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Analysis on eddy motion is the essential method for understanding viscous flows. Compared with the current methods to identify the vortex, the study presents a method to investigate vortex structures based on topological analysis and nonlinear dynamics, and establishes a connection between the direction of the vortex and the real eigenvalue of the velocity gradient tensor. The study highlights the significance of the real and imaginary parts of complex eigenvalues in vortex development, wherein the real part indicates topological stability and the imaginary part represents swirling strength, contributing to get the characters of the viscous flows. [ABSTRACT FROM AUTHOR]

BACKGROUND: It is uncertain whether adjunctive thrombolysis is beneficial for patients with ST-segment--elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) within 120 minutes of presentation. This study was to determine whether in patients presenting with ST-segment--elevation myocardial infarction a single bolus recombinant staphylokinase (r-SAK) before timely PCI leads to improved patency of the infarct-related artery and reduces the infarct size. METHODS: This is an open-label, prospective, multicenter, randomized study. We enrolled patients aged 18 to 75 years who were within 12 hours of symptom onset of ST-segment--elevation myocardial infarction and expected to undergo PCI within 120 minutes. Patients were administered loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive 5 mg bolus of r-SAK or normal saline intravenously before PCI. The primary end point was Thrombolysis in Myocardial Infarction flow grade 2 to 3 or grade 3 in the infarct-related artery 60 minutes after thrombolysis. The infarct size was detected by cardiac magnetic resonance 5 days after randomization. The safety end point was major bleeding (Bleeding Academic Research Consortium ≥3) during 30-day follow-up. RESULTS: A total of 283 patients were screened from 8 centers and 200 were randomized (median age, 58.5 years; 14% female). The median symptom to thrombolysis time was 252.5 (interquartile range, 142.8-423.8) minutes and thrombolysis to coronary arteriography was 50.0 (interquartile range, 37.0-66.0) minutes. Patients randomized to r-SAK compared with normal saline more often had Thrombolysis in Myocardial Infarction flow grade 2 to 3 (69.0% versus 29.0%; P<0.001) and Thrombolysis in Myocardial Infarction flow grade 3 (51.0% versus 18.0%; P<0.001) and had smaller infarct size (21.91±10.84% versus 26.85±12.37%; P=0.016). There was no increase in major bleeding (r-SAK, 1.0% versus control, 3.0%; P=0.616). CONCLUSIONS: A single bolus r-SAK before primary PCI for ST-segment--elevation myocardial infarction improves infarctrelated artery patency and reduces infarct size without increasing major bleeding. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05023681. [ABSTRACT FROM AUTHOR]

Farrerol is a flavonoid found in plants with a wide range of pharmacological effects, including protection and enhancement of nerve cell function, as well as antioxidant and antibacterial properties, among others. Neurodegenerative diseases are irreversible neurological disorders resulting from the loss of neuronal cells in the brain and spinal cord. In this experiment, we investigated the neuroprotective and antioxidant effects of farrerol on glutamate-induced HT22 cells. Our results showed that farrerol inhibited reactive oxygen species expression, apoptosis, mitochondrial damage, and the activation of caspases 3 and 9 in HT22 cells induced by glutamate. Additionally, farrerol potentially regulated the Nrf2/heme oxygenase-1 (HO-1) signaling pathway, as it attenuated the nuclear translocation of Nrf2 and promoted the expression of HO-1. These findings suggest that farrerol has potential as a new therapeutic option The mechanism of farrerol inhibiting cell apoptosis. [ABSTRACT FROM AUTHOR]

This paper uses farm survey data from the western margin of the Corn Belt to estimate the causal effects of adopting different conservation practices--conservation tillage (CT), cover cropping (CC), and diversified crop rotation (DCR)--on perceived changes in yield, production cost, and profit among farmers in South Dakota. We use propensity score kernel matching to correct the sample selection bias induced by nonrandom adoption of different conservation practices. We find that compared with non-adopters, farmers who adopt CT and DCR are more likely to perceive an increase in profit and yield and CC adopters are less likely to perceive a production cost increase. [ABSTRACT FROM AUTHOR]

