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In the process of electroreduction of carbon dioxide (eCO2RR) to multi‐carbon (C2+) products, it is imperative to enhance the concentration of key intermediate species on the catalyst surface. The utilization of micro‐nano reactors to achieve confinement effects has been widely observed in various catalytic reactions, yet it has seldom been employed in eCO2RR. Here, we present a novel nanoreactor composed of stacked CuS nanosheets for eCO2RR to C2+ products. In comparison to catalyst comprising of nanosheet with open space, the C−C coupling within this confined nanospace is significantly enhanced, resulting in the increase of Faraday efficiency (FE) of C2+ products to 53 %. In situ infrared (IR) spectroscopy reveals the confinement and enrichment of key intermediate by the nanoreactor. Our research findings demonstrate that a meticulously designed nanoreactor can elevate the selectivity of C2+ products, thereby aiding in the design of eCO2RR catalysts. [ABSTRACT FROM AUTHOR]

In this study, we examined the relation of observed classroom practices to language and literacy achievement and the moderation of this relation for students from pre-K to sixth grade. A total of 136 studies (N = 107,882 participants) met the inclusion criteria, of which 108 studies were included for meta-analysis and the other 28 studies were narratively synthesized. The average zero-order (r =.12) and partial correlations (rp =.04) were statistically significant but weak in magnitude. The relation was slightly weaker in upper than in lower grade levels, and stronger for observations capturing macro quality and instructional dimension than those capturing micro measurement and emotional or structural dimension, respectively. The relation did not vary by observation duration, frequency, adopted statistical approach, or type of covariates. Taken together with the narrative synthesis, the results highlight the complex nature of classroom observation and a need for more classroom research, particularly on higher grade levels. [ABSTRACT FROM AUTHOR]

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity. [ABSTRACT FROM AUTHOR]

Single atom alloy (SAA) catalysts have been recently explored for promotion of various heterogeneous catalysis, but it remains unexplored for selective electrocatalytic reduction of carbon dioxide (CO2) into multi‐carbon (C2+) products involving C−C coupling. Herein we report a single‐atomic Bi decorated Cu alloy (denoted as BiCu‐SAA) electrocatalyst that could effectively modulate selectivity of CO2 reduction into C2+ products instead of previous C1 ones. The BiCu‐SAA catalyst exhibits remarkably superior selectivity of C2+ products with optimal Faradaic efficiency (FE) of 73.4 % compared to the pure copper nanoparticle or Bi nanoparticles‐decorated Cu nanocomposites, and its structure and performance can be well maintained at current density of 400 mA cm−2 under the flow cell system. Based on our in situ characterizations and density functional theory calculations, the BiCu‐SAA is found to favor the activation of CO2 and subsequent C−C coupling during the electrocatalytic reaction, as should be responsible for its extraordinary C2+ selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of Fe addition and ion irradiation on hardening behavior in Zr alloys is experimentally investigated. • The formation of dislocation loops and amorphization of precipitation particles are facilitated through ion irradiation. • The quantitative contribution of underlying hardening mechanisms in irradiated Zr alloys is theoretically analyzed. • Theoretical results match well with different sets of unirradiated and ion-irradiated experimental data. Exploring the effect of Fe addition and ion irradiation on surface hardness in Zr alloys not only elucidates the strengthening mechanisms of individual alloying elements but also facilitates the assessment of mechanical properties under varying damage levels. In this work, the microstructural variations and surface hardness of Zr and Zr-Fe alloys were examined through Ne+ and Au3+ irradiation experiments. Electron backscatter diffraction (EBSD) characterization suggested the potential of Fe addition in Zr-Fe alloys for grain refinement. Transmission Electron Microscopy (TEM) observations indicated the formation of dislocation loops in irradiated materials, accompanied by a transformation of Zr 3 Fe particles from a crystalline to an amorphous state. Furthermore, nano-indentation tests were employed to measure the depth-dependent hardness, revealing an augmentation in hardness with increasing Fe content and highlighting noticeable irradiation hardening in Zr alloys. A mechanical model was then developed to theoretically investigate the contribution of diverse hardening mechanisms in ion-irradiated Zr alloys, particularly addressing the impact of non-uniformly distributed defects. Theoretical analysis denoted that the irradiation-induced defects hardening at varying depths follows distinct laws, whereas the precipitation hardening in Zr-Fe alloys was attributed to high-density strengthening particles induced by Fe addition. Moreover, it was determined that the surface hardness is governed by geometrically necessary dislocations (GNDs) and irradiation-induced defects at shallow depths, whereas precipitates and statistically stored dislocations (SSDs) dominate at relatively larger depths. [ABSTRACT FROM AUTHOR]

The monoclinic diopside structured CaMgGe 2 O 6 dielectric ceramics were synthesized by the traditional solid-phase reaction method, and their microwave dielectric properties were characterized. X-ray diffraction (XRD) and Rietveld refinement revealed that CaMgGe 2 O 6 belongs to the monoclinic system of space group C2/c. SEM images showed that dense CaMgGe 2 O 6 ceramics could be formed at the optimum sintering temperature of 1300 °C. Typically, ceramic sintered at 1300 °C for 6 h possessed outstanding microwave dielectric properties with ε r ∼7.96, Q × f ∼41,280 GHz, and τ f ∼ −46.6 ppm/°C. Far-infrared spectra analysis revealed the intrinsic microwave dielectric properties of CaMgGe 2 O 6 ceramics. These findings demonstrate promising application prospects of CaMgGe 2 O 6 in microwave substrate materials. [ABSTRACT FROM AUTHOR]

Introduction: KLRB1 is a gene encoding CD161 expressed in NK cells and some T cell subsets. At present, KLRB1 is believed to affect tumorigenesis and development by regulating the cytotoxicity of NK cells in several cancers. However, there is a lack of systematic reviews of KLRB1 in a variety of malignancies.Objectives: Hence, our research is aimed at providing a relatively comprehensive understanding of the role of KLRB1 in different types of cancer, paving the way for further research on the molecular mechanism and immunotherapy potential of KLRB1.Methods: In this study, we used relevant public databases, including TCGA (The Cancer Genome Atlas), GEO (Gene Expression Omnibus), CCLE (Cancer Cell Line Encyclopedia), GTEx (Genotype Tissue-Expression), and HPA (Human Protein Atlas), to perform a pan-cancer analysis of KLRB1 across 33 types of cancer. We explored the potential molecular mechanism of KLRB1 in clinical prognosis and tumor immunity from the aspects of gene expression, survival status, clinical phenotype, immune infiltration, immunotherapy response, and chemotherapeutic drug sensitivity.Results: KLRB1 was downregulated in 13 cancers while upregulated in kidney cancer. Patients with high expression of KLRB1 have a better prognosis in most types of cancer. Moreover, the KLRB1 expression level is related to TMB and MSI and related to various immune signatures of tumor. The expression of KLRB1 can affect tumor immune cell infiltration. KLRB1 expression level can also affect the sensitivity of chemotherapy drugs.Conclusions: KLRB1 may be a prognostic and immunological biomarker across tumors. At the same time, KLRB1 expression can reflect the sensitivity of cancer patients to chemotherapy drugs. KLRB1 may become a new target for immunotherapy. [ABSTRACT FROM AUTHOR]

Microstructure and texture evolution of β-quenched Zr-xNb-0.4Mo (x = 0, 0.4, 0.6 and 1.0 wt %) alloys during the cold rolling process were systematically investigated. The Zr-xNb-0.4Mo alloys exhibit the area fractions of the martensitic structure are 33.2%, 69.4%, 100% and 100% with an increase in Nb content. Under the same rolling gap (1.2 mm), the rolling reductions are 24%, 28%, 29.7% and 30%, respectively. To understand the reason for the gradual increase of rolling reductions until approximately 30%, a visco-plastic self-consistent (VPSC) model was employed to predict the texture evolution and relative activity of different deformation modes. The variation of average Schmid factors (SFs) and the variation of the relative activity of different deformation modes before and after cold rolling were calculated and compared. With the increase of Nb content, a similar variation law between the variation of average SF and the variation of relative activity was found. The basal slip in Zr-0.4Nb-0.4Mo alloy is difficult to activate due to the initial texture of Zr-0.4Nb-0.4Mo alloy. Pyramid slip can accommodate the strain along the normal direction (ND), which is beneficial to the high plasticity of Zr alloys during cold rolling. By comparing the variation of average SF of pyramid slip, it is found that the larger rolling reductions of Zr-0.6Nb-0.4Mo alloy and Zr-1.0Nb-0.4Mo alloys can be attributed to the activation of pyramid slip. The existence of primary α grains can decrease the average SF and inhibit the activation of pyramid slip. The cold rolling can make the martensite plates crushed and refined, but not to the primary α grains. [Display omitted] • The texture evolution of β-quenched Zr-xNb-0.4Mo alloys under rolling is studied. • The smaller rolling reductions can be attributed to the existence of primary α grains. • The primary α grains decrease the average SF of pyramid slip. • The primary α grain can restrict the activation of pyramid slip. • The cold rolling can make martensite plates crushed and refined, but not to primary α grains. [ABSTRACT FROM AUTHOR]

