Hydrothermal Synthesis of Silver Vanadium Oxide (Ag0.35V2O5) Nanobelts for Sensing Amines

A simple hydrothermal method for the synthesis of Ag0.35V2O5 nanobelts with the assistance of sodium dodecyl sulfate (SDS) is reported in this study. The experimental variables that may affect the nanoparticle structures were investigated. And several advanced techniques, such as TEM, HRTEM, X-ray diffraction (XRD), were used to characterize the morphology and composition of the as-prepared nanobelts. The mechanism of the formation and growth of Ag0.35V2O5 nanobelts was also investigated and discussed. The results show that SDS, as a weak reducing agent, plays a crucial role in the formation of Ag0.35V2O5. According to N2 sorption isothermals, the as-prepared Ag0.35V2O5 nanobelts are found to exhibit relative high surface area. The gas sensing performance of the Ag0.35V2O5 nanobelts towards organic amine was tested. It is found that the nanobelts show superior sensitivity of amine(s) to V2O5 particles, lower detection limit (5 ppm), and higher selectivity of amine versus ammonia at an optimized working temperature of ~260 °C. Moreover, the density functional theory (DFT) simulation was conducted to better understand the sensing mechanism. These findings may be useful in designing promising materials to detect amine gases for medical or food industrial applications.

Structural characterization of the packings of granular regular polygons

By using a recently developed method for discrete modeling of nonspherical particles, we simulate the random packings of granular regular polygons with three to 11 edges under gravity. The effects of shape and friction on the packing structures are investigated by various structural parameters, including packing fraction, the radial distribution function, coordination number, Voronoi tessellation, and bond-orientational order. We find that packing fraction is generally higher for geometrically nonfrustrated regular polygons, and can be increased by the increase of edge number and decrease of friction. The changes of packing fraction are linked with those of the microstructures, such as the variations of the translational and orientational orders and local configurations. In particular, the free areas of Voronoi tessellations (which are related to local packing fractions) can be described by log-normal distributions for all polygons. The quantitative analyses establish a clearer picture for the packings of regular polygons.

Carbon-Coated Gold Nanorods: A Facile Route to Biocompatible Materials for Photothermal Applications

Gold nanorods and their core-shell nanocomposites have been widely studied because of their well-defined anisotropy and unique optical properties and applications. This study demonstrates a facile hydrothermal synthesis strategy for generating carbon coating on gold nanorods (AuNRs@C) under mild conditions (<200 °C), where the carbon shell is composed of polymerized sugar molecules (glucose). The structure and composition of the produced core-shell nanocomposites were characterized using advanced microscopic and spectroscopic techniques. The functional properties, particularly the photothermal and biocompatibility properties of the produced AuNRs@C, were quantified to assess their potential in photothermal hyperthermia. These AuNRs@C were tested in vitro (under representative treatment conditions) using near-infrared (NIR) light irradiation. It was found that the AuNRs produced here exhibit exemplary heat generation capability. Temperature changes of 10.5, 9, and 8 °C for AuNRs@C were observed with carbon shell thicknesses of 10, 17, and 25 nm, respectively, at a concentration of 50 μM, after 600 s of irradiation with a laser power of 0.17 W/cm(2). In addition, the synthesized AuNRs@C also exhibit good biocompatibility toward two soft tissue sarcoma cell lines (HT1080, a fibrosarcoma; and GCT, a fibrous histiocytoma). The cell viability study shows that AuNRs@C (at a concentration of <0.1 mg/mL) core-shell particles induce significantly lower cytotoxicity on both HT1080 and GCT cell lines, as compared with cetyltrimethylammonium bromide (CTAB)-capped AuNRs. Furthermore, similar to PEG-modified AuNRs, they are also safe to both HT1080 and GCT cell lines. This biocompatibility results from a surface full of -OH or -COH groups, which are suitable for linking and are nontoxic Therefore, the AuNRs@C represent a viable alternative to PEG-coated AuNRs for facile synthesis and improved photothermal conversion. Overall, these findings open up a new class of carbon-coated nanostructures that are biocompatible and could potentially be employed in a wide range of biomedical applications.

