scholarly journals Mechanical variations in proteins with large-scale motions highlight the formation of structural locks

2017 ◽  
Author(s):  
Sophie Sacquin-Mora
Keyword(s):  
Mechanical Properties ◽  
Protein Function ◽  
Large Scale ◽  
Structural Changes ◽  
Coarse Grain ◽  
Local Rigidity ◽  
New Class ◽  
Closed Conformation ◽  
Closed Structure ◽  
The Impact

AbstractProtein function depends just as much on flexibility as on structure, and in numerous cases, a protein’s biological activity involves transitions that will impact both its conformation and its mechanical properties. Here, we use a coarse-grain approach to investigate the impact of structural changes on protein flexibility. More particularly, we focus our study on proteins presenting large-scale motions. We show how calculating directional force constants within residue pairs, and investigating their variation upon protein closure, can lead to the detection of a limited set of residues that form a structural lock in the protein’s closed conformation. This lock, which is composed of residues whose side-chains are tightly interacting, highlights a new class of residues that are important for protein function by stabilizing the closed structure, and that cannot be detected using earlier tools like local rigidity profiles or distance variations maps, or alternative bioinformatics approaches, such as coevolution scores.

Fundamental Study on Elastic Behavior of Large-Scale Floating Coal Stockyard

2016 ◽  
Author(s):  
Hiroaki Eto ◽  
Chiaki Sato ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Tomoyuki Kishida ◽  
...  
Keyword(s):  
Mass Distribution ◽  
Large Scale ◽  
Asia Pacific ◽  
Elastic Behavior ◽  
Loading Conditions ◽  
Floating Structure ◽  
Fundamental Study ◽  
Local Rigidity ◽  
East Kalimantan ◽  
The Impact

This paper proposes a large-scale floating coal stockyard (LFCS) and discusses its elastic behavior. Indonesia has recently become the main country supplying coal in the Asia-Pacific region. However, there is concern that export to Japan will decrease as coal demand increases. Therefore, the trend of coal transport in Indonesia is a very important matter in ensuring the continued stable import of coal to Japan. It is difficult for bulk carriers to traverse the shallow terrain of the seabed of the Markham River in East Kalimantan to reach coastal areas. Additionally, an LFCS can be operated as a relay base for barges, and large coal carriers have been proposed for use in offshore areas. The LFCS is capable of loading, storing, and offloading coal. Installing an LFCS offshore Kalimantan is expected to improve coal transport productivity in the region. Under such circumstances, the design plan proposed in this paper can simultaneously perform independent loading and unloading without interference. The partial mass distribution and local rigidity of the LFCS varies depending on the coal loading conditions. In addition, because the structure has a planar shape, the response of the LFCS showed elastic behavior. Design example of such a huge floating structure with the great difference of the displacement is unparalleled, it is very important to clarify a design fundamental subject. The objectives of this study are to provide a preliminary LFCS design and investigate the impact of varying the mass distribution and local rigidity on not only the distribution of the distortion and internal stress but also on the dynamic hydroelastic motion of the LFCS when it is impacted by waves. Therefore, the wave response of the LFCS was analyzed under different loading conditions.

Structural Modifications of the Aluminium Alloy in Conditions of Additional Shock Impulse Load

2013 ◽  
Vol 592-593 ◽  
pp. 598-601 ◽  
Author(s):  
Volodymyr Hutsaylyuk ◽  
Mykola Czausow ◽  
Lucjan Śnieżek ◽  
Andrii Pylypenko ◽  
Tomasz Ślęzak ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Room Temperature ◽  
Structural Changes ◽  
Physical Nature ◽  
Structural Modifications ◽  
Equilibrium Processes ◽  
Impulse Load ◽  
Aluminum Alloy 2024 ◽  
The Impact

This work has been done to research the physical nature of the mechanism of structural changes of the aluminum alloy 2024-T3 at the conditions of additional impulse load. There was revealed an anomaly growth in plasticity of the material after such type load realization at the room temperature. Based on fractographical research the impact of dynamic non-equilibrium processes on the structural changes of the material and its macro-mechanical properties was analyzed.

