scholarly journals On Deformability of Crane Metallic Structures

2018 ◽  
Vol 251 ◽  
pp. 03035 ◽  
Author(s):  
Anatoly Vershinsky ◽  
Aleksandr Shubin ◽  
Aleksander Masyagin
Keyword(s):  
Life Cycle ◽  
Specific Interaction ◽  
Experimental Studies ◽  
Overhead Crane ◽  
Metallic Structure ◽  
Metallic Structures ◽  
Beam Elements ◽  
Residual Welding ◽  
Dimensional Parameters

Problems of metallic crane structure deformability are considered. This paper contains results of experimental studies on deformability of overhead crane beam elements. These studies take into account the specific interaction between stresses arising from the product’s exposure to loads at various stages of its life cycle, from manufacturing to operation, and residual welding stresses. Recommendations are provided to help stabilize the dimensional parameters of a crane metallic structure.

Modeling the operation of structures made of dispersed-reinforced concrete with an alternating dynamic load of high intensity

2021 ◽  
Vol 14 (3) ◽  
pp. 36-44
Author(s):  
S. Nikolenko ◽  
Svetlana Sazonova ◽  
Viktor Asminin
Keyword(s):  
Reinforced Concrete ◽  
Dynamic Load ◽  
High Intensity ◽  
Concrete Beam ◽  
Static Load ◽  
Dynamic Compression ◽  
Experimental Studies ◽  
Reinforced Concrete Beam ◽  
Beam Elements ◽  
Laminated Structures

A study of the properties of dispersed-reinforced concrete and a study of the effect of dispersed reinforcement on the operation of structures was carried out, mainly with a static load of the same sign. Based on the results of experimental studies, a comparison was made of the work of dispersed-laminated structures under alternating dynamic action of high intensity with the work of reinforced concrete beam elements under similar influences. The results of experimental studies of cubes and prisms for static and dynamic compression are also presented. The results of experimental studies allow us to conclude that there is a significant effect of dispersed reinforcement on the operation of structures under the investigated influences and the feasibility of combined reinforcement of structures. The use of dispersed reinforcement in structures will increase the resistance of structures to such influences.

Stochastic models in cell kinetics

1988 ◽  
Vol 25 (A) ◽  
pp. 91-111
Author(s):  
Peter J. Brockwell
Keyword(s):  
Life Cycle ◽  
Stochastic Models ◽  
Death Rate ◽  
Cell Kinetics ◽  
Branching Processes ◽  
Experimental Studies ◽  
Renewal Theory ◽  
Biological Cell ◽  
Age Dependent

We discuss the role of stochastic processes in modelling the life-cycle of a biological cell and the growth of cell populations. Results for multiphase age-dependent branching processes have proved invaluable for the interpretation of many of the basic experimental studies of the life-cycle. Moreover problems from cell kinetics, in particular those related to diurnal rhythm in cell-growth, have stimulated research into ‘periodic' renewal theory, and the asymptotic behaviour of populations of cells with periodic death rate.

scholarly journals SAMHD1 Regulates Human Papillomavirus 16-Induced Cell Proliferation and Viral Replication during Differentiation of Keratinocytes

mSphere ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Claire D. James ◽  
Apurva T. Prabhakar ◽  
Raymonde Otoa ◽  
Michael R. Evans ◽  
Xu Wang ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Human Papillomavirus ◽  
Life Cycle ◽  
Viral Replication ◽  
Cellular Proliferation ◽  
Specific Interaction ◽  
Viral Life Cycle ◽  
Human Papillomaviruses ◽  
Cellular Growth ◽  
Human Papillomavirus 16

