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The alternate load path method for progressive collapse analysis ignores the cause and mechanism of member failure and its influence on the dynamic effect of the remaining structures. It must assume the location of member failure, which is unsuitable for grid structures with many members. In this paper, by using the double broken line follow-up strengthening model and the proposed VUMAT material constitutive model, taking the member instability and material failure as the member failure criteria and considering the geometric nonlinearity and material nonlinearity, the instantaneous member removal method for deleting the failure member in real time was proposed. On this basis, nonlinear dynamic analysis for a three-layer space truss was used to compare the effects of different member failure criteria on the structural responses, such as the member failure sequence and the occurrence time of the continuous structural collapse. The results show that when considering the instability of members, the initial member failure and the final progressive collapse occur earlier than when using the material failure criterion, which is more similar to the actual situation. Furthermore, the proposed VUMAT material constitutive model can apply to study the progressive collapse behavior of space truss structures. [ABSTRACT FROM AUTHOR]

Low electronic conductivity and large volume variation result in inferior lithium storage performance of ZnO. To overcome these shortcomings of ZnO, herein ZnO nanoparticles are encapsulated in resorcinol–formaldehyde resin-derived hard carbon and then further assembled into a 3-dimensional mesoporous framework structure using a polyvinyl pyrrolidone-derived soft carbon network. The synthesis methods include the polymerization of resorcinol–formaldehyde resin and a polyvinyl pyrrolidone-boiling method. ZnO@dual carbon has af large specific surface area (153.7 m2 g−1) and high porosity. It exhibits excellent cycling performance and high rate capability. After 350 cycles at 500 mA g−1, the ZnO@dual carbon still delivers a discharge capacity of 701 mAh g−1 while the actual discharge capacity of ZnO reaches 950.9 mAh g−1. At 2 A g−1, ZnO@dual carbon delivers the average discharge capacity of 469.6 mAh g−1. The electrochemical performance of ZnO@dual carbon is remarkably superior to those of ZnO@single carbon, pure carbon and pure ZnO nanoparticles, demonstrating the superiority of the dual carbon-assembly structure. This composite structure greatly improves the structural stability of ZnO, enhances its electron conductivity and overall electron transport capacity; which facilitates electrolyte penetration and Li ion diffusion, leading to improved cycling stability and good rate capability. [ABSTRACT FROM AUTHOR]

In this article, we observe the optically pumped lasing from the high-quality nanocrystalline ZnO thin films obtained by thermal oxidation of ZnS thin films, which were grown on SiO[sub 2] substrates by low-pressure-metalorganic chemical vapor deposition technique. The x-ray diffraction (XRD) patterns indicate that high-quality ZnS films possess a preferred (111) orientation. ZnS has a transformation to ZnO at an annealing temperature (T[sub a]) of 500°C, and fully transforms into ZnO at T[sub a] ≥ 700°C from the XRD patterns. The obtained ZnO films possess a polycrystalline hexagonal wurtzite structure. The fifth-order Raman scattering is observed in the films, which indicates that a large deformation energy exists in the lattice. In photoluminescence (PL), spectra, for all the samples with different annealing temperatures, the near-band-edge (NBE) PL peak has a pronounced blueshift with increasing annealing temperature, while the full width at half maximum (FWHM) decreases gradually. We think that emissions of the bound excitons play an important role in NBE PL. A strong PL with a FWHM of 62 meV at 3.30 eV from NBE has been obtained at room temperature for the samples annealed at 900°C. The PL intensity ratio of the ultraviolet emission to the deep-level emission is as high as 98 at room temperature, indicating the high-quality of the nanocrystalline ZnO films. [ABSTRACT FROM AUTHOR]

The full‐length complementary DNA of two genes related to vertebrate albinism, the tyrosinase gene tyr and tyrosinase‐related protein 1 gene tyrp1, were cloned and analysed from normal and albino yellow catfish Tachysurus fulvidraco. The open reading frames (ORF) of tyr and tyrp1 encode putative peptides of 533 and 526 amino acids (amino‐acid), both of which possess two conserved copper binding sites. The homologous identities of deduced amino‐acid sequences showed that both Tyr and Tyrp1 of T. fulvidraco share considerable similarity with that of channel catfish Ictalurus punctatus. Both tyr and tyrp1 were expressed in a wide range of adult tissues. Tyr gene had the highest expression level in the brain of both normal and albino T. fulvidraco. Tyrp1 had the highest expression level in the skin of normal groups, and the fin of albino groups. The messenger (m)RNA expressions of tyr and tyrp1 were detectable at different early developmental stages and varied with embryonic and larval growth. Tyr and tyrp1 mRNA have obvious tissue specificity both in normal and albino T. fulvidraco and higher expression levels were detected in the normal group revealing that tyr and tyrp1 may have an important role in pigmentation. These results will provide useful data for understanding the molecular mechanism of melanin formation and the occurrence of albinism in T. fulvidraco. [ABSTRACT FROM AUTHOR]

Discusses a study which observed magneto-optic recording domains by mathematical morphology. Principles of mathematical morphology; Segmentation and enhancement of recorded domain image; Conclusions.

