Oxide Derivatives of Nb2CTx MXene and Their Application as Electron Transport Layers in Perovskite Solar Cells: Unraveling the Oxidation Process and Functionalization.

In the realm of photovoltaic research, 2D transition metal carbides (MXenes) have gained significant interest due to their exceptional photoelectric capabilities. However, the instability of MXenes due to oxidation has a direct impact on their practical applications. In this work, the oxidation process of Nb2CTx MXene in aqueous systems is methodically simulated at the atomic level and nanosecond timescales, which elucidates the structural variations influenced by the synergistic effects of water and dissolved oxygen, predicting a transition from metal to semiconductor with 44% C atoms replaced by O atoms in Nb2CTx. Moreover, Nb2CTx with varying oxidation degrees is utilized as electron transport layers (ETLs) in perovskite solar cells (PSCs). Favorable energy level alignments with superior electron transfer capability are achieved by controlled oxidation. By further exploring the composites of Nb2CTx to its derivatives, the strong interaction of the nano-composites is demonstrated to be more effective for electron transport, thus the corresponding PSC achieves a better performance with long-term stability compared with the widely used ETLs like SnO2. This work unravels the oxidation dynamics of Nb2CTx and provides a promising approach to designing ETL by exploiting MXenes to their derivatives for photovoltaic technologies.

Ultrahigh Detectivity Broad Spectrum UV Photodetector with Rapid Response Speed Based on p-ß Ga2 O3 /n-GaN Heterojunction Fabricated by a Reversed Substitution Doping Method.

An excellent broad-spectrum (220-380 nm) UV photodetector, covering the UVA-UVC wavelength range, with an ultrahigh detectivity of ≈1015  cm Hz1/2 W-1 , is reported. It is based on a p-ß Ga2 O3 /n-GaN heterojunction, in which p-ß Ga2 O3 is synthesized by thermal oxidation of GaN and a heterostructure is constructed with the bottom n-GaN. XRD shows the oxide layer is (-201) preferred oriented ß-phase Ga2 O3 films. SIMS and XPS indicate that the residual N atoms as dopants remain in ß Ga2 O3 . XPS also demonstrates that the Fermi level is 0.2 eV lower than the central level of the band gap, indicating that the dominant carriers are holes and the ß Ga2 O3 is p-type conductive. Under a bias of -5 V, the photoresponsivity is 56 and 22 A W-1 for 255 and 360 nm, respectively. Correspondingly, the detectivities reach an ultrahigh value of 2.7 × 1015  cm Hz1/2 W-1 (255 nm) and 1.1 × 1015  cm Hz1/2 W-1 (360 nm). The high performance of this UV photodetector is attributed mainly to the continuous conduction band of the p-ß Ga2 O3 /n-GaN heterojunction without a potential energy barrier, which is more helpful for photogenerated electron transport from the space charge region to the n-type GaN layer.

Bariatric surgery reduces sleep apnea in obese patients with obstructive sleep apnea by increasing pharyngeal cross-sectional area during the early postoperative period.

OBJECTIVE: Bariatric surgery (BS) is considered one of the most effective treatments for obese individuals with Obstructive Sleep Apnea (OSA). However, otolaryngologists have raised concerns about the structural alterations caused by BS on the upper respiratory tract, especially, on the pharyngeal cavity. METHODS: In this study, we recruited 42 individuals who underwent BS at our hospital. They were divided into two groups based on apnea-hypopnea index (AHI): mild group (5 ≤ AHI < 15) and moderate-severe group (AHI ≥ 15). The participants were followed up for 12 months and several indicators, including body mass index (BMI), polysomnography (PSG), and acoustic pharyngometry (APh), were assessed repeatedly before surgery and at 3, 6, and 12 months (m) after surgery. RESULTS: Participants exhibited significant decreases in BMI (F = 128.1, P = 0.001) and total weight loss (F = 176.7, P < 0.001) after BS. The AHI value among obese patients with mild OSA decreased significantly within three months after surgery (0 day vs. 3 months, P < 0.01), and decreased significantly more than 12 months with moderate-to-severe patients (0 day vs. 3 months, 3 months vs. 6 months, 6 months vs. 12 months, P < 0.01). The therapeutic effect of OSA of the mild group was significantly better compared with that of the moderate-severe group at 6 months (mean rank = 28.13 vs. 14.21, P < 0.001) and 12 m (mean rank = 26.75 vs. 15.52, P = 0.001). The APh results revealed that the pharyngeal volume of the two groups increased significantly between 0 day and 6 months after surgery (P < 0.01). The oropharyngeal junction (OPJ) area and the glottal area were increased significantly between 0 day and 6 m after surgery (P < 0.01). CONCLUSION: BS can relieve apnea and OSA symptoms among obese patients with OSA, especially in the early postoperative period. Moreover, OSA severity was closely associated with OPJ and glottal areas, rather than pharyngeal cavity volume.

