Search

Among other fields, climate change has a great influence on metal corrosion that reduces the durability and reliability of steel structures. A time-dependent reliability analysis includes time-dependent climate scenarios and deterioration processes as well as random variables, material properties, and dimensions. The extent of corrosion damage is calculated by tracking the evolution of the corrosion process using Monte Carlo simulations. The current paper presents a time-dependent reliability assessment of a continuous I-shaped steel beam, considering the corrosion effects of climate change in Vietnam. The results showed that the safety probability of a continuous steel beam considering metal corrosion from the pristine to 100 years reduces from 96.77% to 63.08%. These findings can be used to assess and provide a cost-technical analysis of climate adaptation measures.

The effects of surface-active nanoparticles and surfactants on the behavior of oil-water interfaces have implications for a variety of industrial processes related to multiphase flows including separation processes, enhanced oil recovery, and environmental remediation. In this work, the migration of an oil droplet in shear flow is investigated with the presence of surface-active molecules and nanoparticles at the oil-water interface. Pure oil (heptadecane) in water and oil with the presence of Janus nanoparticles (JPs) and/or octaethylene glycol monododecyl ether, a nonionic surfactant, were examined using coarse-grained computations. The shear flow field was created utilizing a Couette flow, where the top wall of a channel moved with a specified velocity and the bottom wall was kept stationary. The dissipative particle dynamics (DPD) method was applied. The oil drop was placed on the stationary wall, and its displacement was recorded over time. When surfactants were added at the oil-water interface, the slip of the water over the oil drop was reduced, leading to a larger displacement of the drop. Moreover, surfactant molecules tended to concentrate toward the rear side of the oil drop rather than the front as the drop moved in the flow field. The presence of only JPs on the oil-water interface resulted in slower droplet migration. In the presence of both JPs and surfactants, the effect of JPs on the oil-surfactant-water system was investigated by changing the number of JPs on the drop surface while keeping the concentration of the surfactant constant. Under the same shear rate, the droplet's migration speed increased in the presence of both surfactants and JPs compared to the case of bare oil. The JPs appeared to follow a repeated pattern of motion while residing close to the solid substrate-oil drop contact line. These findings elucidate the contribution of both surfactants and JPs on oil drop displacement for enhanced oil recovery or remediation of an oil-contaminated subsurface.

The article discusses the features of Al–Mg–Sc aluminum alloy radial shear rolling (RSR). The RSR process was modeled by the finite element method in the QForm 3D program with the variable elongation ratio per pass and rolling speed. The results obtained were used as a basis for studying the temperature field of the rod in the deformation zone taking into account the cyclic nature of deformation and the configuration of flow paths. It was found that the temperature field in the deformation zone is determined by significant differences in the metal flow path geometry in surface layers and in the axial zone. When the elongation ratio is varied from 1.6 to 2.4, heating occurs inconsistently from the center to the surface. The highest temperature rise occurs for an area that is located ~0.3R from the surface. For the axial zone, temperature variation in the deformation zone occurs smoothly and with an insignificant temperature difference of 5–10 °C. Highest temperature fluctuations are observed on the rod surface, and this is explained by deformation heating and simultaneous contact with a cold roll during each deformation cycle. As the rolling speed decreases, a picture of the rod temperature field distribution in the deformation zone is observed with the temperature in central layers exceeding the surface temperature. Due to the long time of the rod contact with the roll, the surface temperature fluctuates up to 40–50 °C at each deformation cycle. As the rolling speed rises, the amplitude of temperature fluctuations on the surface decreases, and deformation heating increases. The data obtained on the relationship between control process parameters and rod temperature field variation can be useful in the design of rolling process modes.

This study examined the discretization random field of the elastic modulus by a point method to develop a stochastic finite element method for the stochastic buckling of a non-uniform column. The formulation of stochastic analysis of a non-uniform column was constructed using the perturbation method in conjunction with the finite element method. The spectral representation was used to generate a random field to employ the Monte Carlo simulation for validation with a stochastic finite element approach. The results of the stochastic buckling problem of non-uniform columns with the random field of elastic modulus by comparing the first-order perturbation technique were in good agreement with those obtained from the Monte Carlo simulation. The numerical results showed that the response of the coefficient of variation of critical loads increased when the ratio of the correlation distance of the random field increased.

