bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurements of volatile organic compounds at a suburban ground site (T1) in Mexico City during the MILAGRO 2006 campaign: measurement comparison, emission ratios, and source attribution
Authors: Bon D. M. , Ulbrich I. M. , de Gouw J. A. , Warneke C. , Kuster W. C. , Alexander M. L. , Baker A. , Beyersdorf A. J. , Blake D. , Fall R. , Jimenez J. L. , Herndon S. C. , Huey L. G. , Knighton W. B. , Ortega J. , Springston S. , Vargas O.
Published: March 2011

Abstract. Volatile organic compound (VOC) mixing ratios were measured with two different instruments at the T1 ground site in Mexico City during the Megacity Initiative: Local and Global Research Observations (MILAGRO) campaign in March of 2006. A gas chromatograph with flame ionization detector (GC-FID) quantified 18 light alkanes, alkenes and acetylene while a proton-transfer-reaction ion-trap mass spectrometer (PIT-MS) quantified 12 VOC species including oxygenated VOCs (OVOCs) and aromatics. A GC separation system was used in conjunction with the PIT-MS (GC-PIT-MS) to evaluate PIT-MS measurements and to aid in the identification of unknown VOCs. The VOC measurements are also compared to simultaneous canister samples and to two independent proton-transfer-reaction mass spectrometers (PTR-MS) deployed on a mobile and an airborne platform during MILAGRO. VOC diurnal cycles demonstrate the large influence of vehicle traffic and liquid propane gas (LPG) emissions during the night and photochemical processing during the afternoon. Emission ratios for VOCs and OVOCs relative to CO are derived from early-morning measurements. Average emission ratios for non-oxygenated species relative to CO are on average a factor of ~2 higher than measured for US cities. Emission ratios for OVOCs are estimated and compared to literature values the northeastern US and to tunnel studies in California. Positive matrix factorization analysis (PMF) is used to provide insight into VOC sources and processing. Three PMF factors were distinguished by the analysis including the emissions from vehicles, the use of liquid propane gas and the production of secondary VOCs + long-lived species. Emission ratios to CO calculated from the results of PMF analysis are compared to emission ratios calculated directly from measurements. The total PIT-MS signal is summed to estimate the fraction of identified versus unidentified VOC species.
Carbon dioxide atmospheric vertical profiles retrieved from space observation using ACE-FTS solar occultation instrument
Authors: Foucher P. Y. , Chédin A. , Armante R. , Boone C. , Crevoisier C. , Bernath P.
Published: March 2011

Abstract. Major limitations of our present knowledge of the global distribution of CO2 in the atmosphere are the uncertainty in atmospheric transport and the sparseness of in situ concentration measurements. Limb viewing spaceborne sounders such as the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) offer a vertical resolution of a few kilometres for profiles, which is much better than currently flying or planned nadir sounding instruments can achieve. After having demonstrated the feasibility of obtaining CO2 vertical profiles in the 5–25 km altitude range with an accuracy of about 2 ppm in a previous study, we present here the results of five years of ACE-FTS observations in terms of monthly mean profiles of CO2 averaged over 10° latitude bands for northern mid-latitudes. These results are compared with in-situ aircraft measurements and with simulations from two different air transport models. Key features of the measured altitude distribution of CO2 are shown to be accurately reproduced by the ACE-FTS retrievals: variation in altitude of the seasonal cycle amplitude and extrema, seasonal change of the vertical gradient, and mean growth rate. We show that small but significant differences from model simulations could result from an over estimation of the model circulation strength during the northern hemisphere spring. Coupled with column measurements from a nadir viewing instrument, it is expected that occultation measurements will bring useful constraints to the surface carbon flux determination.
Ozone production in remote oceanic and industrial areas derived from ship based measurements of peroxy radicals during TexAQS 2006
Authors: Sommariva R. , Brown S. S. , Roberts J. M. , Brookes D. M. , Parker A. E. , Monks P. S. , Bates T. S. , Bon D. , de Gouw J. A. , Frost G. J. , Gilman J. B. , Goldan P. D. , Herndon S. C. , Kuster W. C. , Lerner B. M. , Osthoff H. D. , Tucker S. C. , Warneke C. , Williams E. J. , Zahniser M. S.
Published: March 2011

Abstract. During the Texas Air Quality Study II (TexAQS 2006) campaign, a PEroxy Radical Chemical Amplifier (PERCA) was deployed on the NOAA research vessel R/V Brown to measure total peroxy radicals (HO2+Σ RO2). Day-time mixing ratios of HO2+Σ RO2 between 25 and 110 ppt were observed throughout the study area – the Houston/Galveston region and the Gulf coast of the US – and analyzed in relation to measurements of nitrogen oxides, volatile organic compounds (VOC) and photolysis rates to assess radical sources and sinks in the region. The measurements of HO2+Σ RO2 were used to calculate the in-situ net photochemical formation of ozone. Measured median values ranged from 0.6 ppb/h in clean oceanic air masses up to several tens of ppb/h in the most polluted industrial areas. The results are consistent with previous studies and generally agree with observations made during the previous TexAQS 2000 field campaign. The net photochemical ozone formation rates determined at Barbours Cut, a site immediately south of the Houston Ship Channel, were analyzed in relation to local wind direction and VOC reactivity to understand the relationship between ozone formation and local VOC emissions. The measurements of HO2+Σ RO2 made during the R/V Brown TexAQS 2006 cruise indicate that ozone formation is NOx-limited in the Houston/Galveston region and influenced by highly reactive hydrocarbons, especially alkenes from urban and industrial sources and their photo-oxidation products, such as formaldehyde.
Large methane releases lead to strong aerosol forcing and reduced cloudiness
Authors: Kurtén T. , Zhou L. , Makkonen R. , Merikanto J. , Räisänen P. , Boy M. , Richards N. , Rap A. , Smolander S. , Sogachev A. , Guenther A. , Mann G. W. , Carslaw K. , Kulmala M.
Published: March 2011

