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The contribution of cold water aquaculture for the world fish production is significant. Although sturgeon farming is an important part of China's cold water aquaculture industry, its production is less compared with the current potentiality of the country. There are many reasons for the lower production of cold water fish farming including feed and disease. The aim of the present study was to investigate the effect of a paraprobiotic and postbiotic feed supplement (Herpes Worry Free or HWF™) on the growth, feeding efficiency and gut microbiota balance of hybrid sturgeon. Besides, the effect of sturgeon gut microbiota fed on the diet supplemented with HWF™ on the expression of growth promoter, and immune regulatory genes of germ free (GF) zebrafish was evaluated. Sturgeon were fed for three weeks with HWF™ supplemented or basal diet. At the end of the experiment gut content of sturgeon, fed on either experimental diet was transferred and colonized to GF zebrafish. Sturgeon fed with HWF™ supplemented diet showed significantly higher weight gain rate and lower feed conversion ratio (FCR) as compared with the control (P 0.05). Compared with the control group, the relative abundance of Firmicutes, were significantly higher in the HWF™ group (P 0.05), whereas Proteobacteria, Actinobacteria and Chlamydiae were significantly higher in the control group (P 0.05). Furthermore, at the genus level Clostridium (64.50 ± 5.99%) and Lactococcus (29.5 ± 3.05%) were the most dominant gut bacteria in the HWF™ group and the control group of sturgeon, respectively. The expression of genes related to growth, inflammation and non-specific immunity was significantly upregulated in GF zebrafish colonized with gut microbiota of HWF™ sturgeon group. In conclusion, HWF™ played significant role in growth, feed efficiency and modulation of gut microbiota of sturgeon. The gut microbiota of sturgeon fed on the diet supplemented with HWF™ upregulated the expression of genes related to growth, inflammation and non-specific immunity in GF zebrafish model.

Biological modification of natural products is an important approach to improve the pharmacological properties. 4′-d-β-Demethylepipodophyllotoxin (4′-d-β-DMEP), a typical natural lignin, is used as the aglycon of topoisomerase inhibitor etoposide (VP-16). In this study, 4′-d-β-DMEP was isomerized into the novel product 4′-d-α-DMEP with 43.09% conversion by P. purpurogenum ACCC 32170. 4′-d-α-DMEP was largely produced extracellularly in the late fermentation stage, which was accompanied with the decrease of dry cell weight and the increase of culture pH. A constitutively expressed cytosolic enzyme was involved in the transformation and functioned when culture pH ranged from 7.0–10.0. The IC50 value of 4′-d-α-DMEP was around 0.80 μM against tumor cells MCF-7, which was significantly reduced by 11.27 and 17.34 times than 4′-d-β-DMEP (i.e., 9.82 μM) and VP-16 (i.e., 14.67 μM). This study provided the novel podophyllotoxin derivative with higher anti-tumor activity and microbial transformation process, which would promote transferring lignans into the clinic trial.

Hepatitis-hydropericardium syndrome (HHS) caused by hypervirulent fowl adenovirus 4 (FAdV-4) have been causing great economic losses to Chinese poultry industry since 2015. Elucidation of the pathogenesis of FAdV-4 will lay solid foundation for developing attenuated FAdV-4 vaccine and vaccine vector. Our previous study has demonstrated that the increased virulence of hypervirulent FAdV-4 was associated with fiber-2 and hexon genes. However, the roles of fiber-1 and penton in virulence of FAdV-4 have never been elucidated. To further investigate the roles of the major structural proteins fiber-1 and penton in the virulence of hypervirulent FAdV-4, the fiber-1- and penton-replaced mutant viruses were constructed based on the FAdV-4 infectious clones of hypervirulent strain HNJZ using Redαβ recombineering techniques. The pathogenicity of the rescued viruses was evaluated in 3-week-old SPF chickens. Chickens infected with the rescued recombinant viruses carrying the fiber-1 or penton base gene from a nonpathogenic strain ON1 developed similar clinical signs to the natural hypervirulent FAdV-4 infection, including HHS-indicative gross lesions and histopathological changes in sick/dead chickens. Our results suggested that the increased virulence of hypervirulent FAdV-4 was independent of fiber-1 and penton. The detailed pathogenesis of FAdV-4 and the roles of fiber-1 and penton in the viral replication and infection process need to be further explored.

