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This paper highlights the initial findings of the European Commission funded project called MERGE (Mobile Energy Resources in Grids of Electricity). MERGE is a €4.5m, 16-partner collaborative research project supported by the European Commission’s Seventh Framework Programme (FP7). The consortium includes utilities, regulators, commercial organisations and universities with interests in the power generation, automotive, electronic commerce and hybrid and electric vehicle sectors across the entire European Union (EU). This major two-year research initiative began in January 2010. The MERGE project mission is to evaluate the impacts that electric vehicles (EV) will have on EU electric power systems with regards to planning, operation and market functioning. The focus is placed on EV and SmartGrid/MicroGrid simultaneous deployment, together with renewable energy increase, leading to CO2 emission reduction through the identification of enabling technologies and advanced control approaches.

In circuit simulators based on nodal analysis techniques, one numerical integration method is typically used to solve all differential equations. The properties of this method determine to a large extent the types of waveforms which can be simulated accurately. In this work, a concept for the position dependent control of numerical rotation to simulate waveforms with very diverse characteristics is introduced. The numerical integration is adjusted individually in different positions of the circuit so that an accurate emulation of diverse waveforms is attained. The object-oriented implementation is discussed. It is shown that the concept is numerically very efficient and therefore suitable for time critical simulation. Index Terms--Algorithms, circuit modeling; circuit simulation, electromagnetic transients, numerical integration, power system simulation.

This task force paper presents multi-domain tools and their interfacing issues to perform simulations that require expertise in multiple areas of physics, such as electrothermal, electromechanical, electrochemical, and electromagnetic simulations, etc. Features of single multi-domain simulation tools, which are capable of simulating more than one system such as electrical chemical, mechanical, etc., are discussed. In addition, programs that are not capable of performing multi-domain simulation independently but can be interfaced with other programs to perform multi-domain simulation are also covered. Two case studies are reported where multi-domain simulations are performed in offline and real-time environments through the interfacing of more than one simulation tool. [ABSTRACT FROM PUBLISHER]

Electric power distribution systems of many commercial and industrial sites often employ variable frequency drives and other loads that internally utilize dc. Such loads are often based on front-end line-commutated rectifiers. The detailed switch-level models of such rectifier systems can be readily implemented using a number of widely available digital programs and transient simulation tools, including the Electromagnetic Transient (EMT)-based programs and Matlab/Simulink. To improve the simulation efficiency for the system-level transient studies with a large number of such subsystems, the so-called dynamic average models have been utilized. This paper presents the average-value modeling methodologies for the conventional three-phase (six-pulse) front-end rectifier loads. We demonstrate the system operation and the dynamic performance of the developed average models in discontinuous and continuous modes, as well as under balanced and unbalanced operation. [ABSTRACT FROM PUBLISHER]

This paper extends the concept of dynamic average-value modeling to power-electronic-intensive hybrid-electric vehicular power trains. Hybrid vehicles with plug-in capability are becoming increasingly important in the study of emerging smart power grids, and their simulation using digital programs has gained widespread attention. This paper demonstrates the usefulness of averaging in preserving the dynamic characteristics of the vehicular system while reducing the computational intensity of its simulation on an Electromagnetic Transients Program-type simulator. This paper presents an example of averaging for modeling, simulation, and system-level studies of a power-split gear hybrid drive-train. [ABSTRACT FROM PUBLISHER]

This paper, prepared by a special task force of the IEEE PES Renewable Technologies Subcommittee, is a review of hybrid renewable/alternative energy (RE/AE) power generation systems focusing on energy sustainability. It highlights some important issues and challenges in the design and energy management of hybrid RE/AE systems. System configurations, generation unit sizing, storage needs, and energy management and control are addressed. Statistics on the current status and future trend of renewable power generation, as well as some critical challenges facing the widespread deployment of RE/AE power generation technologies and vision for future research in this area are also presented. The comprehensive list of references given at the end of the paper should be helpful to researchers working in this area. [ABSTRACT FROM PUBLISHER]

