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In this paper, a comparative statistical analysis of some performance indicators from the health system at SCJU Craiova and SJU Slatina is made in the period 2010-2021. Also, the correlations between the average duration of hospitalization, the bed utilization rate, the number of cases and the case complexity index for each hospital are studied. It is found that there are similarities, but also statistically significant differences between the two analyzed hospitals. Thus, it turns out that there are no significant differences between the bed utilization rate and the complexity index between the two hospitals, but there are statistically significant differences at a significance threshold of 5% between the average duration of hospitalization and the number of cases registered at the two hospitals analyzed. Moreover, the case complexity index is strongly negatively correlated with the bed utilization rate and with the number of cases in both hospitals, but positively correlated with the average duration of hospitalization at SCJU Craiova and weakly negatively correlated at SJU Slatina.
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The paper studies new materials for brake disks used in car manufacturing. The materials used in the manufacturing of the brake disc must adapt and correlate with the challenges of current society. There is a tremendous interest in the development of a material that has high strength, good heat transfer, corrosion resistance and low density, in order to withstand high-breaking forces, high heat and various adverse environment. Low-density materials improve fuel efficiency and environmental impact. Complex concentrated alloys (CCA) are metallic element mixtures with multi-principal elements, which can respond promisingly to this challenge with their variety of properties. Several compositions were studied through thermodynamic criteria calculations (entropy of mixing, enthalpy of mixing, lambda coefficient, etc.) and CALPHAD modeling, in order to determine appropriate structures. The selected compositions were obtained in an induction furnace with a protective atmosphere and then subjected to an annealing process. Alloy samples presented uniform phase distribution, a high-melting temperature (over 1000 °C), high hardness (1000-1400 HV), good corrosion resistance in 3.5 wt.% NaCl solution (under 0.2 mm/year) and a low density (under 6 g/cm3).
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Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate.
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Complex concentrated alloys (CCAs) are a new family of materials with near equimolar compositions that fluctuate depending on the characteristics and destination of the material. CCAs expand the compositional limits of the traditional alloys, displaying new pathways in material design. A novel light density Al5Cu0.5Si0.2Zn1.5Mg0.2 alloy was studied to determine the structural particularities and related properties. The alloy was prepared in an induction furnace and then annealed under a protective atmosphere. The resulted specimens were analysed by chemical, structural, mechanical, and corrosion resistance. The structural analyses revealed a predominant FCC and BCC solid solution structure. The alloy produced a compression strength of 500-600 MPa, comparable with conventional aluminium alloys. The corrosion resistance in 3.5% NaCl solution was 0.3424 mm/year for as-cast and 0.1972 mm/year for heat-treated alloy, superior to steel, making the alloy a good candidate for marine applications.
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Malignant melanoma is a melanocytic neoplasm with a steadily increasing incidence worldwide. In order to define a proper diagnostic protocol and to establish an accurate prognostic method for the disease, specific biomarkers are of notable importance. Their contribution is also significant in the treatment of melanoma for the improvement of newer and more targeted therapeutic approaches. To emphasize the importance of specific immune markers in the diagnosis of melanoma, immunohistochemical analysis was performed on 56 formalin-fixed paraffin-embedded cutaneous melanomas. Besides the traditional prognostic factors, depth of invasion and mitotic rate, the markers tested in the present study were S100 protein family, Melan A, Ki67 and HMB-45. The present results indicated that immunocytochemistry represents a valuable test in the diagnosis and treatment of malignant melanoma and each biomarker had different associations with the progression and prognosis of the disease. Patients with S100 expression were 4.83 times (95% CI=1.2-20.8) more likely to suffer a relapse, whereas patients with a Ki67 expression of >30% had a 5.41-fold higher risk (95% CI=1.3-22.0). The correlation between S100 and the Breslow depth was statistically significant (r-value: 0.43; P=0.027). In addition, the importance of a multidisciplinary team including a plastic surgeon, anatomopathologist and oncologist was highlighted.
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The continuous development of society has increased the demand for critical raw materials (CRMs) by using them in different industrial applications. Since 2010, the European Commission has compiled a list of CRMs and potential consumption scenarios with significant economic and environmental impacts. Various efforts were made to reduce or replace the CRM content used in the obtaining process of high-performance materials. Complex concentrated alloys (CCAs) are an innovative solution due to their multitude of attractive characteristics, which make them suitable to be used in a wide range of industrial applications. In order to demonstrate their efficiency in use, materials should have improved recyclability, good mechanical or biocompatible properties, and/or oxidation resistance, according to their destination. In order to predict the formation of solid solutions in CCAs and provide the optimal compositions, thermodynamic and kinetic simulations were performed. The selected compositions were formed in an induction furnace and then structurally characterized with different techniques. The empirical results indicate that the obtained CCAs are suitable to be used in advanced applications, providing original contributions, both in terms of scientific and technological fields, which can open new perspectives for the selection, design, and development of new materials with reduced CRM contents.