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Wind-tunnel tests of the double-swept waverider were performed in the off-design states, aiming to analyze its potential advantage in wide-speed performances. The test configurations were generated using the planform-customized waverider design, developed from the osculating-cone method. Then models of double-swept waveriders with the bend and cusp head were fabricated, and compared with a model of a single-swept waverider also built using the same method. A variety of experiments in their on-design and off-design states were performed in the hypersonic wind tunnel FD-07 of our institute, and computational fluid dynamics were employed to simulate flowfields as a supplement. According to the wind-tunnel tests and flow simulations, the aerodynamic forces and longitudinal stability were obtained and analyzed. The aerodynamic performance of the double-swept waverider did not fall significantly when deviating from the design states. The general trend was that, as Mach number increased, the lift-to-drag ratios dropped slightly. The double-swept waverider featured large longitudinal stability margin in hypersonic states, and the change in Mach number had little effect on longitudinal stability. Compared with the single configuration, the double-swept waverider suffered a decrease in lift-to-drag ratio, but showed a significant improvement in longitudinal stability.

A 37-year-old male patient with corrected transposition of great arteries (ccTGA) with cor triatriatum sinister (CTS), left superior vena cava, and atrial septal defects is reported in our case. None of these impacted the patient's growth or development, nor daily work until age 33. Later, the patient developed symptoms of obvious impaired heart function, which improved after medical treatment. However, the symptoms reappeared and gradually worsened two years later, and we decided to treat it with surgery. In this case, we selected tricuspid mechanical valve replacement, cor triatriatum correction, and atrial septal defect repair. During the follow-up of five years, the patient had no obvious symptoms, ECG did not change significantly from five years ago, and the cardiac color Doppler ultrasound showed RVEF 0.51.

Waveriders are of high lift-to-drag (L/D) ratio in hypersonic states; however, low volume of loading limits its application in practical engineering significantly. Raising the upper surface is a method to increase the volume space for waveriders, and this article studies the effect of the upper surface shape on the aerodynamic performances based on a single swept waverider configuration. Cubic polynomials were employed to construct the upper surface to replace the freestream-traced surface, and 2 parameters, the trailing edge thickness and inclination angle of head, were extracted as design variables. Analyzing the flow field using computational fluid dynamics techniques, raising the upper surface only had effect on the aerodynamic performance from the upper surface, but nearly no effect on the lower surface, and thus the design of upper and lower surfaces can be decoupled. As the trailing edge thickness and inclination angle of head increase, the volume of waveriders grows rapidly, while the loss in L/D ratio is limited. Compared with expanding the lower surface, raising the upper surface yielded better aerodynamic performances. The results indicate that raising the upper surface is a feasible and efficient approach to increase the loading volume of the waverider and hence promote its application in engineering.

BackgroundCardiac foreign bodies are extremely rare in clinical patients, especially when foreign bodies damage the internal structure of the heart coincidentally after they penetrate the heart.Case presentationHere, we report the case of a two-year-old girl whose heart was penetrated by a needle, which triggered mitral valve regurgitation and endocarditis. After a comprehensive inspection, accurate judgment and surgical preparation, we removed the needle and repaired her mitral valve. Fortunately, she recovered postoperatively.ConclusionFrom this case, we can know that when cardiac foreign bodies are suspected, ultrasound is an important inspection method. Moreover, the approaches for handling each such case are different depending on the associated injuries.

Purpose Pulmonary arterial hypertension (PAH) is a formidable disease with no effective treatment at present. With the goal of developing potential therapies, we attempted to determine whether ethyl pyruvate (EP) could alleviate PAH and its mechanism. Methods Pulmonary smooth muscle cells were cultured in conventional low-oxygen environments, and cellular proliferation was monitored after treatment with either EP or phosphate-balanced solution (PBS). Expression of high mobility group protein B1 (HMGB1) and receptor for advanced glycation end-products (RAGE) protein were detected by western blot. After hyperkinetic PAH rat models were treated with EP, hemodynamic data were collected. Right ventricular hypertrophy and pulmonary vascular remodeling were evaluated. Expression of HMGB1 and RAGE protein was also detected. Results In vitro, proliferative activity increased in low-oxygen environments, but was inhibited by EP treatment. Furthermore, Western blotting showed the decreased expression of HMGB1 and RAGE protein after EP treatment. In vivo, pulmonary artery pressures were attenuated with EP. Right ventricular hypertrophy and pulmonary vascular remodeling were also reversed. Additionally, the expression levels of HMGB1 and RAGE were reduced in lung tissues. Conclusions EP can alleviate PAH by suppressing the proliferation of pulmonary artery smooth muscle cells via inhibition of HMGB1/RAGE expression.