Asymmetric ZnO:S/ZnO hetero-nanostructures with well-defined morphology were synthesized by a one-step gas phase condensation process. The as-synthesized products were systematically characterized by transmission electron microscopy. Based on observations, a growth mechanism of the complicated hetero-nanostructures is suggested. The facile synthetic route to prepare these ZnO:S/ZnO hetero-nanostructures offers a possibility to satisfy the special needs of optoelectronic applications. The electronic structures of the hetero-nanostructures were investigated by electron energy loss spectroscopy. Both the common features and the differences between the pure ZnO and S-doped ZnO sections are discussed. These features might provide a new test routine for sulfur implantation and might be useful generally in the control, manipulation, transfer, and harvesting of UV light for ZnO. [ABSTRACT FROM AUTHOR]

Background A higher risk of allergic diseases such as rhinitis, asthma and atopic eczema (atopic dermatitis) has been reported for patients with alopecia areata ( AA) compared with the general population, but the significance of this is still largely unclear. Aim To determine whether serum total or specific Ig E play a role in the onset and severity of AA. Methods We tested 461 serum samples from 351 patients with AA and 110 healthy controls ( HC) for total Ig E (t Ig E) and specific Ig E (s Ig E) by Immuno CAP-100 or in vitro test ( IVT). Results The absolute value of t Ig E was higher in patients with AA than in normal controls ( P < 0.001), although the prevalence of raised t Ig E (> 120 IU/mL) detected in patients with AA (29.3%) was similar to that of HC (21.8%). Prevalences of raised s Ig E against various allergens detected by Immuno CAP-100 showed that Dermatophagoides pteronyssinus ( Der p; 31.1%) and Dermatophagoides farinae ( Der f; 29.0%) were the most common allergens. Similar results were found by IVT, with the most common response being against Der p/ Der f (29.0%). However, the prevalences of t Ig E and s Ig E against dust mites ( Der p and Der f) in patients with early-onset AA and severe AA were significantly higher than those with late-onset AA and mild AA ( P = 0.02, P = 0.02 vs. P = 0.03 and P = 0.001, respectively). Notably, the increases in t Ig E and s Ig E were independent of atopy history. Conclusions Allergy to dust mites may have an effect on the immune response in AA, and may contribute to its early onset and severity in patients of Chinese origin. [ABSTRACT FROM AUTHOR]

Nano-structured TiO2particles prepared by hydrothermal method are first immobilized on the surface of silk fiber using tetrabutyl titanate, which is dyed with C.I. Reactive Blue 19. The morphology, crystalline phase, chemical structure, thermal, and optical properties of silk fabric before and after treatment are determined by means of scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric, and diffuse reflectance spectrum techniques. The UV protection, percentage of exhaustion, percentage of fixation, K/S value, and color fastness are investigated. The results indicate that when silk fabric is treated with tetrabutyl titanate aqueous solution at 110 °C for 2 h, pure anatase phase TiO2nanoparticles of size less than 10 nm are synthesized, and then simultaneously grafted onto fiber surface. Compared with the original fabric, the thermal stability of the TiO2-coated fabric changes little. The protection against ultraviolet radiation is distinctly improved. The yellowness and whiteness values change a little. The percentage of exhaustion, fixation and K/S value are reduced to some extent due to the existence of TiO2film. The color fastness to wet rubbing decreases slightly. The K/S value of the TiO2-coated fabric increases after being scrubbed. The color fastness to light of silk fabric after treatment is enhanced. [ABSTRACT FROM PUBLISHER]

The source rocks of 20 oils in Eocene reservoir from Lengdong oil field have been evaluated using geochemical biomarkers. Most of the oil samples have been undergone light to moderate biodegradation and four of these oil samples suffered heavy biodegradation. The oils were originated from low maturity source rocks within early to middle oil window according to the thermal-maturation-dependent biomarker ratios. Source-related biomarkers indicated that the oils originated from carbonate source rock possessed both high plants and algae organic matter input, while high plants' input was dominant in almost all the oils. The source rocks concerning the oils were deposited under anoxic to suboxic (low EH), salinity to hypersaline, and lacustrine environment with deep water. [ABSTRACT FROM AUTHOR]

The article presents an investigation into the mechanism by which actuator dynamic stiffness influences missile fin flutter. The actuator dynamic stiffness was modified for the development of a method for improving the critical flutter velocity. It discusses two types of flutter-analysis methods for a control fin.

