997 resultados para goat fibre


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We studied the fleece production of Angora wether goats provided with energy, to maintain liveweight, and polymer-encapsulated methionine while they were fed on poor quality roughage rations in early summer. Forty goats (mean fleece-free liveweight 28.5 kg) were randomly allotted to 5 treatments and housed individually for 12 weeks. The treatments were: control, fed to lose 5 kg liveweight; M, fed to maintain liveweight; and 3 maintenance rations with either 0.5, 1 or 2 g day-1 of polymer-encapsulated methionine. The basal ration was oaten chaff (56.8% digestible dry matter) and all maintenance- fed goats received a supplement of 150 g day- 1 gristed barley. Goats required an estimated 267 kJ ME kg-0.75 day-1 to maintain liveweight. Goats fed the control diet grew less mohair (P<0.05) with reduced mean fibre diameter (P< 0.05) than maintenance-fed goats (4.9 g day-1, 30.0 pm compared with 5.8 g day-1, 31.9 pm). For maintenance-fed animals, the addition of 1 g day- methionine (0.15% of dry matter intake) increased mohair growth by 0.8g day-1 (P<0.075). Feeding barley to prevent liveweight loss and feeding polymer-encapsulated methionine at maintenance is unlikely to result in economic responses in mohair production of goats grazing low quality summer pastures

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Aims
To investigate the relationship between retinal nerve fibre layer thickness and peripheral neuropathy in patients with Type 2 diabetes, particularly in those who are at higher risk of foot ulceration.

Methods
Global and sectoral retinal nerve fibre layer thicknesses were measured at 3.45 mm diameter around the optic nerve head using optical coherence tomography (OCT). The level of neuropathy was assessed in 106 participants (82 with Type 2 diabetes and 24 healthy controls) using the 0–10 neuropathy disability score. Participants were stratified into four neuropathy groups: none (0–2), mild (3–5), moderate (6–8), and severe (9–10). A neuropathy disability score ‡ 6 was used to define those at higher risk of foot ulceration. Multivariable regression analysis was performed to assess the effect of neuropathy disability scores, age, disease duration and retinopathy on RNFL thickness.

Results
Inferior (but not global or other sectoral) retinal nerve fibre layer thinning was associated with higher neuropathy disability scores (P = 0.03). The retinal nerve fibre layer was significantly thinner for the group with neuropathy disability scores ‡ 6 in the inferior quadrant (P < 0.005). Age, duration of disease and retinopathy levels did not significantly influence retinal nerve fibre layer thickness. Control participants did not show any significant differences in thickness measurements from the group with diabetes and no neuropathy (P > 0.24 for global and all sectors).

Conclusions
Inferior quadrant retinal nerve fibre layer thinning is associated with peripheral neuropathy in patients with Type 2 diabetes, and is more pronounced in those at higher risk of foot ulceration.

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Here, we monitor the dissolution of several natural protein fibres such as wool, human hair and silk, in various ionic liquids (ILs). The dissolution of protein-based materials using ILs is an emerging area exploring the production of new materials from waste products. Wool is a keratin fibre, which is extensively used in the textiles industry and as a result has considerable amounts of waste produced each year. Wool, along with human hair, has a unique morphology whereby the outer layer, the cuticle, is heavily cross linked with disulphide bonds, whereas silk does not have this outer layer. Here we show how ILs dissolve natural protein fibres and how the mechanism of dissolution is directly related to the structure and morphology of the wool fibre. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

