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The analysis of three characters corresponding to different spaces and times shows the close link between literature and the history of medicine. On one hand, Don Quixote of La Mancha, who reflects the thought of the last years of the Renaissance and that has been assimilated in contemporary Mexico. On the other hand, Doctors Miguel Francisco Jiménez and Rita Levi Montalcini, who lived in the 19th and 20th centuries, respectively. Despite the years that separate these three personalities, many elements in common are observed that do not lose their validity: the value that is given to health, ethics, tenacity and experience to attain successful results. All three characters refer to the medicine of their time, their achievements and the promotion of humanism, always inherent to medicine.El análisis de tres personajes correspondientes a espacios y tiempos diferentes muestra el estrecho vínculo entre la literatura y la historia de la medicina. Por un lado, don Quijote de la Mancha, quien refleja el pensamiento de los últimos años del Renacimiento y ha sido asimilado en el México contemporáneo. Por otro lado, los doctores Miguel Francisco Jiménez y Rita Levi Montalcini, quienes vivieron en los siglos XIX y XX, respectivamente. A pesar de los años que separan a los tres personaje, se advierten numerosos elementos en común que no pierden vigencia: el valor que se otorga a la salud, la ética, la tenacidad y la experiencia para obtener resultados exitosos, entre otros. Los tres personajes aluden a la medicina de su tiempo, los logros alcanzados y la promoción del humanismo, siempre inherente a la medicina.

Around the world, people living close to polluting industries have different perceptions of the risks of toxic exposure, ranging from anger to acceptance to denial. We draw attention to a case with relatively high levels of social trust, but also relatively high levels of risk perception: the communities living adjacent to the Fawley (UK) oil refinery and petrochemical complex, a site that has been operated by Esso since the early 1950s. Our findings are based on a novel comparative analysis of two qualitative studies of local risk perceptions in Fawley conducted more than two decades apart in 1997 and 2019, incorporating focus group and individual interviews with residents, alongside documentary analysis and stakeholder interviews. Perceptions of risk and trust in the local polluting industry have fluctuated over the years, with unease never far from the surface as industrial employment has slowly contracted. Yet overall, the picture in 2019 was not too dissimilar from that in 1997: while community–industry relations were strained amidst periodic risk incidents and a sense of decline, a cautious sense of trust in the polluting enterprise had endured, based on a delicate balance of heritage, risk, and recognition. We draw attention to the residents’ careful reckoning with risks over time and the tenacity of social trust as an act of negotiation that took risk into account but also included other important factors such as recognition and reciprocity. Local risk perceptions in Fawley are closely bound up with the residents’ shared industrial heritage and enduring perceptions of Esso as a ‘good neighbour’. Our longitudinal analysis allowed us to reflect on changes over time in Fawley, providing greater temporal depth to the risk perception literature.

The article recalls the big personality of Petru Poni, one of the Romanian pioneers of the research in chemistry. The evocation is realized from the perspective of his contribution in the development of education in the second part of the 19th century as it is reflected mainly in his memoirs �What I wanted to do�. The achievement of the objectives of his life did not have a smooth path. However, his willingness to learn, the choice of action instead of resemnation and the purpose to do something meaningful in his life brought him to accomplishment.

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In this study, Low-velocity impact and residual flexural properties of intraply hybrid epoxy composites reinforced with E-glass, aramid, high tenacity polyester (HTPES), and ultra-high molecular we...

During the Spring semester of 2020, due to a global pandemic caused by the widespread of the novel COVID-19 pandemic, a sudden swift shift to remote instruction radically shook student experiences....

Composite yarns are structures which consist of at least two strands, one forming the central axis or core and other forms wrap. Composite yarn is classified into covered yarn, core spun yarn and wrapping spun yarn. Composite yarns are used for special applications like military apparels, sportswear, sewing thread, protective textiles, etc. Wrap yarn is a composite structure and consists of twisted or twist less core of fibres bound by a continuous filament. Wrap yarn is produced by various methods; most commonly used method is hollow spindle method and ring spinning method. To improve the wrap yarn properties, the yarn is made in ring spinning machinery by making some modifications. It is widely recognized that new technology innovations in ring spinning in the production of wrap yarn will increase the yarn covering ability, yarn tenacity, uniformity, great potential to product versatility, etc. The concentration of this work is to produce cluster wrap yarn using different types of spreading roller retrofitted in the ring frame on the basis of solo spinning technology. The VGWS yarn shows 7 wraps per cm along the length of the yarn, and the wrapping ability of the VGWS yarn is better compared to that of other wrap spun yarns. The results demonstrate that the tenacity and elongation of VGWS are higher than other three yarns. The hairiness, evenness and imperfections per km of VGWS yarn are also better than CWS, LGWS and RGWS wrap spun yarns.

