Finite element analysis of pulse sharpening effect of gyromagnetic nonlinear transmission line based on Landau-Lifshitz-Gilbert equation.

Ferrite-loaded gyromagnetic nonlinear transmission line (GNLTL) provides a possible option to compress an input pulse to a narrower width for its remarkable sharpening effect. However, it is difficult to accurately predict the output of the GNLTL due to the complex interaction between the magnetic moment of ferrite and the bias magnetic field. In this paper, a finite element model of the GNLTL is established based on the Landau-Lifshitz-Gilbert equation to investigate the performance of the GNLTL. To validate this model, a prototype is used for experimental comparison. The result demonstrates good agreement between experiment and simulation. This paper further explores the influence of the bias magnetic field and the length of the GNLTL on the output pulse. Moreover, a method to sharpen the falling edge is proposed based on the reflection and superposition of the GNLTL output. Simulation and experimental results show its effectiveness and feasibility.

[Clinical efficacy of different waves of electroacupuncture on knee osteoarthritis and its effect on TGF-ß1 in joint fluid].

OBJECTIVE: To observe the therapeutic effects of different waves of electroacupuncture (EA) on knee osteoarthritis (KOA), and to explore the mechanism of different waves of EA on promoting cartilage repair. METHODS: Ninety- seven patients with KOA were randomly divided into a dilatational wave group (32 cases, 2 cases dropped off), a continuous wave group (32 cases, 2 cases dropped off) and a discontinuous wave group (33 cases, 3 cases dropped off). The same acupoints of Xuehai (SP 10), Liangqiu (ST 34), Dubi (ST 35) and Neixiyan (EX-LE 4) were selected in the three groups. The dilatational wave (frequency of 2 Hz/10 Hz) was used in the dilatational wave group, the continuous wave (frequency of 10 Hz) was used in the continuous wave group, and the discontinuous wave (frequency of 10 Hz) was used in the discontinuous wave group. All the needles were retained for 30 min. All the treatment was given 3 times a week (on Monday, Wednesday and Friday) for 4 weeks. Lysholm knees scoring scale (LKSS) was used to evaluate the knee joint function before and after treatment, and the content of transforming growth factor-ß1 (TGF-ß1) in the joint effusion before and after treatment was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared before treatment, the total score and each score of LKSS were increased after treatment in the three groups (all P<0.05). The improvements of total score, pain score, instability score, swelling score of LKSS in the continuous wave group and the dilatational wave group were superior to those in the discontinuous wave group (all P<0.05). The content of TGF-ß1 in the joint effusion in each group was increased after treatment (P<0.05), and the improvement in dilatational wave group was superior to thoes in the continuous wave group and the discontinuous wave group (all P<0.05). CONCLUSION: The three different waves of EA could all improve the clinical symptoms of KOA, which may promote cartilage repair by increasing TGF-ß1 content. The dilatational wave had the best overall effect, which can be used as a clinical optimal treatment.

Development of a compact high-voltage pulser for hypervelocity microparticles injector.

This paper highlights the development of a high-voltage pulser that utilizes a zero-voltage-switching (ZVS) circuit and diode split flyback transformer to produce high-voltage DC pulses for a hypervelocity microparticle injector. In our circuit, the resonant inverter of the ZVS circuit is coupled to the diode split flyback transformer to generate a voltage of 10-40 kV. A power MOSFET (IXTQ 110N10P) is placed in the circuit to switch the variable DC input power supply to get a repetitive pulse output. The frequency of the high voltage output pulse can be adjusted from DC to 500 Hz, and the rise time of the voltage is about 0.28 ms. The high-voltage pulser has been connected to a microparticle injector to undergo testing, and the ejection of microparticles has been successfully observed. Detailed simulation and experimental results of the high-voltage pulser are presented.

Field-reversed configuration formed by in-vessel θ-pinch in a tandem mirror device.

We describe a field reversed configuration (FRC) experiment featuring in-vessel θ-pinch coils and open-field-line plasmas confined in a tandem mirror. Two FRCs, formed near the west and the east mirror throats of a central cell, are ejected toward the mid-plane for colliding and merging. Each FRC consists of four groups of pulsed power supplies and four groups of coils, having diameters 35, 35, 40, and 45 cm. The rise time of the main reversal field is 7.15 µs, and the maximum voltage is 40 kV with total currents of 416 kA, corresponding to a magnetic field of 1690 G. The total capacitive stored energy is 115.2 kJ. A fast pulse gas injection system was designed and tested to inject neutral gas into the FRC formation region with controlled directions. The successful installation of the θ-pinch coils inside the vacuum vessel offers greater freedom for diagnostics and control instruments as well as preserving magnetic tandem mirror configuration. The magnetic field reversal is confirmed by internal magnetic field measurements. The plasma temperature, density, and lifetime are, respectively, ∼100 eV, ∼3.0 × 1018 m-3, and ∼300 µs for the current operating conditions.

