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Skeletal muscle is an adaptive tissue with the ability to regenerate in response to exercise training. Cross-sectional area (CSA) quantification, as a main parameter to assess muscle regeneration capability, is highly tedious and time-consuming, necessitating an accurate and automated approach to analysis. Although several excellent programs are available to automate analysis of muscle histology, they fail to efficiently and accurately measure CSA in regenerating myofibers in response to exercise training. Here, we have developed a novel fully-automated image segmentation method based on neutrosophic set algorithms to analyse whole skeletal muscle cross sections in exercise-induced regenerating myofibers, referred as MyoView, designed to obtain accurate fiber size and distribution measurements. MyoView provides relatively efficient, accurate, and reliable measurements for CSA quantification and detecting different myofibers, myonuclei and satellite cells in response to the post-exercise regenerating process. We showed that MyoView is comparable with manual quantification. We also showed that MyoView is more accurate and efficient to measure CSA in post-exercise regenerating myofibers as compared with Open-CSAM, MuscleJ, SMASH and MyoVision. Furthermore, we demonstrated that to obtain an accurate CSA quantification of exercise-induced regenerating myofibers, whole muscle cross-section analysis is an essential part, especially for the measurement of different fiber-types. We present MyoView as a new tool to quantify CSA, myonuclei and satellite cells in skeletal muscle from any experimental condition including exercise-induced regenerating myofibers.

International audience; In Brazil, most Eucalyptus plantations are located in regions experiencing periods of water shortage, where fertilizers such as potassium (K) are intensively used to achieve high productivity. Recently, sodium (Na) has also been considered a potential nutrient in K-deficient soils. K and Na supply can increase water stress in Eucalyptus grandis trees, which could negatively impact forest productivity over prolonged droughts. Wood properties are determinants of the quality and yield of products. They are important factors to consider when measuring the impacts of silvicultural practices and water deficit on forest productivity. However, alterations in wood properties due to interactions between K/Na fertilization, water availability, and stand age are not well documented.Through annual sampling of E. grandis trees throughout a complete rotation (6 years) in Brazil, we evaluated the interactive effects of K/Na fertilization, water availability, and stand age on stem volume, sapwood/heartwood ratio, wood density, fiber, and vessel features. We also evaluated the relationships between growth rate, wood density, and fiber and vessel features. The split-plot experimental design consisted of two water supply regimes (37% throughfall reduction versus undisturbed throughfall) and three fertilization regimes (K, Na, and control).Until six years of age, K and Na fertilization increased stem volume by 3 and 2-fold, respectively, and only K-fertilized trees affected stem volume by 37% throughfall reduction. Both K and Na detrimentally affected wood density and beneficially affected fiber length. The sapwood/heartwood ratio was highly and negatively related to the growth rate of trees. Wall thickness was not affected by either K or Na. As expected, K and Na affected vessel size due to an increase in basal area growth. However, the effects of Na were more pronounced than those of K. Significant interactions between fertilization and water availability suggest that, under water deficit, wood density will not be affected by K fertilization. In contrast, the effect of Na and control treatments were invariable regardless of water availability.The effects of fertilization on wood properties changed over time, with non-significant effects in the first year and stronger effects from two years of age of trees. The variations in wood density were strongly related to variations in the fiber wall thickness. High increases in basal area growth promoted by K and Na were not related to significant decreases in wood density, but they were related to increases in fiber length. These findings highlight the significant effects of K addition on stem volume without significant losses in wood quality, even under water stress over a complete rotation. The negative impacts observed on wood density and lower productivity in commercial E. grandis plantations with the use of Na as a substitute for K should be considered.

INTRODUCTION AND OBJECTIVE:The novel thulium fiber laser (TFL) has advantages compared to the Holmium laser (HL) including smaller fiber size (150 μm) and higher frequency settings (up to 2000 Hz)....

The locomotor muscle morphology of diving mammals yields insights into how they utilize their environment and partition resources. This study examined a primary locomotor muscle, the longissimus, in three closely related, similarly sized pelagic delphinids (n = 7-9 adults of each species) that exhibit different habitat and depth preferences. The Atlantic spotted dolphin (Stenella frontalis) is a relatively shallow diver, inhabiting continental shelf waters; the striped (Stenella coeruleoalba) and short-beaked common (Delphinus delphis) dolphins are sympatric, deep-water species that dive to different depths. Based upon comparative data from other divers, it was hypothesized that the locomotor muscle of the deepest-diving S. coeruleoalba would exhibit a higher percentage of slow oxidative fibers, larger fiber diameters, a higher myoglobin concentration [Mb], and a lower mitochondrial density than that of the shallow-diving S. frontalis, and that the muscle of D. delphis would display intermediate values for these features. As expected, the locomotor muscle of S. coeruleoalba exhibited a significantly higher proportion of slow (57.3 ± 3.9%), oxidative (51.7 ± 2.5%) fibers and higher [Mb] (8.2 ± 0.7 g/100 g muscle) than that of S. frontalis (41.3 ± 3.9%, 31.0 ± 3.2%, 4.7 ± 0.05 g/100 g muscle, respectively). There were no differences in fiber size or mitochondrial density among these species. Like other deep divers, S. coeruleoalba displayed locomotor muscle features that enhance oxygen storage capacity and metabolic efficiency but did not display features that limit aerobic capacity. These results suggest a previously undescribed muscle design for an active, small-bodied, deep-diving cetacean. HIGHLIGHTS: The locomotor muscle features displayed by the striped dolphin, which are unique among deep divers, enhance oxygen stores but do not limit aerobic capacity. This novel muscle design may facilitate the active lifestyle of this small-bodied deep diver.