Bamboo is a natural biomass material with excellent properties such as antibacterial and deodorising properties. With the concept of green ecology gaining popularity, bamboo is also being used in a wide range of industries in various forms. With reference to cotton, linen and other plant fibres commonly used in the textile industry today, bamboo is proposed to be made into spun and twisted bamboo fibre bundles through a twisting process and then made into textile bamboo yarns through a certain textile process. The process is divided into three steps: first, the bamboo is delignified, then the bamboo is thinned into bamboo fibre bundles, and finally, the bamboo is twisted into bamboo fibre bundles using home-made equipment. By comparing the chemical composition, mechanical strength and microstructure of the twisted bamboo fibre bundles with those of the original bamboo fibre bundles, the effect of the twisting treatment process on the properties of the bamboo fibre bundles was analysed. The experimental results showed that the tenacity, elongation at break and stiffness of the twisted bamboo fibre bundles were significantly improved compared to the original bamboo fibre bundles. In conclusion, the twisted bamboo fibre bundles have good tenacity and strength and are a potential new material for textile yarns.

Textile filaments were fabricated from a solution obtained from carboxymethylated cellulose dissolved in aqueous NaOH solution, by wet spinning in an acid coagulation bath. Spinning is possible for modified cellulose with a carboxyl group content of at least 1.3 mmol/g cellulose. A post-treatment—heating in the presence of sodium hypophosphite—improved the properties of these filaments. This is a novel process, much more environmentally friendly than the viscose process for the production of rayon, in which most of the chemicals can be reused making it likely that the process is economically viable. After extrusion in an acid bath, filaments containing 1.3 mmol –COOH/g cellulose could be washed with water quite readily, a process very difficult for filaments with carboxyl group content of 1.5–1.7 mmol/g cellulose. The tenacity of the filaments obtained from the modified cellulose with a carboxyl group content of 1.3 mmol/g cellulose was 1.0 cN/dtex, which was higher than that of the filaments with carboxyl group contents of 1.5 mmol/g cellulose (tenacity 0.93 cN/dtex) and 1.7 mmol/g cellulose (tenacity 0.88 cN/dtex). The water absorbency of the filaments made from the modified cellulose with carboxyl group content of 1.3 mmol/g cellulose was 0.54 g water/g filaments which was ~ 2 times and ~ 3.5 times lower than that of the filaments with carboxyl group contents of 1.5 mmol/g cellulose and 1.7 mmol/g cellulose, respectively. The values of tenacity and water absorbency for filaments with 1.3 mmol/g cellulose are extremely promising for textile applications.

Exact description of yarn structure using mathematical formulation leads to complete identification of yarn properties and hence projection of fabric properties. The present work is an attempt trial to study the yarn geometry to find a suitable exponent of twist factor. The logic of analysis is based on the well-known helical model of yarn introducing the variability of raw material and production technology. Different cotton yarns were used to justify the results of the theoretical analysis. The effect of the suggested and other known exponents on the behavior of the strength – twist multiplier curves were compared. Also the values of the constant (k) used in determination of yarn diameter is discussed according to the suggested exponent.

In this study, the fatigue behavior of Engineered Cementitious Composites incorporating high tenacity polypropylene fiber was investigated. The strain curves, cycle numbers, crack numbers and stiffness values were obtained from the experiments carried out with the load-controlled fatigue method at 80, 90 and 110% stress level (maximum stress/ultimate static strength). In conclusion, at 80% stress level, average 1127 cycles, 1.37% the unit deformation capacity and 6 cracks were achieved. At 90% stress level, 215 cycles, 1.89% the unit deformation capacity and 8 cracks were obtained. In the specimens where 110% stress level was applied, the average number of cycles was decreased to 38 cycles, the unit deformation capacity increased up to 2.60% and the average number of cracks also doubled and raised to 15 cracks. Additionally, the average stiffness values of 8.68 and 9.57 GPa were obtained in the first cycles at 80% and 90% stress levels, it was observed that the stiffness values gradually decreased with increasing cycles. Although high strain values were achieved at the 110% stress level, micro cracks were formed suddenly due to the very high applied loading and the rigidity values remained low since the first cycle due to the plastic deformation.

In this paper, biaxial warp-knitted flexible composites (BWFS) were fabricated with high tenacity polyester and PU film. The mechanical properties of the above BWFS samples are tested, including their tensile performance (in 0 °, 45 ° and 90 ° directions), tearing performance (in both 0 ° and 90 ° directions) and stabbing resistance. The results show that the tensile stress firstly decreases and then increases form 0 ° to 90 ° directions and the damage process of composite under uniaxial loading can be divided into three stages. The vertical tearing stress of all BWFS was almost higher than the horizontal tearing stress. In addition, the peak load and deformation displacement of the composites increase with an increase of high tenacity polyester fineness and inserted yarns density in stabbing resistance.

