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The authors investigate a semi‐flooded cooling technology for modular permanent magnet machines using flux gaps (FGs) in alternate stator teeth for extra cooling channels. The investigated machine is separated into stationary and rotational components by a polyether ether ketone sleeve. Liquid is directed into the stationary component to achieve a significant temperature reduction, at the same time, avoiding the liquid leakage into the rotating component that will cause an increase in friction losses. The FGs in the modular machine increase the contact area between coolant and machine components, resulting in better cooling efficiency. Furthermore, the FGs contribute to reduced pressure loss by minimising system flow resistance. The influence of the FG width on improving machine cooling efficiency, lowering machine temperature, and reducing pressure losses is delved. Additionally, the investigation considers the impact of inlet and outlet areas to reveal the influences stemming from fluid expansions and contractions in these regions. Computational fluid dynamics (CFD) modelling is employed to simulate the cooling performances of the investigated machines. In addition, the flow network analysis has also been employed to help understand the fluid behaviour within machines. A series of tests have been carried out to validate the CFD modelling. [ABSTRACT FROM AUTHOR]

In this study, we have studied the influence of nitrogen content on the mechanical properties of nanostructure medium entropy (TiVCrAl)Nx films prepared by magnetron sputtering. A transition from body-centered cubic nanocrystalline phases to an face-centered cubic columnar crystal structure has been observed in the medium entropy films as the nitrogen flow increases. With increasing nitrogen flow, the lattice constant of the film first increases and then decreases due to the change of composition from substoichiometric to overstoichiometric, resulting in the different bond length of Metal-N. The hardness of the films first increases and then decreases with the increase of nitrogen flow. When the nitrogen flow was 25 sccm, the hardness reached the maximum value of 23.1 GPa. Moreover, the film has shorter cracks length and a higher hardness/modulus ratio, exhibiting enhanced fracture toughness. The increased hardness primarily results from the formation of bonds between metals and nitrogen and the strengthening of a solid solution and a grain boundary. [ABSTRACT FROM AUTHOR]

Wind farms play a crucial role in renewable energy generation, but their reliability is often compromised by complex environmental and equipment conditions. This study proposes a field of view enhanced convolutional neural network (CNN) model for fault diagnosis and prevention in wind farms. The model is developed by collecting and processing wind farm fault data and compared with support vector machine (SVM) and k-nearest neighbor (KNN) models. The results showed that the proposed CNN model outperformed the other models in terms of convergence speed (17 iterations to reach the minimum loss), fault diagnosis accuracy (99.3% and 99.2% for inner and outer circle faults, respectively), and stable power output improvement. The model's application to maintenance scheduling and economic benefit analysis in a real wind farm case demonstrated its high consistency and accuracy in fault prediction and maintenance optimization. The proposed approach has the potential to enhance wind farm reliability, efficiency, and economy by enabling accurate fault diagnosis, early warning, and preventive maintenance. [ABSTRACT FROM AUTHOR]

The use of honey as food and medicine is widespread, but insufficient data support that it is safe, especially when consumed in high doses. As a result, the present work aimed to investigate the potential toxicity using a repeated dose oral toxicity study. In the toxicity study, Wistar rats were divided into five groups, and orally administered with distilled water (control), 3, 6, 12, and 24 g/kg body weight (BW)/day of honey for 28 days in a row. Body weight, food consumption, clinical pathology, and histopathology were then examined. Significant suppression of body weight, food consumption, and body weight gain was observed at the dose of 24 g/kg BW in both sexes. Honey administration had no statistically significant effect on any of the haematological parameters. The clinical observations, blood coagulation and biochemical parameters, target organs, or histopathology did not reveal any additional nor other treatment-related adverse effects. Mild pathological changes in hepatic tissues were observed in the control, 12, or 24 g/kg BW dose groups, which were common spontaneous lesions unrelated to honey treatment. In the 24 g/kg BW group, one male rat showed non-specific reactions such as focal basophilic change of renal tubule cells, which were also regarded as spontaneous lesions. Based on these results, the no-observed-adverse-effect level (NOAEL) of honey in this repeat dose oral toxicity study was determined to be 12 g/kg BW in both sexes of Wistar rats. [ABSTRACT FROM AUTHOR]

