Search

The traditional modification design has some disadvantages such as complex calculation，uncontrollable tooth profile curve shape and unstable meshing performance，the pressure angle of the gear tooth profile has a great influence on the meshing force transmission performance. Therefore，a new tooth profile modification design method is proposed based on the distribution law of the pressure angle of the cycloid tooth profile. Based on the pressure angle distribution trend obtained by calculation and analysis，the mathematical model of tooth profile modification with straight-line method is established，and the function representation between the tooth profile pressure angle and the modification amount is deduced，the tooth contact analysis model is constructed，and the transmission error of modified cycloid-pin gear is obtained. Through the comparative measurement experiment of the tooth profile shape and transmission error of the cycloid，the correctness and effectiveness of the method proposed in the article are verified. This method considers the mutual influence between the pressure angle of the cycloidal gear tooth profile and the modification amount，and the technical problems of traditional modification method in calculation，processing，and active design are solved，and the trend of modification amount can be flexibly controlled，while ensuring the meshing performance，it obtains the design tooth profile that is closer to the theoretical cycloid.

Abstract Objective The number of older people is estimated to increase from 524 million in 2010 to 1.5 billion in 2050. The factors and models of human longevity and successful aging are questions that have intrigued individuals for thousands of years. For the first time, the current study was designed to investigate the relationships between sex hormones, bone turnover, abdominal obesity, nutritional status and centenarian longevity in the oldest females. Methods The China Hainan Centenarian Cohort Study was performed in 18 cities and counties of Hainan Province using standard methodology in 500 centenarian females and 237 oldest females aged between 80 and 99 years. Results Centenarians were inversely associated with the geriatric nutritional risk index [Exp(B) (95% CI): 0.901 (0.883–0.919)] and abdominal obesity [Exp(B) (95% CI): 0.719 (0.520–0.996)] and positively associated with prolactin [Exp(B) (95% CI): 1.073 (1.044–1.103)], progesterone [Exp(B) (95% CI): 44.182 (22.036–88.584)], estradiol [Exp(B) (95% CI): 1.094 (1.071–1.119)], osteocalcin [Exp(B) (95% CI): 1.041 (1.028–1.054)], β-crossLaps [Exp(B) (95% CI): 63.141 (24.482–162.848)] and parathyroid [Exp(B) (95% CI): 1.022 (1.013–1.031)] hormone levels (P

Cycloidal gear adopts one-dimensional probe sampling mechanism when detecting on the gear measuring center. Due to the sensitive direction of one-dimensional probe is inconsistent with the definition direction of tooth profile normal error， the error calculation process is tedious， and even the error result is inaccurate， which can not truly reflect the machining shape of the actual tooth profile. For this， a closed reconstruction method is proposed and it is applied to the error detection process of RV cycloidal gear， which can not only accurately obtain the machining error of any point of cycloid gear tooth profile， but also the error result can reflect the actual shape of tooth profile. Based on the closed curve reconstruction theory， using the characteristics of the periodic extension of the closed curve， the nodal vector and control vertex of the head and end points are determined， and the reconstructed tooth profile is completely closed and continuous at the closed point. On this basis， an error calculation model is established， and the real tooth profile error is calculated. The practicality and effectiveness of this method are verified by comparison of examples， which provides data basis for subsequent finishing processing.

Infectious bone defects (IBD) remain a major problem in orthopedics in clinical settings. For IBD repair, implants possessing multiple functions such as osseointegration and antibacterial activity are in demand. This study aims to develop a surface-modified titanium (Ti) implant (MTi/Ag/CaP) with osseointegration and antibacterial functions for IBD repair. The pure Ti implant is printed using a selective laser melting technique, and a two-layer hierarchical structure is formed on its surface using a one-step micro-arc oxidation (MAO) approach. The outer layer is an apatite-like material decorated with Ag nanoparticles, whereas the inner layer is porous TiO2. In vitro experiments show that the MTi/Ag/CaP implant can effectively eliminate and inhibit the adhesion and proliferation of bacteria over a long period time while promoting MG-63 cell adhesion, proliferation, and osteogenic differentiation. In vivo experiments further reveal that the MTi/Ag/CaP implant produces more mineralized bone tissue than non-treated samples and interlocks closely with the bone tissue after 8 weeks. The one-step MAO modification developed in this study is simple, efficient, and environment-friendly, which demonstrates great potential as a promising approach for providing advanced biomedical materials in orthopedic applications, including for the prevention and treatment of IBDs.

ABSTRACT MicroRNA-137 (miR-137) has recently emerged as an osteogenic regulator in several cell lines. This study aimed to identify the function of miR-137 on the crosstalk between leucine rich repeat containing G protein-coupled receptor 4 (LGR4) and receptor activator of nuclear factor-κB ligand (RANKL), thus unveiling the critical role of LGR4-RANKL interplay in the osteogenic differentiation of human adipose-derived mesenchymal stem cells (hASCs). By examining the osteogenic capacity and possible downstream genes expression with miR-137 overexpression/knockdown, we found that miR-137 downregulated LGR4 while upregulating RANKL. According to the results of dual-luciferase reporter assay, LGR4 was validated as a direct target of miR-137. Surprisingly, a negative relationship between LGR4 and RANKL was confirmed by the knockdown of these two genes. Furthermore, RANKL inhibitor could alleviate or reverse the inhibitory effects on osteogenesis generated by LGR4 knockdown. Collectively, this study indicated that miR-137-induced a negative crosstalk between LGR4 and RANKL that could contribute to the osteogenic regulation of hASCs and provide more systematic and in-depth understanding of epigenetic modulation by miR-137.

Changes in the mechanical properties of single cells are related to the physiological state and fate of cells. The construction of cell constitutive equations is essential for understanding the material characteristics of single cells. With the help of atomic force microscopy, bio-image processing algorithms, and other technologies, research investigating the mechanical properties of cells during static/quasi-static processes has developed rapidly. A series of equivalent models, such as viscoelastic models, have been proposed to describe the constitutive behaviors of cells. The stress-strain relations under dynamic processes are essential to completing the constitutive equations of living cells. To explore the dynamic mechanical properties of cells, we propose a novel method to generate a controllable dynamical compression shear coupling stress on living cells. A CFD model was established to visualize this method and display the theories, as well as assess the scope of the application. As the requirements or limitations are met, researchers can adjust the details of this model according to their lab environment or experimental demands. This micro-flow channel-based method is a new tool for approaching the dynamic mechanical properties of cells.

