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Electrical Characterization of Vanadium Flow Battery-Cell Test Facility (VFB-CTF): Early Results and Methods for Scaling Up
No full textTechnological enhancement plays a fundamental role in view of the proper design of industrial Flow Battery (FB) systems, which are recognized as one of the most promising solutions for stationary energy storage applications. This work presents the design, construction and early operation of a single-cell medium-size Vanadium Flow Battery (VFB) Cell Test Facility, dubbed VFB-CTF suitable to test materials and geometries in easily controllable and adjustable conditions. VFB-CTF is also capable of testing small VFB stacks. The test bench has been designed and built to accurately measure the main thermal, hydraulic, electric, and energetic quantities affecting the performance of VFBs. By extrapolating such measurements, the performance of large-scale RFB stacks can be estimated by means of analytical formulations built on similitude concepts. In this work, early experimental results i.e. polarization curves and Nyquist plots from Electrochemical Impedance Spectroscopy measurements of some of the most promising active materials for these applications, obtained from the world’s leading manufacturers, will be reported and discussed. Measurements provided by VFB-CTF can effectively be used to address criteria and metrics for the design of industrial-scale RFBs
Exploring the Link Between Telomeres and Mitochondria: Mechanisms and Implications in Different Cell Types
Get PDFTelomeres protect chromosome ends from damage, but they shorten with each cell division due to the limitations of DNA replication and are further affected by oxidative stress. This shortening is a key feature of aging, and telomerase, an enzyme that extends telomeres, helps mitigate this process. Aging is also associated with mitochondrial dysfunction, leading to increased reactive oxygen species (ROS) that exacerbate cellular damage and promote apoptosis. Elevated ROS levels can damage telomeres by oxidizing guanine and disrupting their regulation. Conversely, telomere damage impacts mitochondrial function, and activation of telomerase has been shown to reverse this decline. A critical link between telomere shortening and mitochondrial dysfunction is the DNA damage response, which activates the tumor suppressor protein p53, resulting in reduced mitochondrial biogenesis and metabolic disruptions. This highlights the bidirectional relationship between telomere maintenance and mitochondrial function. This review explores the complex interactions between telomeres and mitochondria across various cell types, from fibroblasts to sperm cells, shedding light on the interconnected mechanisms underlying aging and cellular function
Heart–Liver Interplay in Patients with Fontan Circulation
No full text: Background: The Fontan procedure has provided pediatric patients suffering from severe congenital heart disease the opportunity to reach adulthood. Increasingly, we encounter the liver repercussions of Fontan circulation, alongside a decline in heart function and exercise performance. This study aims to identify the univentricular heart malformations that are most susceptible to liver dysfunction; assess which markers of liver injury are essential for multidisciplinary clinical follow-up of Fontan patients; determine the optimal approach for evaluating liver function in Fontan patients; and explore how a congenital cardiology team can interpret the data and respond effectively to signs of organ failure. Methods: Cross-sectional clinical study including patients who underwent a Fontan procedure at the University Hospital of Padua between 1982 and 2017. Patients were admitted for elective hospitalization between June 2021 and June 2022 and underwent clinical assessment, laboratory tests, and instrumental examinations. Results: Seventy patients were included in the study. On admission, 48 patients (72%) were in New York Heart Association (NYHA) functional class I, and the cardiopulmonary exercise test was normal for age and gender. At laboratory tests, 56% of patients showed changes in NTproBNP values, most of whom had right-sided ventricular morphology. Liver function tests showed abnormal Gamma-Glutamyl Transferase (GGT) blood levels in 68%. On cardiac imaging, at least moderate atrioventricular valve insufficiency was found in 9% of cases. Fibroscan showed altered hepatic stiffness values in 25% of cases. Statistical analysis showed that systemic atrioventricular valve (SAVV) dysfunction was significantly associated with a reduction of maximum oxygen consumption (VO2 max) and hepatic stiffness. Conclusions: SAVV dysfunction is significantly responsible for worse functional outcomes and the development of hepatic fibrosis due to an increase in venous congestion. Setting up a careful multidisciplinary follow-up in these patients is mandatory for early detection of complications, prompt treatment, and better outcomes
