1,207 research outputs found
Optimal household energy management and participation in ancillary services with PV production
The work presented in this paper deals with a project aiming to increase the value of photovoltaic (PV) solar production for residential application. To contribute to the development of the new functionalities for such system and the efficient control system to optimize its operation, this paper defines the possibility for the proposed system to participate to the ancillary services, particularly in active power service provider. This service of PV-based system for housing application, as it does not exist today, has led to a market design proposition in the distribution system. The mathematical model for calculating the optimal operation of system (sources, load, and the exchange power with the grid) results in a linear mix integer optimization problem where the objective is to maximize the profit obtained by participating to electricity market. The approach is illustrated in an example study case. The PV producer could benefit from its intervention on balancing market or ancillary services market despite of the impact on the profit of several kinds of uncertainty, as the intermittence of PV source.energy management ; ancillary services ; PV production ; household application
myGRN: a database and visualisation system for the storage and analysis of developmental genetic regulatory networks
<p>Abstract</p> <p>Background</p> <p>Biological processes are regulated by complex interactions between transcription factors and signalling molecules, collectively described as Genetic Regulatory Networks (GRNs). The characterisation of these networks to reveal regulatory mechanisms is a long-term goal of many laboratories. However compiling, visualising and interacting with such networks is non-trivial. Current tools and databases typically focus on GRNs within simple, single celled organisms. However, data is available within the literature describing regulatory interactions in multi-cellular organisms, although not in any systematic form. This is particularly true within the field of developmental biology, where regulatory interactions should also be tagged with information about the time and anatomical location of development in which they occur.</p> <p>Description</p> <p>We have developed myGRN (<url>http://www.myGRN.org</url>), a web application for storing and interrogating interaction data, with an emphasis on developmental processes. Users can submit interaction and gene expression data, either curated from published sources or derived from their own unpublished data. All interactions associated with publications are publicly visible, and unpublished interactions can only be shared between collaborating labs prior to publication. Users can group interactions into discrete networks based on specific biological processes. Various filters allow dynamic production of network diagrams based on a range of information including tissue location, developmental stage or basic topology. Individual networks can be viewed using myGRV, a tool focused on displaying developmental networks, or exported in a range of formats compatible with third party tools. Networks can also be analysed for the presence of common network motifs. We demonstrate the capabilities of myGRN using a network of zebrafish interactions integrated with expression data from the zebrafish database, ZFIN.</p> <p>Conclusion</p> <p>Here we are launching myGRN as a community-based repository for interaction networks, with a specific focus on developmental networks. We plan to extend its functionality, as well as use it to study networks involved in embryonic development in the future.</p
Study on genetic diversity in Pakistani wheat varieties using simple sequence repeat (SSR) markers
Common wheat ( Triticum aestivum L.) is a grass species, cultivated world wide. Globally, it is the most important human food grain and ranks second in total production as a cereal crop behind maize. Genetic diversity evaluation of germplasm is the basis of improvement in wheat. In the present study genetic diversity of 10 varieties of wheat (T. aestivum) were analyzed using 14 simple sequence repeat (SSR) primer sets. To estimate the genetic diversity among the genotypes, bivariate data matrix was generated and genetic distances were calculated using unweighted pair group of arithmetic mean (UPGMA) procedure. A high degree of genetic polymorphism was observed among the wheat varieties with average genetic distances ranged from 16 to 67%. SSR primer gdm-3, gdm-19, gdm-61, gdm-62, gdm-64, gdm-86, gdm-88, gdm 93-2a, 93-4b, gdm-13 and gdm-115 amplified 3, 2.9, 4.1, 4.7, 3, 1.7, 2.7, 3.7, 5.8, 4.1 and 1.4 loci per variety, respectively. Most diverse varieties of wheat were identified (Punjab-81 and Indus-79) and recommendations were made to utilize these varieties in future breeding program
CuO Elaboration and Studies of the Influence of Heat Treatment on the Structural Properties
