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Constructing single-molecule parallel circuits with multiple conduction channels is an effective strategy to improve the conductance of a single molecular junction, but rarely reported. We present a novel through-space conjugated single-molecule parallel circuit (f-4Ph-4SMe) comprised of a pair of closely parallelly aligned p-quaterphenyl chains tethered by a vinyl bridge and end-capped with four SMe anchoring groups. Scanning-tunneling-microscopy-based break junction (STM-BJ) and transmission calculations demonstrate that f-4Ph-4SMe holds multiple conductance states owing to different contact configurations. When four SMe groups are in contact with two electrodes at the same time, the through-bond and through-space conduction channels work synergistically, resulting in a conductance much larger than those of analogous molecules with two SMe groups or the sum of two p-quaterphenyl chains. The system is an ideal model for understanding electron transport through parallel π-stacked molecular systems and may serve as a key component for integrated molecular circuits with controllable conductance.

Fuel cells are environmentally friendly energy systems with high energy efficiency, which are expected to play important roles in the sustainable society. However, CO-caused poisoning catalysts have been important problems in fuel cells, which hinder the practical applications of fuel cells. In this study, we studied the process of HCHO dissociation on the Pt electrode under different potentials using the electrochemical cell which can control the potential and replace the solution efficiently. The experimental results showed that with the positive shift of potential, the CO coverage on Pt due to the dissociation of HCHO slightly decreases from 71% at −0.2 V to 60% at 0.25 V. A sharp decline of the coverage of CO appears at 0.3 V. The coverage of CO is only 8%, which is far less than 64% at the open-circuit potential (ocp). The experimental results indicated that we can apply different control potential to manipulate the CO coverage and thus propose a new method of operation to reduce the CO poisoning. Verification experiments in formaldehyde showed that the initial oxidation current was 3×10−4 A, close to the peak current of 4×10−4 A and far more than the current of 3×10−5 A at the ocp experiment, after the addition of formaldehyde with potential control at 0.35 V for 300 s. Adding formaldehyde with potential control at 0.35 V can reduce the poisoning effect of CO on the catalyst effectively. This result may practically be applied in the commercial fuel cells.

BACKGROUND Worldwide, mortality from cervical cancer in women remains high. This study aimed to investigate the expression of long noncoding RNA (lncRNA) TP73-AS1, microRNA-329-3p (miRNA-329-3p), and the SMAD2 gene and their regulatory relationships in human cervical cancer tissue and cervical cancer cell lines. MATERIAL AND METHODS Cervical cancer tissue samples (n=30) and normal control cervical tissues were studied. Cell proliferation and migration were investigated in HeLa and SiHa human cervical cancer cells using the MTT assay, crystal violet staining, wound healing assay, and the transwell assay. Expression of lncRNA TP73-AS1 and the SMAD2 gene were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Enrichment of miR-329-3p was measured using the RNA immunoprecipitation assay (RIPA). Targeting relationships between TP73-AS1, miR-329-3p, and SMAD2 were identified using the dual-luciferase reporter assay. A subcutaneous xenograft model was established, tumor size was measured, and SMAD2 expression was detected using immunohistochemistry. RESULTS LncRNA TP73-AS1 was overexpressed in cervical cancer tissues and cells and was associated with reduced expression of miR-329-3p. Down-regulation of lncRNA TP73-AS1 inhibited cell proliferation, migration and invasion and increased miR-329-3p expression. Expression of SMAD2 down-regulated miR-329-3p and was associated with increased expression of TP73-AS1. LncRNA TP73-AS1 knockdown resulted in miR-329-3p silencing. In tumor xenografts, expression of TP73-AS1 reduced the tumor volume and down-regulated the expression levels of the SMAD2 gene. CONCLUSIONS LncRNA TP73-AS1 promoted proliferation of cervical cancer cell lines by targeting miR-329-3p to regulate the expression of the SMAD2 gene. A regulatory network was formed between lncRNA TP73-AS1, miR-329-3p, and SMAD2.

Germanium (Ge) has been considered as a promising material applied in lithium-ion batteries due to its unique properties, e.g. high capacity, fast lithium-ion diffusivity, and high electrical conductivity. In this work, Ge/GeO2/multi-layer graphite (Ge/GeO2/MLG) nanocomposites have been synthesized using a solution process from graphite oxide and GeO2 precursors. The electrochemical performances of the prepared Ge/GeO2/MLG nanocomposites were then investigated. The experimental results indicated that in the first cycle, the electrode delivered discharge and charge capacities of 2046 and 1146 mA h g−1, giving the Coulombic efficiency of 56.0%. After 50 cycles, the electrode capacity was still maintained at 1008 mA h g−1 at 100 mA g−1 in the potential range from 0.01 to 1.5 V, and it reached high capacities of 790 and 700 mA h g−1 at the high rates of 1 and 2 A g−1.