Composite materials are extensively used in a wide range of applications. Natural-fiber-reinforced polymer matrix composites play a dominant role in the field of composites. The primary objective of this research was to investigate the effect of fiber size on the tensile properties of natural-fiber-reinforced polymer composites. The composite was fabricated by solution-casting technology using jute, coir and banana fibers, varying the fiber ratio as 3, 2 and 1% (weight/weight) and varying the fiber length as 10, 5 and 1 mm. Taguchi’s design of experiments was followed to study the mechanical characteristics of samples by recording Young’s modulus, modulus of resilience and yield stress through tensile tests. Analysis of variance was used to determine the effect of distinctive parameters on the tensile properties through main-effects plots, contour plots and regression equations. It was concluded from the results that the epoxy/jute sample showed good tensile characteristics followed by the epoxy/coir sample. The epoxy/jute sample, with 10 mm size and 3% fiber ratio, exhibited the highest Young’s modulus of 3568 MPa.

Bacterial nanocellulose (BNC) is a unique natural nanomaterial that shares very few similarities with other natural or industrially produced nanomaterials. BNC can be produced by a variety of bacteria, as a survival aid in different ecological niches. BNC is traditionally produced by static or shaking culture methods, and the ‘mother vinegar’, or biofilm, is a typical example of this product after static vinegar fermentation. BNC has great potential in biomedicine, and recent studies have also demonstrated its use in the papermaking industry. It has nanoscale fiber size and large numbers of free hydroxyl groups, which ensure high inter-fiber hydrogen bonding. Thus, BNC has great potential as a reinforcing material, and is especially applicable for recycled paper and for paper made of nonwoody cellulose fiber. As well as enhancing the strength and durability of paper, modified BNC shows great potential for production of fire resistant and specialized papers. However, the biotechnological aspects of BNC need to be improved to minimize the cost of its production, and to thus make this process economically feasible.

In this paper, a theoretical model for predicting the longitudinal tensile strength of unidirectional fiber reinforced polymer (FRP) composites at different temperatures is established. This model considers the combined effects of temperature, matrix strength, fiber size, fiber volume fraction, and the fiber strength scatter on the tensile strength of unidirectional FRP composites. The model is verified by comparison with available experimental data of carbon fiber and glass fiber reinforced polymer composites at different temperatures. The agreement between the theoretical model and experimental results is found to be satisfactory, which indicates the applicability and reasonability of the model. Particularly, the model has advantages compared with Curtin's model, Gao-Reifsnider's (G-R's) model and Subramanian-Reifsnider's (S-R's) model from the aspects of accuracy and convenience. Furthermore, the influencing factor analysis for unidirectional FRP composites regarding their temperature dependent tensile strength was systematically conducted, which provide better understanding on the strength control mechanism and material design.

Skeletal muscle is an adaptive tissue with the ability to regenerate in response to exercise training. Cross-sectional area (CSA) quantification, as a main parameter to assess muscle regeneration capability, is highly tedious and time-consuming, necessitating an accurate and automated approach to analysis. Although several excellent programs are available to automate analysis of muscle histology, they fail to efficiently and accurately measure CSA in regenerating myofibers in response to exercise training. Here, we have developed a novel fully-automated image segmentation method based on neutrosophic set algorithms to analyse whole skeletal muscle cross sections in exercise-induced regenerating myofibers, referred as MyoView, designed to obtain accurate fiber size and distribution measurements. MyoView provides relatively efficient, accurate, and reliable measurements for detecting different myofibers and CSA quantification in response to the post-exercise regenerating process. We showed that MyoView is comparable with manual quantification. We also showed that MyoView is more accurate and efficient to measure CSA in post-exercise regenerating myofibers as compared with Open-CSAM, MuscleJ, SMASH and MyoVision. Furthermore, we demonstrated that to obtain an accurate CSA quantification of exercise-induced regenerating myofibers, whole muscle cross-section analysis is an essential part, especially for the measurement of different fiber-types. We present MyoView as a new tool for CSA quantification in skeletal muscle from any experimental condition including exercise-induced regenerating myofibers.

