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Background Coupled with the importance parents attach to education in Chinese culture, which makes adolescents bear more pressure. Academic stress has always been one of the central pressures faced by Chinese adolescents, and there is a strong link between academic stress and the non-suicidal self-injury (NSSI) behavior of Chinese adolescents. Methods A cross-sectional study was conducted in 10 selected middle schools in Guangxi Province, China, to examine the relationship between academic stress and adolescents' NSSI behavior and further analyze the relationship between adolescents' self-efficacy and parental support in stress and NSSI. A total of 2344 children were included in the analysis, including 1142 boys (48.72%) and 1202 girls (51.28%). Results The prevalence of NSSI was not significant among adolescents of different ethnic groups (t=-1.48, p = 0.139), but academic stress had a positive effect on adolescents' NSSI behavior (R = -0. 246, p

Background Due to China's large population and uneven distribution of educational resources, teenagers are faced with various competitions from birth, coupled with the importance parents attach to education in Chinese culture, which undoubtedly makes teenagers bear more pressure. Academic stress has always been one of the main pressures faced by Chinese adolescents, and there is a strong link between academic stress and non-suicidal self-injury (NSSI) behavior of Chinese adolescents. Methods a cross-sectional study was conducted in 10 randomly selected middle schools in Guangxi Province, China to examine the relationship between academic stress and adolescents' NSSI behavior, and to further analyze the relationship between adolescents' self-efficacy and parental support in stress and NSSI. A total of 2344 children were included in the analysis, including 1142 boys (48.72%) and 1202 girls (51.28%). Descriptive statistics will be used to understand the levels of adolescents' NSSI, academic stress, self-efficacy, and parental support; T-tests will be used to compare differences in adolescents' NSSI across demographic characteristics, academic achievement, and family economic status. A multiple linear regression model was used to examine the interaction between academic stress and NSSI in terms of adolescents' self-efficacy and parental support. Results The prevalence of NSSI was not significant among adolescents of different ethnic groups (t=-1.48, p = 0.139), but academic stress had a positive effect on adolescents' NSSI behavior (R = -0. 246, p

In mainland China, dialysis for children with end-stage renal disease (ESRD) was not introduced until the 1980s. To describe the development of pediatric dialysis in different regions of China, a national pediatric dialysis network, namely, International Pediatric Dialysis Network-China (IPDN-China) ( www.pedpd.org.cn ), was launched in 2012. Original and updated information from the renal centers registered with the IPDN-China was collected between 2012 and 2016 from two sources, namely, the registry and the survey, and demographic features were analyzed. Due to promotion by the IPDN-China, the number of registered renal centers increased from 12 to 39 between 2012 and 2016, with a significant increase in the coverage of the Chinese administrative divisions (from 26.5 to 67.6%) (p < 0.01); and the coverage of the pediatric (0~14 years old) population increased to nearly 90% in 2016. The distribution of renal centers indicated that East China had the highest average number of registered centers per million population (pmp) 0~14-year-old age group. Seventeen relatively large dialysis centers were distributed across 14 divisions. Various modalities of renal replacement therapy (RRT) were available in most centers. The IPDN-China has promoted collaborations between dieticians, psychologists, and social workers on dialysis teams to provide better service to children with ESRD and their families. The proportion of centers with all three types of paramedic support (i.e., dieticians, psychologists, and social workers) as well as the proportion of centers with a partial paramedic team significantly increased between 2012 (25.0%) and 2016 (69.2%) (p < 0.05). In terms of the point prevalent cases of patients (aged < 18 years), data from the survey of 39 registered centers revealed that the number of children with ESRD who were on RRT was 578 (49% received a kidney transplant) at the end of 2016, which was more than that reported in previous surveys. Data from the registry showed that 349 dialysis patients had been enrolled as of the end of 2016. The median age at RRT start was 9.5 years, and the leading cause of ESRD was congenital abnormalities of the kidney and urinary tract (CAKUT). The IPDN-China has helped to promote the development of pediatric dialysis for ESRD in China by improving the organization of care for dialysis patients and increasing the availability and the quality of RRT for patients who need it. To improve knowledge about the epidemiology and outcomes of pediatric RRT around the country, a sustained effort needs to be made by the IPDN-China to increase the enrollment of dialysis patients and increase the number of registered centers in the future.

