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Red-emitting Ba 2 YSbO 6 :Eu3+ phosphors with double perovskite structure have been prepared by solid-state method. Phase structures, photoluminescence properties, and thermal stability performances have been investigated in detail. The prepared phosphors reveal a cubic phase with the space group of Fm-3m. They exhibit a doughty red emission band at 612 nm ascribed to the Eu3+:5D 0 →7F 2 transition under 393 and 465 nm excitation. The samples have high concentration quenching property with the optimal concentration reached to 70 mol%, deriving from the quadrupole-quadrupole interaction. Additionally, the Ba 2 YSbO 6 :Eu3+ phosphors demonstrate robust thermal performance with the emission intensity retaining 78.8% at 423 K of that at 303 K. Ultimately, the phosphor-converted LED device is fabricated by combining the red-emitting Ba 2 YSbO 6 :Eu3+ phosphor and YAG:Ce3+ yellow ones to a blue chip (460 nm), which exhibits a warm white light with color rendering index(CRI) of 80.8 and correlated color temperature (CCT) of 5184 K. [ABSTRACT FROM AUTHOR]

Four vanillic acid-degrading bacterial strains, named LR5S13T, LR5S20, and M4R5S39T and LN1S58, were isolated from Kalidium cuspidatum rhizosphere and bulk soils, respectively. Phylogenetic analysis based on 16S rRNA gene as well as core genome revealed that LR5S13T and LR5S20 clustered closely with each other and with Halomonas ventosae Al12T, and that the two strains shared the highest similarities (both 99.3 %) with H. ventosae Al12T, in contrast, M4R5S39T and LN1S58 clustered together and with Halomonas heilongjiangensis 9–2T, and the two strains shared the highest similarities (99.4 and 99.2 %, respectively) with H. heilongjiangensis 9–2T. The average nucleotides identities based on BLAST (ANIb) and digital DNA-DNA hybridization (dDDH) values of strains LR5S13T to LR5S20, and M4R5S39T to LN1S58, were both higher than the threshold values for delineation of a species. The ANIb and dDDH values of the four strains to their closely relatives were lower than the threshold values. All four strains take phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol as the major polar lipids, Summed Feature 8, Summed Feature 3, and C 16:0 as the major fatty acids. Based on the phylogenetic and phenotypic results, the four strains should be classified as two novel Halomonas species. Therefore, Halomonas rhizosphaerae sp. nov. (type strain LR5S13T = KCTC 8016T = CGMCC 1.62049T) and Halomonas kalidii (type strain M4R5S39T = KCTC 8015T = CGMCC 1.62047T) are proposed. The geographical distribution analysis based on 16S rRNA gene revealed that the two novel species are widely distributed across the globe, specifically in highly saline habits, especially in Central and Eastern Asia. [ABSTRACT FROM AUTHOR]

Highlights • Diffuse-interface simulation of bubble dynamics in a binary mixture is performed. • Local accumulation of gas with the bubble is critical to continuous bubble growth. • Strong thermocapillary flow peaks before bubble pinch-off from the biphilic surface. Abstract In this paper, we numerically study pool boiling of a binary (water and nitrogen) mixture on a surface endowed with a combination of hydrophobicity and hydrophilicity (i.e., the so called biphilic surface). Here we adopt a numerical approach based on the phase field theory, where the vapor-liquid interface is assumed to be of a finite thickness (hence diffusive in nature) and requires no explicit tracking schemes. The theoretical modeling of two-phase heat and mass transfer in water diluted with nitrogen demonstrates the significant impact of impurities on bubble dynamics. The simulations show that locally high concentrations of nitrogen gas within the vapor bubble is essential to weakening the condensation effect, which results in sustained bubble growth and ultimately (partial) departure from the surface under the artificially enlarged gravity. Simply increasing the solubility of nitrogen in water, however, turns out to be counterproductive because possible re-dissolution of the aggregated nitrogen by the bulk water could deprive the bubble of vital gas contents, leading instead to continuous bubble shrinkage and collapse. Additionally, it is found that with the significant accumulation of nitrogen, the bubble interface is increasingly dominated by a strong interfacial thermocapillary flow due to the Marangoni effect. [ABSTRACT FROM AUTHOR]

