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The external cavity spectral beam combining (SBC) of a laser diode (LD) with fibre output was researched. We proposed a method to achieve dense wavelength beam combination based on a LD with fibre output. In order to demonstrate our conception, two LDs with pigtail output, centre wavelength of 976 nm, and about 45% of electric-to-optical (E-O) conversion efficiency was employed to achieve spectral beam combination. This method demonstrated the feasibility of closed loop SBC of LD with pigtail. The free running spectrum, single laser spectrum with locked wavelength, spectrum after combination were measured. The feedback efficiency of external cavity was about 1.55% when the transmission of cavity output mirror was about 30%. The combination power of 1.63 W was obtained, the optical-to-optical (O-to-O) transferable efficiency was about 25%. The deterioration factor beam quality was about 1.2×, meanwhile, the efficiency loss of SBC and the reason of deterioration of beam quality were analysed. According to the results, we designed the kilowatt level LD with fibre output, the O-O efficiency can be increased to about 70%. [ABSTRACT FROM AUTHOR]

Background: Regenerative techniques are increasingly applied in endodontic surgery, but different materials used in regenerative techniques may have varying impacts on wound healing. Objectives: This study evaluated the effects of different regenerative techniques and materials on the outcome of endodontic surgery. Participants: patients with persistent periapical lesions, treated with root‐end surgery. Control: endodontic surgery without the use of regenerative techniques/materials. Intervention: endodontic surgery with the use of regenerative techniques/materials. Outcome: combined clinical and radiographic results. Methods: PubMed, Web of Science, Embase, SinoMed and the CENTRAL Cochrane were searched up to 10th July 2020, followed by a manual search. Detailed eligibility criteria were applied. Cochrane's risk‐of‐bias tool 2.0 was used to assess the risk of bias of the eligible studies. Meta‐analysis was conducted using RevMan software. Subgroup analyses were performed based on the regenerative materials used in endodontic surgery. Results: Eleven eligible randomized controlled trials (RCTs) were included in the meta‐analysis: two had a low risk of overall bias, and nine had some concerns of overall bias. Generally, the use of regenerative techniques significantly improved the outcome of endodontic surgery (risk ratio [RR]: 0.42; 95% confidence interval [CI], 0.26–0.68; P < 0.001). On subgroup analysis, the use of expanded polytetrafluoroethylene (e‐PTFE) membranes alone had no added benefits (RR: 2.00; 95% CI, 0.22–18.33; P = 0.54). The application of collagen membranes or autologous platelet concentrates (APCs) alone was associated with a trend for better outcomes (RR: 0.51; 95% CI, 0.20–1.25; P = 0.14) (RR: 0.55; 95% CI, 0.18–1.71; P = 0.30). The combined use of collagen membranes and bovine‐derived hydroxyapatite significantly improved the outcome (RR: 0.35; 95% CI, 0.17–0.75; P = 0.007). Discussion: This systematic review evaluated the effects of collagen membranes, e‐PTFE membranes, APCs and bone grafting materials, providing detailed information about the risks and benefits of using each regenerative technique/material or its combination in endodontic surgery. Conclusions: Regenerative techniques improve periapical lesion healing after endodontic surgery. The combined use of collagen membranes and bovine‐derived hydroxyapatite may be beneficial as an adjunct to endodontic surgery. In contrast, the positive efficacy of e‐PTFE membranes or APCs alone remains doubtful. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to explore the atypical imaging findings of the novel coronavirus pneumonia (COVID-19) and its evolution. MATERIALS AND METHODS: The atypical imaging data of ten patients in our hospital who tested positive for COVID-19 were analyzed retrospectively, and the distribution, morphology, and image evolution of the lesions were analyzed. High-resolution computed tomography (HRCT) was performed in all cases, and the imaging features were analyzed and summarized by two senior radiologists. RESULTS: Of these ten patients, three were male, and seven were female. The age of these patients ranged from 21-53 years, with an average age of 36.3 ± 3.6. The first symptom was fever in nine cases and dry cough in one case. A total of 17 lesions were detected in these ten patients. Five patients had a single lesion, and five patients had multiple lesions, for a total of 12 lesions. Ten lesions (58.82%) were located in the inferior lobe of the right lung, four lesions (23.53%) in the left inferior lobe, two lesions (11.76%) in the left upper lobe, and one lesion (5.88%) in the right middle lobe. Among the five single lesions, two were solid lesions, two were mixed ground-glass lesions, and one was a pure ground-glass lesion. Among the 12 multiple lesions, eight were solid lesions, two were mixed ground-glass lesions, and two were pure ground-glass lesions. Atypical manifestations in image signs: five lesions (29.41%) had single solid and sub-solid nodules, and four lesions (23.53%) had cavitary nodules. Typical manifestation (the presence of "white lung"): three lesions (17.65%) had an air bronchogram, two lesions (11.76%) had crazy-paving signs, two lesions (11.76%) had vascular thickening, and one lesion (5.88%) had halo signs. At reexamination 2-6 days later, 15 lesions (88.24%) had enlarged or increased, and two lesions (11.76%) had decreased or absorbed. CONCLUSIONS: Patients with COVID-19 may have atypical imaging findings. Radiologists should improve their understanding of the novel coronavirus pneumonia to avoid any missed diagnoses. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Diabetic nephropathy (DN), as the most common and serious diabetic microvascular complication, has become the first cause of end-stage renal disease (ESRD) in many countries and regions. However, the pathogenesis of renal fibrosis during the development of DN remains unknown. MATERIALS AND METHODS: The expression levels of miR-192 and early growth response factor 1 (Egr1) were determined by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and Western blotting in the renal tissues of Otsuka-Long-Evans-Tokushima-Fatty (OLETF) and Long-Evans-Tokushima-Otsuka (LETO) rats. The diabetic kidney environment was simulated by a high-sugar medium. The expression levels of miR-192 and Egr1 were further measured in the HK-2 cell line. Egr1 was verified as a potential target of miR-192 by using bioinformatics analysis and luciferase activity assay. The expression level of Egr1 was determined by overexpressing and knocking down the expression of miR-192. In addition, Western blotting was used to determine changes in Transforming growth factor-beta 1 (TGF-β1) and fibronectin (FN). RESULTS: Compared with the kidney tissue of LETO rats, the expression of miR-192 was decreased in OLETF rats, whereas the expression of Egr1 was increased. We found the same phenomenon in the HK-2 cell line cultured in the high-glucose medium. Next, miR-192 can act on Egr1 through 3'-UTR to reduce the expression of Egr1 verified by luciferase assay. In addition, the expression levels of TGF-β1 and FN changed significantly, as the expression level of Egr1 increased or decreased. CONCLUSIONS: MiR-192 causes degradation of TGF-β1 and FN through targeting Egr1 and affects the progression of TIF and even DN. [ABSTRACT FROM AUTHOR]