Here we provide a first assessment of microplastics (MPs) in stomach contents of 15 common dolphins (Delphinus delphis) from both single and mass stranding events along the New Zealand coast between 2019 and 2020. MPs were observed in all examined individuals, with an average of 7.8 pieces per stomach. Most MPs were fragments (77%, n = 90) as opposed to fibres (23%, n = 27), with translucent/clear (46%) the most prevalent colour. Fourier transform infrared (FTIR) spectroscopy revealed polyethylene terephthalate (65%) as the most predominant polymer in fibres, whereas polypropylene (31%) and acrylonitrile butadiene styrene (20%) were more frequently recorded as fragments. Mean fragment and fibre size was 584 μm and 1567 μm, respectively. No correlation between total number of MPs and biological parameters (total body length, age, sexual maturity, axillary girth, or blubber thickness) was observed, with similar levels of MPs observed between each of the mass stranding events. Considering MPs are being increasingly linked to a wide range of deleterious effects across taxa, these findings in a typically pelagic marine sentinel species warrants further investigation.

Vitamin D deficiency, which is highly prevalent in the general population, exerts similar deleterious effects on skeletal muscles to those induced by cigarette smoking. We examined whether cigarette smoke (CS) exposure and/or vitamin D deficiency impairs the skeletal muscle hypertrophic response to overload. Male C57Bl/6JolaH mice on a normal or vitamin D-deficient diet were exposed to CS or room air for 18 wk. Six weeks after initiation of smoke or air exposure, sham surgery or denervation of the agonists of the left plantaris muscle was performed. The right leg served as internal control. Twelve weeks later, the hypertrophic response was assessed. CS exposure instigated loss of body and muscle mass, and increased lung inflammatory cell infiltration (P < 0.05), independently of diet. Maximal exercise capacity, whole body strength, in situ plantaris muscle force, and key markers of hypertrophic signaling (Akt, 4EBP1, and FoxO1) were not significantly affected by smoking or diet. The increase in plantaris muscle fiber cross-sectional area in response to overload was attenuated in vitamin D-deficient CS-exposed mice (smoking × diet interaction for hypertrophy, P = 0.03). In situ fatigue resistance was elevated in hypertrophied plantaris, irrespective of vitamin D deficiency and/or CS exposure. In conclusion, our data show that CS exposure or vitamin D deficiency alone did not attenuate the hypertrophic response of overloaded plantaris muscles, but this hypertrophic response was weakened when both conditions were combined. These data suggest that current smokers who also present with vitamin D deficiency may be less likely to respond to a training program.NEW & NOTEWORTHY Plantaris hypertrophy caused by compensatory overload after denervation of the soleus and gastrocnemius muscles showed increased mass and fiber dimensions, but to a lesser extent when vitamin D deficiency was combined with cigarette smoking. Fatigue resistance was elevated in hypertrophied plantaris, irrespective of diet or smoking, whereas physical fitness, hypertrophic markers, and in situ plantaris force were similar. These data showed that the hypertrophic response to overload is attenuated when both conditions are combined. ispartof: JOURNAL OF APPLIED PHYSIOLOGY vol:131 issue:1 pages:339-351 ispartof: location:United States status: published

Unilateral posterior crossbite is a type of malocclusion that involves morpho-functional characteristics of masticatory muscle, such as the masseter: electrophysiological data have shown that the affected side works less than the contralateral muscle, which shows a normal or increased activity, probably in order to compensate for the affected side. The aim of present work was to measure the diameter and the cross-sectional area of ipsilateral and contralateral muscle fibers to verify if hypertrophy and/or hypotrophy take place in this malocclusion. We used immunofluorescence pictures to measure, using ImageJ software, the diameter and the cross-sectional area of fibers from control and crossbite groups, after that, the data were processed to perform statistical analyses. Results show that the fiber diameters of contralateral muscle are larger than the diameters of ipsilateral and control fibers, and that this difference is statistically significant. No statistically significant difference was found between the fiber diameters of the ipsilateral and control muscles. All these data suggest that, during unilateral posterior crossbite, morphological changes take place in the contralateral masseter muscle, which undergoes hypertrophy, probably to compensate for the low activity of the affected muscle.

