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The main aim of this study is to determine the thermo-physiological comfort properties of single knit fabrics and their derivatives. As the Single Jersey knitted fabrics are the most widely used fabrics in the apparel sector, they have been selected for the analysis purpose. Derivatives of single jersey are developed and compared in order to understand the influence of structural variations. Physical properties e.g. thickness and areal density were evaluated for all knitted fabrics with 100% cotton yarn having three different yarn linear densities and after different stages of relaxation. Various thermo-physiological properties have been studied by changing the combed cotton yarn linear density as well as the structure of single knit fabric. Air permeability, thermal insulation and relative water vapor permeability of the fabrics were observed and investigated under wet relaxed states. It is determined that fabric physical properties are affected by changing yarn linear density and by the dry or wet relaxation stages. The percentage/number of tuck stitches (NTS), location of tuck stitches (LTS) and ratio of tuck to knit stitches (RTKS) have strong influence on physical and thermo-physiological properties of single knit fabrics, even though other knitting parameters remained the same.

The aim of this work was to investigate the properties of upholstery fabric produced from recycled hard waste of coloured fabric clippings. Mélange yarns were formed with the combination of red, green, black and yellow in different ratios. Five yarn samples of 5 Nec linear density were produced from each blend ratio using the rotor spinning technique. These yarns were used to develop fabric samples in a satin weave. These yarn and fabric samples were investigated for different quality parameters, especially the abrasion resistance, pilling resistance, absorbency and light fastness of the fabrics as per standard test methods. The abrasion test is important for the durability and longer-lasting performance of upholstery fabric. From the analysis of test results, it is concluded that all the serviceability properties are in a good range, and these fabrics can be used for waiting room area upholstery fabric

The paper reports experimental research regarding the mechanical characteristics of concrete reinforced with natural cellulosic fibers like jute, sisal, sugarcane, and coconut. Each type of natural fiber, with an average of 30 mm length, was mixed with a concrete matrix in varying proportions of 0.5% to 3% mass. The tensile and compressive strength of the developed concrete samples with cellulosic fiber reinforcement gradually increased with the increasing proportion of natural cellulosic fibers up to 2%. A further increase in fiber loading fraction results in deterioration of the mechanical properties. By using jute and sisal fiber reinforcement, about 11.6% to 20.2% improvement in tensile and compressive strength, respectively, was observed compared to plain concrete, just by adding 2% of fibers in the concrete mix. Bending strength increased for the natural fiber-based concrete with up to 1.5% fiber loading. However, a decrease in bending strength was observed beyond 1.5% loading due to cracks at fiber−concrete interface. The impact performance showed gradual improvement with natural fiber loading of up to 2%. The water absorption capacity of natural cellulosic fiber reinforced concrete decreased substantially; however, it increased with the loading percent of fibers. The natural fiber reinforced concrete can be commercially used for interior or exterior pavements and flooring slabs as a sustainable construction material for the future.

The hippocampus is implicated in numerous neurological disorders and the ability to detect subtle or focal hippocampal abnormalities earlier in disease progression could significantly improve the treatment of patients. Ex vivo studies with ultra-high field have revealed that diffusion MRI (dMRI) can reveal microstructural variations within the hippocampal subfields and lamina, and may also be sensitive to intra-hippocampal pathways. However, translation to lower resolution in vivo dMRI studies of the hippocampus is challenging due to its complicated geometry. One novel way to overcome some of these obstacles is by transforming the usual Cartesian coordinates in an MRI image to coordinates that are crafted to curve themselves according to the complicated geometry of the hippocampus. This procedure allows us to virtually unfold the hippocampus into a thin sheet. In this work, we introduce an algorithm to map diffusion MRI data to this sheet, allowing us to overcome the difficulties associated with the hippocampus’ complicated geometry. We demonstrate how our method can be readily integrated into existing implementations of traditional tractography methods and how it leads to enhancements in the resulting tracts. Further, our results on high quality in vivo dMRI acquisitions show that unfolding the hippocampus leads to a more anatomically plausible modelling of the connectivity of the hippocampus as probed by probabilistic tractography, revealing key elements of the polysynaptic pathway and anterior-posterior connectivity gradients.

