Real-time simulation of load-flow problems in electrical grids

In the present situation, the implementation of Smart Grids is one of the pressing challenges in the energy field, both for the improvement in efficiency it implies, as for its positive effects on the environment, since they facilitate the massive incorporation of renewable energy into the system. One problem that arises in the management of these networks is to simulate in realtime their associated load-flow problems, which allow the knowledge of the grid status and to respond in real time to manage power demands. This thesis examines how losses are evaluated in a network, that is, the difference between the generated and consumed power, when a photovoltaic generator is incorporated in one of its nodes. The needed calculations are explained, as well as the nonlinear system to solve, taking as test system a grid consisting of a three-phase generator, a transformer, and 100 equidistant nodes

Alterations in transcript abundance of bovine oocytes recovered at growth and dominance phases of the first follicular wave

<p>Abstract</p> <p>Background</p> <p>Oocyte developmental competence is highly affected by the phase of ovarian follicular wave. Previous studies have shown that oocytes from subordinate follicles recovered at growth phase (day 3 after estrus) are developmentally more competent than those recovered at dominance phase (day 7 after estrus). However, the molecular mechanisms associated with these differences are not well elucidated. Therefore, the objective of this study was to investigate transcript abundance of bovine oocytes retrieved from small follicles at growth and dominance phases of the first follicular wave and to identify candidate genes related to oocyte developmental competence using cDNA microarray.</p> <p>Results</p> <p>Comparative gene expression analysis of oocytes from growth and dominance phases and subsequent data analysis using Significant Analysis of Microarray (SAM) revealed a total of 51 differentially regulated genes, including 36 with known function, 6 with unknown function and 9 novel transcripts. Real-time PCR has validated 10 transcripts revealed by microarray analysis and quantified 5 genes in cumulus cells derived from oocytes of both phases. The expression profile of 8 (80%) transcripts (ANAXA2, FL396, S100A10, RPL24, PP, PTTG1, MSX1 and BMP15) was in agreement with microarray data. Transcript abundance of five candidate genes in relation to oocyte developmental competence was validated using Brilliant Cresyl Blue (BCB) staining as an independent model. Furthermore, localization of mRNA and protein product of the candidate gene MSX1 in sections of ovarian follicles at days 0, 1, 3 and 7 of estrous cycle showed a clear fluorescent signal in both oocytes and cumulus cells with higher intensity in the former. Moreover, the protein product was detected in bovine oocytes and early cleavage embryos after fertilization with higher intensity around the nucleus.</p> <p>Conclusion</p> <p>This study has identified distinct sets of differentially regulated transcripts between bovine oocytes recovered from small follicles at growth and dominance phases of the first follicular wave. The validation with independent model supports our notion that many of the transcripts identified here may represent candidate genes associated with oocyte developmental competence. Further specific functional analysis will provide insights into the exact role of these transcripts in oocyte competence and early embryonic development.</p

Cost-effectiveness of enforcing axle-load regulations: the Douala-N’Djamena corridor in Sub-Saharan Africa

Road conditions in Sub-Saharan Africa are typically poor, and only a subset of the newly constructed or rehabilitated roads reach their design life. Truck overloading generally causes this rapid deterioration. In Africa, there are few success stories on the imposition of axle-load limits. This study examines the existing regulations on the Douala-N'Djamena international road, which is the main transport corridor in Central Africa and the backbone for internal transport in Cameroon. It benefits from the detailed existing weighing data recorded since 1998 in the corridor's 10 weighing stations. This vast amount of traffic data, together with available information on road structure and deterioration over time, has been used to conduct an accurate calculation of load equivalency factors. The HDM 4 model has been applied to three scenarios between 2000 and 2015: (1) no axle-load control, (2) the real situation and (3) no overloading tolerance. Results show that axle-load regulations have been reasonably well applied in Cameroon and have contributed to maintaining the corridor in fair condition. In spite of the fact that significant traffic increases are presently counterbalancing the damage avoided by axle-load limits, benefits provided by axle-load control have been substantial: in the period of 2000–2015, every € invested or spent on axle-load control has generated more than €20 of savings in road user costs and in road maintenance and rehabilitation expenditure, which represents, in absolute terms, more than €500 million.Peer ReviewedPostprint (published version

