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BackgroundTherapeutic hypothermia improves outcomes in experimental stroke models, especially after ischemia-reperfusion injury. In recent years, the safety and efficacy of hypothermia combining thrombolysis or mechanical thrombectomy have attracted widespread attention. The primary objective of the study was to evaluate the effectiveness and safety of hypothermia by combining reperfusion therapy in acute ischemic stroke patients.MethodsA systematic search was performed in PubMed, EMBASE, Cochrane Library, and the Clinical Trial Registries on articles published until May 2024. The full-text articles were thoroughly reviewed, and relevant information regarding study characteristics and outcomes was extracted. Mantel–Haenszel (M–H) random-effects model was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI). In addition, subgroup analyses were performed focusing on the different hypothermia modalities and duration.ResultsAfter screening 2,265 articles, 10 studies were included in the present analysis with a total sample size of 785. Forest plots of clinical outcomes were as follows: modified Rankin Scale (mRS) ≤2 at 3 months (RR = 1.28, 95% CI 1.01–1.61, p = 0.04), mortality within 3 months (RR = 0.95, 95% CI 0.69–1.29, p = 0.73), total complications (RR = 1.02, 95% CI 0.89–1.16, p = 0.77) and pneumonia (RR = 1.35, 95% CI 0.76–2.40, p = 0.31). Subgroup analyses indicated a mild protective effect of selective cerebral hypothermia; however, the difference in mortality between the hypothermia and control groups was not statistically significant (RR = 0.88, 95% CI 0.57–1.35, p = 0.55). Patients undergoing hypothermia for 24–48 h experienced a higher rate of overall complications (RR = 1.37, 95% CI 1.01–1.86, p = 0.04) and pneumonia (RR = 2.84, 95% CI 1.05–7.66, p = 0.04).ConclusionThe preliminary evidence supports the safety and feasibility of hypothermia combined with reperfusion therapy, which should be further investigated in randomized controlled studies.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42024556625. more...

Abstract Background and objectives Early neurological deterioration (END) post-intravenous thrombolysis significantly impacts the long-term prognosis of stroke patients. This study aimed to establish a rapid risk prediction model for unexplained END following intravenous thrombolysis. Methods This prospective study consecutively enrolled patients with acute ischemic stroke treated with recombinant tissue plasminogen activator intravenous thrombolysis at the Department of Neurology, Third People’s Hospital of Hubei Province, and Yangluo Hospital District between June 2019 and December 2022. Unexplained END was defined as an increase of ≥ 4 points in the National Institutes of Health Stroke Scale (NIHSS) score between admission and 24 h. A nomogram was developed and assessed by calculating the area under the receiver operating characteristic curve (AUC-ROC). The calibration was assessed using the Hosmer–Lemeshow test. Results A total of 211 patients (130 males and 110 patients aged more...

Air conditioning load has become a crucial demand response resource in power systems. However, due to its diversity in types and decentralized integration, the dispatch center faces challenges in directly accessing its aggregated power and conducting scheduling control, limiting the full potential of its response. To address this issue, this paper proposes a dual-layer control framework that combines multiple types of resources, considering the aggregation response potential of air conditioning load, and integrates precise control into the scheduling process. In the day-ahead scheduling layer, an approximate aggregation model is used to determine the aggregated power of air conditioning load. Considering factors such as user thermal comfort, willingness, and controllability, an evaluation model for air conditioning load aggregation response potential is established. This model, combined with the response characteristics of fundamental flexible loads, constitutes a unified scheduling model, effectively leveraging the potential of various demand-side resources in system regulation. In the intra-day control layer, to tackle the power drop phenomenon in air conditioning groups during load reduction and temperature control strategy execution, a variable-state queuing model is introduced. By introducing preparation time, heterogeneous air conditioning clusters are grouped for controlled operation, ensuring that air conditioning load follows the scheduling plan. This enhances control precision and mitigates the impact of power drops on system operation. Lastly, based on simulation analysis of a simplified distribution network system, the results indicate that the proposed two-layer control framework can effectively harness and direct the utilization of air conditioning load response potential at the scheduling layer. At the control layer, it achieves precise control and mitigates the negative effects of power drops, demonstrating substantial practical value in engineering applications. more...

