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Semen is a measure of the reproductive efficiency of roosters, which affects the economic benefits of white‐feathered broilers. Over the years, research in this field has mainly focused on hens, while there have been fewer studies on the reproductive traits of roosters. To identify the genes related to the semen traits of roosters, we used a chicken 55 K SNP chip to genetically type the white‐feathered population (220) and performed imputation with resequencing data from 97 roosters. In total, 1 048 576 SNPs were obtained and used for genome‐wide association analysis of semen volume, from which 197 genome‐wide significant markers were identified, all within the interval of 13.82–16.12 Mb on chromosome 7. By combining our results with the biological functions of genes in the interval, four candidate genes were identified that potentially relate to semen volume: FAPP1, OSBPL6, SESTD1 and SSFA2. Our findings may provide a basis for further research on the genetic mechanism and marker‐assisted selection of semen volume in white‐feathered broilers. [ABSTRACT FROM AUTHOR]

Plasma synthesis of ammonia is a potential and sustainable way of nitrogen fixation. In this work, a series of M/Al2O3 (M =Co, Ni, Co–Ni) catalysts have been investigated to enhance the synthesis of NH3 from N2 and H2 in a dielectric barrier discharge (DBD) plasma reactor. Under the conditions of a volume ratio of N2:H2 of 1:1, a total gas flow rate of 200 mL min−1, and a discharge temperature of 200 °C, the order of the ammonia synthesis rate filled with different catalysts was Co–Ni/Al2O3 > Co/Al2O3 > Ni/Al2O3 > Al2O3 > only plasma. And the highest ammonia synthesis rate could be obtained was 1500 μmol g−1 h−1 by using Co–Ni/Al2O3 as the catalyst. Further research found that compared with single metal catalysis, on the one hand, the presence of Co–Ni bimetal reduced the total amount and strength of acidic sites on the catalyst surface, which is beneficial for the desorption of synthesized ammonia gas. On the other hand, the presence of Co–Ni bimetal enhanced the plasma discharge observed by the ICCD camera. At the same time, the electrical characterization was found changed with different catalysts added in the plasma synthesis process. Adding a Co–Ni bimetal loaded catalyst in the reaction system increased the average electric field (E) and improved the power efficiency. [ABSTRACT FROM AUTHOR]

Here, we report the successful synthesis of a spin- and charge-decoupled diluted magnetic semiconductor (DMS) (Ca,Na)(Zn,Mn)2As2, crystallizing into the hexagonal CaAl2Si2 structure. The compound shows a ferromagnetic transition with a Curie temperature up to 33K with 10% Na doping, which gives rise to carrier density of np∼1020cm-3. The new DMS is a soft magnetic material with HC<400 Oe. The anomalous Hall effect is observed below the ferromagnetic ordering temperature. With increasing Mn doping, ferromagnetic order is accompanied by an interaction between the local spin and mobile charge, giving rise to a minimum in resistivity at low temperatures and localizing the conduction electrons. The system provides an ideal platform for studying the interaction of the local spins and conduction electrons. [ABSTRACT FROM AUTHOR]

Stress induced by electrical current testing indeed has caused the formation of many whiskers growth in soldering applications. The aim of this investigation is to investigate the electrical current testing to the formation of whiskers. Also the mitigation could be achieved with the additional element of Nickel-Bismuth (Ni-Bi). Characterization of whisker growths are evaluated using the Scanning Electron Microscopy (SEM) on the deposits near anode and cathode areas. Synchrotron micro-XRF were performed on Sn0:7Cu0:05Ni1:5Bi at anode and cathode to accurately observe the distributions of elements in the sample. The obtained results demonstrate that the whisker growths with the effect of current stressing is associated with the intermetallic compound (IMCs) thickness on the anode and cathode areas. Finding shows that by addition of Ni-Bi elements can help to reduce the amount of whiskers form by refining the IMCs formation. [ABSTRACT FROM AUTHOR]

With the increasing of wind energy, it is necessary to develop an energy storage system to level the wave of wind power, and to develop a fault current limiter for improvement of the LVRT capability of the wind farm. An innovative idea to deal with the above problem is to develop a superconducting fault current limiter-magnetic energy storage system (SFCL-MES). In this paper, we report the progress of the superconducting coil for a 1-MJ/0.5-MVA FCL-SMES system. The coil consisted of 46 double pancakes, in which 8 pancakes were made of YBCO tapes and the others were made of Bi2223 tapes; the inductance of the coil was 13.3 H, and its rated current was 388 A while the maximum magnetic field was 3.5 T. This coil had been used for a FCL-SMES system, which was installed and tested at a wind farm connected to the live power grid. [ABSTRACT FROM AUTHOR]