Highlights • Visualization is performed of bubble growth on a biphilic surface under low pressures. • Bubble departure diameter shows a mechanistic transition with decreasing pressures. • A simple predictive model demarcating the bubble contact line mobility is derived. Abstract Boiling suffers from inefficient intermittent cycles of bubble generation under subatmospheric conditions. Such deterioration in heat transfer rates can be alleviated but not completely eliminated by use of mixed-wettability (biphilic) surfaces. Here we study bubble dynamics on a single hydrophobic spot in low-pressure pool boiling. The results reveal an interesting transition in bubble departure behavior from the surface-driven mode to the drag-driven mode, which correlates closely with the dynamic state of the three-phase contact line on the surface. Based on the force-balance argument, a simple model is derived to map the contact-line mobility during bubble growth. It is found that below a certain threshold pressure, the bubble base expansion is increasingly likely to overcome the strong pinning of the contact line at the interface between the hydrophobic and hydrophilic regions. That could lead to total removal of vapor residues from the surface and cause deactivation of the nucleation site, which portends the eventual takeover of intermittent boiling on the biphilic surface. [ABSTRACT FROM AUTHOR]

• Enhanced ethanol boiling by combining surface texturing and wettability patterning. • Over-twofold higher heat transfer rates obtained on micro- and nanoporous surfaces. • Facilitated heterogeneous nucleation suggestive of a vital role by surface nanobubbles. Boiling of highly wetting fluids is of great interest to thermal management of high-powered electronic devices, enhancement of which conventionally relies on functional modifications of surface shape and structure so as to promote bubble generation and growth. In this paper we attempt to combine the approach of porous texturing with a novel technique of surface wettability engineering to enhance saturated pool boiling of ethanol. Thin layers of microporous and nanoporous surface topographies were chemically deposited on an aluminum substrate by anodization in phosphoric acid and sulfuric acid, respectively. Boiling on the textured surfaces recorded over-twofold increases in terms of the heat transfer coefficient compared with that on a plain smooth surface, which can be attributed to a proliferation of active nucleation sites. The boiling incipience point on both porous surfaces, however, exhibited an interesting dependence on the initial wetting state of the surface. With the application of amphiphobic coatings of fluoropolymer modified with halloysite nanotubes, we managed to engender a biphilic (i.e., spatially alternating hydrophobicity and hydrophilicity) pattern on the porous-textured surfaces. The repeat control experiments on the hybrid surfaces showed an equally efficient mode of nucleate boiling, whose inception, by contrast, seemed to occur at consistently low superheats. The remarkable reduction (by more than 80%) of the minimum superheat at the boiling onset hints at an alternative nanobubble-related mechanism for heterogeneous bubble nucleation, which is notably less affected by incondensable gas, to the classic vapor-trapping-cavity model. [ABSTRACT FROM AUTHOR]

