7,299 research outputs found

    Parameter-tuning Networks: Experiments and Active Walk Model

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    The tuning process of a large apparatus of many components could be represented and quantified by constructing parameter-tuning networks. The experimental tuning of the ion source of the neutral beam injector of HT-7 Tokamak is presented as an example. Stretched-exponential cumulative degree distributions are found in the parameter-tuning networks. An active walk model with eight walkers is constructed. Each active walker is a particle moving with friction in an energy landscape; the landscape is modified by the collective action of all the walkers. Numerical simulations show that the parameter-tuning networks generated by the model also give stretched exponential functions, in good agreement with experiments. Our methods provide a new way and a new insight to understand the action of humans in the parameter-tuning of experimental processes, is helpful for experimental research and other optimization problems.Comment: 4 pages, 5 figure

    Can Sodium Abundances of A-Type Stars Be Reliably Determined from Na I 5890/5896 Lines?

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    An extensive non-LTE abundance analysis based on Na I 5890/5896 doublet lines was carried out for a large unbiased sample of ~120 A-type main-sequence stars (including 23 Hyades stars) covering a wide v_e sin i range of ~10--300 km/s, with an aim to examine whether the Na abundances in such A dwarfs can be reliably established from these strong Na I D lines. The resulting abundances ([Na/H]_{58}), which were obtained by applying the T_eff-dependent microturbulent velocities of \xi ~2--4 km/s with a peak at T_eff ~ 8000 K (typical for A stars), turned out generally negative with a large diversity (from ~-1 to ~0), while showing a sign of v_e sin i-dependence (decreasing toward higher rotation). However, the reality of this apparently subsolar trend is very questionable, since these [Na/H]_{58} are systematically lower by ~0.3--0.6 dex than more reliable [Na/H]_{61} (derived from weak Na I 6154/6161 lines for sharp-line stars). Considering the large \xi-sensitivity of the abundances derived from these saturated Na I D lines, we regard that [Na/H]_{58} must have been erroneously underestimated, suspecting that the conventional \xi values are improperly too large at least for such strong high-forming Na I 5890/5896 lines, presumably due to the depth-dependence of \xi decreasing with height. The nature of atmospheric turbulent velocity field in mid-to-late A stars would have to be more investigated before we can determine reliable sodium abundances from these strong resonance D lines.Comment: 14 pages, 8 figures, accepted for publication in Publ. Astron. Soc. Japan, Vol. 61, No. 5 (2009

    Characteristics of R134a/R410A Cascade Heat Pump and Optimization

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    Single stage air source heat pump has been widely used around the world. However, it has some drawback, for example, deteriorated heating capacity and COP in cold ambient temperature. To overcome these disadvantages, cascade cycle has been suggested and shows better performance at low ambient temperature. Cascade cycle has smaller compression ratio at each cycle and shows higher compression efficiency compared to that of single stage cycle. Intermediate pressure is most critical parameter which decides the system performance. There have been many research studies about cascade heat pump system using NH3/CO2 and C3H8/CO2 as refrigerants at high and low stage, respectively. Most studies conducted on system optimization, finding the optimal intermediate pressure. However, little information has given about the experimental optimization results. In this study, AWHP (air to water heat pump), which is composed by two single stage cycle, was studied experimentally. AWHP high and low cycle adopts R134a and R410A as refrigerants, respectively, because critical temperature of R134a is higher than R410A. Since there are two single stage cycles, each cycle has a different compression ratio. In this research, by introducing numerical analysis, system optimization was studied. Characteristics of cascade cycle with respect to each compressor have been also studied. Experiment was conducted with various operating conditions; ambient temperature, water inlet temperature

    利培酮合并舒眠胶囊治疗精神分裂症的疗效及对患者糖、脂代谢的影响

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    Objective: To explore the curative effect and influence on glucose and lipid metabolism of risperidone with Shu Mian capsules in patients with schizophrenia .Methods: 128patients with chronic schizophrenia were randomly divided into the combined group (crisperidone combined with shu mian capsules group) and the single group (risperidone group ), each group was assessed the positive and negative syndrome scale (PANSS),the body mass index (BMI ) was measured and the blood glucose and blood lipid were detected before treatment and after 2,4,8 weekends respectively. After 4,8 weeks ,both the two groups were assessed by Wesconsin card sorting test ( WCST) curative effect and their cognitive function was evaluated .Results: The reacting time in the two groups were of no significantly difference , but compared with condition before treatment, cognitive function of the patients with schizophrenia was improved and their level of total cholesterol was significantly increased (P < 0.05) in the combined group. BMI, blood glucose and blood lipid were significantly increased in single group after 8weeks’ treatment (P < 0.05 or P < 0.01). Conclusion: Shu Mian capsules can lower negative symptoms and improve cognitive function of schizophrenia ,and the dverse reactions is mild. With therapeutic dose range, risperidone in combined group or single group can make equal reacting time, curative effect and affecting blood lipid metabolism in patients with schizophrenia. Single group shows more obvious influence on blood sugat and blood fat metabolismcan.目的  探讨利培酮合并舒眠胶囊治疗慢性精神分裂症的疗效及对患者糖、脂代谢的影响。方法  128例精神分裂症患者采用系统随机分为联合组(利培酮合并舒眠胶囊组)和单用组(利培酮组)。每组各64例分别于治疗前及治疗2、4、8周末采用阳性与阴性症状量表(PANSS)进行评分,并检测体质量指数(BMI)、血糖及血脂;4、8周末评价认知能力及疗效。结果  联合组和单用组起效时间比较差异无统计学意义;联合组能部分改善精神分裂症患者的认知能力,与治疗前相比8周未联合组总胆固醇明显增高(P<0.05);单用组BMI、血糖、总胆固醇和甘油三酯明显增高(P<0.05 或P<0.01)。结论  舒眠胶囊对精神分裂症阴性症状和认知功能有一定改善作用,不良反应轻微。利培酮治疗精神分裂症的剂量范围内联合组和单用组起效时间相当,但均可影响脂代谢;单用组对血糖、血脂代谢的影响更明显。 

    The Rhizome Mixture of Anemarrhena asphodeloides

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    We investigated the effect of DWac on the gut microbiota composition in mice with 2,3,6-trinitrobenzenesulfonic acid- (TNBS-) induced colitis. Treatment with DWac restored TNBS-disturbed gut microbiota composition and attenuated TNBS-induced colitis. Moreover, we examined the effect of DWac in mice with mesalazine-resistant colitis (MRC). Intrarectal injection of TNBS in MRC mice caused severe colitis, as well as colon shortening, edema, and increased myeloperoxidase activity. Treatment with mesalazine (30 mg/kg) did not attenuate TNBS-induced colitis in MRC mice, whereas treatment with DWac (30 mg/kg) significantly attenuated TNBS-induced colitis. Moreover, treatment with the mixture of mesalazine (15 mg/kg) and DWac (15 mg/kg) additively attenuated colitis in MRC mice. Treatment with DWac and its mixture with mesalazine inhibited TNBS-induced activation of NF-κB and expression of M1 macrophage markers but increased TNBS-suppressed expression of M2 macrophage markers. Furthermore, these inhibited TNBS-induced T-bet, RORγt, TNF-α, and IL-17 expression but increased TNBS-suppressed Foxp3 and IL-10 expression. However, Th2 cell differentiation and GATA3 and IL-5 expression were not affected. These findings suggest that DWac can ameliorate MRC by increasing the polarization of M2 macrophage and correcting the disturbance of gut microbiota and Th1/Th17/Treg, as well as additively attenuating MRC along with mesalazine
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