High-performance thin piezoelectric ceramic sheets are crucial for improving the properties of stacked actuators. However, few studies have been conducted on the preparation of thin sheets of KNN-based lead-free ceramics. In this study, 0.9625(K0.48Na0.52) (Nb0.6Sb0.4)O3-0.0375Bi0.5(Na0.82K0.18)0.5ZrO3 (KNNS-BNKZ) ceramics were prepared by a traditional solid-state reaction method and then ground to thicknesses of 0.5, 0.4, and 0.3 mm. X-ray diffraction patterns, scanning electron microscope images, temperature-dependent dielectric constants, and the piezoelectric constants d33 were measured. In addition the hysteresis loops and butterfly strain curves were recorded. The results show that the phase of the ceramics changed from tetragonal to orthorhombic during the grinding process because of grinding stress, and the piezoelectric properties of the ceramics (i.e., d33) increased from 198 to 275 PC/N. More importantly, Pr increased, Ec decreased, and a high strain of 0.125% was achieved under an electric field of 14 kV/cm for the 0.5-mm-thick ceramic with d33 = 268 PC/N. It is concluded that grinding not only can reduce the thicknesses of ceramic sheets but can also improve their electromechanical properties, which opens up a new path for employing KNN-based ceramics in piezoelectric stack actuators.

Abnormal functional connectivity (FC) within the default model network (DMN) in schizophrenia has been frequently reported in previous studies. However, traditional FC analysis was mostly linear correlations based, with the information on nonlinear or temporally lagged brain signals largely overlooked. Fifty-five first-episode drug-naïve schizophrenia (FES) patients and 53 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging scanning. The DMN was extracted using independent component analysis. Recurrence quantification analysis was used to measure the duration, predictability, and complexity of the periodic processes of the nonlinear DMN time series. The Mann‒Whitney U test was conducted to compare these features between FES patients and HCs. The support vector machine was applied to discriminate FES from HCs based on these features. Determinism, which means predictability of periodic process activity, between the ventromedial prefrontal cortex (vMPFC) and posterior cingulate and between the vMPFC and precuneus, was significantly decreased in FES compared with HCs. Determinism between the vMPFC and precuneus was positively correlated with category fluency scores in FES. The classifier achieved 77% accuracy. Our results suggest that synchronized periodicity among DMN brain regions is dysregulated in FES, and the periodicity in BOLD signals may be a promising indicator of brain functional connectivity.

The cryptic secondary metabolite biosynthetic gene clusters (BGCs) far outnumber currently known secondary metabolites. Heterologous production of secondary metabolite BGCs in suitable chassis facilitates yield improvement and discovery of new-to-nature compounds. The two juxtaposed conventional model microorganisms, Escherichia coli, Saccharomyces cerevisiae, have been harnessed as microbial chassis to produce a bounty of secondary metabolites with the help of certain host engineering. In last decade, engineering non-model microbes to efficiently biosynthesize secondary metabolites has received increasing attention due to their peculiar advantages in metabolic networks and/or biosynthesis. The state-of-the-art synthetic biology tools lead the way in operating genetic manipulation in non-model microorganisms for phenotypic optimization or yields improvement of desired secondary metabolites. In this review, we firstly discuss the pros and cons of several model and non-model microbial chassis, as well as the importance of developing broader non-model microorganisms as alternative programmable heterologous hosts to satisfy the desperate needs of biosynthesis study and industrial production. Then we highlight the lately advances in the synthetic biology tools and engineering strategies for optimization of non-model microbial chassis, in particular, the successful applications for efficient heterologous production of multifarious complex secondary metabolites, e.g., polyketides, nonribosomal peptides, as well as ribosomally synthesized and post-translationally modified peptides. Lastly, emphasis is on the perspectives of chassis cells development to access the ideal cell factory in the artificial intelligence-driven genome era. © 2022 Elsevier Inc. National Natural Science Foundation of China; Natural Science Foundation of Shandong Province; National Key Research and Development Program of China: This work was supported by the National Key R&D Program of China (Grant nos. 2021YFC2100500 , 2019YFA0905700 ), National Natural Science Foundation of China (Grant nos. 32070060 , 32161133013 ), Shandong Provincial Natural Science Foundation (Grant no. ZR2019JQ11 , ZR2019ZD18 ).

The mammalian gut has a remarkable abundance of microbes. These microbes have strong potential to biosynthesize distinct metabolites that are promising drugs, and many more bioactive compounds have yet to be explored as potential drug candidates. These small bioactive molecules often mediate important host-microbe and microbe-microbe interactions. In this review, we provide perspectives on and challenges associated with three mining strategies - culture-based, (meta)genomics-based, and metabolomics-based mining approaches - for discovering natural products derived from biosynthetic gene clusters (BGCs) in mammalian gut microbiota. In addition, we comprehensively summarize the structures, biological functions, and BGCs of these compounds. Improving these techniques, including by using combinatorial approaches, may accelerate drug discovery from gut microbes.

