The 19 identified variants belonged to 11 genes with various cellular functions. Genes encoding ion channels especially sodium voltage‐gated channel were the most frequently involved. Most variants were missense variants and located in key protein functional domains. Four variants were novel and four had been reported previously but in different phenotypes. Within 6 months of further follow‐up, treatment changes were applied for six patients based on the identified disease‐causing variants, with five patients showing a positive impact. This is the first study in Vietnam to analyze the genetics of DEE. This study confirms the strong involvement of genetic etiologies in DEE, especially early onset DEE. The study also contributes to clarify the genotype–phenotype correlations of DEE and highlights the efficacy of targeted ES in the diagnosis and treatment of DEE. [ABSTRACT FROM AUTHOR]

The ultrasound‐assisted enzymatic extraction (UAEE) in this work was utilized to extract triterpenoid from Ganoderma lucidum (G. lucidum). The enzyme concentration (%), ethanol: material ratio (ml/g), ultrasonic duration (min), ultrasonic temperature (°C), and ultrasonic power (W) were all studied as factors impacting triterpenoid content. The experiment was developed using the Plackett–Burman model to filter out the influencing factors and choose the component that has the greatest impact on the triterpenoid content in order to improve the extraction conditions using the Box–Benhken model. The result showed that the highest triterpenoid content of 11.65 mg/g could be obtained under extraction conditions including enzyme concentration of 2.5%, ethanol:material ratio of 20:1 ml/g, and ultrasonic power of 480 W. The results of gas chromatography–mass spectrometry and Fourier‐transform infrared spectrometry analysis showed the presence of more phytochemicals in the extract obtained using UAEE compared with the maceration method. Scanning electron microscopy images were used to confirm the assistance of enzymes and ultrasound waves to disrupt the cell walls of G. lucidum. The antibacterial property of the extract by UAEE was evaluated against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella enterica and able to suppress the development of hepatocellular carcinoma, breast carcinoma, and epidermic carcinoma. Practical applications: The main objective of this paper is to improve extraction efficiency of triterpenoid from Ganoderma lucidum with the combination of enzymatic‐assisted extraction and ultrasound‐assisted extraction. Even though many researchers were worked on different extraction techniques, very few researchers were reported the factor‐screening experiment using Plackett–Burman model and optimization of this extraction system using Box–Behnken model. The anticancer activity of the extract is the main criteria for evaluating the quality of this product. The results found that enzyme concentration, ethanol: material ratio, and ultrasonic power had a significant impact on triterpenoid content, and the extract under optimum conditions exhibited potential medium anticancer capacity using MTT assay. This result is especially useful in applying G. lucidum extract in various fields including health promotion, functional food, and cancer therapy. [ABSTRACT FROM AUTHOR]

In this work, the supercritical CO2 extraction methodology was utilized to extract triterpenoids from Ganoderma lucidum (G. lucidum). Box‐Behnken experimental design was employed in order to optimize the extraction conditions. Results showed that the highest triterpenoid content of 4.122±0.09 mg/g could be obtained under extraction conditions including pressure of 312 bar, temperature of 53 °C, solvent‐to‐sample ratio 1.74 mL/g, and time of 120 min. The extract was analyzed using Fourier transform infrared spectrometry, gas chromatography‐mass spectrometry, and scanning electron microscopy to confirm the support of the supercritical CO2 in disrupting the cell walls of G. lucidum. The 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging was carried out for the antioxidant evaluation. The antibacterial properties of the extract were evaluated against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica with inhibition zone of 21.33, 21.67, 23.67, and 14.00 mm, respectively. Furthermore, the extract was able to suppress the development of hepatocellular carcinoma, breast carcinoma, and epidermic carcinoma the half‐maximal inhibitory concentration values of 50.32, 75.34, and 113.16 μg/mL, respectively. Therefore, the present investigation demonstrates the potential use of G. lucidum, which is high in triterpenoid in the manufacture of functional foods, health promotion, against bacterial infections, and cancer therapy. [ABSTRACT FROM AUTHOR]

