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INTRODUCTION: We aimed to assess the effect of Colonoscopy Skills Improvement (CSI) training on patient comfort and sedation-related complications during colonoscopy. METHODS: This retrospective cohort study was performed on 19 endoscopists practicing in a Canadian tertiary care center who completed CSI training between October 2014 and May 2016. Data from 50 procedures immediately prior to, immediately after, and eight months following CSI training were included for each endoscopist. The primary outcome variable was intraprocedural comfort, and secondary outcomes included intraprocedural hypotension and hypoxia. Data were extracted from an electronic medical record and analyzed using SPSS version 20.0. Univariate analysis and stepwise multivariable logistic regression were performed to determine if there was an association between patient comfort and CSI training. Predictors of these outcomes including patient age, gender, sedation use and dosing, procedure completion, quality of bowel preparation, endoscopist experience, and specialty were included in the analysis. RESULTS: 2533 colonoscopies were included in the study. The mean dose of sedatives was reduced immediately following CSI training and at 8 months for both Fentanyl (75.4 mcg v. 67.8 mcg v. 65.9 mcg, p < 0.001) and Midazolam (2.57 mg v. 2.27 mg v. 2.19 mg, p < 0.001). The percentage of patients deemed to have a comfortable exam improved following endoscopist participation in CSI training and remained improved at 8 months (55.1% v. 70.2% v. 69.8%, p < 0.001). No significant change in rates of intraprocedural hypoxia or hypotension were noted following CSI training. CONCLUSION: CSI training is associated with improved patient comfort and reduced sedation requirements during colonoscopy.
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Hipotensión , Comodidad del Paciente , Canadá , Colonoscopía/métodos , Humanos , Hipnóticos y Sedantes , Hipoxia , Estudios RetrospectivosRESUMEN
Novel spatial, temporal, and energetically resolved measurements of bremsstrahlung hard-x-ray (HXR) emission from runaway electron (RE) populations in tokamaks reveal nonmonotonic RE distribution functions whose properties depend on the interplay of electric field acceleration with collisional and synchrotron damping. Measurements are consistent with theoretical predictions of momentum-space attractors that accumulate runaway electrons. RE distribution functions are measured to shift to a higher energy when the synchrotron force is reduced by decreasing the toroidal magnetic field strength. Increasing the collisional damping by increasing the electron density (at a fixed magnetic and electric field) reduces the energy of the nonmonotonic feature and reduces the HXR growth rate at all energies. Higher-energy HXR growth rates extrapolate to zero at the expected threshold electric field for RE sustainment, while low-energy REs are anomalously lost. The compilation of HXR emission from different sight lines into the plasma yields energy and pitch-angle-resolved RE distributions and demonstrates increasing pitch-angle and radial gradients with energy.
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Experiments in the DIII-D tokamak show that fast-ion transport suddenly becomes stiff above a critical threshold in the presence of many overlapping small-amplitude Alfvén eigenmodes (AEs). The threshold is phase-space dependent and occurs when particle orbits become stochastic due to resonances with AEs. Above threshold, equilibrium fast-ion density profiles are unchanged despite increased drive, and intermittent fast-ion losses are observed. Fast-ion Dα spectroscopy indicates radially localized transport of the copassing population at radii that correspond to the location of midcore AEs. The observation of stiff fast-ion transport suggests that reduced models can be used to effectively predict alpha profiles, beam ion profiles, and losses to aid in the design of optimized scenarios for future burning plasma devices.
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We report the first observation of prompt neutral beam-ion losses due to nonresonant scattering induced by toroidal and reversed shear Alfvén eigenmodes in the DIII-D tokamak. The coherent losses are of full energy beam ions expelled from the plasma on their first poloidal orbit. The first-orbit loss mechanism causes enhanced, concentrated losses on the first wall exceeding nominal levels of prompt losses. The loss amplitude scales linearly with the mode amplitude. The data provide a novel and direct measure of the radial excursion or scatter of particles induced by individual modes and may shed light on the mechanism for the scattering of energetic particles in interstellar medium.
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From numerical simulation and analytical modeling it is shown that fast ions can resonate with plasma waves at fractional values of the particle drift-orbit transit frequency when the plasma wave amplitude is sufficiently large. The fractional resonances, which are caused by a nonlinear interaction between the particle orbit and the wave, give rise to an increased density of resonances in phase space which reduces the threshold for stochastic transport. The effects of the fractional resonances on spatial and energy transport are illustrated for an energetic particle geodesic acoustic mode but they apply equally well to other types of MHD activity.
