Silk Thread Research Articles

Lustrous silk and dark wool: materiality, colour and the refashioning of St. Augustine in the medieval imagination

Abstract Male bodies dressed in brilliant silk clothing conveyed messages of power in late medieval Italy. Previous scholars examined how these glamorous bodies reflected contemporary ideals of gentility and whiteness in a courtly context. This article shifts the attention from secular to religious contexts through examining the fictive materiality of the attire of St. Augustine. Silk and wool were two driving forces of the pre-industrial economy. Yet they are rarely considered together, and the discussion has focussed on production. Much less thought has been put into the social implications. By pulling together the threads of silk and wool, this article illuminates how St. Augustine’s dual silk-woollen attire transformed his body in the medieval imaginary and became a powerful visual tool to communicate messages of leadership, legitimacy and kinship.

Model for estimating red mulberry leaf area using a genetic algorithm

The success of sericulture depends directly on the quality and quantity of mulberry leaves, as it is essential for the feeding and development of silkworm caterpillars and, consequently, influences the quality of the silk thread manufactured. The estimation of mulberry leaf area is important to have plant development and growth indicators, such as transpiration intensity, net assimilation rate, leaf area ratio, specific leaf area and leaf area index, which allow predicting crop productivity. Thus, the objective of this study was to develop and test a model capable of estimating the red mulberry leaf area using a genetic algorithm. The model was adjusted with the proposed stochastic optimization method. The mean error found for the tested dataset was approximately 228.17 mm2 in sample space with mean leaf area of 6515.55 mm2. The information generated allows applying the model to estimate red mulberry leaf area in future studies.

Rapid evasive behaviors of diamondback moth larvae against ants

Abstract Larvae of the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae) wriggle vigorously backward when physically stimulated. To explore whether this behavior is effective against ant attacks on their host plants with three-dimensional structures, we experimentally observed DBM larval movements and consequences thereof when attacked by Formica japonica (Hymenoptera: Formicidae) ants on the upper and lower surfaces of host plant leaves. On the upper surfaces of leaves, DBM larvae wriggled backward in response to ant attacks, and most larvae hung from leaf edges by spinning silk threads. On the lower surfaces of leaves, DBM larvae did not wriggle backward but immediately hung from the lower surface in response to attacks. No ants were able to pursue hanging larvae. We conclude that wriggling backward by DBM larvae belongs to a sequence of evasive movements against ant attacks on upper leaf surfaces. To our knowledge, this is the first report of combined wriggling and hanging behaviors by Lepidopteran larvae that are effective against ants in three-dimensional habitats.

Impact of Muga Silkworm Culture in Augmenting Rural Income of Assam, India

Mugaculture is traditionally practiced by the rural population of Assam. Rearing of Muga silk worm is done by most of the villagers belonging to various districts of Assam as an additional source of income. Envisaging the prospects of Muga industry in Assam, the present work tries to study the role of Mugaculture to alleviate rural poverty. The present study was carried out in Dhemaji district of Assam during 2020 to 2022. The study focuses to examine the different aspects of Muga culture and its significance for the livelihood of local people. The parameters identified for analysis included the nature of Mugaculture practices in the study area, the contribution of Mugaculture to rural households and the economic prospects of Mugaculture. The present study finds that income from Mugaculture practices contributes significantly to the total income of the people. The Mugaculture practice in the study area is found to be an avocation that people engage in between other farming activities and people use traditional methods of Mugaculture. Income is generated through selling of cocoon, pupae and muga silk threads. Moreover, a cost-benefit ratio analysis conducted indicates that Mugaculture is a profitable venture of the people.

