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The schematic of the separation and transfer of photogenerated charges over Mn-Fe-BTC/g-C 3 N 4 before contact and after contact. [Display omitted] • Bimetallic M-Fe-BTC/g-C 3 N 4 (M: Ni, Co, Cu, Zn, Mn) was synthesized via microwave-assisted method. • Direct Z-scheme heterojunction photocatalyst GCN/Mn-FeBTC has high ability to mineralize dye. • Synergistic effect of bimetalic M-Fe in the SBU network improves photocatalytic efficiency. • Bimetallic GCN/Mn-FeBTC could degrade nearly 100 % RR-195 within 30 min. Direct Z-scheme heterojunction photocatalyst GCN/M-FeBTC (M: Ni, Co, Cu, Zn, Mn; BTC: 1,3,5-benzenetricarboxylate, GCN: graphitic carbon nitrides) were synthesized by in-situ hydrothermal method assisted using microwave. GCN/M-FeBTC materials exhibit excellent photocatalytic performance with nearly 100 % of reactive red 195 (RR-195) being removed after 30 min under direct sunlight irradiation. Tests for reactive radicals have shown that holes (h+) and superoxide radicals (•O 2 –) close a major function in the removal of RR-195. Based on the band structure (BS) of the material, a direct Z-scheme heterojunction photocatalyst mechanism has been proposed. The effects of catalyst mass, pH and RY-145 concentration on the photocatalytic activity of GCN/Mn-FeBTC materials were also researched. The innovation of the photocatalytic activity of the GCN/Mn-FeBTC materials may be due to the synergistic combination of factors such as: (i) the high surface area; (ii) visible light absorption and efficient splitting of electron (e–) and h+; (iii) increased oxygen vacancies and defects; (iv) shortening of charge transport distances. The decomposition pathway of RR-195 was determined based on liquid chromatography mass spectrometry (LC-MS) analysis. Chemical oxygen demand (COD), biological oxygen demand (BOD) and total organic carbon (TOC) show high mineralization potential for the degradation of RR-195 on direct Z-scheme photocatalysts GCN/M-FeBTC. [ABSTRACT FROM AUTHOR]

Fuel cell hybrid electric vehicles (FCHEVs) have been recognized as a promising solution for green and sustainable transportation. Unfortunately, the low performance and high operational cost make current FCHEVs less attractive than their alternatives. In this paper, we address a new contribution to the optimal design for the FCHEV components’ parameters in order to enhance their performance and reduce their operating cost. We consider a passenger FCHEV and propose a parametric design method for its polymer electrolyte membrane fuel cell system, lithium-ion battery, electric motor and differential unit by the balancing composite motion optimization (BCMO) algorithm. The FCHEV model can be used to analyze the influence of the parameters of each of the aforementioned components. The desired performance, the hydrogen consumption, the efficiency of the fuel cell system, and the lifespan of the power sources are all taken into account through a single cost function. The optimization procedure is introduced, where the fuel cell maximal net power, battery capacity and maximal power capacity, motor maximal power, and powertrain gear ratio are optimally designed. Finally, comparative studies are conducted and validate the effectiveness of the proposed method.

Whole-genome sequencing and genome mining are recently considered an efficient approach to shine more light on the underlying secondary metabolites of Streptomyces. The present study unearths the biosynthetic potential of endophytic SX6 as a promising source of biologically active substances and plant-derived compounds for the first time. Out of 38 isolates associated with Aegiceras corniculatum(L.) Blanco, Streptomyces parvulusSX6 was highly active against Pseudomonas aeruginosaATCC® 9027™ and methicillin-resistant Staphylococcus epidermidis(MRSE) ATCC® 35984™. Additionally, S. parvulusSX6 culture extract showed strong cytotoxicity against Hep3B, MCF-7, and A549 cell lines at a concentration of 30 μg/ml, but not in non-cancerous HEK-293 cells. The genome contained 7.69 Mb in size with an average G + C content of 72.8% and consisted of 6,779 protein-coding genes. AntiSMASH analysis resulted in the identification of 29 biosynthetic gene clusters (BGCs) for secondary metabolites. Among them, 4 BGCs showed low similarity (28–67% of genes show similarity) to actinomycin, streptovaricin, and polyoxypeptin gene clusters, possibly attributed to antibacterial and anticancer activities observed. In addition, the complete biosynthetic pathways of plant-derived compounds, including daidzein and genistein were identified using genome mining and HPLC-DAD-MS analysis. These findings portray an exciting avenue for future characterization of promising secondary metabolites from mangrove endophytic S. parvulus.

