Evaluation of Methodologies for Assessing Self-Healing Performance of Concrete with Mineral Expansive Agents: An Interlaboratory Study

Self-healing concrete has the potential to optimise traditional design approaches; however, commercial uptake requires the ability to harmonize against standardized frameworks. Within EU SARCOS COST Action, different interlaboratory tests were executed on different self-healing techniques. This paper reports on the evaluation of the effectiveness of proposed experimental methodologies suited for self-healing concrete with expansive mineral additions. Concrete prisms and discs with MgO-based healing agents were produced and precracked. Water absorption and water flow tests were executed over a healing period spanning 6 months to assess the sealing efficiency, and the crack width reduction with time was monitored. High variability was reported for both reference (REF) and healing-addition (ADD) series affecting the reproducibility of cracking. However, within each lab, the crack width creation was repeatable. ADD reported larger crack widths. The latter influenced the observed healing making direct comparisons across labs prone to errors. Water absorption tests highlighted were susceptible to application errors. Concurrently, the potential of water flow tests as a facile method for assessment of healing performance was shown across all labs. Overall, the importance of repeatability and reproducibility of testing methods is highlighted in providing a sound basis for incorporation of self-healing concepts in practical applications

Management of coronary artery disease patients in Latvia compared with practice in Central-Eastern Europe and globally: Analysis of the CLARIFY registry

BACKGROUND AND OBJECTIVE: Management of outpatients with stable coronary artery disease (CAD) is important in secondary prevention. The objective was to describe differences in the characteristics of CAD patients in Latvia compared with other countries. MATERIALS AND METHODS: CLARIFY is an ongoing international, prospective, observational, longitudinal registry of outpatients with CAD. Data regarding treated outpatients with established CAD from the CLARIFY registry in Latvia (n=120) were compared with those from the rest of Central-Eastern Europe (CEE) (n=2888) and worldwide (n=33,163). RESULTS: Patients in Latvia had a larger waist circumference (101 [95-109] vs. 99 [91-106] in CEE, 96.5 [88-105]cm worldwide; P=0.023 and P<0.001, respectively) and higher blood pressure (systolic: 138.28±17.13 vs. 133.77±16.47 in CEE and 130.97±16.65mm Hg worldwide, P=0.003 and P<0.001; diastolic: 82.98±8.58 vs. 80.01±9.61 in CEE and 77.22±9.97mm Hg worldwide, P<0.001 and P<0.001, respectively). Body mass index in Latvia did not differ significantly from that in CEE (P=0.422), but was higher than worldwide (28.8 [26.2-32.0] vs. worldwide 27.3 [24.8-30.3]kg/m(2), P<0.001). The history of percutaneous coronary intervention was more frequent in Latvia (74.17% vs. 59.34% in CEE and 58.61% worldwide, P=0.001 and P<0.001, respectively). Latvian patients more frequently used aspirin (97.50% in Latvia vs. 89.75% in CEE and 87.64% worldwide, P=0.005 and P=0.001, respectively). CONCLUSIONS: Latvian CAD patients are well managed in terms of aspirin use and frequency of percutaneous coronary intervention. Control of obesity and high BP is poorer and needs further improvement

Analyses of phase change materials’ efficiency in warm-summer humid continental climate conditions

The usage of phase change materials (PCMs) is a way to store excess energy pro- duced during the hot time of the day and release it during the night thereby reducing the overheating problem. While, in Latvian climate conditions overheating is not a big issue in traditional buildings since it happens only a couple of weeks per year air conditioners must still be installed to maintain thermal comfort. The need for cooling in recently built office buildings with large window area can increase signi cantly. It is therefore of great interest if the ther- mal comfort conditions can be maintained by PCMs alone or with reduced maximum power of installed cooling systems. Our initial studies show that if the test building is well-insulated (nec- essary to reduce heat loss in winter), phase change material is not able to solidify fast enough during the relatively short night time. To further investigate the problem various experimental setups with two different phase change materials were installed in test buildings. Experimental results are compared with numerical modelling made in software COMSOL Multiphysics. The effectiveness of PCM using different situations is widely analysed