Heat tolerance (HT) of rice at anthesis is a key trait that ensures high and stable yields under heat stress. Finding the quantitative trait loci (QTLs) and gene loci controlling HT is crucial. We used relative spikelet fertility (RSF) as a measure of HT. The phenotypic values of RSF in 173 rice accessions were investigated in two environments and showed abundant variations. We performed a genome-wide association study on RSF using 1.2 million single nucleotide polymorphisms (SNPs). Five QTLs were significantly associated with RSF were identified, four were found in previously reported QTLs/genes, and one was novel. The novel QTL qRSF9.2 was mapped into the 22,059,984-22,259,984 bp region, which had 38 positional candidate genes. By combining the linkage disequilibrium analysis, the QTL region was narrowed to 22,110,508–22,187,677 bp, which contained 16 candidate genes. Among them, only gene LOC_Os09g38500 contained nonsynonymous SNPs that were significantly associated with RSF. In addition, accessions with large and small RSF values had corresponding respective high and low gene expression levels. Furthermore, the RSF of the CC allele was significantly higher than that of the TT allele. Hap 2 and Hap 3 can increase heat tolerance by 7.9 and 11.3%, respectively. Our results provide useful information that recommends further cloning of qRSF9.2 and breeding heat-tolerant rice varieties by marker-assisted selection.

This paper deployed a network-based computational content analysis approach to uncover the major themes and targeted stakeholder groups presented in the top leadership’s corporate social responsibility (CSR) reports’ introductory letters for eleven major global vehicle manufacturers for the period 2018-2020. Themes were based on the 3Ps of sustainability (people, planet, and profit), basic busi­ness practices (economic, legal, ethical, and philanthropic) in the context of CSR, time orientation of the themes whether short- or long- term, and identified target­ed stakeholder groups. This study is unique in that the extant literature reveals no research examining CSR disclosure in the automobile industry from both a sus­tainable goal-directed and practices perspective incorporating potential influenc­es of the COVID-19 pandemic. Results revealed that some vehicle manufacturers focused on investor and economic activities while others communicated a general social responsibility message. During 2020, greater emphasis was placed on in­vestors and somewhat less on society in general. Findings suggest the need for a more balanced representation geared toward addressing pandemic and post-pan­demic challenges as well as traditional automotive manufacturing considerations.

Background: Patients with diabetes mellitus (DM) are considered to increase the risk of thrombosis and bleeding. However, whether DM is an independent risk factor for events in patients anticoagulated with bivalirudin during elective percutaneous coronary intervention (PCI) is not clear. Methods: Patients anticoagulated with bivalirudin during elective PCI from January 2017 to August 2018 in 3 centers were enrolled. The primary endpoint of thrombotic events was major adverse cardiac and cerebrovascular events (MACCE, including all-cause death, myocardial infarction, ischemic revascularization, stent thrombosis, and stroke); the primary endpoint of bleeding events was Bleeding Academic Research Consortium (BARC) 2, 3 or 5 bleeding. Results: 1152 patients were finally enrolled. After one-year follow-up, 89 (7.7%) MACCE and 21 (1.8%) BARC 2, 3 or 5 bleeding occurred. Multivariate Cox regression analysis showed DM was not an independent risk factor for MACCE (hazard ratio [HR]: 1.029, 95% confidence interval [CI]: 0.674-1.573, P = .893), but peripheral artery disease (PAD) history (HR: 2.200, 95%CI: 1.290-3.751, P = .004) was an independent risk factor for MACCE. DM was not an independent risk factor for BARC 2, 3 or 5 bleeding (HR: 0.732, 95%CI: 0.293-1.831, P = .505), but PAD history (HR: 3.029, 95%CI: 1.102-8.332, P = .032) and low hemoglobin level (HR = 0.972, 95%CI: 0.947-0.998, P = .036) were independent risk factors for BARC 2, 3 or 5 bleeding. Conclusions: DM was not an independent risk factor for one-year thrombotic and bleeding events in patients anticoagulated with bivalirudin during elective PCI. More attention should be paid to PAD history and hemoglobin level to identify high-risk patients.

Background: Bivalirudin reduces ischemic and hemorrhagic events in patients undergoing primary percutaneous coronary intervention (PCI), but the safety and efficacy for such individuals are unclear. Our aim was to evaluate the long-term safety and efficacy of bivalirudin in patients undergoing elective PCI. Methods: We examined 957 patients with bivalirudin anticoagulation and 1713 patients with unfractionated heparin (UFH) anticoagulation with and without glycoprotein IIb/IIIa inhibitors (GPI). The primary endpoint was net adverse clinical events (NACE), a composite of death, myocardial infarction, revascularization, stent thrombosis, stroke, and bleeding. The secondary endpoints were bleeding and major adverse cardiovascular and cerebrovascular events (MACCE). Results: In one year of follow-up, 307 (11.5%) NACEs, 72 (2.7%) bleedings, and 249 (9.3%) MACCEs occurred. Statistically, patients with bivalirudin anticoagulation had less NACE [hazard ratio (HR): 0.75, 95% confidence interval (CI): 0.58–0.96, p = 0.021] and bleeding (HR: 0.58, 95% CI: 0.34–0.99, p = 0.045) but not less MACCE, than did those with UFH anticoagulation. Furthermore, the risk of bleeding in the bivalirudin group was lower than in the UFH with GPI group (p = 0.001) but not lower than in the group of UFH without GPI (p = 0.197). Conclusions: In patients who undergo elective PCI, the use of bivalirudin significantly decreased the risk of NACE and bleeding without increasing the risk of MACCE; the reduction of bleeding risk with bivalirudin was mainly attributed to the presence of GPIs in the UFH group.

A selective laser-melted Al–Mn–Sc alloy with 99.9% relative density has been obtained in this work through systematic process optimization. The as-fabricated specimen had the lowest hardness and strength, but the highest ductility. The aging response has shown that 300 °C/5 h is the peak aged condition, and it had the highest hardness, yield strength, ultimate tensile strength, and elongation at fracture. Such a high strength was attributed to the uniformly distributed nano-sized secondary Al3Sc precipitates. A further increase in aging temperature to 400 °C resulted in an over-aged condition, which contained a reduced volume fraction of secondary Al3Sc precipitates and resulted in a reduced strength.

Abstract Heart failure (HF) with preserved ejection fraction (HFpEF) is a leading cause of hospitalizations and mortality when diagnosed at the age of ≥ 65 years. HFpEF represents multifactorial and multisystemic syndrome and has different pathophysiology and phenotypes. Its diagnosis is difficult to be established based on left ventricular ejection fraction and may benefit from individually tailored approaches, underlying age-related changes and frequent comorbidities. Compared with the rapid development in the treatment of heart failure with reduced ejection fraction, HFpEF presents a great challenge and needs to be addressed considering the failure of HF drugs to improve its outcomes. Further extensive studies on the relationships between HFpEF, aging, and comorbidities in carefully phenotyped HFpEF subgroups may help understand the biology, diagnosis, and treatment of HFpEF. The current review summarized the diagnostic and therapeutic development of HFpEF based on the complex relationships between aging, comorbidities, and HFpEF.

