Instrumentation of a Geosynthetic-Reinforced Flexible Pavement System

1997 ◽  
Vol 1596 (1) ◽  
pp. 31-38
Author(s):  
Steven W. Perkins ◽  
Joseph A. Lapeyre
Keyword(s):  
Asphalt Concrete ◽  
Test Section ◽  
Flexible Pavement ◽  
Design Tool ◽  
Life Cycle Costs ◽  
Site Specific ◽  
Program Of Study ◽  
Traffic Loads ◽  
Base Course

Geosynthetics have been proposed and used to reinforce base course layers in flexible pavement sections to reduce base course thickness, or life-cycle costs, or both. Studies show conflicting results regarding the level to which geosynthetics can improve the performance of flexible pavements. To examine the reinforcement role of geosynthetics, a program of study has been initiated to define the mechanisms of base course reinforcement, to define and quantify the effect of site-specific parameters on the level of improvement observed, and to devise a design tool that can be readily applied in practice. This program will eventually involve the instrumentation of a full-scale pavement subjected to moving traffic loads, the success of which is essential to meeting the three objectives. As a first examination of the performance of proposed instruments, a pilot test section was constructed and monitored for approximately 3 months. The test section was chosen and constructed not necessarily to establish geosynthetic performance but rather to evaluate instrument installation techniques and subsequent instrument performance. Instruments designed to measure strain in the geosynthetics, base course, and asphalt concrete were included.

Full-Scale Evaluation of Relatively Thin Airfield Pavements

2020 ◽  
Vol 2674 (10) ◽  
pp. 658-669
Author(s):  
W. Jeremy Robinson ◽  
Jeb S. Tingle ◽  
Carlos R. Gonzalez
Keyword(s):  
Asphalt Concrete ◽  
Test Section ◽  
Concrete Surface ◽  
Full Scale ◽  
Test Items ◽  
Pavement Structures ◽  
Base Course ◽  
And Performance ◽  
Rutting Behavior ◽  
Aggregate Base

A full-scale airfield pavement test section was constructed and trafficked by the U.S. Army Engineer Research and Development Center (ERDC) to evaluate the performance of relatively thin airfield pavement structures. The test section consisted of four test items that included three asphalt pavement thicknesses and two different aggregate base courses. The test items were subjected to simulated aircraft traffic to evaluate their response and performance to realistic aircraft loads. Rutting behavior, instrumentation response, and falling weight deflectometer response were monitored at selected traffic intervals. It was found that the performance of the airfield pavement sections were most sensitive to aggregate base course properties, where a 50% reduction in base course strength resulted in a 99% reduction in allowable passes. The data suggested that when sufficient asphalt thickness is not provided, the failure mechanism shifted from subgrade failure to base course failure, particularly at higher subgrade CBR values. In addition, the number of aircraft passes sustained was less than that predicted by current Department of Defense (DOD) methods that include assumptions of a high-quality aggregate base and a minimum asphalt concrete thickness. The results of this study were used to extend existing DOD pavement design and evaluation techniques to include the evaluation of airfield pavement sections that do not meet the current criteria for aggregate base quality and minimum asphalt concrete surface thickness. These performance data were used to develop a new base failure design curve using existing stress-based design criteria.

scholarly journals Analisis Tebal Perkerasan Lentur Menggunakan Metode AASHTO 1993

2020 ◽  
Vol 4 (1) ◽  
pp. 30-44
Author(s):  
Muhammad Djaya Bakri
Keyword(s):  
Flexible Pavement ◽  
Trial And Error ◽  
Reliability Factor ◽  
Road Pavement ◽  
Traffic Loads ◽  
Base Course ◽  
Trial And Error Method ◽  
Pavement Construction ◽  
Aashto 1993 ◽  
Error Method

Every year there is an increase in the number of students at the Universitas Borneo Tarakan, which naturally requires the addition of campus buildings, including the construction of road infrastructure to support the development of the campus area. This study aims to analyze the needs of the thickness of the new flexible road pavement construction in the campus area by using the AASHTO 1993 method. This method requires a Structural Number (SN) value that can be calculated by nomogram method and trial and error method. The results of the nomogram method get the value of SN total = 2.09 inches, SN2 = 1.59 inches, and SN1 = 1.39 inches, and the trial and error method gets the value of SNTotal = 2.05 inches, SN2 = 1.56 inches, and SN1 = 1.36 inches. To avoid the risk factor of estimating the error of repetition of traffic loads during the life of the plan (W 18), in the calculation of the SN value, the trial and error method needs to include the value of FR (reliability factor) in the calculation of w18 , where the value obtained FR = 2.39 and W18 = 0, 11x10 6 ESAL. Analysis of the thickness of the flexible pavement construction layer using SN values calculated by the nomogram and trial and error method, resulting in a 39 cm thick flexible pavement, with a surface course = 9 cm, sub-base course = 15 cm, and a base course = 15 cm.

