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Commercially available intravaginal progesterone (P4) devices differ in shape, surface area and P4 load, which may affect the resulting pregnancy per AI (P/AI) following timed-AI (TAI). The objective of this study was to compare two intravaginal P4 devices on estrus rate, follicular dynamics and P/AI in beef cattle subjected to shortened-TAI protocols. In Expt. 1, nulliparous heifers were randomly assigned to a P4-releasing intravaginal device (PRID-Delta, 1.55 g P4) or a controlled internal drug release (CIDR, 1.38 g P4) at the initiation of a J-synch protocol. Heifers that displayed estrus 72 h following device removal were TAI, or if not in estrus given GnRH at 72 h and TAI at 90 h. In Expt. 2, nulliparous heifers and non-suckling cows were randomly assigned to either PRID or CIDR groups and either 1 or 2 mg of estradiol benzoate (EB) at initiation of a J-synch protocol. All cattle were TAI concurrent with GnRH 72 h after device removal. In Expt. 3, nulliparous heifers and suckling cows were randomly assigned to either PRID or CIDR groups and initiated a 5-d Cosynch protocol, with TAI concurrent with GnRH 72 h following device removal. In each experiment, cattle received estrus detection patches at device removal, which were then scored from 0 to 3 based on color change between initial application and TAI; 0 = unchanged, 1 = ≤50% change, 2 = >50% change, 3 = missing. Estrus was defined to have occurred when the patch was scored 2 or 3. Transrectal ultrasonography was used to determine cyclicity, diagnose pregnancy in all experiments, and the size of the ovulatory follicle in Expt. 3. In Expt. 1, the estrus rate was greater (72.0% vs. 61.0%; P = 0.04) in the PRID compared to the CIDR group. In Expt. 2, a parity by EB dose interaction (P = 0.02) was attributed to an increased estrus rate (52.8% vs. 41.4%; P = 0.05) in heifers given 1 vs. 2 mg EB. In Expt. 3, there was no difference in the ovulatory follicle diameter at device removal (P = 0.22) or TAI (P = 0.28) between P4 groups. Treatment with a PRID tended (P = 0.10) to increase the P/AI in cows compared to a CIDR (73.5% vs. 61.0%). In all experiments combined, the overall P/AI tended to increase (55.2% vs. 51.0%; P = 0.08) and P/AI in cattle exhibiting estrus increased (64.4% vs. 59.7%; P = 0.02) in cattle given a PRID compared to those given a CIDR, respectively. In summary, the type of intravaginal P4 device affected estrus response and P/AI following TAI in beef cows.

The present work reports a study of the structural, elastic, dynamical and thermodynamic properties of rock salt (RS) LiCl within density functional theory. It is found that the lattice constant and elastic constants are in very good agreement with the other calculations or experimental values. The phonon dispersion curve along several high symmetry lines at the Brillouin zone (BZ) is determined using density functional perturbation theory (DFPT), and the phonon frequencies at the Γ point of the Brillouin zone are in reasonable agreement with previous calculations and experimental values. We also calculate the thermodynamic functions based on phonon density of states.

Heavy metal contamination of minesoils is a widespread problem in China. In Pingle manganese mineland in Guangxi (south China), heavy metal concentrations in soils and dominant plants were determined, and soil contamination was assessed with pollution index (Pi) and index of geoaccumulation (I-geo). Pi showed the minesoil was heavily polluted by Cd and slightly polluted by Cr. I-geo showed a severer pollution for all metals (except for Mn) than Pi because I-geo tended to overestimate the real pollution effect of minesoil. Fresh tailings dam had both the highest Pi and I-geo among the four sites indicating a high metal contamination. All the “bio-available” fractions of the studied metals were below 5% of the totals. Dominant plants tended to accumulate higher Cd and Cr, and showed higher Mn translocation to aboveground parts. Besides the agricultural reclamation, more diverse restoration goals with lower environmental risks should be considered for the Mn mine wastelands in South China.

