Fiber Bundle Thickness Research Articles

Enhancing the performance of cut-resistant gloves with glass fiber/UV PUA resin composite threads: A study on mechanical properties and durability

Due to the brittleness of glass fibers, cut-resistant fabrics knitted from glass fibers tend to develop broken fiber ends on the surface during use. This can cause itching, redness, or even allergic reactions on the wearer’s skin, severely affecting wearing comfort. Glass fiber bundles (GF) and glass/steel fiber bundles (GS) were impregnated with ultraviolet-cured polyurethane acrylate (UV PUA) resins at varying hydroxyethyl methacrylate (HEMA) concentrations, resulting in glass fiber/UV PUA composite threads (GUCT) and glass/stainless steel fiber bundles/UV PUA composite (GSCT). The impact of different concentrations of HEMA on the composite threads was examined in the study. Its main objectives were to evaluate the mechanical properties of the PUA resin, the tensile strength of the composite threads, and the washability, wear resistance, and cut resistance of the knitted composite fabrics. The research results show that the infiltration of PUA resin improved the tensile strength of GF and GS (increased by 64.35% and 64.84%, respectively), thus reducing the likelihood of glass fibers breaking due to excessive tensile stress. The cutting load of GF fabric increased by 24.51%, whereas GS fabric decreased by 18.25%. In addition, the wear resistance of both composite thread fabrics decreased due to changes in fiber bundle thickness caused by PUA resin impregnation, which affected the outer yarn density. The washability of the fabric indicates that this process significantly reduced the number of broken ends in glass fibers, improving the comfort of GF and GS fabrics.

Relationship between first tarsometatarsal ligament morphology and its continuity with the fibularis longus and first tarsometatarsal joint degeneration.

This study explored the relationship between the morphological characteristics of the first tarsometatarsal ligaments and fibularis longus (FL) and the severity of articular cartilage degeneration in the first tarsometatarsal joint. Sixty legs from 30 cadavers were examined. The plantar, dorsal, and medial first tarsometatarsal ligaments were classified by fiber bundle number, and their morphological characteristics (fiber bundle length, width, thickness) were measured. The FL was categorized by its continuity with the plantar first tarsometatarsal ligament (PTML): Type A, connection with the PTML only on the first metatarsal; Type B, connection along the entire PTML; and Type C, no connection with the PTML. The severity of articular cartilage degeneration was assessed in four stages. No significant differences in cartilage degeneration among ligament types were found. Negative correlations were observed between the fiber bundle width and thickness of the PTML and the severity of cartilage degeneration. FL was classified as Type A in 68%, Type B in 27%, and Type C in 5% of feet. The fiber bundle thickness of the PTML in Type B was greater than in other types. Our findings suggest that smaller fiber bundle width and thickness in the PTML may be associated with severe cartilage degeneration. The FL had continuity with the PTML in 95% of feet and could enhance the mechanical strength of the PTML in Type B feet.

Морфологическое обоснование применения альтернативного аллотрансплантата для офтальмохирургии

Purpose. Morphological assessment of fibrearchtechtonics of dispersed allografts made of cadaveric fascia lata. Material and methods. The morphological study of cadaveric fascia lata, made of its whole spirits-preserved and crushed grafts (10 samples each) was carried out. Light microscopy of collagen fibers (thickness of fiber bundles and gaps between them) in glycosaminoglycans (Hale's hystochemical reaction) was performed. Results. Studies of fascia lata samples which underwent technological processing showed that the tissue structure and its glycosaminoglycans are preserved; there was only a slight defibration of collagen fiber bundles. At the same time cellullar elements undergo complete destruction which reduces the immugenicity of allograft. It has been established that, in general, dispersed allografts have the same properties as native and preserved ones. Conclusion. Physicochemical processing of donor tissues, its crushing, fractioning and radiant sterilization allow to keep fibrearchtechtonics of fascia lata when making dispersed allografts, what is important for regenerative processes in ophthalmic surgery. Key words: morphological study, fibrearchtechtonics, fascia lata, structure, grafts, injectable biomaterials

