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Exercise intolerance is a major manifestation of pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD). We aimed to investigate the characteristics of exercise intolerance in different subgroups of PAH-CHD.We retrospectively enrolled 171 adult patients with PAH-CHD and 30 age and sex-matched healthy subjects and performed cardiopulmonary exercise testing. Gas exchange parameters, including peak oxygen uptake (peak V̇oThe median age of patients at enrollment was 27.8 years, and 131 (76.6%) were female. Peak V̇oExercise capacity was severely reduced in patients with PAH-CHD. Among the four subgroups, patients with Eisenmenger syndrome had the worst exercise capacity and ventilatory efficiency.

Because of the complex components, simple content determination can hardly reflect the overall quality of Guizhi Fuling Capsules. Therefore, it is necessary to carry out a multi-component dissolution test. The variability of quality among different batches of products from different manufacturers is a common problem of Chinese medicine solid preparations. To comprehensively control the quality of Guizhi Fuling Capsules, we studied the dissolution behaviors of 7 index components in the capsules under different conditions, and investigated the consistency of dissolution behaviors among different batches of products from the same manufacturer. The basket method of general rule 0931 in Chinese Pharmacopoeia was adopted, and the rotating speeds were set at 50, 75, and 100 r·min~(-1), respectively. The hydrochloric acid solution(pH 1.2), acetate buffer solution(pH 4.0), pure water, and phosphate buffer solution(pH 6.8) were used as the dissolution media. Automatic sampling was carried out at the time points of 5, 10, 20, 30, 45, and 60 min, respectively. The cumulative dissolution of 7 index components was measured through ultra-performance liquid chromatography(UPLC). The difference factor f_1 and similarity factor f_2 were calculated to comprehensively evaluate the similarity of the dissolution curves among 8 batches of Guizhi Fuling Capsules, and a variety of dissolution and release equations were fitted. The results showed that multiple components had faster dissolution rates at higher rotating speed and in hydrochloric acid medium. The 8 batches of Guizhi Fuling capsules showed the average f_1 value lower than 15 and the average f_2 value higher than 50, which indicated that different batches of products had similar dissolution behaviors. Most components had synchronous dissolution behaviors and similar release cha-racteristics. This study provides a reference for the quality consistency evaluation among batches, processing optimization, and dosage form improvement of Guizhi Fuling Capsules.

Doxorubicin (DOX) is an anthraquinone drug used for the efficient treatment of a variety of tumors in human beings. Unfortunately, its poor biodegradability causes incomplete metabolism in the body. Therefore, it is of great significance to synthesize a sensitive and selective material for DOX detection. In this paper, we report a water-soluble Tb

Beyond reasonable designing catalysts, the optimization of preparing air cathode has far-reaching implications for the development of Zinc-air batteries. In this study, the effect of Polytetrafluoroethylene (PTFE) in current collecting layer on the performance of Zinc-air battery was investigated. The results showed that as the polytetrafluoroethylene (PTFE) content and heat treatment temperature changed, the hydrophobicity and porosity of current collecting layer also changed, thereby affecting the performance of air cathode. The air cathode assembled with PTFE-3-300 possessed an excellent electrochemical performance, which was prepared by brushing PTFE and acetylene black (wherein the mass ratio of them is 18:5) on current collecting layer and then heating at 300 °C. The obtained air cathode displayed relatively small polarization loss and excellent rate performance, showing a polarization potential of - 0.405 V vs. Hg/HgO at 100 mA cm−2 and the voltage retention of 94.47% from 5 to 20 mA cm−2. Besides, the air cathode displayed excellent discharge stability maintaining average potential 1.3249 V for 100 h. Based on this work, a detailed understanding of the relationship of PTFE and current collecting layer can be achieved to improve the electrode design, architecture and fabrication.

In order to avoid the loss caused by sudden power failure or loss, UPS is very necessary.As the core part of UPS, the efficiency of DC-DC converter improvement has been a long-term research direction in the industry.Switch tube loss are the main factors influencing the DCDC converter efficiency, SI power component is affected by its material, its performance is difficult to further improve, seriously affect the efficiency of the DC-DC converter, SiC semiconductor with high band gap width, the advantages of high heat conductivity and high electric breakdown strength in recent years become a hot research direction at home and abroad, and silicon carbide material improves the device the possibility of high frequency, miniaturization and efficiency.Compared with Si power devices, the advantages of SiC power devices are higher voltage and temperature resistance, higher operating frequency and lower switching losses.

