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The purpose of this study was to investigate the relationship between muscle fiber type-specific properties of the vastus lateralis and quadriceps muscle performance in individuals after an anterior cruciate ligament (ACL) tear. 26 subjects (22.0 ± 5.4 years) were included in this cross-sectional study, and all data were collected before ACL reconstruction. Quadriceps peak torque (QPT) and early (0-100 ms) and late (100-200 ms) rate of torque development (RTD) were obtained from maximal voluntary isometric quadriceps strength testing. Muscle fiber cross-sectional area (fCSA) and percent fiber type distribution (FT%) were evaluated through immunohistochemical analysis of a muscle biopsy. Between-limb differences in fiber characteristics were assessed using paired t-tests (with α-level 0.05). Relationships between fiber-specific properties and quadriceps muscle performance were determined using separate multiple linear regression analyses for ACL-injured and noninjured limbs. There were significant differences in fCSA between ACL-injured and noninjured limbs across all fiber types, but no differences in FT%. Type 1 fCSA, type 2a fCSA, and their interaction effect were the explanatory variables with the strongest relationship to all performance outcomes for the ACL-injured limb. The explanatory variables in the ACL-injured limb had a significant relationship to QPT and late RTD, but not early RTD. These findings suggest that QPT and late RTD are more heavily influenced by fCSA than FT% in ACL-injured limbs. This work serves as a foundation for the development of more specific rehabilitation strategies aimed at improving quadriceps muscle function before ACL reconstruction or for individuals electing nonsurgical management. [ABSTRACT FROM AUTHOR]

Copyright of Mining & Metallurgy (10057854) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT The gut microbiota contributes to skeletal muscle energy metabolism and is an indirect factor affecting meat quality. However, the role of specific gut microbes in energy metabolism and fiber size of skeletal muscle in chickens remains largely unknown. In this study, we first performed cecal microbiota transplantation from Chinese indigenous Jingyuan chickens (JY) to Arbor Acres chickens (AA), to determine the effects of microbiota on skeletal muscle fiber and energy metabolism. Then, we used metagenomics, gas chromatography, and metabolomics analysis to identify functional microbes. Finally, we validated the role of these functional microbes in regulating the fiber size via glucose metabolism in the skeletal muscle of chickens through feeding experiments. The results showed that the skeletal muscle characteristics of AA after microbiota transplantation tended to be consistent with that of JY, as the fiber diameter was significantly increased, and glucose metabolism level was significantly enhanced in the pectoralis muscle. L. plantarum, L. ingluviei, L. salivarius, and their mixture could increase the production of the microbial metabolites protoporphyrin IX and short-chain fatty acids, therefore increasing the expression levels of genes related to the oxidative fiber type (MyHC SM and MyHC FRM), mitochondrial function (Tfam and CoxVa), and glucose metabolism (PFK, PK, PDH, IDH, and SDH), thereby increasing the fiber diameter and density. These three Lactobacillus species could be promising probiotics to improve the meat quality of chicken.IMPORTANCEThis study revealed that the L. plantarum, L. ingluviei, and L. salivarius could enhance the production of protoporphyrin IX and short-chain fatty acids in the cecum of chickens, improving glucose metabolism, and finally cause the increase in fiber diameter and density of skeletal muscle. These three microbes could be potential probiotic candidates to regulate glucose metabolism in skeletal muscle to improve the meat quality of chicken in broiler production.

Duchenne muscular dystrophy (DMD) is an X-linked disease, caused by a mutant dystrophin gene, leading to muscle membrane instability, followed by muscle inflammation, infiltration of pro-inflammatory macrophages and fibrosis. The calcium-activated potassium channel type 3.1 (KCa3.1) plays key roles in controlling both macrophage phenotype and fibroblast proliferation, two critical contributors to muscle damage. In this work, we demonstrate that pharmacological blockade of the channel in the mdx mouse model during the early degenerative phase favors the acquisition of an anti-inflammatory phenotype by tissue macrophages and reduces collagen deposition in muscles, with a concomitant reduction of muscle damage. As already observed with other treatments, no improvement in muscle performance was observed in vivo. In conclusion, this work supports the idea that KCa3.1 channels play a contributing role in controlling damage-causing cells in DMD. A more complete understanding of their function could lead to the identification of novel therapeutic approaches.

