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Sewage sludge valorization in agricultural fields is in many countries a circular economy strategy to handle the disposal issues of this complex residue. Many countries regulate the content of heavy metals and other agrochemical parameters in sewage sludge, establishing threshold limits for its application in agricultural fields. This requires the employment of robust, time-saving, and cost-effective analytical tools suitable for multielemental analysis at trace levels. Inductively coupled plasma optical emission spectrometry (ICP-OES) is a powerful instrumental technique with proven success in this field. In this laboratory experience, students perform a multielemental analysis of sewage sludge samples, by sample acidic digestion in a closed microwave system followed by ICP-OES analysis. Validation of the analytical method is also proposed, evaluating the linear response of an external calibration with internal standardization and using a certified reference material for evaluation of recovery and precision. The method is to be applied to a real sewage sludge sample to assess its nutrient content and to compare levels of heavy metals with enforced regulations. This work was successfully carried out in an analytical chemistry class with undergraduate students of chemical, environmental, and bioengineering bachelor degree courses. Most students reached the proposed learning goals, obtaining good or very good classifications in all evaluated parameters in the assessments of laboratory performance and final group reports.

This work aims to describe the socio-technical network of a Chemistry laboratory in the school "Professora Maria do Rosário Castaldi", a State Center for Professional Education in the city of Londrina, Brazil, taking the translation theories proposed by Bruno Latour as motivation. The observation data were either recorded in audio or written in a diary, following the laboratory studies perspectives, particularly those of the Actor-Network Theory. According to these perspectives, the laboratory can be understood as an imbricate network composed of several elements, instances, interests, partnerships, procedures and knowledge, all of which produced by human and non-human entities that constitute the objects and meanings known to us as sciences or scientific practices. In addition, the concept of translation--a key concept of this theoretical body--helped to understand the heterogeneous set of elements mobilized by its actors with the aim of making the laboratory a recognized and consolidated organization. The observation and description of the material indicate how the network makes the analyzed laboratory something that is both completely dependent on and producer of the network in which it operates. Namely, the manner such process of materialization of the laboratory is dependent on a number of associations, negotiations, strategies, and alignments performed by human and non-human actors, linking the largest number of elements in order to make the construction of this space possible. The discussion allowed one to conclude that its permanence and success are not guaranteed, given that the whole process of collective action is always about to break or fall apart at any point.

A laboratory application with a strong component in analytical chemistry was designed for undergraduate students, in order to introduce a current problem in the environmental science field, the water contamination by antibiotics. Therefore, a simple and rapid method based on direct injection and high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed and optimized for the determination of amoxicillin in river water. Students learned the main optimization steps for the improvement of the LC-MS/MS methodology and the correct procedure to validate an analytical method (draw a calibration curve, determine detection and quantification limits, precision, and accuracy). This laboratory experiment was successfully applied by students and enables the analysis of a large number of samples in a short period of time because of the short run time (3 min).

This paper describes a mini-project developed with 10th grade Portuguese students where, by using an experimental activity involving the use of natural dyes to colour wool, students acquired a better understanding of the concepts and relationship between the colour, the electromagnetic spectrum, and chemical bonding. As demonstrated by the results of a laboratory activity interest survey, the interdisciplinary nature of the mini-project contributed to raise student awareness to the existing relationship between science, culture and daily life, promoting their overall interest in scientific topics.

Abstract Bottom-up engineering is a very attractive field. However, the periodic organization of molecules on a solid substrate is challenging, particularly in the selection of the appropriate characterization technique which is suitable for both large area and accurate analysis at the nanoscale. Here, this study demonstrates the unambiguous identification of complex molecular layers by infrared absorption microscopy at the nanometric scale. This technique allowed for the direct observation of the presence of isolated polyoxometalate-based nanoclusters dispersed all over a substrate.

