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Background: Compared with other types of compressors, although the scroll compressor has a simple structure and low noise, due to the limitation of the structure, it has defects such as excessively high discharge temperature, and has extremely high requirements on the machining accuracy of parts. The oil-free scroll compressor is a new type of scroll machine, which does not contain oil during the working process; it can be applied to cases with low displacement requirements and a high-pressure ratio. Objective: Taking a scroll compressor with a rated displacement of 0.6 m3/min as the research object, the analysis and research of the working performance parameters of the scroll compressor in actual work provide a certain theoretical basis for the improvement and optimization of the test prototype. Methods: The thermodynamic model of the scroll compressor in the actual working process is established by the variable-mass system thermodynamics and the control volume method. Based on the CFD method, a three-dimensional unsteady-state numerical simulation of the flow characteristics of the working fluid in the scroll compressor's working chamber is carried out in order to verify the thermodynamic model. Considering the accuracy of numerical simulation, a test platform with air as the working fluid is set up. Results: Through the thermodynamic model and numerical simulation, the changes of temperature, pressure and velocity in the working chamber of the scroll compressor with the orbiting angle of the main shaft as well as the gas force and torque acting on the orbiting scroll tooth are obtained. Through experiments, the law of volume flow and shaft power of the scroll compressor with the speed of change, and the law of the change of discharge temperature with pressure at different speeds are obtained. Conclusion: At the same time, the thermodynamic model established by considering heat transfer and leakage is more in line with the actual working process of the compressor; the mass exchange between adjacent working chambers of the scroll compressor has a greater impact on the temperature and pressure in the working chamber. Due to internal leakage and irreversible loss, such as heat transmission, there is a deviation between the theoretical volume flow and the actual volume flow.

Background: Heat pump air conditioning technology has broad application prospects and high market value in the field of electric automobiles owing to its increasing performance and energy saving. Pure electric vehicles require high-energy consumption at low temperatures, which seriously affects the popularity of electric vehicles with a heat pump air conditioning system. Objective: The aim of this research is to describe the recent developments in the study of the heat pump air conditioning system for electric vehicles. Methods: This paper summarizes the research work of scholars published worldwide based on the electric vehicle heat pump air conditioning system, premised on lately published patents and journal articles. Starting from the components of the air conditioning system, focusing on the research results and development trends that have been achieved in this field. Results: The new technology path and pattern of the electrical vehicle heat pump air conditioning system provide methods and suggestions for future growth, put forward by the current development situation. Conclusion: The latest progress of the electric vehicle heat pump air conditioning system has been summarized and prospected. There are still some problems and technical bottlenecks in heat pump air conditioning system. It is of great significance to improve the environmental adaptability of electric vehicles and optimize the reasonable heat pump air conditioning system for the endurance of electric vehicles.

In general, two-dimensional semiconductor-based van der Waals heterostructures (vdWHs) can be modulated to achieve the transition of band alignments (type-I, type-II, and type-III), which can be applied in different applications. However, it is rare in three-dimensional perovskite-based vdWHs, and it is challenging to achieve the tunable band alignments for a single perovskite-based heterostructure. Here, we systematically investigate the electronic and optical properties of all-inorganic perovskite vdWHs CsSnBr3/WS2(1-x)Se2x based on density functional theory (DFT) calculation. The calculated results show that the transitions of band alignment from type-II to type-I and type-III to type-II are achieved by modulating the doping ratio of the Se atom in the WS2(1-x)Se2x monolayer for SnBr2/WS2(1-x)Se2x and CsBr/WS2(1-x)Se2x heterostructures, respectively, in which the CsBr and SnBr2 represent two different terminated surfaces of CsSnBr3. The change of band alignments can be attributed to the conduction band minimum (CBM) transforming from the W 5d to Sn 5p orbital in SnBr2/WS2(1-x)Se2x vdWHs, and the valence band maximum (VBM) and CBM change from an overlapped state to a separated one in CsBr/WS2(1-x)Se2x vdWHs. This work can provide a theoretical basis for the dynamic modulation of band alignments in perovskite-based vdWHs.