In the present work, hybrid composites were developed by using polyester waste fibers along with natural origin materials: olive root fibers and coir pitch filler. Such composite panels can be used as a potential alternative for fiber glass sunshade panels and room dividers in buildings. Hybrid composites were fabricated by mixing polyester waste fibers and olive root fibers in different ratios (0:100, 33:67, 67:33 and 100:0). Coir pith micro-particles with an average size of 312 d.nm were used as filler in the polyester matrix at three different levels (0%, 5%, and 10%) of the overall matrix weight. Mechanical properties, e.g., tensile strength, flexural strength and impact strength, thermal properties, e.g., coefficient of linear thermal expansion, thermo-gravimetric analysis (TGA) and environmental properties, e.g., water absorption, loss of density after exposure to weathering were characterized. For comparison purposes, a commercially available fiber glass sunshades sample was also investigated. Mixture design analysis was used to optimize the ratio of all components in the composite. Graphical comparison of experimental results using regression models showed a high degree of correlation. An optimized formulation of composite with an objective of maximization of tensile strength, flexural strength, impact strength and minimization of water absorption, density loss, as well as coefficient of linear thermal expansion, was determined at 70.83 wt%, 15.15 wt%, and 14.01 wt% of polyester waste fibers, olive root fibers and coir pith micro-fillers, respectively. Overall, it can be concluded that the developed hybrid composites from waste fibrous materials can be used as a promising alternative and a value-added application in buildings and construction purposes.

The building insulation is one of the needed element or component in building construction; it protects the construction against heat leakage for saving energy. The current research work aims to utilize natural fibers in concrete and develop such type of environmentally friendly material that has better thermal insulation properties. Thermal conductivity test, scanning electronic microscope tomography (SEM) and microscopic images for interfacial bonding of fibers with concrete were performed for plain concrete and natural fibres light weight reinforced concrete (RC) samples. Thermo-gravimetric analysis (TGA) was performed to check the thermal stability of natural fibres RC. The compressive strength was also measured to investigate the mechanical cost at which thermal insulation is achieved. Thermal conductivity results showed that by increasing the percentage of natural fibres (Jute, Coconut, Sugar cane, Sisal, Basalt) in concrete the thermal insulation characteristics increased while compressive strength decreased. TGA indicated that Jute, Sugarcane and Basalt fibres RC have better thermal stability as compared with plain concrete up to 50 °C which is suitable for South Asian countries climate but Sisal and Coconut fibres reinforced samples have comparatively a bit lower thermal stability. However, at 2.5% mixing of coconut and jute we were able to achieve improvement in both compressive strength and thermal insulation.

© 2018 SPIE. Diffusion weighted magnetic resonance imaging (dMRI) has enabled the in vivo imaging of structures with a highly fibrous composition, such as brain white matter due to the ability to detect the hindered and restricted diffusion of water along its defined tracts. In order to increase this non-invasive technique's sensitivity to the intricate fibrous structure and to better calibrate diffusion pulse sequences and validate fibre reconstruction modelling techniques, physical diffusion phantoms have been developed. These phantoms have a known structure and diffusion behaviour. This work aims to simplify the process of creating complex fibre-based diffusion phantoms using 3D printing material to model and mimic brain white matter fiber architecture for dMRI. We make use of a printing material consisting of a mixture of polyvinyl alcohol (PVA) and a rubber-elastomeric polymer (Gel-Lay by Poro-Lay), printed using a fused deposition modelling (FDM) printer. It is 3D printed as a rigid object but, following immersion in room-temperature water, the PVA dissolves away leaving behind the porous rubber-elastomeric polymer component to mimic the structure of brain white matter tracts. To test the validity of the methodology, two preliminary main phantoms were created: a linear 10mm × 10mm × 30mm block phantom and an orthogonal fibercrossing phantom where two blocks cross at a 90-degree angle. This was followed by creating 3 disk phantoms with fibres crossing at 30, 60 and 90 degrees. Results demonstrate reproducible high diffusion anisotropy (FA= 0.56 and 0.60) for the phantoms aligned with the fibre direction for the preliminary linear blocks. With multi-fibre ball & stick modelling in the orthogonal fibre-crossing phantom and the disk phantoms at 30, 60 and 90 degrees, image post-processing yielded crossing fibre populations that reflected the known physical architecture. These preliminary results reveal the potential of 3D-printed phantoms to validate fibre-reconstruction models and optimize acquisition protocols, paving the way for more complex phantoms and the investigation of long-term stability and reproducibility.