Background: Inflammatory skin diseases were the most common problem in dermatology. This study aimed to develop a circuit by using a simple method for noninvasive, objective, and real‐time skin inflammation screening. Materials and methods: Sprague‐Dawley rats were used in this study. The rats were chemically induced to suffer from skin inflammation at the back of their left‐hand side while the right‐hand side of their back remained untreated serving as a control. Impedance (Z) spectrum of the rat's skin was recorded. Results: Two characteristic frequencies (4.5 and 48.3 kHz) were found. At the two frequencies, the impedance of inflammatory skin tissue (ZIST) was found to be significantly (P <.05) smaller than that of normal healthy skin tissue (ZNHST). Moreover, the ratio of the impedance measured at 4.5 kHz (Zf = 4.5 kHz) to the impedance measured at 48.3 kHz (Zf = 48.3 kHz), that is, Zf = 4.5 kHz/Zf = 48.3 kHz, was capable of skin inflammation screening. It was observed that the inflammatory skin tissue (IST) had the smaller value of Zf = 4.5 kHz/Zf = 48.3 kHz (value < 8.5) and normal healthy skin tissue (NHST) had the higher value of Zf = 4.5 kHz/Zf = 48.3 kHz (value ≈ 10) which almost remained constant. Conclusion: A circuit was developed which was used for measuring the skin impedance accurately at the two characteristic frequencies for skin inflammation screening. [ABSTRACT FROM AUTHOR]

We have reported the electronic, magnetic and optical properties of carbon doped bilayer hexagonal boron nitride (h‐BN) using thedensity functional theory. A single C‐doping at B/N sites gives the large band gap similar to dilute magnetic semiconducting behaviour with a finite net magnetic moment of 1.001 and 0.998μB, respectively. For double doping at B/N sites the net magnetic moment increases to 1.998 and 1.824μB, respectively. Upon C‐doping at N‐site, we obtained transition from non‐magnetic semiconductor (pristine) → magnetic semiconductor (1C) → half‐metal ferromagnetic (2C) → metal (3C). In case of the B site, we observed metallic behaviour for 2C‐doping. As 1,2 C‐doping at the B site reduces the energy band gap from 1.8 eV to 0.81 eV, falls in the visible range and offers an opportunity to utilized as a photocatalyst material. C‐doped systems show a magnetic semiconducting behavior crucial for spintronic applications. [ABSTRACT FROM AUTHOR]

Background. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic of pneumonia spreading around the world, leading to serious threats to public health and attracting enormous attention. There is an urgent need for sensitive diagnostic testing implementation to control and manage SARS-CoV-2 in public health laboratories. The quantitative reverse transcription PCR (RT-qPCR) assay is the gold standard method, but the sensitivity and specificity of SARS-CoV-2 testing are dependent on a number of factors. Methods. We synthesized RNA based on the genes published to estimate the concentration of inactivated virus samples in a biosafety level 3 laboratory. The limit of detection (LOD), linearity, accuracy, and precision were evaluated according to the bioanalytical method validation guidelines. Results. We found that the LOD reached around 3 copies/reaction. Furthermore, intra-assay precision, accuracy, and linearity met the accepted criterion with an RSD for copies of less than 25%, and linear regression met the accepted R 2 of 0.98. Conclusions. We suggest that synthesized RNA based on the database of the NCBI gene bank for estimating the concentration of inactivated virus samples provides a potential opportunity for reliable testing to diagnose coronavirus disease 2019 (COVID-19) as well as limit the spread of the disease. This method may be relatively quick and inexpensive, and it may be useful for developing countries during the pandemic era. In the long term, it is also applicable for evaluation, verification, validation, and external quality assessment. [ABSTRACT FROM AUTHOR]

β‐MoO3, the molybdenum oxide phase with the highest catalytic activity, is a promising material in optical, chemical, and electronics applications as a replacement for α‐MoO3. α‐MoO3 1D nanostructures such as whiskers and fibers have been investigated and used in applications. However, difficulties in the synthesis of one‐dimensional β‐MoO3 have obstructed researchers in the study of its properties. In this research, β‐MoO3 nanowhiskers were synthesized from core/shell molybdenum/molybdenum oxide wires by pulsed wire discharge in mixed oxygen and argon gases. X‐ray diffraction analysis identified the main phase in the obtained samples as β‐MoO3. Electron microscopy observations revealed whiskers with an average length and width of 216 nm and 23 nm, respectively. Transmission electron microscopy lattice imaging confirmed the successful synthesis of β‐MoO3 nanowhiskers. Various models were considered to explain the formation of β‐MoO3 nanowhiskers, including mechanical fragmentation of α‐MoO3 layers as well as vapor‐liquid‐solid and vapor‐solid mechanisms. The phase transformation from α to β‐MoO3 under a nucleation process was explained based on the Mo‐O phase diagram. To the best of our knowledge, this is the first report of β‐MoO3 nanowhisker synthesis. [ABSTRACT FROM AUTHOR]