• Bubble spreading behavior on biphilic surfaces varies with decreasing pressure. • Strong correlation exists between contact-line mobility and bubble growth dynamics. • Critical role of accelerated bubble growth in depinning contact line is confirmed. Surface wettability engineering has attracted growing attention in recent years as an effective tool to enhance boiling heat transfer. On wettability-patterned (so-called biphilic) surfaces in particular, subatmospheric boiling has been shown to be nearly free of the severe degradation of heat transfer rate that tends otherwise to prevail on plain surfaces. The surprisingly consistent performance under reduced-pressure conditions can be attributed to the rather strong pinning of the three-phase contact line (TPCL) at the border between the hydrophobic and hydrophilic surfaces, which essentially eliminates the waiting period between bubble cycles. Only when the pressure is decreased sufficiently low does the transition to the undesired mode of intermittent boiling eventually occur on the biphilic surface. The purpose of the present study is to investigate the physical mechanism for the heat transfer deterioration on a mixed-wettability surface at very low pressures. To that end, we performed high-speed visualization experiments of the process of bubble nucleation and growth on a smooth copper surface coated with a single hydrophobic polytetrafluoroethylene (PTFE) spot, under different surface superheats and system pressures. The results show an interesting correlation between the TPCL behavior and the bubble growth dynamics. Specifically, under some certain threshold of pressure, it would become increasingly likely for the TPCL to be dislodged from its pinned position on the biphilic surface under a particularly rapid bubble expansion. As a result, full flooding of the hydrophobic surface might ensue, which is deemed responsible for temporary deactivation of the hydrophobic spot as a viable nucleation site. Furthermore, based on the diffuse-interface simulations of TPCL propagation across heterogeneous wettabilities, a comparison of cases with different bubble expansion rates offered qualitative evidence supporting the critical role of such accelerated bubble growth rate in driving the TPCL to overcome the energy barrier raised at the wettability divide. [ABSTRACT FROM AUTHOR]

The rhizosphere is critical for interactions within the plant microbiome and serves as a key environment for the growth of bacteria that produce or resist antimicrobials. This environment facilitates the strengthening of antibiotic resistance genes (ARGs). Although applying antimicrobial-producing microorganisms helps to reduce the incidence of soil-borne diseases, little is known about their impact on ARG dynamics throughout the plant growth period. Rhizosphere soils from organic fertilizer (OF) and organic fertilizer + Bacillus amyloliquefaciens T-5 (OF + T5) from a long-term field trial were chosen to assess the ARG risk under the input of biocontrol agents during all stages of plant growth. Metagenomic sequencing was used to quantify the dynamics of ARGs, mobile genetic elements (MGEs), and microorganisms harboring these genetic elements. A microcosm pot experiment was then conducted in which tomato plants were cultivated with different concentrations of B. amyloliquefaciens (103, 105, 107, and 109 cells mL−1) to verify the results. The metagenomic data indicated that during the early stage of plant growth, the inoculated biocontrol agent, along with other stimulated beneficial microbes, such as Pseudomonas spp. and Streptomyces spp., which contain ARGs, increased the risk of ARG enrichment in the rhizosphere. However, as plant growth progressed and pathogenic bacteria surged, these beneficial microbes suppressed the increase in the abundance of Ralstonia solanacearum rich in ARGs. This, in turn, mitigated the ARG risks associated with the early-stage enrichment of functional microorganisms. This dynamic between beneficial microbes and plant pathogens in the rhizosphere represents a subtle yet crucial process in mitigating ARG risks. In summary, balancing the limited ARG risk posed by beneficial microorganisms with the prevention of the potentially unlimited ARG risks associated with pathogenic bacteria presents a promising approach within the "One Health" framework. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogel strain sensor is a robust candidate for electric skin (E-skin). In this paper, a highly stretchable and self-healing chitosan/polysulfobetaine (CS/PSBMA) double network (DN) hydrogel was prepared based on fully physically cross-linking to mimic the function of human skin. The CS network and the PSBMA network in CS/PSBMA DN hydrogel are crosslinked by ion chelation and hydrophobic interaction, respectively. The dynamic cross-linking allows the hydrogel network to reconstruct when damaged, providing the DN hydrogel with a stretchability of 1400% and an excellent self-healing efficiency as high as 91.1% after attaching together naturally at room temperature for 24 h. Moreover, the self-healing behavior of the CS/PSBMA DN hydrogel can repeat at least 7 times at the same incision site. Notably, the resistance of the CS/PSBMA DN hydrogel is sensitive to a wide strain range and the relative resistance exhibits stable and reliable changes during deformation. When used as a strain sensor, the CS/PSBMA DN hydrogel is capable of real-time detecting various human motions such as finger and throat movements. More importantly, the sensitivity and stability of the hydrogel sensor can be maintained after being damaged and self-healing. Therefore, the hydrogel sensor demonstrated here has a promising prospect as E-skin for motions detection and healthcare monitoring. Image 1 • A CS/PSBMA double network hydrogel was prepared by fully physically crosslinking. • The hydrogel has excellent stretchabily (1400%) and self-healing properties (91.1%). • The hydrogel has self-adhesive properties and good sensitivity to strains. [ABSTRACT FROM AUTHOR]

