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A double electrical excitation synchronous generator (DEESG) with an embedded brushless exciter is proposed to achieve brushless excitation for a brush excitation electrical excitation synchronous generator (EESG). A set of extra stator excitation windings is placed in the stator slots with armature coils to generate a static magnetic field. There are two sets of windings on the rotor: pulsating excitation winding (Wp) and main excitation winding (WF). The winding direction of the coils of Wp and WF on the same rotor-pole-body is the same. The AC voltage of Wp which is induced by static magnetic field provides dc excitation current for WF by diodes. Both currents in the coils of the Wp and WF generate the rotor excitation flux which induces voltage in the armature coils. In this study, the operating principle is analyzed theoretically. The no-load and load characteristics are studied using Maxwell. The influence of the novel winding structure on the output voltage when the load varies is also analyzed. The voltage regulation rate of DEESG is reduced because the rotor excitation currents can be increased with armature current. A 1.5 kVA prototype is fabricated for experiment. The measured results agree well with the theoretical and FE-predicted results.

Fractional-slot slot harmonic only windings (SHOW), featured by multi-layer and varied coil turn ratios, contain only the torque-generating component and its slot harmonics in stator magnetomotive force (MMF), which makes them attractive. This paper establishes general design principles of SHOW considering different slot/pole combinations and makes detailed comparisons between SHOW and double layer (DL) windings for surface-mounted permanent magnet (SPM) machines. Firstly, fractional slot windings are classified into several categories. Similarity in distribution factors of MMF harmonics is illustrated, based on which, harmonics elimination principle of SHOW is explained. Then, general equations for calculating optimal coil turn ratios for SHOW are derived. Practical ratios approximating the optimal ones are also presented and evaluated. Furthermore, in order to show the superiorities of SHOW, 12-slot/10-pole (12s10p) and 24S10P SPM machines with SHOW are comprehensively studied and compared with their DL counterparts in terms of torque ripple, overload capability, rotor magnet loss, stator iron loss and radial electromagnetic force harmonics. Finally, 12S10P and 24S10P prototypes with SHOW are fabricated and tested for verifications.

Claw pole machines (CPMs) have the advantages of a simple structure and low cost; therefore, they are commonly used in electric vehicles (EV). However, the methods to improve reliability and efficiency should be studied. So, a new type of hybrid excitation claw pole machine (HE-CPM) for EV is proposed. The permanent magnet (PM) is inserted in the rotor, and the field winding is placed on the front and back ending cover. Because the hybrid flux path of the proposed machine is three-dimensional (3D) and 3D finite element analysis (FEA) is time-consuming, a 3D magnet equivalent circuit (MEC) method considering rotor position is proposed and results between 3D MEC and FEA are compared. Particle swarm optimization (PSO) and 3D MEC are combined in the optimization design of HE-CPM. The optimized results prove the effectiveness of the optimization method. Finally, the flux density distribution, electromagnetic characteristics of HE-CPM are evaluated. The thermal analysis and mechanical stress analysis are carried out. The HE-CPM prototype was manufactured. The direct current (DC) bus voltages under different excitation currents and load currents are measured and compared with those of FEA. When the armature current and the excitation current are 7 A and 4 A, respectively, the rated power and rated speed of HE-CPM are 10.28 kW and 3000 rpm, respectively. The maximum efficiency is 89%. FEA results are basically consistent with the experimental results. Accurate results and time savings can be achieved by combining PSO and 3D MEC.

The shaping of the air gap of a V-typed fractional slot concentrated windings interior permanent magnet synchronous machines (IPMSMs) is investigated for compressed-air system (CAS) applications in this article. The harmonics of no-load air gap density, average torque, torque ripple, and iron losses are studied by the finite element analysis (FEA). The results show that the air gap shaping of the V-typed IPMSM can be effectively used to reduce the torque ripple and stator core loss. It is because the low-order harmonics of the air gap flux density can be reduced with a little decrease in the average torque. The proposed air gap shaping methods have the advantages of simple design and simple manufacture. A V-typed IPMSM with air gap shaping is prototyped to verify the correctness of the analysis results.

