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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.

Additive manufacturing has enabled the fabrication of complex structures such as cellular structures. Although numerous design frameworks have been proposed for cellular structures, their effectiveness was limited owing to the use of B-rep-based representation. To address the limitations in previous research, this study proposes an implicit-based computer-aided design framework customized for additively manufactured functionally graded cellular structures (AM-FGCSs). The proposed design framework effectively aids in both single- and multiscale structural optimization for designing FGCSs. Moreover, implicit-based modeling afforded a reliable geometric representation that could efficiently assist computation tasks such as visualization, validation, and process planning for fabrication. In addition, two case studies were conducted to demonstrate the effectiveness of the proposed framework for designing FGCSs. The first case study on a three-point bending beam design problem proved the practicality of implicit-based representation in multiscale structural design. Meanwhile, the second case study validated the proficiency of the proposed framework in process planning for fabrication and engineering analysis, the two most vital computation tasks in designing cellular structures.

Biohydrogen production from biomass waste, not only addresses the energy demand in a renewable manner but also resolves the safe disposal issues associated with these biowastes. Also, scalable and low-cost techniques to enhance biohydrogen production have gained more attraction and are highly explored. In this research work, date-palm fruit wastes have been studied for their biohydrogen production potential using Enterobacter aerogenes by dark fermentation. Hydrogen yield and productivity were improved through the addition of iron oxide nanoparticles (Fe3O4 NPs) and its date seed activated carbon nanocomposites (Fe3O4/DSAC) to the fermentation media. Studies on discrete inclusions of these NPs showed that the appropriate dosage of NPs promoted, while higher dosages repressed the hydrogen production performance. Optimal dosage and fermentation time was observed as 150 mg/L and 24 h for both the additives. Fe3O4/DSAC nanocomposites showed better hydrogen production enhancement than Fe3O4 NPs. Maximum hydrogen yield of 238.7 mL/g was obtained for the 150 mg/L nanocomposites, which was 65.7% higher than that of the standalone Fe3O4 NPs and three folds higher than the yield of the control run without any NPs inclusion (78.4 mL/g). Metabolites analysis showed that the hydrogen evolution followed the ethanol-acetate pathway. Formation levels of longer chain propionate and butyrate co-metabolites were significantly low in the presence of Fe3O4/DSAC than Fe3O4. The carbon support in the nanocomposites acted as an adsorbent-buffer, which favored the medium pH in-addition to the stimulatory effects of Fe3O4 NPs. Cell growth and specific hydrogenase activity analysis were also performed to supplement the hydrogen production results. Gompertz and modified Logistic kinetic models were employed for kinetic modeling of experimental hydrogen production values. The Fe3O4/DSAC nanocomposites exhibited significant application potential for the production of biohydrogen from date fruit wastes.

In this paper, we propose a new class nonlinear hybrid controller (NHC) for swinging-up and stabilizing the (under-actuated) rotary inverted pendulum system. First, the swing-up controller, which drives the pendulum up towards the desired upright position, is designed based on the feedback linearization and energy control methods. Then, the modified super-twisting sliding mode control is proposed based on the new sliding surface to stabilize both the fully-actuated (the rotary arm) and under-actuated (the pendulum) state variables. In the proposed NHC, around the upright position, the stabilization controller is applied, and in different circumstances aside from the upright position, the swing-up controller is used. We show that with the proposed NHC: (i) in the swing-up stage, the pendulum is able to reach the desired upright position; and (ii) in the stabilization stage, the closed-loop rotary inverted pendulum is asymptotically stable. We demonstrate the effectiveness of the proposed NHC through extensive experiments. In particular, (i) the faster swing-up under the similar control effort is obtained, compared with the existing fuzzy logic swing-up controller; (ii) the better stabilization control performance for the convergence of the angular positions of the rotary arm and pendulum is attained and the chattering is alleviated, compared with the existing sliding mode stabilization controllers; (iii) the better stabilization control accuracy with the faster convergence time and lower peak overshoot is accomplished, compared with the existing Fuzzy-LQR controller; and (iv) the good robustness against sudden external disturbances is achieved.

A submerged photocatalytic membrane reactor (SPMR) was used with suspended and immobilized N–TiO2 under visible irradiation for diclofenac (DCF) removal from wastewater. The effects of initial N–TiO2 concentrations for the SPMR with suspended N–TiO2 were determined for batch processes. Hydrogen peroxide was also coupled with the photocatalytic process. In continuous conditions, a reverse osmosis (RO) membrane was combined with the SPMR for enhancing effluent quality. DCF removal by the SPMR with suspended and immobilized N–TiO2 at a low N–TiO2 dosage (0.5 g/L) was not much different between the two systems, but increased with higher N–TiO2 dosages for the reactor with suspended N–TiO2. Coupling H2O2 with the photocatalytic process under visible irradiation enhanced the DCF removal efficiency. In continuous conditions, DCF concentrations in the photoreactor increased during the reaction time, while those in the effluent (RO permeate) were steady for both systems and both processes. The permeate flux in the reactor with suspended N–TiO2 declined faster than in the reactor with the immobilized N–TiO2. Coupling H2O2 with the photocatalytic process yielded more resistant permeate flux rates. The cake layer formed on the microfiltration membrane of the SPMR with suspended N–TiO2 under visible irradiation was denser than others after completing the process.

Many technologies have been developed to treat the rubber effluent, but the quality of the treated effluent after the secondary treatment still does not meet the requirements for releasing it back to water bodies. This treated effluent becomes one of the most challenging problems for the Vietnamese rubber industry. Therefore, the present paper studied two applications as a potential solution for this issue. The first one is an advanced technology using membrane ultrafiltration, for a higher quality of the treated effluent that meets the disposal requirements. The second application is a direct reuse of the effluent for agricultural irrigation. For investigation of the effectiveness of the membrane filtration, a small-scale ultrafiltration apparatus with polyacrylonitrile membrane was used to conduct experiments on synthetic wastewater. The obtained results indicate that the membrane significantly reduced the COD concentration of the treated effluent to a level below the limit of 50 mg/L set by the Vietnamese Regulatory for discharge to water bodies. Kinetics of membrane ultrafiltration was also discussed. For the reuse of the treated effluent for irrigation, the effluent must have no negative impact on the groundwater. In order to investigate this aspect, a large-scale penetration test was conducted using a column filled with soil samples collected from rubber plantations in Binh Duong. The column penetration test results show that the irrigated effluent posed no harmful effect on groundwater. All COD, total nitrogen and phosphorous concentrations at a depth higher than groundwater were lower than the discharge limits for treated wastewater to water bodies.

