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A 3-year-old female patient with no significant medical history presented to her pediatrician with foamy urine. Initial testing revealed moderate proteinuria on qualitative testing, although she was incidentally noted to have severe hypertension (240/200 mmHg). Physical examination of the carotid and femoral areas revealed significant systolic vascular murmurs. Labs showed elevated serum creatinine, hypokalemia, metabolic alkalosis, elevated renin and aldosterone and hypercalciuria. Echocardiography identified ventricular hypertrophy. Computed tomography (CT) of the abdomen and magnetic resonance angiography of the head showed multiple tortuous or interrupted arteries and multiple calcifications in the renal sinus area. B-mode ultrasonography suggested thickening of the carotid and femoral artery walls, with numerous spotted calcifications. Genetic testing revealed that ABCC6 had a complex heterozygous mutation (exon 24: c.3340C > T and intron 30: c.4404-1G > A). Our panel of experts reviewed the evaluation of this patient with hypertension, proteinuria, hypercalciuria, and vascular abnormalities as well as the diagnosis and appropriate management of a rare disease. [ABSTRACT FROM AUTHOR]

In this work, two different types of post-heat treatment processes were developed for additively manufactured CuCrZr alloy. The effect of post-heat treatment on the microstructure and properties of as-built CuCrZr alloy was studied in detail. After the direct aging of the as-built samples, the cellular substructure was preserved and a large number of fine Cu4Zr and Cr particles were precipitated in the matrix. However, after solid solution and age-hardening treatment, the grains in the sample coarsened to hundreds of microns and the annihilation of the cellular substructure occurred. Compared with the samples after solid solution and age-hardening treatment, the directly aged samples had an excellent combination of hardness (191 ± 7 HV), strength (513 ± 8 MPa) and electrical conductivity (82.2 ± 1.5 pct IACS). The high strength of the directly aged samples can be attributed to the enhancement of the strengthening mechanism of the precipitated particles and the retention of the cellular substructure. In addition, the reduction of solid solution atoms would significantly weaken the electron scattering effect, thereby improving the electrical conductivity. [ABSTRACT FROM AUTHOR]

At present, there are very few vibration test designs for compressor stator blades in damped blade test research, and there is a lack of consideration of the holding ring structure of the blade installation. In recent years, compressor designs have become more elaborate, and their structures have become more compact. For improving compressor stator blade design, it is necessary to study the blade vibration response considering contact and friction. In this paper, a compressor stator blade vibration test system with a holding ring structure is designed and built. The composition of the system and the flow of vibration are tested. Then, the nonlinear vibration rules of the model stator blades are experimentally studied through the built test bench. The experimental conditions include excitation forces of 1 N, 2 N, 3 N and 4 N, respectively. At the same time, the normal load of the outer holding ring and the blade contact surface includes 10 N, 20 N, 30 N and 40 N working conditions. The nonlinear vibration law of the test model blade considering contact friction is analyzed using a numerical method and experimental data. The experimental data agree well with the numerical analysis results, and the relative error of measurement is basically less than 5%. It is concluded that the damping vibration rule of the test model blade is related to the exciting force applied by the exciter and the contact surface normal load applied by the adjusting bolt. When these two parameters change, the movement behavior of the contact surface will switch between macro-slip, fretting slip and even a viscous state. Therefore, the amplitude of the blade will change and show nonlinear vibration characteristics. The experimental data in this paper can provide a reference for research on stator ring vibration safety in compressors. [ABSTRACT FROM AUTHOR]

There are many kinds of assembly structures in heavy-duty gas turbine compressor stator blades which have significant influence on the complex damping vibration characteristics. At present, compressor design is becoming more and more compact, so it is very meaningful to accurately obtain stator blade vibration characteristics of structures with contact damping. Firstly, a fretting slip friction dynamic model was introduced, and then a vibration analysis model of the compressor stator blade with outer ring structure was established based on the slip friction theory. Then, the vibration response of the compressor stator blade was obtained according to various working conditions, and the main factors affecting the vibration characteristics of the stator blade were revealed. Finally, the vibration response of the blade under a particular exciting force condition was simulated. The results show that the damping vibration characteristics of the compressor stator blades were affected by the excitation force and the normal load of the contact surface. The vibration response curve of the stator blade and the equivalent stiffness coefficient of the contact surface were analyzed, and the friction motion of the contact surface changed with the change of the working condition. The model can simulate the nonlinear vibration characteristics of stator blades. This method provides a reference for the vibration safety analysis of compressor stator blades. [ABSTRACT FROM AUTHOR]

