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国家会展中心是由主展厅及相关配套建筑组成的特大型会展综合体项目。4个主展厅单体覆盖面积大,各单体钢屋盖平面投影尺寸为297m×350m,为大跨、大悬挑、超长的结构形式。介绍了主展厅钢屋盖的结构方案演变过程以及钢屋盖的抗风设计和为降低温度变化影响所采取的技术手段。主展厅钢屋盖是在综合考虑建筑功能需要、外观效果及结构安全可靠和结构经济性等因素的前提下,经过多方案比选,确定采用空间桁架结构体系。通过在屋盖悬挑部位设置抗风拉杆,有效降低风吸作用下桁架悬臂端的变形以及桁架杆件的内力。采用橡胶支座可有效解决由于温度变化在超长钢结构中产生的过大温度应力的问题。主展厅钢屋盖结构选型合理,可实现结构的安全可靠并具有较好的经济性。

Image itself information is naturally robust to image reconstruction, yet most current super-resolution methods do not fully utilize global feature information. This study proposes a new image super-resolution model mixing multiple and multi-scale attentions, including two new modules: Multi-scale hybrid non-local attention upsampling module and residual dense attention block. Different from previous nonlocal methods, multi-scale hybrid non-local attention upsampling module mixes pixel-based and patch-based nonlocal attention and establishes patch-level upsampling mapping relationships at multiple scales, which enables a wider global search space. The residual dense attention block establishes attention associations in channel and spatial dimensions, which enhances the transfer and fusion of front-to-back attention information through dense connections. In this study, quantitative and qualitative evaluations are conducted on several benchmark datasets, and the experimental results show that the model outperforms similar super-resolution models in terms of performance and reconstruction quality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Feed Industry is the property of Liaoning Provincial Institute of Agricultural Mechanization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To investigate the effect of daphnetin (DAPH) on pyroptosis of chondrocytes in osteoarthritis (OA) rats by regulating the MCP-1/CCR2 signaling axis. Methods A rat model of osteoarthritis was established by removing the anterior cruciate ligament and medial meniscus, and was randomly separated into an OA group, a low-dose DAPH (DAPH-L, 30 mg/kg) group, a high-dose DAPH (DAPH-H, 90 mg/k) group, a DAPH-H+CCL2 (5 ng CCL2) group, and a celecoxib (20 mg/kg) group. Ten rats with only open joint cavities were used as the sham surgery group, imaging was applied to analyze bone density (BMD), trabecular bone number (Tb-N), and bone volume fraction (BV/TV); ELISA was applied to detect the levels of interleukin-1β (IL-1β) and IL-18 in the serum of each group; HE and safranin were applied to detect morphological changes in cartilage tissue; qRT-PCR was applied to detect gene expression related to cartilage tissue necrosis (ASC, NLRP3, Caspase-1); Western blot was applied to detect the expression of MCP-1 and CCR2 proteins in cartilage tissue. Results Compared with the sham surgery group, the BMD, Tb-N, BV/TV in the OA group were decreased, the levels of IL-13 and IL-18 in serum, and the expression of ASC, NLRP3, Caspase-1 mRNA, MCP-1, and CCR2 proteins in cartilage tissue were increased (P<0.05); compared with the OA group, the BMD, Tb-N, BV/TV in the DAPH-L group, DAPH-H group, and celecoxib group were increased, the levels of IL-1ẞ and IL-18 in serum, and the expression of ASC, NLRP3, Caspase-1 mRNA, MCP-1, and CCR2 proteins in cartilage tissue were reduced, and there was a statistically obvious difference between the DAPH-L group with the DAPH- H group and the celecoxib group, respectively (P<0.05), but there was no statistically obvious difference between the DAPH-H group and the celecoxib group (P>0.05); compared with the DAPH-H group, the BMD, Tb-N, BV/TV in the DAPH-H+CCL2 group were decreased, the levels of IL-1β and IL-18 in serum, and the expression of ASC, NLRP3, Caspase-1 mRNA, MCP-1, and CCR2 proteins in cartilage tissue were increased (P<0.05). Conclusion DAPH reduces pyroptosis of chondrocytes in OA rats by regulating the MCP-1/CCR2 signaling axis. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Feed Industry is the property of Liaoning Provincial Institute of Agricultural Mechanization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Edulis Fungi is the property of Acta Edulis Fungi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the blind separation performance of approximate joint diagonalization of real matrix sets and to avoid trivial solutions, a Jacobi‑like joint diagonalization algorithm based on QR decomposition is proposed. Using the numerical stability of QR decomposition, the Jacobi rotation matrix is used to decompose the separation matrix into the product of several elementary triangular matrices and orthogonal matrices. The structure of Jacobi rotation matrix and the related elements of the target matrix transformation are used to obtain the optimal parameters. The high-dimensional minimization problem is iteratively transformed into a series of low-dimensional sub-problems, which enhances the recovery accuracy of the source signal. The algorithm complexity is reduced by solving the simplified Frobenius-norm objective function. The simulation results of mixed electrocardiogram (ECG) signals show that compared with QRJ2D, LUCJD and EGJLUD, the proposed algorithm has certain advantages in separation accuracy and convergence speed. [ABSTRACT FROM AUTHOR]