scholarly journals Vermont: a multi-perspective visual interactive platform for mutational analysis

2017 ◽  
Author(s):  
Alexandre V Fassio ◽  
Pedro M Martins ◽  
Samuel da S Guimarães ◽  
Sócrates S A Junior ◽  
Vagner S Ribeiro ◽  
...  
Keyword(s):  
Protein Function ◽  
Visual Analytics ◽  
Large Scale ◽  
Mutational Analysis ◽  
Structural Parameters ◽  
Point Mutations ◽  
Huge Amount ◽  
Interactive Visualizations ◽  
And Function ◽  
The Impact

AbstractBackgroundA huge amount of data about genomes and sequence variation is available and continues to grow on a large scale, which makes experimentally characterizing these mutations infeasible regarding disease association and effects on protein structure and function. Therefore, reliable computational approaches are needed to support the understanding of mutations and their impacts. Here, we present VERMONT 2.0, a visual interactive platform that combines sequence and structural parameters with interactive visualizations to make the impact of protein point mutations more understandable.ResultsWe aimed to contribute a novel visual analytics oriented method to analyze and gain insight on the impact of protein point mutations. To assess the ability of VERMONT to do this, we visually examined a set of mutations that were experimentally characterized to determine if VERMONT could identify damaging mutations and why they can be considered so.ConclusionsVERMONT allowed us to understand mutations by interpreting position-specific structural and physicochemical properties. Additionally, we note some specific positions we believe have an impact on protein function/structure in the case of mutation.

Coal Powder and Ethylene-Propylene-Diene Monomer Reinforced Hybrid Polypropylene Composites

2019 ◽  
Vol 956 ◽  
pp. 192-200
Author(s):  
Yu Feng Bai ◽  
Xin Xin Cao ◽  
Ming Lu Xu ◽  
Xiao Fang He ◽  
Guo Hui Cai
Keyword(s):  
Mechanical Properties ◽  
Contact Angle ◽  
Structural Changes ◽  
Mechanical And Thermal Properties ◽  
Ethylene Propylene Diene Monomer ◽  
Initial Decomposition Temperature ◽  
Ethylene Propylene ◽  
Blending Method ◽  
Coal Powder ◽  
The Impact

For the better mechanical and thermal properties of polypropylene (PP), PP sea-island structured composites with elastomer ethylene-propylene-diene monomer (EPDM) and coal powder were prepared by melt-blending method. Coupling agent γ-methacryloxypropyltrimethoxysilane (KH-570) was used as modifier to improve the superficial capacity of coal powder. The structural changes and properties of modified coal powder and composites were characterized and analyzed by Fourier Transform Infrared Spectroscopy (FTIR), surface contact angle analysis, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and mechanical testing. Results show that the modified coal powder has good hydrophobicity and sea-island structure is beneficial in improving the comprehensive performance of composites. The contact angle increases from 33.8° to 91.6° after modification. The initial decomposition temperature (T0) and largest weight loss temperature (Tmd) both have an increase with coal powder content and the maximum are 431.02 °C and 465.33 °C. The mechanical properties tend to go up first and then down with the addition of coal powder. PP/26EPDM/4coal composite has best mechanical properties as well as the impact strength and elongation at break are 60.9 MPa, 615.0%, respectively.

scholarly journals Remote sensing of the impact of flash drought events on terrestrial carbon dynamics over China

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Miao Zhang ◽  
Xing Yuan ◽  
Jason A. Otkin
Keyword(s):  
Remote Sensing ◽  
Soil Moisture ◽  
Large Scale ◽  
Structural Changes ◽  
Terrestrial Ecosystems ◽  
Northern China ◽  
Carbon Dynamics ◽  
Western China ◽  
Terrestrial Carbon ◽  
The Impact

