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In order to explore a breeding method for mycoplasmal pneumonia-negative swine population, the purifying effects of combination therapy, SEW and three-point breeding and management system on Mycoplasma hyopneumoniae were investigated in this study. After the processes of screening pregnant sows, programmed therapy for sows, SEW, three-point breeding and management in the barrier isolation system and programmed therapy for piglets, the newly-bred piglets were monitored as long as four months by serum antibody detection of Mycoplasma hyopneumoniae and fluorescent quantitative PCR of nose swabs. The results showed that when the newly-bred five batches of piglets were older than 35 d, they were all negative by serum antibody detection and nose swab antigen detection. Therefore, the combination therapy, SEW and three-point production and management system can effectively purify Mycoplasma hyopneumon-ae, providing theoretical basis and clinical experience for the control and purification of domestic mycoplasmal pneumonia. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To discover anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) microbial natural products or their derivatives. Method: Azalomycin F5a (1) was prepared through fermentation of Streptomyces hygroscopicus var. azalomyceticus, and its derivatives were synthesized through hydrocarbylation in hydrocarbyl alcoholic-AcOH (4 : 1) and subsequent demalonylation with 2 mol·L−1 KOH in MeOH-H2O (7 : 3). Their activities against MRSA ATCC 33592 and three clinical MRSA isolates were evaluated by the agar diffusion and broth microdilution methods. Results: Four demalonylazalomycin F5a derivatives 2 to 5 were synthesized. The anti-MRSA activity assay indicated that compounds 1 to 5 showed remarkable activity against MRSA, and their minimum inhibitory concentrations (MICs) were respectively 3.0–4.0, 0.5–1.0, 0.67–1.0, 0.67–0.83, and 0.5–0.83 μg·mL−1. Conclusion: Azalomycin F5a and the demalonylazalomycin F5a derivatives 2–5 showed remarkable anti-MRSA activity, and the anti-MRSA activities of 2 to 5 were higher than that of 1, while the anti-MRSA activities of 2 to 5 showed no obvious differences. It was also shown that the malonyl monoester group of azalomycin F5a was less important for its anti-MRSA activity. [Copyright &y& Elsevier]

We have studied the time-dependence degradation of ON current of amorphous silicon thin-film transistors (a-Si:H TFTs), which is a function of stress duration, stress temperature, and stress bias. A simple method with stretched-exponential equation and current-voltage function is used to characterize and predict the TFT performance. Bias-temperature stress at different stress voltages has been performed on a-Si:H TFTs. A new method using ON current degradation to analyze TFT device performance is presented, which is different from the conventional threshold-voltage shift method. We have also observed that the beta value in the ON current degradation method compared to the threshold-voltage shift method, with a stretched-exponential stress time, is related to beta~beta0-TST/T0. Finally, we have also used the new equation to evaluate the performance of the gate-driver-on-array circuit in our products. If the limitation of the current for the pull-down device is 1times10-6 A, then the operation time of the pull-down device can be estimated to about 1219 h when key pulled-down TFT is operating at 60degC. [ABSTRACT FROM PUBLISHER]

In view of problem of big error between adjustment speed and expected speed of existing multistage belt speed-regualtion system adopting two-dimensional fuzzy control algorithm, a kind of adaptive neural fuzzy inference system (ANFIS) model was established, and a multistage belt speed-regualtion system based on ANFIS was designed. The speed-regualtion system takes instantaneous flow and real-time speed of the first belt as input, and takes regulating frequency of frequency converter as output to realize speed control. The Matlab simulation results show that the speed control error of the speed-regualtion system introducing ANFIS model is below 2%, capacity and belt speed matching rate are optimized, which has certain application value for energy saving and emission reduction of coal mine enterprises.

