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Small nucleolar RNA (snoRNA) plays important role in various histogenesis. Whether snoRNA plays a role in adipogenesis is unknown. SNORD126 is a C/D box snoRNA. We previously demonstrated that SNORD126 promoted hepatocellular carcinoma cell growth by activating the phosphoinositide 3‐kinase–protein kinase B (Akt) pathway through upregulating fibroblast growth factor receptor 2 expression. In the present study, we found that the expression of SNORD126 was downregulated in the obesity‐related tissues in high‐fat diet‐fed rats. Overexpression of SNORD126 in 3T3‐L1 cells promoted adipocytes differentiation. SNORD126 significantly increased the expression of CCAAT/enhancer‐binding protein α, fatty acid‐binding protein 4, peroxisome proliferative‐activated receptor‐γ, and the phosphorylation of Akt and p70S6K. Overexpression of SNORD126 in human adipose‐derived stem cells stimulated adipogenesis and increased phosphorylation of Akt. Meanwhile, SNORD126 increased the messenger RNA and protein levels of cyclin D1 and cyclin‐dependent kinase 2, which promoted mitotic clonal expansion progression during the early stage of 3T3‐L1 cell differentiation. We further found that SNORD126 accelerated the growth of the groin fat pad and increased phosphorylation of Akt and p70S6K in rats. Overall, our results suggested that SNORD126 promoted adipocyte differentiation through increasing phosphorylation of Akt and p70S6K both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Grid-connected offshore wind farms are likely to cause harmonic resonances in the power system that jeopardize the safe operation of the power grid. To this end， the impact of grid-connected offshore wind farms on the transient overvoltage and harmonic resonance characteristics of the onshore power grid PCC （point of common coupling） is studied， and a harmonic resonance management scheme is proposed. Firstly， PSCAD simulation modeling is performed for a grid-connected project of offshore wind farms in Zhejiang Province. Then the transient overvoltage and harmonic resonance characteristics of the grid-connected system under different operation modes are obtained by simulation. The results show that the maximum per-unit value of PCC transient overvoltage is 2.1 p.u.， which is less than the limit value of 3.0 p.u. and meets the safety requirements. Finally， the harmonic suppression strategy of parallel connection with low impedance branch filters five times and seven times respectively at PCC that significantly weakens the harmonic amplification of PCC and reduces the total harmonic distortion rate to less than 1.5%， eliminating the second to seventh low-frequency harmonic amplification.

Background: Globally, there have been many cases of coronavirus disease 2019 (COVID-19) among medical staff; however, the main factors associated with the infection are not well understood.Aim: To identify the super-factors causing COVID-19 infection in medical staff in China.Methods: A cross-sectional study was conducted between January 1st and February 30th, 2020, in which front-line members of medical staff who took part in the care and treatment of patients with COVID-19 were enrolled. Epidemiological and demographic data between infected and uninfected groups were collected and compared. Social network analysis (SNA) was used to establish socio-metric social links between influencing factors.Findings: A total of 92 medical staff were enrolled. In all participant groups, the super-factor identified by the network was wearing a medical protective mask or surgical mask correctly (degree: 572; closeness: 25; betweenness centrality: 3.23). Touching the cheek, nose, and mouth while working was the super-factor in the infected group. This was the biggest node in the network and had the strongest influence (degree: 370; closeness: 29; betweenness centrality: 0.37). Self-protection score was the super-factor in the uninfected group but was the isolated factor in the infected group (degree: 201; closeness: 28; betweenness centrality: 5.64). For family members, the exposure history to Huanan Seafood Wholesale Market and the contact history to wild animals were two isolated nodes.Conclusion: High self-protection score was the main factor that prevented medical staff from contracting COVID-19 infection. The main factor contributing to COVID-19 infections among medical staff was touching the cheek, nose, and mouth while working. [ABSTRACT FROM AUTHOR]