Imidacloprid (IMI) is a widely used systemic pesticide that acts on the central nervous system of insects. In Vietnam, IMI was imported and manufactured in large quantities for agriculture activities. The presence of high IMI levels in IMI manufacturing wastewater is an environmental concern as this chemical is highly toxic and difficult to remove by traditional methods. In this study, IMI degradation by electro-Fenton process using Fe3O4–Mn3O4 nanoparticle composite catalyst was investigated over ranges of pH, current density, reaction duration, Mn3O4/Fe3O4 ratio, catalyst dosage, and initial IMI concentration. Three kinds of electrodes (graphite-, platinum-, and boron-doped diamond) were also employed to compare their application potential. With BDD electrodes, experiment results showed that at a current density of 15.0 mA/cm2, a Mn3O4/Fe3O4 ratio of 1:3 (w/w), and a catalyst dosage of 2.5 g/l, 60.0 mg/l IMI was reduced to 0.9 mg/l after 180 min reaction at pH 4.0. Outputs of TOC and BOD5 were 0.8 ± 0.5 mg/l and 2.6 ± 0.3 mg/l, respectively, which reflects that nearly all organic compounds were mineralized in the experiment. BDD electrode also shows the best performance. In addition, it was found that catalyst dosage should be increased with the growth of IMI concentration. The limitation for this correlation was at IMI concentration of 60.0 mg/l, which corresponded to a catalyst dosage of 2.5 g/l. Some other conditions provided good performance with economic potential also found for external desire.

This study reported comprehensive and systematic investigations on size and shape control of silver nanoplates (SNPs) through a simple synthesis route where individual effects of each reactant on surface plasmon resonance of silver nanoplates were thoroughly investigated. SNPs were successfully fabricated via chemical reduction of AgNO3 with the aid of TSC, PVP, NaBH4, and H2O2 as a primary capping agent, secondary capping agent, reducing agent, and oxidative etchant, respectively. The role and effects of each reagent on the size and uniformity of SNPs during the synthesis were deeply investigated. The results showed that both TSC and H2O2 played critical roles in the growth of SNPs. Sufficient amount of TSC in the solution ([TSC]:[Ag+] molar ratio ≤ 22.5) would favor the formation of small-sized SNPs, while large-sized SNPs could be obtained at an excessive concentration of TSC. In addition to TSC, H2O2 was also essential for the formation of SNPs whose size increased with the addition of H2O2. In contrast, PVP did not play a major role in the formation of SNPs. It functioned as a secondary capping agent to prevent the formation of larger SNPs and facilitated the production of small-sized SNPs with equal uniformity. This role of PVP was particularly significant at the low level of TSC. The results were crucial for deeply understanding the individual effects of each reagent on the size and uniformity of SNPs so as to control the size and shape of SNPs for better surface-enhanced Raman scattering (SERS) signals of 4-mercapto benzoic acid (4-MBA).

Despite the burgeoning interests in the environmental strategy, there is a limited understanding of how human resource slack drives sustainable innovation and environmental performance. This paper contributes to filling this gap by examining the effect of human resource slack on sustainable innovation and its impact on environmental performance. Besides, this paper investigates the contingent effects of intangible resource advantage on this relationship. The hypotheses are tested using data from 301 small and medium‐sized enterprises in Ghana. The results suggest that human resource slack positively relates to sustainable innovation and this relationship is moderated by intangible resource advantage. Also, we find that sustainable innovation mediates the relationship between human resource slack and environmental performance. The insights from our paper provide a nuanced understanding of the relationships among human resource lack, sustainable innovation, and environmental performance. Implications for theory and practices are discussed.

Welding in the world (2020). doi:10.1007/s40194-020-00913-3, Published by Springer, Heidelberg

Blast furnace slag is a waste of metallurgical industry which can be used in production technology of concretes and mortars. The expedient use of blast furnace slag as a component for new building materials will improve the environmental situation and increase the economic efficiency of production. The authors reaserch blast furnace slag processing technology of factories "Hoa Phat" (Vietnam) and "Thai Nguyen" (Vietnam) to produce mineral additives. As a result of the conducted researches the chemical and mineralogical composition of slags are received, their physical and mechanical characteristics are considered and defined: specific surface area, density, water demand, and others. According to standard of Vietnam and Russia, slag activity index is calculated when considering the possibility of using blast furnace slags to replace part of the binder. The relationship between the strength of the cement-sand mortar and density affected by the binder are reveald (where; binder = Portland cement + Granulated blast furnace slag). Comparison chart of slag activity index IR (%) has been shown. The paper uses the Vietnamese standard TCVN 11586: 2016 to analyze the possibility of using blast furnace slag (Vietnam) in the technology of concrete and mortar construction.

To the north of Hanoi, about a day's drive by car, lies Ha Giang Province, the northernmost region of Vietnam. Ha Giang is remote from the hustle and bustle of daily life, and beyond its eponymous provincial capital towards the border with China, mountains rise quickly to Quan Ba, ‘Heaven's Gate’. The mountains form an uneven landscape of steep‐sided karst rising from deep river‐cut gorges and form a formidable barrier on the northern frontier of Vietnam. Beyond ‘Heaven's Gate’ lies the little travelled region of Dong Van, with its majestic mountains of Palaeozoic strata rising precipitously to the sky. Here, a century ago, the French geologists Henri Mansuy and Jacques Deprat documented early finds of fossils from lower Palaeozoic strata on the border with China.