The traditional reserve planning method implicitly includes inertia in the frequency response reserve without realizing separate and accurate planning for inertia reserve, and cannot consider the risk preference of the decision maker, which leads to the homogenization of small probability extreme events. This paper refines the reserve classification system, adds inertia reserve for the first time, and proposes an inertia reserve capacity planning method considering the risk preference of decision makers. Based on the Sequential Monte Carlo method, component state models for conventional units, wind turbines, and photovoltaic units are established, and system load shedding sets are obtained through probabilistic production simulation. Based on the inertia response characteristics, the system frequency response model with multiple types of source-storage-load regulation resources is established to track the system frequency trajectory after disturbance. The minimum inertia demand is determined based on Rate of Change of Frequency (RoCoF) constraints, and then an inertia mismatch penalty model is constructed to measure the loss caused by RoCoF exceeding limits. The total cost-benefit model of inertia reserve considering risk preferences is then established, and the feasibility of the planning scheme is verified. Based on the improved IEEE RTS79 case studies, it is demonstrated that the proposed inertia reserve capacity planning method can flexibly formulate the optimal planning scheme under different risk ranges according to the decision maker’s risk preferences and the grid’s risk tolerance capability, avoiding the extreme events to be submerged in the massive and frequent occurrence of ordinary events, and effectively improving the risk response capability of the power system to extreme events, thus providing a more targeted decision basis for system planning, scheduling, and operation control. more...

Abstract Background Microleakage is a common problem that affects the quality and longevity of all-ceramic crowns. It is influenced by factors such as the resin cement, crown margin design and curing technique. However, few studies focus on the effect of different methods of removing excess resin adhesive on the microleakage of all-ceramic crowns. This study aimed to compare two methods of removing excess resin adhesive (the small brush and sickle methods) on the microleakage of all-ceramic crowns with different marginal clearances. Methods Forty extracted third molars were prepared with a 90° shoulder margin and randomly divided into four groups according to their marginal lift (30, 60, 90 or 0 μm). Procera alumina crowns were fabricated using computer-aided design/computer-aided modelling and cemented onto the teeth with 3 M RelyX Unicem (3 M Company, United States) resin cement. Excess resin cement was removed by either the small brush or the sickle scalpel method. The marginal adaptation was observed with a digital microscope. After thermal cycling of the teeth, microleakage was assessed using the dye penetration test under a stereomicroscope. The Mann–Whitney U test and Kruskal–Wallis H test were used to compare the microleakage scores among different groups. Results The small-brush group showed significantly better marginal adaptation and lower microleakage scores than the sickle group (p 0.05). Conclusion The small-brush method was more effective than the sickle scalpel method in reducing the microleakage of all-ceramic crowns with different marginal clearances. This method can improve the marginal adaptation and sealability of all-ceramic crowns, thus preventing secondary caries and other complications. more...

Land supply in China is planned by governments, and the supply ratios of various types of land are in relatively rigid administrative control. This paper constructs a DSGE model to study the relationship between land supply marketization in China and economic fluctuations. Moreover, this paper evaluates the social welfare gains from land marketization. We document that the government’s land planning constraint impacts consumption and social welfare through the land price and final output, causing resource misallocation losses in aggregate investment and output. Quantitatively, the optimal upper limit of industrial land supply is about 40% to achieve the maximum social welfare. This paper stresses the necessity of revitalizing China’s land market, and simultaneously speeding up the marketization of collectively operated construction land. more...

Abstract With the introduction of dual carbon targets, clean energy is connected to the grid on a large scale, and the stochastic and volatility of its output further affects the stable operation of the new power system. Meanwhile, in order to solve the problem that it is difficult to take into account the participation of clean energy in market‐oriented trading and complete consumption in the construction of power market, the new type of power system source–load balance dispatching model considering the market of clean energy and cross‐section stabilization is proposed. Firstly, a clean energy market price competition model based on the market clearing mechanism is proposed to realize the alternative consumption of clean energy. Secondly, considering the section security of inter‐system power transmission, a new power system source‐load balance two‐level optimization model is established by considering the cross‐section power rate and real‐time trading of clean energy market. Finally, the advantages of the model in enhancing the high proportion of clean energy consumption, rationally clearing the clean energy market and reducing the cross‐section load ratio of the contact line are verified through simulation. more...