Aims To investigate the incidence rates and trends in Type 1 diabetes in children and adolescents aged 0-19 years in the registered Zhejiang population over the period 2007-2013 by age, sex and calendar year. Methods In total, 611 individuals with newly diagnosed Type 1 diabetes were identified from 30 districts in Zhejiang province over the study period. Annual incidence and 95% confidence intervals ( CI) by age group and sex were calculated per 100 000 person-years. Trends in diabetes incidence and the associations of age and sex with Type 1 diabetes were assessed using Poisson regression models. Results The mean annual age-standardized incidence of diabetes was 2.02/100 000 person-years (95% CI: 1.92-2.12), with an average annual increase of 12.0% (95% CI: 7.6-16.6%) over the study period. The risk for Type 1 diabetes in girls was estimated to be 1.25 (95% CI: 1.07-1.47) times higher than that in boys. Compared with those aged 0-4 years, the 5-9, 10-14 and 15-19 years age groups were at significantly greater risk, with adjusting incidence rate ratios of 3.54, 6.58 and 5.39, respectively. The mean age at diagnosis decreased significantly from 12.85 years in 2007 to 11.21 years in 2013. A steep rise in diabetes incidence was observed in the under 5 years age group, which showed the greatest increase at 33.61%. Conclusions The incidence of diabetes in Zhejiang was relatively low, although rapidly rising trends have been found in recent years, particularly in younger children. Further monitoring and research are urgently required to better understand possible environmental risk factors and formulate preventive strategies. [ABSTRACT FROM AUTHOR]