Combined application of pharyngeal volume and minimal cross-sectional area may be helpful in screening persons suspected of obstructive sleep apnea (OSA).

BACKGROUND: Obstructive sleep apnea (OSA) is a common disease that seriously affects human health and daily life. However, the gold standard for its diagnosis, polysomnography (PSG), is expensive resulting in inadequate diagnosis of this disease in primary clinics. Therefore, a simple and rapid method for initial screening for OSA is needed. Acoustic pharyngometry (APh) is an FDA-approved noninvasive method that is gradually being applied to screening for OSA. MATERIALS AND METHODS: In this study, we applied analysis with receiver operating characteristic (ROC) curves to explore how APh may play a greater role in the screening of subjects with suspected OSA. Patients admitted into the departments of otolaryngology at our hospital from March 2017 to May 2019 were recruited into the study. All subjects underwent PSG monitor and were separated into two groups according to the apnea-hypopnea index (AHI) from the PSG results: OSA group (AHI ≥ 5) and control group (AHI < 5). APh measurements and other indicators of the subjects, including age, height, and weight; Epworth Sleepiness Scale (ESS) score; and the pharynx examination, including the degree of tonsil enlargement and tongue hypertrophy, were also be recorded. RESULTS: The t-test results showed that almost all indicators except age and height have significant differences between the OSA group and control group. Subjects with OSA had greater weight, BMI, ESS, higher degree of tonsil enlargement, and tongue hypertrophy, while they had smaller minimal cross-sectional area (mCSA) and pharyngeal volume than the subjects in control group. The correlation analysis revealed that pharyngeal volume and mCSA were two helpful indicators to screen for OSA. Furthermore, we established the ROC curve and calculated the combining predictors (combining predictors = pharyngeal volume + mCSA * (- 2.347)/(- 0.225)). The area under the ROC curve (AUC) of combining predictors was 0.917 (95% CI 0.842-0.991, P < 0.001), which was higher than combinations of other two independent indicators. The cutoff point of combining predictors was found to be 59.84 (AUC = 0.917, sensitivity = 0.80, 1-specificity = 0.06, P < 0.001). CONCLUSIONS: These findings suggest that APh is a simple, rapid, and economical detection method which may be useful in screening for OSA, especially in communities and primary clinics where PSG cannot be performed.

Prevalence, toxin-typing and antimicrobial susceptibility of Clostridium perfringens in sheep with different feeding modes from Gansu and Qinghai provinces, China.

