The Iterative Signature Algorithm for the analysis of large scale gene expression data

We present a new approach for the analysis of genome-wide expression data. Our method is designed to overcome the limitations of traditional techniques, when applied to large-scale data. Rather than alloting each gene to a single cluster, we assign both genes and conditions to context-dependent and potentially overlapping transcription modules. We provide a rigorous definition of a transcription module as the object to be retrieved from the expression data. An efficient algorithm, that searches for the modules encoded in the data by iteratively refining sets of genes and conditions until they match this definition, is established. Each iteration involves a linear map, induced by the normalized expression matrix, followed by the application of a threshold function. We argue that our method is in fact a generalization of Singular Value Decomposition, which corresponds to the special case where no threshold is applied. We show analytically that for noisy expression data our approach leads to better classification due to the implementation of the threshold. This result is confirmed by numerical analyses based on in-silico expression data. We discuss briefly results obtained by applying our algorithm to expression data from the yeast S. cerevisiae.Comment: Latex, 36 pages, 8 figure

Experimental Test of a Two-dimensional Approximation for Dielectric Microcavities

Open dielectric resonators of different shapes are widely used for the manufacture of microlasers. A precise determination of their resonance frequencies and widths is crucial for their design. Most microlasers have a flat cylindrical geometry, and a two-dimensional approximation, the so-called method of the effective index of refraction, is commonly employed for numerical calculations. Our aim has been an experimental test of the precision and applicability of a model based on this approximation. We performed very thorough and accurate measurements of the resonance frequencies and widths of two passive circular dielectric microwave resonators and found significant deviations from the model predictions. From this we conclude that the model generally fails in the quantitative description of three-dimensional dielectric resonators.Comment: 10 pages, 13 figure

The eventization of leisure and the strange death of alternative Leeds

The communicative potential of city spaces as leisure spaces is a central assumption of political activism and the creation of alternative, counter-cultural and subcultural scenes. However, such potential for city spaces is limited by the gentrification, privatization and eventization of city centres in the wake of wider societal and cultural struggles over leisure, work and identity formation. In this paper, we present research on alternative scenes in the city of Leeds to argue that the eventization of the city centre has led to a marginalization and of alternative scenes on the fringes of the city. Such marginalization has not caused the death of alternative Leeds or political activism associated with those scenes—but it has changed the leisure spaces (physical, political and social) in which alternative scenes contest the mainstream

Ahorro energético en el consumo de gas residencial mediante aislamiento térmico en la construcción

Se determinaron los coeficientes volumétricos de pérdidas de calor, tanto en una vivienda “tipo casa” como en otra “tipo edificio”, considerando tres sistemas constructivos diferentes utilizados frecuentemente en el país. Se verificaron luego éstos mismos, pero aislando el techo y los muros con 3” y 2” respectivamente, de un aislante térmico convencional de conductividad media. Además, se cambiaron las carpinterías de vidrio simple por doble vidriado hermético. La tipología utilizada es una vivienda de 3 ambientes de aproximadamente 60 m² de superficie; obtenida como promedio de datos del Censo 2001, como así también de las cantidades de viviendas tipo “Hogares Casas” y tipo “Hogares Departamentos” relevados en cada Provincia. La demanda de gas en millones de m³ por día, destinada a calefacción para uso residencial y la cantidad de usuarios registrados, correspondientes al año 2006, fueron recabadas de ENARGAS. Como resultado, se estimó un ahorro de aproximadamente 40% aislando muros y techos; valor que puede superar el 50% si también se emplea doble vidriado hermético en las carpinterías.Volumetric heat loss coefficient was determined not only for a detached house but also for a unit in an apartment building. Three different construction systems usually used in our country were considered. Then, the same construction systems with added conventional 3” roof insulation and 2” wall insulation of medium thermal conductivity were analyzed. In addition, single glazing windows were changed for insulated double glazing ones. The pattern is a housing consisting of three rooms about 60 m² obtained as average from Census 2001 data, as well as the amount of single-unit and multi-unit dwellings taken form data of each Province. Daily gas demand for residential use, in millions of m³, and amount of registered users, were obtained from ENARGAS during 2006. As a result, savings of about 40% were obtained by roof and wall insulation; this value may exceed 50% if insulated double glazing windows are used.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Ahorro energético en el consumo de gas residencial mediante aislamiento térmico en la construcción

Se determinaron los coeficientes volumétricos de pérdidas de calor, tanto en una vivienda “tipo casa” como en otra “tipo edificio”, considerando tres sistemas constructivos diferentes utilizados frecuentemente en el país. Se verificaron luego éstos mismos, pero aislando el techo y los muros con 3” y 2” respectivamente, de un aislante térmico convencional de conductividad media. Además, se cambiaron las carpinterías de vidrio simple por doble vidriado hermético. La tipología utilizada es una vivienda de 3 ambientes de aproximadamente 60 m² de superficie; obtenida como promedio de datos del Censo 2001, como así también de las cantidades de viviendas tipo “Hogares Casas” y tipo “Hogares Departamentos” relevados en cada Provincia. La demanda de gas en millones de m³ por día, destinada a calefacción para uso residencial y la cantidad de usuarios registrados, correspondientes al año 2006, fueron recabadas de ENARGAS. Como resultado, se estimó un ahorro de aproximadamente 40% aislando muros y techos; valor que puede superar el 50% si también se emplea doble vidriado hermético en las carpinterías.Volumetric heat loss coefficient was determined not only for a detached house but also for a unit in an apartment building. Three different construction systems usually used in our country were considered. Then, the same construction systems with added conventional 3” roof insulation and 2” wall insulation of medium thermal conductivity were analyzed. In addition, single glazing windows were changed for insulated double glazing ones. The pattern is a housing consisting of three rooms about 60 m² obtained as average from Census 2001 data, as well as the amount of single-unit and multi-unit dwellings taken form data of each Province. Daily gas demand for residential use, in millions of m³, and amount of registered users, were obtained from ENARGAS during 2006. As a result, savings of about 40% were obtained by roof and wall insulation; this value may exceed 50% if insulated double glazing windows are used.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Small whole heart volume predicts cardiovascular events in patients with stable chest pain: insights from the PROMISE trial

