Results of active surveillance of foodborne diseases in Pudong New Area of Shanghai, 2015-2018

Objective To understand the epidemic trend and characteristics of foodborne diseases caused by specific pathogens in Pudong New Area of Shanghai, so as to provide scientific evidence for disease prevention and control. Methods From 2015 to 2018, the infectious cases with diarrhea as the main complaint were collected from the sentinel hospital of foodborne disease active monitoring in Pudong New Area of Shanghai. Stool or anal swab samples were collected and tested for Vibrio parahaemolyticus, Salmonella, Shigella, diarrheogenic Escherichia coli, Campylobacter jejuni and Norovirus. At the same time, the profiles were collected and analyzed. Results In 2015-2018, 2 871 stool or anal swab samples of diarrhea cases were monitored and collected. The positive rate of pathogens was 23.55% (676/2 871), including Norovirus 20.04% (97/484), diarrheogenic Escherichia coli 11.84% (340/2 871), Campylobacter jejuni 7.21% (68/943), Vibrio parahaemolyticus 4.01% (115/2 871), Salmonella 3.27% (94/2 871) and Shigella 0.28% (8/2 871). The positive rate was higher in the third quarter, showing a significant peak in summer and autumn. Suspicious food was mainly mixed food (41.12%, 278/676), followed by aquatic animals and their products (22.19%, 150/676) and meat and meat products (10.95%, 74/676). Conclusion Norovirus and diarrheogenic Escherichia coli were the main pathogens of diarrhea cases in Pudong New Area of Shanghai. We should further improve the foodborne disease active monitoring system, carry out detailed epidemiological case investigation for specific pathogen positive cases, and provide technical support for effective prevention and control

Nano α-FeOOH Modified Carbon Paste Electrode for Arsenic Determination in Natural Waters

A novel method for determination of inorganic arsenic in natural water, based on nano ferric hydroxides (FeOOH) preconcentration and electrochemistry detection has been developed. As the nano α-FeOOH could successfully act as the adsorbent and electrode matrix modifier, the method presents great potential in practical routine analysis of inorganic arsenic. With optimization of the experimental conditions, nano α-FeOOH modified carbon paste electrode (α-FeOOH@CPE) was obtained by mixing 0.03 g of nano α-FeOOH and 0.02 g graphite powder in n-eicosane as an adhesive and then embedding them in a Teflon tube. Cyclic voltammetry, chronoamperometry and high resolution transmission electron microscopy were used to check and confirm the presence of nano α-FeOOH on the carbon paste electrodes. According to the results, α-FeOOH@CPE showed a considerably higher response to As(III) in comparison with the bare CPE, indicating the α-FeOOH has well selective enrichment for As(III). The developed modified electrode showed a linear range of 1.0 × 10-8 ~ 2.0 × 10-5 mol·L-1 and detection limit of 5.0 nmol·L-1 (S/N = 3). The newly prepared carbon paste electrode was successfully applied for As(III) determination in Yangzonghai Lake water with RSD of less than 3.6 % (n = 3) and recovery in the range of 100.7 ~ 115.0 %. DOI: http://dx.doi.org/10.5755/j01.ms.24.4.18499</p

Slc35a1 deficiency causes thrombocytopenia due to impaired megakaryocytopoiesis and excessive platelet clearance in the liver

Sialic acid is a common terminal residue of glycans on proteins and acidic sphingolipids such as gangliosides with important biological functions. The sialylation process is controlled by more than 20 different sialyltransferases, many of which exhibit overlapping functions. Thus, it is difficult to determine the overall biological function of sialylation by targeted deletion of individual sialyltransferase. To address this question, we established a mouse line with the Slc35a1 gene flanked by loxP sites. Slc35a1 encodes the CMP-sialic acid transporter that transports CMP-sialic acid from cytoplasm into the Golgi apparatus for sialylation. Here we report our study regarding the role of sialylation on megakaryocytes and platelets using a mouse line with significantly reduced sialylation in megakaryocytes and platelets (Plt Slc35a1-/-). The major phenotype of Plt Slc35a1-/- mice was thrombocytopenia. The number of bone marrow megakaryocytes in Plt Slc35a1-/- mice was reduced, and megakaryocyte maturation was also impaired. In addition, an increased number of desialylated platelets was cleared by Kupffer cells in the liver of Plt Slc35a1-/- mice. This study provides new insights into the role of sialylation in platelet homeostasis and the mechanisms of thrombocytopenia in diseases associated with platelet desialylation, such as immune thrombocytopenic purpura and a rare congenital disorder of glycosylation (CDG), SLC35A1-CDG, which is caused by SLC35A1 mutations.