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract resulting from the homeostasis imbalance of intestinal microenvironment, immune dysfunction, environmental and genetic factors, and so on. This disease is associated with multiple immune cells including regulatory T cells (Tregs). Tregs are a subset of T cells regulating the function of various immune cells to induce immune tolerance and maintain intestinal immune homeostasis. Tregs are correlated with the initiation and progression of IBD; therefore, strategies that affect the differentiation and function of Tregs may be promising for the prevention of IBD-associated pathology. It is worth noting that tryptophan (Trp) metabolism is effective in inducing the differentiation of Tregs through microbiota-mediated degradation and kynurenine pathway (KP), which is important for maintaining the function of Tregs. Interestingly, patients with IBD show Trp metabolism disorder in the pathological process, including changes in the concentrations of Trp and its metabolites and alteration in the activities of related catalytic enzymes. Thus, manipulation of Treg differentiation through Trp metabolism may provide a potential target for prevention of IBD. The purpose of this review is to highlight the relationship between Trp metabolism and Treg differentiation and the role of this interaction in the pathogenesis of IBD.

High transaction costs caused by dispersed and fragmented tracts, insecure tenure and incomplete information in rural land market has become a common issue in the transition economies. Horizontal integration may economize on transaction costs but aggrandize governance inputs. Therefore trade-off between integration and governance is one of the biggest challenges in land commercialization and rural restructuring worldwide. Resorting to a field survey in Nanhai District, Guangdong Province, this work estimates how the transaction costs of rural collective construction land are influenced by the horizontal integration degree and the level of self-organization governance of collectives. Four Tobit models are constructed based on the scale of collectives and the results show that: (1) There is an almost U-shaped relationship between the horizontal integration degree of the collectives and the transaction costs. The horizontal integration among shareholders can not only centralize the fragmented land assets from individual farmers and reduce the transaction costs of rural construction land, but also result in organization costs. The transaction costs are not decreasing as the horizontal integration increases until the transaction costs saved are equal to resultant organization costs. (2) The more collective leaders, the higher organization costs and the more opportunism behaviors, which will give rise to the transaction costs. This suggests that the Chinese authorities should strengthen the ongoing efforts to reduce the transaction costs of market and improve the efficiency through a more transparent and accessible market and optimal scale of horizontal integration of the collective. Our work sheds some light on the mechanisms at play in the reform and innovation of rural grass-root governance and it contributes to a better understanding of land-based shareholding cooperation system and nature of ongoing rural construction land market in China and transitional economies.

China has been characterized by sharp regional differences in quality of higher education. Using the data from a field survey on the entrepreneurial intentions of Chinese college students, this work adopts the Oaxaca–Blinder decomposition method to assess the extent and the determinants of the disparity of entrepreneurial intentions of college students from rural and urban areas. The analysis shows that both endowment and coefficient effects contribute to the rural–urban gap in entrepreneurial intentions of college students. This suggests that, though the different entrepreneurial intentions are mainly the result of the different personal qualities, more profound works are required to encourage the entrepreneurial intentions of college students from rural and urban areas.

Today East Asia harbors many “relict” plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species’ chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species., We acknowledge funding by the Global Environmental Research (S-14) of the Ministry of the Environment (Japan), the Proyecto Intramural Especial, PIE (grant no. 201630I024) from the CSIC, Spain, the Natural Science Foundation Project of CQ CSTC (cstc2016jcyjA0379) (China), and the Northeastern Research Institute of Petrified Wood and Mineral Resources, Nakhon Ratchasima Rajabhat University (Thailand).

the geometric model and gas force model of single-wrap scroll compressor and double-wrap scroll compressor are established, and the advantages and disadvantages of the two kinds of models in geometric performance and stress are compared and analyzed. The changes of shaft power, displacement, pressure and temperature in the working process of the two models are simulated. The prototype of double-wrap scroll compressor is developed, and the test platform is built for testing. The results show that the performance of the double-wrap scroll compressor is better than that of the single-wrap scroll compressor when the parameters, the scroll plate diameter, base circle radius, tooth height and the area of exhaust hole are the same. The results of simulation and test are close to each other, which verify the correctness of the model and simulation.