It is prevailingly thought that estrogen signaling is not involved in development of estrogen receptor (ER)-negative breast cancer. However, there is evidence indicating that ovariectomy prevents the development of both ER-positive and -negative breast cancer, suggesting that estrogen signaling is involved in the development of ER-negative breast cancer. Previously, our laboratory cloned a variant of ER-α, ER-α36, and found that ER-α36 mediated nongenomic estrogen signaling and is highly expressed in ER-negative breast cancer cells. In this study, we found that ER-α36 was highly expressed in 10/12 cases of triple-negative breast cancer. We investigated the role of mitogenic estrogen signaling mediated by ER-α36 in malignant growth of triple-negative breast cancer MDA-MB-231 and MDA-MB-436 cells that express high levels of ER-α36 and found that these cells strongly responded to mitogenic estrogen signaling both in vitro and in vivo. Knockdown of ER-α36 expression in these cells using the small hairpin RNA method diminished their responsiveness to estrogen. ER-α36 physically interacted with the EGFR/Src/Shc complex and mediated estrogen-induced phosphorylation of epidermal growth factor receptor (EGFR) and Src. EGFR signaling activated ER-α36 transcription through an AP1 site in the ER-α36 promoter, and ER-α36 expression was able to stabilize EGFR protein. Our results, thus demonstrated that ER-α36 mediates nongenomic estrogen signaling through the EGFR/Src/ERK signaling pathway in ER-negative breast cancer cells and suggested that a subset of ER-negative breast tumors that expresses ER-α36, retains responsiveness to mitogenic estrogen signaling. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop new pH sensors that can be used to test and monitor hydrogen ion activity in hydrothermal conditions. A Zr/ZrO2 oxidation electrode is fabricated for in situ pH measurement of high-temperature aqueous solutions. This sensor responds rapidly and precisely to pH over a wide range of temperature and pressure. The Zr/ZrO2 electrode was made by oxidizing zirconium metal wire with Na2CO3 melt, which produced a thin film of ZrO2 on its surface. Thus, an oxidation-reduction electrode was produced. The Zr/ZrO2 electrode has a good electrochemical stability over a wide range of pH in high-temperature aqueous solutions when used with a Ag/AgCl reference electrode. Measurements of the Zr/ZrO2 sensor potential against a Ag/AgCl reference electrode is shown to vary linearly with pH between temperatures 20 and 200 °C. The slope of the potential versus pH at high temperature is slightly below the theoretical value indicated by the Nernst equation; such deviation is attributed to the fact that the sensor is not strictly at equilibrium with the solution to be tested in a short period of time. The Zr/ZrO2 sensor can be calibrated over the conditions that exist in the natural deep-seawater. Our studies showed that the Zr/ZrO2 electrode is a suitable pH sensor for the hydrothermal systems at midocean ridge or other geothermal systems with the high-temperature environment. Yttria-stabilized zirconia sensors have also been used to investigate the pH of hydrothermal fluids in hot springs vents at midocean ridge. These sensors, however, are not sensitive below 200 °C. Zr/ZrO2 sensors have wider temperature range and can be severed as good alternative sensors for measuring the pH of hydrothermal fluids. [ABSTRACT FROM AUTHOR]

Melt of NaCO3 can favor oxidation of Zr to form ZrO2 thin film on Zr surface, which is used to make Zr/ZrO2 oxidation/reduction electrode of pH sensor for testing elevated temperature aqueous solutions. Using SEM, EPMA, XPS, EXAFS and HRTEM, we found that ZrO2 film is tightness and solid with 20 μm thickness composed by nanometer-sized monoclinic crystals. Zr/ZrO2 interface is characterized of zoning structure according to topography and chemical composition in five zones: oxygen-rich ZrO2, ZrO2, oxygen-rich Zr metal, oxygen-bearing Zr and Zr from outmost to center. Melt oxidation process of Zr involved oxidation time, air and temperature. The air is important effect on structural and electrochemical properties of ZrO2 thin film for making elevate temperature electrochemical sensor. If oxygen air largely presented in carbonate melting process, ZrO2 thin film is not tightness and not for oxidation/reduction electrode. [ABSTRACT FROM AUTHOR]

Based on apatite fission track ages (FTA) of 41 samples collected from a south–north transect of the eastern Kunlun mountains, Qinghai-Tibet Plateau, China, this paper shows that (1) the FTA in different blocks increases with the distance from the South-Kunlun fault and Mid-Kunlun faults, respectively, indicating the control of the main faults on the tectonic evolution of this region; and (2) the thermal histories are characterized by slow cooling from ∼160°C to ∼80°C at ∼240 to ∼20 Ma, followed by rather rapid cooling to surface temperatures. [Copyright &y& Elsevier]

The resistive switching effect of the SrTiO3:Nb (0.05wt %, 0.5 wt %, and 1 wt % Nb) single crystals contact with Ag and Pt, respectively, was studied by in situ monitoring the voltage drop (Vs) across the samples. For Ag/SrTiO3:Nb junction, the response time is as short as 5 ns, which is two orders of magnitude short than that of the Pt/SrTiO3:Nb junction. The effect of metal electrodes on the response time has been discussed, which is related to the barrier height of the junction. [ABSTRACT FROM AUTHOR]

