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[Display omitted] • Zn-VO x -Co 2D ultra-thin nanosheets were developed as electrocatalysts for the first time. • Zn-VO x -Co composed of amorphous and crystalline phase with a heterostructure. • D-band center of metallic Co was optimized by dual-doping Zn and VO x elements. • Zn-VO x -Co revealed high HER activity with nearly 100% Faradaic efficiency. • The electrocatalytic mechanism was proposed based on experimental and DFT calculations. Designing cost-effective catalysts with high-activity and ultra-stability for hydrogen evolution reaction (HER) is important in the scaling-up of water electrolysis process for hydrogen production. Herein, a Zn-VO x -Co two-dimensional (2D) nanosheet with well-integrated heterostructure was successfully synthesized on carbon fiber paper (CFP) by a facile electrodeposition approach. Interestingly, the obtained nanosheets composed of amorphous VO x -Co and Zn-Co crystalline phases with a heterostructure. Density functional theory (DFT) calculations reveled that the dual-doping of Zn and VO x optimized d-band center of Co and balanced adsorption and desorption of H, which enhanced intrinsic electrocatalytic HER activity. As a result, the optimum catalyst achieved a current density of 10 mA cm−2 at an overpotential as low as 46 mV and long-term electrochemical stability over 36 h in 1 M KOH solution. This work opens a new avenue for designing electrocatalysts with unique crystalline-amorphous heterostructure by dual-doping to achieve tunable surface properties as well as d-band structure. [ABSTRACT FROM AUTHOR]

The fabrication methods for high performance pervaporation (PV) desalination membranes were complicated and difficult to be scaled-up. To address this issue, we developed a composite membrane using a porous polysulfone (PSF) membrane that was prepared by a conventional non-solvent induced phase inversion (NIPS) technology. The key was to design the PSF structure with a skinless, macro-void free and bi-continuous cross-sectional morphology for achieving an ultra-low transport resistance. This was done by incorporating non-solvent additives of polyvinylpyrrolidone (PVP) and propionic acid (PA) into the PSF polymer dope and regulating the temperature of the water coagulant. As a result, the PSF based PV composite membrane exhibited a high-water flux of 124.8 ± 3.2 kg/(m2·h) and a salt rejection of 99.9% when separating a 3.5 wt% NaCl solution at 70 °C. Moreover, a water flux of 71.3 ± 1.8 kg/(m2·h) was achieved for treating a high concentrated NaCl solution of 20 wt%. To our best knowledge, these PV membrane desalination performances overshadowed all reported PV composite membranes using substrates fabricated by the NIPs method. Most importantly, the easy-to-scale-up membrane fabrication method, as well as the excellent PV desalination performance, indicated a great potential for industrial applications. Schematic diagrams of the water transfer processes across the high performance composite PV membrane. [Display omitted] • Optimization the polysulfone (PSF) substrate to obtain a macro-void free, inter-connected pores, and skinless structure by changing the casting solution composition and the temperature of coagulation bath. • Evaluation the composite membranes pervaporation (PV) performance and the substrate structure effect on the gas transport resistance. • The resistance to swelling polyvinyl alcohol (PVA) layer delamination and the long-term operational stabilities of the composite membrane. • Effects of temperature and salt concentration on the composite membranes desalination properties. • The high-water flux PV composite membrane, with a easy-to scale-up porous substrate, demonstrated a great potential for its composite PV membrane commercialization. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two versatile 3D polymers have been synthesized with d10 metal ions. [•] IR, PXRD, TG technique for the polymers. [•] X-ray single-crystal structure analyses and discussion for the polymers. [•] The polymers exhibit interesting luminescence properties in solid state. [ABSTRACT FROM AUTHOR]

