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Superconducting fault current limiters (SFCLs) are recognized as one of the large-scale applications of high-temperature superconducting (HTS) materials with the highest potential to reach the commercial market. They can be integrated into multiple locations in electrical grids, contributing to the electrification of the energy system and, thus, to the Energy Transition. While limiting the levels of short-circuit currents, SFCLs allow, e.g., increasing the penetration of renewable generation while keeping the ratings of existing protections and postponing investments by utilities. Several topologies of SFCL have been developed, while the most technologically mature are the resistive and inductive ones. Among the latter, two different types have highlighted, namely the saturated cores and the transformer-type SFCL, which is focused on in this paper. This SFCL behaves as a short-circuited transformer, where its secondaries are made of HTS tape. Voltages are induced in the HTS short-circuited secondaries by the primaries (grid lines), and consequently, AC losses are generated. These should be estimated a priori to design the cryogenic system. When connected, e.g., in a busbar coupling or a transformer feeder in the distribution grid, SFCLs allow operating transformers in parallel, improving grid stability, among other advantages. Yet, the presence of single-phase loads in distribution grids leads to unbalanced currents, affecting the amount of AC losses. In this paper, the impact of unbalanced currents on the AC losses of a transformer-type SFCL, and its consequences in the design of the cryogenic system, are analyzed through extensive experimental measurements.

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder. Antiamyloid antibody treatments modestly slow disease progression in mild dementia due to AD. Emerging evidence shows that homeostatic dysregulation of the brain immune system, especially that orchestrated by microglia, plays an important role in disease onset and progression. Thus, a major question is how to modulate the phenotype and function of microglia to treat AD. Xenon (Xe) gas is a noble gas used in human patients as an anesthetic and a neuroprotectant used for treating brain injuries. Xe penetrates the blood-brain barrier, which could make it an effective therapeutic. To assess the effect of Xe on microglia and AD pathology, we designed a custom Xe inhalation chamber and treated several mouse models of AD with Xe gas. Xe treatment induced mouse microglia to adopt an intermediate activation state that we have termed pre–neurodegenerative microglia (pre-MGnD). This microglial phenotypic transition was observed in mouse models of acute neurodegeneration and amyloidosis (APP/PS1 and 5xFAD mice) and tauopathy (P301S mice). This microglial state enhanced amyloid plaque compaction and reduced dystrophic neurites in the APP/PS1 and 5xFAD mouse models. Moreover, Xe inhalation reduced brain atrophy and neuroinflammation and improved nest-building behavior in P301S mice. Mechanistically, Xe inhalation induced homeostatic brain microglia toward a pre-MGnD state through IFN-γ signaling that maintained the microglial phagocytic response in APP/PS1 and 5xFAD mice while suppressing the microglial proinflammatory phenotype in P301S mice. These results support the translation of Xe inhalation as an approach for treating AD.

Postgraduate training is moving from face-to-face workshops or courses to online learning to help increase access to knowledge, expertise and skills, and save the cost of face-to-face training. However, moving from face-to-face to online learning for many of us academics is intimidating, and appears even more difficult without the help of a team of technologists. In this paper, we describe our approach, our experiences and the lessons we learnt from converting a Primer in Systematic Reviews face-to-face workshop to a 6-week online course designed for healthcare professionals in Africa. We learnt that the team needs a balance of skills and experience, including technical know-how and content knowledge; that the learning strategies needed to achieve the learning objectives must match the content delivery. The online approach should result in both building knowledge and developing skills, and include interactive and participatory approaches. Finally, the design and delivery needs to keep in mind the limited and expensive internet access in some resource-poor settings in Africa.

Spontaneous tumor lysis syndrome is a rare emergency in onco-nephrology that results from extensive cancer cell lysis independent of antitumoral therapy. It is common among hematological tumors and can be rarely seen with solid tumors. In medical literature, there is only one case report with spontaneous tumor lysis syndrome in renal cell carcinoma and it was associated with metastases. To the best of our knowledge, this is the first report of spontaneous tumor lysis syndrome in non-metastatic renal cell carcinoma.