OBJECTIVE: The purpose of this study was to determine the prevalence and antimicrobial resistance of Clostridium perfringens from sheep (intensive husbandry) in Gansu and Tibetan sheep (extensive husbandry) in Qinghai, China. METHODS: 400 fecal samples (sheep, n = 320, Tibetan sheep, n = 80) were collected from Gansu and Qinghai for C. perfringens isolation. Toxin genes were detected by PCR, antimicrobial susceptibility testing was carried out by broth microdilution method, and whole genome was sequenced using Illumina HiSeq. RESULTS: 83 strains of C. perfringens (sheep, n = 47; Tibetan sheep, n = 36) were isolated from the samples. 44.5% (37/83) of the isolates were positive for cpb2, while 34.9% (29/83) of the isolates were positive for cna. 95.2% isolates were resistant to sulfonamides, followed by tetracycline (22.9%), ampicillin (14.5%), penicillin (10.8%), doxycycline (4.8%), and amoxicillin (1.2%). The isolates from same source shared similar allelic profile and closer genetic relationship. A total of 14 toxin genes and 11 antimicrobial resistance genes were detected among the sequenced isolates, and 10 sequenced C. perfringens isolates carried multiple (n ≥ 3) antimicrobial-resistance genes. Moreover, oxazolidinone-resistant gene optrA was detected in one isolate from Tibetan sheep, which co-harbored tetA(P), aac(6')-aph(2″), ant(6)-Ib, erm(Q), fexA, tet(44), erm(A) and erm(B). CONCLUSIONS: C. perfringens from sheep and Tibetan sheep shared different prevalence rates and antimicrobial-resistance, and the isolates from same source shared closer genetic relationship.

Research on an LEO Constellation Multi-Aircraft Collaborative Navigation Algorithm Based on a Dual-Way Asynchronous Precision Communication-Time Service Measurement System (DWAPC-TSM).

In order to solve the collaborative navigation problems in challenging environments such as insufficient visible satellites, obstacle reflections and multipath errors, and in order to improve the accuracy, usability, and stability of collaborative navigation and positioning, we propose a dual-way asynchronous precision communication-timing-measurement system (DWAPC-TSM) LEO constellation multi-aircraft cooperative navigation and positioning algorithm which gives the principle, algorithm structure, and error analysis of the DWAPC-TSM system. In addition, we also analyze the effect of vehicle separation range on satellite observability. The DWAPC-TSM system can achieve high-precision ranging and time synchronization accuracy. With the help of this system, by adding relative ranging and speed measurement observations in an unscented Kalman filter (UKF), the multi-aircraft coordinated navigation and positioning of aircraft is finally realized. The simulation results show that, even without the aid of an altimeter, the multi-aircraft cooperative navigation and positioning algorithm based on the DWAPC-TSM system can achieve good navigation and positioning results, and with the aid of the altimeter, the cooperative navigation and positioning accuracy can be effectively improved. For the formation flight configurations of horizontal collinear and vertical collinear, the algorithm is universal, and in the case of vertical collinear, the navigation performance of the formation members tends to be consistent. Under different relative measurement accuracy, the algorithm can maintain good robustness; compared with some existing classical algorithms, it can significantly improve the navigation and positioning accuracy. A reference scheme for exploring the feasibility of a new cooperative navigation and positioning mode for LEO communication satellites is presented.

Zeolite-Based Memristive Synapse with Ultralow Sub-10-fJ Energy Consumption for Neuromorphic Computation.

The development of neuromorphic computation faces the appreciable challenge of implementing hardware with energy consumption on the level of a femtojoule per synaptic event to be comparable with the energy consumption of human brain. Controllable ultrathin conductive filaments are needed to achieve such extremely low energy consumption in memristive synapses but their formation is difficult to control owing to their stochastic morphology and unexpected overgrowth. Herein, a zeolite-based memristive synapse is demonstrated for the first time, in which Ag exchange in the sub-nanometer pore closely resembles synaptic Ca2+ dynamics across biomembrane channel. Particularly, the confined ultrasmall pore and low Ag ion migration barrier give the zeolite-based memristive synapse ultralow energy consumption below 10 fJ per synaptic spike, on par with the biological counterpart. Experimental results reveal that the gradual memristive effect is attributed to the dimension modulation of Ag clusters. In addition to emulating inherent cognitive functions through electrical stimulations, the experience-dependent transition of short-term plasticity to long-term plasticity using a chemical modulation method is achieved by treating the initial Ag quantity as a learning experience. The proposed memristors can be used to develop highly efficient memristive neural networks and are considered as a candidate for application in neuromorphic computation.