ABSTRACT Human papillomaviruses induce a host of anogenital cancers, as well as oropharyngeal cancer (HPV+OPC); human papillomavirus 16 (HPV16) is causative in around 90% of HPV+OPC cases. Using telomerase reverse transcriptase (TERT) immortalized foreskin keratinocytes (N/Tert-1), we have identified significant host gene reprogramming by HPV16 (N/Tert-1+HPV16) and demonstrated that N/Tert-1+HPV16 support late stages of the viral life cycle. Expression of the cellular dNTPase and homologous recombination factor sterile alpha motif and histidine-aspartic domain HD-containing protein 1 (SAMHD1) is transcriptionally regulated by HPV16 in N/Tert-1. CRISPR/Cas9 removal of SAMHD1 from N/Tert-1 and N/Tert-1+HPV16 demonstrates that SAMHD1 controls cell proliferation of N/Tert-1 only in the presence of HPV16; the deletion of SAMHD1 promotes hyperproliferation of N/Tert-1+HPV16 cells in organotypic raft cultures but has no effect on N/Tert-1. Viral replication is also elevated in the absence of SAMHD1. This new system has allowed us to identify a specific interaction between SAMHD1 and HPV16 that regulates host cell proliferation and viral replication; such studies are problematic in nonimmortalized primary keratinocytes due to their limited life span. To confirm the relevance of our results, we repeated the analysis with human tonsil keratinocytes (HTK) immortalized by HPV16 (HTK+HPV16) and observed the same hyperproliferative phenotype following CRISPR/Cas9 editing of SAMHD1. Identical results were obtained with three independent CRISPR/Cas9 guide RNAs. The isogenic pairing of N/Tert-1 with N/Tert-1+HPV16, combined with HTK+HPV16, presents a unique system to identify host genes whose products functionally interact with HPV16 to regulate host cellular growth in keratinocytes. IMPORTANCE HPVs are causative agents in human cancers and are responsible for around of 5% of all cancers. A better understanding of the viral life cycle in keratinocytes will facilitate the development of novel therapeutics to combat HPV-positive cancers. Here, we present a unique keratinocyte model to identify host proteins that specifically interact with HPV16. Using this system, we report that a cellular gene, SAMHD1, is regulated by HPV16 at the RNA and protein levels in keratinocytes. Elimination of SAMHD1 from these cells using CRISPR/Cas9 editing promotes enhanced cellular proliferation by HPV16 in keratinocytes and elevated viral replication but not in keratinocytes that do not have HPV16. Our study demonstrates a specific intricate interplay between HPV16 and SAMHD1 during the viral life cycle and establishes a unique model system to assist exploring host factors critical for HPV pathogenesis.

scholarly journals Evolution of multicellularity in Dictyostelia

2019 ◽  
Vol 63 (8-9-10) ◽  
pp. 359-369 ◽  
Author(s):  
Yoshinori Kawabe ◽  
Qingyou Du ◽  
Christina Schilde ◽  
Pauline Schaap
Keyword(s):  
Life Cycle ◽  
Experimental Studies ◽  
Evolutionary Conservation ◽  
Comparative Genomic ◽  
Camp Signalling ◽  
Life Styles ◽  
Phenotypic Complexity ◽  
Genomic Studies ◽  
Developmental Programme ◽  
Differentiation Pathways

The well-orchestrated multicellular life cycle of Dictyostelium discoideum has fascinated biologists for over a century. Self-organisation of its amoebas into aggregates, migrating slugs and fruiting structures by pulsatile cAMP signalling and their ability to follow separate differentiation pathways in well-regulated proportions continue to be topics under investigation. A striking aspect of D. discoideum development is the recurrent use of cAMP as chemoattractant, differentiation inducing signal and second messenger for other signals that control the developmental programme. D. discoideum is one of >150 species of Dictyostelia and aggregative life styles similar to those of Dictyostelia evolved many times in eukaryotes. Here we review experimental studies investigating how phenotypic complexity and cAMP signalling co-evolved in Dictyostelia. In addition, we summarize comparative genomic studies of multicellular Dictyostelia and unicellular Amoebozoa aimed to identify evolutionary conservation and change in all genes known to be essential for D. discoideum development.

Stochastic models in cell kinetics

1988 ◽  
Vol 25 (A) ◽  
pp. 91-111
Author(s):  
Peter J. Brockwell
Keyword(s):  
Life Cycle ◽  
Stochastic Models ◽  
Death Rate ◽  
Cell Kinetics ◽  
Branching Processes ◽  
Experimental Studies ◽  
Renewal Theory ◽  
Biological Cell ◽  
Age Dependent

We discuss the role of stochastic processes in modelling the life-cycle of a biological cell and the growth of cell populations. Results for multiphase age-dependent branching processes have proved invaluable for the interpretation of many of the basic experimental studies of the life-cycle. Moreover problems from cell kinetics, in particular those related to diurnal rhythm in cell-growth, have stimulated research into ‘periodic' renewal theory, and the asymptotic behaviour of populations of cells with periodic death rate.