KEY POINTS A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres. We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function. Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age-matched non-exercisers (75 ± 2 years). Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres. These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age. ABSTRACT We investigated single muscle fibre size and contractile function among three groups of men: lifelong exercisers (LLE) (n = 21, 74 ± 4 years), old healthy non-exercisers (OH) (n = 10, 75 ± 2 years) and young exercisers (YE) (n = 10, 25 ± 1 years). On average, LLE had exercised ∼5 days week-1 for ∼7 h week-1 over the past 53 ± 6 years. LLE were subdivided based on lifelong exercise intensity into performance (LLE-P) (n = 14) and fitness (LLE-F) (n = 7). Muscle biopsies (vastus lateralis) were examined for myosin heavy chain (MHC) slow (MHC I) and fast (MHC IIa) fibre size and function (strength, speed, power). LLE MHC I size (7624 ± 2765 μm2 ) was 25-40% larger (P LLE > YE; P

Here we will review our current activities on the realization of photonic active structures based on biomaterials. Nanofibers of DNA incorporating light-emitting chromophores are reported with enhanced optical emission and lasing properties tailorable by the fiber size and architecture. The research leading to these results has received funding the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 682157, “xPRINT”) and from the Italian Minister of University and Research through the PRIN 201795SBA3 project.

The demand for paper and pulp-derived products to fulfill consumer needs is increasing considerably globally. This work provides a critical overview of the various traditional pulping methods and describes the recent improvements in pulping processes. A comparison of different pulping techniques has shown that the mechanical pulping process produces high pulp yields per unit volume of wood of poor quality (low strength, bonding, fiber morphology, etc.) as compared to chemical pulping methods. The use of semi-chemical pulping is reported as an effective way of overcoming the disadvantages of the mechanical pulping process. Recent modifications of the pulping processes that have happened in the last decade have been discussed and shown to be driven by the desire to save energy and reduce chemical requirements while maximizing pulp yields and quality. With the emergence of bio-based nanotechnology, post-pretreatment of Kraft and sulfite pulps for making nanocellulose and lignin-containing nanocellulose with improved fiber characteristics of fiber size, crystallinity, chemical composition, and fiber surface functionality has been discussed. Furthermore, challenges and prospects of the improvements in pulping processes are highlighted.

There is a growing attention to develop environmental friendly and low-cost materials using renewable sources regarding as environmental awareness and economic issues. So, economic and environmental legislations are playing an important role to use green fibers for production of thermoplastic composites instead of synthetic fibers. Green fibers are promising materials as filler for thermoplastic composites due to their low density, biodegradability, and abundance. Combination of a green fiber and thermoplastic matrix can provide production of sustainable and high-performance composite materials depending on good interfacial adhesion between green fiber and thermoplastic matrix. Compatibility of green fiber with matrix can be enhanced by optimized fiber size and orientation, effective fiber treatment, changes in manufacturing process, and operation conditions. Strong adhesion between fiber and matrix has synergistic effects on the physicomechanical and thermal properties of green fiber thermoplastic composites. With the help of their advantages, green fiber thermoplastic composites are commonly utilized in many applications.

This paper investigates the influence of waste tyre fibres on the geotechnical properties of clayey soil used as a subgrade material. Laboratory California bearing ratio (CBR) tests were conducted for the unsoaked condition as a measurement of pavement performance under the normal rainfall. Three types of tyre fibres as TFA, TFB and TFC used in the present study were mixed in a proportion of 0.25, 0.5, 0.75 and 1% by dry mass of clayey soil. In each test, the specimen was prepared in accordance with the compaction characteristics achieved from the modified compaction energy. The test results reported that the compaction characteristics of cohesive soil were getting increased with an increase in fibre content. In general, regardless of the fibre size, the CBR values get increased with an increase in fibre content. The experimental results showed that clayey soil achieves five times higher CBR value for the addition of 0.75% TFC. From the test results, it can be concluded that the use of waste tyre fibres considerably reduces the pavement thickness and hence reduces the construction cost.

Human skeletal muscle characteristics such as fiber type composition, fiber size and myonuclear content are widely studied in clinical and sports related contexts. Being aware of the methodological and biological variability of the characteristics is a critical aspect in study design and outcome interpretation, but comprehensive data on the variability of morphological features in human skeletal muscle is currently limited. Accordingly, in the present study, m. vastus lateralis biopsies (10 per subject) from young and healthy individuals, collected in a systematic manner, were analyzed for various characteristics using immunohistochemistry (n=7) and SDS-PAGE (n=25). None of the analyzed parameters; fiber type % (FT%), type I and II CSA (fCSA), percentage fiber type area (fCSA%), myosin heavy chain composition (MyHC%), type IIX content, myonuclear content or myonuclear domain varied in a systematic manner longitudinally along the muscle or between the two legs. The average within subject coefficient of variation for FT%, fCSA, fCSA%, and MyHC% ranged between 13-18%, but was only 5% for fiber specific myonuclear content, which reduced the variability for myonuclear domain size to 11-12%. Pure type IIX fibers and type IIX MyHC were randomly distributed and present in

Natural fibers are used as an alternative resource due to environmental issues and petroleum depletion. Over the last few years, roselle plants have been widely exploited as a source of natural fiber. The natural fiber has been able to benefit both the economy and environment. This research presents the effect of fiber size on mechanical and thermal properties of roselle fiber-reinforced polylactide (PLA) composites by using ANSYS software. The purpose of this project was to evaluate the effect of fiber size on the mechanical and thermal properties of roselle fiber-reinforced PLA composites by using ANSYS software. In order to evaluate the effect of fiber size, three parameters were set. An updated three-dimensional finite element model was developed in the ANSYS 16.1 workbench to determine the characterization of the composites under functionally suitable loading conditions. Past researchers have conducted studies on different fiber length and different fiber loading orientations, including different materials widely used in developing countries. The meshing process is important as it indicates a good result between fiber and matrix, which improved the mechanical and thermal properties of the composites in the simulation analysis. The best fiber size was determined in this research for the performance of mechanical and thermal properties of the composites.

