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Objective. This study focuses on the identification of risk factors, classification of stroke level, and evaluation of the importance and interactions of various patient characteristics using cohort data from the Second Hospital of Lanzhou University. Methodology. Risk factors are identified by evaluation of the relationships between factors and response, as well as by ranking the importance of characteristics. Then, after discarding negligible factors, some well-known multicategorical classification algorithms are used to predict the level of stroke. In addition, using the Shapley additive explanation method (SHAP), factors with positive and negative effects are identified, and some important interactions for classifying the level of stroke are proposed. A waterfall plot for a specific patient is presented and used to determine the risk degree of that patient. Results and Conclusion. The results show that (1) the most important risk factors for stroke are hypertension, history of transient ischemia, and history of stroke; age and gender have a negligible impact. (2) The XGBoost model shows the best performance in predicting stroke risk; it also gives a ranking of risk factors based on their impact. (3) A combination of SHAP and XGBoost can be used to identify positive and negative factors and their interactions in stroke prediction, thereby providing helpful guidance for diagnosis.

Microglia continuously survey the brain parenchyma and actively shift status following stimulation. These processes demand a unique bioenergetic programme; however, little is known about the metabolic determinants in microglia. By mining large datasets and generating transgenic tools, here we show that hexokinase 2 (HK2), the most active isozyme associated with mitochondrial membrane, is selectively expressed in microglia in the brain. Genetic ablation of HK2 reduced microglial glycolytic flux and energy production, suppressed microglial repopulation, and attenuated microglial surveillance and damage-triggered migration in male mice. HK2 elevation is prominent in immune-challenged or disease-associated microglia. In ischaemic stroke models, however, HK2 deletion promoted neuroinflammation and potentiated cerebral damages. The enhanced inflammatory responses after HK2 ablation in microglia are associated with aberrant mitochondrial function and reactive oxygen species accumulation. Our study demonstrates that HK2 gates both glycolytic flux and mitochondrial activity to shape microglial functions, changes of which contribute to metabolic abnormalities and maladaptive inflammation in brain diseases.

Allosteric regulation plays a fundamental role in innumerable biological processes. Understanding its dynamic mechanism and impact at the molecular level is of great importance in disease diagnosis and drug discovery. Glycogen phosphorylase (GP) is a phosphoprotein responding to allosteric regulation and has significant biological importance to glycogen metabolism. Although the atomic structures of GP have been previously solved, the conformational dynamics of GP related to allostery regulation remain largely elusive due to its macromolecular size (∼196 kDa). Here, we integrated native top-down mass spectrometry (nTD-MS), hydrogen-deuterium exchange MS (HDX-MS), protection factor (PF) analysis, molecular dynamics (MD) simulations, and allostery signaling analysis to examine the structural basis and dynamics for the allosteric regulation of GP by phosphorylation. nTD-MS reveals differences in structural stability as well as oligomeric state between the unphosphorylated (GPb) and phosphorylated (GPa) forms. HDX-MS, PF analysis, and MD simulations further pinpoint the structural differences between GPb and GPa involving the binding interfaces (the N-terminal and tower-tower helices), catalytic site, and PLP-binding region. More importantly, it also allowed us to complete the missing link of the long-range communication process from the N-terminal tail to the catalytic site caused by phosphorylation. This integrative MS and in silico-based platform is highly complementary to biophysical approaches and yields valuable insights into protein structures and dynamic regulation.

Two-dimensional (2D) MoS2 nanomaterials have been extensively studied due to their special structure and high theoretical capacity, but it is still a huge challenge to improve its cycle stability and achieve superior fast charge and discharge performance. Herein, a facile one-step hydrothermal method is proposed to synthetize an ordered and self-assembled MoS2 nanoflower (MoS2/C NF) with expanded interlayer spacing via embedding a carbon layer into the interlayer. The carbon layer in the MoS2 interlayer can speed the transfer of electrons, while the nanoflower structure promotes the ions transport and improves the structural stability during the charging/discharging process. Therefore, MoS2/C NF electrode exhibits exceptional rate performance (318.2 and 302.3 mAh·g−1 at 5.0 and 10.0 A·g−1, respectively) and extraordinary cycle durability (98.8% retention after 300 cycles at a current density of 1.0 A·g−1). This work provides a simple and feasible method for constructing high-performance anode composites for sodium ion batteries with excellent cycle durability and fast charge/discharge ability.