Brassica napus L. (rapeseed) is one of the most important oil crops with large cultivated area in China. Seed size and seed weight play crucial roles for yield and harvest. In this study, a type of 15 bp-deletion in BnaGRF7.C02 coding region was identified through sequence alignment of BnaGRF7.C02 in 42 rapeseed varieties, and association analysis indicated that the 15 bp-deletion was related to the rapeseed Thousand-Seed Weight (TSW) phenotype. Furthermore, we developed two InDel markers to identify this 15 bp InDel. The tissue-specific expression patterns showed that BnaGRF7.C02 prominently expressed in the late stage of seed development. These findings may assist in InDel markers-based breeding efforts to select higher TWS varieties and improve the crop yield of B. napus.

Abstract In inertial confinement fusion, quantitative and high-spatial resolution ( $$< 10\,\upmu $$ < 10 μ m) measurements of the X-rays self-emitted by the hotspot are critical for studying the physical processes of the implosion stagnation stage. Herein, the 8 ± 0.39-keV monochromatic X-ray distribution from the entire hotspot is quantitatively observed in 5- $$\upmu $$ μ m spatial resolution using a Kirkpatrick–Baez microscope, with impacts from the responses of the diagnosis system removed, for the first time, in implosion experiments at the 100 kJ laser facility in China. Two-dimensional calculations along with 2.5% P2 drive asymmetry and 0.3 ablator self-emission are congruent with the experimental results, especially for the photon number distribution, hotspot profile, and neutron yield. Theoretical calculations enabled a better understanding of the experimental results. Furthermore, the origins of the 17.81% contour profile of the deuterium-deuterium hotspot and the accurate Gaussian source approximation of the core emission area in the implosion capsule are clarified in detail. This work is significant for quantitatively exploring the physical conditions of the hotspot and updating the theoretical model of capsule implosion.

Goal-oriented movement is a fundamental animal behaviour. Here, the authors show that neurons in the superior colliculus project to the substantia nigra pars compacta, regulating dopaminergic signaling and specifically appetitive locomotion in mice.

The compilation of technology lists addressing climate change has a guiding effect on promoting technological research and development, demonstration, and popularization. It is also crucial for China to strengthen ecological civilization construction, achieve the carbon emission peak and carbon neutrality target, and enhance global climate governance capabilities. This study first proposes the existing classification outline of the technology promotion lists, technology demand lists, and future technology lists. Then, different methodologies are integrated on the basis of the existing outline of four technology lists: China’s existing technological promotion list for addressing climate change, China’s demand list for climate change mitigation technology, China’s key technology list for addressing climate change, and China’s future technology list for addressing climate change. What’s more, core technologies are analyzed in the aspects of technology maturity, carbon reduction cost, carbon reduction potential, economic benefits, social influence, uncertainty, etc. The results show that: key industries and sectors in China already have relatively mature mitigation/adaptation technologies to support the achievement of climate change targets. The multi-sectoral system of promoting climate-friendly technologies has been established, which has played an active role in tackling climate change. Currently, climate technology needs are concentrated in the traditional technology and equipment upgrading, renewable energy technology, and management decision-making support technology. The key technologies are concentrated in 3 major areas and 12 technological directions that urgently need a breakthrough. For carbon emmission peak and nentrality, carbon depth reduction and zero carbon emissions and geoengineering technology (CDR and SRM) have played an important role in forming the structure of global emissions and achieving carbon neutrality in the future. Thus, the uncertainty assessment for the comprehensive technology cost-effectiveness, technology integration direction, technical maturity, ethics and ecological impacts is supportive to the national technology strategy. Finally, the presented study proposes several policy implications for medium- and long-term technology deployment, improving technology conversion rate, promoting the research and development of core technologies, and forming a technology list collaborative update and release mechanism.

Abstract Background Lung adenocarcinoma (LUAD) is one of the most common types in the world with a high mortality rate. Despite advances in treatment strategies, the overall survival (OS) remains short. Our study aims to establish a reliable prognostic signature closely related to the survival of LUAD patients that can better predict prognosis and possibly help with individual monitoring of LUAD patients. Methods Raw RNA-sequencing data were obtained from Fudan University and used as a training group. Differentially expressed genes (DEGs) for the training group were screened. The univariate, least absolute shrinkage and selection operator (LASSO), and multivariate cox regression analysis were conducted to identify the candidate prognostic genes and construct the risk score model. Kaplan–Meier analysis, time-dependent receiver operating characteristic (ROC) curve were used to evaluate the prognostic power and performance of the signature. Moreover, The Cancer Genome Atlas (TCGA-LUAD) dataset was further used to validate the predictive ability of prognostic signature. Results A prognostic signature consisting of seven prognostic-related genes was constructed using the training group. The 7-gene prognostic signature significantly grouped patients in high and low-risk groups in terms of overall survival in the training cohort [hazard ratio, HR = 8.94, 95% confidence interval (95% CI)] [2.041–39.2]; P = 0.0004), and in the validation cohort (HR = 2.41, 95% CI [1.779–3.276]; P

Against a background of promoting the industrialization of higher education in Macau due to COVID-19's damage to the territory's major industry—gambling, the present study adopted phenomenological psychology to explore teachers' lived experience of being pedagogical in a university with a neoliberal vision and mission. Using a general structure, the findings revealed that teachers encountered challenges being pedagogical. These challenges emerged not only due to the university's corporate management, but more importantly because of a shift in perceptions—where students became like customers and teachers became self-interested—which made pedagogical relationships difficult to establish. Furthermore, teachers were found to develop negative emotions when their pedagogical actions or intentions conflicted with neoliberalism. The findings suggest that pedagogy in higher education is being challenged and transformed.