• An ionically and chemically crosslinked PHEAA/CS DN hydrogels with tunable mechanical properties was successfully prepared. • The hybrid DN hydrogels have high tensile strength (3.8 MPa), fast self-recovery ability and excellent fatigue resistance. • The destruction and reconstruction of the networks in DN hydrogel was proved and theorized. • The hybrid DN hydrogels have excellent antifouling and antibacterial properties called "repelling and killing" effect. Hydrogels with good mechanical properties are promising for various applications. In this work, a simple yet effective method for preparing a novel double-network hydrogel was reported. First, nonfouling polymer, poly(N- (2-hydroxyethyl)acrylamide) (PHEAA), was crosslinked through covalent bonds. Antibacterial polysaccharide, chitosan (CS), was then crosslinked by chelation between the N- glucosamine units on the CS and citrate or sulfate ions. The poly(N- (2-hydroxyethyl)acrylamide)/chitosan double-network hydrogels (PHEAA/CS DN hydrogels) exhibited high tensile strength (3.8 MPa), strong elastic modulus (0.6 MPa). And the dynamic ionic crosslinking in CS network provided the DN gels with fast self-recovery ability as well as excellent fatigue resistance. Furthermore, the mechanical properties of the DN gels were enhanced after stretching and relaxing because of the molecular orientation and reconstruction of chitosan network. More importantly, the hydrogels have excellent antifouling and antibacterial properties, which is called "repelling and killing", making them competitive candidates for applications in the biomedical field. [ABSTRACT FROM AUTHOR]

Soil microorganisms play an essential role in the redistribution of soil aggregate sizes due to the microenvironmental changes. Yet, little is known regarding how individual microbial taxa within different-sized aggregates respond to agronomic practice. This study integrated physical, chemical, and molecular techniques (i.e., high-throughput DNA sequencing and qPCR) to assess the influence of corn-tobacco rotation on the soil microbial community at the soil microenvironment scale, i.e., within mega- (>2 mm), macro- (0.25–2 mm) and micro-aggregate (<0.25 mm) fractions. The soil samples (0–20 cm) analyzed in this study originated from corn and tobacco, which were cultivated under three different fertilization regimes. The results demonstrate that corn-tobacco rotation substantially impacted the distribution of aggregate sizes, and the shift in soil microbial communities associated with soil aggregates was related to changes in soil total carbon (TC), the C/N ratio and pH. The indicator microbial taxa (i.e., those were sensitive to crop rotation) varied with aggregate size. When compared with tobacco soil, the corn soil showed higher relative abundances of probably more copiotrophic taxa across large-sized aggregates, also with more bacteria in mega-aggregates and more fungi in macro-aggregates. Changes in total microbial communities associated with mega- and macro-aggregates in response to crop rotation were driven mainly by alterations in bacterial and fungal communities, respectively. Overall, the results of this study demonstrate that soil aggregate size strongly affected the microbial community composition on agricultural fields, promoting the differential responses between bacteria and fungi to crop rotation in specific size of aggregates. [ABSTRACT FROM AUTHOR]

