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In order to improve the interlaminar delamination resistance of the carbon-fiber/epoxy composite laminates, short fibers were applied between layers. The effects of length, density, type of short fiber on mode I fracture toughness(GIC) and mode II fracture toughness (GIIC) were investigated by three-factor and four-level orthogonal test combined with range analysis and scanning electron microscope observation. Finally, parameter optimization and test verification. The results show that the order of factors influencing GIC and GIIC within the selected parameters are: fiber type, fiber density and fiber length. When Kevlar fibers with a length of 11mm and a density of 20g·m-2 were laid between layers, the GIC was 451.4J·m-2, which was 82.2% higher than that of the specimens without short fibers in the layers. Kevlar fibers with a length of 11 mm and a density of 5g·m-2 were layered with a GIIC of 2034.3 J·m-2, which was increased by 240.5% compared with the specimens without short fibers in the interlayer.

Hierarchical scaffolds consisting of micro-sized struts with inter-layered nanofibers between the struts are mechanically stable and biologically superior to conventionally fabricated rapid-prototyped scaffolds and electrospun nanofibers. However, although the hierarchical scaffolds overcome various disadvantages of conventional scaffolds, there are still some limitations, such as low cell migration in the thickness direction and non-homogeneous cell proliferation. To overcome these deficiencies, a new hierarchical scaffold supplemented with osteoblast-like cell (MG63)-laden alginate struts is proposed. To control cell proliferation in the thickness direction of the scaffold, the density of interlayered nanofibers was manipulated using various electrospinning deposition times (2, 5, 10, and 20 s). Using the appropriate interlayered fiber density (electrospin deposition time = 10 s) and cell-laden alginate struts, we can obtain significantly homogeneous cell distribution in the hierarchical scaffold.

Quantitatively characterizing the development of cortical anatomical networks during the early stage of life plays an important role in revealing the relationship between cortical structural connection and high-level functional development. The development of correlation networks of cortical-thickness, cortical folding, and fiber-density is systematically analyzed in this article to study the relationship between different anatomical properties during the first 2 years of life. Specifically, longitudinal MR images of 73 healthy subjects from birth to 2 year old are used. For each subject at each time point, its measures of cortical thickness, cortical folding, and fiber density are projected to its cortical surface that has been partitioned into 78 cortical regions. Then, the correlation matrices for cortical thickness, cortical folding, and fiber density at each time point can be constructed, respectively, by computing the inter-regional Pearson correlation coefficient (of any pair of ROIs) across all 73 subjects. Finally, the presence/ absence pattern (i.e., binary pattern) of the connection network is constructed from each inter-regional correlation matrix, and its statistical and anatomical properties are adopted to analyze the longitudinal development of anatomical networks. The results show that the development of anatomical network could be characterized differently by using different anatomical properties (i.e., using cortical thickness, cortical folding, or fiber density).

In this study, we analyzed the key parameters of modified transcutaneous lower blepharoplasty based on multidisciplinary principles (biochemical findings and biophysical wrinkling theory). A total of 408 female patients received our subciliary lower blepharoplasty between March 2002 and January 2010. The severity of the eyebags (dynamic wrinkle numbers and prolapse) was evaluated through preoperative and postoperative photography, whereas the excised lower eyelid skin specimens from 56 patients were investigated with hematoxylin and eosin staining. The modified techniques produced significant improvements in the severity of eyebags in all age groups (P < 0.001). Poor surgical outcome was found to correlate significantly with preoperative dynamic wrinkle numbers (P < 0.001). Age, dynamic wrinkle numbers, and prolapse correlated significantly with dermal fiber density (P = 0.004, 0.000, and 0.000, respectively) but not epidermal, rete ridge, and dermal thickness or the number of rete ridges. In conclusion, modified transcutaneous lower blepharoplasty provides significant improvement to dynamic wrinkles and prolapse in the eyebags. Periorbital aging progressively disturbs the dermal compactness (fiber density) until the structure can no longer hold its integrity at the critical age (around the age of 40).

A constitutive theory is presented for composite materials with a time dependent fiber morphology that is due to mechanical–chemical interaction. The central modeling concept is that the density of fibers at the current time t associated with a particular direction is the result of a process of creation and dissolution of fibers at all previous times. The theory is applied to the specific example of strain dependent enzyme degradation of collagen fiber reinforced materials that has been reported in a recent experimental study. A specific set of modeling assumptions is introduced and an expression is developed for the time dependent distribution density. A special result is developed that relates it to a homeostatic fiber density that occurs when the creation and dissolution processes are in balance for a finite strain that does not vary with time.

This study was intended to estimate the bond strength of steel fiber in UHPFRC through pullout test. The pullout test was carried out with the double-sided pullout specimens with multiple fibers. First, the effect of fiber density on the bond strength was investigated, and the experimental result presented that the density range considered in this study was proved not to produce fiber-to-fiber interaction. The bond strength was estimated from several methods, which are based on the pullout load or energy at peak load, and the total energy absorbed until fibers are pulled out completely. the estimated bond strength obtained from the total energy was shown to be under the influence of the embedded length of fiber. the bond strengths obtained from peak load condition was 6.64 MPa in average, which had little difference compared to 6.46 MPa calculated by peak load only. Considering simplicity of test and analysis, it may be no matter to estimate the bond strength from peak load in pullout test.

