Search

Objective To explore the value of serum aquaporin 8 (AQP8) expression in evaluating the degree of hydrolabyrinth and predicting prognosis in patients with Meniere’s disease. Methods 105 patients with Meniere’s disease in our hospital were included in the Meniere’s disease group.Another 102 healthy subjects in our hospital were included as the control group. The multivariate Logistic regression was used to analyze the influencing factors of poor prognosis in patients with Meniere’s disease. Results The expression of serum AQP8 mRNA in the Meniere’s disease group was greatly higher than that in the control group (P

Swine-origin H1N1 influenza virus caused an outbreak in human in 2009 (H1N1/pdm09). We isolated several novel reassortant influenza A viruses bearing the H1N1/pdm09 segments (PB2, PB1, PA and NP) from dogs, which showed high similarity with H1N1 swine influenza virus in the previous study. To understand the molecular basis of swine-origin H1N1 reassortant canine influenza virus adaptation to new host species, the mouse-adapted variants of H1N1 canine virus were obtained by serial lung-to-lung passages in BALB/c mice. After thirteen passages, the virus significantly enhanced replication in MDCK cells and became lethal to mice. Six adaptive mutations mapped to two in the ribonucleoprotein (RNP) complex (PB2-E578D, PA-T97I), two in hemagglutinin (HA-N198D and A227E), two in the non-structural protein 1 and nuclear export protein (NS1-A53D and NEP-R42K), indicating that they may contribute to the increased virulence and replication. The results provided valuable insights into how the swine-origin influenza virus adapt to a new host that deserves more attentions.

H1N1 reassortants between the swine Eurasian avian-like (EA) and H1N1 2009 pandemic (H1N1 pdm/09) viruses have been circulating stably in pig populations for more than ten years, and they may have contributed to increased human infections. Whether these H1N1 viruses acquire adaptive mutations to increase their pathogenicity towards a new host is unknown. To address this problem, mouse-adapted (MA) variants of swine-origin EA H1N1 influenza virus isolated from dogs (A/canine/Guangxi/LZ57/2015[LZ57-MA]) were generated by serial lung-to-lung passages in BALB/c mice. These exhibited greater virulence and replication capability than the wild-type virus (LZ57-WT). Of the six adaptive mutations, two were mapped to the ribonucleoprotein (RNP) complex (PB2-E578D and PA-T97I), two to hemagglutinin (HA-N198D and HA-A227E) and two to the non-structural protein 1 (NS1) and nuclear export protein (NS1-A53D and NEP-R42K, respectively). Reverse genetic substitution of the viral genes and mutation experiments demonstrated that the mutations in PA-T97I could enhance the polymerase activity, but a significant downregulation of activity was seen with PB2-E578D, which was consistent with a decrease in virulence. However, HA and NS, which are genes that act synergistically, were found to be determinants of virulence in mice. The reassortant viruses bearing HA mutations (N198D and A227E) were acquired during adaptation enhanced early-stage viral replication in mammalian cells. The single-point mutations in the NS genes had limited effects on virulence. Furthermore, a combination of HA (N198D and A227E) with NS(A53D) in the rLZ57-WT backbone resulted in efficient replication and a significant increase in virulence. The results suggest that these substitutions could compensate for the polymerase function and contribute to enhanced virulence, which highlights a major role for mutations in the HA and NS genes.

Host switch events of influenza A viruses (IAVs) continuously pose a zoonotic threat to humans. In 2013, swine-origin H1N1 IAVs emerged in dogs soon after they were detected in swine in the Guangxi province of China. This host switch was followed by multiple reassortment events between these H1N1 and previously circulating H3N2 canine IAVs (IAVs-C) in dogs. To evaluate the phenotype of these newly identified viruses, we characterized three swine-origin H1N1 IAVs-C and one reassortant H1N1 IAV-C. We found that H1N1 IAVs-C predominantly bound to human-type receptors, efficiently transmitted via direct contact in guinea pigs and replicated in human lung cells. Moreover, the swine-origin H1N1 IAVs-C were lethal in mice and were transmissible by respiratory droplets in guinea pigs. Importantly, sporadic human infections with these viruses have been detected, and preexisting immunity in humans might not be sufficient to prevent infections with these new viruses. Our results show the potential of H1N1 IAVs-C to infect and transmit in humans, suggesting that these viruses should be closely monitored in the future.

The layered oxyselenides with the formula LnCrSe2O (Ln = Ce-Nd) were synthesized via molten salt methods. The isostructural compounds crystallize in the monoclinic space group of C2/m. The crystal structures feature ∞2[CrSe2O]3- motifs stacked along the a axis, which are separated by Ln3+ ions. The ∞2[CrSe2O]3- layers are composed of [Cr1Se6]9- and [Cr2Se4O2]9- octahedra via corner and edge sharing. Powder X-ray diffraction results confirm the phase purities of the as-synthesized compounds. LnCrSe2O (Ln = Ce-Nd) show typical antiferromagnetic ordering with TN = 125, 120, and 118 K, respectively. Heat capacity measurement for NdCrSe2O indicates that the Debye temperature is 278.4 K. Similar metal-to-semiconductor phase transitions were observed for LnCrSe2O (Ln = Ce-Nd) plates with transition temperatures of 115, 109, and 95 K, respectively. NdCrSe2O also possesses a magnetoresistance effect at low temperature (