This paper describes the experimental work on the tests of nine concrete-filled square and rectangular hollow structural section (HSS) columns subjected to axial load, uniaxial bending or biaxial bending. The experimental results suggest that the overall buckling appears accompanying with local buckling near the mid-height of column. Good agreement was found between the semi-sine wave shape and the experimental deflection shape. It is found that the cross-section remains plane before the specimen reached its load-carrying capacity. Also, the experimental results are compared with the values calculated from the AISC-LRFD, EC4 and CECS design codes, which shows that all codes provide safe bearing capacities. Compared with columns subjected to an axial load or uniaxial bending, the calculated capacities of column subjected to biaxial bending are more conservative. Among these three design codes, the capacities based on the EC4 design code yield results which are the closest to the experimental ones. The results calculated from the AISC-LRFD design code are the most conservative. [ABSTRACT FROM AUTHOR]

Cocktail recipes containing Psoralea corylifolia seeds (PCS) are used to empirically treat Parkinson disease. A PCS isolate Δ3,2-hydroxybakuchiol (BU) can inhibit dopamine uptake in dopamine transporter (DAT) transfected Chinese hamster ovary (CHO) cells, and dopamine reuptake blockade may provide an alternative approach for ameliorating parkinsonism. Here, we assessed the potential dopaminergic neuroprotective, and antiparkinsonian-like activity of BU. BU sample size was increased by using a scale-up extraction paradigm. Pharmacologically, BU significantly protected SK-N-SH cells from 1-methyl-4-phenylpyridinium (MPP+) insult, produced striking inhibitory actions on dopamine/norepinephrine uptake and WIN35,428 binding in synaptosomes on in vivo administration, and significantly preventing poor performance on rotarod and dopaminergic loss in substantia nigra in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mice. BU acts by protecting dopaminergic neurons from MPP+ injury and preventing against MPTP-induced behavioral and histological lesions in the Parkinson’s disease (PD) model, possibly by inhibiting monoamine transporters. These findings suggest that BU could be meaningful in PD treatment. [ABSTRACT FROM AUTHOR]

In this paper, a novel platform technology for integrating radio-frequency microelectromechanical systems (RF MEMS) and CMOS on a printed circuit board (PCB) is demonstrated. An RF-MEMS switch is constructed on top of a CMOS IC wafer. The stacked structure is subsequently transferred onto a PCB substrate (i.e., FR-4) by thermal compressive bonding, mechanical grinding, and wet removal of bulk silicon. The measurement of the fabricated RF-MEMS switch on the FR-4 substrate shows promising results. It has an insertion loss of 0.25 dB at 20 GHz and an isolation of 25 dB at 20 GHz. At the same time, the performance of CMOS is not degraded during the integration process; the drain current in the p-MOS transistor remained unchanged, whereas that in the n-MOS transistor showed a slight improvement after transfer. This technology is very useful for compact RF system on PCB material with low power consumption and high performance for wearable, wireless, and implantable device applications. [ABSTRACT FROM AUTHOR]

This letter reports on a device layer transfer (based on thermal bonding and grinding backside Si) process and device characteristics of Si MOSFETs on a flexible substrate, focusing mainly on the mechanical bendability of the device and resistance to fatigue. The results demonstrated a well-optimized bonding process, as indicated by the nearly indiscernible performance difference (e.g., subthreshold slope, Vth, and Idsat) before and after the bonding of Si with the flexible substrate. The device characteristics indicate excellent bendability of Si MOSFETs on flexible substrate (e.g., for radius tested down to ±72 mm) and good immunity to fatigue (e.g., negligible performance drift tested up to 103 bending cycles with a radius of ±126 mm). Results suggest the feasibility of this approach in achieving high-performance MOSFETs for applications in performance-sensitive and flexible electronics. [ABSTRACT FROM AUTHOR]