Serum soluble Fas (sFas) levels are associated with erythropoietin (Epo) hyporesponsiveness in patients with chronic kidney disease (CKD). Whether sFas could predict the need for erythropoiesis-stimulating agent (ESA) usage and its influence in erythropoiesis remain unclear. We evaluated the relation between sFas and ESA therapy in patients with CKD with anemia and its effect on erythropoiesis in vitro. First, we performed a retrospective cohort study with 77 anemic patients with nondialysis CKD. We performed in vitro experiments to investigate whether sFas could interfere with the behavior of hematopoietic stem cells (HSCs). HSCs were isolated from umbilical cord blood and incubated with recombinant sFas protein in a dose-dependent manner. Serum sFas positively correlated with Epo levels (r= 0.30, P= 0.001) but negatively with hemoglobin (r= −0.55, P< 0.001) and glomerular filtration rate (r= −0.58, P< 0.001) in patients with CKD at baseline. Elevated sFas serum levels (4,316 ± 897 vs. 2,776 ± 749, P< 0.001) with lower estimated glomerular filtration rate (26.2 ± 10.1 vs. 33.5 ± 14.3, P= 0.01) and reduced hemoglobin concentration (11.1 ± 0.9 vs. 12.5 ± 1.2, P< 0.001) were identified in patients who required ESA therapy compared with patients with non-ESA. Afterward, we detected that the sFas level was slight correlated with a necessity of ESA therapy in patients with nondialysis CKD and anemia. In vitro assays demonstrated that the erythroid progenitor cell frequency negatively correlated with sFas concentration (r= −0.72, P< 0.001). There was decreased erythroid colony formation in vitro when CD34+HSCs were incubated with a higher concentration of sFas protein (1.56 ± 0.29, 4.33 ± 0.53, P< 0.001). Our findings suggest that sFas is a potential predictor for ESA therapy in patients with nondialysis CKD and that elevated sFas could affect erythropoiesis in vitro.

Molecular self-assembly is a process ubiquitous in nature that refers to the spontaneous assembly of molecules in order to generate supramolecular structures through noncovalent interactions. Such a natural mechanism can be mimicked to modulate the fabrication of novel materials. The secret underlying the production of successful self-assembled materials lies on the careful selection of its building blocks. Control over the final architecture may be achieved by adjusting the size, shape and surface chemistry of these building blocks. Peptides are promising candidates as monomers for self-assembly, in part, due to the variety of amino acids which comprise different chemical functionalities. Such chemical diversity allows several interactions to take place, such as hydrogen bonding, hydrophobic effects or electrostatic interactions. In addition to design versatility, an increasing understanding of protein and peptide folding mechanisms allows the rational design of the monomer and its final assembly. Peptides have great potential for biomedical applications due to their inherent biocompatibility and biodegradability. In fact, self-assembled peptide-based biomaterials have been developed for the production of 3D scaffolds for tissue repair and regeneration and therapeutic drug delivery. Since peptides are bioactive molecules, its applications may go far beyond the fabrication of inactive architectures. Inherently functional materials may also be produced. In this review, we explore the different strategies adopted by scientists in the fabrication of peptide-based self-assembled biomaterials and provide a comprehensive overview of the mechanisms governing it.

In this paper, we propose a recommendation model to assist users find relevant courses for public tenders. The recommendations are computed based on the user study activity at Atepassar.com, a web-based learning environment for public tender candidates. Unlike traditional academic-oriented recommender systems, our approach takes into account crucial information for public tender candidates such as salary offered by public tenders and location where the exams take place. Technically, our recommendations rely on content-based techniques and a location reasoning method in order to provide users with most feasible courses. Results from a real-world dataset indicate reasonable improvement in recommendation quality over compared baseline models – we observed about 11 precision improvement and 12.7% of recall gain over the best model compared – demonstrating the potential of our approach in recommending personalised courses.

Intensive insulin treatment is associated with an increased risk of hypoglycaemia. The purpose of this study was to evaluate two different strategies: tight glucose control (TGC) versus intermediate glucose control (IGC). In this quasi-experimental study, 130 critically ill patients were assigned to receive either the TGC protocol (n=65), according to which blood glucose levels were maintained between 4.4 and 6.1 mmol/l, or the IGC protocol (n=65), according to which blood glucose levels were maintained between 4.4 and 8.0 mmol/l. A total of 52 subjects (40%) were diabetic and 63 (49%) were septic. In the IGC group, glucose levels were stabilised in the target range for a longer period of time when compared to the TGC group (63 vs 41%, P <0.001). The median capillary blood glucose level was 6.7 mmol/l in the TGC group (6.2 to 7.2) and 7.9 mmol/l (7.0 to 8.5) in the IGC group (P <0.001). The incidence of hypoglyacemia less than 2.2 mmol/l was 21.5% in the TGC group and 1.5% in the IGC group (P <0.001), and the incidence of hypoglycaemia less than 3.3 mmol/l was 67.7 and 26.2% (P <0.001) in the two groups, respectively. Diabetes (odds ratio 2.88, CI 1.22 to 6.84) and the TGC protocol (odds ratio 7.39, CI 3.15 to 17.35) were identified as independent risk factors for hypoglycaemia less than 3.3 mmol/l. Mechanical ventilation (odds ratio 4.33, CI 1.16 to 16.13), medical illness (odds ratio 2.88, CI 1.20 to 6.99) and hypoglycaemia (<3.3 mmol/l) (odds ratio 2.99, CI 1.21 to 7.41) were independent factors associated with mortality. TGC is difficult to accomplish in routine intensive care unit settings and is associated with a significant increase in the incidence of hypoglycaemia. Hypoglycaemia <3.3 mmol/l is an independent risk factor for in-hospital mortality.