Study on compressive stress-strain relationship of ultra-high performance concrete with coarse aggregates under and after high temperatures

Uniaxial compression tests are conducted on ultra-high performance concrete (UHPC) with different volume fractions of coarse aggregates (0 %, 10 %, 20 %, and 30 %) at temperatures ranging from room temperature to 900°C, both during and after high-temperature exposure. The compressive failure modes and the stress-strain curves of the ultra-high performance concrete with coarse aggregates (CA-UHPC) under and after high temperatures are obtained. A systematic analysis of the key characteristic parameters of the stress-strain curve, including axial compressive strength, elastic modulus, and peak strain, is carried out, and respective temperature-dependent calculation formulas are proposed. Experimental results show that the failure modes under and after high temperatures are similar, both exhibiting shear failure. It is found that both the temperature and the coarse aggregate contents affect the shape of the stress-strain curve. The uniaxial compressive performance of the CA-UHPC under and after high temperatures is compared. Finally, the uniaxial compressive stress-strain relationships of the CA-UHPC under and after high temperatures are established, considering the temperature, coarse aggregate content, and steel fiber content

Angiopoietin-2 impairs collateral artery growth associated with the suppression of the infiltration of macrophages in mouse hindlimb ischaemia

Abstract Background Angiopoietin-2 (Ang-2), a ligand of the Tie-2 receptor, plays an important role in maintaining endothelial cells and in destabilizing blood vessels. Collateral artery growth (arteriogenesis) is a key adaptive response to arterial occlusion. It is unknown whether the destabilization of blood vessels by Ang-2 can affect arteriogenesis and modulate mononuclear cell function. This study aimed to investigate the effects of Ang-2 on collateral artery growth. Methods Hindlimb ischaemia model was produced in C57BL/6 mice by femoral artery ligation. Blood flow perfusion was measured using a laser Doppler perfusion imager quantitative RT-PCR analysis was applied to identify the level of angiogenic factors. Results After the induction of hindlimb ischaemia, blood flow recovery was impaired in mice treated with recombinant Ang-2 protein; this was accompanied by a reduction of peri-collateral macrophage infiltration. In addition, quantitative RT-PCR analysis revealed that Ang-2 treatment decreased monocyte chemotactic protein-1 (MCP-1), platelet-derived growth factor-BB (PDGF-BB) mRNA levels in ischaemic adductor muscles. Ang-2 can lead to macrophage M1/M2 polarization shift inhibition in the ischaemic muscles. Furthermore, Ang-2 reduced the in vitro inflammatory response in macrophages and vascular cells involved in arteriogenesis. Conclusions Our results demonstrate that Ang-2 is essential for efficient arteriogenesis, which controls macrophage infiltration

A programmable topological photonic chip

Controlling topological phases of light has allowed experimental observations of abundant topological phenomena and development of robust photonic devices. The prospect of more sophisticated controls with topological photonic devices for practical implementations requires high-level programmability. Here, we demonstrate a fully programmable topological photonic chip with large-scale integration of silicon photonic nanocircuits and microresonators. Photonic artificial atoms and their interactions in our compound system can be individually addressed and controlled, therefore allowing arbitrary altering of structural parameters and geometrical configurations for the observations of dynamic topological phase transitions and diverse photonic topological insulators. By individually programming artificial atoms on the generic chip, it has allowed comprehensive statistic characterisations of topological robustness against relatively weak disorders, as well as counterintuitive topological Anderson phase transitions induced by strong disorders. Our generic topological photonic chip that can be rapidly reprogrammed to implement multifunctionalities, prototypes a flexible and versatile platform for possible applications across fundamental science and topological technologies

TencentPretrain: A Scalable and Flexible Toolkit for Pre-training Models of Different Modalities

Recently, the success of pre-training in text domain has been fully extended to vision, audio, and cross-modal scenarios. The proposed pre-training models of different modalities are showing a rising trend of homogeneity in their model structures, which brings the opportunity to implement different pre-training models within a uniform framework. In this paper, we present TencentPretrain, a toolkit supporting pre-training models of different modalities. The core feature of TencentPretrain is the modular design. The toolkit uniformly divides pre-training models into 5 components: embedding, encoder, target embedding, decoder, and target. As almost all of common modules are provided in each component, users can choose the desired modules from different components to build a complete pre-training model. The modular design enables users to efficiently reproduce existing pre-training models or build brand-new one. We test the toolkit on text, vision, and audio benchmarks and show that it can match the performance of the original implementations

The <i>Sinocyclocheilus</i> cavefish genome provides insights into cave adaptation