Well-aligned Ga-doped N-rich SiOxNy bundles were synthesized on Si substrates by chemical vapor deposition. According to the x-ray photoelectron spectroscopy spectra of the Si 2p3/2 region, the relative shifts of N 1s and chemical stabilities of all the possible tetrahedrons, the most probable four tetrahedral phases in the bundles are Si–N4, Si–N3O, Si–O3N, and Si–O4, corresponding to bonding units of Si3N4, Si2ON2, Si6O9N2, and SiO2. Elemental mappings, by using electron energy loss spectroscopy, confirm that elements Si, O, and N are homogeneously distributed. An intense ultraviolet light emission is observed by using vacuum ultraviolet synchrotron radiation as an excitation light source. [ABSTRACT FROM AUTHOR]

Photoluminescence of Ag-doped ZnSe nanowires synthesized by metalorganic chemical vapor deposition is investigated in the temperature range from 10 to 300 K. Ag impurities were introduced into the ZnSe nanowires during the growing process. Some dominating Ag-related centers are found. Especially, the strong zero-phonon bound exciton luminescence with energy near 2.747 eV is attributed to a neutral AgZn acceptor complex. This is because the emission peak at the same energy is observed only in the photoluminescence spectrum of the Ag-doped bulk ZnSe. A new luminescence peak at 2.842 eV is attributed to the recombination of excitons bound to ionized acceptors (I2h) in the hexagonal phase of ZnSe nanowires. The physical origins of the emissions are briefly discussed. [ABSTRACT FROM AUTHOR]

ZnSe nanoribbons have been synthesized using sputter-coated gold films as catalysts via metalorganic chemical vapor deposition on Si (100) substrates. Both x-ray and selected area electron diffractions determine that they have the zinc-blende structure. High-resolution transmission electron microscopic investigations show that their structure is highly ordered and contains coherent twin lamellae near one edge but is essentially free of dislocations. Photoluminescence studies at 10 K show that sharp excitonic peaks dominate their spectra, reflecting their high purity and nearly perfect stoichiometry. New excitonic peaks are observed in the nanoribbons and their possible origins are discussed. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The structural evolution and stratigraphic architecture of the Southern Lufeng Depression in the Pearl River Mouth Basin, South China Sea show two second-order sequences (SSQ1 and SSQ2) and nine third-order sequences (WSQ1-5 and ESQ1-4) within the Eocene rift-related successions. Based on integrated interpretations of seismic reflections, well logs and core data, five distinct tectono-stratigraphic patterns are identified: (1) the initial synrift-I sequence (WSQ1) of low tectonic subsidence, overfilled by alluvial fan or fan-delta deposits and volcanic deposits, with no clear systems tracts; (2) the climax synrift-I sequences (WSQ2–4) developed in response to rapid tectonic subsidence, generally consisting of a low-stand systems tract (LST), transgressive systems tract (TST) and high-stand systems tract (HST); (3) the late synrift-I sequence (WSQ5) characterised by a decreased tectonic subsidence rate, dominated by braided delta, deep and shallow lacustrine sediments, mainly constructed by TST and HST; (4) the early synrift-II sequences (ESQ1–2) rapidly filled by braided deltaic sandstone and mainly composed of TST and HST with less common LST units; and (5) the late synrift-II sequences (ESQ3–4), which are totally filled by braided deltaic system in a shallow-water lake setting, presenting typical imbricate clinoforms or sub-parallel seismic configurations, consisting of only TST and HST components. During the climax stage of synrift-I development, the depositional setting changed from a prominent shallow lake (WSQ2) to a deep-lucustrine with turbiditic deposits (WSQ3) and finally dominated by mostly braided deltaic-shallow lacustrine deposits (WSQ4); the HST occupies an increasing proportion from early to late. Furthermore, the stratigraphic patterns, especially LST units of the climax synrift-I stage, are significantly influenced by topographic variations and slope-break belt types in the hanging dip-slope. This study reveals that the spatial and temporal evolution of lacustrine depositional and stratigraphic patterns were significantly controlled by the interplay of tectonic subsidence and sediment supply, and provides a fundamental basis for predicting the favourable reservoirs and geometry of source rocks related to the general variability of Eocene rift-related tectonic subsidence in the Southern Lufeng Depression of the Pearl River Mouth Basin. Furthermore, the topographic responses of differential active fault-stepped patterns associated with magma intrusions, highlight the variability of relevant sequence architectures in the hanging dip-slope in lacustrine rift basins. [ABSTRACT FROM AUTHOR]

Ghrelin, the endogenous ligand for the growth hormone secretagogue receptor (GHS-R), is produced by multiple cell types and affects feeding behavior, metabolic regulation, and energy balance. In the mammalian pancreas, the types of endocrine cells that are immunoreactive to ghrelin vary. However, little was known about its distribution and developmental changes in the pancreas of African ostrich chicks (Struthio camelus). In the present study, the distribution, morphological characteristics, and developmental changes of ghrelin-immunopositive (ghrelin-ip) cells in the pancreas of African ostrich chicks were investigated using immunohistochemistry. Ghrelin-ip cells were found in both the pancreatic islets and acinar cell regions. The greatest number of ghrelin-ip cells were found in the pancreatic islets, and were primarily observed at the periphery of the islets; some ghrelin-ip cells were also located in the central portion of the pancreatic islets. Interestingly, from postnatal d 1 to d 90, there was a steady decrease in the number of ghrelinip cells in the pancreatic islets and acinar cell regions. These results clearly demonstrated that ghrelin-ip cells exist and decreased with age in the African ostrich pancreas from postnatal d 1 to d90. Thus, these findings indicated that ghrelin may be involved in the development of the pancreas in the African ostrich. [ABSTRACT FROM AUTHOR]