ObjectiveTo investigate the safety and efficacy of selective intraarterial hypothermia combined with mechanical thrombectomy in the treatment of acute cerebral infarction based on microcatheter technology.MethodsA total of 142 patients with anterior circulation large vessel occlusion were randomly assigned to the hypothermic treatment group (test group) and the conventional treatment group (control group). National Institutes of Health Stroke Scale (NIHSS) scores, postoperative infarct volume, the 90-day good prognosis rate (modified Rankin Scale (mRS) score ≤ 2 points), and the mortality rate of the two groups were compared and analyzed. Blood specimens were collected from patients before and after treatment. Serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-6 (IL-6), IL-10, and RNA-binding motif protein 3 (RBM3) were measured.ResultsThe 7-day postoperative cerebral infarct volume [(63.7 ± 22.1) ml vs. (88.5 ± 20.8) ml] and NIHSS scores at postoperative Days 1, 7, and 14 [(6.8 ± 3.8) points vs. (8.2 ± 3.5) points; (2.6 ± 1.6) points vs. (4.0 ± 1.8) points; (2.0 ± 1.2) points vs. (3.5 ± 2.1) points] in the test group were significantly lower than those in the control group. The good prognosis rate at 90 days postoperatively (54.9 vs. 35.2%, P = 0.018) was significantly higher in the test group than in the control group. The 90-day mortality rate was not statistically significant (7.0 vs. 8.5%, P = 0.754). Immediately after surgery and 1 day after surgery, SOD, IL-10, and RBM3 levels in the test group were relatively higher than those in the control group, and the differences were statistically significant. Immediately after surgery and 1 day after surgery, MDA and IL-6 levels in the test group were relatively reduced compared with those in the control group, and the differences were statistically significant (P < 0.05). In the test group, RBM3 was positively correlated with SOD and IL-10.ConclusionMechanical thrombectomy combined with intraarterial cold saline perfusion is a safe and effective measure for the treatment of acute cerebral infarction. Postoperative NIHSS scores and infarct volumes were significantly improved with this strategy compared with simple mechanical thrombectomy, and the 90-day good prognosis rate was improved. The mechanism by which this treatment exerts its cerebral protective effect may be by inhibiting the transformation of the ischaemic penumbra of the infarct core area, scavenging some oxygen free radicals, reducing inflammatory injury to cells after acute infarction and ischaemia–reperfusion, and promoting RBM3 production in cells. more...

Using data of China’s listed companies from 2000 to 2016, we employ a staggered difference-in-difference (DID) approach to identify the causal effects of CEO turnover on corporate innovation. First, we find that listed companies with CEO turnover experienced an average increase of 9.5% in the quantity of innovation and 8.9% in innovation quality after the change. The dynamic effect test supports the parallel trend condition, and the placebo test rules out the nonrandom selection issue. Second, the heterogeneity tests show that CEO turnover plays a more prominent role in promoting innovation for listed firms with CEO duality, high financial constraints, and in high-tech industries. Third, CEO turnover affects corporate innovation by driving top management team reorganization and promoting R&D input. This paper has important implications for the understanding of the role of CEO turnover in companies’ innovation, as well as for strategy formulation and implementation. more...