Electromagnetic force (EMF) voltage distortion, caused by armature reaction, not only deteriorates torque ripple in constant torque region but also reduces the flux weakening operation region, especially for fractional slot permanent magnet (PM) machines. This article mitigates voltage distortion by varying coil distribution and turn ratio with employment of triple layer (TL) and quadruple layer (QL) windings with varied coil turns. Coil turn ratios of TL and QL windings are optimized to minimize voltage distortion ratio. Reduction mechanisms are exhaustively analyzed. It is found that, for the TL winding with optimal turn ratio, the armature leakage flux and PM leakage flux in tooth tips will not reverse polarities simultaneously, resulting in much lower voltage distortion. On the other hand, for the QL winding, voltage distortion reduction is realized by lowering the amplitude of armature tooth tips leakage flux. Compared with conventional double or single layer (SL) winding machines, torque ripple can be reduced and flux weakening capability is greatly enhanced. The 12-slot/10-pole prototypes with both SL and optimum TL windings are fabricated and tested to verify the analysis.

The static excitation part of a brushless wound rotor hybrid excitation generator without an exciter (brushless WRHEG) is analyzed in this paper. The DC stator excitation windings and rotor harmonic coils are placed in the iron core as the excitation part, so that the brushless excitation for a wound rotor hybrid excitation generator (WRHEG) can be realized. In this study, the selection of stator excitation windings and rotor harmonic coils, which are essential for achieving of the brushless excitation, is providing. The effect of the static magnetic field on the air-gap magnetic field is studied theoretically. The harmonic content of the air-gap magnetic field is analyzed by Fourier series form and the effect of harmonics on the output voltage is also investigated. The influence of the static excitation field on the iron loss is also considered. A 1.5 kVA prototype is fabricated to verify the validity of the theoretical and Finite Element (FE) analysis. The output voltage under the no-load and the rated load conditions are measured. The field regulation capacity and the efficiency of the brushless WRHEG are tested. It shows that the brushless excitation is achieved by remaining the operating performance of WRHEG unchanged.

This study deals with the optimisation of surface-mounted permanent-magnet (SPM) motor for the vehicle door of high-speed railway transport systems, where both high-output torque under healthy conditions and low braking torque under fault conditions are required. The split ratio of rotor outer diameter to stator outer diameter is one of the most important design parameters due to its significant impact on the output torque. As found in this study, it also has significant effect on the braking torque. Therefore, the split ratio for SPM machine with consideration of braking torque is investigated. The relationships between the split ratio and both the output and braking torque are analytically established. It is found that the maximum output torque and the maximum braking torque correspond to the same split ratio. Therefore, considering the short-circuit operating condition of the door system, the split ratio related to the maximum output torque no longer satisfies its requirements. It is demonstrated that the split ratio can reduce the braking torque under a short-circuit fault. The analytical results are verified by the finite-element analyses. The experiments on the prototype 12-slot/10-pole SPM machine validate the analyses.

Purpose: The aim of this study is to evaluate the influence of arm movements from adduction to abduction on intracavitary electrocardiogram and the position of a catheter tip. Methods: Overall, 192 peripherally inserted central catheter lines were placed under intracavitary electrocardiogram guidance and 188 of them were enrolled in the study. The catheter was first placed at a time point corresponding to the peak P wave with the arm in adduction. The arm was then abducted to 90° without changing catheter insertion length. During the procedure, basal electrocardiogram, intracavitary electrocardiogram, and radiographs with the arm in adduction and abduction were recorded. Amplitude wave changes and catheter movements were measured on electrocardiogram records and radiographs, respectively. Results: In 188 cases, the P wave displayed typical changes, and 97.8% (184/188) catheters were successfully placed correctly. At the peak P wave, the amplitude of the peak P wave was 8.64 times greater than that of the basal P wave, and the P/R ratio was 0.61. When the arm was abducted to 90°, the amplitude of the P wave dropped to 57% of its peak, P/R decreased from 0.61 to 0.34, and the catheter tip moved cephalad 1.00 and 0.77 vertebral body units in male and female patients, respectively. Conclusion: Peripherally inserted central catheter moves toward the heart when the arm position changes from abduction to adduction. Peripherally inserted central catheter tip placement at the peak P wave with patient’s arm in adduction is accurate and can prevent the catheter from advancing too low. R wave can function as a reference for observing P wave changes during peripherally inserted central catheter placement.

