Mechanical factors tune the sensitivity of mdx muscle to eccentric strength loss and its protection by antioxidant and calcium modulators

Preflocculation of filler particles before their addition to pulp stock provides the most viable and practical solution to increase filler content while minimizing strength loss. The characteristics of filler flocs, such as floc size and structure, have a strong influence on preflocculation efficiency. The influence of flocculant systems on the structural characteristics of filler flocs was examined using a mass fractal analysis method. Mass fractal dimensions of filler flocs under high shear conditions were obtained using light diffraction spectroscopy for three different flocculants. A single polymer (C-PAM), a dual cationic polymer (p-DADMAC/C-PAM) and a C-PAM/micropolymer system were used as flocculants, and their effects on handsheet properties were investigated. The C-PAM/micropolymer system gave the greatest improvement in tensile index. The mass fractal analysis showed that this can be attributed to the formation of highly dense and spherical flocs by this flocculant. A cross-sectional analysis of the handsheets showed that filler flocs with more uniform size were formed when a C-PAM/micropolymer was used. The results suggest that a better understanding of the characteristics of preflocculated fillers and their influence on the properties of paper can be gained based on a fractal analysis.

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Upscaling of foam forming technology for pilot scale

TAPPI Journal ◽

10.32964/tj18.8.461 ◽

2019 ◽

Vol 18 (8) ◽

Cited By ~ 1

Author(s):

JANI LEHMONEN ◽

TIMO RANTANEN ◽

KARITA KINNUNEN-RAUDASKOSKI

Keyword(s):

Production Efficiency ◽

Strength Loss ◽

Pilot Scale ◽

Foam Density ◽

Forming Process ◽

Production Scale ◽

Forming Technology ◽

Wet Pressing ◽

Foam Forming ◽

Board Industry

The need for production cost savings and changes in the global paper and board industry during recent years have been constants. Changes in the global paper and board industry during past years have increased the need for more cost-efficient processes and production technologies. It is known that in paper and board production, foam typically leads to problems in the process rather than improvements in production efficiency. Foam forming technology, where foam is used as a carrier phase and a flowing medium, exploits the properties of dispersive foam. In this study, the possibility of applying foam forming technology to paper applications was investigated using a pilot scale paper forming environment modified for foam forming from conventional water forming. According to the results, the shape of jet-to-wire ratios was the same in both forming methods, but in the case of foam forming, the achieved scale of jet-to-wire ratio and MD/CD-ratio were wider and not behaving sensitively to shear changes in the forming section as a water forming process would. This kind of behavior would be beneficial when upscaling foam technology to the production scale. The dryness results after the forming section indicated the improvement in dewatering, especially when foam density was at the lowest level (i.e., air content was at the highest level). In addition, the dryness results after the pressing section indicated a faster increase in the dryness level as a function of foam density, with all density levels compared to the corresponding water formed sheets. According to the study, the bonding level of water- and foam-laid structures were at the same level when the highest wet pressing value was applied. The results of the study show that the strength loss often associated with foam forming can be compensated for successfully through wet pressing.

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Does kraft hardwood and softwood pulp viscosity correlate to paper properties?

TAPPI Journal ◽

10.32964/tj15.10.643 ◽

2016 ◽

Vol 15 (10) ◽

pp. 643-651 ◽

Cited By ~ 1

Author(s):

ROBERT J. OGLESBY ◽

HUMPHREY J. MOYNIHAN ◽

RICARDO B. SANTOS ◽

ASHOK GHOSH ◽

PETER W. HART

Keyword(s):

Physical Properties ◽

Strength Loss ◽

Strength Properties ◽

Clear Correlation ◽

Paper Properties ◽

Physical Strength ◽

Pulp Viscosity ◽

Softwood Pulp ◽

The Impact ◽

Mechanical Factors of Infl uence on Biological Effi ciency of Solanum Nigrum L.