This paper deals with the current state-of-the-art in interfacing issues related to real-time digital simulators employed in the simulation of power systems and power-electronic systems. This paper provides an overview of technical challenges encountered and their solutions as the real-time digital simulators evolved. Hardware-in-the-loop interfacing for controller hardware and power apparatus hardware are also presented. [ABSTRACT FROM AUTHOR]

Die Untersuchung von Mammakarzinomen auf molekularer Ebene anhand der Expression bestimmter Genmuster lässt die Unterscheidung von 4 Gruppen zu: die Subtypen Luminal A und B, den HER2-Subtyp und den basalen Subtyp. Diese 4 Gruppen unterscheiden sich in ihrer Prognose sowie in ihrem Ansprechen auf spezifische Therapiemodalitäten. Auch die Entwicklung von Genexpressionsprofilen wie dem 21-Gen-Rückfallscore (Oncotype DX®) oder dem 70-Gen-Profil (Mammaprint®) kann einen Beitrag dazu leisten, adjuvante Therapien zielgerichteter einzusetzen. Die Chemotherapie ist ein integraler Bestandteil in der Systemtherapie des frühen Mammakarzinoms. Nachdem jedoch der Grossteil der Mammakarzinome östrogenrezeptorpositiv ist und potenziell geringer auf eine Chemotherapie anspricht, ist die Identifizierung derer, die von einer solchen Therapie profitieren, von besonderer Bedeutung. Die Analyse von Genexpressionsmustern kann dazu beitragen, das traditionelle histopathologische Staging zu ergänzen. Molecular staging of breast cancer with microarray technologies leads to different gene expression profiles distinguishing 4 special groups: luminal A and B subtype, HER2 subtype and basal subtype. These 4 groups show a different prognosis as well as different behaviours and responses to adjuvant therapy. The development of gene expression profiles to classify breast cancer may contribute to the targeted institution of adjuvant therapies. Especially the 21-gene recurrence score (Oncotype DX®) and the 70-gene profile (Mammaprint®) have become intensively examined prognostic and predictive tools. As chemotherapy is an integral component of adjuvant therapy in early breast cancer but estrogen-receptor-positive breast cancer is the most common type, patient selection for adjuvant chemotherapy is of particular interest. In instances when the benefit from chemotherapy seems modest, there is a decision making tool beside traditional histopathological parameters that might provide additional objective prognostic and predictive information. Those genomic decision making approaches may yield more rational treatment choices and may keep patients from systemic treatment modalities of lower value. Copyright © 2008 S. Karger AG, Basel L'examen des cancers du sein au niveau moléculaire par l'expression de certains patrons génétiques permet la distinction de 4 groupes: les sous-types luminal A et B, HER2 et basal. Ces 4 groupes se distinguent dans leur pronostic ainsi que leur réponse aux modalités thérapeutiques spécifiques. Le développement de profils d'expression génétique, p.ex. le score de récurrence de 21 gènes (Oncotype DX®) ou le profil de 70 gènes (Mammaprint®), peut contribuer à employer des thérapies adjuvantes mieux ciblées. La chimiothérapie est un élément intégral du traitement systémique du cancer du sein précoce. Mais comme la plus grande partie des carcinomes mammaires est positif pour le récepteur d'œstrogène et peut réagir plus faiblement à une chimiothérapie, il importe d'identifier les patientes qui pourraient profiter d'une telle thérapie. L'analyse des patrons d'expression génétique peut aider à compléter le staging histopathologique traditionnel. [ABSTRACT FROM AUTHOR]

The objective of this one-institutional study was to determine the number of large-core needle biopsies (LCNB), under three-dimensional ultrasound (3D-US) validation, that are sufficient to obtain a reliable histological diagnosis of a sonographically detectable breast lesion. Over an 28-month period, 962 sonographically guided LCNB were performed under 3D-US validation to assess 962 breast lesions. All biopsies were carried out with an automated core biopsy device fitted with 14-gauge (22 mm excursion) needles. Data of 962 biopsied breast lesions were gathered. Surgical follow-up was available for 659 lesions. Breast malignancies were diagnosed by ultrasound-guided LCNB with a sensitivity of 98.2% by performing three cores per lesion. In few cases, the open surgical specimen revealed the presence of invasive carcinomas in contrast to initial LNCB-based classification as ductal carcinomas in situ (DCIS, 11 lesions), lobular carcinoma in situ (one lesion), and atypical ductal hyperpasia (one lesion). Owing to disagreement between classification based on breast-imaging and histological findings, eight of these tumours were subsequently excised. Of the lesions that were removed at the patients' requests despite benign LCNB diagnosis, two were infiltrating carcinoma and one a DCIS. We demonstrate that three 3D-US-guided percutaneous core specimens are sufficient to achieve tissue for a reliable histological assessment of sonographically detectable breast lesions and allow the detection of malignancies with high sensitivity and low rate of false-negative diagnoses. [ABSTRACT FROM AUTHOR]