Abstract. The release of vast quantities of methane into the atmosphere as a result of clathrate destabilization is a potential mechanism for rapid amplification of global warming. Previous studies have calculated the enhanced warming based mainly on the radiative effect of the methane itself, with smaller contributions from the associated carbon dioxide or ozone increases. Here, we study the effect of strongly elevated methane (CH4) levels on oxidant and aerosol particle concentrations using a combination of chemistry-transport and general circulation models. A 10-fold increase in methane concentrations is predicted to significantly decrease hydroxyl radical (OH) concentrations, while moderately increasing ozone (O3). These changes lead to a 70% increase in the atmospheric lifetime of methane, and an 18% decrease in global mean cloud droplet number concentrations (CDNC). The CDNC change causes a radiative forcing that is comparable in magnitude to the longwave radiative forcing ("enhanced greenhouse effect") of the added methane. Together, the indirect CH4-O3 and CH4-OH-aerosol forcings could more than double the warming effect of large methane increases. Our findings may help explain the anomalously large temperature changes associated with historic methane releases.
Polar mesosphere summer echo strength in relation to solar variability and geomagnetic activity during 1997–2009
Authors: Smirnova M. , Belova E. , Kirkwood S.
Published: March 2011

Abstract. This paper is based on measurements of Polar Mesosphere Summer Echoes (PMSE) with the 52 MHz radar ESRAD, located near Kiruna, in Northern Sweden, during the summers of 1997–2009. Here, a new independent calibration method allowing estimation of possible changes in antenna feed losses and transmitter output is described and implemented for accurate calculation of year-to-year variations of PMSE strength (expressed in absolute units – radar volume reflectivity η). The method is based on radar-radiosonde comparisons in the upper troposphere/lower stratosphere region simultaneously with PMSE observations. Inter-annual variations of PMSE volume reflectivity are found to be strongly positively correlated with the local geomagnetic K-index, both when averaged over all times of the day, and when considering 3-h UT intervals separately. Increased electron density due to energetic particle precipitation from the magnetosphere is suggested as one of the possible reasons for such a correlation. Enhanced ionospheric electric field may be another reason but this requires further study. Multi-regression analysis of inter-annual variations of PMSE η shows also an anti-correlation with solar 10.7 cm flux and the absence of any statistically significant trend in PMSE strength over the interval considered (13-years). Variations related to solar flux and K-index account for 86% of the year-to-year variations in radar volume reflectivity.
Uncertainty in water resources availability in the Okavango River basin as a result of climate change
Authors: Hughes D. A. , Kingston D. G. , Todd M. C.
Published: March 2011

Abstract. This paper assesses the hydrological response to scenarios of climate change in the Okavango River catchment in Southern Africa. Climate scenarios are constructed representing different changes in global mean temperature from an ensemble of 7 climate models assessed in the IPCC AR4. The results show a substantial change in mean flow associated with a global warming of 2 °C. However, there is considerable uncertainty in the sign and magnitude of the projected changes between different climate models, implying that the ensemble mean is not an appropriate generalised indicator of impact. The uncertainty in response between different climate model patterns is considerably greater than the range due to uncertainty in hydrological model parameterisation. There is also a clear need to evaluate the physical mechanisms associated with the model projected changes in this region. The implications for water resource management policy are considered.
Quantifying the uncertainty in estimates of surface- atmosphere fluxes through joint evaluation of the SEBS and SCOPE models
Authors: Timmermans J. , van der Tol C. , Verhoef A. , Verhoef W. , Su Z. , van Helvoirt M. , Wang L.
Published: March 2011