Barite (BaSO4) is a common mineral in sandstone that must be removed during separation of detrital zircon (ZrSiO4). One widespread technique for the removal of barite exploits its lesser tenacity by milling the barite and zircon mixture in a ball mill. Here we test the extent to which such milling affects zircon and thus whether the milling could introduce bias into the detrital zircon sample. We then describe a new chemical technique for the removal of barite from detrital zircon. We find that milling a mixture of barite and zircon both breaks and causes loss of zircon grains, potentially introducing bias into a detrital zircon sample. Boiling barite in a 0.94 molar aqueous solution of sodium carbonate for 4 h converts most grains to barium carbonate. The barium carbonate grains are opaque white and thus visually distinguishable from zircon, allowing separation by hand under a stereoscopic microscope. Alternatively, the barium carbonate grains can be dissolved by boiling in 16 wt% nitric acid for 30 min. In our experiments, boiling zircon in sodium carbonate solution and/or concentrated (65 wt%) nitric acid cleaned the surfaces of and the cracks in the grains but did not visibly change the zircon surfaces in other ways. Boiling only in concentrated nitric acid did not measurably affect the U-Pb and Lu-Hf isotopic systems in zircon interiors, and boiling in a sodium carbonate solution followed by concentrated nitric acid did not detectably alter the Lu-Hf isotopic system. However, boiling in a concentrated sodium carbonate solution followed by concentrated nitric acid did disturb the U-Pb isotopic system in zircon interiors. We recognize this disturbance due to a ~0.5% reduction in 206Pb/238U dates of treated zircon. Our results highlight the importance of proper technique during zircon isolation to minimize the introduction of bias into the sample.

Poly(lactic acid) (PLA) is an attractive biomaterial due to its biocompatibility, biodegradability, and fiber-forming ability. However, the polymer is highly susceptible to both hydrolytic and thermal degradation during processing. Melt processing conditions typically involve high temperature and shear, whereas to prevent premature degradation, PLA needs to be processed under the mildest conditions that still yield the desired yarn properties. Thus, there is a need to determine the optimum processing conditions to achieve the desired properties of extruded PLA yarn. This study focuses on the effect of melt-spinning process parameters on the mechanical and physicochemical properties of the resulting PLA yarn and to derive their process-property relationships. The study compares the effect of process parameters like melt temperature, throughput through the spinneret, take-up speed at the wind-up roller, draw ratio, and drawing temperature on the yarn properties such as the yarn size (linear mass density), tenacity, elongation at break, crystallinity, and molecular weight. Depending on the combination of process parameters, the resulting PLA yarn had a yarn size ranging from 6.2 to 101.6 tex, tenacity ranging from 2.5 to 34.1 gf/tex, elongation at break ranging from 4 to 480%, and degree of crystallinity ranging from 14.6 to 62.2%. Certain combinations of processing parameters resulted in higher process-induced degradation, as evident from the reduction in molecular weight, ranging from 7.6% reduction to 20.5% reduction. Findings from this study increase our understanding on how different process parameters can be utilized to achieve the desired properties of the as-spun and drawn PLA yarn while controlling process-induced premature degradation.

W umiarkowanym okresie swojej twórczości Feyerabend utrzymywał, że wzajemne oddziaływanie zasad proliferacji i uporczywości może przyspieszać pożyteczne biologicznie mutacje oraz może być jedynym dostępnym środkiem służącym do zapobiegania stagnacji naszego gatunku. Celem tego artykułu jest rekonstrukcja poglądów Feyerabenda na to zagadnienie oraz nadanie im określonej interpretacji, pozwalającej uniknąć pewnych problemów, do których te poglądy prowadzą. Przekonanie, że można przyspieszać biologicznie pożyteczne mutacje za pomocą formułowania i bronienia hipotez, sugeruje, przynajmniej na pierwszy rzut oka, podejście lamarkistowskie - teorię zmienności ukierunkowanej. Tę myśl Feyerabenda da się również rozumieć w duchu teorii zmienności nieukierunkowanej, a więc na modłę darwinowską, co sugeruje wyrażenie "może przyspieszać". Obydwa ujęcia prowadzą jednak do poważnych trudności. Lamarkistowskie uważane jest obecnie za błędne, zaś zgodnie z darwinowskim zmiany adaptacyjne zachodzą bardzo powoli. Biologicznie pożyteczne efekty współdziałania proliferacji i uporczywości pojawić się mogą po niesłychanie długim okresie czasu. Jego myśl, że wzajemne oddziaływanie proliferacji i uporczywości może być jedynym dostępnym środkiem zapobiegania stagnacji naszego gatunku najlepiej jest rozumieć w duchu kulturowej ewolucji człowieka, która ma charakter lamarkistowski.

In this paper, biaxial warp-knitted fabrics were produced with different high tenacity polyester linear density and inserted yarns density. The low-velocity impact property of flexible composites made of polyurethane as matrix and biaxial warp-knitted fabric as reinforcement has been investigated. The effect of impactor shape and initial impact energy on the impact response of flexible composite is tested. The results show that the initial impact energy have minor effect on the impact response of the biaxial warp-knitted flexible composites. The impact resistance of flexible composite specimen increases with the increase of high tenacity polyester linear density and inserted yarns density. The damage morphology of flexible composite materials is completely different under different impactor shapes. The findings have theoretical and practical significance for the applications of biaxial warp-knitted flexible composite.

