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Heavy oil represents a vital petroleum resource worldwide. As one of the major producers, China is facing great challenges in effective and economic production of heavy oil due to reservoir complexity. Plenty of efforts have been made to promote innovative advances in thermal recovery modes, methods, and processes for heavy oil in the country. The thermal recovery mode has been shifted from simple steam injection to a more comprehensive “thermal+'' strategy, such as a novel N2-steam hybrid process and CO2-enhanced thermal recovery techniques. These advanced techniques break through the challenges of heavy oil extraction from less accessible reservoirs with thinner oil layers and greater burial depths. Regarding thermal recovery methods, China has developed the steam-assisted gravity drainage method integrating flooding and drainage (also referred to as the hybrid flooding-drainage SAGD technology) for highly heterogeneous ultra-heavy oil reservoirs and the fire flooding method for nearly depleted heavy oil reservoirs, substantially improving oil recovery. Furthermore, a range of processes have been developed for heavy oil production, including the open hole completion process using sand control screens for horizontal wells, the process of integrated injection-recovery with horizontal pump for horizontal wells, the steam dryness maintenance, measurement, and control process, efficient and environment-friendly circulating fluidized bed (CFB) boilers with high steam dryness, the recycling process of produced water, and the thermal recovery process for offshore heavy oil. Based on the advances in methodology, technology, and philosophy, a series of supporting technologies for heavy oil production have been developed, leading to the breakthrough of existing technical limit of heavy oil recovery and the expansion into new exploitation targets. For the future heavy oil production in China, it is necessary to embrace a green, low-carbon, and energy-efficient development strategy, and to expand heavy oil extraction in reservoirs with larger burial depth, more viscous oil, thinner oil layers, and lower permeability. Moreover, it is highly recommended to collaboratively maximize oil recovery and oil-to-steam ratio through technological innovations, and boost intelligentization of heavy oil production.

The transformation of scientific and technological achievements is the best form of the combination of technology and the economy, and only when new technologies are transformed into commodities can they be transformed into real productive forces and exert scale effects. With the rapid development of digital finance, it has changed the operating mode of financial markets and consumer behavior. Does digital finance promote the transformation of R&D achievements? We empirically examine this question using the panel data covering 30 provinces in China from 2011 to 2021. The empirical results indicate that the development of digital finance can improve the transformation rate of R&D achievements. Additionally, we find that the role of digital finance in promoting the transformation of R&D achievements needs to be guaranteed by the level of effective financial regulation. The research conclusions are a relevant reference for the government to improve the transformation rate of scientific and technological achievements.

6-Gingerol (6G) is the main phenolic active component of ginger, which has a certain protective effect against liver injury induced by drugs, and chemical pollutants. However, the mechanism of protection of 6G against arsenic trioxide (ATO)-induced liver injury remains unclear. The network pharmacology and animal experiment results respectively indicated that oxidative stress and inflammatory responses were closely related to ATO-induced liver injury. 6G can alleviate ATO-induced liver injury and oxidative stress. Furthermore, 6G can attenuate the release of pro-inflammatory factors induced by ATO and reduce the expressions of NLRP3, ASC, Caspase-1 and gasdermin-D. The results showed that the activation of NLRP3 inflammatory and its induced pyroptosis play critical roles in liver injury caused by ATO. Furthermore, 6G can suppress the ROS-NLRP3 inflammasome signaling pathway, which may be an effective strategy for the treatment of ATO-induced liver injury.