Warm sparse-dense wave inhibits cartilage degradation in papain-induced osteoarthritis through the mitogen-activated protein kinase signaling pathway.

Cartilage degradation is an important in the pathogenesis of osteoarthritis (OA). Abnormal activation of the mitogen-activated protein kinase (MAPK) signaling pathway in chondrocytes promotes an inflammatory response, resulting in the release of chondral matrix-degrading enzymes that accelerate the degradation of cartilage. As a non-pharmaceutical and non-invasive physical therapy regimen, warm sparse-dense wave (WSDW) has been successfully used for the treatment of OA. However, it remains unclear whether WSDW inhibits cartilage degradation in OA through the MAPK signaling pathway. The present study investigated the effects of WSDW on papain-induced OA in rat knee joints. Papain-induced OA was established in rats, which were subsequently divided into a model group and three experimental groups that received a WSDW with the following ratios: WSDW=1:1, WSDW=1:2 and WSDW=2:1. After 12 weeks of treatment, cartilage degradation was evaluated by Mankin scoring of paraffin-embedded sections stained with hematoxylin and eosin. The changes in cartilage structure were observed by transmission electron microscopy, and the expressions of RAS, extracellular signal-regulated kinase (ERK), p38 and p53 were measured by reverse transcription-quantitative polymerase chain reaction and western blot analysis. WSDW was demonstrated to improve the arrangement of collagen fibers, inhibit the tidemark replication and delay cartilage degradation in papain-induced OA. The expressions of RAS, ERK, p38 and p53 in the WSDW (1:2) and (2:1) groups were significantly decreased when compared with the model group (P<0.01). Furthermore, amongst the WSDW groups, the inhibitory effects of the WSDW (1:2) group were typically greater than those of the WSDW (1:1) and (2:1) groups. The results indicate that WSDW may inhibit cartilage degradation in papain-induced OA in rat knee joints by regulating the MAPK signaling pathway.

A high voltage pulse generator based on silicon-controlled rectifier for field-reversed configuration experiment.

A high voltage pulse generator based on a silicon-controlled rectifier has been designed and implemented for a field reversed configuration experiment. A critical damping circuit is used in the generator to produce the desired pulse waveform. Depending on the load, the rise time of the output trigger signal can be less than 1 µs, and the peak amplitudes of trigger voltage and current are up to 8 kV and 85 A in a single output. The output voltage can be easily adjusted by changing the voltage on a capacitor of the generator. In addition, the generator integrates an electrically floating heater circuit so it is capable of triggering either pseudosparks (TDI-type hydrogen thyratron) or ignitrons. Details of the circuits and their implementation are described in the paper. The trigger generator has successfully controlled the discharging sequence of the pulsed power supply for a field reversed configuration experiment.

Ion cyclotron resonance heating (ICRH) systems for the Keda Mirror with AXisymmetry (KMAX).

In this paper, we describe the engineering work involved in constructing two ion cyclotron resonance heating (ICRH) systems for use in the Keda Mirror with AXisymmetry tandem mirror experiment. Because they offer an effective and robust heating method, ICRH systems have been widely used in a variety of plasma experiments. The goal of our system is to heat the hydrogen plasma contained in the central cell using the fundamental ion cyclotron frequency. Both systems can deliver a radiofrequency power of ∼120 kW with adjustable operating frequencies that are tuned to be slightly lower than their local ion cyclotron frequencies. Two types of antennas are installed in the central cell in an attempt to launch both slow and fast waves. The heating mechanism is reliant on the magnetic beach effect for slow waves.

Needle-knife therapy improves the clinical symptoms of knee osteoarthritis by inhibiting the expression of inflammatory cytokines.