For the five-phase permanent magnet (PM) machines with conventional Halbach array rotor, although the third harmonic current is injected into the phase current, the torque density hardly increases due to the absence of the third harmonic air gap flux density. Hence, a Halbach array considering third harmonic air gap flux density is proposed in this paper, and the topology is described and compared with the conventional Halbach array. The magnetizing angle of the proposed Halbach array and the stator teeth width are optimized based on the nonlinear programing method. The electromagnetic performances of the five-phase PM machines with the proposed Halbach array, including open-circuit flux density, back electromotive force, flux density under the rated load, cogging torque, average torque, torque ripple, loss, and efficiency, are compared with the PM machine with conventional Halbach array by finite-element method. It is demonstrated that the torque density and efficiency of the PM machine with the proposed Halbach array are higher than that of the PM machine with conventional Halbach array. Finally, the five-phase 10-slot/8-pole PM machines with proposed Halbach array is manufactured and tested to verify the analysis.

In modern aerospace electromechanical actuators (EMA), the integrated structure has brought many advantages, such as reducing system components and system volume, etc. In this paper, the design of dual three-phase winding permanent magnet synchronous machine (PMSM) for an integrated EMA is addressed. The motor adopts slot pole combination of 12/10 because of a high winding factor and utilization. The motor is integrated with the EMA system, so the size of it is strictly restricted. Under the condition of limited size, the most suitable stator split ratio is found by analytical calculation and then verified through finite element simulation. Then through the analysis and comparison of three winding configurations, the double-layer winding phase shift 180 degree is selected. Finally, in the case of considering the eddy current loss on the rotor, the optimal design is carried out to obtain the optimal output torque and reduce the torque ripple.

In this paper, the braking torque of the surface mounted permanent magnet (SPM) motor for the electric sliding plug door (ESPD) system of the rail transport is studied. When the three-phase armature coils are short- circuited, the braking torque should be small to ensure passengers can open the door by themselves. The relationship between the impedance of the three-phase armature coils and the braking torque is deduced. The variation law of motor stator phase resistance and braking torque is obtained. The output torque and braking torque of motor with different stator phase resistance is compared. The model of the motor is built. A prototype of 12-slot/10-pole surface mounted permanent magnet synchronous (SPM) motor is designed and manufactured. The results of the experiment agree well with the theoretical and FE-simulation results.

This paper presents a novel consequent-pole permanent magnet (CPM) machine featuring N-S-iron–S-N-iron sequences to eliminate the even-order harmonics of phase back electromotive force (EMF) and the unipolar leakage flux in the end region. The flux barrier is employed to improve the symmetry of the air-gap flux and reduce the saturation of the stator yoke, and hence the output torque can be improved. The proposed CPM machine, as well as its conventional counterpart with N-iron sequences, is optimized by finite-element analyses. Moreover, the electromagnetic performance of the proposed CPM machine, including the open-circuit air-gap flux density, back EMF, average torque, torque ripple, loss, efficiency, and unipolar leakage flux, is compared with the conventional CPM and surface-mounted PM (SPM) machines. Although both the proposed and conventional CPM machines have lower output torque than the SPM machine, the utilization ratio of PM material is increased by >33%. It is demonstrated that the proposed CPM machine has similar output torque and efficiency, but much lower torque ripple compared to the conventional one. Moreover, unipolar leakage flux does not exist in the end shaft of the proposed machine, and thus, the magnetization of the mechanical components can be effectively eliminated. Finally, the 9-slot/6-pole CPM machine is prototyped and measured to validate the analyses.

Stator core loss of four interior permanent magnet (IPM) machines is studied for electric vehicle applications in this paper. The no-load air-gap density, core loss density, core loss harmonics, and the segregation of hysteresis and eddy current losses are investigated with finite-element analysis. The results show that the rotor surface shaping of a single-layered IPM machine and increasing the rotor magnet layers can reduce the stator core loss due to the harmonics of the rotor magnetomotive force. The stator core loss reduction effectiveness of rotor surface shaping is similar to a two-layered magnet configuration, but the reduction effectiveness is less than that the magnet layers increased to three numbers. An IPM machine with three-layered magnets rotor is prototyped to verify the analysis.