Assessing the economic performance of an environmental sustainable supply chain in reducing environmental externalities

This study investigates the mechanism that motivates supply chain firms to reduce environmental ex- ternalities while balancing the economic feasibility of the supply chain system under environmentally constrained circumstances in a competitive market. Taking government policy incentives into account, a quantitative model of an integrated supply chain that incorporates sustainable constraints is formu- lated to optimize supply chain firms’ operational strategies of producing environmental friendly products (EFPs). This study contributes to the literature with a better understanding the interplay and interrelation of multiple sustainable constraints and their impact on supply chain firms’ collaborative decisions. Our findings suggest that the decisions of operating EFPs are subject to sustainable constraints and that the government policy incentives play a dominant role overseeing supply chain firms’ environmental behav- iors toward sustainability

Stock price crashes in emerging markets

This paper studies large price declines of individual stocks in 22 emerging markets. Using analyst reports as a proxy for information arrivals, we find that majority of crashes in emerging markets are not accompanied by information events, and these crashes are followed by price reversals. Further analyses show that crashes in countries with a better information environment or a lower level of openness are less likely to reverse in the short run, suggesting that factors such as information transparency and market integration may shape the large swings in emerging market stock prices

Function of a Deep-Buried Isolated Trench and Its Effect on Cracking Failure Characteristics of a Slope under Artificial Rainfall

When tests are conducted on the field slope under artificial rainfall, because artificial rainfall is often limited to implementation in the mode of local rainfall, there is a boundary constraint effect between the rainfall area and the non-rainfall area, which is manifested in the lateral infiltration of rainwater and the slope deformation retardation of non-rainfall area to the rainfall area. Firstly, a deep-buried isolated trench was proposed to solve these boundary constraints. Then, field cracking tests and the corresponding numerical simulation were conducted under rainfall. In the end, the response of water content and the cracking failure characteristics of the slope were analyzed during rainfall, and the effect of a deep-buried isolated trench on the cracking characteristics of the slope was evaluated. The results indicate that the proposed deep-buried isolated trench measure can effectively eliminate the deformation retardation resulting from the adjacent non-rainfall area so a through-crack parallel to the slope shoulder that extended on both sides of the boundary of the rainfall slope was observed at the slope crest and a cracking failure in the shape of the overall downward cutting was realized. As the crack occurred, the rainwater infiltration further aggravated expansion of depthwise cracks, and a local sliding zone was formed in the upper part of the slope. The deep-buried isolated trench solves the boundary constraints, such as lateral infiltration of rainwater and deformation retardation, and can provide an effective technical measure for the field slope test under artificial rainfall

Numerical Simulation of Temperature Field and Melt Pool Characteristics of CP-Ti Manufactured by Laser Powder Bed Fusion

A coupled heat source model that combined a Gauss surface heat source with a Gauss cylindrical volumetric heat source was introduced to simulate temperature field distribution and melt pool characteristics using a finite element simulation (FEM) method for the deep and narrow melt pools formed in laser powder bed fusion (L-PBF) aiming at commercial pure titanium (CP-Ti). For comparison, the same simulations using the Gauss surface heat source model and the double ellipsoid heat source model were also performed. The simulated melt pool geometries using the coupled heat source model match well with the measurements, with an average error of 1% for the melt pool depth and 7% for the width. Based on the single-track experimental results, it was found by comparing the simulated results from the three heat source models that the coupled heat source model had better accuracy than the other two. Then, the temperature field and the melt pool geometries of CP-Ti fabricated at different laser power levels from 300 W to 500 W and scanning speeds from 600 mm/s to 4000 mm/s were simulated. According to the simulated maximum temperature and geometries of the melt pool, a suitable process parameters map for CP-Ti was obtained. The reported experimental results agree well with the simulated map. The coupled heat source model is more accurate and applicable for the deep and narrow melt pools formed during L-PBF

A New Scale to Assess the Severity and Prognosis of Pulmonary Alveolar Proteinosis

Background. Pulmonary Alveolar Proteinosis (PAP) is a syndrome characterized by pulmonary surfactant accumulation. Small proportion of PAP patients experienced spontaneous remission. Objective. The aim of this study was to assess the severity and prognosis of PAP using various indexes. Methods. Characteristics, PaO2, lung function parameters, and HRCT score of 101 patients with PAP were retrospectively analyzed. Many indexes were explored and integrated into a scale. Results. PaO2 was lower among smokers than among never-smokers. PaO2 differed between each pair of patient groups stratified according to HRCT score or DLCO, % predicted, which differed between any two groups stratified according to PaO2. The PAP patients who died presented with more symptoms, a higher HRCT score, and lower DLCO, % predicted, than survivors. Smoking status, symptoms, PaO2, HRCT score, and DLCO, % predicted, were integrated into a scale (severity and prognosis score of PAP (SPSP)). SPSP correlated positively with PaO2, FVC, % predicted, FEV1, % predicted, and DLCO, % predicted, and negatively with HRCT score. The patients who died displayed a higher SPSP than survivors. Conclusion. Smoking status, symptoms, PaO2, HRCT score, and DLCO, % predicted, were integrated into a scale (SPSP) that can be used to assess the severity and prognosis of PAP to some degree

Annealing Effects on GaAs/Ge Solar Cell after 150 keV Proton Irradiation

Radiation-induced defects are responsible for solar cell degradation. The effects of radiation and annealing on the defects of a GaAs/Ge solar cell are modeled and analyzed in this paper. The electrical performance and spectral response of solar cells irradiated with 150 keV proton are examined. Then, thermal annealing was carried out at 120°C. We found that the proportion of defect recovery after annealing decreases with increasing irradiation fluence. The minority carrier lifetime increases with decreasing defect concentration, which means that the electrical performance of the solar cell is improved. We calculated the defect concentration and minority carrier lifetime with numerical simulation and modeled an improved annealing kinetic equation with experimental results