Abstract. Accurate estimation of global evapotranspiration is considered of great importance due to its key role in the terrestrial and atmospheric water budget. Global estimation of evapotranspiration on the basis of observational data can only be achieved by using remote sensing. Several algorithms have been developed that are capable of estimating the daily evapotranspiration from remote sensing data. Evaluation of remote sensing algorithms in general is problematic because of differences in spatial and temporal resolutions between remote sensing observations and field measurements. This problem can be solved by using Soil Vegetation Atmosphere Transfer (SVAT) models, because on the one hand these models provide evapotranspiration estimations also under cloudy conditions and on the other hand can scale between different spatial resolutions. In this paper, the Soil Canopy Observation, Photochemistry and Energy fluxes (SCOPE) model is used for the evaluation of the Surface Energy Balance System (SEBS) model. SCOPE was employed to simulate remote sensing observations and to act as a validation tool. The advantages of the SCOPE model in this validation are (a) the temporal continuity of the data, and (b) the possibility of comparing different components of the energy balance. The SCOPE model was run using data from a whole growth season of a maize crop. It is shown that the original SEBS algorithm produces significant uncertainties in the turbulent flux estimations due to the misparameterizations of the ground heat flux and sensible heat flux. In the original SEBS formulation the fractional vegetation cover is used to calculate the ground heat flux. As this variable saturates very fast for increasing LAI, the ground heat flux is underestimated. It is shown that a parameterization based on LAI greatly reduces the estimation error over the season from RMSE = 25 W m−2 to RMSE = 18 W m−2. The uncertainties in the sensible heat flux arise due to a misparameterization of the roughness height for heat. In the original SEBS formulation the roughness height for heat is only valid for short vegetation. An additional parameterization for tall vegetation was implemented in the SEBS algorithm to correct for this. This improved the correlation between the latent heat flux predicted by the SEBS and the SCOPE algorithm from −0.05 to 0.69, and led to a decrease in error from 123 W m−2 to 94 W m−2 for the latent heat, with SEBS latent heat being consistently lower than the SCOPE reference. In addition the stability of the evaporative fraction was investigated.
Advanced radar-interpretation of InSAR time series for mapping and characterization of geological processes
Authors: Cigna F. , Del Ventisette C. , Liguori V. , Casagli N.
Published: March 2011

Abstract. We present a new post-processing methodology for the analysis of InSAR (Synthetic Aperture Radar Interferometry) multi-temporal measures, based on the temporal under-sampling of displacement time series, the identification of potential changes occurring during the monitoring period and, eventually, the classification of different deformation behaviours. The potentials of this approach for the analysis of geological processes were tested on the case study of Naro (Italy), specifically selected due to its geological setting and related ground instability of unknown causes that occurred in February 2005. The time series analysis of past (ERS1/2 descending data; 1992–2000) and current (RADARSAT-1 ascending data; 2003–2007) ground movements highlighted significant displacement rates (up to 6 mm yr−1) in 2003–2007, followed by a post-event stabilization. The deformational behaviours of instable areas involved in the 2005 event were also detected, clarifying typology and kinematics of ground instability. The urban sectors affected and unaffected by the event were finally mapped, consequently re-defining and enlarging the influenced area previously detected by field observations. Through the integration of InSAR data and conventional field surveys (i.e. geological, geomorphologic and geostructural campaigns), the causes of instability were finally attributed to tectonics.
Lentiviral Vector Mediated Transgenesis
Authors: Barde Isabelle , Verp Sonia , Offner Sandra , Trono Didier
Published: March 2011

The genetic manipulation of rodents through the generation of fully transgenic animals or via the modification of selective cells or organs is a procedure of paramount importance for biomedical research, either to address fundamental questions or to develop preclinical models of human diseases. Lentiviral vectors occupy the front stage in this scene, as they can mediate the integration and stable expression of transgenes both in vitro and in vivo. Widely used to modify a variety of cells, including re‐implantable somatic and embryonic stem cells, lentiviral vectors can also be directly administered in vivo, for instance in the brain. However, perhaps their most spectacular research application is in the generation of transgenic animals. Compared with the three‐decade‐old DNA pronuclear injection technique, lentivector‐mediated transgenesis is simple, cheap, and highly efficient. Furthermore, it can take full advantage of the great diversity of lentiviral vectors developed for other applications, and thus allows for ubiquitous or tissue‐specific or constitutive or externally controllable transgene expression, as well as RNAi‐mediated gene knockdown. Curr. Protoc. Mouse Biol. 1:169‐184. © 2011 by John Wiley & Sons, Inc.
Formation of Ultrafine‐Grained Microstructure of Ti–6Al–4V Alloy by Hot Deformation of α′ Martensite Starting Microstructure
Authors: Matsumoto Hiroaki , Lee Sang‐Hak , Ono Yoshiki , Li Yunping , Chiba Akihiko
Published: March 2011

We have presented a formation of ultrafine‐grained microstructure (dα ≈ 0.2 µm) of industrial Ti–6Al–4V alloy produced by the hot compression of a sample with the acicular α′ martensite starting microstructure. The hot‐deformation behavior was different from the case of the conventional (α + β) starting microstructure, that is, the phase transformation of α′/(α + β) during hot working enhanced the microstructural conversion, especially under the conditions of a low temperature and a high‐strain rate.
Prospective evaluation of preoperative concern among patients considering endoscopic sinus surgery: initial validation
Authors: Brandt Michael G. , Rotenberg Brian W. , Yeung Jeff C. , Franklin Jason H. , Doyle Philip C.
Published: March 2011

Background

Patients considering surgery face many uncertainties and concerns. This investigation aimed to develop an objective assessment tool for characterizing the areas of greatest concern among patients considering endoscopic sinus surgery (ESS).

Methods

As part of validating a clinical measure concerning perioperative concerns, patients presenting with chronic rhinosinusitis with or without nasal polyposis were voluntarily recruited. A total of 30 individuals completed a novel 19‐item questionnaire during their initial clinical visit and again 3 days later. Outcomes included descriptive statistics and test‐retest reliability.