Based on embedded system, this system designs and realizes the non-contact measurement of object size and shape. In this system, images are processed on the machine vision platform, while edge detection is performed using Canny operator. Hough transform is used to judge whether the object is circle, quaternion detection method is used to judge whether the object is rectangle. The system also uses radar to scan targets, and get their distance and size after using the embedded system to process the data. The system can automatically find a planar or three-dimensional target in a non-contact situation, quickly measure and display the distance, shape, and size of the planar target, identify the object in the database and measure the nearest distance.

Recently, all-inorganic two-dimensional (2D) Ruddlesden-Popper (RP) halide perovskites have drawn much attention due to their excellent stability in ambient air. However, their electronic and optical performance resulting from a wide bandgap and low carrier mobility have hindered their use in photodetectors. To overcome these limitations, in this work, taking advantage of hexagonal indium selenide ($\mathrm{In}\mathrm{Se}$) with a high electron mobility, we construct an atomically thin heterostructure. Density-functional-theory (DFT) calculations of the electronic and optical properties are performed for these heterostructures. The results demonstrate that the photodetection response spectrum of the heterostructures is significantly broadened as the bandgap decreases from 2.17 to 0.40 eV for the $\mathrm{In}\mathrm{Se}$/${\mathrm{Cs}}_{2}{\mathrm{Sn}\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ heterostructure. Moreover, the electron effective mass, ${m}_{e}^{\ensuremath{\ast}}$, is reduced from 1.13 ${m}_{0}$ to 0.41 ${m}_{0}$ for the $\mathrm{In}\mathrm{Se}$/${\mathrm{Cs}}_{2}{\mathrm{Ge}\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ heterostructure. The significant reductions in both the band gap and effective mass are determined to be related to the type-II band alignment, which favors the carrier separation at the interface. The physical mechanisms related to the usage of this material in photodetectors are also discussed. The proposed III--VI semiconductor InSe and all-inorganic 2D RP perovskite ${\mathrm{Cs}}_{2}X{\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ (X = $\mathrm{Pb}$, $\mathrm{Sn}$, and $\mathrm{Ge}$) heterostructures provide challenges and opportunities for designing high-performance photodetectors.

Curative resection of hilar cholangiocarcinoma (HC) is typically carried out using open surgery. In the present study, we examined the safety (postoperative complication) and effectiveness (resection margin status and patient survival) of minimally invasive surgery (MIS) for HC. This retrospective analysis included 158 patients receiving MIS for HC at 10 participating centers between December 2013 and November 2019. Patient demographics, surgical outcomes, and oncological outcomes were retrospectively analyzed. Clinical information obtained from 10 different clinical centers did not show any evident cohort-bias clustering. One hundred and twenty-six (79.7%) patients underwent LRHC, 12 (7.6%) patients underwent RARHC, conversion to an open procedure occurred in 20 (12.7%) patients. The operation time and estimated blood loss were 410.8 ± 128.9 min and 477.8 ± 706.3 mL, respectively. The surgical radicality of the 158 patients was R0, 129 (81.6%); R1, 20 (18.4%) and R2, 9 (5.7%). Grades I–II complications was occurred in 68 (43.0%) patients. Severe morbidity (grade III–V) occurred in 14 (8.7%) patients. The median overall survival in whole cohort was 25.4 months. The overall survival rate was 67.6% at year 1, 28.8% at year 3, and 19.2% at year 5. Comparing the first half of MISHC performed by each center with the following cases, the operation time and postoperative hospital stay does not decrease with the increasing cases. On literature review, MISHC is non-inferior to open surgery at least in perioperative period. In this Chinese MIS for HC multicenter study, the largest to date, long-term overall survival rates after MIS appear comparable to those reported in current open series. Further randomized controlled trials are necessary to assess the global impact of MISHC.