Educational content recommendation is a cornerstone of AI-enhanced learning. In particular, to facilitate navigating the diverse learning resources available on learning platforms, methods are needed for automatically linking learning materials, e.g., in order to recommend textbook content based on exercises. Such methods are typically based on semantic textual similarity (STS) and the use of embeddings for text representation. However, it remains unclear what types of embeddings should be used for this task. In this study, we carry out an extensive empirical evaluation of embeddings derived from three different types of models: (i) static embeddings trained using a concept-based knowledge graph, (ii) contextual embeddings from a pre-trained language model, and (iii) contextual embeddings from a large language model (LLM). In addition to evaluating the models individually, various ensembles are explored based on different strategies for combining two models in an early vs. late fusion fashion. The evaluation is carried out using digital textbooks in Swedish for three different subjects and two types of exercises. The results show that using contextual embeddings from an LLM leads to superior performance compared to the other models, and that there is no significant improvement when combining these with static embeddings trained using a knowledge graph. When using embeddings derived from a smaller language model, however, it helps to combine them with knowledge graph embeddings. The performance of the best-performing model is high for both types of exercises, resulting in a mean Recall@3 of 0.96 and 0.95 and a mean MRR of 0.87 and 0.86 for quizzes and study questions, respectively, demonstrating the feasibility of using STS based on text embeddings for educational content recommendation. The ability to link digital learning materials in an unsupervised manner—relying only on readily available pre-trained models—facilitates the development of AI-enhanced learning.

Abstract Intervertebral disc (IVD) degeneration (IVDD) is the main cause of low back pain with major social and economic burdens; however, its underlying molecular mechanisms remain poorly defined. Here we show that the focal adhesion protein Kindlin-2 is highly expressed in the nucleus pulposus (NP), but not in the anulus fibrosus and the cartilaginous endplates, in the IVD tissues. Expression of Kindlin-2 is drastically decreased in NP cells in aged mice and severe IVDD patients. Inducible deletion of Kindlin-2 in NP cells in adult mice causes spontaneous and striking IVDD-like phenotypes in lumbar IVDs and largely accelerates progression of coccygeal IVDD in the presence of abnormal mechanical stress. Kindlin-2 loss activates Nlrp3 inflammasome and stimulates expression of IL-1β in NP cells, which in turn downregulates Kindlin-2. This vicious cycle promotes extracellular matrix (ECM) catabolism and NP cell apoptosis. Furthermore, abnormal mechanical stress reduces expression of Kindlin-2, which exacerbates Nlrp3 inflammasome activation, cell apoptosis, and ECM catabolism in NP cells caused by Kindlin-2 deficiency. In vivo blocking Nlrp3 inflammasome activation prevents IVDD progression induced by Kindlin-2 loss and abnormal mechanical stress. Of translational significance, adeno-associated virus-mediated overexpression of Kindlin-2 inhibits ECM catabolism and cell apoptosis in primary human NP cells in vitro and alleviates coccygeal IVDD progression caused by mechanical stress in rat. Collectively, we establish critical roles of Kindlin-2 in inhibiting Nlrp3 inflammasome activation and maintaining integrity of the IVD homeostasis and define a novel target for the prevention and treatment of IVDD.

Cardiotoxicity is a serious side effect of arsenic trioxide (ATO) which hinders its clinical use in cancer chemotherapy. Danshensu (DSS) has potential applications in the food and healthcare industry to promote cardiovascular health. The experiment aims to investigate the effects of DSS against ATO-induced cardiotoxicity and its possible mechanism. Our results demonstrated that DSS improved cardiac dysfunction, alleviated histopathological damage, enhanced antioxidant activity, attenuated cardiomyocyte apoptosis and suppressed inflammation. Further studies showed that DSS prevented ATO-caused activation of NF-κB by inhibiting the phosphorylation of AKT and IKK, degradation of IκBα, and nuclear translocation of NF-κB. In H9c2 cardiomyocytes, DSS significantly increased cell survival rate and inhibited ATO-mediated expression of p-AKT, p-IKKα/β, p-IκBα, and NF-κB. Notably, the efficacy of DSS was synergistically increased by AKT inhibitor GSK690693. To sum up, DSS effectively ameliorated ATO-induced cardiac toxicity in vivo and in vitro, which may be achieved through inhibition of the AKT/IKK/NF-κB pathway.