Hybrid improper ferroelectricity (HIF) has been proposed as a candidate approach to create room- temperature multiferroic materials with an intrinsic electric-field controlled magnetism effect, and HIFs in bi-layered Ruddlesden-Popper Ca3-xSrxTi2O7 ceramics have been confirmed in the present work. The ferroelectric hysteresis loops are observed in these ceramics at room temperature, and the polar orthorhombic structures with oxygen octahedral rotation and tilt modes have been confirmed by room-temperature X-ray powder diffraction. The amplitudes of oxygen octahedral rotation and tilt modes decrease with the increasing x value, which in turn leads to the decrease of remnant polarization in these ceramics. A first-order phase transition has been evidenced by the differential scanning calorimetry measurement, and the temperature of phase transition decreases linearly with the increasing content of strontium cations. It is found that the amplitude of oxygen octahedral distortion is the dominating factor that affects ferroelectric polarization in partial-ordered bi-layered Ca3Ti2O7-based ceramics. [ABSTRACT FROM AUTHOR]

Surface mounted permanent magnet Vernier (SPM-V) machines, because of their high torque density and multi-pole structure, are promising candidates for low-speed direct-drive applications. To achieve high torque density, the SPM-V machines are generally designed with high gear ratios. Therefore, their operating frequencies can be much higher than those of the conventional SPM machines. This potentially increases the alternating current (AC) winding losses, especially those with form-wound coils proposed for high-power applications. This article investigates the AC losses (including skin effect, proximity effect, rotor PM induced, and circulating current losses) in form-wound stator coils of a 3 MW direct-drive SPM-V machine with different slot/pole number combinations. The study reveals that the SPM-V machines have significantly higher AC winding losses than their conventional SPM counterparts for similar operating conditions. To reduce the AC winding losses in SPM-V machines, a novel flux shunt concept is proposed along with other conventional techniques such as increasing the number of turns/coil (with terminal voltage being kept constant) and parallel strands/turn, providing extra clearance at slot opening. With the loss reduction techniques implemented, the SPM-V machines can achieve comparable efficiency but much higher torque density than their conventional counterparts. Moreover, the proposed flux shunt was also found to be very effective in reducing the potential risk of permanent magnet (PM) irreversible demagnetization, a key issue for SPM-V machines at high power ratings. [ABSTRACT FROM AUTHOR]

The structure and magnetic properties in doped Heusler alloys of Mn2CoGa and Mn2CoAl have been investigated by experiments and calculations. The main group elements of Ga or Al in the systems are substituted by the magnetic or non-magnetic transition metals, Co, Cu, V, and Ti. Three kinds of local ferromagnetic structures, Co-Mn-Co, Mn-Co-Mn, and Mn-Co-V, have been found. They embed in the native ferrimagnetic matrix and increase the magnetization with different increments. The Co-Mn-Co ferromagnetic structure shows the largest increment of 6.18μB/atom. In addition, interesting results for non-magnetic Cu increasing the magnetization and the V atom having a large ferromagnetic moment of about 1.0μB have been obtained. The exchange interaction energy can be increased by the newly added Co and depleted by supporting a ferromagnetic coupling in other substitution cases and showing the variation of the TC. Our calculation of electronic structure verifies the strong d-d hybridization when the three ferromagnetic structures are achieved. It has also been found that the covalent bonding from the Ga and Al determines the generation of the local ferromagnetic structure and the tolerance for dopant content. [ABSTRACT FROM AUTHOR]

The structure, magnetism, magnetic compensation behavior, exchange interaction, and electronic structures of Co50-xMn25Ga25+x and Co50-xMn25+xGa25 (x = 0-25) alloys have been systematically investigated by both experiments and first-principles calculations. We found that all the samples exhibited body centered cubic structures with high degree of atomic ordering. With increasing Ga content, the composition dependence of lattice parameter shows a kink point at the middle composition in Co50-xMn25Ga25+x alloys, which can be attributed to the enhanced covalent hybridization between the main-group Ga and the transition-metal atoms. Moreover, a complicated magnetic competition has been revealed in Co50-xMn25Ga25+x alloys, which causes the Curie temperature dramatically decrease and results in a magnetic moment compensation behavior. In Co50-xMn25+xGa25 alloys, however, with increasing Mn content, an additional ferrimagnetic configuration is established in the native ferromagnetic matrix, which causes the molecular moment monotonously decrease and the exchange interaction enhance gradually. The electronic structure calculations indicate that the Co50-xMn25+xGa25 alloys are likely to be in a coexistence state of the itinerant and localized magnetism. Our study will be helpful to understand the nature of magnetic ordering as well as to tune magnetic compensation and electronic properties of Heusler alloys. [ABSTRACT FROM AUTHOR]

