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Background AdpA is a global regulator of morphological differentiation and secondary metabolism in Streptomyces, but the regulatory roles of the Streptomyces AdpA family on the biosynthesis of the natural product ε-poly-l-lysine (ε-PL) remain unidentified, and few studies have focused on increasing the production of ε-PL by manipulating transcription factors in Streptomyces. Results In this study, we revealed the regulatory roles of different AdpA homologs in ε-PL biosynthesis and morphological differentiation and effectively promoted ε-PL production and sporulation in Streptomycesalbulus NK660 by heterologously expressing adpA from S.neyagawaensis NRRLB-3092 (adpASn). First, we identified a novel AdpA homolog named AdpASa in S.albulus NK660 and characterized its function as an activator of ε-PL biosynthesis and morphological differentiation. Subsequently, four heterologous AdpA homologs were selected to investigate their phylogenetic relationships and regulatory roles in S.albulus, and AdpASn was demonstrated to have the strongest ability to promote both ε-PL production and sporulation among these five AdpA proteins. The ε-PL yield of S.albulus heterologously expressing adpASn was approximately 3.6-fold higher than that of the control strain. Finally, we clarified the mechanism of AdpASn in enhancing ε-PL biosynthesis and its effect on ε-PL polymerization degree using real-time quantitative PCR, microscale thermophoresis and MALDI-TOF–MS. AdpASn was purified, and its seven direct targets, zwf, tal, pyk2, pta, ack, pepc and a transketolase gene (DC74_2409), were identified, suggesting that AdpASn may cause the redistribution of metabolic flux in central metabolism pathways, which subsequently provides more carbon skeletons and ATP for ε-PL biosynthesis in S.albulus. Conclusions Here, we characterized the positive regulatory roles of Streptomyces AdpA homologs in ε-PL biosynthesis and their effects on morphological differentiation and reported for the first time that AdpASn promotes ε-PL biosynthesis by affecting the transcription of its target genes in central metabolism pathways. These findings supply valuable insights into the regulatory roles of the Streptomyces AdpA family on ε-PL biosynthesis and morphological differentiation and suggest that AdpASn may be an effective global regulator for enhanced production of ε-PL and other valuable secondary metabolites in Streptomyces.

PbSe has attracted considerable attention due to its promising applications in optoelectronics and energy harvesting. In this work, we explore the lateral photovoltaic effect (LPE) of PbSe films with a simple PbSe/Si heterostructure under nonuniform light illumination and zero-bias conditions. The LPE response is strongly dependent on the thickness of the PbSe film, but always shows a linear dependence on the laser spot position in an ultra-large working size of 5 mm and exhibits a wide photoresponse ranging from visible to near-infrared. The maximum position sensitivity can reach up to 190 mV/mm for the 15-nm-thick PbSe device at 1064 nm and nonlinearity is less than 4%, demonstrating its new potential application in novel position sensitive detectors (PSDs). Besides, the device also shows an ultrafast response speed, with the rise and fall time of ∼40 µs and ∼105 µs, respectively, and excellent reproducibility. These results bring great inspirations for developing high-performance broadband and self-powered PSDs based on the PbSe/Si heterostructure.

Anisotropic antimony selenide (Sb

Hydrogels have been extensively favored as drug and cell carriers for the repair of knee cartilage defects. Recruiting mesenchymal stem cells (MSCs) in situ to the defect region could reduce the risk of contamination during cell delivery, which is a highly promising strategy to enhance cartilage repair. Here, a cell-free cartilage tissue engineering (TE) system was developed by applying an injectable chitosan/silk fibroin hydrogel. The hydrogel system could release first stromal cell-derived factor-1 (SDF-1) and then kartogenin (KGN) in a unique sequential drug release mode, which could spatiotemporally promote the recruitment and chondrogenic differentiation of MSCs. This system showed good performance when formulated with SDF-1 (200 ng/mL) and PLGA microspheres loaded with KGN (10 μΜ). The results showed that the hydrogel had good injectability and a reticular porous structure. The microspheres were distributed uniformly in the hydrogel and permitted the sequential release of SDF-1 and KGN. The results of in vitro experiments showed that the hydrogel system had good cytocompatibility and promoted the migration and differentiation of MSCs into chondrocytes. In vivo experiments on articular cartilage defects in rabbits showed that the cell-free hydrogel system was beneficial for cartilage regeneration. Therefore, the composite hydrogel system shows potential for application in cell-free cartilage TE. Schematic illustration of functional injectable hydrogel system for cartilage regeneration. (1) Preparation of hydrogel with the function for spatiotemporal releasing SDF-1 and KGN; (2) Spatiotemporal regulation of MSCs recruitment and chondrogenic differentiation by hydrogel in vitro; (3) Implantation of hydrogel and cartilage regeneration.

