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Due to the lack of monitoring systems and water purification facilities, residents in western China may face the risk of drinking water pollution. Therefore, 673 samples were collected from Lhasa's agricultural and pastoral areas to reveal the status quo of drinking water. We used inductively coupled plasma-mass spectrometry to determine trace elements concentrations for water quality appraisal, source apportionment, and health risk assessment. The results indicate that concentrations of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Ba, and Pb are below the guidelines, while As concentrations in a few samples exceed the standard. All samples were classified into "excellent water" for drinking purpose based on Entropy-weighted water quality index. Thereafter by principal component analysis, three potential sources of trace elements were extracted, including natural, anthropogenic, and mining activities. It is worth noting that geotherm and mining exploitation does not threaten drinking water safety. Finally, health risks were assessed using Monte Carlo technique. We found that the 95th percentiles of hazard index are 1.80, 0.80, and 0.79 for children, teenagers, and adults, indicating a non-carcinogenic risk for children, but no risks for the latter two age groups. In contrast, the probabilities of unacceptable cautionary risk are 7.15, 2.95 and 0.69% through exposure to Cr, Ni, As, and Cd for adults, children, and teenagers. Sensitivity analyses reveal As concentration and ingestion rate are most influential factors to health risk. Hence, local governments should pay more attention to monitoring and removal of As in the drinking water.

It is still challenging to make accurate diagnosis of biliary atresia (BA) with sonographic gallbladder images particularly in rural area without relevant expertise. To help diagnose BA based on sonographic gallbladder images, an ensembled deep learning model is developed. The model yields a patient-level sensitivity 93.1% and specificity 93.9% [with areas under the receiver operating characteristic curve of 0.956 (95% confidence interval: 0.928-0.977)] on the multi-center external validation dataset, superior to that of human experts. With the help of the model, the performances of human experts with various levels are improved. Moreover, the diagnosis based on smartphone photos of sonographic gallbladder images through a smartphone app and based on video sequences by the model still yields expert-level performances. The ensembled deep learning model in this study provides a solution to help radiologists improve the diagnosis of BA in various clinical application scenarios, particularly in rural and undeveloped regions with limited expertise., It is still challenging to make accurate diagnosis of biliary atresia (BA) with sonographic gallbladder images particularly in rural areas without relevant expertise. Here, the authors develop a diagnostic deep learning model which favourable performance in comparison with human experts in multi-center external validation.

Upper gastrointestinal (GI) abnormalities are one of the most common disease in clinical practice, and among them, gastric cancer is one of the most common causes of cancer-related death in China. However, conventional trans-abdominal ultrasound is difficult to evaluate GI diseases due to gas filled in the GI tract. With the development of oral contrast agents in China, ultrasonography with oral contrast agent has been used to visualize upper GI tract (i.e., stomach and duodenum) as well as its surrounding structures. The primary purposes of this consensus and guideline written by Chinese experts is to provide a coherent and clinical perspectives and practical protocol for using oral contrast in upper GI ultrasound, including four components: (1) indications and contraindications of gastric contrast ultrasound; (2) patients and instruments preparation; (3) scanning technique and imaging acquisition; (4) diagnosis of upper GI abnormalities.

It is still difficult to make accurate diagnosis of biliary atresia (BA) by sonographic gallbladder images particularly in rural area lacking relevant expertise. To provide an artificial intelligence solution to help diagnose BA based on sonographic gallbladder images, an ensembled deep learning model was developed based on a small set of sonographic images. The model yielded a patient-level sensitivity 93.1% and specificity 93.9% (with AUROC 0.956) on the multi-center external validation dataset, superior to that of human experts. With the help of the model, the performance of human experts with various levels would be improved further. Moreover, the diagnosis based on smartphone photos of sonographic gallbladder images through a smartphone app and based on video sequences by the model still yielded expert-level performance. Our study provides a deep learning solution to help radiologists improve BA diagnosis in various clinical application scenarios, particularly in rural and undeveloped regions with limited expertise.

Au nanoparticles on ZnO nanorods is a sustainable catalyst for oxygen-promoted, base-free, complete formaldehyde reforming into H2 and CO2 at low temperatures. The strong metal-support interaction (SMSI) between Au and ZnO is suggested to be responsible for this catalytic feature partially due to the presence of surface cationic Au+ species formed during high temperature treatment in air. in-situ EPR and resonance Raman analysis show that a two-electron reduction pathway is involved to produce hydrogen peroxide as the active species and C H bond cleavage is the rate-determining step.