This article investigates the impact of scaling on the electromagnetic performance of surface-mounted permanent-magnet Vernier (SPM-V) machines with a main focus on open-circuit induced Electro Motive Force (EMF). Three different power ratings, i.e., 3 kW, 500 kW, and 3 MW, have been chosen for this article. For each power rating, the SPM-V machines are analyzed for different slot/pole number combinations to compare their optimal performance with a conventional SPM machine. Step-by-step development of an analytical equation is presented for the prediction of induced EMF taking into account the interpole leakage of rotor permanent-magnets. 2-D finite-element analysis (FEA) has been used to validate the analytical equation across different power ratings. The analytical equation is thereafter utilized to study the influence of different geometric parameters on the performance of the SPM-V machines. It reveals that the back EMF and torque of SPM-V machines, for a given normalized pole pitch (rotor pole pitch to magnetic airgap length), are unaffected by the increase in airgap length due to scaling. However, the power factor of SPM-V, unlike the conventional SPM, reduces significantly with the increase in electrical loading due to the scaling effect. The analytical model for induced EMF and the 2-D FEA predicted results are validated by experiments using conventional SPM and SPM-V machine prototypes. [ABSTRACT FROM AUTHOR]

A total of three types of doubly salient synchronous reluctance machines have been comparatively studied to improve the torque performance using current harmonic injection methods. These machines are derived from the switched reluctance machines (SRMs) with different winding configurations, such as the double/single-layer mutually coupled SRMs (MCSRMs) and fully pitched SRMs (FPSRMs), by supplying them with sinewave current. Such current supply mode can lead to higher torque/power density and lower vibrations and acoustic noise compared with the conventional rectangular current supply. The proposed torque analytical model can predict the instantaneous torque of the doubly salient SRMs with sinewave current excitation and the current harmonics also can be selected in order to reduce the torque ripple and/or increase the average torque. It has been found that the third current harmonic injection shows the best performance for single-layer MCSRMs and FPSRMs because it improves the average torque and reduces the torque ripple at the same time. However, it has little influence on doubly-layer MCSRMs. To improve the torque performance of such machines, other harmonic currents, e.g., fifth and seventh, need to be used. Both static and dynamic tests have been carried out to validate the predictions. [ABSTRACT FROM AUTHOR]

This paper investigates the contribution of each order inductance harmonic to the torque (both average torque and torque ripple) of multiphase doubly salient synchronous reluctance machines (DS-SRMs). Such machines are similar to switched reluctance machines but supplied with sine wave currents. The investigations in this paper are as follows. First, a general analytical torque model based on Fourier series analysis of inductances has been built for machines with different phase numbers, slot/pole number combinations, and also winding configurations. The instantaneous torque for DS-SRMs with any given phase number can then be accurately predicted. Using such model, contribution of each order inductance harmonic to torque can be investigated separately. It is found that the torque ripple frequency of the DS-SRM only depends on phase number. For example, for an m-phase machine, there will be m $\times $ kth-order torque ripple if mod(mk, 2) = 0, where m is the phase number and k is a natural number. This paper also explains why certain phase numbers inherently produce lower torque ripple than others. The findings in this paper provide a future direction for potential torque ripple reduction methods either from machine design or advanced control. The simulations have been validated by experiments using a six-phase DS-SRMs. [ABSTRACT FROM AUTHOR]

