Solar-to-chemical production by photosynthetic biohybrid systems does not only take advantage of the broadband light efficiency of semiconductor but also utilize highly specific biological catalytic ...power in living organism. Herein, we demonstrate a tandem inorganic-biological hybrid by combining AglnS2/In2S3 and a facultative anaerobic bacterium, Escherichia coli, for biological H2 production. The AglnS2/In2S3@E. coli hybrid system harvests light energy and makes use of anaerobically synthesized bacterial endogenous Ni-Fe-hydrogenase and photo-generated electrons from AglnS2/In2S3 hybrid for enhanced H2 evolution efficiency. A highly quantum efficiency (QE) of 3.3% at 720 nm for H2 production is achieved from the hybrid system, exceeding those of many reported photoheterotrophic bacteria. This biomimetic approach may provide a guidance for the interfacing of hybrid semiconductors with living organisms for solar-to-chemical production.
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•A tandem inorganic-biological hybrid is obtained for biological H2 production.•AglnS2/In2S3 hybrid harvests light energy to enhance H2 production by E. coli.•E. coli makes use of Ni-Fe-hydrogenase and electrons for enhanced H2 evolution.•A highly quantum efficiency of 3.3% at 720 nm for H2 production is achieved.
Intramuscular fat (IMF) is closely related to the tenderness, marbling, juiciness, and flavor of meat. We used a combined transcriptome and metabolome analysis to investigate the molecular mechanisms ...underlying phenotypic variation among Qinchuan cattle.
The IMF content was relatively high in the meat of Qinchuan cattle bulls and differed among muscle locations, namely the high rib (15.86%), ribeye (14%), striploin (10.44%), and tenderloin (8.67%). CCDC80 and the HOX gene cluster may regulate intramuscular adipose tissue deposition. Moreover, erucic acid (EA) was found to be the main metabolite in Qinchuan beef cattle, with a high concentration in IMF. The deposition of IMF could be regulated by the metabolic pathway for unsaturated fatty acids involving EA and the ACOX3, HACD2, and SCD5 genes. In addition, differentially expressed genes and metabolites were enriched in three major KEGG pathways: purine metabolism, pyrimidine metabolism, and the metabolism of glycine, serine, and threonine.
We identified a significant metabolite, EA, with variation in IMF. Its closely related genes, ACOX3, HACD2, and SCD5, co-regulate the metabolism of unsaturated fatty acids, ultimately affecting the accumulation of intramuscular adipose tissue in Qinchuan cattle. Consequently, Qinchuan cattle are an elite cultivar for high-quality beef production and have great potential for breeding.
Noble metal nanostructures are grown inside hollow mesoporous silica microspheres using “ship‐in‐a‐bottle” growth. Small Au seeds are first introduced into the interior of the hollow microspheres. Au ...nanorods with synthetically tunable longitudinal plasmon wavelengths and Au nanospheres are obtained through seed‐mediated growth within the microspheres. The encapsulated Au nanocrystals are further coated with Pd or Pt shells. The microsphere‐encapsulated bimetallic core/shell nanostructures can function as catalysts. They exhibit high catalytic performance and their stability is superior to that of the corresponding unencapsulated core/shell nanostructures in the catalytic oxidation of o‐phenylenediamine with hydrogen peroxide. Therefore, these hollow microsphere‐encapsulated metal nanostructures are promising as recoverable and efficient catalysts for various liquid‐phase catalytic reactions.
Different monometallic Au and bimetallic Au‐cored nanostructures are grown using a “ship‐in‐a‐bottle” technique in hollow mesoporous silica microspheres. The microsphere‐encapsulated Au nanorod core/Pt shell nanostructures exhibit both high catalytic performance and superior recyclability in the oxidation reaction of o‐phenylenediamine with hydrogen peroxide, while the conversion percentage in the presence of the corresponding unencapsulated nanostructures decreases rapidly with the recycle number.