Pseudomonas protegens CHA0 is a well-characterized, root-colonizing bacterium with broad-spectrum biocontrol ability. Therefore, it has a great potential to curb plant diseases and to partly replace synthetic chemical pesticides that are harmful to humans. Here, we obtained the multifunctional mutant CHA0-ΔretS-Nif via Red/ET recombineering technology. After deletion of the retS gene and integration of the nitrogen-fixing gene island (Nif) into the CHA0 genome, the resulting mutant, CHA0-ΔretS-Nif, manifested improved both bactericidal activity and biological nitrogen-fixation function. A pot experiment of Arabidopsis thaliana indicated that the strain CHA0-ΔretS-Nif promoted plant growth via expressing several secondary factors, such as the antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) and nitrogenase. In order to grow this biocontrol strain at an industrial level, the growth conditions in a 1 L continuous-flow fermenter were optimized to 28 °C, pH of 7.0, and 600 rpm. Moreover, growth experiments in a 5 L fermenter with these optimal growth conditions yielded the maximum cell density, providing vital insights for the industrialization and large-scale fermentation of P. protegens CHA0 for further applications. CHA0-ΔretS-Nif possesses both bactericidal and nitrogen-fixation activities and thus could be used as a biological agent to enhance crop production.

The efficient utilization of solar energy for environmental cleaning has attracted great attention, where the key is to efficiently harvest the visible and near-infrared (NIR) light which occupies approximately 95% of the solar light energy. Recently, black phosphorus (BP), as a new staring 2D material, has been extensively studied as photocatalytic materials due to its broad light absorption and tunable bandgap. Herein, we report a novel ternary nanocomposite, BP-Ag/TiO2, prepared through controlled deposition of Ag clusters on the surface of TiO2 nanocrystals and then incorporated to BP nanosheets. The BP-Ag/TiO2 nanocomposite has shown excellent photocatalytic activity towards the degradation of methylene blue (MB) under visible and NIR light irradiation. About 100% and even 25% of MB was degraded in 85 min under >420 nm and >780 nm irradiation, respectively. The enhanced photocatalytic activity of BP-Ag/TiO2 nanocomposite was mainly ascribed to the sensitization of BP nanosheets by fully harvest of solar light and high electron-hole separation efficiency. We believe that the BP-Ag/TiO2 nanocomposite will be an effective photofunctional material in full-spectrum solar energy conversion and opens up a new door for the development of solar light driven photocatalysts for the remediation of environmental pollution.

Microplastic (MPs) is a new type of environmental pollutant that has been widely detected in recent years. It is one of the main environmental problems faced by the global ecosystem and has attracted widespread attention. However, few studies have focused on the occurrence and distribution of MPs in agroecosystems. Therefore, Qinghai Province, a typical northwest region of China, was selected as the research area to study the distribution characteristics of MPs in agricultural soils in the low-altitude areas. The results indicated that MPs were detected in all soil samples. The abundance of MPs in agricultural soils in Qinghai Province ranged from 240 to 3660 items·kg

As an emerging resource, Gram-negative Burkholderia bacteria were able to produce a wide range of bioactive secondary metabolites with potential therapeutic and biotechnological applications. Genome mining has emerged as an influential platform for screening and pinpointing natural product diversity with the increasing number of Burkholderia genome sequences. Here, for genome mining of potential biosynthetic gene clusters (BGCs) and prioritizing prolific producing Burkholderia strains, we investigated the relationship between species evolution and distribution of main BGC groups using computational analysis of complete genome sequences of 248 Burkholderia species publicly available. We uncovered significantly differential distribution patterns of BGCs in the Burkholderia phyla, even among strains that are genetically very similar. We found various types of BGCs in Burkholderia, including some representative and most common BGCs for biosynthesis of encrypted or known terpenes, non-ribosomal peptides (NRPs) and some hybrid BGCs for cryptic products. We also observed that Burkholderia contain a lot of unspecified BGCs, representing high potentials to produce novel compounds. Analysis of BGCs for RiPPs (Ribosomally synthesized and posttranslationally modified peptides) and a texobactin-like BGC as examples showed wide classification and diversity of RiPP BGCs in Burkholderia at species level and metabolite predication. In conclusion, as the biggest investigation in silico by far on BGCs of the particular genus Burkholderia, our data implied a great diversity of natural products in Burkholderia and BGC distributions closely related to phylogenetic variation, and suggested different or concurrent strategies used to identify new drug molecules from these microorganisms will be important for the selection of potential BGCs and prolific producing strains for drug discovery.

A novel ternary nanohybrid comprising Ag nanoparticles anchored on black phosphorus nanosheets (BPNS) supported on the surface of graphene oxide (GO) has been synthesized for the first time. UV–Vis spectra and X-ray photoelectron spectroscopy results revealed that BPNS with highly active P atoms on its surface served as a strong reductant to reduce Ag precursor and the emerging Ag atoms were consequently deposited on its surface. The Ag-BPNS/GO nanohybrid showed excellent photocatalytic activity towards the degradation of methylene blue under solar light irradiation. Broad spectrum response of BPNS, effective trapping of the electrons of Ag nanoparticles and high stability of Ag-BPNS on GO surface contributed the enhanced photocatalytic performance. A plausible mechanism has been proposed to explain the enhanced photocatalytic performance of the Ag-BPNS/GO nanohybrid.

