Robustness as a criterion for use of hollow clay masonry units in seismic zones: an attempt to propose the measure

In order to provide adequate seismic behavior of masonry walls, local brittle failure of masonry units in the most stressed zones of structural walls should be prevented. Although robust behavior is required by the code, no specifications are given regarding the criteria to fulfill this requirement. To propose such criteria, a series of 28 masonry walls, built with six different types of hollow clay masonry units, currently available on the market, have been tested by subjecting them to cyclic lateral load at two levels of constant precompression. Besides, the strength characteristics of the units, like compressive strength orthogonal and parallel to the bed joints and tensile and shear strength of the units have been determined by standardized and specifically designed testing procedures. By correlating the parameters of seismic resistance of the walls and strength characteristics of the units, no specific indicator for robustness could have been determined on the basis of the mechanical characteristics of the tested units. It has been found that in all cases the level of precompression, i.e. the ratio between the compressive stresses in the walls and the compressive strength of masonry, represents the governing parameter.     

A novel maximum power point tracker based on analog and digital control loops

In this paper, a new maximum power point tracking (MPPT) system for photovoltaic applications is presented. The proposed system consists of two analog loops, a current and a voltage loop, built around a boost converter and a digital loop for the computation of the maximum power point. The analog loops provide a fast response to sudden changes of irradiance conditions while the digital loop, enhancing the accuracy, allows the implementation of various MPPT algorithms and facilitates the integration of additional control and monitoring features. Different existing systems are simulated and compared. A small signal model for the proposed system is developed and a novel compensation method is found. The compensation is designed in such a way that it makes the system independent of the input panel used and also of the load connected at the output. In order to have fast simulation results, a macromodel is developed allowing comparison between different algorithms. Furthermore the “perturb and observe” (P&O) algorithm is improved to obtain a better response for changing irradiance conditions.     

Surface enhanced Raman scattering spot tests: a new insight on Feigl's analysis using gold nanoparticles

Traditional Feigl's spot tests can be greatly improved with the aid of gold nanoparticles and Raman probes, by monitoring the changes in the surface enhanced Raman scattering (SERS) of the analytes directly applied on a filter paper previously impregnated with the selective organic reagent. As a proof of concept, diphenylthiocarbazone (dithizone) was treated with citrate stabilized gold nanoparticles and employed in paper spot tests for a variety of transition and heavy metal ions. Below 10(-5) mol L(-1), only mercury(II) ions were able to displace the dithizone molecules from the "coordination shell" of the gold nanoparticles, leading to a systematic decay of the Raman signals. Because of the huge enhancement of the dithizone vibrational peaks, the SERS spot tests allowed the detection of picograms of Hg(2+) ions.     

Detection of Damaged Tool in Injection Molding Process with Acoustic Emission

ABSTRACT

The measurement of acoustic emission (AE) signals during injection molding of polypropylene with new and damaged mold is presented. The damaged injection mold was fitted with a steel insert with cracks induced by laser surface heat treatment. Two resonant piezoelectric AE sensors were attached to the mold via AE waveguides. To improve the mold integrity prediction with smaller defects, AE signal frequency characteristics and a measure of AE signal amplitude probability distribution are implemented. A 5-dimensional feature vector with real-valued explanatory variables is proposed, providing the defining points in an appropriate multidimensional space to characterize the state of injection molding tool. Feature vectors are classified with neural network pattern recognition. The results confirm that presented AE technique offers characterizing the integrity of molds also with resonant sensors.     

Transparent Plasmonic Nanowire Electrodes via Self‐Organised Ion Beam Nanopatterning

A self‐organised approach for the synthesis of transparent metal nanowire arrays is based on defocused ion beam sputtering. The nanowire arrays, supported on low‐cost dielectric substrates (glass slides), feature a dual functionality: they exhibit anisotropic conductivity, with sheet resistances which are reduced in comparison to those of transparent conductive oxides, and additionally they support localised plasmon resonances. The latter represents an attractive feature in view of plasmon enhanced photon harvesting applications, in which the nanostructured metal electrodes are employed as an alternative to conventional transparent conductive oxides.     