1. The objective of this study was to examine the influence of dietary soluble non-starch polysaccharide (sNSP) level and xylanase supplementation on productive performance, viscosity and pH along the gastrointestinal tract in laying hens. Excreta moisture content, ileal and caecal microbiota and short-chain fatty acid (SCFA) composition and apparent total tract nutrient utilisation were measured.2. Hyline Brown laying hens (n = 144) were housed individually at 25 weeks of age and allocated to one of the four wheat-based dietary treatments in a 2 × 2 factorial arrangement, consisting of two levels of sNSP (High 13.40 g/kg or Low 11.22 g/kg), with or without xylanase (0 or 12,000 BXU/kg). Birds were fed the dietary treatments for 56 d.3. Increasing dietary sNSP increased jejunum viscosity, degradability of total NSP, total tract flow of insoluble arabinose, and succinic acid concentration in the caeca (P 0.05). Feeding high sNSP decreased excreta moisture content, total tract energy retention and free oligosaccharide, total tract flow of soluble and insoluble galactose and insoluble rhamnose and fucose, and ileal acetic and lactic acid concentrations (P 0.05), and tended to reduce egg production (P = 0.058).4. Supplementation with xylanase resulted in reduced jejunum and ileum viscosity, caecal pH, excreta moisture, flow of soluble arabinose and glucose and insoluble arabinose and xylose, caecal concentration of

This research report outlines the Transforming Disability Knowledge, Research, and Activism project (TDKRA) and concludes with a set of recommendations. TDKRA was a collaborative research and activism project funded by the Social Sciences and Humanities Research Council (SSHRC) between 2016-2020. The project aimed to address the gap in knowledge about the situation of women and girls with disabilities in three disadvantaged communities in Vietnam and to build potential for their activism. The main objective of the project was to engage girls and women with disabilities in knowledge production as a form of activism for their inclusion. It also aimed to connect research and activism to build a more transformative approach to inclusion and social justice in the global South.

Interference with protein-protein interfaces represents an attractive as well as challenging option for therapeutic intervention and drug design. The enzyme tRNA-guanine transglycosylase, a target to fight Shigellosis, is only functional as a homodimer. Although we previously produced monomeric variants by site-directed mutagenesis, we only crystallized the functional dimer, simply because upon crystallization the local protein concentration increases and favors formation of the dimer interface, which represents an optimal and highly stable packing of the protein in the solid state. Unfortunately, this prevents access to structural information about the interface geometry in its monomeric state and complicates the development of modulators that can interfere with and prevent dimer formation. Here, we report on a cysteine-containing protein variant in which, under oxidizing conditions, a disulfide linkage is formed. This reinforces a novel packing geometry of the enzyme. In this captured quasi-monomeric state, the monomer units arrange in a completely different way and, thus, expose a loop-helix motif, originally embedded into the old interface, now to the surface. The motif adopts a geometry incompatible with the original dimer formation. Via the soaking of fragments into the crystals, we identified several hits accommodating a cryptic binding site next to the loop-helix motif and modulated its structural features. Our study demonstrates the druggability of the interface by breaking up the homodimeric protein using an introduced disulfide cross-link. By rational concepts, we increased the potency of these fragments to a level where we confirmed their binding by NMR to a nondisulfide-linked TGT variant. The idea of intermediately introducing a disulfide linkage may serve as a general concept of how to transform a homodimer interface into a quasi-monomeric state and give access to essential structural and design information.

Aim: The study was conducted to determine the prevalence and characterization of the Pasteurella multocida isolates from suspected pigs in Vietnam. Materials and Methods: A total of 83 P. multocida strains were isolated from lung samples and nasal swabs collected from pigs associated with pneumonia, progressive atrophic rhinitis, or reproductive and respiratory symptoms. Isolates were subjected to multiplex polymerase chain reaction (PCR) for capsular typing, detection of virulence-associated genes and antibiotic resistance genes by PCR. The antimicrobial sensitivity profiles of the isolates were tested by disk diffusion method. Results: All the isolates 83/83 (100%) were identified as P. multocida by PCR: serogroup A was obtained from 40/83 (48.19%), serogroup D was detected from 24/83 strains (28.91%), and serogroup B was found in 19/83 (22.35%) isolates. The presence of 14 virulence genes was reported including adhesins group (ptfA – 93.97%, pfhA – 93.97%, and fimA – 90.36%), iron acquisition (exbB – 100%, and exbD – 85.54%), hyaluronidase (pmHAS – 84.33%), and protectins (ompA – 56.62%, ompH 68.67%, and oma87 – 100%). The dermonecrotoxin toxA had low prevalence (19.28%). The antimicrobial susceptibility testing revealed that cephalexin, cefotaxime, ceftriaxone, ofloxacin, pefloxacin, ciprofloxacin, and enrofloxacin were the drugs most likely active against P. multocida while amoxicillin and tetracycline were inactive. The usage of PCR revealed that 63/83 isolates were carrying at least one of the drug resistance genes. Conclusion: Unlike other parts of the word, serotype B was prevalent among Vietnamese porcine P. multocida strains. The high antibiotic resistance detected among these isolates gives us an alert about the current state of imprudent antibiotic usage in controlling the pathogenic bacteria.

