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This study investigates the effects of orientation and strain rate on the hydrogen-enhanced localized plasticity mechanism during shear deformation of interstitial free steel. The stress-orientation correlation of hydrogen embrittlement is related to atomic-scale mechanisms, as evidenced through in situ electron backscatter diffraction, slow-strain-rate shear testing, electron microscopic characterization, and molecular dynamics simulations. The dislocation density increment after hydrogen charging was 59.25% higher along the [100] crystallographic zone axis than along the [11‾1‾] crystallographic zone axis, which is mainly attributed to the combined effect of strain-induced transport and interstitial diffusion of hydrogen atoms. The strain rate correlation of hydrogen embrittlement is also affected by the interstitial diffusion during the strain-induced transport of H. Interstitial diffused hydrogen induce dislocation forest emissions that promote local plasticity, which ultimately leads to the orientation and strain rate correlation of hydrogen embrittlement.

Understanding the mechanism of oxygen on toughness of titanium alloys is crucial for popularizing powder metallurgy. In this work, the effect of oxygen content (1500, 3000 and 5000 ppm) on the impact toughness of powder metallurgically modified titanium alloys with fine equiaxed microstructures (∼1.5 μm) was systematically investigated. With increasing oxygen content, the c/a value of the α-phase lattice parameter increases to a maximum of 1.593 Å, and the hardness increases from 4.03 GPa to 5.05 GPa, resulting in an increase in strength of ∼150 MPa and a considerable decrease in the ability of the two phases to coordinate. The crack initiation energy is similar for different oxygen contents, whereas the crack propagation energy increases considerably with decreasing oxygen content; the impact energy of stable crack extension increases from 4 J to 13 J and 35 J, and the impact energy of unstable crack extension and crack collapse stages increases from zero to 14 J and 25 J, respectively, indicating that decreasing oxygen content can substantially improve the crack extension resistance. The activation of numerous dislocations within the two phases and the formation of subgranular boundaries at low oxygen contents promote the release of internal stresses in the grains, and simultaneously, the interfacial resistance to dislocation migration and the concentration of interfacial stresses are also reduced, which improves the coordination of the two-phase plastic deformation of the equiaxed microstructures; the crack extension paths in the impact process become more tortuous and finally achieve impact energies as high as 85–100 J.

Vacuum induction melting has proven to be a cost-efficient way to fabricate TiNi alloys with excellent compositional homogeneity and uniformity. However, the high reactivities of TiNi alloys generate aggressive melt attacks with a particular ceramic crucible. Here, the performance of AlN crucible for melting TiNi alloys was investigated, and the underlying mechanisms for the interfacial interactions were revealed. The results demonstrated the feasibility of using AlN crucibles for induction melting of TiNi alloys. Specifically, melt infiltration was suppressed and thus physical erosion was diminished by reducing the apparent porosity of the crucible. Further investigations combined with a theoretical analysis revealed that the TiN barrier layer distributed on the crucible surface was formed in situ due to crucible/melt interactions, which protected the ceramic matrix from further melt attack and limited the contaminant levels. Our work provides a viable pathway for the preparation of high-quality TiNi alloys via induction melting.

Achieving high green density is essential for ensuring the mechanical properties of powder metallurgy workpieces. However, the densification behavior of irregular ductile powders remains unclear due to oversimplification in current numerical simulations. To address this, a three-dimensional multi-particle finite element method model incorporating realistic powder morphology, size distribution, and stacking structure is constructed. It is found that a pivotal motion-deformation synergistic stage exists between the conventional particle rearrangement and elastic–plastic deformation stages. In this stage, plastic deformation is driven by the spheroidization of coarse powders, whereas the resulting vacancies in the stacking structure facilitate slight particle motion. Thereafter, plastic deformation is dominated by the flattening of fine particles, and the pore-filling capacity decreases due to the reduction in non-contact surface area. This synergistic and complementary interaction between the spheroidization of coarse powders and the flattening of fine powders enhances mechanical interlocking and promotes micropore closure. As a result, the micropores exhibit a tendency of downsizing and homogenization, substantially boosting the potential for achieving full densification during sintering. Based on these findings, a method for determining the optimal forming pressure is proposed, considering the manufacturing costs of powder compacts and the characteristics of the micropores in both green and sintered bodies.

