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Using a double-side fabrication method, a stack of intrinsic Josephson junctions plus a bow-tie antenna and chokes were made in a slice 200 nm thick and singled out from inside a bulk Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8+x] single crystal. The junctions in the fabricated stack were very uniform, and the number of junctions involved was rather controllable. Potentially it would be possible to use this method to fabricate integrated circuits based on intrinsic Josephson junctions in high T[sub C] superconductors. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

ESCULENTOSIDE A (EsA) is a saponin isolated from the roots of Phytolacca esculenta . Previous experiments have shown that it has strong antiinflammatory effects. To investigate the mechanism of anti-inflammatory effects of esculentoside A (EsA),[3H] arachidonic acid (AA) prelabelled murine macrophage and radioimmunoassay were used to test the effect of EsA on the total release of AA and prostaglandin E2 in culture supernatants. The results showed that EsA had no significant effect on the total release of AA from murine macrophages. EsA (2.5-10 mu mol/l), from unstimulated murine peritoneal macrophages and rabbit synovial cells, could decrease the production of prostaglandin E2. In A23187 and LPS-treated macrophages and synovial cells, EsA (10 mu mol/l) could significantly decrease the prostaglandin E2 production. These results confirmed that EsA exerted an inhibitory effect on prostaglandin E2 production from murine macrophages and rabbit synovial cells. [ABSTRACT FROM AUTHOR]

We studied the effects of soil pH (3.29, 4.74 and 5.32) on nitrogen uptake and its use efficiency by tea bush. The results showed that with the increase of soil pH value (3.29 ~ 5.32), the nitrogen utilization efficiency of tea bushes increased from 94.28 % to 461.14 %, the nitrogen absorption efficiency increased from 1.05 % to 3.95 % and the nitrogen physiological utilization efficiency increased from 89.79 % to 116.74 %. Besides with the increase of soil pH, the activity of spoil enzymes (Urease, protease, asparaginase, N-acetamide glucose ribosidase) in tea rhizosphere soil was significantly increased, while, that of nitrate reductase and nitrite reductase was decreased significantly. With the increase of soil pH, the expression of nifH gene in tea rhizosphere soil increase significantly, while expression of amoA-AOA, amoA-AOB, nirK, nirS, narG and nosZ gene was decreased. Correlation analysis showed that pH value in tea rhizosphere soil was significantly and positively correlated with nitrogen utilization efficiency, nitrogen uptake efficiency, nitrogen physiological utilization efficiency, urease activity, protease activity, asparaginase activity, N-acetamide glucose ribosidase activity and the expression of nifH gene. Correlation analysis was negatively correlated with nitrate reductase activity, nitrite reductase activity and the expression of amoA-AOA, amoA-AOB, nirK, nirS, narG and nosZ gene. The results indicated that soil acidity significantly affected the ability of soil nitrogen conversion and nitrogen absorption and utilization ability of tea bushes. [ABSTRACT FROM AUTHOR]

FePt/B4C multilayer composite films have been prepared by magnetron sputtering and subsequent annealing in vacuum. It was found that the B4C layers effectively serve as spacers to separate the FePt layers, enhancing (001) orientation of FePt alloy. Our results show that highly (001) oriented [Fe45Pt55(8 nm)/B4C (4 nm)]3 film with satisfactory perpendicular coercivity (4.75 kOe) has significant potential as a perpendicular recording medium. [ABSTRACT FROM AUTHOR]

We screened the fermentation broth of fungi from the rhizosphere soil of passion fruit (Passiflora edulis Sims.) for their herbicidal potential in bioassays and Pot culture. The potent herbicidal compounds of the fungi fermentation broth were evaluated by bioassay and pot test. The candidate substances in the fungi fermentation broth were analysed and identified. Nine fungi (No. 1, 2, 3, 4, 5, 6, 7, 8 and 9) were isolated from the rhizosphere soil of passion fruit using the plate dilution coating method. In Petriplate Bioassay, the fermentation broth of newly identified fungus Aspergillus sydowi 'FJFAFU01' drastically inhibited the growth of lettuce (Lactuca sativa) and barnyard grass (Echinochloa crus-galli). In Pot Culture, 50-times diluted fermentation broth inhibited the barnyard grass height by 42.73%. The HPLC and GC-MS analysis showed that the fermentation broth contained higher contents of nitrogenous compounds and oxygen compounds, including phenolic acids, terpenoids, flavonoids and alkaloids. The Aspergillus sydowi FJFAFU01 screened from the rhizosphere soil of passion fruit contained phenolic acids, terpenoids, flavonoids and alkaloids, these inhibited the growth of barnyard grass. Thus Aspergillus sydowi 'FJFAFU01' may be developed as potential mycoherbicide. [ABSTRACT FROM AUTHOR]

We studied the effects of soil nitrogen and pH in tea plantation soil on tea tree yield and quality in 90-tea plantations in Anxi county, Fujian province, China. The tea tree rhizosphere soil samples were collected for soil pH, ammonium nitrogen and nitrate nitrogen content from 90-tea plantations. The yield of tea tree and the contents of tea polyphenols, theanine and caffeine in tea leaves increased with the increase in soil pH. Secondly, as the soil pH increased, the content of ammonium nitrogen and the ratio of ammonium nitrogen to nitrate nitrogen in tea tree rhizosphere soil also increased, but the content of nitrate nitrogen decreased. Further the yield of tea tree and the contents of tea polyphenols, theanine and caffeine increased, with the increase in ratio of ammonium nitrogen to nitrate nitrogen in the soil. The pH of tea plantation soil was significantly positively correlated with the tea tree yield and quality, and the content of soil ammonium nitrogen, but negatively correlated with nitrate content in soil. This study provides basis for the scientific and rational use of nitrogenous fertilizers in tea plantations. [ABSTRACT FROM AUTHOR]

