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Quasi-phase matching (QPM) enables flexible and efficient second-order nonlinearity ranging from bulk nonlinear crystals to integrated nonlinear photonic devices. Here, we propose a QPM nonlinear photonic device constructed using monolayer transition-metal dichalcogenide (TMDC) arrays attached on a silicon nitride waveguide. QPM second harmonic generation comes from a nonlinear interaction between evanescent fields of fundamental-frequency and second-harmonic guided modes with periodical monolayer TMDC arrays. Dispersions of the device can be tuned by changing the geometric parameters of the waveguide while the nonlinear overlap integral and the QPM condition can be controlled through the distribution of TMDC arrays. Our design provides a practical way to efficiently shape second-order nonlinearities in complementary metal–oxide–semiconductor-compatible photonic platforms.

Combining chiral molecules and covalent organic frameworks (COFs) with ordered pores can result in chiral COFs, which may be employed in the fields of chiral chemistry. In this study, we constructed a novel carboxyl-functionalized COF TpBD-3COOH first and then integrated a chiral molecule, heptakis (6-amino-6-deoxy)-β-CD (Am7CD), into TpBD-3COOH to obtain TpBD-Am7CD. Comparing TpBD-3COOH with TpBD-Am7CD, it could be observed that chiral selectivities improved significantly after decorating TpBD-3COOH with Am7CD in the adsorption experiment. Meanwhile, TpBD-Am7CD exhibited similar chiral selective abilities as the previously reported β-CD COF when it was employed to adsorb amino acid enantiomers, while the content of Am7CD was much less than that in β-CD COF. This indicated that the framework of TpBD-3COOH enhanced the chiral selective ability of Am7CD, which would be a great chiral carrier material for further application. This work provides a new insight for establishing materials for application in the chiral recognition field. Besides, TpBD-Am7CD resulted in an insoluble powder, which endowed this material with the possibility to be an adsorbent and a stationary phase in chromatography.

Resveratrol (RSV) is a natural polyphenol with anti-obesity effects. However, the mechanisms of anti-obesity remain unclear due to its low bioavailability. Recent evidence demonstrates that gut microbiota plays a key role in obesity. This spurred us to investigate whether the anti-obesity effects of RSV are related to modulations in the gut microbiota and metabolic functions. Here, RSV significantly improved metabolic phenotype and intestinal oxidative stress in the high-fat diet (HFD)-fed mice. A multi-omics approach was used to systematically profile the microbial signatures at both the phylogenetic and functional levels using 16S rRNA gene sequencing and metagenome. At the phylogenetic level, RSV treatment significantly modulated the gut microbiota composition in HFD-fed mice, characterized with increased Blautia abundance and decreased Desulfovibrio and Lachnospiraceae_NK4A136_group abundance. At the functional level, RSV significantly decreased the enrichment of pathways linked to host metabolic disease and increased the enrichment of pathways involved in the generation of small metabolites. Besides, the fecal microbiota transplantation experiment showed anti-obesity and microbiota-modulating effects similar to those observed in the oral RSV-feeding experiment. Furthermore, metabolomic analysis and antibiotic treatment verified that 4-hydroxyphenylacetic acid (4-HPA) and 3-hydroxyphenylpropionic acid (3-HPP) were the two gut metabolites of RSV, which contribute to improving lipid metabolism in vitro. Moreover, the content of 4-HPA and 3-HPP exhibited strong correlation with the intestinal oxidative state. We concluded that the RSV-mediated alteration of gut microbiota, related gut metabolites and redox state of the intestinal environment contributed to prevention of metabolic syndrome in HFD-fed mice.

The development of high-efficiency non-noble metal catalysts for the oxygen reduction reaction (ORR) is of paramount significance to sustainable energy-conversion technologies. Herein, a three-dime...

Globally increasing trace metal contamination of soils requires a better mechanistic understanding of metal-stress impacts on microbially mediated nutrient cycling. Herein, a 5-month laboratory experiment was employed to assess the effects of cadmium (Cd) on soil microbial N-cycling processes and associated functional gene abundance, with and without urea amendment. In non-N-amended soils, Cd progressively stimulated microbial populations for N acquisition from initial dissolved organic N (DON) to later recalcitrant organic N. The acceleration of N catabolism was synchronously coupled with C catabolism resulting in increased CO2/N2O fluxes and adenosine triphosphate (ATP) contents. The abundance of microbes deemed inefficient in N catabolism was gradually repressed after an initial stimulation period. We posit that enhanced exergonic N processes diminished the need for endergonic activities as a survival strategy for N communities experiencing metal stress. With urea amendment, Cd exhibited an initial stimulation effect on soil nitrification and a later a promotion effect on mineralization, along with an increase in the associated microbial populations. In N-amended soils, Cd accelerated N/C transformation processes, but decreased N2O and CO2 fluxes by 19 and 14%, respectively. This implies that under eutrophic conditions, Cd synchronously altered microbial C/N metabolism from a dominance of catabolic to anabolic processes. These results infer a nutrient-based adjustment of microbial N-cycling strategies to enhance their metal resistance.