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PURPOSE: Diffusion-weighted imaging (DWI) may improve the diagnostic performance of conventional breast magnetic resonance imaging (MRI). Diffusion tensor imaging (DTI) is an extension of DWI. If DTI-derived measurements are to be clinically useful, particularly for predicting and/or monitoring therapeutic effects, they must be robust and reliable. The purpose of this study was to assess intra- and interobserver reproducibility of DTI-derived fractional anisotropy (FA) and apparent diffusion coefficient (ADC) at 3.0 T. MATERIALS AND METHODS: This prospective study was approved by the Institutional Review Board, and participants provided written informed consent. Sixty normal contralateral breasts of 60 patients (28-85 years, median 57) were analysed with a DWI sequence following a standard MRI protocol. Four authors performed all postprocessing and analyses independently and in different sessions. The same authors, blinded to the initial results, repeated the image postprocessing and analysis 4 weeks after the initial session. RESULTS: Mean ADC and FA for DTI sequences were, respectively, 1.92±0.30 and 0.32±0.09. Intra- and interobserver agreement of the four radiologists for ADC and FA were good (acceptable). Kappa values for ADC were intra-R1=0.82; intra-R2=0.84; intra-R3=0.89; intra-R4=0.88; inter-R1-R2=0.73; inter-R1-R3=0.74; inter-R1-R4=0.81; inter-R2-R3=0.76; inter-R2-R4=0.77; inter-R3-R4=0.83. Kappa values for FA were intra-R1=0.60; intra-R2=0.72; intra-R3=0.84; intra-R4 = 0.66; inter-R1-R2=0.64; inter-R1-R3=0.69; inter-R1-R4=0.72; inter-R2-R3=0.80; inter-R2-R4=0.71; inter-R3-R4=0.73. Within-subject coefficient of variation was 15% for ADC and 30% for FA. Repeatability with α=0.05 was 0.37×10-3 mm(2)/s for ADC and 0.112 for FA. CONCLUSIONS: ADC and FA measurements obtained with DTI are reproducible and may be valid, reliable and sensitive to change. ADC values obtained with DTI are more reproducible than FA.
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Mama/anatomía & histología , Imagen de Difusión por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Anisotropía , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Valores de ReferenciaRESUMEN
Sperm whale trumpets are sounds only occasionally documented, with a well recognisable and stereotyped acoustic arrangement. This study investigated the acoustic features of the trumpets and the context in which these sounds were recorded, using acoustic data collected over 22 years, in the Pelagos Sanctuary area (North-Western Mediterranean Sea). Analysed trumpets (n = 230), recorded at the beginning of a dive after the whale fluke-up, comprised a series of acoustic units organized in short sequences. Acoustic parameters were derived for the entire trumpet and for each distinguishable unit in a trumpet. Overall, trumpet durations and their initial frequencies were higher in recordings collected when multiple whales were visually or acoustically detected in the observation area. The identity of 68 whales was assessed through photo-identification, with 29 individuals producing trumpets within and between years. The variability of the acoustic parameters appeared to be higher within the same individuals rather than between different individuals, suggesting an individual plasticity in composing and arranging units in a trumpet. Different click patterns were observed before and after the trumpets, with more complex sequences when (1) other whales were visually/acoustically detected, and (2) individuals were in suitable foraging sites (i.e., canyon areas). Trumpets were commonly followed or preceded by click patterns suited for communication, such as codas and/or slow clicks. Significant relations between the trumpet emission and the male-only long-range communication click pattern (i.e. slow clicks) emerged, supporting the hypothesis that a trumpet is a sound emitted by maturing/mature males in feeding grounds. This study provides the first evidence that trumpets were conserved in the sperm whale acoustic repertoire at the decadal timescale, persisting across years and individuals in the same area. This persistence may be functionally specific to foraging activities performed by males in a well-established feeding area.
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Cachalote/fisiología , Vocalización Animal/fisiología , Acústica , Animales , Geografía , Modelos Lineales , Modelos Logísticos , Masculino , Mar Mediterráneo , Espectrografía del SonidoRESUMEN
We report here for the first time the effectiveness of Reteporella bryozoan genus in the early stage of coralligenous reefs recolonization through the analysis of the settlement and the population size structure over a two-years period at two impacted and two control sites. Results highlighted how Reteporella spp. colonies strongly recolonized, from 2017 to 2019, the bare coralligenous reefs subjected to the Costa Concordia shipwreck and its related anthropogenic disturbances, notably increasing both their density and percentage coverage. We recorded differences in colony size among impacted and control sites. Overall, large-sized colonies were reported at impacted sites exclusively, where Reteporella settlement and growth patterns differed if compared to control areas. This study highlights implications for the maintenance of the ecological functions, for the recovery processes, and for the future ecological shifts affecting one of the most important Mediterranean coastal ecosystems, the coralligenous reefs.
