Early and late results of surgery for Wolff-Parkinson-White syndrome

Surgical treatment for accessory atrioventricular connections was performed in 60 patients with Wolff-Parkinson-White syndrome between 1981 and 1986. The initial procedure successfully divided 69 of 73 pathways identified preoperatively, including 39 of 40 left free wall pathways, 23 of 24 posteroseptal pathways, six of seven right free wall pathways, and one of two anteroseptal pathways. Three additional pathways were identified for the first time during follow-up. The primary procedure was successful in curing 53 (88%) of the 60 patients and in dividing 69 (91%) of the total of 76 pathways. Subsequent procedures increased the overall clinical cure rate to 97%. The surgery was performed with low morbidity and no perioperative or late mortality. Patients were followed-up for a mean of 6.4 years (range four to nine years). No patient showed clinical or electrocardiographic evidence of recurrence of a pathway which had been divided surgically. We conclude that regardless of pathway site, surgical treatment carries a low risk and has a high probability of avoiding lifelong antiarrhythmic therapy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75341/1/j.1445-5994.1991.tb04698.x.pd

In Depth Insights into the Key Steps of Delamination of Charged 2D Nano Materials

Delamination is a key step to obtain individual layers from inorganic layered materials needed for fundamental studies and applications. For layered van-der-Waals materials like graphene the adhesion forces are small allowing for mechanical exfoliation, whereas for ionic layered materials like layered silicates the energy to separate adjacent layers is considerably higher. Quite counter intuitively, we show for a synthetic layered silicate (Na0.5-hectorite) that a scalable and quantitative delamination by simple hydration is possible for high and homogeneous charge density, even for aspect ratios as large as 20000. A general requirement is the separation of adjacent layers by solvation to a distance where layer interactions become repulsive (Gouy-Chapman length). Further hydration up to 34 nm leads to the formation of a highly ordered lamellar liquid crystalline phase (Wigner crystal). Up to 8 higher-order reflections indicate excellent positional order of individual layers. The Wigner crystal melts when the interlayer separation reaches the Debye length, where electrostatic interactions between adjacent layers are screened. The layers become weakly chargecorrelated. This is indicated by fulfilling the classical Hansen-Verlet and Lindeman criteria for melting. We provide insight into the requirements for layer separation and controlling the layer distances for a broad range of materials and outline an important pathway for the integration of layers into devices for advanced applications

TESTING DJI PHANTOM 4 PRO FOR URBAN GEOREFERENCING

The urban environment is dynamic and is constantly changing. In Brazil, it has been recently published a decree for urban land regulation for the cadastre – Decree No 9.310 of 2018 15 of March which fixes 8,0 centimeters as the maximum spherical positional error for vertex of an urban property stock being georeferenced by Global Navigation Satellite System – GNSS equipment or aerial orthophotograph. Nowadays it has been noticed a growing use of Unmanned Aircraft Vehicle System – UAVS for remote sensing. This work aims to test if the accuracy of orthophoto-mosaic from a small UAVS mapping data of an urban area for a parcel scale georeferencing is answering the new decree of urban land regulation for the cadastre. It is intended to check the number of Ground Control Points (GCPs) to reach the best quality in terms of geometric resolution according to the necessity of positional quality for the urban parcel georeferenced for the cadastre. As a final consideration, the results implied that mapping a small surveying area with small UAVS is worth, being a potential tool for georeferencing city blocks, and using 20 pairs of GCPs is enough to reach the quality of positional geometry adequate to the Brazilian legislation

Fate and effects of silver nanoparticles at the aquatic-terrestrial interface: A floodplain mesocosm experiment

The production volume of engineered inorganic nanoparticles (EINP) successively increased over the last years. Once released into the natural environment, these particles may change their size and surface properties in interaction with other substances. This is expected to control their mobility and their impact on biochemical processes. However, the underlying processes are not fully understood yet. Transformation processes and long-term fate of citrate-coated silver nanoparticles (Ag NP) were investigated in an innovative floodplain mesocosm, which was run with river Rhine water and natural soil from an adjacent floodplain for 33 weeks. Flooding events were simulated every three weeks. The Ag NP with a concentration of 5 mg L-1 were continuously introduced into the water for three weeks followed by a three-week period without spiking. Every third week the ecotoxicological impact of Ag NP was determined by means of Gammarus mortality and feeding assays. At the end of the experiment, the total Ag concentrations were measured in profiles of the floodplain soil and the sediment as well as in algae that developed in the mesocosm. The total Ag concentration in the aquatic phase in the main zone as well as in the floodplain fluctuated according to the periodic Ag NP pulse. Further, significant amounts of Ag accumulated in algae (up to 4.7 mg g-1) and exposed leaves (up to 170 μg g-1). However, for the applied experimental conditions we did neither observed mortality nor sublethal effects on Gammarus feeding activity. More than 40 % of the Ag remained in the sediment of the main zone and 7 % were transported during flooding into the floodplain soil. Furthermore, 0.5 % of the Ag was still in the water phase. Most of the particles were immobilized in the top layer of the sediments and soil. Only very little transport in deeper soil layers was observed in the soil columns and sediment. Accumulation in algae, sediment, and soil is alarming for long-term environmental impact assessments and the long lifetime in the aqueous phase suggests long-range transport of Ag NP in rivers

