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Phan Boi Chau (1867 -1940) foi um conhecido patriota, intelectual, revolucionário, escritor, poeta e educador. O pensamento patriótico de Phan Boi Chau combina pontos de vista sobre a libertação nacional e o desenvolvimento do país do Oriente e do Ocidente com a tradição cultural única das valentes batalhas e sacrifícios do povo vietnamita contra os invasores, a fim de abordar questões históricas e sociais. Suas crenças patrióticas são profundas e profundas em muitos aspectos e, além de compartilharem alguns traços históricos, também possuem qualidades únicas que captam a essência da época.

Antibiotic resistance (AR) is a growing health concern worldwide and the Arctic represents an understudied region in terms of AR. This study aimed to quantify AR genes (ARGs) from effluent released from a wastewater treatment plant (WWTP) in Iqaluit, Nunavut, Canada, thus creating a baseline reference for future evaluations. Water, sediment, and truncate softshell clam (Mya truncata) tissue samples were compared from the wastewater, the receiving environment of Frobisher Bay, and nearby undisturbed freshwaters. The pharmaceuticals and personal care products (PPCPs) atenolol, carbamazepine, metoprolol, naproxen, sulfapyridine, and trimethoprim were found in the wastewater, but the PPCPs were undetectable in the receiving environment. However, the relative abundances of ARGs were significantly higher in wastewater than in the receiving environment or reference sites. Abundances did not significantly differ in Frobisher Bay compared to undisturbed reference sites. ARGs in clams near the WWTP had similar relative abundances as those from pristine areas. The lack of ARG detection is likely due to Frobisher Bay tides flushing inputs to levels below detection. These data suggest that the WWTP infrastructure does not influence the receiving environment based on the measured parameters; more importantly, further research must elucidate the impact and fate of AR and PPCPs in Arctic communities.

Granular materials are made up of smaller particles, manifestation of microstructure results in a macroscopic response of granular material. Understanding the overall mechanical behaviour from microscopic parameters is one of the main challenges in many engineering fields including civil engineering. When modelling this kind of material by Discrete Element Model (DEM) using idealized circular grains, the effects of appropriate sample size and microscopic parameter changes have been a crucial subject. Previous research has primarily relied on the case of purely frictional granular materials. In this paper, we use DEM to investigate the appropriate sample size and the relationship between microscopic parameters and the macroscopic responses of cohesive-frictional granular assemblies by performing a series of biaxial tests. Our findings indicate that a minimum number of particles is required to balance between mechanical behaviour and computing time. In addition, through extensive parametric studies, the paper explores the impact of factors such as interparticle bonds, intergranular friction coefficients, and initial void index on the overall shear behaviour of granular assemblies. Also, the result reveals a strong correlation between shear band formation and the break field of cohesive contact (static variable) and the translations and rotations of grains (kinematic variable).

The simply supported beams are commonly used in practice. They present many advantages in design as well as in fabrication and erection. Because the moment of the beam is not constant along its length, the section needs to vary to use the least amount of raw material. Various optimization methods have been proposed, including web trimming, reducing the width of flanges, or changing the flange thickness. In terms of fabrication and installation, it is preferable to keep the beam height and the flange thickness unchanged, making the second solution the most popular. Previous studies have only discussed the flange-stepped solution. Thus, this article will focus on tapering the beam flange by investigating the optimal parameters in terms of the beam weight. The new formulas to determine these optimal parameters will be proposed. The formulas are then used to calculate the material saved by the method. The outcomes are next compared to those of other optimization methods. The result shows that flange-tapered is the most efficient solution.

De très nombreux ponts du patrimoine bâti sont équipés de câbles de précontrainte extérieure installés soit lors de la construction, soit lors de renforcements. Ces câbles sont généralement composés de torons en acier protégés par une gaine injectée au coulis de ciment. En mettant le béton en compression, les câbles lui permettent de résister aux charges auxquelles il est soumis. Il est alors important de pouvoir connaître la tension résiduelle dans les câbles afin de savoir s’ils assurent toujours leur fonction. Pour cela les méthodes vibratoires sont fréquemment utilisées. La méthode d’essai LPC n◦35 est principalement utilisée en France pour les câbles sur ouvrage. Elle permet d’obtenir la tension d’un câble à partir de différents points de mesure lorsque le câble est suffisamment long pour pouvoir être modélisé par un modèle de corde vibrante. Les principales limites qui empêchent l’utilisation automatique de la méthode sont la localisation des points d’excitation, l’enregistrement des données et l’utilisation de plusieurs points de mesure. Le travail présenté dans cet article propose de s’affranchir de ces limites en déterminant tout d’abord l’ordre des modes associé aux fréquences détectées, puis en résolvant un problème inverse, afin de déterminer la tension et la rigidité en flexion du câble. La prise en compte de la rigidité en flexion et la nécessité de réaliser une seule mesure permettent de détecter la tension de n’importe quel câble de précontrainte extérieure avec une mesure unique. Cette méthode a été validée en laboratoire et testée sur ouvrage. Elle nécessite une estimation de la masse linéique et de la longueur libre du câble.