In order to elucidate pressure-induced second superconducting phase (SC-II) in AxFe2−ySe2 (A = K, Rb, Cs, and Tl) having an intrinsic phase separation, we perform a detailed highpressure magnetotransport study on the isoelectronic, phase-pure (Li1−xFex)OHFe1−ySe single crystals. Here we show that its ambient-pressure superconducting phase (SC-I) with a critical temperature Tc ≈ 40 K is suppressed gradually to below 2 K and an SC-II phase emerges above Pc ≈ 5 GPa with Tc increasing progressively to above 50 K up to 12.5 GPa. Our high-precision resistivity data uncover a sharp transition of the normal state from Fermi liquid for SC-I to non-Fermi liquid for SC-II phase. In addition, the reemergence of high-Tc SC-II is found to accompany with a concurrent enhancement of electron carrier density. Without structural transition below 10 GPa, the observed SC-II with enhanced carrier density should be ascribed to an electronic origin presumably associated with pressure-induced Fermi surface reconstruction. [ABSTRACT FROM AUTHOR]

We describe the epidemiology of hepatitis B virus ( HBV) infection among women of reproductive age residing in areas of China that are highly endemic for chronic HBV, and provide evidence useful for decision-makers to guide strategies for preventing mother-to-child transmission of HBV, and assess the impact of perinatal transmission PMTCT by projecting HBsAg prevalence trends without interventions. We conducted a cross-sectional HBV serological survey of women, 15-49 years of age, residing in Fujian, Guangdong, Guangxi and Hainan provinces. Demographic and other subject-level data were collected in face-to-face interviews, after which we obtain blood specimens. Specimens were tested for HBV sero-markers by ELISA (Beijing Wantai Biological Pharmacy), and HBV DNA was tested with PCR (Hunan Sansure Biotech). Weighted HBsAg and HBV (either HBsAg+ or anti- HBc+ indicating either present or past infection) prevalences were 11.82% and 57.16%, respectively. Among the HBsAg-positive women, 27% were also HBeAg positive. The proportion of individuals with HBV DNA loads >105IU/mL declined with increasing age. Among HBsAg-negative women, 0.9% had occult HBV infection. The prevalence of chronic HBV infection among reproductive women in these highly endemic provinces is high, posing a threat to maternal health and risk of mother-to-child transmission. Prevention of mother-to-child transmission remains critically important. [ABSTRACT FROM AUTHOR]

This study aimed to determine if short-term nutrient alteration affects (1) ovarian morphology, (2) plasma and ovarian antioxidant capability and (3) cell apoptosis and AKT signaling within the ovary. After estrus synchronization, 24 Hu sheep were assigned to three groups based on the nutrient requirement recommended for maintenance (M): 1 x M (Control), 1.5 x M (S) and 0.5 x M (R) during days 7-14 of their estrous cycle. The results indicated that undernourishment significantly increased the counts and volume of follicles <2.5 mm and decreased the counts and volume of follicles ⩾2.5 mm (P < 0.05). Feed restriction altered the plasma and follicular redox balance within follicles ⩾2.5 mm by inhibiting total antioxidant capacity, increasing malondialdehyde concentration (P < 0.05) and reducing the mRNA expression levels of superoxide dismutase 2 (SOD2) and glutathione peroxidase (GSH-PX), as well as the activities of total SOD and GSH-PX. Feed restriction also attenuated B-cell lymphoma-2 (BCL2) but enhanced Bcl-2-associated X protein (BAX) and BAX/BCL2 transcription and translation levels in granulosa cells (P < 0.05). Uniform staining intensities of AKT and P-AKT-Ser473 were observed in each follicle stage, whereas weaker P-AKT-Thr308 staining in the antral follicle than in the pre-antral follicle suggested possible involvement of P-AKT-Thr308 during the beginning of follicle development. P-AKT-Ser473 levels in follicles ⩾2.5 mm was significantly reduced in the R group (P < 0.05). The results presented in this study demonstrate that suppressed folliculogenesis caused by feed restriction might be associated with attenuated AKT signaling, reduced follicular antioxidant capacity and enhanced granulosa cells apoptosis. [ABSTRACT FROM AUTHOR]

This study was conducted with an ovine intrauterine growth restriction (IUGR) model to test the hypothesis that dietary N-carbamylglutamate (NCG) and rumen-protected L-Arg (RP-Arg) supplementation are effective in ameliorating fetal growth restriction in undernourished ewes. Beginning on d 35 of gestation, ewes were fed a diet providing 100% of NRC-recommended nutrient requirements, 50% of NRC recommendations (50% NRC), 50% of NRC recommendations supplemented with 20 g/d RP-Arg (providing 10 g/d of Arg), and 50% of NRC recommendations supplemented with 5 g/d NCG product (providing 2.5 g/d of NCG). On d 110, maternal, fetal, and placental tissues and fluids were collected and weighed. Ewe weights were lower (P < 0.05) in nutrient-restricted ewes compared with adequately fed ewes. Maternal RP-Arg or NCG supplementation did not alter (P = 0.26) maternal BW in nutrient-restricted ewes. Weights of most fetal organs were increased (P < 0.05) in RP-Arg-treated and NCG-treated underfed ewes compared with 50% NRC-fed ewes. Supplementation of RP-Arg or NCG reduced (P < 0.05) concentrations of β-hydroxybutyrate, triglycerides, and ammonia in serum of underfed ewes but had no effect on concentrations of lactate and GH. Maternal RP-Arg or NCG supplementation markedly improved (P < 0.05) concentrations of AA (particularly arginine-family AA and branched-chain AA) and polyamines in maternal and fetal plasma and in fetal allantoic and amniotic fluids within nutrient-restricted ewes. These novel results indicate that dietary NCG and RP-Arg supplementation to underfed ewes ameliorated fetal growth restriction, at least in part, by increasing the availability of AA in the conceptus and provide support for its clinical use to ameliorate IUGR in humans and sheep industry production. [ABSTRACT FROM AUTHOR]