Results

Data suggest that patient responses did not vary with age or gender. The questionnaire demonstrated strong test‐retest reliability, with alpha values from 0.881 to 0.942. Between‐rater reliability was consistent, with an average intraclass correlation coefficient (ICC) of 0.913. No relationships between question order and patient response was identified.

Conclusion

Patients considering ESS have concerns that remain stable in the early preoperative period requiring surgeon‐initiated inquiry and counsel. This is the first study to evaluate preoperative patient concerns, and initially establishes the Western Surgical Concern Inventory‐ESS (WSCI‐ESS) as a means of ensuring adequate patient counseling and a method of evaluating perioperative patient education. © 2011 ARS‐AAOA, LLC.
A randomized trial examining the effect of pretreatment point‐of‐care computed tomography imaging on the management of patients with chronic rhinosinusitis symptoms
Authors: Tan Bruce K. , Chandra Rakesh K. , Conley David B. , Tudor Robin Smolak , Kern Robert C.
Published: March 2011

Background

Recent consensus statements on the diagnosis of chronic rhinosinusitis (CRS) now require endoscopic or radiographic evidence of paranasal sinus inflammation. The timing of point‐of‐care (POC) computed tomography (CT) scan in the workup of these patients remains to be elucidated, particularly when endoscopy is negative. The objective of this research was to prospectively evaluate 2 algorithms for the initial management of patients with symptoms of CRS who manifest a normal nasal endoscopic examination.

Methods

A total of 40 such patients were randomized to 1 of 2 pathways: POC‐CT at the initial visit followed by medical therapy based upon CT results (pre‐CT group; n = 20), or empiric medical therapy (EMT) followed by POC posttreatment CT if symptoms persisted (EMT group; n = 20).

Results

The 2 groups were demographically and symptomatically similar with regard to 2003 Task Force major criteria. Otolaryngology follow‐up was recommended in 11 of 20 pre‐CT patients, all of whom (100%) returned. In contrast, only 10 of 20 EMT patients (50%) followed up as instructed (p < 0.05). Radiographic confirmation of CRS was found in 8 of 20 pre‐CT patients, and only 2 of 9 patients after EMT (p = 0.61). EMT patients received more antibiotic prescriptions (relative ratio [RR], 2.50; 95% CI, 1.46–4.27), while pre‐CT patients received more CT scans (RR, 2.22; 95% CI, 1.37–3.61). Overall prescriptions costs were similar to the EMT group ($253 vs $218; p = 0.37) and the overall number of otolaryngology visits was similar.

Conclusion

In patients with symptoms of CRS but negative endoscopy, POC at initial presentation results in substantially less unnecessary antibiotic prescriptions and significantly greater compliance with otolaryngology care but does result in a higher utilization of radiographic imaging. © 2011 ARS‐AAOA, LLC.
Antibacterial activity and antistatic composites of polyester/Ag‐SiO2 prepared by a sol–gel method
Authors: Wu Chin‐San , Liao Hsin‐Tzu
Published: March 2011

Poly(butylene adipate‐co‐terephthalate) (PBAT) composites containing silver‐silica (Ag‐SiO2) were prepared using an in‐situ sol–gel process. Maleic anhydride‐grafted PBAT (PBAT‐g‐MA) and multihydroxyl‐functionalized Ag‐SiO2 were used to improve the compatibility and dispersibility of Ag‐SiO2 within the PBAT matrix. The composites were characterized morphologically using transmission electron microscopy and chemically using Fourier transform infrared spectrometry. The existence of Ag‐SiO2 nanoparticles on the substrate was confirmed by the ultraviolet–visible absorption spectra. The antibacterial and antistatic properties of the composites were evaluated whether SiO2 enhanced the electrical conductivity was tested as well as whether Ag enhanced the antibacterial activity of the PBAT‐g‐MA/SiO2 or PBAT/SiO2 composites. The PBAT‐g‐MA/SiO2 or PBAT/SiO2 composite that contained Ag had better antibacterial activity (more than 1.3‐fold). The functionalized PBAT‐g‐MA/Ag‐SiO2 composite can markedly enhanced antibacterial and antistatic properties due to the carboxyl groups of maleic anhydride, which acted as coordination sites for the Ag‐SiO2 phase, allowing the formation of stronger chemical bonds. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Probing molecular mobility during crosslinking process of commercial resins by NMR multiexponential relaxation data analysis
Authors: de L. Campello Sérgio , de Souza Ricardo E. , de Azevedo Walter M.
Published: March 2011

In this study, we present the experimental results for the crosslinking process of a commercial polyester resin based on measurements of the spin lattice relaxation time T1 of protons, as function of the crosslinking time evolution. Multiexponential decomposition of the evolution of magnetization measured in inversion‐recovery experiments is performed. The population of “rigid” and “mobile” nuclear spin sites was estimated as function of time evolution. In analogy to the usual monomer conversion u, site conversion from “mobile” to “rigid” sites uM were also estimated as a function of time evolution and initial concentrations of the reagents. The multiexponential decomposition approach of T1 relaxation data allows one to follow crosslinking processes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Biodegradability studies on natural fibers reinforced polypropylene composites
Authors: Chattopadhyay Sanjay K. , Singh Sanjay , Pramanik Nilay , Niyogi U. K. , Khandal R. K. , Uppaluri Ramagopal , Ghoshal Aloke K.
Published: March 2011