Most turbulence models used in Reynolds-averaged Navier-Stokes (RANS) simulations are partial differential equations (PDE) that describe the transport of turbulent quantities. Such quantities include turbulent kinetic energy for eddy viscosity models and the Reynolds stress tensor (or its anisotropy) in differential stress models. However, such models all have limitations in their robustness and accuracy. Inspired by the successes of machine learning in other scientific fields, researchers have developed data-driven turbulence models. Recently, a nonlocal vector-cloud neural network with embedded invariance was proposed, with its capability demonstrated in emulating passive tracer transport in laminar flows. Building upon this success, we use nonlocal neural network mapping to model the transport physics in the k-epsilon model and couple it to RANS solvers, leading to a PDE-free eddy-viscosity model. We demonstrate the robustness and stability of the RANS solver with a neural network-based turbulence model on flows over periodic hills of parameterized geometries. Our work serves as a proof of concept for using a vector-cloud neural network as an alternative to traditional turbulence models in coupled RANS simulations. The success of the coupling paves the way for neural network-based emulation of Reynolds stress transport models.

Photon-number-resolving (PNR) is an important functionality in many applications. The traditional single photon detectors (SNSPDs) operated with the conventional readout scheme does not have the PNR functionality. In this paper, we demonstrate a superconducting photon-number-resolving detector operating at the visible wavelength regime, based on the serial connection of six superconducting nanowires. The results of our 6-element PNR device show clear evidence of n -photons differentiation with n ranging from 1 to 6. The system detection efficiency reaches 54% with the dark counts rate below 10 Hz at 660 nm. The demonstrated 6-element PNR device does not require a complex readout circuit compared with the SNSPD array device, and is expected to have wider applications in addition to imaging and communication.

Staphylococcus haemolyticus (S. haemolyticus) is a coagulase-negative Staphylococcus and has become one of the primary pathogens of nosocomial infections. After a long period using the antibiotics against the infections caused by S. haemolyticus, S. haemolyticus developed several resistance phenotypes of macrolides and lincosamides. Here, we acquired four S. haemolyticus clinical isolates, of which three isolates demonstrated antibiotic resistance as reported previously, while one was resistant to both erythromycin and clindamycin without erythromycin induction. Such novel phenotype, known as constitutive Macrolides-Lincosamides-Streptogramins (MLS) resistance, was reported in other bacteria, but it was found for the first time in S. haemolyticus. To further investigate such behavior, we confirmed that the deletion of the methyltransferase ErmC upstream leader peptide was critical to cause constitutive MLS resistance based on the analysis of potential antibiotic resistance genes via whole-genome sequencing and experimental verification. In addition, we discovered that the continuous expression of ErmC may inhibit the growth of S. haemolyticus, which turned out to be the cost with no MLS pressure. Taken together, this study firstly reported the constitutive MLS resistance in S. haemolyticus, and provided new ideas for using macrolides and lincosamides in clinical treatment.

Background NLRP3 and NLRP1 inflammasomes signaling pathways may play an important role in the development and progression of type 1 diabetes mellitus (T1DM). However, relative research is rare. Methods The blood mononuclear cells (PBMCs) and granulocytes (GCs) were collected from T1DM patients. The mRNA and protein expression levels were detected by qRT-PCR and Western blotting, respectively. The NLRP3/NLRP1was knocked down by transfected with siRNA, or ovexpressed by infected with lentiviral vectors in PBMCs and GCs from non obese diabetic (NOD) mice, respectively. The occurrence of diabetes was evaluated and the intraperitoneal glucose tolerance was tested in NOD mice with IL-1 receptor-associated kinase-M deficiency (IRAK-M −/− ). The pancreas and lymphonodus of IRAK-M −/− NOD mice were also collected for detection of NLRP3/NLRP1 expression. Results NLRP3, NLRP1, Caspase-1and IL-1β were significantly downregulated in the PBMCs and GCs of patients with T1DM, and NLRP3 and NLRP1 were markedly downregulated in T1DM patients with DKA compared to that with ND and CC. Further study indicated that IL-1β mRNA expression level was positively correlated with the expression levels of NLRP3, NLRP1 and Caspase-1. Besides, NLRP3/NLRP1 knockdown decreased the expression levels of Caspase-1 and IL-1β; whereas NLRP3/NLRP1 overexpression increased the expression levels of Caspase-1 and IL-1β in vitro . IRAK-M −/− NOD mice had early onset and rapid progression of T1DM, and weak glucose tolerance, which was regarded as an early T1D mouse model. The mRNA expression levels of NLRP3, NLRP1, Caspase-1and IL-1β in the pancreas and lymphonodus of IRAK-M −/− NOD mice were significantly higher compared to that of IRAK-M +/+ NOD mice. Conclusion NLRP3 and NLRP1 inflammasomes signaling pathways were associated with the development and progression of T1DM, which response as protective factors in the early stage of T1DM.