The corrosion behavior of a 304 oxide dispersion strengthened (ODS) austenitic stainless steel after being exposed to supercritical water (SCW) with dissolved oxygen of 300 ppb at 600 °C/25 MPa was studied. By the means of a least-square fit, the weight gain (Δ w) of the samples as a function of exposure time ( t) could be described by the equation Δ w = 8.011 × t0.459. An approximately parabolic time law in this specified SCW environment can be assumed. A triple protective oxide layer formed on the surface of the metal with the exposure time up to 1000 h. Furthermore, the result of slow-strain rate tensile (SSRT) test indicated that the 304-ODS austenitic stainless steel was not susceptible to stress corrosion cracking (SCC) in SCW at 600 °C/25 MPa. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells ( MDSCs), a heterogeneous population including myeloid progenitor and immature myeloid cells, are known to inhibit T cell responses. The issue of whether tumour-derived MDSCs regulate the immune response in an asthma environment is currently unclear. Here, we have reported that tumour-derived MDSCs shift the balance back to normal in a Th2-dominant asthmatic environment. In an ovalbumin ( OVA)-induced mouse asthma model, injected tumour-derived MDSCs were recruited to the lungs of asthmatic mice by CC chemokine ligand 2 ( CCL2). MDSCs transferred into asthmatic mice via i.v. injection suppressed the infiltration of inflammatory cells into the lung, the Th2 cytokine, IL-4, concentration in bronchial lavage fluid and the serum level of OVA-specific Ig E. Increased TGF- β1 production in the lung was detected after transfer of MDSCs. The inhibitory effects of MDSCs were reversed upon treatment with an anti- TGF- β1 antibody, suggesting dependence of these activities on TGF- β1. Our findings imply that tumour-derived MDSCs inhibit the Th2 cell-mediated response against allergen in a TGF- β1-dependent manner. Based on the collective results, we propose that asthma may be effectively targeted using a novel MDSC-based cell therapy approach. [ABSTRACT FROM AUTHOR]

Ovarian steroid hormones regulate follicular growth and atresia. This study aims to determine whether key ovarian sterol-regulatory genes are differentially expressed in Hu sheep under different short-term nutritional regimens. Estrus was synchronized using intravaginal progestagen sponges. The ewes were assigned randomly to 3 groups. On d 6 to 12 of their estrous cycle, the control (CON) group received a maintenance diet (1.0 x M), the supplemented (SUP) group received 1.5 x M, and the restricted (R) group received 0.5 x M. On d 7 to 12, blood samples were taken. The sheep were slaughtered at the end of the treatment, and their organs and ovaries were collected. The plasma concentrations of urea (P < 0.01), total cholesterol (P < 0.01), low-density lipoprotein cholesterol (P < 0.01), NEFA (P < 0.01), FSH (P < 0.05), and estradiol (P < 0.05) increased with decreasing dietary intake, whereas plasma triglyceride (P< 0.01) and triiodothyronine (T3) concentrations decreased (P < 0.05). The ewes in the R group had higher spleen weight and percentage of spleen to BW and lower liver and small intestine weights and percentage of liver/stomach to BW than the SUP group ewes {P < 0.05). Nutritional restriction decreased the cytochrome p450 (CYP17A1) and estrogen receptor 1 (ESRİ) mRNA expression (P < 0.05) and increased the cytochrome p450 aromatase 0CYP19A1) mRNA expression (P < 0.05) in follicles > 2.5 mm. Follicle size affected the mRNA expression of very low density lipoprotein receptor ( VLDLR), estrogen receptor 2 (ESR2), FSH receptor (FSHR), CYP17A1, and CYP19A1 {P < 0.05). In conclusion, we suggest that a potential mechanism by which short-term negative energy balance inhibits follicular growth may involve responses to disrupted reproductive hormone concentrations and influenced the intrafollicular expression of CYP17A1, CYP19A1, and ESRİ. This result may be due to increased plasma urea and lipid concentrations. [ABSTRACT FROM AUTHOR]

