869 research outputs found
BB-RTE: a Budget-Based RunTime Engine for Mixed and Safety Critical Systems
International audienceThe safety critical industry is considering a shift from single-core COTS to multi-core COTS processor for safety and time critical computers in order to maximize performance while reducing costs.In a domain where time predictability is a major concern due to the regulation standards, multi-core processors are introducing new sources of time variations due to the electronic competition when the software is accessing shared hardware resources, and characterized by timing interference.The solutions proposed in the literature to deal with timing interference are all proposing a trade-off between performance efficiency, time predictability and intrusiveness in the software. Especially, none of them is able to fully exploit the multi-core efficiency while allowing untouched, already-certified legacy software to run.In this paper, we introduce and evaluate BB-RTE, a Budget-Based RunTime Engine for Mixed and Safety Critical Systems, that especially focuses on mixed critical systems. BB-RTE guarantees the deadline of high-critical tasks 1) by computing for each shared hardware resource a budget in terms of extra accesses that the critical tasks can support before their runtime is significantly impacted; 2) by temporarily suspending low-critical tasks at runtime once this budget as been consumed
Correlation between electric-field-induced phase transition and piezoelectricity in lead zirconate titanate films
We observed that electric field induces phase transition from tetragonal to
rhombohedral in polycrystalline morphotropic lead zirconate titanate (PZT)
films, as reported in 2011 for bulk PZT. Moreover, we evidenced that this
field-induced phase transition is strongly correlated with PZT film
piezoelectric properties, that is to say the larger the phase transition, the
larger the longitudinal piezoelectric coefficient d 33,eff . Although d 33,eff
is already comprised between as 150 to 170 pm/V, our observation suggests that
one could obtain larger d 33,eff values, namely 250 pm/V, by optimizing the
field-induced phase transition thanks to composition fine tuning
METrICS: a Measurement Environment For Multi-Core Time Critical Systems
International audienceWith the upcoming shift from single-core to multi-core COTS processor for safety critical products such as avionics, railway or space computer subsystems, the safety critical industry is facing a trade-off in term of performance versus predictability.In multi-core processors, concurrent accesses to shared hardware resources are generating inter-task or inter-application timing interference, breaking the timing isolation principles required by the standards for such critical software. Several solutions have been proposed in the literature to control or regulate these timing interferences, but most of these solutions require to perform some level of profiling, monitoring or dimensioning.As time-critical software is running on top of Real Time Operating Systems (ROTS), classical profiling techniques relying on interrupts, multi-threading, or OS modules are either not available or prohibited for predictability, safety or security reasons.In this paper we present METrICS, a measurement environment for multi-core time-critical systems running on top of the industry-standard PikeOS RTOS. Our framework proposes an accurate real-time runtime and resource usage measurement while having a negligible impact on timing behaviour, allowing us to fully observe and characterize timing interference.Beyond being able to characterize timing interference, we evaluated METrICS in term of accuracy of the timing and resource usage measurements, intrusiveness both in term of timing and impact on the legacy code, as well as adherence to the hardware. We also present a portfolio of the kind of measurements METrICS provides
Piezoelectric nanoelectromechanical resonators based on aluminum nitride thin films
We demonstrate piezoelectrically actuated, electrically tunable nanomechanical resonators based on multilayers containing a 100-nm-thin aluminum nitride (AlN) layer. Efficient piezoelectric actuation of very high frequency fundamental flexural modes up to ~80 MHz is demonstrated at room temperature. Thermomechanical fluctuations of AlN cantilevers measured by optical interferometry enable calibration of the transduction responsivity and displacement sensitivities of the resonators. Measurements and analyses show that the 100 nm AlN layer employed has an excellent piezoelectric coefficient, d_(31)=2.4 pm/V. Doubly clamped AlN beams exhibit significant frequency tuning behavior with applied dc voltage
Oligosarcomas, IDH-mutant are distinct and aggressive