Zusammenfassung Hintergrund Fremdbluttransfusionen sind bei vielen onkologischen Eingriffen durch die Anwendung der maschinellen Autotransfusion (MAT) vermeidbar. Es ist fraglich, ob mit dem Einsatz von Leukozytendepletionsfiltern (LDF) eine ähnliche Sicherheit wie bei der Bestrahlung des autologen Blutprodukts hinsichtlich der Vermeidung von Rezidiven erreicht sowie damit eine einfachere und flächendeckendere Versorgung werden kann. Ziele der vorliegenden Übersichtsarbeit waren die Neubeurteilung der vorausgegangenen Metaanalyse aus dem Jahr 2012 aufgrund der seitdem aktualisierten Datenlage und die Ermittlung der Sicherheit von LDF zur Elimination von Tumorzellen. Material und Methode In dem systematischen Review wurden alle Studienpublikationen integriert, die über die gängigen Online-Bibliotheken zugängig sind sowie die Rezidivrate, Letalität, den Transfusionsbedarf und die Krankenhausverweildauer nach dem Einsatz von MAT ohne Bestrahlung mit oder ohne LDF zum Inhalt haben. Die Evidenz wurde mithilfe der „Grades-of-recommendations“(GRADE)-Methodik beurteilt. Ergebnisse Es fanden sich 7 neue Observationsstudien und insgesamt 7 Metaanalysen aus Teilbereichen der Onkochirurgie. Die Evidenz ist gering. Insgesamt wurden 27 Observations- und Kohortenstudien in eine Metaanalyse eingeschlossen. Bei der Versorgung von Patienten mit unfiltriertem oder leukozytendepletiertem Eigenblut war die Rezidivrate verringert („odds ratio“ [OR] 0,71, 95 %-Konfidenzintervall [95 %-KI] 0,58–0,86) im Vergleich zu nichttransfundierten Patienten sowie mit Fremdblut oder gelagertem Eigenblut versorgten Patienten. Letalität und Krankenhausverweildauer sind gegenüber der Versorgung mit Fremdblut- und der Eigenblutspende unverändert. Die Transfusionsrate ist wegen eines erheblichen Selektionsbias und großer Heterogenität nicht beurteilbar. Zur LDF fanden sich 14 Studien (davon 5 In-vitro-Studien). Die Sicherheit der Leukozytendepletion ist durch die Elimination von Tumorzellen im Bereich von 99,6–99,9 % gegeben. Schlussfolgerung Randomisierte Studien zum Vergleich von MAT und Fremdbluttransfusion als auch von LDF und Bestrahlung sind wünschenswert, aber nicht verfügbar. Im Vergleich zu homolog oder nichttransfundierten Patienten existiert keine Evidenz für eine erhöhte Tumorrezidivrate oder ein schlechteres Outcome der Patienten, bei denen MAT während der Tumorchirurgie ohne Bestrahlung des autologen Blutes eingesetzt wurde. Mit der MAT und der anschließenden Leukozytendepletion ist eine Methode zur Vermeidung von Fremdblut verfügbar, die der Bestrahlung vergleichbar sicher, aber einfacher und deshalb effektiver ist.

A popular approach to select optimal adsorbents is to perform parallel experiments on adsorbents based on an initially decided goal such as specified product purity, efficiency, or binding capacity. To screen optimal adsorbents, we focused on the max adsorption capacity of the candidates at equilibrium in this work because the adsorption capacity of each adsorbent is strongly dependent on certain conditions. A data-driven machine learning tool for predicting the max adsorption capacity (Q

Antimicrobial resistance has silently turned into one of the biggest threats to global health, marking the fall of the Golden age of antibiotics. In the search for antibiotic replacement or enhancement, plant-derived natural compounds have attracted lots of interest. Even though firmly believed, the low-resistance tendency of pathogenic bacteria against plant extracts has been scarcely demonstrated. In this study, we investigated the antibacterial activities of diethyl ether extracts from six medicinal plants grown in Viet Nam against Staphylococcus aureus and its variants, which were in vitro adapted to the same extracts. After 30 passages of S. aureus growing under sub-lethal concentrations of plant extracts or antibiotics, the bacteria slowly adapted to the extracts while rapidly resisting the antibiotics. Most of the resulting strains obtained from the adaptation to plant extracts were collaterally sensitive to antibiotics. In contrast, antibiotic-adapted strains showed cross-resistance to both antibiotics and extracts. The findings provided evidence of the low-resistance tendency of S. aureus to antimicrobial plant extracts. It is the first time a collateral antibiotic sensitivity of S. aureus adapted to natural compounds has been observed, suggesting an alternative approach to fight antibiotic resistance.