In this letter, the authors introduce a novel self-aligned etch-stopper sidewall-contact hydrogenated amorphous silicon (a-Si : H) thin-film transistor (ESSC-TFT), which reduces the photo leakage current by more than one order of magnitude and increases the ON-OFF ratio to seven orders of magnitude under back light illumination. Such a TFT will enable high-resolution and high-brightness liquid-crystal displays (LCDs) for next-generation TV, monitor, notebook, and mobile-phone applications. This ESSC-TFT design reduces the volume of a-Si film in which the active region can totally be shielded by the gate metal resulting in the prevention from direct back light illumination. With the sidewall contact, the hole current is reduced due to the smaller contact area between drain/source and a-Si layer. As well as the source, drain parasitic intrinsic resistance of a-Si can be also lessened by the ESSC-TFT structure. Although the defects between etched a-Si and n+ a-Si film may degrade the ON current, the ESSC-TFT still exhibits higher ON-OFF ratio and lower leakage than the one in traditional etch-stopper (ES)-TFT structure. The ESSC-TFT structure can be used not only for TFT-LCD application but also for the applications that demand high ON-OFF ratio and low-leakage device, such as X-ray image sensor. [ABSTRACT FROM AUTHOR]

Recently, the layered transition metal dichalcogenide 1T′ MoTe2 has attracted considerable attention due to its non-saturating magnetoresistance, type-II Weyl semimetal properties, superconductivity, and potential candidate for two-dimensional (2D) topological insulator in the single- and few-layer limit. Here in this work, we perform systematic transport measurements on thin flakes of MoTe2 prepared by mechanical exfoliation. We find that MoTe2 flakes are superconducting and have an onset superconducting transition temperature Tc up to 5.3 K, which significantly exceeds that of its bulk counterpart. The in-plane upper critical field (Hc2||) is much higher than the Pauli paramagnetic limit, implying that the MoTe2 flakes have Zeeman-protected Ising superconductivity. Furthermore, the Tc and Hc2 can be tuned by up to 320 mK and 400 mT by applying a gate voltage. Our result indicates that MoTe2 flake is a good candidate for studying exotic superconductivity with nontrivial topological properties. [ABSTRACT FROM AUTHOR]

ObjectiveTo explore the correlation between platelet-to-lymphocyte ratio (PLR) and failed treatment in patients with peritoneal dialysis-associated peritonitis (PDAP).MethodsFrom January 2018 to October 2022, 136 hospitalized patients fulfilling the clinical diagnostic criteria of PDAP were selected as study subjects. Demographic profiles, clinical examinations and laboratory parameters were recorded. They were assigned into two groups of successful treatment and failed treatment. General profiles and relevant clinical data of two groups were compared. The relationship between PLR and failed treatment of PDAP was examined by multivariate Logistic regression analysis. And receiver operating characteristic (ROC) curve was plotted for examining the predictive value of PLR on failed treatment of PDAP.ResultsA total of 221 bouts of PDAP occurred in 136 PD patients. As compared with successful treatment group, the levels of PLR[（472 ± 296） vs （232 ± 106）], NLR[（15.40 ± 11.20） vs （7.49 ± 5.92）] and platelet[（256 ± 92）×109/L vs （ 216 ± 84）×109/L] spiked markedly in failed treatment group. There were statistically significant differences (P

Single-layered zirconium pentatelluride (ZrTe5) has been predicted to be a large-gap two-dimensional (2D) topological insulator, which has attracted particular attention in topological phase transitions and potential device applications. Herein, we investigated the transport properties in ZrTe5 films as a function of thickness, ranging from a few nm to several hundred nm. We determined that the temperature of the resistivity anomaly peak (Tp) tends to increase as the thickness decreases. Moreover, at a critical thickness of ∼40 nm, the dominating carriers in the films change from n-type to p-type. A comprehensive investigation of Shubnikov–de Hass (SdH) oscillations and Hall resistance at variable temperatures revealed a multi-carrier transport tendency in the thin films. We determined the carrier densities and mobilities of two majority carriers using the simplified two-carrier model. The electron carriers can be attributed to the Dirac band with a non-trivial Berry phase π, while the hole carriers may originate from surface chemical reaction or unintentional doping during the microfabrication process. It is necessary to encapsulate the ZrTe5 film in an inert or vacuum environment to potentially achieve a substantial improvement in device quality. [ABSTRACT FROM AUTHOR]