Abstract Research objective Triadic patent (TP) families and Patent Cooperation Treaty (PCT) applications are often used as datasets to measure innovation capability or R&D internationalization, but their concordance is unclear, which is the main issue in this study. Methods We collect the global TP and PCT data from the Derwent Innovations Index (DII), and a total of 1,589,172 TP families and 4,067,389 PCT applications are retrieved. Based on International Patent Classification (IPC) codes, we compare these two big datasets in three parts: IPC distribution, IPC co-occurrence network, and nation-IPC co-occurrence network. In order to understand the overall similarities and differences between TP and PCT, we make the basic statistics of the global data and w-core defined based on the w-index. Furthermore, the w-cores are visualized and the global similarities are calculated for the detailed concordance and differences. Findings The result shows that the w-core is suitable to select the core part of big data and TP and PCT get high concordance. Meanwhile, in technological convergence, some specific technical fields (e.g. chemistry, medicine, electronic communication, and lighting technology) and countries/regions (e.g. Germany, Japan, China, and Korea), there are a few differences. Practical implications TP families are very similar to PCT applications in terms of reflecting innovation capability or R&D internationalization at a macro level, but when it comes to technological convergence, specific research topics, and countries/regions, the choice may depend on the purpose of the research.

Neural stem progenitor cell (NSPC) transplantation has been regarded as a promising therapeutic method for spinal cord injury (SCI) repair. However, different NSPCs may have different therapeutic effects, and it is therefore important to identify the optimal NSPC type. In our study, we compared the transcriptomes of human fetal brain-derived NSPCs (BNSPCs), spinal cord-derived NSPCs (SCNSPCs) and H9 embryonic stem-cell derived NSPCs (H9–NSPCs) in vitro and subsequently we transplanted each NSPC type on a collagen scaffold into a T8-9 complete SCI rat model in vivo. In vitro data showed that SCNSPCs had more highly expressed genes involved in nerve-related functions than the other two cell types. In vivo, compared with BNSPCs and H9–NSPCs, SCNSPCs exhibited the best therapeutic effects; in fact, SCNSPCs facilitated electrophysiological and hindlimb functional recovery. This study demonstrates that SCNSPCs may be an appropriate candidate cell type for SCI repair, which is of great clinical significance.

ObjectiveUsing Mesh Meta Analysis to evaluate the efficacy of Acupuncture & Moxibustion, Clomiphene, Acupuncture & Moxibustion combined with Clomiphene for treating Polycystic Ovary Syndrome (PCOS), in order to provide evidence-based medical evidence for whether to recommend Acupuncture & Moxibustion or Combine western medicine to treat PCOS.MethodsEight databases including The Cochrane Library, Pubmed, Embase, Web of Science, CNKI, Wanfang Date, VIP and CBM were searched by computer. The included research period is from the establishment of the database to May 2023, which concerned with randomized controlled trials involving Acupuncture & Moxibustion, Clomiphene, Acupuncture & Moxibustion combined with Clomiphene on ovulation induction and pregnancy outcome in patients with PCOS. The duration of the research paper is from 2016 to 2023.The inclusion criteria refer to the Rotterdam standards issued by the European Center for Human Reproduction and Embryology and the American Society of Reproductive Medicine in January 2003, or the Expert Consensus on the Diagnosis and Treatment of Polycystic Ovarian Syndrome by the Endocrinology Group of the Obstetrics and Gynecology Branch of the Chinese Medical Association. Simultaneously exclude related diseases, repetitive literature, as well as literature with incomplete abstract information and no original data provided. Two researchers independently screened the literature, extracted data, and evaluated the risk of bias included in the study, using Stata17.0 software for a mesh meta-analysis.ResultsSix randomized controlled trials were included, covering 1410 PCOS patients. Three interventions included Acupuncture & Moxibustion, Clomiphene, Acupuncture & Moxibustion combined with Clomiphene. Mesh Meta Analysis showed that in terms of improving ovulation rate, there was no statistical difference between Acupuncture & Moxibustion (A), Clomiphene (B), Clomiphene combined with Acupuncture & Moxibustion (C) (P>0.05).Acupuncture & Moxibustion (A) versus Clomiphene (B) [MD=0.15,95% CI (-0.51,0.80)], Acupuncture & Moxibustion (A) versus Clomiphene combined with Acupuncture & Moxibustion (C) [MD=1.60,95% CI (0.97,2.23)], Clomiphene (B) versus Clomiphene combined with Acupuncture & Moxibustion (C) [MD=1.45,95% CI (0.91,1.99)]. In terms of pregnancy outcome, the difference between the three intervention methods was statistically significant (P