Cervical lymph node metastasis in patients with differentiated thyroid cancer affects postoperative recurrence and survival. Hypoparathyroidism is caused by parathyroid gland injury during thyroidectomy. Carbon nanoparticles can trace stained lymph nodes, aiding in thorough dissection of lymph nodes in the operation area. To reduce postoperative occurrence of hypoparathyroidism, the parathyroid glands and their functions (identified by negative imaging induced by carbon nanoparticles) are retained in situ. However, the safety and adverse effects of nanocarbon suspension in thyroid surgery have rarely been evaluated. In this report, we describe a patient with thyroid cancer who had carbon secretions in the trachea caused by nanocarbon suspension when tracheal intubation was performed under general anesthesia, and the inflatable balloon surface of the tracheal tube was covered with these secretions. The patient recovered without fever, cough, phlegm production, chest pain, hoarseness, or hypocalcemia-induced convulsions. No consensus has yet been reached on the most appropriate injection site, depth, dose, or waiting time for nanocarbons in thyroid cancer surgery. We believe that nanocarbon suspension is safe for use in thyroid cancer surgery, but the most appropriate injection depth should be based on the thickness of the thyroid gland tissue to avoid deep injection into the trachea.

The rapid economic development in China has been characterized by levels of productivity very heterogeneous across local areas. This work investigates a previously unexplored aspect of such heterogeneity by assessing the degree of within-industry allocative efficiency across provinces over the period 1998–2007. Using firm-level data on the Chinese manufacturing firms, we measure resource misallocation by computing the within-industry covariance between size and productivity at the provincial level. The results suggest that allocative efficiency varies considerably across areas and that some place-based factors strongly influence the distribution of resources across firms.

Maternal dietary supplementation during gestation and lactation improves the health of piglets. The purpose of this study was to determine the effect of different levels of methionine (Met) supplementation in the sows’ diet during late gestation and lactation on piglets. Thirty sows were randomly divided into three groups and fed the following diets from day 90 of gestation to day 21 of lactation: (a) control group (a basal diet containing 0.36% Met), (b) 0.48% Met group (a basal diet with additional 0.12% Met), and (c) 0.60% Met group (a basal diet with additional 0.24% Met). On day 21 after farrowing, piglets of average body weight (n = 10 per group) were selected for sample collection. The results showed that the 0.48% Met and 0.60% Met diets significantly lowered the malondialdehyde content in the piglets’ serum (P < 0.05). In addition, the glutathione peroxidase content was significantly increased in the 0.48% Met group (P < 0.05) and the total glutathione content was significantly reduced in the 0.60% Met group (P < 0.05) compared to the control group. Furthermore, Met supplementation of the sows’ diet was associated with alterations in 37 plasma metabolites in the piglets. In the piglets’ intestinal microbiota, the relative abundances of Phascolarctobacterium and Bacteroidetes in the 0.48% Met group were higher than those in the other two groups (P < 0.05). Our results suggest that a diet including 0.48% Met during late gestation and lactation can maintain the health of piglets by increasing the antioxidant capacity and changing the intestinal microbiota composition, but a higher level of Met supplementation may increase the potential risk to piglets.

The numerical model of the series isolation structure was established by using the finite element software to simulate the dynamic behavior of the series isolation structure after explosions occurred at different positions, and study the dynamic response and failure mode of the series isolation structure under explosion load. The results show that the vertical displacement and speed of the beams on each floor show a certain regularity with the passage of time. When columns at different positions encounter explosive loads, they will cause local collapse and damage of the structure, and the damage is mainly distributed in the longitudinal and transverse ranges where the columns are located. Compared with the inner column, the structural damage caused by the explosion load on the corner column and side column is more serious.

This book review introduces Marta Peris-Ortiz, Jaime Alonso Gomez, Jose M. Merigo-Lindahl, and Carlos Rueda-Armengot’s book entitled Entrepreneurial universities: exploring the academic and innovative dimensions of entrepreneurship in higher education. Entrepreneurship is an expression of the talent of human creation, and the concept of the entrepreneurial university is the most well-articulated item in the evolution of the university towards the requirements of the knowledge-based society. However, two main questions are still under-explored: what are the core features of entrepreneurial universities, and what kind of activities related to innovation and entrepreneurship does arise in academic setting? The book can be grouped into three main sections: one concerns the entrepreneurial education of students provided by entrepreneurial university; the sections confirm the entrepreneurial initiatives and activities of entrepreneurial universities, which contribute to innovation and technology transfer; and those involve entrepreneurial research in academic setting. The book explores the institutional aspects of entrepreneurship activities to establish entrepreneurial universities. The defect of this book is the slightly lack of longitudinal study and secondary data in entrepreneurial intention and orientation research.