Resource restrictions and carbon restrictions are posing a challenge to corporate sustainable development. Therefore, enterprises will be able to become more competitive by enhancing their research and development of green technology as well as environmental performance. Taiwan is a high-tech island featuring the highly-intensive manufacturing, and Taiwan’s manufacturing industry is actively developing the green management. This study proposed the environmental performance indicators integrating five aspects: green product design, green product recycling, green manufacturing management, environmental protection and environmental management. A total of 239 valid questionnaires, collected from various manufacturing industries, were the research subjects to investigate their environmental performance. The study found respondents performed the best in environmental protection while the worst in green product recycling, and especially got the lowest score in the “Using biodegradable materials” indicator. The environmental performances of research subjects were positively correlated to their enterprise scales. However, the environmental performances of various industry categories showed no significant differences between with each other. The overall environmental performances of the enterprises that implemented ISO 14001 and 14064 certifications were significantly higher than those without certifications. These results indicate that the environmental management system could improve the environmental performance in manufacturing industry.

Reactions of copper(II) sulfate or copper(II) perchlorate, samarium(III), erbium(III) or neodymium(III) nitrate (5/1 equiv.) with pyrazinohydroxamic acid (H 2 Pyzha) in H 2 O/MeOH led to three new heterobimetallic 15-metallacrown-5 complexes. In a MeOH/H 2 O solution, when adding inorganic salts, the ligands exist as protonated metallacrowns. In the solid state, their structures are more complicated as confirmed by X-ray analysis: metallacrown [Sm (H 2 O) 3 {Cu(pyzha)} 5 (H 2 O) 2 (MeOH) (HSO 4 ) 2 ]·(H 2 O) 2 ·(HSO 4 ) ( 1 ); [Nd(H 2 O) 2 (MeOH) {Cu(pyzha)} 5 (ClO 4 ) 2 (H 2 O) 5 (NO 3 )] ( 2 ); [Eu(H 2 O) 2 (MeOH) {Cu(pyzha)} 5 (ClO 4 ) 2 (H 2 O) 5 (NO 3 )] ( 3 ). The differentiation of atomic and ionic radii between the encapsulated lanthanide(III) could be used to control the bowl-shape distortion of the metallacrowns from the planar geometry. The complex 1 clearly exhibits fluorescence behavior of samarium(III), while 2 and 3 show that of copper(II) and ligand.

Owing to its excellent electronic characteristics and wide spectrum of potential applications, graphene has attracted intense attention by not only scientists but also engineers. Growth of graphene films on copper foils using gaseous carbon sources has been emphasized previously due to the high quality/price ratio. In this study, we reported the synthesis of graphene films on copper substrate converting from a solid carbon source (polymethylmethacrylate) with help of hydrogen plasma. The effects of substrate temperature and microwave power on the growth of graphene have been investigated. Raman spectroscopic data indicated that high microwave power and substrate temperature would benefit the growth of high quality graphene films. X-ray photoelectron spectroscopic results implied that the synthesized graphene films were in high purity with small amount of oxygen contaminations. Transmission electron microscopy data suggested that the synthesized graphene films are polycrystalline and its atomic arrangement is in short-range order.

We report a successful approach in fabricating well shape two-dimensional Au nanocluster hexagonal array on an Si(111)-7 × 7 surface. The size of Au hexagons is about 2.5 × 2.5 nm2. The easiness of preparing large scale Au hexagonal array makes this approach usable to fabricate a wide range of other metal nanocluster arrays. Further deposition of small amount of Au nanoclusters on the Au hexagonal array surface will prefer to occupy the holes of the hexagonal array at room temperature. Finally, a reasonable structure of formatting the hexagonal Au nanocluster array on the Si(111)-7 × 7 surface was proposed. Copyright © 2015 John Wiley & Sons, Ltd.

