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The research work, through its structure, aims to achieve several objectives: following the evolution of the insurance market in Romania during the period 2015 - 2022, a period in which the pandemic generated by Covid-19 left its mark on several sectors of activity, the analysis the correlation between the indicators that define the insurance market and GDP/capita, and finally, with the help of the statistical program Eviews, we will create a multiple linear regression model.

The research aims to provide a new approach and insights into the nexus between economic growth and green energy by analyzing their direct, indirect, and total linkages at the European Union level (EU-27). To this end, an advanced empirical analysis performed by network analysis, as Gaussian Graphical Models, is carried out for the period 2012–2022 The originality of network analysis lies in the fact that it allows the simultaneous visualization of all the links between variables in a complex system of dependencies. The novelty of the paper is twofold: first, it addresses the issue of renewable energy in an innovative way that captures three key stages of the EU policy (renewables’ capacity; share of renewable energy; and final consumption); second, it advances the nexus analysis by considering technological investments. Empirical results have validated the vital role of increasing the share of renewable energy in achieving sustainability and reducing greenhouse gas emissions. Also, the Research & Development and Gross Value added in environmental goods and services sector are found to positively influence sustainable development. The results are useful for policymakers and managers of organizations to understand the relationships between these variables better and thus, achieve climate neutrality.

Pollution is being discussed more and more in the world. It is known that the production of Glass Fiber Reinforced Polyester (GRP) is a polluting process. Also, the implementation of GRP is a process that can cause various ailments to the personnel who apply it. Over time, boats made of GRP suffer degradation due to interaction with the environment: cracks, exfoliation of the outer layer of gelcoat, etc. These degradations must be remedied, operations that involve the application of substances that are also polluting. More and more traditional manufacturers of sports boats are replacing GRP with aluminum. This, although the process of obtaining it from the ore is not without toxic components, is less polluting and friendlier to the executors than GRP. In this paper, we seek to elucidate the advantages that aluminum has over GRP in the construction of sports boats.

The paper presents the experimental study of the influence of a 50 Hz extremely-low-frequency (ELF) electromagnetic field (EMF) on the growth of microalgae Chlorella vulgaris in a BG11 culture medium. Comparative experimental determinations carried out under reference conditions (microalgae growth without exposure to EMF) and with exposure to a homogeneous 50 Hz EMF of various intensities highlighted the fact that EMF has a major impact on both the growth speed and the nitrogen and phosphorus content of the obtained algal mass. Through spectrophotometry and gravimetric determinations, it was found that the lag time was reduced from approximately 8 h (reference) to approximately 6 h for EMF of 2 V/m, 4.5 h for EMF of 5 V/m, 3.2 h for EMF of 10 V/m, and 2.5 h for EMF of 15 V/m. In the stimulation with 15 V/m EMF, the maximum biomass growth rate was 2.75 times higher than the reference, leading to a 2-fold increase in the rate of exhaustion of nutrients, especially phosphorus, in the culture medium. The specific chemical analyses for N-NO3, total nitrogen TNb, and total phosphorus Pt highlighted that the N-NO3 content of the culture medium decreased by 58 mg/L/day at 15 V/m EMF compared to 43 mg/L for the reference. The Pt content decreased to 90% depletion after approximately 80 h for the reference culture medium, versus only 48 h of growth with exposure to 15 V/m ELF. The TNb content of the algal suspension in BG11 under the influence of 15 V/m EMF for 96 h of growth increased 14 times compared to the reference. This shows that nitrogen metabolization in the dispersed air was significantly stimulated. It was also found that the 50 Hz EMF also influences the nitrogen and phosphorus content of the increased algal mass. The results show the potential of EMF stimulation of Chlorella vulgaris growth, leading to an increased efficiency of algae growth reactors.

The basic idea of this study is based on the hypothesis that it is possible to obtain nanostructures by stimulating local chemical reactions. Starting with this hypothesis we assumed that it is possible to disperse some inorganic agent into the epoxy resin and stimulating the mixtures we could get some nano-structures what are changing the basic electric behaviour of the polymer matrix. We dissolved some metallic chlorides in DMF (dimethylformamide) and we mixed together the solution with the epoxy resin (the main component). Applying various external stimuli we get materials showing various properties, different from the epoxy resin properties. The electric photoconductivity is increased (in some cases) but the mechanical properties are damaged due the solvent presence into the polymer matrix. [ABSTRACT FROM AUTHOR]