Morphological characteristics of the plantar calcaneocuboid ligaments

BackgroundThe aim of this study was to clarify the differences in morphological features between the long plantar ligament (LPL) and the short plantar ligament (SPL).MethodsThis investigation examined 50 legs from 25 Japanese cadavers. The LPL and SPL of each leg were classified into one of three types based on the shape and number of fiber bundles. Then, fiber bundle length, fiber bundle width, and fiber bundle thickness were measured.ResultsThe LPL was rectangular in shape (Type I) in 12%, hourglass shape (Type II) in 62%, and triangular in shape (Type III) in 26%. The SPL was a single fiber bundle (Type I-a) in 26%, a surface fiber bundle and a deep fiber bundle (Type I-b) in 60%, and a surface fiber bundle (medial and lateral) and a deep fiber bundle (Type II) in 14%. Regarding the morphological characteristics, there were no significant differences among the types in the LPL, but there were differences between types and between surface and deep fiber bundles in the SPL.ConclusionsFor the LPL, the hourglass shape is the most common type. However, there appeared to be no functional difference due to the difference in the shape of the LPL, since there were no significant differences among the types in the LPL. For the SPL, there were types of single, double and triple fiber bundles; there may be functional differences based on the number of fiber bundles and between superficial and deep fibers.

Evaluation of Papillomacular Nerve Fiber Bundle Thickness Change after Vitrectomy Surgery for Idiopathic Epiretinal Membrane

Evaluation of Papillomacular Nerve Fiber Bundle Thickness Change after Vitrectomy Surgery for Idiopathic Epiretinal Membrane

Morphological characteristics of the Lisfranc ligament

BackgroundThis study aimed to clarify the morphological characteristics of the Lisfranc ligament and the cuneiform 1-metatarsal 2&3 plantar ligament (CMPL).MethodsForty legs from 20 cadavers were examined. Classification proceeded according to the number of fiber bundles in the Lisfranc ligament and the CMPL. Morphological features measured were fiber bundle length, width, thickness, and angle.ResultsIn Type I-a, the Lisfranc ligament and the CMPL were a single fiber bundle; in Type I-b, the Lisfranc ligament was a single fiber bundle, and the CMPL was two fiber bundles; in Type II-a, the Lisfranc ligament was a two fiber bundle, and the CMPL was a single fiber bundle; in Type II-b, the Lisfranc ligament and the CMPL were two fiber bundles; in Type III-a, the Lisfranc ligament was three fiber bundles, and the CMPL was a single fiber bundle; in Type III-b, the Lisfranc ligament was three fiber bundles, and the CMPL was two fiber bundles; in Type IV, the Lisfranc ligament and the CMPL could not be separated. Type I-a was seen in 37.5%, Type I-b in 10%, Type II-a in 30%, Type II-b in 7.5%, Type III-a in 7.5%, Type III-b in 2.5%, and Type IV in 5%. The Lisfranc ligament was significantly larger than the CMPL in total fiber bundle width, total fiber bundle thickness, and total fiber bundle angle.ConclusionThe Lisfranc ligament had up to 3 fiber bundles and the CMPL had one or two fiber bundles; classifications were four types and two subgroups.

Evaluation of Papillomacular Nerve Fiber Bundle Thickness in Glaucoma Patients with Visual Acuity Disturbance

