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In the process of epithelial-mesenchymal transition (EMT), epithelial cancer cells transdifferentiate into mesenchymal-like cells with high motility and aggressiveness, resulting in the spread of tumor cells. Immune cells and inflammation in the tumor microenvironment are the driving factors of EMT, but few studies have explored the core targets of the interaction between EMT and tumor immune cells. We analyzed thousands of cases of gastric cancer and gastric tissue specimens of TCGA, CPTAC, GTEx and analyzing QPCR and IHC data of 56 gastric cancer patients in SYSU Gastric Cancer Research Center. It was known that EMT has an important connection with the infiltration of NK cells, and that the expression of vinculin may be the target of the phenomenon. The increased expression of vinculin is closely related to the aggressiveness and distant metastasis of cancer, which affects the survival prognosis of the patient. Moreover, through in vitro experiments under 3D conditions, we found that vinculin, cell invasion and metastasis are clearly linked. VCL can affect EMT and tumor immunity by regulating EPCAM gene expression. The role and mechanism of action of vinculin have been controversial, but this molecule may downregulate EpCAM (epithelial cellular adhesion molecule) and its own role in gastric cancer through DNA methylation, causing NK cells to enrich into tumor cells and kill tumor cells. At the same time, it promotes the occurrence of EMT, which in turn causes tumor metastasis and thus poorer prognosis.

Chemotherapy plays an irreplaceable role in the treatment of GC, but currently available chemotherapeutic drugs are not ideal. The application of medicinal plants is an important direction for new drug discovery. Through drug screening of GC organoids, we determined that ailanthone has an anticancer effect on GC cells in vitro and in vivo. We also found that AIL can induce DNA damage and apoptosis in GC cells. Further transcriptome sequencing of PDX tissue indicated that AIL inhibited the expression of XRCC1, which plays an important role in DNA damage repair, and the results were also confirmed by western blotting. In addition, we found that AIL inhibited the expression of P23 and that inhibition of P23 decreased the expression of XRCC1, indicating that AIL can regulate XRCC1 via P23. The results of coimmunoprecipitation showed that AIL can inhibit the binding of P23 and XRCC1 to HSP90. These findings indicate that AIL can induce DNA damage and apoptosis in GC cells. Meanwhile, AIL can decrease XRCC1 activity by downregulating P23 expression to inhibit DNA damage repair. The present study sheds light on the potential application of new drugs isolated from natural medicinal plants for GC therapy.

Flexible sensors based on conductive hydrogels have been of wide interest in the field of smart wearable electronics due to the excellent stretchability and strain-responsive ability. However, lacking harsh environment tolerance and self-recovery properties seriously limit their practical applications. Therefore, the development of anti-fatigue hydrogels with anti-freezing and water-retaining abilities is urgently required. In this study, we constructed a fully physically cross-linked gelatin/poly(N-hydroxyethyl acrylamide)/glycerin/lithium chloride double network (gelatin/pHEAA/Gly/LiCl DN) organohydrogel based on a hydrogen bond crosslinking strategy using a facial one-pot method. The dynamic hydrogen bond in the DN organohydrogels provided an effective energy dissipation pathway, which produced gels with high tensile strength/strain (2.14 MPa/1637.49%), fast self-recovery properties and strong interfacial toughness. The introduction of binary solvents of water and glycerin endowed the DN organohydrogels with excellent anti-freezing and water-retaining properties. Furthermore, a simple flexible sensor was fabricated based on the organohydrogel for detecting human motions. The sensor not only showed remarkable sensitivity (GF = 14.54), broad strain range (0–1600%) and high response speed (0.2 s), but also presented accurate and reliable signals under different mechanical deformations and low temperature (−20 °C). This work provides a feasible way to build high mechanical and sensing performance organohydrogel-based sensors with anti-freezing and water-retaining abilities, which greatly promotes the application of flexible sensors in the field of smart wearable electronic devices, electronic skin and human/machine interface.

SnTe is an emerging IV-VI metal chalcogenide, but its low Seebeck coefficient and high thermal conductivity mainly originating from the high hole concentration limit its thermoelectric performance. In this work, an amorphous carbon core-shell-coated PbTe nanostructure prepared by a "bottom-up" method is first incorporated into the Sn1-ySbyTe matrix to enhance the thermoelectric performance of SnTe. The square-like PbTe nanoparticles maintain their original cubic morphology and do not grow up obviously after the SPS process due to the coating of the C layer, bringing about the formation of nanopores locally, while Sb alloying induces Sb point defects and Sb-rich precipitates. All these unique hierarchical microstructures finally lead to an ultralow lattice thermal conductivity (∼0.48 W-1 m-1 K-1) approaching amorphous limits (∼0.40 W-1 m-1 K-1). In addition, the incorporation of PbTe@C core-shell nanostructures decreases the carrier mobility obviously with a slight loss in carrier concentration, resulting in the deterioration of electrical properties to a certain extent. As a result, a peak thermoelectric figure of merit (ZT) of 1.07 is achieved for Sn0.89Sb0.11Te-5%PbTe@C at 873 K, which is approximately 154.76% higher than that of pristine SnTe. This work provides a new strategy to enhance the thermoelectric performance of SnTe and also offers a new insight into other related thermoelectric systems.

