FEA Study of Belt Angle Effect to Cornering Stiffness and Ply Steer

2009 ◽  
Author(s):  
Min Lu
Keyword(s):  
Numerical Procedure ◽  
Lane Change ◽  
Tire Model ◽  
Angle Variation ◽  
Factors Affecting ◽  
Region I ◽  
Angle Effect ◽  
Transport Analysis ◽  
New Form ◽  
Region Ii

Performance of vehicle turn and lane change can be evaluated by cornering stiffness. One of many factors affecting the cornering stiffness is belt angle. In 1998, Koishi et al [1] published the findings of cornering stiffness when belt angle is at 0 and 20 degrees, using a finite element code PAM-SHOCK. Results from two cases only are not enough completing the parametric study. With better hardware and software available today than before, the same tire model is re-visited, using new form of numerical procedure — a mixed Eulerian/Langrangian formulation called steady state transport analysis in ABAQUS. Cornering stiffness at the range of 0 to 40 degree belt angle with 5 degree increment is calculated. The results show that three distinct regions exist. At Region I, in which the belt angle ranges from 0–10 degrees, the cornering stiffness increases as the belt angle increases. The cornering stiffness maximizes out and remains flat at Region II, when belt angle is between 10 to 25 degrees. Cornering stiffness decreases as the belt angle increases in Region III, where the belt angle is larger than 25 degree. The existence of Region II may explain the fact that manufacturers prefer around 20 degree belt angle for their tire designs: maximum cornering stiffness and its insensitivity to the belt angle variation. The plot of the predicted ply steer in this study agrees reasonably well with a published experimental data.

Plasmodium falciparum EBA-175 kDa protein peptides which bind to human red blood cells

Parasitology ◽  
2000 ◽  
Vol 120 (3) ◽  
pp. 225-235 ◽  
Author(s):  
L. E. RODRIGUEZ ◽  
M. URQUIZA ◽  
M. OCAMPO ◽  
J. SUAREZ ◽  
H. CURTIDOR ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Binding Activity ◽  
Ligand Interaction ◽  
Merozoite Invasion ◽  
Human Red Blood Cells ◽  
Affinity Constants ◽  
Region I ◽  
Binding Peptides ◽  
V Region ◽  
Region Ii

Solid experimental evidence indicates that EBA-175 is used as a ligand by the Plasmodium falciparum merozoite to bind to human RBC, via different binding processing fragments. Using synthetic peptides and specific receptor-ligand interaction methodology, we have identified 6 high-activity binding sequences from the EBA-175 CAMP strain; peptide 1758 (KSYGTPDNIDKNMSLIHKHN), located in the so-called region I for which no binding activity has been reported before, peptides 1779 (NIDRIYDKNLLMIKEHILAI) and 1783 (HRNKKNDKLYRDEWWKVIKK), located in region II, in a sub-region known as 5′ Cys F2, previously reported as being a binding region, and peptides 1814 (DRNSNTLHLKDYRNEENERH), 1815 (YTNQNINISQERDLQKHGFH) and 1818 (NNNFNNIPSRYNLYDKKLDL), in region III–V where antibodies inhibit merozoite invasion of erythrocytes. The affinity constants were between 60 and 180 nM and the critical amino acids involved in the binding were identified. The binding of these peptides to enzyme-treated RBC was analysed; binding of peptide 1814, located in the III–V region, was found to be sialic acid dependent. Some of these high binding peptides were able to inhibit in vitro merozoite invasion and to block the binding of recombinant RII-EBA to RBC. Several of these peptides are located in regions recognized by protective immune clusters of merozoites (ICMs) eluted antibodies.

Giant dielectric constant and high-temperature dielectric relaxation properties in La-doped SrTiO3 ceramics

2020 ◽  
pp. 2150046
Author(s):  
Tianyang Liu ◽  
Xiaofei Wang ◽  
Congcong Li ◽  
Bowen Shen ◽  
Mingyan Yao ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
High Temperature ◽  
Temperature Region ◽  
Relaxation Processes ◽  
Doping Amount ◽  
Solid State Method ◽  
Giant Dielectric ◽  
Region I ◽  
Giant Dielectric Constant ◽  
Region Ii