Nitrous oxide (N2O) is not only recognized as a potent greenhouse gas, but it is also used in industry as a clean energy source. In this study, different electrode materials of carbon felt and graphite were equipped in the ΔnosZ P. aeruginosa/microbial electrolysis cell (MEC) systems to explore the optimization mechanism for long-term N2O recovery during incineration leachate treatment. The carbon felt group showed a better performance in N2O recovery across 45 days of operation. The N2O conversion efficiency was above 80% and the proportion of N2O in biogas accounted for 80.6% in the carbon felt group. qRT-PCR analysis was conducted to evaluate the expression of genes involved in denitrification (norB) and electroactivity (phzG, phzM, and phzH) of ΔnosZ P. aeruginosa. The results showed a significant upregulation in the suspended biomass (day 21) and the electron-attached biomass (day 45) from the carbon felt-equipped reactor, which was highly related to the opportunity of biomass exposed to the phenazine derivatives. By the carbon felt optimization in the system, 82.6% of the Pseudomonas genus survived after 45 days of operation. These results indicate that the carbon felt electrode has a more sustainable performance for N2O recovery in the ΔnosZ P. aeruginosa/MEC system. more...

The wide-spectrum integrated imaging method can simultaneously obtain the spectral information of different spectral bands of the same target, which is conducive to the realization of the high-precision detection of target characteristics, and can simultaneously obtain more comprehensive elements such as the structure, shape, and microphysical parameters of the cloud. However, for stray light, the same surface has different characteristics at different wavelengths, and a wider spectral band means more complex and diverse sources of stray light, which renders the analysis and suppression of stray light more difficult. In this work, according to the characteristics of the visible-to-terahertz integrated optical system design scheme, the influence of material surface treatment on stray light was studied; the stray light analysis and optimization of the whole link of light transmission were carried out. For the sources of stray light in different channels, targeted suppression measures such as front baffle, field stop, special structure baffle, and reflective inner baffle were adopted. The simulation results indicate that when the off-axis field of view was greater than 10°. The point source transmittance (PST) of the terahertz channel is on the order of 10−4, the visible and infrared channels are less than 10−5, and the final terahertz PST was on the order of 10−8, while visible and infrared channels were lower than 10−11. Here, we present a method for stray light suppression based on conventional surface treatments for broadband imaging systems. more...

With the popularization of intravenous thrombolysis, more and more people use intravenous thrombolysis to treat related diseases, but problems also arise. There are still a considerable number of patients with early disease after thrombolytic therapy not only not significantly improving, but also progressing, that is, early neurological deterioration (END). In view of this problem, the prediction of END after intravenous thrombolysis becomes very important. With the development of medical technology, research on the prediction of END after intravenous thrombolysis has gradually been carried out. Effective prediction is of great significance for the prevention and treatment of END after intravenous thrombolysis. This article aimed to carry out a meta-analysis of the predictive role of END after intravenous thrombolysis. Through an informed analysis of all studies of this type in this field, this article determines a method for predicting END after intravenous thrombolysis. The actual effect of its role is revealed in this paper, and its purpose is to promote the development of this field. This article addresses the same type of study on the predictive role of neurological deterioration after intravenous thrombolysis. The article performs test and meta-analysis of its role by conditionally searching for literature studies. It is explained using the relevant theoretical formulas. The analysis results show that the prediction of END after intravenous thrombolysis in this paper can effectively help make a preliminary judgment on the possible later neurological deterioration. Although there is an error between the predicted curve and the actual curve, the difference between the two is between 1% and 5%. It can basically effectively predict the occurrence of END. Therefore, the prediction of END after intravenous thrombolysis has a very large preventive effect on the END after intravenous thrombolysis. more...

The rapid expansion of rubber plantations in Xishuangbanna, China, has severely decreased rubber prices in the last several years. The income loss and other adverse environmental impacts have brought livelihood challenges and opportunities to develop and adopt more diversified and environmental-friendly income-generating activities (IGAs). To better understand the constraints and opportunities for smallholder rubber farmers to sustain or improve their livelihoods, this study investigates which IGAs are applied by local farmers and the factors that determine their adoption, using the sustainable livelihood framework as the theoretical guideline. The qualitative approach is applied using semi-structured interviews and thematic analysis. Five directions of changes in IGAs (i.e., intercropping, other cash crops, livestock raising for marketing, part-time job, and land renting) are identified, and local farmers are categorized into three groups (i.e., rejective, affirmative, and hesitate groups) based on their attitudes towards these IGAs. The results reveal that the main adoption motivations of certain IGAs are closely related to price shock, economic return, information, and extension service. Based on the results, suggestions are provided to enhance farmers’ motivation to make changes and improve the adoption of emerging IGAs with attention given to vulnerability contexts, livelihood assets and institutional assistance. more...