Transition metal hydroxides, due to their low cost and high theoretical capacity, are promising candidates for supercapacitors. However, the lower conductivity of hydroxides usually results in devices exhibiting poor specific capacity. Here, Ni(OH) 2 @Ni 12 P 5 electrodes are designed and prepared, showing great potential for applications. This composite electrode, prepared by simple phosphating treatment and electrodeposition. Compared with the Ni(OH) 2 prepared by direct deposition, this rationally designed electrode exhibits more excellent electrochemical properties. The prepared Ni(OH) 2 @Ni 12 P 5 electrode exhibits a good area specific capacitance of 15.89 F•cm−2 at a current density of 10 mA•cm−2, which is 2.93 times higher than that of the Ni(OH) 2 electrode (5.43 F•cm−2). In addition, the assembled Ni(OH) 2 @Ni 12 P 5 //AC asymmetric supercapacitor exhibits an energy density of 0.38 mWh•cm−2 at a power density of 8.00 mW•cm−2. Therefore, this work provides a new strategy for the synthesis of high-performance supercapacitor electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel adsorbent (MPN-Bet) with antibacterial and magnetic properties was synthesized via the functionalization of peanut husk (a low-cost material) with Fe 3 O 4 and betaine. Results from the characterization studies confirmed that the enhanced efficiency of peanut husk as an adsorbent was due to the alteration in its surface nature and physicochemical properties by these modification agents. MPN-Bet possessed good efficiency for the sequestration of trimethoprim (TMP) from solution. The experimental adsorption capacity of 20.3 ± 0.9 mg g−1 was recorded with the process being exothermic in nature. The physisorption and chemisorption processes were found play active roles in the adsorption process albeit the latter being the dominant. Regeneration studies showed MPN-Bet loaded TMP was highly reusable after treatment with 0.1 mol L−1 NaCl. The assessment of the antibacterial properties of MPN-Bet indicated that MPN-Bet could effectively limit the growth of E. coli and S. aureus without causing damage to other living organisms (i.e. biocompatible). These excellent properties of MPN-Bet coupled with its good reusability, high stability and easy separation from mixtures promote its prospects for practical wastewater remediation. [Display omitted] • A novel biocomposite (MPN-Bet) was synthesized via a simple synthetic route. • MPN-Bet has mesoporous pore structure and other unique physicochemical features. • MPN-Bet is highly efficient for the removal of trimethoprim (TMP) in solution. • The chemisorption was the major underlying mechanism for the uptake of TMP. • MPN-Bet possesses antibacterial properties towards E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

The chemical form and subcellular and molecular distribution of cadmium (Cd) in the roots and leaves was investigated in two rice genotypes: the low Cd-accumulating ‘‘Guangyuanzhan No. 3’, and the high Cd-accumulating ‘‘Zhenguiai.’’ Elevated Cd level in the medium caused a significant increase in Cd concentration in all parts of the roots and leaves. The soluble fractions in leaves and roots of ‘Zhenguiai’ contained a higher proportion of the Cd than those in ‘Guangyuanzhan No. 3’. Furthermore, ‘Zhenguiai’ had a higher proportion of de-ionized water and 80% ethanol-extractable Cd, which is the most mobile Cd among its various chemical forms. Following gel filtration of the soluble fraction of leaf and root extracts of both genotypes, a compound with a molecular weight of ∼3 kDa, probably comprising phytochelatins (PCs), was the major Cd-binding component. The Cd concentrations in the fractions from the roots of ‘Zhenguiai’ were noticeably higher than those of ‘Guangyuanzhan No. 3’, which possibly resulted in the latter cultivar having a lower Cd mobility in the roots and less Cd translocation from the roots to the aboveground parts. [ABSTRACT FROM PUBLISHER]

Abstract: Complex (oxy)fluorides K2TiF6, K2TiOF4, K3TiOF5 and K7Ti4O4F7 have been successfully synthesized for the first time through a controllable solvothermal route involving different solvents, for example, methanol, methanol–H2O and methanol–H2O2. The as-prepared products were characterized by X-ray powder diffraction, N2 surface area adsorption, scanning electron microscope, Fourier transform infrared spectroscopy, UV–vis absorption spectra and X-ray fluorescence. The influences of reaction conditions such as the ratio of methanol to H2O2 or methanol to H2O, reaction temperature on the phase, crystallizability and purity of the (oxy)fluorides products were discussed in detail. Meanwhile, the photocatalytic behaviors of the as-prepared K2TiF6, K2TiOF4, K3TiOF5 and K7Ti4O4F7 were evaluated by degradation of rhodamine B molecules, and the results showed that all of the products possessed photocatalytic activities in the order of K2TiOF4 >K2TiF6 >K7Ti4O4F7 >K3TiOF5 at room temperature under the UV light. [Copyright &y& Elsevier]

Abstract: Deformation textures and recrystallization textures of ultrafine grains pure copper produced by asymmetrical accumulative roll-bonding (AARB) and symmetrical accumulative roll-bonding (ARB) respectively were investigated using X-ray diffraction (XRD). It was found that dominant deformation textures of copper after 98.4% strain are {100}<110> shear texture by AARB and {211}<111> copper texture by ARB, a mixed “deformation–recrystallization” texture is observed during the first stage of recrystallization, dominant recrystallization texture is {001}<100>cube texture in samples produced respectively by AARB and ARB. We suggest that deformation textures and recrystallization textures are controlled by the crystal structures and deformation methods of samples, some unusual properties in ultrafine grains pure copper are possibly unstable. [Copyright &y& Elsevier]