Wastewater from instant coffee production has high organic content. The non-biodegradable compounds of the organic portion, such as caffeine, trigonelline, and diterpene, are difficult to be removed by conventional processes. Electro-Fenton (EF) with particulate catalyst has been found to be a promising method to treat such compounds. Comparing with homogenous Fenton process, EF uses fewer chemicals and generated less sludge. The catalysts can be easily recovered by magnets if they have magnetic properties. In this study, 30–60 nm composite Fe3O4–Mn3O4 nanoparticles were prepared and used as EF catalyst for the treatment of non-biodegradable organic matters in biologically pre-treated wastewater from instant coffee production. These particles were found to contain Fe3O4, γ-Fe2O3, and Mn3O4, which were effective metal sources for Fenton reactions. The correlations between three important operating parameters (i.e., pH, catalyst concentration, and current density) and the treatment efficiency of the non-biodegradable compounds were elucidated by response surface method (Box–Behnken design) via Modde software. An optimal condition was found at a pH of 3.8, a Fe3O4–Mn3O4 concentration of 0.5 g/L, and a current density of 19.6 mA/cm2. After 60 min of treatment at this condition, the highest removal efficiencies of chemical oxygen demand (COD), color, and total organic carbon in the wastewater were 88%, 98%, and 93%, respectively. With this degree of treatment, the COD and color in treated wastewater met the highest treatment level of Vietnam National Technical Regulation on Industrial Wastewater (QCVN 40:2011, column A, 75 mgO2/L for COD, and 50 Pt–Co for color).

Stauntonia hexaphylla (Lardizabalaceae) is an important medicinal plant in Korea, Japan, and China. Its leaves are used to treat many diseases because of their analgesic, sedative, and diuretic eff...

Purpose The purpose of this paper is to study the roles of dual personal values (individualistic and collectivistic) and consumer attitudes toward dual purchase consequences (individual and environmental) as the precursors of a commitment to green consumption. Furthermore, the variance within the studied relationships is explored across the segments of the selected consumer sample. Design/methodology/approach Partial least squares and finite mixture–partial least squares path modeling approaches are employed to examine the studied relationships and check for heterogeneity, respectively, among the sample of 406 Vietnamese consumers. Findings The results indicate that individualistic values positively and negatively affect attitudes toward purchase consequences at the individual and environmental levels, respectively, while collectivistic values have only a positive impact on attitudes at the environment level. Compared to the individual level, attitudes toward environmental purchase consequences propagate a fuller commitment to green consumption. Collectivistic, but not individualistic, consumers are a suitable target segment for green business. Consumers within the selected sample exhibit different green behavioral patterns. Originality/value This research provides valuable insights into the under-researched aspect of green consumption commitment based on an extended value–attitude–behavior model. Previously unobserved heterogeneity is revealed and green consumption tendency segments are identified.

The world is constantly seeking new sources of energy to replace the use of coal and fossil fuels to generate electricity. And a strong source of energy from the ocean is one of the hopes of scientists around the world. Ocean energy is an endless renewable energy source for making electricity used for the world. Marine technology was once considered too expensive to be a viable source of alternative clean energy, especially compared to already developed products such as wind and solar. However, with the increased price of oil and the issues of global warming and national security, U.S. coastal sites are looking to add ocean energy to their renewable energy portfolios. This paper gives an overview of ocean energy technologies, focusing on two different types: wave, tidal. It outlines the operating principles, the status, and the efficiency and cost of generating energy associated with each technology.

In this report, we describe the first discovery of two living ostracods from the Japanese archipelago, Sinocytheropteron ignobile and Sinocytheridea impressa, which are typically continental faunal elements from China, during our research on the distribution of ostracod assemblages in the Ariake and Yatsushiro Seas in southwest Japan. The (palaeo-) biogeographical data from recent and fossil records indicate that S. ignobile and S. impressa migrated through land bridges during past decreases in sea levels. We also discovered Xestoleberis ryukyuensis, which has been reported from the Ryukyu Islands; its discovery in our study area indicates the current northernmost distribution of the species and suggests that it migrated from the Ryukyu Islands to the study area using the Tsushima Warm Current, a branch of the main Kuroshio Current. This evidence suggests that the migration of shallow-marine ostracods between the continents and their adjacent islands affect not only global oceanic current but also global decreases in sea levels and the (palaeo-) geography of adjacent seas. Thus, ostracods living within the continental coasts provide powerful evidence for reconstructing the connection between the continent and its adjacent islands.

In this study, the Fe-containing tailings (Fe-TO) ore was reutilized and enriched with FeCl3 as a heterogeneous catalyst for the Fenton process to degrade the organic dyes from aqueous solution. The determinants of the heterogeneous catalytic Fenton system which included iron modification ratio, solution pH, catalyst dosage, H2O2 dosage and initial concentration of organic dyes were systematically investigated. The modification ratio of 15% (w/w of iron), pH of 3, MFe-TO15 dosage of 0.5 g L−1 and H2O2 dosage of 840 mg L−1 were chosen as the best operational conditions for Fenton oxidation of organic dyes. The decolorization efficiency of both MB and RhB by MFe-TO15/H2O2 was higher than that of Fe-TO/H2O2 by about two times. The kinetic study showed the degradation of organic dyes well fitted the pseudo-first-order kinetic model with apparent constant rate values (Kd) following the same sequence as the degradation efficiency of organic dyes. The degradation mechanism of dyes could be attributed to adsorption due to the good-development in textural properties of the iron modified catalyst (MFe-TO) with an increase in BET surface area, pore volume and pore diameter of, respectively, 2, 5 and 5 times and leaching iron through homogeneous Fenton reaction. However, the oxidation process occurring on the MFe-TO15's surface by heterogeneous Fenton reaction which enhanced decomposition of H2O2 for continuous generation of hydroxyl radicals was the main mechanism. The key role of *OH radical in oxidation of organic dyes was further ascertained by the remarkable drop in the decolorization of both organic dyes when the various radical-scavengers, including tert-butanol and chloride were supplemented into Fenton systems. A good stability of the catalyst was obtained through leaching test with low leaching iron ratio. The applied modified catalyst remained stable through three consecutive runs. From these findings, it can be concluded that the modified material can be applied as a feasible, inexpensive and highly effective catalyst for removal of persistent organic compounds from wastewater.

