Postoperative survival in patients with multiple brain metastases

BACKGROUND AND OBJECTIVE: Although surgery is traditionally performed for patients with a single brain metastasis, an increasing number of patients with multiple brain metastases may also be treated surgically. The objective of the study was to analyze postoperative survival results and the clinical factors affecting these results. MATERIAL AND METHODS: The records of the patients who underwent surgical resection of 2 or more lesions between January 2005 and January 2010 were retrospectively reviewed. Survival was calculated from the date of surgery to the last follow-up evaluation or death, and different clinical factors were analyzed in regard to patient survival. RESULTS: In total, 36 patients underwent one or more craniotomies. The survival of the total group ranged from 16 days to 37.5 months (mean, 29 months). There were 4 deaths within 30 days. When divided into Radiation Therapy Oncology Group RPA classes, the survival time was 11.75, 8.58, and 5.31 months for classes 1, 2, and 3, respectively. Regarding an impact on the survival, a significant association with a favorable outcome was found for the following factors: the number of brain metastases (2-3 vs. 4-6, P=0.046), RPA classes (1 vs. 2 or 3, P=0.0192), and extent of metastasis resection (all vs. partial, P=0.018). CONCLUSIONS: Well-selected patients with multiple brain metastases appear to benefit from surgery compared with historical controls of patients treated with whole-brain radiotherapy alone.publishersversionPeer reviewe

Development and experimental validation of high performance embedded intelligence and fail-operational urban surround perception solutions of the PRYSTINE project

Automated Driving Systems (ADSs) commend a substantial reduction of human-caused road accidents while simultaneously lowering emissions, mitigating congestion, decreasing energy consumption and increasing overall productivity. However, achieving higher SAE levels of driving automation and complying with ISO26262 C and D Automotive Safety Integrity Levels (ASILs) is a multi-disciplinary challenge that requires insights into safety-critical architectures, multi-modal perception and real-time control. This paper presents an assorted effort carried out in the European H2020 ECSEL project—PRYSTINE. In this paper, we (1) investigate Simplex, 1oo2d and hybrid fail-operational computing architectures, (2) devise a multi-modal perception system with fail-safety mechanisms, (3) present a passenger vehicle-based demonstrator for low-speed autonomy and (4) suggest a trust-based fusion approach validated on a heavy-duty truck.</p

Mechanical Pressure Induced Capacitance Changes of Polyisoprene/Nanostructured Carbon Black Composite Samples

Polyisoprene/nanostructured carbon black (PNCB) composite samples with different amount of carbon black (CB) filler were prepared. Investigations of mechanical pressure induced relative capacitance changes (RCC) depending on frequency (20 Hz – 2 MHz) were conducted. It was found that PNCB samples show pronounced and rather complex RCC effect, which depends on frequency, amount of filler (1 – 10 phr of CB) and pressure (from 0 to 234 kPa). At a certain frequency and a certain filler amount RCC effect changes its sign. Pressure induced capacitance changes at least for low CB filler concentrations are caused by piezopermittivity property of the PNCB composite

Influence of Laser Radiation on Electrical Resistivity of Polyisoprene/Nanostructured Carbon Composites

It is known that polymer/carbon nanotube composites are being tested for their potential use in optoelectronic devices. It is also known that polyisoprene/nanostructured carbon (PNC) composites have a pronounced resistance change under the influence of mechanical strain and vapour of volatile organic compounds. The goal of this study was to test PNC composites for their potential use as optoelectronic materials. Measurements of relative resistance change of poly- isoprene/nanostructured carbon black composites irradiated by semiconductor laser beam were conducted. One illustration of composites photoresistivity measurements at different intensities of laser radiation is given in Fig.1. Two competing mechanisms of composites resistivity change, induced by laser radiation, have been proposed: 1) photoconductivity of carbon nanostructures and 2) exponential reduction of tunnelling currents between carbon nanostructures in composite caused by to thermo-optically induced matrix expansion. Further photoresistivity and optical studies of PNC composites are in progress

Electrical Resistance Change Effect in Polyisoprene/Nanostructured Carbon Composite Induced by Laser Radiation

Polyisoprene/nanostructured carbon (PNC) composites are known for their ability to change electrical resistance rapidly under the influence of mechanical strain and vapour of volatile organic compounds. Previously testing of PNC composites containing carbon black (CB) filler were made to check for the possibility to sense optical radiation. In this study attempt to determine the difference in resistance change response depending on laser wavelength was done. PNC composite samples cyclically were irradiated with laser beams of different wavelengths. Irradiation time during one cycle was 30 s. Measure-ments with sample containing 8 phr of CB showed that relative resistance change effect is larger when irradiating the sample with 532 nm laser beam compared to 980 nm laser beam. To clarify the mechanism for such difference in relative resistance change further PNC composite tests are being made

Piezocapacitance Effect in Polyisoprene/High Structure Carbon Black Composites

Piezoresistance effect of elastomer nanocomposites containing conductive nanoparticles is well known [1,2]. Capacitance (permittivity) changes of polymer nanocomposites, depending on filler concentration, frequency and temperature have also been studied [3,4]. We have not found papers about piezocapacitance effect in elastomer/conductive nanoparticle structures. In this work we searched for piezocapacitance effect in polyisoprene/high structure carbon (PHCB) composites and pronounced effect was found

Effect of Roll Mill Mixing on AC Conductance of Polyisoprene/Nanostructured Carbon Composites

Polyisoprene/Nanostructured carbon (PNC) composites have drawn their attention due to their pronounced piezoresistive properties which can be used for stress/strain sensor applications [1, 2]. To achieve optimal piezoresistive properties of PNC composite samples it is crucial to identify all the sensor-effect influencing factors during sample manufacturing process. It has already been shown that conductive nanoparticle network in the PNC composite largely forms during vulcanization process [3]. Our current work was done to find out an influence of two roll mill (TRM) mixing of a raw PNC composite on AC conductance of finalized (vulcanized) PNC composite samples