Covalent organic frameworks (COFs), a type of crystalline polymers, have attracted increasing interest because of their controllability of geometry and functionality. Featuring infinitely extended networks and tremendous interaction sites, COFs emerge as a potential platform for separation science. Here, a novel chiral COF (β-CD COFBPDA) constructed by the imine condensation of 4,4′-biphenyldicarboxaldehyde and heptakis(6-amino-6-deoxy)-β-cyclodextrin was introduced into an electrochromatographic system via a photopolymerization method and applied to the separation of enantiomers. The structure and properties of as-synthesized β-CD COFBPDA were investigated by powder X-ray diffraction (PXRD) patterns, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and N2adsorption-desorption isotherms. It was proved that β-CD COFBPDA was provided with larger pore size and BET surface area. The β-CD COFBPDA coating endowed the chiral stationary phase with superior three-dimensional orientation, and realized satisfactory separation with improved selectivity and column efficiency for a dozen racemic drugs. Under the optimized conditions, homatropine, ondansetron, metoprolol, terbutaline, tulobuterol, and promethazine were all baseline separated with resolution values of 2.24, 2.03, 1.65, 1.62, 1.60, and 1.58, respectively. The results indicate the high perspective of COF modified stationary in enantioseparation.

Investigating noble-metal-free and earth-abundant cocatalysts has emerged as a promising and challenging issue for improving the photocatalytic hydrogen production efficiency. In this work, a novel...

Non-noble metal catalysts for photo/electrocatalytic water splitting are quite feasible for solving the problems of growing energy demand and environmental pollution. In this paper, noble-metal free Mn-Cd-S@amorphous-Ni3S2 hybrid catalyst (MCS@a-Ni3S2) with bifunctionality of photocatalytic hydrogen evolution and electrocatalytic OER is designed and prepared by simple hydrothermal method. The characterization results show that Mn-Cd-S was composed of cubic manganese sulfide and manganese doped cadmium sulfide, and amorphous Ni3S2 coating on the surface of Mn-Cd-S. The resultant Mn-Cd-S@amorphpus-Ni3S2 catalyst presents good stability and a high photocatalytic H2 evolution rate of 12,069.27 μmolh−1 g−1. Besides, both Mn-Cd-S and Mn-Cd-S@amorphpus-Ni3S2 show good OER property with overpotential of 333 mV. Mn-Cd-S@amorphpus-Ni3S2 shows more favorable kinetics than that of Mn-Cd-S for OER. Moreover，the mechanism of the enhanced photo/electrocatalytic performance is investigated in detail. This work provides references for developing the catalysts with both photocatalytic and electrocatalytic properties.

Circular RNA (circRNA) is a novel subclass of noncoding-RNA molecules that participate in development and progression of a variety of human diseases via sponging microRNAs (miRNAs), but the role of circRNAs in Hashimoto’s thyroiditis (HT) has not been defined. In this study, peripheral blood samples from five patients with HT and five healthy volunteers were investigated by Illumina HiSeq Sequencer. A total of 627 differentially expressed circRNAs including 370 upregulated and 257 downregulated ones were identified in HT patients. Four upregulated circRNAs indicated the same rising tendency toward sequencing results. The expression of hsa_circ_0089172 was upregulated and correlated positively with the serum level of the thyroid peroxidase antibody. Two perfectly matched binding sites of miR-125a-3p were found in hsa_circ_0089172 sequences with bioinformatics tools. The expression of miR-125a-3p was decreased in the HT patients and correlated inversely with an elevated level of hsa_circ_0089172. Moreover, knockdown of hsa_circ_0089172 resulted in an increase of the expression of miR-125a-3p in vitro. Receiver operating characteristic (ROC) curve analysis suggested that hsa_circ_0089172 had significant value in HT diagnosis. Taken together, these results demonstrate that hsa_circ_0089172 as a potential diagnostic biomarker of HT and may play a crucial role in the pathogenesis of HT via sponging miR-125a-3p. Keywords: circRNA, Hashimoto’s thyroiditis, sponge, next-generation sequencing

This study investigated effects of loadings of rice straw (Oryza sativa L.) cellulose nanofibrils (CNFs) defibrillated using the high-pressure homogenization technique on tensile property, glass transition temperature, and thermal stability of polyvinyl alcohol (PVA) matrix. CNF loadings had five percentage levels by weight of final composite, i.e. 0, 0.03, 0.08, 0.12, and 0.17%, respectively. A freezing-and-thawing cycle method cast PVA/CNF-mixed and PVA-only films. Experimental results showed that PVA films with 0.03% CNFs had average tensile strength of 50.8 MPa and modulus of 707 MPa, which were 32 and 21% higher than neat PVA ones, respectively. In addition, the glass transition temperature values of PVA/CNF-mixed film increased from 51.6% to 82.6% with increasing the amount of CNFs. The thermogravimetric analysis showed that PVA/CNF-mixed films had significantly higher thermal stability than PVA-only films. The shift of the O–H stretching vibration peak in PVA/CNF-mixed films indicated a good compatibility between CNFs and PVA matrix.

Dopaminergic modulation of corticostriatal transmission is critically involved in reward-driven behaviors. This modulation is mainly mediated by dopamine D1 receptors (D1Rs) and D2Rs, which are highly expressed in medium spiny neurons (MSNs) of the dorsomedial striatum (DMS), a brain region essential for goal-directed behaviors and addiction. D1Rs and D2Rs are also present at presynaptic cortical terminals within the DMS. However, it is not known how addictive substances alter the glutamatergic strength of striatal synapses expressing presynaptic dopamine receptors. Using cell type-specific Cre mice in combination with optogenetic techniques, we measured glutamatergic transmission at D1R- or D2R-expressing afferents to DMS MSNs. We found larger excitatory postsynaptic currents at the synapses between the extra-striatal D2R-expressing afferents and D1R-expressing MSNs (D2→D1), as compared with those observed at the other tested synapses (D1→D1, D1→D2, and D2→D2). Additionally, excessive alcohol consumption induced a long-lasting potentiation of glutamatergic transmission at the corticostriatal D2→D1 synapse. Furthermore, we demonstrated that activation of postsynaptic, but not presynaptic, D2Rs inhibited corticostriatal transmission in an endocannabinoid-dependent manner. Taken together, these data provide detailed information on the mechanisms underlying dopamine receptor-mediated modulation of brain reward circuitry.