The objective of this work is to demonstrate the tempering response quantification approach for process - property optimization in the heat affected zone (HAZ) of SA-508 Gr. 2 Cl. 1 (formerly designated as SA-508 Cl. 2) subjected to temper bead welding (TBW). The tempering response in the CGHAZ and ICHAZ was quantified by a series of TBW thermal history simulations, followed by microstructural characterization and hardness measurements. Tempering response predictive equations were developed utilizing a version of the Grange Baughman parameter (GBP), modified to reflect the thermal histories in multi-pass welding. In parallel, the accuracy of the tempering response quantification and predictive hardness equations were validated. Validation was achieved through experimental welding with thermal history acquisition, determination of a predicted hardness value using the recorded thermal data, and comparison of the predicted values with micro-hardness measurements.

Cholesteric liquid crystals (CLCs) have been widely applied in optical filters due to Bragg reflection caused by their helical structure. However, the reflectivity of CLC filters is relatively low, commonly less than 50%, as the filters can only reflect light polarized circularly either left- or right-handedly. Therefore, a high-reflective CLC filter with a single-layer template was proposed which may reflect both right- and left-handed polarized light. The CLC filters of the red, green, blue color were fabricated by the templating technology, which show good wavelength consistency. Additionally, a multi-phase liquid crystal filter with high reflectance was demonstrated by the single-layer templating technology. The templated CLC or multi-phase liquid crystal filters show great potential applications in the optical community, reflective display, and lasing.

The main tasks of the space station are to execute the manned space flight activities, scientific experiments, observation of astronomical phenomena, and maintenance of satellites for a long time. For a lot of scientific applications, it is necessary to increase the pressure in the cabin, which leads to the difference between the internal and external pressure. Then, the strain can be generated. The real-time and accurate monitoring of the strain on the cabin is one of the important factors to ensure the safety of astronauts. In China, it is the first time to measure the strain of the cabin by means of fiber Bragg grating (FBG) sensors. The optical fiber sensor has a measurement error of less than 4.52 μe in the circumferential direction as compared with a resistance strain gauge acted as a reference. But the axial measurement error is very big, and the maximum is 28.93 μe. As a comparison, the strain of bare fiber in the axial direction is measured, and it is found that the error is terribly small. According to theoretical calculations, the transverse effect coefficient is 0.0271, and the experimental result is 0.0287. These two values are approximately consistent. By compensating the transverse effect of the FBG sensor, the measurement error is decreased by about one order of magnitude. It will be conducive to accomplish the health monitoring and condition assessment of space station.

We study the problem of deep recall model in industrial web search, which is, given a user query, retrieve hundreds of most relevant documents from billions of candidates. The common framework is to encoding queries and documents separately into distributed representations and match them in latent semantic space. However, all the exiting deep encoding models only leverage the information of the document itself, which is often not sufficient in practice when matching with query terms, especially for the hard tail queries. In this work we aim to leverage the additional information for documents from their co-click neighbours to help document retrieval. The challenges include how to effectively extract information and eliminate noise when involving co-click information while meet the demands of industrial scalability for real time online serving. To handle the noise in co-click relations, we firstly propose a web-scale Multi-Intention Co-click document Graph(MICG) which builds the co-click connections between documents on click intention level but not on document level. Then we present an encoding framework MIRA based on Bert and graph attention networks which leverages a two-factor attention mechanism to aggregate neighbours. To meet the online latency requirements, we only involve neighbour information in document side which can save the time-consuming query neighbor search in real time serving. We conduct extensive offline experiments on two public datasets and one private web-scale dataset from major commercial search engines(Bing1 and Sougou2) demonstrating the effectiveness and scalability of the proposed method compared with several baselines. And a further case study reveals that co-click relations mainly help improve web search quality from two aspects: key concept enhancing and query term complementary.

