Fatigue assessment and deterioration effects on masonry elements: A review of numerical models and their application to a case study

Safety assessment with respect to seismic and vertical loads of existing and very old masonry structures is currently a central topic for the scientific engineering community. In particular, there are many ancient bridges still in service that are subjected to higher and more frequent cyclic loads. For these structures, it is important to determine the actual fatigue strength, rather than the ultimate carrying capacity. In this way the remaining service life, with possible traffic load limitations, may be estimated. This paper reports an updated review of the state-of-the art on recently published fatigue models that account for deterioration effects under cyclic loads. In addition, results related to fatigue performance of a bridge are shown and comments are provided. The numerical comparisons among existing fatigue models reveal that the application of the available fatigue models is particularly problematic for ancient masonry elements, where appropriate stress-life curves are required

Fatigue behaviour and residual service life of existing masonry arch bridges

The conservation and safety assessment of old masonry arch bridges represent nowadays a research field of considerable interest. Most of them are testimonies of the past with a significant historical and cultural value, and represent nowadays a large part of the transport infrastructures serving strategic link for roads and railways networks. In many cases their masonry primary elements are already deteriorated due to weather conditions and to the effects of cyclic traffic loads that are increased in both the frequency and the intensity with respect to the past. Even if the ultimate load is not reached, the cumulated damage along with the localised deterioration can reach levels not acceptable leading the entire structure out of service. This paper is addressed to the fatigue assessment of old masonry arch bridges with particular attention to the residual service life evaluation of the arch elements. Unlike of metals and metallic structures, little informations are available to date on the fatigue behaviour of masonry elements, also confirmed by the fact that there are no specific guidelines for assessing the fatigue limit and the residual life. The paper at first shows a critical review of the damage models for the fatigue performance assessment of masonry arch bridges. Then, an application to a case study is presented, where also the influence of intradosal C-FRP reinforcement on the residual service life and the ultimate capacity is discussed

Evaluation of milk production and some blood parameters in lactating autochthonous goat extensively reared in Molise region

The trial, lasted 7 months and was performed on 60 lactating autochthonous goat populations (Montefalcone and Valfortorina) extensively reared in Molise Region. Goat milk yield and composition, and pasture chemical and floristic composition were recorded monthly. At the beginning (30d), at half (105d) and at the end (210d) of trial body weight and body condition score (BCS) were recorded; besides jugular blood samples were taken at 30, 105 e 210 d to determined the following parameters: glucose, total protein, albumin, urea, triglycerides, total and HDL cholesterol, NEFA, calcium, magnesium, sodium and potassium. The two populations showed a milk yield of 275 kg e 258 kg (Montefalcone e Valfortorina goat, respectively) throughout 180 days of lactation, which was similar or higher than mean milk yield of other goat breeds (Sarda, Ionica, Argentata dell'Etna). BCS increased significantly (P<0.01) during lactation in both populations. Blood parameters displayed significant changes (P<0.01) during the trial in Montefalcone goat for glucose, albumin, urea, triglycerides, total and HDL cholesterol, NEFA, sodium and potassium instead Valfortorina goat showed significant differences in total protein, urea, total and HDL cholesterol, NEFA, magnesium, sodium (P<0.01) and albumin and potassium (P<0.05). In both population, milk yield and quality showed promising results for autochthonous goats preservation

Fatigue Assessment and Deterioration Effects on Masonry Elements: A Review of Numerical Models and Their Application to a Case Study

Safety assessment with respect to seismic and vertical loads of existing and very old masonry structures is currently a central topic of engineering scientific community. In particular, there are many ancient bridges still in service subjected, respect to the past, to higher and more frequent cyclic loads. For these structures it is really important to determine, rather than the ultimate carrying capacity, the actual fatigue strength. In this way the remaining service life, with also possible traffic load limitations, may be estimated. This paper reports an updated review of state of the art about the recent fatigue models published in the literature, taking also into account deterioration effects under cyclic loads. In addition, some results related to the fatigue performance of a case study are shown and commented. The numerical comparisons reveal that the application of the available fatigue model is particular problematic in the case of ancient masonry elements, where appropriate stress-life curves are required

Fibrinogen: a novel predictor of responsiveness in metastatic melanoma patients treated with bio-chemotherapy: IMI (italian melanoma inter-group) trial

PURPOSE: To evaluate a panel of pretreatment clinical and laboratory parameters in metastatic melanoma (MM) in order to verify their impact on response and survival in a single prospective multi-institutional phase III study comparing out-patient chemotherapy (CT) vs bioCT. METHODS: A total of 176 patients were randomised to receive CT (cisplatin, dacarbazine, optional carmustine) or bioCT (the same CT followed by subcutaneous IL-2 plus intramuscular α-IFN-2b). Pretreatment total leucocytes, lymphocytes, eosinophyls, C-reactive protein (CRP), lactate dehydrogenase (LDH), erytrosedimentation rate (ESR), and fibrinogen were analyzed. Some clinical parameters (performance status, age, sex, and disease site) were also considered. As we found a positive trend for bio-CT with no statistical significance in OR (25.3% vs 20.2%) and OS (11 Mo vs 9.5 Mo), all analyses are stratified by treatment arm. RESULTS: In univariate analysis, higher value of lymphocytes percentage (P < .0001), lower value of total leucocytes (P=.005), CRP (P=.003), LHD (P < .0001), ESR (P < .027), fibrinogen (P < .0001), and no liver disease were strongly related to a better survival. In a multivariate analysis, using the Cox proportional hazards model, only fibrinogen (P=.004), LDH (P=.009) and liver disease (P=.04) were found to have an independent role on clinical outcome in metastatic melanoma patients. CONCLUSION: Liver disease and higher LDH and fibrinogen levels had an important impact on survival in MM patients. In particular, fibrinogen has been recently reconsidered both for its determinant role in the host hemostatic system, and for its capability to provide protection against NK and LAK-cell-induced lysis. These observations could have some important implications for therapeutic approaches, in particular when immunological strategies are used

life threatening acute myocardial infarction due to left main dissection during radiofrequency transcatheter ablation of atrial tachycardia

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