In the 1980s and 1990s, most bridges in Vietnam employed simple beam for short-span river crossings that did not need navigation and mainly used the reinforced concrete T-beams or pre-stressed concrete. While the T-frame structure that has hang single span is widely applied for rivers that require navigation...The single girder is a basic span made of pre-stressed reinforced concrete T or I cross section, with spacing ranging from 2.2m to 2.6m, and the absence of diaphragms was a common feature of bridges built during this time period. All horizontal crashes almost have happened on the spans that did not have diaphragms. As a result, the impact force is concentrated mostly on the lateral girders, leading to total damage. Thus, researches to evaluate the effect of diaphragms in the distribution of horizontal impact forces as well as minimizing the damage in the span structures are crucial. This study focuses on simulating and studying the influence of the number and position of the diaphragms in terms of stress, deformation and damage when a collision occurs in order to propose additional and repair solutions to enhance the horizontal resistance of span.

The study investigates the decomposition of Chlorpyrifos Ethyl (CE) in tea-growing soils using Biomix under varied conditions, aiming to enhance the safety of agricultural products. Biomix 1 demonstrated a significant capability for degrading CE, particularly at higher temperatures and an optimal pH of 6. It showcased higher microbial density for lignindecomposing organisms at 4.68×105 CFU/g for cellulose decomposition, 3.6×105 CFU/g for hemicellulose, and 2.5×105 CFU/g for lignin, indicating robust biodegradation potential. An intriguing outcome was Biomix 2’s improved performance with nitrogen supplementation, reaching over 96% degradation efficiency for CE at a concentration of 150ppm. Temperature fluctuations within the composting bins pointed to the thermophilic nature of the degrading microbes, with an initial increase to 35°C and subsequent stabilization, suggesting a vigorous decomposition phase followed by a plateau due to substrate depletion. These findings indicate that microbial composting at optimized moisture (60%) and pH levels can significantly degrade CE, with a higher degradation rate observed at 37°C compared to 25°C. Biomix amendments and maintained conditions reflect the practical application potential, aligning with the common agricultural CE concentrations of 120-150ppm. This study underlines the viability of using microbial composting as a sustainable and effective strategy for the bioremediation of pesticide-contaminated agricultural soils, with promising implications for environmental safety and public health.

The small-strain and electromagnetic behaviors of soils significantly change due to compression. The objective of this study was to investigate the small-strain stiffness and electrical resistivity of diatomaceous sand by modifying the conventional setup of oedometer tests (1D-compression tests). The specimens used were pure sand and sand with 20% diatoms by weight. The vertical displacement was directly observed using a digital gauge at the top of the compression cap during compression. At the end of each loading step, shear waves (S-waves) are measured using a pair of bender elements installed on the top and bottom compression caps. In addition, electrical resistance was measured using a pair of electrodes installed horizontally in the middle of the compression cylinder. The test results show that the compression index increased but the swelling index decreased according with the increase in the amount of the small and crushable diatom particles. The presence of diatom particles weakened the interparticle contacts and softened the soil skeletons. In addition, the electrical resistivity increased with the increase in diatom contents, which increased the surface conduction. Our work suggests that the S-wave velocity and electrical resistivity of diatomaceous sand can be characterized by modifying the conventional oedometer tests.

The paper describes the development of a high-pressure isotropic cell for studying the environmental degradation of low porosity clayey rocks. Air permeability measurements are used in this device as a tool to evaluate rock degradation in unsaturated rock specimens caused by mechanical, hydraulic and chemical paths. A modified equation, based on the air pressure decay method proposed by Yoshimi and Osterberg (1963), is presented. The proposed method is applied to an Australian clayey shale. Estimated values of air permeability are compared against those calculated using the original method which, in the case of low porosity rocks, seems to provide unrealistic values when the air pressure in the vessel decays beyond 50%.

Public investment is one of the important and decisive factors for the economic development process in Vietnam. It involves the government's investment in public programs, projects, and investment subjects. The medium-term public investment plan for the 2021-2025 period needed VND 2.87 million billion, with priority given to important and key sectors of the economy, including transport infrastructure. The allocated capital for the transport sector accounts for the highest proportion (42.9%) but the development of synchronous and modern infrastructure has not yet met the requirements [1]. Currently, the disbursement work is slow and faces many obstacles, affecting the efficiency of capital use. According to the report of the Ministry of Transport, in the period 2016-2020, the disbursement rate for traffic works reached 69% [2]. Therefore, this article analyzes the current situation of disbursement in the construction of transport infrastructure through reports of government management agencies, previous studies, using SPSS software to quantify criteria affecting this work. Based on that, the authors propose solutions to enhance the disbursement of investment capital in transportation infrastructure construction.

The reliability of a model in ABAQUS depends mainly on the experience of the modeler. For the problem of elastic buckling of a simply supported thin plate in compression, except for the example in ABAQUS’s user manual, which only applies to rectangular plates that are symmetrical in both directions, the current proposed models are personalized and untested. Therefore, the purpose of this paper is to verify the currently used models and thereby propose a general model for the problem. For this purpose, different models are created in ABAQUS, and their reliability will be asserted by comparing the results with the theoretical solution of Timoshenko. The critical stresses and buckling coefficients of models are the values to be obtained and used for comparison. The results show that the model outlined in ABAQUS’s user manual and the model proposed in the paper match the theoretical solution, while other models have significant differences. The proposed model is more general than that of ABAQUS’s manual, and it is applied to an example of a trapezoidal plate. The knowledge obtained from the proposed model can be applied to the modeling of other forms of structure.