Multiband materials have received increasing attention due to their superior solar absorption properties. Here we design a new multiband compound, namely Ba5Bi2Co2S10, which crystallizes in the space group C22h-P21/m (No. 11) of the monoclinic system. Ba5Bi2Co2S10 is composed of one-dimensional 1∞[Bi2Co2S10]10- chains along the a axis. The adjacent chains are separated by Ba2+ ions. The optical band gap of the compound is 1.05 eV and 0.74 eV, presenting typical multi-absorption characteristics. First-principles calculations, which are perfectly consistent with the experimental results, show that the hybrid coupling effect between Co and S gives rise to multiband characteristics. Evident optoelectronic conversion properties were observed under visible light illumination with a photocurrent density of 4.0 mA cm-2 at 1 V.

Ilamycins are cyclopeptides with novel structures that have been isolated from different Actinomycetes. They showed strong anti-tuberculosis activity and could serve as important anti-tuberculosis drug leads. The functions of the pre-tailoring and the post-tailoring genes in the biosynthesis of ilamycins have been elucidated, but the functions of the regulatory and transporter genes remain elusive. We reported herein the functions of four genes in ilamycin biosynthetic gene cluster (ila BGC) including two regulatory genes (ilaA and ilaB) and two transporter genes (ilaJ and ilaK) and the heterologous expression of ila BGC. The IlaA and IlaB were unambiguously shown to be negative and positive regulator of ilamycins biosynthesis, respectively. Consistent with these roles, inactivation of ilaA and ilaB (independent of each other) was shown to enhance and abolish the production of ilamycins, respectively. Total yields of ilamycins were enhanced 3.0-fold and 1.9-fold by inactivation of ilaA and overexpression of ilaB compared to those of in the Streptomyces atratus SCSIO ZH16, respectively. In addition, the ila BGC was successfully expressed in Streptomyces coelicolor M1152, which indicated that all biosynthetic elements for the construction of ilamycins were included in the PAC7A6. These results not only lay a foundation for further exploration of ilamycins, but also provide the genetic elements for synthetic biology.

Drifting snow is a significant factor in snow redistribution and cascading snow incidents. However, field observations of drifting snow are relatively difficult due to limitations in observation technology, and drifting snow observation data are scarce. The FlowCapt sensor is a relatively stable sensor that has been widely used in recent years to obtain drifting snow observations. This study presents the results from two FlowCapt sensors that were employed to obtain field observations of drifting snow during the 2017–2018 snow season in the southern Altai Mountains, Central Asia, where the snow cover is widely distributed. The results demonstrate that the FlowCapt sensor can successfully acquire stable field observations of drifting snow. Drifting snow occurs mainly within the height range of 80-cm zone above the snow surface, which accounts for 97.73% of the total snow mass transport. There were three typical snowdrift events during the 2017–2018 observation period, and the total snowdrift flux caused during these key events accounted for 87.5% of the total snow mass transport. Wind speed controls the occurrence of drifting snow, and the threshold wind speed (friction velocity) for drifting snow is approximately 3.0 m/s (0.15 m/s); the potential for drifting snow increases rapidly above 3.0 m/s, with drifting snow essentially being inevitable for wind speeds above 7.0 m/s. Similarly, the snowdrift flux is also controlled by wind speed. The observed maximum snowdrift flux reaches 192.00 g/(m2·s) and the total snow transport is 584.9 kg/m during the snow season. Although drifting snow will lead to a redistribution of the snow mass, any accumulation or loss of the snow mass is also affected synergistically by other factors, such as topography and snow properties. This study provides a paradigm for establishing a field observation network for drifting snow monitoring in the southern Altai Mountains and bridges the gaps toward elucidating the mechanisms of drifting snow in the Altai Mountains of Central Asia. A broader network of drifting snow observations will provide key data for the prevention and control of drifting snow incidents, such as the design height of windbreak fences installed on both sides of highways.

The organic-inorganic lead halide perovskites are attractive materials for photovoltaic application. The most widely studied perovskites based on methyl ammonium organic cation are less likely to form an ideal high-symmetry configuration at room temperature, leading to the appearance of local lattice strain. Herein, this study reports a strategy for the construction of thermally stable cubic perovskites at room temperature through the incorporation of the larger organic cation dimethyl ammonium. Detailed characterization on the single crystals and thin films reveals the formation of cubic phase with the addition of a certain amount of dimethyl ammonium at room temperature. With the presence of dimethyl ammonium, the nonradiative recombination in perovskite is suppressed, showing a longer PL lifetime and hole diffusion length. The more efficient charge extraction leads to an improvement in the photocurrent density, and then the device efficiency from 17.1% to 18.6%, together with an enhanced thermal stability at 85 °C. The influence of incorporating a larger organic cation on the structural configuration, optical properties, charge extraction, as well as the photovoltaic performance is systematically investigated, which offers an alternative way to improve the intrinsic stability of hybrid perovskites.