BackgroudEarly diagnosis of hepatocellular carcinoma (HCC) has not been clinically resolved, which has been causing more death in patients with HCC. HCC is also a systemic disease related to disorders of blood homeostasis, and the association of red blood cells (RBCs) and HCC tumorigenesis is still elusive. This study explored the protein characteristics of RBCs at the progressive pathological stages comparing with healthy individuals, including liver cirrhosis (LC) and established HCC, to fully understand the tumorigenesis of HCC from a different view and identify potentially novel diagnostic biomarkers for HCC in RBCs.MethodsData independent acquisition (DIA) proteomic analyses were performed with 72 clinical RBCs samples from a cohort of subjects including HCC, LC and healthy controls. Bioinformatics analysis was conducted for significantly differentially expressed proteins (DEPs) through the whole process of tumorigenesis to characterize the clinical relevanve of RBCs and tumorigenesis in HCC. The highly potential tumorigenesis-associated molecular biomarkers were evaluated with clinical samples by parallel reaction monitoring (PRM) technology.ResultsWe observed that red blood cells number dynamically changes during the tumorigenesis of HCC, and LC is a developmental stage more closely approaching HCC based on the protein expresson profiles in RBCs. The expression of hemoglobin (HbA, HbF) in erythroid cells also dynamically alters during the whole process of HCC tumorigenesis, suggesting immature erythroid cells exist in peripheral blood of HCC patients and erythropoiesis in the patients starts to be influenced with the occurance of LC. We observed that the autophagy pathway is disturbed in RBCs with the onset of LC and maintained during the tumorigenesis of HCC. Oxytocin pathway and GnRH pathway are disturbed and first identified during the development of LC into HCC. SMIM1, ANXA7, HBA1 and HBE1 that are significantly altered during tumorigenesis were verified as promising biomarkers for HCC early diagnosis.ConclusionsThis study underlied the clinical relevance of the proteins in RBCs and the tumorigenesis of HCC, and provided the potential biomarkers for early diagnosis in HCC from a new perspective. Our results provided a novel strategy with RBCs for HCC early diagnosis, which will improve the translational research and application in diagnosis of HCC.

When a sarcomatous neoplasm is identified in the breast, distinguishing metaplastic carcinoma, malignant phyllodes tumor (MPT), and primary sarcoma is a diagnostic challenge, especially on small biopsies, as all these tumors may have overlapping morphological features, thoroughly grossing with histological examination and immunohistochemical staining being the standard approach to aid in classifying these lesions. Recently, we identified a highly sensitive and specific breast carcinoma marker TRPS1 with high expression in metaplastic breast carcinoma. In the current study, we tested TRPS1 in MPTs and primary sarcoma of the breast. We found TRPS1 was highly expressed (95%) within spindle cell, chondro-osseous, and/or liposarcomatous components of MPTs, in all breast primary chondrosarcomas and extraskeletal osteosarcomas, but not in other sarcomas of the breast. In extramammary sarcomas, TRPS1 was expressed in 28% of conventional chondrosarcomas and 56% of osteosarcomas of bone, but rarely in undifferentiated pleomorphic sarcomas (UPSs), liposarcomas, and angiosarcomas. In summary, MPTs may share similar genetic background with metaplastic carcinoma exhibiting TRPS1 expression, and TRPS1 may play a role in chondro-osseous differentiation because of its expression in chondro-osseous sarcomas from both breast and extramammary sites. Our findings suggest TRPS1 may be clinically useful in distinguishing MPT and metaplastic carcinoma from primary breast sarcoma except for tumors with chondro-osseous differentiation.

Reduced dimension is one of the effective strategies to modulate thermoelectric properties. In this work, n-type PbSe/SnSe superlattices with quantum-well (QW) structure are fabricated by pulsed laser deposition. Here, it is demonstrated that the PbSe/SnSe multiple QW (MQW) shows a high power factor of ≈25.7 µW cm-1 K-2 at 300 K, four times larger than that of PbSe single layers. In addition, thermal conductivity falls below 0.32 ± 0.06 W m-1 K-1 due to the phonon scattering at interface when the PbSe well thickness is confined within the scale of phonon mean free path (1.8 nm). Featured with ultrahigh power factor and ultralow thermal conductivity, ZT at room temperature is significantly increased from 0.14 for PbSe single layer to 1.6 for PbSe/SnSe MQW.

With the development of cloud computing, service computing, IoT(Internet of Things) and mobile Internet, the diversity and sociality of services are increasingly apparent. With the increasing complexity of collaborative relationships between services, service ecosystems are beginning to emerge with the characteristics of natural ecosystems, economic systems and complex networks. Under this context, how to realize systematic evaluation of service ecosystem is of great significance to promote its sound development. Based on this, this paper proposes a value entropy model that links the operating state of the system with the efficiency of value creation, which helps to clarify the performance of the service ecosystem from the perspective of multi-dimensional integration. In addition, a computational experiment system is established to verify the effectiveness of value entropy model, which stimulates the competitive evolution process of two service ecosystems with different strategies. The result shows that our model can provide new ideas for the analysis of service ecosystem evolution, and can also provide decision support for the optimization of operation strategy.

Smart services are playing an increasingly important role in the operation of our society. Exploring the evolution mechanism, boundaries and challenges of service ecosystem is essential to our ability to realize smart digital society, reap its benefits and prevent potential risks. We argue that this necessitates a broad scientific research agenda to study service ecosystem that incorporates and expands upon the research area of service computing and includes insights from across the disciplines. We firstly outline a set of research issues that are fundamental to this emerging field, and then explores the technical, social, legal and institutional challenges on the study of service ecosystem.

This paper proposes a framework to guide us in designing and implementing our classroom language pedagogy. It is based on three major principles which the teacher can keep constantly in mind: that the learners need to be engaged, that the language needs to be memorized, and that learning needs to move toward communicative competence. Each principle generates between two and four dimensions which the teacher can use to develop specific strategies.