The use of smart technologies and the Internet of Things (IoT) is becoming more and more popular in order to enhance the overall building performance by monitoring parameters related to occupants’ comfort and health in the built environment. A new modular, custom-made and replicable IoT system is proposed based on an Arduino development board (MKR WiFi 1010) connected to the Arduino IoT Cloud. An Application Programming Interface (API) enables the integration of this system with other possible ones, thus making the system modular, custom-made and replicable. A series of parameters were simultaneously monitored over a 7-day period in two office spaces and a photovoltaic (PV)-testing laboratory. While the meteorological and comfort parameters (temperature, relative humidity, CO2) were monitored in all three spaces, the health parameters (total volatile organic compounds—TVOCs; formaldehyde—HCHO; particulate matter—PM; and radon—222Rn) were monitored only in an office setup located right next to a Chemical Analysis and Testing Laboratory. Generally, the registered values of the health parameters fell within the recommended thresholds. However, the thermal comfort parameters were constantly exceeded: over 90% of the working time in the two office spaces and 83.33% in the PV-testing laboratory. Still, the optimal relative humidity values in the monitored spaces contributed to the discomfort reduction in the occupants. Also, CO2 and TVOCs had some exceptions in particular conditions. CO2 values of up to 1500 ppm due to poor ventilation and TVOC levels of up to 1000 ppb related to chemical experiment development were registered. Also, several other peaks were recorded when monitoring HCHO as well as PM. Thus, special attention must be paid to natural ventilation or to the improvement of building characteristics. Also, the time intervals when experiments in the Chemical Analysis and Testing Laboratory are carried out should be communicated to other personnel from the nearest offices. The testing of the monitoring system over a one-week period showed that the proposed solution operated adequately, representing a reliable tool for data acquisition via the Arduino IoT Cloud.

The paper presents the experimental study of the influence of a 50 Hz extremely-low-frequency (ELF) electromagnetic field (EMF) on the growth of microalgae Chlorella vulgaris in a BG11 culture medium. Comparative experimental determinations carried out under reference conditions (microalgae growth without exposure to EMF) and with exposure to a homogeneous 50 Hz EMF of various intensities highlighted the fact that EMF has a major impact on both the growth speed and the nitrogen and phosphorus content of the obtained algal mass. Through spectrophotometry and gravimetric determinations, it was found that the lag time was reduced from approximately 8 h (reference) to approximately 6 h for EMF of 2 V/m, 4.5 h for EMF of 5 V/m, 3.2 h for EMF of 10 V/m, and 2.5 h for EMF of 15 V/m. In the stimulation with 15 V/m EMF, the maximum biomass growth rate was 2.75 times higher than the reference, leading to a 2-fold increase in the rate of exhaustion of nutrients, especially phosphorus, in the culture medium. The specific chemical analyses for N-NO3, total nitrogen TNb, and total phosphorus Pt highlighted that the N-NO3 content of the culture medium decreased by 58 mg/L/day at 15 V/m EMF compared to 43 mg/L for the reference. The Pt content decreased to 90% depletion after approximately 80 h for the reference culture medium, versus only 48 h of growth with exposure to 15 V/m ELF. The TNb content of the algal suspension in BG11 under the influence of 15 V/m EMF for 96 h of growth increased 14 times compared to the reference. This shows that nitrogen metabolization in the dispersed air was significantly stimulated. It was also found that the 50 Hz EMF also influences the nitrogen and phosphorus content of the increased algal mass. The results show the potential of EMF stimulation of Chlorella vulgaris growth, leading to an increased efficiency of algae growth reactors. [ABSTRACT FROM AUTHOR]

IntroductionDigital diagnostic decision support tools promise to accelerate diagnosis and increase health care efficiency in rheumatology. Rheumatic? is an online tool developed by specialists in rheumatology and general medicine together with patients and patient organizations. It calculates a risk score for several rheumatic diseases. We ran a pilot study retrospectively testing Rheumatic? for its ability to differentiate symptoms from existing or emerging immune-mediated rheumatic diseases from other rheumatic and musculoskeletal complaints and disorders in patients visiting rheumatology clinics.Materials and MethodsThe performance of Rheumatic? was tested using in three university rheumatology centers: (A) patients at Risk for RA (Karolinska Institutet, n = 50 individuals with musculoskeletal complaints and anti-citrullinated protein antibody positivity) (B) patients with early joint swelling [dataset B (Erlangen) n = 52]. (C) Patients with early arthritis where the clinician considered it likely to be of auto-immune origin [dataset C (Leiden) n = 73]. In dataset A we tested whether Rheumatic? could predict the development of arthritis. In dataset B and C we tested whether Rheumatic? could predict the development of an immune-mediated rheumatic diseases. We examined the discriminative power of the total score with the Wilcoxon rank test and the area-under-the-receiver-operating-characteristic curve (AUC-ROC). Next, we calculated the test characteristics for these patients passing the first or second expert-based Rheumatic? scoring threshold.ResultsThe total test scores differentiated between: (A) Individuals developing arthritis or not, median 245 vs. 163, P < 0.0001, AUC-ROC = 75.3; (B) patients with an immune-mediated arthritic disease or not median 191 vs. 107, P < 0.0001, AUC-ROC = 79.0; but less patients with an immune-mediated arthritic disease or not amongst those where the clinician already considered an immune mediated disease most likely (median 262 vs. 212, P < 0.0001, AUC-ROC = 53.6). Threshold-1 (advising to visit primary care doctor) was highly specific in dataset A and B (0.72, 0.87, and 0.23, respectively) and sensitive (0.67, 0.61, and 0.67). Threshold-2 (advising to visit rheumatologic care) was very specific in all three centers but not very sensitive: specificity of 1.0, 0.96, and 0.91, sensitivity 0.05, 0.07, 0.14 in dataset A, B, and C, respectively.ConclusionRheumatic? is a web-based patient-centered multilingual diagnostic tool capable of differentiating immune-mediated rheumatic conditions from other musculoskeletal problems. The current scoring system needs to be further optimized.