BackgroundCurrently, no second-line systemic treatment regimen has been recommended in advanced biliary tract cancer (BTC). Cumulative clinical evidence showed that systemic treatment with tyrosine kinase inhibitors (TKIs) in combination with immunotherapy may shed light on the dim clinical outcome in advanced BTC.ObjectiveThe aim of this study is to evaluate the anticancer efficacy of lenvatinib plus programmed cell death protein-1 (PD-1) antibody in patients with BTC who progressed after first-line cisplatin/gemcitabine (CisGem) chemotherapy.MethodsPatients with advanced BTCs who progressed after CisGem were recruited. A combination regimen of lenvatinib (8/12 mg daily) plus PD-1 antibody (200/240 mg injection every 3 weeks) was prescribed. Clinicopathological information and therapeutic outcome, including tumor subtypes, biomarkers, treatment duration, adverse events (AE), progression-free survival (PFS), and overall survival (OS), were recorded and estimated.ResultsA total of 351 patients with BTCs were reviewed and 74 were recruited eventually: 35 had intrahepatic cholangiocarcinoma (47.3%), 4 had extrahepatic cholangiocarcinoma (5.4%), and 35 had gallbladder cancer (47.3%). The median administered cycles of PD-1 antibody were 6.43 (95% CI: 5.83–7.04) cycles, and the median duration of lenvatinib medication was 21.0 weeks (95% CI: 18.04–23.93). Twenty-eight patients (37.83%) experienced detectable objective response per RECIST1.1 within a median follow-up duration of 15.0 months. The objective response rate (ORR) was 20.27% (95% CI: 10.89%–29.65%), and the disease control rate (DCR) was 71.62% (95% CI: 61.11%–82.14%). The median PFS and OS were 4.0 months (95% CI: 3.5–5.0) and 9.50 months (95% CI: 9.0–11.0), respectively. Seventy-three patients (98.64%) reported AEs and 39 (52.70%) experienced ≥grade 3 AEs. In subgroup analyses, tumoral PD-L1 expression ≥50% and tumor mutation burden (TMB) ≥2.5 Muts/Mb were associated with prolonged PFS.ConclusionLenvatinib plus PD-1 antibody treatment shows an active trend towards improving survival in patients with advanced BTCs after failure with CisGem chemotherapy. The treatment-related AEs are worthy of attention and are manageable.

In implosion experiments, bremsstrahlung radiation ratios of broad-energy-band x-ray emission intensities (sampled by Ross pair) and narrow-energy-band x-ray emission intensities (sampled by multilayer) are typically used to extract the hotspot electron temperature. The latter method could potentially be more accurate because it does not require any additional theoretical arithmetic. However, the boundary conditions of the energy band, drastic influence on the measured electron temperature resulting from response differences of recording devices in the energy band, evident impact from uncertainties of the detector aiming, and coordinate interrelations for the two narrow-energy-band x-ray images have not been explored. These problems should be overcome to obtain the accurate hotspot electron temperature using the narrow-energy-band x-ray emission intensities method. This study solves the problems indicated above by exploring a diagnosis technique to extract the accurate hotspot electron temperature. In particular, we determine that the effect of the response differences and uncertainties could be ignored when the width of the sampled narrow energy band is approximately ±0.5 keV in the linear spectrum response regions of the imaging plate, and the reflectivity of the multilayer is uniform and constant in that energy band and the viewing field of the detector (≥±110 µm). This study is the first to consider the linear spectrum response of the imaging plate in different energy regions, eliminating the effect of the response differences. Finally, the maximal emission intensities in the two recorded-energy-band x-ray images can be used for coordinate interrelation.

Traumatic brain injury (TBI), which is mainly caused by impact, often results in chronic neurological abnormalities. Since the pathological changes in vivo during primary biomechanical injury are quite complicated, the in-depth understanding of the pathophysiology and mechanism of TBI depends on the establishment of an effective experimental in vitro model. Usually, a bomb explosive blast was employed to establish the in vitro model, while the process is complex and unsuitable in the lab. Based on water-hammer, we have developed a device system to provide a single dynamic compression stress on living cells. A series of amplitude (∼5.3, ∼9.8, ∼13.5 MPa) were generated to explore the effects of dynamic compression loading on primary microglia within 48 h. Apoptosis experiments indicated that primary microglia had strong tolerance to blast waves. In addition, the generation of intercellular reactive oxygen species and secretory nitric oxide was getting strongly enhanced and recovered within 48 h. In addition, there is a notable release of pro-inflammatory cytokine by microglia. Our work provides a reproducible and peaceable method of loading single dynamic compression forces to cells in vitro. Microglia showed an acute inflammatory response to dynamic loadings, while no significant cell death was observed. This insight delivers a new technological approach that could open new areas to a better understanding of the mechanism of cell blast injuries.

Flag leaf angle (FLA) is an important outcrossing trait affecting the hybrid seed production in rice (Oryza sativa L.). Natural variation of FLA has been reported in rice, but the molecular basis for this variation is largely unknown. In this study, we investigated the phenotypic values of FLA in 353 rice natural accessions in six environments, which indicated that there was abundant phenotypic variation. We performed a genome-wide association study on FLA using 1.3 million single nucleotide polymorphisms (SNPs). A total of six quantitative trait loci (QTLs) were identified significantly associated with FLA, of which five were located in previously reported QTLs/genes and one was novel. We identified two causal gene loci for FLA, namely, OsFLA6 and OsFLA2; OsFLA6 was co-localized with the gene OsLIC. In addition, the accessions with large and small FLA values have corresponding high and low OsFLA6 expressions. OsFLA2TT allele could increase significantly the seed setting percentage in hybrid F1 seed production by field experiment. We also confirmed that the allele OsFLA2TT increased the FLA compared with that of the isogenic line carrying allele OsFLA2CC by transgenic complementation experiment. The allele frequencies of OsFLA6GGand OsFLA2TT decreased gradually with an increase in latitude in the Northern Hemisphere. Our results should facilitate the improvement of FLA of parents of hybrid rice.

In this study, fluorinated liquid immersion cooling as a new cooling scheme has been tested and discussed for cooling the 18650 lithium-ion battery (LIB). SF33, with the boiling point of 33.4 °C, is chosen as the liquid for the immersion cooling. Comparison of the SF33 immersion cooling and forced air cooling (FAC) for the 18650 LIB under 2C, 4C and dynamic load conditions are made. It is found that the immersion cooling better cools the battery under all these conditions. Under 4C discharging, the maximum cell temperature rise is 14.06 °C for the FAC, while is 4.97 °C for the SF33 immersion cooling. As the temperature of SF33 basically governs the cell temperature, the SF33 temperature should not be too low. This study demonstrates that the LIB has non-negligible power losses under SF33 temperature of 10 °C and 15 °C, compared with the temperatures above 20 °C. Lastly, the two-phase boiling heat transfer mechanisms associated with immersion cooling are discussed with bubble dynamics analysis. It is found under a higher C rate, more aggressive boiling heat transfer is induced. The battery temperature is controlled to be below 34.5 °C even under 7C discharging condition.