High hydrostatic pressure (HHP) processing has become a commercial success in fruit and vegetable processing. Herein, the effects of HHP and high-temperature short-time (HTST) processing on metabolic profiling in tomato juice was evaluated by UPLC-MS/MS, HPLC, and GC-MS; a total of 425 metabolites, 14 carotenoids, and 56 volatile compounds were identified in tomato juice. HHP processing affects the composition of the juice less than HTST processing, considering 4 and 33 differential metabolites discriminated after HHP and HTST processing, respectively. The total lycopene and carotenoid contents in tomato juice increased after HHP processing, while the β-carotene and lycopene contents decreased after HTST processing. Further, more volatile compounds and higher contents of aldehydes that contribute to green aroma and lower contents of alcohols were observed after HHP and HTST processing, respectively. These findings provide a comprehensive understanding of the advantages of HHP processing on metabolite profiles in tomato juice.

Uncontrolled drug-seeking and -taking behaviors are generally driven by maladaptive corticostriatal synaptic plasticity. The orbital frontal cortex (OFC) and its projections to the dorsomedial striatum (DMS) have been extensively implicated in drug-seeking and relapse behaviors. The influence of the synaptic plasticity of OFC projections to the DMS (OFC→DMS) on drug-seeking and -taking behaviors has not been fully characterized. To investigate this, we trained rats to self-administer 20% alcohol and then delivered an in vivo optogenetic protocol designed to induce long-term potentiation (LTP) selectively at OFC→DMS synapses. We selected LTP induction because we found that voluntary alcohol self-administration suppressed OFC→DMS transmission and LTP may normalize this transmission, consequently reducing alcohol-seeking behavior. Importantly, ex vivo slice electrophysiology studies confirmed that this in vivo optical stimulation protocol resulted in a significant increase in excitatory OFC→DMS transmission strength on day two after stimulation, suggesting that LTP was induced in vivo. Rat alcohol-seeking and -taking behaviors were significantly reduced on days 1-3, but not on days 7-11, after LTP induction. Striatal synaptic plasticity is modulated by several critical neurotransmitter receptors, including dopamine D1 receptors (D1Rs) and adenosine A2A receptors (A2ARs). We found that delivery of in vivo optical stimulation in the presence of a D1R antagonist abolished the LTP-associated decrease in alcohol-seeking behavior, whereas delivery in the presence of an A2AR antagonist may facilitate this LTP-induced behavioral change. These results demonstrate that alcohol-seeking behavior was negatively regulated by the potentiation of excitatory OFC→DMS neurotransmission. Our findings provide direct evidence that the OFC exerts "top-down" control of alcohol-seeking behavior via the DMS.

Diversity and community composition of soil microorganisms along the elevation climosequences have been widely studied, while the microbial metabolic potential, particularly in regard to carbon (C) cycling, remains unclear. Here, a metagenomic analysis of C related genes along five elevations ranging from 767 to 4190 m at Mount Kilimanjaro was analysed to evaluate the microbial organic C transformation capacities in various ecosystems. The highest gene abundances for decomposition of moderate mineralizable compounds, i.e. carbohydrate esters, chitin and pectin were found at the mid-elevations with hump-shaped pattern, where the genes for decompositions of recalcitrant C (i.e. lignin) and easily mineralizable C (i.e. starch) showed the opposite trend (i.e. U-shaped pattern), due to high soil pH and seasonality in both low and high elevations. Notably, the gene abundances for the decompositions of starch, carbohydrate esters, chitin and lignin had positive relationships with corresponding C compounds, indicating the consistent responses of microbial functional profiles and metabolites to elevation climosequences. Understanding of adaptation of microbial communities, potential function and metabolites to elevation climosequences and their influencing factors provided a new insight for the regulation of terrestrial C storage.

The critical prerequisite for realizing the industrial application of photocatalytic technology lies on developing efficient photocatalyst through reasonable and large-scale modification strategy. Herein, the rapid and solvent-free high-energy ball-milling procedure was adopted to modify graphitic carbon nitride (g-C3N4) on a large-scale by phosphorus (P) atom doping and molybdenum phosphide (MoP) decorating. It is confirmed that P doping can introduce a mid-gap state in the band gap of g-C3N4, broadening the light responsive region and enhancing the electrical conductivity of g-C3N4. The Mo N bond at the interface of P-doped g-C3N4 and MoP acting as electrons “delivery channels” facilitates the charge transfer from P-doped g-C3N4 to MoP, while the Schottky barrier promotes the separation of photocarriers. As a result, the optimized P-doped g-C3N4/MoP photocatalyst performs an improved H2 evolution rate of 4917.83 μmol·g−1·h−1 and a favorable H2 production stability. This work offers a replicable prototype on adopting high-energy ball-milling to modify photocatalyst.