Boron nitride nanosheets (BNNSs) are widely used as fillers to increase the thermal conductivity of a substrate. However, the solvent resistance of BNNSs limits their widespread application. In thi...

Gastric cancer (GC) is the third leading cause of cancer deaths worldwide. Conventional chemotherapy has been proven useful to only a portion of the patients. Previous developed targeted drugs are more effective and tolerable than conventional drugs. Thus the development of novel drugs targeting markers is an urgent task and the main direction for future research. Ethaselen, an inhibitor of thioredoxin reductase (TrxR), has been considered an important anticancer target drug. Previous studies show that it is effective on treating many kinds of cancers. In this paper, we examined that ethaselen effectively inhibited the growth of gastric cancer cells and promoted apoptosis. Organoids were cultured from patient-derived cells in a three-dimension form which are widely used in cancer research to help us understand cancer cells behavior at the sub-organ level and develop novel drugs. We established a drug testing and screening system using GC-derived organoids by recapitulating tumor microenvironment. We confirmed that the TrxR-targeting ethaselen could be a novel and effective drug for gastric cancer treatment.

Background Oxaliplatin is one of the most commonly used chemotherapeutic agent for the treatment of various cancers, including gastric cancer. It has, however, a narrow therapeutic index due to its toxicity and the occurrence of drug resistance. Hence, it is of great significance to develop novel therapies to potentiate the anti-tumor effect and reduce the toxicity of oxaliplatin. In our previous study, we demonstrated that ethaselen (BBSKE), an inhibitor of thioredoxin reductase, effectively inhibited the growth of gastric cancer cells and promoted apoptosis in vitro. In the present study, we investigated whether BBSKE can potentiate the anti-tumor effect of oxaliplatin in gastric cancer in vivo and vitro. Methods Cellular apoptosis and ROS levels were analyzed by flow cytometry. Thioredoxin reductase 1 (TrxR1) activity in gastric cancer cells, organoid and tumor tissues was determined by using the endpoint insulin reduction assay. Western blot was used to analyze the expressions of the indicated proteins. Nude mice xenograft models were used to test the effects of BBSKE and oxaliplatin combinations on gastric cancer cell growth in vivo. In addition, we also used the combined treatment of BBSKE and oxaliplatin in three cases of gastric cancer Patient-Derived organoid (GC-PDO) to detect the anti-tumor effect. Results We found that BBSKE significantly enhanced oxaliplatin-induced growth inhibition in gastric cancer cells by inhibiting TrxR1 activity. Because of the inhibition of TrxR1 activity, BBSKE synergized with oxaliplatin to enhance the production of ROS and activate p38 and JNK signaling pathways which eventually induced apoptosis of gastric cancer cells. In vivo, we also found that BBSKE synergized with oxaliplatin to suppress the gastric cancer tumor growth in xenograft nude mice model, accompanied by the reduced TrxR1 activity. Remarkably, we found that BBSKE attenuated body weight loss evoked by oxaliplatin treatment. We also used three cases of GC-PDO and found that the combined treatment of BBSKE and oxaliplatin dramatically inhibited the growth and viability of GC-PDO with increased ROS level, decreased TrxR1 activity and enhanced apoptosis. Conclusions This study elucidates the underlying mechanisms of synergistic effect of BBSKE and oxaliplatin, and suggests that the combined treatment has potential value in gastric cancer therapy.

The clinical success of the two BTK inhibitors, ibrutinib and acalabrutinib, represents a major breakthrough in the treatment of chronic lymphocytic leukemia (CLL) and has also revolutionized the treatment options for other B cell malignancies. Increasing evidence indicates that in addition to their direct effects on B lymphocytes, both BTK inhibitors also directly impact the homeostasis, phenotype and function of many other cell subsets of the immune system, which contribute to their high efficacy as well as adverse effects observed in CLL patients. In this review, we attempt to provide an overview on the overlapping and differential effects of ibrutinib and acalabrutinib on specific receptor signaling pathways in different immune cell subsets other than B cells, including T cells, NK cells, monocytes, macrophages, granulocytes, myeloid-derived suppressor cells, dendritic cells, osteoclasts, mast cells and platelets. The shared and distinct effects of ibrutinib versus acalabrutinib are mediated through BTK-dependent and BTK-independent mechanisms, respectively. Such immunomodulatory effects of the two drugs have fueled myriad explorations of their repurposing opportunities for the treatment of a wide variety of other human diseases involving immune dysregulation.