As the important device to perceive the operating state of grid, the condition monitoring device of electric equipment solves such problems as the high rate of false alarm and failure of device caused by the low temperature in winter of cold areas. This paper measures the thermal conductivity of such three kinds of materials as asbestos, rubber and nano porous aerogels in the temperature range of -55°C to +80°C by steady state method, and analyzes the influence of temperature on the thermal conductivity of three materials. According to the result of experiment, the thermal conductivity of nano porous aerogels is the lowest and is affected least by temperature among three kinds of materials. Nano porous aerogels apply to state monitoring device operated in cold areas; and rubber can also be used as thermal insulation material when the operating temperature is generally higher than -20°C.

Storage battery is an indispensable energy storage device at present. It is widely applied to industries like electric automobiles due to its advantages such as safety, reliability, low cost, etc. However, like most storage batteries, lead-acid battery has a series of problems in the low temperature environment such as the plunge of capacity, difficulty of charge, and so on, which deeply influence its application effect. To improve the low temperature performance of lead-acid battery, carbon materials could be added to the cathode of lead-acid battery. By measuring the properties like HRPSoC cycle and dynamic charging under different carbon (graphite) content, this article concludes that the addition of carbon material could improve the low-temperature performance of lead-acid battery. When the carbon content is between 0.3% and 0.9%, the improvement effect is relatively better. The research result of this article has a reference function to the design and development of low-temperature lead-acid batteries.

Epoxy resin insulating materials have been extensively applied to main power transmission and transformation equipment. As the use environment of power transmission and transformation equipment becomes increasingly harsh, the reliability requirement of power grids for equipment is becoming higher and higher. It’s very necessary to master electrical and mechanical properties of low-temperature epoxy resin insulating materials. Dielectric properties, power-frequency breakdown properties, power-frequency flashover properties and mechanical properties of epoxy resin insulating materials under low temperature were investigated in this paper. The study results indicate that as the temperature declines, dielectric properties of epoxy resin composite materials are slightly degraded. After the temperature drops to below -40°C, dielectric properties start being gradually recovered to the state under normal temperature; AC breakdown, AC flashover and tensile properties of the materials are gradually improved as the temperature decreases.

The catalyst in the oxygen electrode is the core component of the aqueous metal-air battery, which plays a vital role in the determination of the open circuit potential, energy density, and cycle life of the battery. For rechargeable aqueous metal-air batteries, the catalyst should have both good oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic performance. Compared with precious metal catalysts, non-precious metal materials have more advantages in terms of abundant resource reserves and low prices. Over the past few years, great efforts have been made in the development of non-precious metal bifunctional catalysts. This review selectively evaluates the advantages, disadvantages and development status of recent advanced materials including pure carbon materials, carbon-based metal materials and carbon-free materials as bifunctional oxygen catalysts. Preliminary improvement strategies are formulated to make up for the deficiency of each material. The development prospects and challenges facing bifunctional catalysts in the future are also discussed.

Background: A variety of supraventricular arrhythmias (SVAs) may occur in patients with hypertrophic cardiomyopathy (HCM). The characteristics and long-term ablation outcomes of different types of SVAs in HCM have not been comprehensively investigated.Methods: We retrospectively enrolled 101 consecutive patients with HCM who were referred to the electrophysiology and arrhythmia service from May 2010 to October 2020. The clinical features and ablation outcomes were analyzed.Results: Seventy-eight patients had SVAs, which comprised 50 (64.1%) cases of atrial fibrillation (AF), 16 (20.5%) of atrial flutter (AFL), 15 (19.2%) of atrioventricular reentrant tachycardia (AVRT), 11 (14.1%) of atrial arrhythmia (AT), and 3 (3.8%) of atrioventricular nodal reentrant tachycardia (AVNRT). Thirty-four patients underwent catheter ablation and were followed up for a median (interquartile range) of 58.5 (82.9) months. There was no recurrence in patients with non-AF SVAs. In patients with AF, the 1- and 7-year AF-free survival rates were 87.5 and 49.5%, respectively. A receiver operator characteristic analysis showed that a greater left ventricular end-diastolic dimension (LVEDD) was associated with a higher recurrence of AF, with an optimum cutoff value of 47 mm (c-statistic = 0.91, p = 0.011, sensitivity = 1.00, specificity = 0.82). In Kaplan–Meier analysis, patients with a LVEDD ≥ 47 mm had worse AF-free survival than those with a LVEDD p = 0.014).Conclusions: In this unique population of HCM, AF was the most common SVA, followed in order by AFL, AVRT, AT, and AVNRT. The long-term catheter ablation outcome for non-AF SVAs in HCM is satisfactory. A greater LVEDD predicts AF recurrence after catheter ablation in patients with HCM.