For nearly 30 years, the International Network to study Deposition and Atmospheric chemistry in AFrica (INDAAF) programme has measured surface ozone from 14 sites in Africa representative of the main African ecosystems: dry savannas (Banizoumbou, Niger; Katibougou and Agoufou, Mali; Bambey and Dahra, Senegal), wet savannas (Lamto, Côte d'Ivoire; Djougou, Benin), forests (Zoétélé, Cameroon; Bomassa, Republic of the Congo) and agricultural–semi-arid savannas (Mbita, Kenya; Louis Trichardt, Amersfoort, Skukuza and Cape Point, South Africa). The data are collected with passive samplers and archived as monthly averages; quality assurance is maintained by INDAAF's calibration and intercomparison protocols with other programmes employing the same systems. This analysis reports on correlations of INDAAF ozone time series (1995–2020) with local meteorological parameters and with ozone precursors, biogenic volatile organic compounds (BVOCs) and nitrogen oxides (NOx), derived from standard global databases. Mean annual averages of surface ozone range from 3.9 ± 1.1 ppb (Bomassa) to 30.8 ± 8.0 ppb (Louis Trichardt), reflecting a general positive gradient from west central Africa to South Africa. At the decade scale, from 2000 to 2020, the Katibougou and Banizoumbou sites (dry savanna) experienced a significant decrease in ozone of around −2.4 and −0.8 ppb per decade, respectively. These decreasing trends are consistent with those observed for nitrogen dioxide (NO2) and BVOCs. An increasing trend is observed in Zoétélé (2001–2020), estimated at +0.7 ppb per decade, and at Skukuza (2000–2015; +3.4 ppb per decade). The increasing trends are consistent with increasing biogenic emissions at Zoétélé and NO2 levels at Skukuza. Very few surface O3 measurements exist in Africa, and the long-term results presented in this study are the most extensive for the ecosystems studied. The importance of maintaining long-term observations like INDAAF cannot be overstated. The data can be used to assess ozone impacts on African crops. For the Tropospheric Ozone Assessment Report Phase II (TOAR II), they provide invaluable constraints for models of chemical and climate processes in the atmosphere.

This paper presents a history of chemistry case study focusing on selected aspects of the work of American engineer Thomas Midgley, Jr. (1889-1944): the development of tetraethyl lead as an antiknock gasoline additive and of chlorofluorocarbons (CFCs) as fluids for refrigeration devices. One general aim of this case study is to display the complex nature of science, including the relation of science to technological and social issues, the nonlinear and noncumulative nature of its development, and the contribution of people with different backgrounds to the construction of scientific knowledge. Moreover, this work focuses on promoting reflections about two main themes: the periodic table as a tool for chemists' work and the ethical issues related to chemical risks. This case study may help chemistry teachers to enlarge and enrich their views on chemistry as a science and as a profession and to discuss such issues with students.

The Brazil nut is a highly valuable species in the Amazon, both for its economic value and for its nutritional profile. To preserve the nutritional quality of the oil extracted from these nuts, it is important to use appropriate extraction techniques. Among the options available is ultrasound-assisted extraction, which improves solvent penetration and facilitates mass transfer in ruptured cells, making it an efficient approach that preserves the quality of the final product. The aim of this study was to evaluate the changes in the physicochemical and thermal characteristics of Brazil nut oil after ultrasound treatment. Quality parameters were considered, such as acidity and saponification indices, as well as thermal-oxidative properties such as density, viscosity and thermogravimetry. The results indicated that this technique did not significantly alter the properties of the oil and, according to the thermophysical analyses, the Brazil nut oil obtained by ultrasound-assisted extraction showed characteristics similar to other vegetable oils, such as a density of 887 kg.m-3 at 20 oC and a viscosity of 32.5 mPa.s at 25 oC. The proposed method proved to be a practical, fast and economical alternative for extracting Brazil nut oil, maintaining its quality and guaranteeing consumer safety. These characteristics are essential for its application in food products such as chocolates, ice cream and bakery items, as well as its potential use in the cosmetics industry.