Objective and design: Cisplatin-based chemotherapy has been widely used in the perioperative period of cancer surgery, which exacerbates the risk of renal injury. In this study, we examined whether dexmedetomidine (DEX), a commonly used anesthetic adjuvant, shows a protective effect against cisplatin-induced acute kidney injury. Materials: Acute kidney injury in mice was induced by cisplatin. Treatments: Mice were administered with DEX 25 μg/kg or atipamezole 250 μg/kg (once a day, for 3 days) after cisplatin treatment. Methods: The renal function and tubular damage score were evaluated at 72 h following cisplatin administration. Apoptotic tubular cells were detected by TUNEL assay. Caspase-3, p53, Bax, F4/80 macrophages, CD3 T cells, and NF-κB were examined by immunohistochemistry staining or Western blot. Tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein (MCP)-1 in kidney were measured using real-time polymerase chain reaction. Results: DEX treatment preserved renal function and reduced tubular damage score of mice after cisplatin administration. Mice treated with DEX exhibited less apoptotic tubular cells in response to cisplatin insult, which was associated with decreased Bax and reduced activation of p53 and caspase-3. DEX suppressed the infiltration of macrophages and T cells into the kidneys following cisplatin treatment, which was involved in the inhibition of NF-κB activation and decreased expression of TNF-α, IL-1β, IL-6, and MCP-1. Furthermore, we showed that the renoprotective effect conferred by DEX may be related to α adrenoceptor-dependent pathway. Conclusion: We demonstrate that DEX protects the kidney against cisplatin-induced AKI by the regulation of apoptosis and inflammatory response. [ABSTRACT FROM AUTHOR]

Scanning superconducting quantum interference device (sSQUID) microscopy is currently one of the most effective methods for direct and sensitive magnetic flux imaging on the mesoscopic scale. A SQUID-on-chip (SOC) design allows integration of field coils for susceptometry in a gradiometer setup which is very desirable for measuring magnetic responses of quantum matter. However, the spatial resolution of such a design has largely been limited to micrometers due to the difficulty in approaching the sample. Here, we used electron beam lithography technology in the fabrication of the 3D nano-bridge-based SQUID devices to prepare pick-up coils with diameters down to 150 nm. Furthermore, we integrated the deep silicon etching process in order to minimize the distance between the pick-up coil and the wafer edge. Combined with a tuning-fork-based scanning head, the sharpness of the etched chip edge enables a precision of 5 nm in height control. By scanning measurements on niobium chessboard samples using these improved SQUID devices, we demonstrate sub-micron spatial resolutions in both magnetometry and susceptometry, significantly better than our previous generations of nano-SQUIDs. Such improvement in spatial resolution of SOC is a valuable progress for magnetic imaging of quantum materials and devices in various modes. [ABSTRACT FROM AUTHOR]

Flowers are the main sexual reproductive organs in plants. The shapes, colours and scents of corolla of plant flowers are involved in attracting insect pollinators and increasing reproductive success. The process of corolla senescence was investigated in Ipomoea purpurea (Convolvulaceae) in this study., In the research methods of plant anatomy, cytology, cell chemistry and molecular biology were used., The results showed that at the flowering stage cells already began to show distortion, chromatin condensation, mitochondrial membrane degradation and tonoplast dissolution and rupture. At this stage genomic DNA underwent massive but gradual random degradation. However, judging from the shape and structure, aging characteristics did not appear until the early flower senescence stage. The senescence process was slow, and it was completed at the late stage of flower senescence with a withering corolla., We may safely arrive at the conclusion that corolla senescence of I. purpurea was mediated by programmed cell death (PCD) that occurred at the flowering stage. The corolla senescence exhibited an obvious temporal rhythm, which demonstrated a high degree of coordination with pollination and fertilization. [ABSTRACT FROM AUTHOR]

Summary: China is a middle-risk country for hip fracture at present, which differs from previous data that it was low-risk. By 2050, the total number of hip fractures in people older than 65 years is predicted to be 1.3 million. Introduction: To assess hip fracture incidence in China and examine the heterogeneity of hip fracture in seven geographical regions of China. Methods: There were 238,230 hip fracture patients aged 65 years or older from 2013 to 2016 from a large national in-patients database (HQMS) involving 30.6 million hospitalizations. Taking into account the total national hospitalization rate per calendar year, we estimated the incidence of hip fracture per 100,000 residents older than 65 years in China overall and in seven geographical Chinese regions. Results: The proportion of men and women older than 65 years with hip fractures was 1.00:1.95. Between 2013 and 2016, the number of hip fractures per 100,000 people age 65+ was 278. China has vast territories; the number of hip fractures per 100,000 people over 65 years old was 202 in Northeast China and 374 in Northwest China. Northwest has higher altitude, lower population density, is less developed with lower urbanization than Northeast China which is low altitude, and highly urbanized. Conclusions: China should no longer be regarded as a low-risk country for hip fracture. By 2050, the total number of hip fractures in people older than 65 years in China is predicted to be 1.3 million. Higher altitude areas had higher hip fracture rates than lower altitude, higher urbanized areas. [ABSTRACT FROM AUTHOR]

We studied and improved the performance of a terahertz (THz) direct detector based on the superconducting NbN hot electron bolometer (HEB) integrated with microwave readout for imaging arrays and other applications. A 6 nm thick NbN microbridge at the feed point of a twin-slot antenna is embedded into a high-Q quarter-wavelength coplanar waveguide (CPW) resonator made from a 350 nm thick NbN film which is weakly coupled to a CPW feedline. THz direct detection was performed at a signal frequency of 0.66 THz at a bath temperature of 4.2 K. When operating at a low input microwave power level, the device acting as a microwave kinetic inductance detector with a kinetic inductance fraction of 0.45 changes the surface impedance of the resonator in response to incident THz radiation. The estimated optical noise equivalent power (NEP) is ∼0.23 pW · Hz−0.5 which shows about one order of magnitude improvement compared to that of the traditional voltage-biased NbN HEBs. The improved performance of the THz direct detectors with lower NEP and easy readout makes them promising in imaging with a large number of the array pixels. [ABSTRACT FROM AUTHOR]