Usefulness of Hem-o-lok® clips to ligate the gastroduodenal artery in pancreatoduodenectomy

Background/purposePost-pancreatectomy hemorrhage (PPH) is a fatal complication of pancreatoduodenectomy. When complicated by a pancreatic fistula, pancreatic juice contacting the artery may form a pseudoaneurysm and cause arterial bleeding. We used Hem-o-lok® clips to prevent damage to the outer wall of the gastroduodenal artery (GDA). This study evaluated the usefulness of using Hem-o-lok® clips to ligate the GDA stump to prevent PPH. MethodsOverall, 468 patients who underwent PD at our hospital were included. Before July 2020, we ligated the GDA stump using the knot-tying method, which involves double ligation. After July 2020, the GDA stump was double clipped using a 10-mm Hem-o-lok® clip to the residual side without tension on the GDA. Propensity score matching was used to compare cases of pancreatic fistulas that underwent clipping vs. knot-tying. ResultsPropensity score matching resulted in 37 patients in each group. PPH occurred in 12 (16.4%) and 4 (6.9%) patients in the knot-tying and clipping groups, respectively. PPH from the GDA stump occurred in eight (11.0%) and one (1.7%) patient in the knot tying and clipping groups, respectively (P = 0.044). ConclusionsHem-o-lok® clips are safe to apply on the GDA stump during pancreatoduodenectomy to prevent PPH.

Structural, morphological, optical, and antimicrobial study of Mikania micrantha (leaf) extract treated zinc doped cobalt ferrite nanoparticles and antibacterial clothing applications

To manage pathogenic diseases, different applications of nanotechnology have been harnessed to improve the antimicrobial and self-cleaning attributes of materials. The objective of this study is to examine the anti-microbial activity of silk thread; coated (ultra-sonication method) with Zn doped cobalt ferrite nanoparticles with future prospects of developing interlayer of surgical facemask or producing antibacterial wearing. The nanoparticles were synthesized following the co-precipitation method by using Mikania micrantha leaf extract. The potential antibacterial activity (against E. coli and S. aureus) of the thread as well as the nanoparticles was recorded using the Zone of Inhibition (ZOI) test result. XRD results showed the cubic crystal structure and the lattice parameter change due to Zn doping. SEM findings revealed particle agglomeration, though the particles retained an approximately spherical shape of around 52.498 nm for undoped and 32.13 nm for doped materials. FT-IR analysis confirmed that flavonoids from the leaf extract stabilized the nanoparticles. This research investigated the antibacterial capabilities of threads coated with nanoparticles; using the agar well diffusion method, the study established the robust antibacterial capabilities of the nanoparticles-coated thread. Notably, the CoFe2O4 NPs exhibited strong antimicrobial activity against specific bacterial strains, and Zn doping enhances this characteristic.

Endoscopic insertion of an ileus tube with attached silk threads as endoscope grasping points.

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Silk-ma Mixed Woven Textiles in East Asian History

Mixed woven textile (交織物) is a textile woven with yarns of two or more different fibres, in which each yarn contains only one type of fibre. Silk and ma (麻, a Chinese character used to name mainly bast and leaf fibres) are two kinds of the earliest fibre materials used in East Asia. They were opposite in properties, usage and social status in ancient East Asian society where cultures shared the same origin and social hierarchy was extremely rigid under the influence of Confucianism. However, they were woven into silk-ma mixed woven textiles as early as 2355±45 BP in China, as attested by the discovery of archaeological fabric fragments woven with silk and ramie-hemp threads. Archaeological artefacts and ancient documents of silk-ma mixed woven textiles are seldom discovered or recognized, most probably not because of their rare existence in history but because of the lack of precise identification. This paper will share historical evidence of silk-ma mixed woven textiles in the Chinese mainland, the Korean peninsula and the Japanese archipelago, summarize their features and reveal the possible reasons for their elusive presence.

How Do Butterflies Use Silk to Attach their Pupae to Trees?