In order to maximise utilisation of nutrients for ruminants, researchers directed the supply of nitrogen and organic matter synchronously to the rumen. In the current research, two experiments were conducted, one using the in situ nylon bag technique and the other using in vivo study. In Experiment 1, dynamic degradation rates of organic matter (OM) and nitrogen of each feedstuff were determined using the in situ nylon bag technique. Accordingly, three diets were formulated with the same chemical components, but differing in synchrony index (0.74, 0.85 and 0.97). Experiment 2 was subsequently carried out in vivo to evaluate the influence of diet synchrony on rumen fermentation, productive performance, immunity status and endocrine in Chinese Holstein cows. Rumen degradability of OM and neutral detergent fibre (NDF) and total tract digestibility of OM were linearly increased with the increase of synchrony index, respectively (P < 0.05). Total volatile fatty acids concentration of rumen fluid was increased linearly with the increase of synchrony index (P < 0.05). Meanwhile, rumen ammonia nitrogen concentration and blood urea nitrogen concentration were decreased in cows with the increase of synchrony index, (P < 0.05). Microbial crude protein production, the efficiency of microbial protein synthesis, and milk protein percentage, were linearly increased with the increase of synchrony index (P < 0.05). Serum concentrations of prostaglandin E2 and immunoreactive fibronectin-γ were linearly decreased with the increase of diet synchrony index (P < 0.05). The aforementioned results implicate that an increase of diet synchrony index could improve diet's nitrogen utilisation, apparent digestibility of OM, and NDF. Additionally, it could promote rumen fermentation capacity, productive performance and immunity status in dairy cows. With the consideration of maximising nutrient utilisation, diet synchrony was investigated in the present research. Diets with a higher synchrony index improved nitrogen utilisation and digestibility of organic matter and neutral detergent fibre and cow productive performance and immunity status. The integration of synchrony index in a ration system would improve cow welfare and productive performance. [ABSTRACT FROM AUTHOR]

Compared to nonmodular machines, modular topologies become increasingly attractive due to their simplified manufacture process, better fault-tolerant capability, and potentially reduced material consumption. In order to maintain or even enhance the machine performance while achieving high fault-tolerant capability, novel modular, single-layer winding switched reluctance machines (SRMs) with different pole numbers are proposed, which are supplied by rectangular wave current with different conduction angles. The influences of the pole number and flux gap width between E-core segmented stators on the electromagnetic performance have been investigated in terms of self- and mutual inductances, electromagnetic torque, copper loss, iron loss, and radial force. It has been found that the modular structures with higher rotor pole numbers than stator slot numbers (12-slot/14-pole and 12-slot/16-pole SRMs) can maintain and even improve the average torque due to the nature of self and mutual inductances. In addition, the torque ripples for modular machines are significantly reduced (below 50%), so do the iron loss and radial force, leading to higher efficiency albeit with potentially lower vibration and acoustic noise. Two prototypes with 12-slot/8-pole and 12-slot/14-pole combinations have been built with both nonmodular and modular structures to validate the predictions in terms of inductances and static torques. [ABSTRACT FROM AUTHOR]

This paper adopts simple analytical modeling to investigate the contribution of air-gap field harmonics to the torque production in some three-phase, 12-slot/8-pole doubly salient synchronous reluctance machines (DSRMs) with both conventional and mutually coupled winding configurations. The air-gap flux density has been calculated based on the analytically obtained magnetomotive force and doubly salient air-gap permeance for both the double-layer and single-layer DSRMs with different winding configurations. Then, the contribution of different air-gap field harmonics to average torque and torque ripple can be investigated and validated by direct finite-element analyses. It has been found that in the DSRMs, the 10th-order harmonic in the double-layer conventional winding (DLC), the 4th-order harmonic in the double-layer mutually coupled winding (DLMC), the 7th-order harmonic in the single-layer conventional winding (SLC), and the 10th-order harmonic in the single-layer mutually coupled winding (SLMC) have the highest contribution to positive average torque and with positive influence on torque ripple reduction. However, the 2nd-order harmonic in the DLC, the 8th-order harmonic in the DLMC, the 5th-order harmonic in the SLC, and the 2nd-order harmonic in the SLMC machines mainly reduce the average torque. [ABSTRACT FROM AUTHOR]