Introduction: Motor unit action potential (MUAP) reference values are usually given per muscle and age group. Our aim was to evaluate the change in MUAP size at different contraction levels using the concentric macro (ConMac) EMG technique. Methods: ConMac needles were used to record the electrode cannula MUAP and measure its amplitude and area during weak, moderate, and strong muscle contractions. Results: MUAP area and amplitude gradually increased from weak to strong contraction levels in all muscles studied. MUAP amplitudes were larger in distal than in proximal muscles, likely because of a higher fiber density distally. Conclusions: MUAP normal values in the literature per muscle do not take into account the contraction level at which they were recorded and can misrepresent the interpretation of normal. Concentric macro EMG is a simple and useful complement to routine EMG studies and yields additional information on MUAP neurophysiology. Muscle Nerve 48: 551–556, 2013

One of today’s biggest concerns has been environmental issues, which has motivated researches and the development of materials from renewable resources and environmentally friendly. Natural fibers have excelled in replacing synthetic fibers used in composites manufacturing, because natural fibers are biodegradable, abundance in the nature, low cost, low density, high strength, among others. Due to these qualities, some natural fibers are used for many purposes in automobile industry. However, the natural fiber has irregularities and pores in its structure which directly impact the density determination by geometric techniques and, accordingly, the volume of fibers used in composites. Therefore, the main objective is this study is to determine the density of curaua fiber by pycnometry and to compare it with the commonly used geometric technique.

Denervated post-infarct scar is arrhythmogenic. Our aim was to compare QRS frequency content in denervated and innervated left ventricular (LV) scar. In-vivo single lead ECG telemetry device was implanted in 17 heterozygous PTPσ (HET) and 7 lacking PTPσ (KO) transgenic mice. Myocardial infarction (MI) with reperfusion and sham surgery was performed. HET mice developed a denervated scar, whereas KO mice developed innervated scar. The power spectral density was used to assess the QRS frequency content. Denervated as compared to innervated post-MI scar was characterized by the higher relative contribution of 300–500 Hz (14 ± 1 vs. 9 ± 1%; P = 0.001) but reduced relative contribution of 200–300 Hz (86 ± 1 vs. 91 ± 1%; P = 0.001). Norepinephrine concentration in peri-infarct zone correlated with both 1–200 Hz (r = 0.75; P = 0.03) and 200–500 Hz QRS power (r = 0.73; P = 0.04). Sympathetic fiber density within the infarct correlated with 200–300/200–500 Hz QRS power ratio (r = 0.56; P = 0.005). Intracellular sigma peptide injections in post-MI HET mice restored the QRS power.

The aim of this work is to assess an automatic optimized algorithm for the positioning of the Motor Units (MUs) within a multilayered cylindrical High Density surface EMG (HD-sEMG) generation model representing a skeletal muscle. The multilayered cylinder is composed of three layers: muscle, adipose and skin tissues. For this purpose, two different algorithms will be compared: an unconstrained random and a Mitchell's Best Candidate (MBC) placements, both with uniform distribution for the MUs positions. These algorithms will then be compared by their fiber density within the muscle and by using a classical amplitude descriptor, the Root-Mean-Square (RMS) amplitude value obtained from 64 HD-sEMG signals recorded by an 8×8 electrode grid of circular electrode during one contraction at 70% Maximum Voluntary Contraction (MVC) in both simulation and experimental conditions for the Biceps Brachii (BB) muscle. The obtained results clearly exposed the necessity to use a specific algorithm to place the MUs within the muscle representation volume in agreement with physiology.

To investigate the recovery of orthokeratology (OK)-induced changes in corneal nerve morphology and sensitivity following lens wear discontinuation, over a 3-month period.Sixteen myopic subjects who wore OK lenses during sleep for 3 months discontinued lens wear for 3 months. Corneal nerve morphology and sensitivity were assessed on the right eye only 3 h after waking at the pre-lens wear baseline and after lens wear discontinuation. Corneal nerve fiber density (NFD) and global nerve fiber orientation (GNFO) were assessed by sampling a 1 mmSignificant changes in corneal sensitivity, NFD, and GNFO were observed at various corneal locations during the lens wear discontinuation period. In the central cornea, NFD and corneal sensitivity increased during the 3-month non-lens wear period (p 0.01); no significant changes in NFD or corneal sensitivity were noted in the mid-peripheral cornea. Central corneal sensitivity recovered to pre-lens wear levels after 1 month of non-lens wear. Central NFD appeared to remain slightly decreased after 3 months of non-lens wear compared to pre-lens wear levels, but this difference did not reach statistical significance (p = 0.09). GNFO did not change significantly at the central cornea during the 3-month non-lens wear period, but altered in a counter-clockwise rotational direction (reversal of OK-induced change) at the mid-peripheral cornea (p 0.05), although it did not appear to fully recover to pre-lens wear orientation (p = 0.05).OK lens-induced reduction in corneal sensitivity recovers with cessation of lens wear, returning to pre-lens wear levels shortly after lens wear discontinuation. Changes to nerve morphology induced by OK lens wear, however, appear to recover more slowly towards pre-lens wear levels. This requires confirmation in a longer non-lens wear period.