This paper reports on a study to convert electrodeposited Tl-oxide films to Hg-1212 using the cation-exchange process. A two-layer electrodeposition process was used to prepare Tl–Ba–Ca–Cu–O films with Tl-1212 and Tl-2212 stoichiometry. Electrodeposited Tl-films were also deposited with Bi and Sr substituted for the Tl and Ba, respectively and also reacted using cation exchange to attempt formation of Hg-1212. The superconducting transition temperature for the “non-substituted” films improved from 97 to 120 K after the cation-exchange process with a critical current density exceeding 2×106 at 5 K in zero field. The cation-exchange process for the Bi, Sr substituted films appears to be more difficult with no marked improvement in superconducting properties.

Carbon nanotubes uniformly 50 nm in diameter were directly grown on graphite foil. Cyclic voltammetry (CV) shows that the carbon nanotube/graphite foil electrode has a high specific capacitance (115.7 F/g at a scan rate of 100 mV/s) and exhibits typical double-layer behavior. A rectangular-shaped CV curve persists even at a scan rate of 100 mV/s in 1.0 M H 2 SO 4 aqueous solution, which suggests that the carbon nanotube electrode could be an excellent candidate as the electrode in electrochemical double-layer capacitors. In addition, the influence of the potential scan rate, aging, and the electrolyte solution on the specific capacitance of nanotube electrodes was also studied.

Microstructures of Tl2Ba2CuO6 (Tl-2201) thin films with different doping levels grown on SrTiO3 substrates were studied by transmission electron microscopy. It is found that Tl-2201 films are epitaxial single phase over large area. A new three-dimensional modulation structure was observed for the heavily overdoped films. With decrease of doping level from heavily overdoped to optimally doped, the modulation structure becomes weaker and weaker and finally disappears at Tc of about 50 K. The structural symmetry of the optimally doped Tl-2201 films was confirmed to be tetragonal I4/mmm by convergent-beam electron diffraction. The tetragonal symmetry is broken into orthorhombic due to the modulation structure and consequently orthogonal twinning bands along 〈1 1 0〉 directions were observed. The modulation was found to be mainly localized in the CuO2 plane.

Polypyrrole (PPy) films were uniformly electropolymerized over each carbon nanotube of the well-aligned carbon nanotube arrays. For comparison, PPy films were also coated on flat metallic titanium (Ti) and platinum (Pt) substrates by the same technique. The synthesis and the redox performance of the PPy films were conducted by cyclic voltammetry (CV). The structural characterization including the thickness and uniformity of the PPy films was carried out by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is observed that the coating of the PPy film over carbon nanotubes is much faster than that on flat Ti/Pt surface. Furthermore, the redox performance of the PPy-coated carbon nanotube electrodes over flat Ti/Pt electrodes was significantly improved due to the high accessible surface area of the carbon nanotubes in the aligned arrays, especially in large film formation charge ( Q film ). It is very promising that the electrode developed in this study could be used as high performance electrode in rechargeable batteries.

Heavily overdoped epitaxial superconducting Tl 2 Ba 2 CuO 6+ δ (Tl-2201) thin films with single superconducting transition temperatures as low as 1.5 K (zero resistance) have been successfully synthesized. The films were made by “off-axis” radiofrequency magnetron sputtering and post-deposition annealing with slow cooling. Our investigations showed that the achievement of a single transition can be attributed to an off-axis configuration during sputter deposition, whereas the reduced T c results from a slow-cooling process immediately after annealing at high temperature. Transmission electron microscopy reveals that the films are pure 2201 phase with good crystallinity and modulated structure. Such samples are very much desired for detailed investigations of upper critical magnetic fields using conventional laboratory superconducting magnets, or the dc facilities at National Laboratories.