This experiment aimed to investigate the impact of varying fiber lengths on the flexural strength of coconut fiber composites with epoxy resin. Coconut fiber composite panels were produced using rectangular molds. The effects of various fiber sizes, especially 2, 4, and 6 mm, respectively, were compared with fiberless and continuous fiber polymer composites on the flexural strength of Natural Fiber-reinforced Polymer Composites (NFPC). The lowest flexural strength is 10.04 MPa, was obtained for the NFPC sample with a fiber length of 2 mm, while the highest flexural strength value was 10.70 MPa with a fiber length of 6 mm. Generally, flexural strength is influenced by variations in fiber size but not significantly. The flexural modulus and flexural strength values exhibit the same trend. Fiber pullouts are visible on the fracture surface of the sample, and voids in the form of trapped gas are also apparent on the sample surface. Short fiber size is one of the causes of fiber pullout, which can reduce the flexural strength of short fiber polymers.

This paper reports a study whose object was material of the weld. The nature of changes in the microstructure of the weld material, which are caused by changes in the supplied energy, alloying elements and heat removal from the melt area, was investigated. Welding was performed with an electron beam at Uacc=60 kV, Ieb=90 mA, with an elliptical sweep of 3×4 mm. The speed of electron beam movement veb was varied from 7 to 15 mm·s-1. The temperature of the experimental welded samples T0 was varied from 300 K to 673 K. Ti-TiB alloy (a microcomposite alloy with reinforcing TiB fibers) was welded with Ti-TiB alloys, T110, and with niobium. One of the tasks of welding this alloy was to preserve and optimize the structure of this type in the weld. Grinding of boride fibers, loss of their initial orientation, and formation of a dendritic or cellular microstructure was observed in the weld. Using the methods of raster electron microscopy and micro-X-ray spectral analysis, the microstructure of the weld material was investigated and the dimensional characteristics of TiB fibers under different welding conditions were determined. The analysis of changes in the microstructure of the weld material, the average length ᶏ and the thickness ȩ of the boride fibers in the material of the joints made at different velocities of electron beam movement and initial temperatures T0 was carried out. It was established that the growth of the ratio ȩ/ᶏ from 0.04–0.07 to 0.1–0.27 is accompanied by significant changes in the micro-structure and the mechanism of formation of eutectic phases. It is shown that the process that determines the formation of the micro-structure of the weld material was the eutectic breakdown with the determining influence of the temperature gradient, crystallization rate, supercooling, concentration inhomogeneities, and alloying impurities. [ABSTRACT FROM AUTHOR]

Bamboo mesoparticles were used as a viable alternative reinforcement in matrix polymers to produce eco-friendly products, and the alternative mesoparticles were used as reinforcement for cheaper processing methods and comparable mechanical properties as nanoparticle. The main factors that influence the mechanical behavior of natural composites are fiber size, fiber loading, and chemical treatment. This study optimized the blending parameters of bamboo mesoparticle/polyamide 6 composites through response surface methodology based on Box–Behnken design. The predicted strength values for these composites as a function of independent variables were obtained from the analysis of variance statistical approach. The analysis of the results showed that fiber size, fiber loading, and alkali concentration variables significantly in quadratic model terms. This model was used to determine the maximum strength, and it was closely in agreement with the experimental finding with the value of R2 = 0.9385. The optimum conditions for tensile strength were identified as fiber size 1 µm, NaOH of 2 wt.%, and fiber loading of 18 wt.%. The optimum conditions for flexural strength were identified as NaOH of 2 wt.%, particle loading of 13 wt.%, and particle size of 0.46 µm. [ABSTRACT FROM AUTHOR]

This study investigates how sonication amplitude and time affect 2 wt% cationic nanofibrils (CCNF) and microfibrils (CCMF) dispersions, focusing on mechanical properties and flow behavior. Sonication reduces fiber diameter and increases the concentration of substituent groups available for hydrogen bonding. This effect becomes significant when diameters fall below 100 nm, leading to enhanced storage and loss moduli. CCNF achieves a maximum shear modulus of 600 Pa, whereas CCMF fibers do not undergo similar size reductions. CCNF's viscosity and critical stress follow a square root relationship with sonication amplitude, due to minimal fiber size reduction at high sonication levels (smaller than 20 nm), unlike CCMF (diameter reduction up to 50 nm), which exhibits a linear increase due to more pronounced fiber fragmentation. At high sonication levels, CCNF shows an exponential rise in critical stress (up to 800 Pa), suggesting tiny fibers infiltrate the hydrogel network, thereby improving its integrity and resistance to shear stresses. By integrating theoretical models with experimental findings, this work presents a unified view of sonication's essential role in fine-tuning the mechanical and flow properties of cellulose-based materials. This research enhances understanding of cellulose dispersion behavior under sonication and provides a foundation for designing optimized cellulose-based materials. • Sonication decreases fiber size and affects distribution and surface functionality. • Sonication enhances hydrogen bonding and strengthens the hydrogel network. • Sonication impact differs between CCNF and CCMF dispersions. • Model prediction of cross-link density in dispersions upon sonication • Fine-tuning of cellulose-based materials for tailored material design [ABSTRACT FROM AUTHOR]