Background Side-to-side (STS) neurorrhaphy can be performed distally to ensure timely end-organ innervation. It leaves the distal end of the injured nerve intact for further reconstruction. Despite encouraging clinical results, only few experimental studies have been published to enhance the regeneration results of the procedure. We examined the influence of different size epineural windows and degree of axonal injury of STS repair on nerve regeneration and donor nerve morbidity. Methods Three clinically relevant repair techniques of the transected common peroneal nerve (CPN) were compared. Group A: 10-mm long epineural STS windows; group B: 2-mm long windows and partial axotomy to the donor tibial nerve; and group C: 2-mm long windows with axotomies to both nerves. Regeneration was followed by the walk track analysis, nerve morphometry, histology, and wet muscle mass calculations. Results The results of the walk track analysis were significantly better in groups B and C compared with group A. The nerve fiber count, total fiber area, fiber density, and percentage of the fiber area values of CPN of the group C were significantly higher when compared with group A. The wet mass ratio of the CPN-innervated anterior tibial muscle was significantly higher in group C compared with group A. The wet mass ratio of the tibial nerve-innervated gastrocnemial muscle was higher in group A compared with the other groups. Conclusions All three variations of the STS repair technique showed nerve regeneration. Deliberate donor nerve axotomy enhanced nerve regeneration. A larger epineural window did not compensate the effect of axonal trauma on nerve regeneration.

We report a facile protocol for the synthesis of fibrous nano-silica (KCC-1) with controllable size and fiber density. In this work, we have shown that the particle size, fiber density, surface area and pore volume of KCC-1 can be effectively controlled and tuned by changing various reaction parameters, such as the concentrations of urea, CTAB, 1-pentanol, reaction time, temperature, solvent ratio and even outside stirring time. For the first time, we were able to control the particle size ranging from as small as 170 nm to as large as 1120 nm. We were also able to control the fiber density from low to medium to very dense, which consequently allowed the tuning of the pore volume. We were able to achieve a pore volume of 2.18 cm3/g, which is the highest reported for such a fibrous material. Notably we were even able to increase the surface area up to 1244 m2/g, nearly double the previously reported surface area of KCC-1. Thus, one can now synthesize KCC-1 with various degrees of size, surface area, pore volume and fiber density.

The corpus callosum (CC) is the major white matter tract that connects the two cerebral hemispheres. Some have theorized that individual differences in behavioral and brain asymmetries are linked to variation in the density of axon fibers that traverse different sections of the CC. In this study, we examined whether variation in axon fiber density in the CC was associated with variation in asymmetries in the planum temporale (PT) in a sample of 20 post-mortem chimpanzee brains. We further tested for sex differences in small and large CC fiber proportions and density in the chimpanzees. We found that the distribution of small and large fibers within the CC of chimpanzees follows a similar pattern to those reported in humans. We also found that chimpanzees with larger asymmetries in the PT had fewer large fibers in the posterior portion of the CC, particularly among females. As has been reported in human brains, the findings reported here indicate that individual differences in brain asymmetries are associated with variation in interhemispheric connectivity as manifest in axon fiber density and size.

It is very important to measure paper fiber density and equivalent diameter for pulp suspension as solid-liquid two-phase flow in fluid dynamics study. There are some kinds of ways to measure fiber density，but not be suit for pulp fiber density because of their limitations. By using kajaaniFS300 fiber analyzer provided by Mesto ltd company to compare and measure all kinds of fiber length, fiber coarseness, weight average fiber length can more accurately show the actual length of fiber. The results shows that it is apparently more appropriate to calculate fiber density by using fiber coarseness, weight-average fiber length and weight-average fiber width, and fiber equivalent diameter should also be calculated according to the same weight-average fiber length and weight-average fiber width.

Many studies have been dedicated to the development of scaffolds for improving post-traumatic nerve regeneration with different biomaterials. Nerve autografting is the most common surgical procedure currently used to repair nerve defects as a gold standard. To address the disadvantages of limited availability of donor nerves and donor site morbidity, we have fabricated chitosan conduits and seeded them combined with bone marrow mesenchymal stem cells (BMSCs) as an alternative. The conduits were tested for efficacy in bridging the critical gap (8 mm) in sciatic nerves of adult rats, which including sciatic nerve function index (SFI), ethology observation, histologic detection, immunohistochemistry detection. The BMSCs were tested for survival rate and differentiation by fluorescence labeling. Six weeks after operation, the SFI, average regenerated fiber density, and fiber diameter in nerves bridged with BMSCs were similar to those treated with autograft, but significantly higher than those bridged with chitosan conduits only (P

Shaft loaded blaster test (SLBT) is utilized to characterize the adhesion energy of electrospun polyvinylidene fluoride (PVDF) membrane with rigid substrate in this paper. PVDF membrane prepared by electrospinning exhibits a uniform fiber morphology. At the membrane surface, the fiber diameter is 333 ± 59 nm and fiber density is roughly around 77%. When electrospun PVDF membrane is tested in SLBT, it shows full linear elastic response at the beginning. With the increase of central deflection up to 2 mm, the electrospun PVDF membrane exhibits obviously yielding. A clear yield point is observed in the debonding response curves. By analysis the elastic response of electrospun PVDF membrane, adhesion energy between the membrane and rigid substrate is calculated. The average adhesion energy is 210.1 ± 27.7 mJ/m 2 .