Manufacturing abrasion‐resistant superhydrophobic matters is challenging due to the fragile feature of the introduced micro‐/nanoscale surface roughness. Besides the long‐term durability, large scale at meter level, and 3D complex structures are of great importance for the superhydrophobic objects used across diverse industries. Here it is shown that abrasion‐resistant, half‐a‐meter scaled superhydrophobic objects can be one‐step realized by the selective laser sintering (SLS) 3D printing technology using hydrophobic‐fumed‐silica (HFS)/polymer composite grains. The HFS grains serve as the hydrophobic guests while the sintered polymeric network provides the mechanical strength, leading to low‐adhesion, intrinsic superhydrophobic objects with desired 3D structures. It is found that as‐printed structures remained anti‐wetting capabilities even after undergoing different abrasion tests, including knife cutting test, rude file grinding test, 1000 cycles of sandpaper friction test, tape test and quicksand impacting test, illustrating their abrasion‐resistant superhydrophobic stability. This strategy is applied to manufacture a shell of the unmanned aerial vehicle and an abrasion‐resistant superhydrophobic shoe, showing the industrial customization of large‐scale superhydrophobic objects. The findings thus provide insight for designing intrinsic superhydrophobic objects via the SLS 3D printing strategy that might find use in drag‐reduce, anti‐fouling, or other industrial fields in harsh operating environments. [ABSTRACT FROM AUTHOR]

Nanofluids has become one of the most promising cooling fluids due to its great thermophysical properties, especially for microchannels. In recent years, to avoid prohibitively expensive simulations in design process or iterative optimization, massive data-driven and machine learning methods have been employed to construct surrogate models for thermophysical properties or concerned performance characteristics. Though the favorable accuracy is validated, this kind of surrogate models ignore the importance of physical fields, which are also an evaluating criterion in heat transfer design scenarios. In this article, we develop a deep learning framework to achieve the main task of real-time reconstruction mapping from design variables to physical fields. In addition, the auxiliary tasks of prediction mapping from physical fields to performance characteristics are tailored to improve the accuracy and generalization of reconstruction mapping. To validate the feasibility of this framework, we assess the ability of the generator alone to reconstruct physical fields and predict performance characteristics for the flow and heat transfer of nanofluid first. The results show that the introduction of auxiliary task can greatly improve the performance of main task. The computational performance analysis indicates that a well-trained deep learning model with GPU-accelerated has three orders of magnitude faster than CFD solver. This proposed approach was expected to provide a real-time predictor with a reasonable level of accuracy for nanofluid convective heat transfer. [ABSTRACT FROM AUTHOR]

Multi‐material additive manufacturing has become a promising trend in fabricating advanced functional architectures due to its controllable design of diverse material species and novel structures. It remains challenging to endow the multi‐material components with a mechanical‐to‐electrical conversion capability. This study reports on multi‐material selectively laser sintered magnetoelectric architectures that can convert mechanical energy to electricity in a structure‐dependent manner. The principal aim is to establish a relationship between the electrical output and the printed structures by fabricating a series of porous architectures with diverse structural parameters. The findings show that the output voltage increases with the decrease of the elastic modulus and the increase of the magnetic height, which has been analyzed by numerical simulation. Owing to the mechanical‐to‐electrical conversion capability, a pair of multi‐material printed sneakers with the functionalities of power generation and gait analysis has been prepared. The voltage output reaches as high as ≈2 V, which can lighten a light‐emitting diode lamp when a user is running. The described solution in this work has offered an exploration framework for the design, fabrication, and application prospects of multi‐material additively manufactured architectures. [ABSTRACT FROM AUTHOR]

Due to the complexity of the compressor operating conditions and the existence of various disturbances and unsteady effects in the flow field, the analysis of compressor stator vibration characteristics becomes particularly critical. The convolutional neural network model combined with a transient CFD method was introduced to solve the difficulty of analyzing the flow load of the compressor stator blade. This paper mainly focuses on two key points: the complex change of the aerodynamic load and the accurate prediction of the blade excitation. Considering the stator–rotor interference, the unsteady effects, and the variable working condition characteristics, the random disturbance analysis model of the flow field boundary was generated to simulate the unsteady flow excitation of the stator under complex working conditions. By establishing the neural network of boundary disturbance and flow excitation characteristics, the prediction model was trained and generated under the support of large-scale data. The most important role of the model was to establish the end-to-end data mapping between the disturbance condition and the aerodynamic load of the stator blade. The conclusions demonstrate that the introduction of an airflow disturbance is helpful to obtain the excitation characteristics of the stator under complex working conditions. The model established in this paper based on 1000 groups of disturbed working condition data can effectively predict the aerodynamic load of the blades under complex working conditions. In addition, the construction of the model is beneficial for saving a lot of computing resources, and the prediction accuracy also reaches a good level. The method presented in this paper provides a reference for the vibration analysis of the compressor stator. [ABSTRACT FROM AUTHOR]

