scholarly journals Assessing Geological Resource and Risk Associated Radiation While Refining Opal Minerals Using Local Mechanism

2021 ◽  
Vol 9 (3) ◽  
pp. 53
Author(s):  
Baye Zinabe Kebede
Keyword(s):  
Local Mechanism

scholarly journals Out-of-plane local mechanism analysis with finite element method

2021 ◽  
Vol 8 (1) ◽  
pp. 130-136
Author(s):  
Roberto Spagnuolo
Keyword(s):  
Finite Element ◽  
Masonry Walls ◽  
Finite Element Models ◽  
Mechanism Analysis ◽  
Fem Method ◽  
Local Mechanism ◽  
Out Of Plane ◽  
Smeared Crack ◽  
The Stability ◽  
No Tension Material

Abstract The stability check of masonry structures is a debated problem in Italy that poses serious problems for its extensive use. Indeed, the danger of out of plane collapse of masonry walls, which is one of the more challenging to evaluate, is traditionally addressed not using finite element models (FEM). The power of FEM is not properly used and some simplified method are preferred. In this paper the use of the thrust surface is suggested. This concept allows to to evaluate the eccentricity of the membrane stresses using the FEM method. For this purpose a sophisticated, layered, finite element with a no-tension material is used. To model a no-tension material we used the smeared crack method as it is not mesh-dependent and it is well known since the early ’80 in an ASCE Report [1]. The described element has been implemented by the author in the program Nòlian by Softing.

scholarly journals Ontology of a Wavefunction from the Perspective of an Invariant Proper Time

2021 ◽  
Author(s):  
Salim Yasmineh
Keyword(s):  
Quantum Mechanics ◽  
Special Relativity ◽  
Proper Time ◽  
Finite Density ◽  
Confining Potential ◽  
Standard Time ◽  
Related Matter ◽  
Local Mechanism ◽  
Non Local ◽  
The Individual

All the arguments of a wavefunction are defined at the same instant implying a notion of simultaneity. In a somewhat related matter, certain phenomena in quantum mechanics seem to have non-local causal relations. Both concepts are in contradiction with special relativity. We propose to define the wavefunction with respect to the invariant proper time of special relativity instead of standard time. Moreover, we shall adopt the original idea of Schrodinger suggesting that the wavefunction represents an ontological cloud-like object that we shall call ‘individual fabric’ that has a finite density amplitude vanishing at infinity. Consequently, measurement can be assimilated to a confining potential that triggers an inherent non-local mechanism within the individual fabric. It is formalised by multiplying the wavefunction with a localising gaussian as in the GRW theory but in a deterministic manner.

Local Mechanism of Phenyl Ring π-Flips in Glassy Polycarbonate

1997 ◽  
Vol 30 (6) ◽  
pp. 1741-1751 ◽  
Author(s):  
Duane R. Whitney ◽  
Robert Yaris
Keyword(s):  
Phenyl Ring ◽  
Local Mechanism

scholarly journals Local mechanism of CO2 action of cat pial arterioles.

Stroke ◽  
1977 ◽  
Vol 8 (2) ◽  
pp. 226-229 ◽  
Author(s):  
H A Kontos ◽  
E P Wei ◽  
A J Raper ◽  
J L Patterson
Keyword(s):  
Local Mechanism ◽  
Pial Arterioles

scholarly journals Pyramid Constrained Self-Attention Network for Fast Video Salient Object Detection

2020 ◽  
Vol 34 (07) ◽  
pp. 10869-10876 ◽  
Author(s):  
Yuchao Gu ◽  
Lijuan Wang ◽  
Ziqin Wang ◽  
Yun Liu ◽  
Ming-Ming Cheng ◽  
...  
Keyword(s):  
Object Detection ◽  
Short Term Memory ◽  
Salient Object Detection ◽  
Object Motion ◽  
Salient Object ◽  
Motion Cues ◽  
Spatiotemporal Information ◽  
Local Mechanism ◽  
Non Local ◽  
Pyramid Structures