Externally generated, axial magnetic fields used to confine high-current plasma beams in compact linear devices are usually 0.5 Tesla or less and can be insufficient to suppress plasma instabilities. Such an issue is addressed in this study by closely winding the current-carrying cable around a small chamber attached to the end of a linear device. The magnetic field generated inside the small chamber during the high-current pulse reached 0.8 Tesla at the peak current of 10.83 kA. Formation of a steady plasma beam through a mixture of argon, hydrogen and helium was photographed by a high-speed camera at the instant of the peak current. The beam width profile starts from over 24.8 mm at the upstream location and becomes thinner with distance down-stream. At the location of laser-interferometer measurement, at the right-most viewing window on the test chamber, the beam width was estimated as 7.4 mm and plasma density was evaluated to be 1.0 × 1022 m−3, an increase of two orders of magnitude compared to a previous study. A simple relationship was derived for the plasma density as a function of beam width. Based on examination of the metal target at the far end, the final beam width was estimated as 50 µm, with the plasma density evaluated to be 4.31 × 1022 m−3, with a calculated ion energy of 4.35 keV, consistent with x-ray spectrum measurements. [ABSTRACT FROM AUTHOR]

Dielectronic recombination (DR) rate coefficients for carbon-like 40Ca14+ forming nitrogen-like 40Ca13+ have been measured using the electron–ion merged-beam technique at the heavy-ion storage ring CSRm at the Institute of Modern Physics in Lanzhou, China. The measured DR rate coefficients in the energy range from 0 to 92 eV cover most of the DR resonances associated with 2s22p2 → 2s22p2 and 2s22p2 → 2s2p3 core transitions (ΔN = 0). Theoretical calculations of the DR cross sections were carried out by using two different state-of-the-art atomic theoretical techniques, multiconfiguration Breit–Pauli (MCBP) code AUTOSTRUCTURE and relativistic configuration interaction code FAC, to compare with the experimental rate coefficients. The theoretical calculations agree with the experimental results at collision energy higher than 10 eV. However, significant discrepancies of resonance energies and strengths can be found at collision energy below 8 eV. Temperature-dependent plasma recombination rate coefficients were derived from the measured DR rate coefficients in the energy range from 0.1 to 1000 eV and compared with the recommended atomic data from the literature. The theoretical data of Gu et al. and Zatsarinny et al. are 30% lower than the experimental results at the temperatures of photoionized plasmas, but have a very good agreement at the temperatures of collisionally ionized plasmas. Other previously published theoretical data of Jacobs et al. and Mazzotta et al. by using Burgess formula and LS-coupling calculations significantly underestimate the plasma rate coefficients in the low temperature range. The present results comprise a set of benchmark data suitable for astrophysical modeling. [ABSTRACT FROM AUTHOR]

The billets of M3 high speed steel (HSS) with or without niobium addition were prepared via spray forming and forging, and the corresponding microstructures, properties were characterized and analysed. Finer and uniformly-distributed grains without macrosegregation appear in the as-deposited high speed steel that are different to the as-cast high speed steel, and the primary austenite grain size can be decreased with 2% niobium addition. Niobium appears in primary MC-type carbides to form Nb6C5 in MN2 high speed steel, whereas it contributes less to the creation of eutectic M6C-type carbides. With same treatments to forged MN2 high speed steel and M3 high speed steel, it is found that the peak hardness of these two steels are almost the same, but the temper-softening resistance of the former is better. With higher high-temperature hardness of the forged MN2 high speed steel, its temper softening above 600 °C tends to slow down, which is related to the precipitation of the secondary carbides after tempering. A satisfactory solid solubility of Vanadium and Molybdenum can be obtained by Nb substitution, precipitation strengthening induced by larger numbers of nano-scaled MC and M2C secondary carbides accounts for the primary role of determining higher hardness of MN2 high speed steel. The results of the wear tests show that the abrasive and adhesive wear resistance of MN2 high speed steel can be improved by the grain refinement, existence of harder niobium-containing MC carbides, as well as solute strengthening by more solute atoms. The oxidational wear behavior of MN2 high speed steel can be markedly influenced by the presence of the high hardness and stabilization of primary niobium-containing MC-type carbides embedded in the matrix tested at 500 °C or increased loads. The primary MC carbides with much finer sizes and uniform distribution induced by the combined effects of niobium addition and atomization/deposition would be greatly responsible for the good friction performance of the forged MN2 high speed steel. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency and quality of the laser cladding process, a TiBCN coating was successfully fabricated on a 7075 aluminium alloy substrate successfully based on the statistical analysis and optimization of process parameters. The effect of laser power, scanning speed and powder feed rate on the TiBCN coating geometry characteristics were investigated. Response surface methodology (RSM) was used to develop mathematical models. The analysis of variance (ANOVA) method was employed to find relationships between process parameters and output responses. The results indicate that the model can be used to illustrate the relationship between the geometrical characteristics of the coating and the laser cladding processing parameters. The predicted results, obtained using the optimized parameters from the models, are consistent with the experimental results. Based on the results of the optimization experiment, the optimum parameters were the following: laser power of 1200 W, scanning speed of 3 mm/s and a powder feed rate of 200 mg/s. [ABSTRACT FROM AUTHOR]