The simultaneous placement of different types of materials including polymers, ceramics, and metals, in their desired positions could be adopted to manufacture end-use devices/apparatuses with diverse functionalities and significantly reduce the fabrication cost and time. However, existing additive manufacturing (AM) approaches can only treat one material species at a time due to their intrinsic working mechanisms. Here we develop an AM manipulator for manufacturing a wide variety of material species, including polymers, ceramics, and metals, through a multifilament transport strategy assisted by laser power. The six-jaw manipulator contains three pairs of filament delivering/cutting systems for transporting diverse materials and a beam of tunable laser as the thermal source. The whole apparatus is integrated into a robotic manipulator to create a multifreedom manufacturing platform. With this innovation, products with multiple material species and desired complex geometries can be fabricated on demand. Furthermore, we synthesize a multimaterial (polymer/ceramic/metal) printed magnetoelectric pressure sensor that can convert applied mechanical forces to electricity and maintain efficiency even after undergoing 10000 cycles of pressure/recovery. With this multimaterial filament transport and laser manufacturing strategy, our AM manipulator exhibits promising application in the advanced manufacturing of embedded electronics, sensors, soft robotics, and customizable medical devices. [ABSTRACT FROM AUTHOR]

In this study, in situ TiO2 was grown on the surface of graphene by a facile sol–gel method to form black TiO2/graphene composites with highly improved photocatalytic activity. The combination of graphene and TiO2 was beneficial to eliminate the recombination of photogenerated electron holes. The self-doping Ti3+ was introduced, accompanied by the crystallization of amorphous TiO2, during the hydrogenation process. Consequently, the narrowed bandgap caused by self-doping Ti3+ enhanced the visible light absorption and thus made the composites appear black. Both of them improved the photocatalytic performance of the synthesized black TiO2/graphene composites. The band structure of the composite was analyzed by valence band XPS, revealing the reason for the high visible light catalytic performance of the composite. The results proved that the black TiO2/graphene composites synthesized show attractive potential for applications in environmental and energy issues. [ABSTRACT FROM AUTHOR]

As a promising metalwork processing technology, electromagnetic induction heating (EMIH) method has been applied in dealing with bolted flange joints in turbomachinery. In this study, a 3-D finite element model of electromagnetic induction heating system for the bolted flange joint is established, and the specific governing equations are derived based on Maxwell's principle. The alternately-coupled magneto-thermal analysis is carried out considering temperature-dependent material properties to obtain the temperature distribution, followed with the uncoupled thermal-mechanical analysis to acquire the axial stress and deformation in EMIH process. The magnetic induction intensity mainly concentrates at the inner wall region, attenuates seriously along the radial direction, and reduces to almost zero at the outer wall. Due to the skin effect, the heat transfers radially and axially outward, indicating a diamondlike-shaped development from the center to the surrounding region. The axial stress with and without initial pretension are also discussed respectively. Then the corresponding experiments are introduced and carried out to validate the reliability of numerical simulation results. By comparing the results of the center point of inner surface and outer surface, the numerical simulation is proved reliable with a 5∼10% reasonable deviation. Further, the induction heating process has been improved through the optimization method based on pattern search algorithm. By adopting the stepped input current density optimized in the study, the optimal thermal stress tends to be constant and the final heating time reduces by 20.5% in the safe range of stress. [ABSTRACT FROM AUTHOR]

