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Multi-hole probes can simultaneously measure the velocity and direction of a flow field, obtain the distribution of the flow field in a three-dimensional space, and obtain the vortex information in the flow field. Moreover, a multi-hole probe needs to be calibrated while in use; therefore, a three-coordinate, multi-directional rotatable testing system, which can measure the flow field at any position and at any angle, was designed herein. A hemispherical seven-hole probe was calibrated with this test system, and the flow field around cylinders of different diameters was measured to obtain the pressure distribution and vortex shedding frequency. Furthermore, the designed test system’s ability to perform a multi-angle and multi-azimuth testing during the calibration of a multi-hole probe was verified. Simultaneously, through data mining of the multi-hole probe, vortices were measured, and periodic vortices were detected.

Aiming at the capture and conversion of multidirection wave energy, a multifreedom direct-drive wave-energy converter (WEC) based on a parallel mechanism is studied. The dynamic model of WEC was conducted based on force analysis and hydrodynamic theory, and the inverse kinematic solutions of each branch chain of the mechanism were obtained following the space vector method. Furthermore, the kinetics response of the linear generator branch chain was obtained. Moreover, the influence on the capture efficiency of the device’s geometric structure scale was investigated under different sea conditions. To evaluate the performance of the WEC, a linear generator model was simulated and analyzed by COMSOL Multiphysics. A laboratory prototype was manufactured. The test results indicated that the multifreedom device can achieve better power conversion performance than traditional single degree of freedom (DOF) devices. This study provides ideas for the design and development of large multi-DOF wave-energy-conversion devices.

Objective To evaluate the predictive value of fasting blood glucose (FBG) on unfavourable outcomes and mortality in diabetes mellitus (DM) patients after acute ischaemic stroke (AIS).Study design A hospital-based observational cohort study was conducted. Clinical data, including sex, age, body mass index, vascular risk factors and systolic/diastolic blood pressure, were routinely collected. National Institutes of Health Stroke Scale score was used to assess stroke severity on admission. FBG was determined on the first day after fasting for at least 8 hours. The modified Rankin Scale was used to assess functional outcome at 90 days: 3–6, unfavourable outcome and 6, death.Setting Renmin Hospital of Wuhan University, Wuhan, China.Participants Patients who had AIS with DM, who were consecutively admitted within 24 hours of onset from January 2018 to June 2019.Results For the 568 patients, the median age was 65 years (IQR, 55–74 years). There were 377 (66.4%) men. The median FBG values were 7.37 mmol/L (IQR, 5.99–10.10 mmol/L), and the median glycated haemoglobin (HbA1c) values were 6.6 (IQR, 5.8–8.3). Multivariable logistic and Cox regression analysis of confounding factors showed that FBG at the time of admission was an independent predictor of unfavourable outcome (OR, 1.25 (1.14–1.37); p

To provide the general information on corneal transplantation (CT) in China, China Cornea Society designed a questionnaire on CT from 2014 to 2018 and entrusted it to 31 committee members for implementation of the survey nationwide. This article presents the results of the survey and compares the indicators used in the survey and those in the annual statistical report released by the Eye Bank Association of America (EBAA). The number of corneal transplantations completed by the 64 hospitals from 2014 to 2018 was respectively 5377, 6394, 7595, 8270 and 8980, totally 36,616 (22,959 male and 13,657 female). The five largest hospitals by the number of corneal transplantations completed 15,994 surgeries in total, accounting for 43.68% of all the surgeries performed in the 64 hospitals. The most common indication for corneal transplantations was corneal leukoma (7683, 20.98%), followed by bacterial keratitis (4209, 11.49%), corneal dystrophies (4189, 11.44%), keratoconus (3578, 9.77%) and corneal perforation (2839, 7.75%). The main surgical techniques were penetrating keratoplasty (PK) (19,896, 54.34%), anterior lamellar keratoplasty (ALK) (13,869, 37.88%). The proportion of PK decreased from 57.97% in 2014 to 52.88% in 2018 while the proportion of ALK increased from 36.04% in 2014 to 37.92% in 2018. The geographical distribution of keratoplasties performed in China is unbalanced. PK and ALK were the main techniques of CT and corneal leukoma, bacterial keratitis and corneal dystrophies were the main indications for CT in China.