Abstract Background Flash drought poses a great threat to terrestrial ecosystems and influences carbon dynamics due to its unusually rapid onset and increasing frequency in a warming climate. Understanding the response of regional terrestrial carbon dynamics to flash drought requires long-term observations of carbon fluxes and soil moisture at a large scale. Here, MODIS satellite observations of ecosystem productivity and ERA5 reanalysis modeling of soil moisture are used to detect the response of ecosystems to flash drought over China. Results The results show that GPP, NPP, and LAI respond to 79–86% of the flash drought events over China, with highest and lowest response frequency for NPP and LAI, respectively. The discrepancies in the response of GPP, NPP, and LAI to flash drought result from vegetation physiological and structural changes. The negative anomalies of GPP, NPP, and LAI occur within 19 days after the start of flash drought, with the fastest response occurring over North China, and slower responses in southern and northeastern China. Water use efficiency (WUE) is increased in most regions of China except for western regions during flash drought, illustrating the resilience of ecosystems to rapid changes in soil moisture conditions. Conclusions This study shows the rapid response of ecosystems to flash drought based on remote-sensing observations, especially for northern China with semiarid climates. Besides, NPP is more sensitive than GPP and LAI to flash drought under the influence of vegetation respiration and physiological regulations. Although the mean WUE increases during flash drought over most of China, western China shows less resilience to flash drought with little changes in WUE during the recovery stage. This study highlights the impacts of flash drought on ecosystems and the necessity to monitor rapid drought intensification.

Characteristics and Mechanical Properties of Rolling-Element Bearings

2016 ◽  
Vol 8 (3) ◽  
Author(s):  
Lv Haiting
Keyword(s):  
Mechanical Properties ◽  
Load Distribution ◽  
Large Scale ◽  
Roller Bearing ◽  
Rolling Bearing ◽  
Fe Model ◽  
Rolling Bearings ◽  
Angle Variation ◽  
Supporting Structure ◽  
The Impact

Large rolling bearings are mainly used in occasions of low speed and heavy load due to its desirable properties such as large-scale structure and high bearing capacity. Currently, the research emphases of large rolling bearings are focussed on the load distribution, load carrying capacity, fatigue life and structure optimization. Bearings used in heavy vehicles belong to large bearings, whose reliability is also very important. In this paper, the characteristics of the structures of four point angular contact ball bearings and three row cylindrical roller bearing are analyzed. Finite element (FE) model is used to simulate the load distribution and angle variation in the actual working process of a large rolling bearing. In order to analyze the impact of the constraints, the stiffness and the local hard point of the supporting structure on the mechanical properties of large rolling bearings, a series of simplified FE models of large rolling bearing with different constraints and supporting structure has been carried out.

CONNECTION BETWEEN STRUCTURAL CHANGES OF IRRIADIATED POLYETHER ETHER KETONE AND MECHANICAL PROPERTIES

Tribologia ◽  
2018 ◽  
Vol 278 (2) ◽  
pp. 95-101
Author(s):  
Aneta NIEMIEC
Keyword(s):  
Mechanical Properties ◽  
Glass Transition ◽  
Structural Changes ◽  
Radiation Energy ◽  
Degree Of Crystallinity ◽  
Scanning Calorimetry ◽  
Polyether Ether Ketone ◽  
Ether Ketone ◽  
The Impact ◽  
The Degree Of Crystallinity

The article presents the results of research on the impact of structural changes in polyether ether ketone (PEEK) on its mechanical properties. The polymer was exposed to gamma radiation at a dose of 50 and 150 kGy, and the radiation energy was 4 MeV. Changes in the degree of crystallinity and the related changes in the glass transition and melting temperature for the polymer were determined by differential scanning calorimetry (DSC). Mechanical properties were determined using the micro-mentoring method. The tests showed a change in the degree of crystallinity in the range of several degrees and a significant increase in the glass transition temperature. In terms of mechanical properties, the reduction of hardness and Young’s modulus was observed. Observed changes, especially in terms of changes in the structure of the polymer under the influence of radiation, are difficult to explain, which requires conducting further research, especially in the range of irradiation parameters used. Further research is important because PEEK is used in many fields, especially in conditions conducive to corrosion and the influence of radiation.

