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Microbial exopolysaccharides (EPSs) are receiving growing interest today, owing to their diversity in chemical structure and source, multiple functions, and immense potential applications in many food and non-food industries. Their health-promoting benefits for humans deserve particular attention because of their various biological activities and physiological functions. The aim of this paper is to provide a comprehensive review of microbial EPSs, covering (1) their chemical and biochemical diversity, including composition, biosynthesis, and bacterial sources belonging mainly to lactic acid bacteria (LAB) or probiotics; (2) their technological and analytical aspects, especially their production mode and characterization; (3) their biological and physiological aspects based on their activities and functions; and (4) their current and future uses in medical and pharmaceutical fields, particularly for their prebiotic, anticancer, and immunobiotic properties, as well as their applications in other industrial and agricultural sectors. [ABSTRACT FROM AUTHOR]

Climate change and global warming incite countries to adopt a sustainable development strategy. Many countries consider environmental policies an efficient tool in such a context. Despite a rich literature on the relationship between environmental regulations and the firm's innovation, it almost relies on its environmental practices, but not the whole interaction between the firm and its stakeholders. This research investigates the nexus between environmental regulations, CSR, and innovation. This research relies on panel data on Vietnamese Small and Medium Enterprises between 2013 and 2015. To investigate whether the LEP 2014 implementation incites firms to be more innovative, either through changes in their environmental practices or CSR strategy, we perform a difference-in-difference estimator. This method could be relevant to explore the causal relations of an intervention or treatment on outcome variables. It also allows us to control for potential biases from the group- and time-invariant factors. Besides, we also provide some robustness estimations, including the placebo test, another measurement of innovation, and the potential endogeneity of Environmental treatments and CSR strategy. We first conduct the firm's innovation, environmental treatments, and CSR indexes. The CSR index includes three components: an environmental treatments index, a working conditions index, and a governance index. Our estimated results likely support the idea that the LEP 2014 implementation incites SMEs to improve their innovation capacity. Indeed, such a regulation obligates firms to enhance both their environmental practices and CSR strategy, which, in turn, encourages them to become more innovative. These conclusions still through different robustness verifications. As a first policy implication, a significant diffusion of the LEP 2014 would be predominant. Second, there would be measures that incite firms to improve their environmental treatment. Besides, while environmental regulations may stimulate innovation, their effectiveness requires supplementation with other incentive measures. For example, it is crucial to have supportive or incentive measures aimed at promoting CSR. Dialogue with stakeholders lies at the heart of an effective CSR strategy. [ABSTRACT FROM AUTHOR]

Given the benefits of task repetition, post-task transcribing and teacher corrective feedback, examining the combined effects of task repetition and post-task teacher-corrected transcribing is promised to produce gains in L2 oral performance. In recognition of this potential, this study examined the effects of task repetition combined with post-task teacher-corrected transcribing (TRPTCT) on the complexity, accuracy, and fluency (CAF) of L2 oral performance and CAF gains over time. On a sample of 27 second year English-majors in a Vietnamese university, they were randomly divided into three groups including TRPTCT, task repetition (TR), and control groups. They later orally performed three picture description tasks, which were measured in terms of CAF. Results showed that the TRPTCT condition was superior to the TR condition at increasing complexity and fluency for the students’ repeated task performances. Additionally, the TRPTCT condition was better at fostering accuracy in verb forms and complexity in terms of clause subordination and length of language production as learning gains in the new task performance. [ABSTRACT FROM AUTHOR]