Abstract: Bacteria act as the dominant degraders during the composting process, although fungi also play important roles. In the present study, a 112-day aerobic composting by dairy manure and rice chaff was conducted. Four 16S rRNA gene clone libraries were constructed from samples taken at days 0, 12, 42 and 112, and a total of 779 randomly selected clones were sequenced. The coverage values calculated with the DOTUR program based on a 98% sequence similarity criterion ranged between 0.75 (day 112) and 0.94 (day 42). The results showed that the bacterial communities varied significantly during the composting process. Firmicutes and Proteobacteria were the two most abundant phyla at all stages. Bacteroidetes and Chloroflexi were ubiquitous. The phylum Actinobacteria was dominant only at the thermophilic stage (day 42). A slight increase in bacterial diversity at the phylum and genus levels was observed as the composting process progressed, but different results were obtained at the species level. Moreover, sequences belonging to the candidate phylum BCR1 were determined in this experiment. This study may provide a better understanding of the bacterial community composition and succession during the composting process. [Copyright &y& Elsevier]

Abstract: A thermophilic naphthalene- and aliphatic hydrocarbon-degrading bacterium SH-1 was isolated from a deep oil well and identified as Geobacillus sp. n-alkanes from C12 to C33 in crude oil and naphthalene were effectively degraded by strain SH-1, and this strain could readily utilize these compounds as its sole carbon and energy resources. During the degradation of naphthalene, strain SH-1 initiated its attack on naphthalene by a monooxygenation at its C-1 to give 1-naphthol and further monooxygenation at C-2 to produce 1,2-dihydroxynaphthalene. The ring of 1,2-dihydroxynaphthalene was cleaved to form trans-o-hydroxybenzylidenepyruvate. Subsequently, trans-o-hydroxybenzylidenepyruvate was transformed to (2E)-3-(2-hydroxyphenyl)prop-2-enal by losing a carboxyl group. Additionally, benzoic acid was identified as an intermediate in the naphthalene degradation pathway of this Geobacillus strain. This study highlights an important potential use of the thermophilic degradative strain SH-1 in the cleanup of environmental contamination by naphthalene and crude oil and presents a mechanism for naphthalene metabolism. [Copyright &y& Elsevier]

Abstract: A bacterial strain, J12, isolated from the rhizosphere soil of tomato plants strongly inhibited the growth of phytopathogenic bacteria Ralstonia solanacearum. Strain J12 was identified as Pseudomonas brassicacearum based on its 16S rRNA gene sequence. J12 could produce 2,4-diacetylphloroglucinol (2,4-DAPG), hydrogen cyanide (HCN), siderophore(s) and protease. The maximum growth and antagonistic activity were recorded at 30°C and pH 8. Glucose and tryptone were used as the most suitable carbon and nitrogen sources, respectively. Strain J12 significantly suppressed tomato bacteria wilt by 45.5% in the greenhouse experiment. The main antimicrobial compound of J12 was identified as 2,4-diacetylphloroglucinol (2,4-DAPG) by HPLC–ESI-MS analysis. The gene cluster phlACBD, which is responsible for 2,4-DAPG production, was identified and expressed in the bacterial strain Escherichia coli DH5α. [Copyright &y& Elsevier]

The assessment of maturity and biological parameters is important in the composting process. In this study, excitation–emission matrix (EEM) fluorescence spectroscopy was applied to evaluate the maturity and biological parameters of compost produced from the co-composting of dairy and rice chaff. The results from a Pearson correlation analysis between traditional physico-chemical maturity indices and fluorescence regional integration (FRI) parameters showed that among the FRI parameters, P V,n /P III,n and P V,n were suitable for the assessment of compost maturity. Moreover, the FRI parameters could be used to evaluate biological parameters including the germination index (GI) and ribotype evolution which indicate the bacterial community structure and dynamics. P IV,n was the most suitable indicator for revealing the community structure and dynamics during the composting process. Fluorescence spectroscopy combined with the FRI analysis could be used as a sensitive and efficient tool for assessing compost maturity and biological parameters. [ABSTRACT FROM AUTHOR]