Widespread seafloor methane venting has been reported in many regions of the world oceans in the past decade. Identifying and quantifying where and how much methane is being released into the ocean remains a major challenge and a critical gap in assessing the global carbon budget and predicting future climate [C. Ruppel, J. D. Kessler. Rev. Geophys. 55, 126–168 (2017)]. Methane hydrate ([Formula: see text]) is an ice-like solid that forms from methane–water mixture under elevated-pressure and low-temperature conditions typical of the deep marine settings ([Formula: see text] 600-m depth), often referred to as the hydrate stability zone (HSZ). Wide-ranging field evidence indicates that methane seepage often coexists with hydrate-bearing sediments within the HSZ, suggesting that hydrate formation may play an important role during the gas-migration process. At a depth that is too shallow for hydrate formation, existing theories suggest that gas migration occurs via capillary invasion and/or initiation and propagation of fractures (Fig. 1). Within the HSZ, however, a theoretical mechanism that addresses the way in which hydrate formation participates in the gas-percolation process is missing. Here, we study, experimentally and computationally, the mechanics of gas percolation under hydrate-forming conditions. We uncover a phenomenon—crustal fingering—and demonstrate how it may control methane-gas migration in ocean sediments within the HSZ.

Bacterial tRNA-guanine transglycosylase (Tgt) is involved in the biosynthesis of the modified tRNA nucleoside queuosine present in the anticodon wobble position of tRNAs specific for aspartate, asparagine, histidine and tyrosine. Inactivation of thetgtgene leads to decreased pathogenicity ofShigellabacteria. Therefore, Tgt constitutes a putative target for Shigellosis drug therapy. Since only active as homodimer, interference with dimer-interface formation may, in addition to active-site inhibition, provide further means to disable this protein. A cluster of four aromatic residues seems important to stabilize the homodimer. We mutated residues of this aromatic cluster and analyzed each exchange with respect to dimer and thermal stability or enzyme activity applying native mass spectrometry, thermal shift assay, enzyme kinetics, and X-ray crystallography. Our structural studies indicate strong influence of pH on homodimer stability. Obviously, protonation of a histidine within the aromatic cluster promotes the collapse of an essential structural motif within the dimer interface at slightly acidic pH.TOC GraphicFor table of contents use only.

We will investigate numerically a seesaw model with $A_4$ flavor symmetry to find allowed regions satisfying the current experimental neutrino oscillation data, then use them to predict physical consequences. Namely, the lightest active neutrino mass has order of $\mathcal{O}(10^{-2})$ eV. The effective neutrino mass $|\langle m\rangle|$ associated with neutrinoless double beta decay is in the range of $[0.002 \;\mathrm{eV},0.038\;\mathrm{eV}]$ and $[0.048\;\mathrm{eV},0.058\;\mathrm{eV}]$ corresponding to the normal and the inverted hierarchy schemes. Other relations among relevant physical quantities are shown, so that they can be determined if some of them are confirmed experimentally. The recent data of the baryon asymmetry of the Universe ($\eta_B$) can be explained via leptogenesis caused by the effect of the renormalization group evolution on the Dirac Yukawa couplings, provided the right handed neutrino mass scale $M_0$ is ranging from $\mathcal{O}(10^8)$ GeV to $\mathcal{O}(10^{12})$ GeV for $\tan\beta =3$. This allowed $M_0$ range distinguishes with the scale of $\mathcal{O}(10^{13})$ GeV concerned by other effects that also generate the consistent $\eta_B$ from leptogenesis. The branching ratio of the decay $ \mu \rightarrow\,e\gamma$ may reach the future experimental sensitivity in the very light values of $M_0$. Hence, it will be inconsistent with the $M_0$ range predicted from the $\eta_B$ data whenever this decay is detected experimentally., Comment: The accepted version to PTEP

Recovering the scene depth from a single image is an ill-posed problem that requires additional priors, often referred to as monocular depth cues, to disambiguate different 3D interpretations. In recent works, those priors have been learned in an end-to-end manner from large datasets by using deep neural networks. In this paper, we propose guiding depth estimation to favor planar structures that are ubiquitous especially in indoor environments. This is achieved by incorporating a non-local coplanarity constraint to the network with a novel attention mechanism called depth-attention volume (DAV). Experiments on two popular indoor datasets, namely NYU-Depth-v2 and ScanNet, show that our method achieves state-of-the-art depth estimation results while using only a fraction of the number of parameters needed by the competing methods. Code is available at: https://github.com/HuynhLam/DAV.

Welding in the world 64(11), 1939–1946 (2020). doi:10.1007/s40194-020-00973-5, Published by Springer, Berlin

This study was conducted to determine the effects of different storage temperatures and storage durations on postharvest diseases of dragon fruit grown in the Mekong delta region. Dragon fruit of uniform maturity and without defects were collected from two growers in Long An and Tien Giang provinces and stored at 0, 5 and 10°C for 21 and 26 days followed by storage at 20°C for 3 days to simulate shelf life in the market. Other fruit were harvested and held at 20°C for 7 and 12 days as a non-stored control. The proportion of fruit with rots and changes in bract appearance were recorded and analyzed. The results indicated that fruit stored at 0 and 10°C (for both 21-26 days), and the control fruit held at 20°C for 7 and 12 days sustained the most damage. The most common disorders were rots and wilting and colour change (yellowing) of the bracts. Fruits stored for 21 and 26 days at 6°C remained fresh in appearance and had significantly fewer rots. The pathogenicity of fungi isolated from the rots was confirmed by re-inoculation of healthy fruit and the pathogens identified by conventional and molecular methods. The main fungi associated with spoiled fruit were: Alternaria alternata, Aspergillus sp., Bipolaris cactivora, Cladosporium sp., Colletotrichum gloeosporioides, Colletotrichum truncatum, Fusarium andiyazi, Fusarium dimerum, Fusarium equiseti, Geotrichum candidum, Mucor sp., Neoscytalidium dimidiatum, Phomopsis longicolla, and Rhizopus stolonifer.