Mechanical properties and thermal deformation capabilities of powder metallurgy (P/M) Ti alloys are extremely susceptible to pores in the sintered parts. However, deciphering the pores evolution mechanisms is exceedingly challenging and heretofore this problem has yet been unequivocally understood. To address it, 3D X-ray computed tomography (XCT) is herein employed to perform this investigation. It is found that three types of pores encompassing branch-like pores (type Ⅰ), flat pores (type Ⅱ), and snatchy spherical pores (type III) form in the green compacts after the cold isostatic pressing, which is fundamentally governed by the irregularity of powder profiles. During sintering, type I pores are first to be decomposed at the junctions where pores branch triggered by stress concentration and subsequently undergo splitting and spheroidizing, till converting to (near) spherical pores. Type II and III pores are basically showing analogical behavior excluding the branch break-up step. Moreover, pores orientation distribution is turned out to be temperature independent, nevertheless, pores connectivity and localized porosity are closely related to the sintering temperature. Besides, a spot of pores is inspected inside partial large-sized master alloy powder particles, i.e., at 1200 °C, which possibly originates from the Kirkendall’s effect between the alloying elements and the Ti matrix.

With the goal of harnessing the host’s immune system to provide long-lasting remission and cures for various cancers, the advent of immunotherapy revolutionized the cancer therapy field. Among the current immunotherapeutic strategies, immune checkpoint blockades have greatly improved the overall survival rates in certain patient populations. Of note, CTLA4 and PD-1/PD-L1 are two major non-redundant immune checkpoints implicated in promoting cancer immune evasion, and ultimately lead to relapse. Antibodies or inhibitors targeting these two c+heckpoints have achieved some encouraging clinical outcomes. Further, beyond the canonical immune checkpoints, more inhibitory checkpoints have been identified. Herein, we will summarize recent progress in immune checkpoint blockade therapies, with a specific focus on key pre-clinical and clinical results of new immune checkpoint therapies for cancer. Given the crucial roles of immune checkpoint blockade in oncotherapy, drugs targeting checkpoint molecules expressed by both cancer and immune cells are in clinical trials, which will be comprehensively summarized in this review. Taken together, investigating combinatorial therapies targeting immune checkpoints expressed by cancer cells and immune cells will greatly improve immunotherapies that enhance host elimination of tumors.

Real-time and high-precision water level monitoring is crucial for the fields of hydrology, hydraulic engineering, and disaster prevention and control. The most prevalent method for measuring water level is through the use of water level gauges, which can be costly and have limited coverage. In recent years, Global Navigation Satellite System Reflectometry (GNSS-R) technology has emerged as a promising approach for water level monitoring due to its low cost and high coverage. However, a limitation of current GNSS-R technology is the extended time required to record signals, which hinders its potential for real-time application. This paper introduces a novel real-time water level monitoring method based on GNSS dual-antenna attitude measurement and develops a model to invert water level based on baseline vector. This method uses double-difference observations to eliminate errors caused by various factors, such as satellite and receiver clock, and ionospheric and tropospheric delay. To avoid the impact of detecting and correcting cycle slips during real-time operations, a single-epoch calculation method is introduced. In order to verify the stability and reliability of our method, field tests were carried out at Dongshahe Station in Beijing. We obtained water level data with a time resolution of 1 Hz through field experiments. Experimental data collected from 12 May to 8 June 2022 and from 4 July to 8 August 2022 showed good agreement with on-site water gauge measurements, with root mean square errors of 2.77 cm and 2.54 cm, respectively. Experimental results demonstrate that this method can achieve high-precision, high-temporal-resolution water level monitoring.