“Omics” and Postmortem Interval Estimation: A Systematic Review
Get PDFPostmortem interval (PMI) estimation is a challenge of utmost importance in forensic daily practice. Traditional methods face limitations in accuracy and reliability, particularly for advanced decomposition stages. Recent advances in “omics” sciences, providing a holistic view of postmortem biochemical changes, offer promising avenues for overcoming these challenges. This systematic review aims at investigating the role of mass-spectrometry-based “omics” approaches in PMI estimation to elucidate molecular mechanisms underlying predictable time-dependent biochemical alterations occurring after death. A systematic search was performed, adhering to PRISMA guidelines, through “free-text” protocols in the databases PubMed, SCOPUS and Web of Science. The inclusion criteria were as follows: experimental studies analyzing, as investigated samples, animal or human corpses in toto or in parts and estimating PMI through MS-based untargeted omics approaches, with full texts in the English language. Quality assessment was performed using STROBE and ARRIVE critical appraisal checklists. A total of 1152 papers were screened and 26 included. Seventeen papers adopted a proteomic approach (65.4%), nine focused on metabolomics (34.6%) and two on lipidomics (7.7%). Most papers (57.7%) focused on short PMIs (120 days) (15.4%). Muscle tissue was the most frequently analyzed substrate (34.6% of papers), followed by liver (19.2%), bones (15.4%), cardiac blood and leaking fluids (11.5%), lung, kidney and serum (7.7%), and spleen, vitreous humor and heart (3.8%). Predictable time-dependent degradation patterns of macromolecules in different biological substrates have been discussed, with special attention to molecular insights into postmortem biochemical changes
Social representations of dementia. A qualitative inquiry into perspectives of people with dementia, professionals, and informal caregivers
No full textUsing a theoretical framework that underscores the social dimension of meaning-making processes, this study delved into the social representations of dementia in the Italian context and the personal meanings expressed by three distinct groups of participants. The study involved ninety-two episodic interviews with people living with dementia and those who had provided care as professionals or informal caregivers. The collected data underwent various types of analysis. A hierarchical descending analysis was initially conducted using IRaMuTeQ to elucidate the lexical worlds that form the shared idea of dementia. This was followed by a more interpretative thematic analysis using Atlas.ti. The results reveal the diverse perspectives of the groups in articulating the contents of social representations, which can guide actions in the care and management of the disease
Wood jam mobility in a morphologically active river in northern Chilean Patagonia
Get PDFWood is crucial in river systems, influencing both ecological and physical dynamics. Understanding its behaviour in relation to fluvial morphology is essential for effective watershed management, especially after extreme events. The tendency of wood to accumulate into wood jams (WJs) adds complexity, as these dynamics remain challenging to assess. This study explored the relationship between channel morphological changes and WJ mobility in the Blanco River, Chile, which was affected by a volcanic eruption in 2008–2009. The methodological approach involved utilising multi-temporal drone surveys conducted in 2018, 2019 and 2023, over a river segment with an area of 29.5 ha and a length of 2.2 km. First, the characterisation of morphological units, quantification of geomorphic changes, and classification of morphodynamic mechanisms were accomplished using orthophotos and robust Digital Terrain Models (DTM) of Difference (DoD). Then, WJ abundance, spatial arrangement and mobility were deri..