Bioactive Peptides from Walnut Residue Protein.

Walnut residue is a kind of high-quality plant protein resource. The bioactive peptide prepared from walnut residue has excellent health care functions such as antioxidation and antihypertensive activity, but at present, walnut residue is often regarded as waste or low value feed, fertilizer and other materials. The uneconomical use of walnut residue has hindered the development of the walnut industry to some extent. Effective utilization of walnut residue protein to develop bioactive peptides and other products is of great significance to realize the comprehensive utilization of walnut residue, improve the added value of by-products, and change the current low utilization rate of walnut residue. In this paper, the preparation, purification and structure identification of walnut protein bioactive peptides are reviewed, and different functional walnut active peptides (WBPs) are introduced. The potential effects of these bioactivities on human health and their different uses in food, medicine and other industries are discussed. The purpose is to provide reference information for the effective utilization of walnut residue resources and the development of walnut industry.

Development of a TEM-cell-integrated CO2 incubator for cell-based transient electromagnetic field bioeffect study.

To facilitate the cell-based experiment for pulsed electromagnetic field biological effect study, a novel TEM-cell-integrated CO2 incubator was developed. The integrated experimental system could simultaneously meet the requirement of standard cell culture condition and the various Transient Electromagnetic Field (TEF) exposure, which made it possible to study the relationship between different electromagnetic pulse exposure and the cellular responses in a reliable way. During the research, a comparison experiment was carried out to evaluate the necessity of the integrated incubator system: firstly, two different types of cell lines, which are the human prostate cancer cell line (PC3) and the pancreatic ß cell line (MIN6) were chosen and exposed in the TEM-cell which located in the open area and the integrated system, respectively, with the same EFT radiation conditions; then, the cells' viability, the cellular ROS level and the mitochondrial membrane potential (MMP) were detected, respectively. The results showed that in the same parameter of the EFT radiation, the processes of the cells had a significant difference and even opposite in the incubator and open area, and all the results could be reproducible. The phenomenon indicated the stability of the TEM-cell-integrated CO2 incubator, and also demonstrated the necessity to strictly control the cell culture condition when carrying out the precise mechanism study of the TEF bioresponse at the cellular levels.

The clinical and prognostic significance of YWHAZ in non-small-cell lung cancer patients: Immunohistochemical analysis.

YWHAZ has been suggested to as an oncogene in various human malignancies, including non-small-cell lung cancer (NSCLC). Our study presents more evidence to confirm the clinical significance and biological function of YWHAZ in NSCLC. In our results, YWHAZ was upregulated in lung squamous cell carcinoma tissues and lung adenocarcinoma tissues through analyzing The Cancer Genome Atlas (TCGA) database, and confirmed high levels of YWHAZ messenger RNA and protein in lung squamous cell carcinoma tissues and lung adenocarcinoma tissues through quantitative real-time polymerase chain reaction and immunohistochemistry. Moreover, YWHAZ overexpression was correlated with advanced clinical stage, more lymph node metastasis and present distant metastasis in NSCLC patients. Survival analysis indicated that high level of YWHAZ protein expression was associated with short overall survival time in NSCLC patients, and YWHAZ expression was independent prognostic factors for overall survival in NSCLC patients. Moreover, Silencing of YWHAZ expression represses NSCLC cell migration and invasion. In conclusion, YWHAZ is a credible prognostic biomarker, and may be a therapeutic target in NSCLC.

Biodegradable Natural Pectin-Based Flexible Multilevel Resistive Switching Memory for Transient Electronics.