This study investigates the developmental morphology changes on the proventriculus and gizzard of African ostrich chicks using gross anatomy, and light and transmission electronic microscopy. The body weight; the weight of the proventriculus and gizzard; the thickness of simple tubular glands, muscularis mucosae, compound tubular glands, and muscular layer of the proventriculus; and the thickness of the gizzard glands and muscularis mucosae were measured on postnatal d one, 45, 90, and 334. Under transmission electronic microscopy, the oxynticopeptic cells, mucous cells, and endocrine cells were observed in the proventriculus on postnatal d one, 45, and 90. Our results revealed that the weights of the proventriculus and gizzard (relative to the body weight) both peaked on d 90, respectively, and declined thereafter. The thicknesses of the simple tubular glands, muscularis mucosae, compound tubular glands, muscular layer of the proventriculus, and gizzard glands increased with increasing bird age. However, the thickness of the muscularis mucosae in the gizzard peaked on d 90 and gradually decreased thereafter. The result of transmission electron microscopy revealed that the glands in the submucosa layer of the proventriculus did not differ from other cell types, aside from an increase in cell diameter and an increase in cytoplasmic content. A significant increase in the number of mitochondria and smooth endoplasmic reticulum was noted, as well as an in granules secreted by endocrine cells. Therefore, to improve brood rates of reared African ostrich chicks, feed management ought to be enhanced between postnatal d one and day 90. [ABSTRACT FROM AUTHOR]

Meat duck deep litter is considered to be an ideal environment for the evolution of bacterial antibiotic resistance if it is under poor management. The aim of this study was to characterize the accumulation of antibiotics and heavy metals in the deep litter and their role in the persistence of antibiotic resistance of Escherichia coli, and evaluate the service life of the deep litter. Samples were collected from initial, middle, and final stages of deep litter within 3 barns (zero, 4, and 8 rounds of meat duck fattening, d 34) and 9 flocks, with known consumption of antibiotics in the controlled trail. The feed and litter levels of consumed antibiotics and heavy metals were measured. E. coli (n = 147) was isolated and typed by Eric-PCR and the phylogenetic grouping technique, while minimal inhibitory concentrations of antibiotics and heavy metals were measured. This study confirmed the continuous accumulation of doxycycline and many heavy metals in the deep litter. The population of resistant certain bacteria to doxycycline (16 mg/L, 100 mg/L) or ofloxacin (8 g/mL, 50 g/mL) increased in the used deep litter (rounds 4 and 8). E. coli isolated from the 3 stages of sampling were highly resistant to ampicillin, tetracycline, florfenicol, and doxycycline. Increased resistance to ceftiofur, enrofloxacin, ofloxacin, and gentamicin were seen in the isolates from the final stage of deep litter. In addition, the percentage of isolates tolerant to zinc, copper, and cadmium and the numbers of Group-B2 isolates all increased in the used deep litter, and the isolates of each stage belonged predominantly to commensal groups. The antibiotic resistance of isolates with identical Eric-PCR patterns had improved from round 4 to 8, and differences still existed in the resistance profiles of isolates with identical Eric-PCR patterns from different barns of the same round. This study concluded that deep litter could be suitable for the evolution of bacterial antibiotic-resistance under conditions of continuous usage or accumulation of antibiotics and heavy metals without proper management. [ABSTRACT FROM AUTHOR]

Sheath blight (SB), caused by Rhizoctonia solani, is one of the most destructive rice diseases worldwide. It has been difficult to generate SBresistant varieties through conventional breeding because of the quantitative nature of rice resistance to SB. In this study, we found that overexpression of the OsOSM1 gene, encoding an osmotin protein belonging to the pathogenesis-related protein 5 family, is able to improve rice resistance to SB in field tests. Although there are two osmotin genes in rice, OsOSM1 is the one mainly expressed in leaf sheath at the booting stage, coinciding with the critical stage of SB development in the field. In addition, OsOSM1 expression is strongly induced by R. solani in SB-resistant rice variety YSBR1 but not in susceptible varieties, suggesting its involvement in SB resistance. Overexpression of OsOSM1 (OsOSM1ox) in susceptible variety Xudao 3 significantly increases resistance to SB in transgenic rice. The OsOSM1 mRNA levels in different transgenic lines are found to be positively correlated with their SB resistance levels. Intriguingly, although extremely high levels of OsOSM1 were detrimental to rice development, appropriately elevated levels of OsSOM1 were obtained that enhanced rice SB resistance without affecting rice development or grain yield. The OsSOM1 protein is localized on plasma membrane. OsOSM1 is upregulated by jasmonic acid (JA); furthermore, JA-responsive marker genes are induced in OsOSM1ox lines. These results suggest that the activation of JA signaling pathway may account for the increased resistance in transgenic OsOSM1ox lines. Taken together, our results demonstrate that OsOSM1 plays an important role in defense against rice SB disease and provides a new target for engineering resistance to SB. [ABSTRACT FROM AUTHOR]