Ruthenium oxide/graphene (RuO2/GR) hybrid materials for high performance electrochemical capacitor have been prepared by a solution-phase assembly technology between RuO2 nanosheets and GR nanosheets ...at room temperature. The high dispersion of RuO2 and GR nanosheets maintains a high structural stability for the hybrid material, and causes an obvious synergistic effect between the RuO2 and GR nanosheets. A specific capacitance of 479 F g-1 has been obtained for the hybrid material with RuO2 mass content of 40% (abbreviated as RuGR46), and a high specific capacitance of 998 F g-1 obtained for RuO2 in the electrode. The utilization of RuO2 in the RuGR46 hybrid material increases by adding GR, and the capacitance of RuGR46 is quite comparable to that of the pristine RuO2.xH2O while 60 wt% of RuO2 can be saved. A symmetrical electrochemical capacitor based on the RuGR46 electrode is assembled with 0.5 mol L-1 H2SO4 solution as the electrolyte in a voltage of 0-1.2 V. It can give a high energy density of 20.28 Wh kg-1 at a power density of 600 W kg-1. Moreover, it presents a high power density (14.03 Wh kg-1 at 12 kW kg-1) and excellent cycle performance.
Gold nanocrystals are dispersed uniformly in poly(dimethylsiloxane) to produce a plasmonic composite. The composite can be readily used to fabricate microfluidic channels. An efficient optical ...heating approach on the microfluidic chips made of the composite is realized on the basis of plasmon‐enabled photothermal conversion. A fluid flow switch based on the plasmonic heating is also demonstrated.
Users' feedback information as the ground-truth has attracted a lot of attention in recommender systems. However, the feedback that could be contaminated by users' misoperations or malicious ...operations is probably not true in real scenarios. This work aims to develop a technique based on an improved Bayesian personalized ranking (BPR), called adversarial training-based mean Bayesian personalized ranking (AT-MBPR). In this method, we divide the feedback information into three categories based on the mean Bayesian personalized ranking (MBPR), then gain the implicit feedback from the mean and non-observed items of each user, following which, adversarial perturbations are added on the embedding vectors of the users and items by playing a minimax game to reduce the noise. The experiments demonstrate in five datasets that our approach outperforms the traditional BPR methods and state-of-the-art methods used for the recommendation. Our implementation is available at: https://github.com/HanXia001/Adversarial-Training-based-Mean-BPR-for-Recommender.
The intramuscular fat (or marbling fat) content is an essential economic trait of beef cattle and improves the flavor and palatability of meat. Several studies have highlighted the correlation ...between long non-coding RNAs (lncRNAs) and intramuscular fat development; however, the precise molecular mechanism remains unknown. Previously, through a high-throughput sequencing analysis, we found a lncRNA and named it a long non-coding RNA BNIP3 (lncBNIP3). The 5' RACE and 3' RACE explored 1945 bp total length of lncBNIP3, including 1621 bp of 5'RACE, and 464 bp of 3'RACE. The nucleoplasmic separation and FISH results explored the nuclear localization of lncBNIP3. Moreover, the tissue expression of lncBNIP3 was higher in the longissimus dorsi muscle, followed by intramuscular fat. Furthermore, down-regulation of lncBNIP3 increased the 5-Ethynyl-2'- deoxyuridine (EdU)-EdU-positive cells. The flow cytometry results showed that the number of cells in the S phase was significantly higher in preadipocytes transfected with si-lncBNIP3 than in the control group (si-NC). Similarly, CCK8 results showed that the number of cells after transfection of si-lncBNIP3 was significantly higher than in the control group. In addition, the mRNA expressions of proliferative marker genes CyclinB1 (CCNB1) and Proliferating Cell Nuclear Antigen (PCNA) in the si-lncBNIP3 group were significantly higher than in the control group. The Western Blot (WB) results also showed that the protein expression level of PCNA transfection of si-lncBNIP3 was significantly higher than in the control group. Similarly, the enrichment of lncBNIP3 significantly decreased the EdU-positive cells in the bovine preadipocytes. The results of flow cytometry and CCK8 assay also showed that overexpression of lncBNIP3 inhibited the proliferation of bovine preadipocytes. In addition, the overexpression of lncBNIP3 significantly inhibited the mRNA expressions of CCNB1 and PCNA. The WB results showed that the overexpression of lncBNIP3 significantly inhibited the expression of the CCNB1 