We locked a 1064 nm continuous wave (CW) laser to a Yb:fiber optical frequency comb stabilized to an ultrastable 972 nm CW laser with the feed-forward method. Consequently, the stability and coherent properties of the ultrastable laser are precisely transferred to the 1064 nm CW laser through the frequency comb's connection. The relative linewidth of the frequency-stabilized 1064 nm CW laser is narrowed to 1.14 mHz, and the stability reaches 1.5 × 10−17/s at the optical wavelength of 1064 nm. The phase noise characterization in the 1 mHz–10 MHz range is presented to indicate that feed-forward locking a CW laser to an ultrastable comb will offer a potential technique for many important applications, such as optical frequency synthesis and gravitational wave detection. [ABSTRACT FROM AUTHOR]

Abstract: In order to study the molecular mechanism involved in meat quality differences especially tenderness variance caused by castration in Qinchuan cattle males, this study investigated the gene expression profile of Longissimus thoracis (LT) muscle and screened differentially expressed genes in LT muscle from both intact male and castrated male Qinchuan cattle at 36months of age utilising Bovine Genome Array. Significance Analysis of Microarrays (SAM) was used to identify the differentially expressed genes, Go (Gene Ontology) and pathway analyses were conducted on which by a free Web-based Molecular Annotation System 2.0 (MAS 2.0). Approximately 11,000 probe sets representing 10,000 genes were detected in LT muscle of 36-month-old Qinchuan cattle. After SAM analysis of the microarray data, 142 genes were shown to be differentially expressed. These genes were predominantly involved in collagen fibril organization and synthesis, regulation of cell growth and development and striated muscle contraction. The significant pathways involved mainly included ECM–receptor (extracellular matrix-receptor) interaction, cell communication and focal adhesion. Quantitative real-time PCR (qRT-PCR) was performed to validate some differentially expressed genes identified by microarray. These patterns of gene expression may contribute to understanding the molecular mechanism of better meat quality of beef derived from castrates than from intact males. [Copyright &y& Elsevier]

This study investigated the effects of a combination of tiletamine-zolazepam and xylazine plus tramadol (TZXT) and compared the efficacy of this combination with that of tiletaminezolazepam and xylazine (TZX) for providing anaesthesia in Chinese experimental miniature pigs. Fourteen healthy, eight-month-old miniature pigs of both sexes were immobilised with TZXT or TZX on two different occasions. The pigs' immobilisation and analgesia scores and baseline physiological parameters (heart rate, respiratory rate, non-invasive systolic, diastolic and mean arterial blood pressures, arterial haemoglobin oxygen saturation and rectal temperature) were determined before and five, 10, 30, 45, 60, 80 and 100 minutes after the administration of TZXT or TZX. Pigs in both groups became laterally recumbent within three minutes. Some physiological parameters were changed after administration of the drug combinations, but they remained within biologically acceptable limits and were not significantly different between the two treatments. The use of TZXT resulted in better induction time and quality of recovery compared with TZX, with higher scores for sedation, analgesia, muscle relaxation, posture and auditory response. The animals were much calmer during recovery after TZXT immobilisation. [ABSTRACT FROM PUBLISHER]

The bottom up multiscale finite element modelling that is based on the sequential consideration of the fibre/interface/matrix scale and the tow/matrix/coat scale is employed to predict the effective elastic modulus of the plain wave multiphase and multilayer silicon carbide ceramic matrix composite. Instead of using the homogenisation method, the strain energy based method that is advantageous in computing efficiency and numerical implementation is adopted for the multiscale analysis and evaluation of effective properties. First, the effective properties of tows are computed on the fibre/interface/matrix scale. They are then incorporated into the tow/matrix/coat scale to evaluate the effective properties of the composite. Numerical results obtained by the proposed method and model show a good agreement with the results measured experimentally. [ABSTRACT FROM AUTHOR]

This paper reviews recently published literature, most of which was published in Chinese, and searches for regional patterns of Holocene changes useful in depicting global patterns. The Holocene in the Xinjiang region can be divided into three stages: a warming and dry early stage (from 11 ∼ 10 to 8 ∼ 7 ka BP), a warm and wet middle stage (from 8 ∼ 7 to 4.5 ∼ 3 ka BP) and a fluctuating cool and dry late stage (since 4.5 ∼ 3 ka BP). The Holocene in the northern Tibetan Plateau can also be divided into three stages: a warming and wet stage (from 10.5 ∼ 10 to 5 ∼ 4 ka BP), followed by a variable drying and probably warm stage (5 ∼ 4 to 3 ka BP) and ending with a cool and dry stage (since 3 ka BP). In the Inner Mongolian Plateau, the early Holocene (from 10.5 ∼ 9.5 to 8 ∼ 7.5 ka BP) was warming and dry, and a warm and wet climate occurred from 7.5 to 3.5, during which the best time was 6.3–3.8 ka BP; the climate has been variably drying and probably cooling since 3.5 ka BP. In the northwestern part of the Loess Plateau, several Holocene palaeosols have been identified (10–9, 7.5–5, 4–3 and 2.7–2 ka BP) with the 7.5–5 ka BP palaeosol being most strongly expressed. The best-developed palaeosol-equivalent in major valleys is a swamp-wetland facies deposited between 8885 and 3805 14C yr BP under an extremely wet regime. The climate has fluctuated significantly at least three times around a dry and probably cool regime after the swamp-wetland facies-depositional period. Our summary shows that the Holocene Climatic Optimum occurred nearly contemporaneously (8–5 ka BP) at all sites in the Xinjiang region, in the Inner Mongolian Plateau and in the northwestern part of the Loess Plateau. A warming and wet early Holocene (10–8 ka BP) in the northern Tibetan Plateau is most likely related to high effective soil moisture resulting from snow and ice melting. We propose here that the middle Holocene Climatic Optimum (8–5 ka BP) in arid to semi-arid China was primarily a delayed response of the low latitude oceans to high latitude peak insolation (9–8 ka BP). [ABSTRACT FROM AUTHOR]

The article reports on a research based on the Robust Fault Detection (RFD) problem with the support of optimization techniques and the LMI approach. First, a necessary and sufficient condition and then a RFD problem for systems with structured uncertainties in the system matrices are planned to design RFD observers. The approaches tend to design robust fault detection observers to increase the fault detection and to attenuate the effects resulting to unknown inputs and uncertainties.