Dual-Tree Wavelet Packet Transform for Ultrasonic Data Transmission Through Metal Structures

2015 ◽  
Author(s):  
Jinjiang Wang ◽  
Robert X. Gao ◽  
Xinyao Tang ◽  
Zhaoyan Fan ◽  
Peng Wang
Keyword(s):  
Signal Processing ◽  
Data Transmission ◽  
Signal To Noise Ratio ◽  
Wavelet Packet ◽  
Experimental Studies ◽  
Wavelet Packet Transform ◽  
Signal To Noise ◽  
Metallic Structures ◽  
Time Frequency ◽  
Noise Ratio

Data communication through metallic structures is generally encountered in manufacturing equipment and process monitoring and control. This paper presents a signal processing technique for enhancing the signal-to-noise ratio and high-bit data transmission rate in ultrasound-based wireless data transmission through metallic structures. A multi-carrier coded-ultrasonic wave modulation scheme is firstly investigated to achieve high-bit data rate communication while reducing inter-symbol inference and data loss, due to the inherent signal attenuation, wave diffraction and reflection in metallic structures. To improve the signal-to-noise ratio, dual-tree wavelet packet transform (DT-WPT) has been investigated to separate multi-carrier signals under noise contamination, given its properties of shift-invariance and flexible time frequency partitioning. A new envelope extraction and threshold setting strategy for selected wavelet coefficients is then introduced to retrieve the coded digital information. Experimental studies are performed to evaluate the effectiveness of the developed signal processing method for manufacturing.

Geometric Deformations of Welded Metallic Structures

2014 ◽  
Vol 657 ◽  
pp. 342-347 ◽  
Author(s):  
Andreea Mădălina Ene Căscătău ◽  
Patrice Plassais ◽  
Marian Gheorghe
Keyword(s):  
Experimental Research ◽  
Process Parameters ◽  
Measurement System ◽  
Quality Characteristics ◽  
Welding Robot ◽  
Metallic Structure ◽  
Metallic Structures ◽  
Welded Structure ◽  
Geometric Deformation ◽  
Set Up

Various research on the influence of different process parameters on quality characteristics of metallic structures assembled by welding have been accomplished [1 - 8, etc.]. The deformations of metallic structure components assembled by welding depend on the characteristics of the components, welded gap, welding speed, scheme and time of components fixing, etc. The paper presents the data and main results of an experimental research on the influence of two process parameters - the welding gap and the fixing time of the components - on the geometric deformations of certain metallic structure components in industrial conditions. Complex experiment and set-up including industrial welding robot and advanced measurement system have been designed and used. The geometric deformations of the welded metallic structure components are caused by forces and phenomenon heating - cooling, i.e. dilatation - contraction, respectively, acting during the periods of fixing - welding, fixing - cooling, cooling without fixing. Relevant dependences between the geometric deformation of welded structure and the considered influencing process parameters have been evidenced.

scholarly journals Considerations on the Use of Explosive Substances for the Destruction of Metallic Structures

2019 ◽  
Vol 24 (2) ◽  
pp. 139-144
Author(s):  
Florin Ilie ◽  
Mircea Vladu ◽  
Gabriela Mihăilă-Lică ◽  
Bogdan-Mihai Georgescu
Keyword(s):  
Public Order ◽  
Metallic Materials ◽  
Metallic Elements ◽  
Metallic Structure ◽  
Destructive Effect ◽  
Metallic Structures ◽  
Degree Of Risk ◽  
Explosive Substance ◽  
High Degree

Abstract Incidents with IEDs containing metallic elements in the vicinity of the explosive substance pose a high degree of risk, endangering safety, peace and public order. In such situations, the methods and procedures applied as response by the authorities are cumbersome and risky, given the improvised nature of these incidents. In this paper we intend to analyze the destructive effect of explosive substances on certain metallic materials and we focus on a U-shaped metallic structure.

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