High-quality Silk Research Articles

Life cycle assessment of Indian silk

Abstract The environmental impact of textiles is an area of increasing interest for consumers and legislators. Life cycle assessment (LCA) is the commonly used decision support tool for quantifying environmental impacts, and has been applied to most all major textiles. So far there has, however, been no cradle-to-gate assessment of raw silk production. On the basis of a review of literature on silk production, this paper constructs a first life cycle inventory of the production of high-quality silk under tropical conditions in southern India. Values are calculated for the following environmental impact indicators: global warming potential, ecotoxicity, freshwater eutrophication, land occupation, cumulative energy demand and blue water footprint. The functional unit is defined as 1 kg raw silk, at factory gate. The analysis compares best practice recommendations with observed farm practices. Where applicable, data gaps have been highlighted. Results indicate that silk production following recommended practices is input intensive and that on a mass basis, environmental impacts are above those reported for other natural fibres. The majority of environmental impacts stem from cocoon production, in particular fertilization. Farm practices diverge from recommendations significantly and the observed impact per functional unit is higher. The multiple stages required to manufacture raw silk result in a large amount of co-products. Increasing the efficiency in utilisation of these could reduce the high impact observed in this study.

Silk dissolution and regeneration at the nanofibril scale.

Native silk features strong, extensible and tough properties which originate from its hierarchical nanofibril structure. In the present study, native silk nanofibrils were obtained by dissolving degummed silk in salt-formic acid (FA), such as CaCl2-FA. The CaCl2-FA dissolved silk by breaking hydrogen bonds in the crystalline region while preserving the nanofibril structures. The dissolution behavior of silk from fibre to nanofibril was determined by Na2CO3 concentration during the degumming process, and was regulated by CaCl2 concentration during the dissolution process. The resulting solution containing silk fibroin (SF) nanofibrils could be easily processed into films with nanofibrous structures and high strength. In addition, high-quality electrospun SF nanofibres could also be generated easily from this solution. The novel dissolution and regeneration behavior of silk at the nanofibril scale provides new insights into methods for the preparation of high-quality silk materials for application in high-tech areas.

Nondestructive gender identification of silkworm cocoons using X-ray imaging with multivariate data analysis

A rapid, reliable and nondestructive method for the gender discrimination of silkworm cocoons is of great importance for the production of high-quality silk by the mulberry silkworm industry.

近代における優等糸生産の展開と製糸技術

近代における優等糸生産の展開と製糸技術

조선시대 銀 유통과 소비문화

The influx of Japanese silver had increased since around 1538, reached its height in the late 17th century, then decreased from the turn of the century, and ceased in around 1753. Most of silver in Joseon[朝鮮] Korea including domestically produced silver as well as that from Japan was used for the import from China, mostly silk products. The massive influx of Japanese silver made silver function as a currency since the 17th century. However, their function as a currency withered as the inflow of silver from Japan fell sharply during the early 18th century. Before port-opening to Western countries[開港], Korea’s silver trade has not encountered with any other countries except Japan and China. Therefore, world system approach is not necessary to understand the silver circulation in Korea. Locked in the Malthus trap, ordinary people in the Joseon dynasty barely managed their life by consuming some necessity goods at most. Only the rich enjoyed their luxury consumption. During the Joseon dynasty the custom of luxury consumption diffused, but part of those newly entered into the middle class went bankrupt due to indulgence and high consumption. The increasing silver influx enriched consumption pattern in Korea by stimulating market and economic growth, and providing the means of trade with China for luxury goods. Leaded by some elites[士大夫], high and refined consumption behaviors became diffused. The sharp reduction of silver influx in the 18th century did not shrink the luxury consumption, because the growth of market and production partly driven by silver trade had a solid foundation. However, the circulation of silver money did not last owing to the efflux of silver, and Korea could not foster the import substitution industry of high quality silk. This is a reason why the economy could not advance in the 19th century before the port-opening. The main discourse about consumption in the Joseon dynasty was respect for frugality and worry about extravagance. Luxury culture in Korea was modest compared with previous dynasties or its neighboring countries. But their attitude toward luxury culture was very negative due to Confucianism. This can explain why Yeonsangun[燕山君], who was not bounded by Confucian teaching, was the only king pushing ahead with an effective substitution policy of high quality Chinese silk. The banning of Chinese silk of high quality[紗羅綾緞] and precious metals[金銀珠玉] that has been frequently practiced until the reign of Jungjong[中宗] became infrequent after the middle 16th century when luxury consumption diffused, because such consumption behaviors were already rooted in the society. A scholar group to study how to increase wealth and welfare [利用厚生學派], emerged in the late 18th century, discussed how to elevate the standard of living and defended high and refined consumption culture beyond the discourse making a sharp distinction between frugality and extravagance.

Defense role of the cocoon in the silk worm Bombyx mori L.

Silk from the domesticated silk worm Bombyx mori procures foreign body response naturally, so it has been utilized as a biomaterial for decades. In India the prime focus of the sericulture industry is to improve silk production with high quality silk. Naturally, the silk worm builds its cocoon not only with silk proteins, but also with antimicrobial proteins to avoid infection since the cocoon is non-motile and non-feeding. The aim of the present study is to elucidate the antimicrobial proteins that persist in the cocoon of the silk worm Bombyx mori. At the pupal stage, the silk worm cocoon shell extract was prepared from the day of pupation (P0) to the day of natural rupture of the cocoon for the eclosion of moth (NR). Using the cocoon shell extract a microbial susceptibility test was performed by the disc diffusion method against the microbes Escherchia coli, Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The development of a zone of inhibition against the microbes confirmed the presence of antimicrobial/immunogenic activity of the cocoon shell extract. For further analysis, the cocoon shell extract was subjected to 7-15% sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE). The protein profile of the cocoon extract revealed the coomassie blue stained bands resolved from the 150-15 kDa molecular range. Interestingly, a polypeptide localized at around 29 kDa showed remarkable expressional changes during the development of pupa. To characterize the 29 kDa protein, it was eluted from the gel, digested with trypsin and analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The trypsin-digested peptide peaks were analyzed through MASCOT and peptides were matched with the NCBI nr database. The peptides were very well matched with the 18 wheeler protein, which is reported to be responsible for innate immunity, belonging to the Toll family in insects and responsible for cellular mediated immunity.