Objectives Our knowledge about the effect of tocilizumab (TCZ) on the synovium in rheumatoid arthritis (RA) is limited. The aim of this study was to investigate the effect of TCZ on citrullination and on inflammation in the synovial tissue and in the peripheral blood.Methods 15 patients with RA underwent synovial biopsy before and 8 weeks after TCZ initiation. Clinical evaluation was performed at baseline and at 8 weeks. Using immunohistochemistry, we evaluated the expression of CD68, CD3, CD20, osteoprotegerin (OPG) and receptor activator for nuclear factor-κB ligand (RANKL) before and after treatment with TCZ. We also analysed the expression of protein arginine deiminase (PAD)-2 and PAD-4 enzymes in the synovial tissue and protein citrullination patterns with the help of anticitrullinated protein antibody (ACPA) clones 1325:04C03 and 1325:01B09. Serum levels of interleukin-6 (IL-6), IL-8, RANKL, OPG and C-terminal crosslinked telopeptide type II collagen were measured by ELISA. Paired-wise Wilcoxon signed-rank test was used to compare median values before and after treatment.Results Disease activity in patients was reduced from baseline to 8 weeks. Although PAD-2 and PAD-4 expressions remained unchanged after TCZ treatment, the binding of one ACPA clone decreased in the synovial tissue. TCZ did not affect the number of CD68+ macrophages or CD20+ B cells but induced significant decrease in the number of CD3+ T cells. RANKL and OPG expression remained unchanged in the synovial tissue. A significant increase in the levels of IL-6 and RANKL was observed in the serum. This increase was statistically significant in patients who responded to TCZ (achieving Clinical Disease Activity Index low disease activity or remission) but not in non-responders.Conclusions TCZ reduced synovial T-cell counts but not macrophages. A significant increase of serum IL-6 was observed in responders.

The recovery after the unprecedented pandemic crisis that Europe has currently been facing is strengthening the strong dependence between social, economic, and environmental fields, maintaining green investments and innovation at the core of the European strategies. Shifting to clean industries is a challenging mission that a complex network of stakeholders and their different interests must take into account. Within this network, the interplay between environmental and financial performance of a company represents a common point with a growing emphasis on the transparency and the materiality capacity of the disclosed information. This paper uses the Structural Equation Modeling and the Gaussian Graphical Models as graphical analysis approaches and offers a first insight about the interaction between environmental materiality measures and financial performance. A preliminary step of the scientific research consisted of a hand-mapping investigation about materiality conditions. Starting from the Materiality Map developed by the Sustainability Accounting Standards Board (SASB), this paper extends the main concept about materiality and investigates it on three different content ranges, which focus on the general environmental policy of the company, the targets set, and its concrete footprint. The methodology approaches were grounded on a newly compiled dataset provided by the Thomson Reuters database for 194 Economic European Area (EEA) oil and gas companies. The results provide significant evidences for the manifestation of materiality and emphasize the informational content of the individual environmental measures as an important condition for its financial impact. Adding to the environmental-financial performance relationship, our findings have both practical and academic relevance for the economic field and sustainable growth goals.

The blending of nanomaterials into a polymeric matrix is a method known for its ability, under certain circumstances, to lead to an improvement in membrane properties. TiO2 nanoparticles have been used in membrane research for the last 20 years and have continuously shown promise in this field of research. Polysulfone (PSf) membranes were obtained through the phase inversion method, with different TiO2 nanoparticle concentrations (0, 0.1, 0.5, and 1 wt.%) and two types of TiO2 crystalline structure (anatase and rutile), via the addition of commercially available nanopowders. Research showed improvement in all studied properties. In particular, the 0.5 wt.% TiO2 rutile membrane recorded an increase in permeability of 139.7% compared to the control membrane. In terms of overall performance, the best nanocomposite membrane demonstrated a performance index increase of 71.1% compared with the control membrane.