The authors present a novel compact wideband pattern-reconfigurable antenna with alternate reflector and radiator. The proposed antenna consists of a pair of step-shape patches, four switches and a coplanar waveguide feeding line. By setting the switches ON or OFF, the two step-shape patches can alternately switch between the radiator and the reflector. As a result, the proposed antenna is able to provide two-directional radiation patterns whose main beams are roughly directed in opposing directions from 3.7 to 6 GHz. Compared with other current pattern-reconfigurable antennas, the proposed antenna exhibits advantages of better back-to-front radiation ratio, more compact antenna size and wider operating band. In this investigation, the optimised size of the proposed antenna is 20 × 20 mm², which equates to 0.25 × 0.25λ²0 (λ0 is the wavelength at the low edge of the operating frequency band). In addition, the time-domain characteristics of the proposed antenna are presented and analysed. The antenna shows a good time-domain performance. Measured results are presented. [ABSTRACT FROM AUTHOR]

A 3D nonlinear flow-solid coupling model of simulating the propagation of hydraulic fracture in multilayered formation is proposed. The validation of the model is approved by simulating the fracturing process of a well in Daqing Oilfield, China. The influence of lithological parameters (in situ stress, elastic modulus, and tensile strength) on fracture configuration is studied. The results demonstrate that higher in situ stress, lower elastic modulus, and higher tensile strength of barrier zones will make the fracture height smaller. [ABSTRACT FROM PUBLISHER]

Summary: Eighteen months of daily consumption of milk containing 250 mg calcium prevented bone mineral density (BMD) loss at the hip and the femoral neck in postmenopausal Chinese women aged 45 to 65. Introduction: Estrogen-related bone loss in postmenopausal women can be prevented by the consumption of milk with high doses of calcium and soymilk with high doses of isoflavones. However, high doses of calcium and isoflavones may not be necessary to attain a beneficial effect of milk and soymilk on BMD. We hypothesized that BMD will increase in postmenopausal Chinese women who consume daily 250 mg calcium in milk or soymilk. Milk prevented bone loss at the hip and the femoral neck in postmenopausal Chinese women. Methods: A total of 141 eligible Chinese women without osteoporosis, aged 45-65, and postmenopausal for more than 2 years were randomized into groups receiving for 18 months (A) milk with 250 mg calcium daily, (B) soymilk with 250 mg calcium daily, or (C) neither milk nor soymilk. Dual-energy X-ray absorptiometry measured the BMD of the spine and hip at 0, 6, 12, and 18 months. Results: The BMD in the hip (2.52%) and the femoral neck (2.82%) of the women consuming milk was significantly higher (hip, P = 0.01; femoral neck, P < 0.0000001). The women in the control group experienced a reduction in BMD at all sites; the reduction in BMD was only significant at the hip during 12 months ( P = 0.008) and at the femoral neck during 18 months ( P = 0.005). Conclusions: Daily consumption of milk containing 250 mg calcium over 18 months prevents BMD loss at the hip and the femoral neck in postmenopausal Chinese women. [ABSTRACT FROM AUTHOR]

Magnesium diboride (MgB2) shows a wide application prospect in the field of low field DC application for its relatively simple structure and rather higher critical temperature than LTS. With the development of MgB2 composite superconductor manufacturing technology and cryogenic technology, developing conduction cooled superconducting MRI system with MgB2 composite superconductor is becoming increasingly feasible. An MgB2 superconducting magnet for MRI was developed. The MgB2 superconducting magnet is used to investigate the fundamental scientific problem of the MRI main magnet, including field uniformity and stability, influencing factors of MgB2 composite superconductor on field uniformity and stability. The superconducting magnet consists of 2 solenoids wound with MgB2 wire with the length of 60 m. The magnet has an outer diameter of 169 mm, an iron core diameter of 135 mm, and air gap of 32 mm. The superconducting magnet is fabricated and tested. The central magnetic field reaches 1.0 T when the current of the MgB2 magnet is 290 A. The central magnetic field is 0.39 T when the current of the MgB2 magnet is 100 A. In this paper, the minimum quench energy, the quench propagation velocity and the minimum propagation zone of the MgB2 composite conductor are measured. Main magnet for MRI with MgB2 composite superconductor is analysed and proposed, including magnet design and test results. By theoretical modeling and simulation, the detailed quench propagation of the magnet is further analysed. Finally, the stability criteria of conduction-cooled MRI magnet are established. [ABSTRACT FROM AUTHOR]

The critical performance of YBCO tape with inhomogeneous superconducting properties was simulated by use of a bad point distribution model and the Gaussian distribution model. The critical current and n value of the whole HTS tape was analysed. The reliability of the simulation was verified with the experimental data. The results of the two simulation models were compared each other. The influence of inhomogeneous properties on the critical performance of YBCO HTS tape was proved by simulation results which are helpful for the simulation of superconducting devices based on YBCO HTS tapes. [ABSTRACT FROM AUTHOR]

