5,998 research outputs found

    Outcomes of conjunctival compression sutures for hypotony after glaucoma filtering surgery

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    3openopenQuaranta L.; Riva I.; Floriani I.C:Quaranta, Luciano; Riva, Ivano; Floriani I., C

    Ultra Low Momentum Neutron Catalyzed Nuclear Reactions on Metallic Hydride Surfaces

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    Ultra low momentum neutron catalyzed nuclear reactions in metallic hydride system surfaces are discussed. Weak interaction catalysis initially occurs when neutrons (along with neutrinos) are produced from the protons which capture ``heavy'' electrons. Surface electron masses are shifted upwards by localized condensed matter electromagnetic fields. Condensed matter quantum electrodynamic processes may also shift the densities of final states allowing an appreciable production of extremely low momentum neutrons which are thereby efficiently absorbed by nearby nuclei. No Coulomb barriers exist for the weak interaction neutron production or other resulting catalytic processes.Comment: 4 pages, ReVTeX forma

    Epithelial integrin alpha 6 beta 4: complete primary structure of alpha 6 and variant forms of beta 4.

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    The integrin alpha 6 beta 4 is a heterodimer predominantly expressed by epithelia. While no definite receptor function has yet been assigned to it, this integrin may mediate adhesive and/or migratory functions of epithelial cells. We have determined the complete primary structure of both the alpha 6 and beta 4 subunits from cDNA clones isolated from pancreatic carcinoma cell line libraries. The deduced amino acid sequence of alpha 6 is homologous to other integrin alpha chains (18-26% identity). Antibodies to an alpha 6 carboxy terminus peptide immunoprecipitated alpha 6 beta 4 complexes from carcinoma cells and alpha 6 beta 1 complexes from platelets, providing further evidence for the association of alpha 6 with more than one beta subunit. The deduced amino acid sequence of beta 4 predicts an extracellular portion homologous to other integrin beta chains, and a unique cytoplasmic domain comprised of greater than 1,000 residues. This agrees with the structures of the beta 4 cDNAs from normal epithelial cells (Suzuki, S., and Y. Naitoh. 1990. EMBO [Eur. Mol. Biol. Organ.] J. 9:757-763; Hogervost, F., I. Kuikman, A. E. G. Kr. von dem Borne, and A. Sonnenberg. 1990. EMBO [Eur. Mol. Biol. Organ.] J. 9:765-770). Compared to these structures, however, the beta 4 cDNAs that we have cloned from carcinoma cells contain extra sequences. One of these is located in the 5'-untranslated region, and may encode regulatory sequences. Another specifies a segment of 70 amino acids in the cytoplasmic tail. Amplification by reverse transcription-polymerase chain reaction of mRNA indicated that multiple forms of beta 4 may exist, possibly due to cell-type specific alternative splicing. The unique structure of beta 4 suggests its involvement in novel cytoskeletal interactions. Consistent with this possibility, alpha 6 beta 4 is mostly concentrated on the basal surface of epithelial cells, but does not colocalize with components of adhesion plaques

    Differences in the Same OMI/MLS Aura Tropospheric Ozone Data Set Published Before and After January 2013

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    On the website "NASA Goddard Homepage for Tropospheric Ozone", global data of tropospheric ozone obtained from observations of OMI and MLS Aura satellite instruments, are reported. In mid-2013, the data was covering the period between October 2004 and January 2013. Subsequently, in early 2014, the time series was extended until December 2013. At present time, the published series has been extended to December 2014. Analysing this new series, we observed that the data already published to January 2013 had been replaced; not only the missing months of 2013 were added but all the values published since 2004 were recalculated. We present the detected differences in the comparison between common data to both time series (the original, before January 2013, and the new one, currently published on the website). These differences are important considering that they represent the result of the same satellite observation and should be considered when comparing results before/after January 2013, especially when adopting a certain confidence level in the spectral analysis of these data to intraseasonal scale. A warn of caution is suggested in the use of these observations and intercomparison with other values of these and other instruments, because of possible recurrent problems of instrumental calibration.Fil: Cionco, Rodolfo Gustavo. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Agosta Scarel, Eduardo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Rodriguez, Rubén L.. Universidad Tecnológica Nacional; Argentina. Universidad Nacional de La Plata; ArgentinaFil: Quaranta, Nancy Esther. Universidad Nacional de La Plata; Argentina. Universidad Tecnológica Nacional; Argentin

    Prediction and Simulator Verification of Roll/lateral Adverse Aeroservoelastic Rotorcraft-Pilot Couplings

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    The involuntary interaction of a pilot with an aircraft can be described as pilot-assisted oscillations. Such phenomena are usually only addressed late in the design process when they manifest themselves during ground/flight testing. Methods to be able to predict such phenomena as early as possible are therefore useful. This work describes a technique to predict the adverse aeroservoelastic rotorcraft–pilot couplings, specifically between a rotorcraft’s roll motion and the resultant involuntary pilot lateral cyclic motion. By coupling linear vehicle aeroservoelastic models and experimentally identified pilot biodynamic models, pilot-assisted oscillations and no-pilot-assisted oscillation conditions have been numerically predicted for a soft-in-plane hingeless helicopter with a lightly damped regressive lead–lag mode that strongly interacts with the roll mode at a frequency within the biodynamic band of the pilots. These predictions have then been verified using real-time flight-simulation experiments. The absence of any similar adverse couplings experienced while using only rigid-body models in the flight simulator verified that the observed phenomena were indeed aeroelastic in nature. The excellent agreement between the numerical predictions and the observed experimental results indicates that the techniques developed in this paper can be used to highlight the proneness of new or existing designs to pilot-assisted oscillations