Carbon nanotubes have been synthesized by chemical vapor deposition on graphite foil coated with stainless steel film as catalyst by magnetron sputtering. Annealing in hydrogen was used to convert the stainless steel film to the needed catalyst particles that have a different composition from the initial stainless steel film due to phase segregation during annealing. The catalyst particle size increases with the increase of the initial stainless steel film thickness. The outer diameter of the carbon nanotubes increases dramatically with catalyst particle size, whereas the inner diameter increases slightly first then remains roughly constant at about 7 nm.

We report on developing a two-layer process to deposit biaxially textured Tl-oxide films by electrodeposition (ED) on Ag-coated, single-crystal substrates. Pole-figure measurements of two-layer, electrodeposited (Tl,Bi)–(Sr,Ba)–Ca–Cu–O (TBSBCCO) films on 300 A Ag/LaAlO 3 (LAO), with thickness between 1 and 5 μm, clearly show strong biaxial texturing. The omega scan and phi scan of 1.6 μm (TlBi) 0.9 Sr 1.6 Ba 0.4 Ca 2 Cu 3 Ag 0.2 O x films indicate the full width at half maximum (FWHM) of only 0.92° and 0.6°, respectively, indicating a very high-quality film prepared by the ED process. Transport measurements for the electrodeposited, thallium-oxide-based superconductor films show values above 10 6 A/cm 2 at 77 K in zero field.

Epitaxial (Tl,Bi)Sr 2 Cr 0.15 Ca 0.85 Cu 2 O y [(Tl,Bi)-1212] films have been successfully grown on both LaAlO 3 and CeO 2 /YSZ substrates by post-deposition annealing in flowing argon gas. These superconducting Tl-based, 1212-structured films on LaAlO 3 substrates have T c values in the range of 94–100 K, and J c values over 1.0×10 6 A/cm 2 at 77 K. The films are predominately 1212 phase, with excellent epitaxy as determined by XRD θ –2 θ , ω and φ scans. The films on CeO 2 /YSZ substrates have T c values in the range of 94–96 K, J c (77 K) values close to 6×10 5 A/cm 2 and excellent epitaxy on the CeO 2 buffer layers.

Growth of epitaxial Cr-doped (Tl,Bi)-1212 films on LaAlO3 substrates by pulsed laser deposition (PLD) and post-deposition annealing in static air has been achieved. The films exhibit a high transport Jc of over 1.5 × 106 A cm-2 at 77 K and self-field. Tc values measured by the four-probe method are in the range 94-100 K. ICP emission spectroscopy measurement shows a thallium deficiency, with about 0.15 atom bismuth per formula in the film. XRD -2 , and scans show that the dominant phase is 1212, with excellent epitaxy. The film surface has typical PLD morphology as analysed by SEM. TEM analysis found some inclusions in the film, and HREM found that three 1201 layers exist between the interface of 1212 phase and substrate.

The Xiangxi Au–Sb–W deposit, the largest of its type in northwestern Hunan, China, is a sulfide-dominated ore body hosted by low grade metamorphic red slates of the Neoproterozoic Madiyi Formation. Three stages of mineralization, quartz–scheelite, quartz–gold–pyrite, quartz–gold–stibnite, and one metal-barren stage of veining, quartz–calcite, are recognized. Arsenopyrite occurs only as a minor mineral phase in the second stage. Analyses for 21 trace elements show that the enrichment factors of As in the metal deposit (EC [=element concentration of sample/average content of an element in the upper crust]: 190; 43 samples) in ore veins and in the Guanzhuang and Yuershan reference sections (3.7 km and 2.7 km away from the Xiangxi mine, EC: 3.5; 96 samples) are much smaller than those of Sb (52855 [in ore veins], 117 [in the sections]), W (5665, 7.5) and Au (2727, 5.3). The background concentrations of Au and As in the two sections were 1.4 ppb and 1.4 ppm, respectively. Arsenic (with an anomaly coefficient [AC = number of anomalous samples/total number of samples] of 76%) forms a larger geochemical halo than W (AC: 8%) and Au (AC: 32%). Gold and As in the deposit were transported mainly as metal complexes such as Au(HS)−2, HnAs3S−(3−n)6 (n=1, 2 or 3) and HAsS02. Au(HS)−2 is rapidly precipitated by a geochemical oxidation barrier — the red slates of the Madiyi Formation. As–S complexes in the stratigraphic horizon can be transformed into As–O complexes (e.g., H3AsO03) under oxidizing conditions, and are continuously transported. Therefore, they can be widely distributed in the red slate units, thus forming extensive geochemical haloes, so that As can be used as an indicator element for Au exploration in the Xiangxi region.