Polyhydroxyalkanoate (PHA), a class of biopolyester synthesized by various bacteria, is considered as an alternative to petroleum-based plastics because of its excellent physochemical and material properties. Pseudomonas putida KT2440 can produce medium-chain-length PHA (mcl-PHA) from glucose, fatty acid and glycerol, and its whole-genome sequences and cellular metabolic networks have been intensively researched. In this study, we aim to improve the PHA yield of P. putida KT2440 using a novel promoter engineering-based strategy. Unlike previous studies, endogenous strong promoters screening from P. putida KT2440 instead of synthetic or exogenous promoters was applied to the optimization of PHA biosynthesis pathway. Based on RNA-seq and promoter prediction, 30 putative strong promoters from P. putida KT2440 were identified. Subsequently, the strengths of these promoters were characterized by reporter gene assays. Furthermore, each of 10 strong promoters screened by transcriptional level and GFP fluorescence was independently inserted into upstream of PHA synthase gene (phaC1) on chromosome. As a result, the transcriptional levels of the phaC1 and phaC2 genes in almost all of the promoter-substituted strains were improved, and the relative PHA yields of the three promoter-substituted strains KTU-P1C1, KTU-P46C1 and KTU-P51C1 were improved obviously, reaching 30.62 wt%, 33.24 wt% and 33.29 wt% [the ratio of PHA weight to cell dry weight (CDW)], respectively. By further deletion of the glucose dehydrogenase gene in KTU-P1C1, KTU-P46C1 and KTU-P51C1, the relative PHA yield of the resulting mutant strain KTU-P46C1-∆gcd increased by 5.29% from 33.24% to 38.53%. Finally, by inserting P46 into upstream of pyruvate dehydrogenase gene in the genome of KTU-P46C1-∆gcd, the relative PHA yield and CDW of the resulting strain KTU-P46C1A-∆gcd reached nearly 42 wt% and 4.06 g/l, respectively, which increased by 90% and 40%, respectively, compared with the starting strain KTU. In particular, the absolute PHA yield of KTU-P46C1A-∆gcd reached 1.7 g/l, with a 165% improvement compared with the strain KTU. Herein, we report the highest PHA yield obtained by P. putida KT2440 in shake-flask fermentation to date. We demonstrate for the first time the effectiveness of endogenous strong promoters for improving the PHA yield and biomass of P. putida KT2440. More importantly, our findings highlight great potential of this strategy for enhanced production of secondary metabolites and heterologous proteins in P. putida KT2440.

Salmonella should be absence in pharmaceutical preparations and foods according to regulations in many countries. Up to now, rapidly detecting Salmonella at 1 CFU·[10 g (mL) ]-1 in pharmaceutical preparation or 1 CFU·[25 g (mL)] -1 in food samples is still a challenge. Herein, we present an aptamer-based surface-enhanced Raman spectroscopy (SERS) method for rapidly detecting Salmonella Enteritidis by using a handheld Raman instrument. The aptamer could specifically recognize S. Enteritidis, and 4-MBA self-assembled on the surface of Au@Ag NPs was used as a Raman reporter molecule. The method was validated to be high specific with no interference from other five pathogenic bacteria. It could identify S. Enteritidis contaminant at ∼1 CFU·(10 g)-1 spiked level in a real sample (Wenxin granule, a botanical drug) after 6 h of enrichment. The detection time was much shorter than that of the methods (more than 54∼96 h) in the standards of pharmaceutical preparations and foods. In addition, the method could quantitatively determinate S. Enteritidis with satisfactory results. The SERS peak intensities of 4-MBA at 1072 cm-1 showed a good linear correlation (R2 =0.9873) with the logarithms of S. Enteritidis concentrations ranging from 4.17×102 to 1.39×107 CFU·mL-1. T-test result (P=0.425) revealed that there was no significant difference between the determination results obtained by the SERS method and the plate counting method. Therefore, the study indicated that the method was practical and reliable, and it could be a promising alternative for on-site detection of S. Enteritidis.

Antimony selenide (Sb2Se3) nanorod arrays along the [001] orientation are known to transfer photogenerated carriers rapidly due to the strongly anisotropic one‐dimensional crystal structure. With advanced light‐trapping structures, the Sb2Se3 nanorod array‐based solar cells have excellent broad spectral response properties, and higher short‐circuit current density than the conventional planar structured thin film solar cells. However, the interface engineering for the Sb2Se3 nanorod array‐based solar cell is more crucial to increase the performance, because it is challenging to coat a compact buffer layer with perfect coverage to form a uniform heterojunction interface due to its large surface area and length–diameter ratio. In this work, an intermeshing In2S3 nanosheet‐CdS composite as the buffer layer, compactly coating on the Sb2Se3 nanorod surface is constructed. The application of In2S3‐CdS composite buffers build a gradient conduction band energy configuration in the Sb2Se3/buffer heterojunction interface, which reduces the interface recombination and enhances the transfer and collection of photogenerated electrons. The energy‐level regulation minimizes the open‐circuit voltage deficit at the interfaces of buffer/Sb2Se3 and buffer/ZnO layers in the Sb2Se3 solar cells. Consequently, the Sb2Se3 nanorod array solar cell based on In2S3‐CdS composite buffers achieves an efficiency of as high as 9.19% with a V OC of 461 mV., An intermeshing In2S3 nanosheet‐CdS composite buffer layer is constructed and applied in Sb2Se3 nanorod array solar cells, which build a gradient conduction band energy configuration in the Sb2Se3/buffer heterojunction interface. The champion cell based on In2S3‐CdS composite buffers achieves a PCE of 9.19% with an V OC of as high as 461 mV.