Knee osteoarthritis (KOA) is a degenerative joint disease that occurs mainly in the elderly population. However, there are currently no effective treatments for treating this condition. In this study, the efficacy of needle-knife therapy, a technique of traditional Chinese medicine that has been widely used to treat KOA was investigated. Patients (n=170) with KOA were randomly divided for needle-knife therapy (treatment group) and acupuncture therapy (control group). Outcome evaluation included stiffness, pain, physiological function, overall changes, total symptom score, clinical curative effects and the concentrations of interleukin (IL)-1ß, IL-6 and tumor necrosis factor-α (TNF-α) in the synovial fluid. The trial was completed in 151 patients (233 knees) from a total of 170 patients (264 knees); the treatment group comprised 76 patients (117 knees) who completed the trial and 9 patients (14 knees) who were removed from the study, and the control group comprised 75 patients (116 knees) who completed the trial and 10 patients (17 knees) who were removed from the study. The symptom scores of KOA in stages I-IV were reduced significantly in the treatment group and those of stages I-III were decreased significantly in the control group. The effective rate of the KOA therapy in the patients of stages III and IV in the treatment group was significantly higher than that in the control group. After treatment, the decrements of IL-1ß, IL-6 and TNF-α in the treatment group were greater than those in the control group. These results showed that the use of needle-knife therapy to treat KOA effectively improved the clinical symptoms by inhibiting the expression of inflammatory cytokines.

Icariin promotes bone formation via the BMP-2/Smad4 signal transduction pathway in the hFOB 1.19 human osteoblastic cell line.

Icariin, the main active compound of the traditional Chinese medicine, Epimedium, is commonly used for the clinical treatment of osteoporosis. However, the precise molecular mechanism of the therapeutic effect of icariin has not been elucidated. The aim of this study was to examine the effect of icariin on cell viability, alkaline phosphatase (ALP) activity, the amount of calcified nodules, and to delineate the molecular mechanism of icariin-enhanced bone formation by investigating the expression of bone morphogenic protein-2 (BMP-2), Smad4, Cbfa1/Runx2, osteoprotegerin (OPG), receptor activator of nuclear factor κ-B ligand (RANKL) and the OPG/RANKL ratio in the hFOB 1.19 human osteoblastic cell line. We found that icariin significantly increased the cell viability, the activity of ALP and the amount of calcified nodules in the hFOB 1.19 cells. Furthermore, we observed that icariin upregulated the expression of BMP-2, Smad4, Cbfa1/Runx2, OPG, RANKL and the OPG/RANKL ratio. Our results indicate that icariin can modulate the process of bone formation via the BMP-2/Smad4 signal transduction pathway in hFOB 1.19 cells.

Clinical study on the treatment of knee osteoarthritis of Shen-Sui insufficiency syndrome type by electroacupuncture.

OBJECTIVE: To study the clinical effificacy of electroacupuncture (EA) on treating knee osteoarthritis (KOA) of Shen ()-Sui () insuffificiency (SSI) syndrome type. METHODS: A total of 245 patients (279 knees) of KOA-SSI were randomly assigned to two groups by lottery: 141 knees in the treatment group and 138 knees in the control group. The treatment group was managed with EA at the dominant points of Neixiyan (Ex-LE4) and Waixiyan (Ex-LE5) as well as the conjugate points of Xuanzhong (GB39) and Taixi (KI3) for 30 min, once a day, with 15 days as one course; 2 courses were applied with a 5-day interval in between. The control group was treated with intra-articular injection of 2 mL hyaluronic acid into the affected joint every 7 days for 5 times in total. The clinical effects on the patients in different stages were observed, and their symptom scores of knee and contents of cytokines, including interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), prostaglandin E(2alpha) (PGE(2alpha)) and matrix metalloproteinases-3 (MMP-3), in the knee joint fluid were measured before and after treatment. RESULTS: The study was completed in 235 patients (263 knees); four patients (7 knees) in the treatment group and six patients (9 knees) in the control group dropped out. Comparison of therapeutic effects (excellent and effective rates) between the two groups showed insignificant differences (P>0.05). Symptom scores of knee and contents of cytokines in the knee flfluid after treatment were lowered signifificantly in the patients of stage I-III in both groups (P<0.05 or P<0.01). However, the lowering of the total symptom score of knee in the patients of stage III in the treatment group was more signifificant (P<0.05). CONCLUSIONS: EA could effectively alleviate the clinical symptoms in KOA patients of stage III, showing an effect superior to that of hyaluronic acid. EA also shows action in suppressing the secretion of IL-1, IL-6, TNF-alpha, PGE(2alpha) and MMP-3 in the knee flfluid.

[Effects of time factors on acupoint sticking therapy for preventing and treating bronchial asthma].