Thymic stromal lymphopoietin (TSLP) secretion from human nasal epithelium is a function of TSLP genotype

Recent candidate gene and genome-wide association studies have identified "protective" associations between the single-nucleotide polymorphism (SNP) rs1837253 in the TSLP gene and risk for allergy, asthma, and airway hyperresponsiveness. The absence of linkage disequilibrium of rs1837253 with other SNPs in the region suggests it is likely a causal polymorphism for these associations, having functional consequences. We hypothesized that rs1837253 genotype would influence TSLP secretion from mucosal surfaces. We therefore evaluated the secretion of TSLP protein from primary nasal epithelial cells (NECs) of atopic and nonatopic individuals and its association with rs1837253 genotype. We found that although atopic sensitization does not affect the secretion of TSLP from NECs, there was decreased TSLP secretion in NECs obtained from heterozygous (CT; 1.8-fold) and homozygous minor allele (TT; 2.5-fold) individuals, as compared with NECs from homozygous major allele individuals (CC; P<0.05), after double-stranded RNA (dsRNA) stimulation (50 μg ml(-1)). Our novel results show that rs1837253 polymorphism may be directly involved in the regulation of TSLP secretion. This may help explain the protective association of this genetic variant with asthma and related traits. Identifying functional consequences of SNPs in genes with previously reported clinical associations is critical in understanding and targeting allergic inflammation.

Metabolic syndrome is an independent prognostic factor for endometrial adenocarcinoma

OBJECTIVE

To study the association between metabolic syndrome (MS) and the prognosis of patients with endometrial adenocarcinoma.

METHODS

A total of 385 patients with endometrial adenocarcinoma in the Department of Gynecologic Oncology, at the Zhejiang Cancer Hospital in China, between January 2001 and December 2008 were chosen. The deadline for the completion of follow-up was December 2013. The overall survival (OS) of the patients with MS was analyzed by the Kaplan-Meier method. Various clinical characteristics (e.g., clinical and surgical stage, vascular invasion, histological grade, tumor size, age at start of the first treatment, and lymphatic metastasis) related to the prognosis of endometrial adenocarcinoma were also evaluated.

RESULTS

A univariate analysis demonstrated that the OS rate of the patients with endometrial adenocarcinoma with MS was significantly worse than that of the patients without MS for all 385 patients (P = 0.001). Multivariate Cox proportional hazards regression analyses showed that stage (P = 0.001), lymphatic metastasis (P = 0.021), and MS (P = 0.049) were independent prognostic factors for endometrial adenocarcinoma. Furthermore, statistical analyses demonstrated that MS was closely related to stage (P = 0.021), grade (P = 0.022), vascular invasion (P = 0.044), tumor size (P = 0.035), and lymphatic metastasis (P = 0.014) but not with age at start of the first treatment (P = 0.188). Finally, according to the univariate analysis of the OS rate of 129 cases of endometrial adenocarcinoma with MS, stage (P = 0.001), vascular invasion (P = 0.049), tumor size >2 cm (P = 0.028), lymphatic metastasis (P = 0.002), and CA19-9 value >37 U/m (P = 0.002) all showed significantly low P values for OS.

CONCLUSION

Metabolic syndrome is an independent prognostic factor for endometrial adenocarcinoma.

Direct Hydrothermal Synthesis of Carbonaceous Silver Nanocables for Electrocatalytic Applications

This study demonstrates a facile but efficient hydrothermal method for the direct synthesis of both carbonaceous silver (Ag@C core-shell) nanocables and carbonaceous nanotubes under mild conditions (<180 °C). The carbonaceous tubes can be formed by removal of the silver cores via an etching process under temperature control (60-140 °C). The structure and composition are characterized using various advanced microscopic and spectroscopic techniques. The pertinent variables such as temperature, reaction time, and surfactants that can affect the formation and growth of the nanocables and nanotubes are investigated and optimized. It is found that cetyltrimethylammonium bromide plays multiple roles in the formation of Ag@C nanocables and carbonaceous nanotubes including: a shape controller for metallic Ag wires and Ag@C cables, a source of Br(-) ions to form insoluble AgBr and then Ag crystals, an etching agent of silver cores to form carbonaceous tubes, and an inducer to refill silver particles into the carbonaceous tubes to form core-shell structures. The formation mechanism of carbonaceous silver nanostructures depending upon temperature is also discussed. Finally, the electrocatalytic performance of the as-prepared Ag@C nanocables is assessed for the oxidation reduction reaction and found to be very active but much less costly than the commonly used platinum catalysts. The findings should be useful for designing and constructing carbonaceous-metal nanostructures with potential applications in conductive materials, catalysts, and biosensors.