In this research, we have mainly focused on the controlled synthesis, and properties of micro/nanosized ferrite and hexaferrite powders by the polyol process. They are Fe3O4-type Sr-Fe-O oxide and SrFe12O19 with the structure and magnetic properties by SEM, XRD, and VSM measurements. After heat treatment, it was discovered that Sr element was gradually fully incorporated into Fe3O4 for the formation of the original hexaferrite structure of SrFe12O19 at 950°C.

In order to improve the efficiency of transportation infrastructure maintenance, it is proposed to introduce an insurance fund that performs two functions: accumulation of payments with different frequency and cost for performing various types of maintenance; pays for these types of maintenance as necessary. To mathematically describe the state of the insurance fund, it is proposed to use a special type of risk process. This approach allowed us to introduce maintenance performance indicators in the form of resource-cost and financial risks, taking into account the possibility of non-performance of maintenances due to lack of financial resources. A modeling program based on the event approach was created in the MATLAB environment to study these indicators. Computational experiments with the modeling program allowed us to draw conclusions that, in order to minimize the risk values, preference should be given to the option when the shares and frequency of payments to the insurance fund are determined based on the type of maintenance and initial data.

Background: The Kappa variant is designated as a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of interest (VOI). We identified 195 Kappa variant cases in a region of British Columbia, Canada—the largest published cluster in North America. Objectives: To describe the epidemiology of the Kappa variant in relation to other circulating SARS-CoV-2 variants of concern (VOC) in the region to determine if the epidemiology of the Kappa variant supports a VOI or VOC status. Methods: Clinical specimens testing positive for SARS-CoV-2 collected between March 10 and May 2, 2021, were screened for the detection of known circulating VOCs; approximately 50% of specimens were subsequently selected for whole genome sequencing (WGS). Epidemiological analysis was performed comparing the characteristics of Kappa cases to the main circulating variants in the region (Alpha and Gamma) and to non-VOC/VOI cases. Results: A total of 2,079 coronavirus disease 2019 (COVID-19) cases were reported in the region during the study period, of which 54% were selected for WGS. The 1,131 sequenced cases were categorized into Kappa, Alpha, Gamma and non-VOC/VOI. While Alpha and Gamma cases were found to have a significantly higher attack rate among household contacts compared to non-VOI/VOC cases, Kappa was not. Conclusion: Epidemiological analysis supports the designation of Kappa as a VOI and not a VOC. The Alpha and Gamma variants were found to be more transmissible, explaining their subsequent dominance in the region and the rapid disappearance of the Kappa variant. Variant surveillance strategies should focus on both detection of established VOCs and detection of potential new VOCs.

Contexte : Le variant Kappa est désigné comme un variant d’intérêt (VI) du coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2). Nous avons recensé 195 cas du variant Kappa dans une région de la Colombie-Britannique, au Canada, le plus grand agrégat spatio-temporel publié en Amérique du Nord. Objectifs : Décrire l’épidémiologie du variant Kappa en relation avec d’autres variants préoccupants (VP) du SRAS-CoV-2 en circulation dans la région afin de déterminer si l’épidémiologie du variant Kappa demande un statut de VI ou de VP. Méthodes : Les échantillons cliniques qui se sont avérés positifs pour le SRAS-CoV-2 collectés entre le 10 mars et le 2 mai 2021 ont été examinés pour la détection des VP circulants connus; environ 50 % des échantillons ont ensuite été sélectionnés pour le séquençage du génome entier. Une analyse épidémiologique a été réalisée en comparant les caractéristiques des cas Kappa aux principaux variants circulant dans la région (Alpha et Gamma) et aux cas non VP/VI. Résultats : Au total, 2 079 cas de maladie à coronavirus 2019 (COVID-19) ont été signalés dans la région pendant la période d’étude, dont 54 % ont été sélectionnés pour le séquençage du génome entier. Les 1 131 cas séquencés ont été classés en Kappa, Alpha, Gamma et non VP/VI. Alors que les cas Alpha et Gamma se sont avérés avoir un taux d’attaque significativement plus élevé parmi les contacts familiaux par rapport aux cas non VI/VP, ce n’était pas le cas pour le variant Kappa. Conclusion : L’analyse épidémiologique soutient la désignation du variant Kappa comme un VI et non un VP. Les variants Alpha et Gamma se sont avérés plus transmissibles, ce qui explique leur domination ultérieure dans la région et la disparition rapide du variant Kappa. Les stratégies de surveillance des variants doivent mettre l’accent à la fois sur la détection des VP établis et sur la détection de nouveaux VP potentiels.