Magnesium diboride (MgB2) shows a wide application prospect in the field of low field DC application for its relatively simple structure and rather higher critical temperature than LTS. With the development of MgB2 composite superconductor manufacturing technology and cryogenic technology, developing conduction cooled superconducting MRI system with MgB2 composite superconductor is becoming increasingly feasible. An MgB2 superconducting magnet for MRI was developed. The MgB2 superconducting magnet is used to investigate the fundamental scientific problem of the MRI main magnet, including field uniformity and stability, influencing factors of MgB2 composite superconductor on field uniformity and stability. The superconducting magnet consists of 2 solenoids wound with MgB2 wire with the length of 60 m. The magnet has an outer diameter of 169 mm, an iron core diameter of 135 mm, and air gap of 32 mm. The superconducting magnet is fabricated and tested. The central magnetic field reaches 1.0 T when the current of the MgB2 magnet is 290 A. The central magnetic field is 0.39 T when the current of the MgB2 magnet is 100 A. In this paper, main magnet for MRI with MgB2 composite superconductor is analysed and proposed, including magnet design, test results, and field uniformity. [ABSTRACT FROM AUTHOR]

We discuss the symmetric smoothed particle hydrodynamics (SSPH) method for generating basis functions for a meshless method. It admits a larger class of kernel functions than some other methods, including the smoothed particle hydrodynamics (SPH), the modified smoothed particle hydrodynamics (MSPH), the reproducing kernel particle method (RKPM), and the moving least squares (MLS) methods. For finding kernel estimates of derivatives of a function, the SSPH method does not use derivatives of the kernel function while other methods do, instead the SSPH method uses basis functions different from those employed to approximate the function. It is shown that the SSPH method and the RKPM give the same value of the kernel estimate of a function but give different values of kernel estimates of derivatives of the function. Results computed for a sine function defined on a one-dimensional domain reveal that the L 2, the H 1 and the H 2 error norms of the kernel estimates of a function computed with the SSPH method are less than those found with the MSPH method. Whereas the L 2 and the H 2 norms of the error in the estimates computed with the SSPH method are less than those with the RKPM, the H 1 norm of the error in the RKPM estimate is slightly less than that found with the SSPH method. The error norms for a sample problem computed with six kernel functions show that their rates of convergence with an increase in the number of uniformly distributed particles are the same and their magnitudes are determined by two coefficients related to the decay rate of the kernel function. The revised super Gauss function has the smallest error norm and is recommended as a kernel function in the SSPH method. We use the revised super Gauss kernel function to find the displacement field in a linear elastic rectangular plate with a circular hole at its centroid and subjected to tensile loads on two opposite edges. Results given by the SSPH and the MSPH methods agree very well with the analytic solution of the problem. However, results computed with the SSPH method have smaller error norms than those obtained from the MSPH method indicating that the former will give a better solution than the latter. The SSPH method is also applied to study wave propagation in a linear elastic bar. [ABSTRACT FROM AUTHOR]

A novel band-notched ultra wide-band antenna with a coplanar parasitic elliptical patch in an elliptical ring is presented in this paper. Printed on a dielectric substrate of FR4 with relative permittivity of 4.4 and fed by a 50Ω microstrip line, the proposed monopole antenna demonstrate a 10 dB return loss bandwidth of 2.91–11.91 GHz, with a band-notched at 5.15–5.98 GHz band and good radiation patterns. The proposed antenna is utilize the coplanar parasitic elliptical patch to reject the frequency band (5.15–5.85 GHz) limited by IEEE802.11a and HIPERLAN/2. The parameters which affect the performance of the antenna in terms of its frequency domain characteristics are investigated in this paper. [ABSTRACT FROM AUTHOR]

Background: Although the prevalence of allergic asthma increased quickly in the past decade, the diagnostic criteria have not been well established. The aim of the present study was to explore whether stem cell factor (SCF), B cell-activating factor (BAFF), and cytokines interleukin (IL)-17 and IL-31 are usable parameters for the diagnosis of allergic asthmatics. Methods: Blood samples were collected from patients with allergic asthma, control patients, and healthy control subjects. The serum concentrations of SCF, BAFF, IL-17, and IL-31 were measured by enzyme-linked immunosorbent assay. The corresponding mRNA levels in peripheral blood mononuclear cells (PBMCs) were determined by real-time reverse-transcription polymerase chain reaction. Results: A good correlation existed between protein levels of SCF and IL-31 and their mRNA levels (SCF: r = 0.6162; IL-31: r = 0.5463). The serum concentrations of SCF and IL-31 in allergic asthmatic patients, but not control patients, were significantly higher than those in normal control subjects (SCF: median 1.83 vs 0.85 ng/ml, P < 0.01; IL-31: 50.15 vs 10.01 pg/ml, P < 0.001). Consistently, the levels of SCF and IL-31 mRNAs in allergic asthmatic patients’ PBMCs were also significantly higher than those in normal control subjects ( P = 0.002 and P < 0.001, respectively). Conclusions: These findings suggest that allergic asthma is characterized by an elevation of cytokines SCF and IL-31 and the measurement of their expression at either protein level in serum or mRNA level in PBMCs will be a valuable parameter for the diagnosis of allergic asthma. [ABSTRACT FROM AUTHOR]