Although persistently raised serum creatine kinase (sCK), or hyperCKemia, is considered the biological hallmark of neuromuscular diseases, pauci- or asymptomatic- or isolated-hyperCKemia can often be found. Single-fiber electromyography (SFEMG) is an electrophysiological technique of great value in the assessment of neuromuscular, neuropathic and myopathic disorders. We hypothesize that SFEMG fiber density (FD) evaluation is able to detect subclinical electrophysiological abnormalities indicating a myopathic process in subjects with hyperCKemia. Nineteen subjects with hyperCKemia without evident clinical signs of muscle involvement and 15 healthy controls were studied. Electrophysiological investigations including nerve conduction studies (NCS), quantitative EMG (QEMG), SFEMG with focus on FD measurements, and muscle biopsy were performed. NCS, QEMG, SFEMG were normal in all controls. In subjects with hyperCKemia, NCS were normal; QEMG was abnormal in 5, while both SFEMG and muscle biopsy disclosed abnormalities in 12 subjects. The mean FD value was 2.6 ± 0.5 in the control and 4 ± 1.4 (p = 0.003) in the hyperCKemia group. SFEMG revealed subclinical changes in the majority of subjects with hyperCKemia. To the best of our knowledge, this is the first study demonstrating that SFEMG FD evaluation is able to detect the presence of muscle diseases, which are in a subclinical phase and would remain unidentified otherwise. SFEMG may be used to distinguish hyperCKemia associated to asymptomatic muscle disorders from idiopathic hyperCKemia. We believe that SFEMG FD evaluation should be added to the routine examinations in the screening of idiopathic hyperCKemia.

The aim of this study is to analyze the effects of low-level laser therapy (LLLT) on the regeneration of the sciatic nerve in rats following a complete nerve resection. Male Wistar rats were divided into a control injury group, injury groups irradiated with a 660-nm laser at 10 or 50 J/cm(2), and injury groups irradiated with an 808-nm laser at 10 or 50 J/cm(2). Treatment began 24 h following nerve resection and continued for 15 days. Using the sciatic functional index (SFI), we show that the injured animals treated with 660 nm at 10 and 50 J/cm(2) had better SFI values compared with the control injury and the 808-nm groups. Animals irradiated with the 808-nm laser at 50 J/cm(2) show higher values for fiber density than do control animals. In addition, axon and fiber diameters were larger in animals irradiated with 660 nm at 50 J/cm(2) compared to the control group. These findings indicate that 660-nm LLLT is able to provide functional gait recovery and leads to increases in fiber diameter following sciatic nerve resection.

This paper introduces the fiber filter device by adjusting the charge and discharge water to adjust the fiber density - filter accuracy, interception capacity, filtration resistance and other parameters. In the industrial, commercial market prospects, environmental, economic and social benefit is remarkable.

Recent quantitative analyses of the corpus callosum (CC) have tried to assess the interhemispheric connectivity. Based on histological results showing an expansion of callosal extent at the midsagittal plane, without fiber density alterations, callosal extent was interpreted as an index of interhemispheric connectivity. The microstructural properties of the CC have also been investigated extensively using diffusion tensor imaging, to assess interhemispheric connectivity. The relationships between axonal density and callosal extent need to be investigated to understand how these parameters reflect interhemispheric connectivity. We used a semi-automated CC segmentation scheme in T1-weighted magnetic resonance image and fractional anisotropy (FA) image, respectively. The parameterization method of the segmented CC was applied to 47 right-handed healthy adult subjects. The callosal extent and microstructural properties were measured using the callosal thickness and diffusion indices (FA, mean diffusivity, and axial and radial diffusivity), respectively. Our results revealed a correlation between callosal thickness and FA on the posterior body and isthmus of the CC, which suggests that these regions are more sensitive to fiber alterations than other regions. Based on this result, we suggest that both the extent of the CC and its microstructural properties should be considered together in the estimation of interhemispheric connectivity in healthy adult populations.