Contexte : En avril 2021, une éclosion d’Escherichia coli (E. coli) O103 producteurs de Shiga-toxines (STEC) a été décelée chez des patients de deux hôpitaux de Victoria, en Colombie-Britannique. L’objectif de cette étude est de décrire l’enquête sur cette éclosion et de déterminer les problèmes de salubrité des aliments pour les produits à haut risque préparés pour les populations vulnérables. Méthodes : Des cas confirmés d’E. coli O103 ont été signalés à l’unité des maladies transmissibles d’Island Health. Le laboratoire provincial de santé publique a procédé au séquençage du génome entier des isolats des cas confirmés, conformément à la pratique courante pour les STEC en Colombie-Britannique. Les renseignements sur l’exposition ont été obtenus par l’entremise d’entretiens avec des cas et de l’examen des menus des hôpitaux. Les autorités sanitaires fédérales et locales ont procédé à une inspection de l’usine de transformation de la source suspecte. Résultats : Six cas confirmés d’E. coli O103 ont été décelés, tous liés par le séquençage du génome entier. La majorité des cas étaient des femmes (67 %) et l’âge médian était de 61 ans (intervalle de 24 à 87 ans). Tous les cas confirmés étaient des patients hospitalisés ou en consultation externe dans deux hôpitaux et ont été exposés à du céleri haché cru dans des sandwichs préparés fournis par les services alimentaires de l’hôpital. Un transformateur local fournissait le céleri haché exclusivement aux deux hôpitaux. L’analyse du produit chez le transformateur était peu fréquente, et le rinçage au chlore avait lieu avant le hachage. Nous croyons que la propagation de la contamination résiduelle par E. coli lors du processus de hachage, en plus des abus de température dans les hôpitaux, ont contribué à cette éclosion. Conclusion : Les légumes crus, comme le céleri, sont une source potentielle de STEC et présentent un risque pour les populations vulnérables. Les recommandations issues de cette éclosion comprennent des tests plus fréquents chez le transformateur, une révision du processus de chloration et de hachage et une révision des pratiques des services alimentaires de l’hôpital pour atténuer les abus de température.

Background: In April 2021, a Shiga toxin-producing Escherichia coli (E. coli) (STEC) O103 outbreak was identified among patients at two hospitals in Victoria, British Columbia (BC). The objective of this study is to describe this outbreak investigation and identify issues of food safety for high-risk products prepared for vulnerable populations. Methods: Confirmed cases of E. coli O103 were reported to the Island Health communicable disease unit. The provincial public health laboratory conducted whole genome sequencing on confirmed case isolates, as per routine practice for STEC in BC. Exposure information was obtained through case interviews and review of hospital menus. Federal and local public health authorities conducted an inspection of the processing plant for the suspect source. Results: Six confirmed cases of E. coli O103 were identified, all related by whole genome sequencing. The majority of cases were female (67%) and the median age was 61 years (range 24–87 years). All confirmed cases were inpatients or outpatients at two hospitals and were exposed to raw minced celery within prepared sandwiches provided by hospital food services. A local processor supplied the minced celery exclusively to the two hospitals. Testing of product at the processor was infrequent, and chlorine rinse occurred before mincing. The spread of residual E. coli contamination through the mincing process, in addition to temperature abuse at the hospitals, are thought to have contributed to this outbreak. Conclusion: Raw vegetables, such as celery, are a potential source of STEC and present a risk to vulnerable populations. Recommendations from this outbreak include more frequent testing at the processor, a review of the chlorination and mincing process and a review of hospital food services practices to mitigate temperature abuse.

Background: In 2018, a Shiga toxin–producing Escherichia coli O121 outbreak that affected seven individuals was associated with raw milk Gouda-like cheese produced in British Columbia, Canada. Objectives: To describe the E. coli O121 outbreak investigation and recommend greater control measures for raw milk Gouda-like cheese. Methods: Cases of E. coli O121 were identified through laboratory testing results and epidemiologic surveillance data. The cases were interviewed on exposures of interest, which were analyzed against Foodbook Report values for British Columbia. Environmental inspection of the dairy plant and the cheese products was conducted to ascertain a source of contamination. Whole genome multi-locus sequence typing (wgMLST) was performed on all positive E. coli O121 clinical and food isolates at the provincial laboratory. Results: Four out of the seven cases consumed the same raw milk Gouda-like cheese between August and October 2018. The implicated cheese was aged longer than the required minimum of 60 days, and no production deficiencies were noted. One sample of the implicated cheese tested positive for E. coli O121. The seven clinical isolates and one cheese isolate matched by wgMLST within 6.5 alleles. Conclusion: Raw milk Gouda and Gouda-like cheese has been implicated in three previous Shiga toxin–producing E. coli outbreaks in North America. It was recommended product labelling to increase consumer awareness and thermization of milk to decrease the risk of illness associated with raw milk Gouda and Gouda-like cheese.

Contexte : En 2018, une éclosion d'Escherichia coli O121 produisant la toxine de Shiga avec sept cas a été associée à la production de fromage au lait cru de type Gouda en Colombie-Britannique, au Canada. Objectifs : Décrire l'enquête sur l'éclosion d'E. coli O121 et recommander des mesures de contrôle plus strictes pour les fromages au lait cru de type Gouda. Méthodes : Les cas d'E. coli O121 ont été identifiés grâce aux résultats d'analyses en laboratoire et aux données de surveillance épidémiologique. Ils ont ensuite été interrogés en fonction de l'exposition d'intérêt, puis analysés en fonction des valeurs du Rapport Foodbook pour la Colombie-Britannique. Une investigation a été effectuée dans l'usine laitière et des prélèvements ont été effectués dans les produits de fromage afin de déterminer la source de contamination. Le typage de séquence multilocus pour le génome entier a été effectué sur tous les isolats cliniques et alimentaires positifs pour E. coli O121 au laboratoire provincial. Résultats : Quatre des sept cas avaient consommé le même fromage au lait cru de type Gouda entre août et octobre 2018. Ce fromage avait été affiné pendant une période supérieure au minimum requis de 60 jours, et aucun défaut n'a été constaté dans sa production. Un échantillon du fromage visé a cependant obtenu un résultat positif à l'analyse de dépistage de la bactérie E. coli O121. Sept isolats cliniques et un isolat de fromage ont été jugés identiques par typage de séquence multilocus pour le génome entier avec une différence de 0 à 6,5 allèles. Conclusion : Le Gouda au lait cru et les fromages de type Gouda au lait cru avaient déjà été impliqués dans trois éclosions antérieures d'E. coli producteur de toxines Shiga en Amérique du Nord. Il a donc été recommandé d'étiqueter les produits afin de sensibiliser les consommateurs au risque et de thermiser le lait afin de réduire le risque de maladie associé au Gouda au lait cru et au fromage de type Gouda au lait cru.

