Changing clinical and therapeutic trends in tentorial dural arteriovenous fistulas: a systematic review

BACKGROUND AND PURPOSE: Tentorial dural arteriovenous fistulas are characterized by a high hemorrhagic risk. We evaluated trends in outcomes and management of tentorial dural arteriovenous fistulas and performed a meta-analysis evaluating clinical and angiographic outcomes by treatment technique. MATERIALS AND METHODS: We performed a comprehensive literature search for studies on surgical and endovascular treatment of tentorial dural arteriovenous fistulas. We compared the proportion of patients undergoing endovascular, surgical, and combined endovascular/surgical management; the proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas; and proportion of patients with good neurologic outcome across 3 time periods: 1980-1995, 1996-2005, and 2006-2014. We performed a random-effects meta-analysis, evaluating the rates of occlusion, long-term good neurologic outcome, perioperative morbidity, and resolution of symptoms for the 3 treatment modalities. RESULTS: Twenty-nine studies with 274 patients were included. The proportion of patients treated with surgical treatment alone decreased from 38.7% to 20.4% between 1980-1995 and 2006-2014. The proportion of patients treated with endovascular therapy alone increased from 16.1% to 48.0%. The proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas decreased from 64.4% to 43.6%. The rate of good neurologic outcome increased from 80.7% to 92.9%. Complete occlusion rates were highest for patients receiving multimodality treatment (84.0%; 95% CI, 72.0%-91.0%) and lowest for endovascular treatment (71.0%; 95% CI, 56.0%-83.0%; P < .01). Long-term good neurologic outcome was highest in the endovascular group (89.0%; 95% CI, 80.0%-95.0%) and lowest for the surgical group (73.0%; 95% CI, 51.0%-87.0%; P < .03). CONCLUSIONS: Patients with tentorial dural arteriovenous fistulas are increasingly presenting with unruptured lesions, being treated endovascularly, and experiencing higher rates of good neurologic outcomes. Endovascular treatment was associated with superior neurologic outcomes but lower occlusion rate

Gaseous optical contamination of the spacecraft environment: A review

Interactions between the ambient atmosphere and orbiting spacecraft, sounding rockets, and suborbital vehicles, and with their effluents, give rise to optical (extreme UV to LWIR) foreground radiation which constitutes noise that raises the detection threshold for terrestrial and celestial radiations, as well as military targets. Researchers review the current information on the on-orbit optical contamination. Its source species are created in interaction processes that can be grouped into three categories: (1) Reactions in the gas phase between the ambient atmosphere and desorbates and exhaust; (2) Reactions catalyzed by exposed ram surfaces, which occur spontaneously even in the absence of active material releases from the vehicles; and (3) Erosive excitative reactions with exposed bulk (organic) materials, which have recently been identified in the laboratory though not as yet observed on spacecraft. Researchers also assess the effect of optical pumping by earthshine and sunlight of both reaction products and effluents

Optical, structural and thermal properties of hybrid PVA/CaAl2ZrO6 nanocomposite films

This report focuses on fabrication, characterization, and fundamental optical, structural and thermal properties of PVA/calcium aluminum doped zirconate (CaAl2ZrO6) nanocomposites (NCs) films. The PVA-NCs with different amounts viz., 2, 4, 6 and 8 wt% of calcium aluminum zirconate (CaAl2ZrO6) have been fabricated using solvent casting technique. The NC films structural and morphology have been investigated by X-ray diffraction, FTIR and scanning electron microscopy. TEM result indicates that the size of nanoparticles (NPs) lies in the range 10-23nm.. Thermal studies have been evaluated by differential scanning calorimetry (DSC). The optical properties of NCs has been investigated by UV-vis spectroscopy, where the optical study reveals an increased refractive index from 1.22 to 2.23 at a wave length of 300 nm, where as the band gap energy (E-g) is reduced from 5.01 to 3.32 eV for PVA to PVA/8wt% CaAl2ZrO6, respectively. The dielectric studies, optical conductivity measurements and Urbach energy analysis also supports the dopant dependent optical property, tuning of PVA/CaAl2ZrO6 NC films to enable effective material property engineering to suit specified application requirements

Data for proteome analysis of Bacillus lehensis G1 in starch-containing medium

Bacillus lehensis G1 is a cyclodextrin glucanotransferase (CGTase) producer, which can degrade starch into cyclodextrin. Here, we present the proteomics data of B. lehensis cultured in starch-containing medium, which is related to the article “Proteome-based identification of signal peptides for improved secretion of recombinant cyclomaltodextrin glucanotransferase in Escherichia coli” (Ling et. al, in press). This dataset was generated to better understand the secretion of proteins involved in starch utilization for bacterial sustained growth. A 2-DE proteomic technique was used and the proteins were tryptically digested followed by detection using MALDI-TOF/TOF. Proteins were classified into functional groups using the information available in SubtiList webserver (http://genolist.pasteur.fr/SubtiList/)

Switchable Wideband Metamaterial Absorber and AMC reflector for X-band Applications and Operations

A single layered metamaterial structure with capabilities of switching from a wideband metamaterial absorber to an AMC reflector and vice versa is presented in this paper. A flame retardant 4 substrate with physical thickness of 1.60mm was used. The absorption rate, reflection rate, reflection phase and surface current distribution were studied and discussed. The operational incidental wave angles were varied from 0o to 65o. A peak reflection of about 90% was achieved at 11.20 GHz with a usable bandwidth (-90 to +90) of 3.01 GHz by the AMC reflector. The metamaterial absorber demonstrated a wideband performance (from 8.10 GHz to 14.30 GHz). It achieved 100% absorption at 11.20 GHz and not less than 6

Frequency Reconfigurable Epsilon Negative Metamaterial Antenna

This paper proposes metamaterial (MTM) inspired frequency reconfigurable antenna based on thecircular electric field coupled (ELC) resonator. It is composed of circular shape ELC resonator with the radius size of 7 mm. By inserting two switches between the gaps at both side of the circular ELC resonator, it is possible to switch ON or OFF the unit cell. The antenna has been simulated using CST Microwave Studio software tool. The simulation result shows that the proposed antenna is capable of reconfiguring between two different frequencies which are2.18 GHz and 2.64 GHz. The simulated bandwidth at -10 dB is 4.12 % at resonance frequency of 2.18 GHz and 8.7% at 2.64 GH

X-band operations metamaterial absorber with extended circular ring topology for size reduction

A metamaterial electromagnetic wave absorber consisting of a big circular ring patch with four smaller suppression circular rings is presented in this report. The metamaterial electromagnetic wave absorber introduces the concept of size reduction by suppressing the resonance frequency. An FR4 substrate was used and the incidental wave angles were varied from 00 to 600. Simulations results shows peak absorption of 100% was achieved at 10.7 GHz by the absorber for both TE and TM polarization incident waves. Minimum absorption for both TE and TM mode of 90.6% was achieved under TE mode. The metamaterial absorber was being tested with and Ultra-wide band antenna and the results were reported. © 2017, Institute of Advanced Engineering and Science. All rights reserved