Search

In this paper, we investigate the space-time pointwise behaviors of global solutions to the pressureless Euler-Navier-Stokes system in three dimensions, which characterizes the motion of a twophase fluid. First, we construct the Green's function for the linearized system, which consists of the Huygens wave, the diffusion wave, the Riesz wave, and the singular part containing the stationary delta wave arising from the pressureless structure. Then, under the assumptions on the initial data with appropriate spatial decay rates, we obtain the space-time pointwise estimates of global solutions to the Cauchy problem for the linearized system. [ABSTRACT FROM AUTHOR]

The abnormal concentration of adenosine 5-triphosphate (ATP) in cancer cells is closely related to the process of tumorigenesis and development. Therefore, rapid and accurate detection of ATP level in and out of cells is of great significance. Graphene oxide (GO) is widely used owing to its advantages of low toxicity, large specific surface area, easy functionalization, efficient and stable loading of DNA nanoprobes into cells. However, ssDNA bound to GO by physical adsorption is easily displaced by biomolecules in complex biological environment, leading to false positive signals. Based on this, a novel GO-DNA nanoprobe is proposed and applied to the detection of ATP and targeted delivery of the anticancer drug doxorubicin hydrochloride (DOX). Double stranded DNA (dsDNA) is formed by hybridization of aptamer of ATP with complementary strand, and then DOX is loaded by G-C base pair to form dsDNA-DOX. dsDNA-DOX is adsorbed on GO surface through polyA sequence extended by complementary strand to construct GO-dsDNADOX nanoprobes, which could greatly reduce false positive signal caused by the physical adsorption of biomolecules in complex environment. The specific binding of ATP to aptamer can lead to the release of DOX, and quantitative analysis of ATP is achieved according to its fluorescence “off-on”. DOX fluorescence intensity shows a good linear relationship with the ATP content within the range of 0. 08~8. 0 mmol/L, and the linear equation is IF=3. 0897c+129. 08. The detection limit (3σ/k) is 0. 059 mmol/L, and the method has good selectivity and anti-interference ability. Cytotoxicity and fluorescence imaging results show that the DOXloaded nanoprobes have significant drug release in MCF-7 cells and significantly induce apoptosis. This study establishes a label-free, simple and rapid method for ATP content detection and realizes targeted drug delivery by the high content of ATP in cancer cells, which reduces the toxic and side effects on normal cells and provides a new idea for cancer treatment. [ABSTRACT FROM AUTHOR]

Objective To explore the current situation of disease prevention and control ability and training needs of grassroots public health personnel in Luzhou, to provide a reference for improving the disease prevention and control ability of grassroots public health personnel in Luzhou, Methods A questionnaire survey was conducted on 1 075 people engaged in disease control work in township health centers, village clinics, and community health service centers (stations) in Luzhou City to analyze their disease prevention and control ability and influencing factors. Results The average self 一 evaluation score of basic disease prevention and control ability skills of primary public health personnel in Luzhou City was 57. 93 ± 27. 30 points, with a score rate of 46. 72%. Among them, r prevention and control of chronic non - communicable diseasesir had the highest score rate of 56. 94%, and, r prevention and control of endemic and parasitic diseases" had the lowest score rate of 37. 75%. Among the survey respondents, 92.37% had participated in basic knowledge or skills training in disease control, and the proportion of those who chose, r on - site guidance1 r as the desired form of training was the highest, at 80. 74%. The results of multiple linear regression analysis showed that the factors affecting the ability of primary public health personnel in disease prevention and control were mainly female(£ 二-3. 425, P = 0. 001), outside the establishment(£ 二 3. 322, P = 0. 001), not having participated in training in basic knowledge or skills of disease control(£ 二 -6. 119, P < 0.001), professional background (non 一 medical t - -2. 083, P = 0. 038) and professional background (non 一 medical £ 二 一 0. 083, P = 0. 038). Conclusion The disease prevention and control ability of grassroots public health personnel in Luzhou City is relatively weak, with gender, professional background, establishment, and whether they have participated in training being the main influencing factors, requiring targeted training in relevant knowledge and skills. [ABSTRACT FROM AUTHOR]

Using our team's recent research achievement “the cervical ultrasound scanning route map” as a teaching tool, to evaluate its impact on the learning effectiveness and confidence of beginners in the process of learning cervical spinal ultrasonography. Methods This study is a before and after self-control study. After recruitment of 40 cervical ultrasound beginners, they had completed questionnaire 1. The questionnaire was designed with three self-assessment questions on theoretical knowledge of cervical spinal ultrasound, three self-assessment questions on practical skills of cervical spinal ultrasound and one question on willingness to use cervical spinal ultrasound in the future. After traditional teaching without involving the route map, beginners completed questionnaire 2 with the same content. After a 20 min break, teacher introduced and explained the route map to the beginners, then the beginners completed questionnaire 3. Questions related to satisfaction with this learning experience had been added to questionnaire 3. The answers to all questions were scored on a scale of 1-10. In this study, the main outcome was the comprehensive learning score, calculated as(sum score of theoretical knowledge + sum score of practical skills + score of willingness to use cervical ultrasound in the future)/7. Results Beginners'comprehensive learning score at the three time points were 2.9±1.3, 4.8±1.8, 5.7±1.8,F(2,22)=52.11,P＜0.001,partial Eta squared=0.83. After introducing the route map, their comprehensive learning score increased 1.0(95% CI:0.46-1.49)(P＜0.001) compared to scores after traditional training. Conclusions The route map may significantly improve learning effectiveness and confidence of beginners in the field of cervical spinal ultrasonography and can be used as a routine training tool in the teaching of cervical spinal ultrasonography. [ABSTRACT FROM AUTHOR]

The Ag2S/TNTs hydrogen evolution electrode was prepared by chemical bath deposition of Ag2S on highly ordered TiO2 nanotubes (TNTs) using sodium sulfide and silver nitrate as starting materials. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to characterize the electrodes. The results showed that Ag2S particles were uniformly deposited on the surface of TiO2 nanotubes without destroying the original morphology and structure of the nanotubes. The hydrogen evolution performance of the composite electrode with different deposition cycles of Ag'S was analyzed by linear sweep voltammetry (LSV), Tafel curve, double layer capacitance analysis and electrochemical impedance spectroscopy (ETS) at room temperature of 0.5 mol/L H2SOq. Compared with TNTs, Ag2S/TNTs showed better hydrogen evolution performance. When the number of Ag2S deposition cycles is 9, the overpotential of the prepared composite electrode reaches 288. 14 mV at the current density of 10 mA/cm², the Tafel slope is 61.8 mV/dec, the double layer capacitance is 54.7 mF/cm², and the internal resistance of charge transfer is reduced to 0.7 Q/cm². [ABSTRACT FROM AUTHOR]