Harmonic impedance estimation and suitable evaluation index selection are the key steps of harmonic contribution evaluation. Most of the traditional harmonic impedance estimation methods are only applicable to the scenario, where the background harmonic is stable and the utility impedance is constant. However, this scenario will change in many cases due to the fluctuation of harmonic, the change of system operation mode and so on. In order to improve the estimation accuracy for harmonic impedance, a harmonic impedance estimation method is proposed in this paper based on similarity measure and ordering points to identify the clustering structure (OPTICS). The total harmonic contribution index and harmonic comprehensive contribution index are proposed based on subjective analytic hierarchy process to simplify the evaluation results. Simulation analysis and their comparison with the traditional methods reveal that the proposed harmonic impedance estimation method can reduce the influence of background harmonic voltage fluctuation and utility impedance change, making the harmonic impedance estimation result more accurate. Besides, the proposed total harmonic contribution index and harmonic comprehensive contribution index can effectively simplify contribution evaluation results, which provide a new methodology for the evaluation of harmonic contribution. more...

This study presents a new approach to the optimal placement of voltage sag monitors considering the uncertainties associated with transition resistance. The influence of transition resistance on the magnitude of voltage sags triggered by symmetrical and unsymmetrical faults is analyzed. Then the transition resistance interval set array for voltage sags is established, on the basis of which, a random vector model on voltage sag observability is proposed and related observability indices are defined in the form of conditional probability. The optimal placement model is established by taking the available number of monitors as the constraint condition and the maximum sag global observability index as the objective function. Binary particle swarm optimization (BPSO) is implemented to obtain the optimal placement results. Finally, simulation is carried out on IEEE 30-bus system, and it is shown that the proposed optimal monitor placement method is more applicable compared with the traditional MRA method. more...

Abstract The growth mechanism of GaN epitaxial layers on mechanically exfoliated graphite is explained in detail based on classic nucleation theory. The number of defects on the graphite surface can be increased via O-plasma treatment, leading to increased nucleation density on the graphite surface. The addition of elemental Al can effectively improve the nucleation rate, which can promote the formation of dense nucleation layers and the lateral growth of GaN epitaxial layers. The surface morphologies of the nucleation layers, annealed layers and epitaxial layers were characterized by field-emission scanning electron microscopy, where the evolution of the surface morphology coincided with a 3D-to-2D growth mechanism. High-resolution transmission electron microscopy was used to characterize the microstructure of GaN. Fast Fourier transform diffraction patterns showed that cubic phase (zinc-blend structure) GaN grains were obtained using conventional GaN nucleation layers, while the hexagonal phase (wurtzite structure) GaN films were formed using AlGaN nucleation layers. Our work opens new avenues for using highly oriented pyrolytic graphite as a substrate to fabricate transferable optoelectronic devices. more...

