Techno-Economic Feasibility Analysis through Optimization Strategies and Load Shifting in Isolated Hybrid Microgrids with Renewable Energy for the Non-Interconnected Zone (NIZ) of Colombia

In developing countries, electrification in remote areas, where access to energy is limited or null, has been one of the biggest challenges in recent years. Isolated microgrids with renewable generation are an efficient alternative for the energy supply in these areas. The objective of this work was to analyse the techno-economic viability of 6 isolated microgrids in different locations in the non-interconnected zone of Colombia, considering different climatic conditions, the availability of renewable resources, the current consumption profile, and a modified profile applying demand-side management. Modelling and simulation were performed considering storage systems based on lithium and lead-acid batteries. The resulting simulations provide the optimal system cost, emissions levels, electricity cost and battery lifetime. This study demonstrates that isolated hybrid microgrids with renewable energy are a feasible alternative to solve access to energy problems, reducing the need for diesel generators and optimizing the use of renewable energies and battery-based storage systems

La elección de centro como mecanismo de segregación social

El presente artículo pretende aportar más evidencias acerca de los efectos de la libre elección de centro escolar en la igualdad de oportunidades y, por tanto, en la equidad del sistema educativo, a partir de las experiencias y discurso de las propias familias. Este trabajo es parte de un estudio empírico mucho más amplio realizado en Zaragoza durante los años 2013-2015, titulado La elección de centro escolar en Aragón: Razonamientos y estrategias de los padres en la elección de centro escolar. De las entrevistas (43 en profundidad) y cuestionarios (1837 familias) se plantean tres factores que determinan la participación de los padres en el proceso de elección: amplitud, diversidad y calidad de laoferta educativa.Se resaltan dos variables que condicionan fuertemente la participación de las familias en la elección de centro: el nivel de formación de los padres y la renta familiar, que determinan que, aunque haya colegios elegibles, no siempre son accesibles a todas las familias. Todos tienen oportunidades para elegir, pero estas se reducen para los que tienen menos. Esta relación positiva tiene un nombre: desigualdad, funcionando como un mecanismo silencioso pero eficaz de segregación social. Se concluye que la libertad de elección per seno garantiza una igualdadde oportunidades y que, si no va acompañada de políticas que busquen reducir las desigualdades de partida que hay entre las familias, la libertad de elección se convierte en una forma subliminal de segregación social. The aim of this article is to provide more evidence regarding the effects of the free choice of school on equal opportunities, and, thus, on the equity of the educational system, based on the experiences and statements of families themselves. This work is part of a much broader empirical study carried out in Zaragoza in 2013-2015, entitled "Choosing a school in Aragon: parental reasoning and strategies in choosing a school"). The interviews (43 done in depth) and questionnaires (covering 1 837 families) raised three factors that determine parental participation in the selection process: scope, diversity, and quality of the educational offer. Two variables are highlighted that strongly affect family participation in the choice of school: the level of parental education, and family income, which determine the fact that, although there are eligible schools, they are not always accessible to all families. All have the opportunity to choose, but those opportunities are fewer for those who have less. That direct relationship has a name: inequality, functioning as a silent but effective mechanism for social segregation. The conclusion is that freedom of choice per se does not guarantee equal opportunities, and that, if it does not go hand-in-hand with policies aimed at reducing the initial inequalities that exist between families, freedom of choice becomes a subliminal form of social segregation that exists between families, freedom of choice becomes a subliminal form of social segregation

Characterization and wear performance of boride phases over tool steel substrates

This research work was conducted to characterize boride phases, obtained from the powder-pack process, on AISI H13 and D2 steel substrates, and investigate their tribological behavior. The boriding was developed at a temperature of 1273 K with an exposure time of 8 h. X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were conducted on the borided material to characterize the presence of the FeB, Fe2B, and CrB phases and the distribution of heavy elements on the surface of the substrates. The adherence of the boride layers was evaluated, in a qualitative form, through the Daimler-Benz Rockwell-C indentation technique. Sliding wear tests were then performed using a reciprocating wear test machine. All tests were conducted in dry conditions at room temperature. A frequency of 10 Hz and 15-mm sliding distance were used. The applied Hertzian pressure was 2.01 GPa. Scanning electron microscopy was used to observe and analyze the wear mechanisms. Additionally, the variation of the friction coefficient versus the number of cycles was obtained. Experimental results showed that the characteristic wear mechanism for the borided surface was plastic deformation and mild abrasive wear; for unborided substrates, cracking and spalling were observed

Scaling of Aharonov-Bohm couplings and the dynamical vacuum in gauge theories

Recent results on the vacuum polarization induced by a thin string of magnetic flux lead us to suggest an analogue of the Copenhagen `flux spaghetti' QCD vacuum as a possible mechanism for avoiding the divergence of perturbative QED, thus permitting consistent completion of the full, nonperturbative theory. The mechanism appears to operate for spinor, but not scalar, QED.Comment: 11 pages, ITP-SB-92-40, (major conceptual evolution from original

Probability of detecting germline BRCA1/2 pathogenic variants in histological subtypes of ovarian carcinoma:A meta-analysis