The interaction between light and chemical reactions in photochemistry is essential for triggering previously inaccessible transformations and optimizing known reactions. Building efficient photoreactors faces challenges like temperature control, proper agitation, and safe light irradiation. The initiative to develop an affordable LED (light-emitting diode) photoreactor demonstrates the feasibility of adjustable versatile systems for different wavelengths, allowing reactions to be carried out on a microscale and a preparative scale. Furthermore, the importance of customized photoreactors is emphasized as they provide temperature stabilization, precise light exposure control, and the ability to adapt to different light sources, maximizing the efficiency and selectivity of photochemical reactions. This work presents the development and application of a low-cost, functional, adaptable, and efficient photoreactor. Practical evaluation conducted in the arylation of furan C-H showed adequate temperature control, good light irradiation intensity, appropriate wavelength of applied light, agitation for mixture homogenization, and reaction scale-up. The experimentally observed factors contribute to validating the reactor’s efficiency.

FROM SAMPLING TO PURIFICATION: METHODOLOGIES AND TECHNIQUES FOR EVALUATION OF SILOXANES IN BIOGAS. Biogas has emerged as an important source of clean and renewable energy, with its energy viability dependent on purity grade. Primarily composed by methane and carbon dioxide, biogas can also contain nitrogen, water vapor, oxygen, hydrogen sulfide, ammonia, hydrocarbons and siloxanes. Regarding methane, all other components are considered contaminants, with volatile methylsiloxanes (VMSs) being the major challenge in terms of control and removal. VMSs are commonly found in personal care products and industrial applications, and their presence is highly detrimental to biogas energy generation equipment by forming silica deposits that cause fouling and damage, reducing operational efficiency and system longevity. In this context, three topics are crucial: (i) sampling techniques (bags, gas cylinders, canisters, adsorbent tubes, and impingers); (ii) detection and quantification methods for VMSs, highlighting gas chromatography coupled with mass spectrometry; and (iii) biogas purification/removal strategies (adsorption, absorption, refrigeration/condensation, biological degradation, and membrane separation). This review explores the methodologies involved in these topics, presenting literature research approaches and their effectiveness regarding siloxanes, contributing to biogas applications.

EVALUATION AND COMPARISON OF COLOIDAL SYSTEMS OF UHT MILK MARKETED IN THE SOUTH AND SOUTHEAST REGIONS OF BRAZIL. Ultra high temperature (UHT) milk has great relevance in the Brazilian dairy market. Thermal processing, physical-chemical and compositional properties have relevant impact on the quality of milk processed via UHT. The emergence of new categories of this product makes the production scenario even more challenging. The aim of this study was to investigate UHT milk and the effect of food additives on it, from a colloidal perspective, in the main consumer regions. The colloidal systems of samples with or without addition of stabilizers and with or without addition of tricalcium phosphate were evaluated based on analyses of ionic calcium concentration, pH, sedimentation, HCT (heat coagulation time), ethanol stability, particle size (D90) and zeta potential. The results indicated a relevant colloidal stability for this type of matrix, in addition to an efficient industrial homogenization process. The samples that received stabilizers addition showed lower ionic calcium, higher HCT and greater ethanol stability. There was no significant difference in sediment mass and pH. The samples that received Ca3(PO4)2 addition showed higher sedimentation and lower stability to ethanol. There were no significant differences regarding ionic calcium, pH and HCT.

Given the challenges associated with understanding electrochemistry content by engaging in prediction, observation, and explanation, laboratory activities can foster active participation and critical thinking, enabling individuals to proactively confront and revise their understanding. Since pre-service teachers should gain firsthand experience with predict-observe-based on a predict-observe-explain strategy, we propose a laboratory activity presented as a “mystery box” related to concentration cells coupled with an Arduino-based electronic data measurement system to identify how pre-service chemistry teachers move from observations to inferences in a qualitative research. Data was collected by written records and oral explanations during the practical interactions. Results suggest that the proposed laboratory activity allows pre-service chemistry teachers to access data and correct inferences related to electrochemistry content, promoting critical thinking. Data also showed a connection between the macroscopic and symbolic domains, and pre-service teachers recognized concepts associated with the activity, such as solution conductivity and the potential difference in chemical reactions, interpreting the system with prior knowledge, like electron flow direction and concentration cell components. However, additional strategies are needed for detailed and consistent observation and inference recording, enhancing the potential of such activities in favoring electrochemistry education in high schools.