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Antozoos , Briozoos , Animales , Arrecifes de Coral , Ecosistema , Densidad de PoblaciónRESUMEN
The Ion Cyclotron Emission (ICE) diagnostic on the DIII-D tokamak consists of two outboard midplane systems. In the first system, straps of an ion cyclotron range of frequencies antenna are configured as receiving antennas. For the second system, dedicated magnetic probes incorporated into the outer wall of carbon tiles have recently been restored. These systems collected a large set of radio frequency measurements in the 2015-2018 experimental campaigns by digitizing signals at 200 MSamples/s for â¼5 s per discharge. Each shot typically yields 32 GB of data; techniques for successful handling and analysis of this challengingly large dataset are discussed. The raw voltage fluctuations (<0.2 V and <1 mW) are analyzed in frequency space via fast Fourier transforms. Signals can be analyzed between 1 and 200 MHz with appropriate filtering and aliasing; this frequency range is limited by DC breaks used to provide 5 kV DC isolation. These high-frequency signals are driven by energetic ions and electrons. In particular, energetic-ion-driven ICE occurs at harmonics of the ion cyclotron frequency, enabling the frequency to be mapped to lab space via equilibrium reconstruction. In many DIII-D plasmas, ICE is emitted from the radial center of the plasma.
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Preschoolers play an important role in the transmission of influenza, and suffer significant morbidity. Paediatric vaccination could prevent serious outcomes and offer broader societal benefits. This study explored parental views on influenza and paediatric vaccination and determined the uptake of a nursery-based vaccination programme for infants aged 6-23 months. Children were offered two doses of inactivated vaccine in 2004/05, and a single dose at the start of the 2005/06 season. An uptake rate of 11% (60/535) was achieved with 83% (50/60) of participants completing the programme. Semi-structured interviews were conducted with 10 parents. Thematic analysis of the data informed the development of a questionnaire. This was distributed to 650 parents, with children aged 6-30 months attending one of the 18 supporting nurseries. A response rate of 13% (83/650) was achieved. The low uptake rate achieved in the programme and findings from the interviews/questionnaire suggest parents were not convinced about the seriousness of paediatric influenza. Indeed, over two-thirds (55/81) questioned the necessity for an annual vaccination. Parents found it difficult to differentiate influenza from other respiratory illnesses, and expressed concerns about the need for annual injections and vaccine safety. Paediatric vaccination to increase herd immunity was held in balance with the notion that children should only be vaccinated if they are the main beneficiaries. Parental education on the burden of childhood influenza, on the direct benefits of influenza vaccination, and on indirect benefits to society is a necessity for a successful paediatric vaccination programme.
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Guarderías Infantiles , Conocimientos, Actitudes y Práctica en Salud , Programas de Inmunización/estadística & datos numéricos , Gripe Humana/prevención & control , Costo de Enfermedad , Inglaterra , Encuestas de Atención de la Salud , Humanos , Lactante , Gripe Humana/economíaRESUMEN
Concern is growing that marine fauna can be affected by noise such as naval sonar, pile driving or geophysical surveys, among others. Literature reports a variety of animal reactions to human noise (from apparently null or negligible to strong). However, conclusive results on its effects on marine mammals at individual and population level are still lacking. In 2015, the Italian Environmental Impact Assessment Commission mandated seismic operators apply a standard scientific protocol comparing marine mammal presence before, during, and after offshore seismic survey. For 60days before and after the survey, marine mammals are monitored using visual and acoustic methods. One or more acoustic autonomous recorders, depending on area size, must also be deployed throughout the three phases for continuous monitoring. Consistent data gathered from many surveys will enable robust statistical analysis of results. Diffusion of this monitoring method internationally would improve the study of far-reaching, intense, low frequency noise.