The flux gaps in alternate stator teeth of the modular permanent-magnet machines can have a significant impact on the total magnet flux density, and hence the potential magnet reversible/irreversible demagnetization under flux weakening operations or short-circuit conditions. Such a problem has not been studied in literature and will be investigated in this paper. The influence of flux gaps on the d-axis inductance and the potential peak short-circuit current is analyzed for different slot/pole number combinations. It is found that the flux gaps will affect both d-axis inductance and open-circuit flux linkage, and hence reduce short-circuit current of machines with pole number (2p) smaller than slot number (Ns), while they will increase the short-circuit current of machines with 2p > Ns . However, the opposite phenomena can be observed for demagnetization withstand capability. For machines having 2p < Ns, the flux gaps tend to lower withstand capability, while for machines having 2p > Ns, this capability can be improved. Other parameters such as magnet thickness and temperature have also been accounted for in the demagnetization analysis. Tests have been carried out to validate the predictions of inductances and short-circuit current, as well as performance such as phase back electromotive force, cogging torque, and static torque for machines with one defective magnet, which represents the case of partially demagnetized magnets. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of conduction angles on the performances of two 3-phase 12-slot/8-pole short-pitched switched reluctance machines (SRMs): single-layer SRM with conventional winding (SL-CSRM) and single-layer SRM with mutually coupled winding (SL-MCSRM). Both unipolar and bipolar excitations are employed for the SRMs with different conduction angles such as unipolar 120° elec., unipolar 180° elec., bipolar 180° elec., bipolar 240° elec., and bipolar 360° elec. Their flux distributions, self- and mutual-flux linkages, and inductances are analyzed, and followed by a performance comparison in terms of on-load torque, average torque, torque ripple, using 2-D finite-element method. Copper loss, iron loss, and machine efficiency have also been investigated with different phase currents and rotor speeds. The predicted results show that the conduction angle of unipolar 120° elec. is the best excitation approach for the SL-CSRM at low current and also modest speed, as its double-layer (DL) counterpart. However, at high current, the higher average torque is achieved by a conduction angle of unipolar 180° elec. For the SL-MCSRM, bipolar 180° elec. conduction is the most appropriate excitation method to generate a higher average torque but lower torque ripple than others. The lower iron loss is achieved by unipolar excitation, and the SL-CSRM with unipolar 120° elec. conduction produces the highest efficiency than others at 10 \textA\mathrm{ rms} . In addition, the performances of single-layer machines have been compared with those of the established DL-SRMs with conventional and mutually coupled windings. The prototype SRMs for both SL-CSRM and SL-MCSRM have been built and tested to validate the predictions. [ABSTRACT FROM AUTHOR]

This paper comprehensively investigates the electromagnetic performance of 3-phase, 12-slot, and 8-pole switched reluctance machines (SRMs) with different winding configurations, i.e., double/single layer, short pitched (concentrated), and fully pitched (distributed). These SRMs are supplied by sinewave currents so that a conventional three-phase converter can be employed, leading to behavior which is akin to that of synchronous reluctance-type machines. Comparisons in terms of static and dynamic performances such as d- and q-axis inductances, on-load torque, torque–speed curve, and efficiency map have been carried out using two-dimensional finite-element method (2-D FEM). It is demonstrated for the given size of machine considered that for same copper loss and without heavy magnetic saturation, both single- and double-layer mutually coupled SRMs (MCSRMs) can produce higher on-load torque compared to conventional SRMs (CSRMs). Additionally, double-layer MCSRM achieved the highest efficiency compared to other counterparts. When it comes to single-layer SRMs, they are more suitable for middle-speed applications and capable of producing higher average torque while lower torque ripple than their double-layer counterparts at low phase current. Two prototype SRMs, both single layer and double layer, are built to validate the predictions. [ABSTRACT FROM PUBLISHER]

Silicon on insulator (SOI)-based transistors gated by nanogranular SiO2 proton conducting electrolytes were fabricated to mimic synapse behaviors. This SOI-based device has both top proton gate and bottom buried oxide gate. Electrical transfer properties of top proton gate show hysteresis curves different from those of bottom gate, and therefore, excitatory post-synaptic current and paired pulse facilitation (PPF) behavior of biological synapses are mimicked. Moreover, we noticed that PPF index can be effectively tuned by the spike interval applied on the top proton gate. Synaptic behaviors and functions, like short-term memory, and its properties are also experimentally demonstrated in our device. Such SOI-based electronic synapses are promising for building neuromorphic systems. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of mutual fluxes (inductances) on the resultant torque in three-phase conventional switched-reluctance machine (CSRM) and mutually coupled SRM (MCSRM) using the frozen permeability (FP) method. Under saturation conditions, the FP method allows accurately separating the torques due to self-flux and mutual flux, hence quantifying their contributions to torque generation. Then, appropriate current waveforms (unipolar or bipolar, square wave or sinewave) can be established to maximize the output torques. It is well known that the mutual torque of CSRM can be negligible. However, this paper has shown that when sinewave current is employed and under full or overload conditions, the torque will be significantly reduced due to non-negligible negative mutual torques. Different from CSRM, the self-torque and the mutual torque of MCSRM can be added if current waveform is properly chosen, e.g., sinewave currents. This can significantly boost the resultant torque. The predictions have been validated by experiments. [ABSTRACT FROM AUTHOR]