The cobalt metal–organic frameworks (Co-MOFs) were efficiently prepared by ultrasonic-assisted ball milling with low cost, utilizing 1, 3, 5-benzenetricarboxylic acid and cobalt (II) acetate tetrahydrate. The structural characteristics were carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry (TGA), and BET surface areas method. The adsorption of Co-MOFs to Congo Red (CR) was analyzed by Langmuir adsorption isotherm and pseudo-second-order kinetic model. The results showed that the maximum adsorption performance (fitted by Langmuir adsorption isotherm) of the Co-MOFs (with 30 min's synthesis time and 1:1 molar ratio of the raw material) to CR reached 1.76 × 103 mg/g, which is much higher than previous reports. The adsorption experiment reached equilibrium in 30 min. Electrostatic attractions, π–π stacking interactions and pH are considered to play a significant role in the adsorption of Co-MOFs to CR. The adsorption rate of Co-MOFs to CR remains 34% even after it is recycled for the third time. In this paper, the absorption results indicated that Co-MOFs prepared by ultrasonic-assisted ball milling presents a great prospect in the field of CR adsorption. [ABSTRACT FROM AUTHOR]

The current study replicated an earlier investigation by Bouwer and van der Veen (2023) where 10 Grade 5 and 6 classrooms in the Netherlands (210 students) were randomly assigned to a treatment or control condition, with treatment students evidencing improvements in the quality of their essays after practice writing argumentative essays, reading and discussing them with a small group of peers, and revising each essay based on the discussion that ensued. In the present study, 12 Grade 2 to 4 classrooms in Türkiye (383 students) were randomly assigned to this write, talk, and rewrite dialogic treatment or to a control condition. Students in the control condition practiced planning and writing the same four argumentative essays as treatment students did during the experiment, and each of these essays was shared with peers (time spent in both conditions was comparable). Control students did not, however, discuss their essay with peers or use such feedback to revise them as was done by students in the write, talk, and rewrite dialogic treatment. When the nested nature of the data and pretest scores were held constant, the quality of the argumentative posttest essays produced by students in the treatment condition evidenced greater improvement than essays written by control students. The same outcome was obtained for the length of essays (number of words) when the nested nature of the data and pretest scores were held constant. This investigation provided evidence that the write, talk, and rewrite dialogic intervention tested by Bouwer and van der Veen (2023) was effective in improving the argumentative writing of even younger students in a different country. Implications for research and practice are provided. [ABSTRACT FROM AUTHOR]

To assess the effect of addition of probiotics and carbon source on the microbial community structure within the shrimp culture, an enclosure system simulating a high density, intensive aquaculture of Litopenaeus vannamei was set up in Dianbai, Maoming, Guangdong province, China. The phylogenetic profiles of microbial communities in the enclosure system after addition of Bacillus and molasses were studied in the middle and final culture season (on the 45th, 75th and 95th day) using polymerase chain reaction-denaturing gradient gel electrophoresis. A total of four groups, each containing a triplicate were set up: Group A (control), Group B (64% of daily feed was provided as molasses with Bacillus sp.), Group C (50% of daily feed amount provided as molasses with Bacillus sp.) and Group D (64% of daily feed amount as molasses alone). The results showed that α- Proteobacteria, δ- Proteobacteria, Bacteroidetes and Actinobacteria were the dominant bacteria. Moreover, the relative proportion of α- Proteobacteria increased and that of Bacteroidetes decreased gradually with time. Pathogenic Flexibacter was the dominant genus in Group A on the 45th day, while the functional strains ( Sphingomonas sp., Erythrobacter sp. , Roseobacter sp., and Rhodobacter sp.) were detected multiple times in Groups B and C. Bacillus sp. was the cultivable, dominant bacterium in Groups B and C on the 95th day. Therefore, the combined use of Bacillus and molasses helped increase diversity of the microbial community, effectively inhibit pathogens, and promote the formation and development of a beneficial microbial community structure in the high density, intensive aquaculture of L. vannamei. [ABSTRACT FROM AUTHOR]

Although many efforts have been made on understanding the variant selection rules, the interplay of these rules and their combined effects on variant selection have not been well addressed. In this work, variant selection and morphology by the different cooling rates in Zr-xNb-0.4Mo (x=0.2, 0.6 and 1.0 wt.%) alloys are characterized using scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) technique. The results show that the variation of variant selection and morphology is attributed to the Nb content, the parent β grain size, the cooling rate, the β grain boundary (GB) characteristics and the interplay among them. The Nb addition (Nb≤0.6 wt.%) decreases the average grain size of parent β grains, and the smaller parent β grain size generally results in the larger degree of variant selection (DVS) values in the individual parent β grain due to their resistance to the uniform nucleation and growth of α-variants. The slow cooling rate promotes the diffusional transformation and favors the formation of special β GBs and the β GBs with high dislocation density, which usually lead to a stronger DVS in the individual parent β grains. The very large weighted area percentage of α-variant in the individual parent β grains, which accounts for the stronger DVS in the individual parent β grains, is due to the special β GBs, the β GBs with high dislocation density and the incomplete martensitic transformation (martensitic-diffusional mixed transformation). The β GB with high dislocation density has a larger contribution to the strong DVS of individual parent β grains than the special β GB. In addition, the result shows that the low density of statistically stored dislocations (SSDs) can inhibit the nucleation and growth of the α-variant produced by the special β GB. [Display omitted] [ABSTRACT FROM AUTHOR]

There is considerable concern that many adolescents do not attain the writing competence needed to be successful in school, their personal lives, or the workplace. Ensuring that students acquire this competence is a basic responsibility of schools. In order to meet this objective, teachers need access to effective practices for teaching writing. In this meta-analysis, we examined if teaching writing improved the writing and reading of students in Grades 6–12, and what specific writing treatments enhanced students' writing. Our review included writing treatments tested using an experimental or quasi-experimental design (with pretests) and published and unpublished studies, and computed effect sizes (ESs) for all writing and reading outcomes assessed. Across 406 independent comparisons, yielding 3,514 ESs involving 52,529 students, teaching writing had a positive and statistically detectable impact on students' writing (ES = 0.47) and reading (ES = 0.22). Moreover, a variety of different writing treatments improved students' performance on writing measures. Across all writing outcomes, statistically detectable effects (presented in parentheses) were obtained for comprehensive writing programs (0.47; which included the process approach to writing), strategy instruction (0.76), digital writing tools (0.31), transcription instruction (0.71), computer-assisted instruction (0.32), teaching critical/creative thinking skills for writing (0.27), emulating good models of writing (0.46), feedback (0.34), goal setting (0.44), prewriting activities (0.49), grammar instruction (0.77), sentence instruction (0.73), inquiry (0.92), observing writers/readers, peer assistance (0.41), summarization instruction (0.49), and text structure instruction (0.39). Implications for practice, research, and theory are discussed. Educational Impact and Implications Statement: In this meta-analysis, we identified instructional practices that improve the writing of students in Grades 6–12. We found that multiple procedures can improve these students' writing including the process writing approach, setting writing goals, prewriting and inquiry activities for gathering and organizing writing content, emulating models of good writing, writing with digital tools, peers assisting each other with writing, students observing other writers and readers interacting with text, as well as teaching writing strategies, grammar, spelling, sentence construction, summary writing, creative or critical thinking skills, and text structure instruction. Teaching writing also improved Grade 6–12 students' reading. [ABSTRACT FROM AUTHOR]

