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In the hybrid AC/DC nano‐grid, the LLC‐type DC transformer (DCT) is widely utilized in the DC and AC bus connection system (BCS) with high frequency to improve the system power density. However, it always employs the simple open‐loop scheme for not increasing the control complexity of the nano‐grid system, which creates a big challenge on the inherent features of the DCT circuit for the energy efficiency and conversion ability. Therefore, a robust and low‐cost design approach of the LLC‐type DCT is put forward in this paper based on the specific requirements of hybrid AC/DC nano‐grid. First of all, the design challenges of the LLC‐type DCT are discussed by analyzing the functions of BCS in nano‐grid application. Then, the detailed parameter design approach is presented step‐by‐step to meet the energy efficiency and conversion requirements in the full power range. Finally, a 6 kW nano‐grid prototype is established to verify the effectiveness of the proposed design method. The results show that the designed DCT can enjoy good energy efficiency and conversion ability with simple control and hence accommodate the high‐frequency nano‐grid application. [ABSTRACT FROM AUTHOR]

Background. Inducible nitric oxide synthase (iNOS) plays a crucial role in neuroinflammation, especially microglial activity, and may potentially represent a useful biomarker of neuroinflammation. In this study, we carefully defined a strategic plan to develop iNOS-targeted molecular PET imaging using (4 ′ -amino-5 ′ ,8 ′ -difluoro-1 ′ H-spiro[piperidine-4,2 ′ -quinazolin]-1-yl)(4-fluorophenyl)methanone ([18F]FBAT) as a tracer in a mouse model of lipopolysaccharide- (LPS-) induced brain inflammation. Methods. An in vitro model, murine microglial BV2 cell line, was used to assess the uptake of [18F]FBAT in response to iNOS induction at the cellular level. In vivo whole-body dynamic PET/MR imaging was acquired in LPS-treated (5 mg/kg) and control mice. Standard uptake value (SUV), total volume of distribution ( V t ), and area under the curve (AUC) based on the [18F]FBAT PET signals were determined. The expression of iNOS was confirmed by immunohistochemistry (IHC) of brain tissues. Results. At the end of synthesis, the yield of [18F]FBAT was 2.2–3.1% (EOS), radiochemical purity was >99%, and molar radioactivity was 125–137 GBq/ μ mol. In vitro, [18F]FBAT rapidly and progressively accumulated in murine microglial BV2 cells exposed to LPS; however, [18F]FBAT accumulation was inhibited by aminoguanidine, a selective iNOS inhibitor. In vivo biodistribution studies of [18F]FBAT showed a significant increase in the liver and kidney on LPS-treated mice. At 3 h postinjection of LPS, in vivo, the [18F]FBAT accumulation ratios at 30 min post intravenous (i.v.) radiotracer injection for the whole brain, cortex, cerebellum, and brainstem were 2.16 ± 0.18 , 1.53 ± 0.25 , 1.41 ± 0.21 , and 1.90 ± 0.12 , respectively, compared to those of mice not injected with LPS. The mean area under the curve (AUC0-30min), total volume of distribution ( V t , mL/cm3), and K i (influx rate) of [18F]FBAT were 1.9 ± 0.21 - and 1.4 ± 0.22 -fold higher in the 3 h LPS group, respectively, than in the control group. In the pharmacokinetic two-compartment model, the whole brain K i of [18F]FBAT was significantly higher in mice injected with LPS compared to the control group. Aminoguanidine, selective iNOS inhibitor, pretreatment significantly reduced the AUC0-30min and V t values in LPS-induced mice. Quantitative analysis of immunohistochemically stained brain sections confirmed iNOS was preferentially upregulated in the cerebellum and cortex of mice injected with LPS. Conclusion. An automated robotic method was established for radiosynthesis of [18F]FBAT, and the preliminary in vitro and in vivo results demonstrated the feasibility of detecting iNOS activity/expression in LPS-treated neuroinflammation by noninvasive imaging with [18F]FBAT PET/MRI. [ABSTRACT FROM AUTHOR]

Background. Tension-type headache (TTH) is the most common headache disorder. Current treatments for TTH have been reported to be associated with insufficient long-term benefits and unwanted adverse events (AEs). The Chinese herbal formula Xuefu Zhuyu (XFZY) has been utilized in TTH treatment, but the evidence supporting its efficacy remains unclear. This study will evaluate the efficacy and safety of XFZY for TTH. Methods. This multicenter, double-blind, randomized, placebo-controlled trial will be undertaken in China. A total of 174 eligible participants will be randomly assigned to either an XFZY group or a placebo group (20 ml each dose, three times daily for 4 weeks) at a ratio of 1 : 1. The primary outcome is the change in mean headache intensity measured by a 10 cm visual analogue scale (VAS). Secondary outcomes include the area-under-the headache curve (AUC), headache frequency, rescue medication use, qi-stagnation and blood-stasis pattern measurement, quality of life measured by the EuroQol-5-Dimensions-5-Level (EQ-5D-5L), global evaluation of medication, and health economic indexes. Discussion. The results of the study are expected to provide evidence of high methodological and reporting quality on the efficacy and safety of XFZY for TTH. This trail is registered with ChiCTR1900026716 (registered on 19 October, 2019). [ABSTRACT FROM AUTHOR]