Reactive oxygen species (ROS) are initially considered to be toxic by-products of aerobic metabolism. However, accumulating evidence has shown that ROS also act as key regulators for the progression of several basic biological processes. Recent studies highlight the key role of ROS in root and shoot stem cell niche maintenance.

The hysteresis of piezoelectric ceramics plays an important role in determining errors when they are applied in actuators. However, the relationships between the hysteresis characteristic, preparation process of the piezoelectric ceramic, and displacement error of the actuator have rarely been systematically studied. In this study, 0.9625(K 0.48 Na 0.52 )(Nb 0.6 Sb 0.4 )O 3 -0.0375Bi 0.5 (Na 0.82 K 0.18 ) 0.5 ZrO 3 (KNNS-BNKZ) ceramics were prepared via a solid-state reaction and sintered at 1140 °C, 1160 °C, and 1180 °C. Subsequently, the influence of sintering temperatures on the phase composition, microstructure, piezoelectric properties, and ferroelectric properties of the samples was studied. Furthermore, the factors affecting the hysteresis characteristics were systematically analyzed. The results showed that the ceramic sintered at 1140 °C possessed the smallest hysteresis with H max = 25% owing to its phase composition and microstructure. Additionally, linear regression of the displacement versus voltage was carried out and the corresponding equations were obtained. Finally, the hysteresis model of the ceramic sintered at 1140 ℃ was established and its error was determined to be less than 1.81%, which renders these ceramics suitable for application in high-precision actuators.

Objective To retrospectively review the clinicopathologic features and computed tomography (CT) and magnetic resonance imaging (MRI) findings of lumbosacral intraspinal paragangliomas (PGLs). Methods Thirteen patients with surgically and pathologically confirmed lumbosacral intraspinal PGLs were enrolled. Their clinicopathologic data and imaging findings were retrospectively reviewed. Results Ten male and 3 female patients with a median age of 43 years (range, 36–74 years) were included. CT or MRI showed a well-defined (n = 13), oval (n = 10), or striated (n = 3) mass with heterogeneous (n = 6) or homogeneous density/signal intensity (n = 7). The lesions appeared isointense (n = 13) and mildly hyperintense (n = 13) on T1-weighted and T2-weighted MRI, respectively. On enhanced CT/MRI, markedly heterogeneous (n = 6) and homogeneous (n = 7) enhancement patterns were observed. The tadpole sign was observed in 9 cases. Systolic and diastolic blood pressure were higher before than after surgery (PSBP = 0.002 and PDBP = 0.001). Both systolic and diastolic blood pressure were reduced to normal after surgery. No recurrence or metastatic disease was found during the follow-up period. Conclusions Lumbosacral intraspinal PGLs should be considered when a mass appears as well defined or oval, and when a striated solitary homogeneous or heterogeneous mass is characterized by a tadpolelike appearance with a marked enhancement pattern. The fluctuation of blood pressure before and after surgery is an interesting clinical feature of lumbosacral intraspinal PGLs.

Plesiomonas shigelloides is an important fish pathogen that causes significant losses in aquaculture. Phage therapy is a new approach to overcome the problem of multidrug-resistant bacteria. Herein, a virulent phage of P. shigelloides was isolated from the intestines of grass carp. This phage belongs to the Siphoviridae family and was designated PSP01. The optimal multiplicity of infection of PSP01 was 1 with a latent period of 30 min and a lytic period of 140 min. Good activity was observed over a wide range of temperatures (-20 °C–50 °C), pH values (3–12), and NaCl concentrations (0.1–3.5%). The phage PSP01 lysis cassette is composed of 3 genes, HolPSP, LysPSP-1 and LysPSP-2. Expression of HolPSP or LysPSP-2 in Escherichia coli resulted in bacterial lysis, and a synergistic effect was observed when the HolPSP and LysPSP-1 proteins were co-expressed. In-frame deletion uncovered an important role of the transmembrane domain (TMD) in HolPSP and the signal peptide (SP) in LysPSP-2 for bacterial lysis function. The protective effects of phage PSP01 were investigated by intraperitoneal injection into grass carp infected with P. shigelloides, showing a 33.3% increase in the survival rate of the infected grass carp. Pathological analysis of the spleens from the infected grass carp revealed alleviation of the pathological symptoms. In conclusion, isolation and bacterial lysis investigations of phage PSP01 provide a new tool for the control of fish pathogens and possesses potential for aquaculture applications.

