An upper limit for the total energy of relativistic particles contained in the early stages of supernova explosions

1979 ◽  
Vol 230 ◽  
pp. 713 ◽  
Author(s):  
J. H. Beall
Keyword(s):  
Total Energy ◽  
Early Stages ◽  
Upper Limit ◽  
Supernova Explosions ◽  
Relativistic Particles

scholarly journals Collapse of the Neutron Star Induced by Phase Transitions and Neutrino Emission from SN1987A

1988 ◽  
Vol 108 ◽  
pp. 430-431
Author(s):  
Mariko Takahara ◽  
Katsuhiko Sato
Keyword(s):  
Phase Transitions ◽  
Neutron Star ◽  
Total Energy ◽  
Neutrino Emission ◽  
Standard Scenario ◽  
Supernova Explosions

The neutrino burst from SN1987A were detected by KAMIOKANDE and also IMB in February this year. The neutrino events detected by KAMIOKANDE were clustered into three bunches; event number 1-5, 7-9, 10-12. The first two bunches of the neutrino events can be understood by the standard scenario of supernova explosions.However, it is very difficult to explain the last bunch of the neutrino events by the standard scenario, especially the total energy of the neutrinos and the radius of the neutrino sphere; it is necessary at least several times of 1052 ergs to explain the total energy of the last three events. In order to explain this energy, we must consider the non-standard mechanism of the neutrino emission.

scholarly journals The nutrition transition in Barbados: trends in macronutrient supply from 1961 to 2003

2010 ◽  
Vol 104 (8) ◽  
pp. 1222-1229 ◽  
Author(s):  
T. Sheehy ◽  
S. Sharma
Keyword(s):  
Total Energy ◽  
Nutrition Transition ◽  
Premature Death ◽  
Limit Set ◽  
Dietary Energy ◽  
Analysis Software ◽  
Dietary Analysis ◽  
Balance Sheets ◽  
Upper Limit ◽  
Per Capita

Barbados has been experiencing increasing rates of obesity and chronic non-communicable diseases characteristic of a country in nutrition transition. However, few studies have been carried out on how precisely the diet has changed in recent decades. Our aim was to analyse the FAO food balance sheets for Barbados from 1961 to 2003 in order to characterise the changes that have taken place in the macronutrient supply of the country during that period. Annual food balance sheets were downloaded from the FAOSTAT database, and per capita supply for twelve commodity groupings was analysed for energy and macronutrient levels using WISP dietary analysis software (Tinuviel Software, Llanfechell, Anglesey, UK). The food supply in 2003 provided over 2500 kJ (about 600 kcal) more energy per capita per d than it did in 1961. Energy from carbohydrate as a percentage of total energy has fallen from 70 % in 1961 to 57 % in 2003 and is now at the lower end of WHO recommendations. Energy from fat as a percentage of total energy increased from 19 % to 28 % and now lies at the upper end of WHO recommendations. Sugars, at over 17 % of dietary energy, are well above the upper limit set by the WHO. Despite having methodological limitations associated with the use of food balance statistics, our data suggest that these imbalances need to be addressed as a matter of priority in order to try to reverse the incidence of nutrition-related chronic diseases that are projected to cause increasing disability and premature death in the country in the coming years.

scholarly journals The energy of disintegration of radio-phosphorous [P 30 ]

1935 ◽  
Vol 152 (877) ◽  
pp. 714-723 ◽  
Keyword(s):  
Excited State ◽  
Total Energy ◽  
Continuous Spectrum ◽  
Atomic Number ◽  
Particle Bombardment ◽  
Ground State ◽  
Radioactive Elements ◽  
Upper Limit ◽  
Association Meeting ◽  
The Difference

