98 research outputs found

    An improved optimization technique for estimation of solar photovoltaic parameters

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    The nonlinear current vs voltage (I-V) characteristics of solar PV make its modelling difficult. Optimization techniques are the best tool for identifying the parameters of nonlinear models. Even though, there are different optimization techniques used for parameter estimation of solar PV, still the best optimized results are not achieved to date. In this paper, Wind Driven Optimization (WDO) technique is proposed as the new method for identifying the parameters of solar PV. The accuracy and convergence time of the proposed method is compared with results of Pattern Search (PS), Genetic Algorithm (GA), and Simulated Annealing (SA) for single diode and double diode models of solar PV. Furthermore, for performance validation, the parameters obtained through WDO are compared with hybrid Bee Pollinator Flower Pollination Algorithm (BPFPA), Flower Pollination Algorithm (FPA), Generalized Oppositional Teaching Learning Based Optimization (GOTLBO), Artificial Bee Swarm Optimization (ABSO), and Harmony Search (HS). The obtained results clearly reveal that WDO algorithm can provide accurate optimized values with less number of iterations at different environmental conditions. Therefore, the WDO can be recommended as the best optimization algorithm for parameter estimation of solar PV

    GPCALMA: A Tool For Mammography With A GRID-Connected Distributed Database

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    The GPCALMA (Grid Platform for Computer Assisted Library for MAmmography) collaboration involves several departments of physics, INFN sections, and italian hospitals. The aim of this collaboration is developing a tool that can help radiologists in early detection of breast cancer. GPCALMA has built a large distributed database of digitised mammographic images (about 5500 images corresponding to 1650 patients) and developed a CAD (Computer Aided Detection) software which is integrated in a station that can also be used for acquire new images, as archive and to perform statistical analysis. The images are completely described: pathological ones have a consistent characterization with radiologist's diagnosis and histological data, non pathological ones correspond to patients with a follow up at least three years. The distributed database is realized throught the connection of all the hospitals and research centers in GRID tecnology. In each hospital local patients digital images are stored in the local database. Using GRID connection, GPCALMA will allow each node to work on distributed database data as well as local database data. Using its database the GPCALMA tools perform several analysis. A texture analysis, i.e. an automated classification on adipose, dense or glandular texture, can be provided by the system. GPCALMA software also allows classification of pathological features, in particular massive lesions analysis and microcalcification clusters analysis. The performance of the GPCALMA system will be presented in terms of the ROC (Receiver Operating Characteristic) curves. The results of GPCALMA system as "second reader" will also be presented.Comment: 6 pages, Proceedings of the Seventh Mexican Symposium on Medical Physics 2003, Vol. 682/1, pp. 67-72, Mexico City, Mexic

    Cannabis oil: Effects on Cannabinoid-Induced Tetrad, blood pressure and metabolic parameters in female rats fed a sucrose-rich diet

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    Metabolic Syndrome (MS) is one of the most commonly used names for a clinical entity that brings together or associates different disorders that increase the risk of cardiovascular disease. Cannabis sativa has been used as an herbal medicine for tens of centuries. This study aimed to analyze the effects of cannabis oil administration on cannabinoid-induced tetrad, systolic and diastolic blood pressure, and metabolic parameters in normal female rats fed a sucrose-rich diet (SRD). Female Wistar rats were fed with the one of following diets for 21 days: Reference Diet (RD): standard commercial laboratory diet, SRD, and SRD+Cannabis oil (SRD+Ca): oral administration of 1 mg/kg body weight of cannabis oil daily. The full spectrum cannabis oil contains a total cannabinoid CBD:THC 2:1 ratio. Cannabis oil administration in the SRD significantly increased analgesia and decreased locomotion. Systolic and diastolic blood pressures decreased during the experimental protocol. In the SRD+Ca group, serum triglyceride levels decreased significantly, without changes in cholesterol and glucose levels. In addition, serum uric acid, AST, ALT and AP levels were significantly decreased. In the liver, the abnormalities of the histological sections observed in the SRD group and triglycerides and cholesterol content improved remarkably with the cannabis oil administration. Our results suggest that the administration of full-spectrum cannabis oil, could be useful as a strategy to prevent some of the alterations present in MS, including hypertension, dyslipidemia, and liver damage. Furthermore, the analgesic effect of cannabis oil could be observed in female rats fed an SRD.Centro de InvestigaciĂłn y Desarrollo en CriotecnologĂ­a de Alimento