This paper aims at solving the electrical engineering teaching problems caused by the new coronavirus pneumonia epidemic. The theory of Outcome Based Education (OBE) is studied Guide the online teaching work. Combined with professional features, different online teaching methods will be introduced. The advantages and disadvantages of each method will be compared. Through practice and exploration, online teaching has achieved good result. The students' learning progress is not affected by the Epidemic.

Hypertension, a common chronic disease, is a leading cause of death and other cardiovascular diseases. Recent studies show that an inflammatory factor named retinol binding protein 4 (RBP4) was increased with cardiovascular diseases. However, the relationship between RBP4 and hypertension in patients remains unclear.The study cohort was composed of patients with essential hypertension (EH) and healthy control (HC) subjects from the Second Affiliated Hospital of Nanjing Medical University [2017-2019]. The levels of RBP4 and echocardiography were compared in the current study. Statistical differences between two groups were analyzed using unpaired Student's t-tests and the correlation between the two variables adopts Pearson correlation analysis. SPSS 23.0 was used for all statistical analysis.Analysis of patient plasma samples revealed that RBP4 in EH group was greater than HC group (P0.05). The area under the ROC curve was 0.717. Specificity and sensitivity were 80.4% and 60.8%, respectively. RBP4 had positive correlation with left ventricular systolic diameter (LVDs), interventricular septal thickness (IVS) and left ventricular posterior wall thickness (LVPW), negative correlation with left ventricular shortening fraction (FS) and ejection fraction (EF) (P0.05), and no correlation with left ventricular end-diastolic diameter (LVDd) (P0.05). RBP4 was closely related with E/A, evaluation method of left ventricular diastolic function, in patients with EH.RBP4 levels are closely correlated with blood pressure (BP) levels and might be involved in the regulation of left ventricular diastolic function in patients with EH.

An interior permanent magnet (IPM) machine with ∇ + U shape rotor topology is proposed and its electromagnetic performance with typical V shape and ∇ shape for electric vehicle (EV) applications are compared. The pole-arc to pole-pitch ratios are optimized to maximize the fundamental air-gap flux density and minimize its total harmonic distortion (THD) of all the three IPM machines by the finite element (FE) method. It can be obtained that ∇ + U shape rotor topology has the lowest THD of the air-gap flux density. The back electromotive force and its THD orders, cogging torque, torque density, torque ripple, d - and q -axis inductances, saliency ratio, and iron loss of three machines are analyzed and compared. It is demonstrated that the ∇ shape IPM machines have the highest average torque, and the torque ripples of the V shape and ∇ shape machines are almost the same. The ∇ + U shape IPM machine has the lowest torque ripple and iron loss with only a little reduction of average torque. Finally, the ∇ + U shape IPM machine is prototyped to verify the results of the FE analysis.

An interior permanent magnet (IPM) machine with ∇+U shape rotor topology is proposed for electric vehicle applications whose iron loss and efficiency are compared to that of typical V shape and ∇ shape machines. The air-gap flux density, flux-density waveform, and its harmonics on stator core and rotor core are analyzed. It can be obtained that ∇+U shape rotor topology has the lowest total harmonic distortion. The torque ripple, core loss, core loss density, PM eddy-current loss, d - and q -axis inductances, saliency ratio, characteristic current, and efficiency of three IPM machines are analyzed and compared. It is demonstrated that the efficiency of ∇+U shape IPM machine is higher than V shape and ∇ shape machines, particularly under high-speed operation, because the iron loss of the ∇+U shape machine is the lowest. With the increase of PM layer, the PM eddy-current loss is increased, PM segmentation can effectively reduce the PM eddy-current loss. Finally, the ∇+U shape IPM machine is prototyped to verify the results of the finite element analysis.

The magnet eddy-current losses of six interior permanent magnet (IPM) machines are investigated for electric vehicle applications in this paper. The armature field, eddy-current density of magnet, the influence of PM depth, the distance of PM layers, and the number of PM segmentation are studied by finite-element analysis. It is demonstrated that increasing the PM depth of first layer and the distance of PM layers can provide more soft iron space for the armature-reaction flux, which can reduce the magnet eddy-current loss. PM segmentation can effectively reduce the PM eddy-current loss, because the eddy-current paths are divided into smaller loops, increasing the effective resistance. An IPM machine with segmented PM is prototyped to verify the analysis.