The microstructure and texture evolution of Zr-xNb-0.4Mo (x = 0, 0.2, 0.4, 0.6 and 1.0 wt%) alloys are characterized using scanning electron microscopy (SEM), transmission electron microscope (TEM) and electron backscatter diffraction (EBSD) technique. The aim is to elucidate the role of primary α grains in the degree of transformation texture obeying the Burgers orientation relationship (OR) in Zr alloys. The primary α grain is produced by adjusting Nb content in Zr alloys. The crystallographic orientations of Zr-xNb-0.4Mo alloys show that the degree of transformation texture obeying the Burgers OR increases with the proportion of primary α grains decreasing. Until no primary α grains exist, the transformation texture obeys the Burgers OR strictly. The primary α grains can exert great influence on variant selection by restricting the growth of high-temperature β grains and acting as nucleation sites. The fact that primary α grains are the origins of variant selection is observed. Meanwhile, variant selection occurs in both the duplex microstructure and full martensite plates during the water-quenching process. The texture weakening of the duplex microstructure is attributed to the new texture components given by martensite plates. In terms of microstructure, a series of precipitates, Zr 3 (Nb, Mo, Fe), are found in a primary α grain. • The degree of transformation texture obeying the Burgers OR is studied. • The result shows that primary α grains are the origins of variant selection. • Texture weakening is attributed to the new components given by martensite. • Some precipitates, Zr 3 (Nb, Mo, Fe), were found in the primary α grains. [ABSTRACT FROM AUTHOR]

This article describes CO2 flows in the Earth's ecosystem. It also describes how CO2 is made use of in various market sectors - as a raw material in the synthesis of plastics and fuels, during extraction in the food and perfume industries, for the transfer of heat in heating and refrigeration systems, and in the breeding of genetically modified algae for the production of biofuels. Additionally, the article explores the possibility of reducing atmospheric CO2 concentrations and the anthropogenic modification of natural flows between the various subsystems in the Earth's ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: A “cradle-to-grave” life cycle assessment was conducted to examine the energy and greenhouse gas (GHG) emission footprints of two emerging sludge-to-energy systems. One system employs a combination of anaerobic digestion (AD) and fast pyrolysis for bioenergy conversion, while the other excludes AD. Each system was divided into five process phases: plant construction, sludge pretreatment, sludge-to-bioenergy conversion, bioenergy utilizations and biochar management. Both systems achieved energy and GHG emission benefits, and the AD-involving system performed better than the AD-excluding system (5.30 vs. 0.63GJ/t sludge in net energy gain and 0.63 vs. 0.47t CO2eq/t sludge in emission credit for base case). Detailed contribution and sensitivity analyses were conducted to identify how and to what degree the different life-cycle phases are responsible for the energy and emission impacts. The energy and emission performances were significantly affected by variations in bioenergy production, energy requirement for sludge drying and end use of bioenergy. [Copyright &y& Elsevier]

Abstract: Energy recovery from sewage sludge offers an opportunity for sustainable management of sewage sludge and energy. Anaerobic digestion and pyrolysis are among the most promising processes applicable for sewage sludge-to-energy conversion. Anaerobic digestion of sewage sludge forms methane-rich biogas, which can be utilized as fuel to offset heat and electricity consumption of the wastewater treatment sector. However, the digestion process has the limitation that it cannot sufficiently extract the energy in sewage sludge. The digested sludge is still energy profitable in that it contains considerable organic matter, but poor in biodegradability. Sludge pyrolysis is an innovative process that can convert both raw and digested sludge into useful bioenergy in the form of oil and gas, forming biochar as a byproduct that is environmentally resistant and holds potential for carbon sequestration and soil conditioning. It is expectable that sludge pyrolysis would step into practical deployment in the near future. This paper presents a brief overview of anaerobic digestion and pyrolysis in the application to bioenergy production from sewage sludge. An assessment of energy conversion efficiency of two parallel sludge-to-energy pathways is also presented. One pathway relies on an exclusive pyrolysis process (fed with raw sludge) while the other is based on anaerobic digestion followed by pyrolysis (fed with the digested sludge). The pathway via the combination of anaerobic digestion and pyrolysis could achieve higher energy efficiency compared to the pathway employing the pyrolysis alone. [Copyright &y& Elsevier]

Abstract: The demand for high purity d-a-tocopheryl polyethylene glycol 1000 succinate (TPGS) is increasing with the exploitation of TPGS-related products. Previously, we synthesized a TPGS mixture by esterifying vitamin E succinate with polyethyleneglycol 1000. In this study, a temperature-modulated silica gel chromatographic column was used to purify the synthesized TPGS. Taguchi method was used to optimize purification conditions associated with column temperature, loading amount, feedstock concentration and flow rate of mobile phases. Purification efficacy under the Taguchi optimized conditions was predicted theoretically and the predicted results were verified experimentally. High-performance liquid chromatography was used to quantify the unpurified and purified TPGS. The Taguchi-based analysis separately produced an optimum combination of purification conditions for TPGS purity and recovery. Under the optimized conditions, both the theoretical prediction and the confirmatory experiment yielded TPGS purity and recovery approximating to 98% each. Impressively, the study also found that column temperature had a considerable effect on purification efficacy, in particular on TPGS purity, although it was a less influential factor compared to loading amount and feedstock concentration. [Copyright &y& Elsevier]

The improper use of antibiotics has led to the development of bacterial resistance, resulting in fewer antibiotics for many bacterial infections. Especially, the drug resistance of hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is distinctly serious. This research designed and synthesized two series of 3-substituted ocotillol derivatives in order to improve their anti-HA-MRSA potency and synergistic antibacterial activity. Among the synthesized compounds, 20–31 showed minimum inhibitory concentration (MIC) values of 1–64 µg/mL in vitro against HA-MRSA 18–19, 18–20, and S. aureus ATCC29213. Compound 21 showed the best antibacterial activity, with an MIC of 1 μg/mL and had synergistic inhibitory effects. The fractional inhibitory concentration index (FICI) value was 0.375, when combined with chloramphenicol (CHL) or kanamycin (KAN). The structure–activity relationships (SARs) of ocotillol-type derivatives were also summarized. Compound 21 has the potential to be developed as a novel antibacterial agent or potentiator against HA-MRSA. [ABSTRACT FROM AUTHOR]

Ginseng is one of the most widely consumed herbs in the world and plays an important role in counteracting fatigue and alleviating stress. The main active substances of ginseng are its ginsenosides. Ocotillol-type triterpenoid is a remarkably effective ginsenoside from Vietnamese ginseng that has received attention because of its potential antibacterial, anticancer and anti-inflammatory properties, among others. The semisynthesis, modification and biological activities of ocotillol-type compounds have been extensively studied in recent years. The aim of this review is to summarize semisynthesis, modification and pharmacological activities of ocotillol-type compounds. The structure–activity relationship studies of these compounds were reported. This summary should prove useful information for drug exploration of ocotillol-type derivatives. [ABSTRACT FROM AUTHOR]

The dynamics of water droplets on fiber layers are investigated by fiber-scale simulation using volume of fluid (VOF) method. The effects of fiber spaces, contact angles at fibers and numbers of layers on droplet dynamics are investigated. Force analysis for the pinned and moving droplets on fiber layers shows that the resistant forces from the wetted fibers at the edge positions rather than middle positions are the dominant force to control the droplet mobility. Force analysis for droplets on the dual-layers fiber layer are also conducted. The results show that the second layer contributes little to hinder the droplet directly due to the insignificant resistant force they provided. However, the second fiber layer enhances the total resistant force from the first layer. Furthermore a simplified model is used to compare with the fiber model. The results indicate that the simplified model can also be used to predict the droplet mobility once the contact angle is given. [Display omitted] • Fiber scale numerical modeling of droplets on fiber layers is conducted. • Resistant forces from the fibers at the edge positions are the dominant forces. • The total resistant forces from the first layer dominate the droplet motion. • Simplified model neglected fiber structure is compared with the fiber model. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the microstructure information and mechanical behavior of ion-irradiated zirconium (Zr) alloys through a combination of experimental measurements and theoretical analysis. Experimental procedures involved Au3+ irradiation of Zr-1.5Sn-0.2Fe-0.1Cr and Zr-1.0Sn-1.0Nb-0.1Fe at 3 displacements per atom (dpa) and 30 dpa. Transmission electron microscopy analysis revealed the formation of precipitates such as Zr(Fe, Cr) 2 in Zr-1.5Sn-0.2Fe-0.1Cr, as well as β -Nb and Zr(Nb, Fe) 2 in Zr-1.0Sn-1.0Nb-0.1Fe. These precipitates exhibited a transformation from crystalline state to partial or complete amorphization after ion-irradiation. Furthermore, macroscopic mechanical properties of the Zr alloys were characterized by nano-indentation tests, which revealed a significant indentation size effect (ISE) and irradiation hardening behavior. To provide a theoretical understanding of the depth-dependent hardness observed in ion-irradiated Zr alloys, a mechanistic model was developed to address the different expansion rates of the plastic zone in the irradiated and unirradiated region. The results indicated that the ISE phenomenon could be attributed to the reduction in the density of geometrically necessary dislocations (GNDs) caused by the expansion of the plastic zone. In addition, the irradiation hardening behavior primarily resulted from the contribution of irradiation-induced defects. With increasing indentation depth, the dominant hardening mechanisms changed from the contribution of irradiation-induced defects, GNDs and statistically stored dislocations (SSDs) in the irradiated region to SSDs in the unirradiated substrate. • The microstructure and mechanical behavior of ion-irradiated Zr alloys are studied by experimental and theoretical analysis. • Second phase particles are transformed from crystalline state to partial or complete amorphization after ion-irradiation. • A mechanistic model is developed to address the different expansion rates of the plastic zone. • Theoretical results match well with the irradiated experimental data. [ABSTRACT FROM AUTHOR]