Copyright of Iron Steel Vanadium Titanium is the property of Iron Steel Vanadium Titanium Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The specificity, programmability and biocompatibility of DNA materials make them advantageous for applications in bio-detection and drug delivery. To further expand the applications and synthesis methods of DNA materials, in this study, Zn2+/DNA self-assembled nanoparticles (ZDNPs) with tumor-responsive marker microRNA-21 (miR-21) are simply and efficiently synthesized by utilizing the cooperative interaction between DNA and metal ions. Through the specific complementarity of the DNA hairpin structure in ZDNPs with miR-21, the fluorescent signal is activated and Zn2+ is released, which result in intracellular ROS production and can be used for fluorescence imaging and oxidative stress therapy of tumor. The synthesized ZDNPs are uniformly shaped spherical particles that can effectively load Zn2+. Depending on the responsive experiment of ZDNPs to miR-21, it is verified that there is a good linear fluorescence response signal with specificity between ZDNPs and miR-21 concentration. The linear response range is 5~160 nmol/L, and the detection limit is 5 nmol/L. The intracellular effects of ZDNPs are also investigated, and the results show that they can perform responsive fluorescence imaging, and mediate apoptosis of tumor cells through the oxidative stress pathway. As for in vivo fluorescence imaging and tumor therapy, ZDNPs demonstrate specific and sustained tracing ability at tumor lesion sites and produce significant growth inhibition effects on tumor. [ABSTRACT FROM AUTHOR]

Knowledge distillation combined with pre-trained language models is one of the primary methods for constructing question-answering models. However, these methods suffer from inefficiencies in knowledge transfer, time-consuming teacher model training, and mismatched capabilities between teacher and student models. To address these issues, this paper proposed a question-answering model based on self-distillation and self-ensemble, named SD-SE-BERT. The self-ensemble mechanism was designed based on a sliding window; the student model used BERT; the teacher model was derived from a weighted average combination of several student models during the training process, based on their performance on the validation set. The loss function used the output of the ensemble and the true labels to guide the training of the student model in the current round. Experimental results on the SQuAD1.1 dataset show that the EM and F1 scores of SD-SE-BERT are respectively 7.5 and 4.9 higher than those of the BERT model, and the model's performance surpasses other representative single models and distillation models. Compared to the fine-tuning results of the large-scale language model ChatGLM-6B, the EM score was improved by 4.5, and the F1 score by 2.5. It proves that SD-SE-BERT can leverage the model's supervision information to enhance the model's capacity to combine different text data features, eliminating the need for complex teacher-model training and avoiding the problem of mismatch between teacher and student models. [ABSTRACT FROM AUTHOR]

In recent years, deep reinforcement learning has been used as a model-free resource allocation method to solve the problem of co-channel interference in wireless networks. However, networks based on conventional experience replay strategies are difficult to learn valuable experiences, resulting in slower convergence speed; The manual method of determining the exploration step size does not take into account the learning situation of the algorithm in each training cycle, resulting in blind exploration of the environment and limited improvement of the system spectral efficiency. A distributed reinforcement learning power control method for frequency division multiple access systems is proposed, which adopts a priority experience replay strategy to encourage agents to learn more important data from the environment to accelerate the learning process. Moreover, an exploration strategy with dynamic adjustment of step size suitable for distributed reinforcement learning is designed. The strategy allows agents to explore the local environment based on their own learning situation and hence reduces the blindness caused by manually setting step sizes. The experimental results show that compared to existing algorithms, the proposed method accelerates the convergence speed, improves the ability of co-channel interference suppression in mobile scenarios, and gains higher performance in large networks. [ABSTRACT FROM AUTHOR]