We report two new chromium chalcogenides Cr(en)(3)SbSe4 and Cr(en)(2)AsSe3 which were obtained by solvothermal reactions at 170 degrees C. Cr(en)(3)SbSe4 adopts the tetragonal space group P4(2)bc with isolated [Cr(en)(3)](3+) ions and [SbSe4](3-) tetrahedrons. Cr(en)(2)AsSe3 is a molecular crystal with the monoclinic space group P2(1)/n. It has [Cr(en)(2)Se-2](-) octahedrons and [AsSe3](3-) triangle cones which are edge shared by Se atoms. Cr(en)(3)SbSe4 has a band gap of 2.3 eV, whereas Cr(en)(2)AsSe3 displays multiple-absorption characters with two absorption edges at 1.7 and 2.2 eV, respectively. Remarkably, Cr(en)(3)SbSe4 is a Curie-Weiss paramagnet between 2 and 300 K with an effective magnetic moment of 3.98 mu B, and is a potential magneto-caloric material with -Delta S-m = 16.3 J (kg K)(-1) at 4 K and Delta H = 8 T. Cr(en)(2)AsSe3 shows antiferromagnetism below 9 K. (c) 2018 Published by Elsevier B.V.

A new chalcogenide Na2ZnSnS4 has been successfully synthesized by using Na2S2 as reactive flux. Na2ZnSnS4 crystallizes in the tetragonal system with space group of I4. Its cell parameters are a = 6.4835(6) A and c = 9.134(1) A. The structure is a derivative of AgGaS2, in which the Ag+ ions are replaced by Na+ ions and the Ga3+ ions are replaced by Zn2+ and Sn4+ ions. All three cations are in seriously distorted tetrahedral geometry with a distortion factor (η = c/ a) of 1.4. Optical measurements show that the Na2ZnSnS4 powder sample has a large transparent range from 0.8 to 25 μm and a wide band gap of 3.1 eV. It exhibits large second-harmonic generation intensity of 0.9 × AgGaS2 in the grain size range from 41 to 74 μm. First-principles calculation results reveal that the valence band maximum and conduction band minimum are mainly composed of S 3p, Zn 3d orbitals and Sn 5s, S 3p orbitals, respectively.

Considered a “mixing vessel” for influenza viruses, pigs can give rise to new influenza virus reassortants that can threaten humans. During our surveillance of pigs in Guangxi, China from 2013 to 2015, we isolated 11 H1N1 and three H3N2 influenza A viruses of swine origin (IAVs-S). Out of the 14, we detected ten novel triple-reassortant viruses, which contained surface genes (hemagglutinin and neuraminidase) from Eurasian avian-like (EA) H1N1 or seasonal human-like H3N2, matrix (M) genes from H1N1/2009 pandemic or EA H1N1, nonstructural (NS) genes from classical swine, and the remaining genes from H1N1/2009 pandemic. Mouse studies indicate that these IAVs-S replicate efficiently without prior adaptation, with some isolates demonstrating lethality. Notably, the reassortant EA H1N1 viruses with EA-like M gene have been reported in human infections. Further investigations will help to assess the potential risk of these novel triple-reassortant viruses to humans.

Two new layered sulfides, namely NaMn0.5Sn0.5S2 and NaFe0.5Sn0.5S2, have been successfully synthesized. Their structures were determined using single crystal X-ray diffraction. The two compounds crystallize in trigonal system with space group R 3 ¯ m. Their cell parameters are a = 3.7630 (5) A, c = 19.896 (3) A and a = 3.711(5) A, c = 20.00(3) A for NaMn0.5Sn0.5S2 and NaFe0.5Sn0.5S2, respectively. Light absorption measurements showed that band gap of NaMn0.5Sn0.5S2 and NaFe0.5Sn0.5S2 are 1.5 eV and 0.7 eV, respectively. Magnetization measurements showed that NaMn0.5Sn0.5S2 compound is paramagnetic from 2 K to 300 K with an effective moment of 6.4 μB per Mn2+ and a Weiss temperature Θp of −71 K NaFe0.5Sn0.5S2 undergoes an antiferromagnetic transition at TN = 14 K, with an effective moment of 4.5 μB per Fe2+ and a Weiss temperature Θp of −60 K. Heat capacity measurements showed that NaMn0.5Sn0.5S2 has a Debye temperature of 407.4 K and short range ordering at low temperature. The current density of NaFe0.5Sn0.5S2 increased from 0.2 mA⋅cm−2 to 0.3 mA cm−2 under illumination at a voltage bias of 5 V, indicating that it is a good photoelectric material.

Extensively investigated BiVO4 photoanode for solar water splitting suffers from low product of light absorption and charge separation efficiency (ηabs × ηsep) due to the lack of high surface area supporting materials as a charge collector. Such a host|guest heterostructure is not only effective but also attractive, but it is too complicated to understand the original process of ηsep. Here, a host–guest heterostructure of Nb-doped TiO2 nanowires supporting BiVO4 nanoparticles is fabricated to investigate its visible-light charge injection efficiency (ηinj) and charge collection efficiency (ηcol). With the aid of gradient W doping in BiVO4 guest, the Nb-doped TiO2|gradient W-doped BiVO4 (N:T|g-W:B) produces ηinj = 82% and ηcol = 95% to yield a very high value for ηabs × ηsep of 55.3% at 0.6 VRHE, which is one of the highest values among these nanostructure-host|BiVO4-geust photoanodes. By being further coated with Co–Pi, the photoanode simultaneously achieves a high value of ηtrans for efficient solar wate...

