Background It is still controversial whether percutaneous coronary intervention with drug-eluting stent （DES） is safe and effective compared to coronary artery bypass graft surgery （CABG） for unprotected left main...Background It is still controversial whether percutaneous coronary intervention with drug-eluting stent （DES） is safe and effective compared to coronary artery bypass graft surgery （CABG） for unprotected left main coronary artery （ULMCA） disease at long-term follow up （≥3 years）. Methods Eligible studies were selected by searching PubMed, EMBASE, and Cochrane Library up to December 6, 2016. The primary endpoint was a composite of death, myocardial infarction （MI） or stroke during the longest follow-up. Death, cardiac death, MI, stroke and repeat revascularization were the secondary outcomes. Results Four randomized controlled trials and twelve adjusted observational studies involving 14,130 patients were included. DES was comparable to CABG regarding the occurrence of the primary endpoint （FIR = 0.94, 95% CI： 0.86-1.03）. Besides, DES was significantly associated with higher incidence of MI （HR = 1.56, 95% CI： 1.09-2.22） and repeat revascularization （HR = 3.09, 95% CI： 2.33-4.10） compared with CABG, while no difference was found between the two strategies regard as the rate of death, cardiac death and stroke. Furthermore, DES can reduce the risk of the composite endpoint of death, MI or stroke （HR = 0.80, 95% CI： 0.67-0.95） for ULMCA lesions with SYNTAX score ≤32. Conclusions Although with higher risk of repeat revascularization, PCI with DES appears to be as safe as CABG for ULMCA disease at long-term follow up. In addition, treatment with DES could be an alternative interventional strategy to CABG for ULMCA lesions with low to intermediate anatomic complexity.展开更多
This paper presents the method for the performance calibration of AACMM （articulated arm coordinate measuring machines） according to ASME B89.4.22 Standard. The growing use of this class of measurement equipment has...This paper presents the method for the performance calibration of AACMM （articulated arm coordinate measuring machines） according to ASME B89.4.22 Standard. The growing use of this class of measurement equipment has been accompanied by an absence of authorized laboratories to provide calibration certificates for its performance. Due to ASME B89.4.22 and VD12617-9 are nowadays the unique standards in the field of AACMM verification, IK4 Tekniker has compared both of them in order to develop internal test procedures to yield reliable performance calibration results. As a result, IK4 Tekniker has been recognized by the Spanish Accreditation Body （ENAC） in the field of AACMM calibration. Internal test procedures and uncertainty evaluation analysis have been developed as well as ENAC certificated reference test equipments have been acquired to ensure a suitable AACMM calibration process.展开更多
The framework of digital signature based on qualified certificates and X. 509 architecture is known to have many security risks. Moreover, the fraud prevention mechanism is fragile and does not provide strong guarante...The framework of digital signature based on qualified certificates and X. 509 architecture is known to have many security risks. Moreover, the fraud prevention mechanism is fragile and does not provide strong guarantees that can be necessary for flow of legal documents. Mediated signatures have been proposed as a mechanism to effectively disable signature cards. In this paper we propose further mechanisms that can be applied on top of mediated RSA, compatible with the standard format, but providing security guarantees even in the case when RSA becomes broken or the keys are compromised. The solution is immune tokleptographic attacks as only deterministic algorithms are used on user＇s side.展开更多
In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource ...In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource utilization, poor innovation ability, etc. And we point out the problems and challenges faced by traditional standards library in the network environment. The standards library must redesign the organization structure and business process radically so that standards library could improve the service model, enhance the service quality and utilization rate of various document resources.展开更多
Hybrid signcryption is an important technique signcrypting bulk data using symmetric encryption. In this paper, we apply the technique of certificateless hybrid signcryption to an elliptic-curve cryptosystem, and cons...Hybrid signcryption is an important technique signcrypting bulk data using symmetric encryption. In this paper, we apply the technique of certificateless hybrid signcryption to an elliptic-curve cryptosystem, and construct a low-computation certificateless hybrid signcryption scheme. In the random oracle model, this scheme is proven to have indistinguishability against adaptive chosen-ciphertext attacks （IND-CCA2） under the elliptic-curve computation Diffie-Hellman assumption. Also, it has a strong existential unforgeability against adaptive chosen-message attacks （sUF-CMA） under the elliptic-curve discrete logarithm assumption. Analysis shows that the cryptographic algorithm does not rely on pairing operations and is much more etticient than other algorithms. In addition, it suits well to applications in environments where resources are constrained, such as wireless sensor networks and ad hoc networks.展开更多