The shipping industry has accelerated the transformation of its carbon emission reduction and decarbonization, and relevant patents are rapidly increasing, but the industry still lacks consensus on the low-carbon development route of ship propulsion technology. We used the Derwent Innovation Index to collect the global patent information on ship power systems between 1965 and 2022 and proposed a new patent information mining framework. It is used for the dynamic tracking and analysis of global technology correlation characteristics, hot technology topics, and competitive situations. The findings indicate that: (1) the innovation of ship power systems is more radical and concentrated in the fuel field represented by LNG technology, whereas technical innovation in the field of pure electric propulsion is more scattered. Small tonnage ships, underwater operations, and recreation technology are among its innovation hotspots. (2) Pure electric propulsion technology is dominated by combined innovation with other propulsion methods (hybrid propulsion technology) and Chinese universities have recently begun to lead this technology. (3) Fuel cells and remote control have become innovation hotspots. Fuel cell technology, which combines electric, fuel, and hybrid power technology, is now on the cutting edge of innovation and has the potential for disruptive innovation.

Pulmonary fibrosis is a fatal chronic progressive respiratory disease, characterized by continuous scarring of the lung parenchyma, leading to respiratory failure and death. The incidence of PF has increased over time. There are drugs, yet, there are some limitations. Hence, it is of importance to find new therapies and new drugs to replace the treatment of pulmonary fibrosis. In recent years, there have been a great number of research reports on the treatment of traditional Chinese medicine polysaccharides in various system fields. Among them, the treatment of PF has also gained extensive attention. This review summarized the source of polysaccharides, the drug activity of traditional Chinese medicine, and the protective effects on targets of Pulmonary fibrosis. We hope it can inspire researchers to design and develop polysaccharides, serving as a reference for potential clinical therapeutic drugs.

Self-driving vehicle (SDV) has become a new driving force in the automotive industry, but no scholars have yet to dig deep into the competitive technology intelligence in the SDV field. Therefore, this study analyzes technology, competition and cooperation from the perspective of global patents, aiming to provide a reference to governments, enterprises and research institutions to grasp the competition situation and timely find the new investment opportunities. In this study, the Derwent Innovation Index (DII) is selected as the data source, the Jaccard index instead of the International Patent Classification (IPC) co-occurrence frequency is used to reflect the technical correlation, Relative Technology Advantage (RTA) index and the International Business Potential (IBP) are used to represent the competition among enterprises, and multiple network indicators, including macro and micro, are used to measure cooperation. The results show that: 1. Vehicle control system is the most critical technology in SDV field; 2. Different types of companies show different competitive advantages. Auto manufacturing companies rely on their strong comprehensive strength to maintain their position, but component suppliers are most likely to become a powerful group to shake the existing industry order. 3. As far as global cooperation is concerned, the partnership led by core leaders is taking shape, but it is still in the early stage.

The main purpose of this study is to determine the spillover effect of real estate regulatory policies released by core cities on the surrounding cities in major urban agglomerations based on regional linkage characteristics of China's real estate market. In this study, real estate transaction data of 157 cities were selected from 11 major urban agglomerations. Agglomeration's housing transaction volatility and spillover effect caused by the core city's regulatory policies were simulated by integrating spatial and temporal analysis model, event analysis, and symbolic time series analysis. The findings showed that (1) the regional linkage of the real estate market in the Harbin–Changchun and Middle–South Liaoning, Middle Reaches of the Yangtze River, Yangtze River Delta, Pearl River Delta, and West Side of the Straits agglomerations were remarkably tight and the core cities' policy spillover effect was significant, of which the house purchase limitation and credit limitation policies had the widest influence; (2) the regional linkage of the real estate market in the Beijing–Tianjin–Hebei agglomeration, Shandong Peninsula, Guanzhong Plain, and Chengdu–Chongqing agglomerations was relatively weaker, but the core cities' policies of market regulation and taxation had certain spillover effect; (3) there were significant differences in the spillover effects of different types of policies in different urban agglomerations; (4) generally, the core cities' policy spillover often reduced the changing characteristics of the real estate market and made it more ordered with more certainty in the whole agglomeration, with the exception of the Beijing–Tianjin–Hebei, West Side of the Straits, and Chengdu–Chongqing agglomerations. Keywords: Policy spillover effect, Real estate policy, Urban agglomeration, Regional linkage, Spatiotemporal model, JEL classification: R12, R38

Answering a question of Wright, we show that spheres of any radius are always connected in the curve graph of surfaces Σ2,0, Σ1,3, and Σ0,6, and the union of two consecutive spheres is always connected for Σ0,5 and Σ1,2. We also classify the connected components of spheres of radius 2 in the curve graph of Σ0,5 and Σ1,2. [ABSTRACT FROM AUTHOR]