Superhydrophobic SiO 2 was rapidly synthesized from commercial SiO 2 (KH550–SiO 2) at room temperature by innovatively using ultrasound-assisted ball milling. Characterization results showed that N-octyltriethoxysilane was grafted onto KH550–SiO 2 via multiple forces. Superhydrophobic paints were prepared by introducing epoxy resin as a binder. The preparation process is fluorine-free and green. Superhydrophobic paints can easily establish superhydrophobic coating on different substrates through multiple routes, and the prepared coating highlights excellent hydrophobicity, mechanical stability, and durability. Furthermore, the superhydrophobic coating displays superior self-cleaning, antifouling, oil-water separation, and load-increasing properties. We are sure that this work provides a novel green, fast, and scalable route for the synthesis of superhydrophobic nanoparticles. Also, it can promote the engineering applications of superhydrophobic coating. [ABSTRACT FROM AUTHOR]

Superhydrophobic SiO 2 was rapidly synthesized from commercial SiO 2 (KH550–SiO 2) at room temperature by innovatively using ultrasound-assisted ball milling. Characterization results showed that N-octyltriethoxysilane was grafted onto KH550–SiO 2 via multiple forces. Superhydrophobic paints were prepared by introducing epoxy resin as a binder. The preparation process is fluorine-free and green. Superhydrophobic paints can easily establish superhydrophobic coating on different substrates through multiple routes, and the prepared coating highlights excellent hydrophobicity, mechanical stability, and durability. Furthermore, the superhydrophobic coating displays superior self-cleaning, antifouling, oil-water separation, and load-increasing properties. We are sure that this work provides a novel green, fast, and scalable route for the synthesis of superhydrophobic nanoparticles. Also, it can promote the engineering applications of superhydrophobic coating. [ABSTRACT FROM AUTHOR]

Although previous studies have investigated the occurrence of antibiotic resistance genes (ARGs) in aquaculture, few have monitored the concentrations and propagation of ARGs in biological tissues or investigated the key factors influencing their spread in aquaculture. This study investigated the concentration, propagation, and distribution of ARGs and bacterial communities in water sources, pond water, and tilapia tissues, and their key influencing factors, in a typical tilapia farm. ErmF, sul1, and sul2 were the dominant ARGs with high concentrations. The total concentrations of ARGs (TCAs) in tilapia tissues decreased in the following order: stomach > scales > intestine > gills (P < 0.05). Redundancy analysis and multiple linear regression revealed that suspended solids (SS) and chemical oxygen demand (COD) were positively correlated with the dominant ARGs ermF sul2, and the TCAs (P < 0.05); additionally, Chloroflexi and Bacteroidetes in tilapia aquaculture water were positively correlated with the dominant ARGs ermF and sul2, as well as the TCAs (P < 0.05). This study suggests that SS and COD were the key factors driving the distribution and spread of ARGs in tilapia aquaculture water. Additionally, Chloroflexi and Bacteroidetes were the key bacterial flora affecting the propagation of ARGs in tilapia aquaculture systems. [ABSTRACT FROM AUTHOR]

Abstract A series of novel fusidic acid (FA) derivatives were synthesized and screened for their in vitro cytotoxicity against the Hela, U87, KBV and MKN45 cancer cell lines. Selected FA derivatives with anti-tumor activity were firstly identified including compound 4 , which exhibited good anti-proliferative activity with IC 50 values in the range of 1.26–3.57 μ M. Further research revealed that compound 4 induced Hela cells to undergo apoptosis by increasing the ratio of the cells in the Sub-G 0 /G 1 phase via decreasing the neo-synthesized proteins in a dose-dependent manner from 1 to 10 μ M. Compound 4 also showed good in vivo anti-tumor activity against the xenograft tumor of Hela cells and had no apparent toxicity. This study highlights the advantage of introducing the medium-length amino-terminal groups at the 3-OH position of FA to enhance its anti-tumor activity and suggests that compound 4 provides a starting point for designing more potent derivatives in the future. Graphical abstract Image 1 Highlights • Fusidic acid (FA) derivatives with anti-tumor activity were first discovered. • A preliminary structure-activity relationship of the anti-tumor activity was described. • One novel derivative 4 exhibited good anti-tumor activity both in vitro and in vivo. • The mechanism that compound 4 induced Hela cells to undergo apoptosis was first proved. [ABSTRACT FROM AUTHOR]

A 3D + 1D model is developed to investigate the effect of liquid water in cathode channels on oxygen transportation. The gas-liquid interface is tracked by volume of fluid (VOF) method and the oxygen transportation is solved by a species transport model. It is found that the existence of liquid water in channels can hinder the transportation of oxygen towards catalyst layers. The water coverage is a key factor that affects the oxygen transportation. It is influenced by the droplet numbers, volumes, contact angles and liquid regimes. Compared to the case with 0 droplet, the current densities for the cases with 6 and 12 droplets decrease by 1.4% and 10.6% respectively, for the cases with a droplet volume of 0.05 μL, 0.1 μL, 0.2 μL and 0.3 μL decrease by 1.7%, 3.9%, 9.6% and 14.9% respectively, for the cases with the contact angles of 115°, 125°, 135°, 145° and 155° decrease by 15.2%, 13.8%, 9.6%, 6.6% and 5.3% respectively. Compared to the droplet regime, the current densities of the film regime with the water volume of 1.2 μL and 2.4 μL increase by 3.6% and 9.4% respectively. [Display omitted] • An improved method to couple VOF model with species transport model. • Water coverage ratio of 20.7% can cause 14.9% declines of current density. • Film flow results in less cell performance loss but is difficult to discharge. [ABSTRACT FROM AUTHOR]

Microbiota carrying antibiotic and metal resistance genes pose increasing threats to human health. The profiles of the abundance and dissemination of the extracellular and intracellular antibiotic resistome (ARO) and metal resistome (MRO) in aquaculture environments and reared organisms, and their interrelationships, intrinsic connections, and driving factors are poorly understood. The purpose of this study was to investigate the changes in the extracellular and intracellular ARO and MRO abundances and their key driving factors during the rearing process in tilapia aquaculture. The results show that the abundance of the ARO was strongly positively correlated with that of the MRO (p < 0.01). The correlation coefficients between the abundances of plasmids and the ARO as well as MRO were 0.93 and 0.97, respectively (p < 0.05). Redundancy analysis (RDA) showed that plasmids were significantly positively correlated with the ARO and MRO in tilapia aquaculture water (p < 0.05), while multivariable linear regression analysis showed that plasmids were significantly and positively correlated with the MRO (p < 0.01). Network analysis and RDA showed that Actinobacteria were significantly positively correlated with ARO and MRO. The results of this study indicate that the extracellular ARO is a preponderant form of and significant contributor to antibiotic resistance. Combined ARO and MRO contamination could be positively driven and exacerbated by plasmids through propagation. The bacterial flora is an intrinsic bridge between the ARO and MRO. Mobile genetic elements, especially plasmids, are key drivers of their spread. Based on the results of this study, we conclude that extracellular antibiotic resistance genes (ARGs) should receive more attention and focus in the control of the propagation of ARGs. The abundances of ARO and MRO in tilapia pond water increased significantly; thus, the aquaculture water of tilapia farming should be treated effectively before discharge to reduce ARO and MRO contamination in the receiving environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Given the widespread use of commercial probiotics in aquaculture, it is important to evaluate the quality and environmental effects of these additives. Here, the effects of a Bacillus probiotic compound, BG4, on Penaeus vannamei survival rate, water quality factors, and microbial communities were assessed. An analysis of the BG4 powder confirmed the content of probiotic bacteria: 50.2% Bacillus licheniformis, 48.4% Bacillus subtilis, and 1.4% Bacillus amyloliquefaciens, consistent with the information on the product packaging. The effective bacterial quantity (1.1 × 109 CFU/g) was higher than that indicated on the product label (2 × 108 CFU/g). BG4 was added to a sterilized aquaculture water system, according to the indicated bacterial quantity; after 7 days, the maximum ammonia nitrogen, phosphate, and chemical oxygen demand degradation rates were 36.3%, 28.9%, and 15.2%, respectively. In the shrimp culture experiment, the survival rate of P. vannamei and water quality did not differ significantly between the BG4 and control groups. The bacterial quantity and high-throughput sequencing results indicated that Bacillus content in BG4 group decreased continuously from 3.5 × 104 CFU/mL to 6.9 × 102 CFU/mL. To ensure the desired effect of probiotics in commercial aquaculture applications, additional quality evaluations and scientific assessments are needed. [ABSTRACT FROM AUTHOR]