scholarly journals Site-specific ubiquitylation acts as a regulator of linker histone H1

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Eva Höllmüller ◽  
Simon Geigges ◽  
Marie L. Niedermeier ◽  
Kai-Michael Kammer ◽  
Simon M. Kienle ◽  
...  
Keyword(s):  
Posttranslational Modifications ◽  
Histone H1 ◽  
Linker Histone ◽  
Active Chromatin ◽  
Site Specific ◽  
Linker Histone H1 ◽  
Fundamental Process ◽  
Core Histones ◽  
Wide Scale

AbstractDecoding the role of histone posttranslational modifications (PTMs) is key to understand the fundamental process of epigenetic regulation. This is well studied for PTMs of core histones but not for linker histone H1 in general and its ubiquitylation in particular due to a lack of proper tools. Here, we report on the chemical synthesis of site-specifically mono-ubiquitylated H1.2 and identify its ubiquitin-dependent interactome on a proteome-wide scale. We show that site-specific ubiquitylation of H1 at position K64 modulates interactions with deubiquitylating enzymes and the deacetylase SIRT1. Moreover, it affects H1-dependent chromatosome assembly and phase separation resulting in a more open chromatosome conformation generally associated with a transcriptionally active chromatin state. In summary, we propose that site-specific ubiquitylation plays a general regulatory role for linker histone H1.

scholarly journals Influential Factors and Evaluation Methods of the Performance of Grouted Semi-Flexible Pavement (GSP)—A Review

2021 ◽  
Vol 11 (15) ◽  
pp. 6700
Author(s):  
Xiaogang Guo ◽  
Peiwen Hao
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Asphalt Concrete ◽  
Cement Mortar ◽  
Road Construction ◽  
Flexible Pavement ◽  
Evaluation Methods ◽  
Influential Factors ◽  
Future Research ◽  
Relative Evaluation

Grouted Semi-flexible Pavement (GSP) is a novel pavement composed of open-graded asphalt concrete grouted with high-fluidity cement mortar. Due to its excellent load-bearing and anti-rutting performance, it has great potential as anti-rutting overlay and surface in road construction. However, the understanding of GSP performance remains limited and pertinent findings are inconsistent. This article aims to provide a systematic literature review for the articles which were published between 2000 and 2020 on GSP, explore the problems in the recent research, identify knowledge gaps, and deliver recommendations for future research. The influential factors and the relative evaluation methods of GSP performance are summarized and discussed in this article.

scholarly journals Studies on the role of actin's aspartic acid 3 and aspartic acid 11 using oligodeoxynucleotide-directed site-specific mutagenesis.

1988 ◽  
Vol 263 (36) ◽  
pp. 19662-19669
Author(s):  
T L Solomon ◽  
L R Solomon ◽  
L S Gay ◽  
P A Rubenstein
Keyword(s):  
Aspartic Acid ◽  
Site Specific

scholarly journals Phosphorylation of the Regulators, a Complex Facet of NF-κB Signaling in Cancer

Biomolecules ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 15
Author(s):  
Aishat Motolani ◽  
Matthew Martin ◽  
Mengyao Sun ◽  
Tao Lu
Keyword(s):  
Transcription Factor ◽  
Cardiovascular Diseases ◽  
Cancer Progression ◽  
Nuclear Factor Kappa B ◽  
Nuclear Factor ◽  
Malignant Diseases ◽  
Future Perspectives ◽  
Post Translational Modifications ◽  
Site Specific

The nuclear factor kappa B (NF-κB) is a ubiquitous transcription factor central to inflammation and various malignant diseases in humans. The regulation of NF-κB can be influenced by a myriad of post-translational modifications (PTMs), including phosphorylation, one of the most popular PTM formats in NF-κB signaling. The regulation by phosphorylation modification is not limited to NF-κB subunits, but it also encompasses the diverse regulators of NF-κB signaling. The differential site-specific phosphorylation of NF-κB itself or some NF-κB regulators can result in dysregulated NF-κB signaling, often culminating in events that induce cancer progression and other hyper NF-κB related diseases, such as inflammation, cardiovascular diseases, diabetes, as well as neurodegenerative diseases, etc. In this review, we discuss the regulatory role of phosphorylation in NF-κB signaling and the mechanisms through which they aid cancer progression. Additionally, we highlight some of the known and novel NF-κB regulators that are frequently subjected to phosphorylation. Finally, we provide some future perspectives in terms of drug development to target kinases that regulate NF-κB signaling for cancer therapeutic purposes.