Measuring magnetic moments of polydisperse ferrofluids utilizing the inverse Langevin function

The dipole strength of magnetic particles in a suspension is obtained by a graphical rectification of the magnetization curves based on the inverse Langevin function. The method yields the arithmetic and the harmonic mean of the particle distribution. It has an advantage compared to the fitting of magnetization curves to some appropriate mathematical model: It does not rely on assuming a particular distribution function of the particles

Targeting quiescent leukemic stem cells using second generation autophagy inhibitors

In chronic myeloid leukemia (CML), tyrosine kinase inhibitor (TKI) treatment induces autophagy that promotes survival and TKI-resistance in leukemic stem cells (LSCs). In clinical studies hydroxychloroquine (HCQ), the only clinically approved autophagy inhibitor, does not consistently inhibit autophagy in cancer patients, so more potent autophagy inhibitors are needed. We generated a murine model of CML in which autophagic flux can be measured in bone marrow-located LSCs. In parallel, we use cell division tracing, phenotyping of primary CML cells, and a robust xenotransplantation model of human CML, to investigate the effect of Lys05, a highly potent lysosomotropic agent, and PIK-III, a selective inhibitor of VPS34, on the survival and function of LSCs. We demonstrate that long-term haematopoietic stem cells (LT-HSCs: Lin−Sca-1+c-kit+CD48−CD150+) isolated from leukemic mice have higher basal autophagy levels compared with non-leukemic LT-HSCs and more mature leukemic cells. Additionally, we present that while HCQ is ineffective, Lys05-mediated autophagy inhibition reduces LSCs quiescence and drives myeloid cell expansion. Furthermore, Lys05 and PIK-III reduced the number of primary CML LSCs and target xenografted LSCs when used in combination with TKI treatment, providing a strong rationale for clinical use of second generation autophagy inhibitors as a novel treatment for CML patients with LSC persistence

Removal of ecotoxicity of 17α-ethinylestradiol using TAML/peroxide water treatment

17α -ethinylestradiol (EE2), a synthetic oestrogen in oral contraceptives, is one of many pharmaceuticals found in inland waterways worldwide as a result of human consumption and excretion into wastewater treatment systems. At low parts per trillion (ppt), EE2 induces feminisation of male fish, diminishing reproductive success and causing fish population collapse. Intended water quality standards for EE2 set a much needed global precedent. Ozone and activated carbon provide effective wastewater treatments, but their energy intensities and capital/operating costs are formidable barriers to adoption. Here we describe the technical and environmental performance of a fast- developing contender for mitigation of EE2 contamination of wastewater based upon smallmolecule, full-functional peroxidase enzyme replicas called “TAML activators”. From neutral to basic pH, TAML activators with H2O2 efficiently degrade EE2 in pure lab water, municipal effluents and EE2-spiked synthetic urine. TAML/H2O2 treatment curtails estrogenicity in vitro and substantially diminishes fish feminization in vivo. Our results provide a starting point for a future process in which tens of thousands of tonnes of wastewater could be treated per kilogram of catalyst. We suggest TAML/H2O2 is a worthy candidate for exploration as an environmentally compatible, versatile, method for removing EE2 and other pharmaceuticals from municipal wastewaters.Heinz Endowments, the Swiss National Science Foundation, the Steinbrenner Institute for a Steinbrenner Doctoral Fellowship. NMR instrumentation at CMU was partially supported by NSF (CHE-0130903 and CHE-1039870)

Influence of operating parameters on the biodegradation of steroid estrogens and nonylphenolic compounds during biological wastewater treatment processes