This paper has been written in response to the need to identify the factors of environment affecting students’ attitudes on startups intention within the period 2019-2020, at the time of the COVID-19 breakout. For this purpose, the research was conducted on the sample of 2,141 students in twelve universities in Ho Chi Minh City. This research finds out what motivates students to learn, shape start-up ideas as to start a new business, and how an environment approach affects students’ startup intention as to gain confidence and positive feelings about the entrepreneurship. This study shows that both general and task environment, as well as positive and negative attitudes directly and indirectly affected students’ startup intention. The implication of the findings of this study suggests that the government and universities should pay more attention to environment factors because of its providing opportunities and support to students’ startup intention.

The paper describes the inadequacies of cycled head-down load tests on two barrettes and one bored pile installed in soft clay soil region in Binh Thanh district, and district 7, Ho Chi Minh City, Vietnam, respectively. The soil profile of these sites consisted of layers of organic soft clay and silt from 22.5 m to 28.6 m depth on compact silty sand or semi-stiff to stiff clays to about 60 m depth and followed by dense to very dense sand. The cross-section area of two barrettes located on the Tan Cang complex area was 2,800 mm by 800 mm, which were constructed using the bucket drill technique with bentonite slurry into 65 m depth. The bored pile of the Lakeside project in district 7 having a pile diameter was 1200 mm and 80 m depth. All instrumented piles were attached from ten to eleven strain gages levels along the pile shaft to record the deformation data during the load tests. The strain data analysis shows that the shaft frictions of pile portions located in the soft clay soil regions were increased dramatically, and the base resistances were smaller expected by the setting-up of Kentledge and the cyclic loading tests.

In the present study, a novel quadrilateral element, namely SQ4C, combined with the Timoshenko beam element is proposed for the static and buckling analyses of stiffened plate/shell structures. The idea behind these elements is a treatment for shear locking as well as membrane locking arising from the framework of the first-order shear deformation theory and a mesh with curved shell geometry. Formulations with eccentricity are also presented in this paper for the general case. The static and buckling analysis solutions and comparison with other available numerical solutions are presented to illustrate the robustness of the proposed elements to stiffened plate/shell structures. This paper also helps engineers in supplementing their knowledge.

Transarterial chemoembolization is a standard locoregional therapy for intermediate stage hepatocellular carcinoma. The tumour is typically supplied by the hepatic arteries, however, extrahepatic collateral arteries may significantly contribute parasitic blood supply to the tumour. Large and exophytic tumour, subcapsular location, direct invasion and adhesion to adjacent organs, hepatic artery dissection, stenosis and occlusion resulting from multiple embolizations are risk factors of extrahepatic collateral arteries. Understanding the prevalence and prediction of these parasitic supplies on pre-procedural imaging is of utmost importance for optimizing technical and clinical outcomes.

his paper presents the right-left symmetry of the CS and max-min CS conditions on nonsingular rings, and generalization to nonsingular modules. We prove that a ring is right nonsingular right CS and left Utumi if and only if it is left nonsingular left CS and right Utumi. A nonsingular Utumi ring is right max (resp. right min, right max-min) CS if and only if it is left min (resp. left max, left max-min) CS. In addition, a semiprime nonsingular ring is right max-min CS with finite right uniform dimension if and only if it is left max-min CS with finite left uniform dimension.

The 4th industrial revolution is taking place worldwide and has a strong impact on economic, cultural, and social activities. In recent times, digital transformation has become the top concern for businesses in Vietnam in the Industrial Revolution 4.0. According to the National Digital Transformation Program to 2025, with the Prime Minister’s 2030 orientation, the digital economy aims to achieve 20% of GDP by 2050 and 30% of GDP by 2030. In the construction sector, construction accounts for 30-40% of the total social investment capital, which contributes to increasing productivity, increasing the competitiveness of construction products, and is an important resource contributing to national economic development. For construction enterprises, this contributes to improving their competitiveness. Guidelines and policies of the Government and the Ministry of Construction are available, but digital transformation in the construction industry is still slow. The article analyzes the achieved results as well as difficulties and challenges, thereby proposing solutions to promote the digital transformation of the construction industry.

Old apartment buildings in Hanoi were built before 1954 and from around 1960 to 1994 with 1600 apartments. Due to the end of construction lifespan, components are sinking, cracking, and tilting, combined with households expanding and repairing themselves, so many buildings are seriously damaged and dangerous, needing to be renovated and rebuilt in the near future to ensure residents’ safety. This work cannot slow down any longer. From 1999 until now, despite great efforts, Hanoi has only renovated and rebuilt 19 apartments (about 1.2%). The main reason is due to conflicts between the interests of the household community and the real estate investors. Contributing to resolving the above contradiction and promoting the speed of redevelopment, this study proposes a community-led model to rebuild old apartment buildings in Hanoi, Vietnam.

