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AbstractSpatial reasoning of hierarchical relations is an important research topic in geographic information science. Existing literature focuses mainly on hierarchical relations according to ordered containment of point sets based on the 9-Intersection Model (9IM). However, in natural language descriptions, hierarchical relations expressed by prepositions such as in can have spatial configurations conflicting with those hierarchical relations based on 9IM. This paper proposes an algorithm employing combined hierarchies to infer hierarchical relations among places in different contexts. Two graph databases containing combined hierarchies conforming to administrative reach and geometric enclosure are established with places represented by polygons with misaligned boundaries on prototypical and real data. The 13170 pairs of conflicting hierarchical relations with the same start nodes but different end nodes detected in the combined hierarchies on real data validate the proposed algorithm for spatial reasoning of hierarchical relations in different contexts. This research facilitates consistent spatial reasoning of hierarchical relations in different contexts for spatial information retrieval and question answering. [ABSTRACT FROM AUTHOR]

The design of government subsidies is essential in supporting collaborative innovation and promoting sustainable development in R&D networks. This study explores the influence of different government subsidy strategies designed for R&D networks on inter-enterprise knowledge transfer. Drawing upon evolutionary game theory, it examines how impact is contingent upon enterprises' risk attitudes and reputation effects. The results indicate that when enterprises exhibit homogeneous risk attitudes, government subsidy policies encouraging risk-seeking behaviors can effectively enhance the knowledge-transferring level. When enterprises possess heterogeneous risk attitudes, a greater diversity of risk attitudes leads to a more conducive environment for knowledge transfer. Incorporating a rigorous reputation tolerance into the design of government subsidies in R&D networks can effectively elevate knowledge transfer. Therefore, policymakers can design tailored government subsidies and incentive mechanisms grounded in enterprises' risk attitudes and reputation effects. This study provides theoretical and policy implications for designing government subsidies and collaboration in R&D networks. [ABSTRACT FROM AUTHOR]

High performance carbon fiber based on coal tar pitch is a new type of functional material with unique properties, such as light weight, high strength, high modulus, high thermal conductivity, high electrical conductivity and low thermal expansion coefficient. It is a new type of functional material for both military and civilian use. In order to study the preparation of high performance carbon fiber based on coal tar pitch, this article obtained high performance carbon fiber based on coal tar pitch through raw material pretreatment, spinnable asphalt modulation, asphalt melt spinning, non-melting, carbonization, graphitization and other processes, and characterized the performance of spinnable mesocase asphalt and carbon fiber. The results show that high-performance spinnable mesophase pitch can be prepared by three steps raw material refining, hydrogenation modification and thermal polymerization. The mesophase content is 95%, the softening point is 280 °C, and the 3000 m filament can be spun under melt spinning conditions of 375 °C and 0.01 MPa. After graphitization, the coal pitch-based carbon fiber has excellent mechanical properties, small structural defects and a diameter of 12 μm. The tensile strength is 3089 MPa, the elastic modulus is 689 GPa, and the thermal conductivity is 902 w/(m·K). [ABSTRACT FROM AUTHOR]

Garlic is a common cooking ingredient and used in traditional medicine in Asian countries. There is a growing attention on garlic due to its preventive characteristics in cardiovascular diseases (CVDs). Many studies have reviewed the association between garlic intake and CVDs; however, no consistent conclusions have been drawn. New clinical trials have also been conducted and could contribute to more solid statements. In order to systematically review the reliability of previous studies regarding the implication of garlic in the management of CVDs, we performed in-depth meta-analysis using the most up-to-date randomized clinical trials (RCTs) data with more systematic controls. According to the 22 studies included, the effects of garlic intake on lowering total cholesterol (TC) and low-density lipoprotein (LDL) are more noticeable with lower dosage and longer duration, especially in patients with CVDs. In addition, subgroup analysis indicated that appropriate diet intervention could be an important control factor that should be taken into consideration in any future study designs. [ABSTRACT FROM AUTHOR]

Background: The main aim of this study was to explore the spatial-temporal patterns of cause-specific CVD admission in Beijing using retrospective SaTScan analysis. Methods: A spatial-temporal analysis was conducted at the district level based on the rates of total and cause-specific CVD admissions, including coronary heart disease (CHD), atrial fibrillation (AF), and heart failure (HF) from 2013 to 2017. We used joint point regression, Global Moran's I and Anselin's local Moran's I, together with Kulldorff's scan statistic. Results: Hospital admission trend decreased during the study period. Admission rates followed a spatially clustered pattern with differences occurring between cause-specific CVDs. Clusters were mainly identified in ecological preservation areas, with a more likely cluster found in Daxing, Fangshan, Xicheng district for total CVD, CHD, AF and HF, respectively. Conclusions: Hospital admission of cause-specific CVD showed spatial clustered pattern, especially in ecological preservation areas. [ABSTRACT FROM AUTHOR]