In this paper, we propose a structure of a superconducting nanowire single-photon detector (SNSPD) with a composite cavity. Compared with the SNSPD in previous studies, our device exhibits a property of high efficiency and dual broadband. Based on the transmission line theory, the structure is abstractedly expressed as an equivalent circuit model and a design method is presented. Taking λ = 1310nm and λ = 1550nm as an example, the structural parameters are calculated and verified by commercial software FDTD Solutions. The simulation results show that peaks of the absorption curve appear at both wavelengths and peak values are all larger than 97.5%. The influence of the upper half cavity on the full width at half maximum (FWHM) of the absorption peak is discussed. Our works provide a reference for designing an SNSPD with different FWHM.

In this article, we demonstrate a superconducting nanowire single photon detector (SNSPD) at a wavelength of 2000 nm. We use numerical simulations to optimize the parameters of the device structure. Guided by the obtained numerical results, we fabricated and measured the device that operates at 2000 nm at 2.3K. The results indicate that our device responses well in 2000nm with a dark count rate of 100Hz. The recovering time is 100ns.

The optical coupling of superconducting nanowire single-photon detectors (SNSPDs) has always been restricted to a single-mode fiber for a limited detection area. In this study, for enhancing photon coupling, a dual-lens system operating at 2.2 K was used to compress the beam size on the basis of the Gaussian beam theory and geometric approximation. A magnification of approximately 0.3 was obtained, and a focused spot with diameter of approximately 10 μm was measured from a multimode fiber. Assisted with the compressed beam, a system efficiency of 55 % (1550 nm) was achieved for a SNSPD with a detection area of 10 μm × 10 μm and 62.5 μm multimode fiber coupling. At the same time, a high speed of 106 MHz was measured with the proposed system. The realization of a highly compressed optical beam reduced the optical coupling requirement and helped maintain a high speed for the SNSPD.

In this paper, a superconducting nanowire single photon detector (SNSPD) is expressed as an equivalent circuit model. Combined with the theory of transmission line and impedance matching, the model is analyzed and a method is presented to design a SNSPD with high efficiency and dual broadband. Take the λ=1310 nm and λ=1550 nm as an example, geometry parameters of the device are calculated by this method and verified by the commercial software FDTD Solutions.

Superconducting nanowire single photon detectors (SNSPDs) deliver superior performance over their competitors in the near-infrared regime. However, these detectors have an intrinsic polarization dependence on the incident wave because of their one-dimensional meander structure. In this paper, we propose an approach to eliminate the polarization sensitivity of SNSPDs by using near-field optics to increase the absorption of SNSPDs under transverse magnetic (TM) illumination. In addition, an optical cavity is added to our SNSPD to obtain nearly perfect absorption of the incident wave. Numerical simulations show that the maximum absorption of a designed SNSPD can reach 96% at 1550 nm and indicate that the absorption difference between transverse electric (TE) and TM polarization is less than 0.5% across a wavelength window of 300 nm. Our work provides the first demonstration of the possibility of designing a polarization-insensitive and highly efficient SNSPD without performing device symmetry improvements.

BackgroundWe aimed to evaluate right ventricle (RV) function in children with primary nephrotic syndrome (PNS).MethodsRV hemodynamics were evaluated by Doppler echocardiography in 50 children with PNS (aged 2.5–12 years), either at PNS onset (n = 37) or relapse (n = 13), and in 50 normal controls. Heart rate, stroke volume, cardiac output, RV enddiastolic and end-systolic volume, RV ejection fraction, RV end-diastolic pressure, RV peak systolic and end-systolic pressure were determined from pressure-volume loops. The maximal rates of RV pressure upstroke and fall (dP/d tmax and dP/d tmin, respectively) were calculated. Effective pulmonary arterial elastance was calculated as end-systolic pressure divided by stroke volume. Plasma tumor necrosis factor-α (TNF-α) and insulin-like growth factor 1 (IGF-1) were also measured.ResultsRV end-diastolic pressure was increased by an average of 20% in 39 of the patients with PNS, whereas RV ejection fraction was reduced by an average of 15% compared with controls (p < 0.05 for both). Cardiac output and stroke volume were maintained, indicating compensation at the expense of increased RV end-diastolic and end-systolic volumes and increased RV filling pressure (p < 0.05). Plasma TNF-α was elevated in patients with PNS (326 ± 117 kU/L vs. 75 ± 23 kU/L, p < 0.05); IGF-1 was similar in PNS patients and controls.ConclusionRight ventricle function was impaired in children with PNS. The characteristics were unrelated to blood pressure and IGF-1, but may be correlated with TNF-α and disease duration. Further studies are needed to evaluate the etiology and clinical implications of this abnormality.