Graphene films grown on the copper foils using chemical vapor deposition have been emphasized in the previous scientific studies and technical applications because of the high quality/cost ratio. However, no enough attention has been paid to the fundamentally important issue on the stability of graphene/copper interface compared with quality of the grown graphene films, though the properties of graphene/metal interface largely affect the Ohmic contacts in graphene-based electronics (e.g. high-frequency graphene transistors). Here, we investigated the electronic structure of graphene/copper interface which has been stored in the ambient conditions for different periods. Raman and photoelectron spectroscopic data indicated that the oxygen species do not prefer to adsorb on the graphene surface but insert into the graphene/copper interface. This results in the p-doping of graphene, formation of the surface positive dipole, and energy upshift of the graphene's Dirac point. Copyright © 2015 John Wiley & Sons, Ltd.

We have measured the conductance of pyrazine molecular junction contacting with Cu and Ag electrodes by using an electrochemical jump-to-contact based scanning tunneling microscopy break junction (ECSTM-BJ). While conductance values of 10-2.8 and 10-3.7 G0 are measured for pyrazineCu electrode, 10-2.1 and 10-3.3 G0 are found for pyrazine-Ag contact. The result shows that the conductance of pyrazine with Ag electrode is larger than that with Cu electrode, which can contribute to the different efficiency of electron transport along the molecular junction between Ag and Cu electrodes. The current work shows the important role for the electrode material in electron transport.

To mitigate the impact of global warming on the environment, many governments, non-profit organizations, and enterprises have formulated relevant standards to assist enterprises in promoting carbon management, and to encourage the design and popularization of low-carbon products. These standards include: PAS 2050, ISO/TS 14067 and so on. Under these initiatives, enterprises try to disclose the carbon and water footprints of the products based on the life cycle. Some enterprises argue and debate that there exists uncertainty of the footprints calculation since the data collection is not systematically. To solve this problem, in this research, the calculation of carbon footprint and water footprint are evaluated with the data quality indicator (DQI) management system. The collected data is evaluated based on the footprint calculation methods. Also the pedigree matrix is constructed as an aide to solve the data uncertainty that included reliability, completeness, times, geography, and technologies differences. Through the DQI, the carbon footprint and water footprint are not only calculated simultaneously, but also correctly. The results could be the reference for products’ environmental improvement.

A pipe-bottle model with a volume of 125 mL was proposed to estimate the permeability of benzene and toluene for the polyvinyl chloride (PVC) water pipes. The concentrations of permeant in pipe-water were directly sampled using the solid phase microextraction (SPME) technique. The permeability coefficients of benzene and toluene were 0.07 and 0.025 μg/cm/hr, respectively, indicating toluene is less permeable through the PVC pipe. Using a transient mass diffusion equation and appropriate initial and boundary conditions, the simulation studies of the concentration profiles of benzene in pipe-water implied that swelling of the PVC pipe wall might have a significant effect on the permeation experiments. The new pipe-bottle model is a less time-consuming and more sensitive means to determine the chemical resistance of polymeric pipes to permeation by organic solvents.

The title complex, {[Cu(phen)(Ts-gly)(H2O)](Ts-gly)}n, where Ts-gly = N-p-Tolylsulfonyl-glycine and phen = 1,10-phenanthroline, was synthesized and its crystal structure was determined by X-ray diffraction analysis. The copper ion is in a slightly distorted square-pyramidal geometry and is coordinated by two N(N1, N2) atoms of 1,10-phenanthroline ligand and one O1 atom of water molecular and one O2 atom of Ts-gly ion, and a weak-coordination O3A atom of adjacent Ts-gly ion. The complex shows a one-dimensional zigzag chain bridged by the weak key role Cu-O3A.

Since its discovery, graphene has been the star material either in scientific studies or potentially technical applications. There are various methods for preparation of graphene films (e.g. mechanical exfoliation, epitaxial growth, molecular assembly, chemical vapour deposition, thermal photocatalysis, and chemical or electrochemical reduction of graphene oxide). In this article, we briefly reviewed the growths of three-dimensional graphene films on metallic and non-metallic substrates using plasma enhanced chemical vapour deposition by emphasising on their growth mechanisms. Since this technique is still in its early stage, the general absence in understanding of the graphene growth processes is thus needed to be clarified. Moreover the utility of plasma enhanced chemical vapour deposition allows synthesis of graphene films at relatively low temperatures and therefore it is possible to directly grow graphene on the substrates that could not survive at high temperatures.