In 2005, rose plants ( Rosa rugosa cv. ‘Plena’) exhibiting typical phytoplasma disease symptoms of stunting, yellowing, witches’-broom and dieback were observed in Pingyin, Shandong Province, China. The disease, rose witches’-broom (RoWB), is progressively destructive and can be graft-transmitted. Polymerase chain reaction (PCR), sequencing of PCR products and electron microscopy were used to investigate the possible association of phytoplasma with RoWB. All results indicated that presence of phytoplasma in the symptomatic rose plants. Sequence alignment of 16S rRNA gene, tuf gene and rp gene confirmed that the phytoplasma associated with RoWB is the causal agent of Paulownia witches’-broom disease, which might be transmitted from the paulownia tree that is several meters away. To our knowledge, this is the first report of the molecular characterization of phytoplasma infecting rose in China. [ABSTRACT FROM AUTHOR]

A novel dual-band design of planar monopole antenna is presented in this paper. Printed on a dielectric substrate and fed by a 50 Ω microstrip line, a planar monopole antenna is demonstrated to generate two separate resonant modes to cover 2.4/5.2 GHz WLAN (wireless local area network) bands with satisfactory radiation properties. The impedance bandwidths of the proposed antenna are 600 MHz centered at 2.65Hz and 1.15GHz centered at 5.12 GHz for S11 < -10 dB. The parameters which affect the performance of the antenna in terms of its frequency domain characteristics are investigated. [ABSTRACT FROM AUTHOR]

This paper presents a novel microstrip patch antenna for three-frequency and broad-band application, consisting of a 120 degree isosceles triangle with five stubs which are loaded at the bottom edge of the triangle. By adjusting lengths of these stubs, the antenna's operating frequency ratios can be tuned, and the three frequencies have the similar broadside radiation characteristics. Moreover, it is found that two separate resonate frequencies can be connected to increase bandwidth of the proposed antenna. [ABSTRACT FROM AUTHOR]

A coplanar waveguide-fed uniplanar multi-folded slot antenna that has impedance bandwidth enough to cover UWB systems is presented. The -10 dB return loss bandwidth of the antenna spans from about 3 GHz to about 11 GHz. Parametric study is presented. Details of the proposed ultra-wideband design are described and simulation results are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]

Novel dual-band and broad-band designs of a slot antenna with a cross-shaped stub are presented in this paper. For dual-band operation, the antenna's operating frequency ratio can be tuned by adjusting size of the cross-shaped stub. When proper design is achieved, the antenna can generate two separate resonant modes to cover 2.4/5.2 GHz (wireless local area network) WLAN bands. The simulated impedance bandwidths of the proposed antenna are 260 MHz centered at 2.44 GHz and 610 MHz centered at 5.36 GHz for S11 < -10 dB. Furthermore, it is found that two separate resonate frequencies can be connected to cover the frequency ranges of the digital communication system, personal communication system, international mobile telecommunication, and 2.4GHz WLAN. The bandwidth of the wideband antenna is 1.49 GHz centered at 2 GHz. Details of the proposed dual-frequency and broad-band designs are described and simulation results are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]

Conical carbon fibers (CCFs) with carbon nanotubes (CNTs) as their cores were grown on graphite substrates with a chemical vapor deposition method. The CNT-cored CCFs were about several tens of micrometers in length. In the interaction with a probe system, the CNT core filaments demonstrated good mechanical strength. Furthermore, field emission currents around 100 μA were also attained from individual CNTs. The growth mechanism of this CNT/CCF combined structure is briefly discussed. Our method has provided a convenient and inexpensive approach to mass assembling CNTs to a carbon substrate. [ABSTRACT FROM AUTHOR]

HTS materials can be used to develop novel permanent magnet (PM) motor. Based on the experimental and theoretical investigations, it was observed that the multi-impulse magnetization strategy should be selected for the constraints such as the temperature distributions and mechanical strength of the motor. The asymmetrical field distribution of HTS would induce torque ripples and unbalanced force. Proper cares have to be taken to avoid irreversible demagnetization. Resin impregnation and enclosing the rotor in a can/sleeve may provide the rotor enough mechanical strength to enable its high speed applications. [ABSTRACT FROM AUTHOR]

Total AC losses in multi-filamentary, silver-sheathed Bi2Sr2Ca2Cu3Oy (Bi-2223) tape were measured as functions of transport current, applied magnetic field and frequency by electromagnetic and calorimetric methods. Results of both methods agree well with each other. The calorimetric method was employed to investigate the effect of the phase difference between transport current and applied field, Δj on total AC loss. Total loss changes significantly with Δj when applied magnetic field is perpendicular to the surface of the sample. The effect of Δj on total loss in parallel magnetic applied field is smaller. [ABSTRACT FROM AUTHOR]