Comparative anatomical studies were made measuring several morphological characteristics seen in cross-sections of the optic nerve of one-humped camel (Camelus dromedarius) and donkey (Equus asinus). Six optic nerves from each animal were used in this study. The optic nerve samples were obtained about 5mm behind the eye. The axon numbers and diameters were studied with light and transmission electron microscopes. Axon diameters were measured in samples of 500 axons taken from several locations in a cross section of the optic nerve behind the eye. The total cross-sectional area of the optic nerve was about 35% smaller in the donkey than in the camel. The fibers are organized in fascicles. The fiber density and number was 2.3 times higher in the camel than in the donkey. The total number of optic nerve fibers counted was 1173323 ± 33039 in camels and 495754 ± 10126 in donkeys. The majority of axons were myelinated in the optic nerve of both animals. There was a significant regional variation in the size of optic nerve axons. Large myelinated axons were observed in the dorsal and ventral periphery, whereas smaller myelinated fibers and a high proportion of unmyelinated fibers were found in the center of the nerve.

The effect of reversing the direction of rotation of workers on the swift of a worsted card was studied in a trial that included processing to top. Experimental conditions studied were worker draft (three levels), doffer draft (two levels), and wool type (two levels). Production rate was held constant throughout at values typical for worsted carding, ~1 gsm production fiber density on the swift and standard topmaking procedures were used after carding. The results showed that the only effect of reversing the direction of rotation identified was increased fiber breakage and noil at the lowest opening roller draft (0.4 %). A tracer fiber study failed to identify any effect of the direction of worker rotation on the fiber structure of the card web. The reason for the increased fiber breakage with reversed direction of rotation at very low draft was thought to be the increased loading in the nip due to the trailing ends of the fibers. The implications of reversing worker rotation for roller carding in general are briefly considered.

Flocked fabrics are particularly used in outwear and home upholstery since they are comfortable and soft. In this study, Martindale abrasion and token rubbing properties of the flocked fabrics were investigated and characterized. It was observed that the surface abrasion properties of the flocked fabrics varied depending on the flock fiber density and flock fiber length. The abrasion resistance of flocked fabrics was increased by increasing flock fiber length and decreasing flock fiber density. The surface rubbing properties of flocked fabrics showed similar tendencies with the abrasion properties. However, the flocked fabrics showed more resistance to rubbing in dry form than wet form. These results were in agreement with the optical microscope images.

In this paper, we simulate the effects of tax reforms aimed at encouraging healthier grain consumption. We use a rich data set on household grain consumption in 2003 from the market research institute GfK Sweden, combined with information on the nutritional content of the consumption. We estimate behavioral parameters, which are used to simulate the impact on the average household of tax reforms entailing either a subsidy on commodities particularly rich in fiber or a subsidy of the fiber density in grain products. Our results suggest that to direct the fiber intake towards nutritional recommendations, reforms with a substantial impact on consumer prices are required. Regardless of the type of subsidy implemented, the increase in the intake of fiber is accompanied by unwanted increases in nutrients that are often overconsumed: fat, salt and sugar. Funding the subsidies by taxing these nutrients, or less healthy commodities, helps to counteract such developments.

Fatigue application of a polymeric material is limited due to its hysteretic heating behavior. In this work, effort has been made to understand the effect of fiber reinforcement and length of the reinforcing fibers on hysteretic heating behavior and its mechanisms. Unreinforced, 20% short glass fiber-reinforced and 20% long glass fiber-reinforced polypropylene materials have been injection-molded and subjected to a finite number of fatigue cycles. The load required for constant deflection and the surface temperature of materials during testing was measured and correlated with the hysteretic heating mechanism. During material deformation, the presence of the reinforced fibers and fiber-matrix interface in the reinforced material contributed more internal friction, and resulted in higher heat generation than unreinforced material. Higher fiber density and the inferior fiber-matrix bonds existing in the short fiber-reinforced material generated higher heat than that of long fiber-reinforced material during t...

Background: Tensor estimation can be improved by increasing the number of gradient directions (NGD) or increasing the number of signal averages (NSA), but at a cost of increased scan time. Purpose: To evaluate the effects of NGD and NSA on fractional anisotropy (FA) and fiber density index (FDI) in vivo. Material and Methods: Ten healthy adults were scanned on a 1.5T system using nine different diffusion tensor sequences. Combinations of 7 NGD, 15 NGD, and 25 NGD with 1 NSA, 2 NSA, and 3 NSA were used, with scan times varying from 2 to 18 min. Regions of interest (ROIs) were placed in the internal capsules, middle cerebellar peduncles, and splenium of the corpus callosum, and FA and FDI were calculated. Analysis of variance was used to assess whether there was a difference in FA and FDI of different combinations of NGD and NSA. Results: There was no significant difference in FA of different combinations of NGD and NSA of the ROIs ( P>0.005). There was a significant difference in FDI between 7 NGD/1 NSA and 25 NGD/3 NSA in all three ROIs ( P0.005). Conclusion: We have not found any significant difference in FA with varying NGD and NSA in vivo in areas with relatively high anisotropy. However, lower NGD resulted in reduced FDI in vivo. With larger NGD, NSA has less influence on FDI. The optimal sequence among the nine sequences tested with the shortest scan time was 25 NGD/1 NSA.

