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In this paper, an IMS LD engine based on a Petri net model that represents the operational semantics of units of learning based on this specification is presented. The Petri nets of this engine, which is called OPENET4LD, verify the structural properties that are desirable for a learning flow and also facilitate the adaptation of the engine if potential changes in the IMS LD specification were proposed. Furthermore, OPENET4LD has an open and flexible architecture based on a set of ontologies that describe both the semantics of the Petri nets execution and the semantics of each learning flow component of IMS LD. Furthermore, the implementation of this architecture has been exhaustively validated with a number of UoLs that are compliant with the levels A and B of IMS LD.  相似文献   
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Parkinson's disease (PD) patients often develop dementia, and Alzheimer's disease (AD) patients frequently develop parkinsonian signs. The apolipoprotein E epsilon4 allele is associated with increased risk and earlier onset of AD. We studied 137 unrelated white PD patients. Those with epsilon4 had the earliest onset (52.7 +/- 9.8 years), epsilon3/epsilon3 patients had an intermediate onset (56.1 +/- 11.1 years), and those with epsilon2 had the latest onset (59.1 +/- 13.4 years). The age at onset distribution for epsilon4/epsilon- was significantly earlier than for epsilon3/epsilon3 and epsilon2/epsilon3. These preliminary results suggest that apolipoprotein E genotypes modulate the age at onset of PD.  相似文献   
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A retrospective analysis of our experience in the treatment of hiliary cholangiocarcinoma or Klatskin tumor was performed with the aim of evaluating the morbi-mortality and prognosis of its treatment to thereby determine the usefulness of the different therapeutic options. From 1989 to 1997, 51 patients diagnosed with hiliary cholangiocarcinoma were treated in our hospital. Surgery was indicated in 16 with curative aims (group I) while palliative treatment with percutaneous biliary drainage was indicated in 35 (group II). Biliary resection was carried out in 8 patients being associated with hepatic resection in 4 (group IA) and in 8 patients undergoing liver transplantation (group IB). Clinico-epidemiologic data and hospital stay were similar in all the groups. The frequency of complications was similar in groups I and II although the frequency of cholangitis (49%) in group II was noticeable. The percentage of readmissions was also greater in group II (12 vs 46%, respectively; p = 0.03) with prosthesis obstruction being the most frequent cause. Accumulated survival at 1, 2, and 3 years in group I was 84, 64 and 48% with a median survival of 33 months, while in group II the median survival was of 6 months with no patient surviving more than 2 years (p = 0.0001). When groups IA and IB were compared, greater frequency of complications in groups IA (100 vs 37%; p = 0.002), similar frequency of readmissions (87 vs 75%; p = NS), median survival greater in group IB (12.5 months vs 48 months) and significantly higher actuarial survival in group IB (48% in 2 years vs 83% to 2 years; p = 0.02) was observed. In conclusion, surgery is the treatment of choice in hiliary cholangiocarcinoma whenever possible, given the greater survival without a significant increase in morbimortality. Likewise, we consider that liver transplantation is a useful option in the treatment of patients with cholangiocarcinoma type IV of Bismuth.  相似文献   
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The results of experimental investigations of tubular alloy 01570 specimens under complex loading are presented. The vector and scalar properties of the material are investigated at various temperatures and fracture angles. V. G. Zubchaninov's hypothesis that active loading processes at fracture angles to 90° can be considered quasisimple is confirmed.Translated from Problemy Prochnosti, No. 3, pp. 35–39, March, 1993.  相似文献   
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Blanc  Soline  Lahmadi  Abdelkader  Le Gouguec  Kévin  Minier  Marine  Sleem  Lama 《Wireless Networks》2022,28(8):3453-3476
Wireless Networks - Cryptographic algorithms that can provide both encryption and authentication are increasingly required in modern security architectures and protocols (e.g. TLS v1.3). Many...  相似文献   
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