Observador de estado de un sistema de generación de energía de tipo celda de combustible PEM mediante un modelo lineal variante

Presentado al IV Congreso Nacional de Pilas de Combustible celebrado en Sevilla (España) del 16 al 18 de Junio de 2010.[ES]: En este trabajo se presenta el modelado de un sistema generador de energía basado en pilas de combustible PEM mediante un modelo variante con el punto de operación (modelo LPV). Dicho modelo ha sido obtenido mediante la linealización del modelo dinámico no lineal que ha sido previamente calibrado con datos reales de laboratorio. El modelo LPV obtenido está pensado para ser utilizado en el diseño de controladores y algoritmos de diagnóstico de fallos basados en modelos.[EN]: In this paper, the modelling of an energy generation systems based on PEM fuel cells through a model varying with the operating point (LPV model) is presented. This model has been obtained through the linearization of the non-linear dynamic model that was previously calibrated using real data from lab. The LPV model obtained is intended to be used for the controller design and model-based fault diagnosis.Los autores quieren agradecer ayuda otorgada por parte del Concejo Nacional de Ciencia y Tecnología (CoNACYT) y el soporte recibido al grupo de investigación SAC por parte de la Comisión de Recerca de la Generalitat de Catalunya (Grup SAC ref. 2009SGR1491) y por la CICYT (ref. HYFA DPI-2008-1999) del Ministerio de Educación del Estado Español.Peer Reviewe

Carbon Tetrachloride as Thermoporometry Liquid-probe to Study the Cross linking of Styrene Copolymer Networks

Mesh Size Distributions (MSDs) of swollen cross linked styrene copolymer networks have been measured by thermoporometry using CCl4 as a probe liquid. All numerical relationships required for the calculation of the MSD were established for both the liquid-to-solid and the solid-to-solid thermal transitions of CCl4 and successfully validated on test samples. It was found that the polymer network, for both thermally and photo-cross linked materials, was completely built in about four hours of exposure. A clear correlation was established between the average mesh size of the swollen polymer network on the one hand and the benzoyl peroxide groups content and swelling ratio on the other hand

Характеристика екстер’єрних ознак карпатських бджіл різного походження

New selection achievements obtained in beekeeping. The study and analysis of the literature on the hybridization of beekeeping expediency pure breeding of bees and the use and mizhtypovyh intrabreed interline hybrids, which are little inferior performance interbreed, but have a significant advantage, because the preserved purity of the breed. Found that the signs describing the size of the abdomen of bees, long proboscis and kubitalnyy code ♀V individual group's ♂K significantly superior bees ♀K group's ♂V. Compared to the parent form these signs in hybrid bees of both groups occupy an intermediate position. Dominated on these grounds bees Vuchkivskoho type. For the length and width of the wing reliable working individuals had the advantage of females Vuchkivskyy type, paired with Kolochavskyy type drones and bees reciprocal combination took an intermediate position between paternal and maternal forms of wing length and width yielded all forms. Analysis of some patterns and mechanisms of heterosis for the purpose of breeding and maximize production. The value of all investigated exterior traits worker bees in family research groups to meet the requirements of the standard for biomorphological Carpathian breed bees.Отримано нові селекційні досягнення у бджільництві. У процесі дослідження та аналізу літературних джерел по гібридизації у бджільництві обґрунтована доцільність чистопородного розведення бджіл та використання міжлінійних та міжтипових внутрішньопородних гібридів, які по продуктивності мало поступаються міжпородним, але мають дуже суттєву перевагу, адже зберігається чистота породи. Встановлено, що за ознаками, які характеризують розміри черевця бджіл, довжину хоботка і кубітальний індекс, особини групи ♀В х ♂К достовірно переважали бджіл групи ♀К х ♂В. Порівняно з батьківськими формами, ці ознаки у гібридних бджіл обох груп займали проміжне положення. Переважали за цими ознаками бджоли Вучківського типу. За довжиною і шириною крила достовірну перевагу мали робочі особини від маток типу Вучківський, спарованих із трутнями типу Колочавський, а бджоли реципрокного поєднання займали проміжне положення між батьківською і материнською формами за довжиною крила, а за шириною поступалися всім формам. Проаналізовано деякі закономірності і механізми гетерозису з метою розведення і отримання максимальної кількості продукції. Значення всіх досліджуваних екстер’єрних ознак робочих бджіл у родин дослідних груп відповідали вимогам біоморфологічного стандарту для карпатської породи бджіл

