Role of cast-in situ slabs in RC frames under low frequency cyclic load

2014 ◽  
Vol 59 ◽  
pp. 28-38 ◽  
Author(s):  
Ning Ning ◽  
Wenjun Qu ◽  
Peng Zhu
Keyword(s):  
Cyclic Load ◽  
Low Frequency ◽  
Rc Frames

Influence of masonry infills on seismic response of RC frames under low frequency cyclic load

2019 ◽  
Vol 183 ◽  
pp. 70-82 ◽  
Author(s):  
Ning Ning ◽  
Zhongguo John Ma ◽  
Pengpeng Zhang ◽  
Dehu Yu ◽  
Jianlang Wang
Keyword(s):  
Seismic Response ◽  
Cyclic Load ◽  
Low Frequency ◽  
Masonry Infills ◽  
Rc Frames

Wave Velocities in Sediments

1990 ◽  
Vol 195 ◽  
Author(s):  
Dominique Marion ◽  
Amos Nur ◽  
Hezhu Yin
Keyword(s):  
Pore Space ◽  
Low Frequency ◽  
Clay Content ◽  
Velocity Versus ◽  
Critical Porosity ◽  
Porous Sandstone ◽  
Linear Fit ◽  
Compressional Velocity

ABSTRACTSystematic relations between porosity and compressional velocity Vp in the three component (sand, grains, clay and brine) systems (1) porous sandstone, (2) sands, and (3) suspensions, were obtained using experimental data and models. In Cemented Shaley Sandstones Vp was found to correlate linearly with porosity and clay content. The velocities in clean sandstones are about 7% higher than those predicted by the linear fit, indicating that a small amount of clay significantly reduces the elastic moduli of sandstones.For uncemented shaley sand, a model for the dependence of sonic velocity and porosity on clay content and compaction was developed for sand with clay dispersed in the pore space and for shale with suspened sand grains. The model closely mimics the experimentally observed minimum for porosity and the peak in velocity versus clay content. The results explain much of the scatter in velocity data in-situ. Velocity in suspensions at ϕ = 39% of grains in brine is close to values predicted by the Reuss (Isostress) average. Velocity dispersion, as suggested by Biot (1956 a,b) is calculated and observed in coarser sediments such as sand, whereas velocities in the finer clay and silt follow Biot's low frequency value.In total, our results provide the complete dependence of velocity on porosity in brine saturated sediment with clays, ranging from pure quartz to pure clay and water. Our results also highlight the crucial role of the critical porosity ϕ at about 39%, and the transition from cemented to uncemented sands.

scholarly journals Comparative Expression of P53 and Survivin Proteins in Phenylhydrazine-Induced Colon Cancer of Rats and the Role of Electromagnetic Field and Broccoli Extract

2021 ◽  
Author(s):  
Aziz Awaad ◽  
Mohamed A. Adly ◽  
Medhat A. Abd ellatef ◽  
Moshira M. Foad
Keyword(s):  
Colon Cancer ◽  
Electromagnetic Field ◽  
Combined Therapy ◽  
Low Frequency ◽  
Survivin Expression ◽  
Cancer Model ◽  
Beneficial Effects ◽  
Anti Cancer

Abstract Cancer constitutes as one of the most serious causes of death worldwide. For example, colon cancer is the second-most dangerous type of cancer, affecting both men and women. Recently, the application of electromagnetic field (EMF) in the treatment of cancer whether alone or in combination with other anti-cancer materials seems to be a promising therapy. Furthermore, broccoli extract which is rich with sulforaphane (sulfur-rich compound) previously used as one of anti-cancer materials. In this context, the current study aimed to investigate the potential beneficial effects of extremely low frequency-EMF (ELF-EMF) application alone and in combination with broccoli extract in the treatment and protection from cancer in phenylhydrazine (PHZ)-induced colon cancer model. To achieve our aims, the histolopathological abnormalities were investigated histologically and the comparative expression of P53 and survivin proteins were investigated immunohistochemically. This report revealed that PHZ injection was able to induce carcinogenicity in the large intestine of rats especially colon. The PHZ-injected group showed abnormal, biochemical, histological and immunohistochemical parameters. Histologically, the treated colon showed high-grade dysplastic lesions that are further considered as carcinoma-in-situ. The expression of P53 in the crypt of colon decreased significantly in the epithelial cells and lamina propria stroma. Contradictory, survivin expression increased in the same regions after animal exposed to PHZ. However, exposure of PHZ-injected animals to ELF-EMF or broccoli extract separately didn't ameliorate the abnormalities produced by PHZ completely. Interestingly, the combination between ELF-EMF and broccoli extract significantly mitigated the effects of PHZ and succeeded in suppressing tumor progression and normalize the expression of P53 and survivin expressions. This study provided important information about expression of important proteins during cancer stages and the role of combined therapy using EMFs and broccoli extract. Furthermore, the expression changes of P53 and survivin proteins might be used as markers in cancer diagnosis and treatment progress.