Toward a definition of valence as a quantity (IUPAC Technical Report)
Get PDFValence has a rich history in chemistry, as a bonding concept, in terms of quantitative context, and as a true quantity. In the latter, a survey preceding this project revealed differing perceptions of valence values and helped formulate candidate definitions. This IUPAC task group evaluated nine quantities behind eight alternative definitions on 39 chemical entities of 48 bonding formulas, each giving a set of meaningful values with mutual relationships. Given the reflection principle of IUPAC normative work, 15 comparative examples with high variation of these alternative valences for an element were selected, and chemistry articles in English searched for valence-termed quantities of the compared compounds to imply the definition behind the stated valence value, the frequency of such use, and the chemistry field. Summarized preferences for the alternative definitions show two main areas of use. Organic and physical chemists count valence as a number of two-electron bonds at the atom. Inorganic chemists working with semi-metallic and metallic elements use n-valent as an adjective for oxidation state. The diverse yet infrequent use cannot be covered by a single definition of the valence quantity. Clarity in articles that use valence as a quantity is essential and achievable by stating the intended context
Finding quantum codes via Riemannian optimization
Get PDFWe propose a novel optimization scheme designed to find optimally correctable subspace codes for a known quantum noise channel. To each candidate subspace code we first associate a universal recovery map, as if the code was perfectly correctable, and aim to maximize a performance functional that combines a modified channel fidelity with a tuneable regularization term that promotes simpler codes. With this choice optimization is performed only over the set of codes, and not over the set of recovery operators. The set of codes of fixed dimension is parametrized as a complex-valued Stiefel manifold: the resulting non-convex optimization problem is then solved by gradient-based local algorithms. When perfectly correctable codes cannot be found, a second optimization routine is run on the recovery Kraus map, also parametrized in a suitable Stiefel manifold via Stinespring representation. To test the approach, correctable codes are sought in different scenarios and compared to existing ones: three qubits subjected to bit-flip errors (single and correlated), four qubits undergoing local amplitude damping and five qubits subjected to local depolarizing channels. Approximate codes are found and tested for the previous examples as well pure non-Markovian dephasing noise acting on a 7/2 spin, induced by a 1/2 spin bath, and the noise of the first three qubits of IBM's ibm_kyoto quantum computer. The fidelity results are competitive with existing iterative optimization algorithms, with respect to which we maintain a strong computational advantage, while obtaining simpler codes
Peptide‐Drug Conjugate for Therapeutic Reprogramming of Tumor‐Associated Macrophages in Breast Cancer
Get PDFIn triple-negative breast cancer (TNBC), pro-tumoral macrophages promote metastasis and suppress the immune response. To target these cells, a previously identified CD206 (mannose receptor)-binding peptide, mUNO was engineered to enhance its affinity and proteolytic stability. The new rationally designed peptide, MACTIDE, includes a trypsin inhibitor loop, from the Sunflower Trypsin Inhibitor-I. Binding studies to recombinant CD206 revealed a 15-fold lower KD for MACTIDE compared to parental mUNO. Mass spectrometry further demonstrated a 5-fold increase in MACTIDE's half-life in tumor lysates compared to mUNO. Homing studies in TNBC-bearing mice shows that fluorescein (FAM)-MACTIDE precisely targeted CD206+ tumor-associated macrophages (TAM) upon intravenous, intraperitoneal, and even oral administration, with minimal liver accumulation. MACTIDE was conjugated to Verteporfin, an FDA-approved photosensitizer and YAP/TAZ pathway inhibitor to create the conjugate MACTIDE-V. In the orthotopic 4T1 TNBC mouse model, non-irradiated MACTIDE-V-treated mice exhibited anti-tumoral effects comparable to those treated with irradiated MACTIDE-V, with fewer signs of toxicity, prompting further investigation into the laser-independent activity of the conjugate. In vitro studies using bone marrow-derived mouse macrophages showed that MACTIDE-V excluded YAP from the nucleus, increased phagocytic activity, and upregulated several genes associated with cytotoxic anti-tumoral macrophages. In mouse models of TNBC, MACTIDE-V slowed primary tumor growth, suppressed lung metastases, and increased markers of phagocytosis and antigen presentation in TAM and monocytes, increasing the tumor infiltration of several lymphocyte subsets. MACTIDE-V is proposed as a promising peptide-drug conjugate for modulating macrophage function in breast cancer immunotherapy