Improving the photocatalytic property of metal-free photocatalyst is still a challenging work. Herein, a novel high-efficiency molybdenum sulfide (MoS2)-modified metal-free graphitic carbon nitride (g-C3N4)/black phosphorus (BP) photocatalyst (MCN/BP/MS) was synthesized on a large scale via high-energy ball milling process. The optimized MCN/BP/MS exhibits the excellent hydrogen evolution rate of 2146.8 µmol·g−1·h−1, and hexavalent chromium (Cr(Ⅵ)) reduction activity with an apparent rate constant of 0.1464 min−1 and a degradation rate of 100% in 25 min. Detailed characterizations and mechanism research verified that the significantly improved photocatalytic activity of MCN/BP/MS mainly profited from the matched band structure, enhanced light absorption, intense interface contact, as well as the type-Ⅰ/Z hybrid charge transfer mechanism, which gave rise to a consecutive multistep charge migration, thus the photocarriers transfer and separation can be greatly promoted, and the photogenerated electrons with high reducing capacity can be preserved. This work not only provides a high-efficiency g-C3N4-based noble-metal-free photocatalyst, but also affords a beneficial inspiration for improving the photocatalytic property of the metal free photocatalyst.

The aim of this study is to examine the wettability and thermal properties of individual bamboo fibers after alkali treatment. The individual bamboo fibers were treated by sodium hydroxide (NaOH) solution with varying concentrations (6, 8, 10, 15 and 25%) followed by freeze-drying treatment. The surface analysis of alkali-treated individual bamboo fibers was characterized by atomic force microscope. Water droplet on the individual fiber surface was observed with drop shaper analyzer and the contact angles on fiber surface were also measured. Thermal properties were further studied by thermogravimetric analysis. The results indicated that alkali treatment resulted in the increase in surface roughness of individual bamboo fibers. Alkali treatment with low NaOH concentration could enhance the wettability of treated individual bamboo fibers, and while the wettability was reduced with alkali treatment at high concentration (25%). Thermal analysis revealed that the onset of decomposition and the maximum decomposition were moved to higher temperature after alkali treatment at low NaOH concentrations (6, 8, and 10%), suggesting the improvement in the thermal stability of treated individual bamboo fibers, while the thermal stability was compromised after alkali treatment at higher concentrations (15 and 25%).

In this paper, the flat tungsten coatings with uniform grains were prepared via electrolytic tungsten at 1173 K in ternary molten salt system formed by tungstate, tungsten oxide and different mass fractions of ZrO2. Dense tungsten coatings containing the second phase of ZrO2 were obtained by constant direct current electrodeposition in molten salt, and the coatings have preferential growth orientation along the (2 1 1) crystal plane. These coatings were characterized via X–ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and laser scanning confocal microscope (LSCM). The results show that W-ZrO2 coating obtained at Na2WO4-WO3-ZrO2. In addition, the existence of zirconia in molten salt reduced the coating roughness from 13.567 μm to 3.017 μm, the current efficiency was lost from 84.15% to 70.76%, and the grains became fine and uniform. What’s more, the mechanical properties and thermal cycle performance of the coating have been effectively improved. To further illustrate the electrochemical process, the electrochemical behavior of tungsten ions and zirconium ions during the electrodeposition was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). The results indicated that the reduction reactions of tungsten ions and zirconium ions are divided into two steps, and the reaction processes are as follows: W(VI) → W(IV) → W, Zr(IV) → Zr(II) → Zr.

Accumulated evidence suggests that the dorsomedial striatum (DMS) of the basal ganglia plays an essential role in pathological excessive alcohol consumption. The DMS receives multiple glutamatergic inputs. However, whether and how alcohol consumption distinctly affects these excitatory afferents to the DMS remains unknown. Here, we used optogenetics to selectively activate the rat medial prefrontal cortex (mPFC) and basolateral amygdala (BLA) inputs in DMS slices, and measured the effects of alcohol consumption on glutamatergic transmission in these corticostriatal and amygdalostriatal circuits. We found that excessive alcohol consumption increased AMPA receptor- and NMDA receptor (NMDAR)-mediated neurotransmission, as well as the GluN2B/NMDAR ratio, at the corticostriatal input to the DMS. The probability of glutamate release was increased selectively at the amygdalostriatal input. Interestingly, we discovered that paired activation of the mPFC and BLA inputs using dual-channel optogenetics induced robust long-term potentiation (LTP) of the corticostriatal input to the DMS. Taken together, these results indicate that excessive alcohol consumption potentiates glutamatergic transmission via a postsynaptic mechanism for the corticostriatal input and via a presynaptic mechanism for the amygdalostriatal input. These changes may in turn contribute to pathological alcohol consumption.

Background: Ascorbic acid (Asc) is one of the most abundant antioxidants and it serves as a major contributor to protect plants against oxidative damage. Plants use two enzymes that participate in the metabolic recycling of Asc. One of these two enzymes is dehydroascorbate reductase (DHAR). It directly regenerates Asc from its oxidized state and thus prevents Asc from being irreversibly hydrolyzed to 2, 3-diketogulonic acid. This study aimed to examine whether over-expression of DHAR leads to an enhanced oxidative stress tolerance in tobacco plants. Results: In this study, we functionally characterized a novel JcDHAR gene from Jatropha curcas and found via quantitative RT-PCR analysis that JcDHAR can be induced with H2O2, salt and PEG stresses. The DHAR activities of transgenic tobacco plants increased from 2.0 to 5.3 fold compared to wild-type plants. As a result, the transgenic plants displayed enhanced tolerance to oxidative stress. Conclusions: Our results indicate that JcDHAR expression can effectively enhance the tolerance to oxidative stress in plants.