Shock-induced plastic deformation and spall damage in the single-crystalline FCC Co25Ni25Fe25Al7.5Cu17.5 high-entropy alloy (HEA) under varying shock intensities were systematically investigated using large-scale molecular dynamics simulations. The study reveals the significant influence of crystalline orientation on the deformation mechanism and spall damage. Specifically, the shock wave velocities in the [110] and [111] directions are significantly higher than that in the [001] direction, resulting in a two-zone elastic-plastic shock wave structure observed in the [110] and [111] samples, while only a single-wave structure is found in the [001] sample. The plastic deformation is dominated by the FCC to BCC transformation following the Bain path and a small amount of stacking faults during the compression stage in the [001] sample, whereas it depends on the stacking faults induced by Shockley dislocation motion in the [110] and [111] samples. The stacking faults and phase transformation in the [001] sample exhibit high reversibility under release effects, while extensive dislocations are present in the [110] and [111] samples after release. Interestingly, tension-strain-induced FCC to BCC phase transformation is observed in the [001] sample during the release stage, resulting in increased spall strength compared to the [110] and [111] samples. The spall strength estimated from both bulk and free surface velocity history shows reasonable consistency. Additionally, the spall strength remains stable with increasing shock intensities. The study discusses in detail the shock wave propagation, microstructure change, and spall damage evolution. Overall, our comprehensive studies provide deep insights into the deformation and fracture mechanisms of Co25Ni25Fe25Al7.5Cu17.5 HEA under shock loading, contributing to a better understanding of dynamic deformation under extreme environments.

Liquiritigenin (LQ) has protective effects against various hepatotoxicities. However, its specific role on arsenic trioxide (ATO)-induced hepatotoxicity and the related biomolecular mechanisms remain unclear. The purpose of this study is to explore the protective actions of LQ on ATO-induced hepatotoxicity and its biomolecular mechanisms in mice. LQ was administered orally at 20 and 40 mg/kg per day for seven consecutive days with an intraperitoneal injection of ATO (5 mg/kg). Liver injury was induced by ATO and was alleviated by treatment with LQ as reflected by reduced histopathological damage of liver and decreased serum ALT, AST, and ALP levels. The generation of intracellular ROS induced by ATO was attenuated after LQ treatment. The levels of SOD, CAT, and GSH were elevated with LQ administration while MDA levels decreased. LQ mitigated elevated TNF-α and IL-6 levels as well as the hepatic mitochondrial damage caused by ATO. Moreover, LQ upregulated the expression of LC3-II and enhanced autophagy in the liver of ATO-induced mice. Further studies indicated that LQ significantly suppressed the expression of p-PI3K, p-AKT, and p-mTOR in ATO-induced mice. In conclusion, our findings show that LQ protects against ATO-induced hepatotoxicity due to its antioxidant and anti-inflammatory activities and enhancement of autophagy mediated by the PI3K/AKT/mTOR signaling pathway in mice.

Formative feedback has long been recognised as an effective tool for student learning, and researchers have investigated the subject for decades. However, the actual implementation of formative feedback practices is associated with significant challenges because it is highly time-consuming for teachers to analyse students’ behaviours and to formulate and deliver effective feedback and action recommendations to support students’ regulation of learning. This paper proposes a novel approach that employs learning analytics techniques combined with explainable machine learning to provide automatic and intelligent feedback and action recommendations that support student’s self-regulation in a data-driven manner, aiming to improve their performance in courses. Prior studies within the field of learning analytics have predicted students’ performance and have used the prediction status as feedback without explaining the reasons behind the prediction. Our proposed method, which has been developed based on LMS data from a university course, extends this approach by explaining the root causes of the predictions and by automatically providing data-driven intelligent recommendations for action. Based on the proposed explainable machine learning-based approach, a dashboard that provides data-driven feedback and intelligent course action recommendations to students is developed, tested and evaluated. Based on such an evaluation, we identify and discuss the utility and limitations of the developed dashboard. According to the findings of the conducted evaluation, the dashboard improved students’ learning outcomes, assisted them in self-regulation and had a positive effect on their motivation.