Although sexual health programming and clinical sexually transmitted infections (STIs) services have traditionally been developed through 'top-down' approaches, there is emerging evidence that participatory approaches benefit the development and implementation of such services. Although other studies have already highlighted the benefits of participation in research and implementation of clinical STIs services delivery, this narrative review focuses on how community participation in clinical STIs services delivery has been operationalised and on the various aspects of clinical STIs services delivery in which participatory processes have been implemented. A PubMed search was conducted in January 2022 using the search terms that reflected the topic of participatory processes in clinical STIs services delivery to identify relevant papers. Only peer-reviewed papers published in English were reviewed, and no timeframe was selected. After reviewing existing studies, we identified how community participation has been incorporated across stages of clinical STIs service delivery, including planning, developing, delivering, evaluating, and scaling up, as well as gaps and challenges faced in implementing such approaches. This review highlighted how a wide range of participatory processes characterised by varying depths of participation have been used in the above processes. Challenges such as funding, socio-cultural barriers, technical barriers and the digital divide, issues of quality assurance, and standardising the measurement of participation remain, which may impede the uptake of participatory processes in clinical STIs services. [ABSTRACT FROM AUTHOR]

One of the main challenges in microgrid system energy management is dealing with uncertainties such as the power output from renewable energy sources. The classic two-stage robust optimization (C-TSRO) method was proposed to cope with these uncertainties. However, this method is oriented to the worst-case scenario and is therefore somewhat conservative. In this study, focusing on the energy management of a typical island microgrid and considering uncertainties such as the power output of renewable energy sources and the power demand of loads, an expected-scenario-oriented two-stage robust optimization (E-TSRO) method is proposed to alleviate the conservative tendency of the C-TSRO method, because the E-TSRO method chooses to optimize the system cost according to the expected scenario instead, while ensuring the feasibility of the first-stage variables for all possible scenarios, including the worst case. According to the structural characteristics of the proposed model based on the E-TSRO method, a column-and-constraint generation (C&CG) algorithm is utilized to solve the proposed model. Finally, the effectiveness of the E-TSRO model and the solution algorithm are analyzed and validated through a series of experiments, and thus obtaining some important conclusions, i.e., the economic efficiency of system operation can be improved at about 6.7% in comparison with the C-TSRO. [ABSTRACT FROM AUTHOR]

Using bivariate ordered logit models, we investigate factors that determine farmers' perceptions of cover-crop profitability and likelihood of future usage in the climate transition zone of the Northern Great Plains. Our results indicate that approximately 40% of long-term (10+ years) users perceived a profit increase of more than 5%. Additionally, future adoption decisions are positively affected by environment-oriented attitudes and negatively affected by prioritizing short-term profitability. More efforts can be directed toward educational programs that enhance understanding of the short- versus long-term economic benefits of cover crops. [ABSTRACT FROM AUTHOR]

SnS2-sensitized TiO2 nanotubes were fabricated via anodic oxidation and a successive ionic layer adsorption and reaction process. The prepared SnS2/TiO2 composites were used as photoanodes, and the corresponding photocathodic protection effect on 304 stainless steel was studied. The effect of the number of adsorbed SnS2 molecules on the photocatalytic protection conferred by the SnS2/TiO2 composites was also analyzed. The morphology and composition of the samples were analyzed by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The optical absorption properties of the samples were analyzed by ultraviolet-visible diffuse reflectance spectroscopy. The electrochemical properties of the SnS2/TiO2 composites were characterized in terms of their open circuit potential, the photocurrent density, the electrochemical impedance spectrum and the current-voltage curve and used to analyze the photocatalytic protection effect. The results show that the SnS2/TiO2 composite exhibits higher visible light absorption and offers more photocathodic protection than pure TiO2 nanotubes. Using SnS2/TiO2(6C) as a photoanode reduces the potential of 304 stainless steel to -730 mV. [ABSTRACT FROM AUTHOR]