Hypertension is one of the most prevalent diseases worldwide. Increased synthesis of the vasoconstrictor peptide endothelin 1 (encoded by EDN1) might be responsible for high blood pressure. The present study further confirmed the abnormal EDN1 upregulation within adipose tissue-derived stromal cells (ADSCs) derived from morbidly obese subjects. The overexpression of EDN1 in ADSCs derived from non-obese subjects significantly promoted the proliferation and migration of HUVECs and tube formation by human umbilical vein endothelial cell (HUVEC). Transcription factor NR4A3 was positively correlated with EDN1, binding to EDN1 promoter region to upregulate EDN1 expression. Similarly, the overexpression of NR4A3 in ADSCs derived from non-obese subjects significantly promoted the proliferation and migration of HUVECs and tube formation by HUVECs, as well as EDN1 protein levels in ADSCs. However, the effects of NR4A3 overexpression on EDN1 protein levels in ADSCs and the proliferation and migration of HUVECs and tube formation by HUVECs were significantly reversed by EDN1 silencing in ADSCs. In conclusion, NR4A3 is abnormally upregulated in ADSCs derived from morbidly obese subjects; NR4A3 could promote HUVEC angiogenesis through binding to EDN1 promoter and upregulating EDN1 expression.

To improve interfacial adhesion between wood veneer and high-density polyethylene (HDPE) film, wood veneer was thermally modified in an oven or chemically modified by vinyltrimethoxysilane. The wood veneers were used to prepare plastic-bonded wood composites (PBWC) in a flat-press process using HDPE films as adhesives. The results showed that both modifications reduced veneer hydrophilicity and led to enhancement in shear strength, wood failure, and water resistance of the resulting PBWC. The thermal treatment significantly decreased the storage modulus close to 130 °C (the melting temperature of plastic). Thermal-treated wood veneer maintains mechanical interlocking for bonding and veneer strength which then declined under thermal treatment due to hemicellulose degradation and cellulose de-polymerization. In the silane-treated PBWC, enhanced interlocking and a stronger bonding structure resulted from the reaction between the silane-treated veneer and HDPE. This strong bonding structure allowed thermal stability improvement demonstrated by high modulus and low tanδ values. However, the strength of silane-treated PBWC was still much lower than thermosetting resin-bonded composites at higher temperatures due to the melting behavior of thermoplastic polymer, precluding its use in certain applications.

Covalent organic frameworks (COFs) made their debut in 2005 and caused enthusiastic attention because of their ordered, crystalline structure. They are constructed with pure organic building blocks that are linked together by robust covalent linkages. COFs are applied in numerous fields due to their large surface area, architecture and chemistry stabilities, functional pore walls, and tunable frameworks. Incorporating COFs with chiral compounds can build chiral COFs (CCOFs), which have exhibited significant advantages in the chiral chemistry field. This review focuses on the applications of COFs for chiral catalysis, chiral separation, and chiral sensoring up to now. Furthermore, the synthesis and design strategies of CCOFs are also discussed in this article, since the COFs used in chiral chemistry are generally CCOFs. There also sums up the benefits and defects of COFs used in the chiral field and outlines future opportunities. The studies described in this review demonstrate not only the advantages of COFs in practical use but also novel solutions for the problems in the chirality area.

Broadband gap semiconductor silicon carbide (SiC) is regarded as a promising microwave absorber depending on its peculiar electrical and physicochemical characteristics. Herein, to explore a lightweight SiC-based microwave absorber with practical application potential as well as strong attenuation and broadband, SiC@SiO2 nanoparticles (SiC@SiO2 NPs) were successfully fabricated by a catalyst-free pyrolysis strategy using polycarbosilane (PCS) as precursor. According to systematic investigation results concerning the electromagnetic parameters, a reasonable synergistic mechanism integrated multiple reflections, Debye relaxation and interfacial polarization relaxation was proposed to demonstrate the superior microwave absorption performances of SiC@SiO2 NPs. The microwave absorption investigation exhibits that the corresponding minimal reflection loss (RL) of −45.53 dB with broad effective absorption bandwidth (EAB) of 5.52 GHz (12.48–18.0 GHz) almost covering the whole Ku-band can be achieved at the matching thickness of 1.85 mm, suggesting their superior dissipation capability.

Organic pyridinium ylide sensitizers NO108-NO111 with different anchoring groups show attractive applications in dye-sensitized solar cells. To elucidate the intrinsic sensitization mechanism of this series of dyes, theoretical calculations of electrochemical and spectroscopic properties for free and adsorbed ylides have been performed. Moreover, to prescreen and optimize suitable candidates for pyridinium ylide cells, the benzothiadiazole (BTD) group is introduced in the best-performing ylide NO111, and the afforded dye is coded as NO111-1. Comparing pyiridine-N-oxide in NO108, diethylmalonate in NO111 shows superior properties in terms of interfacial charge transfer, anti-aggregation, and long-term stability. It also demonstrates that the novel designed NO111-1-sensitized film possesses higher average theoretical maximum limit of short-circuit photocurrent density ( J SC max ≈ 23 mA/cm2), and slower parasitic recombination than NO111 one. This result is expected to further reveal the effects of anchoring groups on properties of dyes, and is helpful for the design of more efficient pyridinium ylide dyes.

