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From the fungus Trichoderma sp. , we isolated seven novel 18-residue peptaibols, neoatroviridins E-K (1−7), and six new 14-residue peptaibols, harzianins NPDG J-O (8−13). Additionally, four previously characterized 18-residue peptaibols neoatroviridins A-D (14−17) were also identified. The structural configurations of the newly identified peptaibols (1−13) were determined by comprehensive nuclear magnetic resonance (NMR) and high-resolution electrospray ionization tandem mass spectrometry (HR-ESI-MS/MS) data. Their absolute configurations were further determined using Marfey's method. Notably, compounds 12 and 13 represent the first 14-residue peptaibols containing an acidic amino acid residue. In antimicrobial assessments, all 18-residue peptaibols (1 − 7 , 14 − 17) exhibited moderate inhibitory activities against Staphylococcus aureus 209P, with minimum inhibitory concentration (MIC) values ranging from 8−32 μg·mL−1. Moreover, compound 9 exhibited moderate inhibitory effect on Candida albicans FIM709, with a MIC value of 16 μg·mL−1. [ABSTRACT FROM AUTHOR]

Reinforcement Learning (RL) is an effective method for adaptive traffic signals control. As one type of RL, the teacher-student framework has been found helpful in improving the model performance for different application fields (such as robot control, game, hybrid intelligence), but it is rarely applied for traffic control due to that the hyper-parameters and the number of state-action pairs experienced are difficult to determine. In this work, the teacher-student framework is used for traffic signal control, where only a single reward function is designed to guide the student agent and by using this method the number of hyper-parameters and the model complexity are reduced. Specifically, the teacher agent uses an importance function to evaluate and guide the student, where the importance function combines with environment reward to form a synthetic reward for the student agent. Experimental results under different traffic environments show that the proposed method achieves the expected performance enhancement and is better than most of the state-of-the-art RL-based traffic signal control methods. [ABSTRACT FROM AUTHOR]

Abstract Actinobacteria from special habitats are of interest due to their producing of bioactive compounds and diverse ecological functions. However, little is known of the diversity and functional traits of actinobacteria inhabiting coastal salt marsh soils. We assessed actinobacterial diversity from eight coastal salt marsh rhizosphere soils from Jiangsu Province, China, using culture-based and 16S rRNA gene high throughput sequencing (HTS) methods, in addition to evaluating their plant growth-promoting (PGP) traits of isolates. Actinobacterial sequences represented 2.8%–43.0% of rhizosphere bacterial communities, as determined by HTS technique. The actinobacteria community comprised 34 families and 79 genera. In addition, 196 actinobacterial isolates were obtained, of which 92 representative isolates were selected for further 16S rRNA gene sequencing and phylogenetic analysis. The 92 strains comprised seven suborders, 12 families, and 20 genera that included several potential novel species. All representative strains were tested for their ability of producing indole acetic acid (IAA), siderophores, 1-aminocyclopropane-1-carboxylate deaminase (ACCD), hydrolytic enzymes, and phosphate solubilization. Based on the presence of multiple PGP traits, two strains, Streptomyces sp. KLBMP S0051 and Micromonospora sp. KLBMP S0019 were selected for inoculation of wheat seeds grown under salt stress. Both strains promoted seed germination, and KLBMP S0019 significantly enhanced seedling growth under NaCl stress. Our study demonstrates that coastal salt marsh rhizosphere soils harbor a diverse reservoir of actinobacteria that are potential resources for the discovery of novel species and functions. Moreover, several of the isolates identified here are good candidates as PGP bacteria that may contribute to plant adaptions to saline soils. [ABSTRACT FROM AUTHOR]

