This paper presents some numerical simulations using Discontinuous Deformation Analysis (DDA). First, DDA was applied to reproduce a series of granular flows released in a large flume. The comparison between simulated...This paper presents some numerical simulations using Discontinuous Deformation Analysis (DDA). First, DDA was applied to reproduce a series of granular flows released in a large flume. The comparison between simulated velocity and that measured in the tests demonstrates the effectiveness of DDA on description of kinematic behavior of blocky assembly. Simulated results were highly sensitive to the shape and angularity of blocky elements. Employing unrealistic block might result in different behavior from real situation. Second, three large landslides triggered by the Wenchuan earthquake were simulated. A well agreement with field data was obtained if apparent friction coefficient determined by post-analysis was adopted.展开更多
The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-member...The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-membered phosphorus heterocycles.The heterocyclizaional possibility of LR with bifunctional compounds was also discussed.展开更多
Radiotherapy is one of the main therapeutic methods for cancers;however,nonselective killing of normal cells and tumor cells by X-ray inevitably results in toxicity and side effects.Developing low-toxicity and high-ef...Radiotherapy is one of the main therapeutic methods for cancers;however,nonselective killing of normal cells and tumor cells by X-ray inevitably results in toxicity and side effects.Developing low-toxicity and high-efficiency radiosensitizers to reduce the practical dose of X-ray is a promising approach to overcoming these side effects.Here,we report the use of carboxylatecontaining organic ligands to construct one-dimensional high-Z lanthanide chains for efficient response to X-ray.The onedimensional lanthanide chains are stacked through weak interactions to form coordination nanoframeworks in the presence of polyethylenimine(PEI).The morphology and activity of the synthesized nanoframeworks can be regulated through selenium atom engineering.This study presents a promising approach for effective radiotherapy through selenium-engineering stable lanthanide nanoframeworks with precise coordination structures as radiosensitizers to mitigate X-ray side effects.展开更多
Radiotherapy is widely used clinically, but the toxic and side effects of nonselective killing of high-energy radiation limit its application. Finding biocompatible materials to assemble radiotherapy sensitizers and s...Radiotherapy is widely used clinically, but the toxic and side effects of nonselective killing of high-energy radiation limit its application. Finding biocompatible materials to assemble radiotherapy sensitizers and studying their sensitization patterns are of great significance for the clinical application. Here, biocompatible zinc porphyrin was chosen as sub-unit to construct various dimensional coordination frameworks. By employing top-down approach, suitable nanoframeworks with various dimensional zinc porphyrin were synthesized as radiosensitizers. The experimental data showed that high-dimensional zinc porphyrin nanoframeworks exhibit higher X-ray response performance.展开更多
Session-based recommendation aims to predict the next item based on a user’s limited interactions within a short period.Existing approaches use mainly recurrent neural networks(RNNs)or graph neural networks(GNNs)to m...Session-based recommendation aims to predict the next item based on a user’s limited interactions within a short period.Existing approaches use mainly recurrent neural networks(RNNs)or graph neural networks(GNNs)to model the sequential patterns or the transition relationships between items.However,such models either ignore the over-smoothing issue of GNNs,or directly use cross-entropy loss with a softmax layer for model optimization,which easily results in the over-fitting problem.To tackle the above issues,we propose a self-supervised graph learning with target-adaptive masking(SGL-TM)method.Specifically,we first construct a global graph based on all involved sessions and subsequently capture the self-supervised signals from the global connections between items,which helps supervise the model in generating accurate representations of items in the ongoing session.After that,we calculate the main supervised loss by comparing the ground truth with the predicted scores of items adjusted by our designed target-adaptive masking module.Finally,we combine the main supervised component with the auxiliary self-supervision module to obtain the final loss for optimizing the model parameters.Extensive experimental results from two benchmark datasets,Gowalla and Diginetica,indicate that SGL-TM can outperform state-of-the-art baselines in terms of Recall@20 and MRR@20,especially in short sessions.展开更多
