Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify th...Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify the integrity of query results returned.Since existing verifiable queries based on an authenticated data structure(ADS)suffer from significant network,storage and computing overheads by virtue of verification objects(VOs),an alternative way turns to the trusted execution environment(TEE),with which light clients do not need to receive or verify any VO.However,state-of-the-art TEEs cannot deal with large-scale applications conveniently due to the limited secure memory space(e.g.,the size of the enclave in Intel SGX(software guard extensions),a typical TEE product,is only 128 MB).Hence,we organize data hierarchically in trusted(enclave)and untrusted memory,along with hot data buffered in the enclave to reduce page swapping overhead between two kinds of memory.The cost analysis and empirical study validate the effectiveness of our proposed scheme.The VO size of our scheme is reduced by one to two orders of magnitude compared with that of the traditional scheme.展开更多
Vacuum sealing drainage (VSD) is frequently used in abdominal surgeries. However, relevant guidelines are rare. Chin ese Trauma Surge on Associati on orga nized a committee composed of 28 experts across China in July ...Vacuum sealing drainage (VSD) is frequently used in abdominal surgeries. However, relevant guidelines are rare. Chin ese Trauma Surge on Associati on orga nized a committee composed of 28 experts across China in July 2017, aiming to provide an evidence-based recommendation for the application of VSD in abdominal surgeries.Eleven questions regarding the use of VSD in abdominal surgeries were addressed:(1) which type of materials should be respectively chosen for the intraperitoneal cavity, retroperitoneal cavity and superficial incisions?(2) Can VSD be preventively used for a high-risk abdominal incision w让h primary suture?(3) Can VSD be used in severely contaminated/infected abdominal surgical sites?(4) Can VSD be used for temporary abdominal cavity closure under some special conditions such as severe abdominal trauma, infection, liver transplantation and intra-abdominal volume increment in abdominal compartment syndrome?(5) Can VSD be used in abdominal organ inflammation, injury, or postoperative drainage?(6) Can VSD be used in the treatment of intestinal fistula and pancreatic fistula?(7) Can VSD be used in the treatment of intra-abdominal and extra-peritoneal abscess?(8) Can VSD be used in the treatment of abdominal wall wounds, wound cavity, and defects?(9) Does VSD in crease the risk of bleeding?(10) Does VSD increase the risk of intestinal wail injury?(11) Does VSD increase the risk of peritoneal adhesion? Focusing on these questions, evidence-based recommendations were given accordingly. VSD was strongly recommended regarding the questions 2-4. Weak recommendations were made regarding questions 1 and 5-11. Proper use of VSD in abdominal surgeries can lower the risk of infection in abdominal incisions with primary suture, treat severely contaminated/infected surgical sites and facilitate temporary abdominal cavity closure.展开更多
基金supported by the National Key Research and Development Program of China under Grant No.2021YFB-2700100the National Natural Science Foundation of China under Grant Nos.U1911203,U1811264 and 61972152.
文摘Due to limited computing and storage resources,light clients and full nodes coexist in a typical blockchain system.Any query from light clients must be forwarded to full nodes for execution,and light clients verify the integrity of query results returned.Since existing verifiable queries based on an authenticated data structure(ADS)suffer from significant network,storage and computing overheads by virtue of verification objects(VOs),an alternative way turns to the trusted execution environment(TEE),with which light clients do not need to receive or verify any VO.However,state-of-the-art TEEs cannot deal with large-scale applications conveniently due to the limited secure memory space(e.g.,the size of the enclave in Intel SGX(software guard extensions),a typical TEE product,is only 128 MB).Hence,we organize data hierarchically in trusted(enclave)and untrusted memory,along with hot data buffered in the enclave to reduce page swapping overhead between two kinds of memory.The cost analysis and empirical study validate the effectiveness of our proposed scheme.The VO size of our scheme is reduced by one to two orders of magnitude compared with that of the traditional scheme.
文摘Vacuum sealing drainage (VSD) is frequently used in abdominal surgeries. However, relevant guidelines are rare. Chin ese Trauma Surge on Associati on orga nized a committee composed of 28 experts across China in July 2017, aiming to provide an evidence-based recommendation for the application of VSD in abdominal surgeries.Eleven questions regarding the use of VSD in abdominal surgeries were addressed:(1) which type of materials should be respectively chosen for the intraperitoneal cavity, retroperitoneal cavity and superficial incisions?(2) Can VSD be preventively used for a high-risk abdominal incision w让h primary suture?(3) Can VSD be used in severely contaminated/infected abdominal surgical sites?(4) Can VSD be used for temporary abdominal cavity closure under some special conditions such as severe abdominal trauma, infection, liver transplantation and intra-abdominal volume increment in abdominal compartment syndrome?(5) Can VSD be used in abdominal organ inflammation, injury, or postoperative drainage?(6) Can VSD be used in the treatment of intestinal fistula and pancreatic fistula?(7) Can VSD be used in the treatment of intra-abdominal and extra-peritoneal abscess?(8) Can VSD be used in the treatment of abdominal wall wounds, wound cavity, and defects?(9) Does VSD in crease the risk of bleeding?(10) Does VSD increase the risk of intestinal wail injury?(11) Does VSD increase the risk of peritoneal adhesion? Focusing on these questions, evidence-based recommendations were given accordingly. VSD was strongly recommended regarding the questions 2-4. Weak recommendations were made regarding questions 1 and 5-11. Proper use of VSD in abdominal surgeries can lower the risk of infection in abdominal incisions with primary suture, treat severely contaminated/infected surgical sites and facilitate temporary abdominal cavity closure.