Today, many universities report record numbers of students enrolling in power and energy engineering courses. The power and energy industry shows strong interest in hiring qualified graduates, and the latter see exciting employment opportunities. Issues of power, energy, and environmental impact increasingly are at the center of interest at local conferences, are on the agenda of world summits, and are subject to active debate. The quest for effective and environmentally friendly solutions to energy problems stands at the forefront of a new era. The challenges involved call for an active interaction of university and industry in research and education, and this is the main subject of this article. The article is intended to give the reader an insight into existing forms of collaboration, to evaluate the benefits, and to discuss the trends of active interaction of university and industry in the diverse cultures of different countries. Typical mechanisms of collaboration are reviewed and the benefits resulting from collaboration for both industry and university are evaluated and elaborated upon. Based on these considerations, desirable features of university-industry collaboration today and in the future are discussed. [ABSTRACT FROM PUBLISHER]

Hermite polynomial chaos is used to create models of electric circuit branches for the study of random changes of parameters. The proposed method allows for seamless integration with nodal analysis. An analogy of Fourier series and Hermite polynomial chaos expansion is introduced to explain the methodology. Compared with root-sumsquare and Monte Carlo methods, the proposed method is shown to be fast and accurate. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to show differences between breast cancer patients < or =35 and >35 years with regard to tumor characteristics and to present the patient-relevant outcomes overall survival (OAS) and recurrence-free survival (RFS)., Methods: We analyzed data from 119 women aged 35 years or younger with breast cancer and compared multiple parameters against breast cancer patients between 36 and 55 (n = 1,097), all pre-menopausal. Data were adjusted for tumor characteristics and therapy., Results: There was no statistically significant difference in tumor size, axillary lymph node involvement, and histological subtypes. On the contrary, grading lymphovascular invasion and receptor negativity showed statistically significant differences. Unadjusted hazard ratio are 2.11 (1.32-3.39) (OAS) and 1.92 (1.35-2.73) (RFS). Multi-adjusted hazard ratio are 2.97 (1.70-5.18) (OAS) and 2.11 (1.42-3.13) (RFS)., Conclusions: In conclusion, young breast cancer patients still have a poor prognosis. Even after adjustment of the data, OAS and RFS showed a worse prognosis. Normal prognostic factors like tumor size, axillary lymph node involvement, and grading can therefore be not the explanation for the more aggressive disease progress within early onset breast cancer patients.

Background and Objective: Guidelines for the treatment of early-onset breast cancer have been proposed in several countries, but to date, their impact on outcomes is unverified. The objective of this study was to evaluate the association between guideline-adherent versus nonadherent treatment and recurrence-free survival (RFS) and overall survival (OAS) in early-onset breast cancer patients., Methods: A total of 1,778 patients were included in the study, of whom 111 were 35 years or younger and 1,667 were between 36 and 55 years. RFS and OAS were compared between the two groups, with respect to multiple parameters. All survival data were adjusted for tumor characteristics and analyzed with respect to guideline adherence according to the German Step 3 guidelines., Results: Statistically significant differences between the two groups (<35 years, 36-55 years) were observed with regard to breast surgery (p = 0.002) and hormone therapy (p = 0.006). Both groups were treated identically in terms of guideline adherence concerning axillary dissection (p = 0.9), radiation therapy (p = 0.7) and chemotherapy (p = 0.556). Young breast cancer patients whose treatment adhered to guideline recommendations had increased RFS and OAS [RFS: p = 0.030, hazard ratio (HR) 2.95, 95% confidence interval (CI) 1.11-7.83; OAS: p < or = 0.001, HR 2.92, 95% CI 2.01-4.23]., Conclusion: Guideline-adherent treatment for early-onset breast cancer patients significantly improves OAS and RFS and should therefore be demanded for all patients., (Copyright 2010 S. Karger AG, Basel.)