[Formula: see text] (SLTO) ceramics ([Formula: see text] = 0.05, 0.10, 0.15) were prepared with giant dielectric constant by the traditional solid-state method at 1350[Formula: see text]C. The temperature dependence of the dielectric constant was obtained at the temperature ranging from 29[Formula: see text]C to 500[Formula: see text]C and the frequency ranging from 2 kHz to 2 MHz. Two sets of relaxation peaks appear in the low temperature (region I) and the high temperature (region II), respectively. For region I, we conclude that the relaxation behavior is related to the oxygen vacancy migration. For region II, the two relaxation processes are caused by grain boundary for high frequency and Sr or Ti defects at grain interior for low frequency. With the doping amount reaching 0.15, the relaxation peaks disappear and become a common phase transition because of the aggravation of lattice distortion. These possible physical mechanisms of two sets of relaxation peaks are briefly discussed.

Design and Implementation of a Site for a One-Ångstrom TEM

1997 ◽  
Vol 3 (S2) ◽  
pp. 1177-1178
Author(s):  
John H. Turner ◽  
M.A. O'Keefe ◽  
M.A. O'Keefe
Keyword(s):  
Field Emission ◽  
Acoustic Noise ◽  
Mechanical Vibration ◽  
Region I ◽  
Critical Requirement ◽  
The One ◽  
A Site ◽  
Region Ii ◽  
Critical Direction ◽  
Suitable Environment

The National Center for Electron Microscopy has recently acquired a field-emission TEM to form thebasis of a project to achieve a resolution of one Ångstrom. To reach this resolution, both instrumental and environmental factors need to be considered. We have designed and constructed a new building to provide a suitable environment for this instrument, with emphasis on providing isolation from external influences detrimental to the achievement of ultra-high resolution. Such influences include mechanical vibration, temperature fluctuations, acoustic noise, and stray electromagnetic fields.The microscope chosen for the one-Ångstrom project is a Philips CM300 Ultra-Twin equipped with a field-emission gun. Pre-installation specifications provided by Philips for this 1.7Å-resolution TEM specify maximum-allowable values for vibration levels in three mutually-perpendicular directions. In the most critical direction (console left to right), vibration is required to remain below 0.8)μm/sec in the frequency range from 1Hz to 5Hz, although allowed to rise to 6μm/sec above 10Hz (Region I in fig. 1). Even when resolution is not a critical requirement, vibration must be minimized at 2.5Hz (Region II in fig.1).

scholarly journals Regional Characteristics of Long-Term Variability of Summer Precipitation in the Poyang Lake Basin and Possible Links with Large-Scale Circulations

Atmosphere ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1033
Author(s):  
Hua Zhu ◽  
Handan He ◽  
Hongxiang Fan ◽  
Ligang Xu ◽  
Jiahu Jiang ◽  
...  
Keyword(s):  
Large Scale ◽  
Poyang Lake ◽  
Summer Precipitation ◽  
Climate Indices ◽  
Lake Basin ◽  
Regional Characteristics ◽  
Poyang Lake Basin ◽  
Region I ◽  
Region Ii

Understanding the spatiotemporal regime of summer precipitation at local scales plays a key role in regional prevention and mitigation of floods disasters and water resources management. Previous works focused on spatiotemporal characteristics of a region as a whole but left the influence of associated physical factors on sub-regions unexplored. Based on the precipitation data of 77 meteorological stations in the Poyang Lake basin (PYLB) from 1959 to 2013, we have investigated regional characteristics of summer precipitation in the PYLB by integrating the rotated empirical orthogonal function (REOF) analysis with hierarchical clustering algorithm (HCA). Then the long-term variability of summer precipitation in sub-regions of the PYLB and possible links with large-scale circulations was investigated using multiple trend analyses, wavelet analysis and correlation analysis. The results indicate that summer precipitation variations in the PYLB were of very striking regional characteristics. The PYLB was divided into three independent sub-regions based on two leading REOF modes and silhouette coefficient (SC). These sub-regions were located in northern PYLB (sub-region I), central PYLB (sub-region II), and southern PYLB (sub-region III). The summer precipitation in different sub-regions exhibited distinct variation trends and periodicities, which was associated with different factors. All sub-regions show no trends over the whole period 1959–2013, rather they show trends in different periods. Trends per decade in annual summer precipitation in sub-region I and sub-region II were consistent for all periods with different start and end years. The oscillations periods with 2–3 years were found in summer precipitation of all the three sub-regions. Summer precipitation in sub-region I was significantly positively correlated with the previous Indian Ocean Dipole (IOD) event, but negatively correlated with East Asian Summer Monsoon (EASM). While summer precipitation in sub-region II and sub-region III showed weak teleconnections with climate indices. All of the results of this study are conducive to further understand both the regional climate variations in the PYLB and response to circulation patterns variations.

scholarly journals DNase I footprinting shows three protected regions in the promoter of the rRNA genes of Xenopus laevis.