Recurrent inactivated mutations in central precocious puberty-associated gene MKRN3 lead to lung cancer proliferation and progression through PABPC1 ubiquitination–mediated global protein synthesis. MKRN3 is a bona fide tumor suppressor, and MKRN3-PABPC1 deregulation represents a key pathway in NSCLC oncogenesis., Central precocious puberty (CPP), largely caused by germline mutations in the MKRN3 gene, has been epidemiologically linked to cancers. MKRN3 is frequently mutated in non–small cell lung cancers (NSCLCs) with five cohorts. Genomic MKRN3 aberrations are significantly enriched in NSCLC samples harboring oncogenic KRAS mutations. Low MKRN3 expression levels correlate with poor patient survival. Reconstitution of MKRN3 in MKRN3-inactivated NSCLC cells directly abrogates in vitro and in vivo tumor growth and proliferation. MKRN3 knockout mice are susceptible to urethane-induced lung cancer, and lung cell–specific knockout of endogenous MKRN3 accelerates NSCLC tumorigenesis in vivo. A mass spectrometry–based proteomics screen identified PABPC1 as a major substrate for MKRN3. The tumor suppressor function of MKRN3 is dependent on its E3 ligase activity, and MKRN3 missense mutations identified in patients substantially compromise MKRN3-mediated PABPC1 ubiquitination. Furthermore, MKRN3 modulates cell proliferation through PABPC1 nonproteolytic ubiquitination and subsequently, PABPC1-mediated global protein synthesis. Our integrated approaches demonstrate that the CPP-associated gene MKRN3 is a tumor suppressor., Graphical Abstract

Class I histone deacetylases (HDACs) are promising targets for epigenetic therapies for a range of diseases such as cancers, inflammations, infections and neurological diseases. Although six HDAC inhibitors are now licensed for clinical treatments, they are all pan-inhibitors with little or no HDAC isoform selectivity, exhibiting undesirable side effects. A major issue with the currently available HDAC inhibitors is that they have limited specificity and target multiple deacetylases. Except for HDAC8, Class I HDACs (1, 2 and 3) are recruited to large multiprotein complexes to function. Therefore, there are rising needs to develop new, hopefully, therapeutically efficacious HDAC inhibitors with isoform or complex selectivity. Here, upon the introduction of the structures of Class I HDACs and their complexes, we provide an up-to-date overview of the structure-based discovery of Class I HDAC inhibitors, including pan-, isoform-selective and complex-specific inhibitors, aiming to provide an insight into the discovery of additional HDAC inhibitors with greater selectivity, specificity and therapeutic utility.

The objective of this work was to develop a procedure for evaluation and quantification of the tempering efficiency of corrosion resistant weld overlays used in the power generation and oil and gas industries. Three two-layer weld overlays of Alloy 625 on Grade 22 steel plates were produced using GTAW cold wire procedures. Typical welding parameters corresponding to low, medium, and high heat input were utilized. The overlays consisted of nine beads on the first layer and five to seven beads on the second layer. The weld thermal histories experienced in the coarse-grained heat affected zone (CGHAZ) were measured with Type K thermocouples and recorded with a 55 Hz sampling rate. Two rows of seven thermocouples were used in each overlay: one row located in a mid-bead position beneath the center bead of the overlay and the other row located in the nearest bead overlap position. Additionally, one Type C thermocouple was plunged into the weld pool of a second layer weld bead. The acquired thermal histories and the CGHAZ hardness at the thermocouple locations were evaluated to quantify the tempering efficiency in each welding procedure. The weld thermal histories with peak temperatures between 500°C, assumed as the minimum tempering temperature, and the base metal AC1 temperature were considered as tempering thermal cycles. The number of tempering thermal cycles and the sum of tempering cycle’s peak temperatures in each thermocouple location, as well as the corresponding hardness were used to quantify the tempering response efficiency for each of the three welding procedures. The results of this study will be used for validation of a computational model-based approach for prediction of tempering response and optimization of temper bead welding procedures.

Deep matching models aim to facilitate search engines retrieving more relevant documents by mapping queries and documents into semantic vectors in the first-stage retrieval. When leveraging BERT as the deep matching model, the attention score across two words are solely built upon local contextualized word embeddings. It lacks prior global knowledge to distinguish the importance of different words, which has been proved to play a critical role in information retrieval tasks. In addition to this, BERT only performs attention across sub-words tokens which weakens whole word attention representation. We propose a novel Global Weighted Self-Attention (GLOW) network for web document search. GLOW fuses global corpus statistics into the deep matching model. By adding prior weights into attention generation from global information, like BM25, GLOW successfully learns weighted attention scores jointly with query matrix $Q$ and key matrix $K$. We also present an efficient whole word weight sharing solution to bring prior whole word knowledge into sub-words level attention. It aids Transformer to learn whole word level attention. To make our models applicable to complicated web search scenarios, we introduce combined fields representation to accommodate documents with multiple fields even with variable number of instances. We demonstrate GLOW is more efficient to capture the topical and semantic representation both in queries and documents. Intrinsic evaluation and experiments conducted on public data sets reveal GLOW to be a general framework for document retrieve task. It significantly outperforms BERT and other competitive baselines by a large margin while retaining the same model complexity with BERT., 8pages,2figures