To accurately characterize the geometric structure of closed‐cell aluminum foam, a three‐dimensional stochastic sphere model with adjustable porosity and pore size was established, and its thermal conductivity was studied by numerical simulation. A closed‐cell aluminum foam heat conduction experiment was designed to verify the accuracy of the model. Using this model, the thermal conductivity of aluminum foam with different pore sizes and porosity was calculated, and the variation of thermal conductivity was studied. The results show that with the same porosity, the thermal conductivity increases linearly with the pore size. With the same pore size, the thermal conductivity decreases linearly with the porosity. The equivalent thermal conductivity decreases with the increase of porosity. According to the simulation results, the formula of equivalent thermal conductivity of aluminum foam is λd = −0.1548θ + 14.2236. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that regulatory T cells (Tregs) are pivotal in the regulation of T cell-mediated immune responses in atherosclerosis, a chronic autoimmune-like disease. In the authors' previous studies, it was demonstrated that amygdalin ameliorated atherosclerosis by the regulation of Tregs in apolipoprotein E-deficient (ApoE-/-) mice. Therefore, the aim of the present study was to investigate the therapeutic effect of amygdalin on low-density lipoprotein (LDL) receptor deficient (LDLR-/-) mice, and to examine its immune regulatory function by the stimulation of Tregs. To establish an atherosclerosis mouse model, the LDLR-/- mice were fed a high fat and high cholesterol diet then the total plasma cholesterol, triglyceride, LDL and chemokines levels were measured by an ELISA. Following sacrificing the mice, the upper sections of the aorta were stained by hematoxylin and eosin, and Oil red O to assess the plaque area. Then western blotting and reverse transcription polymerase chain reactions were performed to analysis the expression levels of cluster of differentiation 68, monocyte chemoattractant protein-1, matrix metalloproteinase (MMP)-2, MMP-9 and forkhead box P3 (Foxp3). To further confirm the activation of FOXP3 by amygdalin, lentiviruses carrying Foxp3 shRNA were injected into the mice, and the serum cytokines levels were measured by ELISA. Following feeding of the mice with a high-fat/high-cholesterol diet, the LDLR-/- mice demonstrated comparatively higher levels of triglyceride, total cholesterol and LDL, compared with levels in the amygdalin-treated mice. By comparing the vessel area, lumen area, plaque area, and percentage aortic plaque coverage, the effects of amygdalin on pre-existing lesions were assessed. In addition, the levels of CD68, monocyte chemoattractant protein-1, MMP-2 and MMP-9 were analyzed, and analysis of the expression of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α indicated that the mice treated with amygdalin had decreased expression of pro-inflammatory cytokines. The mRNA and protein levels of Foxp3 were also quantified, and the mice treated with amygdalin demonstrated an increased number of Tregs. The knockdown of Foxp3mRNA resulted in the increased secretion of IL-1β, IL-6 and TNF-α. Therefore, the data indicated that amygdalin regulated the formation of atherosclerosis and stabilized the plaque by suppressing inflammatory responses and promoting the immune-modulation function of Tregs. Taken together, the results demonstrated the therapeutic effect of amygdalin on atherosclerosis. [ABSTRACT FROM AUTHOR]

Serotonin-transporter-linked promoter region (5-HTTLPR) polymorphism is the genetic variant coding for the serotonin transporter and may play an important role in the etiology of depression. However, genetic studies examining the relationship between 5-HTTLPR polymorphism and geriatric depression have produced inconsistent results. We conducted a meta-analysis to compare the frequency of 5-HTTLPR variants in geriatric depression cases and non-depressed controls in the elderly. A total of 5 studies involving 579 geriatric cases and 1372 non-depressed controls met the inclusion criteria. With strong statistical power, pooled odds ratios (ORs) and 95% confidence intervals (CIs) for genotypic analyses (S carrier versus L/L, S/S versus L/L) were provided. The results of our analysis indicate statistically significant association between S allele and the risk of geriatric depression (OR S carrier vs S/S = 1.29, 95% CI 1.01-1.66; OR S/S vs L/L = 1.68, 95% CI 1.20-2.35). Our findings suggest that 5-HTTLPR polymorphism is of importance in the development of geriatric depression. [ABSTRACT FROM AUTHOR]