Molecular modulation of calcium oxalate crystallization

2006 ◽  
Vol 291 (6) ◽  
pp. F1123-F1132 ◽  
Author(s):  
James J. De Yoreo ◽  
S. Roger Qiu ◽  
John R. Hoyer
Keyword(s):  
Molecular Modeling ◽  
Calcium Oxalate ◽  
Stone Formation ◽  
Energy Levels ◽  
Critical Role ◽  
Specific Interactions ◽  
Crystal Surfaces ◽  
Site Specific

Calcium oxalate monohydrate (COM) is the primary constituent of the majority of renal stones. Osteopontin (OPN), an aspartic acid-rich urinary protein, and citrate, a much smaller molecule, are potent inhibitors of COM crystallization at levels present in normal urine. Current concepts of the role of site-specific interactions in crystallization derived from studies of biomineralization are reviewed to provide a context for understanding modulation of COM growth at a molecular level. Results from in situ atomic force microscopy (AFM) analyses of the effects of citrate and OPN on growth verified the critical role of site-specific interactions between these growth modulators and individual steps on COM crystal surfaces. Molecular modeling investigations of interactions of citrate with steps and faces on COM crystal surfaces provided links between the stereochemistry of interaction and the binding energy levels that underlie mechanisms of growth modification and changes in overall crystal morphology. The combination of in situ AFM and molecular modeling provides new knowledge that will aid rationale design of therapeutic agents for inhibition of stone formation.

scholarly journals V(D)J recombination: signal and coding joint resolution are uncoupled and depend on parallel synapsis of the sites.

1993 ◽  
Vol 13 (3) ◽  
pp. 1363-1370 ◽  
Author(s):  
K M Sheehan ◽  
M R Lieber
Keyword(s):  
Genome Stability ◽  
Lymphoid Cells ◽  
Chromosomal Translocations ◽  
Synaptic Inhibition ◽  
Site Specific ◽  
Coding Sequences ◽  
Specific Process ◽  
A Site ◽  
Joint Resolution

V(D)J recombination in lymphoid cells is a site-specific process in which the activity of the recombinase enzyme is targeted to signal sequences flanking the coding elements of antigen receptor genes. The order of the steps in this reaction and their mechanistic interdependence are important to the understanding of how the reaction fails and thereby contributes to genomic instability in lymphoid cells. The products of the normal reaction are recombinant joints linking the coding sequences of the receptor genes and, reciprocally, the signal ends. Extrachromosomal substrate molecules were modified to inhibit the physical synapsis of the recombination signals. In this way, it has been possible to assess how inhibiting the formation of one joint affects the resolution efficiency of the other. Our results indicate that signal joint and coding joint formation are resolved independently in that they can be uncoupled from each other. We also find that signal synapsis is critical for the generation of recombinant products, which greatly restricts the degree of potential single-site cutting that might otherwise occur in the genome. Finally, inversion substrates manifest synaptic inhibition at much longer distances than do deletion substrates, suggesting that a parallel rather than an antiparallel alignment of the signals is required during synapsis. These observations are important for understanding the interaction of V(D)J signals with the recombinase. Moreover, the role of signal synapsis in regulating recombinase activity has significant implications for genome stability regarding the frequency of recombinase-mediated chromosomal translocations.

Research on the Construction Technology of Self-Monitoring Asphalt Concrete

2021 ◽  
Vol 891 ◽  
pp. 205-210
Author(s):  
Yuan Xu
Keyword(s):  
Asphalt Concrete ◽  
Test Section ◽  
Rolling Process ◽  
Construction Technology ◽  
Self Monitoring ◽  
Mixing Effect ◽  
Steel Wheel ◽  
Mixing Method ◽  
Pavement Construction ◽  
Compaction Degree

Combined with the paving of the test section of Self-monitoring Asphalt Concrete, the electrode burying mode of pavement construction is designed according to its characteristics, and the best mixing method and spreading rolling construction technology are compared and analyzed. The results show that the construction structure of the test section is reasonable and feasible, the best mixing effect can be obtained by adding conductive phase material and asphalt at the same time, and the rolling process. The order of rubber wheel and steel wheel compaction has no significant effect on compaction degree.

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