This study examined the phylogenetic and metabolic features of microbial communities in Baisha Bay mariculture areas of Nan'ao Island, a mariculture base on the Chinese Guangdong coast. Large seaweed ( Gracilaria lemaneiformis) cultivation zones (LZ), fish culture zones (FZ), and control zones (CZ) were sampled. According to community-level physiological profiling, d-mannitol, d-mannitol/α- d-lactose, and d-mannitol/α-cyclodextrin were the carbon sources with the highest utilization rates in CZ, LZ, and FZ, respectively ( R > 1.9). Denaturing gradient gel electrophoresis analysis showed that the dominant bacteria in CZ and LZ were Alphaproteobacteria (39.9 and 34.5%, respectively), whereas in FZ they were Flavobacteria (32.2%). The Shannon diversity in CZ and LZ was significantly higher than in FZ ( P < 0.05). Some opportunistic pathogens, such as Vibrio, Pseudoalteromonas and Loktanella, were abundant in FZ. The microbial communities and most of the dominant bacteria in FZ were more affected by environmental factors including salinity, chemical oxygen demand and total phosphorus. Some bacteria, such as Brevundimonas and Polaribater, have the potential to degrade agar in seaweed, and were isolated from samples rich in algae which are dominant in LZ. The cultivation of G. lemaneiformis created the notable structures and functions of macroalgae-associated bacterial communities that were less affected by the environmental factors examined. [ABSTRACT FROM AUTHOR]

A novel type of biochar was produced by mixing bamboo sawdust with sewage sludge (1:1, w/w) via a co-pyrolysis process at 400–600 °C. Changes in physico-chemical properties and the intrinsic speciation of metals were investigated before and after pyrolysis. Co-pyrolysis resulted in a lower biochar yield but a higher C content in the end product compared with use of sludge alone as the raw material. FT-IR analysis indicates that phosphine derivatives containing P H bonds were formed in the co-pyrolyzed biochars. In addition, co-pyrolysis of sludge with bamboo sawdust transformed the potentially toxic metals in the sludge into more stable fractions, leading to a considerable decrease in their direct toxicity and bioavailability in the co-pyrolyzed biochar. In conclusion, the co-pyrolysis technology provides a feasible method for the safe disposal of metal-contaminated sewage sludge in an attempt to minimize the environmental risk from potentially toxic metals after land application. [ABSTRACT FROM AUTHOR]

A green preparation method of castor oil lubricant additive was proposed. Functionalized graphene oxide (LP-GO) was rapidly and successfully prepared using a microwave-assisted ball milling device. LP-GO could be stably dispersed in castor oil for more than 80 days, and it could effectively improve the thermal conductivity and tribological properties of castor oil. [Display omitted] • LP-GO was prepared quickly and greenly using the microwave-assisted ball milling device. • LP-GO has excellent lipophilicity and can remain stably dispersed in castor oil for over 80 days. • LP-GO significantly improved the thermal conductivity and tribological properties of castor oil. • LP-GO in castor oil was investigated for its dispersion and lubrication mechanism. The realization of industrial applications of plant-based lubricants depends on well-dispersed lubricant additives. Herein, microwave-assisted ball milling directly grafted L-phenylalanine (LP) onto graphene oxide. The reaction does not require a pretreatment step and avoids high temperatures and catalyst involvement. The prepared LP-functionalized graphene oxide (LP-GO) exhibited hydrophobicity with a water contact angle of up to 133° and could maintain stable dispersion in castor oil for more than 80 days. 0.2 wt% of LP-GO improved the thermal conductivity of castor oil by 11.1 % and contributed to the enhancement of tribological performance under three different conditions. In particular, wear and friction decreased by 7.31 % and 11.54 % under the medium speed medium load condition, respectively. The friction decreased by 25.27 % in the low-speed high-load condition, and the wear decreased by 18.65 % under the high-speed low-load condition. The characterization of the tribological interface revealed that the lubrication mechanism of LP-GO was attributed to its protective and repairing effects at the friction interface. The surface functionalization approach in this paper is rapid and green. It can be extended to other functionalizing agents and nanomaterials, facilitating further applications of vegetable oils in tribology. [ABSTRACT FROM AUTHOR]

This study investigated the spatiotemporal dynamics, bioaccumulation, and critical influencing factors of antibiotics in tilapia aquaculture, focusing on source identification and environmental fate within typical farming systems. The results revealed a progressive increase in antibiotic concentrations in pond water and sediments over the cultivation period, with suspended solids and chemical oxygen demand identified as significant environmental factors influencing the distribution and dissemination of antibiotics. The aquaculture water source was the primary contributor of antibiotics in the farming system. Furthermore, the bioaccumulation factor (BAF) calculations indicated varying degrees of antibiotic enrichment in tilapia tissues, with sulfadimethoxine exhibiting the highest BAFs. Correlation analyses, redundancy analysis, and multivariate linear regression analysis provided insights into the relationship between environmental factors and antibiotics, identifying key antibiotics and influencing factors. The study highlighted the importance of managing and treating water sources to reduce the inflow of antibiotics into aquaculture systems and emphasized the need for non-antibiotic aquaculture practices to minimize the impact on the environment and public health. In conclusion, this research contributes valuable information for the development of effective management strategies and policies aimed at curbing antibiotic pollution in aquaculture environments, ensuring the sustainability of the aquaculture industry, and protecting ecosystem and consumer health. [Display omitted] • This study delves into the spatiotemporal dynamics of antibiotics in tilapia aquaculture. • Suspended solids and chemical oxygen demand emerge as significant environmental factors. • Aquaculture water source was the primary contributor of antibiotics in the farming system. • Bioaccumulation factors reveal varying degrees of antibiotic enrichment in tilapia tissues. [ABSTRACT FROM AUTHOR]

Sthenoteuthis oualaniensis is an important biological resource in the South China Sea. However, the microbiological characteristics of this squid, especially those of the dwarf-form, are poorly understood. This study was conducted to analyze the microbial community structure and metabolic characteristics of the intestinal and gill tissues of dwarf-form populations of S. oualaniensis. The dwarf-form squids of different sexes and gonadal maturities were collected from South China Sea in spring 2020. Results showed that Mycoplasma was the most dominant group of bacteria in the intestinal samples of the females with immature gonads (FN), females at sexual maturity (FY), and males at sexual maturity (MY) and the second-highest relative abundance group in males with immature gonads (MN). The microbial community structure in squid gills differed from that of intestinal flora. The BD1-7 clade was the dominant genus in gill samples of all groups. Furthermore, the microbial community activities in gills were higher than in intestinal groups, especially FYG. The larger dwarf-form populations had microbial communities with more robust utilization of carbon sources, assessed via average well color development (AWCD). Correlation and redundancy analysis determined that AWCD significantly positively correlated with the relative abundance of BD1-7 clade (p < 0.05). The results indicated that the dominant group of bacteria and microbial community structure were different between the intestinal and gill microbial communities in the dwarf-form S. oualaniensis populations of different sexes and maturities. Moreover, the metabolic potential of the gill microbial community was higher than that of the intestinal microbial community in the dwarf-form populations. [ABSTRACT FROM AUTHOR]