Myocardial infarction (MI) is one of the major causes of death worldwide, and the therapeutic strategies of MI are still limited. In this study, we investigated the function of miR-665 in MI. In the present study, an ischemia/reperfusion (I/R) rat model and a hypoxia/reoxygenation (H/R)-induced H9c2 cell model were successfully established to mimic the MI for in vivo and in vitro studies. The concentrations of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), tumor necrosis factor alpha (TNF-α), IL-6, and reactive oxygen species (ROS) were then measured. Moreover, cell viability and apoptosis were detected by MTT assay, TdT-mediated dUTP nick end labeling (TUNEL), and PI/FITC-annexin V assay. The binding of miR-665 and Pak1 was determined by luciferase assay. miR-665 was upregulated in I/R rats, and the overexpression of miR-665 significantly increased LDH, CK-MB, TNF-α, IL-6, and ROS concentrations and induced cell apoptosis, while knockdown of miR-665 had opposite results. Consistent with in vivo results, miR-665 induced cell apoptosis and ROS generation in H/R-treated H9c2 cells. More importantly, Pak1 was the target gene of miR-665, and knockdown of miR-665 depressed the accumulation of ROS and cell apoptosis by targeting Pak1 and promoting the phosphorylation of Akt, whereas knockdown of Pak1 could attenuate the protection of miR-665 inhibitor in H/R-treated H9c2 cells. Therefore, knockdown of miR-665 protects against cardiomyocyte ischemia/reperfusion injury-induced ROS accumulation and apoptosis through activating Pak1/Akt signaling in MI. In general, understanding the biology and modulation of miR-665 may have the potential to counteract the development of MI.

Background: Double blood supply to the anterior descending artery is a rare finding of coronary angiography. However, infective endocarditis (IE) combined with anomalous double blood supply to the anterior descending artery has not been reported. Case presentation: A 58-year-old male previously diagnosed with IE came to the emergency department with complaints of chest tightness and dyspnea. Further examination confirmed severe aortic valve regurgitation combined with IE and anomalous double blood supply to the anterior descending artery. The cardiopulmonary bypass surgery was performed by direct perfusion through the normal left and right coronary openings. After surgery, the heart started beating again normally without any cardiogenic ischemic events. Conclusion: Cardiopulmonary bypass by direct perfusion was safe in the patient with anomalous double blood supply to the anterior descending artery.

Pulmonary arterial hypertension (PAH) is an extremely malignant cardiovascular disease which mainly involves the uncontrollable proliferation of the pulmonary arterial smooth muscular cells (PASMCs). Recent studies have confirmed that mitochondria play an important role in the pathogenesis of pulmonary hypertension through sensing cell hypoxia, energy metabolism conversion, and apoptosis. As a mitochondrial membrane protein, TUFM has been regarded to be related to mitochondrial autophagy (mitophagy), apoptosis, and oxidative stress. Considering these factors are closely associated with the pathogenesis of PAH, we hypothesize that TUFM might play a role in the development of PAH. Our preliminary examination has showed TUFM mainly expressed in the PASMCs, and the subsequent test indicated an increased TUFM expression in the SMCs of pulmonary arteriole in monocrotaline- (MCT-) induced PAH rat model compared with the normal rat. The TUFM knockdown (Sh-TUFM) or overexpressed (OE-TUFM) rats were used to establish PAH by treating with MCT. A notable lower pulmonary arterial systolic pressure together with slightly morphological changes of pulmonary arteriole was observed in the Sh-TUFM group compared with the single MCT-induced PAH group. Increased levels of P62 and Bax and reduced LC3II/I, BECN1, and Bcl2 were detected in the Sh-TUFM group, while the expressions of these proteins in the OE-TUFM group were contrast to the results of the Sh-TUFM group. To elucidate the possible mechanism underlying biological effect of TUFM in PAH, PASMCs were treated with silence or overexpression of TUFM and then exposed to hypoxia condition. An obviously high levels of P62 and Bax along with a decreased LC3 II/I, BECN1, ULK1, Atg12, Atg13, and Bcl2 levels were noticed in cells with silence of TUFM. Moreover, the phosphorylated AMPK and mTOR which was well known in mitophagy modulating vary by the alternation of TUFM. These observations suggested that TUFM silence inhibits the development of MCT-induced PAH via AMPK/mTOR pathway.