Two novel tetradentate platinum (II) 3,6-substituted salophen complexes of Pt-2 and Pt-3 were synthesized and characterized, in which the substituted group is a donor (D) unit of 4,4′-di(tert-butyl)triphenylamine (ButTPA) for Pt-2 and a donor-acceptor (D-A) framework of ButTPA and benzothiadiazole (BT) for Pt-3. Their thermal, optophysical, electrochemical and electroluminescent properties were primarily investigated. It is found that the emission for this type of tetradentate platinum (II) complexes is tuned from deep red to near infrared by appending D-A framework under photo-excitation. As a result, Pt-3 presented a significant near infrared electroluminescence peaked at 703 nm in its doped polymer light-emitting devices (PLEDs). The maximum external quantum efficiency of 0.88% is observed in the Pt-3 doped PLEDs using a blend of poly(vinylcarbazole) and 1,3-bis(5-(4-(tert-butyl)phenyl)-1,3,4-oxadiazol-2-yl) benzene as the host matrix. Our work indicates that appending D-A framework into tetradentate Pt(II) salophen complex is a useful strategy to get high-performance near infrared emission for this type of tetradentate Pt (II) complexes.

Two novel tetradentate bis-cyclometalated platinum (IV) complexes of TPA-2q-PtCl2 and 3TPA-2q-PtCl2 with CˆN*NˆC cyclometalated ligands and two coordinated chlorine atoms were synthesized and characterized. The crystal structure of TPA-2q-PtCl2 shows a trans-form irregular octahedral geometry by measurement of single-crystal X-ray diffraction, where two CˆN coordination moieties are twisted and two chlorine atoms are located on both sides of platinum atom. A medium absorption band in a range of 450–474 nm is observed, which is assigned to the metal-to-ligand charge-transfer (MLCT) and intramolecular charge transfer (ILCT). And two obvious emission peaks at about 635 and 750 nm are displayed for both platinum (IV) complexes in 2-methyltetrahydrofuran solutions, which originate from the ILCT and MLCT characters to the lowest excited state. Using one of platinum (IV) complexes as a single dopant and a blend of poly(vinylcarbazole) as a host matrix, their single-emissive-layer polymer light-emitting diodes (PLEDs) exhibit an outstanding near-infrared emission with an electroluminescent (EL) peak of 750 nm. The better electroluminescent properties are obtained in the 3TPA-2q-PtCl2 doped devices with an external quantum efficiency of 0.85% and a radiance of 164 μW/cm−2. This is the first reported sample about tetradentate biscyclometalated platinum (IV) complexes used as organic NIR electroluminescent materials for promising application in PLEDs.

A novel type of the benzo[4,5]thieno[2,3- b ]indole (BTI)-terminated small molecules (SMs) with a D′(A-D) 2 framework were synthesized and characterized, i.e. BDT(DPP- 9 -BTI) 2 , BDT(DPP- 8 -BTI) 2 and 2T(DPP- 8 -BTI) 2 , in which the central donor (D′) units are benzodithiene (BDT) and dithiophene (2T), the armed acceptor (A) unit is dithienyl-diketopyrrolopyrrole (DPP), and the terminated donor (D) unit is BTI with different substituted position. For comparison, the SMs with a D-A-D framework, DPP-9-2BTI and DPP-8-2BTI, were also synthesized. The photophysical, electro-chemical, thermal, and photovoltaic properties were preliminary investigated. It is found that the molecular framework and the substituted position of BTI have a significant influence on these properties. The D′(A-D) 2 type SMs exhibited better photovoltaic per-formances than the D-A-D type SMs. Furthermore, the SMs suspending 8-sbstituted BTI displayed better photovoltaic performances than those corresponding SMs suspending 9-sbstituted BTI. The highest power conversion efficiency of 4.80% and a maximum short-circuit current density of 11.91 mA cm −2 were obtained in the solution-processed BDT(DPP- 8 -BTI) 2 -based solar cells using [6,6]-phenyl-C-71-butyric acid methyl ester as acceptor. It indicates that tuning the molecular framework and substituted position of the BTI terminals is an efficient strategy to improve photovoltaic performances for their small molecules.

Microbial fuel cells (MFCs) have attracted great attentions due to their great application potentials, but the relatively low power densities of MFCs still hinder their widespread practical applications. Herein, we report that the current generation in MFCs can be boosted by an order of magnitude, simply by coating a hydrophilic and positively charged ionic liquid polymer (ILP) on carbon cloth (CC) or carbon felt (CF). The ILP coating not only can increase the bacterial loading capacity due to the electrostatic interactions between ILP and bacterial cells, but also can improve the mediated extracellular electron transfer between the electrode and the cytochrome proteins on the outer membrane of Shewanella putrefaciens cells. As a result, the maximum power density of a MFC equipped with the CF-ILP bioanode is as high as 4400±170mWm-2, which is amongst the highest values reported to date. This work demonstrates a new strategy for greatly boosting the current generation in MFCs.