Objective To summarize the experiences and perioperative complications of endovascular recanalization in chronic carotid artery occlusion (CCAO). Methods A total of 12 patients with CCAO were included from August 2018 to July 2019, who were all treated with endovascular recanalization. The occlusive site, occlusive segment, occlusive proximal stump morphology and the nature of the lesion were evaluated by multimode imaging, and perioperative complications were recorded. Results Ten patients were successfully operated, the success rate of vascular recanalization was 83.33%. Two patients had failed in surgery, including one patient with long segment artery dissection above the petrous bone segment and one patient with blunt stump. Perioperative complications occurred in 6 patients, including 3 cases of intraoperative embolus shedding, one case of intraoperative vasospasm, one case of postoperative cerebral hyperperfusion syndrome (CHS), and one case of postoperative severe hypotension. Conclusions The long segment lesion above the petrous bone segment, the shape of the stump and the nature of lesion may affect the success rate of vascular recanalization. Embolus detachment, vasospasm, CHS and hypotension are the main perioperative complications. [ABSTRACT FROM AUTHOR]

A grey box framework is applied to model ship maneuvering by using a reference model (RM) and a support vector machine (SVM) (RM-SVM). First, the nonlinear characteristics of the target ship are determined using the RM and the similarity rule. Then, the linear SVM adaptively fits the errors between acceleration variables of RM and target ship. Finally, the accelerations of the target ship are predicted using RM and linear SVM. The parameters of the RM are known and conveniently acquired, thus avoiding the modeling process. The SVM has the advantages of fast training, quick simulation, and no overfitting. Testing and validation are conducted using the ship model test data. The test case reveals the practicability of the RF-SVM based modeling method, while the validation cases confirm the generalization ability of the grey box framework. [ABSTRACT FROM AUTHOR]

Volumetric positioning error is an important index that influences the machining accuracy of five-axis machine tools. Although the available compensation methods, including hardware and software compensation, provide approaches to improve the volumetric positioning accuracy of five-axis machine tools, the cost-effect ratio of these methods is usually not acceptable for most users. Based on the volumetric error model of a five-axis machine tool and the sag error compensation function together with the table multiplication function in Siemens 840D system, a novel volumetric positioning error compensation method is proposed in this paper. The experiments show that the proposed compensation method can effectively improve the machining accuracy of the machine tool with really low cost, which shows good perspective in manufacturing industry. [ABSTRACT FROM AUTHOR]

We extend real options analysis of timberland investments to examine a combination of financial and biophysical risk effects on optimal investment strategies in the southeastern United States. Results show that, despite a slight downward drift in price, expected returns for loblolly pine management fall between entry and exit thresholds, indicating an optimal "hold" strategy. This is explained by an offsetting upward trend in biophysical productivity associated with climate changes across a range of modeled futures. Monte Carlo analysis indicates a small positive difference between entry and exit outcomes consistent with observed rates of expansion in timberland investments in the region. (JEL D81, Q23) [ABSTRACT FROM AUTHOR]

This study assessed the utility of ultrasound-guided lateral transversus abdominis plane (TAP) block combined with rectus sheath (RS) block for peritoneal dialysis catheter placement surgery. Thirty consecutive patients with end-stage renal disease scheduled to have peritoneal dialysis catheter placement received a left lateral TAP block combined with RS block performed under ultrasound guidance. The TAP and RS blocks were, respectively, conducted with 15 ml of 0.5% ropivacaine and 10 ml of 0.5% ropivacaine. Pain intensity was evaluated by verbal rating scale during operation, and the degree of patient and surgeon satisfaction was qualified by a categorical scale. Twenty-nine patients received successful blocks without any other adjuvant anesthetic drugs. One patient required rescue analgesia with lidocaine infiltration. No complications related to regional anesthesia were noted. Ultrasound-guided left lateral TAP block combined with RS block can serve as the primary anesthetic modality for peritoneal dialysis catheter placement surgery. [ABSTRACT FROM AUTHOR]