The relationship between the banking and microfinance sectors is a critical element of financial inclusion in developing countries. Their interaction is supposed to improve the efficiency of the intermediation system as a whole, particularly access to credit for entrepreneurs. Competition is one of the most palpable aspects of this relationship, particularly in developing countries. This article aims to analyze spatial competition between a bank and an MFI. In the Hotelling fundamental model (1929), the geographical distance and high transportation costs grant firms some market power over local buyers in their neighborhoods. We start from this basic model and consider a linear city whose length is normalized at 1. In this city, customers are uniformly distributed, each of whom wants to acquire one unit of credit for financing an investment project. We assume that two types of intermediaries ensure the financing of projects in this market: a bank and an MFI. The bank is located at the left end of the segment and the MFI is on the right end. We investigate a non-cooperative game between the two institutions where competition occurs through price and each player determines its rate of interest by taking the other player's strategy into account. We introduce two additional factors of product differentiation to better account for the reality of the interaction between both sectors: 'psychological distance' and the client's level of education. Our model shows that the competition does not play out only based on transport costs, as in the Hotelling model. When the educational level is relatively high compared to psychological and physical distance, the clientele prefers the bank to the MFI. The bank serves the entire market. However, when the educational level is low compared to the mistrust and physical distance, the clientele will prefer to deal with the MFI rather than the bank. The MFI gets the entire market. The same results arise once the psychological distance dominates physical distance and level of education. However, when the clientele is at a psychological equidistance from both institutions and has an average educational level, the market share is determined by the transport costs and physical distance, as in the Hotelling model. [ABSTRACT FROM AUTHOR]

Food computing has long been studied and deployed to several applications. Understanding a food image at the instance level, including recognition, counting and segmentation, is essential to quantifying nutrition and calorie consumption. Nevertheless, existing techniques are limited to either category-specific instance detection, which does not reflect precisely the instance size at the pixel level, or category-agnostic instance segmentation, which is insufficient for dish recognition. This paper presents a compact and fast multi-task network, namely FoodMask, for clustering-based food instance counting, segmentation and recognition. The network learns a semantic space simultaneously encoding food category distribution and instance height at pixel basis. While the former value addresses instance recognition, the latter value provides prior knowledge for instance extraction. Besides, we integrate into the semantic space a pathway for class-specific counting. With these three outputs, we propose a clustering algorithm to segment and recognize food instances at a real-time speed. Empirical studies are made on three large-scale food datasets, including Mixed Dishes, UECFoodPixComp and FoodSeg103, which cover Western, Chinese, Japanese and Indian cuisines. The proposed networks outperform benchmarks in both terms of instance map quality and speed efficiency. • A novel deep learning model, FoodMask, for real-time food instance counting, segmentation and recognition. • Pixel-level annotation on three food image datasets for performance evaluation. • High food recognition performances at both instance and pixel levels compared to current benchmarks. • Real-time computational speed, surpassing existing approaches on food datasets. [ABSTRACT FROM AUTHOR]

This paper investigates the determinants of demand for higher education mobility from students in developing countries to Europe. Used together with various linguistic relations, we emphasise the relevance of informal and formal networks in explaining resistance to student migration. The former are made up of friends or previous students while the latter are formal partnerships that have been established among higher education institutions. Overall, our results show that, apart from the usual economic considerations, student mobility is strongly correlated with non-monetary factors specific to origin and destination, such as socio-demographic characteristics, individual beliefs, and institutional profiles. [ABSTRACT FROM AUTHOR]

Phosphate minerals have long been used for the production of phosphorus-based chemicals used in many economic sectors. However, these resources are not renewable and the natural phosphate stocks are decreasing. In this context, the research of new phosphate sources has become necessary. Many types of wastes contain non-negligible phosphate concentrations, such as wastewater. In wastewater treatment plants, phosphorus is eliminated by physicochemical and/or biological techniques. In this latter case, a specific microbiota, phosphate accumulating organisms (PAOs), accumulates phosphate as polyphosphate. This molecule can be considered as an alternative phosphate source, and is directly extracted from wastewater generated by human activities. This review focuses on the techniques which can be applied to enrich and try to isolate these PAOs, and to detect the presence of polyphosphate in microbial cells. [ABSTRACT FROM AUTHOR]