Wooden breast myopathy (WB) strongly affects the poultry industry mainly in terms of consumers rejection and economical loses, due to morphological changes in broiler muscle tissue and consequently low meat quality. The aim of this study is to evaluate the histomorphometry of muscle fibers of breast fillets of broilers with severity levels of WB myopathy. The histological evaluation considered 30 samples of the pectoralis major muscle and the level of WB myopathy (ten normal fillets, ten moderate fillets, and ten severe fillets). Fillets with a severe level of WB present low average fiber number, high average fiber diameter, low percentage of fibers with diameter of less than 20 µm, low percentage of fibers with diameter between 20 and 40 µm, and high percentage of fibers with diameter between 40 and 70 µm. Fiber cross-sectional area is greater in fillets affected by moderate and severe WB. Thus, fillets with a severe level of WB damage the muscle fiber structure and contribute more severely to the degenerative processes of breast meat.

Background Context: Chronic spinal pain is one the most common musculoskeletal disorders. Previous studies have observed microscopic structural changes in the spinal extensor muscles in people with chronic spinal pain. This systematic review synthesizes and analyzes all the existing evidence of muscle microscopic changes in people with chronic spinal pain.Purpose: To assess the microscopy of spinal extensor muscles including the fiber type composition, the area occupied by fiber types, fiber size/cross sectional area (CSA), and narrow diameter (ND) in people with and without chronic spinal pain. Further, to compare these outcome measures across different regions of the spine in people with chronic neck, thoracic and low back pain.Study Design: Systematic review with meta-analysis.Methods: MEDLINE (Ovid Interface), Embase, PubMed, CINAHL Plus, and Web of Science were searched from inception to October 2020. Key journals, conference proceedings, grey literature and hand searching of reference lists from eligible studies were also searched. Two independent reviewers were involved in the selection process. Only studies examining the muscle microscopy of the spinal extensor muscles (erector spinae [ES] and/or multifidus [MF]) between people with and without chronic spinal pain were selected. The risk of bias from the studies was assessed using modified Newcastle Ottawa Scale and the level of evidence was established using the GRADE approach. Data were synthesized based on homogeneity on the methodology and outcome measures of the studies for ES and MF muscles and only four studies were eligible for analysis.Results: All the five studies included were related to chronic low back pain (CLBP). Meta-analysis (inverse variance method for random effect to calculate mean difference and 95% CI) was performed for the ES fiber type composition by numbers for both type I and type II fibers (I2=43% and 0% respectively indicating homogeneity of studies) and showed no difference between the people with and without CLBP with an overall effect estimate Z= 1.49 (p=.14) and Z=1.06 (p=.29) respectively. Meta-analysis was performed for ES fiber CSA for both type I and type II fibers (I2=0 for both) and showed no difference between people with and without CLBP with an overall effect estimate Z=0.08 (p=.43) and Z=0.75 (p=.45) respectively. Analysis was not performed for ES area occupied by fiber types and ND due to heterogeneity of studies and lack of evidence respectively. Similarly, meta-analysis was not performed for MF fiber type composition by numbers due to heterogeneity of studies. MF analysis for area occupied by fiber type, fiber CSA and ND did not yield sufficient evidence.Conclusions: For the ES muscle, there was no difference in fiber type composition and fiber CSA between people with and without CLBP and no conclusions could be drawn for ND for the ES. For the MF, no conclusions could be drawn for any of the muscle microscopy outcome measures. Overall, the quality of evidence is very low and there is very low evidence that there are no differences in microscopic muscle features between people with and without CLBP. [ABSTRACT FROM AUTHOR]

