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Co-Cr alloys are still used in metal-ceramic technology on the large scale. The purpose of this study was to provide a comparative analysis of the corrosion resistance by the polarization resistance technique of two Co-Cr-based alloys (codified Co-Cr- P and Co-Cr-PW) produced by the same manufacturer, which have a minor variation in chemical composition. Corrosion tests were performed at a temperature of 37 ± 0.5° C in a bath with heating and recirculation, in artificial saliva (SA) Carter Brugirard at pH = 7.58. Both tested alloys showed an increased corrosion resistance when immersed in artificial saliva, proving a good corrosion resistance and therefore a good biocompatibility. The Co-Cr-P test showed superior electrochemical values ​​and, implicitly, higher corrosion resistance.

This paper investigates the effects of ultrasonication on cellulose microparticles in different conditions. FTIR (Fourier transformed infrared spectrometry) and XRD (X-ray diffraction) analyses were used to compare the changes in the cellulose microstructure caused by the following various ultrasonic treatment conditions: time, amplitude of generated ultrasound waves, output power converted into ultrasound, the liquid medium (water and isopropyl alcohol) used for ultrasonication, and the shape of the vessel used for sonication. The cumulative results lead to an increase in the crystalline region directly proportional to the condition of sonication. Also, the total crystallinity index varied from 1.39 (pristine cellulose) to 1.94 for sonication in alcohol to 0.56 for sonication in water. The crystallinity index varied from 67% (cellulose) to 77% for the sample with 15 min of sonication in isopropyl alcohol and 50.4% for the sample with 15 min of sonication in water. [ABSTRACT FROM AUTHOR]

This work describes the synthesis of a polysilane (PSH)–barium titanate (BT) ferroelectric polymer composite that keeps stable in the presence of ultraviolet light (UV). To evaluate the stability in the presence of UV radiation and the mechanism of interaction between the PSH matrix and BT, FTIR measurements were carried out. The UV/VIS absorption measurement reveals that PSH absorbs strongly in the ultraviolet range, while the composite behaves similarly to BT. Although PSH is a semiconductor, the dielectric spectrometry analysis determined that BT is a ferroelectric material due to its high dielectric constant and low dielectric losses. In contrast to the polymer matrix, the composite polymer has a greater dielectric constant and a lower loss permittivity. PSH is a semiconductor, as indicated by its electrical conductivity of 10−5 S/cm; nevertheless, the UV-irradiated polymer has antistatic properties (10−8 S/cm). Irradiated or not, the polymer composite is a semiconductor, with conductivity of 10−6 S/cm, significantly lower than that of PSH. The interaction with electromagnetic radiation indicates electromagnetic shielding behavior for both BT (highest absorption magnitude of −57 dB) and the polymer composite (maximum absorption magnitudes range from 8.4 to −15.2 dB). Based on these research results, the novel composite with specific characteristics may be used in electronic applications in UV-irradiated conditions. [ABSTRACT FROM AUTHOR]

The current study examines the adsorptive potential of a biomaterial resulting from the extraction of cellulose, Sarkanda grass lignin, for the retention of Co(II) from aqueous medium under static conditions. The initial solution pH, initial concentration of Co(II), the adsorbent dose and the contact time between the adsorbent and the adsorbate were the main parameters preliminarily tested in order to accurately establish the optimal experimental conditions. The adsorption capacity of Sarkanda grass lignin was evaluated through surface analyses, the application of the Freundlich and Langmuir models to establish chemical equilibrium conditions, the Lagergren I and Ho-McKay II models for process kinetics, and biological stability analysis of specific indices. The number of germinated seeds or germination energy for the seeds of Triticum aestivum L, Glosa variety, introduced in the contaminated adsorbent and in the filtrates resulting from the phase separation was also evaluated. The results obtained through the aforementioned analysis methods indicate that Sarkanda grass lignin may be a promising solution for the adsorption of Co(II) from wastewater. This is evidenced by the observed adsorption capacity and the time required for the adsorption process. [ABSTRACT FROM AUTHOR]