In general, the brushless wound rotor hybrid excitation synchronous generator (HESG) needs a separate exciter. In this paper, a novel integrated brushless excitation HESG (IBE HESG) is developed by integrating the excitation section into the iron core of wound rotor HESG. Compared with the conventional brushless excitation method, the axial length of the IBE HESG is shorter and the original topology of the wound rotor generator is not changed. The excitation section has two sets of windings: stator excitation windings and rotor armature windings. The stator excitation windings are installed in the stator slots evenly. The static excitation field is established by the dc excitation current of the stator excitation windings. The rotor armature windings are buried in the rotor armature slots around the rotor. The static excitation field induces a voltage in the three-phase rotor armature windings and supplies the dc current to the rotor excitation windings through a rotating rectifier on the rotor. The magnetic field distribution is analyzed by the frozen permeability method to decouple the multimagnetic circuits. Also, the influencing factors of excitation efficiency are studied and the parameters of the IBE HESG are obtained to achieve a reasonable excitation characteristic. Finally, the theoretical analysis is confirmed by the experiments on a 1.5 kVA/50 Hz prototype generator. The results show that the output power can be regulated over a wide range.

This paper proposes a novel integrated brushless excitation method (IBEM) for a rotor-excited generator. IBEM is applied to a rotor-excited hybrid excitation synchronous generator (HESG) to realise brushless excitation while the key features of the rotor-excited generator are maintained. The new generator is referred as IBE HESG here. The stator excitation windings are buried in the stator slots. The static excitation field is established in the air gap when there is dc excitation current in the stator excitation windings. The three-phase armature coils of the rotor induce the static excitation field and provide the dc excitation current for the rotor excitation windings via a rotating rectifier. The operating principles are discussed theoretically. The magnetic field distribution and the operating characteristics are studied by finite-element analysis. The no-load, external, regulation and excitation characteristics are analysed. Compared with the brush excitation HESG, the rotor excitation current is able to meet the requirement and the output voltage is conveniently regulated by the stator excitation current. Finally, a 1.5 kVA prototype is fabricated to test the operating characteristics of IBE HESG. It demonstrates that the brushless excitation is realised and the output voltage is regulated by the stator excitation current.

Curcumin, which is the effective component of turmeric (Curcuma longa), has previously been shown to exert potent antioxidant, antitumor and anti‑inflammatory activities in vitro and in vivo. However, the mechanism underlying the protective effects of curcumin against oxidative damage in endothelial cells remains unclear. The present study aimed to examine the effects of curcumin on hydrogen peroxide (H2O2)‑induced apoptosis and autophagy in EA.hy926 cells, and to determine the underlying molecular mechanism. Cultured EA.hy926 cells were treated with curcumin (5‑20 µmol/l) 4 h prior to and for 4 h during exposure to H2O2 (200 µmol/l). Oxidative stress resulted in a significant increase in the rate of cell apoptosis, which was accompanied by an increase in the expression levels of caspase‑3 and B‑cell lymphoma 2 (Bcl‑2)‑associated X protein (Bax), and a decrease in the expression levels of Bcl‑2. Treatment with curcumin (5 or 20 µmol/l) significantly inhibited apoptosis, and reversed the alterations in caspase‑3, Bcl‑2 and Bax expression. Furthermore, curcumin induced autophagy and microtubule‑associated protein 1A/1B‑light chain 3‑Ⅱ expression, and suppressed the phosphorylation of Akt and mammalian target of rapamycin (mTOR). These results indicated that curcumin may protect cells against oxidative stress‑induced damage through inhibiting apoptosis and inducing autophagy via the Akt/mTOR pathway.

To improve the power density of aviation electric drive system, the high-speed permanent magnet machines has more and more popular in the air compressor, radial compressor, and electro-hydrostatic actuator applications. Two methods have studied to reduce the rotor eddy current losses in high-speed permanent magnet machines in this paper. Firstly, rotor eddy current losses at different stator slot openings are investigated, the stator core loss are considered simultaneously. Secondly, to reduce the magnet eddy current loss in carbon fiber retaining sleeve, the copper shield is added between permanent and carbon fiber, and the rotor eddy current losses at different copper shield width are studied.