Spatiotemporal information is essential for video salient object detection (VSOD) due to the highly attractive object motion for human's attention. Previous VSOD methods usually use Long Short-Term Memory (LSTM) or 3D ConvNet (C3D), which can only encode motion information through step-by-step propagation in the temporal domain. Recently, the non-local mechanism is proposed to capture long-range dependencies directly. However, it is not straightforward to apply the non-local mechanism into VSOD, because i) it fails to capture motion cues and tends to learn motion-independent global contexts; ii) its computation and memory costs are prohibitive for video dense prediction tasks such as VSOD. To address the above problems, we design a Constrained Self-Attention (CSA) operation to capture motion cues, based on the prior that objects always move in a continuous trajectory. We group a set of CSA operations in Pyramid structures (PCSA) to capture objects at various scales and speeds. Extensive experimental results demonstrate that our method outperforms previous state-of-the-art methods in both accuracy and speed (110 FPS on a single Titan Xp) on five challenge datasets. Our code is available at https://github.com/guyuchao/PyramidCSA.

scholarly journals Methods to describe barotropic vortices by global fields and vortex characteristics

2002 ◽  
Vol 9 (3/4) ◽  
pp. 189-200 ◽  
Author(s):  
W.-G. Früh
Keyword(s):  
Large Scale ◽  
Solid Boundary ◽  
Eof Analysis ◽  
Vortex Identification ◽  
Global Mode ◽  
Local Structures ◽  
Local Mechanism ◽  
Mode 2 ◽  
Identification Technique ◽  
Analyse Time

Abstract. Results from an experimental study of vortices in a rotating shear layer are presented. The data are in the form of maps of the instantaneous horizontal velocity field obtained by a particle tracking technique. Two fundamentally different methods to analyse time series of these velocity fields are presented and compared. One technique is the empirical orthogonal function (EOF) analysis, and the other method describes the flow field in terms of a few individual localised vortices. The flows discussed here are time-dependent two-vortex flows, which could either be described as a global mode 2 or as a collection of four unequal vortices. The results show that, while EOF analysis is a very powerful tool to detect fairly regular travelling modes or stationary features, it cannot detect local dynamics. The vortex identification technique is very good at detecting local structures and events but cannot put them into the context of a global flow structure. The comparison of the techniques shows indications that the time-dependence found in the system for low mode numbers could arise from an interaction of the large scale, global-mode flow with a local mechanism of vortex generation and shedding at a solid boundary.

Heart failure depresses endothelium-dependent responses in canine femoral artery

1989 ◽  
Vol 256 (4) ◽  
pp. H962-H967 ◽  
Author(s):  
L. Kaiser ◽  
R. C. Spickard ◽  
N. B. Olivier
Keyword(s):  
Heart Failure ◽  
Femoral Artery ◽  
Peripheral Resistance ◽  
Vascular Control ◽  
Experimental Heart Failure ◽  
Low Concentrations ◽  
Local Mechanism ◽  
Before And After ◽  
Significant Depression ◽  
Response To Exercise

Vascular responses to many physiological stresses are abnormal in heart failure. Increased peripheral resistance and a reduction in the vasodilator response to exercise and ischemia are examples of this abnormal vascular control. Such abnormal vascular control in heart failure is a result of interplay between neural, hormonal, and local vascular factors. This study was designed to test the hypothesis that a specific local mechanism, endothelium-dependent relaxation to acetylcholine (ACh), is depressed in experimental heart failure. Experiments were performed on 11 purebred beagles. Experimental heart failure was induced by rapid ventricular pacing for approximately 30 days. Femoral artery diameter was measured by sonomicrometry, and dose-response relationships to ACh, norepinephrine (NE), and nitroglycerin (NTG) were done before and after inhibition of cyclooxygenase by indomethacin. Heart failure resulted in a significant depression of ACh relaxation at all concentrations. In dogs with heart failure, indomethacin enhanced the dilation response to low concentrations of ACh. Constriction to NE and dilation to NTG were unchanged by heart failure. These data demonstrate that in the canine femoral artery endothelium-dependent dilation to ACh is depressed in experimental heart failure. Depression of endothelium-dependent vasodilation represents one local mechanism for abnormal control of the vasculature in congestive heart failure.