The main goals of this study were to determine the effect of three yarn structural factors (yarn count, cross section and spandex ratio) and their interactions on tensile and breaking extension properties tensile behavior effect of spandex/polyester spun yarns respective on woven fabrics. Moreover, stress-strain curves were plotted and the yield points and breaking points and their corresponding properties (toughness, stiffness and Initial Young Modulus) were derived. The association between tensile and elongation parameters for spandex/polyester yarn and their woven fabrics was computed using simple correlation coefficient, results explained that all tensile and breaking extension properties significantly increased as the yarn count increased while the effect of cross section was weak or marginal. It is obvious that yield strain, yield stress, breaking extension, breaking tenacity decreased as a result of increasing the spandex content but the decrease percents (%) were generally weak. With respect to the 1st and 2nd order interaction effects, they were no significant for most tenacity and elongation properties of spandex/polyester spun yarns and their respective woven fabrics. The current study appeared that using spandex/polyester spun yarns with lowest spandex content gave the best tensile and breaking extension properties of spandex/polyester spun yarns and their respective woven fabrics. The correlation coefficients between tensile and elongation parameters for spandex/polyester yarn and their corresponding woven fabrics were positive and highly significant (except Initial Young's modulus) indicating that the tensile and breaking extension properties of the spandex/polyester yarns could be used as good indicators for the strength and elongation of fabrics manufactured by these spandex/polyester yarns.

This work presents an emperical formula of plied yarn strength produced from ring spun cotton yams. Experiments carried out on several samples of cotton fibres and the investigation concerned with the influence of fibre properties, single twist, ply twist and number of plies and spinning quality. The results obtained with this formula agree satisfactonly with the experimental data.

A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, this study was focused on investigating the properties of the extracted canola (HYREAR 3) fibers from 3 different diameter of stems (narrow, medium and wide). The physical (average length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of fibers were measured. ANOVA showed that stem diameter had effects on all fiber properties except for average length and elongation at break. Fiber diameter also had significant effects on load at break, elongation at break, aspect ratio, tensile stress, and young’s modulus. In corrgram, it was found that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were positively associated. Mean values showed that stem diameter had effects on all fiber properties except for average length. The mean values of fiber diameter, load at break, elongation at break, tenacity, and contact angle were highest and the lowest mean values were observed for tensile stress, young’s modulus and aspect ratio in fibers of 7 - 10 mm stems (medium matured), hence found to be less stiff. Moisture regain ability showed that canola fibers isolated from ≥8 mm stem diameter were more hydrophobic whereas contact angle measurement showed relatively more hydrophobic nature of 7 - 10 mm stem fibers. Therefore, this study provided an insightful understanding of the quality of the canola fibers of different stems which will ultimately help to choose the best stem to extract different qualities of fibers for commercial uses.

Chemical softener (Cepreton UN) is used to soften the cellulosic fiber (cotton) in the textile industries to make clothes better to touch. Therefore, this study investigated the effects of Cepreton UN on both physical (length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of the lignocellulosic canola (HYREAR 3) fibers extracted from narrow, medium, and wide stems. ANOVA showed that fiber diameter had strong effects on elongation at break, load at break, tensile stress, young’s modulus, and aspect ratio for all fibers. Corrgram values showed that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were mostly positively correlated to fiber diameter. The fibers were treated with 2% and 10% Cepreton UN and compared with control fibers. In most cases, the fiber diameter was decreased in both 2% and 10% treated medium stem fibers. The mean values of elongation at break, load at break, tenacity, and contact angle were decreased for 10% and increased for 2% and the mean values of tensile stress, young’s modulus, and aspect ratio were decreased for 2% and increased for 10% treated medium stem fibers. Moisture regain (%) mostly decreased for 2%, and increased for 10% treated fibers. Low pH (4.5) had an almost similar effect on fibers as 2% Cepreton UN. Overall, 2% Cepreton UN treatment is found to be better than 10% to make canola fibers less stiff and low pH was found to be an alternative softener treatment strategy.

A statistical work was performed to investigate effect of air jet texturing process parameters on acrylic filament yarn properties. It was shown that process parameters such as air pressure, overfe...