The literature presents a growing body of evidence demonstrating the positive effect of probiotics on health. Probiotic consumption levels are rising quickly in the world despite the fluctuation of their viability and functionality. Technological methods aiming at improving probiotic characteristics are thus highly wanted. However, microbial metabolic engineering toolbox is not available for this kind of application. On the other hand, basic microbiology teaches us that bacteria are able to exhibit adaptation to external stresses. It is known that adequately applied sub-lethal stress, i.e., controlled in amplitude and frequency at a given stage of the culture, is able to enhance microbial robustness. This property could be potentially used to improve the viability of probiotic bacteria, but some technical challenges still need to be overcome before any industrial implementation. This review paper investigates the different technical tools that can be used in order to define the proper condition for improving viability of probiotic bacteria and their implementation at the industrial scale. Based on the example of Bifidobacterium bifidum, potentialities for simultaneously improving viability, but also functionality of probiotics will be described. [ABSTRACT FROM AUTHOR]

Highlights: [•] Bifidobacteria viability is improved in a two-compartment scale-down reactor with sub-lethal heat stress. [•] Mild heat stress induces EPS overproduction. [•] EPS protects cells from freeze drying stress. [•] The method has a high scalability potential. [Copyright &y& Elsevier]

Abstract: Recent surveys have shown that the energy consumption in a data center considerably contributes to its operation costs. A remarkable part of the large energy volume consumed in data centers today is due to the over-provisioning of such network resources as switches, links, and servers to meet the stringent requirements on reliability. Therefore performance and energy issues are important factors for the design of large multi-tier data centers that can support multiple services. However, the design, analysis, and experiments of such a large and complex system often suffer from the lack of appropriate experimental infrastructures. In this paper, we firstly propose a new energy saving scheme that combines smart sleeping and power scaling algorithms. An energy analysis model is then proposed to calculate the energy saving bounds in case of low and high traffic utilization. We also present a platform for in-depth analysis of energy-aware data center networks, which is a combination of hardware testbed and emulation. Based on OpenFlow technology, the experimental platform is designed to capture details of energy consumed by all network components such as links, ports, and switches under different scenarios. Analytical and emulation results show that the combined algorithm improves the energy saving under the varied traffic utilization. [Copyright &y& Elsevier]

Food computing has recently attracted considerable research attention due to its significance for health risk analysis. In the literature, the majority of research efforts are dedicated to food recognition. Relatively few works are conducted for food counting and segmentation, which are essential for portion size estimation. This paper presents a deep neural network, named SibNet, for simultaneous counting and extraction of food instances from an image. The problem is challenging due to varying size and shape of food as well as arbitrary viewing angle of camera, not to mention that food instances often occlude each other. SibNet is novel for proposal of learning seed map to minimize the overlap between instances. The map facilitates counting and can be completed as an instance segmentation map that depicts the arbitrary shape and size of individual instance under occlusion. To this end, a novel sibling relation sub-network is proposed for pixel connectivity analysis. Along with this paper, three new datasets covering Western, Chinese and Japanese food are also constructed for performance evaluation. The three datasets and SibNet source code are publicly available. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the efficiency of the connections of a hybrid steel–concrete girder is evaluated using the finite element approach. The structural components of the connections and their interactions are fully modeled, and the material nonlinearity considering damage and failure is included in the analysis. The FE model is verified by comparison with the experiment. The parametric study is conducted to investigate the behavior of three different connection types. The moment strength, stiffness, and rotation capacities of various connections are examined. The non-dimensional efficiency factor F eff is proposed in order to evaluate the structural efficiency of the connections. The performance of the various connections is evaluated, and efficient connection details are recommended. [Copyright &y& Elsevier]

Abstract: An orthotropic steel deck designed for carrying light-weight vehicles was investigated to assess its fatigue life. Fracture mechanics analysis was performed with consideration of pre-existing flaws at the fatigue-sensitive region. Three-level models were used to accurately evaluate the stress-intensity factors at the rib-to-diaphragm connection. The crack growth was simulated by numerical integration of the Paris formula. In order to assess the severity of pre-existing flaws at the welded joint of the rib-to-diaphragm connection, the fatigue life of the deck was investigated with different sizes of initial crack. This approach provides a rational quality assessment method for the orthotropic steel deck. [ABSTRACT FROM AUTHOR]