Superoxide dismutases (SODs) constitute the first line of cellular defense against oxidative stress in plants. SODs generally occur in three different forms with Cu/Zn, Fe, or Mn as prosthetic metals. We cloned the full-length cDNA of the Thellungiella halophila Cu/Zn-SOD gene ThCSD using degenerate RT-PCR and rapid amplification of cDNA ends (RACE). Sequence analysis indicated that the ThCSD gene (GenBank accession number EF405867) had an open reading frame of 456 bp. The deduced 152-amino acid polypeptide had a predicted molecular weight of 15.1 kDa, an estimated pI of 5.4, and a putative Cu/Zn-binding site. Recombinant ThCSD protein was expressed in Escherichia coli and assayed for SOD enzymatic activity in a native polyacrylamide gel. The SOD activity of ThCSD was inactivated by potassium cyanide and hydrogen peroxide but not by sodium azide, confirming that ThCSD is a Cu/Zn-SOD. Northern blotting demonstrated that ThCSD is expressed in roots, stems, and leaves. ThCSD mRNA levels increased by about 30-fold when plants were treated with sodium chloride (NaCl), abscisic acid (ABA), and indole-acetic acid (IAA) and by about 50-fold when treated with UVB light. These results indicate that ThCSD is involved in physiological pathways activated by a variety of environmental conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Maternal exposure to DBP induces earlier puberty of male offspring. • DBP not only activates the HPG axis, but also affects on Leydig cells. • DBP damages the reproductive system of adult male offspring. Di-n-butyl phthalate (DBP) is considered as a potential modifier of puberty. However, different results indicate that DBP plays an accelerated, delayed, or neutral role in the initiation of puberty. Furthermore, whether the effect of DBP on puberty will disrupt the function of reproductive system in the adults is still ambiguous. Therefore, we aimed to investigate the effect of maternal exposure to DBP on the onset of puberty in male offspring mice and the subsequent changes in the development of reproductive system. Here, pregnant mice were treated with 0 (control), 50, 250, or 500 mg/kg/day DBP in 1 mL/kg corn oil administered daily by oral gavage from gestation day (GD) 12.5 to parturition. Compared with the control group, the 50 mg/kg/day DBP group accelerated puberty onset and testicular development were quite remarkable in male offspring mice during early puberty. Furthermore, in 22-day male offspring mice, 50 mg/kg/day DBP induced increased levels of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone in serum, and promoted the expression of steroidogenesis-related genes in the testes. Testicular Leydig cells (LCs) were isolated from the testes of 3-week-old mice and treated with 0 (control), 0.1, 1 mM monobutyl phthalate (MBP, the active metabolite of DBP) for 24 h. Consistent with the in vivo results, the expression of steroidogenesis-related genes and testosterone production were increased in LCs following exposure to 0.1 mM MBP. In adulthood, testes of the male offspring mice exposed to all doses of DBP exhibited adverse morphology compared with the control group. These results demonstrated that maternal exposure to 50 mg/kg/day DBP induced earlier puberty and precocious development of the testis, and eventually damaged the reproductive system in the later life. [ABSTRACT FROM AUTHOR]

Background: Ophiocordyceps sinensis, which is only naturally found in the high-elevation extreme environment of the Tibetan Plateau, has been used in traditional Chinese medicine. Information concerning the evolutionary and geologic context of O. sinensis remains limited, however. Methods: We constructed the high-quality genome of O. sinensis and provided insight into the evolution and ecology of O. sinensis using comparative genomics. Results: We mapped the whole genome of the anamorph/asexual form Hirsutella of O. sinensis using Illumina and PacBio sequencing technologies and obtained a well assembled genome of 119.2 Mbp size. Long-read Single Molecule Real Time (SMRT) sequencing technology generated an assembly with more accurate representation of repeat sequence abundances and placement. Evolutionary analyses indicated that O. sinensis diverged from other fungi 65.9 Mya in the Upper Cretaceous, during the uplift of the Tibetan Plateau. Gene family expansions and contractions in addition to genome inflation via long terminal repeat (LTR) retrotransposon insertions were implicated as an important driver of O. sinensis divergence. The insertion rate of LTR sequences into the O. sinensis genome peaked ~ 30–40 Mya, when the Tibetan Plateau rose rapidly. Gene Ontology (GO) enrichment analysis suggested that O. sinensis contained more genes related to ice binding compared to other closely related fungi, which may aid in their adaptability to the cold Tibetan Plateau. Further, heavy metal resistance genes were in low abundance in the O. sinensis genome, which may help to explain previous observations that O. sinensis tissues contain high levels of heavy metals. Conclusions: Our results reveal the evolutionary, geological, and ecological context for the evolution of the O. sinensis genome and the factors that have contributed to the environmental adaptability of this valuable fungus. These findings suggest that genome inflation via LTR retrotransposon insertions in O. sinensis coincided with the uplift of the Tibetan Plateau. LTRs and the specific genetic mechanisms of O. sinensis contributed to its adaptation to the environment on the plateau. [ABSTRACT FROM AUTHOR]