The influence of temperature, pulping time and soda concentration on the yield, kappa index, brightness and fiber density of Agave Americana L. pulp has been studied. Using a factorial design to identify the optimum operating conditions, equations relating the dependent variables to the operational variables of the pulping process were established. The morphology of the cellulose fibers (length distribution, diameter distribution and crystalline index), obtained from the optimum pulping already determined by the statistical study, was determined by measuring 5020 fibers with optical microscopy equipped with CCD camera and image analysis software, and FT-IR spectra. Cellulose fibers extracted from Agave Americana L. had a lower lignin content value (1.13%) and an absorption capacity of 10.5 g/g. Finally, the characteristics of the optimum Agave pulp were compared to those of other vegetable fibers.

Modeling of muscle architecture, which aims to recreate mathematically the physiological structure of the muscle fibers and motor units, is a powerful tool for understanding and modeling the mechanical and electrical behavior of the muscle. Most of the published models are presented in the form of algorithms, without mathematical analysis of mechanisms or outcomes of the model. Through the study of the muscle architecture model proposed by Stashuk, we present the analytical tools needed to better understand these models. We provide a statistical description for the spatial relations between motor units and muscle fibers. We are particularly concerned with two physiological quantities: the motor unit fiber number, which we expect to be proportional to the motor unit territory area; and the motor unit fiber density, which we expect to be constant for all motor units. Our results indicate that the Stashuk model is in good agreement with the physiological evidence in terms of the expectations outlined above. However, the resulting variance is very high. In addition, a considerable ‘edge effect’ is present in the outer zone of the muscle cross-section, making the properties of the motor units dependent on their location. This effect is relevant when motor unit territories and muscle cross-section are of similar size.

The complex rectangular configuration refers to the geometrical shape jointed by two or more rectangles together. The calculation and design of parameters for 3D braided preform with simple rectangular cross-section are not suitable for those with complex rectangular cross-section because there are special microstructures in complex shaped preform. According to the unit cell models of 3D braided preform with complex rectangular cross-section, the method for computing the amount and volume of each unit cell is presented, the equation for calculating the fiber volume fraction is derived, and the relationships between preform parameters are developed. Based on the equations and relationships established, the procedure for designing the numbers of yarns arrangement is presented from preform dimensions, yarns linear density, fiber density, and fiber volume fraction. A preform with complex rectangular cross-section is designed and produced. The procedure for designing is supported by experimental results.

The aim of this study was to compare the outcomes of nerve autografts (GRF) and venous grafts containing mononuclear bone marrow cells (BMCs) in sciatic nerve-lesioned rats. Control animals underwent sham operations (SHAM), received empty venous grafts (EPV), or received venous grafts containing BMC vehicle (AGR). Outcome was evaluated through sciatic functional index (SFI), morphometric and morphologic analyses of the nerve distal to the lesion, and the number of spinal cord motor neurons positive for the retrograde tracer, Fluoro-Gold®. All groups exhibited poor results in SFI when compared to SHAM animals throughout the postoperative period. All groups also had a significantly greater fiber density, decreased fiber diameter, and decreased motor neuron number than the SHAM group. No significant difference between the GRF and BMC groups was observed in any of these parameters. On the other hand, vessel density was significantly higher in BMC than all other groups. BMC-containing venous grafts are superior to nerve autografts in increasing vessel density during sciatic nerve regeneration.

BACKGROUND AND PURPOSE: Development of callosal fibers is important for psychomotor and cognitive functions. We hypothesized that brain maturation changes are detectable beyond 2 years of age by using diffusion tensor imaging (DTI) of the corpus callosum (CC). MATERIALS AND METHODS: T2 and fractional anisotropy (FA) maps of the brain of 55 healthy subjects between 0.2 and 39 years of age were obtained. Quantitative T2 and FA values were measured at the genu and splenium of the CC (gCC and sCC). Fiber tracking, volumetric determination, and the fiber density calculations of the CC were related to age. A paired t test was used for significant differences between the values at the gCC and sCC. RESULTS: T2 relaxation times at gCC and sCC decrease fast in the first months of life and very little after 2 years of age. The FAgCC increases until 5 years of age and remains nearly constant thereafter; it showed a significant increase from 0 to 2 years versus 2–5 years, whereas there was no difference in the other age groups. FAsCC values showed no significant changes after 2 years of age. The fiber density of the CC shows a tendency of inverse age dependence from childhood to adulthood. CONCLUSION: Rapid ongoing changes in brain maturation (increase in FAgCC) are detectable until 5 years of age. DTI reveals more information about brain maturation than T2 relaxometry.