Graphene intrinsically hosts charge-carriers with ultrahigh mobility and possesses a high quantum capacitance, which are attractive attributes for nanoelectronic applications requiring graphene-on-substrate base architecture. Most of the current techniques for graphene production rely on the growth on metal catalyst surfaces, followed by a contamination-prone transfer process to put graphene on a desired dielectric substrate. Therefore, a direct graphene deposition process on dielectric surfaces is crucial to avoid polymer-adsorption-related contamination from the transfer process. Here, we present a chemical-diffusion mechanism of a process for transfer-free growth of graphene on silicon-based gate-dielectric substrates via low-pressure chemical vapor deposition. The process relies on the diffusion of catalytically produced carbon radicals through polycrystalline copper (Cu) grain boundaries and their crystallization at the interface of Cu and underneath silicon-based gate-dielectric substrates. The graphene produced exhibits low-defect multilayer domains ( L

At present, oil spills are a potential threat to coastal states. In many sea areas of the sea, the phenomenon of "black tide" is common. There are many causes for this situation such as collisions, accidents of water transport vehicles (especially oil tankers), oilrig incident, oil spill incident due to geological changes, waste oil burglary on the sea. For Vietnam, about 200 million tons of oil are transported each year through the sea. In the process of transporting and exploiting offshore, there may be incidents leading to oil spills into the sea, polluting the marine environment. According to statistics, in the past 20 years, about 10 oil spills have been recorded annually, especially in 2012, there were 12 cases affecting the estuarine and coastal environment of Vietnam and coastal ecosystems as well as coastal resorts. This article presents a report on oil spills occurring in Vietnam and policies of the Vietnamese government to respond to oil spills.

Accumulation of fine grained sediment and natural regeneration of mangrove species are normally prioritized to control erosion on mangrove dominated muddy coasts. Current solutions to manage eroded mangrove dominated muddy coasts have been not as cost-effective as expected. Entrapping microsites, although mainly used for restoring eroded terrestrial resources, were first tested for restoring an eroded mangrove dominated muddy coast of Vam Ray, Hon Dat, Kien Giang, Vietnam. Entrapping microsites, constructed with a 50 cm layer of discarded Melaleuca small sticks that were overlain on the surface of the site, accumulated a high level of fine grained sediment and promoted robust natural regeneration or regrowth of local mangrove species after approximately two years. The effectiveness and efficiency of the Vam Ray Melaleuca entrapping microsites provide a good basis on which further research and ground works can proceed.

Due to the scarcity of the resource oil but also to increasing environmental awareness the market of biopolymers show a continuous growth. Biopolymers have different properties compared to conventional polymers which could lead to different processing requirements for the laser transmission welding process. In order to investigate the suitability of the process and to elaborate the differences between conventional polymers and biopolymers, three biopolymers [PLA, Bio-PE, and Bio-PET] are selected and on these laser welding tests are performed. An adapted diode-laser-beam source is used for the welding process. The created samples are analyzed and evaluated by thin sections and tensile tests.

Despite repeated efforts to transplant mangroves to stop coastal erosion, the Brebes coasts were severely eroded between 2010 and 2013. Effective coastal erosion control in Brebes is not possible if the current situation is not adequately addressed and problems not properly identified. This study applied participatory action research methods for critically reviewing current mangrove transplantation projects in Brebes Regency, Indonesia. Mangrove transplantation has had limited success in restoring Brebes eroding coasts. Inefficient nursery operation, the wrong choice of mangrove species, improper transplantation techniques, poor coastal protection, and inadequate ongoing monitoring and evaluation significantly contributed to the limited success. Inadequate monitoring and evaluation meant that few lessons were learnt and the same mistakes continued to be made. Recommendations for production of mangrove seedlings, mangrove transplantation techniques, and monitoring and evaluation are provided to ensure effective mangrove transplantation in the future in Brebes Regency, Indonesia.

While current coastal erosion solutions have had limited success in controlling coastal erosion, the gradual expansion of mangrove areas was effective in stabilizing an actively eroded mangrove dominated muddy coast in Vam Ray, Kien Giang, Vietnam for a short time period. The gradual expansion method was developed as a result of local comprehensive involvement and capacity, and the integration of different knowledge systems. However, the method was not sufficiently reported. Local involvement and capacity were not adequately emphasized during the reporting process. Insufficient reporting caused the failure in replicating the method elsewhere in Kien Giang. Inadequate emphasis of local involvement and capacity probably breached moral rights for the Vam Ray community. This manuscript documented the gradual expansion method using different sources of data and information and inputs from the key Vam Ray community members. The gradual expansion method involved closure of current mangrove gaps by transplanting mangroves protected by appropriate fences as the first stage, and gradual expansion of the mangrove belt seawards in the second stage. The method has a potential replication elsewhere in Vietnam and in Southeast Asia.

We propose an overloading control system with a novel method to estimate vehicle weight using the sensor data from a smartphone mounted on the vehicle. The conventional method based on fixed weigh stations has limited coverage, and is expensive to install and maintain. Our proposed system overcomes these limitations by using smartphones, which are portable and cheaper. A multiple linear regression model is created using vertical acceleration statistical features and loading status classification as explanatory variables to estimate the vehicle’s weight. A pilot experiment estimating a trolley’s weight was followed by an experiment estimating an actual vehicle’s weight to verify the feasibility of using our method. We achieved average error of 593 kg, which accounted for 5.89% of the true average vehicle’s weight.

Binding graphene with auxiliary nanoparticles for plasmonics, photovoltaics, and/or optoelectronics, while retaining the trigonal-planar bonding of sp2 hybridized carbons to maintain its carrier-mobility, has remained a challenge. The conventional nanoparticle-incorporation route for graphene is to create nucleation/attachment sites via “carbon-centered” covalent functionalization, which changes the local hybridization of carbon atoms from trigonal-planar sp2 to tetrahedral sp3. This disrupts the lattice planarity of graphene, thus dramatically deteriorating its mobility and innate superior properties. Here, we show large-area, vapor-phase, “ring-centered” hexahapto (η6) functionalization of graphene to create nucleation-sites for silver nanoparticles (AgNPs) without disrupting its sp2 character. This is achieved by the grafting of chromium tricarbonyl [Cr(CO)3] with all six carbon atoms (sigma-bonding) in the benzenoid ring on graphene to form an (η6-graphene)Cr(CO)3 complex. This nondestructive function...