Polarization sensitive photo-detectors are the key to the implementation of the polarimetric imaging systems, which are proved to have superior performance than their traditional counterparts based on intensity discriminations. In this article, we report the demonstration of a superconducting nanowire single photon detector (SNSPD) of which the response is ultra-sensitive to the polarization state of the incident photons. Measurements carried out on a fabricated SNSPD show that a device efficiency of ~48% can be achieved at 1550 nm for the case of parallel polarization, which is ~420 times larger than that for the case of perpendicular polarization. While the reported polarization ultra-sensitive technique is demonstrated on a single-pixel SNSPD, it is also fully compatible with the multi-pixel SNSPD array platforms that emerged recently.

Superconducting nanowire single-photon detectors (SNSPDs) with a composite optical structure composed of phase-grating and optical cavity structures are designed to enhance system detection efficiency and count rates. Numerical simulation by finite-difference time-domain method shows that the photon absorption capacity of SNSPDs with a composite optical structure can be enhanced significantly by adjusting the parameters of the phase-grating and optical cavity structures. The absorption capacity of the superconducting nanowires reached 69.8% at the wavelength of 850 nm with 0.3 filling factor. When the filling factor was reduced to only 0.08, the absorption capacity is still 48.52%. It greatly decreased the kinetic inductance of SNSPDs, and improved the count rates.

Combining the current development situation of data mining system, this paper introduces the centralized and distributed data mining system respectively, focuses on the detailed introduce to the various components of the centralized data mining system and its concrete realization technology, and summarizes the current development situation of the centralized and distributed data mining system at the same time respectively, then puts forward the research direction and development trend of the data mining system: to enhance the visualization and interaction, to improve the scalability, , follow the single standard combined with a specific industry application and support of data mining of the mobile environment. The development of data mining system has been made into a brief summary and outlook. Data mining, also known as knowledge discovery in database (KDD), is that the process of digging out interesting knowledge from a large amount of data stored in the database, data warehouse or other information. In recent years, to promote the actual application of data mining, many researchers do a lot of research work on the architecture of data mining system. A data mining system with reasonable structure should have the following features: 1) completeness of system function and auxiliary tools; 2) scalability of system; 3) support for multiple data sources; 4) processing capabilities of the large amount of data; 5) good user interface and showing ability of the results. In the current, the data mining system mainly includes centralized and the distributed data mining system, and the specific structure and its various components of each system have a variety of different implementation techniques and methods. Centralized data mining system The single database/data mining system is the current data mining application system that has a more mature development, and many commercial data mining application software are based on the structure. From the analysis of the current main data mining system, it can be found that the specific implementation techniques of different products to various functional modules are not the same. User interface and knowledge presentation layer. In this layer, showing mining results by providing a friendly user interface and using the data visualization technologies can greatly improve the usability of the system. The visualization of data mining is to use visualization technology to find out implicit and useful knowledge from a large number of data set. The visualization of data mining mainly includes the visualization of data, mining process and mining model. The current visualization techniques mainly include the traditional geometry method (such as graph, histogram, scatter plot, pie charts, etc.) SOM network visualization technology, parallel coordinates technique, the visualization technology facing the pixels, etc. The visualization technology based on the SOM network and the parallel coordinate are the two that have more applications, and the principle of them are to display data in the two-dimensional plane through high-dimensional data mapping for two-dimensional data. Such as a visual mining system based on the SOM network VISMiner designed by Wang Jiacai and others, and Liu Kan and others studied the specific application of parallel coordinates technique in data mining system. Control layer. Control layer is used to control the execution flow of the system, and coordinate the relationship between each feature and their execution order, which mainly includes the analysis of data mining task, and judgment of data involved in mining tasks and data mining algorithm

Niobium nitride superconducting nanowire single-photon detectors were fabricated on thermally oxidized silicon substrates with large active areas of 30 μm × 30 μm. To achieve non-constricted detectors, we improved the film growth and electron beam lithography process to fabricate uniform 100-nm wide NbN nanowires with a fill factor of 50%. The devices showed 72.4% system detection efficiency (SDE) at 100-Hz dark count rate (DCR) and 74-ps timing jitter, measured at the fiber communication wavelength of 1550 nm. The highest SDE which is 81.2% when the DCR is ~700 c/s appears at the wavelength of 1650 nm.