Cobalt coordination polymer [Co(btec)0.5(3-bpcb)]n (H4btec is benzene-1,2,4,5-tetracarboxylic acid, 3-bpcb is N,N '-bis(3-pyridinecarboxamide)-1,4-benzene) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The polymer crystallizes in the triclinic sp. gr. P with unit cell parameters a = 7.5989(3) Å, b = 9.4978(5) Å, c = 14.7638(7) Å, α = 93.116(2)°, β = 110.020(2)°, γ = 989.17(8)°, Z = 2. Cobalt(II) ions have octahedral coordination, linking different btec4− anions to form a two-dimensional layer, and 2D layers are associated into 3D networks via L-ligands. [ABSTRACT FROM AUTHOR]

In order to improve the dye depth of TiO2-modified wool fibers, chitosan is incorporated with tetrabutyl titanate in preparing the nanosized TiO2particles, which are loaded on the surfaces of wool fibers, during hydrothermal process. The TiO2coated wool fibers are subsequently dyed with Lansol Blue 3G. The structural changes of wool fibers before and after treatments are characterized by several techniques, such as field emission scanning electron microscope, energy-dispersive X-ray, transmission electron microscope, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermal gravimetric analysis, and diffuse reflectance spectrum. The properties of tensile, antibacterial activity, yellowness and whiteness indices, dye uptake,K/Svalue, color fastness to washing, rubbing, and artificial light are also compared. It is found that the as-prepared TiO2particles with pure anatase phase are easy to agglomerate because of the introduction of chitosan. Meanwhile, the aggregated particles are deposited on the surface of wool fibers via a simple hydrothermal route. Compared with the original wool fibers, the thermal behaviors of the TiO2coated wool fibers change slightly. The performances of UV protection, antibacterial activity, dyeing depth, and color fastness to wet rubbing and artificial light are improved to some degree. However, the tensile properties of wool fibers decrease but not too much. [ABSTRACT FROM PUBLISHER]

Background: China has had about 1.2 billion mobile-phone users, and this number continues to grow. However, mobile-health services (mHealth) are currently in the initial stage, and have not yet prevailed in China. Additionally, the prevalence of Parkinson's disease (PD) in China is 1700/100,000 (≥65 years). Indeed, these PD patients would benefit from mHealth to manage their disease. Therefore, we designed a study to determine attitudes toward smartphone applications (apps) for chronic condition self-management, and to discover the practicality of these apps among PD patients in China.Methods: We selected 204 participants with PD between 52 and 87 years old and surveyed their attitudes concerning the use of smartphone apps for chronic condition management via questionnaires.Results: Among the participants, 65.19% had smartphones. Among these smartphone users, 82.84% expressed a preference for using apps for PD management. This group tended to be younger and more frequent web users with higher education and better medication compliance, and they tended to have a longer PD course and worse conditions (P < 0.001, P = 0.001, P < 0.001, P = 0.041, P < 0.001, P = 0.013). Additionally, the willingness to apply apps for PD self-management was positively related to education (P < 0.001) and negatively related to age and PD course (P = 0.017, P < 0.001).Conclusion: In China, patients with PD have a generally positive attitude towards self-management through smartphone apps. Consequently, improving the coverage of smartphones with practical and handy apps is a promising strategy for PD self-management. [ABSTRACT FROM AUTHOR]

Objectives To understand the current status of intellectually disabled children and the prevalence of intellectual disability (ID) in children aged 0∼6 years and its risk factors, and to provide scientific evidence to formulate relevant policies for helping intellectually disabled children. Methods Multiphase, stratified, unequal proportional and cluster sampling was adopted to investigate 60 124 children aged 0∼6 years. All the children investigated were screened for ID using the Denver Developmental Screening Test, and those with positive screening test would be further diagnosed by varied specialists using the Gesell Developmental Inventory. Results In total, 560 of 60 124 children were diagnosed as intellectually disabled with an overall prevalence of 0.93%. Prevalence of ID was highest in children living in medium-developed areas with a prevalence of 1.20%, higher than in those living in developed areas (0.75%) and in underdeveloped areas (0.84%). It was higher in rural areas (1.03%) than in urban areas (0.83%), and higher in boys (1.01%) than in girls (0.84%). Prevalence of ID increased with the age of children and decreased with the educational level of their parents. Conclusions The study suggested that ID is still prevalent in the children of China, and rehabilitation for them is lagging behind current needs. Early prevention of ID in children and pre-school education for them should be strengthened. [ABSTRACT FROM AUTHOR]