製糸業における採用管理の形成

Gunze Silk Mfg. Co., Ltd. was established in Kyoto prefecture in 1896 and produced high-quality silk. The products were reeled in a factory by young female workers from rural areas who had appropriate skills and experience. After World War I, an expansion in the business caused a shortage of workers at the factory. In response, the management innovated a system for the employment of rural girls.This paper studies the formation of the recruitment system and analyzes how it was implemented by Gunze between 1925 and 1930. The management strategy was to select their employees carefully. First, they refused applications from girls under age in spite of the labor shortage. Only girls aged fifteen and over could get a job and enter the training program. Moreover, they included testing of the candidate's aptitude in the employment examination. Thanks to this, the training period was reduced from six to four months, and the number of trained workers increased.They also considered recruiting highly skilled workers from other factories and areas. This, however, would require reeducation of the workers, and they therefore did not develop this method of employment.In conclusion, the original recruitment system was a precondition for the systematization of the personnel training within industry, which made a contribution to the strict quality control.

シルクを起点とする感性と未来技術 高品質シルクとその無菌周年蚕糸生産技術

シルクを起点とする感性と未来技術 高品質シルクとその無菌周年蚕糸生産技術

Textiles and Industrial Transition in Japan by Dennis L. McNamara

TECHNOLOGY AND CULTURE Book Reviews 267 rarely mentioned, nor are the individuals who pressed for the adop­ tion of these systems throughout the industry. Some of the illustra­ tions and diagrams genuinely help the reader understand specific technologies but, inexplicably, several topics lack needed visual assis­ tance. Fishbein similarly discusses key elements ofdigital technology in a separate chapter, and he concludes with a glimpse at future technologies, such as artificial intelligence. An engineer familiar with instrumentation and control systems will be able to complete these technical pictures, but both he and the aviation historian will find it difficult to discover much about the creative process that led to these technologies or about the effects offlight management tech­ nology on the aerospace industry. Reading this book, I sensed a number of important questions that Fishbein implies, even if he does not actually ask and answer them. Perhaps this is the book’s strongest point. Avionics and navigation systems are a vital, but as yet understudied, part ofair transportation. With Flight Management Systems, Fishbein brings this fascinating field out of the cockpit, and he furnishes historians with several ideas for additional scholarship. J. Lawrence Lee Mr. Lee is a professional engineer and a doctoral student in the history of technol­ ogy at Auburn University. His dissertation examines the development of American wind tunnels. He is also chair of the History and Heritage Committee of the Ameri­ can Society of Mechanical Engineers. Textiles and Industrial Transition inJapan. By Dennis L. McNamara, Ithaca, N.Y.: Cornell University Press, 1995. Pp. xvii+206; tables, notes, index. $37.50 (cloth). Textile making has a long, proud history in Japan. The firms of Nishijin in Kyoto became famous in the 1600s for their high-quality silk. Later a cottage industry in cotton spinning and weaving thrived in the Japanese countryside. It began to disappear in the 1880s as Japan developed a modern textile industry that grew rapidly to chal­ lenge Great Britain and the United States by the 1930s. Under the exigencies of war, Japan’s textile industry was both dismanded and destroyed. It did rise again after the war to spearhead a postwar eco­ nomic revival, but by the 1960s keen competition from low-cost tex­ tile makers abroad posed severe problems forJapan’s textile indus­ try. During the last thirty years the industry has undergone a continuous process of economic adjustment and organizational ad­ aptation. The purpose ofDennis McNamara’s monograph is to characterize the political processes that shaped the transition in theJapanese tex­ tile industry between the 1960s and the 1990s. His book is thus one of many studies contributing to the Japanese industrial policies de­ 268 Book Reviews TECHNOLOGY AND CULTURE bate. The seminal work in this field is ChalmersJohnson’s MITIand the Japanese Miracle (Stanford, Calif.: Stanford University Press, 1982). Johnson argued that Japan’s development as an economic superpower was the product of technocratic guidance by powerful bureaucrats in the Ministry of International Trade and Industry and the Ministry ofFinance. His work has spawned a small army ofoppo­ nents who have consistently taken issue with his interpretation. Other scholars have examinedJapan’s textile industry and the pol­ icies shaping its alteration. Ronald Dore has studied how small and medium-sized firms dealt with recession in the 1970s, and Robert Uriu has examined textiles as one of several case studies in a mono­ graph that deals with the management of industrial decline more generally. McNamara has adopted a method that complements theirs nicely. He employs a holistic sociological approach to the study of textile industry policy after the 1960s and examines in turn each set of actors or institutions that play a role in the industry. These include the industry as a whole, its individual firms, trade asso­ ciations, textile workers, and the state, as well as the general trading houses that import raw materials and export finished goods and the fashion houses in Japan that are key customers of the major textile firms. This broad historical and sociological approach enables McNa­ mara to produce a persuasive argument, well documented with pub­ lished materials and interview data. He finds that neocorporatism has characterized the political process of transition in the textile in...

The Ewo Filature: A Study in the Transfer of Technology to China in the 19th Century

The Ewo Filature: A Study in the Transfer of Technology to China in the 19th Century