Context Velvet antlers (VA) are claimed to have the effects on osteoporosis in traditional Chinese medicine. Aims So as to scientifically confirm this claim, a VA-based compound (VAC, the mixture of upper part of VA, deer blood, and calcined oyster shell powder in a ratio of 4:1:1) was produced and administered to osteoporotic model rats, with osteoporosis being induced by retinoic acid via gavage. Methods In total, 48 rats were used and divided into six groups (8/group). Concentrations of alkaline phosphatase and osteocalcin in the rat serum were measured, and bone ash weight, concentrations of calcium and phosphorus in rat femur were measured. Bone biomechanical test was performed using a computer-controlled three-point bending tester. Ratio of trabecular bone area to tissue area in a given view field of the femoral tissue section was histologically examined and calculated. Bone histomorphometry was measured using micro-CT. Key results No significant difference was found between the VAC-treated groups and the positive control (alendronate sodium) on the basis of the following tested parameters: (1) levels of alkaline phosphatase and osteocalcin in rat serum; (2) maximum load value (N) of femur and maximum compression force of lumbar vertebra; (3) concentrations of calcium and phosphorus in femur; (4) ratio of trabecular bone area to tissue area; and (5) bone histomorphometry. Conclusions Effects of VAC used in the present study on osteoporosis in the model rats were comparable to the alendronate sodium (western medicine for treating osteoporosis) on the basis of our selected parameters. Implications This compound has the potential to be developed as an effective traditional Chinese medicine for clinic use to treat osteoporosis.

A highly sensitive nitrite (NO2&minus, ) electrochemical sensor is fabricated using glassy carbon electrode modified with Au nanoparticle and grapheme oxide. Briefly, this electrochemical sensor was prepared by drop-coating graphene oxide-chitosan mixed film on the surface of the electrode and then electrodepositing a layer of Au nanoparticle using cyclic voltammetry. The electrochemical behavior of NO2&minus, on the sensor was investigated by cyclic voltammetry and amperometric i-t curve. The results showed that the sensor exhibited better electrocatalytic activity for NO2&minus, in 0.1 mol/L phosphate buffer solution (PBS) (pH 5.0). The oxidation peak current was positively correlated with NO2&minus, concentration in the ranges of 0.9 &micro, M to 18.9 &micro, M. The detection limit was estimated to be 0.3 &micro, M. In addition, the interference of some common ions (e.g., NO3&minus, CO32&minus, SO42&minus, Cl&minus, Ca2+ and Mg2+) and oxidizable compound including sodium sulfite and ascorbic acid in the detection of nitrite was also studied. The results show that this sensor is more sensitive and selective to NO2&minus, Therefore, this electrochemical sensor provided an effective tool for the detection of NO2&minus

Jatropha curcas L. is a drought and salt-tolerant oil plant widely used for various purposes and has considerable potential as a diesel/kerosene substitute or extender. Understanding the molecular mechanisms underlie that the response to various biotic and abiotic stresses of this plant could be important to crop improvement efforts. Here, a new AP2/ERF-type transcription factor gene, named JcERF2, was isolated from the leaves of J. curcas. Sequence analysis showed that the JcERF2 gene contains a 759-bp open reading frame encoding a polypeptide of 252 amino acids. The predicted JcERF2 protein contained a conserved DNA-binding domain (the AP2/ERF domain) with 58 amino acids. The JcERF2 protein is highly homologous with other ERFs. JcERF2 was localized in the nucleus by analysis with a JcERF2-green fluorescent protein (GFP) fusion protein. Quantitative polymerase chain reaction (qPCR) analysis showed that JcERF2 was induced by drought, salt, abscisic acid, and ethylene. Overexpression of JcERF2 in transgenic tobacco plants enhanced the expression of biotic and abiotic stress-related genes, increased the accumulation of free proline and soluble carbohydrates, and conferred tolerance to drought and salt stresses compared to the wild type (WT). Taken together, the JcERF2 gene is a novel AP2/ERF transcription factor involved in plant response to environmental factors, which can be used as a potential candidate gene for genetic engineering of crops.

Phosphomannose isomerase (PMI) is an enzyme that catalyses the first step of the L-galactose pathway for ascorbic acid (AsA) biosynthesis in plants. To clarify the physiological roles of PMI in AsA biosynthesis, the cDNA sequence of PMI was cloned from non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) and overexpressed in tobacco transformed with Agrobacterium tumefaciens. The AsA and soluble sugar contents were lower in 35S::BcPMI2 tobacco than in wild-type tobacco. However, the AsA level in BcPMI2-overexpressing plants under stress was significantly increased. The T1 seed germination rate of transgenic plants was higher than that of wild-type plants under NaCl or H2O2 treatment. Meanwhile, transgenic plants showed higher tolerance than wild-type plants. This finding implied that BcPMI2 overexpression improved AsA biosynthetic capability and accumulation, and evidently enhanced tolerance to oxidative and salt stress, although the AsA level was lower in transgenic tobacco than in wild-type tobacco under normal condition.