1985 ◽  
Vol 5 (2) ◽  
pp. 313-319 ◽  
Author(s):  
M Dunaway ◽  
R H Reeder
Keyword(s):  
Xenopus Laevis ◽  
Base Pair ◽  
Transcription Initiation ◽  
Protein S ◽  
Dnase I ◽  
Rrna Genes ◽  
Xenopus Laevis Oocytes ◽  
Dnase I Footprinting ◽  
Region I ◽  
Region Ii

Extracts prepared from Xenopus laevis oocytes contain a protein(s) which specifically protects three discrete regions of the RNA polymerase I promoter from digestion by DNase I. Protected region I, from nucleotide +15 to nucleotide -10, spans the site of transcription initiation. Protected region II extends from nucleotide -70 to nucleotide -100 relative to initiation, falling within a 42-base-pair sequence which is homologous to the 60/81-base-pair repeated elements which occur outside of the promoter in the spacer. Protected region III is upstream of region II, from nucleotide -120 to nucleotide -140. All three regions correlate with sequences known from deletion studies to be important for promoter function. Deletion mutants which retain either region I or regions II and III together footprint normally. Deletion of region III, however, reduces but does not eliminate footprinting on region II, suggesting either that one protein binds to both regions or that the proteins which bind to these sites interact with each other.

Numerical Analysis on the Factors Affecting the Hydrodynamic Performance for the Parallel Surfaces With Microtextures

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Lei Wang ◽  
Wenzhong Wang ◽  
Hui Wang ◽  
Tianbao Ma ◽  
Yuanzhong Hu
Keyword(s):  
Numerical Analysis ◽  
Present Model ◽  
Surface Deformation ◽  
Numerical Procedure ◽  
Hydrodynamic Pressure ◽  
Hydrodynamic Performance ◽  
Factors Affecting ◽  
Cavitation Pressure ◽  
Parallel Surfaces ◽  
Semianalytical Method

A numerical analysis on the factors affecting the hydrodynamic performance for parallel surfaces with microtextures is presented in this paper. The semianalytical method and fast Fourier transform technique are implemented in the analysis. The numerical procedure is validated by comparing the results from the present model with the analytical solutions for the lubrication problem in an infinitewide sliding bearing with step-shaped textures. The numerical results show that the hydrodynamic performance can be greatly affected by the factors, such as the boundary conditions, cavitation pressure, microtextures, surface deformation, etc. This study can be of a great help for better understanding the mechanism of hydrodynamic pressure generated between parallel surfaces and realistically evaluating the improvement of tribological performance caused by textures.

scholarly journals Differential Roles of Individual Domains in Selection of Secretion Route of a Streptococcus parasanguinis Serine-Rich Adhesin, Fap1

2007 ◽  
Vol 189 (21) ◽  
pp. 7610-7617 ◽  
Author(s):  
Qiang Chen ◽  
Baiming Sun ◽  
Hui Wu ◽  
Zhixiang Peng ◽  
Paula M. Fives-Taylor
Keyword(s):  
Signal Peptide ◽  
Wild Type ◽  
Secretion Pathway ◽  
C Terminus ◽  
Region I ◽  
Minimal Sequences ◽  
Region Ii ◽  
Dependent Pathway ◽  
Selection Of ◽  
Streptococcus Parasanguinis