This chapter presents a brief account of the current state-of-the-art in the area of the tribology of fiber reinforced polymer composites. The important factors which determine the friction and wear properties of fibers from the surface modification are mentioned here. Tribological trends for fiber reinforced polymer composites, both traditional and nanocomposites, are presented using data currently available in the literature. Variation in fiber length, fiber orientation, type of treatments and physical characteristics are significantly influence the tribological properties. Finally, based on our current understanding of this field, we have speculated upon some future trends and directions in the area of polymer tribology.

A model is proposed to describe the steady-state regime of wear for a fibrous composite material in contact with a rigid counter body. The composite material is modeled by an elastic half-space with embedded elastic fibers arranged parallel to each other and distributed uniformly. The fibers hardness is assumed to be different from that of the matrix, whereas their elastic moduli are equal. Analytic relations are obtained, and analysis is performed for the characteristics of wear (worn surface shape, effective wear rate, contact pressure distribution) depending on the composite structure parameters such as fiber size and density, relative hardness of the matrix and fibers. In particular, it is shown that the effective wear rate as a function of the fiber density increases if the fibers are harder than the matrix and decreases in the opposite case. The results obtained can be used to control the wear resistance of fibrous composites by choosing appropriate microstructure parameters.

Mycelium-bound composites are promising materials for sustainable packaging, insulation, fashion, and architecture. However, moulding is the main fabrication process explored to date, strongly limiting the ability to design the complex shapes that could widen the range of applications. Extrusion is a facile and low energy-cost process that has not yet been explored for mycelium-bound composites with design freedom and structural properties. In this study, we combine cheap, easily and commonly available agricultural waste materials, bamboo microfibres, chitosan, and mycelium from Ganodermalucidum, to establish a composite mixture that is workable, extrudable and buildable. We study the impact of bamboo fibre size, chitosan concentration, pH and weight ratio of bamboo to chitosan to determine the optimum growth condition for the mycelium as well as high mechanical stiffness. The resulting materials have thus low energy costs, are sustainable and can be shaped easily. The developed composition is promising to further explore the use of mycelium-bound materials for structural applications using agricultural waste., Materials & Design, 195, ISSN:0264-1275, ISSN:1873-4197

OBJECTIVE Finite element modelling has been widely used to understand the effect of stimulation on the nerve fibres. Yet the literature on analysis of spontaneous nerve activity is much scarcer. In this study, we introduce a method based on a finite element model, to analyse spontaneous nerve activity with a typical bipolar electrode recording setup, enabling the identification of spontaneously active fibres. We applied our method to the vagus nerve, which plays a key role in refractory epilepsy. APPROACH We developed a 3D model including dynamic action potential propagation, based on the vagus nerve geometry. The impact of key recording parameters - inter-electrode distance and temperature - and uncontrolled parameters - fibre size and position in the nerve - on the ability to discriminate active fibres were quantified. A specific algorithm was implemented to detect and classify action potentials from recordings and tested on six rats in vivo vagus nerve recordings. MAIN RESULTS Fibre diameters can be discriminated if they are below 3 µm and 7 µm, respectively for inter-electrode distances of 2 mm and 4 mm. The impact of the position of the fibre inside the nerve on fibre diameter discrimination, is limited. The range of active fibres identified by modelling in the vagus nerve of rats is in agreement with ranges found at histology. SIGNIFICANCE The nerve fibre diameter, directly proportional to the action potential propagation velocity, is related to a specific physiological function. Estimating the source fibre diameter is thus essential to interpret neural recordings. Among many possible applications, the present method was developed in the context of a project to improve vagus nerve stimulation therapy for epilepsy.

