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In this study, graphdiyne (GDY) was first reported as a substrate material for sodium-ion batteries (SIBs). The creative hybridization of GDY and molybdenum disulfide (MoS2) endows the composite with unique heterostructural and morphological advantages that boost the charge transport rate and enhance the battery discharge properties. Electrochemical results indicated that the MoS2@GDY anode displays a considerable discharge capacity of up to 328 mAh g-1 at 1000 mA g-1. A capacity retention of 93% even at testing current back to 200 mA g-1 suggests superior rate characteristics. An outstanding stable cyclic performance of 217 mAh g-1 is obtained at a high testing density. The attractive results not only demonstrate that GDY could be used not only as an effective conductive substrate to prevent the host material from agglomerating in the electrochemical process but also provide a novel design for fabricating efficient electrode materials for future energy-storage systems.

Peripheral human nerves fail to regenerate across long tube implants (>2 cm), and tissue-engineered nerve grafts represent a promising treatment alternative. The present study aims to investigate the testosterone propionate (TP) repair effect of acellular nerve allograft (ANA) seeded with allogeneic bone marrow mesenchymal stem cells (BMSCs) on 3-cm canine sciatic nerve defect. ANA cellularized with allogeneic BMSCs was implanted to the defect, and TP was injected into the lateral crus of the defected leg. The normal group, the autograft group, the ANA + BMSCs group, the ANA group, and the nongrafted group were used as control. Five months postoperatively, dogs in the TP + ANA + BMSCs group were capable of load bearing, normal walking, and skipping, the autograft group and the ANA + BMSCs group demonstrated nearly the same despite a slight limp. The compound muscle action potentials (CMAPs) on the injured side to the uninjured site in the TP + ANA + BMSCs group were significantly higher than that in the ANA + BMSCs group [CMAPs ratio at A: F(3, 20) = 191.40; 0.02, CMAPs ratio at B: F(3, 20) = 43.27; 0.01]. Masson trichrome staining revealed that in the TP + ANA + BMSCs group, both the diameter ratio of the myelinated nerve and the thickness ratio of regenerated myelin sheath were significantly larger than that in the other groups [the diameter of myelinated nerve fibers: F(3, 56) = 13.45; P < .01, the thickness ratio of regenerated myelin sheath: F(3, 56) = 51.25; P < .01]. In conclusion, TP could significantly increase the repairing effects of the ANA + BMSCs group, and their combination was able to repair 3-cm canine sciatic nerve defect. It therefore represents a promising therapeutic approach.

Soil respiration (SR) is a major process of carbon loss from dryland soils, it is closely linked to precipitation which often arrived as discrete episodic event. However, knowledge about the dynamic patterns of SR of biologically crusted soils in response to precipitation pulses is still quite limited. In this study, we investigated CO 2 emission from moss (MCS) and cyanobacteria-lichen (CLCS) crusted soils after 2, 4, 8, 16, and 32 mm of precipitation treatments during the dry season in the Tengger Desert, northern China. Results showed that two hours after precipitation, SR rates of both MCS and CLCS were often increased up to 18 times greater than those before rewetting, and then gradually declined and returned to background levels, the decrease was faster at lower precipitation intensity and slower at the higher. The peak and average SR rates over the first 2 h in MCS increased with increasing precipitation magnitude, but did not vary in CLCS. Total CO 2 emission over the whole 72-h experiment ranged from 1.35 to 5.67 g C m −2 in MCS, and 1.11 to 3.19 g C m −2 in CLCS. Peak and average SR rates as well as total carbon loss were all greater in MCS than in CLCS. SR rates of both MCS and CLCS were logarithmically correlated with soil water content. Comparisons of SR among different amount of precipitation events together with the analysis of long-term precipitation data suggest that small rainfall events have the potential for large short-term carbon losses and biological soil crusts might be the major contributor to soil CO 2 emission of the water-limited desert ecosystem.