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Acústica , Cetáceos , Ruido , Animales , Monitoreo del Ambiente , Italia , SonidoRESUMEN
A gamma ray camera is built for the DIII-D tokamak [J. Luxon, Nucl. Fusion 42, 614 (2002)] that provides spatial localization and energy resolution of gamma flux by combining a lead pinhole camera with custom-built detectors and optimized viewing geometry. This diagnostic system is installed on the outer midplane of the tokamak such that its 123 collimated sightlines extend across the tokamak radius while also covering most of the vertical extent of the plasma volume. A set of 30 bismuth germanate detectors can be secured in any of the available sightlines, allowing for customizable coverage in experiments with runaway electrons in the energy range of 1-60 MeV. Commissioning of the gamma ray imager includes the quantification of electromagnetic noise sources in the tokamak machine hall and a measurement of the energy spectrum of background gamma radiation. First measurements of gamma rays coming from the plasma provide a suitable testbed for implementing pulse height analysis that provides the energy of detected gamma photons.
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Autism spectrum disorders (ASD) are highly heterogeneous developmental conditions characterized by deficits in social interaction, verbal and nonverbal communication, and obsessive/stereotyped patterns of behavior and repetitive movements. Social interaction impairments are the most characteristic deficits in ASD. There is also evidence of impoverished language and empathy, a profound inability to use standard nonverbal behaviors (eye contact, affective expression) to regulate social interactions with others, difficulties in showing empathy, failure to share enjoyment, interests and achievements with others, and a lack of social and emotional reciprocity. In developed countries, it is now reported that 1%-1.5% of children have ASD, and in the US 2015 CDC reports that approximately one in 45 children suffer from ASD. Despite the intense research focus on ASD in the last decade, the underlying etiology remains unknown. Genetic research involving twins and family studies strongly supports a significant contribution of environmental factors in addition to genetic factors in ASD etiology. A comprehensive literature search has implicated several environmental factors associated with the development of ASD. These include pesticides, phthalates, polychlorinated biphenyls, solvents, air pollutants, fragrances, glyphosate and heavy metals, especially aluminum used in vaccines as adjuvant. Importantly, the majority of these toxicants are some of the most common ingredients in cosmetics and herbicides to which almost all of us are regularly exposed to in the form of fragrances, face makeup, cologne, air fresheners, food flavors, detergents, insecticides and herbicides. In this review we describe various scientific data to show the role of environmental factors in ASD.
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Trastorno del Espectro Autista/etiología , Exposición a Riesgos Ambientales , Contaminantes Ambientales/efectos adversos , Sustancias Peligrosas/efectos adversos , Adolescente , Adulto , Trastorno del Espectro Autista/inducido químicamente , Niño , Preescolar , Femenino , Feto/efectos de los fármacos , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana EdadRESUMEN
A new gamma ray imager (GRI) is developed to probe the electron distribution function with 2D spatial resolution during runaway electron (RE) experiments at the DIII-D tokamak. The diagnostic is sensitive to 0.5-100 MeV gamma rays, allowing characterization of the RE distribution function evolution during RE growth and dissipation. The GRI consists of a lead "pinhole camera" mounted on the DIII-D midplane with 123 honeycombed tangential chords 20 cm wide that span the vessel interior. Up to 30 bismuth germanate (BGO) scintillation detectors capture RE bremsstrahlung radiation for Pulse Height Analysis (PHA) capable of discriminating up to 20 000 pulses per second. Digital signal processing routines combining shaping filters are performed during PHA to reject noise and record gamma ray energy. The GRI setup and PHA algorithms will be described and initial data from experiments will be presented. A synthetic diagnostic is developed to generate the gamma ray spectrum of a GRI channel given the plasma information and a prescribed distribution function. Magnetic reconstructions of the plasma are used to calculate the angle between every GRI sightline and orient and discriminate gamma rays emitted by a field-aligned RE distribution function.
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The immediate and early effects of coronary artery reperfusion initiated 1 and 3 hours after coronary artery occlusion were evaluated by two-dimensional echocardiographic measurements of overall and regional left ventricular function. A total of 29 anesthetized open chest dogs underwent one of the following: 1 hour occlusion followed by reperfusion (Group I, n = 9), 3 hour occlusion followed by reperfusion (Group II, n = 12) or 5 hour occlusion without reperfusion (Group III, n = 8). Serial two-dimensional echocardiography was performed at baseline; at 1, 3 and 5 hours of coronary occlusion; within 5 minutes of reperfusion; and at 2 hours of reperfusion. After occlusion, all groups manifested significant (p less than 0.01) increases in left ventricular diastolic and systolic area and decreases in left ventricular area ejection fraction. With coronary reperfusion, there was no improvement in these global variables in Groups I and II. However, immediately after reperfusion, there was improvement in the regional extent of dysfunction (Group I, 138 +/- 35 to 66 +/- 62 degrees, p less than 0.05; Group II, 156 +/- 51 to 85 +/- 77 degrees, p less than 0.05) as well as improvement in the regional degree of dyskinesia (p less than 0.05). These regional improvements were transient and resolved by 2 hours of coronary reperfusion. This immediate rebound of function was not associated with the duration of coronary occlusion, hemodynamic variables or ultimate infarct size. Thus, in the anesthetized open chest dog model, coronary artery reperfusion at 1 or 3 hours produces an immediate but transient improvement in regional systolic myocardial function.