The dynamic positioning system of unmanned underwater vehicles (UUVs) is a complex and large-scale system mainly due to the nonlinear dynamics, uncertainty in model parameters, and external disturbances. With the aid of the bio-inspired computing (BIC) method, the designed three-dimensional (3D) spatial positioning system is used for enlarging communication constraints and increasing signal coordination processing. With the growing of measurement scales, the issue of the networked high-precision positioning has been developed rapidly. Then, an information fusion estimation approach is presented for the distributed networked systems with data random transmission time delays and lost and disordered packets. To reduce the communication burden, an adaptive signal selection scheme is employed to reorganize the measurement sequence, and the parameter uncertainties as well as cross-correlated noise are used to describe the uncertain disturbances. Moreover, a reoptimal weighted fusion state estimation is designed to alleviate the information redundancy and maintain higher measurement accuracy. An illustrative example obtained from the 3D spatial positioning system is given to validate the effectiveness of the proposed method.

Background: Depression is a disease that seriously threatens the quality of human life. To explore the effect of gentiopicroside on depression, this study investigated the therapeutic effect of gentiopicroside on corticosterone-induced depressionin vivo and in vitro by using metabolomic methods. Methods: A total of 36 rats were randomly assigned to three groups: a normal group, model group (depression), and treatment group (depression + gentiopicroside). Corticosterone was administrated to induce depression-like model rats. Morris water maze test was used to validated the behavior performance. The hippocampus of rats was obtained for metabolomic detection. Metabolites that were differentially expressed between the groups were extracted for Heatmap, Go, and pathway enrichment analyses. Finally, neuronal cells were cultured and examined to validated the effect of gentiopicroside. Results: Corticosterone injured rats learning capacity, and decreased the levels of 5-HT, and reversed by gentiopicroside delivery. Metabolites obtained from the hippocampus of rats in the three groups were subjected to a principal component analysis (PCA). Go and pathway enrichment analyses revealed the involvement of sphingolipid metabolism et al. Gentiopicroside could inhibit apoptosis caused by corticosterone, and also decrease neuronal cell proliferation and BDNF levels in vitro. Arachidonic acid (ARA) reversed the protective effect of gentiopicroside on neuronal cells. Conclusion: These findings suggest that gentiopicroside reduces apoptosis and increases the proliferation of hippocampus cells in depressed animals by regulating metabolites. Moreover, our study provides a new basis for the clinical treatment of depression and demonstrates the potential efficacy of gentiopicroside in this area of pathology.

Saccades result in remapping the neural representation of a target object as well as its attentional modulation. Here the authors show that the trans-saccadic attentional shift is precisely synchronized with the saccade resulting in optimal maintenance of the locus of spatial attention.

Controlled fabrication of few-atoms supported catalysts is a major challenge in the synthesis of nanomaterials. Here, the authors show a bottom-up approach to precisely synthesize platinum dimers supported on graphene, which display higher catalytic activity and stability than single atoms and nanoparticles.

The role of oxygen vacancies in carbon dioxide reduction remains somewhat unclear. Here, the authors fabricate vacancy-rich and vacancy-poor Co3O4single-unit-cell layers, and demonstrate by X-ray absorption and DFT that the material is a promising platform for mechanistic studies of carbon dioxide reduction.