Receptor-interacting protein kinase 3 is a predictor of survival and plays a tumor suppressive role in colorectal cancer

Receptor-interacting protein kinase 3 (RIP3) is a member of the RIP Ser/Thr kinase family, plays an important role in regulating cell survival, cell apoptosis and cell necrosis. However, the role of RIP3 in the carcinogenesis of colorectal cancer is still poorly understood.We used quantitative PCR and Western blot analysis to examine RIP3 expression in primary colorectal cancer and paired normal colorectal mucosa. RIP3 clinicopathological significance was assessed by immunohistochemical staining in 112 cases of primary colorectal cancer paired with noncancerous tissues. The biological function of RIP3 overexpression was measured by CCK8 assay and plate colony formation assay. Dual staining with fluorescent Annexin V and propidium iodide (PI) was used to discriminate apoptotic or necrotic cell death.RIP3 expression was significantly lower in colorectal cancer and associated with T stage, M stage and AJCC stage. Cox proportional hazard models showed that RIP3 expression was an independent prognostic factor for overall survival and disease-free survival in patients with colorectal cancer. Overexpression of RIP3 significantly suppressed the proliferation of colorectal cancer cells in vitro.Our results suggest that RIP3 may function as a novel prognostic indicator after surgery and play a suppressive role in the colorectal carcinogenesis.

Biomorphic synthesis of mesoporous Co₃O₄ microtubules and their pseudocapacitive performance

A novel meosoporous tubular Co3O4 has been fabricated by a simple and cost-effective biomorphic synthesis route, which consists of infiltration of cotton fiber with cobalt nitrate solution and postcalcination at 673 K for 1 h. Its electrochemical performance as a supercapacitor electrode material is investigated by means of cyclic voltammetry and chronopotentiometry tests. Compared with bulk Co3O4 prepared without using cotton template, biomorphic Co3O4 displays 2.8 fold enhancement of pseudocapacitive performance because of the unique tubular morphology, relative high specific surface area (3 and 0.8 m(2)/g for biomorphic Co3O4 and bulk Co3O4, respectively), and mesoporous nature.

Why have continuum theories previously failed to describe sandpile formation?

Granular piling may or may not induce a counterintuitive phenomenon of pressure dip at the center of a pile base. Understanding the behavior is a long-standing challenge in granular dynamics modeling. Here we show that the experimental observations of dip or nondip piles can be satisfactorily reproduced by the classic elastoplastic models. Our results demonstrate that (i) dynamic history is a critical factor in the successful description of a piling process and (ii) the dip phenomena are complicated, involving numerous variables associated not only with piling operation but also material properties. Our findings can explain why previous attempts failed to describe piling processes and may open up a new direction to describe granular materials in nature and many industrial processes.

An ab initio study of transition metals doped with WSe2 for long-range room temperature ferromagnetism in two-dimensional transition metal dichalcogenide

We report a systematic study of the magnetic properties in transition metals doped with WSe2 through the use of first principle calculations. The results demonstrate the possibility of generating long-range room temperature ferromagnetic interaction in WSe2 with the use of Mn and Fe doping. In the case of Fe, a percolation threshold is required for long-range ferromagnetism, whereas the long-range room temperature ferromagnetic interaction in Mn-doped WSe2 persists even at a low concentration (~5.6%). The ferromagnetism is mediated by the delocalized p states in the Se atoms, which couple antiferromagnetically with the spin-down a1 and e1 states in Fe doping through a correlated interaction. In Mn doping, the p states of Se tend to couple ferromagnetically with the 3d state of Mn, which stabilizes the long-range ferromagnetism between the Mn ions, although the short-range interaction is antiferromagnetic. In addition, the calculations indicate that Fe and Mn tend to configure at a high spin state, thus they possess much larger magnetic moments in WSe2 than when they are doped into other transition metal dichalcogenides. We also discovered a strong dependence of the exchange interaction on the dopants' spatial positions, distances, and concentrations, which alters the magnetic coupling from strong ferromagnetism to strong antiferromagnetism. These results can provide useful guidance to engineer the magnetic properties of WSe2 in future experiments.

Crystal plane-dependent gas-sensing properties of zinc oxide nanostructures: experimental and theoretical studies

Crystal plane-dependent gas-sensing performance of ZnO nanostructures toward ethanol has been investigated experimentally and theoretically through DFT simulation.