Directed search for gravitational waves from Scorpius X-1 with initial LIGO data

We present results of a search for continuously emitted gravitational radiation, directed at the brightest low-mass x-ray binary, Scorpius X-1. Our semicoherent analysis covers 10 days of LIGO S5 data ranging from 50-550 Hz, and performs an incoherent sum of coherent F-statistic power distributed amongst frequency-modulated orbital sidebands. All candidates not removed at the veto stage were found to be consistent with noise at a 1% false alarm rate. We present Bayesian 95% confidence upper limits on gravitational-wave strain amplitude using two different prior distributions: a standard one, with no a priori assumptions about the orientation of Scorpius X-1; and an angle-restricted one, using a prior derived from electromagnetic observations. Median strain upper limits of 1.3 x 10(-24) and 8 x 10(-25) are reported at 150 Hz for the standard and angle-restricted searches respectively. This proof-of-principle analysis was limited to a short observation time by unknown effects of accretion on the intrinsic spin frequency of the neutron star, but improves upon previous upper limits by factors of similar to 1.4 for the standard, and 2.3 for the angle-restricted search at the sensitive region of the detector.

Advanced LIGO

The Advanced LIGO gravitational wave detectors are second-generation instruments designed and built for the two LIGO observatories in Hanford, WA and Livingston, LA, USA. The two instruments are identical in design, and are specialized versions of a Michelson interferometer with 4 km long arms. As in Initial LIGO, Fabry-Perot cavities are used in the arms to increase the interaction time with a gravitational wave, and power recycling is used to increase the effective laser power. Signal recycling has been added in Advanced LIGO to improve the frequency response. In the most sensitive frequency region around 100 Hz, the design strain sensitivity is a factor of 10 better than Initial LIGO. In addition, the low frequency end of the sensitivity band is moved from 40 Hz down to 10 Hz. All interferometer components have been replaced with improved technologies to achieve this sensitivity gain. Much better seismic isolation and test mass suspensions are responsible for the gains at lower frequencies. Higher laser power, larger test masses and improved mirror coatings lead to the improved sensitivity at mid and high frequencies. Data collecting runs with these new instruments are planned to begin in mid-2015.

L'11 Settembre Telematico Rischi di Sicurezza causati dai Social Network

Lo scopo di questa tesi è quello di progettare e sviluppare un sistema informatico in grado di verificare la possibilità di bypassare le comuni misure di sicurezza al fine di indicare soluzioni e strategie difensive efficaci. Più in dettaglio ci occuperemo di simulare gli atteggiamenti di un hacker, alta- mente invasivi e pericolosi, atti a compromettere l’intero sistema telematico su scala mondiale. Studiando i social network e le informazioni personali, ci si è resi conto, infatti, di come sia facile ed altamente probabile causare gravi danni sia all’intera popolazione del web che all’integrità delle infrastrutture telematiche.

Cultura "Open" e nuovi modelli normativi per la gestione della conoscenza

L'obiettivo della ricerca è di compiere un'analisi dell'impatto della cosiddetta cultura "open" alla luce dell'attuale condizione del World Wide Web. Si prenderà in considerazione, in particolare, la genesi del movimento a partire dalle basi di cultura hacker e la relativa evoluzione nella filosofia del software libero, con il fine ultimo di identificare il ruolo attuale del modello open source nello scenario esistente. L'introduzione al concetto di Open Access completerà la ricerca anche considerando la recente riaffermazione della conoscenza come bene comune all'interno della Società dell'Informazione

Chirale Störungsrechnung im Sektor ungerader innerer Parität bis zur chiralen Ordnung O(q 6)

Die vorliegende Dissertation behandelt den anomalen Sektor bzw. den Sektor ungerader innerer Parität in mesonischer chiraler Störungsrechnung (mesonische ChPT) bis zur chiralen Ordnung O(q^6). Auf eine Einführung in die Quantenchromodynamik (QCD) und ihrer Verknüpfung mit der chiralen Symmetrie folgt die Betrachtung der mesonischen ChPT im Sektor gerader sowie ungerader innerer Parität bis zur Ordnung O(q^4). Der sogenannte Wess-Zumino-Witten Term, welcher den Einfluss der axialen Anomalie bezogen auf die ChPT widerspiegelt, wird studiert. Anschließend wird die allgemeinste Lagrangedichte der Ordnung O(q^6) im Sektor ungerader innerer Parität detailiert analysiert. Sie enthält in ihrer SU(3)-Formulierung 23 Niederenergiekonstanten(low-energy constant=LEC). Aus Sicht der ChPT sind diese LECs freie Parameter, die auf irgendeine Art und Weise fixiert werden müssen. Es wird herausgearbeitet, bei welchen Prozessen und in welchen Kombinationen die jeweiligen LECs auftreten. Daraufhin wird versucht so viele dieser LECs wie möglich mittels Vektormesondominanz (VMD) sowie experimenteller Daten abzuschätzen und anzupassen. Hierfür wird zuerst die Vorgehensweise einer konsistenten Rechnung im Sektor ungerader innerer Parität bis zur Ordnung O(q^6) studiert, gefolgt von der Berechnung von insgesamt vierzehn geeigneten Prozessen im Rahmen der ChPT bis zur Ordnung O(q^6). Unter Verwendung experimenteller Daten werden dreizehn der LECs angepasst, wobei gegenwärtig nicht bei allen betrachteten Prozessen experimentelle Daten zur Verfügung stehen. Die Ergebnisse werden diskutiert und Unterschiede bzw. Übereinstimmungen mit anderen Rechnungen herausgearbeitet. Zusammenfassend erhält man einen umfassenden Einblick in den Sektor ungerader innerer Parität in mesonischer ChPT bis zur Ordnung O(q^6).