Phthalate esters (PAEs) have been widely added as the plasticizer to increase the flexibility and ductility of polymeric materials. In this study, organic solvents, such as methanol, hexane, ethyl ether and acetone, were used for the direct extraction of plasticizers in neoprene, nitrile, and PVC gloves, under a temperature range of 20-80°C. The results showed that DEHP (Di-2-ethylhexyl phthalate) and DBP (Di-n-butyl phthalate) were analyzed in all three glove samples. The extraction capability of PAEs from the PVC gloves was the highest, while that from the neoprene gloves was the lowest. It was found that the extraction capabilities of DEHP from the glove samples were proportional to Log Kow of the extraction solvents. This result implied that PAEs were more soluble in a non-polar solvent and likely to be extracted from the glove samples. In addition, the amount of extracted PAEs increased with the experimental temperatures. As workers wearing the chemical protective gloves, there is a need to understand the dissolution potential of PAEs in the gloves and to assess the skin exposure of PAEs.

The single molecular conductance of amino acids was measured by a scanning tunneling microscope (STM) break junction. Conductance measurement of alanine gives out two conductance values at 10−1.85 G0 (1095 nS) and 10−3.7 G0 (15.5 nS), while similar conductance values are also observed for aspartic acid and glutamic acid, which have one more carboxylic acid group compared with alanine. This may show that the backbone of NH2–C–COOH is the primary means of electron transport in the molecular junction of aspartic acid and glutamic acid. However, NH2–C–COOH is not the primary means of electron transport in the methionine junction, which may be caused by the strong interaction of the Au–SMe (methyl sulfide) bond for the methionine junction. The current work reveals the important role of the anchoring group in the electron transport in different amino acids junctions.

Clinical trials have provided conflicting results regarding whether epidermal growth factor receptor (EGFR) overexpression predicts poor survival in cervical cancer patients. In this study, we perform a meta-analysis of the association between EGFR expression and survival in cervical cancer patients. We searched clinical studies in the Medline, PubMed, Embase, and Web of Science databases. A total of 22 studies with 2,505 patients were included, and pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated for each study. Heterogeneity was assessed using Higgins I2 to select a Mantel-Haenszel fixed effects model (I2 ≤50%) or a DerSimonian-Laird random effects model (I2 ≥50%). High EGFR levels predicted poor overall survival (OS) (HR: 1.40, 95% CI: 1.10-1.78) and disease-free survival (DFS) (HR: 1.84, 95% CI: 1.51-2.24). Stratified analyses showed that EGFR overexpression was significantly related to poor DFS in patients treated with chemoradiation or surgery. Moreover, the pooled odds ratios (ORs) revealed associations between EGFR expression and clinicopathological features, such as lymph node metastasis (OR: 1.72, 95% CI: 1.23-2.40) and tumor size ≥4 cm (OR: 1.64, 95% CI: 1.20-2.23). This meta-analysis demonstrates that EGFR overexpression is closely associated with reduced survival in patients with cervical cancer. These results may facilitate the individualized management of clinical decisions for anti-EGFR therapies in cervical cancer patients.

In this article, we have investigated the influence of the nitro side-group on the single molecular conductance of pyridine-based molecules by scanning tunneling microscopy break junction. Single molecular conductance of 4,4′-bipyridine (BPY), 3-nitro-4-(pyridin-4-yl)pyridine (BPY-N), and 3-nitro-4-(3-nitropyridin-4-yl)pyridine (BPY-2N) were measured by contact with Au electrodes. For the BPY molecular junction, two sets of conductance were found with values around 10−3.1 G0 (high G) and 10−3.7 G0 (low G). The addition of nitro side-group(s) onto the pyridine ring resulted in lower conductance of 10−3.8 G0 for BPY-N and 10−3.9 G0 for BPY-2N, respectively, which can be attributed to the twist angle of two pyridine rings. Moreover, the steric hindrance of nitro group(s) also affects the contacting configuration of electrode-molecule-electrode. As a consequence, only one set of conductance value was observed for BPY-N and BPY-2N. Our work clearly shows the important role of side-groups on the electron transport of single-molecule junctions.

The heterometallic Ln(III)–Cu(II) coordination polymers [CuLn2(IN)8(H2O)4] n (IN = isonicotinate, Ln = Gd (1), Dy (2), Er(3)) have been synthesized by hydrothermal reactions and characterized by elemental analysis, IR and single crystal X-ray diffraction. The compounds are isomorphous and crystallize in monoclinic space group P21/c, adopting a one-dimensional chain structure with alternately arranged [Ln2(IN)6(H2O)4] and [Cu(IN)2] building blocks bridged by isonicotinates. Temperature-dependent magnetic susceptibility for complex 1 was studied, and a very weak ferromagnetic interaction between metal ions was observed.