Agricultural science and practice ◽

10.15407/agrisp1.02.020 ◽

2014 ◽

Vol 1 (2) ◽

pp. 20-23

Author(s):

O. Ivashchenko ◽

O. Ivashchenko

Keyword(s):

Solanum Nigrum ◽

Black Nightshade ◽

Effi Ciency ◽

Weed Plants ◽

Sensitivity Level ◽

Solanum Nigrum L ◽

Small Plot ◽

Mechanical Factors ◽

The Moment ◽

Working Out

Aim. Studying of black nightshade young plants’ response to the induced mechanical stresses. Methods. Researches conducted in small plot fi eld experiments. Results. Change of sensitivity level of Solanum nigrum L. plants depending on phases of their development at the moment of damage of elevated parts has been proven. Owing to loss of the surface capable to photosynthesis, there is an essential decrease in volumes of photosynthesis at plants of weed survived and their possibilities of ontogeny passage. The deep induced dis- stresses reduce biological effi ciency of plants, their ability to accumulate weight and to form seeds and even lead them to death. Conclusions. The defi ned principles of response of weed plants to the induced mechanical dis-stresses are can be used for working out and ecological receptions of crops protection from weeds.

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Microbiology, Histopathology, and Radiographic Findings in Silent Sinus Syndrome

American Journal of Rhinology and Allergy ◽

10.1177/1945892421989161 ◽

2021 ◽

pp. 194589242198916

Author(s):

Henry D. Zheng ◽

Jeffrey C. Mecham ◽

Yassmeen Abdel-Aty ◽

Devyani Lal ◽

Michael J. Marino

Keyword(s):

Maxillary Sinusitis ◽

Dental Disease ◽

Radiographic Findings ◽

Silent Sinus Syndrome ◽

Microbiological Characteristics ◽

Phone Survey ◽

Computed Tomography Scans ◽

History Of ◽

Mechanical Factors ◽

Chronic Maxillary Sinusitis

Background The histopathology and microbiology associated with silent sinus syndrome (SSS) have not been well described. Objective This study details the histopathological and microbiological characteristics in addition to radiographic findings of SSS in comparison to those of chronic maxillary sinusitis (CRS). Methods 42 patients diagnosed with SSS at Mayo Clinic Hospital in Arizona were identified. Paranasal computed tomography scans of the 42 SSS patients as well as 42 matched CRS patients were analyzed in order to assess differences in the prevalence of septal spurs/deviation. 20 of the SSS patients and 19 of the matched CRS patients also had histopathology and microbiology reports, which were compiled and summarized. Additionally, 19 SSS and 19 matched CRS patients were contacted via phone survey for a more complete patient history regarding maxillary dental disease/surgery. Results SSS patients have a significantly higher prevalence of septal spurs/deviation than CRS patients. The microbiomes of SSS patients more closely resemble those of healthy controls than those of CRS patients. Analysis of the histopathology of SSS reveals chronic, non-specific inflammation similar to that seen in non-eosinophilic CRS without polyps. SSS patients were significantly more likely to have a history of maxillary dental disease requiring surgery. Conclusion These data support the hypothesis that the pathogenesis of SSS is more likely due to anatomical/mechanical factors than inflammatory/microbiological factors.

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Keloidal pathophysiology: Current notions

Scars Burns & Healing ◽

10.1177/2059513120980320 ◽

2021 ◽

Vol 7 ◽

pp. 205951312098032

Author(s):

Chenyu Huang ◽

Rei Ogawa

Keyword(s):

Web Of Science ◽

English Literature ◽

The Body ◽

Mechanical Forces ◽

Healthy Skin ◽

Level Of Evidence ◽

Extracellular Matrix Components ◽

Keloid Formation ◽

Mechanical Factors ◽

Pathological Scar

Introduction: Keloids are pathological scars that are notorious for their chronic and relentless invasion into adjacent healthy skin, with commonly seen post-therapeutic recurrence after monotherapies. Methods: An English literature review on keloid pathophysiology was performed by searching the PubMed, Embase and Web of Science databases, to find out the up-to-date relevant articles. The level of evidence was evaluated based on the included studies with the highest level of evidence first. Results: Keloid morphology, signs, symptoms and the histopathological changes that occur in the local cells and extracellular matrix components are described. The theories on the pathophysiology of keloidogenesis that have been proposed to date are also covered; these include endocrinological, nutritional, vascular, and autoimmunological factors. In addition, we describe the local mechanical forces (and the mechanosignalling pathways by which these forces shape keloid cell activities) that promote keloid formation and determine the direction of invasion of keloids and the body sites that are prone to them. Conclusion: A better understanding of this pathological entity, particularly its mechanobiology, will aid the development of new diagnostic and therapeutic strategies for use in the clinic to prevent, reduce or even reverse the growth of this pathological scar. Lay Summary Keloids are skin scars that are famous for their chronic invasion into healthy skin, with commonly seen recurrence after surgeries. Cells such as lymphocytes, macrophages, mast cells and endothelial cells are involved in keloid growth. Particularly, endocrinological, nutritional, vascular, autoimmunological and mechanical factors actively take part in keloid progression.