Abstract: A Gram-negative coccus, strain 2B5, was isolated from the sea mud of the crude oil-polluted Donghai area in China and identified as Alcanivorax sp. based on its physiological characteristics and analysis of its 16S rRNA gene sequence. Strain 2B5 was able to degrade C13–C30 n-alkanes and branched alkanes (pristane and phytane) from crude oil as the sole carbon source. The optimal temperature and pH for strain 2B5 growth and octadecane degradation were 30–37°C and pH 6.0–7.0, respectively. NaCl is required for strain 2B5 growth and octadecane degradation were highest at NaCl concentrations of 20 to 90gL−1. A novel alkane hydroxylase gene (alkB), obtained by self-formed adaptor PCR (SEFA-PCR), displays 41.9% deduced amino acid sequence identity with alkB1 of Alcanivorax borkumensis SK2. Functional heterologous expression of the alkB gene was achieved in Pseudomonas fluorescens KOB2△1. Recombinant Pseudomonas containing the alkB gene of Alcanivorax sp. strain 2B5 recovered the ability to grow on C14 and C16 n-alkanes. RT-PCR analysis showed that expression of the alkB gene was induced by octadecane. There could be other alkane hydroxylases in Alcanivorax sp. 2B5 that could be involved in the degradation of short- and long-chain alkanes. [Copyright &y& Elsevier]

Abstract: An extremely thermophilic alkane-degrading bacterium, strain MH-1, was isolated from the deep subterranean petroleum reservoir in Shengli oil field, PR China. Based on its physiological characteristics and analysis of its 16S rRNA gene sequence, strain MH-1 was identified as Geobacillus stearothermophilus. Strain MH-1 was able to grow at temperatures ranging from 50 to 72°C and effectively degraded hexadecane as the sole carbon source at 70°C. Strain MH-1 degraded alkanes with different length chains (C12–C31) in crude oil, but it preferentially degraded middle chain-alkanes. The alkane hydroxylase system of G. stearothermophilus MH-1 was characterized. It contained at least three alkane monooxygenase gene homologs (alkB-geo1, alkB-geo4, and alkB-geo6). The AlkB-geo6 cluster, which had a high sequence similarity to the alkB2 cluster of Rhodococcus strains NRRL B-16531 and Q15, contained alkB-geo6, two rubredoxins and a putative transcriptional regulatory protein. [Copyright &y& Elsevier]

• AGCNs use Gabor filters to manipulate convolutional kernels. • We have proved that AGCNs can learn the invariant information from images. • The parameters in the Gabor filters can be updated during the model training. • We demonstrate the robustness of AGCNs against adversarial attacks. [Display omitted] Despite the great breakthroughs that deep convolutional neural networks (DCNNs) have achieved on image representation learning in recent years, they lack the ability to extract invariant information from images. On the other hand, several traditional feature extractors like Gabor filters are widely used for invariant information learning from images. In this paper, we propose a new class of DCNNs named adaptive Gabor convolutional networks (AGCNs). In the AGCNs, the convolutional kernels are adaptively multiplied by Gabor filters to construct the Gabor convolutional filters (GCFs), while the parameters in the Gabor functions (i.e., scale and orientation) are learned alongside those in the convolutional kernels. In addition, the GCFs can be regenerated after updating the Gabor filters and convolutional kernels. We evaluate the performance of the proposed AGCNs on image classification using five benchmark image datasets, i.e., MNIST and its rotated version, SVHN, CIFAR-10, CINIC-10, and DogsVSCats. Experimental results show that the AGCNs are robust to spatial transformations and have achieved higher accuracy compared with the DCNNs and other state-of-the-art deep networks. Moreover, the GCFs can be easily embedded into any classical DCNN models (e.g., ResNet) and require fewer parameters than the corresponding DCNNs. [ABSTRACT FROM AUTHOR]