Metric learning algorithms have been widely applied for hyperspectral image (HSI) dimensionality reduction and classification. One of the metric learning algorithms proposed recently is discriminative locality alignment (DLA). The DLA attacks the distribution nonlinearity of samples, and preserves the discriminative ability. However, the DLA needs to manually adjust a parameter called scaling factor and produce mutually correlated discriminant vectors that may lead to unsatisfactory classification results. In this letter, a modified DLA algorithm, i.e., quotient DLA (QDLA), is proposed to solve the problems outlined previously. Moreover, we extend QDLA to a novel exponential DLA (EDLA) algorithm, which can achieve a more effective transformation from a nonlinear mapping of original data into a new space. The classification results with HSIs demonstrate that the performances of the proposed EDLA are better than other related methods.

Transcatheter arterial chemoembolization (TACE) has become one of the first-line standard treatments for intermediate-advanced hepatocellular carcinoma, as well as an effective treatment for metastatic hepatic carcinoma. The majority of TACE-related complications are mild and acceptable to patients. Compared with conventional (C)-TACE, drug-eluting bead (DEB)-TACE allows permanent embolization of blood vessels, a slow continuous release of anti-tumour drugs in a locally targeted manner, and reduction of the systemic release of anti-tumour drugs, so that their adverse effects are significantly reduced. The general consensus is that DEB-TACE is safer and better tolerated by patients than C-TACE because serious complications after DEB-TACE are rarely reported. This current case report describes a rare case of diffuse biliary peritonitis secondary to rupture of a hepatic tumour after DEB-TACE. After the procedure, the patient presented with progressively worsening upper abdominal pain. As conventional management methods for the suspected tumour rupture failed, an emergency laparotomy was performed to remove the metastatic mass of differentiated hepatic adenocarcinoma. The patient remains under surveillance with no further complications. In our opinion, although DEB-TACE is safe and rarely has serious complications, caution should be exercised when this method is used to treat tumours that are located close to the liver surface.

The seismic response of a high-pier long-span continuous rigid frame bridge under the action of far-field long-period ground motions is studied. A numerical calculation model of a high-pier long-span continuous rigid frame bridge whose span layout is (95+170+95)m is established by using finite element software. According to the established wave selection criteria, 10 long-period far-field seismic records and 10 ordinary seismic records are selected from the strong earthquake record database. Using the dynamic time history analysis method, the seismic response of the bridge structure under the far-field long-period seismic record and the ordinary seismic record was obtained through calculation, and a comparative analysis was carried out. The results show that the seismic response of a high-pier long-span continuous rigid frame bridge under far-field long-period ground motions is significantly greater than that of ordinary ground motions, the effect of ground motion spectrum characteristics should be considered in seismic design of such Bridges.

The solar cell based on hybrid organic-inorganic halide perovskite has received considerable attention. One of the most important issues in the pursuit of further developments in this area is to obtain both a high carrier mobility and an excellent ability of light adsorption. In this paper, we investigate the electronic structure and electronic effective masses of the new non-toxic material CH3NH3GeCl3 by first-principle calculations. The results show that the absorption efficiency of CH3NH3GeCl3 is more superior to that of CH3NH3PbI3 in short wavelength region. We trace this result to the ferroelectricity caused by the more serious octahedral GeCl6− distortion. We also discover a new relationship between the carrier effective masses anisotropy and the anisotropy of electronic density of states along three principal directions. Moreover, while applied the isotropic compressive pressure, the absorption efficiency and carrier mobility of CH3NH3GeCl3 in orthorhombic phase are improved greatly due to changes of electronic structure. We speculate that these are general results of tuning of the carrier mobility by controlling the band gap and the electronic occupation along different directions, to obtain both a high carrier mobility and an excellent ability of light adsorption.