Landslide is one of the most common geological disasters, among which creeping landslide is the most widespread. The process of landslide is very slow, so it is necessary to continuously monitor and analyze the elasticity of creep landslide for disaster risk prediction. Based on the fuzzy measure theory, the membership function and distribution density function of the fuzzy measure model are determined, and the seismic stability of a large rock in China is calculated and analyzed. In the process of analysis, it is necessary to determine the main parameters affecting the stability of rock, that is, to use the artificial neural network analysis method to determine the parameters related to rock characteristics and explosion dynamics. The probability of rock failure can be obtained by using fuzzy measurement model. This paper studies the efficacy of fluoxetine combined with psychological intervention in adolescent depression and its impact on memory. The Chinese Biomedical Literature Database, Chinese Journal Full-Text Database, and VIP Chinese Science and Technology Journal Database were searched from the establishment of each database to October 2020. At the same time, the journals in related fields were manually searched, the randomized controlled trials meeting the inclusion criteria were extensively searched, and the Revman 5.0 software was used for statistical analysis. In this paper, through research, we developed a combination of fluoxetine and psychological intervention to treat adolescent depression with definite cure characteristics, which may be related to the regulation and reduction of the balance of 5-HT and NE levels in the blood, which can significantly improve the learning and memory ability of patients and reduce the recurrence rate.

In recent years, narrowband photodetectors (PDs) have been widely used in color imaging, spectral detection or discrimination, defense, and scientific research due to their special spectral selective responses. In this work, by combining organic-inorganic hybrid perovskite layers of different band gaps and thicknesses, a series of narrowband perovskite heterojunction PDs with a continuously adjustable spectral range in the visible and near-infrared range are designed and prepared. The PDs can achieve a narrowband photoresponse with a full width at half-maximum (FWHM) of less than 50 nm and a light rejection ratio (between 780 and 532 nm) of over 1100 and exhibit excellent photoresponse performances with an external quantum efficiency (EQE), responsivity (R), and detectivity (D*) as high as 50.3%, 0.331 A/W, and 4.27 × 1010 Jones, respectively. More importantly, the photoresponses of the PDs at zero bias are as good as those at the reverse bias voltages, indicating the outstanding self-powered property. In addition, a fast response time of ∼180/∼200 μs is obtained in the narrowband perovskite heterojunction, and the response speed nearly remains constant for different PDs in the whole tunable wavelength range, demonstrating the suitable and stable structure of the heterojunction, as well as the high crystalline quality of the perovskite layers. This work definitely provides a simple strategy for designing low-cost, high-photoresponsivity, fast speed, and self-powered narrowband PDs with a tunable spectral range.

The increasing global demand for rare earth elements (REEs) has led to their recognition as emerging contaminants; however, the effect that biota have on the cycling of these elements at the watershed scale is not currently well understood. In this study, water samples and field freshwater clams Corbicula fluminea were concurrently collected along watershed gradients, and concentration profiles of 14 naturally occurring REEs were measured in operationally defined water fractions and soft tissues of the freshwater clams. Moreover, Post Archean Australian Shale (PAAS) normalized REE patterns, fractionation indices, and anomalous values were determined to further extract characteristic features. As a result, both the water and biological samples had variable REE compositions, with higher concentrations of light REEs (LREEs) than middle REEs (MREEs) and heavy REEs (HREEs), while decreasing concentrations were generally observed as filter pore size decreased, implying that large colloidal and particulate fractions were important carriers of REEs. The spatial distribution patterns of REEs revealed a clear site effect among profiles, with variability more pronounced among watersheds and with peaks in sites from a small watershed near the hotspots of the mining area, and then exhibited a decreasing trend with distance from there. Meanwhile, significant bioaccumulation of REEs was observed potentially reflecting different degrees of contamination gradients among the watersheds. The PAAS-normalized distribution patterns tended to be slightly enriched in MREEs, producing a peculiar “roof-shaped” feature and characteristic fractionation. Remarkably, bio-concentration factors (BCFs) highlighted the importance of large colloidal and particulate phases in assessing biologically available REEs for filter-feeding species. Collectively, our study strongly favored that accumulation patterns and fractionation characteristics of REEs in C. fluminea can serve as a reliable indicator of geochemical behavior, providing a promising biomonitoring tool to quantitatively denote different degrees of REE contamination and assess possible impacts in mining watersheds.

Motivation plays an important role in learning foreign languages and many scholars have conducted research on how to maintain and enhance students’ motivation in the EFL class. But few studies have analyzed whether there are mismatches between what teachers and learners define as the important factors to motivate students. This study aims to rectify this gap in our knowledge by analyzing university students’ and teachers’ perceptions of students’ English learning motivation based on self-determination theory (SDT) and the ‘5Ts’ which affect motivation (Teacher, Teaching Methodology, Text, Task and Test). In order to have a better understanding of students’ and teachers’ perceptions, two questionnaires were designed. Participants were 190 Chinese university students and 122 English teachers. Results show that teachers and learners have different perspectives for Task and Teacher. To be specific, teachers gave more weight to the Task factor, whereas students focus more on the Teacher factor, including good characteristics of their teacher. However, teachers and students agree that Teaching methodology and Text play a vital role in motivating students. They also agree that Test is less important. These findings have pedagogical implications for current and prospective English teachers in China and elsewhere.

Aim: Host remolding with scaffolds degradation and rapid formation of a complete endothelium, are prospective solutions for improving performance of small diameter vascular grafts. Materials & methods: For this purpose, microfibrous polycaprolactone (PCL)/gelatin scaffolds were prepared by electrospinning and subsequently functionalized with heparin and organoselenium-immobilized polyethyleneimine for nitric oxide generation through layer-by-layer self-assembly. Results: Our results showed that modified PCL/gelatin grafts had strong catalytic nitric oxide generation capacity and facilitated the enhanced attachment of endothelial cells, compared with control scaffold groups. Meanwhile, the modified grafts exhibited good hemocombatility, rapid endothelialization and smooth muscle cell regeneration. Conclusion: Modification of biodegradable scaffolds, proposed in this work, could enhance biological functions of vascular grafts and provides new strategies for the construction of small diameter vascular grafts.