With the layer-dependent tunability of their optical band gap in the near-infrared (IR ) to visible spectrum, transition metal dichalcogenides (TMDs), including molybdenum disulfide (MoS2) and tungsten disulfide (WS2), exhibit strong light-matter interactions, making them suitable as absorber layers for optoelectronic devices. Currently, the WS2-based solar cells are fabricated via micromechanical/chemical exfoliation or transfer of two-dimensional (2-D) WS2 layers onto conventional three-dimensional (3-D) bulk semiconductors, which poses a challenge for large-scale integrations and consequent device performances.

A management policy adopted by the Kien Giang Province, Vietnam, is to allocate mangroves areas using contracts with local community members who are dependent on mangrove resources for both mangrove protection and livelihood improvement. However, community members have not made the best use of the allocated areas, and mangroves have not been well protected. The policy is due to be revised in late 2016, as is legally required. This study used mixed methods to review the policy and its implementation with respect to mangrove protection requirements and use of mangroves for livelihood improvement and to provide recommendations for sustainable mangrove management in Kien Giang. The policy and its implementation is demonstrated to be a constraint to achieving its goal. Limited understanding of the policy of contractees resulted in ineffective and inefficient aquaculture and mangrove protection in almost all areas. Permitted thinning and selective harvests led to the creation of substantial gaps and disconnections in the established mangroves, making the entire coastline vulnerable to coastal erosion. Improper technical guidance on the configuration of mangrove allocations, and mangrove protection and transplantation methods resulted in the mangrove protected areas being fragmented and vulnerable to erosion. Permitted thinning and selective harvest practices should be reviewed to ensure adequate resilience and protection of mangrove areas, especially on critically eroding areas. Proper law enforcement should be put in place to ensure contracts are adequately implemented. Allocation and/or transferal of areas less than 1 ha must be discontinued in the future to avoid further defragmentation and degradation. Technical guidance on configuring allocated mangrove areas should be established and incorporated into the updated policy that would help improve the effectiveness of the policy, and address problems relating to strengthening resilience and protection of mangrove areas in Kien Giang Province, Vietnam. Similar programs using mangrove area allocation to individuals and households in response to mangrove area loss exist elsewhere in the Mekong delta. Understanding the reasons for the very limited success of the Kien Giang program and local co-investigation in drawing lessons learnt can help guide other similar programs elsewhere in the Mekong Delta region.

Mangrove dominated muddy coasts (MDMCs) throughout the world have been made vulnerable to erosion by human induced and natural factors. Meanwhile, their management has not been clearly identified in the literature. This study uses a comprehensive literature review to describe strategies, specifically designed to manage MDMCs for effectiveness, and provides recommendations for sustainable management of these coasts. Only a small percentage of previous studies deals with real-world management of MDMCs. Two approaches that are specifically designed to manage MDMCs are science-based approaches and local knowledge-based approaches. Both approaches, each having advantages, have had limited success in effectively managing MDMCs, with a low level of local involvement, and a minimal integration of the different knowledge systems. MDMCs and their management should be distinguished from other types of coasts to avoid possible confusion in the literature. Mechanisms are needed for integrating different knowledge systems for effectively managing MDMCs. These mechanisms should promote a high level of integration of local and scientific knowledge, local ownership, and sustainability.

This article presents a rather well-preserved radiolarian fauna recovered from black siliceous mudstone occurring in the Ky Cung River section 02 (KC02) of the Bac Thuy Formation, Lang Son Province, northeastern Vietnam. The KC02 section has been regionally correlated on the basis of the first appearance of the diagnostic Spathian ammonoid Tirolites . The ammonoid assemblage associated with radiolarians indicates that the black mudstone sample is early Spathian in age (Late Olenekian). The radiolarian fauna is characterized by a very low diversity of entactinarians of the family Hindeosphaeridae and of to another unidentified family, and by the absence of nassellarians. Here we describe two new species of entactinarians, Parasepsagon primitivus nov. sp. and Eptingium ? reticulatum nov. sp. The composition of the fauna suggests that the beginning of diversification of Mesozoic-type radiolarians occurred at the beginning of the Spathian on the eastern margin of the tropical Tethys.

In this work, gold nanostar (AuNPs) and gold nanodendrites were synthesized by one-pot and environmentally friendly approach in the presence of gelatin. Influence of gelatin concentrations and reaction conditions on the growth of branched (AuNPs) were investigated further. Interestingly, the conversion of morphology between dendritic and branched nanostructure can be attained by changing the pH value of gelatin solution. The role of gelatin as a protecting agent through the electrostatic and steric interaction was also revealed. Branched nanoparticles were characterized by surface plasmon resonance spectroscopy (SPR), transmission electron microscopy (TEM), XRD, dynamic light scattering (DLS) and zeta-potential. The chemical interaction of gelatin with branched gold nanoparticles was analyzed by Fourier transform infrared spectroscopy (FT-IT) technique. Ultraviolet visible spectroscopy results indicated the formation of branched gold nanoparticles with the maximum surface plasmon resonance peak at 575&ndash, 702 nm. The structure of both nanodendrites and nanostars were determined by TEM. The crystal sizes of nano-star ranged from 42 to 55 nm and the nanodendrites sizes were about 75&ndash, 112 nm. Based on the characterizations, a growth mechanism could be proposed to explain morphology evolutions of branched AuNPs. Moreover, the branched AuNPs is high viability at 100 &mu, g/mL concentration when performed by the SRB assay with human foreskin fibroblast cells.

The problem of predicting a novel view of the scene using an arbitrary number of observations is a challenging problem for computers as well as for humans. This paper introduces the Generative Adversarial Query Network (GAQN), a general learning framework for novel view synthesis that combines Generative Query Network (GQN) and Generative Adversarial Networks (GANs). The conventional GQN encodes input views into a latent representation that is used to generate a new view through a recurrent variational decoder. The proposed GAQN builds on this work by adding two novel aspects: First, we extend the current GQN architecture with an adversarial loss function for improving the visual quality and convergence speed. Second, we introduce a feature-matching loss function for stabilizing the training procedure. The experiments demonstrate that GAQN is able to produce high-quality results and faster convergence compared to the conventional approach., 12 pages, 4 figures, accepted for presentation at the Scandinavian Conference on Image Analysis 2019

Detection and classification of road markings are a prerequisite for operating autonomous vehicles. Although most studies have focused on the detection of road lane markings, the detection and classification of other road markings, such as arrows and bike markings, have not received much attention. Therefore, we propose a detection and classification method for various types of arrow markings and bike markings on the road in various complex environments using a one-stage deep convolutional neural network (CNN), called RetinaNet. We tested the proposed method in complex road scenarios with three open datasets captured by visible light camera sensors, namely the Malaga urban dataset, the Cambridge dataset, and the Daimler dataset on both a desktop computer and an NVIDIA Jetson TX2 embedded system. Experimental results obtained using the three open databases showed that the proposed RetinaNet-based method outperformed other methods for detection and classification of road markings in terms of both accuracy and processing time.