Gold as a hydrogen-sensing electrode for in situ measurement of dissolved H2 in aqueous solutions under extreme conditions is reported. The dissolved H2 sensor, constructed with a Au-based sensing element and coupled with a YSZ/HgO/Hg electrode, is well suited for determining dissolved H2 concentrations of aqueous fluids at elevated temperatures and pressures. The Au electrode is made of Au wire mounted in a quartz bar, which can be pressurized and heated in the high-pressure and -temperature conditions. The Au-YSZ sensor has been tested for its potential response to the concentrations of dissolved H2 in fluids by using a flow-through reactor at high temperatures up to 400 °C and pressures to 38 MPa. Good sensitivity and linear response between the hydrogen concentrations in the fluids and the H2 sensor potentials are reported for hydrogen gas in the concentration range of 0.1-0.001 M H2 in aqueous fluids at temperatures up to 340 °C and 30 MPa. Nernstian response of the cell potential to dissolved H2 in fluids was determined at 340 °C and 30 MPa, described as follows: ΔE =0.9444 + 0.0603 log mH2 The experimental results indicate that the Au-YSZ/HgO/Hg cell can be used to measure the solubility of H2 in aqueous fluid at temperatures and pressures near to the critical state of water. Thus, this type of Au hydrogen sensor could be easily used for in situ measurement of H2 in hydrothermal fluids in a high-pressure vessel, or at midocean ridge, due to its structure of compression resistance. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the sensitivity of downstream baroclinic development to a tropical cyclone's (TC's) intensity and its initial location relative to the upstream trough during the extratropical transition (ET) of Typhoon Malakas were examined. The downstream development intensity at the mid-latitudes was mainly determined by two factors under the effect of ET, i.e. the strength of transporting low potential vorticity (PV) air downstream by the TC outflow and the strength of the PV gradient being disturbed in the mid-latitude jet. The intensified TC had a stronger upper-level outflow, and the intensified circulations associated with it could disturb the mid-latitude PV gradient more strongly. Therefore, downstream development intensified, i.e. the trough-ridge became more pronounced, and the jet became stronger. Downstream development seemed to be more sensitive to the TC location than its intensity. The TC, being closer to the trough, interacted with the mid-latitude flow more strongly because the trough advanced and strengthened the process that the TC outflow transported low PV air to the mid-latitudes in this situation. Moreover, the TC disturbed the PV gradient earlier and more strongly. The two effects intensified the downstream development. If the TC were weakened or moved away from the upstream trough, the outcome would be the opposite. [ABSTRACT FROM AUTHOR]

Local chemical states and thermal stabilities of N dopants in ZnO:N film are investigated by temperature-dependent x-ray photoelectron spectroscopy. Different types of N local states are detected, including N2 molecules occupying O sites [(N2)O], –NO species, substitutional N atoms in O- and N-rich local environments (α- and β-NO). Compared to the β-NO, the α-NO shows a better thermal stability up to 723 K. However, the transformation from α-NO acceptor to undesirable (N2)O donor occurs above 743 K. The variation of N local states also affects Zn and O binding energies. Photoluminescence studies indicate the shallow acceptor nature of α-NO. [ABSTRACT FROM AUTHOR]

InN nanowires and faceted hexagonal InN nanotubes are synthesized by catalyst-free chemical vapor deposition at different temperatures. Both have the single crystalline wurtzite structure and grow along the c axis. Different growth dynamics are suggested for the difference in morphology. Observations of phonon-plasmon coupled modes in their Raman scattering suggest of high electron concentrations. Absorption edges in their optical spectra have energies slightly higher than 1 eV, showing blueshifts from the fundamental band gap of ∼0.7 eV, recently observed in epitaxial films. The shifts are argued to be the result of the Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

Wurtzite structured AlGaN alloy nanowires over the entire compositional range have been grown on silicon (100) substrates by chemical vapor deposition using NH3 vapor and a mixture of Al powders and molten Ga droplets. The morphology, structure, and compositions were characterized by scanning and transmission electron microscopies, energy dispersive x-ray analysis, and micro-Raman scattering. The nanowires grow along the <0001> direction and remain as a single phase alloy, despite their small diameter. At comparable diameters, previous studies had shown that AlGaN nanowires would have spontaneously phase separated. The growth of the nanowires is suggested as via a self-catalytic vapor-liquid-solid mechanism. [ABSTRACT FROM AUTHOR]

Objective:This study aimed to define the characteristics and use of ocular and cervical vestibular evoked myogenic potentials for evaluating paediatric cochlear implant candidates.Methods:Ocular and cervical vestibular evoked myogenic potentials of 34 paediatric cochlear implant candidates were analysed. All patients also underwent a routine audiological examination, including computed tomography.Results:In all, 27 patients with normal inner-ear structures had absent or impaired vestibular evoked myogenic potential responses. In paediatric candidates with inner-ear malformations, ocular and cervical vestibular evoked myogenic potentials had lower thresholds and higher amplitudes. Vestibular evoked myogenic potential responses in this cohort were classified into three groups. There was significant concordance between vestibular evoked myogenic potentials and temporal bone computed tomography findings.Conclusion:Ocular and cervical vestibular evoked myogenic potential waveforms were different in paediatric candidates with normal and abnormal inner-ear structures. Therefore, vestibular evoked myogenic potential responses can indicate temporal bone structure. [ABSTRACT FROM PUBLISHER]

