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The Quantitative Structure-Property Relationships (QSPRs) based on Graph or Network Theory are important for predicting the properties of polymeric systems. In the three previous papers of this series (Polymer 45 (2004) 3845-3853; Polymer 46 (2005) 2791-2798; and Polymer 46 (2005) 6461-6473) we focused on the uses of molecular graph parameters called topological indices (TIs) to link the structure of polymers with their biological properties. However, there has been little effort to extend these TIs to the study of complex mixtures of artificial polymers or biopolymers such as nucleic acids and proteins. In this sense, Blood Proteome (BP) is one of the most important and complex mixtures containing protein polymers. For instance, outcomes obtained by Mass Spectrometry (MS) analysis of BP are very useful for the early detection of diseases and drug-induced toxicities. Here, we use two Spiral and Star Network representations of the MS outcomes and defined a new type of TIs. The new TIs introduced here are the spectral moments (πk) of the stochastic matrix associated to the Spiral graph and describe non-linear relationships between the different regions of the MS characteristic of BP. We used the MARCH-INSIDE approach to calculate the πk(SN) of different BP samples and S2SNet to determine several Star graph TIs. In the second step, we develop the corresponding Quantitative Proteome-Property Relationship (QPPR) models using the Linear Discriminant Analysis (LDA). QPPRs are the analogues of QSPRs in the case of complex biopolymer mixtures. Specifically, the new QPPRs derived here may be used to detect drug-induced cardiac toxicities from BP samples. Different Machine Learning classification algorithms were used to fit the QPPRs based on πk(SN), showing J48 decision tree classifier to have the best performance. These results suggest that the present approach captures important features of the complex biopolymers mixtures and opens new opportunities to the application of the idea supporting classic QSPRs in polymer sciences.  相似文献   
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The evaluation of the failure pressure of the containment building of a large dry PWR-W three loops nuclear power plant, based on computer numerical simulation, is described in this paper. The proposed method considers fully three-dimensional finite element models in order to take into account the effect of the most significant structural characteristics (presence of three buttresses, penetrations, additional reinforcement around the penetrations, etc.), the lack of symmetry of the forces generated by the prestressing system, as well as the nonlinear behaviour of the materials and the sensitivity of the results to uncertainties associated with several parameters. The computational model is completely described, including the constitutive equations for the concrete, the reinforcing steel and prestressing tendons, the spatial discretization—isoparametric elements including the reinforcement are used. The structural models and the analyses performed for their calibration are also described. The influence on the failure pressure of incorporating the foundation slab in the structural model, and the influence of the thermal effects, are discussed. One of the conclusions of the numerical study is that the failure process can be appropriately simulated by means of a structural model which does not include either the foundation slab or the thermal effects. Finally, results of a probabilistic simulation of the failure pressure are given.  相似文献   
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OBJECTIVES: To determine the efficacy and complications of continuous epidural perfusion of bupivacaine, adrenaline and fentanyl in the relief of pain during first and second stage labour during vaginal birth. PATIENTS AND METHODS: Between January 1990 and March 1993 we used continuous epidural perfusion for control of pain during labor in 1307 women. The solution administered through an epidural catheter and maintained until expulsion was one 10 ml bolus of bupivacaine 0.25% with adrenaline 1:200,000 and fentanyl 25 micrograms followed by continuous perfusion of bupivacaine 0.0625% with adrenaline 1:200,000 and fentanyl 2 micrograms/ml at an infusion rate of 12 ml/h. When analgesia was insufficient, a bolus of local anesthetic was administered or a pudendal block was carried out. RESULTS: Ninety-two percent of the birthing women reported good analgesic effect during the first stage; for 7% the effect was fair and for 0.55% it was poor. During the second stage 88% reported satisfactory analgesia, and 8% fair or poor. Assessment was not possible for the remaining women, who underwent cesarean sections. Complications were few and easily controllable. CONCLUSIONS: Maintenance of epidural perfusion with 0.0625% bupivacaine with adrenaline 1:200,000 and fentanyl 2 micrograms/ml provides sufficient analgesia during all stages of childbirth.  相似文献   
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Applied Intelligence - The17 Sustainable Development Goals (SDGs) established by the United Nations Agenda 2030 constitute a global blueprint agenda and instrument for peace and prosperity...  相似文献   
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