Butterflies constitute approximately 10% of lepidopteran insects, and along with silkworms, they can produce silk; however, this feature is often ignored. In the present study, we observed two primary methods used by butterflies to hang pupae on trees using silk: pupa adheraena (Danaus chrysippus) and pupa contigua (Papilio polytes). Anchoring the abdominal ends of pupae with a silk pad was the most common method used in both cases, whereas wrapping silk around the body using a silk girdle was a method unique to pupa contigua. The connection between the cremaster and silk pad was observed to be similar to that between the hook and loop of a Velcro fastener, except that the cremaster hook is anchor-shaped rather than being a single hook. Such a connection will remain secure, ensuring the safety of the pupae during exposure to wind and rain. Through determining the mechanical properties of silk, the performance of butterfly silk was found to be weaker than that of silkworm silk. Therefore, the P. polytes silk girdle adopts the strategy of merging a dozen silk threads to improve its strength and toughness, thereby making it difficult to break. In addition, we explained how the protein sequence and structure of butterfly silk impact its performance. In conclusion, we discovered that butterfly pupae develop unique body features to establish secure bonds with silk. This enables them to effectively undergo metamorphosis and endure harsh weather conditions and surroundings.

Impact of Climate Change on Sericulture

Climate change is likely to pose problems to agriculture and its related industries in the future, which could result in both global and local development. The sericulture sector is impacted by climate change in a number of ways. Rising annual mean temperature, irregular rainfall, humidity, lack of management practices, accumulation of anthropogenic greenhouse gases in the atmosphere and lack of management practices will lead to reduced production of raw silk, mulberry leaf yield, silk content, breakage in silk thread during reeling or spinning, water stress, drought, risk of soil acidification and salinization, decomposition of organic matter, Nitrogen fixation, and mineralization of N, P, and S and unpredictable monsoon. The impact of global warming on silkworms is more concerned as they participate in several biotic interactions that are critical to the ecological functioning of our country and significantly boost its GDP.

Studies on the potential risk of amyloidosis from exposure to cultured fibril from silk fibroin

Amyloid A (AA) amyloidosis is induced by administering amyloid fibrils to animals under inflammatory conditions. Silk fibroin (SF), the main component of silk threads, forms amyloid-like fibrils and has been previously reported to induce AA amyloidosis in mice. In this study, SF was cultured in ethanol solution, and after confirming fibril formation through thioflavin T assay, Congo red assay, and observation under electron microscopy, cultured SF ethanol solutions were administered to mice via various routes to investigate the induction of target organs and amyloidosis. As a result, cultured SF ethanol solutions were confirmed to reach the lungs and spleen, but no amyloid deposition was observed. While SF forms amyloid-like fibril structures through cultivation in ethanol solution, its amyloid-enhancing factor (AEF) activity is considered low in mice.

A Study on Cruelty Faced by Silkworms in the Production of Silk

Silk is the fiber that silkworms weave to make their cocoons which are the outer casings that protect them during the pupal stage. But most of the insects used by the silk industry don’t live past this stage, because they are boiled or gassed alive inside their cocoons, which causes the cocoons to begin unraveling so that workers can obtain the silk threads. Some 6,600 silkworms are killed to make just 1 kilogram of silk. The CSB (Amendment) Act, Rules and Regulations have been notified by the Govt. of India to bring quality standards in silkworm seed production. The objective of the research is to create awareness on the cruelty faced by silkworms in the production of silk. The research method used is empirical research and simple random sampling method is used and the sample size is 200 responses and the sample frame is in and around Valluvar kottam. The independent variables are age, gender, education qualifications, occupation and locality. The alternative to this cruel practice is to use another method of obtaining silk called ahimsa silk or wild silk, it is a method of nonviolent silk breeding and harvesting. Wild silk moths are bred, rather than the domestic variety. Roughly 3,000 silkworms are killed to make a single pound of silk. That means that billions, if not trillions, of them are killed for this every year. In order to avoid this practice of killing silkworms we should use an alternative type of fabric or use wild silk

Resection of pleural solitary fibrous tumors with distinct feeding vessels arising from the descending aorta: a case report