Effect of a brief contraction of forearm muscles on forearm blood flow

1964 ◽  
Vol 19 (1) ◽  
pp. 142-146 ◽  
Author(s):  
Adrian Corcondilas ◽  
Gabriel T. Koroxenidis ◽  
John T. Shepherd
Keyword(s):  
Blood Flow ◽  
Forearm Blood Flow ◽  
Venous Blood ◽  
Additional Increase ◽  
Maximal Increase ◽  
Forearm Muscles ◽  
Local Mechanism ◽  
Rhythmic Contractions ◽  
Exercise Induced ◽  
Local Nature

With the use of a strain-gauge plethysmograph, the effect of a brief (0.3 sec) contraction of the forearm muscles on forearm blood flow has been studied in eight healthy adults. An increase in flow due to dilatation of the muscle vessels could be detected within a second after the completion of the contraction. This increase was proportional to the strength of the contraction. The blood flow was maximal immediately and decreased rapidly. A second contraction of the same magnitude made during the period of increased flow caused an additional increase in flow. The maximal increase in flow caused by a strong brief contraction was only about 25% of that recorded after strong repeated rhythmic contractions or a sustained contraction. Cervical sympathectomy did not change these findings, indicating the local nature of the response. Since breathing oxygen failed to reduce the dilatation for a given strength of contraction, it is unlikely that oxygen lack was the stimulus for vasodilatation. The oxygen saturation of blood that drained the muscles could not be determined accurately immediately after contraction because at this time, muscle venous blood was contaminated by venous blood from the skin. exercise-induced vasodilatation; local mechanism of vasodilatation; venous O2 saturation during muscle contraction; brachial arterial pressure during vasodilatation; speed of muscle vasodilatation Submitted on May 8, 1963

scholarly journals Circulating Prouroguanylin Is Processed to Its Active Natriuretic Form Exclusively within the Renal Tubules

Endocrinology ◽  
2008 ◽  
Vol 149 (9) ◽  
pp. 4499-4509 ◽  
Author(s):  
Xun Qian ◽  
Nicholas G. Moss ◽  
Robert C. Fellner ◽  
Michael F. Goy
Keyword(s):  
Salt Intake ◽  
Specific Activity ◽  
Active Form ◽  
High Specific Activity ◽  
Kinetic Studies ◽  
Target Organ ◽  
Renal Tubules ◽  
Local Mechanism ◽  
Signaling Axis ◽  
Endocrine Agent

The intestine and kidney are linked by a mechanism that increases salt excretion in response to salt intake. The peptide uroguanylin (UGn) is thought to mediate this signaling axis. Therefore, it was surprising to find (as reported in a companion publication) that UGn is stored in the intestine and circulates in the plasma almost exclusively in the form of its biologically inactive propeptide precursor, prouroguanylin (proUGn), and, furthermore, that infused proUGn leads to natriuretic activity. Here, we investigate the fate of circulating proUGn. Kinetic studies show rapid renal clearance of radiolabeled propeptide. Radiolabel accumulates at high specific activity in kidney (relative to other organs) and urine (relative to plasma). The principal metabolites found in kidney homogenates are free cysteine and methionine. In contrast, urine contains cysteine, methionine, and three other radioactive peaks, one comigrating with authentic rat UGn15. Interestingly, proUGn is not converted to these or other metabolites in plasma, indicating that circulating proUGn is not processed before entering the kidney. Therefore, our findings suggest that proUGn is the true endocrine agent released in response to salt intake and that the response of the kidney is dependent on conversion of the propeptide to an active form after it reaches the renal tubules. Furthermore, proUGn metabolites (other than small amounts of cysteine and methionine) are not returned to the circulation from the kidney or any other organ. Thus, to respond to proUGn released from the gut, any target organ must use a local mechanism for production of active peptide.

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