Search results for "Instrumentation"
showing 10 items of 4914 documents
Decompression/Stabilization of the Metastatic Spine: Cotrel-Dubousset-Lnstrumentation in 50 Patients Jan
1993
50 patients with metastatic disease of the spine underwent dorsal decompression and stabilization with the Cotrel-Dubousset-Instrumentation from 1987 to 1991. Indications for surgical treatment were neurologic deficit, spinal instability, and/or pain resistant to medical or radiation treatment. No external orthotics were used postoperatively. Pain was relieved dramatically in 45 patients. Among 25 patients suffering from neurologic deficit preoperatively, 13 improved, 15 remained unchanged, whereas 2 developed an incomplete, transient paraplegia. 15 (7) patients were alive after 1 (2) years. Postoperative complications were frequent, but there were only 2 failures of the stabilization devic…
Outcome after palliative posterior surgery for metastatic disease of the spine - evaluation of 106 consecutive patients after decompression and stabi…
1999
From 1987 to 1996, 106 consecutive patients with metastatic disease of the spine who underwent palliative decompression from a dorsal approach and subsequent stabilisation with Cotrel-Dubousset instrumentation (CDI) were followed prospectively, and independent of the surgeons. Parameters evaluated were neurological function, perioperative complications, survival and rehabilitation. Following the Frankel system for the assessment of neurological disorder, 33 patients had a major deficit (grade A, B or C), 23 a minor deficit (grade D) and 50 no deficit. If there was no neurological dysfunction, the only patients who underwent operation were those graded as class IV according to Harrington. Ou…
Evaluation of robot-guided minimally invasive implantation of 2067 pedicle screws
2017
ObjectiveRecent studies have investigated the role of spinal image guidance for pedicle screw placement. Many authors have observed an elevated placement accuracy and overall improvement of outcome measures. This study assessed a bi-institutional experience following introduction of the Renaissance miniature robot for spinal image guidance in Europe.MethodsThe medical records and radiographs of all patients who underwent robot-guided implantation of spinal instrumentation using the novel system (between October 2011 and March 2015 in Mainz and February 2014 and February 2016 in Regensburg) were reviewed to determine the efficacy and safety of the newly introduced robotic system. Screw posit…
Flapless application of enamel matrix derivative in periodontal retreatment: A multicentre randomized feasibility trial
2021
AIM To investigate the potential benefit of enamel matrix derivative (EMD) as adjunct to re-instrumentation of residual pockets persisting after steps 1 and 2 of periodontal therapy. MATERIAL AND METHODS 44 adult patients participated in a multicentre feasibility randomized clinical trial with split-mouth design. They had presented at re-evaluation after initial non-surgical periodontal therapy (steps 1 and 2 of periodontal therapy) for generalized periodontitis with at least 2 teeth with residual probing pocket depths (PPD) ≥5 and ≤8 mm, with bleeding on probing (BOP). Two teeth with similar PPD were randomized to receive re-instrumentation either with (test) or without (control) adjunctiv…
A Novel Deep Learning Stack for APT Detection
2019
We present a novel Deep Learning (DL) stack for detecting Advanced Persistent threat (APT) attacks. This model is based on a theoretical approach where an APT is observed as a multi-vector multi-stage attack with a continuous strategic campaign. To capture these attacks, the entire network flow and particularly raw data must be used as an input for the detection process. By combining different types of tailored DL-methods, it is possible to capture certain types of anomalies and behaviour. Our method essentially breaks down a bigger problem into smaller tasks, tries to solve these sequentially and finally returns a conclusive result. This concept paper outlines, for example, the problems an…
Application of time-of-flight aerosol mass spectrometry for the online measurement of gaseous molecular iodine.
2012
Here we present a new application of a time-of-flight aerosol mass spectrometer (TOF-AMS) for the measurement of atmospheric trace gases in real-time. Usually, TOF-AMS instruments are not sensitive to gas-phase species due to the aerodynamic particle focusing inlet system which reduces the gas phase species by a factor of about 10(7) relative to the particle phase. This efficient removal of the gas phase and the resulting high relative enrichment of particles is one reason for the very high sensitivity of TOF-AMS instruments for particle phase compounds (detection limits in the sub-μg/m(3)-range for online measurements with 1 min integration time), which allows application of the instrument…
Automatic calculation of massive two-loop self-energies with XLOOPS
1997
Abstract Within the program package XLOOPS it is possible to calculate self-energies up to the two-loop level for arbitrary massive particles. The program package — written in MAPLE (Char et al., Maple V Language Reference Manual (Springer, 1991); Char et al., Maple V Library Reference Manual (Springer, 1991)) — is designed to deal with the full tensor structure of the occurring integrals. This means that applications are not restricted to those cases where the reduction to scalars via equivalence theorem is allowed. The algorithms handle two-loop integrals analytically if this is possible. For those topologies where no analytic result for the general mass case is available, the diagrams ar…
A Refractive Index Sensor Based on the Resonant Coupling to Cladding Modes in a Fiber Loop
2013
We report an easy-to-build, compact, and low-cost optical fiber refractive index sensor. It consists of a single fiber loop whose transmission spectra exhibit a series of notches produced by the resonant coupling between the fundamental mode and the cladding modes in a uniformly bent fiber. The wavelength of the notches, distributed in a wavelength span from 1,400 to 1,700 nm, can be tuned by adjusting the diameter of the fiber loop and are sensitive to refractive index changes of the external medium. Sensitivities of 170 and 800 nm per refractive index unit for water solutions and for the refractive index interval 1.40-1.442, respectively, are demonstrated. We estimate a long range resolut…
Development of a test station for accurate in situ I-V curve measurements of photovoltaic modules in Southern Norway
2011
The development of an outdoor test station for accurate in situ I-V curve measurements of photovoltaic (PV) modules is described. The modules are installed in an open-rack configuration at the University of Agder in Southern Norway. Seven new and three aged PV modules of different type and make are being tested, including mono-and multicrystalline silicon from differing manufacturing routes, triple-junction amorphous silicon, and CIS. Data acquisition is controlled with a multichannel electronic load system and LabVIEW software, recording high-resolution I-V curves at one-minute intervals. Between I-V curve sweeps, each module is operated at the maximum power point. Characteristic electrica…
Detection of Amyloid-β Fibrils Using Track-Etched Nanopores: Effect of Geometry and Crowding
2021
Several neurodegenerative diseases have been linked to proteins or peptides that are prone to aggregate in different brain regions. Aggregation of amyloid-β (Aβ) peptides is recognized as the main cause of Alzheimer's disease (AD) progression, leading to the formation of toxic Aβ oligomers and amyloid fibrils. The molecular mechanism of Aβ aggregation is complex and still not fully understood. Nanopore technology provides a new way to obtain kinetic and morphological aspects of Aβ aggregation at a single-molecule scale without labeling by detecting the electrochemical signal of the peptides when they pass through the hole. Here, we investigate the influence of nanoscale geometry (conical an…