Mechanical characteristics of the laminated composite crafted from fabric type reinforcement perhaps inspired via the weaving method and reinforcement agent's usage due to each layer's constructional parameter. As a result, research on the arrangement configuration between bio composite and synthetic fibre for the material shape was proposed to enhance the composite structure's biodiversity and physical characteristics. Substitute for natural fibre in synthetic fibre composite works has shown the excessive capacity to be explored scientifically. The evaluation focused on the concept and essential of bio composite and the synthetic composite fabric positioned over the years from the previous studies of the preliminary researches. The sorts and features of matrix and fibre filler reinforcement materials in composites were also discussed. This assessment's main findings indicated that the composite centre relied on the weave styles and inter-ply and interplay lamination roles. Therefore, the state-of-the-art intraply for synthetic fibre and bio composite fibre in a composite shape was anticipated performing higher in mechanical energy, particularly within the application of ballistic resistance, besides decreased dependency on artificial fibre. It would ultimately suggest the excellent weave sample designs in the proper combination shape of natural and synthetic fibres embedded with polymers. The statistical results were compared with the experimental parameters available inside the literature review. The review explains approximately the studies and evolution within the enhancement of characteristic fibres reinforced polymer composites in ballistic resistance use. This paper goes over the body armour's profitable and present advancement materials, structure and development procedures, and related works on upgrading ballistic energy captivation and upgrading the mechanical tenacity for high impact resistance applications.

Jeankempite, Ca5(AsO4)2(AsO3OH)2(H2O)7, is a new mineral species (IMA2018-090) discovered amongst coatings of arsenate minerals on oxidised copper arsenides from the Mohawk No. 2 mine, Mohawk, Keweenaw County, Michigan, USA. The new mineral occurs as lamellar bundles of colourless to white plates up to 1 mm wide and is visually indistinguishable from guérinite, with which it forms intergrowths. Jeankempite is transparent to translucent with a waxy lustre and white streak, is non-fluorescent under longwave and shortwave ultraviolet illumination, has a Mohs hardness of ~1.5 and brittle tenacity with uneven fracture. Crystals are flattened on {01$\bar{1}$} and exhibit perfect cleavage on {01$\bar{1}$}. Optically, jeankempite is biaxial (+), α = 1.601(2), β = 1.607(2), γ = 1.619(2) (white light); 2Vmeas.= 72(2)° and 2Vcalc.= 71.0°. The empirical formula is (Ca4.97Na0.013Mg0.017)(As3.99S0.01)4O23H16, based on 23 O and 16 H atoms per formula unit. Thermogravimetric analysis indicates that jeankempite undergoes four weight losses totalling 16.82%, close to the expected loss of 16.30%, corresponding to eight H2O. Jeankempite is triclinic,P$\bar{1}$,a= 6.710(6),b= 14.901(14),c= 15.940(15) Å, α = 73.583(12)°, β = 81.984(12)°, γ=82.754(12)°,V= 1507(2) Å3andZ= 3. The final structure was refined toR1= 0.0591 for 2781 reflections withIobs> 3σI. The crystal structure of jeankempite is built from a network of edge- and vertex-sharing CaO6, CaO7and AsO4polyhedra, and we hypothesise that the new mineral has formed due to a topotactic reaction brought on by dehydration of preexisting guérinite.

PurposeOccurrence of fabric rupture is a problem that can influence fabric performance during wear. In this regard, fabric tearing resistance is considered by manufacturers and consumers and enhancing tear resistance through optimization of related parameters is beneficial.Design/methodology/approachIn this study, the tearing resistance of a series of shirting fabrics with various weave patterns and weft densities were investigated by both static and dynamic tear test methods. Moreover, the constituent yarn's frictional and tensile behaviour was evaluated and their relation with tear resistance was analysis.FindingsAccording to the outcomes, the fabric firmness and density and friction of yarns affect the tear resistance, reversely. However an improvement in yarn's tenacity can raise the tear resistance.Originality/valueIn this study it was aimed to not only consider influence of both static and dynamic tear test approach on the tearing performance of fabrics regarding their structural parameters, the impact of the constituent's yarn properties include tensile behaviour and friction coefficient on the tearing performance of fabric considered, as well.

The development of tenacity photoluminescent (PL) hydrogels is very great significance to promote the application of optical technology in hydrogel. Herein, we report a high-toughness PL hydrogel that combines synthetic hydrophilic lanthanide complex (LCs) and tannic acid (TA) with polyvinyl alcohol (PVA) by frozen-thawing. The resulting hydrogel has high mechanical strength (1194.46-kPa tensile strength, 1266.17-kJ m−3 toughness energy, 1915.58-kPa compressive strength, and 269.79-kJ m−3 energy dissipation at 80% compression), excellent self-recover and anti-fatigue performance, good photoluminescence, and switchable functions under UV light, showing red (254 nm) and green (365 nm), respectively. The design strategy offers a new approach for the preparation of multifunctional and tenacity PL hydrogels.

No American playwright-scenarist-director has been so consistently obsessed with the meaning of masculinity than David Mamet. No writer of his stature has attempted with such tenacity to tie the gender-specific eruption of predatory aggressiveness to the commonplace operations of American business. In a series of works that began with American Buffalo, House of Games and Speed-the-Plow and reached a certain culmination with Oleanna, Mamet has addressed with exceptional savagery how contemporary men have negotiated the economic and social minefield that the relentless pursuit of profit and the egalitarian demands of women have registered. The films that he wrote and directed explore these phenomena by also recording the vernacular at its most corrosive pitch.