Background: Chemotherapy plays an irreplaceable role in the treatment of gastric cancer (GC), but currently available chemotherapeutic drugs are not ideal. Medicinal plants are an important direction for new drug discovery. Methods: We combined literature collection, organoid drug screening and PDX verification to search for new, effective drugs. The effect of AIL on the GC cells was investigated by CCK-8 assays, Colony Formation Assay and Cell Viability, Cell migration and invasion assay and PDX mice model. The expression of indicated RNA and proteins were measured by qRT-PCR ,IHC and western blotting. The proteins HSP90 binding to P23 or XRCC1 were identified by Co-IP. Results: Through drug screening of GC organoids, we had determined that ailanthone (AIL) has an anticancer effect on GC cells in vitro and in vivo. We also found that AIL promoted apoptosis of GC cells through flow cytometry analysis and the expression of caspase 3 and H2AX were significantly enhanced by AIL in GC cells and tumor tissues, suggesting that AIL can induce DNA damage and apoptosis of GC cells. Further transcriptome sequencing of the PDX tissue indicated that AIL inhibited the expression of XRCC1 which plays an important role in DNA damage repair, and the results were also confirmed by western blotting. In addition, we found that AIL inhibited the expression of P23 and inhibition of P23 decreased the expression of XRCC1 through western blotting analysis, indicating that AIL can regulate XRCC1 via P23. The results of co-immunoprecipitation showed that AIL can inhibit the binding of P23 and XRCC1 to HSP90 respectively.Conclusion: These findings indicate that AIL can induce DNA damage and apoptosis of GC cells. Meanwhile, AIL can decrease XRCC1 by downregulating P23 to inhibit DNA damage repair. The present study shed light to the new drug isolated from natural medicinal plants for GC therapy.

Several advances in nanomedicine have been accompanied by rising concerns about the bioaccumulation and toxicity of gold nanoparticles (AuNPs). Here, we assessed the in vivo fate of diversely sized AuNPs that were injected into mice as a computed tomography contrast agent and examined with multi-scale analyses across the organ, tissue, cell, and subcellular levels. After focusing on the strong detected accumulation in livers, our data revealed a set of three clear, exposure-time-dependent patterns based on i) AuNPs deposit morphology and ii) readily identifiable phenotypes for AuNP-impacted subcellular vesicles. Importantly, we detected no obvious differences in liver function, liver cell apoptosis, or autophagy upon exposure to AuNPs. Thus, our study illustrates an accessible experimental and high-resolution data interpretation framework for quickly obtaining and contextualizing informative trends about any AuNP-triggered patterns of subcellular damage in nanomedicine studies; these can help guide cytotoxity and safety testing of diagnostic nanomedical technologies.

This paper presents the results regarding the prevention and control of gas hazards in a high-gas tunnel under construction. First, some effective methods were introduced, and the results of the gas pressure and gas content measured with and without the prevention methods were compared. Next, the gas emission amounts were predicted according to the measurements, and the required air volume for preventing a potential gas explosion hazard was determined. Finally, a computational study was carried out to investigate the effects of the transverse and longitudinal outlet locations of the ventilation duct on the gas movement in the tunnel. The results showed that with an increase in the longitudinal distance between the outlet and the heading face, the percentage of dead zones at the heading face of the upper bench increased, while the percentage of dead zones at the heading face of the lower bench observably decreased at first and then increased gradually. Additionally, the maximum methane concentration decreases initially and then increases. The percentages of dead zones were at relatively low levels when the outlet was located at the tunnel vault, whereas some relatively higher percentages of dead zones existed when the outlet was located at the tunnel spandrel or hance. The maximum methane concentration increased gradually when the location of the ventilation outlet moved away from the tunnel axis. In this case, the optimal outlet location for the ventilation duct was suggested to be 20 m away from the heading face of the upper bench and located near the tunnel vault.

Studies on the recovery of tungsten and molybdenum from refractory scheelite–powellite blend concentrates – mainly composed of scheelite, powellite, and fluorite – were performed using soda-silicon...

SnTe is considered as the appropriate substituent candidate of traditional PbTe due to the environmental-friendly nature. Herein, a series of Sn1–3xBi2xZnxTe (x = 0, 0.01, 0.02, 0.03) and Sn1–3xBi2xZnxTe-5%Cu2Te samples are fabricated, and their thermoelectric performances are studied. We first demonstrate that the solubility limit of the Zn in SnTe is less than 1% under the conventional melting process and the excess ZnTe precipitated in the matrix. Secondly, co-doping of Bi and Zn synergistically enhances electrical properties significantly over a wide temperature range due to Bi-doping-driven band convergence and Zn-doping-driven resonant level supported by computational calculations of DFT. Moreover, Zn-doping-induced precipitates with nano- to micro-meter size, Bi/Zn dual-point defect and Cu2Te-alloying-induced interstitial atoms can simultaneously block phonon transport in wide frequency range, resulting in an ultralow lattice thermal conductivity of ~0.51 W−1m−1K−1 at 873 K. Consequently, the synergistic regulation of electrical and thermal properties yields a peak ZT of ~ 1.3 at 873 K for Sn0.94Bi0.04Zn0.02Te- 5%Cu2Te samples. This high performance material is earth-abundant, low cost and nontoxic, which is more propitious to thermoelectric generator applications.