Oligodendrogliomas are defined at the molecular level by the presence of an IDH mutation and codeletion of chromosomal arms 1p and 19q. In the past, case reports and small studies described gliomas with sarcomatous features arising from oligodendrogliomas, so called oligosarcomas. Here, we report a series of 24 IDH-mutant oligosarcomas from 23 patients forming a distinct methylation class. The tumors were recurrences from prior oligodendrogliomas or developed de novo. Precursor tumors of 12 oligosarcomas were histologically and molecularly indistinguishable from conventional oligodendrogliomas. Oligosarcoma tumor cells were embedded in a dense network of reticulin fibers, frequently showing p53 accumulation, positivity for SMA and CALD1, loss of OLIG2 and gain of H3K27 trimethylation (H3K27me3) as compared to primary lesions. In 5 oligosarcomas no 1p/19q codeletion was detectable, although it was present in the primary lesions. Copy number neutral LOH was determined as underlying mechanism. Oligosarcomas harbored an increased chromosomal copy number variation load with frequent CDKN2A/B deletions. Proteomic profiling demonstrated oligosarcomas to be highly distinct from conventional CNS WHO grade 3 oligodendrogliomas with consistent evidence for a smooth muscle differentiation. Expression of several tumor suppressors was reduced with NF1 being lost frequently. In contrast, oncogenic YAP1 was aberrantly overexpressed in oligosarcomas. Panel sequencing revealed mutations in NF1 and TP53 along with IDH1/2 and TERT promoter mutations. Survival of patients was significantly poorer for oligosarcomas as first recurrence than for grade 3 oligodendrogliomas as first recurrence. These results establish oligosarcomas as a distinct group of IDH-mutant gliomas differing from conventional oligodendrogliomas on the histologic, epigenetic, proteomic, molecular and clinical level. The diagnosis can be based on the combined presence of (a) sarcomatous histology, (b) IDH-mutation and (c) TERT promoter mutation and/or 1p/19q codeletion, or, in unresolved cases, on its characteristic DNA methylation profile.
Keywords: 1p/19q; Codeletion; DNA methylation; Gliosarcoma; NF1; Oligodendroglioma; Oligosarcoma; Prognosis; SMA; Subtype; TERT; TP53; Type; Variant; YAP1
Venous thromboembolic events in glioblastoma patients: An epidemiological study
BACKGROUND AND PURPOSE
Venous thromboembolic events (VTEs) are a major complication in cancer patients, and therefore, also in brain cancer patients, anticoagulants are considered appropriate in the treatment of VTEs.
METHODS
Frequency, risk factors, and treatment of VTEs, as well as associated complications, were assessed in a population-based cohort of glioblastoma patients in the Canton of Zurich, Switzerland. Correlations between clinical data and survival were retrospectively analyzed using the log-rank test and Cox regression models.
RESULTS
Four hundred fourteen glioblastoma patients with isocitrate dehydrogenase wild-type status were identified. VTEs were documented in 65 patients (15.7%). Median time from tumor diagnosis to the occurrence of a VTE was 1.8 months, and 27 patients were diagnosed with VTEs postoperatively (within 35âdays; 42.2%). History of a prior VTE was more common in patients who developed VTEs than in those who did not (p =â0.004). Bevacizumab treatment at any time during the disease course was not associated with occurrence of VTEs (p =â0.593). Most patients with VTEs (n =â61, 93.8%) were treated with therapeutic anticoagulation. Complications occurred in 14 patients (23.0%), mainly intracranial hemorrhages (n =â7, 11.5%). Overall survival did not differ between patients diagnosed with VTEs and those who had no VTE (p =â0.139). Tumor progression was the major cause of death (n =â283, 90.7%), and only three patients (1.0%) died in association with acute VTEs.
CONCLUSIONS
Venous thromboembolic events occurred early in the disease course, suggesting that the implementation of primary venous thromboembolism prophylaxis during first-line chemoradiotherapy could be explored in a randomized setting
How we treat patients with leptomeningeal metastases
The goal of treatment of leptomeningeal metastasis is
to improve survival and to maintain quality of life by
delaying neurological deterioration. Tumour-specific
therapeutic options in
Transmission of Bartonella henselae by Ixodes ricinus
The causative agent of cat-scratch disease in humans can be transmitted by this tick through saliva
Leptomeningeal metastasis from solid tumours: EANOâESMO Clinical Practice Guideline for diagnosis, treatment and follow-up
Central nervous system; Clinical practice guideline; NeurologicalSistema nerviĂłs central; Guia de prĂ ctica clĂnica; NeurolĂČgicSistema nervioso central; GuĂa de prĂĄctica clĂnica; NeurolĂłgicoThis Clinical Practice Guideline provides recommendations for managing leptomeningeal metastases from solid tumours
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