Background: Right ventricle (RV) function is among the most important prognostic factors for pulmonary arterial hypertension (PAH) patients. Inhaled iloprost, an inhaled member of the prostacyclin family, is effective for the treatment of severe PAH and acute RV failure. However, the acute effects of iloprost on RV physiology have not been thoroughly explored in the past.Materials and Methods: This prospective study involved 69 incident PAH patients, including 23 idiopathic PAH (IPAH) patients, 26 patients with PAH associated with connective tissue disease (CTD-PAH) and 20 with PAH associated with congenital heart disease (CHD-PAH). All patients underwent both right heart catheterization and cardiac magnetic resonance imaging at baseline and 20 min after 5 μg iloprost inhalation.Results: Acute iloprost inhalation reduced PVR from 13 ± 7 to 10 ± 6 Wood U (P < 0.001), increased RV ejection fraction (RVEF) from 31 ± 11 to 35 ± 12 % (P < 0.001), increased RV stroke volume from 53 ± 21 to 57 ± 22 ml (P < 0.001) and decreased RV end-diastolic volume from 179 ± 67 to 172 ± 69 ml (P < 0.001). Acute iloprost inhalation-induced RVEF improvement was correlated with the degree of PVR reduction (P < 0.001) in IPAH patients, but not in CTD-PAH or CHD-PAH patients.Conclusion: Acute iloprost inhalation improved RVEF, RV stroke volume and decreased RV volume in IPAH and CTD-PAH patients. Iloprost-induced RVEF increase was proportional to PVR reduction in IPAH patients, but not in CTD-PAH or CHD-PAH patients.

Although infant formula represents an important human milk substitute, it has been shown to contain many different lipid structures compared to human milk. In this study, the lipidome and fatty acid composition of human, bovine and caprine milk were analyzed and compared. A total of 13 lipid classes (including TG, DG, SM, PC, Cer, HexCer, Hex2Cer, PE, PG, PS, PI, PA and CL) were analyzed. Human milk was richer in TG containing LA, SM containing ULCFA and PLs containing ARA, DHA and DGLA. Moreover, there were no differential DG and SM species between human and caprine milk. A total of 215 and 147 lipids were identified as potential biomarkers that could be used to further analyze differences in the biological properties of human, bovine and caprine milk. This comprehensive analysis will hopefully help in the design of infant formula more suitable for Chinese babies.

A study is made about the structure and its mathematical model of FT-PMM. The design of the vector control system (SVPWM) based on the id = 0 control strategy is proposed, which realizes the closed-loop vector control with feedback of speed, current, and position. This method is proved right by Matlab simulation. From a hardware level, the dsPIC30f4011 is used as the core of the system. With the help of the design of the bootstrap power supply of IR2110, the number of power is reduced and the cost is saved. The inverter circuit consists of 3 independent H bridges was used to control each wingding independently in order to enhance the ability of fault tolerance. Through hardware test, the result indicates that this vector control system could satisfy the demands of speed control and stable operation. After Man-made fault is set, the fault-tolerant performance is analyzed and the system is proved to have fault-tolerant capability to a certain extent.

Quasi-homogeneous lean mixture combustion technology can take full advantages of lean-combustion, and help reduce the engine fuel consumption and emissions. Quasi-Homogeneous Lean-burn engine Control System, combined virtual instruments with engine electronic control technology, can precisely control air-fuel ratio injection, timing, fuel injection pulse and ignite on timing, which provides a reliable and convenient platform for the engine lean-burning performance tests..

This paper describes a new navigational algorithm that combines Artificial Potential Fields with PID controller to realize accurate channel survey, automatic obstacle avoiding, optimal route search et al. A set course can be obtained through this new algorithm and the steering of the unmanned survey ship will be worked out by closed-loop control. In test system, the location of the ship is obtained by GPS, and the error of electric steering gear angle controls PWM pulse signal, which drives servo motor by power amplifying device, thus making the electric steering gear to turn as expected. Communication between upper and lower computer is realized by C language and serial port communication, so as to get parameter information and track images of the ship in a real-time manner. The result shows that the new navigational algorithm more efficient and precise, and can be widely used in fairway surveying engineering.

Steel fiber concrete is a new-type composite material of excellent property with broad application formed by common concrete mixed with disorderly oriented short steel fiber. Main action of steel fiber is to prevent broadening of interior micro crack in concrete and restrict occurrence and growth of macro crack. Based on basic theory of concrete fracture mechanics, this treatise adopts four-point shearing sampling material to conduct experimental research, having obtained critical fracture curve of crack of composite mode I, II of steel fiber concrete, setting up experimental formula of fracture criterion, probing into difference between fracture toughness of steel fiber concrete and that of common concrete, and discussing application of maximum tension stress theory in steel fiber concrete.