Transient electronics that can physically vanish in solution can offer opportunities to address the ecological challenges for dealing with the rapidly growing electronic waste. As one important component, it is desirable that memory devices combined with the transient feature can also be developed as secrecy information storage systems besides the above advantage. Resistive switching (RS) memory is one of the most promising technologies for next-generation memory. Herein, the biocompatible pectin extracted from natural orange peel is introduced to fabricate RS memory devices (Ag/pectin/indium tin oxides (ITO)), which exhibit excellent RS characteristics, such as forming free characteristic, low operating voltages (≈1.1 V), fast switching speed (<70 ns), long retention time (>104 s), and multilevel RS behaviors. The device performance is not degraded after 104 bending cycles, which will be beneficial for flexible memory applications. Additionally, instead of using acid solution, the Ag/pectin/ITO memory device can be dissolved rapidly in deionized water within 10 min thanks to the good solubility arising from ionization of its carboxylic groups, which shows promising application for green electronics. The present biocompatible memory devices based on natural pectin suggest promising material candidates toward enabling high-density secure information storage systems applications, flexible electronics, and green electronics.

Zero-biased deep ultraviolet photodetectors based on graphene/cleaved (100) Ga2O3 heterojunction.

In this paper, fast response, zero-biased, solar-blind UV photodetectors based on graphene/ß-Ga2O3 heterojunctions were fabricated by transferring a monolayer graphene onto fresh cleaved ß-Ga2O3 (100) single crystal substrate. At zero bias, the photo responsivity at 254 nm and the UV/visible rejection ratio (R235 nm/R400 nm) and the response time are obtained to be 10.3 mA/W and 2.28 × 102 and 2.24 µs, respectively, for the graphene/ß-Ga2O3 (100) detector. The fast response and the high sensitivity can be attributed to the high mobility and UV transparency of graphene top-electrode and the low defect density of the ß-Ga2O3 (100) cleaved surface. Such zero-biased detectors are very promising for next-generation solar-blind UV photodetection.

Newcastle disease virus selectively infects dividing cells and promotes viral proliferation.

Newcastle disease virus (NDV) can select cells to infect, but the mechanism of its cell selectivity has not been comprehensively investigated. Here, we use HeLa cells to establish that NDV can selectively infect cells at the single-cell level. We labeled proliferating cells with 5'-bromo-2-deoxyuridine (BrdU) and examined the colocalization of BrdU with NDV in cells to clarify the relationships between NDV infection and cell proliferation. Receptors at the plasma membrane mediate NDV entry into host cells. We labeled sialic acid receptor isoforms, compared their densities between different cell types and measured the sialic acid receptor densities in different cell phases. Our results suggest that NDV displays host tropism to HeLa cells compared to BHK cells and that the differences in the receptor isoform expression patterns between cell types contribute to the selection of HeLa by NDV. At the single-cell level, the dynamics of receptor expression changes during different cell phases contributing to the selection of cells in S/G2 phase for NDV infection. Furthermore, cell proliferation benefits viral replication, and enhanced virus replication leads to increased damage to cells. The elucidation of the mechanisms underlying host cell selection by NDV may help in the screening and characterizing of additional candidate oncolytic virus strains.

First report of bovine viral diarrhea virus and Mycobacterium avium subspecies paratuberculosis infection in Tibetan sheep (Ovis aries) in Tibetan Plateau, China.

Bovine viral diarrhea virus (BVDV) and Mycobacterium avium subspecies paratuberculosis (MAP) are important pathogens, which cause serious disease in animals. However, information about BVDV and MAP infection in Tibetan sheep in China is limited. Two thousand one hundred and eighty-seven blood samples were collected from Tibetan sheep between April 2013 and March 2014 from the Tibetan Plateau and tested for BVDV and MAP antibodies using commercial ELISA kits. The overall seroprevalence of BVDV and MAP in Tibetan sheep was 36.7 and 11.29%, respectively. Furthermore, risk factor analysis indicated that the age of sheep was statistically significant associated with BVDV infection and the region was considered as the risk factor of MAP infection in sheep (P < 0.05), gender and season were not considered as risk factors. This is the first report of seroprevalence and risk factors associated with BVDV and MAP infection in Tibetan Sheep in China, which will provide baseline information for controlling BVDV and MAP infection in ruminants in the Tibetan Plateau, western China.

Photocatalytic Reduction of Graphene Oxide-TiO2 Nanocomposites for Improving Resistive-Switching Memory Behaviors.