Objective: To investigate the safety and efficacy of selective intraarterial hypothermia combined with mechanical thrombectomy in the treatment of acute cerebral infarction based on microcatheter technology. Methods: A total of 142 patients with anterior circulation large vessel occlusion were randomly assigned to the hypothermic treatment group (test group) and the conventional treatment group (control group). National Institutes of Health Stroke Scale (NIHSS) scores, postoperative infarct volume, the 90-day good prognosis rate (modified Rankin Scale (mRS) score =2 points), and the mortality rate of the two groups were compared and analyzed. Blood specimens were collected from patients before and after treatment. Serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-6 (IL-6), IL-10, and RNA-binding motif protein 3 (RBM3) were measured. Results: The 7-day postoperative cerebral infarct volume [(63.7 ± 22.1) ml vs. (88.5 ± 20.8) ml] and NIHSS scores at postoperative Days 1, 7, and 14 [(6.8 ± 3.8) points vs. (8.2 ± 3.5) points; (2.6 ± 1.6) points vs. (4.0 ± 1.8) points; (2.0 ± 1.2) points vs. (3.5 ± 2.1) points] in the test group were significantly lower than those in the control group. The good prognosis rate at 90 days postoperatively (54.9 vs. 35.2%, P = 0.018) was significantly higher in the test group than in the control group. The 90-day mortality rate was not statistically significant (7.0 vs. 8.5%, P=0.754). Immediately after surgery and 1 day after surgery, SOD, IL-10, and RBM3 levels in the test group were relatively higher than those in the control group, and the differences were statistically significant. Immediately after surgery and 1 day after surgery, MDA and IL-6 levels in the test group were relatively reduced compared with those in the control group, and the differences were statistically significant (P < 0.05). In the test group, RBM3 was positively correlated with SOD and IL-10. Conclusion: Mechanical thrombectomy combined with intraarterial cold saline perfusion is a safe and effectivemeasure for the treatment of acute cerebral infarction. Postoperative NIHSS scores and infarct volumes were significantly improved with this strategy compared with simple mechanical thrombectomy, and the 90-day good prognosis rate was improved. The mechanism by which this treatment exerts its cerebral protective effect may be by inhibiting the transformation of the ischaemic penumbra of the infarct core area, scavenging some oxygen free radicals, reducing inflammatory injury to cells after acute infarction and ischaemia-reperfusion, and promoting RBM3 production in cells. [ABSTRACT FROM AUTHOR] more...

As the oil field production time increases, oil seepage channel plugging will occur near the wellbore. The chemical deblocking method has high cost and short deblocking effective period, causing secondary damage to oil wells, and easily causing prominent problems such as environmental pollution. The permeability enhancement technology of pulse power controllable shock wave is a technology for oil layer treatment through the high-pressure discharge in downhole fluid. It uses the strong nonlinearity controllable shock wave generated by the hydroelectric effect explosion to cause directional propagation of pressure pulse in the formation, which generates strong shock and vibration force on various media in the formation and pores. Under the action of the shockwave, micro-fracture is generated on the reservoir, which can relieve the plugging and increase the injection. Compared with other physical and chemical unplugging technologies, the technology has the advantages of simple construction process, low operation cost and controllable energy. [ABSTRACT FROM AUTHOR] more...

Micro-porous activated carbons (ACs) with a narrow pore size distribution of 0.4-0.6nm and high specific surface areas (1160-1315 m2 · g-1 are prepared from environment-friendly, low-grade potassium humate (HA-K, carbon resource) and mild activating agent potassium acetate (CH3COOK). Microstructure characterizations indicate that the introduction of activating agent CH3COOK is a key step to achieve high specific surface area and carbonization degree. These ACs contain small amount of oxygen and nitrogen, and show obvious pseudo-capacitance besides double layer capacitance. As a result, the optimized ACs achieve high specific capacitances of 311F·g-1 and 317F·g-1 at 0.1A·g-1 in 2M KOH and 1M H2SO4 aqueous electrolytes, respectively. This sample also shows a good charge-discharge cycling stability within 10 000 cycles. [ABSTRACT FROM AUTHOR] more...

Based on sensory descriptors developed by a sensory evaluation panel for 48 commercial Chinese brewed soy sauce samples, a flavor wheel of Chinese brewed soy sauce with 55 descriptors in the dimensions of aroma and flavor was developed for the first time. Meanwhile, a lexicon of sensory descriptors for brewed soy sauce containing reference samples with different intensities was established, and 20 brewed soy sauce samples of different grades and from different geographical origins were subjected to sensory evaluation by quantitative descriptive analysis (QDA) using this lexicon. The results showed that the characteristic flavor attributes of soy sauce were soy paste-like, salty, umami, Chinese herbal, and cooked soybean-like aromas. Through analysis of variance (ANOVA), principal component analysis (PCA) and discriminant analysis (DA), it was found that there were significant differences in sensory properties among soy sauce of different grades and from different regions. This study can provide a methodological reference for sensory quality analysis of Chinese brewed soy sauce. more...