The frequent forest fires become a serious threat to the performance of transmission lines’ external insulation, therefore, researches on the breakdown characteristics under flame conditions is of great significance for the transmission lines' construction and safe operation. In order to study the breakdown characteristics of the gap under forest fire, the discharge tests of conductor-plane gap were carried out by the simulation forest fire experiment platform here, and typical vegetation causing the line tripping out easily were selected to simulate the forest fire. The influences of combustion features such as flame temperature, height, conductivity, and heat release rate were analysed too. The results show that the effect of different types of vegetation flame on breakdown characteristics of gap is obviously different, especially under the fir branches flame, the average breakdown voltage gradient drops to 10% of that of the pure air gap. The flame temperature has a minimal impact on the gap breakdown characteristics, while the conductivity has a significant influence on the insulation strength of the gap.

Ultrathin metal layers can be highly active carbon dioxide electroreduction catalysts but may also be prone to oxidation. Here, the authors report the fabrication of reactive tin quantum nanosheets confined in graphene and demonstrate their enhanced electrocatalytic activity and stability.

Rotation detection is widely applied in industries. The current commonly used rotation detection system adopts a split structure, which requires stringent installation requirements and is difficult to miniaturize. This paper proposes a single-piece self-powered non-contact sensor with an interdigital sensitive layer to detect the rotation of objects. The electric field generated between a polyurethane (PU) film and a polytetrafluoroethylene (PTFE) film is utilized for perceiving the rotation. The surface of the PU film is subjected to wet etching with sulfuric acid to increase the surface area and charge density. Through finite element analysis and experimental testing, the effects of the areas of the sensitive films as well as the horizontal and vertical distances between them on the output voltage are analyzed. Tests are performed on adjustable-speed motors, human arms, and robotic arms. The results show that the sensor can detect the speed, the transient process of rotation, and the swing angle. The proposed rotation sensor has broad application prospects in the fields of mechanical automation, robotics, and Internet of Things (IoT).

Adsorption of ethylene on palladium, a key step in various catalytic reactions, may result in a variety of surface-adsorbed species and formation of palladium carbides, especially under industrially relevant pressures and temperatures. Therefore, the application of both surface and bulk sensitive techniques under reaction conditions is important for a comprehensive understanding of ethylene interaction with Pd-catalyst. In this work, we apply in situ X-ray absorption spectroscopy, X-ray diffraction and infrared spectroscopy to follow the evolution of the bulk and surface structure of an industrial catalysts consisting of 2.6 nm supported palladium nanoparticles upon exposure to ethylene under atmospheric pressure at 50 °C. Experimental results were complemented by ab initio simulations of atomic structure, X-ray absorption spectra and vibrational spectra. The adsorbed ethylene was shown to dehydrogenate to C2H3, C2H2 and C2H species, and to finally decompose to palladium carbide. Thus, this study reveals the evolution pathway of ethylene on industrial Pd-catalyst under atmospheric pressure at moderate temperatures, and provides a conceptual framework for the experimental and theoretical investigation of palladium-based systems, in which both surface and bulk structures exhibit a dynamic nature under reaction conditions.

ObjectivesA growing literature suggests that circulating cholesterol levels have been associated with Parkinson’s disease (PD). In this study, we investigated a possible causal basis for the cholesterol-PD link.MethodsFasting plasma cholesterol levels were obtained from 91 PD and 70 age- and gender-matched controls from an NINDS PD Biomarkers Program cohort at the Pennsylvania State University College of Medicine. Based on the literature, genetic polymorphisms in selected cholesterol management genes (APOE, LDLR, LRP1, and LRPAP1) were chosen as confounding variables because they may influence both cholesterol levels and PD risk. First, the marginal structure model was applied, where the associations of total- and LDL-cholesterol levels with genetic polymorphisms, statin usage, and smoking history were estimated using linear regression. Then, potential causal influences of total- and LDL-cholesterol on PD occurrence were investigated using a generalized propensity score approach in the second step.ResultsBoth statins (p 0.19). Based on propensity score methods, lower total- and LDL-cholesterol were significantly linked to PD (p