In this comparative study, bamboo viscose fibre was studied as an eco-friendly alternative to cotton fibre in polyester-cellulosic blends. Conventional cotton is not considered eco-friendly because it requires large quantities of water and pesticides during its production. The eco-friendly nature of bamboo viscose is subject to the employed production method. Polyester-bamboo (PB) and polyester-cotton (PC) blended yarns were prepared by employing open-end spinning technique and the said yarns were single jersey weft knitted. The yarn tensile strength, fabric bursting strength, bending length, thermal resistance and moisture management properties were studied. The PB blend outperformed the PC blend in terms of mechanical properties and exhibited lower thermal resistance than the PC blend, which is favourable for summer clothing. However, the moisture management properties of PB blended fabrics were found to be similar to those of PC blended fabrics at higher proportions of bamboo viscose fibre in the PB blend.

We model an extreme mass ratio merger (EMR) as a point particle radially plunging into a large Schwarzschild black hole. We assume that the mass of the point particle, $\mu$, is much smaller than the black hole mass M. Under this assumption we can employ the Zerilli formalism modified to include a source term which arises from the energy-momentum tensor of the small object. We solve the Zerilli equation by numerically evolving initial data. Then, we ray trace the null geodesics of the event horizon from after the merger backward in time to extract the geometry of the perturbed event horizon. Further, we take advantage of the axisymmetry of the setup to locate the apparent horizon and study its geometry., Comment: 22 pages, 7 figures

The domain of outer communication of five-dimensional asymptotically flat stationary spacetimes may possess non-trivial 2-cycles (bubbles). Spacetimes containing such 2-cycles can have non-zero energy, angular momenta, and charge even in the absence of horizons. A mass variation formula has been established for spacetimes containing bubbles and possibly a black hole horizon. This `first law of black hole and soliton mechanics' contains new intensive and extensive quantities associated to each 2-cycle. We consider examples of such spacetimes for which we explicitly calculate these quantities and show how regularity is essential for the formulae relating them to hold. We also derive new explicit expressions for the angular momenta and charge for spacetimes containing solitons purely in terms of fluxes supporting the bubbles., Comment: 18 pages, 3 figures

We revisit the problem of perturbations of Schwarzschild-AdS$_4$ black holes by using a combination of the Martel-Poisson formalism for perturbations of four-dimensional spherically symmetric spacetimes and the Kodama-Ishibashi formalism. We clarify the relationship between both formalisms and express the Brown-York-Balasubramanian-Krauss boundary stress-energy tensor, $\bar{T}_{\mu\nu}$, on a finite-$r$ surface purely in terms of the even and odd master functions. Then, on these surfaces we find that the spacelike components of the conservation equation $\bar{\mathcal{D}}^\mu \bar{T}_{\mu\nu} =0$ are equivalent to the wave equations for the master functions. The renormalized stress-energy tensor at the boundary $\displaystyle \frac{r}{L} \lim_{r \rightarrow \infty} \bar{T}_{\mu\nu}$ is calculated directly in terms of the master functions., Comment: 10 pages, RevTeX

The research reports the results and investigations made on 20/1 cotton hosiery yarn and knitted fabric to evaluate the effect of different conditioning methods on the mechanical and comfort properties of yarn and fabric, namely, bursting strength, moisture management, thermal conductivity, air permeability, skewness, stiffness, and pilling. The fibers spun on a ring spinning system were investigated as yarn according to ASTM standards. From the results it is concluded that the knitted fabric made from machine conditioning has better mechanical and comfort properties than fabric made through unconditioned and room conditioned yarns.

The mechanical and comfort properties of polyester/bamboo and polyester/cotton knitted fabrics were studied. Four different ratios, P/B 65/35, P/B 50/50, P/B 35/65, P/B 20/80, P/C 65/35, P/C 50/50, P/C 35/65, P/C 20/80 of both blends were produced by mixing at the blow room stage. Then yarns of equal count Ne 20 were made on a ring spinning machine, and a knitted fabric was produced on a single jersey weft knitting machine. It was observed that by increasing bamboo and cotton fiber content in the blends, yarn breaking force and tenacity were decreased. Bursting strength, bending rigidity, and thermal resistance of the blended fabrics decreased by increasing bamboo and cotton fiber content in the blends, while air permeability and moisture management capability was found to increase with the increase in bamboo and cotton fiber content. No antimicrobial activity was shown by any of the P/B blended fabric, but to some extent, 100% bamboo fiber showed antibacterial activity against gram negative bacteria while against gram positive bacteria, no activity was observed.