Performance improvement by temperature control of an open-cathode PEM fuel cell system

The work presented in this article combines experimental analysis and theoretical studies of temperature effects on the performance of an open-cathode, self-humidified PEM fuel cell system for the design of optimal control strategies. The experimental analysis shows the great potential of improving the system performance by proper thermal management. The most significant temperature dependent parameter of the system under study is the exchange current density. On the one hand it is influenced positively by a temperature increase as this lowers the activation barrier. On the other hand a higher temperature causes a reduction of the electrochemical active sites in the cathode catalyst layer (CCL) due to lower water content in the ionomer and primary pores. Dynamic models for fuel cell temperature, liquid water transport and the related electrochemistry have been developed and validated against the experiment. A cascaded Extremum Seeking control algorithm with a local PI controller is proposed to regulate the temperature to a fuel cell voltage maximum. However, the slow dynamics of the temperature related catalyst-drying effect on performance complicate the optimal thermal management with model-free control strategies.Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señale

Overexpression of the UGT73C6 alters brassinosteroid glucoside formation in Arabidopsis thaliana

<p>Abstract</p> <p>Background</p> <p>Brassinosteroids (BRs) are signaling molecules that play essential roles in the spatial regulation of plant growth and development. In contrast to other plant hormones BRs act locally, close to the sites of their synthesis, and thus homeostatic mechanisms must operate at the cellular level to equilibrate BR concentrations. Whilst it is recognized that levels of bioactive BRs are likely adjusted by controlling the relative rates of biosynthesis and by catabolism, few factors, which participate in these regulatory events, have as yet been identified. Previously we have shown that the UDP-glycosyltransferase UGT73C5 of <it>Arabidopsis thaliana </it>catalyzes 23-<it>O</it>-glucosylation of BRs and that glucosylation renders BRs inactive. This study identifies the closest homologue of UGT73C5, UGT73C6, as an enzyme that is also able to glucosylate BRs <it>in planta</it>.</p> <p>Results</p> <p>In a candidate gene approach, in which homologues of UGT73C5 were screened for their potential to induce BR deficiency when over-expressed in plants, UGT73C6 was identified as an enzyme that can glucosylate the BRs CS and BL at their 23-<it>O</it>-positions <it>in planta</it>. GUS reporter analysis indicates that <it>UGT73C6 </it>shows over-lapping, but also distinct expression patterns with <it>UGT73C5 </it>and YFP reporter data suggests that at the cellular level, both UGTs localize to the cytoplasm and to the nucleus. A liquid chromatography high-resolution mass spectrometry method for BR metabolite analysis was developed and applied to determine the kinetics of formation and the catabolic fate of BR-23-<it>O</it>-glucosides in wild type and <it>UGT73C5 </it>and <it>UGT73C6 </it>over-expression lines. This approach identified novel BR catabolites, which are considered to be BR-malonylglucosides, and provided first evidence indicating that glucosylation protects BRs from cellular removal. The physiological significance of BR glucosylation, and the possible role of UGT73C6 as a regulatory factor in this process are discussed in light of the results presented.</p> <p>Conclusion</p> <p>The present study generates essential knowledge and molecular and biochemical tools, that will allow for the verification of a potential physiological role of UGT73C6 in BR glucosylation and will facilitate the investigation of the functional significance of BR glucoside formation in plants.</p

Diagnostic performance of tuberculosis-specific IgG antibody profiles in patients with presumptive tuberculosis from two continents