Background: Tissue engineering of the annulus fibrosus (AF) shows promise as a treatment for patients with degenerative disc disease (DDD). However, it remains challenging due to the intrinsic heterogeneity of AF tissue. Fabrication of scaffolds recapitulating the specific cellular, componential, and microstructural features of AF, therefore, is critical to successful AF tissue regeneration. Methods: Poly-L-lactic acid (PLLA) fibrous scaffolds with various fiber diameters and orientation were prepared to mimic the microstructural characteristics of AF tissue using electrospinning technique. AF-derived stem cells (AFSCs) were cultured on the PLLA fibrous scaffolds for 7 days. Results: The morphology of AFSCs significantly varied when cultured on the scaffolds with various fiber diameters and orientation. AFSCs were nearly round on scaffolds with small fibers. However, they became spindle-shaped on scaffolds with large fibers. Meanwhile, upregulated expression of collagen-I gene happened in cells cultured on scaffolds with large fibers, while enhanced expression of collagen-II and aggrecan genes was seen on scaffolds with small fibers. The production of related proteins also showed similar trends. Further, culturing AFSCs on a heterogeneous scaffold by overlaying membranes with different fiber sizes led to the formation of a hierarchical structure approximating native AF tissue. Conclusion: Findings from this study demonstrate that fibrous scaffolds with different fiber sizes effectively promoted the differentiation of AFSCs into specific cells similar to the types of cells at various AF zones. It also provides a valuable reference for regulation of cell differentiation and fabrication of engineered tissues with complex hierarchical structures using the physical cues of scaffolds. The translational potential of this article: Effective AF repair is an essential need for treating degenerative disc disease. Tissue engineering is a promising approach to achieving tissue regeneration and restoring normal functions of tissues. By mimicking the key structural features of native AF tissue, including fiber size and alignment, this study deciphered the effect of scaffold materials on the cell differentiation and extracellular matrix deposition, which provides a solid basis for designing new strategies toward more effective AF repair and regeneration.

The following manuscript presents a comprehensive investigation regarding the influence of electrospinning parameters on fiber quality and mechanical properties of nanofibrous poly(amino acid) meshes. At first, we examine parameters including: solvent options, polymer concentrations, collector speed and distance, voltage, needle sizes and flow rates to prepare fibrous scaffolds based on polysuccinimide. The main objective was to attempt and decrease the fiber diameter as much as possible while not reducing the fiber quality. After that mechanical properties of the meshes were investigated, we demonstrate two possible methods to reinforce them: mechanically induced alignment of the fibers and multilayer compression. Characterization methods include a solubility study, viscosity and conductivity measurements, ATR‐FTIR spectroscopy, scanning electron microscopy, and mechanical uniaxial test. Fiber size was successfully reduced from 615 to 280 nm without any quality aberrations. Mechanical performance not only improved almost three‐fold, but was also enhanced in two directions due to the multilayer composition. With these optimizations, the PSI mesh now possess favorable features for biomedical application according to the relevant literature. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) is an X-linked disease, caused by a mutant dystrophin gene, leading to muscle membrane instability, followed by muscle inflammation, infiltration of pro-inflammatory macrophages and fibrosis. The calcium-activated potassium channel type 3.1 (KCa3.1) plays key roles in controlling both macrophage phenotype and fibroblast proliferation, two critical contributors to muscle damage. In this work, we demonstrate that pharmacological blockade of the channel in the mdx mouse model during the early degenerative phase favors the acquisition of an anti-inflammatory phenotype by tissue macrophages and reduces collagen deposition in muscles, with a concomitant reduction of muscle damage. As already observed with other treatments, no improvement in muscle performance was observed in vivo. In conclusion, this work supports the idea that KCa3.1 channels play a contributing role in controlling damage-causing cells in DMD. A more complete understanding of their function could lead to the identification of novel therapeutic approaches. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the ablation efficiency of super-pulse thulium fiber laser (SPTFL) with different laser settings and fiber usage. Materials and Methods: SPTFL machine was attached with different fibers. Artificial stones were fixed in water, whereas laser fiber was driven on a platform for ablation. Pulse energy, frequency, fiber-moving speed, fiber-to-stone distance, and fiber size were adjusted in each trial. The cross-sectional area of craters on the lateral stone surface was measured for comparison of ablation rate, combined with fiber-moving speed. Results: There was a trend that the ablation rate increased as pulse energy or frequency increased. When pulse energy was set as 0.2 J and frequency was increased from 50 to 150 Hz, the cross-sectional area of the crater was enlarged from 0.21 to 0.37 mm2 (p < 0.05); when the frequency was set as 100 Hz and pulse energy was increased from 0.1 to 0.3 J, the crater was enlarged from 0.10 to 0.45 mm2 (p < 0.05). Furthermore, energy demonstrated greater impact on ablation rate and the crater was enlarged from 0.20 mm2 in the 0.1 J × 300 Hz group to 0.44 mm2 in the 0.3 J × 100 Hz group (p < 0.05). Then fiber was set at different moving speeds with the same laser setting; the ablation rate of 3 mm/second group was 3.64 times higher than 0.5 mm/second group (p < 0.05). Ablation diminished as fiber-to-stone distance grew. A 200 μm fiber produced thinner and deeper fissure than 272 and 550 μm fibers, and the ablation rate was the highest for the 200 μm fiber. Conclusion: Pulse energy is a more important factor in influencing ablation efficiency compared with frequency. Closer fiber-to-stone distance, faster fiber movement, and smaller fiber size increase ablation efficiency. [ABSTRACT FROM AUTHOR]

