Total Energy Influx Research Articles

Three-dimensional diastolic blood flow in the left ventricle

Three-dimensional blood flow in a human left ventricle is studied via a computational analysis with magnetic resonance imaging of the cardiac motion. Formation, growth and decay of vortices during the myocardial dilation are analyzed with flow patterns on various diametric planes. They are dominated by momentum transfer during flow acceleration and deceleration through the mitral orifice. The posterior and anterior vortices form an asymmetric annular vortex at the mitral orifice, providing a smooth transition for the rapid inflow to the ventricle. The development of core vortex accommodates momentum for deceleration and for acceleration at end diastolic atrial contraction. The rate of energy dissipation and that of work done by viscous stresses are small; they are approximately balanced with each other. The kinetic energy flux and the rate of work done by pressure delivered to blood from ventricular dilation is well balanced by the total energy influx at the mitral orifice and the rate change of kinetic energy in the ventricle.

On the Impact of Electron Temperature in Magnetron Sputtering Benchmarked with Energy Flux Measurements

AbstractIn this work we have investigated the effect of increasing the electron energy as a way to increase the ionization probability of the sputtered metal (Ti) by measuring the impact of three different process gases (Ne, Ar, and Kr). Using a combined Langmuir and calorimetric probe we were able to compare the electron density ne, the electron temperature Te, the total energy influx, as well as the different energy flux contributions from charge carriers, neutrals and surface processes for various discharge conditions. The results show that the electron temperature can be increased by up to a factor of 3 by using Ne instead of Ar (or Kr). Furthermore, it was also found that by using Ne the mean free path for electron impact ionization was decreased by at least 50 %, and for higher pressures even more. In addition, we show that the contributions from sputtered neutrals and film formation represent a large fraction of the total energy influx, whereas the energy flux from ions is very low due to low ne in this type of discharge. However, by investigating changes in the electron energy flux, it was possible to study the effects of using Ne. These results may provide a way to tune the degree of ionization in sputtering processes. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Determination of the Energy Flux of a Commercial Atmospheric‐Pressure Plasma Jet for Different Process Gases and Distances Between Nozzle Outlet and Substrate Surface

AbstractThe energy flux of an atmospheric‐pressure plasma jet for surface treatment has been investigated by a calorimetric probe. Generally, the investigations exhibit that the main contributions of the total energy influx from the plasma to the substrate surface originate from the neutrals regarding high gas temperature coupled with a high gas flow. The use of nitrogen as process gas shows a higher energy flux compared to oxygen and air presumably caused by increased gas temperature as well as by higher molecule formation and recombination energy of N2. Moreover, the lateral expansion of the plasma beam could be roughly determined by a spatially resolved analysis of the energy influx. A top part mounted on the nozzle, commonly used for the injection of additional precursor gases, showed a significant effect on the flow behavior and collision entailed relaxation of the excited plasma species leading to a restraining of the plasma jet. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Storm-time characteristics of intense geomagnetic storms ( [formula omitted]) at low-latitudes and associatedenergetics

Tremendous amount of solar energy is hurled into the space by transient sporadic emissions occurring within the Sun. A fraction of this energy is transferred into the Earth's magnetosphere by the magnetic reconnection process. Interplanetary magnetic field plays a crucial role in the excitation of geomagnetic storms and their subsequent evolution. The present study attempts to determine the influence of post-shock duration of southward B z on the development and intensification of intense ( Dst ≤ − 200 nT ) geomagnetic storms. The study presents 18 big storm events that occurred during the solar cycle 23. In all the cases under study, the interplanetary shocks were driven by the interplanetary coronal mass ejections (ICMEs). The ICME structures may contain southward magnetic fields within the sheath, the magnetic cloud or both in succession, which can lead to the development of intense geomagnetic storms. In addition, dependence of storm strength on the total energy influx into the magnetosphere ( ϵ ) and ring current ( E RC ) energy is also assessed. Geomagnetic storm characteristics are examined at a low-latitude station, Alibag (geographic lat. 18 . 63 ∘ N , long. 72 . 87 ∘ E ; geomagnetic lat. 10 . 02 ∘ N , long. 145 . 97 ∘ ), using high resolution digital data. The minimum duration of southward B z for strengthening the storms is ∼ 1.25 h . All intense storms are found to have minimum values of southward directed B z to be ≤ − 18 nT and interplanetary electric field E y > 12 mV / m . Intensity of geomagnetic storms at low-latitudes follows a fairly linear dependence on the ring current energy.