BackgroundPleural solitary fibrous tumors (pSFTs) are rare mesenchymal pleural tumors with rich vascularity. Surgical resection is the cornerstone of pSFTs treatment, requiring careful preoperative imaging to delineate lesion extent and vascular supply including contrast-enhanced computed tomography and other examinations depending on its size and characteristics.Case presentationThe patient was a 34-year-old female with a mass measuring approximately 67 × 42 × 65 mm in the left posterior mediastinum. Intraoperatively, the mass demonstrated rich vascularity. Two veins originating from the abdominal cavity entered the lower pole, one converged from the superior pole, draining into the brachiocephalic vein. Additionally, two arteries arose directly from the descending aorta, while several veins drained into the intercostal veins. In response to unexpected intraoperative vascular findings, vascular clips and silk threads were used to ligate them. Subsequently, the tumor was successfully dissected, with approximately 600 ml of blood loss recorded during the 4-hour surgery. The patient exhibited a satisfactory postoperative recovery, and follow-up spanning over six months revealed no indications of recurrence or metastasis.ConclusionsWe firstly present a case of successful resection of a pSFT in a 34-year-old woman with a distinct feeding vessel arising from the descending aorta and describe the related surgical procedures. This case highlights preoperative evaluation of mass vascularity based on contrast-enhanced computed tomography. When blood supply is challenging to clarify, angiography can offer additional details, especially for giant pSFTs. Despite this, thorough intraoperative exploration remains essential to detect unexpected vessels. Appropriate interventions should be customized based on the vascular origins and the surrounding anatomical structures.

Toll-like receptor 4 deficiency affects the balance of osteoclastogenesis and osteoblastogenesis in periodontitis

Toll-like receptor 4 (TLR4) acts as a double-edged sword in the occurrence and development of periodontitis. While the activation of TLR4 in macrophages aids in clearing local pathogens, it can also disrupt innate immune responses, upsetting microecological balance and accelerating the destruction of periodontal bone tissues. To date, the effects of TLR4 on osteogenesis and osteoclastogenesis in periodontitis have not been comprehensively studied.In this study, we investigated the development of periodontitis in the Tlr4−/− mice by ligating their second molars with silk threads. Compared to wild-type (WT) mice, Tlr4−/− mice demonstrated increased resistance to periodontitis-associated bone destruction, as evidenced by decreased bone resorption and enhanced bone regeneration. Mechanistically, the deletion of Tlr4 not only inhibited osteoclast formation by reducing the expression of NFATc1, CTSK and TRAP, but also enhanced osteogenic abilities through increased expression of OCN, OPN and RUNX2. In conclusion, TLR4 tips the balance of osteoclastogenesis and osteogenesis, thereby promoting periodontal bone destruction in periodontitis.

Natural Dyes in Embroideries of Byzantine Tradition, the Collection of Embroidered Aëres and Epitaphioi in the National Museum of Art of Romania

The medieval textiles collection of the National Museum of Art of Romania (MNAR) has been in place since 1865 and nowadays preserves about 1000 medieval and pre-modern weavings and embroideries. These extremely valuable objects, dated between the 14th and the 19th centuries, are mainly religious embroidered garments and veils with special significance in the Byzantine li-turgy. Ecclesiastical embroideries of Byzantine tradition are characterized by a complex technique: metallic threads with a silk core, metallic wires and coloured silk threads are couched over padding on layers of silk and cellulosic supports so as to create relief through light reflection. The silk sup-ports and the sewing threads are coloured, mainly in red, blue, green and yellow hues, and analytical investigations of the dyes used in embroideries preserved in the MNAR, in the Putna and Sucevița Monasteries, have been released in previous studies by the corresponding author. The present work continues the approach with research into dyes in about 25 aëres and epitaphioi from the MNAR collection. Considering their privileged function in the liturgical ritual, these luxurious pieces embroidered with silver, gilded silver or coloured silk threads and decorated with pearls, sequins or semi-precious stones are the most faithful description of the stylistic and technological evolution of the art of post-Byzantine embroidery in the Romanian provinces. The data resulting from the present research will improve the knowledge regarding this topic. Dye analysis was performed by liquid chromatography with diode array detection, while fibres were characterized by infrared spectroscopy (with attenuated total reflectance) and optical microscopy. The biological sources identified—carminic acid-based dyes, redwood, dyer’s broom, weld, indigo-based dyes––will be discussed in correspondence with their use in the embroidery technique: support, lining and embroidery threads, together with other sources previously reported on Byzantine embroideries in Romanian collections, and in similar objects preserved at Holy Mount Athos.