Six isostructural antiperovskite-derived chalcohalides, Ba2MQ3X (M = As, Sb; Q = S, Se; X = Cl, Br, I), crystallizing in the space group Pnma, have been synthesized by solid-state reactions. The crystal structure features a 3D framework with the [XBa5]9+ disordered square pyramids as building blocks and [MQ3]3- units filling the interspace. [XBa5]9+ disordered square pyramids are edge-sharing along [010], derived from the fusing of the two pyramids in octahedral [XBa6]11+. Surprisingly, Ba2AsS3X (X = Cl, Br, I) show almost the same optical band gap of 2.80 eV, and Ba2AsSe3X (X = Br, I) also have a similar band gap of 2.28 eV. The optical band gap of Ba2SbS3I is 2.64 eV. First-principles calculations reveal that the optical absorption is attributed to the transitions between Q np at the valence band maximum (VBM) and M np-Q np at the conduction band minimum (CBM). These compounds also possess interesting photoluminescence properties with splitting emission peaks on excitation at 200 nm.

With changing climatic conditions and snow cover regime, regional hydrological cycle for a snowy basin will change and further available surface water resources will be redistributed. Assessing snow meltwater effect on runoff is the key to water safety, under climate warming and fast social-economic developing status. In this study, stable isotopic technology was utilized to analyze the snow meltwater effect on regional hydrological processes, and to declare the response of snow hydrology to climate change and snow cover regime, together with longterm meteorological and hydrological observations, in the headwater of Irtysh River, Chinese Altai Mountains during 1961-2015. The average δ18O values of rainfall, snowfall, meltwater, groundwater and river water for 2014–2015 hydrological year were -10.9‰, -22.3‰, -21.7‰, -15.7‰ and -16.0‰, respectively. The results from stable isotopes, snow melting observation and remote sensing indicated that the meltwater effect on hydrological processes in Kayiertesi River Basin mainly occurred during snowmelt supplying period from April to June. The contribution of meltwater to runoff reached 58.1% during this period, but rainfall, meltwater and groundwater supplied 49.1%, 36.9% and 14.0% of water resource to annual runoff, respectively. With rising air temperature and increasing snowfall in cold season, the snow water equivalent (SWE) had an increasing trend but the snow cover duration declined by about one month including 13-day delay of the first day and 17-day advancement of the end day during 1961–2016. Increase in SWE provided more available water resource. However, variations in snow cover timing had resulted in redistribution of surface water resource, represented by an increase of discharge percentage in April and May, and a decline in June and July. This trend of snow hydrology will render a deficit of water resource in June and July when the water resource demand is high for agricultural irrigation and industrial manufacture.

A putative toxin gene of cry50Ba was successfully expressed in E. coli cells and confirmed that the purified Cry50Ba toxin had very high toxic activity against Culex quinquefasciatus larvae. Furthermore, the potential synergism of Cry50Ba toxin with Cry2Aa, Cry4Aa and Cry11Aa at a ratio of 1:1 was investigated. Although no significant synergism with other toxins was observed, the Cry50Ba as a novel toxin could be used to delay rapid onset of resistance in mosquito.

A new compound K 2 Cu 2 GeS 4 was successfully synthesized by using molten thiourea reactive flux method. The structure was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system of space group P 2/ c with a unit cell of a = 7.063 (3) A, b = 5.435 (3) A, c = 11.037 (6) A and β = 112.83 (3)°. The crystal structure of K 2 Cu 2 GeS 4 is composed of defective anti -PbO like [Cu 2 GeS 4 ] 2− layers which are interleaved by K + cations. This compound is a semiconductor with an indirect band gap of 2.3 (1) eV, which is derived from optical absorption spectrum. First principles calculations reveal that K 2 Cu 2 GeS 4 has interesting intermediate bands consisting of Ge-4 s and S-3 p orbitals. This new semiconductor is potentially suitable for solar photocatalytic and photoelectric applications.

Selenium doped NaCl-type superconductor SnAs1−xSex (x=0–0.13) were made through solid state reaction. EDS results show that Se content increases with Se doping until over doped in SnAs0.9Se0.1 and SnAs0.87Se0.13 (around 2.7%). PXRD patterns confirmed the main phase of the six doped samples are SnAs. The cell parameters of doped SnAs were calculated using Rietveld refinements. Their cell parameters increase almost linearly with x until x reaches 13%. Single crystal diffraction measurement results show that there are no interstitial atom in doped SnAs. We conclude that Se atoms are substitutional atoms in SnAs. The superconducting onset temperatures (Tc onset, under a magnetic field of 10 Oe) of SnAs increased from 3.8 K to 4.5 K by 10% Se doping. ρ-T curves of 1%, 5% and 10% Se doped samples show that all the three samples are metallic. Upper critical field Hc2(0) of 1%, 5% and 10% Se doped samples are 294 Oe, 649 Oe and 1011 Oe, respectively.