A colorimetric and fluorescent probe L has been designed and synthesized, which bearing the double azine moiety and showing a detection limit of 2.725 × 10−7 M towards Zn2+. Based on the basic recognition mechanism of ESIPT and CHEF effect, the L has high selectivity and sensitivity to only Zn2+ (not Fe3+, Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Cr3+, and Mg2+) within the physiological pH range (pH = 7.0–8.4) and showed a fluorescence switch. Moreover, this detection progress occured in the DMSO/H2O ∼ HEPES buffer (80/20, v/v; pH 7.23) solution which can conveniently used on test strip., Graphical abstract A colorimetric and fluorescent probe L has been designed and synthesized, bearing the double azine moiety and showing a detection limit of 2.725 × 10−7 M towards Zn2+. Based on the basic recognition mechanism of ESIPT and CHEF effect, the probe owes high selectivity and sensitivity to only Zn2+ (not Fe3+, Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Cr3+, and Mg2+) within the physiological pH range (pH = 7.0–8.4) and showed a fluorescence switch. Moreover, this detection progress occur in the DMSO/H2O ∼ HEPES buffer (80/20, v/v; pH 7.23) solution which can conveniently used on test strip, and it can anti interference of others.Image 1

Two novel tetradentate platinum (II) salophen complexes A and B, respectively substituted by dual donor-accepter frameworks of phenazine-triphenylamine in the heads and waists of salophen, were synthesized and characterized. By changing the substituted positions of dual phenazine-triphenylamine units, different optophysical, electrochemical and electroluminescent properties were remarkably observed for the both platinum (II) salophen complexes. Using a blend of poly(vinyl-carbazole) (PVK) and 1,3-bis(5-(4-( tert -butyl) phenyl)-1,3,4-oxadiazol-2-yl)benzene (OXD-7) as host matrix, the platinum (II) salophen complexes A and B exhibited a deep red emission at 653 nm and a near-infrared (NIR) emission at 695 nm in the single-emissive-layer polymer light-emitting devices, respectively. The maximum external quantum efficiency ( EQE ) of 1.36% and highest radiant intensity ( R ) of 45 μ W cm −2 were obtained in the complex B-doped devices, which are 13.6 and 2.6 times of those corresponding values in the complex A-doped devices. It indicates that appending dual donor-accepter frameworks in the heads of salophen is an efficient strategy to achieve NIR emission for their tetradentate platinum (II) complexes.

We report here that poly- o -phenylenediamine as a solid carbon source can be facilely carbonized to produce three-dimensional nitrogen-doped graphene (3DNGN) with the aid of Ni(NO 3 ) 2 powder. In situ formed Ni nanoparticles by decomposition of Ni(NO 3 ) 2 serve as both template and catalyst for the formation of 3DNGN. The 3DNGN with interconnected porous structure and high content of nitrogen doping can ensure large electrolyte-accessible surface area, rapid ion transportation, and fast electron transport, resulting in high electrochemical performance. The 3DNGN shows a high specific capacitance of 312 F g − 1 at 1 A g − 1 with good capacitance retention capability and good cycling stability, and outputs a high average energy power density of 10.8 W h kg − 1 and a high maximum power density of 595 kW kg − 1 in aqueous KOH electrolyte. Due to the great pseudocapacitance in aqueous H 2 SO 4 electrolyte, the specific capacitance of the 3DNGN can reach a high value of 345 F g − 1 at 1 A g − 1 .

To explore the influence of molecular structure on formation excimer and obtain high efficiency white polymer light-emitting devices (WPLEDs), two novel blue-emitting dinuclear cyclometalated iridium (III) complexes, namely C 8 DBCzC 6 -DF 2 Ir(pic) and DPy(TPA)-C 6 DBCzC 6 -DF 2 Ir(pic), have been successfully synthesized and characterized, in which DBCz is 3,6-diphenyl-carbazole bridged core, DPy(TPA) is 4,4′-di(pyren-1-yl)triphenylamine deep blue-emitting fluorescent chromophore, DF 2 Ir(pic) is dinuclear iridium (III) bis[(4,6-difluorophenyl)-pyridinato-N,C 2′ ](picolinate) blue-emitting phosphorescent chromophore, and C 6 is an nonconjugated dioxyhexyloxy linkage, respectively, and each parts of molecular skeleton are wired through nonconjugated ether linkage. Their thermal, electrochemical and optophysical properties were primarily investigated. Near white light emission were obtained in the C 8 DBCzC 6 -DF 2 Ir(pic)-doped devices using a blend of polyvinylcarbazole (PVK) and 2-(4-biphenyl)-5-(4- tert -butylphenyl)-1,3,4-oxadiazole (PBD) as a host matrix at dopant concentrations of 1 wt%. However, after triphenylamine functionalized pyrene DPy(TPA) replaced the alkyl chain C 6 unit, at first unexpected, substitution effect occurs, more stable white light emissions with the CIE coordinates of (0.297 ± 0.009, 0.345 ± 0.007) and a maximum brightness of 961 cd/m 2 were observed in the same device at the doping concentrations of 8 wt% under different applied voltages from 8 to 13 V. The results indicate that aggregation/excimer emissions of iridium (III) complexes can be effectively tuned by inserting a deep blue fluorescent chromophore into the dual picolinic acid derivative, and it aslo be an efficient way to get white-emitting WPLEDs.