Graphene oxide (GO)-based resistive-switching (RS) memories offer the promise of low-temperature solution-processability and high mechanical flexibility, making them ideally suited for future flexible electronic devices. The RS of GO can be recognized as electric-field-induced connection/disconnection of nanoscale reduced graphene oxide (RGO) conducting filaments (CFs). Instead of operating an electrical FORMING process, which generally results in high randomness of RGO CFs due to current overshoot, a TiO2 -assisted photocatalytic reduction method is used to generate RGO-domains locally through controlling the UV irradiation time and TiO2 concentration. The elimination of the FORMING process successfully suppresses the RGO overgrowth and improved RS memory characteristics are achieved in graphene oxide-TiO2 (Go-TiO2 ) nanocomposites, including reduced SET voltage, improved switching variability, and increased switching speed. Furthermore, the room-temperature process of this method is compatible with flexible plastic substrates and the memory cells exhibit excellent flexibility. Experimental results evidence that the combined advantages of reducing the oxygen-migration barrier and enhancing the local-electric-field with RGO-manipulation are responsible for the improved RS behaviors. These results offer valuable insight into the role of RGO-domains in GO memory devices, and also, this mild photoreduction method can be extended to the development of carbon-based flexible electronics.

Newcastle disease virus V protein inhibits apoptosis in DF-1 cells by downregulating TXNL1.

Many viral proteins are related to suppressing apoptosis in target cells and are hence beneficial to viral replication. The V protein of Newcastle disease virus (NDV) is one such protein that plays an important role in inhibiting apoptosis in a species-specific manner. However, to date, there have been no reports clarifying the antiapoptotic mechanisms of the V protein. The present study was undertaken to determine the apoptotic potential of the V protein in a chicken embryo fibroblast cell line (DF-1 cell) and to elucidate its molecular mechanisms of action. Here, a yeast two-hybrid system was used to screen the host proteins that interact with the V protein and identified thioredoxin-like protein 1 (TXNL1) as a potential binding partner. Immuno-colocalization of V protein and TXNL1 protein in DF-1 cells further verified the interaction of the two proteins. Through the overexpression of TXNL1 protein and knockdown of TXNL1 protein in DF-1 cells, the effects of NDV replication and cell apoptosis were examined. Cell apoptosis was detected by flow cytometry. The mRNA and protein expression levels of Bax, Bcl-2 and Caspase-3 were detected by quantitative real-time PCR (Q-PCR) and Western blotting. NDV expression was detected by Q-PCR and plaque assay. The results revealed that the TXNL1 protein induced apoptosis and inhibited NDV replication in DF-1 cells. Furthermore, the Western blot and Q-PCR results suggested that TXNL1 induced cell apoptosis through a pathway involving Bcl-2\Bax and Caspase-3. Finally, this work provides insight into the mechanism by which the V protein inhibits apoptosis.

Accurate identification of layer number for few-layer WS2 and WSe2 via spectroscopic study.

Transition metal dichalcogenides (TMDs) with a typical layered structure are highly sensitive to their layer number in optical and electronic properties. Seeking a simple and effective method for layer number identification is very important to low-dimensional TMD samples. Herein, a rapid and accurate layer number identification of few-layer WS2 and WSe2 is proposed via locking their photoluminescence (PL) peak-positions. As the layer number of WS2/WSe2 increases, it is found that indirect transition emission is more thickness-sensitive than direct transition emission, and the PL peak-position differences between the indirect and direct transitions can be regarded as fingerprints to identify their layer number. Theoretical calculation confirms that the notable thickness-sensitivity of indirect transition derives from the variations of electron density of states of W atom d-orbitals and chalcogen atom p-orbitals. Besides, the PL peak-position differences between the indirect and direct transitions are almost independent of different insulating substrates. This work not only proposes a new method for layer number identification via PL studies, but also provides a valuable insight into the thickness-dependent optical and electronic properties of W-based TMDs.