Biofloc technology (BFT) is a microbial biotechnology that has shown great potential in water quality control and nutrient re-utilization towards sustainable aquaculture. Carbohydrate addition is the main operation means for the application of BFT; however, we are still unclear how it affects microbial-driven nitrogen (N) transformation and utilization in BFT systems. In this study, autotrophic- and heterotrophic-dominated BFT systems (AS vs. HS) in triplicates were operated by two molasses addition strategies for a 13-week production trial of P. vannamei. Throughout the trial, more amount of bioflocs (in terms of VSS) were produced in HS than in AS. Higher concentrations of NH 4 +-N, NO 2 −-N, NO 3 −-N, TIN and TN while lower concentrations of TON were monitored in AS compared to HS. N budget analysis showed that the harvested shrimp deposited >34.4% of input N; and higher N retention in the final culture water while lower N loss and N discharge from the systems were found in AS compared to HS. Higher efficiencies of gross and feed N utilization were achieved in HS (36.6% and 38.8%) than in AS (34.5% and 34.9%). Metagenomic analysis revealed that abundant and diverse N-cycling microbial communities and functional genes in bioflocs constituted a complete and complex N-cycling network, which was the driving force of N transformation and recycling in the culture water of systems. The lower abundances of nitrifying bacteria and associated genes led to the inhibition of nitrification under high molasses addition in HS, which accounted for the differences in N dynamics, budget and utilization efficiency between AS and HS. Together, a quantitative model of N migration and transformation driven by N-cycling microbial communities of bioflocs was depicted in closed BFT systems for shrimp aquaculture. This study firstly revealed the N-cycling microbiome and functional effects in BFT systems, which provides theoretical and technical foundations for efficient N management in intensive aquaculture. [Display omitted] • Molasses addition generated auto- and hetero-trophic BFT systems for shrimp culture. • Molasses addition altered biofloc development, N dynamics and budget of BFT system. • N-cycling microbiome of biofloc was driving source of N-transformation in BFT system. • High molasses addition improved N utilization by inhibiting nitrification of BFT system. • Model of N migration and transformation pathway was established in closed BFT system. [ABSTRACT FROM AUTHOR]

In this work, the microstructure and subsurface hardness of pure Zr and Zr- x Fe (x = 0.2, 0.4, 0.6) model alloys were investigated at elevated temperatures (298–573 K) by means of scanning electron microscopy-electron backscatter diffraction (SEM-EBSD) analysis, transmission electron microscope (TEM) and high temperature nano-indentation test (HTNIT). Corresponding experimental results indicated that the addition of Fe element could lead to grain refinement for Zr–Fe alloys, and facilitate the formation of second phase particles (SPPs) like Zr 3 Fe precipitates and spherical particles in the matrix, which were in a close relationship with materials hardening. In order to address the hardness-indentation depth relation of Zr–Fe alloys with temperature effect, a mechanistic model was developed that covered the hardening mechanisms of lattice friction, precipitation hardening and dislocation interaction. Related theoretical analysis showed that all the three hardening mechanisms got weakened at high temperatures, which led to the decrease of materials hardness with increasing temperature. Moreover, the noticeable indentation size effect (ISE) was dominated by the formation of geometrically necessary dislocations (GNDs), and increasing temperature could result in the density decrease of GNDs due to the expansion of the plastic zone at elevated temperatures. With the increase of the indentation depth, the dominant hardening mechanism changed from the contribution of GNDs to that of statistically stored dislocations (SSDs). The results obtained in this work can help comprehend the effect of Fe element on both the microstructure and mechanical properties of Zr–Fe alloys at high temperatures. • High temperature nano-indentation is performed for Zr and Zr–Fe alloys. • Addition of Fe element in pure Zr can lead to grain refinement for Zr–Fe alloys. • A mechanistic model is developed for the hardness-depth relations of Zr–Fe alloys. • Theoretical results match well with experimental data at different temperatures. [ABSTRACT FROM AUTHOR]

• Dynamic changes of autophagy in the tMCAO mice within 7 d. • Autophagy was strengthened at 1 d of tMCAO induction, and then weakened steadily at 3 d, 5 d and 7 d. • Autophagy positively correlated with the inflammatory response and oxidative stress at 7 d after tMCAO. Ischaemic stroke is attributable to cerebrovascular disease and is associated with high morbidity, disability, mortality and recurrence. Autophagy is a critical mediator and plays dual roles in ischaemic stroke. Autophagy can protect against ischaemic brain injury during the early stage of ischaemic stroke, while excessive autophagy can induce apoptosis and exacerbate brain injury. However, the time-dependent variations in autophagy in ischaemic stroke are unknown. C57BL/6 mice were used to establish a model of temporary middle cerebral artery occlusion and reperfusion (tMCAO). The neurological functional scores and infarct volumes were determined at 1 d, 3 d, 5 d, and 7 d after modelling. The levels of Beclin-1, LC3B, p62, GFAP, TNF-α, IL-6, IL-10, ROS, 4-HNE and 8-OHDG were measured by ELISA, RT-PCR, immunofluorescence analysis and western blotting. The morphology of autophagosomes of ischaemic penumbra was observed by transmission electron microscopy (TEM). Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels increased (P < 0.01), while p62 and IL-10 levels decreased (P < 0.01) after tMCAO compared to those in the sham group. Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels were reduced in tMCAO mice at 3 d, 5 d and 7 d (P<0.05), and p62 and IL-10 levels were enhanced (P < 0.05) compared to those at 1 d. In addition, Beclin-1 positively correlated with LC3B, GFAP, TNF-α, IL-6, ROS, 4-HNE and 8-OHDG (P < 0.05), and Beclin-1 negatively correlated with p62 and IL-10 (P < 0.05). The number of autophagosomes was consistent with the expression of autophagy marker proteins, both showing a steady decrease. In summary, autophagy was activated within 7 d of tMCAO induction, and it strengthened at 1 d and then weakened steadily from 3 to 7 d. In addition, this study verified that autophagy positively correlated with the inflammatory response and oxidative stress at 7 d after tMCAO. [ABSTRACT FROM AUTHOR]

As being radiation-free, portable, and capable of repetitive use, ultrasonography is playing an important role in diagnosing and evaluating the COVID-19 Pneumonia (PN) in this epidemic. By virtue of lung ultrasound scores (LUSS), lung ultrasound (LUS) was used to estimate the excessive lung fluid that is an important clinical manifestation of COVID-19 PN, with high sensitivity and specificity. However, as a qualitative method, LUSS suffered from large interobserver variations and requirement for experienced clinicians. Considering this limitation, we developed a quantitative and automatic lung ultrasound scoring system for evaluating the COVID-19 PN. A total of 1527 ultrasound images prospectively collected from 31 COVID-19 PN patients with different clinical conditions were evaluated and scored with LUSS by experienced clinicians. All images were processed via a series of computer-aided analysis, including curve-to-linear conversion, pleural line detection, region-of-interest (ROI) selection, and feature extraction. A collection of 28 features extracted from the ROI was specifically defined for mimicking the LUSS. Multilayer fully connected neural networks, support vector machines, and decision trees were developed for scoring LUS images using the fivefold cross validation. The model with $128\times256$ two fully connected layers gave the best accuracy of 87%. It is concluded that the proposed method could assess the ultrasound images by assigning LUSS automatically with high accuracy, potentially applicable to the clinics. [ABSTRACT FROM AUTHOR]

Gamma-aminobutyric acid (GABA), an important bioactive compound, is synthesized through the decarboxylation of L-glutamate (L-Glu) by glutamate decarboxylase (GAD). The use of lactic acid bacteria (LAB) as catalysts opens interesting avenues for the biosynthesis of food-grade GABA. However, a key obstacle involved in the improvement of GABA production is how to resolve the discrepancy of optimal pH between the intracellular GAD activity and cell growth. In this work, a potential GAD candidate (LpGadB) from Lactobacillus plantarum was heterologously expressed in Escherichia coli. Recombinant LpGadB existed as a homodimer under the native conditions with a molecular mass of 109.6 kDa and exhibited maximal activity at 40°C and pH 5.0. The Km value and catalytic efficiency (kcat/Km) of LpGadB for L-Glu was 21.33 mM and 1.19 mM−1s−1, respectively, with the specific activity of 26.67 μM/min/mg protein. Subsequently, four C-terminally truncated LpGadB mutants (GadBΔC10, GadBΔC11, GadBΔC12, GadBΔC13) were constructed based on homology modeling. Among them, the mutant GadBΔC11 with highest catalytic activity at near-neutral pH values was selected. In further, the GadBΔC11 and Glu/GABA antiporter (GadC) of Lactococcus lactis were co-overexpressed in the host L. lactis NZ3900. Finally, after 48 h of batch fermentation, the engineered strain L. lactis NZ3900/pNZ8149-gadBΔC11C yielded GABA concentration up to 33.52 g/L by applying a two-stage pH control strategy. Remarkably, this is the highest yield obtained to date for GABA from fermentation with L. lactis as a microbial cell factory. Key points • The GadB from L. plantarum was heterologously expressed in E. coli and biochemically characterized. • Deletion of the C-plug in GadB shifted its pH-dependent activity toward a higher pH. • Reconstructing the GAD system of L. lactis is an effective approach for improving its GABA production. [ABSTRACT FROM AUTHOR]