A mispairing PCR-RFLP technique was applied in this study to determine the Insulin-like Growth Factor 2(IGF2) gene intron3 G3072A mutation in an outbred Landrace and Large White, and the gelded boars from Landrace x Large White cross. The difference of corresponding traits and the genetic effects of the boars inherited from parental A allele and inherited from parental G allele were analyzed. The results indicated that comparing with the boars inherited from parental G allele, the boars inherited from parental A allele increased significantly in the circumference 3.06% (P< 0.05) and index of body 3.01% (P< 0.05), respectively. The boars inherited from parental A allele had a significantly less average buttock fat thickness (15.31%, P< 0.01), thorax-waist fat thickness (23.74%, P< 0.01), skin thickness 9.38% (P< 0.01), fiber density (20.03%, P< 0.01) and had more less 6th-7th rib fat thickness (20.27%, P< 0.05), tendernce (17.32%, P< 0.05), and had more thick shoulder fat thickness (7.97%, P< 0.05), and had bigger the loin eye area (22.58%, P< 0.01) and fiber cross-sectional area (32.70%, P< 0.01) and fiber diameter (15.38%, P< 0.01) and lean meat (2.18%, P< 0.01) than the boars inherited from parental G allele. The results were suggested that the parental A allele has highly significant genetic effects in improving pig body development and carcass lean percent by increasing fiber diameter and the loin eye area, and decreasing the skin thickness and fat percent.

Purpose.To study the corneal nerve morphology and its importance in unilateral keratoconus.Materials and Methods.In this prospective cross-sectional study, 33 eyes of 33 patients with keratoconus in one eye (Group 3) were compared with the other normal eye of the same patients (Group 2) and 30 eyes of healthy patients (Group 1). All patients underwent detailed ophthalmic examination followed by topography with Pentacam HR and in vivo confocal microscopy (IVCM). Five images obtained with IVCM were analyzed using an automated CCmetrics software version 1.0 for changes in subbasal plexus of nerves.Results.Intergroup comparison showed statistically significant reduction in corneal nerve fiber density (CNFD) and length (CNFL) in Group 3 as compared to Group 1 (p<0.001andp=0.001, resp.) and Group 2 (p=0.01andp=0.02, resp.). Though corneal nerve fiber length, diameter, area, width, corneal nerve branch density, and corneal total branch density were found to be higher in decentered cones, only the corneal nerve branch density (CNBD) was found to be statistically significant (p<0.01) as compared to centered cones.Conclusion.Quantitative changes in the corneal nerve morphology can be used as an imaging marker for the early diagnosis of keratoconus before the onset of refractive or topography changes.

Deficits in white matter (WM) integrity occur following traumatic brain injury (TBI), and often persist long after the visible scars have healed. Heterogeneity in injury types and locations can complicate analyses, making it harder to discover common biomarkers for tracking recovery. Here we apply a newly developed adaptive connectivity method, EPIC (evolving partitions to improve connectomics) to identify differences in structural connectivity that persist longitudinally. This data comes from a longitudinal study, in which we scanned participants (aged 8-19 years) with anatomical and diffusion MRI in both the post-acute and chronic phases (1-6 months and 13-19 months post-injury). To identify patterns of abnormal connectivity, we trained a model on data from 32 TBI patients in the post-acute phase and 45 well-matched healthy controls, reducing an initial 68x68 connectivity matrix to a 14x14 matrix. We then applied this reduced parcellation to the chronic data in participants who had returned for their chronic assessment (21 TBI and 26 healthy controls) and tested for group differences. We found significant differences in two connections, comprising callosal fibers and long anterior-posterior fibers, with the TBI group showing increased fiber density relative to controls. Longitudinal analysis revealed that these were connections that were decreasing over time in the healthy controls, as is a common developmental phenomenon, but they were increasing in the TBI group. While we cannot definitively tell why this may occur with our current data, this study provides targets for longitudinal tracking, and poses questions for future investigation.

Objective This study aims to evaluate the characteristics of the corneal sub-basal plexus by performing in vivo confocal microscopy of healthy Brazilians to provide reference values for the Brazilian population. Method This study is an observational, cross-sectional, descriptive study comparing corneas from 55 healthy Brazilian individuals across the age span of 20-70 years. Results The average number of fibers was 5.35 ± 1.36, fiber density was 33.4 ± 8.5 fibers per field, and the mean number of Langerhans cells was 5.13 ± 8.10. A correlation between the average number of fibers and age showed an inverse relationship between the number and density of fibers and age for women (p < 0.05). In the multivariate analysis, each annual increase of age showed an average increase of 1.017 (95%CI: 1.008 to 1.026) in the number of Langerhans cells, adjusting for sex and thickness. Conclusion Compared to other samples, this Brazilian population showed a higher average number of fibers, though further studies with a larger sample should be performed. RESUMO Objetivo Este estudo tem como objetivo avaliar as características morfológicas do plexo sub-basal da córnea por microscopia confocal in vivo com indivíduos brasileiros saudáveis para fornecer uma referência para a população brasileira. Método Este trabalho é um estudo observacional, descritivo, transversal comparativo com microscopia confocal de córnea a partir de 55 indivíduos brasileiros saudáveis na faixa etária de 70 ± 20 anos de idade. Resultados Número médio de fibras foi 5,35 ± 1,36, a densidade foi de 33,4 ± 8,5 fibras por campo e de células de Langerhans foi 5,13 ± 8,10. Uma correlação entre o número médio de fibras e da idade dos indivíduos mostrou uma relação inversa entre o número e densidade de fibras, e idade para as mulheres, (p < 0,05). Na análise multivariada, cada aumento anual de idade apresentou um aumento médio de 1,017 (IC95%: 1,008-1,026) no número de células de Langerhans, ajustado para sexo e espessura. Conclusão Em comparação com outras amostras, esta população brasileira apresentou um maior número médio de fibras embora estudos com número maior de amostras necessitem ser realizados.