Nucleus pulposus-derived stem/progenitor cells (NPSCs) provide novel prospects for the regeneration of degenerated intervertebral disc (IVD). Nevertheless, with aging and degeneration of IVD, the frequency of NPSCs markedly decreases. Excessive cell death could be the main reason for declined frequency of NPSCs, however, the exact mechanisms remain elusive. Thus, the present study was undertaken to explore the mechanisms of compression-induced NPSCs death, and the effects of heat shock protein 90 (HSP90) on NPSCs survival. Here, we found that compression could trigger receptor-interacting protein kinase 1 (RIPK1)/receptor-interacting protein kinase 3 (RIPK3)/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis of NPSCs. Furthermore, we found that elevated expression of HSP90 was involved in compression-induced NPSCs death, and inhibiting HSP90 could dramatically attenuate compression-induced necroptosis of NPSCs via regulating the expression and activity of RIPK1/RIPK3/MLKL, and alleviating the mitochondrial dysfunction (mitochondrial membrane potential loss and ATP depletion) and oxidative stress [production of mitochondrial reactive oxygen species (ROS), cellular total ROS and malondialdehyde, and downregulation of superoxide dismutase 2]. Besides necroptosis, compression-induced apoptosis of NPSCs was also attenuated by HSP90 inhibition. In addition, we found that enhanced expression of HSP70 contributed to the cytoprotective effects of inhibiting HSP90. More encouragingly, our results demonstrated that inhibiting HSP90 could also mitigate the exhaustion of NPSCs in vivo. In conclusion, RIPK1/RIPK3/MLKL-mediated necroptosis participates in compression-induced NPSCs death. Furthermore, targeting HSP90 to simultaneously inhibit necroptosis and apoptosis of NPSCs might be an efficient strategy for preventing the death of NPSCs, thus rescuing the endogenous repair capacity of NP tissue.

Taxol has been clinically approved as an antitumor drug, and it exerts its antitumor effect through the excessive stabilization of microtubules in cancer cells. Recently, moderate microtubule stabilization by Taxol has been shown to efficiently promote neurite regeneration and functional recovery after spinal cord injury (SCI). However, the potential for the clinical translation of Taxol in treating SCI is limited by its side effects and low ability to cross the blood-spinal cord barrier (BSCB). Self-assembled peptide hydrogels have shown potential as drug carriers for the local delivery of therapeutic agents. We therefore hypothesized that the localized delivery of Taxol by a self-assembled peptide scaffold would promote axonal regeneration by stabilizing microtubules during the treatment of SCI. In the present study, the mechanistic functions of the Taxol-releasing system were clarified in vitro and in vivo using immunofluorescence labeling, histology and neurobehavioral analyses. Based on the findings from the in vitro study, Taxol released from a biological functionalized SAP nanofiber scaffold (FGLmx/Taxol) remained active and promoted neurite extension. In this study, we used a weight-drop contusion model to induce SCI at T9. The local delivery of Taxol from FGLmx/Taxol significantly decreased glial scarring and increased the number of nerve fibers compared with the use of FGLmx and 5% glucose. Furthermore, animals administered FGLmx/Taxol exhibited neurite preservation, smaller cavity dimensions, and decreased inflammation and demyelination. Thus, the local delivery of Taxol from FGLmx/Taxol was effective at promoting recovery after SCI and has potential as a new therapeutic strategy for SCI.

