Search results for "light"

Laboratory disruption of scaled astrophysical outflows by a misaligned magnetic field

2021

The shaping of astrophysical outflows into bright, dense, and collimated jets due to magnetic pressure is here investigated using laboratory experiments. Here we look at the impact on jet collimation of a misalignment between the outflow, as it stems from the source, and the magnetic field. For small misalignments, a magnetic nozzle forms and redirects the outflow in a collimated jet. For growing misalignments, this nozzle becomes increasingly asymmetric, disrupting jet formation. Our results thus suggest outflow/magnetic field misalignment to be a plausible key process regulating jet collimation in a variety of objects from our Sun’s outflows to extragalatic jets. Furthermore, they provide…

Blight Caused by Sclerotium rolfsii on Potted Ornamental Citrus in Sicily.

2019

Approximately 140,000 container-grown ornamental citrus plants are produced each year in the province of Catania (eastern Sicily). In the spring of 2006, a severe blight was observed in a commercial nursery in Catania on 2-month-old rooted cuttings of lemon (Citrus limon (L.) Burm.) and calamondin (× Citrofortunella mitis (Blanco) J. W. Ingram & H. E. Moore). Approximately 80% of the nursery stock of 2,000 cuttings was affected. Cuttings were grown in 7.5-cm2 pots made with compressed peat and wood pulp at 28 to 30°C with 95 to 100% relative humidity on benches in a greenhouse, The pot mix was composed of peat, perlite, and soil (2:1:2). Cuttings showed a dark brown necrotic lesion at …

"The wrathful sunset glared...": The Krakatoa Sunsets in Victorian Science and Art

2020

The eruption of Krakatoa on August 27, 1883 was an event both tragic and spectacular. Thousands of lives were lost; sea waves and atmospheric disturbances were detected around the globe. Billions of tons of volcanic ash were thrown into the atmosphere producing multi-coloured sunsets caused by the scattering of light by aerosol particles. The paper discusses the ways in which these so-called Krakatoa sunsets, which were experienced by most of the world, were reflected in Victorian scientific and artistic discourse. The accounts included in the section “Descriptions of the Unusual Twilight Glows in Various Parts of the World, in 1883–84” of the Royal Society report The Eruption of Krakatoa a…

2021

European children and adolescents spend most of their daily life and especially their school hours being sedentary which may increase their risk for chronic non-communicable diseases later in life. After the curriculum reform of Finnish basic education in 2014, most of the new or renovated comprehensive schools in Finland incorporate open and flexible classroom designs. Their open learning spaces may provide students opportunities to reduce sedentary behavior during school hours. Thus, waist-worn accelerometers were used to assess classroom-based sedentary time (ST), the number of breaks from sedentary time (BST), and physical activity (PA) among cross-sectional samples of 3rd and 5th grade…

2020

Introduction/Purpose: Physical activity and sedentary time may associate with physical fitness and body composition. Yet, there exists some observational studies that have investigated the associations of device-based measures of sedentary time and physical activity (PA) with cardiorespiratory fitness (CRF) and body composition but associations with muscular fitness (MF) are less studied.Methods: Objective sedentary time and physical activity was measured by a hip worn accelerometer from 415 young adult men (age: mean 26, standard deviation 7 years). Cardiorespiratory fitness (VO2max) (CRF) was determined using a graded cycle ergometer test until exhaustion. Maximal force of lower extremiti…

Protein diffusion through charged nanopores with different radii at low ionic strength

2014

[EN] The diffusion of two similar molecular weight proteins, bovine serum albumin (BSA) and bovine haemoglobin (BHb), through nanoporous charged membranes with a wide range of pore radii is studied at low ionic strength. The effects of the solution pH and the membrane pore diameter on the pore permeability allow quantifying the electrostatic interaction between the chargedpore and the protein. Because of the large screening Debye length, both surface and bulk diffusion occur simultaneously. By increasing the pore diameter, the permeability tends to the bulk self-diffusion coefficient for each protein. By decreasing the pore diameter, the charges on the pore surface electrostatically hinder …

Collective and self diffusion of PS microgels in solution as observed by thermal diffusion forced Rayleigh scattering

2007

Thermal diffusion in solutions of polystyrene micro-network spheres (microgels) in toluene has been studied by the holographic scattering technique of thermal diffusion forced Rayleigh scattering (TDFRS) and by photon correlation spectroscopy (PCS). Size distributions of microgels of different crosslink ratios are obtained from TDFRS measurements on dilute solutions at very low q-values around 4000cm−1. At low concentrations a single diffusive mode is observed and the diffusion coefficient increases with concentration. It is attributed to the collective diffusion of the microgels and the solvent. At high concentrations an additional slow mode appears whose diffusion coefficient decreases wi…

Three Liberal Conceptions of Self-Realization: Creativity, Authenticity and Flourishing

2018

The concept of self-realization, in its most contemporary sense, owes much to an idea, which arose with the Enlightenment, as the culmination of the process of the rebirth of the subject in the fifteenth century. However, the notion of self-realization is complex because it entails a combination of two apparently antagonistic elements: freedom and normativity. In this chapter, I intend to clarify this concept by examining the theses of three authors—J. S. Mill, Taylor and Nussbaum—in whose work the idea of self-realization appears in a significant way. The three philosophers underline some common elements that together with the concepts of project and imagination held by Ortega shed light o…

PROLISEAN: A New Security Protocol for Programmable Matter

2021

The vision for programmable matter is to create a material that can be reprogrammed to have different shapes and to change its physical properties on demand. They are autonomous systems composed of a huge number of independent connected elements called particles. The connections to one another form the overall shape of the system. These particles are capable of interacting with each other and take decisions based on their environment. Beyond sensing, processing, and communication capabilities, programmable matter includes actuation and motion capabilities. It could be deployed in different domains and will constitute an intelligent component of the IoT. A lot of applications can derive fro…

Study of dynamics ofD0→K−e+νeandD0→π−e+νedecays

2015

In an analysis of a 2.92 fb(-1) data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions B(D-0 -> K(-)e(+)nu(e)) = (3.505 +/- 0.014 +/- 0.033)% and B(D-0 -> pi(-)e(+)nu(e)) = (0.295 +/- 0.004 +/- 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element f(+)(K)(0)vertical bar V-cs vertical bar = 0.7172 +/- 0.0025 +/- 0.0035 and f(+)(pi)(0)vertical bar V-cd vertical bar = 0.1435 +/- 0.0018 +/- 0.0009. Combining these products with the values of vertical bar V-cs(d)vertical bar from the SM constrain…