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Electrochemical detection and oxidation pathway of fenproporex using 3D-printed electrodes in dietary and biological samples
Get PDFFenproporex (FPX) is an amphetamine-based stimulant banned in several countries due to its harmful side effects. Despite this, it remains illegally present in dietary supplements and is commonly abused by Brazilian truck drivers to prolong wakefulness. This study presents a novel electrochemical method for FPX determination using a 3D-printed electrode fabricated from a custom conductive filament comprising graphite (12 wt.%), carbon black (18 wt.%), recycled PLA (60 wt.%), and castor oil (10 wt.%). Surface activation via chemical–electrochemical treatment in alkaline medium (0.5 mol L⁻¹ NaOH) effectively removed the PLA, exposing conductive carbon particles, as confirmed by FTIR spectroscopy and SEM imaging. To our knowledge, this is the first electrochemical method reported for FPX detection. The oxidation mechanism involves the transfer of one electron and one proton. Square wave voltammetry (SWV) was optimized for FPX analysis in forensic samples, showing excellent linearity over two ranges (1–75 and 75–250 µmol L⁻¹; R² ' 0.99) and a detection limit of 0.14 µmol L⁻¹. The method displayed high selectivity, with no interference from common biological or forensic compounds. It was successfully applied to spiked dietary supplements and bovine serum samples, with recoveries from 92 ± 5% to 111 ± 1%, confirming its accuracy. This approach provides a low-cost, eco-friendly, and effective alternative for FPX screening in forensic and quality control contexts
Exploring Trauma-Informed Organizational Practices and Self-Care: Strengthening Resilience Factors among Child Welfare Workers
No full textObjective: Child welfare workers are at risk of secondary traumatic stress as a consequence of their work. Self-care strategies could help mitigate negative symptoms, improve well-being, and enhance resilience. This study explored associations between trauma-informed organizational practices and self-care behaviors among child welfare workers. Method: Data were collected in a Midwestern state, using an online, repeated cross-sectional survey. Participants were child welfare workers from public and private agencies. Surveys administered annually from 2020-2023 measured organizational activities, safety practices, and leadership practices. Self-care was assessed in terms of the number and frequency of self-care activities. Generalized estimating equations were used to analyze the associations between organizational practices and self-care, accounting for missing data. Results: This exploratory study found three types of trauma-informed organizational practices had positive and significant associations with both number and frequency of self-care activities. Specifically, resilience-building activities (b=0.04, p<.001), safety practices (b=0.04, p < .001), and leadership practices (b=0.04, p<.001) were linked to greater engagement in self-care. Additionally, these practices were associated with more frequent self-care (organizational resilience-building: b=0.18, p<.001; safety practices: b=0.16, p<.001; leadership practices: b=0.10, p<.001). Conclusions: Organizational strategies, including resilience-building, promoting safety, and supportive leadership, may influence workers' self-care behaviors. Findings suggest systemic changes are needed to enhance resilience, mitigate secondary traumatic stress, and improve retention. Future research should explore long-term impacts of organizational practices on job satisfaction, retention, and well-being
Early growth response 1 promotes RNA polymerase I-directed transcription and cancer growth by activating RRN3 expression
Get PDFEarly growth response 1 (EGR1) was identified as a positive regulator in Pol II- and Pol Ⅲ-directed transcription. Whether EGR1 modulates Pol Ⅰ-directed transcription remains unknown. Here, we report that EGR1 is present in the nucleoli of several cancer cell lines. EGR1 positively regulates the synthesis of Pol Ⅰ products and the proliferation of HeLa, HePG2, and AGS cells both in vitro and in vivo. EGR1 silencing increased R-loop formation and lncRNA PAPAS expression, which inversely correlated with Pol Ⅰ product levels. Mechanistically, EGR1 enhances the recruitment of Pol I transcription machinery factors to the rDNA promoter through interactions with these factors. The EGR1 DNA-binding domain mediates the interaction between EGR1 and Pol I machinery components. EGR1 activates RRN3 gene transcription by binding to the RRN3 gene promoter. Thus, EGR1 promotes Pol Ⅰ-directed transcription and cancer cell growth by both interacting with Pol I machinery factors and controlling RRN3 expression
Callinectes sapidus — coast to coast: Integrating stable isotope analysis and shotgun metagenomics to unravel trophic dynamics and microlitter ingestion across two Mediterranean sites