The search of highly efficient drugs for overcoming cancer drug resistance continues to be a challenge for scientists.Constructing a metal drug based in situ oxidation-state transition system to disturb the redox bala...The search of highly efficient drugs for overcoming cancer drug resistance continues to be a challenge for scientists.Constructing a metal drug based in situ oxidation-state transition system to disturb the redox balance in cancer cells is a promising approach for overcoming cancer drug resistance.Inspired by natural redox-active copper enzyme centers,we developed a Cu(Ⅰ)-Cu(Ⅱ) in situ transition system in this work.Through atom engineering,we fine-tuned the thermodynamic stability of this system to investigate its anticancer activity.The results indicated that the synthetic Cu(Ⅰ)-Cu(Ⅱ) system could under-go in situ transition in vitro and in vivo,to disrupt the intracellular redox balance and trigger mitochondrial dysfunction and G2/M arrest,leading to apoptosis and overcoming cancer drug resistance.This study presents a feasible way to overcome cancer drug resistance by designing an in situ oxidation-state transition metal drug system.展开更多
Query suggestions help users refine their queries after they input an initial query.Previous work on query suggestion has mainly concentrated on approaches that are similarity-based or context-based,developing models ...Query suggestions help users refine their queries after they input an initial query.Previous work on query suggestion has mainly concentrated on approaches that are similarity-based or context-based,developing models that either focus on adapting to a specific user(personalization)or on diversifying query aspects in order to maximize the probability of the user being satisfied(diversification).We consider the task of generating query suggestions that are both personalized and diversified.We propose a personalized query suggestion diversification(PQSD)model,where a user's long-term search behavior is injected into a basic greedy query suggestion diversification model that considers a user's search context in their current session.Query aspects are identified through clicked documents based on the open directory project(ODP)with a latent dirichlet allocation(LDA)topic model.We quantify the improvement of our proposed PQSD model against a state-of-the-art baseline using the public america online(AOL)query log and show that it beats the baseline in terms of metrics used in query suggestion ranking and diversification.The experimental results show that PQSD achieves its best performance when only queries with clicked documents are taken as search context rather than all queries,especially when more query suggestions are returned in the list.展开更多
Introduction The family is the most basic unit of society and its development provides important support and impetus to social advances.China has the largest population in the world and the greatest number of families...Introduction The family is the most basic unit of society and its development provides important support and impetus to social advances.China has the largest population in the world and the greatest number of families,whose sizes,structures and types are becoming increasingly diverse and complex,keeping pace with ever-changing external circumstances.展开更多
文摘This paper presents some numerical simulations using Discontinuous Deformation Analysis (DDA). First, DDA was applied to reproduce a series of granular flows released in a large flume. The comparison between simulated velocity and that measured in the tests demonstrates the effectiveness of DDA on description of kinematic behavior of blocky assembly. Simulated results were highly sensitive to the shape and angularity of blocky elements. Employing unrealistic block might result in different behavior from real situation. Second, three large landslides triggered by the Wenchuan earthquake were simulated. A well agreement with field data was obtained if apparent friction coefficient determined by post-analysis was adopted.
文摘The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-membered phosphorus heterocycles.The heterocyclizaional possibility of LR with bifunctional compounds was also discussed.
基金supported by the National Natural Science Foundation of China(Nos.21877049,22177038,and 32171296)Guangdong Natural Science Foundation(Nos.2022A1515012235 and 2020B1515120043)+1 种基金Guangdong Pearl River Talent Program(No.2017GC010354)Innovation Team Project in Guangdong Colleges and Universities(Nos.2019KCXTD008 and 2019KTSCX012).
文摘Radiotherapy is one of the main therapeutic methods for cancers;however,nonselective killing of normal cells and tumor cells by X-ray inevitably results in toxicity and side effects.Developing low-toxicity and high-efficiency radiosensitizers to reduce the practical dose of X-ray is a promising approach to overcoming these side effects.Here,we report the use of carboxylatecontaining organic ligands to construct one-dimensional high-Z lanthanide chains for efficient response to X-ray.The onedimensional lanthanide chains are stacked through weak interactions to form coordination nanoframeworks in the presence of polyethylenimine(PEI).The morphology and activity of the synthesized nanoframeworks can be regulated through selenium atom engineering.This study presents a promising approach for effective radiotherapy through selenium-engineering stable lanthanide nanoframeworks with precise coordination structures as radiosensitizers to mitigate X-ray side effects.