There has been substantial progress made in the development of bone regeneration materials, driven by the deficiencies that exist in current clinical products, such as finite sources, donor site complications, and potential for disease transmission. To overcome these shortcomings, multifunctional scaffolds should be developed to integrate the relationship among osteoinduction, osteoconduction, and osseointegration. In this study, we fabricated polycaprolactone/gelatin (PG) nanofiber films by electrospinning, to act as barriers against connective tissue migration into bone defect sites; chitosan/poly (γ-glutamic acid)/hydroxyapatite (CPH) hydrogels were formed by electrostatic interaction and lyophilization, to exert osteoconduction; and platelet-rich fibrin (PRF) was extracted from rat abdominal aorta and combined with composite scaffolds, to promote bone induction through the release of growth factors. Hydrogels were immersed in simulated body fluid (SBF) for 1 month to investigate mineralization in vitro. Cytocompatibility, cell barrier effect, and osteogenic differentiation were also explored in vitro. The ability to effectively regenerate bone was analyzed by implantation of triple-layered composite scaffolds into rat calvarial defects in vivo. Size-matched hydrogel filled the defect site, and then, fresh PRF was applied to the hydrogel surface. Finally, P2G3 nanofiber films were applied and attached to the surrounding soft tissue. In short, we fabricated multifunctional triple-layered scaffolds by combining the advantages of osteoinduction, osteoconduction, and osseointegration, which could give full play to the role of PRF in bone regeneration and provide new and pragmatic concepts for bone tissue regeneration in clinical applications.

O2O (online to offline) service recommendation is a typical context-aware service application, which needs to provide the most suitable services to customers in time according to their user profile and current context. By means of composing various data sources, different O2O service recommendation strategies can be customized, which may lead to great performance difference. Incorrect or non-real-time service recommendation would not work well and even cause negatives consequences. As a result, how to evaluate the performance of different O2O service recommendation strategies and select the most suitable one has become a key problem in the field. Due to the diversity and the variability of context events, as well as the economic, legal, and ethical impact, it is difficult or even impossible for traditional methods to realize comprehensive evaluation of various service strategies. Based on the background, this paper proposes a computational experiment-based evaluation method of O2O service recommendation strategies, which mainly consists of three parts: customization of O2O service strategies, modeling of experiment system, and execution of experiment evaluation. As a case study, the method was applied to Food O2O service. Three kinds of service strategies were compared respectively under two different market environments. Experiment results show that the proposed evaluation method is effective.

The unabated inflammatory response is often the cause for inhibited vascular regeneration of transplanted small-diameter vascular grafts (diameter6 mm) in vascular replacement therapies. We proposed that stimulating inflammatory resolution could be an effective approach for treatment of chronic vascular graft inflammation after transplantation. Aspirin-Triggered Resolvin D1 (AT-RvD1) plays critical roles in driving cellular processes toward the resolution of inflammation and suppressing downstream inflammatory signaling pathways. With the aim to facilitate vascular regeneration, we developed a polycaprolactone (PCL) vascular graft loaded with AT-RvD1. The results showed that AT-RvD1 promoted macrophage polarization into M2 macrophages in vitro. Macrophages pretreated with AT-RvD1 conditioned medium promoted endothelial cell tube formation. Furthermore, in vivo implantation was performed by replacing rat abdominal aorta. We observed fast endothelialization and enhanced smooth muscle regeneration in rats that received the AT-RvD1-containing graft implants. The presence of AT-RvD1 induced infiltration of a large number of M2 macrophages and integrin α4-positive (CD49d

For the photovoltaic effect (PE), the surface potential is suggested to be an adverse factor, and researchers usually try to increase the thickness of the conductive layer or the number of strip electrodes to avoid it. However, the potential can still not be eliminated. More importantly, the huge cost has to be paid, and the photovoltaic performances are largely reduced. While the drawback of potential in PE may become excellent merit in lateral PE (LPE) due to their different working mechanisms. Moreover, the decreasing thickness of the conductive layer may be inversely used as an efficient method to modulate the LPE performances. In this paper, the indium tin oxide (ITO) conductive layer thickness-dependent LPE responses are well studied in the copper indium gallium selenide (CIGS) heterostructure. The LPE response is significantly improved with ITO thickness decreasing from 150 to 10 nm, and the thickness-dependent enhancement is strongly dependent on the illumination intensity, especially in high illumination intensities, a nonmonotonic thickness dependence is obtained. In addition, it is found that the heterostructure exhibits an ultrafast response speed of ~14.5 $\mu$ s/~15.0 $\mu$ s, and what is more, the response time nearly remains constant without depending on the ITO thickness.

Total metal concentrations and acid-volatile sulfide (AVS) measurements coupled with simultaneously extracted metals (SEM) were determined in heterogeneous sediments from Maluan Bay, China. Zn was the predominant component of SEM, while Cd was the least. In sediment cores, AVS increased with sediment depth, followed by a decrease with large variation, while SEM fluctuated. Multiple empirical sediment quality guidelines (SQGs) and equilibrium partitioning (EqP) approaches were applied to assess the contamination degree, sediment quality and potential risks associated with bioavailable metals, indicating that not all sediments with [SEM]-[AVS] > 0 were capable of causing toxicity because TOC is also an important metal-binding phase. In order to screen out the physicochemical variability and the complexity and large variance of datasets, multivariate statistical techniques were utilized to comprehensively reveal pollution status by visualized factor scores. Collectively, this study favors the integrative utilization of multifarious methods to scientifically diagnose the pollution characterization for sustainable coastal management.

