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A radar system requires a number of high-power components operating in a narrow and convection-free environment. This study aims to develop an integrated heat dissipation system that is suitable for the high-power electronic equipment of radar systems. The proposed heat dissipation mechanism integrates a fluid circulation-type cold plate with a quad transmit receive module. The finite element method in the COMSOL fluid–solid coupling heat transfer analysis software was used to analyze the heat dissipation performance of the cold plate in the proposed mechanism. The Taguchi method was adopted to optimize the cold plate design. The simulation and experimental results show that the proposed mechanism can control the temperature equalization and temperature of the system within the specified requirements. The practicality of the proposed mechanism was verified. The findings can serve as a reference for the design of high-power electronic equipment in a heat dissipation system.

Osteosarcoma is the most common type of bone cancer in children and young adults. Recent studies have shown a correlation between epithelial-mesenchymal transition (EMT)-related gene expression and immunity in human cancers. Here, we investigated the relationship among EMT, immune activity, stromal activity and tumor purity in osteosarcoma. We defined EMT gene signatures and evaluated immune activity and stromal activity based on the gene expression and clinical data from three independent microarray datasets. These factors were evaluated by single sample Gene Set Enrichment Analyses and the ESTIMATE tool. Finally, we analyzed the key source of EMT gene expression in osteosarcoma using microarray datasets from the Gene Expression Omnibus and human samples that we collected. EMT-related gene expression was positively correlated with immune and stromal activity in osteosarcoma. Tumor purity was negatively correlated with EMT, immune activity and stromal cells. We further demonstrated that high EMT gene expression could significantly predict poor overall survival (OS) and recurrence-free survival (RFS) in osteosarcoma patients, while high immune activity cannot. However, combining these factors could have further prognostic value for osteosarcoma patients in terms of OS and RFS. Finally, we found that stromal cells may serve as a key source of EMT gene expression in osteosarcoma. The results of this study reveal that the expression of EMT genes and immunity are positively correlated, but these signatures convey disparate prognostic information. Furthermore, the results indicate that EMT-related gene expression may be derived from stromal rather than epithelial cancer cells.

Purpose To evaluate the effect of anesthetic management on scoliosis surgery and review the incidence rate of perioperative adverse events. Methods This was a retrospective study and approved by the ethics committee. Patients who underwent scoliosis surgery from April 2011 to March 2018 in the Third Hospital of ChengDu were enrolled in this study. Characteristics of patients were obtained from the hospital's electronic records. The following information on patients was collected: preoperative assessment details, premedication, type of anesthesia and operation, the main postoperative outcome, and complications. Data were presented as the mean ± standard deviations (SD) for normally distributed continuous variables and numbers for categorical variables. Statistical analyses were performed using SPSS version 22.0. Results In total, 513 patients were enrolled in the present study. The main preoperative complication was cardiopulmonary dysfunction (386 cases, 75.24%). Anesthesia induction was performed with conscious tracheal intubation after oral surface anesthesia. In total, the common postoperative complications involved anesthesia (24 cases, 4.68%), surgery (23 cases, 4.48%), the respiratory system (138 cases, 26.90%), and the gastrointestinal tract (nine cases, 1.75%). The majority of postoperative complications were postoperative hypoxemia and hypercapnia, caused by poor cardiopulmonary function. Rare and serious complications still occurred. Three patients died in hospital. Conclusion Our study demonstrated a high incidence of complications in scoliosis surgery, especially postoperative complications. Extreme postoperative vigilance is required and high‐level monitoring of conditions is highly recommended. This was a retrospective study with patients who underwent scoliosis surgery from April 2011 to March 2018 in the Third Hospital of ChengDu, aiming to evaluate the effect of anesthetic management on scoliosis surgery and review the incidence rate of perioperative adverse events. A total of 513 patients were enrolled in the present study. The main preoperative complication was cardiopulmonary dysfunction. And the common postoperative complications were related to anesthesia, surgery, the respiratory system, and the gastrointestinal tract. This study demonstrated a high incidence of complications in scoliosis surgery, especially postoperative complications, and indicated that extreme postoperative vigilance and high‐level monitoring conditions were needed for scoliosis surgery.