The mixed-metal sulfide compound with the formula Ba2Fe0.6V1.4S6 was successfully synthesized via solid-state reaction. Ba2Fe0.6V1.4S6 has a quasi-one-dimensional structure and crystallizes in the hexagonal space group P63/mmc. The structure is composed of face-sharing anion octahedron [MS6]8– (M = V or Fe) units to construct infinite chains along the c axis, in which the Fe atoms randomly occupy the V sites. The Ba2+ ions reside between adjacent chains. Magnetic susceptibility measurements reveal a transition between paramagnetism and ferromagnetism around 25 K. The small polaron hopping (SPH) conduction behavior has been observed in the higher temperature region (75–300 K), while in the lower temperature region (25–74 K), the resistivity features a variable range hopping mechanism (VRH). The analysis of density of states indicates that Fe-3dz2 and S-3p states mainly dominate the valence band maximum, while Fe-3dz2 states contribute significantly to the magnetic susceptibility.

One-dimensional TiO2 nanowire is the top-performing semiconductor among photoanodes for photoelectrochemical water splitting, but still limited to a fraction of the theoretically photocurrent because of modest charge transport and low charge separation properties. Here, we demonstrate high-crystallized nanowires of Nb-doped rutile TiO2 for significantly increasing electron carrier density through a convenient method. The optimized Nb-doped TiO2 nanowires (0.5 mol% in the Nb/Ti ratio) yield a high value of charge separation efficiency (ηsep) of 97.39% at 1.23 VRHE, which is about 3 times as much as that of pristine sample (33.61% at 1.23 VRHE). Moreover, the photoanode of Nb-doped TiO2 nanowires can achieve high charge transfer efficiency (ηtrans) (91.07% at 1.23 VRHE) without any oxygen evolution reaction catalysts. These results indicate that through appropriate amount of Nb doping can move the performance of TiO2 nanowires to their theoretical potential.

Oxygen stoichiometry is critical for physical properties, but it is hard to precisely control in many multivalent transition metal oxides, for example, cuprate superconductors, magnetoresistive manganite oxides, and TiOx (x < 2). We have developed a new method to synthesize rock-salt TiO in a sealed and evacuated quartz tube by using KClO4 as the only oxygen source to react with elemental Ti (in a Ti/O molar ratio of 1:1). The stoichiometric titanium monoxide (TiO) exhibits an enhanced superconductivity transition temperature (Tc) of 5.5 K, which is superior to the reported results of 0.5–2.3 K. The new synthetic method provides an excellent way to prepare stoichiometric oxides, and the enhanced superconductivity of TiO may initialize the restudy of the transport properties of Ti-containing oxides.

The challenge of light-driven controlled radical polymerization through non-noble metal catalyst remains the most significant issue. Ferrocene-bearing microporous aromatic polymer nanosheets (termed “FeMAP-11”) that feature high chemical stability were reported here to synergistically combine the advantageous properties of the redox-active ferrocene units and the conjugated microporous polymers (CMPs), and to be able to serve as photocatalyst for activators regenerated by electron transfer atom transfer radical polymerization (AGET-ATRP). It succeeded in initiating polymerizations of 3 common vinyl monomers, i.e. methyl methacrylate (MMA), methacrylate (MA) and styrene (St), and produced polymers with controlled molecular weight and relatively low molecular weight dispersity (˜1.3). Benefiting from steric hindrance through ketone-amine chemistry, the microporous catalyst with tolerance to acidic and basic media was found stable under the AGET-ATRP conditions. It showed negligible metal leaching and good recyclability for at least 10 cycles without sacrifice of its catalytic performance. Our tests proved that FeMAP-11 exceeded the state-of-the-art ATRP photocatalysts such as UiO-66-NH2, titanium MOF-901 and the commercial P-25 Titania, demonstrating promising potential in catalysis in view of green chemistry.

Marine Streptomyces sp. are an important source of bioactive compounds owing to their unique habitats and metabolic pathways. Whole-genome sequencing and bioinformatics analyses have shown that the potential of synthesizing secondary metabolites from marine-derived Streptomyces has been substantially underestimated. Genome mining is an integrated strategy used to discover natural products based on gene cluster sequences and biosynthetic pathways. Its emergence has greatly enhanced the discovery of natural compounds from marine Streptomyces, thereby yielding a large number of bioactive molecules with novel structures and potent activities. In this review, we briefly summarize the current applications of genome mining in marine Streptomyces, such as bioinformatics-based optimization of culture conditions, ribosome engineering, control of regulatory networks, heterologous expression of biosynthetic gene cluster, and combinatorial biosynthesis of natural compounds. Furthermore, we discuss the factors hindering the utilization of marine-derived natural products and conclude with the prospects for this technique.

The layered oxyselenides with the formula

Multiband materials have received increasing attention due to their superior solar absorption properties. Here we design a new multiband compound, namely Ba5Bi2Co2S10, which crystallizes in the space group C22h-P21/m (No. 11) of the monoclinic system. Ba5Bi2Co2S10 is composed of one-dimensional 1∞[Bi2Co2S10]10- chains along the a axis. The adjacent chains are separated by Ba2+ ions. The optical band gap of the compound is 1.05 eV and 0.74 eV, presenting typical multi-absorption characteristics. First-principles calculations, which are perfectly consistent with the experimental results, show that the hybrid coupling effect between Co and S gives rise to multiband characteristics. Evident optoelectronic conversion properties were observed under visible light illumination with a photocurrent density of 4.0 mA cm-2 at 1 V.