In China, a great number of Au–(Sb–W) deposits or mineralizations are located in NW Hunan. The Xiangxi deposit is the largest and, as 80% of such metal accumulations in this region, occurs in the late Proterozoic—low grade metamorphic red slate Madiyi Formation. Ore bodies of the Xiangxi Mining District are strictly structurally controlled. Gold, antimony, tungsten, and arsenic are strongly concentrated relative to bed rock lithologies. Sulfur, Hg, Mo, and locally Cu, Pb, and Zn are weakly enriched only. The Madiyi Formation was deposited under oxidizing conditions in a shallow marine environment, and is characterized by a high Fe2O3 content, with local accumulations of CaO. The stratigraphic horizon is probably not a source-bed for the Au, Sb, and W mineralizations in this region. High contents of these elements and As were likely introduced by hydrothermal fluids. Background values for Au, Sb, W, and As in the Madiyi Formation are 1.4 ppb, 0.42 ppm, 1.9 ppm, and 1.4 ppm, respectively. The stratigraphic sequence acts as a geochemical barrier controlling the distribution of Au (or/and Sb–W).

The utility of glass carbon electrode modified with Nafion for the cathodic stripping voltammetric determination of iron (III) is demonstrated. The method is based on the formation of the Fe(III) and αα-bipyridine complex, which is preconcentrated by a Nafion-modified electrode at +0.75V (vs Ag-AgCl). A stripping scan is carried out from +0.75 to −0.10 V at 100 mV/s scan rate. The favorable concentration of the base solution contains 0.02 mol/liter LiCl, 0.03 mol/liter HCL, and 1.0 × 10−5 mol/liter αα-bipyridine (pH 2.5). Under the optimal conditions, the peak current is proportional to Fe(III) concentration in the range of 0.05-2.0 ng/ml (2 min preconcentration time). The method has been used to determine iron in fountain water and longan with satisfactory results.

Polypyrrole/carbon nanotube nanoscale composites were successfully fabricated by electrochemical deposition of polypyrrole over each of the carbon nanotubes in well-aligned large arrays. The thickness of the polypyrrole coating can be easily controlled by the value of the film-formation charge. For both thin (low film-formation charge) and thick (high film-formation charge) films, the polypyrrole coating on the surface of each nanotube is very uniform throughout the entire length, as observed by transmission electron microscopy.

Foodborne infections are a significant cause of morbidity and mortality in human populations. Risk assessment and public health control measures could be greatly enhanced by establishing an accurate relationship between ingested dose and infection, and defining minimum infectious doses. In this paper, a novel neural network model is proposed for the dose response of foodborne pathogens. The proposed model assumes a three-layer structure with a fast backpropagation learning algorithm. The model predictions for four available data sets from the literature are compared using six statistical models (log-normal, log-logistic, simple exponential, flexible exponential, /spl beta/-Poisson and Weibull-Gamma). The methods of least square error, maximum likelihood and correlation coefficient are used for the comparison, and they show that the neural network model does better than the statistical models. Predictions of dose response for multiple types of pathogens and with different host age and gender using neural network models are discussed, with simulations.

It is observed that, in the total variation model for image deblurring, if the regularisation term simply involves the first-order difference, details cannot be satisfactorily restored in a deblurred image. A weighted difference as the total variation regularisation term is considered, and the related half-quadratic model is solved to obtain a deblurring algorithm for saving more details and highlighting the edges of an image. The effectiveness of the proposed algorithm is tested by deblurring experiments.