Platelets play a central role in hemostasis and thrombosis, regulating the occurrence and development of thrombotic diseases, including ischemic stroke. Programmed death ligand 1 (PD-L1) has recently been detected in platelet, while the function of PD-L1 in platelets remain elusive. Our data reveal a novel mechanism for the role of PD-L1 on platelet activation and arterial thrombosis. PD-L1 knockout does not affect platelet morphology, count, and mean volume under homeostasis and without risk of bleeding, which inhibits platelet activation by suppressing outside-in-activation of integrin by downregulating the Caspase-3/GSDME pathway. Platelet adoptive transfer experiments demonstrate that PD-L1 knockout inhibits thrombosis. And the absence of PD-L1 improves ischemic stroke severity and increases mice survival. Immunohistochemical staining of the internal structure of the thrombus proves that PD-L1 enhances the seriousness of the thrombus by inhibiting platelet activation. This work reveals a regulatory role of PD-L1 on platelet activation and thrombosis while providing novel platelet intervention strategies to prevent thrombosis.

Using non-equilibrium molecular dynamics simulations, the kinetic boundary condition (KBC) for direct-contact condensation in two-phase jet and its evaporation and condensation coefficients were studied to solve the Boltzmann equation. The evaporating and reflecting molecular behaviors were studied in detail. The normalized velocity distributions of reflecting molecules in the z-direction before and after reflection fit the Maxwell velocity distribution shifted by two large macroscopic velocities toward and away from the liquid surface owing to the strong net condensation rate. A singular definition of the evaporation coefficient has not been obtained in previous studies. We used a two-boundary method to count the evaporation coefficient and define a parameter to connect our result and the spontaneous evaporation coefficient. The condensation coefficient was studied using the condensation probability and showed larger than the evaporation coefficient in direct-contact condensation states. Both the evaporation and condensation coefficients were not independent of the incoming mass flux. When the incoming mass flux was small, the values of these two coefficients were close to the values under equilibrium states. Based on these results, we constructed the KBC of direct-contact condensation.

BackgroundAge-related cognitive decline (ARCD) is a common condition among older adults, affecting 100 million people worldwide. Traditional Chinese Medicine’s (TCM) constitution is closely related to the occurrence and development of diseases in the elderly population. However, little is known about the relationships between TCM constitution and ARCD in the super-aged population. The present study aimed to investigate the relationships between the TCM constitution and ARCD in Chinese centenarians and to explore the application of the constitution to prevent ARCD in the elderly population.MethodsEach participant underwent a standardized epidemiological investigation and physical examination, based on the China Hainan Centenarian Cohort Study. Data on the demographic characteristics and TCM constitution were collected using structured questionnaires.ResultsThe present study included 636 centenarians aged 100–116 years. The prevalence of ARCD was 87.7% (n = 558 centenarians). In multiple linear regression analysis, an inverse relationship between Qi depression and Mini-Mental State Examination scales was significant after controlling for a wide range of other factors (P < 0.05). In multiple logistic regression analysis, Qi depression was positively associated with ARCD after full adjustment (P < 0.05).ConclusionAs the first study in the world, the present study provides strong epidemiological evidence that Qi depression has a significant relationship with ARCD in Chinese centenarians, and regulating Qi depression may be a valuable method to prevent and treat ARCD in the elderly population.

Abstract Background Oncopanel genomic testing, which identifies important somatic variants, is increasingly common in medical practice and especially in clinical trials. Currently, there is a paucity of reliable genomic reference samples having a suitably large number of pre-identified variants for properly assessing oncopanel assay analytical quality and performance. The FDA-led Sequencing and Quality Control Phase 2 (SEQC2) consortium analyze ten diverse cancer cell lines individually and their pool, termed Sample A, to develop a reference sample with suitably large numbers of coding positions with known (variant) positives and negatives for properly evaluating oncopanel analytical performance. Results In reference Sample A, we identify more than 40,000 variants down to 1% allele frequency with more than 25,000 variants having less than 20% allele frequency with 1653 variants in COSMIC-related genes. This is 5–100× more than existing commercially available samples. We also identify an unprecedented number of negative positions in coding regions, allowing statistical rigor in assessing limit-of-detection, sensitivity, and precision. Over 300 loci are randomly selected and independently verified via droplet digital PCR with 100% concordance. Agilent normal reference Sample B can be admixed with Sample A to create new samples with a similar number of known variants at much lower allele frequency than what exists in Sample A natively, including known variants having allele frequency of 0.02%, a range suitable for assessing liquid biopsy panels. Conclusion These new reference samples and their admixtures provide superior capability for performing oncopanel quality control, analytical accuracy, and validation for small to large oncopanels and liquid biopsy assays.

Cholinergic neurons may transmit information via fast synaptic, point-to-point signaling or diffuse, slow extra-synaptic signaling. The authors show that ACh from a single vesicle triggers synchronous miniature currents in two neurons, showing that ACh can spread significant distances to drive rapid ‘synaptic’ signals.

The communication range of magnetic-induction (MI) technology in extreme environments such as underwater or underground is limited by the dipole-like attenuation behavior of the magnetic field as well as the eddy current induced loss in conductive media, and therefore a highly sensitive receiver is generally required. In this work, we propose the use of a highly sensitive superconducting quantum interference device (SQUID) in MI communication and try to provide a comprehensive investigation on developing a SQUID-based receiver for practical MI applications. A portable receiver scheme integrating a SQUID sensor and a coil-based flux transformer was proposed. The high sensitivity and long-range communication capability of the proposed receiver was experimentally demonstrated by spectroscopic measurements and reception experiments on a receiver prototype. Based on the experimental demonstrations, the sensitivity optimization of the proposed scheme was further investigated by simulation studies, which suggest that a communication distance exceeding 100 m and a channel capacity of ∼20 kb/s in underwater environment could be achieved based upon the optimization of the developed prototype. The results presented in this work have highlighted the potential of deploying SQUID sensors for long-range MI applications in extreme environments.

In order to fabricate homogeneous large-scale Ti-5Al-5V-5Mo-3Cr (Ti-5553) alloy bulk with fine and equiaxial β grain, we performed a series of multi-axial α + β field forging with 62 forging cycles on the large-scale Ti-5553 billet by using 12.5 MN high-speed hydraulic press. The β-annealed microstructure was the starting microstructure of the billet. After the 6th forging cycle, β grain deformed dramatically, and the grain-boundary network developed within the irregular β grain. As the forging cycle increased to 44, the volume fraction of the fine and equiaxial β grain that is less than 20 μm, which is caused by dynamic recrystallization, increased gradually. However, the incomplete dynamic recrystallization region within the original β grain could not be eliminated. As the forging cycle further increased, the volume fraction of the fine and equiaxial β grain did not increase. In contrast, the abnormal grain growth of the β phase occurred during 50th~62nd forging cycle. Here, we attribute the formation of the incomplete dynamic recrystallization region and the abnormal grain growth of the β phase to the high deformation rate of the α + β forging. The refining behavior of β grain and the abnormal coursing β grain, which is found during the multi-cycle multi-axial forging of large-scale Ti-5553 alloy billet, are seldom reported in the isothermal compression of small-scale Ti-5553 alloy specimen. The findings of the paper are instructive for improving the sub-transus forging strategy that is used to fabricate the large-scale homogeneity Ti-5553 alloy billet with fine and equiaxial β grain.