The evolution from conventional to modern agricultural practices, characterized by Agriculture 4.0 principles such as the application of innovative materials, smart water, and nutrition management, addresses the present-day challenges of food supply. In this context, polymer hydrogels have become a promising material for enhancing agricultural productivity due to their ability to retain and then release water, which can help alleviate the need for frequent irrigation in dryland environments. Furthermore, the controlled release of fertilizers by the hydrogels decreases chemical overdosing risks and the environmental impact associated with the use of agrochemicals. The potential of polymer hydrogels in sustainable agriculture and farming and their impact on soil quality is revealed by their ability to deliver nutritional and protective active ingredients. Thus, the impact of hydrogels on plant growth, development, and yield was discussed. The question of which hydrogels are more suitable for agriculture—natural or synthetic—is debatable, as both have their merits and drawbacks. An analysis of polymer hydrogel life cycles in terms of their initial material has shown the advantage of bio-based hydrogels, such as cellulose, lignin, starch, alginate, chitosan, and their derivatives and hybrids, aligning with sustainable practices and reducing dependence on non-renewable resources. [ABSTRACT FROM AUTHOR]

Biomaterials are an important and integrated part of modern medicine, and their development and improvement are essential. The fundamental requirement of a biomaterial is found to be in its interaction with the surrounding environment, with which it must coexist. The aim of this study was to assess the biological characteristics of hydroxyapatite (HAp)-based coatings doped with Mg and Zn ions obtained by the pulsed galvanostatic electrochemical method on the surface of pure titanium (cp-Ti) functionalized with titanium dioxide nanotubes (NTs TiO2) obtained by anodic oxidation. The obtained results highlighted that the addition of Zn or Mg into the HAp structure enhances the in vitro response of the cp-Ti surface functionalized with NT TiO2. The contact angle and surface free energy showed that all the developed surfaces have a hydrophilic character in comparison with the cp-Ti surface. The HAp-based coatings doped with Zn registered superior values than the ones with Mg, in terms of biomineralization, electrochemical behavior, and cell interaction. Overall, it can be said that the addition of Mg or Zn can enhance the in vitro behavior of the HAp-based coatings in accordance with clinical requirements. Antibacterial tests showed that the proposed HAp-Mg coatings had no efficiency against Escherichia coli, while the HAp-Zn coatings registered the highest antibacterial efficiency. [ABSTRACT FROM AUTHOR]

The study aims to inform and increase awareness not only about the impact of the maritime area on the economy and its potential benefits, but also about the transposition of European policies and strategies at national level, which often leads to legislative challenges – usually in terms of internal administrative responsibility and liability – that are not missing from the maritime spatial planning process either. In order to avoid possible penalties that could be applied following the triggering of the infringement procedure, Romania adopted at the end of 2023 the “Maritime Spatial Planning”. The actual plan defines new ways of jointly exercising competences, a novelty apart from the existing ones, mainly for central public authorities. The development and implementation of the “Maritime Spatial Planning” are based on leveraging the existing data and the collaboration of stakeholders – including central and local public authorities and institutions, business, academia, civil society and the general public – without introducing new burdens or special regulations. Considering the extent of the “Maritime Spatial Planning Plan” and the fact that it mainly concerns the exclusive public property of the Romanian State, it is necessary, more than ever, to pay particular attention to the application of the principle recognised as professional “responsibility and liability” of public administration officials. [ABSTRACT FROM AUTHOR]

University dropout has become a worrying reality for the education system in general, but also for Romania in particular, which ranks first in Europe. Thus, the worrying phenomenon of early university leaving is a phenomenon that has complex causes and therefore requires a variety of ways to combat it. These include the development of a supportive extra-curricular environment and individualized teaching practices focused on student-centered learning to support their potential. The aim of the research undertaken in this paper is to demonstrate the contribution of learning support activities in a formal and non-formal environment to the progress of first year of "Iasi University of Life Sciences" (IULS) students in the Faculties of Agriculture and Horticulture in reducing dropout. The qualitative research methodology was carried out through a review of the literature on university dropout, predominantly early. The case study, as a quantitative research method, is composed of a questionnaire containing 13 questions applied to first year students at IULS Iasi. The resulting data were processed and analyzed by statistical methods, and after interpreting the results we formed an overview of the problem of the causes of early university dropout of first year students and thus could apply personalized support measures. As a result of the steps taken in this respect, adaptability to the university environment increased and early university leaving was reduced, which provided us with a working model. This work has an innovative character in terms of the educational support measures provided to first year students at IULS Iasi, which constitute a model of good practice for increasing the adaptability of first year students to the university environment and for reducing early dropout. These extracurricular activities, carried out in a formal and especially non-formal friendly environment in a modern way, must be continued and adapted to the students' needs, but taking into account the skills they need to acquire in order to finally integrate into the changing labour market. [ABSTRACT FROM AUTHOR]