基金supported by National Natural Science Foundation of China (Nos. 21877049, 22177038, 32171296)Guangdong Natural Science Foundation (Nos. 2020B1515120043, 2022A1515012235)+2 种基金Major Program for Tackling Key Problems of Industrial Technology in Guangzhou (Nos. 201902020013)Guangdong Pearl River Talent Program (No. 2017GC010354)Innovation Team Project in Guangdong Colleges and Universities (Nos. 2019KCXTD008, 2019KTSCX012)。
文摘Radiotherapy is widely used clinically, but the toxic and side effects of nonselective killing of high-energy radiation limit its application. Finding biocompatible materials to assemble radiotherapy sensitizers and studying their sensitization patterns are of great significance for the clinical application. Here, biocompatible zinc porphyrin was chosen as sub-unit to construct various dimensional coordination frameworks. By employing top-down approach, suitable nanoframeworks with various dimensional zinc porphyrin were synthesized as radiosensitizers. The experimental data showed that high-dimensional zinc porphyrin nanoframeworks exhibit higher X-ray response performance.
文摘Session-based recommendation aims to predict the next item based on a user’s limited interactions within a short period.Existing approaches use mainly recurrent neural networks(RNNs)or graph neural networks(GNNs)to model the sequential patterns or the transition relationships between items.However,such models either ignore the over-smoothing issue of GNNs,or directly use cross-entropy loss with a softmax layer for model optimization,which easily results in the over-fitting problem.To tackle the above issues,we propose a self-supervised graph learning with target-adaptive masking(SGL-TM)method.Specifically,we first construct a global graph based on all involved sessions and subsequently capture the self-supervised signals from the global connections between items,which helps supervise the model in generating accurate representations of items in the ongoing session.After that,we calculate the main supervised loss by comparing the ground truth with the predicted scores of items adjusted by our designed target-adaptive masking module.Finally,we combine the main supervised component with the auxiliary self-supervision module to obtain the final loss for optimizing the model parameters.Extensive experimental results from two benchmark datasets,Gowalla and Diginetica,indicate that SGL-TM can outperform state-of-the-art baselines in terms of Recall@20 and MRR@20,especially in short sessions.
基金supported by National Natural Science Foundation of China (21877049,22177038,32171296)Guangdong Natural Science Foundation (2020B1515120043,2022A1515012235)+2 种基金the Major Program for Tackling Key Problems of Industrial Technology in Guangzhou (201902020013)Guangdong Pearl River Talent Program(2017GC010354)the Innovation Team Project in Guangdong Colleges and Universities (2019KCXTD008,2019KTSCX012)
文摘The search of highly efficient drugs for overcoming cancer drug resistance continues to be a challenge for scientists.Constructing a metal drug based in situ oxidation-state transition system to disturb the redox balance in cancer cells is a promising approach for overcoming cancer drug resistance.Inspired by natural redox-active copper enzyme centers,we developed a Cu(Ⅰ)-Cu(Ⅱ) in situ transition system in this work.Through atom engineering,we fine-tuned the thermodynamic stability of this system to investigate its anticancer activity.The results indicated that the synthetic Cu(Ⅰ)-Cu(Ⅱ) system could under-go in situ transition in vitro and in vivo,to disrupt the intracellular redox balance and trigger mitochondrial dysfunction and G2/M arrest,leading to apoptosis and overcoming cancer drug resistance.This study presents a feasible way to overcome cancer drug resistance by designing an in situ oxidation-state transition metal drug system.
基金supported by the National Natural Science Foundation of China(Grant No.61702526)the National Advanced Research Project(6141B0801010b)。
文摘Query suggestions help users refine their queries after they input an initial query.Previous work on query suggestion has mainly concentrated on approaches that are similarity-based or context-based,developing models that either focus on adapting to a specific user(personalization)or on diversifying query aspects in order to maximize the probability of the user being satisfied(diversification).We consider the task of generating query suggestions that are both personalized and diversified.We propose a personalized query suggestion diversification(PQSD)model,where a user's long-term search behavior is injected into a basic greedy query suggestion diversification model that considers a user's search context in their current session.Query aspects are identified through clicked documents based on the open directory project(ODP)with a latent dirichlet allocation(LDA)topic model.We quantify the improvement of our proposed PQSD model against a state-of-the-art baseline using the public america online(AOL)query log and show that it beats the baseline in terms of metrics used in query suggestion ranking and diversification.The experimental results show that PQSD achieves its best performance when only queries with clicked documents are taken as search context rather than all queries,especially when more query suggestions are returned in the list.
文摘Introduction The family is the most basic unit of society and its development provides important support and impetus to social advances.China has the largest population in the world and the greatest number of families,whose sizes,structures and types are becoming increasingly diverse and complex,keeping pace with ever-changing external circumstances.