Silk proteins are synthesized and secreted by the silk gland. The differential gene expression in it leads to different silk yield among various silkworm strains. As crucial factors, microRNAs (miRNAs) regulate protein synthesis at post-transcriptional level in silk gland. MiRNAs expression level in the silk gland of three silkworm strains (Jingsong, Lan10 and Dazao) was analyzed and 33 differentially expressed miRNAs (DEMs) were discovered between JingSong (JS) and Lan10 (L10), 60 DEMs between JS and Dazao, 54 DEMs between L10 and Dazao respectively. The DEMs target genes were predicted combing with two different methods and their functions were annotated according to gene ontology. Our previous studies showed that a batch of genes related to silk yield were identified in JS and L10 strains by comparative transcriptome and quantitative trait loci (QTL) method. Thirteen DEMs whose target genes are related to protein biosynthesis processes were screened by combining with these researches. Twelve DEMs potentially regulate nineteen genes which exist in our QTL results. Six common DEMs potentially regulate the genes in both of previous results. Finally, five DEMs were selected to verify their expression levels between JS and L10 by qRT-PCR, which showed similar difference as the results of small RNA-sequencing. MiRNAs in the silk gland may directly affect silk protein biosynthesis in different silkworm strains. In current work, we identified a batch of DEMs which potentially regulate the genes related to silk yield. Further functionally study of these miRNAs will contribute to improve varieties and boost the silk yield. Our research provides a basis for studying these miRNAs and their functions in silk production. [ABSTRACT FROM AUTHOR]

The role of austenitic symmetric tilt grain boundaries (STGBs) on the martensitic transformation in NiTi alloy during thermal cycling between 500 K and 10 K are studied from molecular dynamics simulations. Four austenitic STGBs including Σ 3 [ 1 1 ¯ 0 ] ( 111 ) , Σ 3 [ 1 1 ¯ 0 ] ( 112 ) , Σ 9 [ 1 1 ¯ 0 ] ( 114 ) and Σ 9 [ 1 1 ¯ 0 ] ( 221 ) have been considered. Through martensitic transformation, the austenitic STGBs transform to martensitic grain boundaries (GBs) and martensitic twin boundaries form in the interior of the simulation models. After austenitic transformation, the martensitic GBs recover to the austenitic STGBs and the twin boundaries disappear. We find that the roles of STGBs on the martensitic transformation can be divided into three groups based on the martensite start temperature (M s ). (1) The Σ 3 [ 1 1 ¯ 0 ] ( 112 ) and Σ 9 [ 1 1 ¯ 0 ] ( 221 ) STGBs retard the martensitic transformation, i.e., decreases M s , by raising the potential energy of the grain interior. (2) The Σ 9 [ 1 1 ¯ 0 ] ( 114 ) STGB promotes the martensitic transformation by lowering the potential energy of the grain interior. (3) The effects of the Σ 3 [ 1 1 ¯ 0 ] ( 111 ) STGB depend on whether twins form during cooling. The evolutions of the microstructures during thermal loadings are analyzed using the von Mise shear strain; insight obtained in this work paves the way for engineering NiTi shape memory alloy through grain boundaries. [ABSTRACT FROM AUTHOR]

Properties and reliability of using newly-developed pyrolysis and incineration process to dispose typical Waste Electrical and Electronic Equipment (WEEE) like motherboard of personal computer (MPC) and circuit board of Light Emitting Diode subtitle (CBLEDS) (model: FR-4) have been explored by utilizing large-scale self-developed 50.0 kg/h consecutive pyrolysis incinerator. First confined Pyrolysis Chamber (PC) is used to thermally degrade and gasify wastes into gaseous products and chars in low-oxygen level atmosphere first, and gaseous products are transmitted to second confined High-temperature Burning Chamber (HTBC) for further clean incineration in this setup. Diesel oil and pine wood were adopted as piloted ignitor and fuel in PC respectively. Disposed solid WEEE waste materials were mixed at the same mass ratio (wood: circuit board=3:1). The technical reliability (reflected by waste temperature of incinerator, combustion efficiency, gas residence time, thermal reduction rate, mass loss ratio and volume reduction ratio) was analyzed and evaluated, environmental pollution levels of 13 items like SO 2 and NOx were inspected according to a series of Chinese Standards like GB/T16157-1996 and GB18484-2001. Results show flue gas peak temperature of MPC and CBLEDS in HTBC reach 910.0 ℃ and 1120.0 ℃, combustion efficiency in HTBC is as high as 99.90 %, gas residence time of pyrolysis in PC of both MPC and CBLEDS are 3.0 s, their thermally reduction rates of residues are 1.87 % and 1.76 %, mass loss ratios reach 85.80 % and 83.01 % and volume reduction ratios reach 78.06 % and 72.13 % respectively, the detection results of exhaust ringelman emittance hazardous gas and heavy metal content basically comply with atmospheric pollutant emission permit requirements, indicating FR-4 based WEEE can be disposed by consecutive pyrolysis and incineration process quite well with high temperature stability, technical reliability, combustion efficiency and friendly environmental safety. [ABSTRACT FROM AUTHOR]