Abstract: A reliable nonlinear finite element model of hybrid steel–PSC beam connection has been developed to investigate the behaviour of the connection. The material nonlinearities of concrete, steel beam, stud, rebar, and tendon were included in the finite element model. The analysis results using the Bézier curve tension stiffening model for concrete compared well with the experimental results. The proposed finite element model offers a reliable and cost-effective alternative to laboratory testing. An extensive parametric study with the changes in a number of transverse rebars and tendon prestress was conducted. The parametric study results showed that the transverse rebar affected the failure mode and that the tendon prestress significantly influenced the load carrying capacity and behaviour of the connection. [ABSTRACT FROM AUTHOR]

Abstract: The buckling of thin-walled composite columns in hat sections and lipped-channel sections reinforced with web stiffener is studied. The columns were composed of symmetric angle-ply laminates. The finite element method was used to investigate the buckling behaviour of the columns. Bifurcation analyses were carried out to obtain the buckling load and mode shapes of the columns. Load-deflection analyses were performed to study the post-buckling behaviour of the columns. The results showed significant effects of ply angle and geometric parameters on the buckling and post-buckling behaviour of the columns. This research provides a guide for improving the loading capacity of composite columns. [Copyright &y& Elsevier]

Abstract: An accurate nonlinear finite element model of the push-out specimen has been developed to investigate the capacity of large stud shear connectors embedded in a solid slab. The material nonlinearities of concrete, headed stud, steel beam and rebar were included in the finite element model. The damage and failure were included in the material model for the headed stud to accurately obtain the ultimate strength of the stud connector. The capacity and ductility of the connection, the load–slip behaviour and failure mode of the headed stud were predicted. The results obtained from the finite element analysis were verified against experimental results of other researches. An extensive parametric study was conducted to study the effect of the changes in stud diameter and concrete strength on the capacity and behaviour of the shear connection. The capacity and ductility of the shear connection obtained from the finite analysis were compared with those specified in EC4 and AASHTO LRFD. It is observed that the AASHTO LRFD specifications overestimated the capacity of the large stud shear connectors, whereas the design rules specified in Eurocode-4 were generally conservative for stud diameters of 22, 25 and 27 mm, and unconservative for diameter of 30 mm. The ductility of the large stud shear connectors is sufficient for practical application in composite bridges. [Copyright &y& Elsevier]

Bacterial exopolysaccharides (EPS) are biopolymers of carbohydrates, often released from cells into the extracellular environment. Due to their distinctive physicochemical properties, biocompatibility, biodegradability, and non-toxicity, EPS finds applications in various industrial sectors. However, the need for alternative EPS has grown over the past few decades as lactic acid bacteria’s (LAB) low-yield EPS is unable to meet the demand. In this case, rhizosphere bacteria with the diverse communities in soil leading to variations in composition and structure, are recognized as a potential source of EPS applicable in various industries. In addition, media components and cultivation conditions have an impact on EPS production, which ultimately affects the quantity, structure, and biological functions of the EPS. Therefore, scientists are currently working on manipulating bacterial EPS by developing cultures and applying abiotic and biotic stresses, so that better production of exopolysaccharides can be attained. This review highlights the composition, biosynthesis, and effects of environmental factors on EPS production along with the potential applications in different fields of industry. Ultimately, an overview of potential future paths and tactics for improving EPS implementation and commercialization is pointed out. [ABSTRACT FROM AUTHOR]

Simple Summary: Aquatic animals are consistently exposed to the threats of environmental deterioration and infection outbreaks because of the excessive use of antibiotics and synthetic drugs. This practice leads to the accumulation of residues in aquatic systems and the development of antimicrobial resistance among pathogens. Nature-based solutions, such as functional feeds containing synbiotics and their active components, such as probiotics, prebiotics, and postbiotics, play a crucial role in maintaining a healthy environment and promoting the well-being of animals in aquaculture. Drawing upon a thorough literature survey and experimental evidence, these agents have been shown beneficial to aquatic animals and their ecosystems. Consequently, these synbiotic agents and related components emerge as promising natural alternatives to traditional synthetic drugs and antibiotics in aquaculture. Aquaculture is a fast-emerging food-producing sector in which fishery production plays an imperative socio-economic role, providing ample resources and tremendous potential worldwide. However, aquatic animals are exposed to the deterioration of the ecological environment and infection outbreaks, which represent significant issues nowadays. One of the reasons for these threats is the excessive use of antibiotics and synthetic drugs that have harmful impacts on the aquatic atmosphere. It is not surprising that functional and nature-based feed ingredients such as probiotics, prebiotics, postbiotics, and synbiotics have been developed as natural alternatives to sustain a healthy microbial environment in aquaculture. These functional feed additives possess several beneficial characteristics, including gut microbiota modulation, immune response reinforcement, resistance to pathogenic organisms, improved growth performance, and enhanced feed utilization in aquatic animals. Nevertheless, their mechanisms in modulating the immune system and gut microbiota in aquatic animals are largely unclear. This review discusses basic and current research advancements to fill research gaps and promote effective and healthy aquaculture production. [ABSTRACT FROM AUTHOR]