To realize the accurate measurement of strain parameters for spacecraft structure in the high and low temperature of aerospace environment, an optical fiber sensing approach is presented, which can satisfy the requirement of engineering application. © 2020 The Author(s)

The phase velocity matching Lamb waves are considered as an effective solution to excitation in the detection of nonlinear ultrasound early fatigue damage. In general, it is difficult to meet the phase velocity matching in real-world measurement. In this paper an approach to approximate phase velocity matching early fatigue damage detection is proposed. With the third harmonic approximate phase velocity matching modes treated as excitation frequencies by the Lamb wave dispersion curve, an analysis is conducted with regard to the time-frequency diagrams of the response signals at different frequencies. The change in the third harmonic amplitude with crack growth is analyzed by Fast Fourier Transform (FFT), which leads to the results suggesting that the third harmonic amplitude declines with crack growth. Moreover, a comparison is performed in the normalized relative third-order nonlinear parameters(NRTNP) of phase velocity matching and approximate phase velocity matching, with the relative deviation falling within 0.12.

At present, many flight tests of the new aircraft must be carried out by means of structural strength test. The method of resistance strain gauge is the effective method to measure strain in the flight test. However, the resistance strain gauge is used to measure strain, some questions occur. The workload of patch, welding line and sealing sheet is large and the efficiency is relatively low. When there are a large number of test points, the number of sensors and power supply wiring is relatively large, and the number of test channels is inevitably increased, resulting in the increase of the volume and weight of the test system. In addition, the resistance strain measurement method is greatly affected by environmental conditions, which affect the measurement accuracy and reliability. These problems are not well solved in the flight test. In the work, fiber Bragg grating sensors and resistance strain gauge are used to jointly monitor and compare the body strain in the loading process of unmanned aerial vehicle loading. The test shows that the fiber Bragg grating sensors can accurately monitor the strain of the unmanned aerial vehicle body with small errors, which demonstrate great potential in combat missions.

Heterostructures have gained intensive attentions in various energy storage fields due to their diverse physicochemical properties and functions, originating from the synergistic effects and interfacial interaction between the different components. However, it is still a great challenge to employ simple methods to design an advanced heterostructure for superior sodium storage performances. Herein, a facile in situ localized phase transformation strategy has been developed to transfer MoO3 nanoparticles anchored on rGO nanosheets into MoO2@MoS2 heterostructures (MoO2@MoS2/rGO). Benefiting from faster ion transport at the heterogeneous interface, higher conductivity as well as more active sites for Na storage than that of single component, MoO2@MoS2/rGO electrode exhibits distinguished reversible capacity (604.1 mAh g−1 at 0.1 A g−1) and remarkable rate performance (420.8 mAh g−1 at 5.0 A g−1) when evaluated as an anode for SIBs. This work provides a simple and feasible method for constructing stable heterostructures for high-performance energy storage materials.

Resistive switching (RS) effect has attracted enormous attention due to its potential for application of resistive random access memory with fast speed, good scalability and high endurance. NiO is a model system of RS effect, in which the formation/rupture of nickel filaments is directly related to the RS effect. In fact, it is still controversial that the RS effect in NiO films should be attributed to whether a single filament or multi-filaments. In this work, we demonstrate that multi-filaments are involved in the RS process by means of conventional I-V measurements, conductive atomic force microscopy and transmission electron microscopy. Furthermore, we observed the interesting tunneling magnetoresistance in this system for the first time, which not only reveals the mechanism of multi-filaments, but also provides a new way for multifunctional devices.