BACKGROUND: Low-level laser therapy (LLLT) has been demonstrated to be effective in optimizing skeletal muscle performance in animal experiments and in clinical trials. However, little is known about the effects of LLLT on muscle recovery after endurance training. OBJECTIVE: This study evaluates the effects of low-level laser therapy (LLLT) applied after an endurance training protocol on biochemical markers and morphology of skeletal muscle in rats. METHOD: Wistar rats were divided into control group (CG), trained group (TG), and trained and laser irradiated group (TLG). The endurance training was performed on a treadmill, 1 h/day, 5 days/wk, for 8 wk at 60% of the maximal speed reached during the maximal effort test (Tmax) and laser irradiation was applied after training. RESULTS: Both trained groups showed significant increase in speed compared to the CG. The TLG demonstrated a significantly reduced lactate level, increased tibialis anterior (TA) fiber cross-section area, and decreased TA fiber density. Myogenin expression was higher in soleus and TA muscles in both trained groups. In addition, LLLT produced myogenin downregulation in the TA muscle of trained animals. CONCLUSION: These results suggest that LLLT could be an effective therapeutic approach for stimulating recovery during an endurance exercise protocol.

International audience; We introduce an individual-based model for fiber elements having the ability to cross-link or unlink each other and to align with each other at the cross links. We first formally derive a kinetic model for the fiber and cross-links distribution functions. We then consider the fast linking/unlinking regime in which the model can be reduced to the fiber distribution function only and investigate its diffusion limit. The resulting macroscopic model consists of a system of nonlinear diffusion equations for the fiber density and mean orientation. In the case of a homogeneous fiber density, we show that the model is elliptic.

With the recent rise of unmanned aerial vehicles (UAVs), a low-altitude hyperspectral remote sensing is a requisite tool for precise environmental monitoring. However, the low- altitude hyperspectral remote sensing cannot be expanded into a ubiquitous, sustainable monitoring tool because of the high cost of hyperspectral imaging sensors. In this study, we developed a low-cost hyperspectral imaging system for UAVs that is composed of low-cost spectrometers, an optical fiber bundle and a swing mirror. Compared with the system that was developed in our previous work, the spatial resolution of the newly developed sensor was improved by increasing the data acquisition frequency of the spectrometer and the spatial fiber density of the optical fiber bundle.

The aim of this study was to determine the existence of a relation between the fascicular area and total vessel area on the cervical vagus nerve of Wistar-Kyoto female rats. Animals aged 30, 180 or 360 days had their right vagus nerves prepared for epoxy resin embedding and light microscopy study. Semithin serial sections were studied every 100 microm of the longitudinal extension of the nerve. The fascicular area and the total endoneural vessel area were obtained for each nerve segment (proximal, middle and distal) and compared between segments and ages. The relation between fascicular area and endoneural vessel area was accessed by linear regression analysis and correlation coefficient calculations. No significant relationship between the two variables was detected in all nerves studied. This suggests that the entrance of blood vessels to the endoneural space is not accompanied by an increase in the fascicular area and this may have implications on the fiber density calculations since, in the presence of large vessels, this density can be underestimated if the vessel area is not discounted. The endoneural vessel area increased from proximal to distal in all groups but got smaller with ageing, suggesting that older animals may be more susceptible to nerve ischemia.

To better understand the public health impact of the National Academy of Sciences’ Dietary Reference Intakes (DRIs) for fiber in preschoolers, I analyzed data from the United States Department of Agriculture Continuing Survey of Food Intake in Individuals for 5437 preschoolers and examined sociodemographic predictors of meeting the DRIs. Overall, only 12% of the children met the DRIs. Older children (age 4 and 5 years) were less likely than younger children, girls were less likely than boys, and children from mediumincome families (those earning 186% to 350% of the poverty guidelines, with poverty set at 100%) were least likely to meet the DRIs. Low-income children participating in the Special Supplemental Nutrition Program for Women, Infants, and Children were twice as likely as nonparticipants to meet the DRIs. The public should be educated about the importance of increasing fiber density in the diet. (Am J Public Health. 2006; 96:1538‐1541. doi:10.2105/ AJPH.2005.068700) The Dietary Reference Intakes (DRIs) for energy, macronutrients, and fiber from the National Academy of Sciences suggest that Americans aged 2 years and older should consume 14 g of total fiber per 4200 kJ of total energy intake. 1 At this level, fiber seems to protect against constipation and reduce the risk of cardiovascular disease, some cancers, obesity, and diabetes. 2‐6 The DRIs are based on total fiber intake, which includes dietary and functional fiber. A more detailed explanation of the distinction between the 2 kinds of fiber can be found elsewhere. 7,8 In short, dietary fibers are naturally occurring nondigestible carbohydrates and lignin, and functional fibers are components of foods that can be isolated or extracted with