In this work, the phase transformations induced by thermal cycling between 500 K and 4 K in NiTi are investigated based on molecular dynamics simulations. Completely reversible phase transformations are observed. The B2 phase is found to be always a single crystal at high temperature while single crystal and twinned martensitic phases are observed at low temperature. The martensitic phase transformation completes at about 300 K while various types of martensitic phases are found during the cooling process. In the reverse martensitic transformation, twins are found to be able to decrease the austenite start temperature. Furthermore, three types of detwinning manners related to the thermal hysteresis of NiTi have been discussed. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to study the influence of Ni concentration on the phase transformations in Ni 50 + x Ti 50 − x (0 ≤ x ≤ 2) alloys during thermal cycling between 100 K and 500 K. We successfully reproduce the experimental observations that the martensitic transformation temperature and the thermal hysteresis decrease with increasing Ni concentration when x ≤ 1.5, and the thermally induced martensitic transformation is prohibited when x > 1.5. Three types of martensitic twins are observed; increasing disorder from local distortion in martensitic variants is revealed with increasing Ni concentration at 100 K. Furthermore, a strain glass state with disordered local lattice distortion exists when x > 1.5. In addition, it is found that the atomic distributions of the Ni-Ni and Ti-Ni pairs in strain glass can be significantly altered by temperature. Shape memory effect and pseudoelasticity in strain glass are also analyzed. It is found that the shape memory effect can be characterized by the transformation from frozen strain glass to the martensitic B 1 9 1 ′ twin and the following detwinning, while the pseudoelasticity can be characterized by the transformation from unfrozen strain glass to the B 1 9 1 ′ phase. [ABSTRACT FROM AUTHOR]

Based on annual-cycle survey data collected in 2006–2007 in the southern Yellow Sea (SYS) and analyses on the seasonally chemical hydrologic characteristics of the boundary front of the Yellow Sea Cold Water Mass (YSCWM) and Yellow Sea Warm Current (YSWC), the seasonal variations in upwelling along the frontal zone were determined, and the ecological impacts of the front were investigated. During the generation and dissipation of the YSCWM, the implied upwelling along its western front exhibited seasonal variation. The upwelling first shifted westward from the deep-water region to its westernmost point in summer then returned eastward. The intensity of the upwelling gradually increased from spring to summer and decreased in autumn. In spring, the existence of cold water west of the YSWC was not conducive to the reproduction of phytoplankton. Additionally, the front to the east of this cold water mass also made the western boundary of the phytoplankton bloom region in the central SYS more obvious, forming a prominent chlorophyll a (Chl-a) front. During the entire stratified season (summer and autumn), the upwelling in the frontal zone of the YSCWM played an essential role in maintaining the relatively high concentrations of Chl-a. In winter, the front that formed at the intersection of the YSWC and coastal cold water was also favorable for the formation of the high-Chl-a region. The distribution of anchovy biomass was closely related to the seasonal variations in the position of the frontal zone. In winter and spring, the tongue-shaped warm water and front associated with the intrusion of the YSWC into the SYS had a significant impact on anchovy. During the stratified season in summer and autumn, the development of a front near the boundary of the YSCWM was an important physical driving mechanism for the dense distribution of anchovy. This work enhanced the study of the seasonal relationships between the physical, chemical and biological processes in the frontal zone of the central SYS and deepened our understanding of the ecological significance of this front. [ABSTRACT FROM AUTHOR]