Summary Cotton is widely cultivated globally because it provides natural fibre for the textile industry and human use. To identify quantitative trait loci (QTLs)/genes associated with fibre quality and yield, a recombinant inbred line (RIL) population was developed in upland cotton. A consensus map covering the whole genome was constructed with three types of markers (8295 markers, 5197.17 centimorgans (cM)). Six fibre yield and quality traits were evaluated in 17 environments, and 983 QTLs were identified, 198 of which were stable and mainly distributed on chromosomes 4, 6, 7, 13, 21 and 25. Thirty‐seven QTL clusters were identified, in which 92.8% of paired traits with significant medium or high positive correlations had the same QTL additive effect directions, and all of the paired traits with significant medium or high negative correlations had opposite additive effect directions. In total, 1297 genes were discovered in the QTL clusters, 414 of which were expressed in two RNA‐Seq data sets. Many genes were discovered, 23 of which were promising candidates. Six important QTL clusters that included both fibre quality and yield traits were identified with opposite additive effect directions, and those on chromosome 13 (qClu‐chr13‐2) could increase fibre quality but reduce yield; this result was validated in a natural population using three markers. These data could provide information about the genetic basis of cotton fibre quality and yield and help cotton breeders to improve fibre quality and yield simultaneously.

The pump fluence- and amplitude of magnetic field-dependent demagnetization and dynamic processes are well studied in the Co2FeAl(CFA) films prepared on the MgO substrates at different temperatures by the time resolved magneto-optical Kerr effect (TR-MOKE). It is found that the demagnetization and the damping processes are strongly dependent on both the amplitude of the external fields and the pump fluences in low fields, resulting in a complex spin relaxation and damping behavior, which is mainly attributed to the non-uniform precession mode induced by the inhomogeneous magnetic anisotropy distribution and the anisotropy field competition. However, with increasing magnetic field gradually, the demagnetization and dynamic processes start to be dominated by the external field, and meanwhile the uniform spin-wave arises. More importantly, the dynamic properties are nearly independent of the amplitude of the magnetic fields and the pump fluences again. The constant damping parameter, which decreases slightly from 4.02 × 10−3 to 1.55 × 10−3 with grown temperature changing from 300 °C to 700 °C, is suggested to be an intrinsic characteristic of the CFA films, and can be attributed to the improvement of the atomic ordering and the crystal quality.

IntroductionGefitinib, well known as a new antitumor agent, has been applied in various cancers such as oral squamous cell carcinoma (OSCC). However, most patients eventually acquire resistance to gefitinib, and the molecular mechanism of gefitinib resistance is not well described. Bone marrow stromal cell antigen 2 (BST2) has been reported to promote tumor cell growth and confer chemotherapy resistance in various cancers. However, the roles of BST2 in OSCC still need to be fully understood.Material and methodsWe determined the expression of BST2 in OSCC tissues using qRT-PCR, immunohistochemistry and western blot. Next, we used MTT assay, flow cytometry and western blot to determine the roles of BST2 in OSCC cell proliferation, cycle progression and apoptosis, respectively. Furthermore, we evaluated the effect of BST2 on gefitinib resistance in OSCC cells and explored the related molecular mechanism.ResultsBST2 expression was up-regulated in OSCC tissues compared with the adjacent normal tissues. BST2 overexpression significantly enhanced OSCC cell proliferation, mediated the cell cycle progression and inhibited cell apoptosis. Additionally, the results showed that BST2 overexpression effectively induced gefitinib resistance in OSCC cells. Subsequent analysis revealed that the underlying mechanism was associated with activation of the EGFR pathway.ConclusionsOur study indicated that BST2 promoted growth and induced gefitinib resistance in OSCC cells, at least partially, through regulating the EGFR pathway. Thus, BST2 could be used as a therapeutic target for gefitinib resistance in OSCC.

Summary Poly‐γ‐glutamic acid (γ‐PGA) is a biocompatible and biodegradable polypeptide with wide‐ranging applications in foods, cosmetics, medicine, agriculture and wastewater treatment. Bacillus amyloliquefaciens LL3 can produce γ‐PGA from sucrose that can be obtained easily from sugarcane and sugar beet. In our previous work, it was found that low intracellular glutamate concentration was the limiting factor for γ‐PGA production by LL3. In this study, the γ‐PGA synthesis by strain LL3 was enhanced by chromosomally engineering its glutamate metabolism‐relevant networks. First, the downstream metabolic pathways were partly blocked by deleting fadR, lysC, aspB, pckA, proAB, rocG and gudB. The resulting strain NK‐A6 synthesized 4.84 g l−1 γ‐PGA, with a 31.5% increase compared with strain LL3. Second, a strong promoter PC 2up was inserted into the upstream of icd gene, to generate strain NK‐A7, which further led to a 33.5% improvement in the γ‐PGA titre, achieving 6.46 g l−1. The NADPH level was improved by regulating the expression of pgi and gndA. Third, metabolic evolution was carried out to generate strain NK‐A9E, which showed a comparable γ‐PGA titre with strain NK‐A7. Finally, the srf and itu operons were deleted respectively, from the original strains NK‐A7 and NK‐A9E. The resulting strain NK‐A11 exhibited the highest γ‐PGA titre (7.53 g l−1), with a 2.05‐fold improvement compared with LL3. The results demonstrated that the approaches described here efficiently enhanced γ‐PGA production in B. amyloliquefaciens fermentation.

As a new form of manufacturing industry in the Internet era, social manufacturing has its inherent “social-cyber” complexity: the source of manufacturing service is social, and such sociality aggravates the diversity, uncertainty, and dynamics of service supply. This poses new challenges to the service matching between supply-side and demand-side. In order to meet this challenge, it is necessary to conduct a complexity analysis of social manufacturing. Traditional researches mainly rely on data statistics and macro analysis, in which there are difficulties in clearly identifying the links between various impact factors and macro evolution phenomena. In order to change such a situation, this paper proposes a modeling framework of social manufacturing from the aspect of social learning evolution (SLE), including individual evolution model, organizational learning model, and social learning model. Based on the SLE framework, the corresponding computational experiment system is built to analyze the complexity of social manufacturing. The performance of several evolution mechanisms in social manufacturing is simulated and compared as a case study to present the application of SLE framework. The results demonstrate that our method has a substantial promise.