Melipona quadrifasciata is a stingless bee native to Brazil, known for producing a geopropolis with complex composition and diverse biological activity. The study aimed to identify the terpenes present in geopropolis collected from Melipona quadrifasciata colonies located in the state of Rio Grande do Sul, Brazil, to establish a geographic profile that enhances the understanding of the phytochemical composition of geopropolis from southern Brazil. The volatile fraction was analyzed by headspace-gas chromatography/mass spectrometry (HS-GC/MS) and identified fifty-six (56) mono- and sesquiterpenes, with particularly high concentrations of α- and β-pinene. These two compounds were present in all geopropolis samples at concentrations exceeding 50% and were identified as geographical markers of M. quadrifasciata geopropolis from the state of Rio Grande do Sul. Additionally, gas chromatography-mass spectrometry (GC-MS) analysis of the hexane fraction obtained via cold extraction under ultrasound revealed the presence of abietane diterpenes and pentacyclic triterpenes, particularly amyrins, with α-amyrin presented in all geopropolis samples.

Diabetes mellitus is a world-wide health concern with several millions affected in all ages. Computer-aided drug design (CADD) is a powerful tool that has revolutionized the process of discovering and developing new drugs. It provides innovative methods that can speed up drug discovery and lower costs thereby results to increase enthusiasm at developing instinctive antidiabetic agents as alternatives for managing diabetes. Nymphaea lotus, a plant with medicinal properties known for its anti-diabetic effects, contains bioactive components like N-acetyl glucosamine. An in silico study was conducted to investigate its potential in targeting proteins related to diabetes. Molecular docking studies, toxicity prediction, examination of drug depiction, and Molecular Dynamics Simulation (MDs) of the ligands with the identified receptor target were conducted using the Schrödinger platform. The receptor-ligand complex of Nymphaea lotus was compared with known inhibitors. Molecular dynamics simulation, principal component analysis, and free energy landscape analysis showed that the binding affinity of the Nymphaea lotus complex was higher than that of reference ligands. This suggests that Nymphaea lotus and its bioactive compounds have promising medicinal value for managing type 2 diabetes, warranting further research into their therapeutic potential.

Assuming that textbooks give literary expression to cultural and ideological values of a nation or group, we propose the analysis of chemistry textbooks used in Brazilian universities throughout the twentieth century. We analyzed iconographic and textual aspects of 31 textbooks which had significant diffusion in the context of Brazilian universities at that period. As a result of the iconographic analysis, nine categories of images were proposed: (1) laboratory and experimentation, (2) industry and production, (3) graphs and diagrams, (4) illustrations related to daily life, (5) models, (6) illustrations related to the history of science, (7) pictures or diagrams of animal, vegetable or mineral samples, (8) analogies and (9) concepts of physics. The distribution of images among the categories showed a different emphasis in the presentation of chemical content due to a commitment to different conceptions of chemistry over the period. So, we started with chemistry as an experimental science in the early twentieth century, with an emphasis change to the principles of chemistry from the 1950s, culminating in a chemistry of undeniable technological influence. Results showed that reflections not only on the history of science, but on the history of science education, may be useful for the improvement of science education.

The inclusion of the history of science in science curricula--and specially, in the curricula of science teachers--is a trend that has been followed in several countries. The reasons advanced for the study of the history of science are manifold. This paper presents a case study in the history of chemistry, on the early developments of John Dalton's atomic theory. Based on the case study, several questions that are worth discussing in educational contexts are pointed out. It is argued that the kind of history of science that was made in the first decades of the twentieth century (encyclopaedic, continuist, essentially anachronistic) is not appropriate for the development of the competences that are expected from the students of sciences in the present. Science teaching for current days will benefit from the approach that may be termed the "new historiography of science".

The excerpts from The Periodic Table book written by Primo Levi is discussed related to chemical concepts. The use of a literary text as a starting point of discussions of chemical concepts has allowed the integration of various topics covered in separate courses of the undergraduate program in chemistry.