With the substantial increase in vehicle population, the road safety problems such as accidents have become serious. In this paper, we propose a road-safety data delivery solution in vehicular sensor networks to solve road safety problems and improve driving safety. The road-safety data delivery in vehicular sensor networks is delay-sensitive, so this solution aims to reduce the road-safety data delivery latency by shortening the addressing, routing and handover delays. In the proposal, a new address structure is proposed to achieve the road-safety data delivery. Based on the new address structure, the address configuration can be achieved without duplicate address detection and the routing can be performed without route discovery. Moreover, multiple sensor devices can achieve handovers via one handover operation without performing time-consuming care-of address configuration. Finally, the proposal is analyzed and evaluated, and the data shows that the proposal effectively reduces the road-safety data delivery latency. [ABSTRACT FROM AUTHOR]

Policy scientists have long examined how policy innovation has emerged and diffused by focusing on the interaction between agents and policy programs. In contrast, this article focuses on how uncertainty in policy environments has affected the fate of policy innovation in an authoritarian state. Using original data from China's official newspaper, the People's Daily,it is found that the central government's decision to promote sensitive policy experiments is a function of the perceived risks in the policy environment. The U-shaped relationship between the promotion of sensitive policy innovation and inflation reflects the wire-walking behavior of China's central government. The central authority in China tends to promote fewer sensitive political experiments when inflation increases and resumes promoting experiments when the inflation rate passes a certain tipping point. It is also found that the central authority intentionally regulates the promotion of political experiments during important political events. [ABSTRACT FROM AUTHOR]

Obtaining both high hardness and toughness is a challenge in B4C-nano-adhesive composites. Solving the inhomogeneous distribution of nano-adhesives in B4C and forming the chemical bonding at grain boundary is an effective method. Here, we reported that the uniform distribution of titanium diboride (TiB2)-reinforced B4C composites synthesized by high-pressure and high temperature (HPHT). It is found that HPHT sintering can effectively inhibit the grain growth and increase the relative density. Moreover, HPHT sintering can cross high reaction energy barrier and effectively promote the formation of chemical bonding at grain boundary between B4C and TiB2. The optimal hardness and toughness value reach 30.0 ± 0.9 GPa and 7.87 MPa·m1/2, respectively. The improvement of hardness and toughness in the final products are ascribed to the strengthening of nanoTiB2 connection of B4C boundary and intergranular fracture mechanism. This work suggests a new way to achieve the uniform distribution of nanoTiB2 in B4C and form the chemical bonding at grain boundary, which is of great significance to the further development of TiB2-reinforced B4C composites with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

A novel method has been reported for 2,6-dichlorophenol using surface-enhanced Raman scattering (SERS). SiO2/gold composites were selected as the SERS substrates to provide the response of gold nanoparticles. Molecular imprinting was subsequently used for the development of a specific detector to 2,6-dichlorophenol with precipitation polymerization. The molecularly imprinted polymer provided sensitive and selective SERS detection for the determination of 2,6-dichlorophenol. The intensity and concentration obeyed a linear relationship from 1 × 10−5 to 1 × 10−9 mol L−1 2,6-dichlorophenol. The sensitivity of SERS with the molecularly imprinted polymers provides a promising approach for practical analysis. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptor (CAR) T-cell adoptive therapy is set to transform the treatment of a rapidly expanding range of malignancies. Although the activation process of normal T cells is well characterized, comparatively little is known about the activation of cells via the CAR. Here we have used flow cytometry together with single-cell transcriptome profiling to characterize the starting material (peripheral blood mononuclear cells) and CAR therapeutic products of 3 healthy donors in the presence and absence of antigen-specific stimulation. Analysis of 53,191 single-cell transcriptomes showed APRIL-based CAR products to contain several subpopulations of cells, with cellular composition reproducible from donor to donor, and all major cellular subsets compatible with CAR expression. Only 50% of CAR-expressing cells displayed transcriptional changes upon CAR-specific antigen exposure. The resulting molecular signature for CAR T-cell activation provides a rich resource for future dissection of underlying mechanisms. Targeted data interrogation also revealed that a small proportion of antigen-responding CAR-expressing cells displayed an exhaustion signature, with both known markers and genes not previously associated with T-cell exhaustion. Comprehensive single-cell transcriptomic analysis thus represents a powerful way to guide the assessment and optimization of clinical-grade CAR-T-cells, and inform future research into the underlying molecular processes. [ABSTRACT FROM AUTHOR]