Interest in lanthanide complexes in the synthetic clays remains growing considerably during the last decades because of the attractive features of the individuals. Synthetic clays like Laponite® and Aminoclay show great potentials in building up the luminescent hybrid materials due to their obvious advantages such as high purity, high dispersibility (or solubility) in water to yield translucent gels and clear aqueous solution. Additionally, their strong adsorption capacity for non-polar molecules or complexes is favorable to the formation of water-soluble and aqueous processable luminescent materials. This feature article summarizes the latest developments in the design and preparation of highly luminescent organic-inorganic hybrid materials with excellent aqueous process ability based on lanthanide complexes intercalated synthetic clays.

Background Iturins, which belong to antibiotic cyclic lipopeptides mainly produced by Bacillus sp., have the potential for application in biomedicine and biocontrol because of their hemolytic and antifungal properties. Bacillus amyloliquefaciens LL3, isolated previously by our lab, possesses a complete iturin A biosynthetic pathway as shown by genomic analysis. Nevertheless, iturin A could not be synthesized by strain LL3, possibly resulting from low transcription level of the itu operon. Results In this work, enhanced transcription of the iturin A biosynthetic genes was implemented by inserting a strong constitutive promoter C2up into upstream of the itu operon, leading to the production of iturin A with a titer of 37.35 mg l−1. Liquid chromatography-mass spectrometry analyses demonstrated that the strain produced four iturin A homologs with molecular ion peaks at m/z 1044, 1058, 1072 and 1086 corresponding to [C14 + 2H]2+, [C15 + 2H]2+, [C16 + 2H]2+ and [C17 + 2H]2+. The iturin A extract exhibited strong inhibitory activity against several common plant pathogens. The yield of iturin A was improved to 99.73 mg l−1 by the optimization of the fermentation conditions using a response surface methodology. Furthermore, the yield of iturin A was increased to 113.1 mg l−1 by overexpression of a pleiotropic regulator DegQ. Conclusions To our knowledge, this is the first report on simultaneous production of four iturin A homologs (C14–C17) by a Bacillus strain. In addition, this study suggests that metabolic engineering in combination with culture conditions optimization may be a feasible method for enhanced production of bacterial secondary metabolites. Electronic supplementary material The online version of this article (10.1186/s12934-019-1121-1) contains supplementary material, which is available to authorized users.

As a new form of manufacturing industry in cloud environment, social manufacturing has its inherent “social–cyber” complexity: the source of enterprise services is social, and this sociality aggravates the diversity, uncertainty and dynamics of service supply. Researchers have done a lot to improve the adaptability of service matching strategies. However, it is difficult or even impossible to for traditional methods to evaluate the viability of these strategies because of the “social–cyber” complexity. This poses new challenges to how to evaluate and optimize these strategies in a complex social manufacturing environment. Aiming at the problem, this paper proposes a computational experiment-based evaluation framework, which can simulate all kinds of actual scenarios to verify the performance of service matching strategies. This method includes three parts: (1) design of supply & demand matching strategy; (2) construction of computational experiment system; (3) performance evaluation of service strategies in different experiment environments. A case study is given to verify the applicability of our method by means of comparing several adaptive service matching strategies (supply-oriented, demand-oriented, initial supply & demand-oriented, optimized supply & demand-oriented) in two kinds of market environments. The results demonstrate that our method has a substantial promise.

Highly oriented Bi2-xSbxTe3 (x = 0, 0.7, 1.1, 1.5, 2) ternary nanocrystalline films were fabricated using vacuum thermal evaporation method. Microstructures and morphologies indicate that Bi2-xSbxTe3 films have pure rhombohedral phase with well-ordered nanopillars array. Bi, Sb and Te atoms uniformly distributed throughtout films with no precipitation. Electrical conductivity of Bi2-xSbxTe3 films transforms from n-type to p-type when x > 1.1. Metal-insulator transition was observed due to the incorporation of Sb in Bi2Te3. Bi2-xSbxTe3 film with x = 1.5 exhibits optimized electrical properties with maximum electrical conductivity σ of 2.95 × 105 S m−1 at T = 300 K, which is approximately ten times higher than that of the undoped Bi2Te3 film, and three times higher than previous report for Bi0.5Sb1.5Te3 films and bulk materials. The maximum power factor PF of Bi0.5Sb1.5Te3 nanopillars array film is about 3.83 μW cm−1 K−2 at T = 475 K. Highly oriented (Bi,Sb)2Te3 nanocrystalline films with tuned electronic transport properties have potentials in thermoelectric devices.