The novel and facile multi-stage method was used for the conversion of bamboo into nanocellulose and single cell protein. Firstly, the bamboo chips were treated with sodium hydroxide solution followed by hydrogen peroxide bleaching for obtaining cellulose pulp with a brightness of 80% ISO. In the second stage, the obtained bleached cellulosic pulp was achieved with a dilute sulfuric acid and hydrogen peroxide followed by filtration for obtaining the sugar solution, which than was treated and used for Candida utilis cultivation, and nanocellulose, which than was submerged purification and refining for obtaining nanocellulose fibers. The optimal conditions of the yeast cultivation were dertermined for obtaining the single cell protein with protein content of approx. 49.5 wt.%. For isolation of nanocellulose with fiber diameter < 100 nm were proposed: concentration of hydrogen peroxide 0.25 wt.%, the concentration of sulfuric acid 0.75 wt. %, liquor to cellulose ratio 8 to 1, temperature 140oC, time 120 min. The characteristics of nanocellulose were studied by SEM, FTIR, and XRD.

With the necessity of diversifying alcoholic beverages, cider has become a kind of drink that can fulfill this demand. This is because the cider will be diversified depending on the kinds of fruit that are chosen to be used for the cider fermentation. Therefore, this study aims to investigate the effects of dilution ratio, Brix, pH, and yeast concentration on the production of cider from king mandarin (Citrus nobilis Lour.), and to evaluate the analytical characteristics and antioxidant activity of the product. After the investigation, it can be claimed that the dilution of the juice causes the ethanol content to decrease, whereas the increase of Brix, pH, and yeast concentration makes the ethanol content increase. However, the proportional increase in the ethanol content with Brix, pH, and yeast concentration has its limitations. Specifically, when the Brix and the yeast concentrations were, respectively, higher than 16°Brix and 0.04%, the ethanol content tended to maintain the same. This is also the same when the pH was lower than 4.5. In addition, by using the DPPH and ABTS●+ methods, the antioxidant activity of cider is estimated to be lower than the one of the juice before fermentation, which is smaller than 3.78 times for the DPPH method and 3.76 times for the ABTS●+ method.

To repel mosquitoes, there have been many highly effective chemical repellent products, but they carry the potential risk of being unsafe for humans and harmful to the environment. Insect repellent products derived from natural sources that are safe for humans and environmentally friendly are becoming increasingly popular. PMD is a broad-spectrum and effective insect repellent but is present in small amounts in the Eucalyptus citriodora essential oil (EO). In this study, we investigated and evaluated the conditions for synthesizing PMD from EO raw materials in an acidic environment to achieve the highest synthesis efficiency of 76.3%, and the PMD product was 96.4% pure after being converted for 5 hours at 50°C in a 0.25% H2SO4 solution. Additionally, the study also separated the two cis and trans isomers of PMD by column chromatography and determined their structures using infrared spectroscopy (IR) and nuclear magnetic resonance (NMR).

The article proposes the development of a numerical method for calculating multilayer beams, based on the theory of composite rods by A.R. Rzhanitsyn. The modification of this theory is to simplify the calculation model for a determined class of structures. It is considered multilayer beams composed of same layers of rectangular cross section, with the same physical and mechanical characteristics. The stiffness of all connecting seams is taken equal. In the research the hypothesis of a functional relationship between shear forces in the seams of the structure is taken. This allows the authors to significantly reduce the dimension of the system of resolving differential equations, from n + 2 equations to three for any finite number of layers. Where n -is the number of seams, and, accordingly, the number of shear forces to find in the seams according to the A.R Rzhanitsyn model, n + 1 is the number of layers. A comparison of three models of the above dependence is given. The numerical methodology is based on the approximation of differential equations by difference equations of the method of successive approximations (MSA). This methodology has proven itself well in the calculation of beams, plates, shells for the action of static loads, in calculations in a dynamic setting and for stability, on an elastic foundation. Including multilayer beams and plates. It allows to take into account the finite discontinuities of the load parameters, stiffness parameters of the structure and foundation. The described methodology can find application in the practice of design organizations and enter the educational courses of higher educational institutions of the construction profile.

Nowadays, the economy is based on the linear method in which people harvest, consume, and dispose of materials and buildings, affecting the environment negatively. Circular economy (CE) in cities aims to maintain and value as well as optimize the use of city assets and products through circular actions: sharing, recycling, refurbishing, re-using, replacing, and digitizing. CE will address the linear system inadequacies and move towards a sustainable society. Mainly, housing is considered a driver of economic, social, and civic development. It is also considered as one of the biggest sectors adding to these adverse effects by growing energy and water consumption, sewage burdens, and flooding. Therefore, the housing study toward CE's aims is the top priority for the circular economy transition. Most of the current CE research focuses on design for the disassembly and recycling of material. Instead, this study aims to further the investigation of flexibility and adaptability in housing as part of CE. By using quanlitative mothods (Literature Review, Theoretical Analysis, Secondary Data Analysis), this paper proposes the state-of-art housing design approaches that meet the requirements for the capacity of housing can adapt to different residents’ and societal needs over time to ensure that the building and its materials remain in circulation for as long as possible. The results contribute to real estate development in the formation of environmentally sustainable cities, as well as toward Circle Economy in the context that the yearly supply of homes continues to increase due to urbanization.

