Search results for "snow"

Cardiovascular responses to dynamic and static upper-body exercise in a cold environment in coronary artery disease patients

2021

Abstract Purpose Upper-body exercise performed in a cold environment may increase cardiovascular strain, which could be detrimental to patients with coronary artery disease (CAD). This study compared cardiovascular responses of CAD patients during graded upper-body dynamic and static exercise in cold and neutral environments. Methods 20 patients with stable CAD performed 30 min of progressive dynamic (light, moderate, and heavy rating of perceived exertion) and static (10, 15, 20, 25 and 30% of maximal voluntary contraction) upper body exercise in cold (− 15 °C) and neutral (+ 22 °C) environments. Heart rate (HR), blood pressure (BP) and electrocardiographic (ECG) responses were recorded an…

Study of Snowboard Sandwich Structures

2005

The aim of the present research is to extend the knowledge of mechanical properties both on single components and on complete structure employed for snowboard. Flexural and torsion tests are performed to acquire important comparison parameters between snowboard sandwich structures that differ for the core material employed (wood, PVC foam core). A simplified FEM model is proposed to simulate the flexural tests of the sandwich structure showing good predictive capability.

Production of zero energy radioactive beams through extraction across superfluid helium surface

2003

A radioactive Ra-223 source was immersed in superfluid helium at 1.2-1.7 K. Electric fields transported recoiled Rn-219 ions in the form of snowballs to the surface and further extracted them across the surface. The ions were focussed onto an aluminium foil and alpha particle spectra were taken with a surface barrier spectrometer. This enabled us to determine the efficiency for each process unambiguously. The pulsed second sound wave proved effective in enhancing the extraction of positive ions from the surface. Thus we offer a novel method for study of impurities in superfluid helium and propose this method for production of zero energy nuclear beams for use at radioactive ion beam facilit…

Growth, yield and fruit quality of 'Tropic Snow' peach on size-controlling rootstocks under dry Mediterranean climates

2013

Abstract A six-year trial was carried out to evaluate the vegetative and productive performance of low-chill, early-ripening ‘Tropic Snow’ peach grown on five peach × almond rootstocks, different for their vigor. The study was conducted in south-western Sicily using 45 V-trained peach trees planted in 2005 and grafted on GF677, the most common rootstock in Sicily, and four low-vigor rootstocks selected at the Department of Agricultural, Food and Environmental Sciences, University of Pisa, namely IS5/8 (Polluce), IS5/19 (Castore), IS5/23, and IS5/29. Trunk circumference, winter and summer pruning weight, total number and weight of fruits per tree, and major fruit quality traits were recorded…

The SMAP and Copernicus Sentinel 1A/B microwave active-passive high resolution surface soil moisture product

2019

Abstract Soil Moisture Active Passive (SMAP) mission of NASA was launched in January 2015. Currently, SMAP has an L-band radiometer and a defunct L-band radar with a rotating 6-m mesh reflector antenna. On July 7th, 2015, the SMAP radar malfunctioned and became inoperable. Consequently, the production of high-resolution active-passive soil moisture product got hampered, and only ~2.5 months (April 15th, 2015 to July 7th, 2015) of data remain available. Therefore, during the SMAP post-radar phase, many ways were examined to restart the high-resolution soil moisture product generation of the SMAP mission. One of the feasible approaches was to substitute the SMAP radar with other available SAR…

The SMAP mission combined active-passive soil moisture product at 9 km and 3 km spatial resolutions

2018

Abstract The NASA Soil Moisture Active Passive (SMAP) mission was launched on January 31st, 2015. The spacecraft was to provide high-resolution (3 km and 9 km) global soil moisture estimates at regular intervals by combining for the first time L-band radiometer and radar observations. On July 7th, 2015, a component of the SMAP radar failed and the radar ceased operation. However, before this occurred the mission was able to collect and process ~2.5 months of the SMAP high-resolution active-passive soil moisture data (L2SMAP) that coincided with the Northern Hemisphere's vegetation green-up and crop growth season. In this study, we evaluate the SMAP high-resolution soil moisture product deri…

Chinese immigrants’ occupational well-being in Finland : the role of paternalistic leadership

2018

Purpose The purpose of this paper is to enhance the understanding of paternalistic leadership behaviour in the Finnish organisational context by investigating its relationship with Chinese immigrant employees’ occupational well-being. Design/methodology/approach This research was based on a survey of 117 Chinese immigrants working in Finland. The snowball sampling method was adopted in the present research. Findings The findings show that the dimensions of paternalistic leadership, specifically benevolent leadership behaviour, can be influential in Chinese immigrant knowledge workers’ occupational well-being in the Finnish organisational context. Research limitations/implications Paternali…

Chemosensitizers of the multixenobiotic resistance in amorphous aggregates (marine snow): etiology of mass killing on the benthos in the Northern Adr…

1998

Periodically appearing amorphous aggregates, 'marine snow', are formed in the sea and if settled as mars on the sea bottom cause death of benthic metazoans. Especially those animals are killed which are sessile filter feeders, e.g, sponges, mussels, or Anthozoa. The etiology of the toxic principle(s) is not yet well understood. Gel-like marine snow aggregates occurred in the Northern Adriatic during summer 1997. Samples of these aggregates were collected during the period July to September and the outer as well as the inner zones were analyzed for (i) cell toxicity, and (ii) chemosensitizing activity of the multixenobiotic resistance (MXR)mechanism. Organic extracts were prepared an…

2014

Abstract. Dynamical and microphysical processes in pyroconvective clouds in mid-latitude conditions are investigated using idealized three-dimensional simulations with the Active Tracer High resolution Atmospheric Model (ATHAM). A state-of-the-art two-moment microphysical scheme building upon a realistic parameterization of cloud condensation nuclei (CCN) activation has been implemented in order to study the influence of aerosol concentration on cloud development. The results show that aerosol concentration influences the formation of precipitation. For low aerosol concentrations (NCN = 200 cm−3), rain droplets are rapidly formed by autoconversion of cloud droplets. This also triggers the f…

Model Analysis of Hydrometeor Scattering Effects on Free Space Near-Infrared Links

2012

A promising technology for peer-to-peer connections and urban area networks is represented by wireless communications through free space using optical carrier (Free Space Optics, FSO). This technology ensures high data rates, with relatively low error rates, low power consumption and inherent security. Nevertheless FSO links are quite sensitive to atmospheric condition. Fog droplets, but also raindrops and snowflakes, may introduce severe path attenuation which drastically reduces the channel availability. A parametric model to simulate droplets scattering effects over the FSO link in terms of extinction coefficient, albedo factor and asymmetry coefficient as function of the particle water …