Salicylic acid (SA) is a key defense hormone associated with wheat resistance against Fusarium head blight, which is a severe disease mainly caused by Fusarium graminearum. Although F. graminearum can metabolize SA, it remains unclear how this metabolic activity affects the wheat&ndash, F. graminearum interaction. In this study, we identified a salicylate hydroxylase gene (FG05_08116, FgNahG) in F. graminearum. This gene encodes a protein that catalyzes the conversion of SA to catechol. Additionally, FgNahG was widely distributed within hyphae. Disrupting the FgNahG gene (&Delta, FgNahG) led to enhanced sensitivity to SA, increased accumulation of SA in wheat spikes during the early infection stage and inhibited development of head blight symptoms. However, FgNahG did not affect mycotoxin production. Re-introducing a functional FgNahG gene into the &Delta, FgNahG mutant recovered the wild-type phenotype. Moreover, the expression of FgNahG in transgenic Arabidopsis thaliana decreased the SA concentration and the resistance of leaves to F. graminearum. These results indicate that the endogenous SA in wheat influences the resistance against F. graminearum. Furthermore, the capacity to metabolize SA is an important factor affecting the ability of F. graminearum to infect wheat plants.

Inspired by concerns about food safety, the metabolic landscape of biogenic amines (BAs) was elucidated during industrial semidry Chinese rice wine fermentation. The main fermentation process represented the largest contribution to BA formation, which corresponded to 69.1% (54.3 mg/L). Principal component analysis revealed that total acid and ethanol were strongly correlated with BAs, indicating that BA formation favored acidic and stressful conditions. Other than putrescine (PUT), spermidine (SPD), and spermine (SPM), 5 BAs exhibited strong relationships with the precursor amino acids (R2 > 0.85). PUT was mainly decarboxylated from arginine (89.6%) whereas SPD (100%) and SPM (83.1%) were obtained from ornithine. Interestingly, some SPD could convert back to PUT (24.3%). All 8 BAs showed good relationships with lactic acid bacteria (LAB) (R2 around 0.75). Moreover, among the five main LAB genera, Lactobacillus had a positive correlation with BA formation.

MXene, a new two-dimensional (2D) material, has been extensively studied in the field of energy storage. However, the restacking and inferior stability of MXene severely affect their development. Herein, we fabricated a Ti3C2Tx-rGO aerogel through ascorbic acid-assisted hydrothermal treatment. It could effectively reduce the restacking of MXene and enhance the electrochemical properties of electrode material. The redox kinetics of electrode materials were analyzed. The diffusion-controlled process contributions from Ti3C2Tx/rGO-4 were significantly higher than Ti3C2Tx owing to the more exposed active sites after reduced graphene oxide (rGO) intercalation and increased layer spacing. Ti3C2Tx/rGO-4 aerogel binder-free electrode achieved a special capacitance of 313 F g−1 (about 174 % of Ti3C2Tx) at 1 A g−1. Moreover, Ti3C2Tx/rGO-4 symmetric supercapacitor demonstrated an outstanding energy density of 7.5 Wh kg−1 at a power density of 500 W kg−1 when the operated potential was at 1 V, showing a good application prospect.

A kind of photoswitchable nanoparticles which are the fluorescent carbon nanoparticles grafted with the copolymers of styrene and spiropyran (f-CNP-g-poly(St-co-SP) is reported. The f-CNP-g-poly(St-co-SP) not only feature the reversibly photoswitchable fluorescence, but also have good processability. Their fluorescence could be reversibly switched between blue-green and red by using ultraviolet/visible light irradiation. Furthermore, they could be readily processed into nanofibers with reversibly photoswitchable fluorescence by electrospinning. They can be potentially applied in fabricating microdevice, optical switching, information storage, anti-counterfeiting as well as biological imaging.

Silicon quantum dots (Si QDs) were synthesized by a facile one-step synthesis that involved etching silicon powder through a hydrothermal method. The Si QDs, without any surface modification, maintained good water dispersibility, strong photoluminescence and high pH stability, and can be used as a sensor to detect Cu2+.

Fluorescent carbon nanoparticles (f-CNPs) were successfully grafted with polystyrene by employing a “grafting from” method via reversible addition-fragmentation chain transfer polymerization (RAFT). The detailed polymerization kinetic studies showed that the grafting polystyrene polymerization from the f-CNPs surface via RAFT was living-controlled. The synthesized f-CNP-g-PSt nanocomposites with different grating lengths via RAFT could fluoresce like f-CNPs. At the same time, the synthesized f-CNP-g-PSt nanocomposites could be easily processed into fibers by electrospinning. The fibers could still fluoresce at the appropriate excitation wavelength. The f-CNP-g-PSt nanocomposites synthesized via RAFT feature good processability may be applied as luminescent plastic.

Monogalactosyldiacylglycerol (MGDG) is the most abundant lipid component of the thylakoid membrane. Although MGDG is believed to be important in sustaining the structure and function of the photosynthetic membrane, its exact role in photosynthesis in vivo requires further investigation. In this study, the transgenic tobacco plant M18, which has an MGDG deficiency of approximately 53%, and which contains many fewer thylakoid membranes and exhibits retarded growth and a chlorotic phenotype, was used to investigate the role of MGDG. Chlorophyll fluorescence analysis of the M18 line revealed that PSII activity was inhibited when the plants were exposed to light. The inactive linear electron transport found in M18 plants was mainly attributed to a block in the intersystem electron transport process that was revealed by P700 redox kinetics and PSI light response analysis. Immunoblotting and Blue Native SDS-PAGE analysis suggested that a reduction in the accumulation of cytochrome b6f in M18 plants is a direct structural effect of MGDG deficiency, and this is likely to be responsible for the inefficiency observed in intersystem electron transport. Although drastic impairments of PSII subunits were detected in M18 plants grown under normal conditions, further investigations of low-light-grown M18 plants indicated that the impairments are not direct structural effects. Instead, they are likely to result from the cumulative photodamage that occurs due to impaired photostability under long-term exposure to relatively high light levels. The study suggests that MGDG plays important roles in maintaining both the linear electron transport process and the photostability of the PSII apparatus.