In order to investigate the performance of variable thickness scroll compressors, a detail mathematical modeling based on energy and mass balances is established in this two-part. In part I, the geometric modeling and thermodynamic modeling are developed. The profile based on circle involute, high order curve, and arc is built up using the base line method. The volume of working chambers from suction to discharge is defined. Thereafter, the evolution and derivative of the working chamber volume with respect to the orbiting angle are discussed. The energy and the mass balance for working chamber are described. Suction gas heating, radial and flank leakage, heat transfer between the working fluid, scroll wraps and plates are considered in the thermodynamic modeling. The established geometric modeling and thermodynamic modeling can provide better understanding of the variable thickness scroll compressor working process. The dynamical modeling and model validation are reported in part II.

There has been great interest inhow to boost the performance of perovskite solar cells effectively. Building heterostructures between layered two-dimensional materials and perovskites is a common way to achieve the goal. In this work, the electronic and optical properties of the MoS2/CsPbBr3 heterostructure are studied systematically by density functional theory calculations. The calculated results show that the heterostructure can effectively retain some of the excellent properties of individual MoS2 and CsPbBr3. Furthermore, the optical performance of the two kinds of interfaces—CsBr/MoS2 contact and PbBr2/MoS2 contact—is better than that of the individual perovskite layers. We attribute the increased light absorption to the type II electronic band alignment of the heterostructure, interfacial charge transfer, and electron-hole separation. This work may be beneficial for improving the properties of perovskite solar cells and may open a way for the theoretical exploration of inorganic perovskite–based heterostructures.

The incidence of tuberculosis is increasing worldwide, especially in developing countries. The prevalence of abdominal tuberculosis has been found to be as high as 12% in people with extrapulmonary tuberculosis. Peritoneal thickening and intestinal adhesions can occur in patients with abdominal tuberculosis. Inguinal hernias are extremely rare in people with abdominal tuberculosis; only 11 cases have been reported in the English-language literature, half of which involved pediatric patients. No definitive guideline on the management of such cases is available. In this report, we describe the unusual finding of an incarcerated inguinal hernia in an adult with abdominal tuberculosis and propose a therapy to treat this complicated disease based on our successful experience.

Electroluminescence devices based all-inorganic halide perovskite material with the excellent luminescence performance have been studied extensively in recent years . However, the important role for the electrodes of electroluminescence devices is payed few attention by theoretical and experimental studies. Appropriate electrodes can reduce the Schottky barrier height to decrease the energy loss, and prevent the metal impurities from diffusing into the perovskite material to generate deep impurity levels, which improves the luminous efficiency and lifetime of devices. In this paper, not only the interface effects between CsPbBr3 and common metal electrode (Ag, Au, Ni, Cu and Pt) are studied by first-principle calculations, but also the diffusion effects of metal electrode atom into the CsPbBr3 layer are also explored by nudged elastic band calculations. The calculated results show the metal Ag is more suitable for the cathode for CsPbBr3 electroluminescence devices, while the metal Pt is more applicable for the anode. Based on the overall consideration about the interface effects and diffusion effects of the CsPbBr3-metal electrode junctions, the essential principle is analyzed. The work provides theoretical guidance for how to select the right electrode for the electroluminescence performance of all-inorganic halide perovskite. The critical factor of Schottky barrier height between the electrode and the light-emitting semiconductor, and transition level generated by metal impurities also provide a valuable reference how to select the suitable electrodes for other electroluminescence devices.