scholarly journals A Thermo-Mechanical Analysis of Laser Hot Wire Additive Manufacturing of NAB

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1023
Author(s):  
Glenn W. Hatala ◽  
Qian Wang ◽  
Edward W. Reutzel ◽  
Charles R. Fisher ◽  
Jennifer K. Semple
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
Large Scale ◽  
Mechanical Analysis ◽  
Simulation Software ◽  
Aluminum Bronze ◽  
Hot Wire ◽  
Temperature Dependent ◽  
Temperature Dependent Properties ◽  
The Impact

There is increased interest in using nickel aluminum bronze (NAB) alloys in large-scale directed energy deposition additive manufacturing (DEDAM) processes for maritime applications, but one challenge lies in the component distortion that results from residual stress generated during fabrication. This paper describes the development and evaluation of thermo-mechanical simulations for laser hot wire (LHW) DEDAM of NAB to predict part distortion. To account for the dearth of temperature-dependent properties for NAB C95800 in open literature and public databases, temperature-dependent material and mechanical properties for NAB C95800 were experimentally measured using test specimens fabricated with a variety of DEDAM processes. Autodesk’s Netfabb Local Simulation software, a commercial finite-element based AM solver, was employed but with its heat source model modified to accommodate LHW DEDAM’s oscillating laser path and additional energy input supplied by the preheated wire feedstock. Thermo-mechanical simulations were conducted using both the acquired temperature-dependent material and mechanical properties and the constant room-temperature properties to assess the impact on simulation accuracy. The usage of constant properties in the thermo-mechanical analysis resulted in significantly different predicted distortion compared to those using the temperature-dependent properties, at times even predicting substrate displacement in an opposite direction.

scholarly journals Analysis of the prevalence and risk factors of osteoarthritis in a population

2019 ◽  
Vol 13 (2) ◽  
pp. 105-111 ◽  
Author(s):  
O. O. Portyannikova ◽  
S. M. Tsvinger ◽  
A. V. Govorin ◽  
E. N. Romanova
Keyword(s):  
Risk Factors ◽  
Large Scale ◽  
Metabolic Disorders ◽  
Structural Changes ◽  
Professional Activities ◽  
Ethnic Factors ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

The review contains data from large-scale foreign and Russian studies of the epidemiology of osteoarthritis (OA). It considers the role of modifiable and non-modifiable risk factors for OA, such as age, sex, hormonal status, obesity, etc. There are data on genetic susceptibility to OA and on congenital anomalies that contribute to joint structural changes. Data on the impact of racial and ethnic factors on the development and progression of OA are analyzed. The role of metabolic disorders in the pathogenesis of this disease is highlighted. Data on the relationship of OA to patients' professional activities are summarized.

The effect of dispersants on the properties of low-cement concrete for the furnace of smelting of jewelry waste

2021 ◽  
pp. 49-52
Author(s):  
B. L. Krasnyi ◽  
K. I. Ikonnikov ◽  
A. L. Galganova
Keyword(s):  
Mechanical Properties ◽  
Large Scale ◽  
Cement Concrete ◽  
Concrete Mass ◽  
Refractory Crucible ◽  
Ceramic Crucible ◽  
The Impact

Melting in ceramic crucible is one of the stages of recycling jewelry production. Conceptivity of concrete mass plays an important role in molding a large-scale refractory crucible to vibration. The impact of a number of commercially available dispersants (CASTAment FS 10, MELFLUX 1641 F, peramin al 200, FF7 SPEZIAL and PC-1701) on the rheology of the low-cement concrete mass of corundo-mullite-zirconium composition and the physico-mechanical properties of the material are considered. The best results were obtained using the PC-1701 dispersant. 

Sign in / Sign up

Export Citation Format

Share Document