Ion doping is an effective approach to improve the properties of hybrid perovskite CH 3 NH 3 PbI 3 , such as chemical stability and solar absorption. Here Bi 3+ -doped CH 3 NH 3 PbI 3 was synthesized via cooling crystallization process in aqueous solution. Along with the Bi 3+ doping, the bandgap of CH 3 NH 3 PbI 3 could be significantly narrowed, by the maximum value of 140 meV at the optimal doping level of 1.6 M %. Transient photovoltage measurement (TPV) revealed the Bi 3+ -doped CH 3 NH 3 PbI 3 could achieve a charge carrier lifetime of 280 μs, which was almost twice longer than that of pristine CH 3 NH 3 PbI 3 (157 μs). The prolonged carrier lifetime of Bi 3+ -doped CH 3 NH 3 PbI 3 was supposed to be attributed to its lower packing factor (PF), which was caused by the CH 3 NH 3 + vacancy (V MA ) after doping This work provides a new approach to tune the band gap and charge carrier lifetime of the hybrid perovskite CH 3 NH 3 PbI 3 , which should be promising to further improve the performance of perovskite-based photovoltaic devices.

Black TiO2 with various nanostructures and phase constitutions have been reported to exhibit excellent photocatalytic and photoelectrochemical (PEC) performance. Here, we report the fabrication of black nanostructured TiO2 B through hydrogen plasma assisted reduction and its enhanced PEC properties for the first time. Both the obtained TiO2 B and black TiO2 B are single crystalline nanowires, while the black TiO2 B samples exhibit much stronger visible and infrared light absorption. The optimal black TiO2 B sample obtained by hydrogen plasma treatment at 425 °C yields a photocurrent density of 0.85 mA cm−2, a rather low onset potential of −0.937 VAg/AgCl and a high applied bias photon-to-current efficiency (ABPE) of 0.363%, which is far superior to the TiO2 B (0.15 mA cm−2 photocurrent, −0.917 VAg/AgCl onset potential and 0.138% ABPE). The significantly enhanced PEC performance of the black TiO2 B is ascribed to the introduction of moderate surface oxygen vacancies. These results indicate that the black TiO2 B is a promising material for PEC application and solar energy utilization.

The advent of microporous organic polymers (MOPs) has delivered great potential in gas storage and separation (CCS). However, the presence of only micropores in these polymers often imposes diffusion limitations, which has resulted in the low utilization of MOPs in CCS. Herein, facile chemical activation of the single microporous organic polymers (MOPs) resulted in a series of hierarchically porous carbons with hierarchically meso-microporous structures and high CO2 uptake capacities at low pressures. The MOPs precursors (termed as MOP-7-10) with a simple narrow micropore structure obtained in this work possess moderate apparent BET surface areas ranging from 479 to 819 m(2) g(-1). By comparing different activating agents for the carbonization of these MOPs matrials, we found the optimized carbon matrials MOPs-C activated by KOH show unique hierarchically porous structures with a significant expansion of dominant pore size from micropores to mesopores, whereas their microporosity is also significantly improved, which was evidenced by a significant increase in the micropore volume (from 0.27 to 0.68 cm(3) g(-1)). This maybe related to the collapse and the structural rearrangement of the polymer farmeworks resulted from the activation of the activating agent KOH at high temperature. The as-made hierarchically porous carbons MOPs-C show an obvious increase in the BET surface area (from 819 to 1824 m(2) g(-1)). And the unique hierarchically porous structures of MOPs-C significantly contributed to the enhancement of the CO2 capture capacities, which are up to 214 mg g(-1) (at 273 K and 1 bar) and 52 mg g(-1) (at 273 K and 0.15 bar), superior to those of the most known MOPs and porous carbons. The high physicochemical stabilities and appropriate isosteric adsorption heats as well as high CO2/N2 ideal selectivities endow these hierarchically porous carbon materials great potential in gas sorption and separation.

The mixed-metal title compound, BaCu1/3Ta2/3S3 [barium copper(II) tantalum(V) trisulfide], was prepared through solid-state reactions. The crystal structure adopts the BaTaS3 structure type and consists of face-sharing [MS6] (M = Ta,Cu) octahedra (point-group symmetry -3m.) that are condensed into infinite chains along [001]. Adjacent chains are linked through the barium cations (site symmetry -6m2), which exhibit a coordination number of twelve. The M site is occupied by 2/3 of TaV and 1/3 of CuII, whereby the average M—S distances are slightly longer than those of ordered BaTaS3. The classical charge balance of the title compound can be represented by [Ba2+] [(Ta/Cu)4+] [S2−]3.

Genome mining of the deep sea-derived Streptomyces atratus SCSIO ZH16 enabled the activation of a cyclodepsipeptide gene cluster and isolation of its cinnamic acid-bearing product, atratumycin (1). Atratumycin’s structure was elucidated on the basis of extensive spectroscopic experiments, X-ray data, and Marfey’s method; a plausible biosynthesis and tailoring modification of 1 are also proposed and investigated. Additionally, atratumycin is active against Mycobacteria tuberculosis H37Ra and H37Rv with MICs of 3.8 and 14.6 μM, respectively.