Objective. Our objective was to explore whether the pregnancy rate (PR) was higher than usual after hysterosalpingo-contrast sonography (HyCoSy). Methods. We conducted a prospective observational study of 1,008 infertility patients, all of whom were examined by HyCoSy. The expected time for spontaneous pregnancy was at least 180 days after the HyCoSy exams. There were three types of HyCoSy results: type I, defined as both fallopian tubes patent; type II, defined as one fallopian tube patent with obstruction in the other; and type III, defined as both fallopian tubes obstructed. During the HyCoSy examinations, we recorded the mobility of the ovaries, injective resistance, and contrast agent venous intravasation. Before the examinations, we recorded each patient’s medical history, including maternal age, infertility type, median duration of menstrual cycle, dysmenorrhea, and parity number. Results. The PR was 19.44% within 180 days after HyCoSy and it was significantly higher in the first 30 days (6.35%) (P P P P >.05). However, multivariate analysis showed that patency of both fallopian tubes and the absence of injective resistance were independently associated with pregnancy. Conclusion. Some infertility patients conceived successfully and naturally not long after HyCoSy, most often in the first month after the examination. Multivariate analysis showed that patency of both fallopian tubes and the absence of injective resistance were independently factors associated with the ability to conceive after HyCoSy examination.

Metric learning methods have been widely used in hyperspectral image (HSI) classification. They can project higher dimensional feature vectors to lower dimensional vectors and get more accurate classification results. Recently, nearest feature line (NFL) embedding (NFLE) algorithm has been proposed in HSI classification. This method tries to embed the distance between a point and its NFL. However, the decreasing of the point-to-line (P2L) distance does not mean that the point-to-point (P2P) distance decreases. In some cases, the P2P distance may even increase, which results in poor classification performance. In this letter, a modified algorithm of NFL and point embedding (NFLPE) is proposed for HSI analysis. Unlike NFLE, which just constrains the P2L distance, NFLPE also imposes an additional constraint on the P2P distance. This additional constraint avoids the possibility that when the P2L distance decreases, the P2P distance increases. Classification experiments with HSI demonstrate its superiority to other related techniques.

Seminar has become an attracting teaching method in higher education in past few decades. To give a comprehensive picture of seminar in Chinese higher education, the bibliometrics and content analysis were employed to analyze the relevant articles indexed by the Chinese Social Science Citation Index between 2000 and 2016. The distribution characteristics of literature quantity, published journals and research institutions were revealed in bibliometrics analysis. The law of change on research field, research type and research topics were described in content analysis. This study provides some reference for related research and also suggests directions for further work.

Background Malignant peripheral nerve sheath tumors (MPNSTs) arise from a peripheral nerve or display nerve sheath differentiation. Most MPNSTs typically originate on the trunk, extremities, head, neck, and paravertebral regions. Gastrointestinal MPNSTs are rare entities with only 10 cases reported worldwide in the literatures. Case presentation Here, we report the first Chinese case of a malignant peripheral nerve sheath tumor of the distal ileum presenting as intussusception. A 53-year-old female patient without pathological antecedent for neurofibromatosis was admitted with pain in the right lower abdomen and multiple episodes of vomiting for 1 week. Preoperative diagnosis was intussusception with a contrast-enhanced computed tomography scan (CECT) of the abdomen showing characteristic target sign. Due to difficulty reducing the ileum-colon intussusception, right hemicolectomy with ileocolostomy was performed. Histopathology was suggestive of low-grade MPNST. The patient received postoperative care and was followed up for 9 months. There is no sign of tumor recurrence and metastatic disease. Conclusions This case is unique in terms of a rare tumor presenting with unusual complication.

Background/Aims Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP. Methods SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR. Results CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores. Conclusions The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP.

We propose and investigate a compact gradient index plasmonic ring resonator (Grin PRR) with strong light confinement and extinction ratio based on finite element method (FEM). Theoretical simulation reveals that the change of index gradient influences the resonant frequency, Q factor and the mode volume. Significantly, it is demonstrated that the extinction ratio of Grin PRR can be optimized by varying the index gradient for any radius. Index gradient can enhance extinction ratio at settled size, so this structure has both high extinction ratio and smaller size footprint. It could be very promising for the high-density optical integration.

The research of improvisation has been become an emerging management area in recent years, and the purpose of this study is to explore the intellectual structure of this research domain. A journal co-citation analysis was performed using the cited articles in the improvisation field included by Web of Knowledge database from 1997 to 2012. The journal set used was the 30 most productive journals in the field of improvisation, and multivariate statistical techniques were used to deal with the co-citation frequency matrix and correlation matrix. The results of current study show that the knowledge base of improvisation research involves multi-disciplinary with broad relations with other specialties: management, organization, marketing, innovation, information management, sociology and psychology.