Two cDNAs encoding putative type 1 acyl-CoA: diacylglycerol acyltransferases (DGAT1, EC 2.3.1.20), were cloned from Tetraena mongolica, an extreme xerophyte with high oil content in the stems. The 1 488-bp and 1 485-bp of the open reading frame (ORF) of the two cDNAs, designated as TmDGAT1a and TmDGAT1b, were both predicted to encode proteins of 495 and 494 amino acids, respectively. Southern blot analysis revealed that TmDGAT1a and TmDGAT1b both had low copy numbers in the T. mongolica genome. In addition to ubiquitous expression with different intensity in different tissues, including stems, leaves and roots, TmDGAT1a and TmDGAT1b, were found to be strongly induced by high salinity, drought and osmotic stress, resulting in a remarkable increase of triacylglycerol (TAG) accumulation in T. mongolica plantlets. TmDGAT1a and TmDGAT1b activities were confirmed in the yeast H1246 quadruple mutant (DGA1, LRO1, ARE1, ARE2) by restoring DGAT activity of the mutant host to produce TAG. Overexpression of TmDGAT1a and TmDGAT1b in soybean hairy roots as well as in T. mongolica calli both resulted in an increase in oil content (ranging from 37% to 108%), accompanied by altered fatty acid profiles.

Three series of bisazo reactive red dyes were synthesised using 6-amino-1-naphthol-3-sulphonic acid and its derivatives as the coupling components. The dyeing parameters and wash fastness of these dyes on knitted cotton were evaluated and the relationships between the structure and dyeing properties were investigated. It was found that the hydrophilic groups introduced into the dye molecules decrease the substantivity and fixation of the dyes, but increase the build-up and migration properties. The defined wash-off factor can directly reflect the wash fastness of the dyes and the build-up property can be improved by commercialisation using certain auxiliaries. The results indicate that there is the possibility of synthesising a red reactive dye with a satisfying balance between high fixation and good wash fastness and several such dyes have been developed.

A highly selective fluorescence sensor was developed for Hg(II) ion detection in aqueous solutions based on the selective binding of Hg(II) ions with a pair of thymine-thymine mismatch. The sensor consists of two DNA probes functionalized with a fluorophore (fluorescein, F) and a quencher (tetramethyl rhodamine, Q) moiety separately. This pair of DNA probes contains two pairs of thymine-thymine mismatches used to detect Hg(II) ions. In the presence of Hg(II) ions, thymine-Hg2+-thymine was formed between thymine residues of probes. From that, the interaction of the two DNA probes increased. Thus, the DNA probes formed a double-stranded structure. Both the fluorophore and quencher were brought close to each other leading to the fluorescence resonance energy transfer (FRET) between F and Q. Under the optimum conditions, the sensor was used to detect the Hg(II) ions from 50 to 1000 nmol·L−1 with a regression equation y=5281.13−1650.56 lg[Hg2+] (R2=0.985). The linear range covers 100 to 500 nmol·L−1, and the limit of detection (LOD) is 79 nmol·L−1. The disturbance of some co-existing metal ions was explored, and no significant fluorescence quenching in the presence of 1.0 μmol·L−1 other metal ions was observed. The fluorescence sensor has good sensitivity and selectivity for Hg(II) ions providing a rapid, simple and low cost method for the detection of mercury(II) ions in aqueous solutions.

In order to improve the hydrogenation and dehydrogenation performances of the Mg 2 Ni-type alloys, Mg in the alloy was partially substituted by element La, and rapid quenching technology was used for the preparation of the Mg 20− x La x Ni 10 ( x = 0, 2, 4, 6) hydrogen storage alloys. The structures and morphologies of the as-cast and quenched alloys were studied by XRD and high-resolution transmission electronic microscope (HRTEM). Thermal stability of the as-quenched alloys was researched by differential scanning calorimetry (DSC). The hydrogen absorption and desorption kinetics of the alloys were measured using an automatically controlled Sieverts apparatus. The results show that no amorphous phase forms in the as-quenched La-free alloy, but the as-quenched alloys containing La hold a major amorphous phase, which is attributed to the fact that the substitution of La for Mg significantly heightens the glass forming ability of the Mg 2 Ni-type alloy. The quenching rate induced a light influence on the crystallization temperature of the amorphous phase, but it significantly improved the hydrogenation and dehydrogenation capacities and the kinetics of the alloys. When the quenching rate increases from 0 (as-cast was defined as quenching rate of 0 m/s) to 30 m/s, the hydrogen capacity of the alloys ( x = 0) at 200 °C and 1.5 MPa in 10 min rises from 1.21 to 3.10 wt.%, and from 1.26 to 2.60 wt.% for the alloy ( x = 2). The hydrogen desorption capacity of the alloy ( x = 0) in 10 min increases from 0.23 to 0.99 wt.%, and from 1.48 to 2.46 wt.% for the alloy ( x = 2), respectively.