Intact nitric oxide (NO) signalling is critical to maintaining appropriate pulmonary vascular tone. NO bioavailability is reduced in patients with pulmonary arterial hypertension. This study aimed to examine the impact of NO plasma metabolites (NOx) relative to haemodynamic dysfunction and mortality in patients with idiopathic pulmonary arterial hypertension (IPAH).A total of 104 consecutive adult IPAH patients who had undergone genetic counselling when first diagnosed were enrolled in this prospective study.The median concentration of NOx (μmol·L−1) was significantly lower in IPAH patients compared with healthy subjects, and was decreased further in 19 carriers of the bone morphogenetic protein-receptor type-2 (BMPR2) mutation compared to non-carriers. Reduced concentrations of NOx were correlated with mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR) and cardiac output. Compared with higher baseline NOx concentrations, patients with a NOx concentration of ≤10 μmol·L−1 had a markedly worse survival. After adjustment for clinical features, a BMPR2 mutation and haemodynamics, a lower NOx level remained an increased risk of mortality.Patients with IPAH had lower levels of plasma NOx, which correlated inversely with mPAP, PVR and survival. Plasma NOx may be an important biomarker and prognostic indicator, suggesting that reduced NO synthesis contributes to the pathogenesis of IPAH.

The low modulus of elasticity of the FRP bars and their non-yielding characteristics results in large deflection and wide cracks in concrete beams reinforced with FRP bars. Consequently, in many cases, serviceability requirements may govern the design of such members. Based on the experiment studies of 5 beams of 2 groups under vertical loads at three-dividing point, the characteristics of FRP reinforced concrete beams was researched. At the same time, the experimental beams are modeled and the influencing factors of deflection of FRP bars concrete beam are analyzed using ANSYS program.

Many targeted therapies have been approved for pulmonary arterial hypertension (PAH), most of which are in oral forms. However, the effects of these drugs on lifesaving are unclear. Our objective was to evaluate the effects of oral treatments on clinical outcomes especially all-cause mortality in patients with PAH.MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for relevant articles up to April 2014. Randomized, double-blind, parallel-group clinical trials that compared oral agents with placebo were selected. Data for populations, interventions, and outcomes were extracted independently by 2 investigators, and disagreements were resolved by consensus. Quality assessment was performed using the Cochrane risk-of-bias tool.Twenty-one randomized, controlled, clinical trials involving 5105 patients were identified in the primary analysis. The overall estimated odds ratio (OR) of combined clinical worsening (CCW) events between active treatment groups and control groups was 0.55 (95% CI 0.47-0.64, P.001). However, the effect of oral treatments on reducing all-cause mortality was not statistically significant (OR 0.82, 95% CI 0.61-1.10, P = .192), which was consistent for approved drugs (OR 0.84, 95% CI 0.61-1.18, P = .316) and drugs that were not approved (OR 0.72, 95% CI 0.36-1.44, P = .352). In the sensitivity analysis, a significant reduction was achieved in CCW events (P.001) but not in all-cause mortality (P = .057).This pooled analysis shows the benefits of oral treatments on CCW events in patients with PAH. However, these drugs seem to exhibit less favorable effects on life expectancy in the short-term follow-up, suggesting further evaluation is required.

Pulmonary arterial hypertension (PAH) can cause morbidity and mortality in children. Although adult and pediatric PAH share many similarities, many differences have been found in children. Thus, a new classification for pediatric pulmonary hypertensive vascular disease has been proposed. Both child and adult gene mutation carriers with PAH tend to have worse prognoses. Pediatric patients present with better preserved functional class, and parents should pay high attention to any children with unexplained shortness of breath, fatigue or syncope, as symptoms of PAH in children are often misleading. Right heart catheterization is necessary for diagnosis. Although there are few medications approved for pediatric PAH and evidence-based treatment algorithms for children are still lacking, the survival of pediatric patients has been improved significantly since targeted therapies approved for adults were introduced to pediatric patients. PAH in children is unique, and further studies are needed to have a better understanding of it.

OBJECTIVE To study the chemical constituents and activity of total flavonoids contained in Yushen Tang,in order to lay a foundation for defining active consituents of the prescription and their mechanism. METHOD The activity of total flavonoids contained in Yushen Tang were evaluated by in vitro H2O2-induced human umbilical vein endothelial cell injury experiment. The chemical constituents were separated and purified by such methods as silica column chromatography, macroporous resin chromatography, sephadex and HPLC preparation,and their structures were identified on the basis of their spectral data and physicochemical properties. RESULT Total flavonoids contained in Yushen Tang showed the effects in inhibiting hydrogen peroxide-induced human umbilical vein endothelial cell (HUVEC) injury and down-regulating PAI-1 expression (P

To improve the training speed of SVM, we propose a new SVM training approach which takes thick convex-hull as training set. The approach makes better use of the margin information for classification of data sets, and thus extends the use of convex hull to approximately linearly separable problems. Experiments on 5 UCI data sets indicate that the approach speeds up training of SVM with guarantee of generalization accuracy.