The flow instability always varies within different compressors; however, even in one compressor, there may be still multiple various unsteady modes. To study the triggering mechanism for these unsteady modes, a detailed experimental research on an industrial centrifugal compressor with variable vaned diffuser is performed from design point to surge. The multiposition dynamic pressure measurement is conducted during the whole valve-adjusting process. The characteristics of pressure fields under some specific operating conditions are focused on, especially the prestall, stall and surge conditions. According to the collected data, the features of different unsteady modes can be obtained, such as the surge pattern and the propagation direction of stall cells. In addition, when the diffuser vane setting angle (DVA) is adjusted, the core factors to trigger total instability will change. To better complement the experimental analysis, a multipassage numerical simulation is carried out. Based on the agreement of performance curves obtained by the two methods, the flow field characteristics in the prestall state shown in the simulation results are indeed a good complement to the dynamic experimental analysis. Meanwhile, with the help of dynamic mode decomposition (DMD) method, a few low-frequency unsteady structures are extracted from the transient numerical result over a long time, which correlate with the experimental result. Through detailed analysis, an insight into the different unsteady modes in a centrifugal compressor with variable vaned diffuser is obtained. [ABSTRACT FROM AUTHOR]

By making adoption decisions on soil conservation practices, agricultural producers play a key role in reversing unintended consequences caused by soil degradation. This paper studies two soil conservation practices--diversified crop rotation (DCR) and integrated cropping and livestock system (ICLS)--using survey data collected from Nebraska, South Dakota, and North Dakota producers. We estimate a bivariate probit model to identify factors affecting adoption decisions. Farmers' requirements for monetary incentives and values on soil health were found to be important determinants of adoption behavior. Geographic location matters, as North Dakota had the highest DCR adoption rate yet the lowest ICLS adoption rate. [ABSTRACT FROM AUTHOR]

This study evaluated the wettability of commercial vinyl polysiloxane impression materials by measuring contact angles on horizontal and non-horizontal surfaces using artificial saliva. Three light bodies (Affinis [Affi], Silagum [Sila] and Variotime [Vario-LB]) and one extra light body (Viriotime [Vario-ELB]) were prepared with flat surfaces. Static and dynamic contact angles were measured using the sessile drop method as a function of time. Contact angle hysteresis was the value of advancing contact angle minus receding contact angle. The results indicated that all materials were classified as hydrophilic materials. Vario-ELB and Affi showed better initial wettability than the other two materials. Vario-ELB showed more hydrophilic properties and was more vulnerable to changes in the intraoral environment compared to Affi, Sila and Vario-LB. These results suggest that measuring the time-dependent dynamic contact angle on the inclined surface can provide effective information regarding the wettability of impression materials to evaluate their clinical performance. [ABSTRACT FROM AUTHOR]

SnS/TiO2 nanocomposites were successfully fabricated by a successive ionic layer adsorption and reaction process. The effect of the material concentration on the preparation of the SnS/TiO2 composite films was discussed. TiO2 nanotube arrays co-sensitized with SnS nanoparticles were used as a photoanode to provide photoelectric protection for 304 stainless steel. The crystalline structures, morphology, and optical absorption property of the samples were measured by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, and X-ray photoelectron spectroscopy. The photogenerated cathodic protection performance was characterized by measuring the open-circuit potential and photocurrent density response, and by performing electrochemical impedance spectroscopy. The results indicate that the SnS/TiO2 composites have high light absorption and photo-electrochemical properties under visible light irradiation. The SnS/TiO2 composite prepared at the optimal concentration could shift the corrosion potential of the 304 stainless steel form -280 mV to -720 mV. [ABSTRACT FROM AUTHOR]