International audience; ABSTRACTWe present a procedure dedicated to the calibration of a scanning thermal microscopy probe operated in an active mode and a modulatedregime especially for the measurement of solid material thermal conductivities. The probe used is a microthermocouple wire mounted on aquartz tuning fork. Measurements on reference samples are performed successively in vacuum and ambient air conditions revealing a cleardifference in the dependence of the thermal interaction between the probe and the sample on the sample properties. Analytical modelingbased on the resolution of the heat equation in the wire probe and a description of the thermal interaction using a network of thermalconductances are used to fit experimental data and analyze this difference. We have experimentally verified that the effective thermal contactradius of the probe tip depends on the sample thermal conductivity in ambient conditions, whereas it remains constant in vacuum. We havedefined the measurement range of the technique based on the decrease in the probe sensitivity at high thermal conductivities. Consideringthe experimental noise of our electrical device, it is shown that the maximum measurable value of thermal conductivity is near 23Wm−1 K−1in vacuum and 37 W m−1 K−1 in ambient air conditions. Moreover, the lowest uncertainties are obtained for thermal conductivities below5Wm−1 K−1 typically.

International audience; We demonstrate the functionality of a new active thermal microchip dedicated to the temperature calibration of scanning thermal microscopy (SThM) probes. The silicon micromachined device consists in a suspended thin dielectric membrane in which a heating resistor with a circular area of 50 lm in diameter was embedded. A circular calibration target of 10 lm in diameter was patterned at the center and on top of the membrane on which the SThM probe can land. This target is a resistive temperature detector (RTD) that measures the surface temperature of the sample at the level of the contact area. This allows evaluating the ability of any SThM probe to measure a surface temperature in ambient air conditions. Furthermore, by looking at the thermal balance of the device, the heat dissipated through the probe and the different thermal resistances involved at the contact can be estimated. A comparison of the results obtained for two different SThM probes, microthermocouples and probes with a fluorescent particle is presented to validate the functionality of the micromachined device. Based on experiments and simulations, an analysis of the behavior of probes allows pointing out their performances and limits depending on the sample characteristics whose role is always preponderant. Finally, we also show that a smaller area of the temperature sensor would be required to assess the local disturbance at the contact point.

We report star-shaped silver@gold (Ag@Au) nanoparticles (NPs) in gelatin suspensions for the purpose of enhancing the stability of Ag@Au NPs. In this case, Ag NPs were designed as nucleating agents, whereas gelatin was used as a protecting agent for Au development. Especially, variable gelatin concentrations were also prepared to explore its ability to increase the stability of Ag@Au NPs. The obtained samples were then characterized by UV-visible spectroscopy, transmission electron spectroscopy (TEM), X-ray diffraction, and Fourier transform infrared spectroscopy. The maximum absorption wavelength of all samples (566–580 nm) indicated that branched Ag@Au@gelatin NPs were successfully synthesized. In addition, our TEM results revealed that the size of branched Ag@Au@gelatin NPs was found to be between 20 and 45 nm as influenced by the component ratio and the pH value. These results can provide valuable insights into the improvement of Ag@Au NP stability in the presence of gelatin.

In this report, star-shaped silver@gold (Ag@Au) nanoparticles were synthesized in collagen (Coll) suspensions by a seeding growth approach. The silver nanoparticles were used as seeds for Au development. Coll was used as a protecting agent and the effect of its concentration on stability was also examined. Obtained nanoparticles were then characterized by UV-Vis, TEM, XRD and FTIR. The result was confirmed by the maximum surface plasmon resonance peak at 566-580 nm for each sample indicating the formation of branched Ag@Au@Coll NPs. The average diameters of the branched Ag@Au@Coll NPs were revealed to be 30-50 nm depending on the corresponding component ratio and the pH value. It is interesting to note that the concentration of Coll plays a critical role in the stability of the star-shaped gold nanoparticles. The results offer an understanding of the handling of the electronic and the silver@gold based nanoparticles stability properties.

It is common for environmental restoration projects to be reviewed by the administering organizations but it is much less common for the communities that the projects are meant to serve to detail their experiences and perceptions of the outcomes. We evaluate an internationally funded mangrove restoration project and reflect upon the lessons learned in regard to the project strategies and interventions, particularly from the perspective of the local community. The Vam Ray coast, Kien Giang Province, Vietnam, was seriously eroded by 2008. In May 2009, a demonstration project was established which achieved a high survival rate of transplanted mangroves and sea mud accumulation. This study used participatory action research methods (literature review, semi-structured interviews, field visits, and peer debriefing) to evaluate the project outcomes. Despite the project being generally very successful, its implementation and results were inadequately documented by agencies involved due in large part to insufficient local involvement during the reporting process, even though the local community was fully involved in the project planning and implementation. Inadequate documentation has led to mistakes being made when attempts have been made to replicate the project elsewhere, and incomplete findings have been incorporated into mangrove management plans at the provincial and regional levels. Using the community knowledge from the time of the project implementation and since, we detail the successes and problems encountered to provide more complete reporting, to assist transferability of the methods to other eroding muddy coasts in Vietnam and potentially elsewhere.

This progress of industry revolution, which involves reutilizing waste materials and simplifying complex procedures of analysis through artificial intelligent (AI), are the current interest in automated industries. There are two main objectives, firstly, the use of waste molasses from sugar mills as a cultivation medium for microalgae and nutrients extraction. The biomass in 15% of the molasses medium without carbon dioxide aeration during cultivation obtained the highest dry cell weight at 1206.43 mg/L. Protein content in the biomass of 10% molasses cultivation medium is 20.60%, which is higher compared to commercial mediums. Secondly, the exploitation of the deep colouration properties of molasses-cultivated microalgae, a novel photo-to-property estimation was performed by k-Nearest Neighbour (k-NN) algorithm through RGB model pixel raster in the images to rapidly determine the biomass concentration, nitrogen concentration and pH without use of tedious analytical processes. The k-value at 4 was studied in normalized Root-Mean-Square-Error (RMSE) for biomass concentration at 0.10, nitrate at 0.11, and pH at 0.02 for a sequence of days.