For the beamforming design of intelligent reflector assisted large-scale MISO systems, most of the current researches are basing on the fully known channel state information, and do not consider the coupling relationship between the active beamforming matrix at the base station and the reflection coefficient matrix of intelligent reflector. The intelligent reflector assisted channel is a cascade channel, which is difficult to estimate and has high pilot frequency overhead. In view of this, this paper proposed a hybrid intelligent reflective surface architecture containing active and passive components. Firstly, based on the sparse characteristics of millimeter-wave channels, it used the compressed sensing algorithm to estimate the channels, and designed a two-stage convolutional network framework integrating attention mechanism to jointly optimize the reflection coefficient matrix and beamforming matrix with the aim of maximizing and rate. The experimental results show that compared to existing methods, the proposed method can achieve better sum rate performance with fewer pilots, effectively reducing pilot loss and reducing computational time complexity. And when the communication environment changes, the network also has good robustness. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Feed Research is the property of Editorial Board of Feed Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the implementation of pesticide reduction, plant-derived pesticides have received more and more attention because of their low toxicity and low residue. Limonene is a natural monocyclic terpene widely present in citrus essential oils, which has diverse biological activities, and has potential and application prospect in agricultural disease, pest and weed control. The research progress of limonene and its essential oil in the agricultural fields of insecticidal, acaricidal, phytocidal and antifungal activity in recent years, and the mechanism of its biological activities were briefly reviewed and summarized in this paper. Meanwhile, the registration of limonene formulations in China and the research progress and application of limonene nano-formulations against agricultural diseases and pests were introduced, and the future development trend and research direction of this field were prospected, which will provide the scientific basis for the application of limonene in pesticide reduction and agricultural disease, pest and weed control. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Technology Economics is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Resources & Environment / Nongye Ziyuan yu Huanjing Xuebao is the property of Journal of Agricultural Resources & Environment Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To establish a new model of indocyanine green (ICG) clearance test combined with total bilirubin actual resident rate (TBARR) for predicting the short-term prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) treated with artificial liver support system (ALSS) therapy. Methods A retrospective analysis was performed for the clinical data of 136 patients with HBV-ACLF who underwent ALSS therapy in Department of Infectious Diseases, The Affiliated Hospital of Southwest Medical University, from June 2017 to July 2021, and according to the prognosis at 3-month follow-up, they were divided into survival group with 92 patients and death group with 44 patients. Related indicators were measured at the time of the confirmed diagnosis of ACLF, including biochemical parameters, coagulation, indocyanine green retention rate at 15 minutes (ICGR15), and effective hepatic blood flow (EHBF), and related indices were calculated, including Model for End-Stage Liver Disease (MELD) score, MELD difference (ΔMELD), Child-Turcotte-Pugh (CTP) score, total bilirubin clearance rate (TBCR), total bilirubin rebound rate (TBRR), and TBARR. The Mann-Whitney U test was used for comparison of continuous data with skewed distribution between two groups; the chi-square test was used for comparison of categorical data between groups. A binary logistic regression analysis was used to establish a combined predictive model for the prognosis of HBV-ACLF after ALSS therapy. The area under the ROC curve (AUC) was used to compare the accuracy of various models in judging the short-term prognosis of patients with HBV-ACLF after ALSS therapy, and the Z test was used for comparison of AUC. Results There were significant differences between the death group and the survival group in MELD score, ΔMELD, CTP score, ICGR15, EHBF, TBRR, TBARR, neutrophil count, percentage of neutrophils, lymphocyte count, platelet count, alkaline phosphatase, gamma-glutamyl transpeptidase, total bilirubin, albumin, prothrombin time, international normalized ratio, prothrombin time activity, prealbumin, fibrinogen, serum sodium, age, and the incidence rate of hepatic encephalopathy (all P < 0.05). The multivariate logistic regression analysis showed that age (odds ratio [OR]=1.096, 95% confidence interval [CI]: 1.056-1.137, P < 0.001), neutrophil count (OR=1.214, 95%CI: 1.044-1.411, P=0.012), TBRR (OR=0.989, 95%CI: 0.982-0.996, P=0.001), TBARR (OR=1.073, 95%CI: 1.049-1.098, P < 0.001), ΔMELD (OR=1.480, 95%CI: 1.288-1.701, P < 0.001), CTP score (OR=2.081, 95%CI: 1.585-2.732, P < 0.001), and ICGR15(OR=1.116, 95%CI: 1.067-1.168, P < 0.001) were independent influencing factors for short-term mortality in patients with HBV-ACLF after ALSS therapy. The binary logistic regression analysis was used to establish four combined predictive models for predicting the prognosis of HBV-ACLF after ALSS therapy, i.e., TBRR-ICGR15, TBARR-ICGR15, TBARR-ICGR15-ΔMELD, and TBARR-ICGR15-ΔMELD-age, with an AUC of 0.830, 0.867, 0.900, and 0.917, respectively, and the combined predictive models had a larger AUC than each index alone (age, neutrophil count, TBRR, TBARR, ΔMELD, MELD score, CTP score, and ICGR15), among which the TBARR-ICGR15-ΔMELD-age model had the largest AUC. The combined models TBARR-ICGR15-ΔMELD and TBARR-ICGR15-ΔMELD-age had sensitivities and specificities of > 80%. Conclusion The combined predictive model established by ICGR15 and TBARR has a good value for in predicting the short-term prognosis of patients with HBV-ACLF after ALSS therapy, and the combined predictive model has a better accuracy than the single model in judging prognosis. [ABSTRACT FROM AUTHOR]

Off-label drug use (OLDU) is extremely common worldwide. However, if the safety of OLDU cannot be supported by sufficient evidence-based medicine, it will lead to legal disputes when it causes adverse events. OLDU should be considered with cautions especially for vulnerable populations, such as the elderly, children and pregnant women. In this article, according to off-lab contents and up-to-date guidelines, clinical trials and other evidence-based medicine at home and abroad, OLDU medication guidelines of immunotherapy drugs and COVID-19 antiviral drugs for COVID-19 therapy were collected and compiled. OLDU guidelines were formulated especially for the vulnerable populations, aiming to provide reference for clinical drug requirement and promote rational drug use. [ABSTRACT FROM AUTHOR]

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Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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