Background: Histology restricted genetic predisposition testing of ovarian carcinoma patients is a topic of debate as the prevalence of BRCA1/2 pathogenic variants (PVs) in various histological subtypes is ambiguous. Our primary aim was to investigate the proportion of germline BRCA1/2 PVs per histological subtype. Additionally, we evaluated (i) proportion of somatic BRCA1/2 PVs and (ii) proportion of germline PVs in other ovarian carcinoma risk genes. Methods: PubMed, EMBASE and Web of Science were systematically searched and we included all studies reporting germline BRCA1/2 PVs per histological subtype. Pooled proportions were calculated using a random-effects meta-analysis model. Subsets of studies were used for secondary analyses. Results: Twenty-eight studies were identified. The overall estimated proportion of germline BRCA1/2 PVs was 16.8% (95% CI 14.6 to 19.2). Presence differed substantially among patients with varying histological subtypes of OC; proportions being highest in high-grade serous (22.2%, 95% CI 19.6 to 25.0) and lowest in clear cell (3.0%, 95% CI 1.6 to 5.6) and mucinous (2.5%, 95% CI 0.6 to 9.6) carcinomas. Somatic BRCA1/2 PVs were present with total estimated proportion of 6.0% (95% CI 5.0 to 7.3), based on a smaller subset of studies. Germline PVs in BRIP1, RAD51C, RAD51D, PALB2, and ATM were present in approximately 3%, based on a subset of nine studies. Conclusion: Germline BRCA1/2 PVs are most frequently identified in high-grade serous ovarian carcinoma patients, but are also detected in patients having ovarian carcinomas of other histological subtypes. Limiting genetic predisposition testing to high-grade serous ovarian carcinoma patients will likely be insufficient to identify all patients with a germline PV

Ubiquitinome Profiling Reveals <i>in Vivo</i> UBE2D3 Targets and Implicates UBE2D3 in Protein Quality Control

Ubiquitination has crucial roles in many cellular processes, and dysregulation of ubiquitin machinery enzymes can result in various forms of pathogenesis. Cells only have a limited set of ubiquitin-conjugating (E2) enzymes to support the ubiquitination of many cellular targets. As individual E2 enzymes have many different substrates and interactions between E2 enzymes and their substrates can be transient, it is challenging to define all in vivo substrates of an individual E2 and the cellular processes it affects. Particularly challenging in this respect is UBE2D3, an E2 enzyme with promiscuous activity in vitro but less defined roles in vivo. Here, we set out to identify in vivo targets of UBE2D3 by using stable isotope labeling by amino acids in cell culture–based and label-free quantitative ubiquitin diGly proteomics to study global proteome and ubiquitinome changes associated with UBE2D3 depletion. UBE2D3 depletion changed the global proteome, with the levels of proteins from metabolic pathways, in particular retinol metabolism, being the most affected. However, the impact of UBE2D3 depletion on the ubiquitinome was much more prominent. Interestingly, molecular pathways related to mRNA translation were the most affected. Indeed, we find that ubiquitination of the ribosomal proteins RPS10 and RPS20, critical for ribosome-associated protein quality control, is dependent on UBE2D3. We show by Targets of Ubiquitin Ligases Identified by Proteomics 2 methodology that RPS10 and RPS20 are direct targets of UBE2D3 and demonstrate that the catalytic activity of UBE2D3 is required to ubiquitinate RPS10 in vivo. In addition, our data suggest that UBE2D3 acts at multiple levels in autophagic protein quality control. Collectively, our findings show that depletion of an E2 enzyme in combination with quantitative diGly-based ubiquitinome profiling is a powerful tool to identify new in vivo E2 substrates, as we have done here for UBE2D3. Our work provides an important resource for further studies on the in vivo functions of UBE2D3.Dutch Ministry of Health KWF-NKI2012- 5305Dutch Cancer Society 11369/2017-

The most efficient and effective BRCA1/2 testing strategy in epithelial ovarian cancer:Tumor-First or Germline-First?

Objective: Genetic testing in epithelial ovarian cancer (OC) is essential to identify a hereditary cause like a germline BRCA1/2 pathogenic variant (PV). An efficient strategy for genetic testing in OC is highly desired. We evaluated costs and effects of two strategies; (i) Tumor-First strategy, using a tumor DNA test as prescreen to germline testing, and (ii) Germline-First strategy, referring all patients to the clinical geneticist for germline testing.Methods: Tumor-First and Germline-First were compared in two scenarios; using real-world uptake of testing and setting implementation to 100%. Decision analytic models were built to analyze genetic testing costs (including counseling) per OC patient and per family as well as BRCA1/2 detection probabilities. With a Markov model, the life years gained among female relatives with a germline BRCA1/2 PV was investigated.Results: Focusing on real-world uptake, with the Tumor-First strategy more OC patients and relatives with a germline BRCA1/2 PV are detected (70% versus 49%), at lower genetic testing costs (€1898 versus €2502 per patient, and €2511 versus €2930 per family). Thereby, female relatives with a germline BRCA1/2 PV can live on average 0.54 life years longer with Tumor-First compared to Germline-First. Focusing on 100% uptake, the genetic testing costs per OC patient are substantially lower in the Tumor-First strategy (€2257 versus €4986).Conclusions: The Tumor-First strategy in OC patients is more effective in identifying germline BRCA1/2 PV at lower genetic testing costs per patient and per family. Optimal implementation of Tumor-First can further improve detection of heredity in OC patients.</p