In the railway network plan for the period of 2021 – 2030, with a vision to 2050, the Vietnamese Government aims to complete the North – South high-speed railway route – the first phase (from 2025 – 2030) and invest in Hanoi – Vinh and Nha Trang – Ho Chi Minh City routes. In order to realize the above goal, the Ministry of Transport has agreed with the Ministry of Planning and Investment to submit the “Project of investment policy on construction of North – South high-speed railway” to the Politburo in 2023. However, in reality, it is extremely difficult to mobilize enough resources to complete the “super project”. Choosing the right financing mechanism is critical to the success of the project. The article studies the experience of capital mobilization in a number of countries with developed high-speed railway systems or whose economies and societies have many similarities with Vietnam; analyzes achievements and difficulties. Based on the actual conditions of Vietnam, we can draw important lessons and recommend forms of implementation consistent with actual policies and resources, in order to invest on schedule and achieve the results in accordance with the tasks set forth by the Government.

Sustainable architecture trends influence the choice of materials both indoors and outdoors, making timber a strongly preferred material. Increasing numbers of architects, developers, governments, educational institutions and corporations are embracing wood, since timber replace other construction materials in many structures while providing the same functionality. The combination of a rising concern about global warming and sustainability; a growing desire to preserve traditional Vietnamese culture; recent scientific and technological advances which have made wood an even more versatile building resource; and an international push for increased use of timber in construction, makes Vietnam’s timber architecture perfectly placed for expansion. The article presents findings on why using timber is good for environment and the use of timber in design as well as timber revolution in construction and architecture in Vietnam. By applying new technology and methods, and through using sustainably-sourced plantation wood, there is huge potential for the revival of wooden architecture in Vietnam. This would have significant environmental and economic advantages for the country and most importantly, create opportunities to continue the long-standing tradition of using wood for thousands of years in the construction and architectural works, from traditional houses to public buildings for community in Vietnam.

When it comes to the typical image of an urban area, public space is considered a place that many people refer to because it is a place where cultural, social and entertainment activities often take place in daily life. Along with the trend of global integration and urbanization, the current Vietnamese urban architecture, especially the traditional urban spaces, is being gradually lost because of the influences of new architecture imported from the other countries. In terms of management, the choice of development and preservation of identity is always a difficult problem when taking into account the economic and social development of the city. It is necessary to include the goal of harmonious development of urban identity in the planning and design process. Through synthesizing and surveying local cultural values that have been evaluated and analyzed to distill some outstanding tangible and intangible values, and at the same time recreate urban public spaces in order to regenerate landscape at Ha Thanh river, in Dieu Tri area - Quy Nhon city - Central region - Vietnam.

In recent decades, the speed of construction, expansion, and development of smart cities by humans has been increasing faster, thanks to new technologies. However, alongside the fantastic development of new technologies also comes negative impacts such as climate change. One of the characteristics of climate change is the changing thermal comfort of humans living in the city. Heat stress is a feature of the urban heat island phenomenon. Congestion of airflows within the urban area causes localized hot areas, causing a temperature difference of 2-3 degrees between the areas inside the city and the suburbs. This study presents a method for determining surface temperature and the location of heat islands based on Google's cloud computing platform. The platform uses a combination of satellite imagery, Earth observation data, and machine learning algorithms to allow users to identify and measure changes in land use, ecosystems, and climate patterns at a global scale. Google Earth Engine enables researchers and organizations to process enormous amounts of data with short turnaround times. The method described in the article allows the analysis and retrieval of data in the large dataset of the Landsat 8 satellite. By determining the location of heat islands, the government, policymakers, and planners can develop plans to cope with the urban heat island phenomenon and improve the quality of life for residents.

In recent years, there has been a remarkable rise in the number of certified green building projects in Vietnam, with industrial buildings accounting for the largest portion. The purpose of this research is to evaluate the ability to achieve points of industrial buildings in some green building systems under specific conditions of Vietnam. Another aim of the study is to point out the distinct features of industrial buildings that influence their design, including heavy industry, light industry, and industrial buildings with cleanrooms. Accordingly, this will contribute to increasing the number of industrial buildings that achieve green certification in the future. The study uses a mixed-methods approach, including expert interviews, field surveys, and meta-analysis. The research results will serve as a reference document for sustainable development-oriented design consultants and for organizations establishing green construction criteria systems to be able to upgrade to newer versions with higher adaptability for industrial works.

Shrimp farming has emerged as a multi-billion-dollar industry in our country, creating numerous economic benefits. However, this sector has several negative environmental impacts. Recent studies on the utilization of microalgae for wastewater treatment are of current interest due to their environmental remediation ability, as well as their potential to generate economic value from the biomass produced after treatment. This study aimed to evaluate the wastewater treatment efficiency of Chlorella Vulgaris using a PMBR membrane photobiological model in shrimp aquaculture. The evaluation process included an acclimatization phase and a treatment effectiveness evaluation phase, which lasted a total of 101 days. Algae biomass, the removal efficiency of COD, N-NO -, N-NO -, N-NH +, and P-PO 3-, and membrane fouling behavior were analyzed. The initial results demonstrated that the algae were well-adapted to shrimp aquaculture wastewater. The removal efficiency of N-NO -, N-NO -, N-NH +, and P-PO 3- and COD was 88.55%, 76.15%, 84.58%, 78.07%, and 81.33%, respectively. The algae biomass steadily increased from 91.3 mg/L to 327.69 mg/L, reaching an average level of about 208 mg/L. Additionally, the transmembrane pressure (TMP) evaluation indicated that the necessary time for membrane fouling removal was approximately 25-26 days.