The present study proposed a novel and highly selective and sensitive method for Ag+ ion detection based on gold nanoparticles (AuNPs) anti-aggregation. Thiamazole can induce AuNPs aggregation due to electrostatic interactions, which result in color transitions in the AuNPs solution from red to blue. However, the presence of Ag+ ions results in the preferential combination of the pyridinic nitrogen of thiamazole with the Ag+ ions. In addition, the Ag+ ions oxidize the sulfhydryl groups(-SH), which inhibit AuNPs aggregation and prompt a color change from blue to red. As a result, the present study established a method for Ag+ ion determination by AuNPs-thiamazole colorimetric probe based on the aforementioned anti-aggregation mechanism. The probe dynamic range was easily tuned via adjustments of the thiamazole amount. The relationship between the Ag+ concentration and AuNPs aggregation was monitored by ultraviolet–visible light (UV–Vis) spectroscopy at a dynamic range of 0.1 nM–9 μM and at a detection limit of 0.042 nM. The river water and tap water recovery analysis validated the successful operation of this colorimetric sensor in environmental monitoring.

Based on the selective recognition of the polyethylene (PE) block of polyethylene-block-poly(ethylene glycol) (PE-b-PEG) by 1,4-diethoxypillar[5]arene (DEP5A), two novel thermo and competitive guest (1,4-dibromobutane or hexanedinitrile) responsive polypseudorotaxanes (PPRs) have been successfully constructed. The formation of PPRs both in solution and in the solid state was demonstrated by (1)H NMR, 2D NOESY, and WAXD analyses. TGA data illustrate that PPRs exhibit higher thermal stability than their precursor diblock copolymers. Moreover, intriguing porous disk-like aggregates are produced by electrospraying of PPRs in CHCl3 and the self-assembled structures of PPRs are totally changed by the addition of 1,4-dibromobutane or hexanedinitrile, demonstrating their competitive guest stimuli-responsiveness.

Background Trichophyton mentagrophytes is an important zoonotic dermatophytic (ringworm) pathogen; causing severe skin infection in humans and other animals worldwide. Fortunately, commonly used fungal skin disease prevention and treatment measures are relatively simple. However, T. mentagrophytes is primarily studied at the epidemiology and drug efficacy research levels, yet current study has been unable to meet the needs of clinical medicine. Zinc is a crucial trace element for the growth and reproduction of fungi and other microorganisms. The metal ions coordinate within a variety of proteins to form zinc finger proteins, which perform many vital biological functions. Zinc transport regulatory networks have not been resolved in T. mentagrophytes. The T. mentagrophytes transcriptome will allow us to discover new genes, particularly those genes involved in zinc uptake. Result We found T. mentagrophytes growth to be restricted by zinc deficiency; natural T. mentagrophytes growth requires zinc ions. T. Mentagrophytes must acquire zinc ions for growth and development. The transcriptome of T. mentagrophytes was sequenced by using Illumina HiSeq™ 2000 technology and the de novo assembly of the transcriptome was performed by using the Trinity method, and functional annotation was analyzed. We got 10,751 unigenes. The growth of T. mentagrophytes is severely inhibited and there were many genes showing significant up regulation and down regulation respectively in T. mentagrophytes when zinc deficiency. Zinc deficiency can affect the expression of multiple genes of T. mentagrophytes. The effect of the zinc deficiency could be recovered in the normal medium. And we finally found the zinc-responsive activating factor (ZafA) and speculated that 4 unigenes are zinc transporters. We knocked ZafA gene by ATMT transformation in T. mentagrophytes, the result showed that ZafA gene is very important for the growth and the generation of conidia in T. mentagrophytes. The expression of 4 zinc transporter genes is potentially regulated by the zinc-responsive activating factor. The data of this study is also sufficient to be used as a support to study T. mentagrophytes. Conclusion We reported the first large transcriptome study carried out in T. mentagrophytes where we have compared physiological and transcriptional responses to zinc deficiency, and analyzed the expression of genes involved in zinc uptake. The study also produced high-resolution digital profiles of global genes expression relating to T. mentagrophytes growth. Electronic supplementary material The online version of this article (10.1186/s12864-017-4284-3) contains supplementary material, which is available to authorized users.