Technology for the transformation of waste feathers to quality regenerated filaments has been developed. Regardless of superior properties of natural keratin materials, previously developed regenerated materials from keratin had tensile properties much lower than their natural counterparts due to backbone hydrolysis and inefficient reconstruction of disulfide crosslinkages. In this work, tough keratin filaments have been regenerated from white duck feathers via efficient restoration of disulfide crosslinkages using a dithiol reducing agent. Dithiol substantially reserves free thiol groups in the extraction and formed lengthy intermolecular crosslinkages in regenerated keratin filaments. Due to the high degree of intermolecular reconstruction of disulfide bonds and formation of lengthy crosslinkages via dithiol chain-extension, the keratin filaments exhibited considerable improvements in mechanical properties, especially for ductility and water stability. The tenacity and elongation at break were 160.7 MPa and 14%, respectively. The filaments retained about 80% of the tenacity of natural feathers at either dry or wet conditions and demonstrated stretchability 150% higher than natural feathers. The fiber regeneration technology makes it possible to substitute primary fiber sources by renewable poultry feathers. Successful filament substitution or addition can bring more than 88-billion-dollar revenue. The technology not only contributes to a sustainable fiber and poultry industry but adds substantial values to poultry feathers.

The events that followed the revolution of 25 January 2011 demonstrated the tenacity and resilience of gendered dissent and its centrality to collective action and civil disobedience, thus enriching the transnational feminist archive with the experiences and praxis of gendered revolutionary action. Paying particular attention to women’s activism during the uprisings in Egypt, this article focuses on the broader themes of gendered political resistance and the intersections of gender ideology, state policing, Islamism and militarism with protest and collective action. The aim is to take count of the challenges and gains of gendered resistance and women’s political participation during times of political upheaval.

This paper aims to identify the creep mechanisms of high tenacity (HT) polyester industrial fiber under different loads. In-situ synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) tests were conducted on a 1000 D HT fiber during the creep and creep recovery process with a low load (15 N) and a medium load (50 N) as well as creep rupture process with a high load (60 N). The measured creep strain-time curves comprised tensile zone (I), creep deformation zone (II) and creep recovery/rupture zone (III). The SAXS indicated that the macroscopic initial creep strain in zone I and creep deformations in zone II were attributed to conformation transition from gauche to trans in amorphous region, increasing the amorphous orientation and long period. Irreversible portion of conformation changes accounts for the small unrecoverable plastic creep strain after removing 15 N load in zone III. The initial creep strain in zone I and creep deformations in zone II of the 50 N creep process were bigger than the microscopic long period strain, because amorphous layers had conformational transformation and microfibril slippage which also produced a higher unrecoverable plastic creep strain in zone III. The long period increased significantly at the beginning of rupture zone with 60 N due to fragmentation of amorphous tie molecular. The disappearance of lamellar peaks at the end of rupture zone implied destruction of periodic lamellar structures, for the entire breakage of amorphous chains. The WAXS suggested that the crystal structure was stable under the creep loads.

Ultra-high molecular weight polyethylene fibre is popularly used in military for ballistic protection owing to its low density but high modulus and high tenacity. However, the inter-yarn friction in the corresponding ballistic fabric is too low and thus the yarns in the fabric are easily pulled out, in which lowers down the ballistic performance. This paper aims to improve the inter-yarn friction in the fabric by sol-gel method using TiO2/ZnO hydro-sols and investigate the ballistic performance of fabric treated. The results from the coefficient of friction test have showed that the inter-yarn friction treated with TiO2/ZnO hydro-sol can be increased 40%. Moreover, tensile test indicates that the tenacities of yarns after different treatments are increased whereas the strains and moduli of the yarns almost kept unaffected. Through ballistic performance test, the treated fabric displays higher ballistic energy absorption compared with the original one, indicating that higher inter-yarn friction is beneficial to fabric against ballistic impact.

Desde la llegada del cine a Colombia no todo el camino ha sido fácil. Los primeros cineastas se vieron en situaciones económicas complejas que en numerosas ocasiones incluso pusieron en riesgo la continuidad de la actividad cinematográfica en este país. Todo un entramado de ayudas económicas, fiscales y de propaganda por parte del Estado colombiano, así como un extenso cuerpo legislativo, además del tesón de los directores, productores y realizadores de cine en Colombia, van a llevar esta actividad a convertirse en lo que hoy podemos considerar como una verdadera industria.