This study aimed to assess the preliminary clinical efficacy and feasibility of the hybrid technique for multilevel cervical myelopathy. Considering the many shortcomings of traditional treatment methods for multilevel cervical degenerative myelopathy, hybrid surgery (bi-level Bryan artificial disc [Medtronic Sofamor Danek, Memphis, TN, USA] replacement and anterior cervical discectomy and fusion) should be considered. Between March 2006 and November 2012, 108 patients (68 men and 40 women, average age 45 years) underwent hybrid surgery. Based on the Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), and Odom’s criteria, the clinical symptoms and neurological function before and after surgery were evaluated. Mean surgery duration was 90 minutes, with average blood loss of 30 mL. Mean follow-up duration was 36 months. At the final follow-up, the mean JOA (± standard deviation) scores were significantly higher compared with preoperative values (15.08 ± 1.47 versus 9.18 ± 1.22; P < 0.01); meanwhile, NDI values were markedly decreased (12.32 ± 1.03 versus 42.68 ± 1.83; P < 0.01). Using Odom’s criteria, the clinical outcomes were rated as excellent (76 patients), good (22 patients), fair (six patients), and poor (four patients). These findings indicate that the hybrid method provides an effective treatment for cervical myelopathy over three consecutive segments, ensuring a good clinical outcome. [ABSTRACT FROM AUTHOR]

This study investigated the coupling of the spatial–temporal variations in nutrient distributions and physical conditions in the southern Yellow Sea (SYS) using data compiled from annual-cycle surveys conducted in 2006–2007 as well as satellite-derived sea-surface temperature (SST) images. The influence of physical dynamics on the distribution and transport of nutrients varied spatially and seasonally in the SYS. The Changjiang Diluted Water (CDW) plume (in summertime), the Subei Coastal Water (SCW) (year-round), and the Lubei Coastal Current (LCC) (in wintertime) served as important sources of nutrients in the inshore area in a dynamic environment. The saline Taiwan Warm Current (TWC) might transport nutrients to the northeast region of the Changjiang Estuary in the summer, and this nutrient source began to increase from spring to summer and decrease when autumn arrived. Three types of nutrient fronts, i.e., estuarine, offshore, and coastal, were identified. A circular nutrient front caused by cross-shelf transport of SCW in the southeast shelf bank area in the winter and spring was observed. The southeastward flow of western coastal cold water in the SYS might be an important conduit for cross-shelf nutrient exchange between the SYS and the East China Sea (ECS). The tongue-shaped low-nutrient region in the western study area in the wintertime was driven by the interaction of the southward Yellow Sea Western Coastal Current (YSWCC) and the biological activity. The vertically variable SCM (subsurface Chl-a maximum) in the central SYS was controlled by coupled physical–chemical processes that involved stratification and associated nutricline. The average nutrient fluxes into the euphotic zone due to upwelling near the frontal zone of the Yellow Sea Cold Water Mass (YSCWM) in the summer are estimated here for the first time: 1.4 ± 0.9 × 10 3 μmol/m 2 /d, 0.1 ± 0.1 × 10 3 μmol/m 2 /d, and 2.0 ± 1.3 × 10 3 μmol/m 2 /d for DIN, PO 4 –P, and SiO 3 –Si, respectively. The depletion of nutrients in the central SYS and the upwelled transport in the boundary of the YSCWM resulted in a spatial transfer of the high Chl-a zone, varying generally from the central SYS to the boundary of the YSCWM from spring to summer, and the nutrient flux associated with this upwelling could contribute significantly to local primary production. This study deepens our understanding of the mechanisms influencing the distribution and transport of nutrients in the SYS. [ABSTRACT FROM AUTHOR]