In recent 10 years, object recognition technology has been widely developed with many solutions given with high practical applications. However, with the development of digital devices, the resulting images can be provided from a variety of sources: photos taken (or video captured) directly from living entities, photos printed on paper or photos (video) is displayed on the computer screen or mobile phone. Therefore, the image detection obtained from the camera system directly from the living entity or from images are printed/displayed to determine the correct object is the problem posed. The article focuses on the issue of anti-spoofing of human faces with the content outlining the measures applied in the banking system, the access monitoring system in accordance with the previous registration of these faces there. The purpose is to validate customer or user information such as: wink test results, response to random challenges, etc. The article evaluates the advantages and disadvantages of these methods, after that proposes an anti-spoofing solution by using 3D camera and combining with convolutional neural network to create a more accurate anti-spoofing system.

Unmanned aerial vehicle (UAV) is a flying device that is integrated with appropriate hardware and software, besides it is also a device to collect and process data to meet the needs and purposes of users. Currently, most drones use GPS technology to determine the flight path, and other sensors on it are used to determine distance, avoid collisions. However, with small, narrow spaces, dangerous environments that humans cannot go into that space, GPS not working, small drones with small hardware devices placed on it to map themselves and navigation would be a suitable solution. In this paper, a method to build a high-performance reconfigurable computing environment model to map drone as well as UAV flying in 3D space is proposed. Mapping based on Boolean formulas with reconfigurable structure and adjustable automatons will generate high-precision maps for efficient robot navigation.

Sir, Porokeratosis is a group of cutaneous diseases presented by epidermal keratinization [1]. Herein, we report the case of a patient with porokeratosis who responded well to carbon dioxide (CO2) laser therapy. A 22-year-old Vietnamese male visited our department with an asymptomatic plaque on the penis present for three months. He denied a family history of similar lesions. A cutaneous examination of the penis revealed an annular, well-circumscribed plaque with slightly raised borders with scales (Fig. 1a). Other mucocutaneous lesions were absent. Fungal microscopy, a rapid plasma reagin (RPR) test, and a Treponema pallidum hemagglutination (TPHA) test were negative. Histological findings revealed a hyperkeratotic lesion with a discrete parakeratotic column. There was the presence of a cornoid lamella, which was a parakeratotic column overlying a small vertical zone of dyskeratotic and vacuolated cells within the epidermis (Fig. 2a). There was also a focal loss of the granular layer. A mild lymphocytic infiltrate could be seen around an increased number of capillaries in the underlying dermis (Fig. 2b). CO2 laser removal was performed. There was no recurrence after a twelve-month follow-up (Fig. 1b). However, a hypopigmented scar was seen. Porokeratosis is an uncommon disorder of keratinization with clinical variants, such as classical porokeratosis of Mibelli, disseminated superficial actinic porokeratosis, linear porokeratosis, and porokeratosis palmaris et plantaris disseminata [2]. Porokeratosis involving the genital areas and other adjacent sites is rare [2]. Genital porokeratosis was first described by Helfman in 1985 [3]. More than 69 cases have been reported in the literature [1]. The pathophysiology of genital porokeratosis remains unknown. It has been supposed that porokeratosis is linked to repeated minor frictional trauma. A benign lesion may transform into squamous cell carcinoma or basal cell carcinoma [4]. However, no malignant transformation of genital porokeratosis has been noted in the literature. Genital porokeratosis manifests itself clinically as classic or plaque-type porokeratosis of Mibelli [2]. Histological findings revealed a cornoid lamella with the absence of a granular layer and dyskeratotic cells in the upper spinous zone [2]. Our case may mimic some annular lesions, such as secondary syphilis, fungal infection, and annular lichen planus. Because a fungal examination and syphilis serology were negative, we could exclude fungal infection and annular secondary syphilis. The distinctive histology of porokeratosis such as a cornoid lamella with a decreased granular layer may help to differentiate between porokeratosis and annular lichen planus [4]. Numerous therapeutic methods of treatment exist, including surgical excision, CO2 laser, cryotherapy, topical retinoids, 5% 5-fluorouracil, vitamin D3 analogs, imiquimod cream, and 3% diclofenac gel [2,5].

In remote sensing, Fuzzy C-Means clustering (FCM) is a robust method in determining membership grades of a pixel belonging to 1 or more classes. This paper proposes a novel approach by using the social spider optimization (SSO) algorithm in solving the search for optimal cluster centers in FCM. Hanoi, the capital of Vietnam, was chosen as a case study because of its spatial complexity. Multispectral satellite datasets of Landsat 8, Sentinel 2A and SPOT 7 were used. The experiment started with the segmentation process, followed by an examination of the model, then the results were compared with several conventional clustering methods. For accuracy assessment, the FCM minimizing objective functions, user and producer accuracies and overall accuracy were used. The results showed that SSO significantly improved the performance of FCM and outperformed the benchmarked classifiers or other common optimization algorithms. It could be concluded that the model was successfully deployed in the study area and could be suggested as an alternative solution for urban pattern detection. In a broader sense, classification methods will be enriched with the active and fast-growing contribution of nature-inspired algorithms.