Thiol-mediated uptake is emerging as a powerful method to penetrate cells. Cyclic oligochalcogenides (COCs) have been identified as privileged scaffolds to enable and inhibit thiol-mediated uptake because they can act as dynamic covalent cascade exchangers, i.e., every exchange produces a new, covalently tethered exchanger. In this study, our focus is on the essentially unexplored COCs of higher oxidation levels. Quantitative characterization of the underlying dynamic covalent exchange cascades reveals that the initial ring opening of cyclic thiosulfonates (CTOs) proceeds at a high speed even at a low pH. The released sulfinates exchange with disulfides in aprotic but much less in protic environments. Hydrophobic domains were thus introduced to direct CTOs into hydrophobic pockets to enhance their reactivity. Equipped with such directing groups, fluorescently labeled CTOs entered the cytosol of living cells more efficiently than the popular asparagusic acid. Added as competitive agents, CTOs inhibit the uptake of various COC transporters and SARS-CoV-2 lentivectors. Orthogonal trends found with different transporters support the existence of multiple cellular partners to account for the diverse expressions of thiol-mediated uptake. Dominant self-inhibition and high activity of dimers imply selective and synergistic exchange in hydrophobic pockets as distinguishing characteristics of thiol-mediated uptake with CTOs. The best CTO dimers with hydrophobic directing groups inhibit the cellular entry of SARS-CoV-2 lentivectors with an IC50significantly lower than the previous best CTO, below the 10 μM threshold and better than ebselen. Taken together, these results identify CTOs as an intriguing motif for use in cytosolic delivery, as inhibitors of lentivector entry, and for the evolution of dynamic covalent networks in the broadest sense, with reactivity-based selectivity of cascade exchange emerging as a distinguishing characteristic that deserves further attention.

This paper distinguished hydrogen roles to improve electron mobility and carrier concentration in ZnO and Al doped ZnO sputtered films. By combining experimental evidences and theoretical results, we find out that hydrogen located at oxygen vacancy sites (HO) is the main factor gives rise to increase simultaneously mobility and carrier concentration which has not been mentioned before. Introducing appropriate hydrogen content during sputtering not only results in crystalline relaxation but also supports doping Al into ZnO, increasing carrier concentration and electron mobility in the film. First principles calculations confirmed hydrogen substitutional stability for oxygen vacancy, significantly reducing electron conductivity effective mass and hence increasing electron mobility. In particular, 0.8% hydrogen partial pressure ratio achieved 61 cm2V−1s−1maximum electron mobility, optical transmittance above 82% in visible and near-infrared regions, and 2 × 1020 cm−3carrier concentrations for HAl co-doped ZnO film. These values approach ideal electrical and optical properties for transparent conducting oxide films. The presence of one maximum electron mobility was attributed to competition between increasing mobility due to restoring effective electron mass and hydrogen passivation of native defects, and decreased electron mobility due to electron-phonon scattering.

This Perspective focuses on thiol-mediated uptake, that is, the entry of substrates into cells enabled by oligochalcogenides or mimics, often disulfides, and inhibited by thiol-reactive agents. A short chronology from the initial observations in 1990 until today is followed by a summary of cell-penetrating poly(disulfide)s (CPDs) and cyclic oligochalcogenides (COCs) as privileged scaffolds in thiol-mediated uptake and inhibitors of thiol-mediated uptake as potential antivirals. In the spirit of a Perspective, the main part brings together topics that possibly could help to explain how thiol-mediated uptake really works. Extreme sulfur chemistry mostly related to COCs and their mimics, cyclic disulfides, thiosulfinates/-onates, diselenolanes, benzopolysulfanes, but also arsenics and Michael acceptors, is viewed in the context of acidity, ring tension, exchange cascades, adaptive networks, exchange affinity columns, molecular walkers, ring-opening polymerizations, and templated polymerizations. Micellar pores (or lipid ion channels) are considered, from cell-penetrating peptides and natural antibiotics to voltage sensors, and a concise gallery of membrane proteins, as possible targets of thiol-mediated uptake, is provided, including CLIC1, a thiol-reactive chloride channel; TMEM16F, a Ca-activated scramblase; EGFR, the epithelial growth factor receptor; and protein-disulfide isomerase, known from HIV entry or the transferrin receptor, a top hit in proteomics and recently identified in the cellular entry of SARS-CoV-2.