• Chemical composition of 88 mineral wool samples is reported. • Glass wool composition is similar to soda-lime silicate glass. • Stone wools have composition similar to basalt, but variation is observed. • Cr, Ba, Ni, Cu, Zn, and Pb are present in mineral wools, but in low concentrations. • Organic resin within mineral wools may cause NH 3 emissions during their processing. Despite mineral wool waste is only a small fraction of total construction and demolition waste (CDW) by mass, it requires large transportation and landfilling capacities due to its low bulk density, and its utilization remains low compared to other CDW types. It is essential to understand the physical and chemical properties of this waste fraction in order to utilize it, e.g. as fiber reinforcement in composites or as supplementary cementitious material. Here, we provide a chemical and physical characterization of 15 glass wool and 12 stone wool samples of different ages collected from various locations across Europe. In addition, the chemical compositions of 61 glass and stone wool samples obtained from the literature are presented. Glass wool samples show little variation in their chemical composition, which resembles the composition of typical soda-lime silicate glass. Stone wool presents a composition similar to basaltic glass but with variability between samples in terms of calcium, magnesium, and iron content. Potentially toxic elements, such as Cr, Ba, and Ni, are present in mineral wools, but in low concentrations (<0.2%). Both wool types contain organic resin, which may decompose into smaller molecular fragments and ammonia upon heating or contact with alkaline solution. Mineral wool wastes have relatively similar length and width distributions, despite the age and type of the mineral wool. Overall, both mineral wool waste types have homogenous chemical and physical properties as compared to many other mineral wastes which makes their utilization as a secondary raw material promising. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The repair, remodeling, and regeneration of myofibers are dependent on satellite cells (SCs), although, the distribution of SCs in different fiber types of human muscle remains inconclusive. There is also a paucity of research comparing muscle fiber characteristics in a sex‐specific manner. Therefore, the aim of this study was to investigate fiber type‐specific SC content in men and women. Muscle biopsies from vastus lateralis were collected from 64 young (mean age 27 ± 5), moderately trained men (n = 34) and women (n = 30). SCs were identified by Pax7‐staining together with immunofluorescent analyses of fiber type composition, fiber size, and myonuclei content. In a mixed population, comparable number of SCs was associated to type I and type II fibers (0.07 ± 0.02 vs 0.07 ± 0.02 SCs per fiber, respectively). However, unlike men, women displayed a fiber type‐specific distribution, with SC content being lower in type II than type I fibers (P =.041). Sex‐based differences were found specifically for type II fibers, where women displayed lower SC content compared to men (P <.001). In addition, positive correlations (r‐values between 0.36‐0.56) were found between SC content and type I and type II fiber size in men (P =.03 and P <.01, respectively), whereas similar relationships could not be detected in women. Sex‐based differences were also noted for fiber type composition and fiber size, but not for myonuclei content. We hereby provide evidence for sex‐based differences present at the myocellular level, which may have important implications when studying exercise‐ and training‐induced myogenic responses in skeletal muscle. [ABSTRACT FROM AUTHOR]

Sulforaphane (SFN) has shown diverse effects on human health and diseases. SFN was administered daily to C57BL/6J mice at doses of 1 mg/kg (SFN1) and 3 mg/kg (SFN3) for 8 weeks. Both doses of SFN accelerated body weight increment. The cross-sectional area and diameter of Longissimus dorsi (LD) muscle fibers were enlarged in SFN3 group. Triglyceride (TG) and total cholesterol (TC) levels in LD muscle were decreased in SFN groups. RNA sequencing results revealed that 2455 and 2318 differentially expressed genes (DEGs) were found in SFN1 and SFN3 groups, respectively. Based on GO enrichment analysis, 754 and 911 enriched GO terms in the SFN1 and SFN3 groups, respectively. KEGG enrichment analysis shown that one KEGG pathway was enriched in the SFN1 group, while six KEGG pathways were enriched in the SFN3 group. The expressions of nine selected DEGs validated with qRT-PCR were in line with the RNA sequencing data. Furthermore, SFN treatment influenced lipid and protein metabolism related pathways including AMPK signaling, fatty acid metabolism signaling, cholesterol metabolism signalling, PPAR signaling, peroxisome signaling, TGFβ signaling, and mTOR signaling. In summary, SFN elevated muscle fibers size and reduced TG and TC content of in LD muscle by modulating protein and lipid metabolism-related signaling pathways., (© 2024 The Author(s).)