Heavy metals are pollutants that pose a risk to living systems due to their high toxicity and ability to accumulate and contaminate. This study proposes an alternative approach to the static adsorption of Ni(II) from aqueous media using Sarkanda grass lignin crystals, the non-cellulosic aromatic component of biomass, as an adsorbent substrate. To determine the best experimental conditions, we conducted tests on several parameters, including the initial and adsorbent solution pH, the concentration of Ni(II) in the aqueous solution, the amount of adsorbent used, and the contact time at the interface. The lignin's adsorption capacity was evaluated using the Freundlich and Langmuir models to establish equilibrium conditions. The Lagergren I and Ho–McKay II kinetic models were used to determine the adsorption mechanism based on surface analyses and biological parameters such as the number of germinated seeds, energy, and germination capacity in wheat caryopses (variety Glosa) incorporated in the contaminated lignin and in the filtrates resulting from phase separation. The results suggest that Sarkanda grass lignin is effective in adsorbing Ni(II) from aqueous media, particularly in terms of adsorbent/adsorbate dosage and interfacial contact time. [ABSTRACT FROM AUTHOR]

In this article I explore how certain pedagogic practices construct students' ability as visible. The concept of ability is viewed as constructed, put into place by specific educational practices, rather than a fixed traitof the students. Conducted in two primary classrooms, this study employs observational methods complemented by audio-video recording. Through the analysis of the recordings and transcripts, I identify and thematize several pedagogical practices, used to organize learning activities. The analysis is framed by Basil Bernstein's concepts of visible pedagogy and framing, complemented by Rosenholtz and Simpson's (1984) view of ability as a socially constructed phenomenon. The findings are organized around two main themes that align with Bernstein's concepts of visible pedagogy: (1) Practices that make visible the means for ability development, and (2) Practices that make visible the rhythm of ability. The study aims to contribute to our understanding of how ability, a central concept in education, can be viewd as socially constructed by pedagogical practices, understood as an alternative to the developmentalist view that sees the same concept as fix, normally disperesed and liniearly developed. [ABSTRACT FROM AUTHOR]

The role of university education in providing access to the labour market (employment) is reflected in increased employment opportunities for the educated population. The relationship between the unemployment rate and educational attainment is evident: the unemployment rate decreases as one moves from lower to higher levels of education. It can be seen that the unemployment rate, in terms of its size and dynamics, is inversely proportional to the level of education: it falls as the level of education rises, and vice versa. The aim of the research in this paper is to respond to the need to teach students with practical solutions for getting the skills needed to be easily employable in the labour market after graduation. The paper used a quantitative (questionnaire) and a qualitative (bibliometric) analysis. The data studied through the research shows the need for final-year students to receive additional practical skills training for employability. Entrepreneurship education, in addition to the university curriculum, can provide them with a viable alternative to increase their chances of integrating into the 21st century labour market. The innovative character of the work derives from the concrete practical activities that supported the optional entrepreneurial training of IULS students from Iasi. We can affirm, following the study undertaken, that the development of such additional and adapted educational activities increases young graduates' practical skills needed on the labour market. The access to non-reimbursable European funds, which offer additional educational opportunities to students, must be continued in order to produce the major economic effects expected by the whole Romanian society, with the aim of reducing youth unemployment. [ABSTRACT FROM AUTHOR]

A2 milk is characterized by a difference in the amino acid at position 67 of the β-casein polypeptide chain, which releases much smaller amounts of bioactive opioid peptide β-casomorphin - 7 upon digestion. Milk consumption may lead to discomfort due to the presence of A1 beta-casein protein. A2 milk is the preferable alternative for people with mild lactose intolerance or lactose sensitivity because it does not include A1 protein, which is thought to be kinder to the digestive system. The need for healthy and minimally processed dairy products, the growing awareness of dairyrelated sensitivities, as well as the growing interest in organic and natural food options are some of the major reasons driving the expansion of the A2 milk market. The purpose of this review is to present the advantages and challenges of using A2 milk in the manufacturing of dairy products. [ABSTRACT FROM AUTHOR]