protein level. To further explore the mechanism of lncBNIP3 on the proliferation of intramuscular preadipocytes, RNA-seq was performed after interference with si-lncBNIP3, and 660 differentially expressed genes (DEGs) were found, including 417 up-regulated DEGs and 243 down-regulated DEGs. The KEGG pathway analysis showed that the cell cycle was the most significant pathway for the functional enrichment of DEGs, followed by the DNA replication pathway. The RT-qPCR quantified the expression of twenty DEGs in the cell cycle. Therefore, we speculated that lncBNIP3 regulated intramuscular preadipocyte proliferation through the cell cycle and DNA replication pathways. To further confirm this hypothesis, the cell cycle inhibitor Ara-C was used to inhibit DNA replication of the S phase in intramuscular preadipocytes. Herein, Ara-C and si-lncBNIP3 were simultaneously added to the preadipocytes, and the CCK8, flow cytometry, and EdU assays were performed. The results showed that the si-lncBNIP3 could rescue the inhibitory effect of Ara-C in the bovine preadipocyte proliferation. In addition, lncBNIP3 could bind to the promoter of cell division control protein 6 (CDC6), and down-regulation of lncBNIP3 promoted the transcription activity and the expression of CDC6. Therefore, the inhibitory effect of lncBNIP3 on cell proliferation might be understood through the cell cycle pathway and CDC6 expression. This study provided a valuable lncRNA with functional roles in intramuscular fat accumulation and revealed new strategies for improving beef quality.
Sensitive and specific detection of nucleic acids or proteins, which act as biomarkers, is of great importance in disease diagnosis. By combing the concept and operation of an endonuclease-assisted ...target-responsive amplification method and peroxidase-mimic DNAzyme generated by terminal deoxynucleotidyl transferase (TdT), a novel and facile colorimetric biosensor was developed for DNA and protein. Target DNA and thrombin were chosen as representative biomolecules. The production of cleavage fragments can only be triggered by specific target binding and the following nicking process, which do not occur spontaneously. In the signal collection part, numerous guanine-rich DNA were produced through the prolongation of cleavage fragments by TdT and formed highly effective DNAzyme with hemin. In this novel amplification method, we succeeded in realizing sensitive and specific detection of target DNA and thrombin. Under optimal conditions, target DNA can be detected as low as 1 pM, and thrombin with a detection limit of 100 pM. The method also proves the potential versatility and feasibility of TdT-generated DNAzyme in various bio-analyses.
An asymmetrical electrochemical capacitor (graphene/MCNT/MnO2//graphene/MCNT) has been assembled using aqueous Na2SO4 solution as electrolyte. The asymmetrical electrochemical capacitor with high ...energy density can cycle reversibly in a cell potential of 0–2.0V and gives excellent cycling performance. Display omitted
► GR/MCNT/MnO2 hybrid material within a potential window of 0–1.1V vs. SCE has been prepared. ► An asymmetric electrochemical capacitor working at 2.0V in aqueous medium is assembled based on the GR/MCNT/MnO2 and GR/MCNT. ► The asymmetric electrochemical capacitor exhibits high energy density and excellent cycle performance.
Graphene/multiwall carbon nanotubes/MnO2 (GR/MCNTs/MnO2) hybrid material with a specific capacitance of 126Fg−1 within a potential window of 0–1.1V vs. saturated calomel electrode has been synthesized by a simple redox reaction between graphene/multiwall carbon nanotubes (GR/MCNTs) and KMnO4 at room temperature. The morphology and structure of the obtained material are examined by XRD, SEM and TEM. The electrochemical properties are characterized by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The mass percentage of MnO2 with layered structure is 37% in the hybrid material. An asymmetrical electrochemical capacitor (EC) is assembled using GR/MCNT/MnO2 hybrid material as positive electrode and GR/MCNT material as negative electrode, respectively. The electrochemical properties of the two electrodes and the asymmetrical EC are investigated in 1molL−1 Na2SO4 aqueous electrolyte. The asymmetrical EC can cycle reversibly in a cell potential of 0–2.0V and gives a high energy density of 28.33Whkg−1, which is much higher than those of symmetrical ECs based on GR/MCNT/MnO2 (6.20Whkg−1) and GR/MCNT (3.92Whkg−1). Moreover, the asymmetrical EC presents a high power density (5kWkg−1 at 13.33Whkg−1) and excellent cycling performance of 83% retention after 2500 cycles.
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