Xao tam phan (XTP), a Paramignya genus of the Citrus family, is a renowned medicinal plant in Southeast Asian countries, including Vietnam, and is associated with treating cancer, hepatitis, diabetes, and nose infections. Extraction is a key operation in the preparation of XTP extracts rich in phytochemical compounds. Recently, the application of ultrasound has resulted in a large number of successes in the extraction of medicinal plants for improvement in yield and quality of extracts. Until present, ultrasonic-assisted extraction has not been favored for XTP. In this work, the effect of sonication treatment on collecting the extract of total phenolics and saponin from the XTP root was investigated, then the experimental data were analyzed and optimized by Response Surface Methodology (RSM). The results indicated that the optimal sonication power, temperature, and time were 200 W, 58°C, and 10 min, respectively. Under those conditions, the total phenolic and saponin contents in the XTP extract were maximized and validated to be 20.70 ± 0.77 mg GAE/g dried matter and 326.30 ± 2.03 mg EE/g dried matter, respectively. For comparison, a higher extraction yield of ultrasound-treated samples, in terms of total phenolics (~ 27%) and total saponin (~ 76%), was found as compared to the untreated ones. In conclusion, the results reveal that the application of ultrasound on xao tam phan root significantly enhanced the phytochemical contents during extraction.

The aim of this study was to recover Sc as the main product and Fe as a by-product from Hungarian bauxite residue/red mud (RM) waste material by solvent extraction (SX). Moreover, a new technique was developed for the selective separation of Sc and Fe from real RM leachates. The presence of high Fe content (∼38%) in RM makes it difficult to recover Sc because of the similarity of their physicochemical properties. Pyrometallurgical and hydrometallurgical methods were applied to remove the Fe prior to SX. Two protocols based on organophosphorus compounds (OPCs) were proposed, and the main extractants were evaluated: bis(2-ethylhexyl) phosphoric acid (D2EHPA/P204) and tributyl phosphate (TBP). The results showed that SX using diethyl ether and tri-n-octylamine (N

Multiwalled carbon nanotubes (MWCNTs) were oxidized using a mixture of H

Adsorption in the continuous mode plays a significant role in wastewater treatment. In this study, Mimosa pigra-derived biochar modified with 2 M AlCl

Each year, the global annual production of coconut fibre (CF) is around 350×103 t, while they are utilized for fine art, fertilization, and animal feed. However, there have not seen many engineering applications to utilize these materials. The coir with high cellulose content of over 40 % has potential for high-value engineering applications like fabricating cellulose-based aerogels. Recently, the cellulose aerogel from CF was formed using a sol-gel method in an NaOH/Urea solution, with an anticipated completion time of 7 d due to the time required for gelation and solvent exchange, which might take up to 4 d. This demonstrates that the present approach is subject to several time limitations. To improve this, for the first time, a novel fabrication of aerogels from the CF with chemical pre-treatment in advance has been successfully developed by using polyvinyl alcohol (PVA) and xanthan gum (XTG) as biodegradable binders. The treated CFs are dispersed homogeneously into a PVA/XTG solution, followed by freeze-drying to remove water, leaving behind a highly porous called CF aerogel. The influences of CF content on CF aerogels' physical and mechanical characteristics, as well as oil adsorption and thermal conductivity, have all been thoroughly investigated. For oil removal, the fabricated CF aerogels are surface-modified with methyltrimethoxysilane (MTMS) to enhance their hydrophobicity. This method required 2 times less time and used fewer chemicals while retaining the same oil adsorption capabilities of up to 20 g/g as previous CF aerogel and demonstrating additional good insulation of 0.040 W/(m·K). Thus, this study provides a new novel approach to synthesize an oil-absorbing and insulating CF aerogel.