Carboxymethyl cellulose (CMC) has been broadly used in various fields ranging from pharmacy to lithium batteries because of its excellent properties such as the environmental friendliness, the good solubility, its low cost and biocompatibility. Herein, we present a direct electrodeposition method for carboxymethyl cellulose based on the coordination deposition. Using this method we can conveniently build smooth and homogeneous CMC films on the surface of copper and silver electrodes (or substrates). On the other hand, the deposited CMC film has sufficient strength to be completely detached from the electrodes (or substrates), which enables a novel and controllable method to prepare CMC films that can be used as independent film materials. In particular, the deposited CMC film shows favorable antibacterial activities, which are promising for applications in bioactive antibacterial coatings on metal substrates. More interestingly, the CMC electrodeposition provides the possibility to directly build sensors and detectors for electrochemical detection. Therefore, the CMC electrodeposition developed in this study can be potentially applied in surface coatings, functional films, and sensors.

Purpose. To investigate the diagnostic performance of shear wave elastography (SWE) for measuring liver stiffness to identify and differentiate biliary atresia (BA) from cholestatic hepatitis in infants younger than 90 days. Methods. A total of 138 infants younger than 90 days with cholestatic hepatitis were examined by SWE. The infants were subclassified into BA and nonbiliary atresia (non-BA) groups. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of hepatic Young’s modulus measurements, the ultrasonic findings in the differential diagnosis of suspected BA, and the cut-off value to diagnose BA. Results. In all infants with cholestatic hepatitis, the cut-off value of hepatic Young’s modulus to differentiate the BA group from the non-BA group was 12.35 kPa and the area under the ROC curve (AUC) was 0.937, with a sensitivity of 84.3% and a specificity of 89.7%; nevertheless the AUC of the abnormal gallbladder (AbGB) was 0.940, with a sensitivity of 96.1% and a specificity of 92.0%. In the parallel test, triangular cord (TC) sign combined with AbGB had the best diagnostic performance and the AUC was 0.960, with a sensitivity of 100% and a specificity of 92.0%. In the serial test, SWE combined with AbGB achieved the best diagnostic performance; the AUC was 0.902, the sensitivity and specificity were 80.4% and 100%, respectively. Conclusions. SWE could not only help differentiate BA from cholestatic hepatic diseases but also increase the diagnostic specificity when combined with grey-scale ultrasound in the serial test.

In our previous study, Lactobacillus paracasei FX-6 was isolated from kefir, and the antimicrobial substance produced by FX-6 had broad spectrum antimicrobial activity, which had a good effect of preservation on chicken breast and could significantly inhibit the dominant spoiled bacteria Pseudomonas. In this study, we isolated and identified the dominant bacteria Pseudomonas, and we also researched the antibacterial effect and mechanism of antibacterial substance against Pseudomonas. The dominant bacteria Pseudomonas was isolated from spoiled chicken breast meat and identified as Pseudomonas putida. The result showed that the minimum inhibitory concentration (MIC) of antibacterial substance against Pseudomonas putida was 12.5 mg/mL. The Propidium iodide (PI) infiltration experiments and leakage of potassium ions indicated the antimicrobial substance could increase the permeability of the bacterial cell membrane. Scanning electron microscope (SEM) revealed that the antimicrobial substance damaged the morphology of Pseudomonas putida cell. Result of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) suggested that the synthesis of protein of Pseudomonas putida could be affected by the antibacterial substance. The result of agarose gel retardation indicated that the genomic DNA could be combined with the antimicrobial substance.

In our previous study, Lactobacillus paracasei FX-6 was isolated from kefir, and a novel bacteriocin with broad spectrum antimicrobial activity was identified from its fermentation. The aim of this study was to investigate the effects of this antimicrobial substance on chicken breast during refrigerated storage, specifically with regards to pH, total volatile base nitrogen (TVB-N), total viable counts (TVC) and sensory evaluation. Our results showed that the shelf life of chicken breast was prolonged for 4 more days after treatment with 100 mg/mL of antimicrobial substance. Significant differences in volatile organic compound (VOC) were found between the control and test groups. Results from high-throughput sequencing showed that Citrobacter and Acinetobacter were the dominant genera in fresh chicken breast. As time in storage increased, Pseudomonas (89.7%), Hafnia-Obesumbacterium (3.1%) and Serratia (2.6%) became the predominant genera in the control group when the meat was spoiled (day 8). However, these predominant bacteria were effectively inhibited by the antimicrobial substance.