Gas permeability and structure of fiberboard mats are essential properties because of their impact on mat internal gas pressure, moisture content and temperature evolution during the hot-pressing process. The objectives of this work were to determine the effect of fiber size and mat density on the intrinsic gas permeability of the mat. For the study of these mat properties, panels with a homogeneous density profile through the thickness were manufactured at five density levels (200, 400, 600, 800 and 1000 kg m−3) for three different fiber sizes. Fiber refining was performed in a disk refiner at three plate spacings. Gas permeability was measured with an in-house built apparatus. The results showed that the fiber sizes studied had no significant effect on the intrinsic permeability. This was likely due to a more significant impact of the internal porous structure of the mat compared to fiber size. Besides, the intrinsic permeability decreased significantly when the panel density increased from 198 to 810 kg m−3. This suggests that the decrease of the intrinsic gas permeability during the last seconds of press closure plays an essential role in the bulk moisture mass transfer through the fiberboard mat. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research was conducted to determine the interaction of NDF level and fiber particle size on the performance of production, digestibility of dry matter, crude fiber and fiber fraction, digestive tract, microbial profiles, volatile fatty acids (VFA), and total organic acid of rabbits during the fattening period. The experiment utilized 144 New Zealand white (NZW) crossbred rabbits aged 28 days. The experimental design was a completely randomized 3 x 3 factorial pattern, with 3 levels of neutral detergent fiber (NDF) (F1= 33.60%, F2= 36.10%, and F3= 41.43%) and 3 sizes of fiber particles (P1= 1 mm, P2= 2 mm, and P3= 3 mm). Each treatment had 4 replications, and each replication had 4 animals. The combination treatment showed changes in feed intake with an average of 5.25 kg/head. The F2 treatment showed the best results in body weight gain (BWG) and feed conversion ratio (FCR) with an average of 1.80 kg/head and 3.09, respectively. The F1 level showed the highest average of pathogenic bacteria (E. coli) population at 3.37 x 109 cfu/mL which inversely proportional to the average level of butyric acid percentage and total organic acids which were 12.92% and 386.23 mmol/L in rabbits during the post-weaning period. The conclusion of this study was that the inclusion of NDF and a balanced size of fiber feed in feed could lead to optimization of the fiber digestibility, digestive tract, total organic acid production, and butyric acid concentration which could suppress the growth of E. coli and improve the performance of rabbits during the fattening period.

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.

Electrospun polymeric meshes have revolutionized the evolving tissue engineering field for their extracellular matrix mimicry. However, besides the fibrous architecture, cell-material interactions are also critically and synergistically influenced by specific surface chemical and topographical features, such as fiber size and fiber orientation. To examine these effects in detail, random polycaprolactone (PCL) fibers with average diameters of 232, 500 and 1272 nm and highly aligned fibers with diameters of 225, 482 and 1173 nm are electrospun in this work. Surface biofunctionalization is then achieved by plasma-treating the fibers using argon at medium pressure. Results reveal a significantly enhanced wettability on plasma-treated fibers due to the incorporation of oxygen-containing functionalities on their surface. A treatment time of 15 s is shown to preserve the scale and morphology of all fiber conditions. However, an extended plasma exposure starts damaging the fibers with a growing risk of drastic alterations on thicker and random fibers compared to thinner and aligned fibers. These diverse responses stem from the distinct molecular chain arrangement and crystallinity of different fiber sizes and orientations. The fibers bioresponsive properties are also profoundly investigated in this study by seeding and evaluating adipose-derived stem cells (ADSCs) performance. Plasma treatment strikingly enhances the cell metabolic activity, adhesion, proliferation and cytoplasmic remodeling on all samples. Cells adhere multi-directionally on random fibers with a gradual change from dilated and more circular to a stretched out and more elongated shape on increasing diameters. In contrast, ADSCs overextend in a bipolar and aligned fashion on aligned fibers with a tendency to attach on fewer fibers with increasing fiber diameter. A critical distinction is the cell infiltration in-between the pores of the thickest fibers. Overall, plasma-treated fibers are very promising substrates for multiple tissue engineering applications. Since the desired ADSCs behavior observed on distinct fiber size and orientation strongly depends on a specific end-application, this work constitutes a picture-perfect reference paving the way towards the optimization of the previous generation of scaffolds. Unlabelled Image • Random fibers of 232–1272 nm and highly aligned fibers of 225–1173 nm are studied. • Argon DBD plasma enhances fiber wettability by incorporating surface oxygen groups. • Plasma treatment greatly improves cell behavior on all fiber sizes and orientations. • Cells grow multi-directionally on random fibers and bi-directionally on aligned fibers. • Cells gradually change from circular to elongated shape on increasing fiber sizes. [ABSTRACT FROM AUTHOR]