In this study, to investigate the extraction of triterpenoids from the Vietnamese red G. lucidum by ultrasound‐assisted extraction (UAE) method using ethanol as a solvent, the determination of the four single factors influence on the triterpenoid content including liquid‐to‐solid ratio, extraction power, extraction temperature, and extraction time was carried out for the performance of experiments on simultaneous effects by Central Composite design. The results showed that based on ultraviolet‐visible spectroscopy analysis, the highest yield of triterpenoids could be achieved with value of 18.3751 mg/g under optimal extraction conditions including extraction time of 60 min, ultrasonic power of 360 W, liquid‐to‐solid ratio of 38 : 1 mL/g, and ultrasonic temperature of 48 °C. To determine the characteristics of the obtained extract, the Gas chromatography‐mass spectrometry, the Fourier‐transform infrared spectroscopy, scanning electron microscope, and the thermogravimetric analyzer were employed in this study. Besides, for antioxidant capacity evaluation, the DPPH free radical scavenging assay, H2O2 scavenging assay, and the ABTS radical cation decolorization assay were carried out whereas the anticancer evaluation results denoted the potential for anticancer agents of G. lucidum extract. Therefore, it could be concluded that UAE is a promising method for triterpenoid extraction with antioxidant properties. [ABSTRACT FROM AUTHOR]

Traditional methods of measuring a joint angle are neither repeatable nor accurate and cannot instantly display, record, and upload the data onto a cloud drive. These mechanisms require development if they are to be used to evaluate rehabilitation programs. This pilot study aim is to create a simple dynamic joint angle measurement system and develop a hand rehabilitation application for stroke users using small and sensitive 3-axis accelerometers. Using Bluetooth communication technology, an electrogoniometer is developed to measure the free range of motion of lower limb joints and automatically send and save all data on to a cloud drive. The reliability of the proposed device is evaluated by comparison with a commercial electrogoniometer. Five healthy youth subjects and five health elderly subjects are involved in the evaluation process for this pilot study. The accuracy and repeatability of the proposed device are tested using Bland–Altman plots and linear correlation analysis. Measurements that were made by the proposed device and a commercial electrogoniometer are shown to be comparable and repeatable, as confirmed by Bland–Atman plots. There is also a very high degree of linear correlation (R2 > 0.99 for all joint angle measurements) between the lower limb joint angles that are measured using both devices. In conclusion, a portable, highly accurate and repeatable device was designed to be used for clinical assessment and for rehabilitation application that gives increased motivation to the user. [ABSTRACT FROM AUTHOR]