To demonstrate that the amount of extracellular polymeric substances (EPS) and the freeze-dried viability of probiotics are correlated. Three strains of probiotics including Lactiplantibacillus plantarum, Lactobacillus acidophilus, and Bifidobacterium bifidum were subjected to environmental challenges, such as temperature, pH, and carbon dioxide. The results indicated that the challenges could stimulate the EPS synthesis of the probiotics. The experimental correlation between the amount of synthesized EPS and the freeze-dried survival rate was also analyzed, and the viability of each of the three strains was represented by the following functions in which the equation of L. plantarum is y = − 0.0336x2 + 2.7059x − 14.849 with R2 = 0.9699, the B. bifidum’s equation is y = − 0.0554x2 + 2.6243x − 13.654 with R2 = 0.9554, and the L. acidophilus’s one was y = 0.0346x2 + 0.5862x − 9.1339 with R2 = 0.9733. This could be a new approach to determining the freeze-dried viability of probiotic strains based on the measured EPS content. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to improve the viability of probiotic bacteria during freeze‐drying by the combination of self‐encapsulation and cryoprotectants. Methods and Results: Lactiplantibacillus plantarum VAL6 and Lactobacillus acidophilus VAR1 were exposed to environmental stresses including temperature, pH and increased CO2 concentration before performing freeze‐drying with the addition of cryoprotectants. The results proved that tested stresses can stimulate the bacteria to synthesize more extracellular polymeric substances to form self‐encapsulation that increases their freeze‐dried viability. In combination with cryoprotectants to form double‐layered microencapsulation, L. plantarum VAL6 stressed at pH 3.5 in combination with whey protein isolate could achieve the highest Improving Cell Viability of 4361‐fold, while L. acidophilus VAR1 stressed at 25oC in combination with alginate gave a maximum Improving Cell Viability of 73.33‐fold. Conclusions: The combination of self‐encapsulation and cryoprotectants significantly improves the freeze‐dried viability of probiotics. Significance and Impact of the Study: This is the first report that uses environmental stress to stimulate extracellular polymeric substance synthesis for self‐encapsulation formation combined with the addition of cryoprotectants to enhance the freeze‐dried survival of probiotics. This could be a novel approach in improving the viability of probiotic strains for various applications. [ABSTRACT FROM AUTHOR]

Environmental factors can alter exopolysaccharide biosynthesis in lactic acid bacteria (LAB). To further clarify this potential relationship, the mRNA expression of genes involved in exopolysaccharide synthesis such as glmU, pgmB1, cps4E, cps4F, cps4J, and cps4H in Lactiplantibacillus plantarum VAL6 under different conditions including temperature, pH, sodium chloride (NaCl), and carbon dioxide (CO2) intensification culture was studied. The transcriptomic data revealed that the exposure of L. plantarum VAL6 at pH 3 increased the expression level of cps4H but decreased the expression levels of pgmB1 and cps4E. Under pH 8, cps4F and cps4E were significantly upregulated, whereas pgmB1 was downregulated. Similarly, the expression levels of cps4F, cps4E, and cps4J increased sharply under stresses at 42 or 47 °C. In the case of NaCl stress, glmU, pgmB1, cps4J, and cps4H were downregulated in exposure to NaCl at 7 and 10% concentrations while cps4E and cps4F were upregulated at 1 h of 10%-NaCl treatment and at 5 h of 4%-NaCl treatment. Remarkably, CO2 intensification culture stimulated the expression of all tested genes. In addition, simultaneous changes in expression of cps4E and cps4F under environmental challenges may elicit the possibility of an association between the two genes. These findings indicated that the expression level of eps genes is responsible for changes in the yield and monosaccharide composition of exopolysaccharides under environmental stresses. [ABSTRACT FROM AUTHOR]