Abstract: Phlebotomine sandflies (Diptera: Phlebotomidae) are vectors of the zoonotic disease leishmaniasis. To better understand the distribution of phlebotomine sandflies in order to facilitate control of leishmaniasis transmission, the present study explored the impacts of climate and landscape on local abundances of Phlebotomus chinensis in northwestern mainland China. Identification records were used to create a geodatabase for the locations at which P. chinensis had been collected in the region, and a regional‐scale map was developed to show the distribution of P. chinensis. Location data and data on environmental factors during the years in which the samples were collected were incorporated, and a presence‐only modelling method was used to evaluate the species' habitat preferences and to predict its potential distribution in northwestern mainland China. Jackknife analysis revealed that several meteorological variables, including maximum temperature in the warmest quarter, precipitation in the driest month, daily average temperature and daily precipitation, significantly affected the presence of this species. Moreover, the presence of P. chinensis was significantly associated with grassland and shrubland. Probability distributions using maximum entropy were used to map the distribution ranges of P. chinensis based on suitable habitats in northwestern mainland China. The models generated can be used to develop detailed strategies for the prevention and control of leishmaniasis. [ABSTRACT FROM AUTHOR]

With a thin gold layer, we fabricated mesa-like shunted intrinsic Josephson junction stacks on Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub 8+x] single crystals. Instead of the multibranch structure and large voltage jumps often observed in conventional intrinsic junctions, current-voltage characteristics typical of resistively shunted junctions were obtained. Individual Shapiro steps were clearly visible with irradiation at frequencies from a few to 20 GHz. The experiments demonstrated not only the ac Josephson effects directly but also the possibility of employing intrinsic Josephson junctions in high-frequency applications. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This paper investigates total ionization dose (TID) effects on the electrical characteristics of Al2O3-/HfO2-/Al2O3-based charge trapping memory (CTM) devices by 10-keV X-ray. The Al2O3 layers serve as tunnel and blocking oxides, respectively, while HfO2 layer acts as charge-trapping layer. The C–V curves in pristine state shifted toward negative direction, but dc memory window almost kept the same after irradiation. Storage electrons decreased significantly with accumulated dose and reached approximately the same final value regardless of initial values. The impact of TID irradiation on program and erase conditions is also investigated. The program ability still worked well, but the erase ability disappeared gradually after irradiation. The physical mechanisms triggered by TID irradiation on Al2O3-/HfO2-/Al2O3-based CTM structure are discussed in detail with energy band diagrams. [ABSTRACT FROM PUBLISHER]

The donor/acceptor interface in a standard CuPc/C60 organic solar cell was modified by insertion of a thin layer of molybdenum trioxide (MoO3). An ultrathin layer of MoO3 between the donor and acceptor increased the open-circuit voltage (VOC) from 0.45 to 0.85 V. The enhancement in VOC is explained by the increase in the energy level offset between the lowest unoccupied molecular orbital of the acceptor and the highest occupied molecular orbital of the donor (EDHOMO-EALUMO). The explanation is supported by the energy level analysis of the donor/acceptor interface by ultraviolet photoemission spectroscopy and x-ray photoemission spectroscopy. [ABSTRACT FROM AUTHOR]

Ni-doped ZnO nanocrystals have been synthesized by a wet chemical reaction. The nanocrystals have been investigated carefully by high resolution transmission electron microscopy and all the particles are found to be the known wurtzite ZnO. X-ray photoelectron spectroscopy and Raman spectra results provide the evidence that Ni2+ is incorporated into the ZnO lattice at Zn2+ site. Magnetic property measurements reveal that the as-grown Zn1-xNixO nanocrystals exhibit room temperature ferromagnetic behaviors with saturation magnetization of 0.01 emu/g and Curie temperature above 340 K for Ni concentration of ∼1% in atomic ratio. [ABSTRACT FROM AUTHOR]

Single-crystal whiskers of Y1Ba2Cu3Ox with a length of about 4 mm were grown from an Sb-doped pre- cursor. The optimum nominal composition of precursors in this Sb-doping method is Y2Ba2.75Cu3Sb0.5Ox. Sb is not detected in the whiskers by energy-dispersive x-ray spectroscopy (EDS). The standard 4-probe transport measurements for the as-grown whiskers show a critical temperature Tc of about 90 K and a c-axis critical current density Jc of 9.51 × 104 A/cm² at 89 K. [ABSTRACT FROM AUTHOR]

We report a practical superconducting terahertz (THz) source, comprising a stack of Bi2Sr2CaCu2O8 intrinsic Josephson junctions (IJJs) and a vanadium dioxide (VO2) tunable attenuator with coplanar interdigital contacts. The electrical triggering phase transitions are observed not only at room temperature, but also at low temperatures, which provides a proof of the electrical triggering. Applying this, the VO2 attenuator is implemented for the independent regulations on the emission powers from the IJJ THz emitter, remaining frequencies and temperatures unchanged. The attenuation can be tuned smoothly and continuously within a couple of volts among which the maximum is, respectively, -5.6 dB at 20K or -4.3 dB at 25K. Such a power-adjustable radiation source, including the VO2 attenuator, can further expand its practicability in cryogenic THz systems, like superconducting THz spectrometers. [ABSTRACT FROM AUTHOR]