Five fungal endophytes (K4, K5, K6, K9, K14) producing Cajaninstilbene acid (CSA, 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid) were isolated from the roots of pigeon pea [Cajanus cajan (L.) Millsp.]. CSA is responsible for the prominent pharmacological activities in pigeon pea. The amount of CSA in culture solution varied among the five fungal endophytes. K4 produced the highest levels of CSA (1037.13 µg/L) among the endophytes tested after incubation for five days. Both morphological characteristics and molecular methods were used for species identification of fungal endophytes. The five endophytic isolates were characterized by analyzing the internal transcribed spacer (ITS) rRNA and β-tubulin genes. The K4, K5, K9 and K14 strains isolated from pigeon pea roots were found to be closely related to the species Fusarium oxysporum. K6 was identified as Neonectria macrodidym. The present study is the first report on the isolation and identification of fungal endophytes producing CSA in pigeon pea. The study also provides a scientific base for large scale production of CSA.

We have combined elastic and inelastic neutron scattering techniques, magnetic susceptibility, and resistivity measurements to study single-crystal samples of Kx Fe2-ySe2, which contain the superconducting phase that has a transition temperature of ~31 K. In the inelastic neutron scattering measurements, we observe both the spin-wave excitations resulting from the block antiferromagnetic ordered phase and the resonance that is associated with the superconductivity in the superconducting phase, demonstrating the coexistence of these two orders. From the temperature dependence of the intensity of the magnetic Bragg peaks, we find that well before entering the superconducting state, the development of the magnetic order is interrupted, at ~42 K. We consider this result to be evidence for the physical separation of the antiferromagnetic and superconducting phases; the suppression is possibly due to the proximity effect of the superconducting fluctuations on the antiferromagnetic order. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the effects of different concentrations of preservatives on storage quality of orah fruits, so as to reduce the use of preservatives during its planting. Methods: The weight loss rate, vitamin C content, soluble solid content and titratable acid content of fruits were determined under different storage conditions, by using different concentrations of preservative. Results: At 4 ℃ and room temperature, the weight loss rate of fruits treated with preservatives was lower than that of the control group, and preservative treatment had different fresh-keeping effects on orah fruits. At 4 ℃, significant differences in vitamin C content among different treatments at 5, 28 and 42 days of storage were found, but no significant differences in other storage time. No significant difference in soluble solids and titratable acid contents among different treatments appeared. Among the treatment groups (treatment 1, treatment 2 and treatment 3), the weight loss rate, vitamin C content, soluble solid content and titratable acid content of orah fruit in treatment 2 were better than those in treatment 1 and 3. At room temperature, vitamin C content was significantly different among different treatments on the third day of storage. After 14 days of storage, the soluble solid content of treatment groups 1 and 2 was significantly different. On the 14th day of storage time, titratable acid content in treatment group 2 was significantly higher than that in treatment group 3. The contents of vitamin C, soluble solids and titratable acid in treatment group 2 were higher than those in other treatment groups, during most storage time. Conclusion: At 4 ℃, each preservative treatment has different degrees of preservation effect on orah fruits. 450 g/L midazamine +500 g/kg statin +100 g/kg 2,4-D+400 g/kg bellkute has better preservation effect on orah fruit.

We have performed systematic resistivity and inelastic neutron scattering measurements on Fe0.98 -zNizTe0.5Se0.5 samples to study the impact of Ni substitution on the transport properties and the low-energy (⩽12 meV) magnetic excitations. It is found that, with increasing Ni doping, both the conductivity and superconductivity are gradually suppressed; in contrast, the low-energy magnetic spectral weight changes little. Comparing with the impact of Co and Cu substitution, we find that the effects on conductivity and superconductivity for the same degree of substitution grow systematically as the atomic number of the substituent deviates from that of Fe. The impact of the substituents as scattering centers appears to be greater than any contribution to carrier concentration. The fact that low-energy magnetic spectral weight is not reduced by increased electron scattering indicates that the existence of antiferromagnetic correlations does not depend on electronic states close to the Fermi energy. [ABSTRACT FROM AUTHOR]