In-orbit geometric calibration is a key technology for improving the geometric positioning accuracy of satellites. Conventional geometric calibration, which uses high-accuracy ground control data to accurately calibrate the orientation parameters of a satellite, heavily relies on the control data of the calibration fields and may not be applicable in emergencies where urgent and accurate positioning is needed. The constant calibration of satellites is also difficult owing to the lack of permanent calibration fields. This paper presents a geometric cross-calibration method for the rapid and accurate calibration of satellites. The conjugate points from the multitemporal images of one satellite or multi-satellite images are first automatically extracted; then, the interior orientation parameters of the satellite requiring calibration can be precisely recovered according to the positioning consistency constraint of the conjugate points. In contrast to the conventional method, the proposed method can accurately calibrate the orientation parameters without using high-accuracy control data of the calibration fields. Therefore, the proposed method aids in the constant calibration of satellites to ensure the positioning accuracy, even without sufficient permanent calibration fields. The multitemporal images of the Yaogan-4 satellite and the images of the ZY3-01 and ZY02C satellites were considered for verifying this method. Finally, accuracies of approximately 0.7 and 0.6 pixels were achieved by the proposed and conventional methods, respectively. The difference between the two methods was only approximately 0.1 pixels, demonstrating that the proposed method can achieve a calibration accuracy as high as that achieved by the conventional method, even without the use of high-accuracy control data. [ABSTRACT FROM AUTHOR]

This study developed carbon nanotube coatings for the dentin surface and investigated the bonding strength and the in vitro antibacterial properties of carbon nanotube-coated dentin. Single-walled carbon nanotubes and multi-walled carbon nanotubes were first modified and then characterized using Fourier-transform infrared spectroscopy, scanning electron microscope, and transmission electron microscopy. Second, dentin samples were coated using either single-walled carbon nanotubes or multi-walled carbon nanotubes and observed under a scanning electron microscope. Then, the shear bonding strength and antibacterial properties of the dentin samples were tested. The results showed that both modified single-walled carbon nanotubes and multi-walled carbon nanotubes formed a stable coating on the dentin surface without affecting the shear bonding strength. Moreover, the antibacterial properties of the single-walled carbon nanotube-coated samples was obviously superior to those of the multi-walled carbon nanotubecoated samples. Consequently, single-walled carbon nanotube coating may be an antibacterial agent for potential application in the dental bonding field. [ABSTRACT FROM AUTHOR]

Background and objective Segmentectomy can retains more healthy lung tissue than lobectomy, but it remains controversial in oncology for early stage lung cancer. The aim of this study is to discuss the problems of video-assisted thoracic surgery (VATS) segmentectomy in early stage lung cancer, by analyzing the clinical and pathological data of 35 cases and reviewing the literature. Methods There were 35 patients who received segmentectomy by complete video-assisted thoracic surgery, from May 2013 to July 2017, in single operation group in the Third Hospital of Peking University. We analyzed the patient's clinical and pathological data, intraoperative and postoperative complications, lymph node number and metastasis its situation, and compared postoperative pathology and preoperative computed tomography (CT) imaging type. In 35 cases of segmentectomy, there were 11 males and 24 females, with an average age of 57.7 years old. The lesions located in the right upper lobe were 8 cases, in the right lower lobe were 8 cases, in the left upper lobe were 13 cases, in the left lower lobe were 6 cases. The mean maximum diameter of CT imaging was 12.7 mm, and the largest diameter of hilar and mediastinal lymph nodes was less than 10 mm. 23 of them were ground glass predominating and 12 were solid components predominating. Results All 35 cases were successfully completed VATS anatomical segmentectomy. The average operation time was 153 minutes, the amount of bleeding was 51 mL. There were 10 cases of air leakage after operation, all of which were not more than 3 days. There was contralateral atelectasis in 1 case, chylothorax in 1 case. The average length of hospitalization was 6.1 days. There was no other complications outpatient related to surgery, in 30 days after discharge. The pathological changes were as follow, 2 cases of metastatic tumor, 8 cases of benign lung disease and 25 cases of primary lung cancer. In the 25 cases of primary lung cancer, there were 14 cases of invasive lung adenocarcinoma (7 cases were groundglassopacity (GGO) predominating in CT imaging), 4 cases of micro-invasive adenocarcinoma (3 cases were GGO predominating in CT imaging), 6 cases of adenocarcinoma in situ (all were pure GGO in CT imaging), 1 case of lung squamous cell carcinoma (mainly composed of solid in CT imaging). An average of 7.2 lymph nodes were removed in 25 cases of lung cancer, and all lymph nodes had no metastasis. Conclusion VATS anatomical segmentectomy is technically safe and reliable, and the indications for lung cancer need to be strictly controlled. Its advantages still need to be confirmed by prospective randomized controlled trials. [ABSTRACT FROM AUTHOR]