In the present work we synthesize nano powders of CuO by precipitation method, using CuCl2 as precursor. The obtained powder has undergone a heat treatment annealing 100°C, and 450°C. Structural analysis by X-Ray diffraction, Fourier transform infrared (FTIR) microscopy and scanning electron microscopy (SEM) reveal that CuO nano particles are in nano graphs forms and with improved crystallization at 450°C, annealing temperature as monoclinic crystal lattice structure. The radius of NCs calculated by the Scherrer formula is 12.31 nm
Phenotypic Type 2 Diabetes in Obese Youth: Insulin Sensitivity and Secretion in Islet Cell Antibody–Negative Versus –Positive Patients
OBJECTIVE— Some obese youth with a clinical diagnosis of type 2 diabetes have evidence of islet cell autoimmunity with positive autoantibodies. In this study, we investigated the differences in insulin sensitivity and secretion between autoantibody-negative (Ab−) and -positive (Ab+) youth with clinically diagnosed type 2 diabetes in comparison with control subjects
RESECTION OF RIGHT VENTRICULAR OUTFLOW TRACT PATCH DURING PULMONARY VALVE REPLACEMENT IMPROVES RIGHT VENTRICULAR VOLUMES AND EJECTION FRACTION IN PATIENTS WITH TETRALOGY OF FALLOT
Optimisation des Pertes par Commutation dans un Convertisseur Modulaire Multiniveaux (MMC)
International audienceLes pertes dans une liaison à courant continu àhaute tension sont un facteur pénalisant (4000 €/kW sur une duréede 30 ans). L’inconvénient vient des structures de type Onduleurde tension qui ont des pertes élevées (1.8%) relativement auxstructures à base de thyristors. L’arrivée des convertisseurs detype Modulaires Multiniveaux (MMC) a permis de réduire cespertes à 1%. Cet avantage permet d’envisager une forte utilisationde cette structure dans des applications HVDC. Le but de cetravail est d’étudier le contrôle bas niveau de ce convertisseur quicorrespond au choix des sous-modules à utiliser et à l’équilibragedes condensateurs afin de minimiser la fréquence de commutation.En se focalisant sur un contrôle de type ondulation des tensions dessous modules, une amélioration a été apportée via une réductionde la fréquence de commutation moyenne de ces sous-modules. Dessimulations sous MATLAB/Simulink ont été conduites et ontpermis de valider la méthode proposée
Optimal household energy management and economic analysis: from sizing to operation scheduling
The study presented in this paper takes part in a project aiming to increase the value of solar production for residential application with a medium-term vision where preferential solar energy subsidies will decrease before to disappear. This study is dedicated to propose and develop optimal energy architecture at supply side, a multi-source system based on photovoltaic (PV) solar energy connecting to main electrical network, taking further into account the effectiveness of intelligent demand side management. To investigate this issue, a method of optimal supplying system sizing and household energy management has been developed. This method, which has been formulated employing Mix Integer Linear Programming (MILP), enables the calculation of the appropriate configuration for power supply system and the optimal operation control to be applied. Using a Net Present Value (NPV) and Probability Index (P.I) basis, the economic analysis allows estimation of the viability of the proposed system under different factors of influence such as renewable energy policies, technology evolutions leading to cheaper installed PV module cost and deregulated electricity market. Simulation results show that, the solution makes it possible for PV power to be significantly valued by the customers without subsidized measures.connected-grid PV system ; battery storage ; sizing optimization ; energy management ; MILP
Pre-diabetes in overweight youth and early atherogenic risk
PURPOSE: To compare atherogenic lipoprotein particles and vascular smooth muscle biomarkers in overweight youth with pre-diabetes (PD) vs. normal glucose tolerance (NGT).
METHODS: 144 adolescents (60 black, 84 white; 102 female; PD=45, NGT=99) aged 10-19 years underwent a fasting blood draw and 2-h OGTT. Lipoprotein particle size and subclass concentration and vascular smooth muscle biomarkers (ICAM-1, VCAM-1 and E-selectin) were compared between youth with PD and NGT.
RESULTS: Compared with NGT, PD adolescents had smaller LDL (mean±SE: 20.5±0.1 vs. 21.0±0.1 nm; P=0.002) and HDL (8.62±0.05 vs. 8.85±0.04 nm; P=0.013) size and elevated medium small (159.2±10.3 vs. 123.8±6.4 nmol/L; P=0.037) and very small (626.3±45.4 vs. 458.5±26.4 nmol/L; P=0.032) LDL particle concentrations, after adjustment for race and BMI. Further adjusting for fasting insulin or visceral adiposity obviated these differences between the groups except for LDL size. ICAM-1 and E-selectin did not differ in youth with PD but correlated with LDL and HDL size, and small LDL particle concentrations.
CONCLUSIONS: Overweight adolescents with PD have an atherogenic lipoprotein profile of small LDL and HDL size and increased concentrations of small LDL, moderated by insulin resistance and visceral adiposity, but independently driven by dysglycemia for LDL size. Associations between smooth muscle biomarkers and lipoproteins could be an early signal heralding the atherogenic process. It remains to be determined if correction of dysglycemia and associated lipoprotein abnormalities in obese youth could prove effective in halting this process
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