This paper reports an 840 GHz monolithic frequency tripler based on 25-μm GaAs membrane and planar Schottky diode. An improved balanced structure is proposed and used in the circuit, which can provide an excellently balanced RF path. An electromagnetic model of planar Schottky diodes is established based on physical characteristics for accurate simulation of frequency tripler. At a 10 dB m input power, the improved structure increases the conversion efficiency from 3.57% to 5.82%, and enhances the output power from -4.47 dB m to -2.35 dB m. Among the frequency range of 839 GHz to 849 GHz, the conversion efficiency is typically greater than 3%.

The lack of electron acceptors with suitable green solvent processing and excellent device performance is an important problem that hinders the development and commercialization of organic solar cells (OSCs). Here, an ortho-ortho perylene diimide (PDI) dimer (oo-2PDI) is developed and used as an acceptor for use in efficient green-solvent-processed (GSP) OSCs. By using chlorobenzene (CB), anisole, and ortho-xylene as the processing solvents, power conversion efficiencies (PCEs) of 5.04%, 5.03%, and 5.78% were achieved without the additive, respectively. In addition, the non-fullerene oo-2PDI-based GSPOSCs show superior photovoltaic performance to [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)-based GSPOSCs under identical conditions. Therefore, these results demonstrate the possibility of achieving efficient non-fullerene GSPOSCs.

Gut microbiota of aquatic animals have a crucial impact on several host physiological processes and some of commensal bacteria may have the potential to be used as probiotics. The aim of the present study was to investigate the effects of hybrid sturgeon (Acipenserbaerii x Acipenserschrenckii) gut microbiota induced by growth worry free (GWF®) on the growth, immune regulation and disease resistance in sturgeon using a germ free (GF) zebrafish model. Sturgeons were fed for three weeks with GWF® supplemented or basal diet. At the end of the experiment gut microbiota of sturgeon, fed on either experimental diet were transferred to GF zebrafish for three days. Then the expression of growth promotion, inflammation and non-specific immune related genes were assessed. Moreover, zebrafish colonized with either the experimental microbiota were challenged with Aeromonas veronii Hm091 for two days. Results indicated that the expression of growth promotion related genes (mTOR, MYoD, Myogenin) and non-specific immune related genes (DEFBL-1, lysozyme, C3a, and anti-inflammatory gene TGF-β), was significantly up-regulated in GF zebrafish colonized with microbiota from GWF® sturgeon (P

Pseudomonas protegens CHA0 is a well-characterized plant-growth promoting rhizobacterium commonly used as biofertilizer or biocontrol agent for plant growth promotion and disease control. Genetically engineered strain CHA0-ΔretS-nif with introduced nitrogen-fixing ability and enhanced bactericidal activity has the potential to stimulate plant growth and suppress phytopathogens. Field experiments was conducted to evaluate the effects of CHA0-ΔretS-nif inoculation on garlic growth, disease prevention and soil microbial diversity. Results revealed that CHA0-ΔretS-nif inoculation largely promoted garlic growth and yields. The total production of garlic in the CHA0-ΔretS-nif treated fields reached up to 34.25 T/ha, with an increase of 12.03% when compared to the untreated control (30.58 T/ha). When nitrogen application was reduced by 25%, CHA0-ΔretS-nif inoculation had a similar beneficial effects on garlic production with an increase of 10.62% than the uninoculated control. Moreover, CHA0-ΔretS-nif inoculation increased the bacterial population in the garlic rhizosphere and had significant effects against garlic root rot. Disease index in the CHA0-ΔretS-nif inoculated treatment (2.65%) was lower than the uninoculated control (3.31%). These results indicate that P. protegens CHA0-ΔretS-nif inoculation can help reduce chemical fertilizers and pesticides usage, and may be considered as an eco-friendly, viable alternative technology to increase food production in the future.