This paper proposes an accurate channel calibration algorithm for ground moving target indication (GMTI) applications with multichannel synthetic aperture radar (SAR) systems. The proposed algorithm is developed in a statistical fashion, and a useful tool called correlation analysis is employed, which measures the coherence between two channels by means of correlation coefficient. Based on correlation analysis theory, an optimum solution to a very general channel calibration problem is obtained, for which only the knowledge of the first two moments of the channel output signals is assumed and no other distributional assumptions are made. The proposed optimum solution represents a generic solution to the general channel calibration problem, which leads to a simple implementation form and needs no iterative operation. The performance test results show that the proposed correlation analysis processing algorithm is an effective way of calibrating the channels. [ABSTRACT FROM AUTHOR]

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Objective: To investigate whether early low intensity ergometer aerobic training could produce sustained benefits on activities of daily living for severely impaired stroke survivors. Methods: Forty-two severely impaired stroke hemiplegia were enrolled. They were all six weeks within stroke onset and younger than sixty. The affected lower limb was three or less on the 7 point Chedoke-Mcmaster Stroke Assessment scale. Both groups participated in 6 week rehabilitation training program. Only subjects in the intervention group received low intensity ergometer aerobic training three times every week. Primary outcome variables were Barthel Index (BI), Functional Ambulation Category scale (FAC) and Frenchay Activities Index (FAI). Secondary outcome were Fugl-Meyer motor score, exercise test duration and peak heart rate. Results: Patients in the experimental group tolerated aerobic training well. When compared with the control group, patients in the experimental group showed significant improvements in BI and FAC immediately after intervention, and higher FAC and FAI scores one year later (P < 0.05). Conclusions: Preliminary findings suggest early low intensity ergometer aerobic training may have sustained effect on activities of daily living for severely impaired non-elderly stroke survivors. [ABSTRACT FROM AUTHOR]

To investigate the effects of the iron chelatordeferoxamine (DFA) on inhibition formicroglia activation and protection of secondary nerve injury after intracerebral hemorrhage (ICH) in rats. The rats were randomly divided into sham operation group, ICH group and DFA treatment group. The collagenase was used to prepare ICH model of basal gangliain rats and lh after the beginning of the operation, the intraperitoneal injection with DFA was arranged every 12 h and for a total of 7d. The changes of Iron ion concentration were measured at perihematomaat different time points after the medicine was given. 0X42 immunohistochemical staining observed microglia change at perihematoma. ELISA method determined the changes of IL-1(3 and TNF-a content of brain tissue. Neurological deficit scores and Nissl staining were used to observe the situation of neurological function and neuronal loss of rats after DFA treatment. 1 d After the start of ICH, the concentration of iron in perihematoma was significantly higher than that of animalsin shamoperated group and could sustain for28 d. At the same time, the quantities of local microglial cells were significantly increased. After applying DFA, the concentration of iron ions in the brain tissue around the hematoma was significantly reduced, so did the number of microglial cells and activation of neurotoxic cytokines (IL-lp and TNF-a content) secreted by microglial cells was significantly reduced. At the same time, the loss of neurons in the tissue around of the hematoma was significantly reduced and neurological deficit scores were significantly reduced, iron ions which were sustainedly released by hematoma after ICH can activate the local microglia and cause secondary brain injury. DFA curb excessive activation of microglia and reduce neuronal death of ICH by means of clearinf away iron ions of brain tissue surrounding the hematoma, thus improve secondary neurological dysfunction. [ABSTRACT FROM AUTHOR]