BackgroundHypertrophic cardiomyopathy (HCM) is the monogenic inherited cardiovascular disorder. In addition, single coronary artery (SCA) is a rare congenital anomaly of the coronary arteries. However, single coronary artery concomitant with severe obstructive hypertrophic cardiomyopathy has never been reported in the literature.Case presentationHerein, we present a 64-year-old female diagnosed as a single left coronary artery with severe obstructive hypertrophic cardiomyopathy. Obstructive hypertrophic cardiomyopathy was treated with "MORROW procedure". The patient was discharged on the seventh postoperative day and has been asymptomatic during the follow-up. ConclusionTo our knowledge, single left coronary artery with severe obstructive hypertrophic cardiomyopathy is the first to be reported in the literature. In addition, myocarial pretection by cardioplegia antegrade perfusion in the single coronary artery was safe in the patient with single coronary artery and obstructive hypertrophic cardiomyopathy.

The double swept waverider is a classic example of the planform-customized osculating-cone waveriders, delivering satisfactory performances over a wide range of velocities. The nonlinear increase i...

The global geometric relationship among the inlet capture curve, flow capture tube and planform contour line in the osculating-cone waverider design is deduced by a differential equation set. Planform-customized waverider is enabled to be constructed based on the geometric relationship. Thus the configuration with satisfactory wide-velocity-range performance is proposed, employing vortex effect to improve subsonic performance and shock effect to improve super/hypersonic performance, respectively. To validate the concept, the double swept waveriders are generated as test cases. Compared with flat plate models, the aerodynamic performance and flow mechanics of the double swept waverider are analyzed under subsonic and hypersonic conditions using computational fluid dynamics (CFD) simulation. CFD results show that the performance of the waverider with reasonable planform is favorable under both subsonic and hypersonic conditions, remedying some deficiencies of traditional waverider. The work demonstrates a new thought for wide-velocity-range configuration design.

Poly (propylene carbonate, PPC) is a new member of the aliphatic polyester family. An outstanding feature of PPC is that it produces mainly water and carbon dioxide when degraded in vivo, causing minimal side effects. This unique property together with excellent biocompatibility and biodegradability makes PPC a promising material for drug delivery. In this study, we explored the effect of the sirolimus (an inhibitor of cell growth)-eluting PPC mesh on graft stenosis and its possible mechanisms in a rat arteriovenous grafting model. The PPC mesh was prepared by electrospinning. A jugular vein to abdominal aortic autograft transplantation model was established in rats. The graft was then treated by wrapping with the drug mesh or the drug-free mesh or left untreated. Four weeks posttransplantation, neointima was measured with hematoxylin and eosin staining, matrix metalloproteinase-2 (MMP-2), and MMP-9, and proliferating cell nuclear antigen (PCNA) in the grafts were assayed by Western blotting and immunohistochemistry, respectively. In vitro rat aortic adventitial fibroblast cell (RAAFC) migration was assessed using the Boyden chamber assay, and phospho-mammalian target of rapamycin (mTOR) levels in RAAFCs were determined by Western blotting. Animals with the drug mesh had an intimal area index of 4.87% ± 0.98%, significantly lower than that of the blank group (14.21% ± 2.56%) or the PPC group (15.03% ± 2.35%, both P < .05). The sirolimus mesh markedly suppressed MMP-2 and MMP-9 expression, decreased PCNA-positive cell numbers, inhibited RAAFC migration, and reduced phospho-mTOR levels. Our data suggest that the sirolimus-eluting PPC mesh might be potentially applied for the management of grafting stenosis.