This research was conducted to determine the interaction of NDF level and fiber particle size on the performance of production, digestibility of dry matter, crude fiber and fiber fraction, digestive tract, microbial profiles, volatile fatty acids (VFA), and total organic acid of rabbits during the fattening period. The experiment utilized 144 New Zealand white (NZW) crossbred rabbits aged 28 days. The experimental design was a completely randomized 3 x 3 factorial pattern, with 3 levels of neutral detergent fiber (NDF) (F1= 33.60%, F2= 36.10%, and F3= 41.43%) and 3 sizes of fiber particles (P1= 1 mm, P2= 2 mm, and P3= 3 mm). Each treatment had 4 replications, and each replication had 4 animals. The combination treatment showed changes in feed intake with an average of 5.25 kg/head. The F2 treatment showed the best results in body weight gain (BWG) and feed conversion ratio (FCR) with an average of 1.80 kg/head and 3.09, respectively. The F1 level showed the highest average of pathogenic bacteria (E. coli) population at 3.37 x 109 cfu/mL which inversely proportional to the average level of butyric acid percentage and total organic acids which were 12.92% and 386.23 mmol/L in rabbits during the post-weaning period. The conclusion of this study was that the inclusion of NDF and a balanced size of fiber feed in feed could lead to optimization of the fiber digestibility, digestive tract, total organic acid production, and butyric acid concentration which could suppress the growth of E. coli and improve the performance of rabbits during the fattening period. [ABSTRACT FROM AUTHOR]

The total number of myelinated fibers in corpus callosum (CC) in Alzheimer's disease is poorly described. Using a two-dimensional fractionator principle we estimated the total number of fibers in ten females patients with Alzheimer's disease (AD) (mean age 82.8 years) and 12 female control subjects (mean age 80.6 years) and found the mean number of myelinated fibers to be significantly 30% higher in the control group (90.0 × 10 6 ; coefficient of variation = SD/mean = 27%) than in the AD group (69.3 × 10 6 ; coefficient of variation = 20%) ( p = 0.028). A significant loss of fibers (≥2.2 μm in diameter) was found in the anterior part of the CC in AD patients compared to control subjects ( p = 0.045). For both groups, we found a positive correlation between the total number of myelinated fibers and CC cross-sectional area (AD, r = 0.81; control subjects, r = 0.73). There was a negative correlation in both groups between age and total number of myelinated fibers (AD, r = −0.81; controls subjects, r = −0.59). These results implicate a loss of intrahemispheric connections in the pathophysiology of AD. [ABSTRACT FROM AUTHOR]

Chrysotile asbestos fibers were added to roofing products, including roof cement, for several decades. The fibers were described as “encapsulated” and therefore incapable of being released, an assertion that is disproved by the study reported herein. Three test panels of roof cement from the original container were exposed to ambient weathering in 2015 and 2016. Two panels were then sampled using the ASTM D5755 microvacuum method. Sampling revealed a light brown sub-layer under the dark brown surface layer, both of which crumbled and became friable during sampling. Analysis of the microvacuum samples with transmission electron microscopy showed that the material on the 2 panels contained 4,432,000 and 3,320,000 asbestos structures per cm² with nearly all of the structures consisting of fibers less than 5 µm long. Energy dispersive spectrometry determined that none of the fibers reported were coated with asphalt. The presence of free fibers was confirmed by direct examination of the surfaces of the panels and of dust released from handling the panels via scanning electron microscopy. This study confirmed the releasability of uncoated asbestos fibers from dried roof cement that was indicated in 2 previous studies published in 2007 and 2010. These results suggest that the finding of the Fifth Circuit Court in 1997 that uncoated airborne asbestos fibers cannot be released from roof cement, and therefore do not present a potential exposure by inhalation, was erroneous in retrospect. The exemption of roof cement from regulation under the Occupational Safety and Health Administration Construction Industry Standard for asbestos by the Court should not be relied on by employers of workers who remove weathered asbestos-containing roof cement, and precautions should be taken against exposure to airborne asbestos fibers during this work. [ABSTRACT FROM AUTHOR]