The exact masses of the nuclei are quantity of great interest depending directly on the forces of cohesion between the nuclear particles. Already much valuable information has been obtained about the lighter element both by mass-spectrographic methods and by the study of atomic dis-integrations. The discovery of the new radioactive elements has extended greatly the number of nuclei open to investigation, but since nearly all of these disintegrate by emitting either positrons or electrons forming a continuous spectrum we meet here the same difficulty in determining the total energy change in the disintegration as with the natural β-ray bodies. In this latter case Henderson* has proved the correcting of the suggestion of Ellis and Mott that the difference of energy of two nuclei, apart from γ-emission, is given by the upper limit of the β-ray spectrum. However, as was emphasized by Cockroft at the British Association Meeting at Norwich, in September, 1935, this is a point which needs verification in the region of low atomic number and particularly for positron disintegration. We have attempted to obtain some information on this point by investigating the disintegration of radio-phosphorus [P30] formed from aluminium by α-particle bombardment, The disintegration of radio phosphorus has already been investigated several times, but there is such a notable disagreement between the values given by different observers for the energy of the upper limit that we felt fresh experiments were needed, further, it is necessary to determine whether the upper limit corresponds to the formation of the ground state or of an excited state of the product nucleus.

Cilostazol attenuates ventricular arrhythmia induction and improves defibrillation efficacy in swine

2010 ◽  
Vol 88 (4) ◽  
pp. 422-428 ◽  
Author(s):  
Natnicha Kanlop ◽  
Krekwit Shinlapawittayatorn ◽  
Rattapong Sungnoon ◽  
Punate Weerateerangkul ◽  
Siriporn Chattipakorn ◽  
...  
Keyword(s):  
Total Energy ◽  
Pacing Threshold ◽  
Peak Voltage ◽  
Cellular Electrophysiology ◽  
Phosphodiesterase 3 ◽  
Upper Limit ◽  
Upper Limit Of Vulnerability ◽  
Before And After ◽  
Lower Total Energy ◽  
Experimental Group

Previous reports demonstrated that cilostazol, a phosphodiesterase 3 inhibitor, affected cellular electrophysiology and reduced episodes of ventricular fibrillation (VF) in patients with Brugada syndrome. However, its effects on VF induction and defibrillation efficacy have never been investigated. We tested the hypothesis that cilostazol increases the VF threshold (VFT) and decreases the upper limit of vulnerability (ULV) and the defibrillation threshold (DFT). A total of 48 pigs were randomly assigned to defibrillation and VF induction studies. The diastolic pacing threshold (DPT), VFT, ULV, DFT, and effective refractory period were determined before and after the infusion of cilostazol at 6 mg/kg, 3 mg/kg, or vehicle. The DPT was significantly increased after administration of 3 and 6 mg/kg cilostazol. The ULV and DFT were significantly decreased after administration of 6 mg/kg cilostazol only. The ULV in the 6 mg/kg group had 12% lower peak voltage and 25% lower total energy, and the DFT had 13% lower peak voltage and 25% lower total energy. The VFT was not altered in any experimental group. This study shows that cilostazol administration significantly increased the DPT, which was associated with significantly reduced DFT and ULV.

scholarly journals Maximum age for a concretion at Green Creek, Ontario

2011 ◽  
Vol 34 (2) ◽  
pp. 229-238 ◽  
Author(s):  
Nelson R. Gadd
Keyword(s):  
Skeletal Remains ◽  
Early Stages ◽  
Fossil Remains ◽  
Upper Limit ◽  
Chemically Induced ◽  
Carbonate Concretion ◽  
Carbonate Cementation ◽  
Apparent Age

Wood (? Salix sp.) from a concretionary nodule found at - 43 m a.s.l. at the Green Creek, Ontario, site was dated at 9 960 ± 820 BP (GSC-2498). The carbonate concretion has an apparent age of 14 400 ± 250 BP (GSC-2530). The wood date is a maximum age for the enclosing sediment and for its cementation; the carbonate date appears anomalous. At the time of the upper limit of error for the wood date (10 780 BP) Champlain Sea stood at or above 100 m a.s.l. The true age of the wood probably is compatible with that of freswhater shells at - 53 m a.s.l. at Bourget, Ontario (10 200 ± 90; GSC-1968), and of wood at - 61 m a.s.l. at Hawkesbury, Ontario (9 860 ± 330; BGS-257). Terrace sediments at ~ 43 m a.s.l. probably are of freshwater origin. Terrestrial and freshwater flora and fauna in earlier collections of concretions from Green Creek also suggest an estuarine to freswhater environment for the enclosing sediments. Occurrence of complete skeletons of fish and other vertebrates in concretions is related to chemically induced carbonate cementation during early stages of putrefaction of soft-bodied animals. This could preserve skeletal remains through several cycles of erosion. Therefore some concretions carry fossil remains that may be allochtonous to the sediment in which they now occur.