Hydrophilic, fluorescent hybrid nanoprobes (NDI@HNPs) encapsulated with the hydrophobic pH-responsive fluorophore (N,N'-di-n-dodecyl-2,6-di(4-methyl-piperazin-1-yl)naphthalene-1,4,5,8-tetracarboxylic acid diimide, NDI) for recognizing and mapping the route of cell phagocytosis have been fabricated based on the self-assembly of amphiphilic diblock copolymer PS-b-PAA and the subsequent shell cross-linking with 3-mercaptopropyltrimethoxy silane (MPTMS). The as-synthesized NDI@HNPs has a typical spherical morphology of 46 nm in diameter with excellent monodispersity in aqueous solution. The NDI@HNPs probe exhibits extremely low cytotoxicity, fast real time pH response and enhanced fluorescence intensity under acidic environment with respect to the corresponding free dye in highly polar aqueous system because of the encapsulation of NDI molecules inside nanoparticle cores with weak polarity environment. The fluorescence intensity of NDI@HNPs is enhanced by 55-fold upon changing from neutral (pH = 7.4) or basic (pH = 8.4) to acid (pH = 3.4) in aqueous system, in contrast to the serious fluorescence quenching of free NDI in the same medium, which can exactly meet the physiological pH range in cells. The favorably long emission wavelength is beneficial to the low scattering and minimal interfering requirements to fluorescent bioimaging. Moreover, functionalization with rapid cell-penetrating peptides (HIV-1 TAT) allows them to overcome the physiological and biological barriers during the phagocytosis process. Its characteristic fluorescent response to pH benefits the intracellular labeling and organelle targeting, realizing the real time tracking of the probe entry into cancer cells, the accumulation into the endolysosome and the further escape.

Thermoreversible crosslinking supramolecular polymers with weak hydrogen bonds were prepared from fatty dimer acids, diamines and sulfonyl isocyanate. The oligomers as backbones of supramolecular polymers have low molecular weights (5–7 repeating units). The hydrogen-bonding networks behave like elastic polymers with high rubber plateaus at high storage modulus, and have low melting temperature that is favoring the low temperature processing. The addition of sulfonyl isocyanate introduces the sulfonyl urethane groups (−O-CO-NH-SO2) that increase the diversity of self-complementary hydrogen bonds. However, the large bulk of sulfonyl groups (O = S = O) prolongs the distance of hydrogen bonds. The supromolecuar polymer with small chemical network sites has higher tensile length and Tm between the supromolecular polymers with sulfonyl groups.

A pre-column derivatization method for the simple, sensitive determination of biogenic amines using 10-ethyl-acridine-3-sulfonyl chloride (EASC) as labeling reagent with fluorescence detection and mass spectrometry (MS) identification has been developed. After pre-column derivatization, the labeled biogenic amines were separated on a Hypersil BDS-C18 column by gradient elution. The derivatives showed an intense protonated molecular ion corresponding m/z [M + H]+ in positive-ion mode. The collision-induced dissociation of protonated molecular ion formed specific fragment ions at m/z 196.5, m/z 222.7, m/z 224.4 and m/z 272.5, m/z 286.2. Satisfactory linear responses were observed at the concentration range of 0.02–10 μmol L−1 with coefficients of >0.9993. Detection limits obtained by the analysis of a derivatized standard containing 0.2 pmol of each biogenic amine, were from 20.22 to 109.2 fmol (at a signal-to-noise ratio of 3). The relative standard deviations of retention times and peak areas for each biogenic amine were

1. This study examined expression of two primary transmembrane Ca 2+ export proteins (plasma membrane Ca 2+ ATPase, (PMCA); Na + /Ca 2+ exchanger, sodium/calcium exchanger (NCX)) in epithelial (antennal gland, kidney) and non-epithelial (axial abdominal muscle) tissues of the freshwater crayfish Procambarus clarkii following exposure (28 days) to 4 °C (compared with control 23 °C). 2. Crayfish tissues responded to cold exposure within 5–7 days by upregulating the mRNA (determined through real-time polymerase chain reaction (PCR)) for both PMCA and NCX. After 28 days, levels were 4–5× higher in antennal gland and 2–3× higher in muscle. In situ hybridization localized the mRNA increase to the nephridial canal in antennal gland sections and to the extensor muscles in the tail. Western blotting confirmed corresponding increases in PMCA protein expression; however, expression of NCX protein was unchanged.