Polyhydroxyalkanoates (PHAs) can be produced by microorganisms from renewable resources and are regarded as promising bioplastics to replace petroleum-based plastics. A medium-chain-length PHAs (mcl-PHA)-producing strain Pseudomonas mendocina NK-01 was isolated previously by our lab and its whole-genome sequence is currently available. Morphology engineering of manipulating cell morphology-related genes has been applied for enhanced accumulation of the intracellular biopolymer short-chain-length PHAs (scl-PHA). However, it has not yet been reported to improve the yield of mcl-PHA by morphology engineering so far. In this work, several well-characterized cell morphology-related genes, including the cell fission ring (Z-ring) location genes minCD, peptidoglycan degradation gene nlpD, actin-like cytoskeleton protein gene mreB, Z-ring formation gene ftsZ, and FtsZ inhibitor gene sulA, were intensively investigated for their impacts on the cell morphology and mcl-PHA accumulation by gene knockout and overexpression in P. mendocina NKU, a upp knockout mutant of P. mendocina NK-01. For a minCD knockout mutant P. mendocina NKU-∆minCD, the average cell length was obviously increased and the mcl-PHA production was improved. However, the nlpD knockout mutant had a shorter cell length and lower mcl-PHA yield compared with P. mendocina NKU. Overexpression of mreB in P. mendocina NKU resulted in spherical cells. When ftsZ was overexpressed in P. mendocina NKU, the cell division was accelerated and the mcl-PHA titer was improved. Furthermore, mreB, ftsZ, or sulA was overexpressed in P. mendocina NKU-∆minCD. Consequently, the mcl-PHA titers were all increased compared with P. mendocina NKU-∆minCD carrying the empty vector. The multiple fission pattern was finally achieved in ftsZ-overexpressing NKU-∆minCD. In this work, improved production of mcl-PHA in P. mendocina NK-01 has been achieved by morphology engineering. This work provides an alternative strategy to enhance mcl-PHA accumulation in mcl-PHA-producing strains.

As a tellurium- and lead-free compound, Cu3SbSe4 is a promising thermoelectric material with relatively high Seebeck coefficient and low thermal conductivity. Here, an effective strategy of weakening p–d hybridization was proposed and demonstrated to enhance the thermoelectric properties for Cu3SbSe4via Ag substitution. This strategy performs a multiple role in high thermoelectric performance, boosting both maximum and average ZT: (1) increase the hole concentration due to the weakened Cu–Se bonding, (2) enlarge the energy gap Eg, putting off the bipolar diffusion, (3) increase the density of states effective mass, and (4) reduce the lattice thermal conductivity mainly due to the large strain fluctuations. As a consequence, a peak ZT ∼ 0.9 at 623 K and a high average ZT above 0.5 for the range 298–623 K can be achieved in a Cu2.85Ag0.15SbSe4 sample. This study provides a new strategy of softening p–d hybridization to boost the thermoelectric performance of Cu3SbSe4 by the synergistic regulation of charge carrier and phonon transports, which is also a meaningful guidance to achieve high thermoelectric performance in other copper-based chalcogenides.

Although solar-driven water evaporation has made extraordinary progress for fresh water generation, great challenges still remain in the mass production of photothermal materials, such as low efficiency and stability, for solar-driven highly corrosive water evaporation. The commercial black sponge has the merits of full sunlight absorbability and robust corrosion resistance. Herein, we treated the commercial black sponge with nitric acid to make it superhydrophilic for efficient water evaporation from not only seawater but also corrosive solutions. The superhydrophilic sponge demonstrates a seawater evaporation rate of 2.72 kg m−2 h−1 under simulated 1 sun irradiation, 7.7 times higher than that of the corresponding pure seawater evaporation and exceeding most of the photothermal materials. More importantly, the superhydrophilic sponge displays photothermal water evaporation performances in 0.5 M H2SO4 and 1 M NaOH with stable 2.53 and 2.22 kg m−2 h−1 water evaporation rates, respectively, exhibiting the record water evaporation rates from highly corrosive solutions. We found that the superhydrophilicity of commercial sponges led to a decrease in the latent heat of water evaporation from 2444 to 1081 kJ kg−1, thereby boosting the water evaporation rate. Therefore, superhydrophilic black sponges have great potential for wide industrial applications such as seawater desalination, salt production, brine management and water purification on a large scale.

MoS2 has attracted extensive attention as the basic configuration of optoelectronic systems because of its outstanding optical and electronic properties. Although high performance MoS2-based photodetectors have been realized by many groups, these studies are still in their initial stages of research, and more importantly, the usual photocurrent or photovoltage signals are fundamentally susceptible, thus seeking novel structures or working principle devices becomes more fascinating. Here, the MoS2/Si heterojunction is prepared with a vertically standing nanoplate structure and we exploit it as a photovoltage, photocurrent and photoresistance-based multifunctional self-powered position sensitive detector (PSD). The PSD exhibits unprecedented performance with very high sensitivity (391.1 mV mm−1, 285.2 μA mm−1, and 21.61 KΩ mm−1 for photovoltage, photocurrent and photoresistance responses, respectively), excellent linearity (nonlinearity

The countries along the 21st-Century Maritime Silk Road (MSRCs) are important geo-economic spaces for China. The implementation of the Belt and Road initiative is drawing a new geo-economic network of the Maritime Silk Road. Based on trade and investment flows, this study uses social network analysis to examine the characteristics and structure of trade and investment networks between China and the MSRCs. The results show that the MSRCs’ trade network is approximately an irregular quadrilateral, the node weighted degree distribution follows the law of long-tail distribution, and the trade network has shifted from the tripartite confrontation of China, Japan, and South Korea to China’s single-core dominance. The MSRCs’ trade group has changed greatly, and the trade cohesion of China, Japan, and South Korea is strong. The MSRCs’ investment network is not fully developed and the network connections are sparse. China, Japan, and Singapore are its core nodes. The weight degree of the MSRCs’ investment inflow network first increased and then decreased, and the weight degree of the MSRCs’ investment outflow network increased. The MSRCs’ investment network followed the “core-peripheral” structure. The cohesive subgroup of the investment inflow network did not have significant regional characteristics, and the cohesion of the core subgroups in the MSRCs’ investment outflow network was strong. To promote the development of geo-economic relations between China and the MSRCs, China should focus on regional powers, upgrade the investment network of MSRCs, and implement differentiated geo-economic cooperation strategies.