OBJECTIVE: To observe the influence of time factors on acupoint sticking therapy for preventing and treating bronchial asthma. METHODS: Seventy-one cases were randomly divided into a dog days group (n= 30), a Sanjiu days group (n=21) and a daily days group (n=20). They were all treated with ginger moxibustion plus acupoint sticking of Chinese medicine at Dazhui (GV 14) and Feishu (BL 13) etc. This treatment was applied once at the beginning of the first dog days, the middle dog days and the last dog days respectively in the dog days group, and once at the beginning of the first nine days, the middle nine days and the last nine days in coldest days of winter respectively in the Sanjiu days group, and once every other 10 days during 30 days except the dog days or the Sanjiu days in the daily days group. Their therapeutic effects and quality of life and changes of serum level of interleukin 13 (IL-13) were observed. RESULTS: The total effective rate of the dog days group was 83.3% (25/30), the Sanjiu days group and the daily days group were 61.9% (13/21) and 65.0% (15/20) respectively, with no significant differences among three groups (all P>0.05). After treatment, there were no significant differences in quality of life and changes of serum level of IL-13 among three groups, but there were significant differences between before and after treatment (P<0.01, P<0.001). CONCLUSION: Acupoint sticking is an effective therapy for bronchial asthma. It can be practiced in the whole year for the result of this study that medicines and acupoints are the leading factors of this therapy and the time factors have no influence on therapeutic effect.

[Effect of OA kneepad on apoptosis genes Bcl-2 and p53 expression in articular cartilage cells of experimental knee osteoarthritis].

OBJECTIVE: To study the effects of kneepad on expression of Bcl-2 and p53 mRNA of chondrocyte in white rabbits with knee osteoarthritis, so as to explore and treatment mechanism of OA kneepad on apoptosis of chondrocytes of rabbits with knee osteoarthritis in molecular degree. METHODS: Forty-four Japanese healthy 6-month-old rabbits (equal male and female,the weight ranging from 2 to 2.2 kg) were used to establish knee osteoarthritis models by modified Hulth method. The rabbits were randomly divided into 6 groups: normal group, model group, control group (microwave), experimental group 1 (electricity), experimental group 2 (thermal), experimental group 3 (kneepad). Ten rabbits in the normal group were breed with conventional method; 9 rabbits in the model group were breed with conventional method after model made; 9 rabbits in the control group were treated with microwave for 30 minutes, one time daily; 9 rabbits in the experimental group 1 were treated with electricity (density wave) for 30 minutes,one time daily;8 rabbits in the experimental group 2 were treated with hot (hot soft membrane) for 30 minutes, one time daily; 9 rabbits in the experiment group 3 were treated with electrothermal (OA knee pad) for 30 minutes, one time daily. All the rabbits were treated for 16 weeks and then sacrificed. The expressions of Bcl-2 and p53 mRNA of chondrocytes in knee joint were detected by using fluorescence quantitative RT-PCR method. RESULTS: At the 16 hthek,th e OD260/OD280 value range of total RNA extracted from rabbit articular cartilage tissue in each group were all at 1.80 to 2.00,wh ich indicates high RNA purity. The p53 relative mRNA in articular cartilage cells of model group,th e control group,th e experimental group 1 ,r oup 2,gr oup 3 were overexpressed,an d Belc2 mRNA expression levels of articular cartilage cells were low expression,an d compared with the normal group there were significant differences (P < 0.01). Belc2, p53 mRNA expression in articular cartilage cells,th ere were significant differences (P < 0.01) between the control group, experimental group 1, group 2, group 3 and model group. The results between the control group, experimental group 1 ,group 2 and group 3 had significant differences (P < 0.01). CONCLUSION: OA-kneepad can up-regulate the mRNA expression of Bcl-2 as well as down-regulate the mRNA expression of p53, thereby to inhibit the apoptosis of cartilage cells and delay the degeneration of articular cartilage changes.

[Effects of shouwu-huanjing recipe on human sperm motility and fertility in vitro].

OBJECTIVE: To observe the effect of Shouwu-Huanjing Recipe(SWHJR) medicated serum on human sperm motility and fertility in vitro. METHODS: Human sperm was co-cultured with SWHJR medicated serum in vitro. Human sperm motility was evaluated by computer-assisted semen analysis(CASA). The acrosome reaction and the capability of penetrating zona-free hamster eggs were also observed. RESULTS: The co-cultured SWHJR medicated serum significantly increased the sperm motion velocity(VAP, VCL, VSL) (P < 0.01), the amplitude of lateral head movement (ALH) and the beat frequency of flagellum(BCF), the density of progressive motility sperms (P < 0.05), the acrosome reaction rate(P < 0.001), the fertilization rate(FR) and the fertilization index (FI) in sperm penetration assay(SPA) test (P < 0.01). The stimulation of SWHJR medicated serum occurred in dose-dependent manner. CONCLUSION: SWHJR can improve human sperm motility and fertility.