Toxoplasma gondii Infection in Farmed Wild Boars (Sus scrofa) in Three Cities of Northeast China.

The apicomplexan protozoan parasite Toxoplasma gondii is a widely distributed etiological agent of foodborne illness. This parasite can cause production losses in livestock and serious disease in humans through consumption of contaminated meat. Pig meat is the most likely source of human infection, and wild boars may play a role in the transmission of T. gondii by serving as a reservoir host. This study aimed to investigate the seroprevalence of antibodies to T. gondii among farmed wild boars in China. In an 11-month survey, a total of 882 serum samples were obtained from farmed wild boars from three cities (Jilin City, Siping City, and Baishan City) in Jilin province, Northeast China and were tested for antibodies specific for T. gondii. Using modified agglutination test and a cutoff titer of 1:25, the prevalence of T. gondii infection in the examined samples was 10.0% (88 of 882). The highest seroprevalence was observed in animals from Jilin city (15.3%, 43/281) and followed by Siping (11.4%, 30/263) and Baishan (4.4%, 15/338). Logistic regression analysis revealed a significant correlation between the investigated geographic region and T. gondii infection. In addition, prevalence was higher in females compared to males, and the highest prevalence was detected in piglets. These findings indicate that farmed wild boars may become a source of foodborne toxoplasmosis, posing a food safety threat to the public health in the investigated areas. Implementation of effective measures to control T. gondii infection in farmed wild boars in China may be warranted.

Seroprevalence and Risk Factors of Fascioliasis in Yaks, Bos grunniens, from Three Counties of Gansu Province, China.

The aim of this study was to determine the seroprevalence and risk factors of fascioliasis in yaks, Bos grunniens, from 3 counties of Gansu Province in China. A total of 1,584 serum samples, including 974 samples from white yaks from Tianzhu, 464 from black yaks from Maqu, and 146 from black yaks from Luqu County, were collected and analyzed using ELISA to detect IgG antibodies against Fasciola hepatica. The overall F. hepatica seroprevalence was 28.7% (454/1,584), with 29.2% in white yaks (284/974) and 27.9% in black yaks (170/610). The seroprevalence of F. hepatica in yaks from Tianzhu, Luqu, and Maqu was 29.2%, 22.6%, and 29.5%, respectively. Female yaks (30.9%) had higher F. hepatica seroprevalence than male yaks (23.4%). Also, F. hepatica seroprevalence varied by different age group from 24.1% to 33.8%. Further, the seroprevalence ranged from 21.8% to 39.1% over different seasons. Interestingly, the season and age of yaks were associated with F. hepatica infection in yaks in the investigated areas. These findings provided a basis for further studies on this disease in yaks from 3 counties of Gansu Province in northwestern China, which may ultimately support the development of effective control strategies of fascioliasis in these areas.

Prevalence and risk factors of Cryptosporidium infection in farmed pigs in Zhejiang, Guangdong, and Yunnan provinces, China.

Cryptosporidiosis is caused by species of Cryptosporidium protozoa that can infect a wide range of host animals worldwide. However, data regarding Cryptosporidium infection in farmed pigs in subtropical areas in China is limited. Therefore, a total of 396 fecal samples were obtained from farmed pigs from Zhejiang (n = 124), Guangdong (n = 72), and Yunnan (n = 200) provinces, China, and were tested by PCR amplification of the small subunit (SSU) rRNA gene. The overall prevalence of Cryptosporidium in pigs was 17.68% (70/396), with 20.11% (36/179) in male pigs and 15.67% (34/217) in female pigs. Additionally, Cryptosporidium prevalence was 8.33% (6/72) in Guangdong province, 14.52% (18/124) in Zhejiang province, and 23.00% (46/200) in Yunnan province. A DNA sequence analysis of the SSU rRNA gene revealed that all of the isolates represented C. scrofarum. This is the first report of C. scrofarum infection in pigs in Guangdong and Yunnan provinces in subtropical areas of China. The results of the present study provide foundation data for control and prevention of Cryptosporidium infection in pigs in the study areas in China.