Maintaining attention at a task-relevant spatial location while making eye-movements necessitates a rapid, saccade-synchronized shift of attentional modulation from the neuronal population representing the task-relevant location before the saccade to the one representing it after the saccade. Currently, the precise time at which spatial attention becomes fully allocated to the task-relevant location after the saccade remains unclear. Using a fine-grained temporal analysis of human peri-saccadic detection performance in an attention task, we show that spatial attention is fully available at the task-relevant location within 30 milliseconds after the saccade. Subjects tracked the attentional target veridically throughout our task: i.e. they almost never responded to non-target stimuli. Spatial attention and saccadic processing therefore co-ordinate well to ensure that relevant locations are attentionally enhanced soon after the beginning of each eye fixation.

We experience a visually stable world despite frequent retinal image displacements induced by eye, head, and body movements. The neural mechanisms underlying this remain unclear. One mechanism that may contribute is transsaccadic remapping, in which the responses of some neurons in various attentional, oculomotor, and visual brain areas appear to anticipate the consequences of saccades. The functional role of transsaccadic remapping is actively debated, and many of its key properties remain unknown. Here, recording from two monkeys trained to make a saccade while directing attention to one of two spatial locations, we show that neurons in the middle temporal area (MT), a key locus in the motion-processing pathway of humans and macaques, show a form of transsaccadic remapping called a memory trace. The memory trace in MT neurons is enhanced by the allocation of top-down spatial attention. Our data provide the first demonstration, to our knowledge, of the influence of top-down attention on the memory trace anywhere in the brain. We find evidence only for a small and transient effect of motion direction on the memory trace (and in only one of two monkeys), arguing against a role for MT in the theoretically critical yet empirically contentious phenomenon of spatiotopic feature-comparison and adaptation transfer across saccades. Our data support the hypothesis that transsaccadic remapping represents the shift of attentional pointers in a retinotopic map, so that relevant locations can be tracked and rapidly processed across saccades. Our results resolve important issues concerning the perisaccadic representation of visual stimuli in the dorsal stream and demonstrate a significant role for top-down attention in modulating this representation.

AIM: To investigate the preliminary clinical observation of excimer laser phototherapeutic keratectomy(PTK)assisted by anterior segment optical coherence tomography(OCT)in the treatment of non Ⅱ type granular corneal dystrophy. METHODS: A retrospective case series were studied. Totally 8 patients(12 eyes)who were diagnosed as granular corneal dystrophy underwent PTK from April 2011 to January 2013 in our hospital. All patients were excluded from the Ⅱ type granular corneal dystrophy(Avellino corneal dystrophy)by the Avellino corneal dystrophy rapid diagnostic kit and underwent preoperative anterior segment OCT examination, so as to determine the lesion morphology and depth, and used to guide the setting of PTK parameters. They were followed up for the complications after operation, postoperative recurrence, the recovery of visual acuity. RESULTS: All patients were followed up for 6-12mo, average 9mo after operation. All patients' best corrected visual acuity were significantly improved, superficial corneal opacity lesions were effectively removed, and the corneal opacity recurrence or serious Haze were not found during the follow-up period after operation. CONCLUSION: In patients with non type Ⅱ granular corneal dystrophy, PTK assisted by anterior segment OCT can be accurate, effective removal of corneal lesions, obtain good effect after operation.

Homocysteine (Hcy) is regarded as a risk factor for hypertension, but research on the causal relationship between Hcy and hypertension is limited. In the present study, we prospectively tracked the blood pressure progression of a normotensive population with different Hcy levels over a 2-year period. The incidence of hypertension with increasing Hcy quartiles produced an approximately U-shaped curve, with significance in males. Compared with the third quartile, the risk of hypertension in the first and second quartiles was increased by 1.55 (95% confidence interval [CI] 1.154-2.081) fold and 1.501 (95% CI 1.119-2.013) fold, respectively, with the increase being more significant in males. In conclusion, Hcy is related to hypertension incidence with the results approximating an U-shaped curve. Low Hcy levels might also increase the risk of hypertension.