The rail clip fastening system is an important structural component of railway track systems providing flexibility and turnover resistance for running rails. High replacement frequency of fasteners was observed compared with other components because of fatigue failures of rail clips. In this study, implicit and explicit finite element (FE) models were developed for E‐clip and Fast‐clip with material and fatigue properties obtained from experimental testing. The fatigue loading experiments were conducted to determine the strain‐life relationship. The assessments of the fatigue damage and fatigue life were analysed using the FE results for the rail clip strain/stress components with the Fatemi‐Socie multiaxial fatigue criterion. A time‐efficient smallest enclosing circle algorithm was developed to search the critical plane orientation and the maximum shear strain amplitude for fatigue analysis. This work provides a method for FE and experimental study of multiaxial fatigue analysis of rail clip failures subjected to dynamic loading. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical characteristics and treatment of the Herlyn-Werner-Wunderlich syndrome (HWWS). Methods: Sixty-one patients diagnosed with HWWS were retrospectively analyzed. HWWS is categorized into three types in China. Results: Age at presentation of all the cases was after menarche. The most common clinical presentations were dysmenorrhea for type I and vaginal discharge for types II and III. Clinical presentations of types II and III may not occur until reproductive age. HWWS occurred on the right in 39/61. Excision of the obstructed vaginal septum was the treatment utilized in this cohort. After surgery, subsequent pregnancies were ipsilateral in 52.9 %. Conclusions: Clinical presentation in untreated HWWS suggests the anatomic anomaly. Early recognition and treatment can reduce symptoms. Pregnancies occur in both the affected and unaffected uterus. [ABSTRACT FROM AUTHOR]

A prospective study was designed to evaluate the efficacy of azithromycin (AZM) when combined with prednisone therapy compared with prednisone therapy alone in children with primary nephrotic syndrome (PNS) undergoing induction treatment. A prospective randomly controlled clinical trial was conducted. Randomization was performed to select the research subjects who were composed of children with PNS and treated with AZM combined with prednisone (the intervention group) and with prednisone alone (the control group). A total of 211 randomly selected patients with PNS received either AZM combined with prednisone ( n = 106) or prednisone alone ( n = 105) for 6 months. At three months in the follow-up period, 12 patients were lost to follow up (intervention group, 7; control group, 5), and 6 patients had a transient hypocomplementemia (intervention group, 4 ; control group, 2). AZM was administered at a dose of 10 mg/kg q.d (1 dose per day) for three consecutive days. The median duration before remission was 6 days in the intervention group and 9 days in the control group ( p < 0.0001). Relapse rate differed among the groups at 3 months (11.6 vs. 21.4 %, p = 0.049). No difference in relapse rate was observed between the two groups within 4 to 6 months and at 6 months ( p = 0.168, 0.052). After 4 weeks of treatment, steroid resistance occurred in 1 out of 95 (1.05 %) patients in the intervention group and in 10 out of 98 (10.2 %) patients in the control group ( p = 0.006). After 8 weeks of treatment, no difference was found in steroid resistance between two groups (1/95 vs. 3/98, p = 0.327). During follow-up at 6 months, no difference was exhibited by the two groups on frequent relapse rates ( p = 0.134). Conclusion: If a course of AZM is added to the glucocorticoid-induced treatment among children with PNS, then the sensitivity of prednisone increases. This increase consequently reduces duration to remission and decreases relapse. However, further studies are necessary to confirm these results. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this study was to investigate the appropriate measures for diagnosing and treating perineal endometriosis (PEM) with anal sphincter involvement. METHODS Between January 1992 and April 2011, the clinical features, diagnosis and management of 31 patients who were diagnosed with PEM with anal sphincter involvement at the Peking Union Medical College Hospital were retrospectively analyzed using their clinical records. A range of 6–78 months of outpatient follow-up after surgery were conducted for these 31 patients but was extended by telephone interviews with 29 patients conducted in December 2011. RESULTS All 31 patients had a history of vaginal delivery. The level of serum CA125 was elevated in only 2 (6.5%) cases. All cases received surgical treatment, which included narrow excision (NE, close to the edge of the endometrioma) with primary sphincteroplasty (PSp) for 30 cases and incomplete excision (IE) for 1 case. Of the 30 cases in the NE group, 20 (66.7%) received hormone therapy preoperatively. Up until December 2011, there was one recurrence (3.6%) of PEM in the NE group. PEM relapse occurred in the IE patient 6 years after the initial IE surgery. Perineal abscesses were found in one patient post-operatively. No complaint of dyspareunia and no fecal incontinence episodes were observed during follow-up. CONCLUSIONS Based on our own experience, NE and PSp may be indicated for the treatment of PEM with anal sphincter involvement. [ABSTRACT FROM PUBLISHER]