The emergence of wide-bandgap power devices such as silicon carbide (SiC) MOSFETs can achieve much faster switching speeds, hence lower switching loss, than conventional silicon (Si) IGBTs. However, the faster switching speed, hence higher dv/dt can cause increased turn-on current overshoot, ringing and EMI due to the parasitic capacitance in the system. In this paper, the parasitic capacitance of a filter inductor has been analysed, where a single-layer power inductor with an EE core and rectangular conductors is used to study the factors which affect the parasitic capacitance. Methods to reduce the parasitic capacitance are proposed and analysed with the parasitic capacitance function obtained. The relationship between the parasitic capacitance and design variables such as winding pitch, thickness and dielectric constant of the insulation layer, turn-to-core distance and potting material are studied. The influence factors which can reduce the parasitic capacitance are analysed both by theoretical calculation and Finite Element Analysis (FEA). Three practical methods for reducing the parasitic capacitance are studied based on theoretical formulas. The values of the influence factors and the corresponding minimum of the parasitic capacitance are obtained by the parasitic capacitance function. The results are verified by experiment.

Background and purpose Periostin, a matricellular protein, plays an important role in cardiac development and remodeling. Its expression profile and the association with myocardial fibrosis have not been investigated in human failing hearts. This work aimed to explore the behavior and pathologic significance of periostin in signifying collagen fibrogenesis in human hearts from patients with end-stage heart failure. Methods and subjects Tissues were collected from heart transplant recipients and the control hearts were from unmatched donors. Periostin mRNA and protein were detected using quantitative real-time polymerase chain reaction and Western blotting. Immunohistochemistry staining was employed to directly detect the protein level and distribution of periostin in heart tissues. The extent of myocardial fibrosis was expressed by the percentage of Masson's trichrome staining. Gelatin zymography was used to detect the activities of matrix metalloproteinase (MMP)2 and MMP9. Results A low level of periostin mRNA expression was found in control hearts while not detectable at the protein level. Periostin mRNA was increased significantly in failing myocardium compared to that of controls. Periostin was distributed extensively in left ventricle and interventricular septum of the failing hearts. Correlation analysis showed periostin protein expression was positively associated with myocardial fibrosis as well as left ventricular diastolic dimension. The distribution and extent of periostin was consistent with that of myocardial fibrosis. MMP2 activity has an obvious increase about fourfold in heart tissues from HF patients. But there is no quantitative association with the expression of periostin. Conclusions Periostin, the distribution and expression of which were consistent with the extent of myocardial fibrosis, might be a potential biomarker of cardiac remodeling in heart failure patients.

This paper presents torque density improvement of ferrite assisted synchronous reluctance machines by optimizing the rotor stucture. It is found that adding the circumferential direction PMs can increase the PM field and thereby improving the PM torque. The PMASynRM characteristics such as flux density, Ld and Lq, demagnetization are represented, PM torque, reluctance torque, torque ripple, field weakening and power factor of two models are compared by finite element analysis. As a result, the optimal PMASynRM shows the substantially improved performance compared with the initial design.

In this paper, two novel brushless excitation methods for wound rotor excitation synchronous generators are proposed in this paper. Compared with the electric excitation synchronous generators with an exciter, these two kinds of generators can integrate the function of the exciter into the main generator. The exciter can be eliminated. The axial length of the generation system can be shorten. The structures and operating principles of two novel generators are introduced. The magnetic field distributions are obtained by Finite Element Analysis. The operating characteristics of two generators are simulated and compared. These two brushless excitation methods can be applied in the areas such as aerospace generation system, wind power generator, electric vehicles and so on.

Objective To investigate the expression of OX40 ligand(OX40L) on C-reactive protein(CRP)-triggered mouse aorta endothelial cells (MAECs) in vitro. Methods MAECs from aorta were isolated by digestion with collagenase typeII. The cell growth was confirmed by morphological characteristics and the immunological marker, factor VIII(or Willebrand factor, vWF). The expression of OX40L by MAECs was detected by RT-PCR and western blot after incubating with 100μg/ml CRP for 48 hours. Results Twenty-day cultures of MAECs formed confluent monolayer of a cobblestone pattern. RT-PCR and western blot assay showed that the level of OX40L expression in MAECs receiving CRP treatment was higher than control. Conclusion A reliable method is described to isolate and propagate MAECs. CRP upregulates OX40L expression in MAECs.