In this paper, the synthesis and characterization of two polycaprolactone-polydimethylsiloxane (PDMS-CL) copolymers with biodegradable properties are reported. A comparative study was carried out using an aminopropyl-terminated polydimethylsiloxane macro-initiator (APDMS) with two different molecular weights. The copolymers (PDMS-CL-1 and PDMS-CL-2) were obtained by ring-opening polymerization of ɛ-caprolactone using APDMS as initiators and stannous 2-ethylhexanoate as a catalyst. The copolymer's structures were confirmed by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H-NMR) spectra, and energy dispersion spectroscopy (EDX). Surface morphology was investigated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The hydrophobic properties of the copolymers were demonstrated by the water contact angle and water vapor sorption capacity. Additionally, biological tests were conducted on San Marzano type tomato plants (Lypercosium esculentum) to assess the synthesized copolymers' susceptibility to the environment in terms of biological stability and metabolic activity. The biodegradation of PDMS-CL-1 and PDMS-CL-2 copolymers does not have a dangerous effect on the metabolic activity of plants, which makes it a convenient product in interaction with the environment. [ABSTRACT FROM AUTHOR]

Mycotoxins and heavy metals are contaminants that affect harvests, animal and human health and produce economic losses. The article aims to present the occurrence of mycotoxin deoxynivalenol and heavy metals (lead, copper, arsenic, chromium, nickel, zinc, manganese, and cadmium) contamination in common wheat in Romania in the extremely dry year 2015. The samples taken from localities characterized by deoxynivalenol contamination in 2012 - 2014, were analyzed through enzyme-linked immunosorbent assay (ELISA) and inductively coupled plasma mass spectrometry (ICP-MS) methods and the gained data were evaluated by SPSS. Wheat exceeded the maximum limits for deoxynivalenol and lead in the northwestern, western and central regions (46-48 °N, 21-25 °E; acidic soils; humid to subhumid climate); the heavy metals concentrations had the order Mn > Zn > Cu > Ni > Cr > Pb > As > Cd. Deoxynivalenol was only correlated with copper, but there were significant and very significant correlations between heavy metals with toxic and carcinogenic potential (lead, arsenic, chromium, nickel, and copper). Contamination with deoxynivalenol and heavy metals in common wheat was low in the extremely dry year 2015, but it was high in soils, air, waters and plants in the extremely rainy years as: 2010, 2013, 2014 and 2016. Gained data are useful because they showed that extreme weather events and climate change affect heavy metal pollution in the environment and also Fusarium spp. and deoxynivalenol contamination in cereals, therefore agro-food safety and security. [ABSTRACT FROM AUTHOR]

Introduction: Total body irradiation (TBI) practices vary considerably amongst centres, and the risk of treatment related toxicities remains unclear. We report lung doses for 142 TBI patients who underwent either standing TBI with lung shield blocks or lying TBI without blocks. Methods: Lung doses were calculated for 142 TBI patients treated between June 2016 and June 2021. Patients were planned using Eclipse (Varian Medical Systems) using AAA_15.6.06 for photon dose calculations and EMC_15.6.06 for electron chest wall boost fields. Mean and maximum lung doses were calculated. Results: Thirty‐seven patients (26.2%) were treated standing using lung shielding blocks with 104 (73.8%) treated lying down. Lowest relative mean lung doses were achieved using lung shielding blocks in standing TBI, reducing the mean lung doses to 75.2% of prescription (9.9 Gy), ±4.1% (range 68.6–84.1%) for a prescribed dose of 13.2 Gy in 11 fractions, including contributions from electron chest wall boost fields, compared to 12 Gy in 6 fraction lying TBI receiving 101.6% mean lung dose (12.2 Gy) ±2.4% (range 95.2–109.5%) (P ≪ 0.05). Patients treated lying down with 2 Gy single fraction received the highest relative mean lung dose on average, with 108.4% (2.2 Gy) ±2.6% of prescription (range 103.2–114.4%). Conclusion: Lung doses have been reported for 142 TBI patients using the lying and standing techniques described herein. Lung shielding blocks significantly reduced mean lung doses despite the addition of electron boost fields to the chest wall. [ABSTRACT FROM AUTHOR]