To investigate the effect of environmental stresses on the exopolysaccharide biosynthesis, after 24 h of culture at 37 °C with pH 6.8 and without sodium chloride, Lactobacillus plantarum VAL6 was exposed to different stress conditions, including pH (pHs of 3 and 8) and high sodium chloride concentration treatments. The results found that Lactobacillus plantarum VAL6 exposed to stress at pH 3 for 3 h gives the highest exopolysaccharide yield (50.44 g/L) which is 6.4 fold higher than non-stress. Under pH and sodium chloride stresses, the mannose content in exopolysaccharides decreased while the glucose increased in comparison with non-stress condition. The galactose content was highest under stress condition of pH 8 meantime rhamnose content increased sharply when Lactobacillus plantarum VAL6 was stressed at pH 3. The arabinose content in exopolysaccharides was not detected under non-stress condition but it was recorded in great amounts after 3 h of stress at pH 3. In addition, stress of pH 8 triggered the mRNA expression of epsF gene resulting in galactose-rich EPS synthesis. According to our results, the stresses of pH and sodium chloride enhance the production and change the mRNA expression of epsF gene, leading to differences in the monosaccharide composition of exopolysaccharides. [ABSTRACT FROM AUTHOR]

Introduction: The U.S. Navy Medicine has a long history of conducting global health missions that foster international diplomacy through medical knowledge exchange with a goal of increasing partner nation's health care capacity. Pacific Partnership is an annual U.S. Navy-sponsored joint operation that enhances medical collaboration with participating nations throughout the Indo-Asia-Pacific region. Since 2015, a U.S. Navy Cardiology team has conducted a structural heart disease interventional workshop focused on congenital heart disease with the cardiologists at the Da Nang General Hospital, Da Nang, Vietnam. Herein, we describe the multinational collaborative project including the patient registry we developed to monitor the short- and long-term outcomes of structural heart disease interventions preformed during Pacific Partnership 2015 and 2016.Materials and Methods: Our team developed a sustainable procedural registry with the goal of following the long-term outcomes of cardiac interventions for congenital heart disease in Vietnamese patients. Specifically, the registry was designed to record the changes in symptoms referable to the cardiovascular system and for device placement-associated complications for devices placed in 2015 and 2016 and has been updated annually thereafter.Results: Twelve patients (age range, 7 months to 31 years) underwent successful atrial septal defect closure in 2015 without procedural complications. The follow-up rate was 75% at 1 year and 67% at 2 years, and all devices were in appropriate position with no complications identified. Fifteen patients (age range, 20-66 years) underwent successful atrial septal defect closure in 2016. The follow-up rate was 62.5% at 1 year, and all devices were in appropriate position with no complications identified. Three patients (age range, 5-25 months) underwent successful device closure of the patent ductus arteriosus in 2015 without complications. The follow-up rate was 67% in 2016 and again in 2017. Six patients (age range, 9-74 years) underwent successful patent ductus arteriosus closure in 2016 without complications. The follow-up rate was 67% in 2017, and all devices were in appropriate position with no device-related complications identified.Conclusions: The development of a patient registry during these missions allowed for the longitudinal monitoring of outcomes for cardiac interventions. Notably, treated patients experienced symptomatic improvement without significant long-term procedural complications. Following patients longitudinally across medical missions is of recognized importance but remains a difficult objective to achieve for a multitude of factors including administrative and financial burdens on both the medical systems and the patients of host nations. Despite these limitations, longitudinal follow-up of patient care facilitated by a patient registry has a vital role in monitoring the quality of care provided and should be an integral part of all future global medical missions. [ABSTRACT FROM AUTHOR]