scholarly journals Large scale direct galaxy collision simulations with central supermassive binary black holes

2014 ◽  
Vol 10 (S312) ◽  
pp. 105-108
Author(s):  
Margaryta Sobolenko ◽  
Peter Berczik ◽  
Rainer Spurzem
Keyword(s):  
Large Scale ◽  
High Mass ◽  
Astrophysical Object ◽  
Binary Black Holes ◽  
Supermassive Black Hole ◽  
Upper Limit ◽  
The Galaxy ◽  
Black Hole Binary ◽  
Correction Terms ◽  
Relativistic Particles

AbstractWe present a set of, large scale direct N-body simulations of the galaxy collision with the central Supermassive Black Hole Binary (SMBHB) system. Based on our simulations which include the accurate Post Newtonian (PN) relativistic dynamical corrections we can estimated the merging time for the real astrophysical object. Each galaxy initially was represented as a set of particles (up to N=500k) with Plummer distribution. The SMBHBs system is described using the two special high mass, i.e. “relativistic”, particles. The interaction between these two particles have an extra PN correction terms (up to 3.5PN). Merging time upper limit was obtained for the closely interacting galaxy system NGC 6240.

Supernovae and interstellar gas dynamics

1967 ◽  
Vol 31 ◽  
pp. 117-119
Author(s):  
F. D. Kahn ◽  
L. Woltjer
Keyword(s):  
Lower Limit ◽  
High Velocity ◽  
Gas Dynamics ◽  
Interstellar Cloud ◽  
Interstellar Gas ◽  
Random Motions ◽  
Relativistic Particles

The efficiency of the transfer of energy from supernovae into interstellar cloud motions is investigated. A lower limit of about 0·002 is obtained, but values near 0·01 are more likely. Taking all uncertainties in the theory and observations into account, the energy per supernova, in the form of relativistic particles or high-velocity matter, needed to maintain the random motions in the interstellar gas is estimated as 1051·4±1ergs.

Spherulitic crystal growth in the prodissoconch larval of Crassostrea virginica

1983 ◽  
Vol 41 ◽  
pp. 518-519
Author(s):  
George G. Cocks ◽  
Louis Leibovitz ◽  
DoSuk D. Lee
Keyword(s):  
Crystal Structure ◽  
Crassostrea Virginica ◽  
Crystal Orientation ◽  
Developmental Changes ◽  
Gastrula Stage ◽  
Orthorhombic Crystal ◽  
Orthorhombic Crystal Structure ◽  
Stages Of Growth ◽  
Early Stages ◽  
Initial Deposition

Our understanding of the structure and the formation of inorganic minerals in the bivalve shells has been considerably advanced by the use of electron microscope. However, very little is known about the ultrastructure of valves in the larval stage of the oysters. The present study examines the developmental changes which occur between the time of conception to the early stages of Dissoconch in the Crassostrea virginica(Gmelin), focusing on the initial deposition of inorganic crystals by the oysters.The spawning was induced by elevating the temperature of the seawater where the adult oysters were conditioned. The eggs and sperm were collected separately, then immediately mixed for the fertilizations to occur. Fertilized animals were kept in the incubator where various stages of development were stopped and observed. The detailed analysis of the early stages of growth showed that CaCO3 crystals(aragonite), with orthorhombic crystal structure, are deposited as early as gastrula stage(Figuresla-b). The next stage in development, the prodissoconch, revealed that the crystal orientation is in the form of spherulites.

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

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