Making shelter for enemies: parasitoid-induced shelter-building behaviour in Paraponyx stagnalis

ABSTRACT Manipulative parasitoids manipulate the behaviour of their hosts in such a way as to benefit their own offspring. Paraponyx stagnalis Zeller is a leaf case worm caterpillar pest of rice and pupates in cases made out of cut leaf blades. These shelters are typically open-ended tubular cases. Its solitary primary endoparasitoid – Apanteles sp. – triggers changes in the way it sews the cases. The observed changes in the folded leaf shelter may serve various functions for the developing parasitoid, such as minimising the risk of hyperparasitism and predation, and enhancing structural stability. To obtain evidence to support these hypotheses, we (1) documented the morphotype of the cases/puparia constructed by unparasitised and parasitised P. stagnalis larval instars, (2) studied the overall rate of primary parasitism of P. stagnalis by Apanteles sp. and (3) studied the rate of hyperparasitism of primary parasitoids in 10 rice fields of south India. Unlike the unparasitised third-instar host larvae, the parasitised larvae sealed the open ends of the folded leaf shelter with silken threads, affixed the puparium to rice leaves and made small cases. The overall parasitism rate was about 40%. However, the hyperparasitism was between 0.6 and 1%. Though the primary parasitism by Apanteles sp. is considerably higher in all 10 fields, the meagre incidence of hyperparasitism strengthens our hypothesis that the modified puparium construction might be triggered by the primary parasitoid and beneficial for the offspring of the primary parasitoid. Our field observations suggest that future experimental studies can bring mechanical evidence for host manipulation by Apanteles sp.

Temporal and spatial expression analysis of periostin in mice periodontitis model.

This study aimed to investigate the temporal and spatial changes in the expression of periostin during periodontal inflammation in mice. A periodontitis model was constructed using silk thread ligation. Mice were randomly divided into five groups including control group, 4-day ligation group, 7-day ligation group, 14-day ligation group, and self-healing group (thread removal for 14 days after 14-day ligation). Micro-CT and histological staining were performed to characterize the dynamic changes in the mouse periodontal tissue in each group. RNAscope and immunohistochemical staining were used to analyze the pattern of changes in periostin at various stages of periodontitis. The cell experiment was divided into three groups: control group, lipopolysaccharide (LPS) stimulation group (treated with LPS for 12 h), and LPS stimulation removal group (treated with LPS for 3 h followed by incubation with medium for 9 h). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of periostin, transforming growth factor-β1 (TGF-β1), and matrix metalloproteinase 2 (MMP2). Significant alveolar bone resorption was observed 7 days after ligation. With increasing duration of ligation, the damage to the mouse periodontal tissue was aggravated, which manifested as increased osteoclasts, widening of the periodontal membrane space, and decreased alveolar bone height. Some degree of periodontal tissue repair was observed in the self-healing group. Periostin expression decreased at 4 and 7 days compared with the control group and increased at 14 days compared with 4 and 7 days. A significant recovery was found in the self-healing group. The qRT-PCR results showed that the expression of periostin and TGF-β1 in the LPS stimulation group decreased compared with that in the control group but significantly recovered in the LPS removal group. Periostin expression in the PDL of mice showed a downward and upward trend with inflammation progression. The significant recovery of periostin expression after removing inflammatory stimuli may be related to TGF-β1, which is crucial to maintain the integrity of the PDL.