Synthesis of N-(5-chloro-6-(quinolin-3-yloxy)pyridin-3-yl) benzenesulfonamide derivatives as non-TZD peroxisome proliferator-activated receptor γ (PPARγ) agonist

The thiazolidinediones (TZDs) are a class of oral antidiabetic drugs that improve insulin sensitivity in patients with type 2 diabetes. Although the mechanism by which the TZDs lower insulin resistance is unclear, they are known to target the peroxisome proliferator-activated receptor γ (PPARγ), a nuclear hormone receptor. Ligands for PPARγ regulate adipocyte production and secretion of fatty acids as well as glucose metabolism, resulting in increased insulin sensitivity in adipose tissue, liver, and skeletal muscle. However, TZDs have several adverse effects, including weight gain and liver toxicity. Herein we report identification of non-TZD PPARγ agonists which exhibit beneficial effects similar to that of TZDs in animal models, but without the associated adverse effects. © 2012 Elsevier Masson SAS. All rights reserved

Synthesis of N-(6-(4-(Piperazin-1-yl)phenoxy)pyridin-3-yl) benzenesulfonamide Derivatives for the Treatment of Metabolic Syndrome

Metabolic syndrome is a widely prevalent multifactorial disorder associated with an increased risk of cardiovascular disease and type 2 diabetes mellitus. High plasma levels of insulin and glucose due to insulin resistance are a major component of the metabolic disorder. Thiazolidinediones (TZDs) are potent PPARγ ligand and used as insulin sensitizers in the treatment of type 2 diabetes mellitus. They are potent insulin-sensitizing agents but due to adverse effects like hepatotoxicity, a safer alternative of TZDs is highly demanded. Here we report synthesis of N-(6-(4-(piperazin-1-yl)phenoxy)pyridin-3-yl)benzenesulfonamide derivatives as an alternate remedy for insulin resistance

Design and synthesis of non-TZD peroxisome proliferator-activated receptor γ (PPARγ) modulator

Thiazolidinediones (TZDs) are an important class of compound used for the treatment of type 2 diabetes, targeting the peroxisome proliferator-activated receptor γ (PPARγ). Drug-induced hepatotoxicity, edema, and weight gain are the main concerns associated with TZDs. It was unclear whether the side effects observed are target mediated or compound mediated, but most of the TZDs activate PPARγ. This obliged developing of a new diverse class of ligands as antihyperglycemic agents including non-TZD PPAR ligands that could be highly effective, safe, and devoid of side effects. Here, we report the design and synthesis of N-(5-chloro-6-((1-phenylpiperidin-4-yl)oxy)pyridin-3-yl) benzenesulfonamide derivatives as non-TZD PPARγ modulators. © Springer Science+Business Media 2013

A review of the legal framework in shallow geothermal energy in selected European countries: Need for guidelines

© 2018 Elsevier LtdOver the past years, the installations of Shallow Geothermal Energy (SGE) systems are increasing throughout Europe, and it is indicating that a specific and detailed legal framework is necessary. Towards this direction, this paper consists of an overview of legislation issues on SGE at European level, based on concise reviews from fourteen countries, i.e., Croatia, Cyprus, France, Greece, Italy, Latvia, Lithuania, Poland, Portugal, Serbia, Slovenia, Spain, Sweden, and Turkey. Said reviews discuss key national legislation as well as experts’ experience in the procedure of SGE integration. Legal and technical issues are also critically discussed for all involved countries, both individually and collectively. Findings show that high diversity exists on legislation provisions as well as on regulations, standards, and institutional support amongst European countries. The latter acts as an effective barrier for the further development of the SGE market; therefore indicating the need for a common approach. Increase of awareness, need for standardization, improvement of legal framework, and administration procedures and permitting, are essential steps in moving forward and supporting the effectiveness of design, construction, maintenance, and operation of SGE systems