Thermoplastic mengkuang composites are an alternative material to solve environmental pollution issues associated with synthetic polymers. Mengkuang, or Pandanus atrocarpus, raw fiber was cut, dried, ground, and sieved to the required size. The fiber was filled into the matrix of natural rubber (NR) and high-density polyethylene (HDPE) by melt blending via internal mixer. The blend of HDPE/NR at 60/40 ratio with fiber sizes of 125 µm, 250 µm, and 500 µm were prepared at fiber contents of 10%, 20%, and 30%. The effects of fiber size and fiber content on the thermoplastic composite were investigated using tensile test, impact test, water absorption, and field emission scanning electron microscopy (FESEM). The maximum tensile strength and tensile modulus were obtained at 20% fiber content of 250 µm fiber size. Impact strength gradually decreased with the increased percentage of fiber content at fiber size, 125 µm and 250 µm. The highest tensile strain at break and lowest water absorption was observed at 10% fiber content for all sizes being studied. The effects of fiber size on water absorption, and percentage of fiber content on impact strength and tensile strain at break were statistically significant (p < 0.05). [ABSTRACT FROM AUTHOR]

Detailed investigation is made of the thermoluminescence (TL) response of various sizes of optical fiber, fibers being developed with either a fixed core-to-cladding ratio or various core-to-cladding ratios. Two Ge-doped optical fiber preforms have been used to reconfirm the experimental findings. For further clarification, a pure silica rod has also been used to fabricate different diameter rods. Experimental investigations show the main TL signal to be generated from the fiber core within which the Ge is doped, the fiber cladding producing insignificant TL signal. Prior to normalization, the results show that in doubling the fiber diameter the TL signal quadruples. Conversely, subsequent to normalizing the different sizes of optical fiber to their mass or fiber cross sectional area, the smaller diameter fibers show slightly greater sensitivity compared to the larger diameter fibers. Relating to the fiber drawing-down process, this is due primarily to the greater shearing effect that the smaller fibers experience compared to the larger fibers within the fiber preform neck-down region. [ABSTRACT FROM AUTHOR]

This work investigated the effect of maple fiber size and content on the auto-hybridization of linear low density polyethylene (LLDPE) composites. The samples were compounded by twin-screw extrusion and molded by compression molding. Different fiber loadings (5 to 20% wt.), fiber sizes (0-425 microns) and size ratios (30/70, 50/50, 70/30 of short, medium, and long fibers) were used to prepare the auto-hybrid composites with 3% of coupling agent (maleated polyethylene). Micrographs and impact strength results showed that the fracture in auto-hybrid composites is mostly dependent on the longer fibers. At 10% wt. the optimum ratio was 30/70 of shorter/longer fibers, which improved tensile strength (20%), tensile modulus (20%), and impact strength (13%) compared with composites with a single fiber size. But at 20% wt., tensile modulus increased by 30% and torsion modulus by 40% above the rule of hybrid mixtures (RoHM) at a 70/30 ratio of shorter/longer fibers. [ABSTRACT FROM AUTHOR]

Fiber thermomechanical refining is a critical step for the manufacturing of medium density fiberboard (MDF). To increase productivity and improve fiber quality with a reduction in energy consumption during refining, it is essential to determine appropriate refining conditions, such as the chips retention time (accumulated chip height, CH) in the pre-heater, feeding screw revolution speed (SR) in the chip feeding pipe, and the opening ratio of the discharge valve (OV) in the discharge pipe. Using multiple regression analysis, relationships between the response variables (the total fibers, the specific energy consumption obtained by the motor power consumption/the total amount of dry fibers, and the percentage of qualified fibers) and the predictor variables (OV, CH, and SR) were modeled. Specific energy consumption decreased with an increase in CH. When more chips were stored in the pre-heater, the chips were softened by the extended steam-treatment time, reducing the energy consumption. There were negative relationships between the percentage of qualified fibers and the predictor variables (OV and SR). It was reasoned that a greater proportion of coarse fibre was produced when the discharge valve opening ratio or the feeding screw speed increased. This resulted in a reduction in the percentage of qualified fibers. Due to the large sample size (1667 measurements for each variable) in this study, the resulting regression equations can be applied to estimate the productivity, energy consumption, and fiber quality during refining in an MDF mill.