This study investigated the influence of heat treatment on the dimensional stability and mechanical properties of untreated and low molecular weight melamine–urea–formaldehyde (MUF) resin treated Eucalyptus pellita wood. Wood samples were heat treated under vacuum atmosphere in laboratory conditions at temperatures between 160 and 240 °C for 2–10 h. The results showed that anti-shrink efficiency and anti-swelling efficiency of MUF resin-impregnated heat-treated eucalypt wood were improved by up to 47 and 49 % at 240 °C for 10 h separately, which were greater than those of heat-treated wood. In relation to mechanical properties, the modulus of elasticity and modulus of rupture decreased with increasing temperature and time, but the reduction of properties appeared to be smaller for MUF resin-impregnated heat-treated wood. Therefore, heat treatment combined with resin treatment of eucalypt wood shows potential to improve the wood quality of solid wood products.

As a common organic pollutant in industrial and agricultural wastewater, p-Nitrophenol (p-NP) is difficult to be degraded naturally. Though, various methods have been developed for degradation of p-NP, the utilization of catalysts to electrochemically degrade p-NP became a novel effective way. In this article, two magnetic nanoparticles (carbon-encapsulated iron, Fe/C; carbon-encapsulated cobalt, Co/C) were prepared. Through a series of physical phase characterization, we found that the average dimension of the prepared magnetic nanoparticles arrived at 60 nm for Fe/C and 80 nm for Co/C, and within such small dimensions, the prepared nanoparticles might have some remarkable catalytic characters in electrochemical degradation of p-NP. Therefore, two novel types of Fe/C and Co/C modified glassy carbon electrodes were fabricated to investigate their catalytic activity for p-NP degradation. In our results, both of the two modified electrodes showed favorable stability and excellent electro-catalytic activity for p-NP degradation. In addition, two modified electrodes also exhibited favorable electro-catalytic reductive ability for p-NP. The electrochemical reactions on the surface of the two modified electrodes were all diffusion controlled processes. Therefore, Fe/C and Co/C were excellent bifunctional catalysts which could be considered as a practical way to be applied in industrial hydrogenation and oxidative degradation of organic compounds.

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

Cu/Cu2O nanowires were synthesized using anodic aluminum oxide templates in an aqueous acidic electrolyte using alternating current electrochemical deposition. The features of the final product were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (SEM). The results indicated that the diameter of the nanowires is about 50 nm, which is in accord with the size of the pores in the anodic aluminum oxide templates. The crystalline structure of the Cu and Cu2O nanowires exhibit preferred orientations of Cu (111) and Cu2O (200), respectively. The experimental results showed that contents of Cu and Cu2O in the final product are controlled by changing the pH value of the electrolyte. Pure Cu nanowires were obtained at lower pH values of 1–3, while pure Cu2O nanowires formed at a higher pH value of 5. When the pH = 4, the nanowires produced were a composite of Cu and Cu2O. The growth of Cu2O nanowires in acidic electrolyte is ascribed to a local increase in pH at the base of the pores in the template and a phenomenological model for this process is proposed and discussed.

A series of tests (lethal, sublethal, and behavioral) on earthworms were conducted as an eco-assessment of pesticides. In this study, the toxicity of cypermethrin-contaminating soil on adult and juvenile earthworms was assessed. Beside the acute and chronic tests, an avoidance response test was carried out. It was shown that the all-round toxicity from cypermethrin was weak on adult earthworms. Compared with adult earthworms, the toxicity of juvenile earthworms from cypermethrin especially chronic toxicity increased significantly. Growth and reproduction of earthworms appeared to be more severely affected by cypermethrin at juvenile stage than at adult stage. Applied at 10 mg/kg, cypermethrin had obvious adverse impact on the growth of juvenile earthworms, while 20 mg/kg, cypermethrin caused significant toxic effects in reproduction. The results also indicated that ecotoxicological risk assessment using only adult specimens may underestimate the effects of cypermethrin on soil invertebrate populations.

Ultrathin crystalline silicon (c-Si) solar cells, which are of several micrometers thick, have attracted much attention in recent years, since it can greatly save raw materials than the traditional ones. To enhance the absorption, as well as to improve the cell efficiency, of the ultrathin c-Si, light trapping nanostructures are used to increase the effective absorption length to close to the 4n 2 of the materials thickness, which is determined by the Lambertian limit. Here, we propose a novel interlaced semi-ellipsoid nanostructures (ISENs) to improve the performance of ultrathin c-Si solar cells. In this structure, the large and small periods in x and y direction can improve the light trapping capability at long and short wavelengths respectively. Meanwhile, the graded refractive index of the surface can act as the antireflection coating. By optimizing the ISENs, the short circuit current density of 30.15mA/cm 2 was achieved by simulations for a 2 μm thick c-Si solar cell with r x = 500 nm, r y = 200 nm, r z = 550 nm and without antireflection coating and metal back reflector. The absorption is close to 87% of the Lambertian limit with equivalent thickness. We expect this structure can be fabricated by low cost nanosphere lithography technology and used to improve the efficiency of the ultrathin c-Si solar cells.

The JcERF1 gene, which is related to the ERF family (ethylene responsive factor coding genes), was isolated and characterized from the oil tree Jatropha curcas. The JcERF1 protein contains conserved an AP2/EREBP DNA-binding domain of 58 amino acid residues. The JcERF1 gene could be induced by abscisic acid, high salinity, hormones, and osmotic stress, suggesting that JcERF1 is regulated by certain components of the stress-signaling pathway. The full-length and C-terminus of JcERF1 driven by the GAL4 promoter functioned effectively as a transactivator in yeast, while its N-terminus was completely inactive. Transient expression analysis using a JcERF1-mGFP fusion gene in onion epidermal cells revealed that the JcERF1 protein is targeted to the nucleus. Transgenic tobacco plants carrying CaMV35S::JcERF1 fragments were shown to be much more salt tolerant compared to wild-type plants. Our results indicate that JcERF1 is a new member of the ERF transcription factors family that may play an important role in tolerance to environmental stress.