No full textThe increasing presence of microlitter in the marine environment poses a growing threat to aquatic organisms. This study investigates microlitter ingestion and trophic ecology of Callinectes sapidus from two populations of the Mediterranean basin: the Adriatic and Tyrrhenian Seas. To disentangle potential differences in feeding strategies between the populations, we adopted an integrated framework combining stable isotope analysis with shotgun metagenomic analysis of gastrointestinal contents, thus providing a complementary view of long-term trophic position and short-term dietary composition. Gastrointestinal analysis revealed microlitter ingestion in 39% of Adriatic and 50% of Tyrrhenian individuals, with 123 particles retrieved. Fibres dominated (94.3%), though composition varied regionally: Adriatic individuals ingested mainly cellulose-based microlitter (62.5%), whereas Tyrrhenian ones mostly synthetic polymers (61.4%). Eight chemical types were identified, with cellulose, polyethylene terephthalate, and resin-based polymers most abundant. Stable isotope analysis (δ15N and δ13C) indicated distinct trophic patterns: Adriatic population had higher δ15N (mean ± sd: 11.50 ± 2.27‰) and less depleted δ13C (−16.20 ± 1.52‰) compared to the Tyrrhenian one (δ15N: 9.01 ± 2.27‰; δ13C: −18.57 ± 0.88‰), suggesting region-specific feeding strategies. Shotgun metagenomics provided complementary information on prey composition, helping to characterise the opportunistic diet of C. sapidus . Overall, these findings highlight spatial differences in microlitter exposure and trophic dynamics, likely shaped by environmental availability and feeding behaviour. By integrating microlitter ingestion, stable isotope analysis, and metagenomics, this study provides insight into how C. sapidus interacts with anthropogenic and natural resources, emphasizing the feeding flexibility underlying its invasive success in Mediterranean Sea
Navigating international entrepreneurship while impacting regional development in the digital age
No full textThe study explores how international enterprises navigate expansion in other markets simultaneously contributing to the regional development. Such international enterprises use digital platforms and disruptive technologies to transform their business models. Digital platform adoption and technological integration accelerate internationalization efforts and facilitate regional economic growth. A new theoretical framework is built upon international entrepreneurship orientation and network capability, inductively evaluating a group of international enterprises located in the United Kingdom and Italy. This framework offers new insights and trends based on our emerging concepts such as 1. International attitude, cultural value and global orientation; 2. Digital business model driven towards internationalization; 3. Network and digital ecosystem integration, and 4. Multiplier effects for Regional Growth. Entrepreneurs and managers should strongly consider the development of these new concepts in expanding their business in global market. This also facilitated by the adoption of digital platforms that request an entrepreneurial orientation to handle a greater market uncertainty and diversity. being more digital
Numerical simulations for regenerator optimization in an experimental elastocaloric cooling prototype based on shape memory alloys
No full textThe SMACOOL (acronym for Shape Memory Alloy based elastocaloric CooLing system) project aims to develop a rotary elastocaloric-based air-conditioning system utilizing shape memory alloys as solid-state refrigerants. Solid-state refrigeration based on the elastocaloric effect offers a promising alternative to vapor compression systems, but it still faces major challenges such as low energy efficiency, mechanical fatigue of materials, and complex regenerator design. Addressing these issues is crucial to enable practical implementation in real cooling applications. In this study, a numerical investigation was carried out to optimize the regenerator design, comparing tension and compression loading modes and different geometries, namely parallel plates and spiral cross-sections. Model validation against experimental data and mesh independence analyses confirmed the reliability of the numerical approach. Finite element simulations revealed that compression mode outperforms tension, achieving cold-side temperature lifts up to 10 times higher and cooling powers up to 4 times higher under identical operating conditions. Spiral geometries showed up to 115% higher ΔTcold and up to 314% higher cooling power compared to parallel plates in Active elastocaloric Regenerative refrigeration cycle. In Heat Recovery cycle, the spiral regenerator achieved an increase up to: 123% for ΔTcold, 22% for cooling power and 55% for COP respect to parallel plates. The study also highlights that internal buckling prevention material negatively affects thermal performance. Based on these findings, a spiral compression regenerator was selected for the SMACOOL prototype, targeting enhanced energy efficiency and system durability
Arnold Toynbee, Why Britain must join Europe (1971).pdf (https://www.academia.edu/145740569/Arnold_Toynbee_Why_Britain_must_join_Europe_1971_)
No full textADDITIONS, INTEGRATIONS, CORRECTIONS AND SUPPLEMENTS TO THE BIBLIOGRAPHY OF ARNOLD JOSEPH TOYNBEE,
No. 561, Addition to Part I, Works by Arnold J. Toynbe