Currently available ELISAs used to diagnose Mycoplasma hyopneumoniae infection in pigs have high specificity but low sensitivity. To develop more sensitive assays, the kinetics of specific serum IgG and respiratory mucosal sIgA responses against three M. hyopneumoniae antigens, namely, P97R1 (an adhesin protein), P46 (a membrane protein), and P36 (a cytosolic protein), were characterised over 133 days following experimental infection. Immunoglobulin G against the three proteins remained at high concentrations from 28 to 133 days post-infection (dpi), although IgG against P97R1 was detected earlier and was more reactive than the other two antigens under assessment. Mucosal sIgA appeared earlier than serum IgG but did not persist as long; sIgA concentrations against P97R1 were the highest. Seroconversion was detected 2 weeks earlier with the P97R1-based ELISA than with a commercially available ELISA. On analysis of serum samples from five pig farms that did not use a M. hyopneumoniae vaccine, the P97R1-based IgG ELISA demonstrated a 73.6% coincidence rate with the commercial kit. Moreover, this more specific P97R1-based ELISA detected more positive samples than the commercial kit (52.8% vs. 39.2%). It was concluded that the systemic immune response to M. hyopneumoniae infection in pigs was delayed in onset but persistent whereas the mucosal response developed more rapidly but was less sustained. The P97R1 antigen was identified as a suitable serological marker for diagnosing M. hyopneumoniae infection in pigs, particularly early stage infection. [ABSTRACT FROM AUTHOR]

An attenuated Mycoplasma hyopneumoniae vaccine that requires intrathoracic administration is commercially available for use against mycoplasmal pneumonia in China. Given the limitations of such a route of administration, this study was undertaken to assess the capacity of an ISCOM-matrix adjuvant to enhance immunogenicity following intramuscular use. Immune responses in pigs following vaccination and subsequent intra-tracheal bacterial inoculation were examined using lymphocyte proliferation, serology and mucosal IgA in both nasal and saliva swabs. Vaccination induced clear lymphocyte proliferation, but only slight serum antibody responses although these were significantly increased following experimental infection. Mucosal IgA was not detected in either nasal or salivary secretions. Following bacterial challenge, animals vaccinated with the adjuvant-containing live vaccine exhibited less severe pulmonary lesions (median score 3.67) than unvaccinated pigs (median score 13.58). The degree of ciliary loss on the respiratory tract surface was reduced in vaccinated pigs compared with experimentally infected controls. The findings indicated that the adjuvant vaccine administered IM provided protection against experimentally induced mycoplasmal pneumonia and could have commercial potential. [ABSTRACT FROM AUTHOR]

Kitaev interactions underlying a quantum spin liquid have long been sought, but experimental data from which their strengths can be determined directly, are still lacking. Here, by carrying out inelastic neutron scattering measurements on high-quality single crystals of α-RuCl3, we observe spin-wave spectra with a gap of ~2 meV around the M point of the two-dimensional Brillouin zone. We derive an effective-spin model in the strong-coupling limit based on energy bands obtained from first-principles calculations, and find that the anisotropic Kitaev interaction K term and the isotropic antiferromagnetic off-diagonal exchange interaction Γ term are significantly larger than the Heisenberg exchange coupling J term. Our experimental data can be well fit using an effective-spin model with K=-6.8 meV and Γ=9.5 meV. These results demonstrate explicitly that Kitaev physics is realized in real materials. [ABSTRACT FROM AUTHOR]

Surface reactivity is important in modifying the physical and chemical properties of surface-sensitive materials, such as the topological insulators. Even though many studies addressing the reactivity of topological insulators towards external gases have been reported, it is still under heavy debate whether and how the topological insulators react with H2O. Here, we employ scanning tunneling microscopy to directly probe the surface reaction of Bi2Te3 towards H2O. Surprisingly, it is found that only the top quintuple layer is reactive to H2O, resulting in a hydrated Bi bilayer as well as some Bi islands, which passivate the surface and prevent subsequent reaction. A reaction mechanism is proposed with H2Te and hydrated Bi as the products. Unexpectedly, our study indicates that the reaction with water is intrinsic and not dependent on any surface defects. Since water inevitably exists, these findings provide key information when considering the reactions of Bi2Te3 with residual gases or atmosphere. [ABSTRACT FROM AUTHOR]