The objective of this study was to compare the clinical results and complications of proximal femoral nail antirotation (PFNA) on treatment of intertrochanteric fractures in 120 elderly Chinese patients using Randomized Controlled Trials (RCTs). Totaly 120 cases enrolled were randomly assigned to a lateral decubitus position group and supine position group. The hospital stay, operating time, intraoperative blood loss, length of incision, X-ray fluoroscopy time, and out-of-bed activity time in the lateral decubitus position group were significantly lower than those in the supine position group. There was not statistical significance on union time and Harris values in the two position groups. Moreover, only complications of superficial wound infection were observed in the lateral decubitus position group, but two complications of deep venous thrombosis and wound deep infection were found in the supine position group. The present findings suggested that PFNA applied in elderly patients with intertrochanteric fracture can get satisfactory effects, and the treatment of intertrochanteric fractures using lateral decubitus position showed a satisfactory clinical outcome and a lower radiological complication rate.

A new longitudinal attitude control system design for an unmanned seaplane in the severe sea states is presented in this paper. We develop a nonlinear passive observer, which is used to achieve wave filtering and state estimation. Moreover, the observer can be extended to achieve adaptive wave filtering in varying sea states. Using the estimated low-frequency states, a backstepping sliding mode controller is designed to keep the longitudinal attitude of the unmanned seaplane stable. The stability of the total closed loop system is analyzed by using Lyapunov theory. Simulations are performed in different wave conditions, including Seastate 3 and Seastate 5. The simulations results show that the proposed longitudinal attitude controller can improve the anti-waves capability effectively. Moreover, adaptive wave filter has a significant advantage over a filter with fixed model parameters in varying sea states.

An updated approach to refining the core indicators of pulverized coal used for blast furnace injection based on principal component analysis is proposed in view of the disadvantages of the existing performance indicator system of pulverized coal used in blast furnaces. This presented method takes into account all the performance indicators of pulverized coal injection, including calorific value, igniting point, combustibility, reactivity, flowability, grindability, etc. Four core indicators of pulverized coal injection are selected and studied by using principal component analysis, namely, comprehensive combustibility, comprehensive reactivity, comprehensive flowability, and comprehensive grindability. The newly established core index system is not only beneficial to narrowing down current evaluation indices but also effective to avoid previous overlapping problems among indicators by mutually independent index design. Furthermore, a comprehensive property indicator is introduced on the basis of the four core indicators, and the injection properties of pulverized coal can be overall evaluated.

The existence of cancer stem cells, stem-like cancer cells (SLCCs), or tumor-initiating cells is considered as the cause of tumor formation and recurrence, indicating the importance of studying novel therapy that targets SLCCs. The origin of SLCCs is controversial because of two competing hypotheses: SLCCs are either transformed from tissue adult stem cells or dedifferentiated from transformed progenitor cells. Our previous research demonstrates that SLCCs are inducible by increasing genomic instability in cancer cells. In this study, to block the emergence of SLCCs, aminoethyl isothiourea (AET), a compound that clears free radicals and is used to protect patients from radioactive exposure, was used as an agent that maintains genomic stability in combination with mitomycin C (MMC), a commonly used chemotherapeutic drug that damages DNA. Using a rabbit tumor model with VX2 hepatic carcinoma, we found that MMC alone increased lung metastases and disadvantaged survival outcome, but the combination of MMC and AET reversed this effect and even prolonged overall survival. Moreover, in a VX2 xenograft model by immunocompromised mice, MMC alone enriched tumor-initiating cells, but the administration of MMC in combination with AET eliminated tumor cells effectively. Furthermore, MMC alone enhanced genomic instability, but MMC combined with AET attenuated the extent of genomic instability in primary VX2 tumor tissue. Taken together, our data suggest that the genomic protector AET can inhibit the induction of SLCCs, and this combination treatment by AET and cytotoxic agents should be considered as a promising strategy for future clinical evaluation.