文摘Background It is still controversial whether percutaneous coronary intervention with drug-eluting stent （DES） is safe and effective compared to coronary artery bypass graft surgery （CABG） for unprotected left main coronary artery （ULMCA） disease at long-term follow up （≥3 years）. Methods Eligible studies were selected by searching PubMed, EMBASE, and Cochrane Library up to December 6, 2016. The primary endpoint was a composite of death, myocardial infarction （MI） or stroke during the longest follow-up. Death, cardiac death, MI, stroke and repeat revascularization were the secondary outcomes. Results Four randomized controlled trials and twelve adjusted observational studies involving 14,130 patients were included. DES was comparable to CABG regarding the occurrence of the primary endpoint （FIR = 0.94, 95% CI： 0.86-1.03）. Besides, DES was significantly associated with higher incidence of MI （HR = 1.56, 95% CI： 1.09-2.22） and repeat revascularization （HR = 3.09, 95% CI： 2.33-4.10） compared with CABG, while no difference was found between the two strategies regard as the rate of death, cardiac death and stroke. Furthermore, DES can reduce the risk of the composite endpoint of death, MI or stroke （HR = 0.80, 95% CI： 0.67-0.95） for ULMCA lesions with SYNTAX score ≤32. Conclusions Although with higher risk of repeat revascularization, PCI with DES appears to be as safe as CABG for ULMCA disease at long-term follow up. In addition, treatment with DES could be an alternative interventional strategy to CABG for ULMCA lesions with low to intermediate anatomic complexity.
文摘This paper presents the method for the performance calibration of AACMM （articulated arm coordinate measuring machines） according to ASME B89.4.22 Standard. The growing use of this class of measurement equipment has been accompanied by an absence of authorized laboratories to provide calibration certificates for its performance. Due to ASME B89.4.22 and VD12617-9 are nowadays the unique standards in the field of AACMM verification, IK4 Tekniker has compared both of them in order to develop internal test procedures to yield reliable performance calibration results. As a result, IK4 Tekniker has been recognized by the Spanish Accreditation Body （ENAC） in the field of AACMM calibration. Internal test procedures and uncertainty evaluation analysis have been developed as well as ENAC certificated reference test equipments have been acquired to ensure a suitable AACMM calibration process.
文摘The framework of digital signature based on qualified certificates and X. 509 architecture is known to have many security risks. Moreover, the fraud prevention mechanism is fragile and does not provide strong guarantees that can be necessary for flow of legal documents. Mediated signatures have been proposed as a mechanism to effectively disable signature cards. In this paper we propose further mechanisms that can be applied on top of mediated RSA, compatible with the standard format, but providing security guarantees even in the case when RSA becomes broken or the keys are compromised. The solution is immune tokleptographic attacks as only deterministic algorithms are used on user＇s side.
文摘In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource utilization, poor innovation ability, etc. And we point out the problems and challenges faced by traditional standards library in the network environment. The standards library must redesign the organization structure and business process radically so that standards library could improve the service model, enhance the service quality and utilization rate of various document resources.
基金the National Natural Science Foundation of China （Nos. 61572303, 61363080, and 61272436）, the Foundation of State Key Laboratory of Information Security （No. 2015-MS-10）, and the Foundation of Basic Research of Qinghai Province, China （No. 2016-ZJ-776）
文摘Hybrid signcryption is an important technique signcrypting bulk data using symmetric encryption. In this paper, we apply the technique of certificateless hybrid signcryption to an elliptic-curve cryptosystem, and construct a low-computation certificateless hybrid signcryption scheme. In the random oracle model, this scheme is proven to have indistinguishability against adaptive chosen-ciphertext attacks （IND-CCA2） under the elliptic-curve computation Diffie-Hellman assumption. Also, it has a strong existential unforgeability against adaptive chosen-message attacks （sUF-CMA） under the elliptic-curve discrete logarithm assumption. Analysis shows that the cryptographic algorithm does not rely on pairing operations and is much more etticient than other algorithms. In addition, it suits well to applications in environments where resources are constrained, such as wireless sensor networks and ad hoc networks.