Stinging nettle (Girardinia diversifolia) is a cellulosic plant fiber which is abundantly available in the upper regions of Himalayas. The stem fibres are pliable which are used to weave or knit fabric. This fiber is very strong, but rigid and inextensible. This has restricted its usage in handmade textile products only. In order to process this fiber on a range of textile machines for development of a variety of products with enhanced performance, the fiber needs to be strong, flexible and extensible. This study was aimed at to increase the fiber tenacity by giving chemical pre-treatment. The effects of various experimental parameters, such as chemical concentration and time on tenacity of nettle fibres were studied. In the study, the chemical pre-treated nettle fibers were examined for their mechanical characteristics and compared to untreated fibers (control sample). The untreated fiber was less flexible and less extensible. A pre-treatment resulted in increase in tenacity and elongation at break. The increase in tensile strength was found to be 5.46 g/den from 3.84 g/den (as in case of control sample) and elongation increased to 3.33% from 1.66%.

PurposeThe purpose of this study is twofold: (1) to examine the relationship between comprehensive social competence, entrepreneurial tenacity and social entrepreneurial action and (2) to test the mediating role of entrepreneurial tenacity in the relationship between comprehensive social competence and social entrepreneurial action among social ventures in Uganda.Design/methodology/approachThe study is cross-sectional and quantitative. Data were analyzed with the help of Statistical Package for Social Sciences and analysis of moment structures.FindingsResults show that both comprehensive social competence and entrepreneurial tenacity are significantly associated with social entrepreneurial action. Results further indicate that entrepreneurial tenacity partially mediates the relationship between comprehensive social competence and social entrepreneurial action.Originality/valueTo the authors' knowledge, this study provides initial empirical evidence on the relationship between comprehensive social competence, entrepreneurial tenacity and social entrepreneurial action using evidence from a developing African country – Uganda. Mostly, this provides an initial evidence of the mediating role of entrepreneurial tenacity on the relationship between comprehensive social competence and social entrepreneurial action.

본 연구는 태권도 시범선수의 팀 응집력, 승부근성 및 인지된 경기력의 관계를 규명함으로써 선수의 경기력을 향상시킬 수 있는 기초자료를 제공하는 데 목적이 있다. 연구목적을 달성하기 위해 2019년 7월 26일부터 7월 30일까지 열린 2019평창세계태권도한마당대회에 참가한 대학교 시범선수 457명의 설문지를 최종자료로 채택한 후 PASW/WIN 21.0 프로그램을 이용하여 빈도분석, 탐색적요인분석, 신뢰도분석, 상관관계분석, 다중회귀분석을 실시하여 다음의 결과를 얻었다. 첫째, 팀 응집력은 승부근성에 정(+)적인 영향을 미치는 것으로 나타났다. 둘째, 팀 응집력은 인지된 경기력에 부분적으로 정(+)적인 영향을 미치는 것으로 나타났다. 셋째, 승부근성은 인지된 경기력에 부분적으로 정(+)적인 영향을 미치는 것으로 나타났다. 이에 따라 태권도 시범선수의 팀 응집력은 승부근성에 긍정적 영향을 미치며, 응집력과 승부근성은 경기력에 부분적으로 긍정적 영향을 미치고 있다는 결론을 얻었다. 따라서 팀의 목표 달성을 위한 시범선수들 간의 효과적인 응집력 강화 훈련방법과 훈련환경조성에 힘쓰는 한편 평소 선수의 승부근성을 파악하고 경기력 향상에 효과적인 심리기술훈련 프로그램을 개발하여 적용한다면 경기에서 좋은 성과를 기대할 수 있을 것으로 사료된다.

Adanite, Pb2(Te4+O3)(SO4), is a new oxidation-zone mineral from the North Star mine, Tintic district, Juab County, Utah, and from Tombstone, Cochise County, Arizona, USA. The characterization of the species is based principally on North-Star holotype material. Crystals are beige wedge-shaped blades, up to about 1 mm in length, in cockscomb intergrowths. The mineral is transparent with adamantine luster, white streak, Mohs hardness 2½, brittle tenacity, conchoidal fracture, and no cleavage. The calculated density is 6.385 g/cm3. Adanite is biaxial (–), with α = 1.90(1), β = 2.04(calc), γ = 2.08(calc), 2V(meas) = 54(1)°. The Raman spectrum is consistent with the presence of tellurite and sulfate groups and the absence of OH and H2O. Electron-microprobe analyses gave the empirical formula Pb1.89Sb3+0.02Te4+0.98S6+1.04Cl0.02O6.98. The mineral is monoclinic, space group P21/n, with a = 7.3830(3), b = 10.7545(5), c = 9.3517(7) Å, β = 111.500(8)°, V = 690.86(7) Å3, and Z = 4. The four strongest X-ray powder diffraction lines are [dobs Å(I)(hkl)]: 6.744(47), 3.454(80), 3.301(100), and 3.048(73). The structure (R1 = 0.022 for 1906 I > 2σI reflections) contains Te4+O3 pyramids that are joined by short (strong) Pb–O bonds to form sheets. Interlayer SO4 groups link the sheets via long Pb–O and Te–O bonds.