Molecular staging of breast cancer with microarray technologies leads to different gene expression profiles distinguishing 4 special groups: luminal A and B subtype, HER2 subtype and basal subtype. These 4 groups show a different prognosis as well as different behaviours and responses to adjuvant therapy. The development of gene expression profiles to classify breast cancer may contribute to the targeted institution of adjuvant therapies. Especially the 21-gene recurrence score (Oncotype DX) and the 70-gene profile (Mamma-print) have become intensively examined prognostic and predictive tools. As chemotherapy is an integral component of adjuvant therapy in early breast cancer but estrogen-receptor-positive breast cancer is the most common type, patient selection for adjuvant chemotherapy is of particular interest. In instances when the benefit from chemotherapy seems modest, there is a decision making tool beside traditional histopathological parameters that might provide additional objective prognostic and predictive information. Those genomic decision making approaches may yield more rational treatment choices and may keep patients from systemic treatment modalities of lower value., (Copyright 2008 S. Karger AG, Basel.)

Fetal magnetic resonance imaging (MRI) is a reliable method to further evaluate brain anomalies detected on ultrasonography. MRI can reveal additional brain abnormalities which are consequential for counselling parents about the fetal prognosis and subsequently influence the decision about continuing the pregnancy. In case of fatal malformations, MRI can confirm a diagnosis established on ultrasonography, supplying more reliability.

The ligands, receptors and related signaling proteins of the insulin-like growth factor family are involved in the regulation of breast-cancer cell growth. We investigated the expression pattern of insulin-like growth factor-I receptor (IGF-IR), insulin receptor (IR) and insulin receptor substrate-1 (IRS-1), a core downstream signaling protein, in 69 primary breast-cancer specimens of different grades and in 21 control tissues by immunohistochemistry. In addition, cell proliferation (percentage of Ki67(+) nuclei) and estrogen receptor (ER) expression were determined. IGF-IR, IRS-1 and IR were expressed mainly in epithelial cells. IRS-1 and IGF-IR were expressed at high levels in control tissues and in well and moderately differentiated carcinomas but at low levels in poorly differentiated breast cancers. IR expression did not show a significant correlation with the differentiation grade of the tissues investigated. Statistical analysis (ROC analysis for tumor grade) demonstrated that down-regulation of IGF-IR and IRS-1 correlated better with tumor progression than reduction of ER expression or increase in cell proliferation, IGF-IR showing the best correlation, followed by IRS-1 and, less significant, ER and Ki67. Our findings clearly show that progression of breast cancer is accompanied by a reduction of IGF-IR/IRS-1 expression and that IGF-IR/IRS-1 expression inversely correlates with high proliferation rate in dedifferentiated breast cancers. The strong correlation of IGF-IR and IRS-1 down-regulation with tumor progression suggests the use of IGF-IR and IRS-1 as a novel set of marker proteins for tumor grading., (Copyright 2000 Wiley-Liss, Inc.)

Operatively removed gallstones were examined on their surfaces and in fractured cross sections by incident light microscopy and scanning electron microscopy. In addition, micro-bore samples and X-ray crystallography were done. Five gallstone types consisting of three basic structural layers are differentiable by incident light microscopy. The three layers consist of a central nucleus which is always present, a radially structured middle layer, and a fine crystalline outer shell, the presence or absence of the latter two layers differentiating the stone types. Two crystal structures could be differentiated by electron microscopy; a flat and a globular type. The nucleus is always of the globular crystalline type, while the outer layers are flat crystalline. From this we were lead to believe that the conditions in vivo, under which the different layers of a gallstone are built, change. The micro-bore samples lead us to believe that calcium is only secondarily layed down in the gallstone framework. White crystalline deposits, which were formed several seconds after fracture, were discovered on the fractured gallstone cross sections.