Various composites of polypropylene (PP) produced using natural fibers such as pineapple leaf fiber, banana fiber, and bamboo fiber were studied for their degree and rate of aerobic biodegradation. Composites used contained 10, 15, and 50% volume fractions of pineapple leaf fiber, banana fiber, and bamboo fiber, respectively, which are the optimum fiber percentages of the respective composites as reported by these authors in their previous works. Cellulose has been used as positive reference material. All the composites exhibited partial biodegradation in the range of 5–15% depending on the fiber content. Degradation had not taken place in the covalent ester linkages between the natural fiber and the MA‐g‐PP compatibilizer but in those areas of the fibers which have remained only physically embedded in the resin matrix. Thus, although natural fibers reinforced PP composites are not excellent biodegradable material, they can address to the management of waste plastics by reducing the amount of polymer content used that in turn will reduce the generation of nonbiodegradable polymeric wastes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Evaluation of chitosan and their self‐assembled nanoparticles with pDNA for the application in gene therapy
Authors: Sarkar Kishor , Srivastava Rishi , Chatterji Urmi , Kundu P. P.
Published: March 2011

The molecular weight (MW) of chitosan (CS) was determined by viscometric method (using Mark‐Houwink equation) as well as by gel permeation chromatography, and the degree of deacetylation (DDA) of CS was measured by potentiometric titration method and Gran‐type linearization method. The values of DDA were obtained ∼ 83% (by potentiometric titration method) and ∼ 86% (by Gran‐type linearization method). The self‐assembled nanoparticles of CS/plasmid DNA (pDNA) complex were prepared by varying the concentration of CS. The formation of CS/pDNA complex was confirmed by 0.8% agarose gel electrophoresis and the particle size of the self‐assembled nanoparticle was determined by dynamic light scattering, atomic force microscopy and scanning electron microscopy. The stability of CS/pDNA complexes was determined by turbidity test with the help of UV‐Vis spectroscopy. The effect of ionic strength on the complexes was also observed by means of fluorescence spectroscopy. The cytotoxicity of CS on the HeLa cell line was observed by absorbance of MTT (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay and showed that CS has lower cytotoxicity in HeLa cells compared with that of poly (L‐lysine) in 293T cells. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electrical and thermal conductivity and tensile and flexural properties: Comparison of carbon black/polycarbonate and carbon nanotube/polycarbonate resins
Authors: King Julia A. , Via Michael D. , King Michelle E. , Miskioglu Ibrahim , Bogucki Gregg R.
Published: March 2011

Adding conductive carbon fillers to thermoplastic polymers increases the resulting composite's electrical conductivity. Carbon black (CB) is very effective at increasing composite electrical conductivity at low loading levels. In this study, varying amounts (2 to 10 wt %) CB were added to polycarbonate (PC) and the resulting composites were tested for electrical conductivity (1/electrical resistivity), thermal conductivity, and tensile and flexural properties. These results were compared with prior work done for carbon nanotubes (CNT) in polycarbonate. The percolation threshold was ∼ 2.3 vol % CB compared to between 0.7 and 1.4 vol % CNT. At 8 wt % filler, the CNT/PC composite had an electrical resistivity of 8 ohm‐cm compared to 122 ohm‐cm for the CB/PC composite. The addition of CB to polycarbonate increased the composite electrical and thermal conductivity and tensile and flexural modulus. The 8 wt % (5.5 vol %) CB in polycarbonate composite had a good combination of properties for semiconductive applications. Ductile tensile behavior is noted in pure polycarbonate and in samples containing up to 8 wt % CB. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Study of optical losses in poly(3‐octylthiophene) planar and inverted RIB waveguides
Authors: Messaad Khalida , Charrier Joël , Mosqueron Alexandra , Bosc Dominique , Rochard Philippe
Published: March 2011

Poly(3‐octylthiophene), (P3OT) in addition to its electronics properties exhibits a high Kerr coefficient, n2, due to its third order nonlinear dielectric susceptibility. At the wavelength of 1550 nm, this coefficient n2 is one of the highest. So, this material should be suitable to build integrated all optical switching devices. To construct this device, it is necessary to make a single‐mode optical waveguide. For the time being, such a P3OT waveguide has never been obtained due to excessive optical losses. In view to produce single‐mode waveguide with P3OT as a core, we investigated the different causes of these optical losses in the material and in the guiding structure. We characterized the optical transmission at key steps in its development. First, we demonstrated that the intrinsic polymer absorption is not a limiting factor at 1550 nm, and then we studied the transmission properties of planar (1‐D confined light) and channel waveguides (2‐D confined light). The results revealed that better transmission properties can be achieved using planar waveguides rather that confined channel waveguides. This article describes the development and the characterization of the guiding structures that enabled us to identify the main origins of optical losses. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Rationale and design of the randomized, multicenter EREMUS trial, a study that investigates how to achieve low restenosis and early reendothelialization after percutaneous coronary interventions
Authors: Cortese Bernardo , Danzi Gian Battista , Pitì Antonino , Severi Silva , Limbruno Ugo
Published: March 2011