HTS bulks can be used as flux-focusing elements in reluctance motors. As parts of the primary study, a small prototype reluctance motor was designed and constructed by using HTS YBCO bulks. The performance was analyzed based on magnetic field calculation. An experimental investigation was carded out on the prototype motor. Computed parameters are compared with test measurements, showing good agreement. Compared with the conventional synchronous reluctance motors, higher efficiency and smaller size make these motors very attractive for the applications, such as cryogenic pumps and flywheel drives. [ABSTRACT FROM AUTHOR]

In-situ high-pressure energy dispersive X-ray diffraction measurements on CuBa2-Ca3Cu4O10+δ(Cu-1234) have been performed by using diamond anvil cell (DAC) device with synchrotron radiation. The results suggest that the crystal structure of Cu-1234 superconductor is stable under pressures up to 34 GPa at room temperature. According to the Birch-Murnaghan equation of state, the bulk modulus is obtained to be ∼150 GPa. [ABSTRACT FROM AUTHOR]

Single crystalline nanorods (15-200 nm in diameter and hundreds nanometers in length) have been formed on the carbon-covered W wires by simple electric heating under a vacuum of 5 × 10-4 Pa. The chemical composition and crystalline structure of the nanorods were carefully investigated by various characterization techniques such as scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, energy dispersive x-ray spectroscopy and electron energy loss spectroscopy. After ruling out any possible existence of carbon nanotubes (CNTs), tungsten carbide, W-Fe alloying, and formation of other types of tungsten oxides, monoclinic W18O49 phase has been well identified. The mechanism of nanorod formation of sub-tungsten oxide (∼WO2.7 compared to WO3) will be discussed in relation to the sample preparation conditions. [ABSTRACT FROM AUTHOR]

The solanum fruit fly,Bactrocera latifrons(Hendel), is a major agricultural pest in Asia and Hawaii, and it is important to prevent its widespread invasion in plant quarantine. In this study we introduced a real-time polymerase chain reaction (PCR) essay, using SYBR Green I dye, to rapidly identifyB. latifronson an ABI PRISM 7700 sequence detection system. A latifron-specific PCR primer set was obtained based on mtDNA COI gene ofB. latifrons. NineBactrocerafruit flies,B. latifrons,Bactrocera dorsalis,Bactrocera papayae,Bactrocera carambolae,Bactrocera philippinensis,Bactrocera occipitalis,Bactrocera correcta,Bactrocera cucurbitaeandBactrocera tau, were used to determine the specificity of primers lati1 and lati2. A series of genomic DNA dilutions ofB. latifrons(0.01, 0.1, 1, 10, 20, 40 and 100 ng) were used to assess the sensitivity of the SYBR Green PCR. Template DNA concentration was one of the sources of variability in cycle threshold values (CT) and the optimum DNA concentration was between 1 and 20 ng. Genomic DNA isolated from larvae, pupae and adult specimens ofB. latifronswere used to assess the specificity of the SYBR Green PCR. Melting curve analysis and agarose gel electrophoresis was employed to check the specificity of PCR products. Similar amplification plots were obtained using DNA from the three different stages ofB. latifronswith primer set lati1/lati2. The melting temperature (Tm) of PCR products was 77.5 ± 0.1°C, and the length of the amplified fragment 366 bp. Given the specificity and sensitivity of the assay, combined with high speed, low cost and the possibility of automating, SYBR Green PCR can be used as a rapid and specific technique for pest species identification in plant quarantine. [ABSTRACT FROM AUTHOR]

Control of nutrients as nitrogen and phosphorus after discharge into lakes is necessary since it is difficult and costly to control within wastewater plants currently in China. This paper studied the cycling of phosphorus and nitrogen with water and sediments from two lakes in China. It is found that oxygen plays a critical role in regulating phosphorus and nitrogen cycling within water and sediments. Three different oxygenation methods including aeration, calcium peroxide and hydrogen peroxide were studied to control phosphorus and nitrogen in overlying water. In anoxic conditions, the P concentration in water increased from an average 14 µg/L to 115.2 µg/L for Xili Lake, and from an average 24 µg/L to 1,000 µg/L for Jinchun Lake. The concentration of ammonia increased under anoxic conditions, while the concentration of nitrate increased under oxic conditions. In anoxic conditions, the nitrate concentration decreased probably through denitrification. Both N and P accumulation processes can be controlled under the three treatments. The phosphorus removal efficiency from the water body was in the order of CaO2 addition > aeration > H2O2 addition, while controlling effectiveness for ammonia was in the order of aeration > CaO2 addition > H2O2 addition. [ABSTRACT FROM AUTHOR]

A modification to the smoothed particle hydrodynamics method is proposed that improves the accuracy of the approximation especially at points near the boundary of the domain. The modified method is used to study one-dimensional wave propagation and two-dimensional transient heat conduction problems. [ABSTRACT FROM AUTHOR]

