A high frequency builder software for arbitrary radio frequency signals

While the frequencies accessible by signal generators steadily rise, the synthesization of complex and arbitrary waveforms with high frequency components remains challenging, especially when restricted by an external reference clock. In this article, we present a comprehensive software package combined with state of the art hardware as a solution for the generation of highly sampled, arbitrary radio frequency waveforms. The software can be used to conduct both synchronous and heterodyne pump probe experiments due to a variety of different synchronization modules. While both kinds of modules allow for standard waveforms, such as sines, pulses, and bursts, as well as any arbitrary signal, the heterodyne modules additionally are not restricted by the reference clock frequency. Both the output and the synchronization module can be adapted to support additional measurement devices. Due to the modular software structure, individual classes can be exchanged while maintaining all functionalities. The software provides a user friendly graphical interface that allows us to compose, save, and load complex arbitrary waveforms within only a few steps. The frequency selectivity provided by the software hardware combination allows us to directly target specific excitation states of physical systems. Conducting a heterodyne scanning transmission x ray microscopy experiment, we are able to demonstrate the capabilities of the software when paired with a high sample rate arbitrary waveform generator. The heterodyne synchronization modules allow for unlimited flexibility leveraging arbitrary waveform generation to their full power. By solving the challenges of synthesizing highly complex electromagnetic waves, the software enables a large variety of experiments to be performed more convenientl

Smad4-expression is decreased in breast cancer tissues: a retrospective study

BACKGROUND: Although transforming growth factor β (TGF-β) typically inhibits proliferation of epithelial cells, consistent with a tumor suppressor activity, it paradoxically also exhibits pro-metastatic activity in the later stages of carcinogenesis. Since tumors often display altered TGF-β signaling, particularly involving the Smad-pathway, we investigated the role of Smad4-expression in breast cancer. METHODS: Smad4 expression was investigated by immunohistochemistry in formalin-fixed, paraffin-embedded tissue from 197 samples of primary breast cancer obtained between 1986 and 1998. The prognostic value of Smad4-expression was analyzed. RESULTS: Smad4 expression was found to be reduced in lobular and ductal breast carcinoma as compared to surrounding uninvolved lobular and ductal breast epithelia (p < 0.001, n = 50). Smad4-expression correlated positively with expression of TGF-β-receptor I (p < 0.001, n = 197) and TGF-β-receptor II (p < 0.001, n = 197), but showed no significant correlation with tumor size, metastases, nodal status, histological grade, histological type, or estrogen receptor expression. While not achieving statistical significance, there was a trend towards longer survival times in patients with Smad4 negative tumors. CONCLUSION: According to the suggested role of Smad4 as a tumor suppressor we observed that expression of Smad4 is lower in human breast cancer than in surrounding breast epithelium. However, we also observed a trend towards longer survival times in Smad4-negative patients, indicating the complex role of TGF-β signaling in tumor progression

Asymptotic Confidence Spheres in Certain Banach Spaces via Covariance Operators

Gaussian limits of processes with values in type 2 Banach spaces can be used to construct asymptotic confidence regions of spherical shape. This is done by estimating the covariance of the limit distribution. Nuclearity of the covariance operators makes it possible to work in subspaces of growing dimension, which is useful for applications. As an example, a Robbins-Monro algorithm is treated.

Komplikationen und Mortalität nach Pneumonektomie bei Rauchern mit NSCLC

Objective: Perioperative morbidity and mortality in patients receiving pneumonectomy because of non-small cell lung cancer (NSCLC) remains quite high. The aim of this study is to identify risk factors to minimize perioperative mortality and morbidity. Patients and method: The results of 156 Patients who received pneumonectomy between 1995 and 2004 were reviewed retrospectively. All patients had stage I or II NSCLC. In 81 cases a right sided and in 75 a left sided pneumonectomy was performed. Cardiopulmonary function tests were sufficient for pneumonectomy. Results: Overall perioperative 30-day mortality was 7.1% (n=11), in hospital mortality 8.3% (n=13). The cause was sepsis in 6 cases, cardiac failure in 4 cases, and respiratory insufficiency in 3 cases. In univariable and multivariable regression analysis considering mortality, none of the prognostic factors reached significance. The odds ratio for postoperative death was 1.6 fold for smokers in comparison to non smokers. Complications after pneumonectomy were seen in 34.6%, with arrhythmia in 16.0%, sepsis in 1.9% and bronchopleural fistula (BPF) occurring in 6.4%. Smoking and intraoperative blood loss >500 ml were highly significant perioperative risk factors. Conclusion: Smoking until operation and intraoperative blood loss were independent postoperative risk factors leading to complications after pneumonectomy for NSCLC. The risk for complications was 2.8-fold higher for smokers.Ziel: Nach wie vor ist die perioperative Morbidität und Mortalität bei Patienten, die sich auf Grund eines nicht-kleinzelligem Lungenkarzinoms einer Pneumonektomie unterziehen müssen, sehr hoch. Das Ziel dieser Studie ist, Risikofaktoren zu identifizieren und dadurch die Morbidität und Mortalität zu senken. Patienten und Methode: Die Daten von 156 Patienten, die zwischen 1995 und 2004 auf Grund eines nicht-kleinzelligen Lungenkarzinoms im Stadium I und II pneumonektomiert werden mussten, wurden retrospektiv ausgewertet. In 81 Fällen wurde die Pneumonektomie rechts und in 75 Fällen links vorgenommen. Sowohl kardiale als auch pulmonale Funktionsparameter qualifizierten die Patienten für eine Pneumonektomie. Resultate: Die 30-Tage-Mortalität betrug 7,1% (n=11), die Krankenhausletalität 8,3% (n=13). Die Ursachen waren eine Sepsis bei 6 Patienten, Herzversagen bei 4 Patienten und pulmonale Probleme bei 3 Patienten. Bezüglich der Letalität erreichte keiner der Prognosefaktoren sowohl in der univariablen als auch der multivariablen Regression statistische Signifikanz. Die Odds-Ratio, postoperativ zu versterben, betrug bei den Rauchern 1,6. Komplikationen traten in 34,6% auf, am häufigsten Arrhythmie bei 16,0%, Sepsis in 1,9% und Bronchusstumpfinsuffizienz in 6,4%. Rauchen und intraoperativer Blutverlust >500 ml waren hoch signifikante perioperative Risikofaktoren. Schlussfolgerung: Rauchen bis zur Operation und intraoperativer Blutverlust sind unabhängige perioperative Risikofaktoren nach Pneumonektomie bei nicht-kleinzelligem Lungenkarzinom. Das Risiko, postoperativ Komplikationen zu entwickeln, war 2,8-mal höher bei Rauchern