Two kinds of fluorescent sensors (G1 and G2) for Fe3+ bearing 1H-imidazo [4,5-b] phenazine derivatives have been designed and synthesized. G1 can display ON-OFF-type fluorescence charged with high selectivity and sensitivity toward Fe3+ in DMSO solutions. And other cations, including Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Zn2+, Cr3+, and Mg2+ had no influence on the probing behavior. The detection limit of the sensor G1 towards Fe3+ is 2.860 × 10−7 M. Once combined with Fe3+, G1 displayed high specificity for H2PO4−. Furthermore, in the situ generated G1–Fe3+ ensemble could recover the enhanced fluorescence upon the addition of H2PO4− resulting in an ON-OFF-ON sensing with a detection limit of 1.866 × 10−7 M in the same medium. Notably, this sensor serves as a recyclable component in sensing materials. The reversibility and selectivity of G1/G1 + Fe3+ toward Fe3+/H2PO4− ions as a sequence dependent molecular keypad lock using the G1, Fe3+ and H2PO4− as three different chemical inputs. In addition, the test strip based on G1 was fabricated, which could act as a convenient and efficient Fe3+ test kit.

Three novel linear-shape small molecules of TPA(DPP-PN)(2), Cz(DPP-PN)(2) and Fl(DPP-PN)(2) were synthesized and characterized, which contain the same arm of diketopyrrolopyrrole (DPP) and large aryl terminals of phenanthrene (PN), as well as different aryl centers of triphenylamine( TPA), carbazole (Cz) and fluorene (Fl), respectively. Narrower optical band gaps (1.62-1.69 eV) and lower highest occupied molecular orbital energy levels (-5.71 to -5.79 eV) were observed in these small molecules compared with those corresponding values of the analogues without the PN terminal. Furthermore, the Cz(DPP-PN)(2) and Fl(DPP-PN)(2) molecules with planar centers exhibited better photovoltaic performance than the TPA(DPP-PN)(2) with a non-planar center in the solution-processed organic solar cells using [6,6]-phenyl-C61-butyric acid methyl ester as acceptor. The highest power conversion efficiency of 4.13% and a short-circuit current density of 8.77 mA cm(-2) were obtained in the Fl(DPP-PN)(2) based cell. It indicates that introducing large planar aryl groups as molecular center and terminals is an efficient strategy to improve absorption and photovoltaic performances in their linear-shape A-D-A-type small molecules. (C) 2014 Elsevier B.V. All rights reserved.

A chemosensor (CS) was designed and synthesized by simple method. Dual-channel instant detection of CN− was achieved under acidic conditions. It showed an immediate visible color change from yellow to colorless and blue fluorescence appearance when CN− was added. Colorimetric and fluorometric methods showed the detection limits of CN− were 3.9×10−8 and 3.1×10−9 M, respectively. The mechanism of chemosensor reactions with CN− ion was examined using 1H NMR spectroscopy, FTIR spectroscopy, and DFT calculations. Test strips, which served as convenient and efficient CN− test kits, were fabricated based on the sensor.

Two novel D-A-Ar-type small molecules of TPA-DPP-P and TPA(DPP-P)(2) were synthesized and characterized, in which triphenylamine (TPA), diketopyrrolopyrrole (DPP) and phenanthrene (P) were used as the donor (D) core, acceptor (A) arm, and enlarged pi-system of polycyclic arene (Ar) terminal. Their absorptive, electro-chemical, thermal, and photovoltaic properties were preliminary investigated. Significantly improved photo-physical and photovoltaic performances were observed for both small molecules containing the planar P terminal in comparison with those for their parent D-A-type molecule of TPA-DPP. The highest power conversion efficiency (PCE) of 3.42% and a maximum short-circuit current density (J(sc)) of 9.2 mA/cm(2) were obtained in the solution-processed TPA(DPP-P)(2)-based solar cells using [6,6]-phenyl-C-71-butyric acid methyl ester (PC71BM) as acceptor. The PCE and Jsc values are 8.76 and 4.97 times higher than those of the TPA-DPP-based cells, respectively. It indicates that appending the enlarged p-system of the planar P terminal and incorporating the DPP-P arm into D-A-type small molecule are efficient approaches to improve photo-physical and photovoltaic performances for its resulting molecules. (C) 2014 Elsevier B. V. All rights reserved.

A long wavelength emission fluorescent (600 nm) and colorimetric (from pink to yellow) chemosensor with high selectivity for H2PO4− ions was designed and synthesized according to the twisted intramolecular charge transfer (TICT) mechanism. The sensor was bearing a 2-pyridine-1H-imidazo[4,5-b]phenazine and Zn2+ metal complex (S2–Zn), which shown brilliant fluorescent and colorimetric response for H2PO4− anions in aqueous solution. The detection limit of the sensor toward H2PO4− is 2.4 × 10−6 M, and other anions, including F−, Cl−, Br−, I−, AcO−, HSO4−, ClO4− and CN− had nearly no influence on the probing behavior. The test strips based on 2-pyridine-1H-imidazo[4,5-b]phenazine and Zn2+ metal complex (S2–Zn) were fabricated, which could act as a convenient and efficient H2PO4− test kits.