Objective To study the risk factors of oxygenation impairment in patients with type-A acute aortic dissection who underwent total arch replacement with a stented elephant trunk. Methods In this study, 169 consecutive patients were enrolled who were diagnosed with type-A acute aortic dissection and underwent a total arch replacement procedure at the Qilu Hospital of Shandong University between January 2015 and February 2017. Postoperative oxygenation impairment was defined as arterial oxygen partial pressure/inspired oxygen fraction ≤ 200 with positive end expiratory pressure ≥ 5 cm H2O that occurred within 72 hours of surgery. Perioperative clinical characteristics of all patients were collected and univariable analyses were performed. Risk factors associated with oxygenation impairment identified by univariable analyses were included in the multivariable regression analysis. Results The incidence of postoperative oxygenation impairment was 48.5%. Postoperative oxygenation impairment was associated with prolonged mechanical ventilation time, intensive care unit stay, and hospital stay. Multivariable regression analysis demonstrated that body mass index (odds ratio [OR], 1.204; 95% confidence interval [CI], 1.065-1.361; P = .003), preoperative oxygenation impairment (OR, 9.768; 95% CI, 4.159-22.941; P Conclusions Postoperative oxygenation impairment is a common complication of surgery for type-A acute aortic dissection. Body mass index, preoperative oxygenation impairment, preoperative homocysteine, circulatory arrest time, and plasma transfusion were independent risk factors for oxygenation impairment after a total arch replacement procedure.

In this work, a novel airframe/propulsion integration design method of the wing-body configuration for hypersonic cruise aircraft is proposed, where the configuration is integrated with inward-turning inlets. With the help of this method, the major design concern of balancing the aerodynamic performance against the requirements for efficient propulsion can be well addressed. A novel geometric parametrically modelling method based on a combination of patched class and shape transition (CST) and COONs surface is proposed to represent the configuration, especially a complex configuration with an irregular inlet lip shape. The modelling method enlarges the design space of components on the premise of guaranteeing the configuration integrity via special constraints imposed on the interface across adjacent surfaces. A basic flow inside a cone shaped by a dual-inflection-point generatrix is optimized to generate the inward-turning inlet with improvements of both compression efficiency and flow uniformity. The performance improvement mechanism of this basic flow is the compression velocity variation induced by the variation of the generatrix slope along the flow path. At the design point, numerical simulation results show that the lift-to-drag ratio of the configuration is as high as 5.2 and the inlet works well with a high level of compression efficiency and flow uniformity. The design result also has a good performance on off-design conditions. The achievement of all the design targets turns out that the integration design method proposed in this paper is efficient and practical.

Applying a parameterization technique with fewer parameters and high fidelity improves the efficiency and accuracy of aerodynamic shape optimization. The class and shape transformation (CST) method is concise and efficient. Nevertheless, it is difficult to parameterize complex vehicle configurations using a unified CST method. This article presents a multi-block CST method after analyzing the mathematical description of the method, and this method joins adjacent surfaces smoothly and retains the good properties of the CST method. Modeling cases indicate that the multi-block CST method can reduce the number of design variables used to represent surfaces with uneven curvature distributions and can smoothly model various classes of surfaces. A system of aerodynamic shape optimization is developed based on the multi-block CST method, Pareto genetic algorithms and hypersonic aerodynamic engineering analysis, and the aerodynamic characteristics of a quasi-waverider wing-body vehicle are improved significantly after optimization. A novel configuration is also created using the optimization system. The optimization results indicate that the multi-block CST method, which involves fewer design variables and yields higher fidelity, is a powerful tool for aerodynamic shape optimization.

In the customized-planform waverider derived from the osculating-cone method, when the design curve Inlet Capture Curve (ICC) is selected or determined, its curvature distribution is possibly irregular, leading to a failure of waverider generation. Moreover, in the osculating-cone method, the curvature distribution of ICC is required to be continuous, restricting the design space significantly. In this paper, the effect of modifying and altering the curvature distribution of ICC on the customized-planform waverider is investigated. Test configurations with different curvature distributions of ICC are generated in the two types of customized-planform waveriders and their aerodynamic performances are calculated using CFD techniques. The results indicate that altering the curvature distribution does not break the ‘wave-riding’ performance of high lift-to-drag ratio for the customized-planform waverider significantly. Therefore, in the customized-planform waverider, infeasible curvature distribution of ICC can be modified locally to make the waverider generation work. Meanwhile, altering the curvature distribution of ICC provides an approach to increase the volume of a waverider. Moreover, in the osculating-cone waverider, the ICC curve can be selected over a wider range, even including the curves with non-continuous second-order derivatives, enlarging its design space dramatically.

Global geometrical relationships are proposed between the design parameters and configuration parameters of the osculating-cone method. A kind of double swept waverider is discussed primari...