We propose a schematic diagram for the early transcriptional responses between the susceptible and resistant silkworm strains after AcMNPV infection. In brief, when AcMNPV infect susceptible strains of silkworm, the inhibition of innate immunity and host translational machinery, as well as up-regulation of cytoskeleton, that these responses promote baculoviral BV transport and ingress into the nucleus, thus facilitating the replication of baculovirus. However, when AcMNPV infect resistant strains of silkworm, down-regulation of endocytosis and RNA transport weakened the ability of the baculoviral BV entry into the nucleus, while up-regulation of ribosomal proteins and energy metabolic to inhibit the replication of the virus. [Display omitted] • Early transcriptional responses were analyzed in different resistant strains of silkworm to AcMNPV infection. • Distinct innate immunity and ribosomal response were found between the resistant and susceptible silkworm strains. • Provide basic data for the initial host transcriptional responses to viral infection in silkworm. Baculoviruses are enveloped rod-shaped viruses that with circular double-stranded and large DNA genome. Baculoviruses successfully invade by using the host factors, especially at the process of establishing early infection. In this study, we investigated the different resistant strains of silkworm in response to AcMNPV early infection by RNA-sequencing. Our data revealed that the genes involved in innate immunity and ribosomal proteins were suppressed and cytoskeleton were induced in susceptible strain p50, thus facilitating the viral replication. However, in resistant strain C108, the genes participated in endocytosis and RNA transport were down-regulated, while up-regulation of ribosomal proteins and energy metabolic to inhibit the infection of the virus. These data provide a new sight of the initial host transcriptional responses to viral infection in silkworm. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to study the thermally induced phase transition in NiTi B19′ single crystal at high temperatures (400, 500, 600 and 700 K), B2 single crystal at low temperatures (50, 100, 150 and 200 K) and the system containing a B2/B19′ phase boundary at high, medium (300, 320 and 340 K) and low temperatures. Homogeneous nucleation and growth of the B2 and the B19′ phases are observed in B19′ and B2 single crystal systems, respectively. In B2/B19′ system, heterogeneous nucleation and growth of the B2 phase are observed at high temperatures, which results in forming a B2/B2 grain boundary and a new B2/B19′ phase boundary; the B2 phase transforms homogeneously to B19′ phase at low temperatures; the B2 and B19′ phases coexist without heterogeneous nucleation of any phase at medium temperatures. Compared with the single crystal, the B2/B19′ phase boundary provides the sites for heterogeneous B2 nucleation at high temperatures and has little effect on the phase transition at low temperatures. [ABSTRACT FROM AUTHOR]

One of the proposed mechanisms through which plant growth-promoting endophyte (PGPE) enhances plant growth is the production of 1-aminocyclopropane-1-carboxylic acid deaminase (ACCD). However, information about the endophytic actinobacteria with ACC deaminase activity associated with native plants is still very scarce. In this study, a total of 257 endophytic actinobacterial isolates were obtained using actinobacteria-selective media from surface sterilized roots, stems, leaves and seeds of the oil-seed plant Jatropha curcas L. collected from dry-hot valley soil. Morphological and the 16S rRNA sequence analysis showed that most of the isolates belong to the Streptomyces genus and other non- Streptomyces strains distributed onto 13 genera, with several new species. 19 strains were found to have ACC deaminase activity and they belong to the genera Streptomyces , Nonomuraea , Micrococcus and Kibdelosporangium . The functional ability of the ACC deaminase producing isolates to produce indole-3-acetic acid (IAA), siderophores, mineral phosphate solubilization and growth on nitrogen free semi-solid medium was also determined. Seven strains were selected to inoculate the axenically grown seedlings and they resulted in a significant increase in the seedling fresh weight, the seedling length, the root length and the leaf area of the endophytes-treated seedlings compared to the control. This is the first report on the diversity and characterization of endophytic actinobacteria associated with important oil-seed plant J. curcas L. Our results demonstrate that some endophytic actinobacterial strains have the promising PGP attributes to be developed as biofertilizers to enhance soil fertility and promote the plant growth. [ABSTRACT FROM AUTHOR]