Objectives: Due to the shortage of donor pool, there has been a need for organs with prolonged cold ischemic time. This study aims to evaluate the short-term results of different cold ischemic times in orthotopic heart transplantation based on a single-center experience in China.Methods: We retrospectively analyzed outcomes of the heart transplant patients from 1 January 2015 to 31 December 2017. The recipient population was divided into four groups. Group 1: cold ischemic time greater than 8 hours; group 2: the cold ischemic time between 6 and 8 hours; group 3: the cold ischemic time between 4 and 6 hours; and group 4: cold ischemic time less than 4 hours. Efficacy indicators included after transplant survival, infection rate, rejection rate, and complications.Results: The four groups have similar donor and recipient baseline characteristics (P > .05). Cold ischemic time greater than 8 hours had more cardiopulmonary bypass (CPB) time (127.62 ± 50.23 minutes; P = .003), CPB-assist time (86.14 ± 36.74 minutes; P = .047), and higher intra-aortic balloon pump (IABP) usage rate postoperatively (47.36%; P = .010). Cold ischemic time greater than 8 hours witnessed a relatively higher mortality rate compared with the other three groups (P = .115, P =  .078, and P =  .114) during the 2-year follow-up. Survival rates of 1 and 2 years for the four groups were 78.95%, 87.13%, 87.32%, and 87.50% and 68.42%, 85.14%, 85.92%, and 83.93%, respectively.Conclusion: Cold ischemic time less than 8 hours can be reasonably applied to expand the heart transplantation donor pool. Cold ischemic time greater than 8 hours might result in longer CPB time, CPB-assist time, and higher IABP usage postoperatively. It might also affect the in-hospital and 2-years survival rate. [ABSTRACT FROM AUTHOR]

Abstract: Styrene–butadiene rubber (SBR) nano‐composites were prepared through mixing SBR latex with bacterial cellulose whiskers (BCWs). BCWs were extracted from the residual bacterial cellulose (BC) that was treated with acid hydrolysis. A rod‐like nanofiber structure of BCWs was observed by transmission electron microscopy and atomic force microscopy. BCWs maintained the crystal structure in BCWs/SBR nano‐composites as confirmed by X‐ray diffraction patterns. The dispersion of BCWs in SBR matrix was further detected with field emission scan electron microscope. BCWs acted as a multifunctional physical cross‐linker in the SBR matrix, the combination of BCW reinforcement and increased effective cross‐linking density of the rubber network with incorporating BCWs would cause a more effective transfer of stresses from matrix to filler. Compared with neat SBR, the tensile strength and tear strength of SBR/BCW nano‐composite with 2.5 phr (parts per hundred rubber) BCWs were increased by 319% and 182%, respectively. [ABSTRACT FROM AUTHOR]

Objective. Effect of isopropanolic Cimicifuga racemosa extract (iCR) on uterine fibroid size compared with tibolone. Method. The randomized, double-blind, controlled study in China enrolled 244 patients aged 40-60 years with menopausal symptoms (Kupperman Menopause Index ≥ 15). The participants were treated with either iCR of 40mg crude drug/day (N = 122) or tibolone 2.5mg/day (N = 122) orally for 3 months in 2004. Now, we investigated the subset of all women (N = 62) with at least one uterine fibroid at onset of treatment for the effect of iCR (N = 34) on fibroid size compared with tibolone (N = 28) by transvaginal ultrasonography. Results. The median myoma volume decreased upon iCR by as much as -30% (P = 0.016) but increased upon tibolone by +4.7%.The percentage of volume change, mean diameter change and geometricmean diameter change of the iCR group compared to tibolone were statistically significant (P = 0.016, 0.021, 0.016 respectively). Conclusion. Our results suggest that iCR (Remifemin) is a valid herbal medicinal product in patients with uterine myomas as it provides adequate relief from menopausal symptoms and inhibits growth of the myomas in contrast to tibolone. [ABSTRACT FROM AUTHOR]

Background. Evidences are accumulating that age and gender have great impact on the distribution of stroke risk factors. Such data are lacking in Chinese population. Methods. 1027 patients with first-ever ischemic stroke (IS) were recruited and divided into young adult (80 years) groups according to stroke onset ages. Vascular risk factors were collected and compared among groups. Results. Female patients were globally older than male patients at stroke onset and having higher prevalence of diabetes mellitus (DM), heart diseases, and atrial fibrillation (AF). However, females were less likely to drink heavily or smoke than males. Young patients had a much higher proportion of smoking and drinking than middle-aged and very old patients and the highest family history of hypertension, while very old patients had the highest prevalence of heart diseases and AF but lowest proportion of positive family history of vascular diseases. Hypertension and DM were equally frequent among three groups. Conclusion. Our study showed that vascular risk factors had a specific age and gender distribution pattern in Chinese IS patients. Secondary prevention strategy should emphasize on the control of different risk factors based on patient’s age and gender.