Objective The aim of this study was to design a high intensity swimming training and two-kidney, one-clip (2K1C) hypertension protocol in Sprague–Dawley (SD) rats and to use current echocardiography techniques to examine the differential diagnosis between physiological and pathological left ventricular hypertrophy. Methods One group of SD rats performed swimming training at high intensive swimming training (HIGH) for eight weeks. In animals of the other arm of the study, a 2KIC hypertension was created and maintained for eight weeks. Results After eight weeks, all rats were studied by standard and tissue Doppler echocardiography. The heart weight/body weight ratio (HW/BW) of 2K1C and HIGH rats increased by 16% and 42%, respectively. Echocardiography showed increased septal and posterior wall thickness in both the 2K1C and HIGH rats. Left ventricular increased by 35 and 41% respectively. Left ventricular diameters, stroke volumes, cardiac output, and ejection fractions were unchanged in either group. Mitral inflow showed a decrease in late-wave velocity, thus increasing the E/A ratio in HIGH rats. However, mitral inflow showed an increase in late-wave velocity, thus decreasing the E/A ratio in 2K1C rats. There was a significant increase in Ea and early diastolic (Em)/late diastolic (Am) in HIGH rats in basal septum and lateral mitral valve annulus. And there was a significant increase in Am, which led to a significant decrease of Em/Am in 2K1C rats. No significant change occurred in pulmonary vein systolic velocity and diastolic velocity, in either of the three animal groups. However, there was significant increase in atrial reversal velocity in HIGH rats. Conclusions Doppler echocardiographic parameters of LV diastolic function can be of diagnostic importance for discrimination between pathologic and physiologic LV hypertrophy.

C-reactive protein (CRP) is an important predictive factor for cardiac disorders including acute myocardial infarction. Therapeutic inhibition of CRP has been shown to be a promising new approach to cardioprotection in acute myocardial infarction in rat models, but the direct effects of CRP on cardiac myocytes are poorly defined. In this study, we investigated the effects of CRP on cardiac myocytes and its molecular mechanism involved. Neonatal rat cardiac myocytes were exposed to hypoxia for 8 h. Hypoxia induced myocyte apoptosis under serum-deprived conditions, which was accompanied by cytochrome c release from mitochondria into cytosol, as well as activation of Caspase-9, Caspase-3. Hypoxia also increased Bax and decreased Bcl-2 mRNA and protein expression, thereby significantly increasing Bax/Bcl-2 ratio. Cotreatment of CRP (100 mug/ml) under hypoxia significantly increased the percentage of apoptotic myocytes, translocation of cytochrome c, Bax/Bcl-2 ratio, and the activity of Caspase-9 and Caspase-3. However, no effects were observed on myocyte apoptosis when cotreatment of CRP under normoxia. Furthermore, Bcl-2 overexpression significantly improved cellular viability through inhibition of hypoxia or cotreatment with CRP induced Bax/Bcl-2 ratio changes and cytochrome c release from mitochondria to cytosol, and significantly blocked the activity of Caspase-9 and Caspase-3. The present study demonstrates that CRP could enhance apoptosis in hypoxia-stimulated myocytes through the mitochondrion-dependent pathway but CRP alone has no effects on neonatal rat cardiac myocytes under normoxia. Bcl-2 overexpression might prevent CRP-induced apoptosis by inhibiting cytochrome c release from the mitochondria and block activation of Caspase-9 and Caspase-3.

Hybrid Excitation Synchronous Machine (HESM) combines the merits of high power density and good capability of air-gap magnetic field adjustment. A novel Tangential/Radial Hybrid Excitation Synchronous Machine (T/R-HESM) is proposed in this paper. Its structure and operation principle are introduced. The magnetic field distribution and static characteristics are obtained by finite element method (FEM). They indicate that magnet congregate effect of shunt-wound magnetic path is significant because of the special structure. The static characteristics of T/R-HESM are much better than that of EESM. A prototype is produced to take an experimental study, including load and no-load experiments. The experimental results verify the correctness of electromagnetic design and simulation, which demonstrate high performance of T/R-HESM. With the advantages of simple configuration, completely air-gap magnetic flux adjustment and great controllability, T/R-HESM has considerable application potentials in various fields.