The growing importance of fiber blends in apparels are due to many reasons such as it will be cost effective by blending them with other fibers that produce fabrics with a better combination of performance characteristics in the product. The aim of the blends are reduce economic and enhanced the durability, physical properties, colour and appearance. To produce fabrics with a better combination of performance characteristics in the product and to obtain beter hand on fabric appearance and colour dyed effect Hence the present work has been undertaken with an aim to blend the Hibiscus Cannabinus with Ramie for value added products. Different blending ratios were followed such as Kenaf: Ramie 75:25, 50:50 and 25:75 to produce different blended yarns as well as fabrics. Ramie yarn showed highest tenacity (20.87g/tex) while lowest tenacity was observed in controlled Kenaf (13.09g/tex). In case of blended yarn, maximum tenacity was seen in (25:75) kenaf: ramie (16.18g/tex).Plain weave structure fabrics was prepared from the controlled and blended yarns.

The increasing amount of plastic wastes has become a threat to the sustainability of all ecosystem in this Earth. This paper aims to provide an alternative utilization of plastic wastes as the raw material in the manufacturing process of woven bag products with a quality control in its tenacity. The initial phase of this research is a literature review on the concept of green manufacturing, woven bag quality, compositions of plastic wastes and woven bag manufacturing proses. Furthermore, it is followed by a data measurement in a form of tenacity test using a thread test gauge (tenacity). There are two types of the condition in the manufacturing process of woven bag production compared by increasing the temperature as much as 10°C in all the extraction machines. The measurement result shows that the average tensile strength in the production process of the woven bag made from the wastes of mineral water plastic cups with 10% composition and extraction temperature for the first condition is 3.38 g per 1 denier and the second condition is 4.76 g per 1 denier. The result of second condition manufacturing (increasing the extraction temperature by 10°C) after comparing it with the quality required by Standard National Indonesia (SNI) as much as 4 to 6 g per 1 denier is considered good quality. Therefore, through the concept of green manufacturing, the utilization of plastic wastes might provide a substitution to the part of plastic core raw material in the woven bag production. This research is designed to be the beginning of innovation to acquire raw materials for the woven bag, furthermore, the optimization toward the machine setting and innovation on plastic wastes raw materials become the foundation in increasing the tenacity.

In this research work, the authors have investigated the influence of fibre orientation on thickness and tenacity of needle-punched nonwoven fabrics by using three-factor three-level Box–Behnken Design. Three carding parameters such as feeder speed, cylinder speed and doffer speed, which are primarily responsible for fibre orientation, were considered as three factors with three different levels. Fibre orientation was evaluated in terms of anisotropy by using tracer fibre technique. Anisotropy was measured in both un-punched and punched fibrous structure. Tenacity was measured in both machine and cross directions. It was found that the tenacity in the cross direction and thickness decreases but the tenacity in the machine direction increases with the increase of anisotropy as well as fibre orientation.

The new mineral pseudomeisserite-(NH4) (IMA2018-166), (NH4,K)2Na4[(UO2)2(SO4)5]⋅4H2O, was found in the Blue Lizard mine, San Juan County, Utah, USA, where it occurs as light yellow prisms in a secondary assemblage with belakovskiite, blödite, changoite, ferrinatrite, gypsum, ivsite, metavoltine and tamarugite. The streak is very pale yellow and the fluorescence is bright lime green under 405 nm ultraviolet light. Crystals are transparent with vitreous lustre. The tenacity is brittle, the Mohs hardness is 2½, the fracture is curved or conchoidal and there is one perfect cleavage on {100}. The mineral is easily soluble in H2O and has a measured density of 3.22(2) g⋅cm–3. Pseudomeisserite-(NH4) is optically biaxial (–) with α = 1.536(2), β = 1.559(2) and γ = 1.565(2) (white light); 2Vmeas. = 53(1)°; dispersion is r > v, distinct; pleochroism: X colourless, Y light yellow and Z pale yellow (X < Z < Y); optical orientation: Z = b, Y ∧ c = 33° in obtuse β). Electron microprobe analyses (WDS mode) provided (NH4)1.49K0.60Na3.87U2.00S5.04O28H7.78. The five strongest X-ray powder diffraction lines are [dobs, Å(I)(hkl)]: 12.69(76)(100), 6.83(84)(012,102), 6.01(100)($\bar{2}$02), 3.959(67)($\bar{2}$21,$\bar{2}$14,$\bar{1}$23) and 3.135(76)($\bar{2}$06,223,$\bar{1}$16). Pseudomeisserite-(NH4) is monoclinic, P21/c, a = 13.1010(3), b = 10.0948(2), c = 19.4945(14) Å, β = 104.285(7)°, V = 2498.5(2) Å3 and Z = 4. The structural unit in the structure (R1 = 0.0254 for 3837 I > 2σI reflections) is a novel [(UO2)2(SO4)5]6– uranyl-sulfate band.