Basolateral Na + /Ca 2+ exchanger (NCX) and plasma membrane Ca 2+ ATPase (PMCA) are the primary transmembrane proteins that export calcium (Ca 2+ ) from cells. In our lab we use a nonmammalian animal model, the freshwater crayfish, to study cellular Ca 2+ regulation. Two experimental conditions are employed to effect Ca 2+ dyshomeostasis: (a) in the postmolt stage of the crustacean molting cycle increased unidirectional Ca 2+ influx associated with cuticular mineralization is accompanied by elevated basolateral Ca 2+ export (compared with intermolt Ca balance); and (h) exposure of the poikilothermic crayfish to cold acclimation (4°C) causes influx of Ca 2+ into cells, which is compensated by increased basolateral Ca 2+ export (compared with exposure to 23°C). This study compares expression of both NCX and PMCA mRNA (real-time PCR) and protein (Western) in both epithelial (kidney) and nonepithelial tissue (tail muscle) during elevated basolateral Ca 2+ export. Both experimental treatments produced increases in NCX and PMCA expression (mRNA and protein) in both tissues. Mineralization produced greater upregulation of mRNA in kidney than in tail, whereas cold acclimation yielded comparable increases in both tissues. Protein expression patterns were generally confirmatory of real-time PCR data although expression changes were less pronounced. Both experimental treatments appear to increase basolateral Ca 2+ export.

SUMMARYThis study describes the cloning, sequencing and functional characterization of an epithelial Ca2+ channel (ECaC)-like gene isolated from antennal gland (kidney) of the freshwater crayfish Procambarus clarkii. The full-length cDNA consisted of 2687 bp with an open reading frame of 2169 bp encoding a protein of 722 amino acids with a predicted molecular mass of 81.7 kDa. Crayfish ECaC had 76–78% identity at the mRNA level (80–82% amino acid identity) with published fish sequences and 56–62% identity at the mRNA level (52–60% amino acid identity) with mammalian ECaCs. Secondary structure of the crayfish ECaC closely resembled that of cloned ECaCs. Postmolt ECaC expression was exclusively restricted to epithelia associated with Ca2+ influx and was virtually undetectable in non-epithelial tissues (eggs, muscle). Compared with expression levels in hepatopancreas, expression in gill was 10-fold greater and expression was highest in antennal gland (15-fold greater than in hepatopancreas). Compared with baseline expression levels in intermolt stage,expression of ECaC in antennal gland increased 7.4- and 23.8-fold,respectively, in pre- and postmolt stages of the molting cycle. This increase was localized primarily in the labyrinth and nephridial canal, regions of the antennal gland associated with renal Ca2+ reabsorption. The ECaC in crayfish appears to be expressed in epithelia associated with unidirectional Ca2+ influx and relative expression is correlated with rate of Ca2+ influx.

NCX (sodium/calcium exchanger) is a bidirectional Ca2+ transporter that plays a critical role in Ca2+ homeostasis. The present study employed real-time PCR and in-situ hybridization techniques to c...

Exposure to elevated external Ca2+ resulted in upregulation of PMCA3 and NCX in both gill and kidney; however, expression in liver remained unchanged. Gill and kidney appear to respond to elevated apical Ca2+ entry with increased basolateral efflux. The liver may be pre-adapted to handle Ca2+ load in the diet and, as such, does not need to increased expression of basolateral export mechanisms when environmental levels are elevated. We will further explore these trends through protein analysis.

ECaC is upregulated in pre- and postmolt stage (compared with intermolt) associated with elevated renal Ca2+ (re)absorption. Basolateral PMCA3 expression exhibited a similar profile in other studies. Collectively these results indicate that the expression of genes controlling Ca entry (apical, ECaC) and exit (basolateral, PMCA) from epithelial cells are closely coordinated. ECaC was more abundant in epithelial tissues that effect Ca2+ translocation (gill, kidney) than in non-epithelial tissues.

Northern blot analysis indicated that the level of PMCA3 mRNA expression in all tissues increased significantly in pre/postmolt stages as compared to a very low level in the intermolt stage. Similar expression patterns were confirmed at the protein level by Western blotting. In situ hybridization confirmed that PMCA3 expression is increased in pre- and postmolt in kidney. Collectively these results indicate that the crayfish PMCA3 plays a crucial role in maintaining Ca2+ homeostasis during the fluctuations in Ca2+ flux associated with the crayfish molting cycle.