OBJECTIVE: MiR-183 acts as an oncomiR and is usually upregulated in hepatocellular cancer (HCC). This study aims to study the association between miR-183 dysregulation and multi-drug resistance (MDR). Also, how it is dysregulated in HCC cells was investigated. MATERIALS AND METHODS: The association between miR-183 and HIF-1α in HCC cell line BEL-7402 and the multidrug-resistant variant BEL-7402/5-fluorouracil (BEL-7402/5-FU) were studied using qRT-PCR and Western blot analysis. The mediators involved in feedback regulation between miR-183 and HIF-1α were further studied. Then, the effect of the miR-183-SOCS6 axis on IC50 of BEL-7402/5-FU cells to 5-FU were investigated by MTT assay. RESULTS: The expression of miR-183 and HIF-1α are positively correlated in BEL-7402 and BEL-7402/5-FU cells. IDH2 knockdown resulted in significantly increased HIF-1α expression in both BEL-7402 and BEL-7402/5-FU cells. Knockdown of SOCS6 had similar but stronger effect as miR-183 in promoting MRP2, P-gp, p-STAT3 and HIF-1α expression in BEL-7402 cells, while SOCS6 overexpression also showed similar but stronger effect as miR-183 inhibition in reducing MRP2, P-gp, p-STAT3 and HIF-1α levels in BEL-7402/5-FU cells. Both SOCS6 overexpression and miR-183 knockdown significantly increased the sensitivity of BEL-7402/5-FU cells to 5-FU. MiR-183 overexpression partly abrogated the effect of SOCS6 in enhancing 5-FU sensitivity. CONCLUSIONS: Both HIF-1α-miR-183-IDH2-HIF-1α and HIF-1α-miR-183-SOCS6-p-STAT3-HIF-1α feedback loops are involved in miR-183 upregulation in HCC cells. MiR-183 can modulate MDR of HCC cells at least partly through suppressing SOCS6. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the efficiency of autologous peripheral blood stem cell transplantation (APBSCT) to treat severe the lower limbs ischemia caused by thromboangiitis obliterans (TAO). PATIENTS AND METHODS: From April 2007 to December 2014, a total of 64 patients with TAO (80 affected limbs) received APBSCT at our hospital. The treatment effect was evaluated by subjective indicators including pains and cold sensation of the affected limbs, combined with objective indicators including claudication distance, ankle brachial index (ABI), transcutaneous oxygen pressure (TcPO2) and skin temperature. RESULTS: Five patients (with 5 affected limbs) suffered from necrosis below the middle of the leg 4 weeks after transplantation and received amputation. For the remaining 59 patients (75 affected limbs), pain and cold sensation of the affected limbs were improved with varying extent 3 months after transplantation; there were statistically significant differences in pain score and cold sensation score of the affected limbs before and after APBSCT (p<0.05). Claudication distance, ABI, TcPO2 and skin temperature were also improved. Claudication distance increased from 85.69 m±43.48 m to 36.5±9.88 mmHg, and the skin temperature of the lower limbs increased from 27.70°C±0.53°C to 33.49°C±0.60°C. All four indicators were considerably improved after APBSCT (p<0.05). Arteriography was performed for 75 affected limbs in 59 patients 6 months after transplantation and found that new collateral vessels were formed in the affected limbs. No patients were complicated by retinal hyperplasia, malignant tumors, myocardial infarction and cerebral infarction during the follow- up examinations; no patients underwent symptom aggravation during 9-48 month followup (average, 28.5 months). CONCLUSIONS: APBSCT is an easy, safe and reliable treatment for ischemia of lower limbs, especially for those with poor distal arterial outflow tract in the lower limbs that do not permit bridging. [ABSTRACT FROM AUTHOR]