Background: Drug eluting stent (DES) use has improved clinical outcome after percutaneous coronary interventions. However, DES‐treated patients may have a higher risk of stent thrombosis, mainly due to uncorrect stent deployment or lack of reendothelialization. Thus, the availabilily of different approaches with comparable efficacy to DES, but higher safety, especially in bleeding‐prone patients, have to be investigated. Study Design: The EREMUS is a multicenter open‐label prospective randomized three‐arm clinical trial that will investigate the efficacy of a paclitaxel coated balloon + an endothelial progenitor capture stent for the treatment of native coronary lesions, and compare it to a DES strategy, or the sole endothelial progenitor capture stent. An angiographic follow‐up with optical coherence tomography analysis will be scheduled 9 months after index procedure. Noninferiority regarding the primary endpoint (late luminal loss) between study group and DES is hypothesized. All patients will undergo clinical follow‐up until 24 months from index hospitalization. Conclusions: The EREMUS trial will determine whether a composite approach with a paclitaxel coated balloon + an endothelial progenitor capture stent in coronary lesions at medium‐to‐high risk of restenosis will achieve similar results compared to DES regarding inhibition of intrastent proliferation; complete stent strut reendothelialization, a safety issue, will also be investigated. © 2011 Wiley‐Liss, Inc.
Aortic valve perforation during aortic valvuloplasty
Authors: Ussia Gian Paolo , Sarkar Kunal , Tamburino Corrado
Published: March 2011

Balloon aortic valvuloplasty has seen a revival in interest because of its role in predilation and preparation of the annulus before trans catheter aortic valve implantation. Aortic valve cusp perforation is a serious complication that needs early recognition and prompt corrective measures to prevent a poor procedural outcome or conversion to emergent surgery. A number of useful angiographic and technical findings can alert the operator about the possibility of this complication. Failure to recognize cusp perforation can lead to serious procedural complications like severe aortic regurgitation, suboptimal prosthesis deployment, and function that can necessitate emergent open cardiac surgery © 2011 Wiley‐Liss, Inc.
Supported percutaneous coronary intervention using a novel 6‐Fr intra‐aortic balloon pump catheter via the brachial artery in a nonagenarian patient with an abdominal aortic aneurysm
Authors: Takahashi Akihiko , Taniguchi Norimasa
Published: March 2011

Intra‐aortic balloon pump (IABP) counterpulsation is a useful hemodynamic assist device during complex percutaneous coronary intervention (PCI) in patients with poor left ventricular function; however, the presence of an abdominal aortic aneurysm poses a problem, because insertion via the femoral artery may cause distal embolism and aneurysm rupture. A 92‐year‐old man with unstable angina was admitted to our hospital. Coronary angiography revealed chronic total occlusion of the proximal left anterior descending artery and severe stenosis of the left circumflex artery (LCX). The left ventricular ejection fraction was 36%. He also had an infrarenal abdominal aortic aneurysm with a diameter of 55 mm. Supported PCI was performed for the management of the LCX lesion. A novel 6‐Fr IABP catheter was inserted via the left brachial artery. The lesion was successfully dilated, and a 3.0 × 13 mm Cypher® stent was placed. After the PCI procedure, the IABP catheter was retrieved in the catheter laboratory, and the patient was discharged after 7 days. When a femoral approach is contraindicated in PCI, 6‐Fr IABP catheter insertion via the brachial artery is feasible and effective. © 2011 Wiley‐Liss, Inc.
Percutaneous coronary intervention of left main pseudoaneurysm with customized covered stents
Authors: Dhakam Sajid , Ahmeed Hafeez , Jafarani Asif
Published: March 2011

Left main pseuodaneurysm is a rare entity and is one of the potentially lethal consequences of coronary artery dissection. We describe a case of a young woman who almost a week after her delivery developed spontaneous left main dissection, manifested as acute anterior myocardial infarction. Left on medical treatment alone over a month, spontaneous dissection progressed to symptomatic large left main pseuodaneurysm, which was treated percutaneously with covered stents. © 2011 Wiley‐Liss, Inc.
Transhepatic portal vein access for balloon dilation of right upper pulmonary vein stenosis following infradiaphragmatic total anomalous pulmonary venous drainage repair
Authors: Tzifa Aphrodite , Ahmed Irfan , Rosenthal Eric
Published: March 2011

Transhepatic cardiac catheterization is now a well‐established alternative when conventional venous routes for cardiac access have failed. Some operators prefer this route even routinely, due to the direct access that it offers to the right atrium and atrial septum. We report the case of a newborn baby previously operated on for infradiaphragmatic total anomalous pulmonary venous drainage who represented with right sided pulmonary vein stenosis. Transhepatic portal vein access, first reported here, gave direct access to the right upper pulmonary vein, through the patent descending vein, after the conventional transfemoral venous and retrograde arterial routes had failed. © 2011 Wiley‐Liss, Inc.
Direct stenting compared to balloon predilation in drug‐eluting stents
Authors: Abbott J. Dawn , Earl Thomas , Vlachos Helen E. , Selzer Faith , Vaidya Kedarnath A. , Romero Alicia , Kip Kevin E. , Williams David O.
Published: March 2011