The succession of bacterial microbiota in tilapia fillets during cold storage at 4 °C was investigated employing PCR-DGGE method. Results showed that Pseudomonas was the most dominant genus during entire storage period. Shewanella and Psychrobacter were also always present, but became dominant only after 3 days of storage. Acinetobacter, Brevibacterium, Flavobacterium, Dietzia and Janthinobacterium were always the minor genera, among which Acinetobacter and Brevibacterium disappeared 6 days later, and Dietzia and Janthinobacterium only appeared at the end of storage. Further, the potential spoiler(s) of tilapia fillets at 4 °C were investigated in situ. The spoilage ability of a specific group of bacteria was evaluated as follows: Certain preservatives were selectively added to fillets to inhibit a specific group of bacteria, and then the changes in spoilage degree of fillets were determined. In this way the spoilage ability of the inhibited bacteria was evaluated. Our experiments showed that protamine strongly inhibited Pseudomonas but rarely inhibited Psychrobacter, Acinetobacter and Brevibacterium, but garlic juice, on the contrary, strongly inhibited the latter three but rarely inhibited the former. The mixed preservative, which consisted of protamine and garlic juice, didn't play better than protamine alone in preventing the spoilage of fillets. This indicated that Psychrobacter, Acinetobacter and Brevibacterium contribute little to the spoilage of tilapia fillets.

To evaluate intraventricular systolic dyssynchrony in rats with post-infarction heart failure by quantitative tissue velocity imaging combining synchronous electrocardiograph.A total of 60 male SD rats were randomly assigned to 3 groups: a 4 week post-operative group and an 8 week post-operation group (each n=25, with anterior descending branch of the left coronary artery ligated), and a sham operation group (n=10, with thoracotomy and open pericardium, but no ligation of the artery). The time to peak systolic velocity of regional myocardial in the rats was measured and the index of the left intraventricular dyssynchrony was calculated.All indexes of the heart function became lower as the heart failure worsened except the left ventricle index in the post-operative groups. All indexes of the dyssynchrony got longer in the post-operative groups (P0.05), while the changes in the sham operation group were not significantly different (P0.05).Quantitative tissue velocity imaging combining synchronous electrocardiograph can analyse the intraventricular systolic dyssynchrony accurately.

To quantitatively detect variation in regional myocardial systolic function in heart failure rat model induced by myocardial infarction by strain and strain rate imaging.Seventy 2-month-old adult male SD rats were randomly assigned to 4 groups: a 4-week and a 8-week group after the operation (each n = 25) had thoracotomy, the pericardium opened and the anterior descending branch of left coronary artery ligated; a sham operation group (n = 10) had thoracotomy and the arcula cordis opened, but did not ligate the artery; a control group (n = 10) had no treatment. The changes of general state of health of the rats were observed and recorded every day. To assess the change of heart function, echocardiography was used at the end of the 4th week and 8th week after the surgery. To evaluate the change of heart function in heart failure rats, we quantitatively analyzed the regional myocardial systolic function in all rats by strain and strain rate imaging and myocardium to detect the level of MMP-9 at the end of the 4th week and 8th week. The repeatability and discrepancies of the results were all analyzed.Obviously objective signs of heart failure manifested themselves in the survived mice 10 to 14 days after the surgery. Compared with the control group and the sham operation group, the fraction shortening (FS) and ejection fraction (EF) of the 4-week group after the operation were lower (P0.05), the left ventricle index (LV index) of the 8-week group after the operation was higher, left ventricle posterior wall index (LVPW index), interventricular septum index (IVS index), FS, and EF of the 8-week group after the operation were lower (P0.05), EF and FS of the 8-week group after the operation were lower than those of the 4-week group. Except the mid-inferior wall and base-inferior wall, the systolic peak strain, systolic peak strain rate, the strain of end-systole in all segments of the operation group were lower than those of the other 2 groups (P0.05). The post-systolic strain index of the operation group was higher than that of the other 2 groups (P0.05).Strain and strain rate imaging of echocardiography can quantitatively evaluate the changing of regional myocardial systolic function in the heart failure rat model induced by myocardial infarction, with good repeatability.