International audience; Fibrin clot structure and function are major determinants of thromboembolic diseases. The study aim was to determine the impact of epicatechin (a flavonoid with cardiovascular protective effects) on fibrin clot structure and permeability.Plasma samples from 12 healthy subjects were incubated with increasing concentrations of epicatechin. Turbidity of fibrin clot was analyzed by absorbance measurement at 405 nm. The fibrin clot nanostructure was determined by scanning spectrometry (wavelength from 500 to 800 nm) and fibrin fiber size by electron microscopy. Permeability was analyzed to assess the fibrin clot functional properties.Epicatechin addition increased the maximum absorbance from 0.34 +/- 0.066 (vehicle) to 0.35 +/- 0.077 (P = 0.1), 0.35 +/- 0.072 (P < 0.05) and 0.34 +/- 0.065 (P = 0.5) for 1, 10 and 100 mu M epicatechin, respectively. Epicatechin increased the fibrin clot fiber radius (nm) from 109.2 +/- 3.2 (vehicle) to 108.9 +/- 4.3 (P = 0.9), 110.0 +/- 3.6 (P < 0.05) and 109.5 +/- 3.3 (P = 0.4), and the distance between protofibrils (nm) from 22.2 +/- 1.5 (vehicle) to 22.1 +/- 2.3 (P = 0.9), 22.6 +/- 1.8 (P < 0.05) and 22.3 +/- 1.8 (P = 0.9) for 1, 10 and 100 mu M epicatechin respectively. Electron microscopy confirmed these changes. Fibrin clot permeability, expressed as Darcy's constant (Ks, cm(2)), increased from 2.97 +/- 1.17 (vehicle) to 3.36 +/- 1.21 (P < 0.05), 3.81 +/- 1.41 (P < 0.01) and 3.38 +/- 1.33 (P = 0.9).Upon epicatechin addition, the fibrin clot structure became less dense and more permeable.

As studies examining the hypertrophic effects of resistance training (RT) at the cellular level have produced inconsistent results, we performed a systematic review and meta-analysis to investigate muscle fiber size before and after a structured RT intervention in older adults. A random-effects model was used to calculate mean effect size (ES) and 95% confidence intervals (CI). Thirty-five studies were included (age range: 59.0–88.5 yr), and 44 and 30 effects were used to estimate RT impact on myosin heavy chain (MHC) I and II fiber size. RT produced moderate-to-large increases in MHC I (ES = +0.51, 95%CI +0.31 to +0.71; P < 0.001) and II (ES = +0.81, 95%CI +0.56 to +1.05; P < 0.001) fiber size, with men and women having a similar response. Age was negatively associated with change in muscle fiber size for both fiber types (MHC I: R2 = 0.11, β = −0.33, P = 0.002; MHC II: R2 = 0.10, β = −0.32, P = 0.04), indicating a less robust hypertrophic response as age increases in older adults. Unexpectedly, a higher training intensity (defined as percentage of one-repetition maximum) was associated with a smaller increase in MHC II fiber size ( R2 = 15.09%, β = −0.39, P = 0.01). Notably, MHC II fiber subtypes (IIA, IIX, IIAX) were examined less frequently, but RT improved their size. Overall, our findings indicate that RT induces cellular hypertrophy in older adults, although the effect is attenuated with increasing age. In addition, hypertrophy of MHC II fibers was reduced with higher training intensity, which may suggest a failure of muscle fibers to hypertrophy in response to high loads in older adults.

Baked foams made with plantain flour (PF) and sugarcane fiber (SF) were characterized by calorimetric, mechanical, physicochemical and structural techniques in order to assess the results induced by different sugarcane concentrations and fiber size on the structure of baked foams. The addition of SF to the baked samples increased their hydrophobic properties. Thermal conductivity (TC) decreased when the concentration of SF was 10 g and 7.5 g in the baked foams. The density of the biodegradable baked foams (BBFs) decreased with decreasing concentrations of SF, observing an inverse behavior in water vapor permeability (WVP) and solubility properties. The mechanical properties of the baked foams were more influenced by the concentration of SF than by the size of SF, obtained from different sieves. The scanning electron microscopy cross-sectional images of the BBFs showed that the size of SF affected the size and number of the internal cells in the BBFs., Materials science, Materials chemistry, Food science, Biodegradable baked foam, Mechanical properties, Thermal conductivity, Renewable polymers, Water vapor permeability

Fiber size aspect ratio is known to impact the mechanical and reinforcement properties of natural fiber-based composites. However, the representation of fiber diameter change occurring during the e...

Reported in this paper are the effects of tip-to-collector distance, voltage, deposition time and solution concentration on the fiber size distribution and filter quality factor of electrospun cellulose acetate (CA)-based nanofibers. Nanofibrous filter samples were produced by electrospinning in a laboratory setting. The CA solutions were prepared by diluting various concentrations of CA in a 2:1 (w:w) ratio of N,N-dimethylacetamide (concentration 10–20 wt.%). The electrospinning voltages ranged from 8–12 kV, with distances from 10–15 cm and deposition times of up to 30 minutes. The produced nanofibrous filter samples were then analyzed in terms of fiber size distribution and filter quality factor using nanosized sodium chloride particles ranging from 4–240 nm in diameter. The maximum filtration efficiency measured was 99.8% for filter samples obtained with an overall deposition time of 30 minutes. The maximum filter quality factor was 0.14 Pa−1 for a CA concentration of 20 wt.% and a tip-to-collector distance of 15 cm. The average fiber diameters of the fibers were between 175 and 890 nm, and CA concentrations below 15% led to the formation of beads.