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Staple entanglement in mohair fleeces occurs when adhesions form between longer and faster growing fibres and shorter and slower growing fibres. This results in accentuated crimp of the longer fibres and an "apparently" reduced staple length. The appearance in the fleece of Angora goats of staple entanglements can lead to the downgrading of the mohair to poorer style and shorter length grades, resulting in up to 60% price reductions. This study examined how staple entanglement score (SES) is related to lifetime factors of Angora goats, and how this relationship can be explained by variations in animal size and fleece attributes. SES was scored using a five-point scale: 5, long free fibres easily separated as no adhesions; 4, some adhesions between fibres; 3, some effort to separate fibres as many adhesions; 2, many adhesions, staple fibres entangled, shortening of staple; 1, very entangled and shortened staple. Measurements were made over 9 shearing periods on a population of Angora castrated males (wethers) goats representing the current range and diversity of genetic origins in Australia, including South African, Texan and interbred admixtures of these and Australian sources. Data on genetic origin, sire, dam, date of birth, dam age, birth weight, birth parity, weaning weight, live weight, fleece growth and fleece attributes were recorded. Two restricted maximum likelihood (REML) models were developed to relate SES with age, animal lifetime factors, fleece quality attributes and live weight. One model allowed fleece quality and live weight traits in the model and the other excluded these traits. Staple entanglement was almost eliminated in mohair harvested from goats shorn every 3. months but was common in mohair from goats shorn twice or once per year. SES was less in goats of Texan genetic background, and was generally less in winter grown mohair. SES was higher for mohair with low fibre curvature (FC, 10°/mm) and a high clean washing yield (CWY, 90%) compared with mohair with low FC and lower CWY (80%), and compared with all mohair with high FC (18°/mm). The response of SES to shearing regime, genetic background, shearing season, age of goat and a response to dam age were almost identical whether or not an adjustment was made for CWY and FC. There was a moderate amount of variability due to sires and individuals. We can conclude that a large part of these effects observed, namely breed, dam age, sire, and a component of the FC and CWY effects, are genetic. Mohair producers can manage the genetic effects by careful selection of sires, especially avoiding those with low CWY or high FC, and avoiding sires with higher levels of staple entanglement or that have produced progeny with higher levels of staple entanglement. Also, unidentified environmental effects are affecting staple entanglement, although a lack of a live weight change effect on entanglement indicates that this effect might not be due to nutrition. © 2013 Elsevier B.V.

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In order to overcome interfacial incompatibility issues in natural fibre reinforced polymer bio-composites, surface modifications of the natural fibres using complex and environmentally unfriendly chemical methods is necessary. In this paper, we demonstrate that the interfacial properties of cellulose-based bio-composites can be tailored through surface adsorption of polyethylene glycol (PEG) based amphiphilic block copolymers using a greener alternative methodology. Mixtures of water or water/acetone were used to form amphiphilic emulsions or micro-crystal suspensions of PEG based amphiphilic block copolymers, and their deposition from solution onto the cellulosic substrate was carried out by simple dip-coating. The findings of this study evidence that, by tuning the amphiphilicity and the type of building blocks attached to the PEG unit, the flexural and dynamic thermo-mechanical properties of cellulose-based bio-composites comprised of either polylactide (PLA) or high density polyethylene (HDPE) as a matrix, can be remarkably enhanced. The trends, largely driven by interfacial effects, can be ascribed to the combined action of the hydrophilic and hydrophobic components of these amphiphiles. The nature of the interactions formed across the fibre-matrix interface is discussed. The collective outcome from this study provides a technological template to significantly improve the performance of cellulose-based bio-composite materials.

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This work investigated the effect of woven E-glass mass (25 g/m2, 50 g/m2, 85 g/m2, 135 g/m2) on the painted surface finish of various thermoset (EPIKOTETM RIM935, EPIKOTETM 04434, Ultratec LpTM ES300, Ultratec LpTM SPV6035) carbon fibre composite laminates, before and after aging at 95 °C for 168 h. The as-moulded laminate surfaces were evaluated using surface profilometry techniques and the painted and aged surfaces were evaluated using a wave-scan distinctness of image (DOI) instrument. It was found that the 25 g/m2 E-glass surface layer assisted with reducing the roughness of the as-moulded surfaces and the long-term waviness of the painted surfaces due to the increase in resin-richness at the surface. The EPIKOTETM 04434 resin system that contained diglycidyl ether of bisphenol F (DGEBF) epoxy had the least change in long-term waviness with thermal aging due to the rigid fluorene-based backbone in comparison to the diglycidyl ether of bisphenol A (DGEBA) systems.