In this study, the employment of aqueous enzymolysis using alcalase with ethanolic ultrasonication extraction method was investigated. The cordycepin content was analyzed by using reversed‐phase high‐performance liquid chromatography with a diode array detector. The result showed that the highest cordycepin content of 0.4365±0.0309 mg/g could be obtained under extraction conditions including total enzyme volume of 240 μL, incubation time of 50 min, incubation temperature of 55 °C, and ultrasonic power of 840 W. The comparative studies of antioxidant activities of the extract were determined in terms of the DPPH free radical scavenging assay, ferric ion reducing power assay, and H2O2 scavenging assay. Additionally, the MTT assay was conducted to evaluate the anticancer activities of the extract, illustrating the cytotoxic property against Hep‐G2 cancer cells with the half‐maximal inhibitory concentration (IC50) value of 12.20±0.03 μg/mL compared to that of 0.36±0.03 μg/mL for ellipticine, MCF‐7 cancer cells with the IC50 value of 11.60±0.09 μg/mL compared to that of 0.51±0.04 μg/mL for ellipticine, and Lu cancer cells with the IC50 value of 34.50±0.25 μg/mL compared to that of 0.32±0.03 μg/mL for ellipticine. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya Linn.) is popularly cultivated in most tropical countries such as Malaysia, Vietnam, the West Indies, and throughout Africa. In the present work, an ultrasound‐assisted extraction (UAE) method has been developed for flavonoid extraction from Vietnamese male Carica papaya (C. papaya) flowers. Various influential operating parameters such as extraction time, ultrasonic power, solvent–to–material ratio, and extraction temperature on the flavonoid content were examined to optimize the extraction process. The result showed that under optimum extraction conditions including extraction time of 33 min, ultrasonic power of 240 W, solvent–to–material ratio of 27 : 1 mL/g, and extraction temperature of 46∘C , the flavonoid content obtained was of 10.648±0.228 mg QE/g, which was found to be higher than that obtained by hot water extraction, enzyme‐assisted extraction, and ultrasound‐assisted enzymatic extraction methods. Therefore, UAE could be considered as the most efficient extraction method for flavonoids from Vietnamese male C. papaya flowers. In addition, the extract obtained under optimum conditions was tested bioactivities to prove the medicinal uses of flavonoids extracted from Vietnamese male C. papaya flowers with the half‐maximal inhibitory concentration values for antioxidant effect and anticancer effect against Hep‐G2 cell lines at 179.69± 0.03 and 56.63± 1.25 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Background. There is a shortage of chemical reagents for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis and a surge of SARS-CoV-2 cases, especially in limited-resource settings. Therefore, the combination of an optimal assay kit is necessary. Methods. We compared the ability to screen SARS-CoV-2 among three primer-probe sets in two different master mixes, Invitrogen™ SuperScript™ III One-Step RT-PCR and LightCycler Multiplex RNA Virus Master. Results. The assay with TIB-Molbiol, IDT, and Phu Sa sets for LightCycler Multiplex RNA Virus Master or Invitrogen™ SuperScript™ III One-Step RT-PCR showed positive results from a single reaction of triplicate in the three days of 4.8 copies per reaction. R squared and amplification efficiency were 0.97 and ranged from 107 to 108%, respectively. Conclusions. Our findings indicated that TIB-Molbiol, IDT, and Phu Sa primer-probe sets could be beneficial for the laboratory screening of SARS-CoV-2 by RT-qPCR assay of E gene. There is a need to consider the combination of these reagent sets as a new strategy to increase the testing capacity of screening programs for COVID-19. [ABSTRACT FROM AUTHOR]

This paper carries out an experimental study to enhance the quality of the characteristic transmittance curve in the infrared range of 2.5–7 µm of the optical magnesium fluoride (MgF2) ceramic. This work evaluates the effectiveness of using vacuum environment in the MgF2 ceramic hot-pressing technique by comparing the density and the quality of the transmittance characteristic curve of two types of specimens manufactured by the hot-pressing technique corresponding to open air and vacuum environment under the same technological parameters including temperature 650°C, time 30 min, and pressure 200 MPa. The results present that, in comparison with using the hot-pressing technique in the open air, when using the hot-pressing technique in a vacuum environment, the transmittance increases about 4–10%, the characteristic transmittance curve is smoother and has fewer peak points, and the wide of peak points are smaller. When hot-pressing in a vacuum environment, the temperature can be up to 750°C in order to obtain the magnesium fluoride (MgF2) ceramic with the highest quality of characteristic line in the infrared range of 2.5–7 µm. Seventeen specimens are manufactured to conduct the experimental study in order to figure out the optimal set of technological parameters (temperature T = 640.9°C, time t = 33.0 min, and pressure P = 231.4 MPa) when hot-pressing in a vacuum environment by the experimental planning approach. [ABSTRACT FROM AUTHOR]

In this study, we investigated the improvement of the thermal and mechanical properties of Vietnam deproteinized natural rubber (DPNR) via graft copolymerization of methyl methacrylate (MMA). The graft copolymerization was achieved successfully in latex stage using tert-butyl hydroperoxide (TBHPO) and tetra-ethylenepentamine (TEPA) as radical initiators at 30°C. By grafting with various MMA feeds and initiator concentration of 6.6 × 10 − 5 mol/g-rubber, the highest grafting efficiency and conversion were achieved at MMA of 15 wt.% per kg of rubber, 68% and 90%, respectively. The structure of grafted copolymers was characterized by 1H NMR, FTIR-ATR, and GPC, and thermal properties were investigated through DSC and TGA measurements. These showed that graft copolymers were more stable and rigid than DPNR. Storage modulus (G ′ ) of graft copolymer was found to double that of DPNR, which contributed to the formation of graft copolymer. After sulfur vulcanization, the mechanical properties of DPNR-graft-PMMA, such as tensile strength, tear strength, and hardness, were improved significantly. Curing behaviors of the graft copolymers were found to be remarkably better than virgin DPNR. [ABSTRACT FROM AUTHOR]