    La nécropole néolithique de la Feixa del Moro (Juberri, Andorre): Examen et nouvelles données

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    At the beginning of the 1980s, a series of archaeological interventions carried out by what was previously called the 'Servei d'Investigacions Arqueológiques del Patrimoni Artistic Nacional d'Andorra' in a Pyrenean valley in Andorra allowed the investigation of the Feixa del Moro site. In a high-altitude area below a series of abandoned terraces, several dwellings and burial structures were located, all of them with chronologies ranging between the Early and the Middle Neolithic (from the mid 5th millennium to the early 4th millennium cal. BC). The distinctiveness of this site does not only lie in its geographical location, nor in the kind of structures discovered, but also in the very good state of preservation of the human bone material recovered from the burials, making Feixa del Moro one of the reference sites for the Neolithic in the Pyrenees and, in general, the Western Mediterranean. So far, sites with a similar conservation of both bones and burial structures are really uncommon. Moreover, the concentration in so small an area, and in the same stratigraphic unit, of such a diversity of evidence, including burials, silos and hearths, is yet more unusual. There are no similar sites in Andorra, or even in the entire Pyrenees. The only other burial site of comparable chronology discovered in the area is the Segudet site, and only a few high-altitude Neolithic dwelling sites are known. Even if cist burials are quite common in the northeast of the Iberian Peninsula and in Southern France, Feixa del Moro is the first that has been found at high altitude. The archaeological work undertaken between 1983 and 1985 provided a picture of a farming community belonging to the so-called 'Sepulcros de fosa' Culture, established in the very heart of the Pyrenees and, thus, highlighted the complexity of Neolithic settlement patterns, even in mountainous zones. At the same time, several analyses of the archaeological materials were already carried out, making Feixa del Moro a reference site for archaeological research even now. Nevertheless, three decades later, new methodologies and the technical advances available are allowing archaeologists to refine old interpretations, to reopen old debates and to carry out new analyses that can improve our understanding of the past. In this respect, since 2011, within the research project 'Aproximación a las primeras comunidades neolíticas del NE peninsular a través de sus pråcticas funerarias' (HAR2011-23149), funded by the Spanish Ministry for the Economy and Competitiveness, a group of interdisciplinary researchers have begun to study several Neolithic burial contexts in the northeast of the Iberian Peninsula, among which Feixa del Moro. Following this perspective, in this paper, we present the outcome of the new analyses carried out on the burial goods and of the biochemistry and radiocarbon analyses carried out on the human bone material from the three cist burials of Feixa del Moro, with the aim of better understanding the early farming communities who settled in the Pyrenees. Since the last archaeological work carried out in the 1990s, large quantities of data have been lost. This has produced a certain degree of confusion and misunderstanding that has been repeated in other studies undertaken a posteriori on the site by other scholars. Some of these interpretations need to be revised. That it is why, within the current research project, we are not only bringing in new analyses, but also re-examining all the old written and graphic information available, as well as the state of the conserved archaeological material. The data presented in this paper resume all the available information on the Feixa del Moro site, correcting old mistakes and bias, updating the 1980s archaeological registers and presenting new analyses as well. Our aim is to ensure that Feixa del Moro remains a reference site for the Pyrenean and Western Mediterranean Neolithic. At the same time, we wish to encourage other researchers to undertake new analyses and to embrace new perspectives in order to improve our understanding of Neolithic societies

    GPCALMA, a mammographic CAD in a GRID connection

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    6 pages, 4 figures, to appear in CARS 2003 Proceedings, Computer Assisted Radiology and Surgery 17th International Congress and Exhibition, London, June 25-28, 2003Purpose of this work is the development of an automatic system which could be useful for radiologists in the investigation of breast cancer. A breast neoplasia is often marked by the presence of microcalcifications and massive lesions in the mammogram: hence the need for tools able to recognize such lesions at an early stage. GPCALMA (Grid Platform Computer Assisted Library for MAmmography), a collaboration among italian physicists and radiologists, has built a large distributed database of digitized mammographic images (at this moment about 5500 images corresponding to 1650 patients). This collaboration has developed a CAD (Computer Aided Detection) system which, installed in an integrated station, can also be used for digitization, as archive and to perform statistical analysis. With a GRID configuration it would be possible for the clinicians tele- and co-working in new and innovative groupings ('virtual organisations') and, using the whole database, by the GPCALMA tools several analysis can be performed. Furthermore the GPCALMA system allows to be abreast of the CAD technical progressing into several hospital locations always with remote working by GRID connection. We report in this work the results obtained by the GPCALMA CAD software implemented with a GRID connection