ABSTRACT Purpose Assessing the papillomacular nerve fiber bundle (PMB) can identify glaucoma patients with decreased visual acuity. In this study, we explore efficient methods for evaluating PMB thickness in glaucoma patients, based on swept source-optical coherence tomography (SS-OCT). Methods This study included 347 eyes of 205 open-angle glaucoma (OAG) patients. Patients were excluded if they had best-corrected decimal visual acuity < 0.3, axial length >28 mm, non-glaucoma ocular disease, or systemic disease affecting the visual field. We obtained vertical 12.0 × 9.0 mm 3D volume scans covering both the macular and optic disc regions with SS-OCT (DRI OCT Triton, Topcon), and measured the thickness of the PMB, as well as average macular retinal nerve fiber layer thickness (mRNFLT) and macular ganglion cell complex thickness (mGCCT) in the macular map and temporal-quadrant circumpapillary RNFL thickness (tcpRNFLT). We also measured central-strip RNFLT (csRNFLT) and GCC (csGCCT) in a 1.5 × 6.6 mm area of the scan centered between the fovea and optic nerve head. CsRNFLT and csGCCT were divided lengthwise into three 1.5 × 2.2 mm sections. We then calculated Spearman’s rank correlation coefficient between these OCT measurements and visual acuity. Logistic regression analysis was used to find the cutoff value for the OCT measurements to predict logMAR < 0. Results The correlation coefficients with logMAR were 0.38 for mRNFLT, 0.44 for mGCCT, 0.37 for middle csRNFLT, 0.50 for middle csGCCT, and 0.33 for tcpRNFLT (all P < .0001). For middle csGCCT, the area under the curve indicating decreased visual acuity was 0.80, with a cutoff value of 88.6 μm (P < .001). Conclusions We found strong associations between OCT parameters in the PMB, especially middle csGCCT, and visual acuity in patients with OAG. The thickness of the PMB may therefore be valuable information for glaucoma care and may help prevent visual acuity disturbance.

Morphological characteristics of the lateral talocalcaneal ligament: a large-scale anatomical study.

The purpose of this study is to clarify the morphological characteristics of the lateral talocalcaneal ligament (LTCL). This study examined 100 legs from 54 Japanese cadavers. The LTCL was classified into three types: Type I, the LTCL branches from the calcaneofibular ligament (CFL); Type II, the LTCL is independent of the CFL and runs parallel to the calcaneus; and Type III, the LTCL is absent. The morphological features measured were fiber bundle length, fiber bundle width, and fiber bundle thickness. The LTCL was classified as Type I in 18 feet (18%), Type II in 24 feet (24%), and Type III in 58 feet (58%). All LTCLs were associated with the anterior talofibular ligament at the talus. There was no significant difference in morphological characteristics by Type for each ligament. The LTCL was similar to the CFL in terms of fiber bundle width and fiber bundle thickness.

Mixed mode dynamic crack-fiber bundle interaction using caustics

Caustic method was extended to study the interaction between the mixed mode dynamic matrix crack and the fiber bundle in fiber reinforced composites. First, the dynamic caustic experiments were conducted using transparent specimens with different thicknesses of fiber bundles under dynamic three point bending load. Then, the evolutions of dynamic shadow spots at the crack tip shielded by different thicknesses of fiber bundles were obtained. Moreover, the dynamic stress intensity factors were extracted from the shadow spots. Finally, the crack propagation and bifurcation behaviors were analyzed. It was shown that the stress intensity factors and crack propagation velocities were shielded by the fiber bundles, and the shielding effect increased with the increase of fiber bundle thickness.

Correlation of papillomacular nerve fiber bundle thickness with central visual function in open-angle glaucoma.

Purpose. To determine the correlation of reduced retinal thickness in the central papillomacular bundle (CPB) to central visual function, including central retinal sensitivity and visual acuity, in glaucoma patients. Methods. This study enrolled 50 eyes of 50 patients with open-angle glaucoma who were carefully screened for comorbid conditions that can cause decreased central visual function, such as cataracts or macular diseases. We used a novel CPB analysis comprising a program for optical coherence tomography that measured RNFL thickness and GCC thickness in the CPB and divided lengthwise into three parts (upper, middle, and lower CPB). The relationship of these parameters, including conventional macular thickness, to visual field sensitivity in four central standard automated perimetry points (the central four thresholds) and BCVA was analyzed. Results. The two parameters most highly correlated with central four thresholds were macular GCCT and macular RNFLT. The two parameters most highly correlated with BCVA were middle CPB (mid-CPB) GCCT and mid-CPB RNFLT. A multiple regression analysis revealed that mid-CPB GCCT was an independent factor impacting central retinal thresholds and BCVA. Conclusions. Our results suggest that mid-CPB RNFLT and GCCT, parameters of a novel papillomacular bundle analysis, are candidate biomarkers of decreased central visual function in glaucomatous eyes.