In order to investigate the influences of the stoichiometric ratios of B/A (A: gross A-site elements, B: gross B-site elements) and the substitution of Co for Ni on the structure and the electrochemical performances of the AB 2.5 – 3.5 -type electrode alloys, the La–Mg–Ni–Co system La 0.75 Mg 0.25 Ni 2.5 M x ( M = Ni , Co; x = 0 , 0.2, 0.4, 0.6, 0.8, 1.0) alloys were prepared by induction melting in a helium atmosphere. The structures and electrochemical performances of the alloys were systemically measured. The obtained results show that the structures and electrochemical performances of the alloys are closely relevant to the M content. All the alloys exhibit a multiphase structure, including LaNi 2 , ( La , Mg ) Ni 3 and LaNi 5 phases, and the major phase in the alloys changes from LaNi 2 to ( La , Mg ) Ni 3 + LaNi 5 with the variety of M content. The electrochemical performances of the alloys, involving the discharge capacity, the high rate discharge (HRD) ability, the activation capability and the discharge potential characteristics, significantly improve with increasing M content. When M content x increases from 0 to 1.0, the discharge capacity rises from 177.7 to 343.62 mAh/g for the alloy ( M = Ni ) , and from 177.7 to 388.7 mAh/g for the alloy ( M = Co ) . The cycle stability of the alloy first mounts up then declines with growing M content. The substitution of Co for Ni significantly ameliorates the electrochemical performances. For a fixed M content ( x = 1.0 ) , the substitution of Co for Ni enhances the discharge capacity from 343.62 to 388.7 mAh/g, and the capacity retention ratio ( S 100 ) after 100 charging–discharging cycles from 51.45% to 61.1%.

The effects of the substitution of Mn for Ni on the structures and electrochemical characteristics of the as-cast and quenched La 0.5 Ce 0.2 Mg 0.3 Co 0.4 Ni 2.6 - x Mn x ( x = 0 , 0.1, 0.2, 0.3, 0.4) alloys were studied systematically. The results obtained by XRD, SEM and TEM indicate that the as-cast and quenched alloys mainly consist of two major phases the ( La , Mg ) Ni 3 and LaNi 5 and a residual phase LaNi. With increasing Mn content in the alloys, the abundance of the ( La , Mg ) Ni 3 phase decreases and that of the LaNi 5 phase increases and both the lattice parameters and the cell volumes of major phases ( La , Mg ) Ni 3 and LaNi 5 increase. The as-quenched alloys display a nanocrystalline structure, and the grain sizes of the alloys are in a range of 20–30 nm. The results by the electrochemical measurements indicate that the discharge capacities of the as-cast and quenched alloys first increase and then decrease with the variety of Mn content and obtain the maximum values for a Mn content of x = 0.2 . The substitution of Mn for Ni clearly improves the high rate discharge abilities (HRDs) and the activation capabilities of the as-cast and quenched alloys, but it slightly impairs the cycle stabilities of the as-cast and quenched alloys.

Objective To quantitatively evaluate the diagnostic value of gemstone spectral CT in thyroid disease. Patients and methods A total of 123 patients with thyroid diseases were enrolled in the retrospective study. All the patients underwent spectral CT scan, and 39 of them underwent dual-phase enhanced scan. Iodine concentration (IC) and normalized IC (NIC) were compared between benign and malignant nodules. The optimal threshold to predict malignancy was obtained by receiver operating characteristic curve (ROC). Multivariate ROC analysis was performed to evaluate the efficacy of combining the IC (NIC) and conventional morphological characteristics. Results Ten diffuse diseases and 113 nodular diseases were confirmed by clinical laboratory examination and histopathology. In total, 122 nodules (87 benign and 35 malignant) were detected, 41 nodules in enhanced cases. The IC and NIC _{VP} of malignant nodules were significantly lower than benign nodules in noncontrast and venous phase (VP) (P=0.000). The optimal IC and NIC _{VP} threshold was 0.68 mg/mL and 0.38, achieving 74.3% and 76.9% sensitivity, 66.7% and 80.0% specificity, respectively. For multivariate analysis, the area under ROC (AUC) was 0.88 and 0.94 in noncontrast and VP, respectively. Sensitivities of 77.1% and 84.6%, and specificities of 84.5% and 88.0% were achieved. Conclusion Gemstone spectral CT can generally evaluate the abnormal iodine content in thyroid disease. Lower iodine can help differentiating malignant from benign nodules. A comprehensive analysis combining spectrum parameters and morphological characteristics is suggested in differential diagnosis.

[11C]-choline has been reported as a potential tracer for imaging a variety of human tumors with positron emission tomography (PET). A new labeling technique for [11C]-choline was established depending on parameters optimized, such as reaction time, volume, temperature, and the quantity of DMAE.The synthesis yield was improved from 82.0% to 96.5% (EOB), while the consumption of DMAE precursor decreased from 60 to 2 mg. Absolute yield of [11C]-choline was 2500 MBq for a 10-minute irradiation at15mA, and a total synthesis time of less than 8 minutes from [11C]-CH3I to [11C]-choline.