Abstract The impact of the COVID-19 pandemic on clinically stable older patients with psychiatric disorders is unclear. This study examined the prevalence of depressive and anxiety symptoms, and their associations with quality of life (QOL) in clinically stable older patients with psychiatric disorders during the COVID-19 pandemic. This was a multicenter, cross-sectional study. Depressive and anxiety symptoms, insomnia, pain, and QOL were assessed with standardized instruments. A total of 1063 patients were included. The prevalence of depressive and anxiety symptoms, and combined depressive and anxiety symptoms were 62.3% (95%CI = 59.4–65.2%), 52.4% (95%CI = 49.3–55.4%), and 45.9% (95%CI = 42.9–48.9%), respectively. Patients with depressive and anxiety symptoms had significantly lower QOL than those without (P

In order to understand the role of formaldehyde in living systems, real-time monitoring is required. Here the authors report a genetically encoded, reaction-based formaldehyde sensor (FAsor) that enables visualisation of formaldehyde in mammalian cells and tissues.

Abstract Gas bearings, which have the advantages of low frictional resistance and power loss, high rotational speed and high temperature operation, and long life, are more suitable than are traditional liquid lubricated bearings because of their high precision, high rotational speed, and special condition support. However, the problem of starting a closed-cycle compression system with gas bearings still needs to be solved for practical application. Thus, a new start-up method for a closed-cycle compression system with aerostatic gas bearings is proposed in this paper. Further, this paper presents a numerical simulation and experimental investigation of the method’s feasibility and characteristics during the start-up process when the gas tank’s initial pressure is fixed. The results show that the gas tank volume is approximately directly proportional to the start-up time allowable, and a gas tank volume sufficiently small, which not only ensures the feasibility of start-up, but also affects other components only slightly, can be obtained. A perfect combination of radial and axial loads also can be achieved to make the start-up time allowable as long as possible. R134a is a better choice for the working medium than is air, as the start-up time allowable is longer, which leads to a smaller gas tank. This research proposes a new start-up method for a closed-cycle compression system with aerostatic gas bearings which has sufficient load capacity to support system during the start-up method.

Abstract Background The pattern of fatigue in older psychiatric patients during the COVID-19 outbreak was unknown. This study examined the prevalence of fatigue and its association with overall quality of life (overall QOL) in clinically stable older patients with psychiatric disorders during the COVID-19 outbreak. Methods This was a multicenter, cross-sectional study. Fatigue, depressive symptoms, pain, insomnia symptoms, and overall QOL were assessed with standardized instruments. Results A total of 1063 patients were recruited. The prevalence of fatigue was 47.1% (95%CI: 44.1–50.1%). An analysis of covariance revealed that overall QOL was significantly lower in patients with fatigue compared to those without (P = 0.011). A multiple logistic regression analysis revealed that more severe depressive symptoms (OR = 1.15, P

To derive a unified calculation model for gear cross-section area suitable for arbitrary tooth profile. Firstly， based on the external conjugate relation between two identical gear， it is analyzed that cross-section area of gear is composed of pitch circle area， plus conjugated area， and minus minimum top gap area. Secondly， based on the geometric relationship of conjugate profile， the simplest calculation formula without error of the conjugated area and simplified calculating method of minimum top gap area adopts partial hob are given. Finally， example calculation and analysis of gear cross-section area with involute profile are carried out. All results show that the pitch circle area is much larger than conjugated area and minimum top gap area， but calculation method of minimum top gap area determined calculation accuracy of cross-section area， the theory error of gear cross-section area is 0.24%，which could be used in high precision calculation of gear cross-section area. It is concluded that the conjugated area formula is suitable for volume utilization coefficient calculation in arbitrary tooth profile without error for pump.

Cadmium (Cd) is a highly toxic metal pollutant that can endanger the life and health of animals. Toll-like receptor 4 (TLR4) can result in testicular cell damage by positively regulating mitogen-activated protein kinase (MAPK)/nuclear factor-kappaB (NF-κB) signaling pathway. Meanwhile, Testosterone (T) synthesis disorder can affect sexual behavior. However, the harmful influence of Cd on animal sexual behavior during its growth and development and the role of TLR4/MAPK/NF-κB signaling pathway in testicular cell damage and testosterone production remained poorly understood. Forty-two-day-old male piglets were fed with diets that contained CdCl2 (20 mg Cd/kg) for 40 days to explore the toxic effects of Cd on sexual behavior. The results showed that Cd activated TLR4, promoted MAPK (p-ERK, p-JNK, and p-p38)/NF-κB expression, induced apoptosis (Caspase-3, Cleaved Caspase3, Bax, Cyt-c, and Caspase-9 expression increased, but Bcl-2 expression decreased) and necroptosis (MLKL, RIPK1, and RIPK3 expression increased) in piglet testis. In addition, Cd exposure decreased mRNA expression of STAR, CYP11A1, 3β-HSD, CYP17A1, and 17β-HSD of testis and the concentrations of T and thyroid-stimulating hormone (TSH). Both the mRNA and protein expression levels of the major genes in TLR4/MAPK/NF-κB signaling pathway, apoptosis signaling pathway, and necroptosis signaling pathway increased significantly and the expression levels of testosterone decreased gradually in pig Leydig cells cultured in vitro after being treated with different concentrations of Cd. Moreover, Cd reduced sexual behavior (the parameters of sniffing, chin resting, and mounting decreased) in piglets. In conclusion, Cd induced testicular cell damage via TLR4/MAPK/NF-κB signaling pathway leading to testosterone synthesis disorder and sexual behavior reduction in piglets.

Summary: Reducing the friction and wear of dynamic interfaces has been a constant endeavor in the field of sustainability. Lubricants with two-dimensional atomic materials are operative frameworks proposed as promising candidates: they can together generate both a boundary tribofilm and a liquid hydrodynamic film in the interfacial domain. However, a quantitative characterization of the film formation and their coupling behaviors in the finite domain is lacking. Here, we report the coupling effect of tribofilms and hydrodynamic films regulated by typical representatives of two-dimensional material family (graphene, hBN, MoS2, and WS2). The anti-wear properties of the interfaces are attributed to the behavior of the tribofilm, whereas the anti-friction properties of the interfaces are attributed to the viscosity behavior of the hydrodynamic film. This study provides an understanding of the intrinsic coupling mechanism of a tribofilm and a hydrodynamic film and a possible strategy for the design of interfacial lubricating systems.