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Review on pollutant dispersion in urban areas-part A: Effects of mechanical factors and urban morphology

Building and Environment ◽

10.1016/j.buildenv.2020.107534 ◽

2021 ◽

Vol 190 ◽

pp. 107534

Author(s):

Zhengtong Li ◽

Tingzhen Ming ◽

Shurong Liu ◽

Chong Peng ◽

Renaud de Richter ◽

...

Keyword(s):

Urban Areas ◽

Pollutant Dispersion ◽

Urban Morphology ◽

Mechanical Factors

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Durability of Red Mud Based Geopolymer Paste in Acid Solutions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.866.99 ◽

2016 ◽

Vol 866 ◽

pp. 99-105 ◽

Cited By ~ 3

Author(s):

Smita Singh ◽

M.U. Aswath ◽

R.V. Ranganath

Keyword(s):

Mechanical Properties ◽

Acetic Acid ◽

Fly Ash ◽

Red Mud ◽

Acetic Acid Solution ◽

Strength Loss ◽

Acid Solutions ◽

Test Results ◽

Acid Attack ◽

Geopolymer Paste

The present investigation is on the effect of red mud on the mechanical properties and durability of the geopolymer paste in sulphuric and acetic acid solution. Red mud and fly ash were used to form the geopolymer paste along with the alkalies. The variation of red mud in the paste composition was from 0% to 90%. Cylindrical shaped specimens of 1 inch diameter and 1 inch height were prepared. The specimens were immersed in 5% sulphuric acid and 5% acetic acid for 1, 7, 14, 28, 56 and 84 days and tested for weight loss, visual deformation, strength loss and colour of the solvent, based on the procedure specified by ASTM C 267 – 01. SEM/EDX Tests were performed on the geopolymer specimens. Test results show that initially, the strength of the geopolymer increased upon the addition of red mud. The strength was maximum when the percentage of red mud was 30%. The maximum strength obtained was 38 MPa for the paste containing 30% red mud using 10M alkali solution as against 31.69 MPa, when only fly ash was used. Geopolymer paste containing 30% and 50% red mud showed better resistance to acid attack. The strength loss was minimum for the samples containing 30% red mud in both inorganic and organic acid i.e. sulphuric and acetic acid.

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Heat Aged Tensile Strength Retention of Poly (p-phenylene terephthalamide) Sewing Thread

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892500800300403 ◽

2008 ◽

Vol 3 (4) ◽

pp. 155892500800300 ◽

Cited By ~ 4

Author(s):

Walter R. Hall ◽

Warren F. Knoff

Keyword(s):

Hydrolytic Degradation ◽

Oxidative Degradation ◽

Thermal Exposure ◽

Strength Loss ◽

Degradation Process ◽

Downstream Processing ◽

Kink Bands ◽

Sewing Thread ◽

Continuous Filament ◽

Strength Retention

The strength retention after exposure to elevated temperature in air of continuous filament and staple spun PPTA sewing thread and the precursor yarns was determined. For both types, the process of converting the greige yarn to thread reduced the amount of strength retained after thermal exposure. The continuous filament products retained more strength than the staple products. The data was fitted to a kinetic rate model in which two strength loss processes occurred. The first process occurred within about the first 5 minutes of thermal exposure and is hypothesized to be hydrolytic degradation. The estimated secondary degradation process activation energy suggests this to be thermo-oxidative degradation. Optical microscopy of filaments indicates a higher level of kink banding and other damage in continuous filament versus staple products and in finished thread versus the precursor yarns. The kink bands and damage are believed to be caused by the staple manufacturing process and the downstream processing of precursor yarn to finished sewing thread. The kink bands and damage are hypothesized to be responsible for the differences in strength retention.

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