In this study, surface-enhanced Raman scattering substrates were investigated by the electrodeposition method to detect low concentrations of pesticides via the electrodeposition method with different agents from silver and gold precursors on APTES-modified ITO glass. A dual-potential method supplied three electrodes and was performed with a nucleation potential of 0.7 V for 2 s and a growth potential of −0.2 V for 500 s. The Ag film produced by the electrodeposition approach has great surface uniformity and good SERS signal amplification for the thiram insecticide at low concentrations. Interestingly, the ITO/APTES/Ag substrate extensively increased the sensitivity than the other investigated ones, thanks to the adequate assistance of amino groups of APTES in the denser and hierarchical deposition of Ag NPs. These observations were additionally elucidated via finite-difference time-domain (FDTD) calculation. For thiram, the detection was set at 10–8M with an enhancement factor of up to 3.6 × 107times. Comparing the SERS spectra of thiram at concentrations of 10–3, 10–4, and 10–5M with a relative standard deviation (RSD) of less than 7.0% demonstrates excellent reproducibility of the ITO/APTES/Ag substrate. In addition, the special selectivity of the ITO/APTES/Ag substrate for thiram demonstrates that these nanostructures can identify pesticides with extreme sensitivity.

Two β-galactosidases from Lactobacillus, including a heterodimeric LacLM type enzyme from Lactobacillus reuteriL103 and a homodimeric LacZ type β-galactosidase from Lactobacillus bulgaricusDSM 20081, were studied for immobilization on chitin using a carbohydrate-binding domain (chitin-binding domain, ChBD) from a chitinolytic enzyme. Three recombinant enzymes, namely, LacLM-ChBD, ChBD-LacLM, and LacZ-ChBD, were constructed and successfully expressed in Lactobacillus plantarumWCFS1. Depending on the structure of the enzymes, either homodimeric or heterodimeric, as well as the positioning of the chitin-binding domain in relation to the catalytic domains, that is, upstream or downstream of the main protein, the expression in the host strain and the immobilization on chitin beads were different. Most constructs showed a high specificity for the chitin in immobilization studies; thus, a one-step immobilizing procedure could be performed to achieve up to 100% yield of immobilization without the requirement of prior purification of the enzyme. The immobilized-on-chitin enzymes were shown to be more stable than the corresponding native enzymes; especially the immobilized LacZ from L. bulgaricusDSM20081 could retain 50% of its activity when incubated at 37 °C for 48 days. Furthermore, the immobilized enzymes could be recycled for conversion up to eight times with the converting ability maintained at 80%. These results show the high potential for application of these immobilized enzymes in lactose conversion on an industrial scale.

Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion−π interactions account for function. Rate enhancements maximize at 270 for anion−π catalysis on fullerenes and at 5100 M–1for autocatalysis. The occurrence of anion−π autocatalysis is confirmed with increasing initial rates in the presence of additional product. Computational studies on autocatalysis reveal transition state and product forming a hydrogen-bonded noncovalent macrocycle, like holding their hands and dancing on the active π surface, with epoxide opening and nucleophile being activated by anion−π interactions and hydrogen bonds to the product, respectively.

We investigated the effect of single and multidopants on the thermoelectrical properties of host ZnO films. Incorporation of the single dopant Ga in the ZnO films improved the conductivity and mobility but lowered the Seebeck coefficient. Dual Ga- and In-doped ZnO thin films show slightly decreased electrical conductivity but improved Seebeck coefficient. The variation of thermoelectric properties is discussed in terms of film crystallinity, which is subject to the dopants’ radius. Small amounts of In dopants with a large radius may introduce localized regions in the host film, affecting the thermoelectric properties. Consequently, a 1.5 times increase in power factor, three times reduction in thermal conductivity, and 5-fold enhancement in the figure of merit ZT have been achieved at 110 °C. The results also indicate that the balanced control of both electron and lattice thermal conductivities through dopant selection are necessary to attain low total thermal conductivity.