The pier column backfilling method in the goaf of a thin coal seam introduced in this paper is the latest backfilling technology in China, which has the combined advantages of high efficiency and low cost. In order to fully verify the load bearing effect of this backfilling method, a comprehensive evaluation model which combined the actual measurement, numerical simulation and physical simulation is implemented in this paper. First, the stress bearing formula and backfilling volume rate of a pier column backfilling body is obtained by theory analysis. Then, through field monitoring, it was concluded that the bearing capacity when the backfilling body reached a stable state was similar to the results of theoretical calculation, and no obvious deformation occurred by observation the roadway deformation with the site. Finally, based on the drilling columnar and lithological parameters of the site, corresponding physical and numerical models were established and used to study the bearing effect of this backfilling method. It could be found that the stresses and displacements data that resulted from the simulation relatively confirmed data obtained from the site. After comprehension of above researches, it is concluded that the pier column backfilling method in a goaf has good bearing effect and a good economic benefit for mining thin coal seams.

ObjectivesWe sought to explore and create a reliable, convenient, and economic hyperkinetic pulmonary artery hypertension (PAH) model and confirm the exact time of establishing a reversible or irreversible model to serve as a platform for future studies.MethodsWe used a common carotid artery and jugular vein shunt with an anastomosis and cuff to create a hyperkinetic PAH model in rabbits. At 1, 2, 3, 6, and 12 months postoperatively, the systolic pressure, mean pulmonary arterial pressure, and mean arterial pressure were measured by catheterization and the right ventricle hypertrophy index was calculated. Pathologic changes in the small pulmonary arteries were observed with hematoxylin and eosin staining, and the Heath-Edwards classification system was used to evaluate PAH.ResultsThe anastomosis and cuff graft groups both increased in systolic pressure, mean pulmonary arterial pressure (P

BACKGROUND Ethyl pyruvate (EP) is an anti-inflammatory and anti-oxidant agent associated with many diseases. In this study, we evaluated whether EP could attenuate monocrotaline-induced pulmonary arterial hypertension (PAH). METHODS A PAH model was established by subcutaneously injecting a single dose of monocrotaline (60 mg/kg). And then a daily intraperitoneal injection of EP (50 mg/kg) was administered on day 1 to day 28 (preventive EP treatment) or day 15 to day 28 (therapeutic EP treatment). Hemodynamic changes were measured by catheterization, and the right ventricle hypertrophy index, the medial wall thickness, and the medial wall areas were also calculated. Enzyme-linked immunosorbent assay and immunohistochemical analysis were used to determine the serum levels and expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and endothelin-1 (ET-1) in the lung tissue. RESULTS Both preventive and therapeutic EP treatment significantly ameliorated hemodynamic changes and vascular remodeling indicators (all P < 0.05). The serum levels and expression of TNF-α, IL-6, and ET-1 in the lung tissue were also significantly decreased (all P < 0.05). CONCLUSIONS EP ameliorates monocrotaline-induced PAH and reverses pulmonary vascular remolding in rats by inhibiting the release of TNF-α and IL-6 and reducing the expression of ET-1.

The interaction between an anionic conjugated polyelectrolyte, poly[9,9-bis(3′-butyrate)fluoren-2,7-yl] sodium (BBS-PF), and bovine serum albumin was investigated by fluorescence spectroscopy. The emission of BBS-PF was effectively quenched by BSA with a quenching constant K SV of 3.1 × 107 L/mol when BSA was at nanomolar concentrations, but the emission increased when the concentration of BSA was at micromolar level. The excitation band of BBS-PF blue-shifted when the emission was quenched where the negatively charged BSA induced the aggregation of BBS-PF, yet the excitation band of BBS-PF red-shifted when the emission increased where the BSA acted as a surfactant and formed hydrophobic interaction with BBS-PF. BBS-PF could also quench BSA through energy transfer by resonance with a quenching constant K SV of 1.1 × 106 L/mol. The emission band changes of BSA reflected the conformation transitions of BSA from class II to class I and the binding of BBS-PF with BSA made the BSA more folded.