BACKGROUND: An emerging cavefish model, the cyprinid genus Sinocyclocheilus, is endemic to the massive southwestern karst area adjacent to the Qinghai-Tibetan Plateau of China. In order to understand whether orogeny influenced the evolution of these species, and how genomes change under isolation, especially in subterranean habitats, we performed whole-genome sequencing and comparative analyses of three species in this genus, S. grahami, S. rhinocerous and S. anshuiensis. These species are surface-dwelling, semi-cave-dwelling and cave-restricted, respectively. RESULTS: The assembled genome sizes of S. grahami, S. rhinocerous and S. anshuiensis are 1.75 Gb, 1.73 Gb and 1.68 Gb, respectively. Divergence time and population history analyses of these species reveal that their speciation and population dynamics are correlated with the different stages of uplifting of the Qinghai-Tibetan Plateau. We carried out comparative analyses of these genomes and found that many genetic changes, such as gene loss (e.g. opsin genes), pseudogenes (e.g. crystallin genes), mutations (e.g. melanogenesis-related genes), deletions (e.g. scale-related genes) and down-regulation (e.g. circadian rhythm pathway genes), are possibly associated with the regressive features (such as eye degeneration, albinism, rudimentary scales and lack of circadian rhythms), and that some gene expansion (e.g. taste-related transcription factor gene) may point to the constructive features (such as enhanced taste buds) which evolved in these cave fishes. CONCLUSION: As the first report on cavefish genomes among distinct species in Sinocyclocheilus, our work provides not only insights into genetic mechanisms of cave adaptation, but also represents a fundamental resource for a better understanding of cavefish biology. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12915-015-0223-4) contains supplementary material, which is available to authorized users

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

miR‐126‐5p expression in the plasma of patients with sepsis‐induced acute lung injury and its correlation with inflammation and immune function

Abstract Objective This work was implemented to elucidate the miR‐126‐5p expression in the plasma of patients with sepsis‐induced acute lung injury (ALI) and its correlation with inflammation and immune function. Methods The peripheral blood of patients with sepsis‐induced ALI was obtained, and the levels of inflammatory factors (interleukin‐6 [IL‐6], C‐reactive protein [CRP], and procalcitonin [PCT]) were determined. Meanwhile, T lymphocyte subsets (CD3+, CD4+, and CD8+), and immunoglobulins (IgA, IgM, and IgG) were tested. miR‐126‐5p and TRAF6 mRNA expression in plasma was assessed. Receiver operating characteristic (ROC) curve was performed to assess the diagnostic accuracy of miR‐126‐5p in sepsis without ALI and sepsis with ALI. Correlation between miR‐126‐5p expression and clinical indicators was analyzed. The targets of miR‐126‐5p were predicted using the bioinformatics method, and the direct targets were verified through investigations. Results miR‐126‐5p expression in plasma of patients with sepsis‐induced ALI was reduced than that of patients with sepsis without ALI. miR‐126‐5p expression was negatively correlated with IL‐6, CRP, and PCT but positively correlated with IgA, IgM, and IgG as well as CD3+, CD4+, and CD8+ in patients with sepsis‐induced ALI. ROC curve suggested that miR‐126‐5p (AUC: 0.777; 95%CI: 0.689–0.866) could distinguish patients with sepsis with ALI from patients with sepsis without ALI. TRAF6 expression in patients with sepsis‐induced ALI was higher than that in patients with sepsis without ALI. TRAF6 was a target gene of miR‐126‐5p, Conclusion This research highlights that miR‐126‐5p is reduced in the plasma of patients with sepsis‐induced ALI, and miR‐126‐5p relates to systemic inflammation and immune function indicators

Welding Distortion Prediction in 5A06 Aluminum Alloy Complex Structure via Inherent Strain Method

Finite element (FE) simulation with inherent deformation is an ideal and practical computational approach for predicting welding stress and distortion in the production of complex aluminum alloy structures. In this study, based on the thermal elasto-plastic analysis, FE models of multi-pass butt welds and T-type fillet welds were investigated to obtain the inherent strain distribution in a 5A06 aluminum alloy cylindrical structure. The angular distortion of the T-type joint was used to investigate the corresponding inherent strain mechanism. Moreover, a custom-designed experimental system was applied to clarify the magnitude of inherent deformation. With the mechanism investigation of welding-induced buckling by FE analysis using inherent deformation, an application for predicting and mitigating the welding buckling in fabrication of complex aluminum alloy structure was developed

Analysis about Parameters Selection Strategy of ECOM Solar Radiation Pressure Model for BeiDou Satellites

In this paper,the variations of ECOM solar radiation pressure model parameters were analyzed for BeiDou satellites through orbit fitting using 3 years precise ephemeris data. The ECOM parameter selection strategies for the three types of BeiDou satellites were confirmed. Based on the satellite attitude control modes,satellite illumination was theoretically analyzed. We pointed out that solar panels are perpendicular illuminated,and then solar radiation pressure has the periodic component associated with the orbital period when satellite is at orbit-normal attitude control mode. Periodic parameters of D direction need to be added to enhance the ECOM 5 parameters. Orbit determination tests were carried out using MGEX global network data. Tests prove that using ECOM 7 parameters the orbit overlap accuracy improvement could reach up to 50%~80%