Cardboard packaging is widely used in the food industry, especially as secondary or tertiary packaging, or as transport packaging. In most cases, these packs may contain certain chemical contaminants that can be accidentally transferred to packaged foods. These contaminants include Bisphenol A (BPA) and Formaldehyde, which can cause significant adverse effects, especially to vulnerable persons. For this reason, the purpose of this study was to analyze by a UV - VIS spectrophotometric method the content of BPA and Formaldehyde from 17 corrugated board samples from Romanian producers. BPA concentrations varied between 0.044 mg/dm2 and 0.090 mg/dm2, while Formaldehyde concentrations were lower than 0.048 mg/dm2. The results were compared with the legislation in force to establish their compliance for contact with food.

With the development of industry, large amounts of heavy metals are eliminated into the environment, which leads to contamination of important water resources, such as ground waters, surface waters, and lake waters. They can also get into drinking water and by ingestion, pollutants can accumulate in the human body where it manifests toxic effects on various systems and organs. In order to minimize the contamination of water resources and wastewater, the removal of heavy metals is being studied more and more through the use of various processes, such as adsorption, membrane filtration, ion exchange or coagulation. The aim of this review paper is a state-of -the-art discussion about the effective applications of different removal processes and sorbent materials for heavy metals removal from water resources. For conducting the study were consulted more than 50 literature sources from the most important electronic databases: Web of Science and SCOPUS. Several platforms such as Science Direct, Springer Link, CAB Abstracts and Taylor and Francis were also consulted. Processes we are talking about include the use of adsorbent materials, such as activated carbon, nanotubes, bio-sorbents and bio-chars, or various filtration processes, that include ultrafiltration, microfiltration, nanofiltration or reverse osmosis. However, of all the adsorbent materials, bio-sorbents have gained considerable attention for applications in water treatment, due to their cost-effectiveness, acceptable performance and high removal capacity. Their most important aspect is eco-friendly character, as most come from agricultural waste (peanuts, rice, lemon peel, cocoa shells, and coffee residues), soil and mineral deposits (bentonite, kaolin, and zeolite) or aquatic and terrestrial biomass (lignin, seaweed, algae). Bio-sorbents may be subjected to processes like electrostatic interaction, precipitation, chelation, complexation, to enhance their adsorption capacity. The research studies demonstrated that the removal rate is influenced by some parameters, like the pH of the aqueous media, the adsorbent dose, concentration of the metal, time of contact, temperature, and mixing or agitation speed. As a conclusion, the removal processes show good adsorption capacities for heavy metals, but further research are needed for successful applications of these methods for removal of chemical pollutants from drinking water. [ABSTRACT FROM AUTHOR]

The use of seasoning and aromatic plants plays an important role in the food industry due to bioactive compounds which improve the taste of food and can influence digestion and metabolism. Contamination of these plants with heavy metals, mycotoxins, polycyclic carbohydrate residues and pesticides, may occur during both cultivation and conditioning. The aim of this review was the investigation of the levels of heavy metals in some aromatic plants and seasonings from different countries. The content of these heavy metals and trace elements was tested through different methods. By comparing the data from more than 50 papers available on WoS, Springer, SCOPUS, CAB Abstracts, the results showed that the content of heavy metals in some spices exceeds the permitted limit and poses a risk to human health. In case of trace metals, these contribute to the proper functioning of the body, but if exceeding the tolerable daily intake, they become toxic and pose a risk to human health. After ingestion, heavy metals can bioaccumulate into the body and produce adverse effects on human health, as neurotoxicity, disorders of cardiovascular, gastrointestinal, renal and reproductive system, hepatotoxicity, immunotoxicity, but also carcinogenesis through generation of free radicals. Spices and aromatic plants may contain high amounts of heavy metals and trace elements, therefore their accumulation in the human body may pose a risk to human health. [ABSTRACT FROM AUTHOR]