Objectives The size of the heart may predict major cardiovascular events (MACE) in patients with stable chest pain. We aimed to evaluate the prognostic value of 3D whole heart volume (WHV) derived from non-contrast cardiac computed tomography (CT). Methods Among participants randomized to the CT arm of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE), we used deep learning to extract WHV, defined as the volume of the pericardial sac. We compared the WHV across categories of cardiovascular risk factors and coronary artery disease (CAD) characteristics and determined the association of WHV with MACE (all-cause death, myocardial infarction, unstable angina; median follow-up: 26 months). Results In the 3798 included patients (60.5 +/- 8.2 years; 51.5% women), the WHV was 351.9 +/- 57.6 cm(3)/m(2). We found smaller WHV in no- or non-obstructive CAD, women, people with diabetes, sedentary lifestyle, and metabolic syndrome. Larger WHV was found in obstructive CAD, men, and increased atherosclerosis cardiovascular disease (ASCVD) risk score (p < 0.05). In a time-to-event analysis, small WHV was associated with over 4.4-fold risk of MACE (HR (per one standard deviation) = 0.221; 95% CI: 0.068-0.721; p = 0.012) independent of ASCVD risk score and CT-derived CAD characteristics. In patients with non-obstructive CAD, but not in those with no- or obstructive CAD, WHV increased the discriminatory capacity of ASCVD and CT-derived CAD characteristics significantly. Conclusions Small WHV may represent a novel imaging marker of MACE in stable chest pain. In particular, WHV may improve risk stratification in patients with non-obstructive CAD, a cohort with an unmet need for better risk stratification

Update of Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias (International Endohernia Society (IEHS)) : Part B

In 2014 the International Endohernia Society (IEHS) published the first international "Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias". Guidelines reflect the currently best available evidence in diagnostics and therapy and give recommendations to help surgeons to standardize their techniques and to improve their results. However, science is a dynamic field which is continuously developing. Therefore, guidelines require regular updates to keep pace with the evolving literature. Methods For the development of the original guidelines all relevant literature published up to year 2012 was analyzed using the ranking of the Oxford Centre for Evidence-Based-Medicine. For the present update all of the previous authors were asked to evaluate the literature published during the recent years from 2012 to 2017 and revise their statements and recommendations given in the initial guidelines accordingly. In two Consensus Conferences (October 2017 Beijing, March 2018 Cologne) the updates were presented, discussed, and confirmed. To avoid redundancy, only new statements or recommendations are included in this paper. Therefore, for full understanding both of the guidelines, the original and the current, must be read. In addition, the new developments in repair of abdominal wall hernias like surgical techniques within the abdominal wall, release operations (transversus muscle release, component separation), Botox application, and robot-assisted repair methods were included. Results Due to an increase of the number of patients and further development of surgical techniques, repair of primary and secondary abdominal wall hernias attracts increasing interests of many surgeons. Whereas up to three decades ago hernia-related publications did not exceed 20 per year, currently this number is about 10-fold higher. Recent years are characterized by the advent of new techniques-minimal invasive techniques using robotics and laparoscopy, totally extraperitoneal repairs, novel myofascial release techniques for optimal closure of large defects, and Botox for relaxing the abdominal wall. Furthermore, a concomitant rectus diastasis was recognized as a significant risk factor for recurrence. Despite still insufficient evidence with respect to these new techniques it seemed to us necessary to include them in the update to stimulate surgeons to do research in these fields. Conclusion Guidelines are recommendations based on best available evidence intended to help the surgeon to improve the quality of his daily work. However, science is a continuously evolving process, and as such guidelines should be updated about every 3 years. For a comprehensive reference, however, it is suggested to read both the initially guidelines published in 2014 together with the update. Moreover, the presented update includes also techniques which were not known 3 years before

Casimir effect: running Newton constant or cosmological term

We argue that the instability of Euclidean Einstein gravity is an indication that the vacuum is non perturbative and contains a condensate of the metric tensor in a manner reminiscent of Yang-Mills theories. As a simple step toward the characterization of such a vacuum the value of the one-loop effective action is computed for Euclidean de Sitter spaces as a function of the curvature when the unstable conformal modes are held fixed. Two phases are found, one where the curvature is large and gravitons should be confined and another one which appears to be weakly coupled and tends to be flat. The induced cosmological constant is positive or negative in the strongly or weakly curved phase, respectively. The relevance of the Casimir effect in understanding the UV sensitivity of gravity is pointed out.Comment: Final, slightly extended version, to appear in Classical and Quantum Gravit