Peanuts are nutritious foods, however, following harvest and storage, these nuts are prone to mycotoxin contamination. Gamma irradiation is an effective technique in postharvest pest control to kill insects and inhibit mycotoxin biosynthesis. Thus, this study aimed to investigate the effect of doses of gamma ray on oil properties and mycotoxin profile of raw peanut seeds. Seeds were exposure to gamma radiation at 10 and 25 kGy and stored at ambient temperature for 6 months compared to non-treated seeds before storage. Color, hardness, oil content, total sugar, total protein content, peroxide value (PV), malonaldehyde (MDA) and aflatoxin analysis were assessed. According to this finding, no significant differences of color, hardness, oil content, PV, MDA were found among treatments. Aflatoxin inhibition and total sugars of treated gamma irradiation peanuts at 10 kGy were higher than treated peanuts at 25 kGy.

This study developed a heterogeneous catalyst derived from iron slag (IS) waste containing main constituents of FeO, ZnO and SiO2 for Fenton and ozonation processes to remove an azo dye (Reactive Red 24 (RR24)) from aqueous solutions. It was found that heterogeneous catalytic Fenton and ozonation processes with IS catalyst can effectively remove RR24 and degradation kinetic of RR24 followed pseudo-first order kinetic model. The decolorization and mineralization of RR24 were dependent on the solution pH with a maximum efficiency obtained at pH 11 for heterogeneous catalytic ozonation processes (O3/IS, O3/H2O2/IS) and at pH 3 for heterogeneous catalytic Fenton (H2O2/IS). The combination of ozone with IS had synergistic effect on RR24 decomposition. An increase the IS dosage from 0.5 g/L to 1.5 g/L for H2O2/IS and O3/H2O2/IS and from 0.5 g/L to 1.0 g/L for O3/IS could enhance the decolorization and mineralization of RR24. The decolorization efficiency and mineralization degree of RR24 after degradation evaluated through the COD removal efficiency indicated the following order: O3/H2O2/IS > O3/IS > O3 ≈ O3/H2O2 > H2O2/IS. The K values (apparent first-order rate constant values) of pseudo-first order model followed the same sequence as mineralization efficiency of RR24, in term of COD removal. The iron slag (IS) was characterized by various techniques, these being: scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The main degradation mechanism of RR24 by before mentioned treatment systems due to FeO, ZnO and SiO2 constituents of the IS increased O3 decomposition as well as enhanced reaction rate with H2O2 leading to more hydroxyl radicals (*OH) generation, thus RR24 degradation rate was improved. This study demonstrated that iron slag can be successfully used as the heterogeneous catalyst in Fenton and ozonation processes for effective removal of RR24 from aqueous solutions.

Resume Le syndrome d’apnees obstructives (SAOS) de l’adolescent est beaucoup moins etudie que le SAOS de l’enfant malgre une prevalence elevee. Il peut certes etre residuel d’un SAOS de l’enfant traite par adeno-amygdalectomie mais est le plus souvent une pathologie de novo. Les facteurs physiopathologiques associent des voies aeriennes superieures etroites et facilement collabables, parfois une hypertrophie des amygdales pharyngees, palatines voire linguales et frequemment un surpoids ou une obesite. Le bilan ORL est essentiel, tout comme le bilan orthodontique systematique. Ce dernier peut conduire a un traitement specifique d’anomalies dento-faciales susceptibles d’aggraver le SAOS. Le traitement du SAOS de l’adolescent repose essentiellement sur la chirurgie adeno-amygdalienne, rarement completee par la reduction des amygdales linguales et sur le traitement orthodontique. La pression positive continue est rarement necessaire chez les adolescents indemnes de malformations et est reservee aux adolescents obeses, avec un SAOS severe non ameliore par les autres approches therapeutiques. Le traitement du SAOS de l’adolescent s’inscrit dans une prise en charge globale, pluridisciplinaire, prenant aussi en compte ses desordres frequemment associes tels que l’obesite et les anomalies du rythme veille/sommeil.

Stem rot caused by the soil-borne pathogen Scleoritum rolfsii Sacc. is a destructive disease which seriously causes yield loss of groundnut in Vietnam. In this study, the antagonistic bacterial str...

In this study, activated carbon from corncobs was successfully synthesized by hydrothermal carbonization and hydrochemical activation at low temperatures, followed by pyrolysis. A developed method of hydrochemical activation of hydrochar that uses only small amounts of chemicals is a promising approach. After activation, the activator residues in the hydrothermal product can constantly act as a chemical activator during pyrolysis to form corncob-activated carbon (AHC-KOH), which had specific surface area of 965.028 m

The quest for finding an effective photocatalyst for environmental remediation and treatment strategies is attracting considerable attentions from scientists. In this study, a new hybrid material, Cu