To enhance the integration and practical applicability of the Raman detection system, silver nanocubes (Ag NCs) were synthesized using a polyol method. A liquid-liquid interface approach was employed to transfer a monolayer of Ag NCs "film" onto a SiO 2 substrate, resulting in the fabrication of a highly sensitive and uniform surface-enhanced Raman scattering (SERS) substrate denoted as "Ag NCs@SiO 2 ." The electromagnetic field distribution of various dimers on the Ag NCs@SiO 2 was analyzed using finite difference time domain (FDTD) software. The results reveal that the electromagnetic enhancement effect is most pronounced in cube-cube dimers, indicating that Ag NCs exhibit superior localized surface plasmon resonance (LSPR) response due to their well-defined geometric regularity and sharp geometric angles. For Rhodamine 6G (R6G) probe molecules, the Ag NCs@SiO 2 shows ultrahigh sensitivity, with a limit of detection (LOD) of 10 -12  mol/L, and the enhancement factor (EF) can reach 1.4 × 10 10 . The relative standard deviation (RSD) at the main characteristic peaks is below 10%, demonstrating good consistency in substrate performance. In addition, the Ag NCs@SiO 2 modified with hexanethiol exhibits high sensitivity, uniformity, and repeatability in detecting for pyrene, with the LOD of 10 -8  mol/L and a minimum RSD of 6.09% at the main characteristic peak, and effective recognition capabilities for pyrene and anthracene in mixed solutions. Finally, chemisorption and physisorption strategies were prepared in optofluidic channels and experimentally compared, enabling real-time detection of the pyrene solution. This method can achieve a rapid detection and precise differentiation of polycyclic aromatic hydrocarbons in a water pollutant.

In this paper, we proposed a novel approach for rapid and flexible fabrication of self-driven microfluidic surface enhanced Raman scattering (SERS) chips for quantitative analysis of Hg 2+ by femtosecond laser direct writing. In contrast to traditional microfluidic chips, the microchannels of the device can drive a liquid sample flow without external driving force. The sample flow speed is tunable since the wettability and capillarity properties of the channels, which depend on the roughness and the inner diameter of the microchannels, can be controlled by optimizing the laser processing parameters. The SERS active detection sites, which exhibit high enhancement effects and fine reproducibility, were integrated through the femtosecond laser-induced periodic surface structures (LIPSS), followed by 30 nm Ag deposition. The SERS performance of the as-prepared microfluidic SERS detection chip was studied with R6G as probe molecules. The quantitative analysis of Hg 2+ was realized by simply injecting the Hg 2+ sample and the probe molecules R6G from the two inlets, separately, and collecting the SERS signal at the detection site. The lowest detection limit for Hg 2+ is 10 -9 M. It should be mentioned that this study is not only limited to Hg 2+ quantitative analysis, but is also mainly aimed to develop a new technique for the design and fabrication of novel self-driven microfluidic devices depending on practical application requirements.

Objective: To determine the prevalence and subtypes of Blastocystis in pet dogs in Anhui and Zhejiang Provinces., Methods: Pet dog fecal samples were collected from veterinary clinics in Baohe District of Hefei City, Xuanzhou District of Xuancheng City, Fengyang County and Mingguang City of Chuzhou City, Longzihu District of Bengbu City, Si County of Suzhou City in Anhui Province, as well as in Yuhang District of Hangzhou City in Zhejiang Province from April to December, 2013. Blastocystis was detected by microscopic examination as well as nested PCR and single-step PCR based on small subunit ribosomal DNA sequences. The PCR products were sequenced, and Blastocystis subtypes were assigned., Results: A total of 315 pet dog fecal samples were collected. The incidence of Blastocystis infection determined by microscopic examination, nested PCR and single-step PCR was 1.3%（4/315）, 1.9%（6/315） and 1.9%（6/315）, respectively. In addition, the two PCR methods both revealed Blastocystis infection only in Chuzhou City（3.4%, 1/29） and Hefei City（5.6%, 4/72）. The pet dogs in Chuzhou City carried ST1 and ST2 subtypes while those in Hefei carried only ST1. There was no significant difference in infection rate between adult and young dogs and between male and female dogs., Conclusion: Blastocystis infection exists in pet dogs in Chuzhou City and Hefei City.