Objectives: We sought to examine the determinants and outcomes of direct stenting (DS) compared to predilation with drug‐eluting stents (DES). Background: Limited data suggest that DS with DES is feasible and may reduce restenosis compared to predilation. Whether DS improves clinical outcomes in unselected patients treated with DES is unknown. Methods: DEScover is a prospective, multicenter, observational study of percutaneous coronary intervention that enrolled patients in 2005. The analysis cohort included 4,210 patients who received a DES and had a single lesion treated with DS (n = 1,651) or predilation (n = 2,559) at the discretion of the operator. Multivariable analysis was performed for 1‐year outcomes. Results: DS was performed in 39.2% of patients. The direct stent patients were younger, less often male, and had a lesser extent of CAD. DS was performed less often in patients presenting with an acute myocardial infarction (MI) and more often in stable angina and elective procedures. Lesion characteristics differed with DS performed less often for calcified lesions, high‐grade stenoses (>90%), and bifurcation lesions. Lesion postdilation was less common in direct stent patients (42.1% vs. 50.7%, P = 0.0001). Complete procedural success was similar (99.8% vs. predilation 99.7%, P = 0.46). At 1 year, there was no difference in the adjusted hazard ratios of death (0.67, 0.44–1.04, P = 0.08), MI (1.05, 0.66–1.67, P = 0.83), stent thrombosis (0.38, 0.13–1.14, P = 0.08), TLR (0.75, 0.48–1.17, P = 0.21), TVR (0.89, 0.64–1.23, P = 0.47), and major adverse coronary event (0.88, 0.71–1.09, P = 0.24). Conclusions: DS with DES is commonly performed in clinical practice and results in similar long‐term outcomes as predilation. © 2011 Wiley Periodicals, Inc
Double‐stent method
Authors: Visrodia Kavel , Matthews Ray , Shriki Jabi
Published: March 2011

Coronary artery aneurysm (CAA) is an uncommon and often incidental finding on coronary angiography but can present with symptoms related to myocardial ischemia. The most common etiology is atherosclerosis, accounting for over 50% of cases, but CAAs can also be congenital or secondary to percutaneous coronary artery revascularization procedures, inflammatory arterial diseases, connective tissue disorders, and perhaps drug‐eluting‐stent (DES) implantation. A current lack of uniform guidelines for their therapeutic management, especially in the setting of DES, leaves their optimum treatment somewhat controversial. Polytetrafluoroethylene‐covered stents have gained popularity in recent years for percutaneous treatment of CAAs; however, their failure to endothelialize is associated with increased risk of thromboocclusive events. We describe two symptomatic patients presenting with large CAAs, one forming after DES implantation, that we treated using the double‐stent method, in which one stent is placed within another. The intent is to reduce stent permeability across the aneurysm and promote blood stasis within it, thereby encouraging aneurysm thrombosis and meanwhile preserving the stents' ability to endothelialize. The immediate angiographic result revealed markedly reduced filling of the aneurysms and aneurysm thrombosis was later confirmed at follow‐up. Both patients have remained asymptomatic during at least 9 months of follow‐up. To the best of our knowledge, this is the first case report describing the use of the double‐stent method as an alternative to treat CAAs percutaneously.© 2011 Wiley‐Liss, Inc.
Changes in myocardial ischemic burden following percutaneous coronary intervention of chronic total occlusions
Authors: Safley David M. , Koshy Sindhu , Grantham J. Aaron , Bybee Kevin A. , House John A. , Kennedy Kevin F. , Rutherford Barry D.
Published: March 2011

Objectives: We assessed the potential for percutaneous coronary intervention (PCI) of a chronic total occlusion (CTO) to decrease myocardial ischemia and established objective criteria to predict post‐procedure improvement. Background: Optimal treatment for CTO of coronary arteries is controversial, and selection criteria for PCI of CTO are subjective. Methods: All patients undergoing CTO PCI at a single center between 2002 and 2007 were included if myocardial perfusion imaging (MPI) was performed within 12 ± 3 months before and a follow‐up study within 12 ± 3 months after PCI. Average summed difference scores were calculated and converted to percent ischemic myocardium to classify patients as having normal/minimal, mild, moderate, or severe ischemia. A significant improvement in ischemia following PCI was classified as an absolute ≥5% decrease in ischemic myocardium. Receiver operating characteristic (ROC) curves were used to identify ischemic thresholds predictive of decreased and increased ischemic burden on follow‐up MPI. Results: In 301 patients, average baseline ischemic burden was 13.1% ± 11.9% and decreased to 6.9% ± 6.5% (P < 0.001) during follow‐up. Overall, 53.5% of patients met criteria for improvement following PCI. These patients were more likely to be male, without diabetes, with CTO in the left anterior descending artery, and classified as having high ischemic burden at baseline. ROC analysis identified a baseline 12.5% ischemic burden as optimal in identifying those most likely to have a significantly decreased ischemic burden post‐PCI. Those with a baseline ischemic burden less than 6.25% were more likely to have an increased ischemic burden post‐PCI. Conclusions: Ischemic burden is reduced following CTO PCI, and the decrease is greater at high ischemic burden. A threshold of 12.5% ischemic burden is suggested as a criterion for performing PCI in the setting of CTO. © 2011 Wiley‐Liss, Inc.
Digitized microscopy in the diagnosis of bladder cancer
Authors: Marganski William A. , El‐Sirgany Costa Vanessa , Kilpatrick Michael W. , Tafas Triantafyllos , Yim Joon , Matthews Michael
Published: March 2011

BACKGROUND:

Fluorescent in situ hybridization (FISH) analysis of urine samples has proven to be a valuable adjunctive test to urine cytology for both diagnosis and monitoring recurrence of urothelial carcinoma. Automated FISH analysis has the potential to improve laboratory efficiency and to reduce interobserver and intraobserver variability, resulting in more accurate, reproducible, assay performance.