In recent years, the propagation of antibiotic resistance genes (ARGs) and increased antibiotic resistance in pathogens have gained serious attention. Numerous reports have investigated the influence of domestic sewage discharge, medical wastewater and aquaculture wastewater on rivers and lakes, while the dynamics of ARGs in seawater and the relationships between ARGs, bacterial community structure and environmental factors have been less thoroughly described. In this study, the abundance, distribution and source of ARGs, as well as the relationships between ARGs, bacterial community changes and environmental factors in the seawater environment and sediment of Dapeng Cove, were investigated. Real-time quantitative PCR and Illumina Miseq sequencing technology were applied to determine the effects of the production cycle of cage culture, tourism and seasonality on ARGs. Chloramphenicol resistance genes (floR , cmlA) and sulfonamide resistance genes (sul1) were the dominant resistance genes in water and sediment. Pearson's correlation analysis showed that the abundance of all ARGs and the integrase I gene intI1 was positively correlated with chemical oxygen demand and suspended solids. Class 1 integrons might facilitate the dissemination of ARGs, and intI1 was detected in all samples at high concentrations. In aqueous environments, Cyanobacteria, Proteobacteria and Bacteroidetes were the dominant phyla, among which Proteobacteria and Bacteroidetes were positively correlated with the concentration of target ARGs. In the sediment, Proteobacteria, Bacteroidetes, Chloroflexi, Acidobacteria and Planctomycetes were the dominant phyla, among which Bacteroidetes and Planctomycetes were positively correlated with most of the target ARGs and had a significant influence on changes in the abundance of ARGs. The domestic sewage was the main source of ARGs in the seawater. Our results showed that bacterial community structure and environmental factors affected the distributional dynamics of ARGs. Anthropogenic activities played significant roles in promoting ARGs abundance in the seawater environments. Unlabelled Image • Sul1 , cmlA , and floR were the predominant ARGs in seawater and sediment samples. • COD and SS were positively correlated with all target ARGs. • IntI1 was detected in all samples at high abundance. • Proteobacteria, Bacteroidetes and Planctomycetes were the dominated phyla promoting ARGs dissemination. • Sewage discharge was the main source of ARGs in the Dapeng Cove seawater environment. [ABSTRACT FROM AUTHOR]

Intensive and semi-intensive aquaculture systems typically produce high loads of nutrients in their discharge, potentially leading to the development and persistence of harmful algal blooms (HABs). Algicidal bacteria, which inhibit algal growth or kill algal cells, offer a promising biocontrol strategy for reducing HAB. The strain JZBC1, which displays strong algicidal activity against the HAB species Scrippsiella trochoidea, was previously isolated from a dinoflagellate bloom area and identified as Bacillus cereus. In this study, strain JZBC1 was fermented in 2 L and 50 L systems, and then, algicidal properties of JZBC1 fermentation products on the harmful dinoflagellate species S. trochoidea, Prorocentrum micans, and Peridinium umbonatum were examined. Bacterial concentrations of strain JZBC1 reached 6.23 × 109 and 4.47 × 109 CFU/mL in 2 L and 50 L cultures, respectively, and thus effectively expanded during fermentation. Strain JZBC1 showed substantial algicidal activities and a wide algicidal range toward harmful dinoflagellates. Vegetative JZBC1 cells exhibited the best inhibitory and algicidal effects in 1 day. Strain JZBC1 can be formulated into a powder, and the spores can be activated before field application to increase their efficacy. These findings will facilitate large-scale fermentation production and application of Bacillus strain JZBC1 for controlling dinoflagellate blooms in aquaculture ponds. [ABSTRACT FROM AUTHOR]

Although the prevalence and concentrations of antibiotic resistance genes (ARGs) in aquaculture is receiving increasing scientific interest, there is little understanding of the direct sources and dissemination pathways of ARGs in marine aquaculture-reared organisms. This study investigated the dynamics of ARGs and the bacterial community throughout the rearing period in a typical marine aquaculture farm in South China. The results demonstrated that sul1 and qnrD were predominant in the sediment, and qnrD and qnrA were predominant in the intestinal tracts of shrimps. Network analysis showed that the chemical oxygen demand, total organic carbon, dissolved organic carbon, suspended solids, and total phosphorus were positively correlated with the predominant ARGs. The results of the network and source tracking analyses indicate that environmental factors and the bacterial community may drive the dissemination of ARGs dissemination in the environment and in shrimp reared by marine aquaculture, and sediment is the most direct and important medium in this dissemination. These results aid in improving our understanding of the sources, level, and dissemination of ARGs in marine aquaculture. [ABSTRACT FROM AUTHOR]

Abstract In recent years, cyanobacterial blooms occur with increasing frequency during the process of aquaculture. They could cause damage on aquaculture systems and bring huge economic losses. It is necessary to develop effective and ecofriendly methods to control cyanobacterial blooms. In this study, a 56-day field experiment was conducted to assess the effects of algicidal bacterium CZBC1 (group B) and its combined use with molasses (group BC) against a cyanobacterial bloom in Litopenaeus vannamei culture systems. During the experimental period, the densities of Oscillatoria and microalgae decreased gradually in groups B and BC, and both percentages of Oscillatoria in microalgae decreased significantly to <4% at the end of the experiment. Meanwhile, the densities of total bacteria and cultivable heterotrophic bacteria increased faster in groups B and BC compared with the control group. The result from 16S rRNA high-throughput sequencing showed that the relative abundance of the Cyanobacteria phylum and the Oscillatoriophycideae class in groups B and BC decreased to very low levels, and the phyla of Proteobacteria and Bacteroidetes were more abundant in group BC after 7 days. The bacterial richness (Chao1 and ACE) increased gradually in all experimental groups, while the addition of molasses appeared to have some effects on α-diversity (Shannon and Simpson indices) of bacterial community. Furthermore, the peak concentrations of total ammonia nitrogen and nitrite-nitrogen were found to be significantly lower in groups B and BC compared with the control group, and molasses significantly promoted the increase of total suspended solids concentration. Consequently, survival, final weight, growth rate and feed conversion rate of cultured shrimp were improved in groups B and BC. Notably, a synergistic effect could be found when CZBC1 and molasses were used in combination for cyanobacteria control. The results of this study indicate a promising practical method for cyanobacteria control in aquaculture systems. Highlights • CZBC1 and molasses could be used for cyanobacteria control in shrimp culture systems. • The density and percentage of Oscillatoria could be decreased by addition of CZBC1. • The relative abundance of Cyanobacteria decreased to a low level by addition of CZBC1. • Water quality and shrimp performance could be improved by addition of CZBC1. • Synergistic effects could be found when CZBC1 was used in combination with molasses. [ABSTRACT FROM AUTHOR]

Although research regarding antibiotic resistance genes (ARGs) in aquaculture environments has gained increasing scientific interest, further studies are required to understand the abundances and removal mechanisms of ARGs during the entire rearing period of shrimp aquaculture. Thus, in this study, abundances, distributions and removal rates of ARGs in different environmental compartments of intensive shrimp farms in South China were investigated during the entire rearing period. The results indicated that sul1 and cmlA were the predominant ARGs in the water and sediment samples. Additionally, the total abundance of ARGs was higher in shrimp pond water than in the source water and farm effluent. Moreover, sediment samples indicated significantly higher ARG abundances than water samples from the shrimp ponds (P < 0.05). Environmental factors were found to significantly affect the distribution of ARGs in shrimp rearing environments. Furthermore, stable ponds aided the removal of ARGs from shrimp pond water. This study accounted for temporal variations in ARG abundances as well as removal of ARGs in different environmental compartments during the entire shrimp rearing period. However, additional research is required to optimize the water treatment process for removal of ARGs from the aquaculture. [ABSTRACT FROM AUTHOR]