A new two-dimensional (2D) layered oxysulfide, namely, SrOCuSbS

The organic-inorganic lead halide perovskites are attractive materials for photovoltaic application. The most widely studied perovskites based on methyl ammonium organic cation are less likely to form an ideal high-symmetry configuration at room temperature, leading to the appearance of local lattice strain. Herein, this study reports a strategy for the construction of thermally stable cubic perovskites at room temperature through the incorporation of the larger organic cation dimethyl ammonium. Detailed characterization on the single crystals and thin films reveals the formation of cubic phase with the addition of a certain amount of dimethyl ammonium at room temperature. With the presence of dimethyl ammonium, the nonradiative recombination in perovskite is suppressed, showing a longer PL lifetime and hole diffusion length. The more efficient charge extraction leads to an improvement in the photocurrent density, and then the device efficiency from 17.1% to 18.6%, together with an enhanced thermal stability at 85 °C. The influence of incorporating a larger organic cation on the structural configuration, optical properties, charge extraction, as well as the photovoltaic performance is systematically investigated, which offers an alternative way to improve the intrinsic stability of hybrid perovskites.

The precipitation &delta, 18O-elevation gradients are important for paleoclimate, hydrology, and paleoelevation studies. The field setting for this research was the upper reaches of the Heihe River Basin within the Qilian Mountains in the Northern Tibetan Plateau. Three study sites were established along the Heihe main river. These sites were the Yingluoxia and Qilian hydrological stations and the Yeniugou meteorological station. The Yingluoxia hydrological station was the dividing point between the upper and middle reaches of the Heihe River Basin. The altitudes of these sites range from 1600 m to 3300 m. Summer precipitation is predominant with regard to the annual precipitation amount. By analysis of variance (ANOVA), the precipitation &delta, 18O data collected from the three sites were analyzed, spanning a year of precipitation data from 2007.10 to 2008.9. The results showed that the &delta, 18O-elevation gradient was not significant (&alpha, = 0.05) at a seasonal or annual scale in this region and the precipitation-weighted annual mean &delta, 18O was &minus, 7.1&permil, Mechanisms that have been proposed to explain this result consider the role of two processes, including (1) mixing of moisture sources, a process common in an arid and semiarid region, and (2) the absence of a mechanism for water vapor to climb along slopes in the precipitation system. Atmospheric water vapor mainly travels along the trend of the Qilian Mountains range rather than climbing it because this region is dominated by the westerlies and the trend of the Qilian mountains is geographically aligned to the NWW (north-west-west) direction. We demonstrated that, aside from the water vapor source, the spatial relationship between the water vapor transport pathway and the trend of the mountain range are the main driving factors associated with the stable isotope trends in precipitation. As a result, it is important to re-recognize the timing and location of groundwater recharge in the Heihe River Basin.

A new chalcogenide Na

Four new compounds, K2.4Ga2.4M1.6Q8 (M = Si, Ge; Q = S, Se), were successfully synthesized via a reactive flux method. All compounds crystallize in the tetragonal system of space group I4/mcm, and belong to the Tl2Se2 structure type (Pearson symbol tI16). The isostructural scaffold of the compounds feature [(Ga0.6/M0.4)Q4/2] one-dimensional chains separated by K+ ions. The chains are composed of edge-sharing [(Ga0.6/M0.4)Q4/2] tetrahedrons. Powder and glass samples were synthesized from solid state reactions with different annealing processes. The transport properties of crystalline K2.4Ga2.4Ge1.6S8 and K2.4Ga2.4Ge1.6Se8 were determined from optical absorption measurements to be wide band gap semiconductors (Eg = 3.5 eV for K2.4Ga2.4Ge1.6S8 and 2.7 eV for K2.4Ga2.4Ge1.6Se8). A red shift of the band gap energy in the glass samples was observed. K2.4Ga2.4Ge1.6S8 glass showed a wide transparent range from 0.6 µm to 10 µm and a high soften-temperature of 533 °C. First-principles calculations fitted well with the optical measurements, indicating that the Ge substitution is beneficial for narrowing the band gap.

In this paper the climate characteristics of the first date of ≤0 °C temperature are analyzed; furthermore, the farming responses to climate warming are discussed using a climate diagnosis analysis and the least squares methods, which are based on the daily minimum temperature data in East China from 1961 to 2009. It was found that over the past 50 years there has been a trend of the first date of ≤0 °C temperature being delayed at a rate of 1.6 days per 10 years; however, between 1961 and 1990 the first date of ≤0 °C temperature arrived early at a rate of 1.8 days per 10 years, and then was delayed at a rate of 3.3 days per 10 years. Furthermore, the average first date of ≤0 °C temperature is 30 October in northern regions, and the frequency of the first date of ≤0 °C temperature is greater in October and November than in other months; however, the boundary of the first date of ≤0 °C temperature shifts from south to north during September to December, and this has been especially evident since t...