A series of high molecular weight, readily soluble copolymers of 9,9-dioctylfluorene with pyridine (less than or equal to 50 mol%) are synthesized by Suzuki polycondensation. Copolymers emit blue light and exhibit high PL efficiency. PL efficiencies show the maximum at 3,5-pyridine content of around 30 mol% in the copolymer. With further the increase of meta-linkage contents, PL efficiencies decrease rapidly to15% for alternating copolymer. Cyclic voltammetry investigation reveals that LUMO levels of copolymers increase with the increase of pyridine content. The introduction of pyridine unit at 3,5-position into polyfluorene backbone significantly depresses the excimer formation. The intensity of excimer emission decreases with the increase of 3,5-pyridine contents. Narrow and pure blue EL emission is obtained for copolymer with pyridine content of 40 mol%. External quantum efficiency is moderately high (0.4–0.5%) for such a pure blue emitter. The threshold voltages of devices from copolymers with the pyridine content of less than 40 mol% are low in the range of 5–6 V based on the device configuration: ITO/PEDOT/polymer/Ba/Al. The results indicate that fluorene-co-3,5-pyridine copolymers are promising blue-emitting electroluminescent materials.

Novel linear and tri-branched copolymers with triphenylamine and cyano groups in the main chain were synthesized by a concise route and an environment-friendly procedure without metal catalyst. They show strong fluorescence in solid state and can be used as non-doping emitter to fabricate emitting diodes. The single-layer electroluminescence devices with PVK or PEDOT buffer layer have been made with these copolymers as non-doping red–orange emitter, electron-transporting as well as hole-transporting material. The single-layer devices show preliminary results with maximum efficiency of 0.052% and EL wavelengths around 614 nm.

Background Hyperkinetic pulmonary arterial hypertension (PAH) is a common complication in congenital heart disease, and affects operations, indications, and prognoses for patients. Gene-based stem cell transplantation is an alternative treatment that can attenuate PAH. Methods Hyperkinetic PAH rabbit models were successfully established, using common carotid artery and jugular vein anastomosis. Endothelial progenitor cells (EPCs) were isolated from the bone marrow, cultured, and transfected with human hypoxia inducible factor-1 alpha (hHIF-1α), using lentiviruses. Two weeks after the transfected EPCs were transplanted into the rabbits, catheterization was applied to collect hemodynamic data. The hypertrophy of the right ventricle and pulmonary vascular remodeling were evaluated by measuring the right ventricle hypertrophy index, the medial wall thickness, and the medial wall area. Western blot and immunohistochemistry analyses were used to detect the expression of hHIF-1α in the pulmonary small arteries. Results Two weeks after transplantation, systolic pulmonary arterial pressure and mean pulmonary arterial pressure were both attenuated. The hypertrophy of the right ventricle, and pulmonary vascular remodeling were reversed. Expression of hHIF-1α in the hHIF-1α–transfected EPCs that had been transplanted was high, and the number of pulmonary small arteries had increased. In addition, combined HIF-1α and homogeneous EPC therapy was more effective at attenuating PAH and increasing the density of pulmonary small arteries, compared with EPC transplantation alone. Conclusions Both the therapy with HIF-1α–transfected EPCs, and EPC transplantation, attenuated shunt flow–induced PAH, by means of an angiogenic effect. The former therapeutic method was more effective.

Several new iridium complexes with p-substituted 2-phenylpyridine (R-PPy) ligands have been synthesized and characterized. The complexes were incorporated into phosphorescent polymer light-emitting devices using soluble poly[1,4-bis(6′-cyano-6′-methylheptyloxy)phenylene] (CNPPP) as the host and the resultant materials compared with Ir(PPy)3-doped devices. Green electrophosphorescence was observed, with peak emission at about 495 and 515 nm. Among the devices fabricated, highly efficient polymer light-emitting diodes were obtained with CNPPP doped with fac-tris[2-(4-tert-butylphenyl)pyridinato]iridium. An external quantum efficiency of 4.4% (photoluminescence/electroluminescence) and a luminous efficiency of 10 cd A−1 were obtained at 120 cd m−2. These values remain at 4.2% and 10 cd A−1, respectively, at 2500 cd m−2. The improvement is attributed to improved interaction between the guest and host, and to better and more complete energy transfer from the host singlet to the guest triplet state. These results demonstrate that efficient electrophosphorescence is not limited to small molecule organic light-emitting diodes, it can also be achieved in devices made with polymer hosts.

LC pixel capacitance C/sub lc/, which changes with the director of liquid crystal molecules as a function of external applied voltage, has a most important impact on the pixel voltage error /spl Delta/ V/sub p/ and therefore on the electro-optics (E-O) characteristics of the LC pixel for an a-Si TFT LCD. In this paper, the pixel voltage error has been simulated for 10.4" VGA (640/spl times/480) and SVGA (800/spl times/600) a-Si TFT LCD, and in this simulation, we especially took into account the change in LC dielectric constant. We found that /spl Delta/ V/sub p/ changes with the data voltage V/sub p/. In addition, E-O characteristics of LC pixel for an a-Si TFT LCD has been investigated. The result shows that the effect of /spl Delta/ V/sub p/ on E-O characteristics is significant when V/sub p/ ranges from the threshold voltage to the saturation voltage.

