The hairiness of worsted wool and cashmere yarns and the impact of fiber curvature on hairiness

In this study, a range of carefully selected wool and cashmere yarns as well as their blends were used to examine the effects of fiber curvature and blend ratio on yarn hairiness. The results indicate that yarns spun from wool fibers with a higher curvature have lower yarn hairiness than yarns spun from similar wool of a lower curvature. For blend yarns made from wool and cashmere of similar diameter, yarn hairiness increases with the increase in the cashmere content in the yarn. This is probably due to the presence of increased proportion of the shorter cashmere fibers in the surface regions of the yarn, leading to increased yarn hairiness. A modified hairiness composition model is used to explain these results and the likely origin of leading and trailing hairs. This model highlights the importance of yarn surface composition on yarn hairiness.<br /

Investigation of yarn hairiness

Yarn hairiness affects not only the quality of products, but also the productivity in spinning and weaving. Too much yarn hairiness is undesirable for many end uses as well as the spinning and post spinning processes. The main aims of this project are to examine the hairiness features of various yarns and to reduce yarn hairiness. The thesis covers five related areas – hairiness assessment, factors affecting yarn hairiness, the hairiness of newly developed yarns, yarn hairiness reduction, and effect of yarn hairiness on the energy consumption in ring spinning. The worsted cashmere, pure wool and wool/cashmere blend yarns were employed to investigate the effect of some fibre parameters on the yarn hairiness. A single exponential distribution of the hair-length was confirmed first, using the data from the Zweigle G565 Hairiness Meter. A linear relationship was observed between the blend ratio and the hairiness indexes. In particular, the effect of fibre crimp or curvature on yarn hairiness is examined. The theory of yarn hairiness composition was also developed further. The effect of draft ratio and spindle speed on the hairiness of worsted wool yarn was examined next with a factorial experiment design. Several new hairiness indexes, namely the relative hairiness indexes, have been used to explain the results obtained. In the investigation of the hairiness of newly developed yarns, the hairiness of the Compact Spun and Roller-Jet-Spun yarns was examined first. The composition of the yarn hairiness, the hair-length distribution, and the effect of test speed on yarn hairiness were then studied. An important finding is that for both yarns, the predominant hairiness feature is the looped hairs. A comparison of the hairiness of Solospun yarns and the equivalent ring spun wool yarns was undertaken. The hair-length distribution of the Solospun yarn was examined first. The Solospun yarns used had fewer hairs in most hair-length groups and lower variations in hairiness. In addition, the effect of twist level and spindle speed on the hairiness of Solospun and conventional ring spun yarns has also been discussed. A novel approach of reducing yarn hairiness – spinning with a ‘Diagonal’ yarn path was examined next. Both ‘Left Diagonal’ and ‘Right Diagonal’ yarn arrangements were studied. A new finding is that the ‘Right Diagonal’ yarn path leads to reduced hairiness for the Z-twist yarn, while yarn evenness and tenacity are not as sensitive to the modified yarn path. The mechanism of hairiness reduction with the ‘Diagonal’ yarn path has been discussed. The spinning performance of “Right Diagonal” yarn arrangement has also been evaluated. Finally, the effect of yarn hairiness on the energy consumption in ring spinning has been investigated theoretically and experimentally. A theoretical model has been developed, which represents the first attempt at theoretically investigating the influence of yarn hairiness on energy consumption during the winding stage of ring spinning. The experimental results have generally confirmed predictions of this model. Recommendations for further research in this area have also been made in the concluding chapter of this thesis

Effect of yarn hairiness on energy consumption in rotating a ring-spun yarn package

The effect of yarn hairiness on energy consumption when rotating a ring-spun yarn package is investigated theoretically and experimentally. A theoretical model is developed to calculate the energy required to rotate hair fibers, based on hair length and number as well as package speed and size. A single spindle test rig is used to verify the theoretical prediction. The experimental results confirm the theoretical prediction that the package power increases with increased yarn hairiness level and spindle speed

Clinical characteristics and lateralization of the horizontal semicircular canal light cupula

IntroductionPositional vertigo and nystagmus are the main symptoms and signs of dizziness, respectively. Despite the clinical utility of the supine roll test (SRT) and null point (NP) in diagnosing light cupula, a type of positional vertigo, there exists a notable gap in the literature concerning the comprehensive evaluation of lateralization values based on various nystagmus characteristics and the intensity of direction-changing positional nystagmus (DCPN) in the SRT, particularly in comparison to the NP. Additionally, limited data on abnormal canal paresis (CP) in light cupula patients underscores the need for further research with a larger patient population to elucidate this mechanism. This study aims to investigate the characteristics of positional nystagmus and lateralization of the horizontal semicircular canal (HSCC) light cupula, which is a type of positional vertigo and nystagmus that is poorly understood.MethodsEighty-five patients (17 males, 68 females; mean age, 60.9 years) with light cupula were reviewed. We summarized the characteristics of spontaneous nystagmus and positional nystagmus, including supine positioning nystagmus, bow nystagmus, and lean nystagmus. Then, the side of the NP was identified as the affected side, and the values of the fast phase direction of the spontaneous nystagmus, supine positioning nystagmus, bow nystagmus, and lean nystagmus, as well as the intensity of the DCPN in the SRT, were used to diagnose the affected sides. Caloric testing was also performed for some patients.ResultsLight cupula was observed in 5.7% of the patients with positional nystagmus. The frequencies of supine positioning nystagmus (88.2%), bow nystagmus (90.6%), and lean nystagmus (83.5%) were higher than spontaneous nystagmus (61.2%) (p &lt; 0.001). The second NP (NP2) (92.9%) and third NP (NP3) (83.5%) were readily detected, affecting the left and right sides in 38 and 47 patients, respectively. Lateralization through the fast phase directions of bow nystagmus and lean nystagmus did not significantly differ from that of NP (all p &gt; 0.05). However, the accuracy rate of lateralization through the sides with more vigorous DCPN in the SRT was 63.5%, significantly lower than through NP (p &lt; 0.001). Particularly in patients with supine positioning nystagmus (n = 75), the rate was only 58.7% (p &lt; 0.001). However, the rate was 100% in patients without supine positioning nystagmus (n = 10). Among the 70 patients who underwent caloric testing, 37 had abnormal CP, and the sides of the reduced caloric reaction were ipsilateral to the affected sides of the light cupula in 83.8% of the patients.ConclusionBesides utilizing the NP to determine the affected side, the fast phase direction of the bow nystagmus or lean nystagmus can also aid in identification. However, a simple comparison of the intensity of DCPN in SRT cannot provide accurate lateralization, especially in patients with supine positioning nystagmus. There is a high incidence of CP on the affected side of the light cupula