Background: Extra-nodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue originating in the liver is less common. Case presentation: We described the clinical presentation, immunohistochemistry, and immunophenotypes of this lymphoma, which was misdiagnosed with tiny hepatic carcinoma in a 44-year-old woman with hepatitis C; the patient underwent left lateral sectionectomy. The immunophenotype identified the most of the lymphoid cells as positive CD20, CD34, Ki67, CD3, CD4, CD79a, CD45RO, MUM-1, and CD5 and negative CD10, CD15, CD30, ACT, CK, CRO, DES, and HMB45. The diagnosis of primary hepatic mucosa-associated lymphoid tissue (MALT) was made by histology after surgery; the patient went through the excellent recovery with no chemotherapy and is disease free for 27 months. Conclusions: Primary hepatic MALT is less common with incidental finding; local resection is beneficial due to its oncological indolence. [ABSTRACT FROM AUTHOR]

To selectively reduce the yield of hydrogen cyanide in cigarette smoke, porous carboxymethylcellulose microspheres were prepared through the sol-gel method. Cupric ions, the functional groups that have high complexing ability to hydrogen cyanide, were introduced to the carboxymethylcellulose microspheres during the sol-gel process. The microspheres were characterised using nitrogen adsorption and scanning electron microscopy. The microspheres have a predominantly macroporous structure indicating weak physisorption properties, but sufficient functional cupric ions groups to selectively adsorb hydrogen cyanide. With these carboxymethylcellulose microspheres as filter additives, the smoke yield of hydrogen cyanide could be reduced by up to 42%, indicating great potential of these microspheres as absorbents for removing hydrogen cyanide from cigarette smoke. [ABSTRACT FROM AUTHOR]

To selectively reduce the yield of hydrogen cyanide in cigarette smoke, porous carboxymethylcellulose microspheres were prepared through the sol-gel method. Cupric ions, the functional groups that have high complexing ability to hydrogen cyanide, were introduced to the carboxymethylcellulose microspheres during the sol-gel process. The microspheres were characterised using nitrogen adsorption and scanning electron microscopy. The microspheres have a predominantly macroporous structure indicating weak physisorption properties, but sufficient functional cupric ions groups to selectively adsorb hydrogen cyanide. With these carboxymethylcellulose microspheres as filter additives, the smoke yield of hydrogen cyanide could be reduced by up to 42%, indicating great potential of these microspheres as absorbents for removing hydrogen cyanide from cigarette smoke. [ABSTRACT FROM AUTHOR]

Abomasal cannulation, an important research tool in experimental procedures, provides a method for the placement of an abomasal cannula in sheep. he aim of this study was to describe a technique for laparoscopic abomasal cannulation in sheep. It was performed in six anaesthetised sheep positioned in dorsal recumbency using three portals in the abdomen. he irst absorbable traction suture was placed 1 cm cranial to the determined abomasal cannula site. A stab incision was made with a laparoscopic monopolar hook electrode in the middle of a purse-string suture placed around the abomasal cannula site. he T-shaped cannula was inserted into the abomasum lumen through the stab incision, and the second traction suture was then placed 1 cm caudal to the abomasal cannula site. he T-shaped abomasal cannula was pulled out of the abdominal cavity through the exit wound located 3-5 cm lateral and 10-12 cm cranial to the right side of the umbilicus. he two traction sutures were tied. he T-shaped cannula was secured to the skin with a inger-trap suture. Repeat laparoscopy was performed 1 month later. Firm adhesion between the abomasum and abdominal wall was observed in all sheep, with no evidence of leakage or peritonitis. No major intraoperative or postoperative complications were encountered. he median surgical time was 49 min, with a range from 42 to 58 min. he abomasal contents were collected easily. In conclusion, laparoscopic abomasal cannulation is safe and easy to perform. Its low complication rates and the "ideal" placement of the tube into the abomasum make it an especially attractive alternative to traditional surgical abomasal cannulation in veterinary practice. [ABSTRACT FROM AUTHOR]

Compared with conventional DGA (dissolved gas analysis) method for on-line monitoring of power transformers, FBG (fiber Bragg grating) hydrogen sensor represents marked advantages over immunity to electromagnetic field, time-saving, and convenience to defect location. Thus, a novel FBG hydrogen sensor based on Pd/Ag (Palladium/Silver) along with polyimide composite film to measure dissolved hydrogen concentration in large power transformers is proposed in this article. With the help of Pd/Ag composite coating, the enhanced performance on mechanical strength and sensitivity is demonstrated, moreover, the response time and sensitivity influenced by oil temperature are solved by correction lines. Sensitivity measurement and temperature calibration of the specific hydrogen sensor have been done respectively in the lab. And experiment results show a high sensitivity of 0.055 pm/(µl/l) with instant response time about 0.4 h under the typical operating temperature of power transformers, which proves a potential utilization inside power transformers to monitor the health status by detecting the dissolved hydrogen concentration. [ABSTRACT FROM AUTHOR]

We used one-dimensional coupled sine-Gordon equations combined with heat diffusion equations to numerically investigate the thermal and electromagnetic properties of a 300 pm long intrinsic Josephson junction stack consisting of N = 700 junctions. The junctions in the stack are combined with M segments where we assume that inside a segment all junctions behave identically. Most simulations are for M = 20. For not too high bath temperatures there is the appearance of a hot spot at high-bias currents. In terms of electromagnetic properties, robust standing-wave patterns appear in the current density and electric field distributions. These patterns come together with vortex/antivortex lines across the stack that correspond to jr-kink states, discussed before in the literature for a homogeneous temperature distribution in the stack. We also discuss scaling of the thermal and electromagnetic properties with M, on the basis of simulations with M between 10 and 350. [ABSTRACT FROM AUTHOR]