An economic model for the appraisal and selection of energy supply system

Economic evaluation of different energy supply systems (district or local heating by natural gas) in Serbia is considered in this paper. According to variety of Serbian settlements (in density, size and layout of buildings) model which has ability to represent their different characteristics is formed. Model is based on identification of smaller urban areas with identical or similar characteristics and their representations with one of predefined nominal urban areas. For various nominal urban areas preferred type of energy supply system was selected. Obtained results formed matrix of preferred type of energy supply system (district or local heating) for different urban structures. This models’ matrix could be simple and useful tool for initial decision about energy supply system.     

Cardiac Toxicity Associated with Immune Checkpoint Inhibitors: A Systematic Review

Immune checkpoint inhibitors (ICIs) are an important advancement in the field of cancer treatment, significantly improving the survival of patients with a series of advanced malignancies, like melanoma, non-small cell lung cancer (NSCLC), hepatocellular carcinoma (HCC), renal cell carcinoma (RCC), and Hodgkin lymphoma. ICIs act upon T lymphocytes and antigen-presenting cells, targeting programmed cell death protein 1 (PD1), programmed cell death protein ligand 1 (PD-L1), and cytotoxic T-lymphocyte antigen 4 (CTLA-4), breaking the immune tolerance of the T cells against malignant cells and enhancing the body’s own immune response. A variety of cardiac-adverse effects are associated with ICI-based treatment, including pericarditis, arrhythmias, cardiomyopathy, and acute coronary syndrome, with myocarditis being the most studied due to its often-unexpected onset and severity. Overall, Myocarditis is rare but presents an immune-related adverse event (irAE) that has a high fatality rate. Considering the rising number of oncological patients treated with ICIs and the severity of their potential adverse effects, a good understanding and continuous investigation of cardiac irAEs is of the utmost importance. This systematic review aimed to revise recent publications (between 2016–2022) on ICI-induced cardiac toxicities and highlight the therapeutical approach and evolution in the selected cases.     

Mitochondrial DNA Together with miR-142-3p in Plasma Can Predict Unfavorable Outcomes in Patients after Acute Myocardial Infarction

Myocardial infarction is one of the leading causes of death worldwide, despite numerous efforts to find efficient prognostic biomarkers and treatment targets. In the present study, we aimed to assess the potential of six microRNAs known to be involved in cardiovascular diseases, cell-free DNA (cfDNA), and mitochondrial DNA (mtDNA) circulating in plasma to be used as prognostic tools for the occurrence of unfavorable outcomes such as major adverse cardiovascular events (MACE) after acute ST-segment elevation myocardial infarction (STEMI). Fifty STEMI patients were enrolled and monitored for 6 months for the occurrence of MACE. Plasma was collected at three time points: upon admission to hospital (T₀), at discharge from hospital (T₁), and 6 months post-STEMI (T₆). Plasma levels of miR-223-3p, miR-142-3p, miR-155-5p, miR-486-5p, miR-125a-5p, and miR-146a-5p, as well as of cfDNA and mtDNA, were measured by RT-qPCR. Results showed that the levels of all measured miRNAs, as well as of cfDNA and mtDNA, were the most increased at T₁, compared to the other two time points. In the plasma of STEMI patients with MACE compared to those without MACE, we determined increased levels of miRNAs, cfDNA, and mtDNA at T_1. Hence, we used the levels of all measured parameters at T₁ for further statistical analysis. Statistical analysis demonstrated that all six miRNAs and cfDNA plus mtDNA levels, respectively, were associated with MACE. The minimal statistical model that could predict MACE in STEMI patients was the combination of mtDNA and miR-142-3p levels, as evidenced by ROC analysis (AUC = 0.97, p < 0.001). In conclusion, the increased plasma levels of mtDNA, along with miR-142-3p, could be used to predict unfavorable outcomes in STEMI patients.