This paper presents a hierarchical simultaneous localization and mapping (SLAM) system for a small unmanned aerial vehicle (UAV) using the output of an inertial measurement unit (IMU) and the bearing-only observations from an onboard monocular camera. A homography based approach is used to calculate the motion of the vehicle in 6 degrees of freedom by image feature match. This visual measurement is fused with the inertial outputs by an indirect extended Kalman filter (EKF) for attitude and velocity estimation. Then, another EKF is employed to estimate the position of the vehicle and the locations of the features in the map. Both simulations and experiments are carried out to test the performance of the proposed system. The result of the comparison with the referential global positioning system/inertial navigation system (GPS/INS) navigation indicates that the proposed SLAM can provide reliable and stable state estimation for small UAVs in GPS-denied environments.

Background： Attention-deficit hyperactivity disorder （ADHD） is the most common mental and behavioral disorder in school-aged children. This study evaluated the effect of osmotic-release oral system （OROS） methylphenidate （MPH） on cognitive function and academic performance of Chinese school-aged children with ADHD. Methods： This 12-week, prospective, multicenter, open-label, self-controlled study enrolled 153 Chinese school-aged children with ADHD and 41 non-ADHD children. Children with ADHD were treated with once-daily OROS-MPH （18 mg, 36 mg, or 54 mg）. The primary endpoints were Inattention/Overactivity （I/O） with Aggression Conners Behavior Rating Scale （IOWA） and Digit Span Test at week 12 compared with baseline. Secondary endpoints included opposition/defiant （O/D） subscale of IOWA, Clinical Global Impression （CGI）, Coding Test, Stroop Color-word Test, Wisconsin Card Sorting Test （WCST）, academic performance on teacher-rated school examinations, and safety at week 12 compared with baseline. Both non-ADHD and ADHD children received the same frequency of cognitive operational test to avoid the possible bias caused by training. Results： A total of 128 patients were evaluated with cognitive assessments. The OROS-MPH treatment significantly improved IOWA Conners I/O subscale scores at week 12 （3.8 ± 2.3） versus baseline （10.0 ± 2.4; P 〈 0.0001）. Digit Span Test scores improved significantly （P 〈 0.0001 ） with a high remission rate （81.1%） at week 12 versus baseline. A significant （P 〈 0.0001 ） improvement was observed in O/D subscale of IOWA, CGI, Coding Test, Stroop Color-word Test, WCST, and academic performance at week 12 versus baseline. Very few practice-related improvements were noticed in the non-ADHD group at week 12 compared with baseline. No serious adverse events and deaths were reported during the study. Conclusions： The OROS-MPH treatment effectively controlled symptoms of ADHD and significantly improved academic performance and cognitive fimction of Chinese school-aged children with ADHD. The treatment was found to be sate and generally well-tolerated over 12 weeks.

The reduction of titanomagnetite（TTM） ironsand, which contains 11.41wt% TiO_2 and 55.63wt% total Fe, by graphite was performed using a thermogravimetric analysis system under an argon gas atmosphere at 1423–1623 K. The behavior and effects of titanium in TTM ironsand during the reduction process were investigated by means of thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. During the reduction procedure, the titanium concentrated in the slag phase, where the phase transformation followed this sequence： Fe O ＋ FeTiO_3 → Fe_2 TiO_4 → FeTiO_3 → FeTi_2O_5 → TiO_2. The calculated results for the reduction kinetics showed that the carbothermic reduction was controlled by the diffusion of ions through the product layer. Furthermore, the apparent activation energy was 170.35 k J·mol~（-1）.