    Energy harvesting from electrospun piezoelectric nanowires for structural health monitoring of a cable-stayed bridge

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    Wireless monitoring could greatly impact the fields of structural health assessment and infrastructure asset management, but some technological challenges pose unsolved issues toward its reliable use in continuous large-scale applications. Among the others, it is worth highlighting that power supply by means of batteries is usually implemented within wireless sensor networks, even though it causes practical concerns that heavily prevent the development of efficient monitoring systems for large structures and infrastructures. Conversely, scavenging ambient energy can alleviate or eventually eliminate the problem of electrical supply by batteries, a strategy that has emerged in recent years as a promising technological solution for bridges. Within this framework, the present work proposes to harvest ambient-induced vibrations of bridge structures using a new class of piezoelectric textiles. The considered case study is an existing cable-stayed bridge located in Italy along the high-speed road that connects Rome and Naples, for which a recent monitoring campaign has allowed to record the dynamic responses of deck and cables. In order to enhance the electric energy that can be converted from wind- and traffic-induced bridge vibrations, the energy harvester exploits a piezoelectric nanogenerator built using arrays of piezoelectric electrospun nanofibers. Particularly, several fiber arrangements are studied at the nano/micro-scale leading to different macro constitutive laws and different electric energy output. A computational study is performed to demonstrate that such nanogenerator is able to provide higher energy levels from recorded dynamic loading time histories than a standard piezoelectric energy harvester. The feasibility of this piezoelectric nanogenerator for bridge monitoring applications is finally discussed

    Effects of the timolol-dorzolamide fixed combination and latanoprost on circadian diastolic ocular perfusion pressure in glaucoma.

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    PURPOSE. To evaluate the effect of the timolol-dorzolamide fixed combination (TDFC) and latanoprost 0.005% on 24-hour intraocular pressure (IOP), systolic (SBP) and diastolic (DBP) blood pressure, and diastolic ocular perfusion pressure (DOPP) in patients with primary open-angle glaucoma (POAG). METHODS. This was an institutional, randomized clinical trial. After a 24-hour assessment without treatment, 27 previously untreated patients with POAG were randomized to 6 weeks’ treatment with twice-daily TDFC (8 AM and 8 PM) followed by once-daily latanoprost 0.005% (8 PM), or vice versa. One eye was analyzed per patient. The mean values of IOP, DBP, SBP, and DOPP (difference between DBP and IOP) were recorded at each time point, and the 24-hour data are the mean values of each patient’s measurements over the 24-hour period. The differences between the values of the first treatment period and the baseline and the second treatment period and washout were calculated and analyzed by means of an analysis of variance model that tested the effects of sequence and treatment. RESULTS. Both treatments significantly reduced 24-hour IOP (P <0.0001), but TDFC led to lower 24-hour pressure (mean ±SD: 15.4 ±1.9 vs. 16.7± 1.7 mm Hg; P=0.004). Latanoprost did not lead to any significant reduction in mean 24-hour SBP and DBP (SBP: P =0.952; DBP: P=0.831), but TDFC did (SBP and DBP: P < 0.0001). Both treatments significantly increased 24-hour DOPP (P < 0.0001), with no difference between the two medications (P=0.09). CONCLUSIONS. In previously untreated patients with POAG, TDFC, and latanoprost equally enhanced 24-hour DOPP: the former by counteracting the decrease in DBP with a substantial reduction in IOP and the latter by not affecting DBP and significantly reducing IO

    The effect of posture on asynchronous chest wall movement in COPD

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    Priori R, Aliverti A, Albuquerque AL, Quaranta M, Albert P, Calverley PM. the effect of posture on asynchronous chest wall movement in COPD. J Appl Physiol 114: 1066-1075, 2013. First published February 14, 2013; doi:10.1152/japplphysiol.00414.2012.-Chronic obstructive pulmonary disease (COPD) patients often show asynchronous movement of the lower rib cage during spontaneous quiet breathing and exercise. We speculated that varying body position from seated to supine would influence rib cage asynchrony by changing the configuration of the respiratory muscles. Twenty-three severe COPD patients (forced expiratory volume in 1 s = 32.5 +/- 7.0% predicted) and 12 healthy age-matched controls were studied. Measurements of the phase shift between upper and lower rib cage and between upper rib cage and abdomen were performed with opto-electronic plethysmography during quiet breathing in the seated and supine position. Changes in diaphragm zone of apposition were measured by ultrasounds. Control subjects showed no compartmental asynchronous movement, whether seated or supine. in 13 COPD patients, rib cage asynchrony was noticed in the seated posture. This asynchrony disappeared in the supine posture. in COPD, upper rib cage and abdomen were synchronous when seated, but a strong asynchrony was found in supine. the relationships between changes in diaphragm zone of apposition and volume variations of chest wall compartments supported these findings. Rib cage paradox was noticed in approximately one-half of the COPD patients while seated, but was not related to impaired diaphragm motion. in the supine posture, the rib cage paradox disappeared, suggesting that, in this posture, diaphragm mechanics improves. in conclusion, changing body position induces important differences in the chest wall behavior in COPD patients.Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, ItalyUniversidade Federal de São Paulo, Dept Med, São Paulo, BrazilUniv Liverpool, Univ Hosp Aintree, Ctr Clin Sci, Liverpool L69 3BX, Merseyside, EnglandUniversidade Federal de São Paulo, Dept Med, São Paulo, BrazilWeb of Scienc
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