Objective: Age-related hearing loss (ARHL) and age-related cognitive decline (ARCD) are leading causes of disability in older adults. ARHL may increase ARCD risk and cause depression development. This study aimed to explore the associations of ARHL with ARCD and depression in Chinese centenarians and oldest-old adults. Methods: A household survey was conducted on 859 centenarians and oldest-old adults residing in 16 cities and counties in China. Basic information was collected using interview questionnaires, physical examinations, and blood tests conducted by systematically trained local doctors and nurses. Results: In total, 501 (58.3%), 649 (75.6%), and 211 (24.6%) participants had ARHL, ARCD, and depression, respectively. The prevalence of ARCD and depression was significantly higher in participants with ARHL than in those without ARHL (all p

Anatomical and physiological compartmentalization of neurons is a mechanism to increase the computational capacity of a circuit, and a major question is what role axonal compartmentalization plays. Axonal compartmentalization may enable localized, presynaptic plasticity to alter neuronal output in a flexible, experience-dependent manner. Here, we show that olfactory learning generates compartmentalized, bidirectional plasticity of acetylcholine release that varies across the longitudinal compartments of Drosophila mushroom body (MB) axons. The directionality of the learning-induced plasticity depends on the valence of the learning event (aversive vs. appetitive), varies linearly across proximal to distal compartments following appetitive conditioning, and correlates with learning-induced changes in downstream mushroom body output neurons (MBONs) that modulate behavioral action selection. Potentiation of acetylcholine release was dependent on the CaV2.1 calcium channel subunit cacophony. In addition, contrast between the positive conditioned stimulus and other odors required the inositol triphosphate receptor, which maintained responsivity to odors upon repeated presentations, preventing adaptation. Downstream from the MB, a set of MBONs that receive their input from the γ3 MB compartment were required for normal appetitive learning, suggesting that they represent a key node through which reward learning influences decision-making. These data demonstrate that learning drives valence-correlated, compartmentalized, bidirectional potentiation, and depression of synaptic neurotransmitter release, which rely on distinct mechanisms and are distributed across axonal compartments in a learning circuit.

High concentration of blood ammonia can affect the uterus receptivity and decrease fecundity in dairy cow. Melatonin can reduce reactive oxygen species (ROS) level and has antioxidant and anti-inflammatory effects. However, it is not clear whether melatonin can alleviate ammonia-induced apoptosis of endometrial epithelial cell (EEC) and reduced uterus receptivity. The bovine EEC were treated with ammonium chloride and/or melatonin. Cell viability, apoptosis, oxidative stress and mitochondrial membrane potential were measured and the expression of apoptosis-related genes (p53, Cyt-c, Bax, Bcl-2, caspase-8, caspase-9 and caspase-3), uterus receptivity related genes (VEGF, LIF and EGF) and inflammatory factors (TLR-4, IL-6 and NF-κB) were detected. In addition, the expression of VEGF was detected after adding NF-κB inhibitor (40 μM) and IL-6 (1 ng/mL and 50 ng/mL). The results showed that ammonia significantly increased intracellular ROS level, mRNA and protein expression of Bax, p53, Cyt-c, caspase-9, caspase-8, caspase-3, TLR-4, NF-κB and IL-6, promoted cell apoptosis, while decreased mitochondrial membrane potential, the mRNA and protein expression of VEGF and EGF. Interestingly, melatonin significantly mitigated ammonia-induced changes. However, melatonin could not alleviate ammonia-induced changes of IL-6 and VEGF when NF-κB signal pathway was inhibited. The addition of IL-6 significantly reduced mRNA and protein expression of VEGF. In conclusion, ammonia induced EEC apoptosis through ROS production and activation of mitochondrial apoptosis pathway, and induced inflammatory response through TLR4/NF-κB/IL-6 pathway. Melatonin alleviated EEC apoptosis by inhibiting ROS pathway, and reduced IL-6 expression by inhibiting TLR-4/NF-κB signal pathway, which eventually improved VEGF expression and uterus receptivity in dairy cows.

The relevance of the problem under study is due to the need to study the issue of the features of the formation of the appearance of aircraft equipped with a collective rescue system for passengers and crew. The purpose of the article is to study the collective rescue system for passengers and crew. The leading method for studying this problem is the method of analyzing the conceptual features of aircraft design as part of a collective rescue system (CRS). It is shown that the exclusion of the contact zone of the emergency plane with the ground will allow to qualitatively and quantitatively increase the safety of passengers and crew. The structural decomposition made it possible to identify the place of collective rescue systems in the structure of the aircraft. A procedural decomposition is given, which allows structural assembly of aircraft units and systems. A phased program for studying the problem of implementing collective rescue is given by the example of a light aircraft of vertical takeoff and landing. An example of the implementation of a collective rescue system is shown.

In the work, the process of unsteady contact interaction of rigid stamp and elastic half-space having a recessed cavity of arbitrary geometry and location with a smooth boundary was investigated. Three variants of contact conditions are considered: free slip, rigid coupling, and bonded contact. The method for solving the problem is constructed using boundary integral equations. To obtain boundary integral equations, the dynamic reciprocal work theorem is used. The kernels of integral operators are bulk Green functions for the elastic plane. Because of straight-line approximations of the domain boundaries with respect to the spatial variable and straight-line approximations of the boundary values of the desired functions with respect to time, the problem is reduced to solving a system of algebraic equations with respect to the pivotal values of the desired displacements and stresses at each time interval. One of the axes is directed along the regular boundary of half-space, the second - deep into half-space.

An increase of English for Academic Purposes (EAP) teaching in China has resulted in a surge of EAP textbooks on the market. However, there has been little accompanying interest in how well intercultural issues are handled and presented in these publications. Accordingly, the present study employs Chinese students’ Cultures of Learning (CoL) and contrastive rhetoric (CR) as reflection points in the analysis of the content, production, and consumption of two series of EAP textbooks adapted from overseas textbooks. Findings revealed that intercultural differences are not given due recognition in the textbooks which in some cases can lead to confusion and misunderstanding. Meanwhile, the teachers involved in the study, as users of the other textbook series, were found to treat the textbooks only as a supplementary EAP teaching resource. Moreover, the continued confusion on the part of some of the students involved in the study highlighted the desirability for future textbooks to render intercultural differences in a critical EAP manner.