    Role of age and comorbidities in mortality of patients with infective endocarditis

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    Purpose: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. Methods: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015. Patients were stratified into three age groups:<65 years, 65 to 80 years, and = 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. Results: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 = 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients =80 years who underwent surgery were significantly lower compared with other age groups (14.3%, 65 years; 20.5%, 65-79 years; 31.3%, =80 years). In-hospital mortality was lower in the <65-year group (20.3%, <65 years;30.1%, 65-79 years;34.7%, =80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%, =80 years; p = 0.003).Independent predictors of mortality were age = 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI = 3 (HR:1.62; 95% CI:1.39–1.88), and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared, the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. Conclusion: There were no differences in the clinical presentation of IE between the groups. Age = 80 years, high comorbidity (measured by CCI), and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    The LHCb upgrade I

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    The LHCb upgrade represents a major change of the experiment. The detectors have been almost completely renewed to allow running at an instantaneous luminosity five times larger than that of the previous running periods. Readout of all detectors into an all-software trigger is central to the new design, facilitating the reconstruction of events at the maximum LHC interaction rate, and their selection in real time. The experiment's tracking system has been completely upgraded with a new pixel vertex detector, a silicon tracker upstream of the dipole magnet and three scintillating fibre tracking stations downstream of the magnet. The whole photon detection system of the RICH detectors has been renewed and the readout electronics of the calorimeter and muon systems have been fully overhauled. The first stage of the all-software trigger is implemented on a GPU farm. The output of the trigger provides a combination of totally reconstructed physics objects, such as tracks and vertices, ready for final analysis, and of entire events which need further offline reprocessing. This scheme required a complete revision of the computing model and rewriting of the experiment's software

    Measurement of CP asymmetries and branching fraction ratios of B− decays to two charm mesons

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    The CPCP asymmetries of seven B−B^- decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9fb−19\text{fb}^{-1} of proton-proton collisions collected by the LHCb experiment. Decays involving a D∗0D^{*0} or Ds∗−D^{*-}_s meson are analysed by reconstructing only the D0D^0 or Ds−D^-_s decay products. This paper presents the first measurement of ACP(B−→Ds∗−D0)\mathcal{A}^{CP}(B^- \rightarrow D^{*-}_s D^0) and ACP(B−→Ds−D∗0)\mathcal{A}^{CP}(B^- \rightarrow D^{-}_s D^{*0}), and the most precise measurement of the other five CPCP asymmetries. There is no evidence of CPCP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.The CP asymmetries of seven B−^{−} decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9 fb−1^{−1} of proton-proton collisions collected by the LHCb experiment. Decays involving a D∗0^{*0} or Ds∗− {D}_s^{\ast -} meson are analysed by reconstructing only the D0^{0} or Ds− {D}_s^{-} decay products. This paper presents the first measurement of ACP \mathcal{A} ^{CP}(B−^{−}→Ds∗− {D}_s^{\ast -} D0^{0}) and ACP \mathcal{A} ^{CP}(B−^{−}→Ds− {D}_s^{-} D∗0^{∗0}), and the most precise measurement of the other five CP asymmetries. There is no evidence of CP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured.[graphic not available: see fulltext]The CPCP asymmetries of seven B−B^- decays to two charm mesons are measured using data corresponding to an integrated luminosity of 9 fb−19\text{ fb}^{-1} of proton-proton collisions collected by the LHCb experiment. Decays involving a D∗0D^{*0} or Ds∗−D^{*-}_s meson are analysed by reconstructing only the D0D^0 or Ds−D^-_s decay products. This paper presents the first measurement of ACP(B−→Ds∗−D0)\mathcal{A}^{CP}(B^- \rightarrow D^{*-}_s D^0) and ACP(B−→Ds−D∗0)\mathcal{A}^{CP}(B^- \rightarrow D^{-}_s D^{*0}), and the most precise measurement of the other five CPCP asymmetries. There is no evidence of CPCP violation in any of the analysed decays. Additionally, two ratios between branching fractions of selected decays are measured
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