Objective: To investigate the clinical characteristics, treatment, and factors of recurrence of abdominal wall endometriomas (AWE).Method: Sixty-four cases of AWE diagnosed at Peking Union Medical College Hospital (PUMCH) from 1983 to 2003 were reviewed retrospectively.Result: There was an AWE incidence of 0.044% among the parturients undergoing cesarean section at PUMCH, of whom 87.5% had the typical complaint of an enlarging mass and pain during menstruation. Among these women, 62 underwent low abdominal surgery for endometrioma (2 for primary umbilicus endometrioma); 2 women with small endometriomas opted for a temporary medical solution and had relief after menopause. The latent period of AWE positively correlated to the women's age at onset of symptoms (P<0.001). Of the 62 women who underwent local excision, 19 had an unsatisfactory experience with medical management. There were 5 recurrences and 1 evolution to malignancy during a mean follow-up of 83.7 months. Recurrence was closely related to the size and depth of lesions.Conclusion: Because of its typical clinical manifestations, abdominal wall endometriomas could be diagnosed before pregnancy. Surgical excision is the only effective treatment and wide local excision with clear margins is the key point to prevent recurrence. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the expression and predictive value of serum hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in patients with burns following treatment. A total of 84 patients with burns treated in Jinan City People's Hospital (Jinan, China) between June 2015 and August 2017 were selected and their clinical information was collected. The expression levels of HIF-1α and VEGF before and after treatment were detected via ELISA, and HIF-1α and VEGF levels in patients with effective and ineffective treatment were compared. The predictive values of HIF-1α and VEGF in clinical efficacy were determined using receiver operating characteristic (ROC) curves, and independent risk factors affecting treatment inefficacy were analyzed via multivariate logistic regression. It was revealed that HIF-1α decreased significantly (P<0.05) while VEGF significantly increased in patients after treatment. Patients with effective treatment presented significantly lower HIF-1α levels and higher VEGF levels compared with those with ineffective treatment. The ROC curve indicated that the area under the curve (AUC) of HIF-1α for treatment efficacy was 0.795, the 95% CI was 0.666-0.924, the specificity and sensitivity were 68.75 and 80.88%, respectively, and the Youden index was 49.63%. For VEGF, the AUC, 95% CI, specificity, sensitivity and Youden index were 0.826, 0.725-0.928, 68.75, 82.35 and 51.10% respectively. Moreover, under the joint detection of HIF-1α and VEGF, the AUC was 0.847, 95% CI was 0.746-0.947, specificity and sensitivity were 87.50 and 66.18%, respectively, with a Youden index of 53.68%. Multivariate analysis demonstrated that higher HIF-1α level, lower VEGF level and higher burn degree before treatment were independent risk factors for treatment inefficacy. HIF-1α levels decreased and VEGF levels increased in burn patients after treatment. HIF-1α and VEGF before treatment may therefore serve as predictors for treatment efficacy. [ABSTRACT FROM AUTHOR]

Objective: To analyze the clinical presentation of perineal endometriosis and evaluate its treatment.Methods: Clinical data were analyzed from the records of 36 patients with perineal endometriosis who were operated on between 1983 and 2007 at Peking Union Medical College Hospital, and followed up for 0.5 to 14 years.Results: The incidence of perineal endometriosis was 0.31% among the women with endometriosis treated surgically at the hospital. The latent period was between 4 months and 13 years. All patients had cyclical and painful lesions. Of the 36 patients, 5 (13.9%) also suffered from pelvic endometriosis. All patients without anal sphincter involvement were cured after complete surgical excision. In 7 patients who had anal sphincter involvement, disease recurred because of incomplete excision.Conclusion: Perineal endometriosis can be diagnosed on the basis of clinical features and surgical excision is the treatment of choice. The recurrence rate of perineal endometriosis is related to sphincter involvement making preoperative evaluation of anal sphincter important. [ABSTRACT FROM AUTHOR]

Gas-lubricated microbearings are widely applied in multiple fields due to their advantages of high-speed, low friction level and other features. The operating environment of microbearings is complex, and the difference of temperature has an important influence on their comprehensive performance. In this investigation, FEM (finite element method) is employed to investigate the static, dynamic and limit characteristics of microbearings lubricated by different kinds of gas at different temperatures. The results show that the rise of temperature leads to the decline of equivalent viscosity of gas, which weakens the load capacity of microbearings, and furthermore, affects the operating stability of microbearings. The dynamic performances of microbearings at different temperatures are very different, and the two dynamic limit characteristics are more sensitive to temperature when it changes. [ABSTRACT FROM AUTHOR]