RILEM TC 247-DTA round robin test: sulfate resistance, alkali-silica reaction and freeze–thaw resistance of alkali-activated concretes

The RILEM technical committee TC 247-DTA ‘Durability Testing of Alkali-Activated Materials’ conducted a round robin testing programme to determine the validity of various durability testing methods, originally developed for Portland cement based-concretes, for the assessment of the durability of alkali-activated concretes. The outcomes of the round robin tests evaluating sulfate resistance, alkali-silica reaction (ASR) and freeze–thaw resistance are presented in this contribution. Five different alkali-activated concretes, based on ground granulated blast furnace slag, fly ash, or metakaolin were investigated. The extent of sulfate damage to concretes based on slag or fly ash seems to be limited when exposed to an Na2SO4 solution. The mixture based on metakaolin showed an excessive, very early expansion, followed by a dimensionally stable period, which cannot be explained at present. In the slag-based concretes, MgSO4 caused more expansion and visual damage than Na2SO4; however, the expansion limits defined in the respective standards were not exceeded. Both the ASTM C1293 and RILEM AAR-3.1 test methods for the determination of ASR expansion appear to give essentially reliable identification of expansion caused by highly reactive aggregates. Alkali-activated materials in combination with an unreactive or potentially expansive aggregate were in no case seen to cause larger expansions; only the aggregates of known very high reactivity were seen to be problematic. The results of freeze–thaw testing (with/without deicing salts) of alkali-activated concretes suggest an important influence of the curing conditions and experimental conditions on the test outcomes, which need to be understood before the tests can be reliably applied and interpreted

Treatment of displaced intra-articular calcaneal fractures by ligamentotaxis: current concepts’ review

Introduction: A large variety of therapeutic modalities for calcaneal fractures have been described in the literature. No single treatment modality for displaced intra-articular calcaneal fractures has proven superior over the other. This review describes and compares the different percutaneous distractional approaches for intra-articular calcaneal fractures. The history, technique, anatomical and fracture considerations, limitations and the results of different distractional approaches reported in the literature are reviewed. Method: Literature review on different percutaneous distractional approaches for displaced intra-articular calcaneal fractures. Results: Eight studies in which application of a distraction technique was used for the treatment of calcaneal fractures were identified. Because of the use of different classification, techniques, and outcome scoring systems, a meta-analysis was not possible. A literature review reveals overall fair to poor result in 10-29% of patients. Ten up to 26% of patients are unable to return to work after percutaneous treatment of their fracture. A secondary arthrodesis has to be performed in 2-15% of the cases. Infectious complications occur in 2-15%. Some loss of reduction is reported in 4-67%. Conclusion: Percutaneous distractional reduction and fixation appears to be a safe technique with overall good results and an acceptable complication rate, compared with other treatment modalities for displaced intra-articular calcaneal fractures. A meta-analysis, based on Cochrane Library criteria is not possible, because of a lack of level 1 and 2 trials on this subject

Impact of Diabetes on Postinfarction Heart Failure and Left Ventricular Remodeling

Diabetes mellitus, the metabolic syndrome, and the underlying insulin resistance are increasingly associated with diastolic dysfunction and reduced stress tolerance. The poor prognosis associated with heart failure in patients with diabetes after myocardial infarction is likely attributable to many factors, important among which is the metabolic impact from insulin resistance and hyperglycemia on the regulation of microvascular perfusion and energy generation in the cardiac myocyte. This review summarizes epidemiologic, pathophysiologic, diagnostic, and therapeutic data related to diabetes and heart failure in acute myocardial infarction and discusses novel perceptions and strategies that hold promise for the future and deserve further investigation

Spectrum of PTCH mutations in Italian nevoid basal cell-carcinoma syndrome patients: identification of eleven novel alleles

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant genetic disease characterized by numerous basal cell carcinomas, odontogenic keratocysts of the jaws, palmar and plantal pits, skeletal abnormalities, and calcification of the falx cerebri. The gene responsible for this syndrome is the PTCH tumor suppressor gene encoding for the sonic hedgehog receptor. In this paper, we report thirteen novel mutations identified in the first screening of NBCCS patients in Italy. Except for p.T230P and p.F505_L506delinsLR, all the other mutations are predicted to determine a premature truncation of the protein

Spectrum of PTCH mutations in Italian nevoid basal cell-carcinoma syndrome patients: identification of eleven novel alleles

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant genetic disease characterized by numerous basal cell carcinomas, odontogenic keratocysts of the jaws, palmar and plantal pits, skeletal abnormalities, and calcification of the falx cerebri. The gene responsible for this syndrome is the PTCH tumor suppressor gene encoding for the sonic hedgehog receptor. In this paper, we report thirteen novel mutations identified in the first screening of NBCCS patients in Italy. Except for p.T230P and p.F505_L506delinsLR, all the other mutations are predicted to determine a premature truncation of the protein

Spectrum of PTCH mutations in Italian nevoid basal cell-carcinoma syndrome patients: Identification of thirteen novel alleles

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant genetic disease characterized by numerous basal cell carcinomas, odontogenic keratocysts of the jaws, palmar and plantal pits, skeletal abnormalities, and calcification of the falx cerebri. The gene responsible for this syndrome is the PTCH tumor suppressor gene encoding for the sonic hedgehog receptor. In this paper, we report thirteen novel mutations identified in the first screening of NBCCS patients in Italy. Except for p.T230P and p.F505_L506delinsLR, all the other mutations are predicted to determine a premature truncation of the protein