This study presents a simple, low-cost, and efficient route to obtain zinc oxide by adopting the thermal decomposition method of zinc acetate at 300 (Gr@ZnO_300), 400 (Gr@ZnO_400), 500 (Gr@ZnO_500), and 600 °C (Gr@ZnO_600) for 1 h. The diffraction patterns collected for the samples indicated the majority formation of the hexagonal phase (P63mc) for zinc oxide and residual amounts for graphitic carbon, which has a hexagonal structure of space group P63/mmc. The images collected by scanning electron microscopy (SEM) revealed the formation of sub-microcrystals with elongated rod-shaped morphology, with dimensions between 0.223 and 1.09 μm. The optical and colourimetric properties of the obtained materials indicate the presence of graphitic carbon in the samples, corroborating the analysis by XRD and Raman spectroscopy, with an optical bandgap close to 3.21 eV, and energies of the valence (EVB) and conduction (ECB) bands of 2.89 eV and −0.31 eV, respectively. The photocatalytic performance at 20 min of exposure time under UV light of all prepared samples in the decolourisation of rhodamine B (RhB) dye solutions follows the order Gr@ZnO_300 (95.6%) > Gr@ZnO_600 (92.8%) > Gr@ZnO_400 (84.0%) > Gr@ZnO_500 (78.1%), where the photocatalytic performance of Gr@ZnO_300 sample was 16.5 times more effective than the photolysis test. Moreover, the results confirmed that the best performance was archived at pH = 10, and the holes (h+) and superoxide (O2•−) radicals are the main species involved in the discolouration of RhB dye molecules in an aqueous medium. Finally, the reusability experiment shows high stability of the Gr@ZnO_300 sample as a solid photocatalyst and cycling capability, which obtained total discolouration of RhB of a solution under five cycling experiments of 60 min of exposure to UV light at room temperature.

In this study, we utilised ground-based in situ measurements of the aerosol chemical composition and particle size distribution, along with meteorological data from the European Centre for Medium-Range Weather Forecasts (ECMWF), to predict vertical profiles of aerosol optical properties, including the aerosol scattering coefficient, backscatter coefficient, extinction coefficient, and lidar ratio. The predicted ambient profiles were compared to retrievals by a multi-wavelength Raman lidar during the Ruisdael Land–Atmosphere Interactions Intensive Trace-gas and Aerosol (RITA) campaign in the Netherlands in 2021 for 26 time periods of approximately 1 h each. Predicted and retrieved extensive aerosol properties (scattering, backscatter, and extinction coefficient) were comparable only approximately 35 % of the time, mostly under the condition of well-mixed boundary layers. In this case, ground-based measurements can provide a way to extend extinction profiles to lower altitudes, where they cannot be retrieved, and to verify the lidar-measured profiles. Accurate representation of hygroscopic growth is required for adjusting the dry size distribution to ambient size distribution, and the estimated relative humidity profile may have a substantial influence on the shape of the calculated profiles. On the other hand, the lidar ratio profiles predicted by ground-based data also compared reasonably well to the retrieved lidar profiles (starting at 800 m) for conditions where the predicted and retrieved backscatter profiles differed considerably. The difference in the predicted and retrieved lidar ratio is usually less than ±30 %. Our study thus shows that, for well-mixed boundary layers, a representative lidar ratio can be estimated from ground-based in situ measurements of chemical composition and dry size distribution. This approach offers a method of providing lidar ratios calculated from independent in situ measurements for simple backscatter lidars or at times when Raman lidar profiles cannot be measured (e.g. during the daytime). It only uses data that are routinely available at aerosol measurement stations and is therefore not only useful for further validating lidar measurements but also for bridging the gap between in situ measurements and lidar remote sensing.

This study presents the first application of combined ultrasound (US) and microwave (MW) techniques for the efficient extraction of lupin protein isolates (LPI) from Irish-grown narrow-leaved lupin grain, variety ‘PRIMADONNA’. This variety was chosen due to its suitability for growth in the Irish temperate climate, which may influence protein extraction characteristics. By employing these emerging techniques, this research demonstrates a potential approach for improving protein recovery rates as well as enhancing the structural and functional properties of LPI. US and MW treatments significantly outperformed conventional extraction (CE), with combined US and MW treatments showing synergistic effects that significantly enhanced extraction yield and protein recovery rates of LPI (P