The exponential growth of natural language text data in social media has contributed a rich data source for geographic information. However, incorporating such data source for GIS analysis faces tremendous challenges as existing GIS data tend to be geometry based while natural language text data tend to rely on natural language spatial relation (NLSR) terms. To alleviate this problem, one critical step is to translate geometric configurations into NLSR terms, but existing methods to date (e.g. mean value or decision tree algorithm) are insufficient to obtain a precise translation. This study addresses this issue by adopting the random forest (RF) algorithm to automatically learn a robust mapping model from a large number of samples and to evaluate the importance of each variable for each NLSR term. Because the semantic similarity of the collected terms reduces the classification accuracy, different grouping schemes of NLSR terms are used, with their influences on classification results being evaluated. The experiment results demonstrate that the learned model can accurately transform geometric configurations into NLSR terms, and that recognizing different groups of terms require different sets of variables. More importantly, the results of variable importance evaluation indicate that the importance of topology types determined by the 9-intersection model is weaker than metric variables in defining NLSR terms, which contrasts to the assertion of ‘topology matters, metric refines’ in existing studies. [ABSTRACT FROM PUBLISHER]

Partially linear additive model is useful in statistical modelling as a multivariate nonparametric fitting technique. This paper considers statistical inference for the semiparametric model in the presence of multicollinearity. Based on the profile least-squares (PL) approach and Liu estimation method, we propose a PL Liu estimator for the parametric component. When some additional linear restrictions on the parametric component are available, the corresponding restricted Liu estimator for the parametric component is constructed. The properties of the proposed estimators are derived. Some simulations are conducted to assess the performance of the proposed procedures and the results are satisfactory. Finally, a real data example is analysed. [ABSTRACT FROM PUBLISHER]

This paper proposes a mobility handover based on road domain (MHRD) for IPv6-based Vehicular Ad hoc NETworks. In MHRD, the architecture based on road domain is proposed in order to reduce the mobility handover frequency. Based on this architecture, the mobility handover algorithm is proposed. During the mobility handover process, a vehicle can receive the packets destined for the old care-of address (CoA) and new CoA, so the communication continuity is achieved and the packet loss rate is reduced. Moreover, a vehicle acquires a CoA from the neighbour access point without duplicate address detection, so the mobility handover cost and delay are reduced. This paper evaluates the performance parameters of MHRD, including the mobility handover cost and delay, and the data results show that MHRD reduces the mobility handover cost and delay. [ABSTRACT FROM PUBLISHER]

Graphs are widely used to present scientific information. Information presented in graphs can be classified into three kinds: explicit information, tacit information, and conclusive information. Reading information from graphs requires not only science content knowledge and understanding but also general logical reasoning. This study examined the abilities of reading various kinds of scientific information among students in different grades in China. The participants were 288 students in grades 9, 10, and 11. An instrument developed by the researchers and teachers was used to measure students' graph reading abilities. Results indicated that: (a) students' abilities of reading the three kinds of scientific information improved with grade; (b) students in different grades showed significant differences in reading all kinds of information except for the topics and special segments of the graphs for explicit information, tacit information requiring using mathematics tools, and conclusive information from comparison; and (c) as a whole, students of the same grade showed variation in their abilities of reading different kinds of information but the patterns of difference among the three kinds of information for the three grades were similar. This study has many implications for science education in China. It may help teachers understand students' thinking approaches to graphs and foster their abilities of interpreting them, and further inform future studies on how to adopt and design graphs in science textbooks. [ABSTRACT FROM PUBLISHER]

Background: Sciatica is a phrase used to describe radiating leg discomfort. The most common cause is lumbar disc herniation (LDH), which is considered to start in the nucleus pulposus. Advancements in lipidomics and metabolomics have unveiled the complex role of fatty acid metabolism (FAM) in both healthy and pathological states. However, the specific roles of fatty acid metabolism-related genes (FAMGs) in shaping therapeutic approaches, especially in LDH, remain largely unexplored and are a subject of ongoing research. Methods: The junction of the weighted correlation network analysis (WGCNA) test with 6 FAMGs enabled the finding of FAMGs. Gene set variation analysis (GSVA) was used to identify the possible biological activities and pathways of FAMGs. LASSO was used to determine diagnostic effectiveness of the four FAMGs in diagnosing LDH. GSE124272, GSE147383, GSE150408, and GSE153761 were utilized to confirm the levels of expression of four FAMGs. Results: Four FAMGs were discovered [Acyl-CoA Thioesterase 4 (ACOT4), Cytochrome P450 Family 4 Subfamily A Member 11 (CYP4A11), Acyl-CoA Dehydrogenase Long Chain (ACADL), Enoyl-CoA Hydratase and 3-Hydroxyacyl CoA Dehydrogenase (EHHADH)] For biological function analysis, mhc class ib receptor activity, response to thyroxine, response to l phenylalanine derivative were emphasized. Conclusions: FAMGs can help with prognosis and immunology, and provide evidence for fatty acid metabolism-related targeted therapeutics. In LDH, FAMGs and their interactions with immune cells might be therapeutic targets. [ABSTRACT FROM AUTHOR]