Precision design is an important approach to guarantee the accuracy of industrial robots, where error sensitivity analysis lays a vital foundation. Intuitively, if the pose error vector caused by one error component is nearly perpendicular to the sum vector that is caused by all error sources, this error component will have little influence on the accuracy of end-effector even though its norm is large. Unimportant errors may unreasonably be regarded as vital errors when their direction characteristics are ignored. In this paper, the local sensitivity index (LSI) is defined based on the projection theory of spatial vector to evaluate the contribution of an error component in a definite pose. Both the direction and norm characteristics of pose error vector are considered in the novel definition of LSI, which is quite different from the previous researches. According to the definition of expectation and variance, the average sensitivity indices (ASI) and variance sensitivity indices (VSI) of error sources are established. Finally, the precision design of a 6-DOF (degrees of freedom) industrial robot is conducted in numerical simulation based on the proposed error sensitivity analysis method. The results show that the pose accuracy of end-effector can greatly be increased by improving very few error components obtained via error sensitivity analysis. The proposed error sensitivity analysis method is quite effective, which can greatly improve precision design effects. [ABSTRACT FROM AUTHOR]

Using property-level data (1987Q1-2015Q4) from the National Council of Real Estate Investment Fiduciaries, this study examines the determinants of transaction frequency of institutional commercial timberland properties in the United States. Controlling for both macro- and microlevel factors in a logit regression, the overall financial return of the timberland market, the discrepancy between anticipated sale price and last appraisal value, the superior performance of individual timberland properties over the market average, and geographic locations are found to significantly influence timberland transaction frequency. Aggregate market outlook and growth rate of the national economy are also found to have material impacts on the likelihood of timberland sales. [ABSTRACT FROM AUTHOR]

Clinical studies have demonstrated that decreased adiponectin is associated with the development of Type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD). We focused on determining the neuroprotective effect offered by adiponectin against streptozotocin-induced brain damage in ICV-STZ rat model. We found that adiponectin supplements significantly restored the cognitive deficits in ICV-STZ rat model including shorter escape latency, more crossing times and increased time spent in the target quadrant. Adiponectin supplements also increased number of dendritic branches and mushroom percentage. In addition, adiponectin supplements attenuated tau hyperphosphorylation at multiple AD-related sites through activation of protein Ser9-phosphorylated glycogen synthase kinase-3β (Ser9-GSK-3β) with increased the Akt and PI3K activity. Our data suggest that adiponectin supplements have neuroprotective effects on the ICV-STZ rat model, which may be mediated by the activation of the PI3K/Akt/GSK-3β signaling pathway. [ABSTRACT FROM AUTHOR]

BackgroundTransition metal nitrogen doped carbon materials are promising to replace precious metal platinum-based materials as an important electrocatalyst for oxygen reduction, and have attracted extensive attention in the research fields of energy storage materials and energy conversion devices.PurposeThis study aims to develop new vanadium doped transition metal carbon materials with excellent catalytic performance, and clarify the role of the introduced of vanadium.MethodsThe vanadium doped cobalt-nitrogen-carbon catalyst was designed by two-step pyrolysis method and impregnation method. The catalytic performance of the oxygen reduction reaction (ORR) was evaluated by a three electrode system using rotating disk electrode. The morphology and microstructure of catalysts were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) was employed to examine crystal orientation structure of catalyst whilst the element types and distribution of materials was analyzed by X-ray photoelectron spectroscopy. Finally, Co K-edge and V K-edge X-ray absorption fine structure (XAFS) spectroscopy were used to determine the local atomic configuration and electronic structure.ResultsThe experimental results show that vanadium doped cobalt-nitrogen-carbon catalyst exhibits superior ORR performance than the traditional cobalt‒nitrogen‒carbon catalyst. XAFS spectra clarifies that the electronic state of cobalt is changed by the introduction of vanadium, and the catalytic performance is further enhanced.ConclusionThe performance of Co‒N‒C catalyst is regulated by the high-valence state V doping, which provides an idea for the design of high-efficiency oxygen reduction catalyst.