This paper proposes a novel cogging torque mitigation method for modular permanent magnet (PM) machines with flux gaps in alternate stator teeth. The slot openings (SOs) of the modular PM machines are divided into two groups in a special way. By shifting the SOs of two groups in opposite directions with the same angle, the machine cogging torque can be significantly reduced. An analytical formula of the desired shift angle is derived, and can be applicable to other modular machines with different slot/pole number combinations. Meanwhile, the influence of the proposed method on phase back electromotive force (EMF) is investigated, and the three-phaseback EMF waveforms remain balanced for all slot/pole number combinations after slot shifting. Experiments based on the existing prototypes are carried out to validate the finite-element modeling. [ABSTRACT FROM PUBLISHER]

This paper proposes an analytical method that combines the superposition and the subdomain methods to predict the air-gap field distribution in permanent magnet (PM) machines with rotor eccentricity. The original machine with rotor eccentricity is divided into a number of air-gap sections along the circumferential direction. For each air-gap section, a concentric model is employed by adopting an equivalent air-gap length to predict the air-gap field using the subdomain method. The air-gap field distribution of the original model can then be synthesized from these concentric models. Consequently, the electromagnetic performance can be predicted accordingly, such as flux-linkage, back EMF, and so on. Finally, the direct finite element analysis is used to validate the efficacy of the proposed method. The proposed analytical method can be extended to other machines with different slot/pole number combinations and is particularly useful for analyzing the machines with large slot and pole numbers. [ABSTRACT FROM AUTHOR]

This paper presents a simple analytical model for two types of three-phase surface-mounted permanent magnet machines: modular and unequal tooth (UNET) width machines with different slot/pole number combinations. It is based on the slotless open-circuit air-gap flux density and the slotted air-gap relative permeance calculations. This model allows calculating the opencircuit air-gap flux density, phase flux linkage, back electromotive force, and average torque of both the modular and UNET machines. Its accuracy has been validated by the 2-D finite-element (FE) method. A flux focusing/defocusing factor has also been introduced to analyze the influence of flux gaps in alternate stator teeth of modular machines on the machine electromagnetic performances. It has been found that by properly choosing the slot/pole number combination and flux gap width, the open-circuit air-gap flux density, the winding factor, and the flux focusing effect can all be improved. As a result, the performance of the modular machine can be significantly boosted. The analytical and FE models have been validated by experiments. [ABSTRACT FROM AUTHOR]

WC-TiC reinforced TiNi-Ti2Ni dual-phase intermetallic matrix coatings were labricated on the Ti6A14V substrate by laser alloying with 70 pure Ni and 30WC powders (wt.%) and then were dealt with by laser remelting. The effects of laser remelting on microstructure of the alloyed coatings were investigated by X-ray diffraction (XRD), optical microscopy (OM). scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS). In addition, mechanical properties were also evaluated. The results indicated that the remeltcd coating became denser with the reduction in defects compared with the alloyed coating. The average microhardness of the coating had few changes after remelting, however, the fracture toughness of the coating was increased significantly by 20% to 3.15 MPa-m1/2. Moreover, wear volume and mass loss of the coating before and alter laser remelting also showed that laser remelting contributed to the improvement in wear performance. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the effects of nimotuzumab (h-R3) with cisplatin (DDP) or fluorouraci l (5-FU) on human esophageal squamous cell carcinoma (ESCC) EC1 cells. MATERIALS AND METHODS: The assignment included blank control, h-R3 alone, DDP alone, 5FU alone, h-R3 combined with DDP, and h-R3 combined with 5-FU. The cell proliferation in each group was measured by MMT method 48 h post dose. The effect on the cell cycle was determined by flow cytometry, and the effect on cell apoptosis was determined by flow cytometry and TUNEL test 48 h post dose. RESULTS: The inhibitory effect of h-R3 on the proliferation of EC1 cells was weak. The maximum inhibition rate was 10.10 ± 0.58% 48 h post dose, and the difference in the inhibition rate between the h-R3 with chemotherapeutic agents and the chemotherapeutic agent alone was not statistically significant (p > 0.05). Flow cytometry demonstrated no obvious change in the EC1 cells after h-R3 treatment (p > 0.05). Flow cytometry and TUNEL test demonstrated that the difference in the apoptosis rate between h-R3 combined with chemotherapeutic agents and blank control was not statistically significant (p > 0.05). CONCLUSIONS: h-R3 had no significant effect on human ESCC EC1 cells in vitro, with or without the combination of chemotherapeutic agents. [ABSTRACT FROM AUTHOR]