It improves efficiency and accuracy for aerodynamic shape optimization to apply parameterization technique with fewer parameters and high fidelity. Class and shape transformation (CST) is a concise and efficient method, nevertheless, it’s difficult to parameterize complicated configurations with unified CST method. This article presents multi-block CST method after analyzing mathematical description of the method, and this method connects adjacent surfaces smoothly as well as retains good properties of CST method. Modeling cases show that it can reduce the number of design variables to represent surface on which curvature distribution is not even, and it can also model the different classes of surfaces smoothly. Aerodynamic shape optimization system is built based on the multi-block CST method, genetic algo-rithms and hypersonic aerodynamic force engineering calculations, and aerodynamic characteristics of a quasi-waverider wing-body vehicle have improved significantly after optimization. The study shows that multi-block CST method with fewer design variables and higher fidelity extends application of CST method dramatically.

During the process of preliminary and conceptual design of hypersonic vehicles, predicting surface friction as well as heat flux is crucial to the design of the thermal protection system (TPS) and optimization of aero-thermodynamics. This paper primarily focuses on two aspects. Firstly, an engineering code has been successfully developed to compute the approximate heating rates of general three-dimensional hypersonic vehicles at angles of attack using unstructured grids for perfect gas. A three-dimensional linear description of surface and flowfield is proposed, based on which an improved axisymmetric analog method is developed, which calculates inviscid surface streamlines and metric coefficients over the body. An implicit surface fitting method is introduced to fit the primary curvatures at stagnation point and a robust marching scheme for calculating heating rates downstream of stagnation region is developed. The proposed engineering approach is verified through a spherically blunted cone and a double ellipsoid, satisfactory agreement between calculation results and wind tunnel experimental results is found. Secondly, a quasi-waverider wing-body model is constructed, the sharp leading-edge of the wing is blunted using circular tips with distinct values of radius, the bluntness effect on the aerodynamic performance is investigated, which would be of vital importance for future work in designing and optimizing the shape of the blunt leading-edge on hypersonic vehicles.

Kai Liu,1 Xiquan Zhang,1 Guangqing Cao,1 Yongjun Liu,2 Chuanzhen Liu,1 Hourong Sun,1 Xinyan Pang1 1Cardiovascular Surgery Department, Qilu Hospital of Shandong University, 2Pharmacy College of Shandong University, Jinan, People’s Republic of China Purpose: To investigate whether inhalation of ethyl pyruvate (EP) encapsulated with poly(ethylene glycol)-block-lactide/glycolide copolymer nanoparticles (EP-NPs) can prevent the development of shunt-flow-induced hyperkinetic pulmonary arterial hypertension (PAH) in a rat model.Materials and methods: Rats were separated into five groups: blank (ie, no treatment after shunt flow), normal control (ie, no shunt flow or treatment), EP-NP instillation, EP-only instillation, and vehicle. The animals received intratracheal instillation of EP-NPs or other treatments immediately after a shunt flow, and treatment continued weekly until the end of the experiment. Hemodynamic data were recorded, pulmonary arterial remodeling was assessed, and levels of inflammatory mediators and ET1 expression in the lung and serum were analyzed. In addition, retention of EP in the lungs of rats in the EP-NP and EP-only groups was measured using high-performance liquid chromatography.Results: After 12 weeks, hemodynamic abnormalities and pulmonary arterial remodeling were improved in the EP-NP instillation group, compared with the blank, EP-only, and vehicle groups (P

High molecular weight, readily soluble copolymers of 9,9-dioctylfluorene and dibenzothiophene (DBTh) comonomer (less than or equal to 50 mol%) are synthesized by Suzuki polycondensation. PL efficiencies and EL external quantum efficiencies of random copolymers decrease with increasing DBTh content. For the alternating copolymer, a PL efficiency of 62% and an EL external quantum efficiency of 0.42% are obtained. Excimer emission is effectively depressed when the DBTh content is greater than 20 mol%. It is indicated that the meta-linkages of 2,8-substitution of DBTh are effective in enhancing blue emission of polyfluorene.