Calculation-and-experimental estimation of the role of the frequency ratio in changing the endurance at two-frequency deformation modes

2019 ◽  
Vol 85 (1(I)) ◽  
pp. 64-71 ◽  
Author(s):  
M. M. Gadenin
Keyword(s):  
High Frequency ◽  
Experimental Studies ◽  
Low Frequency ◽  
Reduction Factor ◽  
Single Frequency ◽  
Cyclic Loads ◽  
Small Ratio ◽  
Harmonic Components ◽  
Deformation Modes

The cycle configuration at two-frequency loading regimes depends on the number of parameters including the absolute values of the frequencies and amplitudes of the low-frequency and high-frequency loads added during this mode, the ratio of their frequencies and amplitudes, as well as the phase shift between these harmonic components, the latter having a significant effect only with a small ratio of frequencies. Presence of such two-frequency regimes or service loading conditions for parts of machines and structures schematized by them can significantly reduce their endurance. Using the results of experimental studies of changes in the endurance of a two-frequency loading of specimens of cyclically stable, cyclically softened and cyclically hardened steels under rigid conditions we have shown that decrease in the endurance under the aforementioned conditions depends on the ratio of frequencies and amplitudes of operation low-frequency low-cycle and high-frequency vibration stresses, and, moreover, the higher the level of the ratios of amplitudes and frequencies of those stacked harmonic processes of loading the greater the effect. It is shown that estimation of such a decrease in the endurance compared to a single frequency loading equal in the total stress (strains) amplitudes can be carried out using an exponential expression coupling those endurances through a parameter (reduction factor) containing the ratio of frequencies and amplitudes of operation cyclic loads and characteristic of the material. The reduction is illustrated by a set of calculation-experimental curves on the corresponding diagrams for each of the considered types of materials and compared with the experimental data.

{10-12} Twinning Mechanism During In Situ Micro-Tensile Loading of Pure Mg: Role of Basal Slip and Twin-Twin Boundary Interaction

2020 ◽  
Author(s):  
Nicolò Maria della Ventura ◽  
Szilvia Kalácska ◽  
Daniele Casari ◽  
Thomas Edward James Edwards ◽  
Johann Michler ◽  
...  
Keyword(s):  
Twin Boundary ◽  
Basal Slip ◽  
Tensile Loading ◽  
Boundary Interaction

The role of (bio)surfactant sorption in promoting the bioavailability of nutrients localized at the solid-water interface

1999 ◽  
Vol 39 (7) ◽  
pp. 91-98 ◽  
Author(s):  
Ryan N. Jordan ◽  
Eric P. Nichols ◽  
Alfred B. Cunningham
Keyword(s):  
Mass Transfer ◽  
Cell Membrane ◽  
Substrate Concentration ◽  
Water Interface ◽  
Industrial Systems ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Surfactant Sorption

Bioavailability is herein defined as the accessibility of a substrate by a microorganism. Further, bioavailability is governed by (1) the substrate concentration that the cell membrane “sees,” (i.e., the “directly bioavailable” pool) as well as (2) the rate of mass transfer from potentially bioavailable (e.g., nonaqueous) phases to the directly bioavailable (e.g., aqueous) phase. Mechanisms by which sorbed (bio)surfactants influence these two processes are discussed. We propose the hypothesis that the sorption of (bio)surfactants at the solid-liquid interface is partially responsible for the increased bioavailability of surface-bound nutrients, and offer this as a basis for suggesting the development of engineered in-situ bioremediation technologies that take advantage of low (bio)surfactant concentrations. In addition, other industrial systems where bioavailability phenomena should be considered are addressed.

THE ROLE OF BACTERIAL COMMUNITIES ON IN-SITU ARSENIC AND IRON CYCLING IN RIVERBANKS ALONG THE MEGHNA RIVER, BANGLADESH

2020 ◽  
Author(s):  
Kimberly D. Myers ◽  
◽  
Katrina Lee Jewell ◽  
P.S.K. Knappett ◽  
Mehtaz M. Lipsi ◽  
...  
Keyword(s):  
Bacterial Communities ◽  
Iron Cycling

How Artefacts Do Leadership: A Ventriloquial Analysis

2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren
Keyword(s):  
Organizational Communication ◽  
Recent Work ◽  
Distributed Leadership ◽  
Network Theory ◽  
Actor Network Theory ◽  
Fine Grained ◽  
Naturally Occurring ◽  
Human Actors

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.

scholarly journals Phosphorylation of GAPVD1 Is Regulated by the PER Complex and Linked to GAPVD1 Degradation

2021 ◽  
Vol 22 (7) ◽  
pp. 3787
Author(s):  
Hussam Ibrahim ◽  
Philipp Reus ◽  
Anna Katharina Mundorf ◽  
Anna-Lena Grothoff ◽  
Valerie Rudenko ◽  
...  
Keyword(s):  
Circadian Clock ◽  
Transcriptional Repression ◽  
Small Gtpase ◽  
Main Role ◽  
Interacting Proteins ◽  
Casein Kinase 1 ◽  
Bona Fide ◽  
Kinetics Of

Repressor protein period (PER) complexes play a central role in the molecular oscillator mechanism of the mammalian circadian clock. While the main role of nuclear PER complexes is transcriptional repression, much less is known about the functions of cytoplasmic PER complexes. We found with a biochemical screen for PER2-interacting proteins that the small GTPase regulator GTPase-activating protein and VPS9 domain-containing protein 1 (GAPVD1), which has been identified previously as a component of cytoplasmic PER complexes in mice, is also a bona fide component of human PER complexes. We show that in situ GAPVD1 is closely associated with casein kinase 1 delta (CSNK1D), a kinase that regulates PER2 levels through a phosphoswitch mechanism, and that CSNK1D regulates the phosphorylation of GAPVD1. Moreover, phosphorylation determines the kinetics of GAPVD1 degradation and is controlled by PER2 and a C-terminal autoinhibitory domain in CSNK1D, indicating that the regulation of GAPVD1 phosphorylation is a novel function of cytoplasmic PER complexes and might be part of the oscillator mechanism or an output function of the circadian clock.

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