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Circulación Coronaria , Infarto del Miocardio/fisiopatología , Animales , Autorradiografía , Perros , Ecocardiografía , Ventrículos Cardíacos/fisiopatología , Hemodinámica , Infarto del Miocardio/patología , Perfusión , Factores de TiempoRESUMEN
We have used the technique of scanning force microscopy (SFM) for studying the interaction of the bacteria A. ferrooxidans with the surface of the mineral pyrite. These bacteria are important to study with regard to acidification of streams and the environmental impact of such acidification. A. ferrooxidans cells readily colonize the pyrite surface, forming a tight mineral seal between the cell and the pyrite substrate. These bacteria subsequently may grow under pH neutral conditions, biooxidizing the underlying pyrite; this process creates etch pits in the pyrite. On average, these etch pits are 1.2 microns in lateral dimension and approximately 220 nm deep.
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Acidithiobacillus/crecimiento & desarrollo , Hierro/metabolismo , Microscopía de Fuerza Atómica/métodos , Sulfuros/metabolismo , Acidithiobacillus/metabolismo , Acidithiobacillus/fisiología , Adhesión Bacteriana , Biodegradación Ambiental , Oxidación-ReducciónRESUMEN
The flip-flop producing a pulse proportional to the transit time of an ultrasonic burst between two piezoelectric crystals was often reset by transmission artefacts in sonomicrometers. A design improvement was made. The insertion of two monostable vibrators and one nand gate corrected the resetting caused by transmission artefacts. The new design produced a flip-flop pulse that was proportional to the transit time of the ultrasonic burst through the aorta. Ascending aortic diameter was monitored in unanaesthetised dogs for 6 to 8 weeks using the new design.
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Aorta/anatomía & histología , Ultrasonido/instrumentación , Ultrasonografía , Animales , Biometría , Perros , Electrónica Médica , Femenino , Masculino , Monitoreo Fisiológico/instrumentaciónRESUMEN
Neutral beam injection is used in tokamaks to heat, apply torque, drive non-inductive current, and diagnose plasmas. Neutral beam diagnostics need accurate spatial calibrations to benefit from the measurement localization provided by the neutral beam. A new technique has been developed that uses in situ measurements of neutral beam emission to determine the spatial location of the beam and the associated diagnostic views. This technique was developed to improve the charge exchange recombination (CER) diagnostic at the DIII-D tokamak and uses measurements of the Doppler shift and Stark splitting of neutral beam emission made by that diagnostic. These measurements contain information about the geometric relation between the diagnostic views and the neutral beams when they are injecting power. This information is combined with standard spatial calibration measurements to create an integrated spatial calibration that provides a more complete description of the neutral beam-CER system. The integrated spatial calibration results are very similar to the standard calibration results and derived quantities from CER measurements are unchanged within their measurement errors. The methods developed to perform the integrated spatial calibration could be useful for tokamaks with limited physical access.
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We describe an experimental setup for making precision measurements of relative ß-decay rates of (22)Na, (36)Cl, (54)Mn, (60)Co, (90)Sr, (133)Ba, (137)Cs, (152)Eu, and (154)Eu. The radioactive samples are mounted in two automated sample changers that sequentially position the samples with high spatial precision in front of sets of detectors. The set of detectors for one sample changer consists of four Geiger-Müller (GM) tubes and the other set of detectors consists of two NaI scintillators. The statistical uncertainty in the count rate is few times 0.01% per day for the GM detectors and about 0.01% per hour on the NaI detectors. The sample changers, detectors, and associated electronics are housed in a sealed chamber held at constant absolute pressure, humidity, and temperature to isolate the experiment from environmental variations. The apparatus is designed to accumulate statistics over many years in a regulated environment to test recent claims of small annual variations in the decay rates. We demonstrate that absent this environmental regulation, uncontrolled natural atmospheric pressure variations at our location would imprint an annual signal of 0.1% on the Geiger-Müller count rate. However, neither natural pressure variations nor plausible indoor room temperature variations cause a discernible influence on our NaI scintillator detector count rate.