The efficiency droop of InGaN/GaN(InGaN) multiple quantum well (MQW) light emitting diodes (LEDs) with thin quantum barriers (QB) is studied. With thin GaN QB (3 nm-6 nm thickness), the efficiency droop is not improved, which indicates that hole transport cannot be significantly enhanced by the thin GaN QBs. On the contrary, the efficiency droop was remarkably reduced by using a InGaN staircase QB (InGaN SC-QB) MQWs structure where InGaN SC-QBs lower the transport energy barrier of holes. The efficiency droop ratio was as low as 3.3% up to 200 A/cm² for the InGaN SC-QB LED. By using monitoring QW with longer wavelength we observe a much uniform carrier distribution in the InGaN SC-QB LEDs, which reveals the mechanism of improvement in the efficiency droop. [ABSTRACT FROM AUTHOR]

We report on Bi2Sr2CaCu2O8 (BSCCO) intrinsic Josephson junction stacks with improved cooling, allowing for a remarkable increase in emission frequency compared to the previous designs. We started with a BSCCO stack embedded between two gold layers. When mounted in the standard way to a single substrate, the stack emits in the range of 0.43-0.82 THz. We then glued a second, thermally anchored substrate onto the sample surface. The maximum voltage of this better cooled and dimension-unchanged sample was increased and, accordingly, both the emission frequencies and the tunable frequency range were significantly increased up to 1.05 THz and to 0.71 THz, respectively. This double sided cooling may also be useful for other "hot" devices, e.g., quantum cascade lasers. [ABSTRACT FROM AUTHOR]

Cardiorespiratory effects were assessed during ketamine/xylazine premedication followed by emulsified isoflurane anaesthesia in swine undergoing experimental embryo transplantation. Ketamine (10 mg/kg) and xylazine (3.5 mg/kg) were premedicated intravenously, followed by continuous administration of intravenous emulsified isoflurane (2.8 ml/kg/h). Cardiorespiratory parameters, including heart rate, respiratory rate, mean arterial blood pressure, arterial oxygen saturation, and rectal temperature, were recorded in sows undergoing surgical embryo transplantation. Ketamine/xylazine premedication resulted in anaesthetic induction and lateral recumbency within 1 minute without any adverse effects. The physiological changes observed after drug administration remained within biologically acceptable limits. In conclusion, the combination of ketamine/xylazine provided anaesthetic induction, muscle relaxation, and analgesia sufficient for emulsified isoflurane intravenous anaesthesia. There were no adverse events in the experimental animals. This finding supports the use of emulsified isoflurane following ketamine/xylazine premedication in pigs. [ABSTRACT FROM AUTHOR]

We have performed detailed ac susceptibility measurements to investigate the vortex dynamics in a Ca10(Pt3As8)[(Fe1-xPtx)2As2]5 single crystal as a function of temperature, frequency, ac amplitude, and dc field. The field dependence of the activation energy U is derived in the framework of thermally activated flux creep theory, yielding a power law dependence of U ~ Hɑ with ɑ ≈ -1.0 for H above 0.30 T, while below 0.3 T U is independent of the field. The activation energy reaches 104K at low fields, suggesting strong pinning in the material. The nonlinear function of the activation energy vs. the current density is determined, which shows logarithmic dependence U(J) ∞ lnJ. [ABSTRACT FROM AUTHOR]

The domestic yak ( Bos grunniens) is an iconic symbol of animal husbandry at high altitudes. Yaks exhibit unique external characteristics including long hair and large horns. However, hornless yaks can be found in different breeds and different populations. The hornless trait is also known as polled, and the POLL locus has been fine-mapped to chromosome 1 in cattle ( Bos taurus), although the underlying genetic basis of the polled trait is still unclear in the yak. Thus, we performed an association study to identify the genetic polymorphisms responsible for the polled trait in the yak. Fifty polled Datong domestic yaks and 51 horned individuals were selected randomly from a huge herd and were used as the case and control groups respectively for the association analysis. Twelve genes located in the candidate region of the POLL locus in cattle were used as references to detect DNA polymorphisms related to yak polledness, which were analyzed by sequencing and a high-resolution melting test. We applied Fisher's exact test and haplotype analysis to show that a 147-kb segment that included three protein-coding genes C1H21orf62, GCFC1 and SYNJ1 was the most likely location of the POLL mutation in domestic yaks. [ABSTRACT FROM AUTHOR]

We have used the ac magnetic susceptibility to investigate the vortex state in an optimally doped p-type Ba0.5K0.5Fe2As2 single crystal under various ac and dc fields. A peak effect is observed in the temperature dependence of the in-phase ac susceptibility, indicating an order-disorder transition on the vortex phase diagram. The peak effect displays an anomalous history effect compared with other type-II superconductors, which we ascribe to the strong pinning existing in the material. We observe the development of a small dissipation peak at the temperature Tp2 slightly below the peak effect region. Similar to the peak effect boundary, Tp2 delimits a region in the H-T phase diagram which is independent on the ac field amplitude. We argue that this small peak may arise from the softening of the vortex lattice, leading to a collective pinning of the whole vortex lattice. This effect assists and further enhances the peak effect occurring in the Ba0.5K0.5Fe2As2 superconductor. [ABSTRACT FROM AUTHOR]