The molting cycle of the freshwater crayfish Procambarus clarkii has emerged as an ideal model to study cellular/molecular mechanisms of Ca homeostasis because of its ability to maximally absorb Ca from a Ca deficient environment. Freshwater contains only 1 mM Ca as opposed to the 10 mM Ca afforded by marine environments. The model is based on a negligible net transepithelial Ca flux during intermolt that changes to vectorial Ca flux around ecdysis. During premolt, 20% of cuticular Ca is reabsorbed for deposition into CaCO3 disks and the remainder is excreted. Postmolt is characterized by net environmental Ca uptake rates of 2-10 mmol/kg/h and remobilization of stored Ca. Both sources are subsequently used for the calcification of a new exoskeleton. The Ca transporting epithelia are the gills, antennal gland (kidney), hepatopancreas (liver) and cuticular hypodermis. Arthropod molting is coordinated by the steroid ecdysone and unknown environmental cues. Previous studies have shown a marked increase in basolateral Ca pump expression during postmolt, suggesting that Ca transporting proteins are upregulated during periods of elevated transepithelial Ca uptake. Kinetic studies suggest that the NCX is the primary extrusion mechanism for basolateral Ca efflux. Therefore, we propose that the NCX may be upregulated during premolt and postmolt compared with intermolt in hepatopancreas and antennal gland.

As a standard instrument to calibrate the radon monitors, radon chamber is in urgent need with the deepening study on Radon and its progeny. According to the requirement of calibrating the radon monitors and radon detectors, the multifunctional and automatic controlled radon chamber is designed and constructed. By the reason of radon decay, the radon concentration in the chamber is continuously changing. The radon concentration must keep stability and homogeneity in order to calibrate the radon monitors and bio-culture. The supply and control of radon in the chamber is a critical problem in the design of Radon chamber. The paper introduced the mathematic model of dynamic radon replenishment according to the law of radon decay, three time parameters to replenish radon is discussed. The related automatic monitor and control system is developed by this mathematic model, the expected radon concentration can keep stability and homogeneity controlled by the system. The structure of radon chamber and the design flow system is presented in detail. The main performance parameter of the radon chamber such as airproof, stability and radon concentration certification is discussed. The research result can be used to calibrate the radon monitors, biological test on radiation environment and radiation medicine test.

The availability of ambient calcium is vastly different in fresh water versus salt water. This leads to the evolution of different calcium conservation strategies in freshwater crustaceans versus t...

SUMMARY This paper describes the cloning and functional characterization of the heart muscle isoform of Sarco/endoplasmic reticulum Ca2+-ATPase(SERCA) from crayfish Procambarus clarkii. The complete crayfish heart SERCA, identified by reverse transcription-polymerase chain reaction(RT-PCR) and rapid amplification of cDNA ends (RACE), consists of 4495 bp with a 3060 bp open reading frame, coding for 1020 amino acids. This isoform differs from the previously identified axial abdominal (tail) muscle SERCA solely in its C-terminal amino acids. The last nine amino acids of the tail muscle isoform are replaced by 27 hydrophobic amino acids in the heart isoform that have the potential to form an additional transmembrane domain. Consistent with other invertebrate studies, Southern blot analysis suggested that the heart and tail muscle isoforms are encoded from the same gene that is equally related to SERCA-1, -2 and -3 of vertebrates. The tissue distributions of these two isoforms have been assessed using isoform-specific probes and northern analysis. A cardiac-specific probe bound only to a 5.8 kb species in heart and had minimal cross-hybridization with 7.6 and 5.8 kb species in eggs and no hybridization with tail muscle. A tail-isoform-specific probe hybridized with a 4.5 kb species in tail muscle and cross-hybridized with a 4.5 kb species in eggs and 8.8 kb in heart muscle. Both isoforms are expressed in eggs suggesting that transcripts are formed early in development and are subsequently broadly expressed in all tissue types. Expression of the cardiac muscle SERCA isoform varied with the stage of moulting. Expression was high in intermoult and decreased in premoult. However, expression was restored rapidly in postmoult (within 2 days) unlike expression of tail muscle SERCA,which remained downregulated for weeks. Differences in contractility between the two muscle types in the postmoult period may explain these expression patterns.