In this study, we explored traditional methods commonly found in the literature to analyze how surfactants and polymers interact during the synthesis of polyesters in emulsion systems. The study justifies its focus on micellar catalysis by exploring its effectiveness and suggesting methods for enhancing the synergy among surfactants, reactants, and catalys. We looked at factors like surface tension, critical micelle concentration, micelle shapes, aggregation numbers, and interfacial phenomena in the process of macromolecular packing in emulsion polycondensation. A surfactant-water system consisting of dodecylbenzenesulfonic acid and sodium dodecyl sulfate was employed. Polyesters were prepared from glycerol, ethylene glycol, diethylene glycol, and dicarboxylic acids in a surfactant-water system under mild conditions ranging from 70-150 °C. FTIR and 1H NMR confirmed the esterification. Differential scanning calorimetry indicated no crystallinity and a glass transition temperature range of –53 to –46 °C, typical of soft matter. The resulting polymers had molecular weights ranging from 1180 – 6800 g/mol. We found that these polymer aggregate shapes are able to respond by changing their sizes, both in bulk and at the air-solution interface, when the concentration of surfactant is increased above the critical micelle concentration. The results showed narrow spherical and ellipsoidal polymer aggregates, and the system was found to be suitable for green chemistry applications.

Abstract A key strategy for minimizing our reliance on precious metals is to increase the fraction of surface atoms and improve the metal-support interface. In this work, we employ a solvent/ligand/counterion-free method to deposit copper in the atomic form directly onto a nanotextured surface of graphitized carbon nanofibers (GNFs). Our results demonstrate that under these conditions, copper atoms coalesce into nanoparticles securely anchored to the graphitic step edges, limiting their growth to 2–5 nm. The resultant hybrid Cu/GNF material displays high selectivity in the CO2 reduction reaction (CO2RR) for formate production with a faradaic efficiency of ~94% at -0.38 V vs RHE and a high turnover frequency of 2.78 × 106 h-1. The Cu nanoparticles adhered to the graphitic step edges significantly enhance electron transfer to CO2. Long-term CO2RR tests coupled with atomic-scale elucidation of changes in Cu/GNF reveal nanoparticles coarsening, and a simultaneous increase in the fraction of single Cu atoms. These changes in the catalyst structure make the onset of the CO2 reduction potential more negative, leading to less formate production at -0.38 V vs RHE, correlating with a less efficient competition of CO2 with H2O for adsorption on single Cu atoms on the graphitic surfaces, revealed by density functional theory calculations.

Among the different polyoxometalate compounds, Keggin heteropolyacids have been extensively used as catalysts in several acid-catalyzed reactions, due to their strong strength of Bronsted acidity. These metal–oxygen clusters have a highly versatile structure that allows their conversion to derivatives, which are catalysts that are much more efficient than their precursors, with a greater catalytic activity in a plethora of reactions of industrial interest. Particularly, due to the inevitable exhaustion of fossil sources, reactions to valorize biomass have attracted significant attention, since it is a precious renewable raw material that can provide fine chemicals or fuels, minimizing our dependence on petroproducts. Biorefinery processes can produce platform molecules to achieve this goal. In this review, the recent advances achieved in the development of routes to converting biomass feedstocks to levulinic acid and furfural, which are valuable ingredients in biorefinery processes, using Keggin heteropolyacid catalysts were assessed.

Rheumatoid arthritis (RA) is a chronic and debilitating condition that affects a significant number of individuals worldwide. Unfortunately, the currently available therapeutic approaches often yield unsatisfactory results and may be accompanied by harmful side effects. A medicinal plant called Psidium glaziovianum Kiaersk has potential benefits in the treatment of this condition due to its anti-inflammatory and analgesic properties. In this study, our objective was to investigate the potential therapeutic effects of P. glaziovianum essential oil (PgEO) in alleviating arthritis symptoms in mice induced by Complete Freund’s Adjuvant (CFA). The effect of P. glaziovianum essential oil was evaluated in mice with Complete Freund’s Adjuvant (CFA)-induced arthritis. Edema sizes, macroscopic and radiographic images, cytokine levels, and oxidative stress were evaluated. Administration of PgEO at dosages of 50 and 100 mg/kg effectively prevented CFA-induced osteoarticular changes in arthritic mice, resulting in a significant reduction in joint damage. Additionally, the PgEO treatment exhibited the ability to minimize edema, a common symptom associated with arthritis. Furthermore, PgEO can modulate the levels of pro-inflammatory cytokines and oxidative stress, both of which play crucial roles in the progression of the disease. In conclusion, our study suggests that PgEO holds great potential as a natural therapeutic agent for rheumatoid arthritis.