Background:Our previous study revealed that proline-rich tyrosine kinase 2 (Pyk2) is implicated in both anchorage-independent growth and anoikis resistance in lung cancer cells. This study aims to explore the expression and clinical significance of Pyk2 and its phosphorylated forms in non-small-cell lung cancer (NSCLC).Methods:The mRNA and protein levels of Pyk2 or cancer stem cell markers (ALDH1a1, ABCG2 and Bmi-1) were either examined by reverse transcription-PCR or western blotting. An immunohistochemistry (IHC) assay was conducted to analyse the expression of Pyk2 and its phosphorylated forms in 128 NSCLC cases.Results:The levels of Pyk2 mRNA, total protein, and its phosphorylated form pY881 were higher in lung cancer lesions than in the paired noncancerous tissues. The IHC analysis showed the levels of the Pyk2 and Pyk2[pY881] proteins were highly expressed in 70 (54.7%) and 77 (60.2%) cases, respectively. Both Pyk2 and Pyk2[pY881] were independent prognostic factors for NSCLC patients. The gain and loss study of Pyk2 function revealed that Pyk2 could upregulate the expression of ALDH1a1, ABCG2 and Bmi-1 and enhance the ability of colony formation in soft agar assay in A549 and H460 cells.Conclusion:Both Pyk2 and phosphorylated Pyk2[pY881] are potential prognostic factors and therapeutic targets for NSCLC. [ABSTRACT FROM AUTHOR]

We report a Mn substitution strategy to tailor the morphology, size, surface of LiCo1-xMnxPO4 (x = 0·2, 0·5 and 0·8) materials using a facile organic acid mediated hydrothermal approach. The results show that the Mn substitution plays a profound role in reducing the particle size, stabilising the surface, and improving the diffusivity of LiCo1-xMnxPO4 materials, thus leading to much enhanced electrochemical performance compared with LiCoPO4. However, when excessive Mn (e.g. x = 0·8) is present in the olivine crystal, the performance of LiCo1-xMnxPO4 degrades, possibly due to Jahn-Teller lattice distortion. As a result, the LiCo0·5Mn0·5PO4 displays the best electrochemical performance in terms of capacity delivery, cyclability and rate capability. Therefore, the Mn substitution in LiCoPO4 could be an efficient way to achieve high energy density and long cycle life for high voltage materials. [ABSTRACT FROM AUTHOR]

Pulsed laser and heavy-ion experiments were carried out on a commercial-off-the-shelf DC/DC pulse width modulation controller to study the equivalent laser Linear Energy Transfer (LET) at wavelengths of 750 nm, 800 nm, 850 nm and 920 nm. The laser experiments showed that the shorter wavelength laser has smaller threshold energy to generate single-event transient pulses. The cross-sections versus heavy-ion LET and laser energy per pulse were obtained and correlated. The heavy-ion and laser cross-sections fit well considering the effects of metal layers on the chip. The results of this research facilitate the future pulsed laser testing by providing explicit coefficients to evaluate the equivalent laser LET, which can be used to replace costly heavy-ion testing. [ABSTRACT FROM AUTHOR]

We have combined a stand-alone Bi2Sr2CaCu2O8 intrinsic Josephson junction stack, emitting terahertz radiation, with a YBa2Cu3O7 grain boundary Josephson junction acting as detector. The detector is mounted on a lens, positioned 1.2 cm away from the emitter on a similar lens. With the emitter radiating at 0.5 THz, we observed up to 7 Shapiro steps on the current-voltage characteristic of the detector. The ac current induced in this junction was 0.9 mA, and the dissipated power was 1.8 μW. The setup, although far from being optimized, may be considered as a first step towards an integrated high-Tc receiver. [ABSTRACT FROM AUTHOR]

Small populations may suffer more severe pollen limitation and result in Allee effects. Sex ratio may also affect pollination and reproduction success in dioecious species, which is always overlooked when performing conservation and reintroduction tasks. In this study, we investigated whether and how population size and sex ratio affected pollen limitation and reproduction in the endangered Ottelia acuminata, a dioecious submerged species. We established experimental plots with increasing population size and male sex ratio. We observed insect visitation, estimated pollen limitation by hand-pollinations and counted fruit set and seed production per fruit. Fruit set and seed production decreased significantly in small populations due to pollinator scarcity and thus suffered more severe pollen limitation. Although frequently visited, female-biased larger populations also suffered severe pollen limitation due to few effective visits and insufficient pollen availability. Rising male ratio enhanced pollination service and hence reproduction. Unexpectedly, pollinator preferences did not cause reduced reproduction in male-biased populations because of high pollen availability. However, reproductive outputs showed more variability in severe male-biased populations. Our results revealed two component Allee effects in fruit set and seed production, mediated by pollen limitation in O. acuminata. Moreover, reproduction decreased significantly in larger female-biased populations, increasing the risk of an Allee effect. [ABSTRACT FROM AUTHOR]

Highly ordered Fe-Pt nanowire arrays were fabricated using anodic aluminum oxide templates by pulse DC electrodeposition. The influences of pulse ratio and frequency on the microstructural and magnetical properties of Fe-Pt nanowire arrays have been studied. The composition of Fe-Pt nanowires can be adjusted by pulse ratio and the crystallization of wires can be modified by pulse frequency. By choosing an optimal pulse ratio and pulse frequency, the Fe-Pt nanowire arrays with out-of plane coercivity up to 1620 Oe can be achieved. Annealing of Fe-Pt nanowire arrays could improve the crystallinity of wires and accordingly enhance the coercivity. [ABSTRACT FROM AUTHOR]

Within the time-dependent Ginzburg-Landau theory we study the dynamic properties of current-carrying superconducting strips in the presence of a perpendicular magnetic field. We found pronounced voltage peaks as a function of the magnetic field, the amplitude of which depends both on sample dimensions and external parameters. These voltage oscillations are a consequence of moving vortices, which undergo alternating static and dynamic phases. At higher fields or for high currents, the continuous motion of vortices is responsible for the mono-tonic background on which the resistance oscillations due to the entry of additional vortices are superimposed. Mechanisms for such vortex-assisted resistance oscillations are discussed. Qualitative changes in die magnetoresistance curves are observed in the presence of random defects, which affect the dynamics of vortices in the system. [ABSTRACT FROM AUTHOR]