Heterogeneity in Subcutaneous Adipose Tissue Morphology and Metabolic Complications in Overweight and Obese Women

The aim of this study was to assess morphological features of intact adipose tissue (AT) ex vivo from both subcutaneous (s.c.) abdominal and gluteal areas using a novel approach of multiphoton autofluorescence microscopy (MPAM) combined with second harmonic generation microscopy (SHGM), and to assess the relationship between morphological features in the two AT sites and insulin resistance to peripheral glucose disposal. This study was a cross-sectional evaluation of AT morphology feature and peripheral insulin resistance. Fourteen overweight/obese premenopausal women underwent body composition studies, hyperinsulinemic-euglycemic clamps, and needle biopsy of both the s.c. abdominal and gluteal AT areas. MPAM combined with SHGM was used to measure adipocyte maximal diameter and collagen fiber bundle thickness within a sampled image volume after three-dimensional visualization. Higher body mass index (BMI) was associated with larger adipocyte diameter in s.c. abdominal, but not gluteal, AT. Higher adipocyte diameter was associated with higher pericellular collagen thickness. Adipocyte diameter in s.c. abdominal, but not gluteal, AT was associated positively with leptin and negatively with adiponectin plasma levels and peripheral glucose disposal rate. The latter correlation was no longer significant after adjustment for collagen thickness. In overweight/obese premenopausal women, larger adipocyte diameter in s.c. abdominal, but not gluteal, AT associates with low plasma adiponectin and systemic insulin resistance, and suggests that increased collagen thickness (obesity-related scarring) could contribute to these findings.

Partial volume effect as a hidden covariate in DTI analyses

During the last decade, diffusion tensor imaging (DTI) has been used extensively to investigate microstructural properties of white matter fiber pathways. In many of these DTI-based studies, fiber tractography has been used to infer relationships between bundle-specific mean DTI metrics and measures-of-interest (e.g., when studying diffusion changes related to age, cognitive performance, etc.) or to assess potential differences between populations (e.g., comparing males vs. females, healthy vs. diseased subjects, etc.). As partial volume effects (PVEs) are known to affect tractography and, subsequently, the estimated DTI measures sampled along these reconstructed tracts in an adverse way, it is important to gain insight into potential confounding factors that may modulate this PVE. For instance, for thicker fiber bundles, the contribution of PVE-contaminated voxels to the mean metric for the entire fiber bundle will be smaller, and vice-versa — which means that the extent of PVE-contamination will vary from bundle to bundle. With the growing popularity of tractography-based methods in both fundamental research and clinical applications, it is of paramount importance to examine the presence of PVE-related covariates, such as thickness, orientation, curvature, and shape of a fiber bundle, and to investigate the extent to which these hidden confounds affect diffusion measures. To test the hypothesis that these PVE-related covariates modulate DTI metrics depending on the shape of a bundle, we performed simulations with synthetic diffusion phantoms and analyzed bundle-specific DTI measures of the cingulum and the corpus callosum in 55 healthy subjects. Our results indicate that the estimated bundle-specific mean values of diffusion metrics, including the frequently used fractional anisotropy and mean diffusivity, were indeed modulated by fiber bundle thickness, orientation, and curvature. Correlation analyses between gender and diffusion measures yield different results when volume is included as a covariate. This indicates that incorporating these PVE-related factors in DTI analyses is imperative to disentangle changes in “true microstructural” tissue properties from these hidden covariates.

Numerical Analysis of Fiber Fleece Behavior in Roller Drafting in a Transient State

Fiber bundle thickness irregularity from a roll draft mechanism was analyzed in the time domain on the basis of a theoretical model (Partial Differential Equation, PDE, system) for bundle flow. As the governing equations that consisted of continuity and motion equations turned out to be nonlinear, being coupled between variables, etc., a numerical method was established to solve the problem. In particular, the Forward-Time Central-Space (FTCS) difference formula with an explicit Euler scheme as the Finite Difference Method (FDM) was applied. Then the system of equations, which were in algebraic form, was solved according to given initial and boundary conditions in an iterative fashion. Results from this research confirmed that the theoretical response of the output linear density to the disturbance of drafting condition agreed very well with experiment. The transient state of the velocity profile faded out more quickly than that of the linear density profile. The response of the output bundle thickness to the step change perturbation depended on process conditions or material properties. With certain model parameters, the disturbed linear density of the output sliver converged to a fixed value or had an increasing variation magnitude. This indicated that the characteristics of the output bundle thickness could change according to the bundle properties or to the process conditions, which could induce unstable changes in thickness.