Despite years of research on new product development suggesting that development speed is an important prerequisite for product success, the empirical results show conflicting conclusion. To offer much needed clarity, this study use a meta-analysis approach allowing the systematic integration of 45 empirical findings from existing research. The findings reveal that development speed has a positive impact on product success. Using subgroup analysis and meta-regression analysis, results show that the culture and industry characteristics, research level, informants and variables measurement are found to moderate the relationship between speed and new product success. These findings have important implications for further research.

To overcome disadvantages of complex wiring and difficult maintenance for traditional wired sensor networks, a data acquisition system for chemical equipment monitoring based on wireless sensor network has been put forward. The proposed data acquisition system has functions of real-time data acquisition, transmission, storage, query and remote sharing of history data, and provides favorable technical supports for real-time chemical equipment monitoring. First, the system framework, EMBV210 hardware are introduced. Then, in the LabVIEW platform, the data acquisition system is developed, and the remote sharing of equipment operating status by DataSocket is realized. Finally, the proposed data acquisition system is simulated and verified. The work provides a feasible way for chemical equipment monitoring and useful references for the development of other similar integrated measurement and control systems.

Using penetration resistance methods detect the wall’s mortar strength to masonry structure where in ecological farm of Sichuan Emei, and then obtain the date of field trial. We have calculated the mortar actual strength according technical specification for testing compressive strength of masonry mortar by penetration resistance method, and compare the calculated results with compression tests result, testing specimen from the engineering project field. So we obtain true mortar strength of engineering and corresponding appraisal conclusion.

Given the shrinking proportion of agriculture output and the growing mobility of the labor force in China, how agricultural labor productivity develops has become an increasingly attractive topic for researchers and policy makers. This study aims to depict the development trajectory of agricultural labor productivity in China after its WTO entry. Based on a balanced panel data containing 287 Chinese prefectures from 2000 to 2013, this study applies the Latent Growth Curve Model (LGCM) and finds that the agricultural labor productivity follows a piecewise growth path with two breaking points in the years of 2004 and 2009. This may stem from some exogenous stimulus, such as supporting policies launched in the breaking years. Further statistical analysis shows an expanding gap of agricultural labor productivity among different Chinese prefectures.

Macleaya cordataextract is of great scientific and practical interest to researchers, due to its antimicrobial and anti-inflammatory responses within experimental animals. This study was designed to determine the diarrhea score and innate immunity of growing piglets after they had receivedMacleaya cordataextract supplements. A total of 240 growing pigs were randomly assigned to one of three dietary treatments, with 8 replicates per treatment and 10 piglets per replicate. All pigs received a basal diet containing similar amounts of nutrients. The three treatments were a control (no additive), an antibiotic (200 mg/kg colistin), and theMacleaya cordataextract supplement group (40 mg/kgMacleaya cordataextract). The diarrhea score was calculated after D 28. The jejunal samples were obtained from five piglets selected randomly from each treatment on D 28. In comparison with the control group, the dietaryMacleaya cordataextract and colistin group demonstrated a substantially decreased diarrhea score. The introduction ofMacleaya cordataextract supplements to the diet significantly increased volumes of ZO-1 and claudin-1, particularly in comparison with the pigs in the control group (P<0.05). The findings indicate thatMacleaya cordataextract does enhance intestinal barrier function in growing piglets and that it could be used as a viable substitute for antibiotics.

A theoretical study is presented on the dynamics of polaritons in semiconductor microcavities near parametric instability thresholds. With upward or downward ramp of optical pump, different instability modes emerge in parameter space defined by damping and detuning. According to these modes, stationary short-wave, stationary periodic, oscillatory periodic, and oscillatory uniform parametric instabilities are distinguished. By multiple scale expansion, the dynamics near threshold can be described by a critical mode with a slowly varying amplitude for the last three instabilities. Furthermore, it is found that the evolutions of their amplitudes are governed by real or complex Ginzburg–Landau equations.