The ZnCo2O4 nanorods and nanosheets were grown on nickel foam by a facile and effective hydrothermal method, respectively. The effect of the morphologies of the nanostructures on electrochemical performance was investigated. Importantly, ZnCo2O4 nanorod electrodes with a high specific surface area exhibited a higher specific capacitance of 2457.4 F g at 2 A g and remarkable cycling stability with capacitance retention of 97.7% after 1000 cycles, which are superior to those of ZnCo2O4 nanosheet electrodes. Such a result is well explained. The investigation on the electrochemical properties of these two nanostructures as electrodes confirmed that the morphology of active materials has an important impact on electrochemical properties. ZnCo2O4 nanosheets and nanorods were successfully grown on foam substrate. ZnCo2O4 nanorod electrodes with a high specific surface area exhibited a higher specific capacitance and good cycling stability. [ABSTRACT FROM AUTHOR]

One-dimensional ZnO-core-ZnSe-shell heterostructures with different ratios of the two components were fabricated via a two-step chemical vapor deposition process at different temperatures of the substrates. The scanning electron microscopy images show that numerous ZnSe nanoparticles with different sizes are uniformly distributed on the surface of ZnO nanobelts. The X-ray diffraction patterns confirm that the heterostructures are composed of wurtzite ZnO and cubic ZnSe. The intensity ratios of visible emission to ultraviolet emission (from 0.15 to 14.50) are tuned by the change in the components due to the type-II energy band alignment structure. The photoluminescence mechanism of the ZnO-ZnSe heterostructures is proposed. In addition, the absorption of ZnO-ZnSe heterostructures extends from the ultraviolet region to the visible region, compared with the pure ZnO. The ZnO-ZnSe heterostructures with type-II energy band alignment show a high photocatalytic activity. [ABSTRACT FROM AUTHOR]

In this paper, ZnO nanobelts were synthesized by chemical vapor deposition. And then Au nanoparticles were sputtered on the ZnO nanobelts. Enhancement of the near-band edge emission of Au/ZnO composite nanobelts was observed from photoluminescence measurement due to the coupling between the defect emission from ZnO and surface plasmons of Au nanoparticles, compared to bare ZnO nanobelts. The coupled energy could be transferred into free space photons when the interface is sufficiently rough to scatter the surface plasmons. The enhancement ratio of the near-band edge emission of Au/ZnO is 11-fold higher than that of bare ZnO. The enhancement mechanism was proposed based on scattering and absorption by Au nanoparticles. [ABSTRACT FROM AUTHOR]

A new method for the preparation of Fe2O3 nanoparticle/SiO2 microsphere composites is described, in which fine alpha-Fe2O3 nanocrystals were prepared by forced hydrolysis of FeCl3 aqueous solution. The structure and optical spectra of these alpha-Fe2O3 nanocrystals have been studied. Their visible optical absorption can be enhanced by their adsorptions on the surface of SiO2 microspheres and thereafter simple packing of these microspheres to the aggregated structures. The size-dependent photogenerated surface photovoltage spectra (SPS) of these composites were studied, and quantum confinement effects of the SPS properties were observed. The transport of photoinduced charges between nanocrystals with intrinsic electronic nature of confined states accounts for this phenomenon. These results are helpful in understanding the relationship among d−d transition and charge-transfer transition in transition metal oxides and find applications in photovoltaic devices. [ABSTRACT FROM AUTHOR]

Electrically pumped near-ultraviolet lasing was achieved in a metal/insulator/semiconductor laser diode based on ZnO/MgO core/shell nanowires. The nanowire diode shows higher emission intensity at relatively low operating current density compared with the planar device. The improved efficiency is attributed to enhanced exciton oscillator strength and superior carrier transport properties of single-crystalline ZnO nanowires, and effective surface passivation by MgO coating. Random laser action was confirmed by the calculation of quality factor and the real-time changes of lasing spectra. The results reveal that the MgO coating serves as electron blocking, hole supplying and surface passivation layer for the nanowire heterostructure. [ABSTRACT FROM AUTHOR]

GaN nanorods with a wurtzite/zinc-blende (WZ/ZB) heterostructure are synthesized by chemical vapor deposition. They have a triangular cross section and grow along the WZ [formula] direction. The WZ and ZB phases appear alternately along the nanorod’s transverse direction, forming a type-II superlattice structure. Two ultraviolet emission peaks dominate the photoluminescence spectra of the GaN nanorods. One originates from excitonic transitions within the WZ regions. The other shows an anomalous “S-shaped” energy shift with increasing temperature, and is attributed to radiative recombinations of carriers localized at potential fluctuations in ZB regions. The carrier localization also results in high luminescent efficiency of the GaN nanorods. [ABSTRACT FROM AUTHOR]