Objectives Though menstrual and reproductive factors have been associated with the risk of breast cancer in many populations, very few studies have been conducted among Vietnamese women. This study aimed to assess the association between menstrual and reproductive factors and the risk of breast cancer in Vietnamese women.Methods A retrospective case-control study of 490 breast cancer cases and 468 controls was conducted in Northern Vietnam. Unconditional logistic regression models adjusting for confounders were used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) for the associations of menstrual and reproductive factors with the risk of breast cancer; overall and by cancer subtype.Results Among breast cancer patients, the luminal B subtype was the most frequent (48.6%), followed by HER2-overexpressing (24.5%), luminal A (16.7%), and triple-negative breast cancer (TNBC; 10.2%). Among menopausal women, menopausal age at 50 years or older (OR = 1.71, 95% CI: 1.15-2.57 vs. <50 y) was associated with an increased risk of breast cancer. Earlier age at menarche (<13 y) was associated with a significantly increased risk of breast cancer (OR = 2.66, 95% CI: 1.08-7.51) among premenopausal women only and the luminal A subtype of breast cancer (OR = 3.06, 95% CI: 1.04-8.16). Having more than two children was associated with a reduced risk of premenopausal (OR = .42, 95%CI: .21-.83), luminal B (OR = .43, 95% CI: .24-.79), and TNBC (OR = .34, 95% CI: .14-.89). Later menopause was positively associated with the risk of breast cancer with HER2 overexpression (OR = 2.19, 95% CI: 1.14-4.23).Conclusion Associations of menstrual and reproductive factors with breast cancer among Vietnamese women, particularly for among premenopausal women and for the luminal A subtype, are generally consistent with those reported from other countries. These findings suggest that changes in menstrual and reproductive patterns among young Vietnamese women may contribute to the recent rising incidence of breast cancer in Vietnam.

Identification of spider mite species has been an important but complicated issue in pest control. We studied the species composition of spider mites collected in agricultural fields of northern Vietnam by using mitochondrial cytochrome oxidase subunit I sequences as a case study of the DNA barcoding identification technique for spider mites. Specimens were identified by comparing obtained DNA sequences with known sequences deposited in DNA databases. If phylogenetic analysis was used together, the DNA barcoding approach was useful for species identification of spider mites, especially for the genus Tetranychus. Using DNA barcoding, we classified most of the Vietnamese samples into Tetranychus kanzawai Kishida, T. urticae Koch and T. truncatus Ehara.

Microelectromechanical systems (MEMS) including microchemical devices have been widely concerned, in particular, when made of an extremely stable ceramic material for their use at harsh conditions. SiCBN preceramic polymer was derived from borazine (B3N3H6) modified allylhydridopolycarbosilane (AHPCS) via hydroboration of allyl groups with B-H groups at 0oC for 24 h by following the standard Schenk technique. The extent of polymer-to-ceramic conversion with an ultimate ceramic yield of 92 wt% was investigated by simultaneous TGA, 1H, 13C-NMR, IR, and XRD measurements. The polymer-derived SiCBN ceramic remained as an amorphous solid up to 1400oC. The ceramic product obtained after pyrolysis at 1000-1400oC exhibited excellent oxidation resistance in air. In addition, ceramic microstructures were fabricated by employing soft lithographic technique.

We present the operational principles and analytical characteristics of several all-optical modulators and switches that incorporate nonlinear directional couplers with either single or double biasing beams. Graphic representation and potential-well models are used effectively to describe the device’s operation and enhance the ability to anticipate its performance. Phase-to-amplitude modulation is considered, which leads to the special case of phase-controlled switching. Amplitude-to-amplitude modulation is studied, which leads to optical amplification phenomena. An intensity-sensitive switch is also examined.

Conductivity σ and thermal conductivity κ are directly related to carrier concentration while Seebeck coefficient S is inversely proportional to carrier concentration. Therefore, improving thermoelectric (TE) performance is challenging. Here, the first-time analysis of secondary phase-controlled TE performance in terms of density-of-state effective mass md∗, weighted mobility μwand quality factor Bis discussed in ZnO system. The results show that the secondary spinel phase Ga2O3(ZnO)9not only impacts on κbut also on σand Sat high temperature, while the effect of carrier concentration seem to be dominant at low temperature. For the high-spinel-segregation sample, a compensation of dopant atoms from the spinel to substitutional sites in the ZnO matrix at high temperature leads to a low decreased rate of temperature-dependent md∗. The compensation process also induces a band sharpening, a small μwreduction, and a large Benhancement. As a result, In and Ga co-doped ZnO bulk with the highest spinel segregation achieves the greatest PFimprovement by 112.8%, owing to enhanced Seebeck coefficient by 110% as compared to the good Zn-substitution sample.

In this work, we have performed a thorough study of the mobility in 'Si / s-Ge / Si' QW heterostructure pMOSFETs. Through experiments and detailed simulations, the effects of the s-Ge quantum well (QW) thickness and quantum confinement effects on the hole mobility of both, single-gate (SG) and double-gate (DG) QW pMOSFETs have been explored.