Background. Development of rapid diagnostic tests for tuberculosis is a global priority. A  whole proteome screen identified Mycobacterium tuberculosis antigens associated with serological responses in tuberculosis patients. We used World Health Organization (WHO) target product profile (TPP) criteria for a detection test and triage test to evaluate these antigens. Methods. Consecutive patients presenting to microscopy centers and district hospitals in Peru and to outpatient clinics at a tuberculosis reference center in Vietnam were recruited. We tested blood samples from 755 HIV–uninfected adults with presumptive pulmonary tuberculosis to measure IgG antibody responses to 57 M. tuberculosis antigens using a field-based multiplexed serological assay and a 132-antigen bead-based reference assay. We evaluated single antigen performance and models of all possible 3-antigen combinations and multiantigen combinations. Results. Three-antigen and multiantigen models performed similarly and were superior to single antigens. With specificity set at 90% for a detection test, the best sensitivity of a 3-antigen model was 35% (95% confidence interval [CI], 31–40). With sensitivity set at 85% for a triage test, the specificity of the best 3-antigen model was 34% (95% CI, 29–40). The reference assay also did not meet study targets. Antigen performance differed significantly between the study sites for 7/22 of the best-performing antigens. Conclusions. Although M. tuberculosis antigens were recognized by the IgG response during tuberculosis, no single antigen or multiantigen set performance approached WHO TPP criteria for clinical utility among HIV-uninfected adults with presumed tuberculosis in high-volume, urban settings in tuberculosis-endemic countries

Aptamer-based multiplexed proteomic technology for biomarker discovery

Interrogation of the human proteome in a highly multiplexed and efficient manner remains a coveted and challenging goal in biology. We present a new aptamer-based proteomic technology for biomarker discovery capable of simultaneously measuring thousands of proteins from small sample volumes (15 [mu]L of serum or plasma). Our current assay allows us to measure ~800 proteins with very low limits of detection (1 pM average), 7 logs of overall dynamic range, and 5% average coefficient of variation. This technology is enabled by a new generation of aptamers that contain chemically modified nucleotides, which greatly expand the physicochemical diversity of the large randomized nucleic acid libraries from which the aptamers are selected. Proteins in complex matrices such as plasma are measured with a process that transforms a signature of protein concentrations into a corresponding DNA aptamer concentration signature, which is then quantified with a DNA microarray. In essence, our assay takes advantage of the dual nature of aptamers as both folded binding entities with defined shapes and unique sequences recognizable by specific hybridization probes. To demonstrate the utility of our proteomics biomarker discovery technology, we applied it to a clinical study of chronic kidney disease (CKD). We identified two well known CKD biomarkers as well as an additional 58 potential CKD biomarkers. These results demonstrate the potential utility of our technology to discover unique protein signatures characteristic of various disease states. More generally, we describe a versatile and powerful tool that allows large-scale comparison of proteome profiles among discrete populations. This unbiased and highly multiplexed search engine will enable the discovery of novel biomarkers in a manner that is unencumbered by our incomplete knowledge of biology, thereby helping to advance the next generation of evidence-based medicine

Evaluation of the MOCAGE Chemistry Transport Model during the ICARTT/ITOP Experiment

We evaluate the Meteo-France global chemistry transport 3D model MOCAGE (MOdele de Chimie Atmospherique a Grande Echelle) using the important set of aircraft measurements collected during the ICARRT/ITOP experiment. This experiment took place between US and Europe during summer 2004 (July 15-August 15). Four aircraft were involved in this experiment providing a wealth of chemical data in a large area including the North East of US and western Europe. The model outputs are compared to the following species of which concentration is measured by the aircraft: OH, H2O2, CO, NO, NO2, PAN, HNO3, isoprene, ethane, HCHO and O3. Moreover, to complete this evaluation at larger scale, we used also satellite data such as SCIAMACHY NO2 and MOPITT CO. Interestingly, the comprehensive dataset allowed us to evaluate separately the model representation of emissions, transport and chemical processes. Using a daily emission source of biomass burning, we obtain a very good agreement for CO while the evaluation of NO2 points out incertainties resulting from inaccurate ratio of emission factors of NOx/CO. Moreover, the chemical behavior of O3 is satisfactory as discussed in the paper