The resistive switching (RS) effect in various materials has attracted much attention due to its interesting physics and potential for applications. NiO is an important system and its RS effect has been generally explained by the formation/rupture of Ni-related conducting filaments. These filaments are unique since they are formed by an electroforming process, so it is interesting to explore their magnetoresistance (MR) behavior, which can also shed light on unsolved issues such as the nature of the filaments and their evolution in the RS process, and this behavior is also important for multifunctional devices. Here, we focus on MR behavior in NiO RS films with different resistance states. Rich and interesting MR behaviors have been observed, including the normal and anomalous anisotropic magnetoresistance and tunneling magnetoresistance, which provide new insights into the nature of the filaments and their evolution in the RS process. First-principles calculation reveals the essential role of oxygen migration into the filaments during the RESET process and can account for the experimental results. Our work provides a new avenue for exploration of the conducting filaments in resistive switching materials and is significant for understanding the mechanism of RS effect and multifunctional devices.

The determination of research direction is a complicated process, especially in the case of architectural research projects. General research projects, especially engineering projects, usually have several characteristics: first, large amount of capital. Second, the work cycle is long. Third, the return is unknown. Therefore, it is particularly important to establish an evaluation system for engineering research projects. This paper analyzes the literature on the civil engineering. The original index factors were extracted and the final index was determined by expert group discussion. Analytic hierarchical analysis (AHP), computer calculation (MATLAB) and hand calculation are used to determine the weight factor. In this paper, real cases are introduced to help leaders of Z enterprise to make decisions on scientific research projects. Based on this case, it can provide reference for other civil engineering research projects

In the process of flight for in-orbit spacecraft, debris and particles in space will collide with the spacecraft at a high speed. These collision will produce strain, pit or perforation on the surface of the spacecraft cabin, forming damage accumulation. Therefore, it is necessary to monitor the strain and impact position of the spacecraft cabin in real time, which will provide a basis for ensuring the reliability and safety of the spacecraft. In this paper, the achievement of strain and vibration information during the process of impact is designed in two ways: touched style and untouched style. The design of touched style needs to meet the requirements of large capacity/ultra-high speed monitoring. The design of untouched style needs to meet the acquisition of high frequency vibration signal in the impact process.

In the fields of civil engineering, aerospace and mechanical manufacturing, inertia mass is a very common form of load. The research on the response of inertia mass under dynamic load can provide a strong basis for the research in the above fields. In this paper, in order to study the response of inertia mass under dynamic load, a high-speed dynamic actuator is used to carry out sinusoidal loading and impact loading on an inertia mass, and its response under dynamic load is studied, which can provide a basic basis for the follow-up study of inertia mass. It can be concluded from the response analysis of inertia mass that the motion of inertia mass satisfies the basic laws of kinematics and dynamics.

With the progress of engineering, technology viscous damper are widely used in the field of engineering structures. Its principle is that when the external normal disturbance on the structure, the viscous damper will not generate damping force on the structure; when there is a strong external disturbance (strong earthquake, strong wind), The dampers can produce a reaction force, which can reduce the damage of the structure and improve its seismic capability. In this paper, the new viscous damper has been experimentally tested, including: 1. Test for maximum damping force; 2. Test for damping coefficient, damping exponent; 3. hysteresis curve. By analyzing the experimental data, the actual performance parameters of the new viscous damper are obtained, which provides certain support for future mass production and use of the product.

The Chinese space station is designed to carry out manned spaceflight, space science research, and so on. In serious applications, it is a common operation to inject gas into the hull, which can produce strain of the bulkhead. Accurate measurement of strain for the bulkhead is one of the key tasks in evaluating the health condition of the space station. This is the first work to perform strain detection for the Chinese space station bulkhead by using optical fiber Bragg grating. In the period of measurements, the resistance strain gauge is used as the strain standard. The measurement error of the fiber optical sensor in the circumferential direction is very small, being less than 4.52 &mu, &epsilon, However, the error in the axial direction is very large with the highest value of 28.93 &mu, Because the measurement error of bare fiber in the axial direction is very small, the transverse effect of the substrate of the fiber optical sensor likely plays a role. The comparison of the theoretical and experimental results of the transverse effect coefficients shows that they are fairly consistent, with values of 0.0271 and 0.0287, respectively. After the transverse effect is compensated, the strain deviation in the axial detection is smaller than 2.04 &mu, It is of great significance to carry out real-time health assessment for the bulkhead of the space station.