A Study on Small Diameter Drilling of GFRP for Printed Wiring Board. Influence of Fiber Bundle Thickness of Plain Woven Cloth on Damage of Drilled Hole.

This study describes the damage around the drilled hole wall in small diameter drilling of GFRP for a printed wiring board in order to prevent from ion migration. In the present report, investigation was carried out from the view of the relative positions between hole center and plain woven cloth. Specially, we paid attention to the radius of the drill and the width of cloth. As results, it is clear that there are two important factors of internal damage widths around the drilled hole; the relative angles between cutting directions and fiber directions, and thickness of glass cloth at the drilled hole wall.

Effects of fibrin micromorphology on neurite growth from dorsal root ganglia cultured in three-dimensional fibrin gels.

The effect of fibrin matrix micromorphology on neurite growth was investigated by measuring the length of neurites growing in three-dimensional fibrin gels with well characterized micromorphologies. Dorsal root ganglia (DRGs) from 7-day chick embryos were entrapped and cultured in gels made from varying concentrations of fibrinogen (5-15 mg/mL) or calcium (2-10 mM). The length of growing neurites was measured with light videomicroscopy, and the number and diameter of fibrin fiber bundles were measured from scanning electron micrographs. An increase in fibrinogen concentration caused a decrease in the average fiber bundle thickness, an increase in the number of fiber bundles, and a marked decrease in neurite length. Gels made with different calcium concentrations had a similar range of variation in fibrin fiber bundle number or diameter, but these variations had little effect on neurite and associated nonneuronal cell outgrowth. These results provide insights into the process of neurite advance within fibrin and may be useful in the design of fibrin-based materials used for peripheral nerve regeneration. Furthermore, this study provides the first detailed experimental data on the micromorphology of fibrin matrices made from more than 5 mg/mL of fibrinogen and indicates that existing kinetic models of fibrin polymerization do not accurately predict fibrin structure at these higher concentrations.

Healing of Tendon Defects Implanted with a Porous Collagen-GAG Matrix: Histological Evaluation

There is currently no method to restore normal function in tendon injuries that result in a gap. The objective of this study was to evaluate the early healing of tendon defects implanted with a porous collagen–glycosaminoglycan (CG) matrix, previously shown to facilitate the regeneration of dermis and peripheral nerve. A novel animal model that isolates the tendon defect site from surrounding tissue during healing was employed. This model used a silicone tube to entubulate the surgically produced tendon gap of 10 mm, allowing for the evaluation of the effects of the analog of extracellular matrix on healing of tendon, absent the influences of the external environment. The results showed that tendon stumps induced synthesis of a tissue cable inside the silicone tube in both the presence and absence of CG matrix. The presence of the CG matrix, however, altered the process of tendon healing. Tubes filled with CG matrix contained a significantly greater volume of tissue at the time periods of evaluation: 3, 6, and 12 weeks. Granulation tissue persisted for a longer period of time in the lesion site of CG-filled defects, and the amount of dense fibrous tissue increased continuously during the period of study in defects filled with CG matrix. In contrast, the amount of dense fibrous tissue decreased after 6 weeks in originally empty tubes. In tubes that did not contain the CG matrix, the new tissue consisted of dense aggregates of crimped fibers with a wavelength and fiber bundle thickness that were significantly shorter than those in normal tendon, and consistent with the type of scar that is the end result of repair of many connective tissues. Although, CG-filled tubes contained dense fibrous tissue by 12 weeks, the tissue had no crimp. The CG matrix may have prolonged the synthesis of granulation tissue and delayed or prevented the formation of scar.