Six isostructural antiperovskite-derived chalcohalides, Ba

Six new isostructural compounds, with the formulas La3Fe0.5GeSe7, La3MnGaSe7, Ce3Fe0.5SiSe7, Ce3Mn0.5SiSe7, Sm3Fe0.5SiSe7 and Sm3Mn0.5GeSe7, have been successfully synthesized via a molten salt method. Their structures are determined by single crystal X-ray diffraction and they crystallize in the Ce6Al3.33S14 structure type (space group: P63, Pearson symbol: hP24). Pure phases of the Ce3Fe0.5SiSe7, Ce3Mn0.5SiSe7, Sm3Fe0.5SiSe7 and Sm3Mn0.5GeSe7 compounds were obtained by solid state reaction and were characterized by powder X-ray diffraction (PXRD), scanning electron microscope (SEM), ultraviolet-visible-infrared (UV-vis-IR) absorbance spectroscopy, and magnetization measurements. The Ce3Fe0.5SiSe7 and Ce3Mn0.5SiSe7 compounds show paramagnetic domination accompanied by antiferromagnetic contributions, while the Sm3Mn0.5GeSe7 and Sm3Fe0.5SiSe7 compounds show anti-ferromagnetic phase transitions with Neel temperatures of 13 K and 24 K, respectively. Optical measurements reveal that all of the four compounds can absorb most of visible light. These four compounds also show photoelectric properties with the photocurrent densities of 81, 1.3, 1.8 and 0.8 μA cm−2, respectively.

The layered mixed anion compound with the formula [Li0.85Fe0.15OH][FeS] was synthesized via a facile hydrothermal method. [Li0.85Fe0.15OH][FeS], which is determined by single crystal X-ray diffraction and refined by the SHELXTL program, crystallizes in the tetragonal space group of P4/nmm (a = b = 3.6886(3) A, c = 8.915(1) A, V = 121.29(2) A3, Z = 2). The structure features alternatively packed anti-PbO-like [Li0.85Fe0.15OH] and anti-PbO [FeS] layers. The sample was characterized by Field Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscopy (HRTEM). Powder X-ray diffraction results confirm the phase purity of the as-synthesized crystals. Temperature-dependent measurements of magnetic susceptibility reveal the presence of a paramagnetic-to-ferromagnetic phase transition around 50 K, accompanied by the metal-to-semiconductor phase transition in the temperature-dependent resistance of the [Li0.85Fe0.15OH][FeS] single crystal.

2H MoS2 has been intensively studied because of layer-dependent electronic structures and novel physical properties. Though the metastable 1T MoS2 with the [MoS6] octahedron was observed from the microscopic area, the true crystal structure of 1T phase has not been determined strictly. Moreover, the true physical properties have not been demonstrated from experiments due to the challenge for the preparation of pure 1T MoS2 crystals. Here, we successfully synthesized the 1T MoS2 single crystals and re-determined the crystal structure of 1T MoS2 from single-crystal X-ray diffraction. 1T MoS2 crystalizes in space group P-3m1 with a cell of a = b = 3.190(3) {\AA} and c = 5.945(6) {\AA}. The individual MoS2 layer consists of MoS6 octahedron sharing edge with each other. More surprisingly, the bulk 1T MoS2 crystals undergo a superconducting transition of Tc = 4 K, which is the first observation of superconductivity in pure 1T MoS2 phase.

Nano TiO2 is investigated intensely due to extraordinary photoelectric performances in photocatalysis, new-type solar cells, etc., but only very few synthesis and physical properties have been reported on nanostructured TiO or other low valent titanium-containing oxides. Here, a core-shell nanoparticle made of TiO core covered with a ≈5 nm shell of amorphous TiO1+x is newly constructed via a controllable reduction method to synthesize nano TiO core and subsequent soft oxidation to form the shell (TiO1+x ). The physical properties measurements of electrical transport and magnetism indicate these TiO@TiO1+x nanocrystals are a type-ІІ superconductor of a recorded Tconset = 11 K in the binary Ti-O system. This unusual superconductivity could be attributed to the interfacial effect due to the nearly linear gradient of O/Ti ratio across the outer amorphous layer. This novel synthetic method and enhanced superconductivity could open up possibilities in interface superconductivity of nanostructured composites with well-controlled interfaces.

2H MoS

The mixed-metal sulfide compound with the formula Ba

Atratumycin is a cyclodepsipeptide with activity against Mycobacteria tuberculosis isolated from deep-sea derived Streptomyces atratus SCSIO ZH16NS-80S. Analysis of the atratumycin biosynthetic gene cluster (atr) revealed that its biosynthesis is regulated by multiple factors, including two LuxR regulatory genes (atr1 and atr2), two ABC transporter genes (atr29 and atr30) and one Streptomyces antibiotic regulatory gene (atr32). In this work, three regulatory and two transporter genes were unambiguously determined to provide positive, negative and self-protective roles during biosynthesis of atratumycin through bioinformatic analyses, gene inactivations and trans-complementation studies. Notably, an unusual Streptomyces antibiotic regulatory protein Atr32 was characterized as a negative regulator, the function of Atr32 is distinct from previous studies. Five over-expression mutant strains were constructed by rational application of the regulatory and transporter genes, the resulting strains produced significantly improved titers of atratumycin that were ca. 1.7&ndash, 2.3 fold greater than wild-type (WT) producer. Furthermore, the atratumycin gene cluster was successfully expressed in Streptomyces coelicolor M1154, thus paving the way for the transfer and recombination of large DNA fragments. Overall, this finding sets the stage for understanding the unique biosynthesis of pharmaceutically important atratumycin and lays the foundation for generating anti-tuberculosis lead compounds possessing novel structures.