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Analyzing rubber waste is crucial for value-added recycling, but the multitude of ingredients in vulcanized networks makes it challenging to characterize cross-linked rubbers. A combination of analytical techniques is usually required. In this study, two complementary characterization techniques, based on Fourier transform infrared (FTIR) spectroscopy and derivative thermogravimetric analysis (DTGA) were applied to analyze the structural, physical, and thermal behavior of ground tire rubber (GTR) samples devulcanized by two different processes. A set of samples was devulcanized by only microwaves (MW) while another set was treated with a combination of a thermochemomechanical (TM) process, which included the use of a devulcanization aid such as benzoyl peroxide, and microwaves. The combined technique proved to be more efficient in terms of the degree of devulcanization, significantly reducing the cross-linking density. However, the combined thermochemomechanical and microwave (TM/MW) devulcanization process resulted in greater degradation of the main rubber chains in the cross-linked network compared to the process using only microw [ABSTRACT FROM AUTHOR]

The viscoelastic behavior and reinforcement mechanism of polyethylene glycol (PEG) as an interfacial modifier in green tire tread composites were investigated in this study. The results show a clear positive effect on overall performance, and it significantly improved all the parameters of the "magic triangle" properties, the abrasion resistance, wet grip and ice traction, as well as the tire rolling resistance, simultaneously. For the preparation of the compounds, two mixing steps were used, as PEG 4000 was added on the second stage in order to avoid the competing reaction between silica/PEG and silanization. Fourier transform infrared spectroscopy (FTIR) confirmed that PEG could cover the silanol groups on the silica surface, resulting in the shortening of cure times and facilitating an increase of productivity. At low content of PEG, the strength was enhanced by the improvement of silica dispersion and the slippage of PEG chains, which are chemically and physically adsorbed on silica surface, but the use of excess PEG uncombined with silica in the compound, i.e., 5 phr, increases the possibility to shield the disulfide bonds of bis(3-(triethoxysilyl)-propyl) tetrasulfide (TESPT), and, thus, the properties were deteriorated. A constrained polymer model was proposed to explain the constrained chains of PEG in the silica-loaded composites on the basis of these results. An optimum PEG content is necessary for moderately strong matrix–filler interaction and, hence, for the enhancement in the mechanical properties. [ABSTRACT FROM AUTHOR]

This study examines the potential use of sodium alginate (SA) biopolymer as an environmentally sustainable agent for the stabilization of rubberized soil blends prepared using a high plasticity clay soil and tire-derived ground rubber (GR). The experimental program consisted of uniaxial compression and scanning electron microscopy (SEM) tests; the former was performed on three soil-GR blends (with GR-to-soil mass ratios of 0%, 5% and 10%) compacted (and cured for 1, 4, 7 and 14 d) employing distilled water and three SA solutions—prepared at SA-to-water (mass-to-volume) dosage ratios of 5, 10 and 15 g/L—as the compaction liquid. For any given GR content, the greater the SA dosage and/or the longer the curing duration, the higher the uniaxial compressive strength (UCS), with only minor added benefits beyond seven days of curing. This behavior was attributed to the formation and propagation of so-called "cationic bridges" (developed as a result of a "Ca2+/Mg2+ ⟷ Na+ cation exchange/substitution" process among the clay and SA components) between adjacent clay surfaces over time, inducing flocculation of the clay particles. This clay amending mechanism was further verified by means of representative SEM images. Finally, the addition of (and content increase in) GR—which translates to partially replacing the soil clay content with GR particles and hence reducing the number of available attraction sites for the SA molecules to form additional cationic bridges—was found to moderately offset the efficiency of SA treatment. [ABSTRACT FROM AUTHOR]

Dried blood spots (DBS) are a reliable tool to diagnose viremic hepatitis C virus (HCV) infection. We evaluated the clinical performance of a DBS‐based molecular assay for the assessment of cure and reinfection after on‐site treatment at a harm reduction center (HRC). Genotyping from DBS samples was also assessed to discriminate reinfection from treatment failure. People who inject drugs (PWID) from an ongoing test‐and‐treat pilot at the largest HRC in Barcelona were included in the study. HCV‐RNA detection from DBS collected after treatment (with follow‐up at 12, 36, and 60 weeks) was compared with a molecular point‐of‐care test using finger‐stick blood (GeneXpert). Baseline and follow‐up DBS samples were genotyped by NS5B sequencing or commercial real‐time PCR. Among treated patients, 193 follow‐up DBS samples were tested. The DBS‐based assay showed 100% specificity (129/129), and sensitivity ranged from 84.4% to 96.1% according to different viral load cut‐offs (from detectable to 3000 IU/mL). Sensitivity as test of cure (follow‐up 12) ranged from 85.1% to 97.4%. Among the 64 patients with recurrent viremia, 10.9% had low viral loads (≤1000 IU/mL); HCV genotyping allowed us to classify 73.5% of viremic cases either as reinfection or as treatment failure. DBS samples are useful to assess cure and differentiate reinfection from relapse after HCV antiviral treatment in the real world, facilitating decentralization of treatment and posttreatment follow‐up in PWID. However, a fraction of patients presented with low viral loads, limiting viremia detection and genotyping in DBS and, therefore, repeat testing is recommended. [ABSTRACT FROM AUTHOR]

The editors would like to express their sincere gratitude to the following reviewers for their precious time and dedication, regardless of whether the papers were finally published: Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that I Applied Sciences i maintains its standards for the high quality of its published papers. [Extracted from the article]

Background and Aim: Accurate information on the epidemiology of hepatitis C and B infection is mandatory to establish a national/regional plan. We aim to update the prevalence of hepatitis C and B infection in Catalonia using point‐of‐care tests to analyze the risk factors related and to implement a linkage‐to‐care circuit. Methods: This is a community‐based study. A random list of adult individuals was retrieved from censuses of primary care centers. Point‐of‐care tests for anti‐hepatitis C virus (HCV) and HBV surface antigen (HBsAg) and a questionnaire for risk factor assessment were performed. Positive results were validated and a circuit for linkage‐to‐care was established. Results: A total of 3328 individuals were included. The anti‐HCV and HBsAg overall prevalence were lower than expected [1.02%, 95% confidence interval (CI) 0.65–1.39; and 0.52%, 95% CI 0.26–0.77, respectively]. Anti‐HCV positive subjects were mostly (88%) autochthonous. The prevalence increased with age; only 12% were under age 40. The associated risk factors were drug use, blood transfusion, relative with HCV, and diabetes. Notably, the prevalence of active infection was only 0.49% (95% CI 0.23–0.74), 40% less than previously reported, reflecting the impact of direct acting antiviral therapy. Differently, HBsAg positive subjects were mostly foreign migrants (53%) with no other risk factors. Despite the implementation of a linkage‐to‐care circuit, one third of HBsAg positive subjects were lost. Conclusions: The prevalence of HCV infection was lower than previously reported, showing a strong impact of direct acting antiviral therapy in the last years. Because of hepatitis B universal vaccination, HBV infection in Catalonia is mainly associated with migrant population. Linkage‐to‐care in patients with hepatitis B was challenging and warrants additional efforts. [ABSTRACT FROM AUTHOR]

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