In the title compound, C(14)H(13)NO(4)S·0.5C(10)H(8)N(2), the two benzene rings are nearly perpendicular to each other [dihedral angle = 83.21 (10)°]. The bipyridine mol-ecule is centrosymmetric, the mid-point of the C-C bond linking the pyridine rings being located on an inversion center. Inter-molecular N-H⋯O and O-H⋯N hydrogen bonds and weak inter-molecular C-H⋯O hydrogen bonds are present in the crystal structure.

In the title complex, [Cu(C(10)H(12)NO(4)S)(OH)(C(10)H(8)N(2))]·0.5H(2)O, the Cu(II) ion shows a distorted square-pyramidal coordination geometry with two N atoms from the 2,2'-bipyridine ligand and one N and one O atom from the N-tosyl-α-alaninato ligand forming the basis of the coordination polyhedron and another O atom of the hydroxo group acting as the apex of the pyramid. The solvent water mol-ecule is statistically disordered over two positions.

The title complex, [Nd(C6H6NO3S)2(C12H8N2)2(H2O)3]NO3·4H2O, comprises a mononuclear cation, an NO3− anion and two uncoordinated water molecules; the NdIII cation, one coordinated water molecule, and the NO3− anion each lie on a twofold axis of symmetry. The NdIII ion exhibits an NdN4O5 coordination environment comprising two O atoms of two monodentate 4-aminobenzenesulfonato ligands, four N atoms of the bidentate 1,10-phenanthroline ligands, and three water-O atoms. The coordination geometry is based on a tricapped triangular-prismatic arrangement. The components are consolidated into a three-dimensional network via O—H...O, O—H...N and N—H...O hydrogen-bonding interactions

The title compound, [CuEu(2)(C(6)H(4)NO(2))(8)(H(2)O)(4)](n), displays a one-dimensional chain structure. The four-coordinate Cu(II) ion (site symmetry ) adopts a trans-CuN(2)O(2) geometry and is bridged by two carboxyl-ate groups from two isonicotinate ligands. The Eu(III) ion adopts a distorted square-anti-prismatic geometry, being coordinated by four O atoms from bridging carboxyl-ate groups of four isonicotinate ligands, two O atoms from chelating carboxyl-ate groups of one isonicotinate ligand and two O atoms from coordinated water mol-ecules; adjacent Eu(III) ions in the chain are related by inversion. The water mol-ecules interact with the ligands via O-H⋯N hydrogen bonds [O⋯O = 2.782 (3)-2.881 (3) Å], which link the chains into a three-dimensional structure.

The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05). An empirical model, consisting of the molecular weight and the polarizability, was developed to appropriately predict the partition coefficients of organic compounds. The empirical model for estimating the PDMS-gas partition coefficient will contribute to the practical applications of the SPME technique.

In order to maintain ecological environment, protect limited natural resources, promote the quality of life, and advance the eternally usage of all precious resources, we have some good achievement in both industrial circles, government official areas, and academic communities. Since each engineering method will cause different impact, we need to effectively grasp the biological informa- tion for engineers to make the appropriate decisions in choosing the construction system. In the completion time of the project, the eco- logical restoration condition can be an important indexes to determi- nate the successful of the ecological engineering method. In this re- search, we will use GIS, ER Model, Database and Delphi to develop "Ecological Engineering Environment Index Monitoring Management System". In this system, we will record the species, quantity, and appearing timing of all creatures. The referred index, such as gradient, vegetation multiplicity, landforms, etc., that can be used in design period will be stored and can be queried from system to achieve a better construction system. Through the help of this system, we can record all biological information and referred index so the engineering designer can inquire these data to exactly control the related ecological information around the project base. This will reduce the impact of the construction to the only earth we have. We can evaluate the restoration of the creatures to examine the effects of the project. These evaluation data can be used to adjust the design index for future project. We can then effectively protect the earth resources and make the better use of the natural resources.

The construction market has been declined significantly for last few years in Taiwan. In order to survive in such difficulty environment, we have put some efforts on improving construction methods, creating new materials, and some other aspects. However, the most important factor to assure the success for construction companies is to perform construction management practically. We need to control each stage, from bidding, purchasing, and construction, very carefully so we can stay in good competition and maintain good profit.