The surface functionalization of metal and metal oxide nanoparticles (NPs) is reviewed systematically, highlighting their dispersion and tribological applications. The outlines of the synthesis and surface functionalization strategies of metal and metal oxide NPs are presented. The dispersibility test methods and tribological applications of metal and metal oxide NPs are discussed. Possible future research hotspots and challenges in the field are suggested. [Display omitted] • The existing synthetic methods and surface functionalization strategies for metal and metal oxide nanoparticles (NPs) were outlined. • The dispersion evaluation methods and tribological studies of metal and metal oxide NPs were reviewed. • The effects and potential mechanisms of surface functionalization on the metal and metal oxide NPs in lubricating media were evaluated. • Challenges in the field were discussed and possible hot spots for future research are suggested. Friction has caused a substantial amount of property damage in many industries worldwide, and the continuous progress of industrial production requires the development of high-performance lubricants. The performance of lubricants largely depends on the additives in their formulation. Notably, metal and metal oxide nanoparticles (NPs) have been widely used to improve lubricants and have shown great potential. However, their efficacies as lubricant additives are limited due to their high surface energy, as well tendency to aggregate, agglomerate, and coagulate in lubricating media. Owing to these concerns, researchers have focused on tunable surface functionalization of metal and metal oxide NPs. Surface functionalization has been demonstrated as an effective way to improve the performance of such NPs as reinforcing phases and lubricant additives in composites. Therefore, this article provides a systematic review of the current research status on the surface functionalization of metal and metal oxide NPs, which has not been comprehensively reviewed yet. To begin with, we outline the existing synthesis methods of metal and metal oxide NPs and discuss the existing surface functionalization strategies. Following, we review the dispersion evaluation methods and tribological studies of metal and metal oxide NPs. Subsequently, we also assess the impact of surface functionalization strategies on the dispersion and tribological performance of metal and metal oxide NPs, as well as their underlying mechanisms. Finally, we discuss the existing challenges and suggest potential future research directions. We anticipate that this article could serve as an excellent guide for the chemical functionalization of metal and metal oxide NPs, which could be beneficial for various applications such as tribology, thus opening up a pathway to improve the physical and chemical properties of metal and metal oxide NPs. [ABSTRACT FROM AUTHOR]

Ecological treatment system (ETS) has been recognized as a promising technology for mitigating agricultural non-point pollution, whereas it remains to be seen how nitrogen (N) forms and bacterial communities in ETS sediments respond to different aquatic N conditions. Therefore, a four-month microcosm experiment was conducted to investigate the effects of three aquatic N conditions (2 mg/L NH 4 +-N, 2 mg/L NO 3 −-N and 1 mg/L NH 4 +-N + 1 mg/L NO 3 −-N) on sediment N forms and bacterial communities in three ETSs vegetated by Potamogeton malaianus , Vallisneria natans and artificial aquatic plant, respectively. Through analysis of four transferable N fractions, the valence states of N in ion-exchange and weak acid extractable fractions were found to be mainly determined by aquatic N conditions, while significant N accumulation was observed only in strong oxidant extractable and strong alkali extractable fractions. Sediment N profiles were primarily influenced by time and plant types, with N condition having secondary effect, while sediment bacterial community structures experienced a significant shift over time and were slightly influenced by plant types. Sediment functional genes related to N fixation, nitrification, assimilable nitrate reduction, dissimilatory nitrite reduction (DNRA) and denitrification were substantially enriched in month 4, and the bacterial co-occurrence network exhibited less complexity but more stability under NO 3 − condition compared to others. Furthermore, certain sediment N fractions were found to have strong relationships with specific sediment bacteria, such as nitrifiers, denitrifiers and DNRA bacteria. Our findings highlight the significant influence of aquatic N condition in submerged macrophyte-type ETSs on sediment N forms and bacterial communities. [Display omitted] • Aquatic N condition significantly influenced the unstable N fractions in sediments. • N accumulation only happened in the stable N fractions in sediments. • Aquatic N altered the structure and function of sediment bacterial community. • N cycling bacteria and transferable N profile were strongly correlated in sediments. [ABSTRACT FROM AUTHOR]

Highlights • Complexation of Hg with the antibiotics resulting in the dissolution of Hg compounds from the sediment. • Hg ions in the sediment can also promote the degradation of antibiotics. • The degradation of TC/OTC radicals generates CH3+ groups which can react with Hg° to form MeHg. Abstract The role of antibiotics commonly used in fish culture activities in methylmercury (MeHg) formation in mariculture sediments (MS) and in reference sediments (RS) was studied using simulation microcosms. MS and RS were split into three equal batches. Two batches were spiked with Hg(NO 3) 2 aqueous solution at levels of 2 and 8 mg kg−1 (dry weight basis) and the remainder served as a control batch. Tetracycline (TC) and oxytetracycline (OTC) (2.5 g and 10 g of each) were added to each treatment. Sediment THg concentration decreased during the culture period possibly due to complexation of Hg with the antibiotics resulting in the dissolution of Hg compounds from the sediment. More importantly, the MeHg concentration increased after 32 days together with a decrease in the concentrations of the antibiotics in the sediment. The complexation of TC or OTC with Hg resulted in the transport of electrons from TC or OTC to Hg2+ due to the high electronegativity of Hg2+. Subsequently, Hg2+ was reduced to Hg° which reacted with CH 3 + derived from TC or OTC. The use of antibiotics may therefore promote the formation of MeHg in sediments. [ABSTRACT FROM AUTHOR]

Abstract More attention has been paid to the abundance and diversity of antibiotic resistance genes (ARGs) in aquatic environments. However, few studies have investigated the persistence and spatial variation of ARGs in aquatic organisms. This study investigated the occurrence and abundance of ARGs and the bacterial populations in shrimp intestinal tracts during the rearing period in different regions of Guangdong, South China. The results showed that sul 1, sul 2, qnr D, and flo R were the predominant ARGs. Compared with those of juvenile shrimp, the total concentrations of ARGs in the intestinal tract of adult shrimp in three shrimp farms were 2.45–3.92 times higher (p < 0.05), and the bacterial populations in the adult shrimp intestinal tract changed considerably. Redundancy analysis (RDA) showed that the abundance of Proteobacteria, Firmicutes, and Verrucomicrobia in Farms A, B, and C, respectively, were strongly positively correlated with the most abundant and predominant genes (sul 1 and qnr D for Farm A; flo R and sul 2 for Farm B; flo R and sul 2 for Farm C) in the shrimp intestinal tract. The results of this study indicated that ARGs gained persistence in the developmental stages of the reared shrimp. Different phyla of predominant bacteria were responsible for the increase of ARGs abundance in the shrimp intestinal tract in different regions. This study represents a case study of the persistence and spatial variation of ARGs in aquaculture and can be a reference for the determination of harmful impacts of ARGs on food safety and human health. Highlights • Sul 1, sul 2, qnr D, and flo R were the predominant ARGs in shrimp intestinal tract. • Bacterial population in shrimp intestinal tract changed considerably. • ARGs gained persistence in the developmental stages of the reared shrimp. • Spatial variation of ARGs and bacterial population were found in shrimp aquaculture. [ABSTRACT FROM AUTHOR]

Highlights • The transformation of PTEs in sewage sludge hydrochars was studied. • Effects of phosphoric acid activation on immobilization of PTEs were explored. • H 3 PO 4 in feed-water deactivated PTEs to reduce the sludge environmental risk. • High aromaticity caused high residual rates of PTEs in the hydrochars. • Large numbers of phosphate minerals effectively occluded PTEs in the hydrochars. Abstract The effect of phosphoric acid addition to the feed-water on the speciation and transformation behaviour of potentially toxic elements (PTEs) in the hydrothermal carbonisation (HTC) of sewage sludge was explored. Over 70% of each of the PTEs (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) was in the directly bioavailable and potentially bioavailable fraction in the raw sludge, and especially Cu and Zn at 97.5 and 98.6%, respectively. Through the HTC process the directly bioavailable and potentially bioavailable fractions of PTEs in the sludge hydrochar clearly decreased, and the residual fraction in the hydrochar showed an observable increase. Further stabilisation of PTEs in hydrochar occurred during HTC with the addition of phosphoric acid solution to the feed-water. As the concentration of phosphoric acid in the feed-water increased the percentages of the residual fraction of Cd, Cr, Ni, Pb and Zn in hydrochars each exceeded 80%, but different PTEs behaved differently with increasing phosphate molar ratio in the feed-water. When the molar ratio of phosphate was 15%, the percentages of the residual fractions of Cd, Mn and Zn reached their maximum values in accordance with the changing trend in aromaticity of the hydrochar. Moreover, a large number of phosphate mineral crystals effectively occluded the PTEs in hydrochar. In conclusion, the addition of phosphoric acid to the feed-water during HTC further deactivated PTEs leading to a substantial decline in the potential environmental risk associated with the land application of the sewage sludge. [ABSTRACT FROM AUTHOR]