Last years research in polymers registered an increase of interest regarding polymer mixtures aiming to obtain materials with properties of the mixed polymers. In this respect many studies are pointing the mixtures between a thermoset polymer and a thermoplastic polymer. It is known the fact that thermoplastic polymers are much more malleable than the thermoset ones and the goal is to obtain a mixture with the general properties of the thermoset polymer and with a machining ability proper to the thermoset polymer. The vitrimers are this type of polymers and, some of them, can be obtained by mixing polymers form the two categories. This study is about using solutions of two thermoset polymers to modify the basic properties of three epoxy resins. The results show that the presence of PMMA, respectively, PLA inside the epoxy resin matrix determines changes of the mechanical properties of the formed materials. Without analysing the adhesive properties of new materials is hard to decide about their value from the composites applications point of view. [ABSTRACT FROM AUTHOR]

The economic and financial performance, characterized by the two concepts, efficiency and effectiveness, has gained over time a particular importance among the managers of the enterprises in our country and beyond. This depends on the size of the type of management applied within an enterprise, but largely depends on certain external factors specific to the environment in which the entity operates. Regardless of the type of factors we relate to, it is certain that the economic and financial performance changes from one period to the next, and the level of market value of the enterprise changes. We can therefore consider that the economic and financial performance is a factor of influence of the market value, which we want to demonstrate in the present research paper.

Background. A better understanding of the role of endoplasmic reticulum degradation-enhancing alpha-mannosidase – like protein 1 (EDEM1) in endoplasmic reticulum associated degradation (ERAD) may open new therapeutic approaches in autoimmune diseases. Aim. To study ERAD and EDEM1 in the generation and assembly of MHC I and the potential role in the pathophysiology of autoimmune diseases. Materials and methods. HEK293T cell line (human embrionic kidney cells), A375 cell line (amelanotic melanoma cells) and THP-1 cell line (leukemic monocytes used both as undifferentiated and differentiated) underwent transient transfection with EDEM1 and mock transfection with pTriEx. Western blot experiments assessed the total cellular MHC I levels in cell lysates, while expression on the cellular surface was quantified by flow cytometry of fixed cells. Results were analysed using the FACS Calibur and CellQuest Pro dedicated software. Experiments were done twice with duplicate probes for the Western blot assay and triplicate probes were used for flow cytometry. GraphPad Prism was used for data analysis. Results. MHC I plasma membrane routing and expression was similar in HEK293T and A375 both in mock transfected and non-transfected cells. Western blot assay for EDEM1 transfected cells showed bands corresponding to the total MHC I that migrated at 42kDa mass in non-transfected and mock transfected Hek293T, A375 and undifferentiated THP-1 cells. Mock transfected differentiated THP-1 cells showed a reduction of total MHC I. EDEM1 transfected Hek293T, A375 and undifferentiated THP-1 cells displayed higher levels of total MHC I, while differentiated THP-1 cells showed a marked reduction. Flow cytometry assay showed significantly reduced cell surface MHC I levels in Hek293T cell line. We observed a modest reduction of MHC I complexes on the cellular surface in undifferentiated THP-1 EDEM1 transfected cells, while there was no significant change in the A375 EDEM1 transfected cell line, as well as the differentiated THP-1 EDEM1 transfected cells. Conclusion. The impact of ERAD’s EDEM1 in MHC I reduction may have an important role in autoimmune disease, making ERAD an interesting therapeutic target

Some polymers show low thermal properties which can be improved by adding various types of materials. Using nanoparticles, an enhancement of thermal properties can be obtained, even for small contents of additives. The evaluation of thermal properties of polymer composites with graphene can be achieved relying on Differential Scanning Calorimetry tests (DSC). This work presents a few conclusions resulting from DSC tests of the polyester composites with graphene and graphite.

The results of a pilot-scale study on the influence of electric field use for stimulating the active sludge in the biological purification tank of a small capacity wastewater treatment plant (up to 600 m3/day) are presented. Through specific comparative chemical tests (DO, COD, N-NH4, and Pt) it was found that, by applying a sinusoidal electric field of 5 Vrms/m at 49.9 Hz on the active sludge suspension, the overall pollutant denitrification process speed is doubled compared with the reference case when no stimulation is used. Also, under identical operating conditions, the residual pollutant content of the biological treatment tank outlet water is reduced approximately three times for COD and approximately two times for N-NH4 and Pt compared to the reference tank. These findings lead to the conclusion that, by stimulating the active sludge microbial activity of the wastewater treatment plants by a sinusoidal electric field of 5 Vrms/m at 49.9 Hz, the time of the biological purification treatment can be reduced by approx. 50%. This leads to a corresponding decrease in energy consumption, which usually represents more than 30% of a wastewater treatment plant's specific electricity consumption. [ABSTRACT FROM AUTHOR]