Current practice for C-phycocyanin (CPC) extraction from fresh biomass is greatly perishable, so dried biomass is preferable for longer storage life and saving spaces for small scale industries. However, the resistance of dried biomass towards cell disruption is higher compared to fresh biomass. Therefore, this work aims to develop an effective technique for the extraction of CPC from dried Spirulina sp. This study addresses the effect of sonoprocessing-assisted with liquid biphasic flotation (LBF) for the extraction and purification of CPC and allophycocyanin (APC). The application of ultrasound was optimized by various parameters such as amplitude (20 to 30%), sonication time in pulse mode (5 to 25 s), resting time in pulse mode (5 to 25 s) and the total time of sonication (3 to 12 min). While for the liquid biphasic flotation, the studied parameters were air flowrate (75 to 175 cc/min), a volume ratio of both phases (1:0.5 to 1:1.5), flotation time (3 to 12 min), and weight of biomass (0.1 to 0.6 g). Results of both CPC and APC were determined using the optimized conditions and subjected to SDS-PAGE analysis. Total purification factor of 5.23 and recovery of 95.10% were obtained using 30% amplitude, 5 s ON/5s OFF (pulse mode), 10 min sonication, volume ratio 1:1, 100 cc/min air flowrate, 7 min flotation time, and 0.45 g biomass. This study proves that the suggested method enhances efficiency in the recovery of CPC and demonstrates the synergistic effect of sonoprocessing with LBF in extracting CPC and other biomolecules from microalgae.

We present constant-flow experiments of high-pressure CO2-saturated fluid through fracture channels in Portland cement with three different fracture geometries and with three different flow rates. The experiments were conducted in etched cement wafers within a microfluidics device. The evolution of pH was observed optically using phenolphthalein dye and changes in channel volume due to dissolution and/or precipitation were characterized with profilometry and scanning electron microscopy. Abundant precipitation for all three geometries was observed in the low flow-rate experiments, while only dissolution was observed in the high-flow rate experiments. The results bracket self-sealing versus self-opening behavior. The observed functional relationship among flow rate, fracture geometry and aperture in relation to self-sealing is consistent with a diverse set of experiments in the literature conducted under widely varying conditions and with behavior predicted in recent numerical models (Brunet et al., 2016; Cao et al., 2015; Guthrie et al., 2018; Iyer et al., 2017). The results confirm that self-sealing is a quantifiable behavior in ordinary Portland cement systems that is favored at low flow rates and in small-aperture or small hydraulic diameter fracture systems with clear limits imposed by dissolution-dominated conditions of high flow rates.

The field of application of multilayer polymer films ranges from the packaging of food and other goods to medical technology and the encapsulation of organic electronics. The layer structure of the polymer films is adapted to the respective areas of application. Usually, polymer film systems contain several individual layers. A trend toward more flexible production and batch sizes down to one can be identified in all the above-mentioned areas of application. This requires new production processes. Laser transmission welding with adapted laser beam sources represents a promising approach for this. It is characterized by a contactless and a locally limited energy position. A very high degree of format flexibility is also possible, thanks to a purely numerical adjustment of the welding contour. In many applications, it is desired to keep the polymer film as it is available on the market. If two multilayer polymer films should be welded with laser radiation in an overlapping arrangement, sufficient absorption of the laser radiation in the material is required. Each individual polymer layer has wavelength-dependent material-specific optical properties. Due to the vibrations of polymer chains, polymers have absorption peaks in the near infrared range. If a suitable laser beam source is now used for the welding process, the energy can be deposited directly in the material without modifying it beforehand. The energy input should be the highest at the point of contact or in the sealing layers of the two polymer films so that it is locally heated and melted. The surrounding film layers are also thermally influenced by heat conduction processes. In addition, the optical properties of the other layers influence the propagation of the laser radiation through the multilayer polymer film. For a comprehensive understanding of the process, it is imperative to examine these processes in detail. Therefore, the interaction process is considered in depth and, especially, the propagation of the temperature field within the material, which is not directly accessible for real measurements, is analyzed exactly. For this purpose, on the one hand, a numerical temperature model is set up, which depicts the real experimental setup and takes into account the optical properties and heat conduction variables of the individual layers. The numerical model allows the temporal resolution of interaction processes within the multilayer polymer film to be viewed from different angles. On the other hand, thermographic images of the real samples are taken during the welding process. For this purpose, the emitted heat radiation of the polymer films is measured off-axis. The data obtained are evaluated and compared with each other. For the final discussion of the results, additional analyses of the weld specimens microscopy and thin sections are used.

Chitin production wastewater contains nutrient-rich organic and mineral contents. Coagulation of the wastewater with a natural coagulant such as by-product chitosan would be an economical and environmentally friendly method of treatment. This study investigated the treatment efficiencies of a preliminary sedimentation process followed by coagulation. The removal efficiencies for wastewater parameters were evaluated and compared for coagulants including by-product chitosan, polyaluminum chloride, and polyacryamide. The evaluation was based on the removal of wastewater turbidity and other criteria, including tCOD, sCOD, TKN, NH4+&ndash, N, TP, TSS, calcium, and crude protein. The results showed that the preliminary sedimentation (before coagulation) can remove over 80% of turbidity and more than 93% of TSS at pH 4 in 30 min. At optimal conditions, when the ratio of crude protein and calcium was 4.95, by-product chitosan dose of 77.5 mg&middot, L&minus, 1 and pH = 8.3, the wastewater characteristics changes were tCOD 23%, sCOD 32%, TKN and ammonium 25%, TP 90%, TSS 84%, Ca2+ 29%, and crude protein 25%. The residue recovered through coagulation consists of up to 55 mg&middot, g&minus, 1 crude protein, which is used for animal feed or crop fertilizer.