A new fluorescent chemosensor based on an open-chain azacrown bearing a quinoline subunit was conveniently synthesized, which showed a remarkable enhanced fluorescent intensity in the presence of Cu2+ ion and a high selectivity toward Cu2+ ion over a wide range of tested metal ions in acetonitrile.

Coral-like mesoporous SnO2 was synthesized by controlled hydrolysis of SnCl4 and subsequent removal of the template by calcination in air. The obtained powder was doped directly with palladium chloride solution. The morphology, crystal structure, specific surface area, and photoelectrical and ethanol gas-sensing properties of undoped and Pd-doped coral-like SnO2 were investigated. The average crystalline sizes of undoped and Pd-doped SnO2 were estimated by Williamson–Hall plots to be 10.3 and 10.0 nm, respectively. From the N2 adsorption–desorption analysis, the pure sample had a surface area 63.3 m2/g with pore size distribution narrowly centered around 5.7 nm. The film sensors based on undoped and Pd-doped SnO2 exhibited novel photoelectrical properties. The photocurrents of the sensors decreased with increasing UV light intensity. The response of the Pd-doped SnO2 sensor to 500 ppm ethanol was 35.3 under UV illumination at room temperature. The results demonstrated that Pd doping could achieve room-temperature detection to ethanol under UV light radiation.

Two-dimensional nonlinear photonic crystals of lithium niobate with square lattices were fabricated. In these crystals, efficient quasiphase-matched second-harmonic generation was demonstrated by using second-order quasiphase matching. As a mode-locked Nd:yttritium–aluminum–garnet laser at 1064 nm with 35 ps pulse was used, we obtained an average power of 0.86 mW at 532 nm with 2.73 mW input, which corresponds to 42% internal conversion efficiency. The variations of second-harmonic output with crystal temperature and incident angle were measured. In addition, the relation between the second-harmonic output and reversed duty cycle was studied. All the experimental results are well consistent with simulations.

Toxicities were assessed for a pyrethroid (cypermethrin) and an organophosphate insecticide (chlorpyrifos) individually and in combination. A series of tests were conducted on different responses (acute, chronic, behavioral) of earthworms of species Eisenia fetida andrei in the ecological risk assessment of these pesticides. The results showed that the toxicity of the mixture of cypermethrin and chlorpyrifos was significantly higher than either of these pesticides individually, especially on the earthworm's chronic responses. At a concentration of 5 mg/kg, the mixture caused significant reductions on the growth and reproduction rates of earthworms, but did not cause any significant effect when the individual was tested. The increase in toxicity of the pesticide mixture means that the use of toxicity data obtained exclusively from single-pesticide experiments may underestimate the ecological risk of pesticides that actually present in the field.

A new fluorescent chemosensor (I) based on an open-chain azacrown bearing a quinoline moiety is synthesized in a four-step procedure starting from 2-nitrophenol.

In recent years, research interests in copper nanoparticles have been increased significantly due to their excellent performance in tribology, catalysis and many other fields. Howe ver, their applications have been still limited because the bare nanoparticles are easily oxidized. Ther efore, the study of copper nanoparticles encapsul ated in carbonaceous shells is an important issue. In this study, the carbon encapsulated copper nanoparticles were prep ared using copper nitrate as the metal sources and using sucrose as the carbon sources, through reducing and annealing. The phase, morphology, particle size and structure of as-prepared samples were charact erized using X-ray diffraction, field emission transmission electron microscopy, scanning electron mi croscopy and Raman spectroscopy, respec tively. The results indicate that the samples exhibit well core/shell structure, with sphere form and uniform size (50 nm in average). The copper cores consists of polycrystalline par ticles with fcc structure, whose size varies from 20 nm to 60 nm. The shell is amorphous carbon and its thickness is about 10 nm. In addition, the formation mechanism of carbon encapsulated copper nanoparticles was discussed and presented in the paper. Keywords: copper nanoparticles, core/shell, amorphous carbon, mechanism

The precursor hydrozincite was synthesized through hydrothermal reaction and hierarchically assembled 3D porous ZnO was prepared by calcination of the precursor at 400 °C for 15 min. The 3D porous ZnO was composed of micrometer spheres which were assembled from nanoflakes. The sensor based on 3D porous ZnO showed improved ethanol response compared to 2D porous ZnO nanoplates. The highest sensitivity of 77.5, 9.8 and 49.7, respectively, for the sensor based on 3D porous ZnO-2 were obtained for 100 ppm acetone, benzene and ethanol at the operation temperature of 420 °C, 420 °C and 340 °C, respectively. The sensor also show selectivity to acetone at the operation temperature of 420 °C. The highest sensitivity of the sensor based on ZnO-3 was of 59.9 to 100 ppm ethanol, the response increased linearly with the concentration of ethanol in the range of 10–1000 ppm. All the response and recovery times of the sensors were less than 20 s. The good sensing performance of the 3D porous ZnO sensor indicated that the hierarchically assembled 3D porous ZnO could be a promising candidate for highly sensitive gas sensors.

Ordered Ni/Al2O3 core–shell nanowire arrays were prepared in porous alumina membrane via alternating current electrodeposition and chemical etching methods. The shape of the inner Ni core is column...