Spatially resolved thermal probe measurement for the investigation of the energy influx in an rf-plasma

The total energy influx for a typical radiofrequency process plasma has been measured by means of a simple thermal probe. The procedure is based on the measurement of temporal slope of the substrate temperature during the plasma process. A substrate dummy which is thermally isolated and inserted into the plasma at substrate position served as thermal probe. It can be moved in vertical and horizontal directions in order to measure the different energy influxes and their topology in the reactor vessel. The knowledge of the spatial distribution is important for coating or sputtering processes.Different contributions to the total energy influx can be identified by different orientation of the thermal probe. If the thermal probe is orientated to the rf-electrode (“down”) the energy influx is much higher than in the opposite direction. This difference can be explained by an additional influx due to the secondary electron emission from the powered rf-electrode.

Modulation of Food Intake by Glucose in Patients With Type 2 Diabetes

A gain in body weight is a common adverse effect of glucose-lowering therapies in patients with type 2 diabetes, the mechanisms of which are not completely understood. Blood glucose is considered to play a crucial role in the regulation of food intake. On this background, we hypothesized that a short-term reduction of blood glucose concentration to normal values acutely increases food intake in type 2 diabetic patients. To test this hypothesis, 12 patients with type 2 diabetes were examined twice, once during a euglycemic (5.0 mmol/l) clamp experiment and another time during a hyperglycemic (10.5 mmol/l) clamp. The experiments were performed in a single-blind fashion with the order of conditions balanced across patients. On both clamp conditions, insulin was infused at a constant rate of 2.5 mU/kg per min for 125 min. Simultaneously, a glucose solution was infused at a variable rate to achieve target glycemic levels. During the final 30 min of the clamps, the patients were allowed to eat as much as they liked from a standard breakfast buffet. Compared with the hyperglycemic condition, the patients ingested on average 25 +/- 10% more energy during euglycemia (645 +/- 75 vs. 483 +/- 37 kcal; P = 0.029). The increased energy intake during euglycemia was equally distributed across macronutrient components, i.e., during euglycemia the patients ate more carbohydrates (+27.1 +/- 11.4%; P = 0.037), fat (+22.5 +/- 10.0%; P = 0.046), and proteins (+25.2 +/- 11.2%; P = 0.046) than during hyperglycemia. Circulating levels of insulin, amylin, leptin, ghrelin, and glucagon-like peptide-1 did not differ between the euglycemic and hyperglycemia clamp, excluding a major contribution of these hormones to the difference in food intake. Summing up the glucose administered intravenously and the food ingested yielded a remarkably similar total energy influx in both conditions (794 +/- 64 vs. 790 +/- 53 kcal; P = 0.961). Together our data suggest that total energy supply to the organism is tightly regulated on a short-term basis independent of the route of influx. Alternatively, it can be hypothesized that euglycemia stimulated or that hyperglycemia suppressed food intake at the subsequent buffet meal in our type 2 diabetic patients. Regardless of these different interpretations, our data indicate an important regulatory role of glucose for food intake in type 2 diabetic patients that is of considerable clinical relevance.

Influence of basin scale on structure of natural aquatic communities

The aim of the study was to analyze the influence of aquatic ecosystem size on community structure. Analysis is based on quantitative indices, describing integral communities and comparison of their biomass size spectra with standard patterns. Comparative analysis of widely differing aquatic communities shows that certain characteristics of the community structure withstand considerable changes of many important parameters of the abiotic environment and taxonomic composition of the community. At the same time, there are some changes in fine structure of the community size spectra, which can now be documented and measured with relatively high precision due to development of modern automated means of data acquisition. In this study, application of spectral descriptions is discussed as applied to communities of River Jordan-Lake Kinneret aquatic system. It follows from the theoretical scheme developed that, for analysis, the most important part of the community size spectrum is its right extreme, i.e. body size of the largest species of the ecosystem. In the case of Lake Kinneret, that is fish. The fish biomass size spectra were obtained using dual-beam hydro-acoustics techniques. The parameter comparison shows that for riverine systems (i.e. ecological systems with a high role of allochtonous organic matter in the total energy influx of the community), both the water area and the watershed basin (including its terrestrial part) deserve attention as the appropriate scaling parameter.