The controlled synthesis of few‐layer vertically oriented MoS2 flakes for high‐performance NO2 gas sensor applications is introduced. The density and the thickness of MoS2 nanosheets are controlled by varying the heating rate of the chemical vapor deposition process. Herein, it is confirmed that the nanoflakes of about three layers are obtained under the heating rate of 5 °C using powders of MoO3 and S as precursors without using any catalyst. This is very advantageous because no catalyst is used, there is no need of buffer layer at the bottom of the MoS2 thin‐film flacks, thus omitting the leakage current when measuring the electrical signal and enhancing the gas sensing performance. Gas sensing measurements demonstrate that the interconnected vertically oriented MoS2 nanoflakes have a good response value of 20.1% to 0.5 ppm NO2 at room‐temperature (RT), and 1.73% at 150 °C. The sensor shows full recovery characteristic at a measured temperature of 150 °C with response and recovery time of about 15 and 100 s, respectively. The sensor also exhibits good selectivity with the ignorable response to SO2, H2, NH3, H2S, and a low detection limit of 42 ppb. [ABSTRACT FROM AUTHOR]

In this study, fucoidan was extracted from the Vietnamese brown seaweed Sargassum mcclurei by ultrasound – assisted extraction method (UAE) using ethanol as a solvent. The effects of single factors on total polysaccharide (TPS) content were then investigated, followed by the screening of main factors affecting TPS content based on their effect sizes and p‐values in analysis of variance. The response surface methodology using the Box‐Behnken design was applied to investigate simultaneous effects of four main factors including solvent‐to‐material ratio, extraction time, ultrasonic power, and extraction temperature. The optimal conditions for fucoidan extraction were identified with solvent‐to‐material ratio of 24 : 1 mL/g, extraction time of 49 min, ultrasonic power of 360 W, and extraction temperature of 54∘C. The highest yield of TPS obtained under these conditions was 7.1203 mg/g. Besides, extraction of fucoidan using hot water method was also carried out to compare with UAE method in terms of TPS content. The bioactivity tests showed the extract had the anti‐oxidation activity with the half‐maximal inhibitory concentration (IC50) value of 0.4261 ± 0.0008 mg/mL, cytotoxic effect on breast carcinoma cells and human lung carcinoma with IC50 values of 95.80 ± 4.75 and 129.00 ± 0.66 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Pulsed wire discharge was used to prepare nanoparticles of molybdenum and its carbides from Mo wires in a gas mixture of argon and kerosene at pressures of 100, 50, and 25 kPa. The different pressures affected the carburization process and particle formation. The most effective pressure was 25 kPa, where the volume fraction of MoC was identified by Rietveld refinement of X‐ray diffraction data to be 98.4%. The particle size distribution was also obtained from transmission electron microscopy measurements, and the smallest geometric mean diameter was determined tobe 24.3 nm for the sample prepared at 25 kPa. [ABSTRACT FROM AUTHOR]

Triterpenoid saponins were extracted from of Pseuderanthemum palatiferum (Nees) Radlk. dry leaf powder by using enzyme‐assisted extraction method. Effects of single factors on total saponins content (TSC) were investigated. Then, a full factorial design with two levels was conducted to screen the main factors affecting TSC. Two main factors as extraction temperature and time were determined. Response Surface Methodology with central composite design was used to study simultaneous effects of these factors on TSC. Results showed that the optimum conditions were 54.9 °C and 80.8 min. The extract under these conditions was tested with bioactivities. The extract had the haemolytic index of 256.74 mL, anti‐inflammatory activity with IC20 of 0.56 μg/mL, anti‐oxidation activity with IC50 values of DPPH, ABTS, and hydroxyl of 61.47, 1.42, and 30.33 μg/mL, respectively, and cytotoxicity on cancer cell line HepG2. Accordingly, triterpenoid saponins from Pseuderanthemum palatiferum (Nees) Radlk. could be considered as a valuable constituent. [ABSTRACT FROM AUTHOR]