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Environmental Science & Technology, copyright © American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/es901612v.This study investigated operational factors influencing the removal of steroid estrogens and nonylphenolic compounds in two sewage treatment works, one a nitrifying/denitrifying activated sludge plant and the other a nitrifying/denitrifying activated sludge plant with phosphorus removal. Removal efficiencies of >90% for steroid estrogens and for longer chain nonylphenol ethoxylates (NP4−12EO) were observed at both works, which had equal sludge ages of 13 days. However, the biological activity in terms of milligrams of estrogen removed per day per tonne of biomass was found to be 50−60% more efficient in the nitrifying/denitrifying activated sludge works compared to the works which additionally incorporated phosphorus removal. A temperature reduction of 6 °C had no impact on the removal of free estrogens, but removal of the conjugated estrone-3-sulfate was reduced by 20%. The apparent biomass sorption (LogKp) values were greater in the nitrifying/denitrifying works than those in the nitrifying/denitrifying works with phosphorus removal for both steroid estrogens and nonylphenolic compounds possibly indicating a different cell surface structure and therefore microbial population. The difference in biological activity (mg tonne−1 d−1) identified in this study, of up to seven times, suggests that there is the potential for enhancing the removal of estrogens and nonylphenols if more detailed knowledge of the factors responsible for these differences can be identified and maximized, thus potentially improving the quality of receiving waters.Public Utilities Board (Singapore), Anglian Water Ltd, Severn Trent Water Ltd, Thames Water Utilities Ltd, United Utilities 393 Plc and Yorkshire Water Services

Physical conditioning and mental stress reduction - a randomised trial in patients undergoing cardiac surgery

<p>Abstract</p> <p>Background</p> <p>Preoperative anxiety and physical unfitness have been shown to have adverse effects on recovery from cardiac surgery. This study involving cardiac surgery patients was primarily aimed at assessing the feasibility of delivering physical conditioning and stress reduction programs within the public hospital setting. Secondary aims were to evaluate the effect of these programs on quality of life (QOL), rates of postoperative atrial fibrillation (AF) and length of stay (LOS) in hospital.</p> <p>Methods</p> <p>Elective patients scheduled for coronary artery bypass graft and/or valve surgery at a public hospital in Melbourne, Australia were enrolled. Patients were randomized to receive either holistic therapy (HT) or usual care (UC). HT consisted of a series of light physical exercise sessions together with a mental stress reduction program administered in an outpatient setting for the first two weeks after placement on the waiting list for surgery. A self-administered SF-36 questionnaire was used to measure QOL and hospital records to collect data on LOS and rate of postoperative AF.</p> <p>Results</p> <p>The study population comprised 117 patients of whom 60 received HT and 57 received UC. Both programs were able to be delivered within the hospital setting but ongoing therapy beyond the two week duration of the program was not carried out due to long waiting periods and insufficient resources. HT, as delivered in this study, compared to UC did not result in significant changes in QOL, LOS or AF incidence.</p> <p>Conclusions</p> <p>Preoperative holistic therapy can be delivered in the hospital setting, although two weeks is insufficient to provide benefits beyond usual care on QOL, LOS or postoperative AF. Further research is now required to determine whether a similar program of longer duration, or targeted to high risk patients can provide measurable benefits.</p> <p>Trial registration</p> <p>This trial was conducted as part of a larger study and according to the principles contained in the CONSORT statement 2001.</p

Comparison of UVC/S₂O₈ ^2- with UVC/H₂O₂ in terms of efficiency and cost for the removal of micropollutants from groundwater

This study compared the UVC/S2O82- system with the more commonly used AOP in water industry, UVC/H2O2, and examined whether the first one can be an economically feasible alternative technology. Atrazine and 4 volatile compounds (methyl tert-butyl ether, cis-dichlorethen, 1,4-dioxane and 1,1,1-trichloroethane) were chosen as model contaminants because they exhibit different susceptibility to UVC photolysis and AOPs. A collimated beam apparatus was utilized for the majority of the experiments (controlled environment, without mass transfer phenomena), while selected experiments were performed in a flow-through reactor to simulate industrial applications. Initial experiments on the activation of oxidants with a LP lamp indicated that S2O82- is photolysed about 2.3times faster than H2O2 and that the applied treatment times were not sufficient to utilize the majority of the oxidant. The effect of oxidants' concentrations were tested with atrazine alone and in the micropollutants' mixture and it was decided to use 11.8mgL-1 S2O82- and 14.9mgL-1 H2O2 for further testing since is closer to industrial applications and to minimize the residual oxidant concentration. Changes of the matrix composition of the treated water were investigated with the addition of chloride, bicarbonate and humic acids at concentrations relevant to a well-water-sample, the results showed that the system least affected was UVC/H2O2. Only when bicarbonate was used, UVC/S2O82- performed better. Overall, testing these systems with the mixture of micropollutants gave better insights to their efficiency than atrazine alone and UVC/S2O82- is recommended for selective oxidation of challenging matrices