Georgian Literary Needlework Pictures, Realization, and Iconic Meaning‐Making

AbstractThis article examines a group of Georgian needlework pictures based on late eighteenth‐century cabinet prints of literary works. Focusing on how these needlework productions were realized, including which decisions regarding the colour of silk thread and chromatic patterns, as well as visual revision, were made by the female silkworker, the article seeks to introduce these pictures as meaningful remediations of printed visual literary culture. The silkworks will be shown to advance interpretations of and to provide framing for six literary characters and the ways in which their stories were iconically rendered by the silkworkers.

The influence of the main elemental constituents of thousand year old barai mud extension of shades of natural dyed silk from marigold flowers

This research aimed (1) to study the main element of thousand year old mud and types of color-giving substances from marigold flowers and (2) to study the causes of silk color change from dark yellow to dark green at Bankhokmuang, Chorakhemark Sub-district, Prakhonchai District, Buriram Province. Firstly, the researcher studied the element of the mud from Barai Prasat Muang Tam and Barai Kuti Ruesi, using EDXRF. Secondly, the researcher studied types of phytochemicals in marigold extract using HCl solution and NaOH solution. Finally, the researcher dyed the silk with marigold flower extract mixed with alum and dyed it with iron ion solution and the mud solution from both sources. The results showed that both muds had the highest amount of Fe2O3, 64.03% of Barai Prasat Muang Tam mud and 44.22% of Barai Kuti Ruesi mud. The coloring substance of marigold extract was flavonoids and had good water solubility. Then the researcher dyed the silk with marigold flower extract mixed with alum because alum contained Al3+ions. The silk was dark yellow. The silk was divided into three groups to be dyed again. The first group was dyed with 1,000 ppm iron ion solution. The second group was dyed with a solution of Barai Prasat Muang Tam mud. The third group was dyed with a solution of Barai Kuti Ruesi mud. All group color changed from dark yellow to dark green. Thus, iron ion solution and both of Barai mud solution were rich in iron ion. This complex compound could form with flavonoids which made golden yellow color turns dark green and sticks to silk threads. It was also water insolubility. The color was not faded. All groups had different shade values at the significance level of 0.05. GRAPHICAL ABSTRACT HIGHLIGHTS Study the main element of thousand year old mud Study area at at Bankhokmuang, Chorakhemark Sub-district, Prakhonchai District, Buriram Province. Causes the color of the silk thread to change from yellow to dark green

HA2-FimA DNA Vaccine Treats Experimental Periodontitis.

To study the therapeutic effect of hemagglutinin-2 and fimbrial (HA2-FimA) vaccine on experimental periodontitis in rats. The first batch of rats was divided into two groups and immunised with pure water or pVAX1-HA2-FimA at the age of 6, 7, and 9 weeks. After sacrificing the animals, total RNA was extracted from the spleens for RNA high-throughput sequencing (RNA-Seq) analysis. The second batch of rats was divided into four groups (A, B, C, D), and an experimental periodontitis rat model was established by suturing silk thread around the maxillary second molars of rats in groups B, C, and D for 4 weeks. The rats were immunised with pure water, pVAX1-HA2-FimA vaccine, empty pVAX1 vector, and pure water at 10, 11, and 13 weeks of age, respectively. Secretory immunoglobulin A (SIgA) antibodies and cathelicidin antimicrobial peptide (CAMP) levels in saliva were measured by enzyme-linked immunosorbent assay (ELISA). All rats were euthanised at 17 weeks of age, and alveolar bone loss was examined using micro-computed tomography (Micro-CT). Through sequencing analysis, six key genes, including Camp, were identified. Compared with the other three groups, the rats in the periodontitis+pVAX1-HA2-FimA vaccine group showed higher levels of SIgA and CAMP (p < 0.05). Micro-CT results showed significantly less alveolar bone loss in the periodontitis+pVAX1-HA2-FimA vaccine group compared to the periodontitis+pVAX1 group and periodontitis+pure water group (p < 0.05). HA2-FimA DNA vaccine can increase the levels of SIgA and CAMP in the saliva of experimental periodontitis model rats and reduce alveolar bone loss.