Abstract In this study, mechanical mechanism analyses of hole cut blasting and in situ hole cut blasting tests using different cutting programs were conducted to investigate the hole cut blasting mechanism under the influence of complicated geological conditions and its blasting excavation effect. The hole cut blasting mechanism was evaluated under the background of medium‐length hole cut blasting test in a typical coal‐rock roadway in Xiayukou coal mine of Hancheng mining area in Western China to improve the blasting excavation efficiency in coal mine roadways. Test results indicated that the rock clamping action is remarkably enhanced when the depth of medium‐length holes, which are impacted by various complicated geological factors, reaches more than 1.8 m under weak coal‐rock mass conditions. At the same time, the antidrag effect is good when double‐wedge cut blasting is selected, and its mitigation of rock clamping action is reflected through the reduction of rock resistance of phase I hole cut blasting. The enhanced blasting effect is embodied by the footage cycle and forming effect of blasting, and the footage cycle of single blasting increases from 1.6 to 2.0 m, thereby indicating its remarkable economic benefits. The results of this study can provide a reference for hole cut blasting design and mechanism study of weak coal‐rock masses under complicated geological conditions.

The present study proposes a time domain model for the Vortex-induced Vibration (VIV) simulation of a catenary riser under the combination of the current and oscillatory flow induced by vessel motion. In this model, the hydrodynamic force of VIV comprises excitation force, hydrodynamic damping and added mass, which are taken as functions of the non-dimensional frequency and amplitude ratio. The non-dimensional frequency is related with the response frequency, natural frequency, lock-in range and the fluid velocity. The relatively oscillatory flow induced by vessel motion is taken into account in the fluid velocity. Considering that the added mass coefficient and the non-dimensional frequency can affect each other, an iterative analysis is conducted at each time step to update the added mass coefficient and the natural frequency. This model is in detail validated against the published test models. The results show that the model can reasonably reflect the effect of the added mass coefficient on the VIV, and can well predict the riser’s VIV under stationary and oscillatory flow induced by vessel motion. Based on the model, this study carries out the VIV simulation of a catenary riser with harmonic vessel motion. By analyzing the bending moment near the touchdown point, it is found that under the combination of the ocean current and oscillatory flow the vessel motion may decrease the VIV response, while increase the excited frequencies. In addition, the decreasing rate of the VIV under vessel surge is larger than that under vessel heave at small vessel motion velocity, while the situation becomes opposite at large vessel motion velocity.

This research concerns itself with increasing the accuracy of random projections used to quickly approximate the inner products of data vectors from a given dataset by adding additional information, namely, adding and storing more extra known vectors to the given dataset and associated information. We show how the variance of estimated inner products is reduced as more vectors are added, how variance reduction is related to the geometry of the dataset and moreover, the asymptotic behaviour of the variance as the number of extra vectors added goes to infinity. We provide the formulae governing the estimate of inner products for adding arbitrarily many extra vectors. Lastly, we demonstrate how to efficiently implement the computations of the estimates by showing we can use pre-computed and stored values for most of the computations. Numerical simulations are conducted to support the analytical results.

Sentence similarity is widely used in various natural language tasks such as natural language inference, paraphrase identification, and question answering. However, a variety of linguistic expressions and ambiguities of words in sentences make it difficult to measure sentence similarity. Many studies show that using local features or global features of a sentence will produce satisfactory sentence representations that can be utilized to measure sentence similarity. Local features reflect the relationships of adjacent words for each sentence and the sequence information of a sentence are usually expressed by global features. However, local features lack abilities to capture sequence information while a small amount of extracted global features is not enough to produce sentence representations with good qualities. In this paper, we propose A Hybrid Model combining Local and Global features into a Siamese Network (HM-LGSN) for sentence similarity calculation. We first propose a new convolution neural network architecture called group convolution neural network to extract the most representative local features (or word semantic features). Then we combine these new features with pre-trained embeddings of words as input to the Bidirectional Gated Recurrent Units to extract global features of sentences. Finally, we select the global features to form sentence representations and calculate sentence similarity through Manhattan distance. The experimental results on SICK, MSRVID, STS-B datasets show that the accuracy of our proposed model is significantly improved by combining local features and global features.

Online aerodynamic parameter estimation plays an important role in compensating control system of aircraft under parameter uncertainties and unknown disturbance. In this paper, stability and control derivatives of aircraft are estimated online via support vector regression-numerical differential(SVR-ND) method. Small-sample real-time flight data reflecting real-time aerodynamic characteristics of aircraft is processed as training samples. For the small-size training samples, SVR technique is used for aerodynamic modeling. To pursue good performance in both computation efficiency and estimation accuracy, offline parameter estimation simulations are performed to select training sample size. It is observed that parameter estimation accuracy is related to the number of training samples and the noise level of samples. After that, an empirical formula is proposed to select training sample size according to results of simulations. To adapt the variation of samples, empirical formulas to tune hyper-parameters of SVR are presented based on the estimation of noise variance of samples. Finally, aerodynamic parameters are obtained by numerical differential in real-time. In a simulated maneuver, the proposed method is applied to online aerodynamic parameter estimation, and a Monte Carlo simulation is carried out to validate the robustness of SVR-ND method. Results indicate that the proposed method could realize accurate and robust estimation of aerodynamic parameters online.

This work investigated the fatigue crack propagation behavior of the 2195-T8 Al-Li alloy with precorroded holes. The microstructure, crack growth path, and the fracture surfaces of the samples with the precorroded holes have been examined with scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), and computed tomography (CT). The characteristics of the crack growth have been analyzed via fracture mechanics by employing the finite element method (FEM). The results showed that the bulk of the fatigue cracks had been initiated from the corrosion pits and corroded discontinuously and precipitated further to become intergranular. Owing to the superposed stress concentration caused by the corrosion pits, the porous region at the bottom of the precorroded hole had affected the crack propagation performance. Crack growth rates were different in multiple positions owing to the difference of KI at crack fronts.

Lignin–carbohydrate complexes (LCCs) are emerging as a new and natural product with pharmacological and nutraceutical potential. It is uncertain, however, whether LCCs have a positive effect on the microbiota of the gut based on the current evidence. Here, the LCC extracted from beechwood (BW-LCC) was used as a substrate for in vitro fermentation. The lignin in BW-LCC consisted of guaiacyl (G) and syringyl (S) units, which are mainly linked by β-O-4 bonds. After 24 h of in vitro fermentation, the pH had evidently declined. The concentrations of acetic acid and propionic acid, the two main short-chain fatty acids (SCFAs), were significantly higher than in the control group (CK). In addition, BW-LCC altered the microbial diversity and composition of gut microbes, including a reduction in the relative abundance of Firmicutes and an increase in the relative abundance of Proteobacteria and Bacteroidetes. The relative abundance of Escherichia coli-Shigella and Bacteroides were the most variable at the genus level. The genes of carbohydrate-active enzymes (CAZymes) also changed significantly with the fermentation and were related to the changes in microbes. Notably, the auxiliary actives (AAs), especially AA1, AA2, and AA3_2, play important roles in lignin degradation and were significantly enriched and concentrated in Proteobacteria. From this study, we are able to provide new perspectives on how gut microbes utilize LCC.