Background: Coronavirus disease 2019 (COVID-19) broke out in Wuhan, the People's Republic of China, in December 2019 and now is a pandemic all around the world. Some orthopaedic surgeons in Wuhan were infected with COVID-19.Methods: We conducted a survey to identify the orthopaedic surgeons who were infected with COVID-19 in Wuhan. A self-administered questionnaire was distributed to collect information such as social demographic variables, clinical manifestations, exposure history, awareness of the outbreak, infection control training provided by hospitals, and individual protection practices. To further explore the possible risk factors at the individual level, a 1:2 matched case-control study was conducted.Results: A total of 26 orthopaedic surgeons from 8 hospitals in Wuhan were identified as having COVID-19. The incidence in each hospital varied from 1.5% to 20.7%. The onset of symptoms was from January 13 to February 5, 2020, and peaked on January 23, 8 days prior to the peak of the public epidemic. The suspected sites of exposure were general wards (79.2%), public places at the hospital (20.8%), operating rooms (12.5%), the intensive care unit (4.2%), and the outpatient clinic (4.2%). There was transmission from these doctors to others in 25% of cases, including to family members (20.8%), to colleagues (4.2%), to patients (4.2%), and to friends (4.2%). Participation in real-time training on prevention measures was found to have a protective effect against COVID-19 (odds ratio [OR], 0.12). Not wearing an N95 respirator was found to be a risk factor (OR, 5.20 [95% confidence interval (CI), 1.09 to 25.00]). Wearing respirators or masks all of the time was found to be protective (OR, 0.15). Severe fatigue was found to be a risk factor (OR, 4 [95% CI, 1 to 16]) for infection with COVID-19.Conclusions: Orthopaedic surgeons are at risk during the COVID-19 pandemic. Common places of work could be contaminated. Orthopaedic surgeons have to be more vigilant and take more precautions to avoid infection with COVID-19.Level Of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

AbstractRiluzole, a sodium/glutamate antagonist has shown promise as a neuroprotective agent. It is licensed for amyotrophic lateral sclerosis and is in clinical trial development for spinal cord injury (SCI). This study investigated the therapeutic time-window and pharmacokinetics of riluzole in a rodent model of cervical SCI. Rats were treated with riluzole (8 mg/kg) at 1 hour (P1) and 3 hours (P3) after injury or with vehicle. Afterward, P1 and P3 groups received riluzole (6 (mg/kg) every 12 hours for 7 days. Both P1 and P3 animals had significant improvements in locomotor recovery as measured by open field locomotion (BBB score, BBB subscore). Von Frey stimuli did not reveal an increase in at level or below level mechanical allodynia. Sensory-evoked potential recordings and quantification of axonal cytoskeleton demonstrated a riluzole-mediated improvement in axonal integrity and function. Histopathological and retrograde tracing studies demonstrated that delayed administration leads to tissue preservation and reduces apoptosis and inflammation. High performance liquid chromatography (HPLC) was undertaken to examine the pharmacokinetics of riluzole. Riluzole penetrates the spinal cord in 15 min, and SCI slowed elimination of riluzole from the spinal cord, resulting in a longer half-life and higher drug concentration in spinal cord and plasma. Initiation of riluzole treatment 1 and 3 hours post-SCI led to functional, histological, and molecular benefits. While extrapolation of post-injury time windows from rat to man is challenging, evidence from SCI-related biomarker studies would suggest that the post-injury time window is likely to be at least 12 hours in man. [ABSTRACT FROM AUTHOR]

The expression of Smad2 and Smad3 and the influence of exogenous transforming growth factorβ1 (TGFβ1) on them in rat bone marrow-derived mesenchymal stem cells (MSCs) cultured in vitro were investigated. The effects of different concentrations of TGFβ1 on cell proliferation and ALP activity were detected by MTT and PNPP in, MSCs respectively. The expression of Smad2 and Smad3 and the influence of exogenous TGFβ1 on them were also examined by immunocytochemistry and Western blot assays. The exogenous TGFβ1 induced a dose-dependent decrease in cell proliferation and a dose-dependent increase, in ALP activity, which plateaued at 5 ng/ml. Smad2 and Smad3 proteins were detected only in the cytoplasm in the absence of TGFβ1 and TGFβ1 could stimulate the translocation of them from the cytoplasm to the nucleus. The total amount of Smad2 protein remained unchanged before and after TGFβ1 treatment ( P>0.05). The expression levels of Smad3 remained unchanged after 3 h and 6 h treatment ( P>0.05), but decreased markedly after 24 h treatment ( P<0.05). It was concluded that TGFβ1 is a latent osteoinductive factor involved in osteoblastic differentiation. Both Samd2 and Samd3 mediate TGFβ1 signaling as downstream mediators in MSCs. The biological output of TGFβ1 triggering the osteoblastic differentiation could be entirely determined by Smad3 in MSCs. [ABSTRACT FROM AUTHOR]