A competitive indirect chemiluminescent enzyme immunoassay (ic-CLEIA) has been developed for the determination of chloramphenicol (CAP) residues in shrimp. After the optimisation of four physico-chemical parameters, i.e. incubation time, concentration of Tween-20, concentration of PBS and its pH, the method developed gave a limit of detection of 0.01 ng/ml and a detection range from 0.03 ng/ml to 23.7 ng/ml, with an ED 5 0 of 0.47 ng/ml. The developed method has been validated on spiked shrimp samples in terms of precision (intra- and interassay coefficient variations of less than 10% and 15%, respectively), and of accuracy (mean recovery from 95% to 123%). All these parameters being better than those of the ELISA method which is widely used to detect chloramphenicol, it may be suggested that the CLEIA method can be used to detect aquatic samples instead of ELISA.

A competitive indirect chemiluminescence enzyme immunoassay (ic-CLEIA) for chloramphenicol (CAP) residues in shrimp has been developed. After optimization (incubation time, concentration of Tween-20, concentration of PBS and pH), the method gave a limit of detection of 0.01 ng/mL and a detection range of 0.03-23.7 ng/mL, with an ED(50) of 0.47 ng/mL. The method has been validated on spiked shrimp samples in terms of precision (intra- and interassay coefficient variations of less than 10% and 15%, respectively) and accuracy (mean recovery 95-123%). The assay performance is better than the ELISA method which is widely used to detect chloramphenicol and indicates that the CLEIA method can be used to test aquatic samples instead of ELISA.

Purpose: To assess the accuracy of the quantification of the iodine concentration of contrast agent using gemstone spectral imaging under static and pulsating conditions respectively. Methods: A phantom with nine test tubes containing iodine contrast in various concentrations (0.4, 0.7, 2.5, 10, 20, 30, 50 and 100 mg/ml) was scanned with gemstone spectral imaging mode of Discovery CT750 HD. All the scans were performed at static and pulsating status at gantry rotation time of 0.6 s, 0.8 s and 1.0 s respectively. Data were transferred to a work station to acquire iodine-based images, and the iodine contrast was measured within samesized regions of interest at the same level. The relation and discrepancy between measured concentrations and real concentrations of the iodine contrasts were analyzed. Results: At gantry rotation time of 0.8 s and 1.0 s, either at static status or pulsating status, the measured concentrations were significantly correlated with the real concentrations (p=0.000, r=0.999), without significant statistic difference (p>0.05). However, at gantry rotation time of 0.6 s, there was a statistically significant difference between the measured values and the real values (p

The anilines could be easily and selectively N-alkylated with alcohols in the presence of a small amount of Raney nickel and with a greatly shortened period under microwave irradiation. A purely non-thermal effect of microwave was observed in the reaction.

It was the first time that the Influences of main factors, such as pH of solution, the value of C/N, the different kinds of carbon sources and temperature on removing NO 3 − in polluted groundwater from in-situ leaching uranium mine by denitrifying bacteria (DNB), have been studied domestically. The tests results showed that the optimum pH was between 6 to 8. When pH≦5, the removing rate of NO 3 − decreased. The end pH value of solution was about 7. When C/N≥1, the removing rate of NO 3 − was more than 90%. The optimum value of C/N was about 1∼1.5. The different kinds of carbon sources affected the removing rate of NO 3 − and the removing effect of NO 3 − was the best when sodium lactate was used as carbon source. When Oxidation-Reduction Potential (ORP) was −50 mV∼−200 mV, the lower the ORP was, the faster the removal rate of NO 3 − was by DNB. Dissolved oxygen (DO) affected the removal rate of NO 3 −. When DO>1 mg·L−1, the removing effect of NO 3 − was restrained. The removing rate of NO 3 − increased with the increasing of the temperature. When the experimental temperature was 17 °C, the removing Influences of NO 3 − was also good. It was good for removing NO 3 − in polluted groundwater in in-situ leaching uranium mine by DNB.

Removing NO 3 − in polluted groundwater of in-situ leaching uranium mine with iron powder (zero-valent iron, Fe0), DNB, iron powder and DNB are studied. The condition of tests include different pH of solution, dosage of iron powder, and treating time. The experimental results show that over 93% of NO 3 − in unneutralized polluted groundwater (pH value about 1.46) can be removed with 16.5 g·L−1 iron powder in 4 days. NO 3 − in neutralized polluted groundwater (pH value about 7.62) can also be removed with 2 g·L−1 iron powder. The removing rate of NO 3 − is enhanced with time and the highest removing rate reaches 54% in 5 days. NO 3 − in neutralized polluted groundwater can also be removed with DNB in condition of ρ(COD)/ρ(NO3-) equal to 1.5, 35°C, pH 5-8. The removing rate of NO 3 − is over 90%in 5 days. In certain conditions, the removing rate of NO 3 − with DNB is 30% higher than that with iron powder. The removing rate is promoted with DNB adding iron powder. Comparing to DNB, the iron powder can be used in larger range of pH of the polluted groundwater.