To investigate the effects of mixing polypropylene fiber of different sizes and the effect of fiber size on the impact characteristics of concrete, two sizes of polypropylene fine fiber and one siz...

Electrospun starch fiber mats have many potential applications, but an improvement in their mechanical properties is required to realize them. In the present study, wet-electrospun starch fiber mats were subjected to post-drying conditioning at controlled equilibrium relative humidity and equilibration time. The weight-normalized ultimate tensile strength of starch fiber mats increased significantly with equilibration at relative humidity >0.75 after 28 days. Morphological observation and X-ray diffraction analysis excluded significant changes in fiber size or crystallinity, and thus we concluded that conglutination brought about by the plasticizing effect of water and observed microscopically was primarily responsible for this mechanical improvement.

Introduction A method for quantifying myofiber size noninvasively would find wide use, including primary diagnosis and evaluating response to therapy. Methods Using prediction algorithms, including the least absolute shrinkage and selection operator, we applied multifrequency electrical impedance myography (EIM) to amyotrophic lateral sclerosis superoxide dismutase 1 G93A mice of different ages and assessed myofiber size histologically. Results Multifrequency EIM data provided highly accurate predictions of myofiber size, with a root mean squared error (RMSE) of only 14% in mean myofiber area (corresponding to ± 207 µm2 for a mean area of 1,488 µm2 ) and an RMSE of only 8.8% in predicting the coefficient of variation in fiber size distribution. Discussion This impedance-based approach provides predictive variables to assess myofiber size and distribution with good accuracy, particularly in diseases in which myofiber atrophy is the predominant histological feature, without the requirement for biopsy or burdensome quantification. Muscle Nerve 58: 713-717, 2018.

The aim of this study is to investigate the effects of various particle sized and different amount of plant fibers as fat mimetic for biscuit formulations instead of biscuit fat. The fibers with different particle sizes were obtained from wheat bran and used instead of fat in biscuit formulations. The texture, rheology and quality analyses of low-fat biscuit (30, 20 and 10% fat) were performed and compared with those of the full-fat control sample (40% fat). Results showed that wheat bran fiber with bigger particle size (Long Fiber, LF) were more favorable in terms of textural properties of the dough and the quality parameters of biscuits while the fibers with smaller particle size (Medium Fiber, MF and Small Fiber, SF) improved viscoelastic properties of dough similar to the control. Although the use of these fibers in the production of low-fat biscuits were suitable in terms of workability of dough increasing fiber content and/or reducing fiber size resulted in harder biscuits with lower spread ratio. This study showed that the texture of biscuits was greatly dependent on the texture of the dough. © 2018, Association of Food Scientists & Technologists (India)., Acknowledgements The authors thank the Turkish Scientific Council TUBITAK (108 M 169) for providing funding for the project.

In this study, we investigate adaptations in muscle oxidative capacity, fiber size and oxygen supply capacity in team-sport athletes after six repeated-sprint sessions in normobaric hypoxia or normoxia combined with 14 days of chronic normobaric hypoxic exposure. Lowland elite field hockey players resided at simulated altitude (≥14 h/day at 2,800–3,000 m) and performed regular training plus six repeated-sprint sessions in normobaric hypoxia (3,000 m; LHTLH; n = 6) or normoxia (0 m; LHTL; n = 6) or lived at sea level with regular training only (LLTL; n = 6). Muscle biopsies were obtained from the m. vastus lateralis before (pre), immediately after (post-1), and 3 wk after the intervention (post-2). Changes over time between groups were compared, including likelihood of the effect size (ES). Succinate dehydrogenase activity in LHTLH largely increased from pre to post-1 (~35%), likely more than LHTL and LLTL (ESs = large-very large), and remained elevated in LHTLH at post-2 (~12%) vs. LHTL (ESs = moderate-large). Fiber cross-sectional area remained fairly similar in LHTLH from pre to post-1 and post-2 but was increased at post-1 and post-2 in LHTL and LLTL (ES = moderate-large). A unique observation was that LHTLH and LHTL, but not LLTL, improved their combination of fiber size and oxidative capacity. Small-to-moderate differences in oxygen supply capacity (i.e., myoglobin and capillarization) were observed between groups. In conclusion, elite team-sport athletes substantially increased their skeletal muscle oxidative capacity, while maintaining fiber size, after only 14 days of chronic hypoxic residence combined with six repeated-sprint training sessions in hypoxia. NEW & NOTEWORTHY Our novel findings show that elite team-sport athletes were able to substantially increase the skeletal muscle oxidative capacity in type I and II fibers (+37 and +32%, respectively), while maintaining fiber size after only 14 days of chronic hypoxic residence combined with six repeated-sprint sessions in hypoxia. This increase in oxidative capacity was superior to groups performing chronic hypoxic residence with repeated sprints in normoxia and residence at sea level with regular training only.