HLA-DRB1*11:143 has one nucleotide change from HLA-DRB1*11:01:01 where Aspartic Acid (70) is changed to Glycine. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The aim of this meta-analysis was to further explore whether the relapse, 5-year survival and metastasis the same or not between limb-salvage and amputation in the treatment of patients with limited stage EnnekingII pathologic fracture osteosarcoma. MATERIALS AND METHODS: An electronic search of the Medline, EMBASE and CNKI was done on October 2014. The clinical studies about amputation or limb-salvage surgery in the treatment of patients with limited stage EnnekingII pathologic fracture osteosarcoma were searched and reviewed. The effect size of relapse, 5-year survival and metastasis between the amputation and limb-salvage surgery were pooled by stata11.0 software (Stata Corporation, College Station, TX, USA, http://www.stata.com;) using random or fixed effect model. The funnel plot and Egger's line regression test were used for evaluation of publication bias. RESULTS: A total of 89 studies were identified and seven articles with 200 cases in the limb-salvage surgery group and 84 subjects in the amputation group were finally included in the meta-analysis. The pooled data indicated that no statistical different of risk for developing relapse between limb-salvage and amputation was found relative risk (RR) =1.40, 95% confidence interval (CI): 0.71-2.79, (P = 0.33). The 5-year survival rate of patients underwent limb-salvage surgery was smaller than patients received amputation RR = 1.86, 95%CI: 1.19-2.89, (P = 0.01); the metastasis rate of patients underwent limb-salvage surgery was significant decreased compared with patients received amputation RR = 0.56, 95% CI: 0.34-0.94, (P = 0.03). No publication bias was existed in this meta-analysis. CONCLUSION: Limb-salvage surgery does not increased the risk of relapse compared with amputation in the treatment of patients with limited stage EnnekingII pathologic fracture osteosarcoma. [ABSTRACT FROM AUTHOR]

This paper presents two short-circuit fault models of a hybrid excitation flux switching permanent magnet machine, i.e., excitation phase short-circuit and interturn short-circuit in excitation windings. Two-dimensional finite element (FE) method is used to calculate the major parameters, such as armature and excitation inductances, which are not only functions of rotor position, but also of armature and excitation currents. Moreover, in case of short-circuits, the variations of armature and excitation currents are often significant. This in turn leads to an important change in winding inductances. Therefore, in order to precisely predict machine performance under short-circuit conditions, the use of inductances versus rotor position and RMS currents is essential. With the obtained FE results, two MATLAB/Simulink-based models are established. Then, the previously mentioned short-circuits have been studied and their influences on electromagnetic performances, such as armature and excitation currents, speed and torque, armature and excitation copper losses, stator and rotor core iron losses, as well as permanent magnet (PM) eddy current losses are analyzed. Experiments have been carried out to validate the simulations. [ABSTRACT FROM PUBLISHER]

In order to simplify manufacture processes and improve fault-tolerant capabilities, modular electrical machines, especially the ones with segmented stators, are increasingly employed. However, flux gaps between segments are often inevitable. In this paper, to take advantage of these flux gaps to enhance the machine performance, novel modular permanent magnet machines with different slot/pole combinations have been proposed. The influence of these flux gaps on the electromagnetic performance of modular PM machines, such as winding factor, open-circuit air-gap flux densities, back-EMFs, cogging torque, on-load torque, inductances, magnetic saturation and copper losses, are comprehensively investigated and general rules have been established. It is found that for modular machines having slot number higher than pole number, the flux gaps between stator segments degrade the electromagnetic performance due to the lower winding factor and the flux defocusing effect. However, for modular machines having slot number lower than pole number, the electromagnetic performances can be significantly improved using proper flux gap width due to the higher winding factor and the flux focusing effect. The finite element results are validated by experiments using two prototype modular machines. [ABSTRACT FROM PUBLISHER]