Biotecnologia reproductiva en porcí: estat actual i reptes de futur

La biotecnologia reproductiva en porcí inclou les diverses tècniques d'anàlisi de la qualitat seminal i les tècniques de reproducció assistida. Els objectius fonamentals són garantir la seguretat biològica, permetre'n la traçabilitat i incrementar (o estabilitzar) el rendiment reproductiu. Entre les tècniques d'anàlisi de la qualitat seminal destaquem les de determinació de qualitat espermàtica (concentració, motilitat, viabilitat, integritat de membranes i del DNA), les de control de l'estat sanitari (PCR-RT per a detecció de virus i bacteris) i les de determinació del poder fecundant i de la resistència osmòtica. Entre les tècniques de reproducció assistida es practiquen la inseminació artificial (cervical, postcervical i intrauterina), la fecundació in vitro, la injecció intracitoplasmàtica d'espermatozoides, la vitrificació embrionària, la transferència embrionària no quirúrgica, la criopreservació espermàtica, el sexatge d'espermatozoides i d'embrions, el clonatge reproductiu i terapèutic i la transgènesi.Reproductive biotechnology in porcine includes several techniques of analysis of the seminal quality and techniques of assisted reproduction. The main goals are guaranteeing the biological security, allowing the traceability and increasing (or stabilizing) the reproductive yield. Among the techniques of analysis of the seminal quality we highlight those of sperm quality (concentration, motility, viability, integrity of membranes and DNA), those of sanitary control (PCR-RT for the detection of virus and bacteria) and those of determination of fertilizing ability and osmotic resistance. Among the assisted reproduction techniques, there is artificial insemination (cervical, postcervical and intrauterine), in vitro fertilization, intracytoplasmic injection of spermatozoa, embryonic vitrification, non surgical embryonic transfer, sperm cryopreservation, spermatozoa and embryos sexing, reproductive and therapeutic cloning, and transgenity

Protocol d'actuació davant de casos de febre vírica de Zika en l'àmbit obstètric i pediàtric de Catalunya

Virus del Zika; Obstetrícia; PediatriaZika virus; Obstetrics; PediatricsObstetricia; PediatríaAquest document dóna recomanacions d'actuació per a la prevenció, detecció i tractament del virus del Zika a Catalunya

SOCIB: the impact of new marine infrastructures in understanding and forecasting the coastal oceans: some examples from the Balearic Islands in the Mediterranean Sea

New monitoring technologies are being progressively implemented in coastal ocean observatories. As an example, gliders allow high resolution sampling, showing the existence of new features, such as submesoscale eddies with intense vertical motions that significantly affect upper ocean biogeochemical exchanges, an issue of worldwide relevance in a climate change context. SOCIB, is one of such systems, a new facility of facilities (covering from the coast to the open sea, and including among others a nearshore beach monitoring facility, HF radar, gliders and AUV’s, moorings, satellite, drifters and ARGO profilers, modelling), a scientific and technological infrastructure which is providing free, open, quality controlled and timely streams of oceanographic and coastal data and also modelling services. SOCIB takes profit of the strategic position of the Balearic Island at the Atlantic/Mediterranean transition area, one of the ‘hot spots’ of biodiversity in the world’s oceans. As an example of on-going SOCIB operations, since January 2011 sustained glider operations are in place in the Ibiza and Mallorca channels. The data centre is the core of SOCIB. The data management system created for gliders is an example of the new informatics capabilities for real time definition of mission planning, including adaptive sampling and real time monitoring using a Web tool that allows quick visualization and download. This type of new infrastructures, combined with new technologies and careful scientific analysis will allow new ways of international cooperation leading to major science breakthroughs in the very near future and new ways of science based coastal and ocean management.Peer Reviewe