The construction of multiple fluorescent nanosensors for intracellular studies is a challenging task because spectral overlap of indicator probes can lead to cross-talk and mutual interference. This work describes biodegradable nanosensors that can simultaneously measure three intracellular parameters (temperature, pH and oxygen concentration). Bovine serum albumin (BSA) is selected as the scaffold to construct the triple nanosensor by covalent immobilization four fluorophores on BSA. The following luminophores were used: (a) fluorescein as a probe for pH values, (b) a platinum(II) porphyrin complex for oxygen; (c) a europium(III) clathrate complex for temperature, and (d) a rhodamine B as a reference dye. The nanoparticles have a size of 20 nm and show excellent biocompatibility and good brightness. The nanosensors were used for ratiometric imaging of intracellular pH values, oxygen and temperature in HeLa cells. The triple nanosensor responds reversibly and this can be used for real-time tracing of these key parameters. Owing to their biodegradable feature, the use of this kind of triple nanosensor reduce the stress on cellular activities because less nanosensors can be used to gather the total information. [ABSTRACT FROM AUTHOR]

Background: Children in poor areas show significant growth retardation that does not improve with an adequate supply of energy and nutrients, which may be related to asymptomatic intestinal infection caused by poor sanitation. Our objective was to explore the mechanism of intestinal inflammation inhibiting growth in the setting of asymptomatic colitis.Methods: Forty-eight 3-week-old Wistar rats were randomly divided into three groups: the control group, colitis group (with asymptomatic colitis induced by 2.5% trinitrobenzenesulphonic acid) and pair-fed group (daily food intake matched to the pair in the colitis group). The linear growth was assessed, and the plasma levels of hormone and systemic cytokines were detected and compared by independent two-sample t-test or one-way ANOVA among groups.Results: At d5, the increases in the body length of the control, colitis and pair-fed groups were 1.65 ± 0.34 cm, 1.10 ± 0.30 cm and 1.38 ± 0.26 cm, respectively, and the increase in the body length in the colitis group was significantly less than that in the control group (P < 0.05). There were significant differences in the levels of hormone and cytokines among three groups (P < 0.05). Compared with the control group, rats in the colitis group exhibited linear growth failure, as well as higher expression of calprotectin, tumour necrosis factor-α, interleukin-6 and insulin-like growth factor binding protein 2, lower insulin-like growth factor-1 and insulin-like growth factor binding protein 3, and lower expression of nuclear factor kappa B in hepatocytes.Conclusions: In addition to undernutrition, the systemic inflammatory response caused by asymptomatic colitis may inhibit the linear growth of rats by its influence on the insulin-like growth factor/insulin-like growth factor binding protein axis. [ABSTRACT FROM AUTHOR]

We demonstrated a sub-200-fs polarization-maintaining Yb-fiber laser amplifier based on chirped-pulse amplification (CPA) technology with high energy and stability. The seeding laser pulses were picked to 1 MHz from a nonlinear polarization evolution (NPE) self-similar mode-locked Yb-fiber laser oscillator at 40.3 MHz. A specially designed chirped fiber Bragg grating (CFBG) was employed as the pulse stretcher, which provide compensation for higher order dispersion introduced by grating compressor. Laser pulse as short as 153 fs with energy of 32 μJ was obtained after the compressor, which corresponds to a peak power of 209 MW. The measured output power fluctuation of root mean square was 0.64% in 24 h and the M2 factor was 1.3. It shows a great potential in many applications such as scientific researches, medical therapy, and industrial micromachining. [ABSTRACT FROM AUTHOR]