Reducing yarn hairiness with a modified yarn path in worsted ring spinning

The spinning geometry of a ring frame plays an important role, and the twist triangle is the critical region in ring spinning. Changes in the spinning geometry may affect yarn properties. This paper examines the idea of ring spinning with a &quot;diagonal&quot; yarn path, and the effect of such a path on yam properties, particularly hairiness. Both &quot;left diagonal&quot; and &quot;right diagonal&quot; yam arrangements are tried on a 24-spindle Cognetex FLC worsted ring frame. The hairiness results obtained from the Zweigle hairiness meter show that the right diagonal yam path produces yams of lower hairiness than the conventional ring spun yarn in almost all the hair length groups. Yam evenness and tenacity are not as sensitive to the change in yarn path. The mean spindle speed at break is also tested, and there is some deterioration in spinning efficiency with the right diagonal yarn path, particularly at higher spinning speeds. Results from this study may help explain variations in yarns spun on poorly aligned ring frames. <br /

Comparing the hairiness of solospun and ring spun worsted yarns

This paper compares the hairiness of Solospun yarns with conventional ring spun worsted yams of the same specifications. A 24-spindles worsted ring spinning frame is used to spin the Solospun and conventional ring spun yarns at the same time, and yarn hairiness is measured. The total hairiness number (Tp), the number of hairs longer than or equal to 3mm (S3), the percentage of longer hairs in total hairs (100S3/Tp), and the total hair length per unit yarn length (K\u27 ) are used to compare the hairiness of these yams. The results indicate that the Solospun yarn exhibits less hairiness in each of the hair length groups and has lower variations in yarn hairiness. The hair-length distribution of the Solospun yarn follows an exponential law just like conventional ring spun yams. There is a statistically significant difference between the Solospun and conventional ring spun yams for T p, S3, and K\u27, but the difference in 1 00S 3/Tp is not statistically significant for these yams. In addition, the Tp, S3, and K\u27 values of the Solospun yarn decrease with twist increase and increase with spindle speed increase, but the 100S3/Tp values of the Solospun and conventional ring spun yarns in this study behave differently in that they are affected by twist level and spindle speed. <br /

CDK1 switches mitotic arrest to apoptosis by phosphorylating Bcl-2/Bax family proteins during treatment with microtubule interfering agents

Microtubule interfering agents (MIAs), that can stabilise or depolymerise microtubules, are an important class of cancer chemotherapeutic drugs. They can lead to mitotic arrest and subsequent apoptosis. We demonstrate that cell cycle-dependent kinase 1 (CDK1) is important in switching cells from mitotic arrest to apoptosis during MIAs treatment. Overexpression of non-degradable cyclin B1 sustained CDK1 activation and mitotic arrest, followed by caspase-3 dependent apoptosis. CDK1 is responsible for the phosphorylation of several pro- and anti-apoptotic Bcl-2 family proteins during MIAs treatment. CDK1-mediated Bcl-2 serine 70 phosphorylation enhances its pro-apoptotic function, whereas CDK1-mediated Bad serine 128 phosphorylation promotes apoptosis. Blockage of CDK1 activity with a specific pharmacological inhibitor suppresses Mcl-1 phosphorylation, degradation and its anti-apoptotic function. Therefore, the death of cancer cells under MIAs treatment was caused by imbalance between CDK1-induced alterations in the pro-apoptotic and anti-apoptotic functions of phosphorylated Bcl-2 family proteins

Polarimetric Calibration and Quality Assessment of the GF-3 Satellite Images

The GaoFen-3 (GF-3) satellite is the first fully polarimetric synthetic aperture radar (SAR) satellite designed for civil use in China. The satellite operates in the C-band and has 12 imaging modes for various applications. Three fully polarimetric SAR (PolSAR) imaging modes are provided with a resolution of up to 8 m. Although polarimetric calibration (PolCAL) of the SAR system is periodically undertaken, there is still some residual distortion in the images. In order to assess the polarimetric accuracy of this satellite and improve the image quality, we analyzed the polarimetric distortion errors and performed a PolCAL experiment based on scattering properties and corner reflectors. The experiment indicates that the GF-3 images can meet the satellite’s polarimetric accuracy requirements, i.e., a channel imbalance of 0.5 dB in amplitude and ±10 degrees in phase and a crosstalk accuracy of −35 dB. However, some images still contain residual polarimetric distortion. The experiment also shows that the residual errors of the GF-3 standard images can be diminished after further PolCAL, with a channel imbalance of 0.26 dB in amplitude and ±0.2 degrees in phase and a crosstalk accuracy of −42 dB