Hyaluronic acid (HA)-based hydrogels offer a promising approach for soft tissue application due to their biocompatibility, tunable mechanical properties, ability to mimic the extracellular matrix, and capacity to support cell adhesion and proliferation. In this work, bioadhesive composite hydrogels were developed by integrating graphite derivatives (EG) into a dopamine-modified HA matrix (HA-Cat), which enhances tissue adhesion through catechol groups that mimic mussel-inspired adhesion mechanisms. The EG was functionalized via 1,3-dipolar cycloaddition reaction (f-EG), that allowed the anchoring of silver nanoparticles (f-EG-Ag) and grafting of hydrocaffeic acid (f-EG-Cat) on the functionalized EG surfaces. The hydrogels were produced by oxidative crosslinking of HA-Cat under mild basic pH conditions using sodium periodate. Indirect in vitro assays using L929 fibroblast cells showed high biocompatibility and enhanced cell proliferation at optimized composite hydrogel concentrations. These findings suggest that composite hydrogels could find an application as bioactive, adhesive scaffolds for the regeneration of soft tissues, where they can facilitate localized agent delivery and integration with the host tissue.

(1) Background: The percentage of breast augmentations has increased in recent years alongside the frequency of implant removals. Musculoskeletal and postural disorders are often overlooked during this removal process. Research indicates that excess anterior load from breast implants can disrupt postural control and potentially lead to short- or long-term musculoskeletal dysfunction. This study aims to evaluate the immediate changes in postural control after artificial breast augmentation in healthy female volunteers. (2) Methods: Spinal angles, the center of pressure (CoP), and electromyographic activity of the spinal muscles were recorded in the static position and during the functional reach test (FRT) without and with implants of different volumes (220 mL, 315 mL, and 365 mL). Subjective perceptions of effort, comfort, weight, and performance in the FRT were also assessed. (3) Results: Statistical differences were significant in the scapular elevator during the one-minute standing position (lower activation with the 220 mL implant compared to the control and 315 mL) and in the trapezius muscles during the FRT (lower activation in the upper trapezius in the 315 mL vs. control in the reach phase and 220 mL vs. control in the return phase and higher activation in the lower trapezius in the 315 and 365 mL vs. control in the reach phase). Additionally, significant differences were identified in the performance of the FRT and the associated subjective perceptions. (4) Conclusions: Breast implants with sizes of 220, 315, and 365 mL can alter scapular neuromuscular control, but these differences do not seem substantial enough to result in negative biomechanical effects in the short-term analysis.

Musculoskeletal disorders are prevalent among agricultural workers, increasing the risk of work-related diseases due to manual labor, repetitive tasks, and prolonged postures. This study evaluates the association between physical behaviors during work and non-work, measured objectively, and musculoskeletal pain in the neck, upper back, and lower back in viticulture workers. A cross-sectional quantitative study was conducted with 75 viticulturists of both sexes aged 18 years or older. An accelerometer measured physical behaviors (lying down, sitting, standing, moving, walking, and sleeping) during work and non-work periods. Pain intensity was quantified using a 0–10 scale and categorized as “Low” and “High” pain intensity. Binary logistic regression tested the association between pain and time spent on physical behaviors. Results indicated a high prevalence of pain: 46.7% cervical, 52% upper back, and 60% lower back. Standing was the most common behavior during work, while lying and sitting were predominant during non-work. An increased sleeping time was associated with a decreased probability of experiencing high-intensity neck pain. Increased time spent lying down during non-work hours was associated with an increased probability of experiencing high-intensity upper back pain. No physical behavior was associated with high-intensity lower back pain. In conclusion, sedentary behaviors worsen upper back pain, and sleep reduces neck pain in viticulture workers.