ABSTRACT Fimbria-associated protein 1 (Fap1) is a high-molecular-mass glycosylated surface adhesin required for fimbria biogenesis and biofilm formation in Streptococcus parasanguinis. The secretion of mature Fap1 is dependent on the presence of SecA2, a protein with some homology to, but with a different role from, SecA. The signals that direct the secretion of Fap1 to the SecA2-dependent secretion pathway rather than the SecA-dependent secretion pathway have not yet been identified. In this study, Fap1 variants containing different domains were expressed in both secA2 wild-type and mutant backgrounds and were tested for their ability to be secreted by the SecA- or SecA2-dependent pathway. The presence or absence of the cell wall anchor domain (residues 2531 to 2570) at the C terminus did not alter the selection of the Fap1 secretion route. The Fap1 signal peptide (residues 1 to 68) was sufficient to support the secretion of a heterologous protein via the SecA-dependent pathway, suggesting that the signal peptide was sufficient for recognition by the SecA-dependent pathway. The minimal sequences of Fap1 required for the SecA2-dependent pathway included the N-terminal signal peptide, nonrepetitive region I (residues 69 to 102), and part of nonrepetitive region II (residues 169 to 342). The two serine-rich repeat regions (residues 103 to 168 and 505 to 2530) were not required for Fap1 secretion. However, they were both involved in the specific inhibition of Fap1 secretion via the SecA-dependent pathway.

scholarly journals Polymorphism of Repeated Regions of Pertactin in Bordetella pertussis, Bordetella parapertussis, andBordetella bronchiseptica

2000 ◽  
Vol 68 (8) ◽  
pp. 4815-4817 ◽  
Author(s):  
Caroline Boursaux-Eude ◽  
Nicole Guiso
Keyword(s):  
Membrane Protein ◽  
Outer Membrane ◽  
Bordetella Pertussis ◽  
Outer Membrane Protein ◽  
Protective Immunity ◽  
Bordetella Bronchiseptica ◽  
Bordetella Parapertussis ◽  
Region I ◽  
Region Ii

ABSTRACT Pertactin is an outer membrane protein expressed byBordetella pertussis, Bordetella parapertussis, and Bordetella bronchiseptica that induces protective immunity to Bordetella infections. The immunodominant and immunoprotective epitopes of pertactin include two repeated regions, I and II. Comparison of these two repeated regions showed that B. parapertussis pertactin is invariant, whereas B. pertussis pertactin varies mostly in region I and B. bronchiseptica pertactin varies in both repeated regions I and II, but mostly in region II. These differences may result from specific characteristics of these Bordetella species.

scholarly journals Mutations in the N-Terminal Domains of Nectin-1 and Nectin-2 Reveal Differences in Requirements for Entry of Various Alphaherpesviruses and for Nectin-Nectin Interactions

2002 ◽  
Vol 76 (24) ◽  
pp. 12940-12950 ◽  
Author(s):  
Frank Struyf ◽  
Wanda M. Martinez ◽  
Patricia G. Spear
Keyword(s):  
Pseudorabies Virus ◽  
Normal Function ◽  
Viral Glycoprotein ◽  
Bovine Herpesvirus 1 ◽  
Single Nucleotide ◽  
Region I ◽  
Mediate Cell ◽  
Simplex Virus ◽  
Mutant Receptors ◽  
Region Ii

ABSTRACT Nectin-1 and nectin-2 are related molecules that can function with different specificities as entry receptors for mammalian alphaherpesviruses through interaction with viral glycoprotein D (gD). The normal function of members of the nectin family is to mediate cell-cell adhesion through homotypic and heterotypic nectin-nectin interactions in cadherin-based adherens junctions. We examined mutations in three equivalent regions of the N-terminal V-like domains of nectin-1 and nectin-2 to test the effects on entry of various alphaherpesviruses, nectin-nectin interactions, and interactions of the mutant nectins with gD. Mutations in region I previously shown to severely impair herpes simplex virus (HSV) entry activity, but not pseudorabies virus (PRV) or bovine herpesvirus 1 (BHV-1) entry, did not reduce homotypic trans interactions for either nectin-1 or nectin-2 or binding of nectin-3 to nectin-1. Mutations in region II, patterned after a reported single-nucleotide polymorphism in nectin-2, enhanced intracellular accumulation of both nectin-1 and nectin-2 and had a deleterious effect on all of the activities under study. Mutations in region III previously shown to reduce homotypic trans interactions of nectin-2 impaired the entry of PRV and BHV-1 when introduced into either nectin-1 or nectin-2, but only the nectin-2 mutation reduced HSV entry activity. Binding of nectin-1 to nectin-3 was not affected. Effects of the nectin-1 and nectin-2 mutations on interactions with gD did not necessarily correlate with entry activity of the mutant receptors. We can conclude that structural requirements for HSV entry, PRV and BHV-1 entry, and homotypic and heterotypic trans interactions are all different despite the previously reported ability of HSV and HSV gD to inhibit trans interactions.

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