METHODS:

A total of 3200 slides containing urine specimens, hybridized with the UroVysion Bladder Cancer Kit (Abbott Molecular, Des Plaines, Illinois), a 4‐probe set for chromosomes 3, 7, 17, and 9p21, was evaluated at Acupath Laboratories. The slides were analyzed over a 7‐month period, using the Ikoniscope ‐ oncoFISH bladder Test System (Ikonisys, New Haven, Connecticut).

RESULTS:

Analysis included the incorporation of a “flagging” system developed by Acupath Laboratories to identify cases, based on specific criteria, likely to benefit from further manual review. By using US Food and Drug Administration (FDA)‐cleared scoring criteria, 96.3% of the slides could be reported directly from the automated scan, requiring no manual review of the slide. For the remaining 3.7% of the samples (all of which were very hypocellular), a manual review of each slide subsequently allowed diagnoses to be successfully reported. The average scan time was 31.7 minutes, and the average slide scan review time was 8.3 minutes.

CONCLUSIONS:

This study demonstrated the value of an automated approach to the analysis of FISH slides, affording the benefit of high‐throughput while providing the user with the necessary images and tools to quickly and accurately report a case. Cancer (Cancer Cytopathol) 2011;. © 2011 American Cancer Society.
High‐Resolution Electronic Spectroscopy of the BODIPY Chromophore in Supersonic Beam and Superfluid Helium Droplets
Authors: Stromeck‐Faderl Anja , Pentlehner Dominik , Kensy Uwe , Dick Bernhard
Published: March 2011

We present the fluorescence excitation and dispersed emission spectra of the parent compound of the boron dipyrromethene (BODIPY) dye class measured in a supersonic beam and isolated in superfluid helium nanodroplets. The gas‐phase spectrum of the isolated molecules displays many low‐frequency transitions that are assigned to a symmetry‐breaking mode with a strongly nonharmonic potential, presumably the out‐of‐plane wagging mode of the BF2 group. The data are in good agreement with transition energies and Franck–Condon factors calculated for a double minimum potential in the upper electronic state. The corresponding transitions do not appear in the helium droplet. This is explained with the quasi‐rigid first layer of helium atoms attached to the dopant molecule by van der Waals forces. The spectral characteristics are those of a cyanine dye rather than that of an aromatic chromophore.
Surface Temperature Measurement of Plasma Facing Components in Metallic Environment
Authors: Loarer Th.
Published: March 2011

In the vast majority of tokamaks equipped with carbon walls, IR system is routinely used both for physics analysis of plasma wall interaction and real time control of the Plasma facing components (PFCs). However, future tokamaks will be equipped with metallic walls and due to their low emissivity (ε ∼0.1 to 0.5), the contribution of the reflected flux in the total collected photon flux by the detector (camera) will not be negligible anymore and could be even dominant. Monitoring surface temperature of metallic PFCs, in the visible and/or infrared range, independently of the environment (reflected flux) and of the thermal transient events (ELMs, hot spots, overheated layers...) is essential for safety of the PFCs and a challenge for development of high performance plasma scenario.

The active pyrometry method proposed in this paper allows surface temperature measurements independently of reflected and parasitic fluxes. A local increase of the surface temperature (Δ T(t) ∼ 10 K) introduced by a pulsed or modulated source results in an additional component of the photon flux collected by the detector. A “simple” filtering of the signal delivered by the detector allows extracting the temporal flux which depends only on the variation of the emitted flux, the emissivity and Δ T(t). The ratio of simultaneous measurements at two different wavelengths leads to the elimination of Δ T(t), whilst the ratio of the emissivities appears. Assuming that this ratio is known (same hypothesis as for the bicolour pyrometry), the final ratio depends only on the surface temperature independently of the reflected and parasitic fluxes. Also, it is shown that for bicolour method, wavelengths far away one to each other lead to a higher dynamic of the signal ratio as a function of temperature which largely compensates the error resulting from a possible drift of the emissivity ratio. Finally, the extrapolation from a local measurement to 2D mapping is discussed both in terms of spatial resolution and of characteristic time (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sixteen‐Frame Interferometer for a Study of a Pinch Dynamics in PF‐1000 Device
Authors: Zielińska E. , Paduch M. , Scholz M.
Published: March 2011

Multiframe laser interferometer system for studies of rapidly varying processes in dense, high‐temperature plasma in plasma‐focus device is described. The setup of sixteen‐frame interferometer contains the Mach‐Zehnder system and the completely new, innovative beams separator which allows obtaining sixteen interferometric frames in one discharge. Each interferogram is recorded separately with the same linear size and quality. Delay from the first to the last frame is 220 ns. The result obtained using this system is given. It demonstrates its quality and suitability for investigations of dynamics of fast, irreproducible processes in PF‐1000 (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)