Mapping of a new locus for congenital anomalies of the kidney and urinary tract on chromosome 8q24

Congenital anomalies of the kidney and urinary tract (CAKUT) account for the majority of end-stage renal disease in children (50%). Previous studies have mapped autosomal dominant loci for CAKUT. We here report a genome-wide search for linkage in a large pedigree of Somalian descent containing eight affected individuals with a non-syndromic form of CAKUT.

Detection system for Escherichia coli-specific virulence genes: absence of virulence determinants in B and C strains

We describe a rational approach to simultaneously test Escherichia coli strains for the presence of known virulence genes in a reverse dot blot procedure. Specific segments of virulence genes of E. coli designed to have similar hybridization parameters were subcloned on plasmids and subsequently amplified by PCR as unlabeled probes in amounts sufficient to be bound to nylon membranes. Various pathogenic isolates and laboratory strains of E. coli were probed for the presence of virulence genes by labeling the genomic DNA of these strains with digoxigenin and then hybridizing them to the prepared nylon membranes. These hybridization results demonstrated that besides the E. coli K-12 safety strain derivatives, E. coli B and C strains are also devoid of genes encoding any of the investigated virulence factors. In contrast, pathogenic E. coli control strains, used to evaluate the method, showed typical hybridization patterns. The described probes and their easy application on a single filter were shown to provide a useful tool for the safety assessment of E. coli strains to be used as hosts in biotechnological processes. This approach might also be used for the identification and characterization of clinically significant E. coli isolates from human and animal species.

Comparative methodology to investigate the presence of Escherichia coli K-12 strains in environmental and human stool samples

This study was undertaken to evaluate the specificity and efficiency of different methods to detect Escherichia coli K-12 strains. Another aim was to determine the frequency of E. coli K-12 strains among wild-type E. coli isolates from different sources. The detection of K-12 strains was performed both genotypically by K-12 specific polymerase chain reaction (PCR) and on the basis of phenotypical tests. In addition, the genome structures of E. coli strains were characterized by pulsed-field gel electrophoresis (PFGE). The most specific results could be obtained by the genotypical tests PCR and PFGE as well as by the K-12 specific phage assay. In total, 131 stool and 95 water isolates as well as 14 K-12 derivatives were examined by the different methods. No E. coli K-12 strains were detected among the wild-type isolates.

Na 1 Nachlass Max Horkheimer, 74 - Korrespondenzen u.a. mit Käte von Hirsch (p. II 8, 232-369)

1 Brief von F. Pollock an Frederick J. Hacker, 1945; 1 Brief von Frederick J. Hacker an Max Horkheimer, sowie 2 Memoranden von Max Horkheimer; 5 Briefe zwischen Willy Hartner und Max Horkheimer, 1948; 3 Briefe und eine Drucksache von Fred Herzberg an Max Horkheimer, 1947; 1 Brief und 3 Memoranden von Max Horkheimer an Fred Herzberg, 1947; 2 Briefe von Heinz Herald an Max Horkheimer, 1946 sowie 1 Gutachten und Beilage von Max Horkheimer an Heinz Herald, 1946; 2 Briefe zwischen Josef Haurand und Max Horkheimer, 1949, 1950; 3 Briefe und Beilage zwischen Herta Herzog und Max Horkheimer, 1949; 23 Briefe zwischen dem Hessischen Staatsministerium für Kultus und Unterricht und Max Horkheimer, 1948-1949 siehe auch Hessischer Minister für Erziehung und Volkdsbildung; 2 Briefe von Eduard Heumann an Max Horkheimer, 1948-1949; 1 Brief und Beilage von George J. Hexter an A. Lourie; 35 Briefe zwischen Käte von Hirsch und Max Horkheimer, 1941-1948;

Na 1 Nachlass Max Horkheimer, 588 - Korrespondenzen mit Friedrich (Frederick) Pollock (p. VI 37, 1-180)

1 Telegramm von Leo Löwenthal an Frederick Pollock, 12.10.1953; 2 Briefe von Frederick Pollock an Frederick J. Hacker (Arzt), Oktober 1953; 1 Brief von Frederick J. Hacker (Arzt), an Theodor W. Adorno, 06.12.1950; 1 Brief von Frederick Pollock an Frederick Wild, 28.09.1953; 1 Brief von Frederick Wild an Max Horkheimer, 15.08.1953; 1 Brief von der Frankfurter Bücherstube an Frederick Pollock, 08.04.1953; 1 Brief von der Frankfurter Bücherstube an den Kurator W. Rau, 08.04.1953; 1 Brief von Frederick Pollock an die Guaranty Trust Company, 20.03.1953; 1 Brief von Germaine Krull-Ivens an Frederick Pollock, 14.01.1953;