Photooxidation products of biogenic volatile organic compounds were characterized and measured in PM2.5 (particulate matter with an aerodynamic diameter les2.5 mum aerosol samples from forests. Aerosol sampling was conducted at four sites centred in and around major research stations located in four different regions of China: Xiaoxing'an Ling (boreal), Dongping national forest park (temperate), Dinghu mountain (subtropical) and Wuzhi mountain nature reserve (tropical) during summer periods when the meteorological conditions are believed to be favorable for photochemical processes. Thirty samples were collected; particular matter (PM), organic carbon, elemental carbon, organic compounds, inorganic ions, and trace gases were measured. Results indicate that the average concentrations of isoprene and alpha-pinene oxidation products, sugars and sugar alcohols vary systematically along gradients of ecological succession, except malic acid which may have both biogenic and anthropogenic origins. The maximum contributions of organic components, isoprene and alpha-pinene oxidation products, sugars, sugar alcohols, and inorganic ions, SO42-, NO3-, C2O42-, to the PM was 28%.

Photooxidation products of biogenic volatile organic compounds, mainly isoprene and monoterpenes, are significant sources of atmospheric particulate matter in forested regions. The objectives of this study were to examine time series and diel variations of polar organic tracers for the photooxidation of isoprene and á-pinene to investigate whether they are linked with meteorological parameters or trace gases, and to determine their carbon contributions. In addition, the biogenic secondary organic carbon contributions from isoprene were estimated. PM2.5 (particulate matter with an aerodynamic diameter

A 3.3-3.8GHz 2W MMIC power amplifier using AlGaAs/InGaAs/GaAs PHEMT for wireless local-area network and multi-channel multipoint distribution service applications is demonstrated. This two-stage amplifier is designed to match fully a 50/spl Omega/ input and output impedance. With dual-bias configuration, the amplifier possesses a 30.4dB small-signal gain, and a 34dBm 1-dB gain compression power with 37.1% power-added efficiency. Moreover, high linearity with a 41.5dBm third-order intercept point at a frequency of 3.5GHz is obtained.

A high linearity, high efficiency 1.9 GHz power amplifier sub-system using a 50 mm AIGaAs/InGaAs/GaAs PHEMT for PHS 500 mW base station is demonstrated. Under 10 V and 3.8 A bias condition, the output stage amplifier has achieved 12.5 dB small-signal gain, 43.7 dBm PldB with 43% PAE and 44 dBm saturated output power with 41% PAE. For the amplifier sub-system, the ACPR at 600 KHz and 900 KHz offset from 1.906 GHz when operating at 38.5 dBm output power with /spl Pi//4-DQPSK signal are better than 75 dBc and 79 dBc, respectively.

A trace gas sensor, based on quartz-enhanced photoacoustic spectroscopy (QEPAS) with two non-resonant micro-tubes, was designed to detect the ammonia concentration in impure helium. Unlike the traditional micro-resonator, the non-resonant micro-tubes are used to confine the sound wave, but do not exhibit a well-defined resonant behavior. Such a design makes the dimension of the spectrophone much smaller than the micro-resonant configuration, which facilitates the optical alignment. Signal and noise, that were dependent on gas pressure, were also investigated to optimize sensor performance. With the optimal sensor parameters and the optimal gas pressure, the detection sensitivity was found to be 463 ppb (1 , 1 s averaging time), which corresponds to the normalized absorption sensitivity of 4.310-9cm-1W/Hz.

Sectral interferences were shown to be caused primarily by fluorescence of the interfering species within the spectral band pass of the monochromator. When the spectral band pass of the monochromator was limited to 0.1 nm there were no significant spectral interferences.The choice of a single or double monochromator for discrimination against stray light depends on different considerations when a line source is used compared with a continuum source. Improvements in the signal to noise ratio when using a double monochromator were less when a continuum source was in use.Use of the short-arc xenon arc for the excitation of elements that have analytical lines below 214 nm was possible and gave parts per million level detection limits, but only during the first 14 h of lamp life. Radio-frequency-excited electrodeless discharge lamps gave similar or better detection limits in the UV region. A hybrid multi-element instrument with both types of light source is therefore better for the determination of the greatest number of elements.

The content and retention of manganese in the blood and brain of mice exposed to different forms of the metal was compared. Mice received an acute sc injection of manganese as the chloride or oxide (Mn3O4) or as the organic MMT. A single injection markedly elevated brain manganese concentrations within 1 day and elevated levels were maintained for at least 21 days. Repeated injections led to further increases in both brain and blood, although the levels in the brain appeared to persist at consistently high levels for longer periods. The chloride form produced higher brain levels than either of the other two forms. These results appear to suggest that the slowly developing neurotoxicity in response to manganese exposure may be due to a persistent retention of manganese by the brain.

In this work, we show that the introduction of acidic oxygen functionalities to the surface of carbon nanofibers serves to depress the hydrogenation and the decomposition of hydrogen peroxide during the direct synthesis of H2O2. Moreover, the presence of acidic groups enhances the H2O2 productivity in the case of supported AuPd nanoparticles.