A site investigation was conducted to correlate the relationships between microcystins (MC) concentration and algal growth in Dianchi Lake in China. Laboratory experiments were undertaken to test the effects of sediment adsorption, photoirradiation and biodegradation on microcystins removal. Bioaccumulation of microcystins was also determined using silver carp fish. It was observed that MC concentrations varied in accordance with algae growth in Dianchi Lake. The results obtained in the laboratory demonstrated that the removal of MC with fresh sediments was less than 10%, photoirradiation removed more than 75% MC within two hours, and the biodegradation needed much longer time to produce substantial degradation of MC. The results suggest that bioaccumulation of microcystins in fish was not significant in Dianchi Lake. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate the distribution and variation of microcystins (MC) from a water resource to a water plant in China including long distance transportation, ClO2 preoxidation, coagulation/precipitation, filtration, and disinfection. Advanced treatment methods including ozonation and granular activated carbon (GAC) adsorption were tested to remove microcystins from drinking water. The results indicated that, when containing high level of algae in raw water, preoxidation at 2 mg/L of ClO2 was not enough to stop algae growth in long distance transportation. In the water plant studied, both coagulation and filtration caused significant increase instead of removal of microcystins in drinking water. Chlorine disinfection removed part of microcystins. However, both ozonation and GAC adsorption were able to remove microcystins completely, thereby improving the quality of drinking water in terms of microcystins. [ABSTRACT FROM AUTHOR]

A simulation model for theoretically studying the operation behavior of a rotary motor driven by surface acoustic waves (SAWs) is proposed. According to the model, some simulation results are obtained as follows: (1) as the rotor is excited by the SAWs, the motor experiences two phases, i.e., the acceleration phase and the steady phase; (2) the normal vibration amplitude A of SAWs has a very weak effect on the acceleration in the first phase but an enhancing effect on the steady velocity of the rotary motor; (3) as the number of the contact points between the rotor and the stator increases, the motor rotates more steadily; (4) as the rotor radius becomes smaller, both the acceleration and the steady angular velocity become greater. These features are in agreement with the experimental results. © 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The O(3) symmetric Anderson model is an example of a system which has a stable low energy marginal Fermi liquid fixed point for a certain choice of parameters. It is also exactly equivalent, in the large U limit, to a localized model which describes the spin degrees of freedom of the linear dispersion two channel Kondo model. We first use an argument based on conformal field theory to establish this precise equivalence with the two channel model. We then use the numerical renormalization group (NRG) approach to calculate both one-electron and two-electron response functions for a range of values of the interaction strength U. We compare the behaviours about the marginal Fermi liquid and Fermi liquid fixed points and interpret the results in terms of a renormalized Majorana fermion picture of the elementary excitations. In the marginal Fermi liquid case the spectral densities of all the Majorana fermion modes display a dependence on the lowest energy scale, and in addition the zero Majorana mode has a delta function contribution. The weight of this delta function is studied as a function of the interaction U and is found to decrease exponentially with U for large U. Using the equivalence with the two channel Kondo model in the large U limit, we deduce the dynamical spin susceptibility of the two channel Kondo model over the full frequency range. We use renormalized perturbation theory to interpret the results and to calculate the coefficient of the ln divergence found in the low frequency behaviour of the T=0 dynamic susceptibility. [ABSTRACT FROM AUTHOR]

Fuzzy methods in remote sensing have received growing interest for their particular value in situations where the geographical phenomena are inherently fuzzy. A fuzzy approach is investigated for the classification of sub-urban land cover from remote sensing imagery and the evaluation of classification accuracy. Under the fuzzy strategy, fuzziness, intrinsic to both remotely sensed data and ground data, is accommodated and usefully explored. For comparative purposes, hard and fuzzy classifications were produced and tested using hard and fuzzy evaluation techniques. The results show that the fuzzy approach holds advantages over both conventional hard methods and partially fuzzy approaches, in which fuzziness in only the remotely sensed imagery is accommodated. It was found that Kappa coefficients were more than doubled when applying the fuzzy evaluation technique as opposed to the hard evaluation technique. Furthermore, the fuzzy approach paves the way towards an integrated handling of remotely sensed data and other spatial data. [ABSTRACT FROM AUTHOR]

We report a giant resistance drop induced by dc electrical currents in La0.67Ca0.33MnO3 epitaxial thin films. Resistance of the patterned thin films decreases exponentially with increasing current and a maximum drop shows at the temperature of resistance peak Tp. Variation of resistance with current densities can be scaled below and above Tp, respectively. This work can be useful for the future applications of electroresistance. [ABSTRACT FROM AUTHOR]

An acoustic micro-imaging (AMI) technique for the evaluation of microelectronic packages and populated circuit boards is proposed. The technique is based on the concepts of sparse signal representation in overcomplete time-frequency dictionaries. The experimental results demonstrate its superior ability to conventional AMI techniques. [ABSTRACT FROM AUTHOR]