scholarly journals Three-Dimensional Failure Patterns Around an Inflating Magmatic Chamber

2018 ◽  
Vol 19 (3) ◽  
pp. 749-771 ◽  
Author(s):  
Muriel Gerbault ◽  
Riad Hassani ◽  
Camila Novoa Lizama ◽  
Alban Souche
Keyword(s):  
Three Dimensional ◽  
Magmatic Chamber ◽  
Failure Patterns

Survival and Failure Patterns of High-Grade Gliomas After Three-Dimensional Conformal Radiotherapy

2002 ◽  
Vol 20 (6) ◽  
pp. 1635-1642 ◽  
Author(s):  
June L. Chan ◽  
Susan W. Lee ◽  
Benedick A. Fraass ◽  
Daniel P. Normolle ◽  
Harry S. Greenberg ◽  
...  
Keyword(s):  
Dose Escalation ◽  
Three Dimensional ◽  
Conformal Radiotherapy ◽  
High Dose ◽  
Normal Brain ◽  
High Grade ◽  
Significant Treatment ◽  
Failure Patterns ◽  
High Grade Gliomas ◽  
Three Dimensional Conformal Radiotherapy

PURPOSE: The goal of three-dimensional (3-D) conformal radiation is to increase the dose delivered to tumor while minimizing dose to surrounding normal brain. Previously it has been shown that even escalated doses of 70 to 80 Gy have failure patterns that are predominantly local. This article describes the failure patterns and survival seen with high-grade gliomas given 90 Gy using a 3-D conformal intensity-modulated radiation technique. PATIENTS AND METHODS: From April 1996 to April 1999, 34 patients with supratentorial high-grade gliomas were treated to 90 Gy. For those that recurred, failure patterns were defined in terms of percentage of recurrent tumor located within the high-dose region. Recurrences with more than 95% of their volume within the high-dose region were considered central; those with 80% to 95%, 20% to 80%, and less than 20% were considered in-field, marginal, and distant, respectively. RESULTS: The median age was 55 years, and median follow-up was 11.7 months. At time of analysis, 23 (67.6%) of 34 patients had developed radiographic evidence of recurrence. The patterns of failure were 18 (78%) of 23 central, three (13%) of 23 in-field, two (9%) of 23 marginal, and zero (0%) of 23 distant. The median survival was 11.7 months, with 1-year survival of 47.1% and 2-year survival of 12.9%. No significant treatment toxicities were observed. CONCLUSION: Despite dose escalation to 90 Gy, the predominant failure pattern in high-grade gliomas remains local. This suggests that close margins used in highly conformal treatments do not increase the risk of marginal or distant recurrences. Our results indicate that intensification of local radiotherapy with dose escalation is feasible and deserves further evaluation for high-grade gliomas.

scholarly journals 3D Limit Analysis of the Transient Stability of Slope during Pile Driving in Nonhomogeneous and Anisotropic Soil

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Pingping Rao ◽  
Jian Wu ◽  
Zhihao Mo
Keyword(s):  
Upper Bound ◽  
Limit Analysis ◽  
Transient Stability ◽  
Three Dimensional ◽  
Optimization Method ◽  
Pile Driving ◽  
Failure Patterns ◽  
Anisotropic Soil ◽  
The Stability ◽  
Rotational Failure

To evaluate the stability of a slope subjected to pile driving in nonhomogeneous and anisotropic soils, an upper-bound limit analysis method is employed in this paper. A 3D rotational failure mechanism for soil slope is extended to account for different failure patterns (i.e., toe failure and base failure). In order to avoid missing the global minimum, an efficient optimization method is simultaneously employed to find the least upper bound to the factor of safety (FS). The effectiveness and accuracy of the proposed method is well demonstrated by comparing the results obtained from the proposed approach with the solutions from published literatures. The effects of key designing parameters are presented and discussed. The optimal pile location and the three-dimensional effect of the slope are discussed. In addition, these results highlight that the adverse effects of pile driving on slope stability should be highly concerned during the design of geotechnical infrastructures, rather than emphasizing the reinforcement effect of a pile only.

scholarly journals Numerical Investigation on the Evolution of Mechanical Properties of Rock Affected by Micro-Parameters

2020 ◽  
Vol 10 (14) ◽  
pp. 4957
Author(s):  
Haoyu Rong ◽  
Guichen Li ◽  
Dongxu Liang ◽  
Changlun Sun ◽  
Suhui Zhang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Uniaxial Compressive Strength ◽  
Stress Ratio ◽  
Three Dimensional ◽  
Particle Flow Code ◽  
Parameter Calibration ◽  
Failure Characteristics ◽  
Failure Patterns ◽  
Response Characteristics ◽  
Bond Model

Investigating the micro-parameters of rock is vital for understanding the macro-properties of rock, such as the uniaxial compressive strength (UCS), Young’s modulus, failure patterns, etc. In this paper, based on the experimental results of rock material, a parallel-bond model in three-dimensional particle flow code (PFC3D) was applied to investigate the effects of the joint action of bond stiffness ratio and bond stress ratio on macro-properties of rock. The uniaxial compressive strength, stress–strain relationships, and failure characteristics, as well as underlying compression and failure mechanisms, in the process of parameter calibration, were systematically studied. The results indicated that the interaction of several micro-parameters would obviously change the response characteristics of the macro-properties of the model. The mechanism of the effects of various micro-parameters on the macro-properties of the model was further revealed. The change of the micro-parameters would change the strength and stress state of the bond between particles. The research results could promote the understanding of the failure mechanism of rock and improve the efficiency of micro-parameter calibration and the accuracy of calibration results.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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