In this study, oil palm mesocarp fiber (OPMF) was pretreated with (1) superheated steam (SHS) and (2) potassium hydroxide (KOH) to remove hemicellulose. Both SHS–OPMF and KOH–OPMF underwent delignification step to isolate the cellulose and dissolved in selected ionic liquid and its co-solvent before being electrospun to obtain microfibrillated cellulose (MFC). FE-SEM images showed that SHS–OPMF cellulose produced discontinuous MFC fiber with diameter ranging from 100 to 500 nm, of which 15.5% were in the range of 100–200 nm; while KOH–OPMF cellulose produced continuous MFC with sizes larger than 200 nm. The differences in fiber size and continuity of fiber produced were due to incomplete removal of hemicellulose from SHS–OPMF sample that inhibited fiber re-coalescence and resulted in interruption in fiber formation.

Introduction Electrical impedance can be used to estimate cellular characteristics. We sought to determine whether it could be used to approximate myofiber size using standard prediction modeling approaches. Methods Forty-four C57BL/6J wild-type immature mice of varying ages underwent electrical impedance myography (EIM) with a needle electrode array placed in the gastrocnemius. Animals were then humanely killed and muscle fixed, stained, and myofiber size quantified. Two different statistical prediction models were then applied. Results Impedance parameters showed major variation with increasing myofiber size. The prediction models based on EIM data alone were able to predict fiber size, with errors in the range of ±69.05-78.44 µm2 (16.19%-18.40% with respect to the average myofiber size). Discussion By using well-established statistical models, EIM data alone can provide a satisfactory estimate of myofiber size. Additional study of this approach for approximating myofiber size without the requirement of removing tissue for histological analysis is warranted. Muscle Nerve, 2018.

The balance of published data have largely focused on adaptations in muscle and fiber size after anterior cruciate ligament reconstruction (ACLR), failing to account for the dynamic changes in the behavior of the muscles’ contractile elements that strongly contribute to force production. To better understand the sources of quadriceps dysfunction, the purpose of our research was to determine if alterations in fascicle behavior are present after ACLR. Unilateral ACLR individuals (9 m/9f; 21 ± 3 yrs; 1.74 ± 0.12 m;71.58 ± 13.31 kg; months from surgery:38 ± 36) and healthy controls (3 m/6f; 23 ± 2 yrs; 1.67 ± 0.10 m; 63.51 ± 10.11 kg) participated. In-vivo vastus lateralis fascicle behavior was recorded using ultrasonography during three maximal isokinetic knee extensions (60°·s−1). Fascicle length, angle, and shortening velocity were calculated and analyzed from rest to peak torque. Peak knee extension torque was averaged between isokinetic trials (Nm·kg−1). Group by limb interactions were assessed using separate two-way analyses of variance and were further evaluated by comparing 95% confidence intervals where appropriate. Significant interactions were present for fascicle angle at peak torque (P = 0.01), fascicle length excursion (P = 0.05), fascicle angle excursion (P 0.05). Our data show that those with a history of ACLR have fascicles that are slower, lengthen less and operate with lower angles relative to the axis of force production. Altered fascicle behavior after ACLR may be an important underlying factor to explaining the protracted quadriceps dysfunction.

As the primary material for roadway support in underground engineering, shotcrete is of great significance to the underground construction industry. Shotcrete alone is brittle and its internal structure is prone to damage. Thus, reinforcing materials are often added to reduce the brittleness of shotcrete. Most of the studies focused on adding fiber materials to concrete the structural fractures in shotcrete. However, shotcrete internal structure fractures still happen in extreme environments. Therefore, the relationship between the mechanical properties of fiber reinforced shotcrete (FRS) and fiber fracture morphology is studied in this paper. Firstly, two types of fibers are selected, i.e., polypropylene fiber (PPF) and plastic waste fiber (PWF). Then, the mechanical properties of the FRS are tested, and the optimal fiber size of PWF reinforced shotcrete is obtained. Through optimization analysis, the mechanical property superiority of PWF reinforced shotcrete with the optimal fiber size is determined. Next, the fiber fracture in shotcrete is observed by visual and microscopic inspection, and four types of fiber fractures in shotcrete are proposed. Finally, the fiber fracture in various types of shotcrete is statistically analyzed. After correlation equation fitting, it is found that the straight-line, polynomial and exponential fitting results of mechanical properties and fiber fracture number of FRS are the most ideal. The relationship between the mechanical properties of FRS and the fiber fracture morphology is revealed. This study provides a theoretical basis for reducing the fractures of FRS structures in complex construction environments.