On the energy balance of substrate surfaces during plasma cleaning of lubricants

During dc oxygen plasma cleaning of hydocarbon-containing light lubricants deposited on aluminum the energy fluxes towards the substrates have been determined by temperature measurements. The contributions to the total energy influx are due to exothermic combustion reactions of the petroleum-like lubricants by the plasma generated oxygen atoms and due to kinetic ion energy transfer. By variation of the discharge mode and substrate voltage the effect of the two contributions could be separated. In the anomalous glow discharge mode, where the ion energy influx was of importance, the treated substrates were at cathode potential (− 500 to − 1200 V) and vice versa, in the hollow cathode discharge mode the substrates were at floating potential where only the chemical component contributes to substrate heating. A comparison of the measurements with calculations based on simple model assumptions is given.

Energetic He+ precipitation in a mid‐latitude aurora

Optical spectra of a mid‐latitude aurora on September 21–22 indicated that the observed emissions were caused by energetic ions (O+ or He+). In an earlier paper it was shown that the spectral features could be fairly well explained by a flux of precipitating energetic O+ with characteristics similar to O+ fluxes that have been observed in large magnetic storms. A comprehensive model is used to trace the energy degradation of the incoming O+ ions, the production of energetic neutrals, and the subsequent scattering of these neutrals in altitude and energy. In this study we have computed the atmospheric impact (in terms of heating, ionization, and excitation of certain emissions) if the incoming flux is He+ instead of O+. The results show that an energetic He+ flux is very efficient in producing both ionization and a backscattered flux out of the atmosphere. Of the total energy influx, approximately 50% goes into ionization (compared with ∼2% in the case of O+) and 40% is backscattered to the magnetosphere or escapes (compared with 16% for O+). By contrast the He+ flux is less efficient at heating the atmosphere (10% compared with 82%). The He+ flux is very efficient in producing N2+ 1 N (first negative) emission, but essentially does not excite the N2 2 P (second positive) system. From these results it is concluded that the aurora observed on September 22, 1982, is well explained by an influx of energetic O+ together with a 6% admixture of He+.

Energy, Nitrogen, and Electrolyte Flux and Sea Water Drinking in the Sea Otter Enhydra Lutris

An elevated metabolism requires the sea otter, Enhydra lutris, to include large quantities of invertebrate prey in its diet. This necessitates processing large quantities of energy, nitrogen, electrolytes, and water. Feeding studies were conducted to document these high material and energy fluxes and the dilution of tritiated water through time was used to measure total water flux. Total energy influx on a diet of clam and squid was 234 ± 19 (X ± SE) kcal/kg-day with an assimilation efficiency of 82% and an estimated metabolic efficiency of 72%. Material influx from food was 5.22 ± 0.41 (X ± SE) g/kg-day nitrogen and 166 meq/kg-day electrolytes (Cl, Na, K, Mg). The presence of large lobulate kidneys may allow for the production of large volumes of urine at elevated concentrations. Urine samples from wild and captive animals had a mean osmotic pressure of 1,627 ± 91 mOsm/kg (range, 910-2,130), which was composed of 647 meq/L Na, K, Cl and 698 ± 67 mmol/L urea. Total water flux was 269 ± 25 mL/kg-day. Mean ...

Auroral x-rays, cosmic rays, and related phenomena during the storm of February 10-11, 1958

Balloon observations were made during the auroral storm of February 10- 11, 1958, at Minneapolis. Strong x-ray bursts in two groups were detected. The groups appeared coincident with two large magnetic bays, with strong radio noise absorption, and with the passage across the zenith of a very large amount of auroral luminosity. From the x-ray intensity and measured energies, an electron current of 0.6 x 10/sup 6/ electrons /cm/sup 2// scc was present. These electrons ionizing the upper D layer accounted for the increased cosmic noise absorption. The x-rays themselves carried 1000 times less energy than the electrons and could not provide sufficient ionization for the observed radio absorption. Visual auroral fornis during this storm are reported to have lower borders at thc 200 to 300 km level. There is thus a difficulty in bringing the electrons to the D layer without ani accompanying visible aurora. A cosmic-ray decrease accompanied the storm and was observed to be from 4 to 6% at sea level, 21% in the balloon altitude ionization, and 15% in total energy influx at 55 deg geomagnetic latitude. Compared with the great intensity of the magnetic and auroral phenomena in this storm, the cosmic-ray modulation was notmore » exceptionally large. (auth)« less