The Characterization of Some Ancient Egyptian Funerary Linens from the Twenty-First Dynasty Discovered in the Bab El-Gasus Excavation

The ancient Egyptians had a distinct and flourishing textile industry with diverse characteristics. The developments in archaeological textile studies over the last few decades have assisted in identifying the techniques used in the manufacture of fabrics and demonstrated the complexity of this ancient industry. The ancient Egyptians are well-known for the production of linen fabrics of varying structures and purposes for everyday use by different social classes. The Bab El-Gasus tomb at Deir El-Bahari, the tomb of the priests and priestesses of Amun, is one of the most important excavations for this subject as within the tomb several types of funerary linen textiles from the Twenty-First Dynasty (1070–945 BC) were discovered. This paper aims to characterize some of these linen pieces that were preserved and displayed at the Egyptian Museum in Cairo. The pieces are of high-quality linen, were decorated, and retain their original colours. Investigations were carried out to study their main textile characteristics such as thread diameter, twist direction, thread count and weave type, in addition to characterizing the diagnostic features of the textiles such as fringes, selvedges, self-bands, hues, decoration and their state of deterioration. A Dino-Lite portable digital microscope was used to examine the linen textiles. There were various significant findings and the study revealed some of the distinctive characteristics and versatility of ancient Egyptian textiles, offering new insights for the textile production techniques used at that time.

Investigating the Performance of Sewn Seams from Woven Fabrics

Seam performance ensures the durability, attractiveness, strength etc. of the sewn garments. Fabric types, fabric densities, fabric strength, seam types, sewing thread count, thread strength, stitch densities and stitch types influence the performance of a sewn seam. This paper investigates the performance of sewn seam of various structure of woven fabric. The variables of this research are stitch densities (SPI), sewing thread count, seam types and woven structures. We conduct our research over plain, twill 2/1, twill 2/2, oxford and poplin woven structure. Firstly, we apply lockstitch (301) to produce superimposed, lapped and bound seam on the woven sample by using thread count 27 Tex, 30 Tex, 20/2 Tex, 40 Tex, 40/2 Tex, 40/3 Tex having stitch densities (SPI) 8, 10 and 12. Then according to ASTM D1683 standard, we measured the tensile strength test and recorded the seam breaking strength (N). We apply error bars over each diagram to investigate the standard deviation. Finally, we discuss four hypothesis to conclude our research work. We found higher seam breaking strength with the increase of thread count and SPI. The bound seam samples has shown superior seam breaking strength than superimposed and lapped seam; poplin structure surpassed to others. The seam efficiency of the samples varies from 60–90% and do not exceeds 100%. Finally, we found some significant alternatives hypothesis of the population since F values exceeded F critical values for the sewn seam.

Comprehensive characterization of protective face coverings made from household fabrics

Background Face coverings constitute an important strategy for containing pandemics, such as COVID-19. Infection from airborne respiratory viruses including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can occur in at least three modes; tiny and/or dried aerosols (typically < 1.0 μm) generated through multiple mechanisms including talking, breathing, singing, large droplets (> 0.5 μm) generated during coughing and sneezing, and macro drops transmitted via fomites. While there is a growing number of studies looking at the performance of household materials against some of these situations, to date, there has not been any systematic characterization of household materials against all three modes. Methods A three-step methodology was developed and used to characterize the performance of 21 different household materials with various material compositions (e.g. cotton, polyester, polypropylene, cellulose and blends) using submicron sodium chloride aerosols, water droplets, and mucous mimicking macro droplets over an aerosol-droplet size range of ~ 20 nm to 0.6 cm. Results Except for one thousand-thread-count cotton, most single-layered materials had filtration efficiencies < 20% for sub-micron solid aerosols. However, several of these materials stopped > 80% of larger droplets, even at sneeze-velocities of up to 1700 cm/s. Three or four layers of the same material, or combination materials, would be required to stop macro droplets from permeating out or into the face covering. Such materials can also be boiled for reuse. Conclusion Four layers of loosely knit or woven fabrics independent of the composition (e.g. cotton, polyester, nylon or blends) are likely to be effective source controls. One layer of tightly woven fabrics combined with multiple layers of loosely knit or woven fabrics in addition to being source controls can have sub-micron filtration efficiencies > 40% and may offer some protection to the wearer. However, the pressure drop across such fabrics can be high (> 100 Pa).

An integrated approach to develop performance index of bed linen fabric

The quality of woven bed sheets is often conveyed by the thread count i.e. the number of threads per square inch of the fabric. However, bed linens need to encompass three essential characteristics such as high breathability, moisture absorbency and soft feel to ensure quality sleep. Sleep quality is significantly influenced by thermal regulation characteristics such as thermal conductivity, air permeability and moisture vapor permeability of the sheeting cloth. Hand of sheeting material is also considered as one of the most important attributes of a high quality bed linen as it comes in direct contact with human body for a substantial duration. In this research, an effort has been made to develop an objective method to measure the performance behavior of the bed linen fabric. Performance index is a calculation of how well a material works to meet its defined goals. The subjective assessment of bed linen performance indicators was conducted by expert opinion to decide the properties affecting the bed linen performance index (BLPI) along with their weightage. Discriminant analysis and coefficient of concordance was determined to find the agreement among the judges. The eight shortlisted properties were determined objectively and the results were normalized to shrink the data in the scale 1 to 5. The weightage and normalized data was used to determine the BLPI by using the developed equation. A high correlation of 0.84 was found between the subjective and objective BLPI. This study concludes that the BLPI could be estimated well using the developed equation.

A Brief Review of Materials and Designs for Homemade Masks to Protect Against COVID-19

It is highly likely that the wearing of face masks reduces the rate of respiratory infections (e.g. SARS-CoV-2), to protect both the user and those around them. This paper sets out to review the areas that effect the efficacy of masks, the materials, design, hygiene and fit testing, in order to make recommendations as to how to make mask from resources found in most homes for when commercial models are unavailable. This paper finds that a mask constructed with a filter made from high thread count cotton is likely to provide a reasonable level of protection (~70% filtration) and that if a layers of other materials such as chiffon or silk is added the filtration may be much higher (~90%). There is also some promise in less available materials such as vacuum cleaner bags and air conditioner filters. Examples of fabric and rigid designs are reviewed but most are limited by the fit to the users which is hard to determine in a home setting. It would be extremely helpful if a method was devised for people to test or be tested for the fit of home made masks. In the mean time careful thought should be given to whether the user judges a good fit. Users should also be careful to practice other means of hygiene and distancing.

Energy-Efficient Thread Mapping for Heterogeneous Many-Core Systems via Dynamically Adjusting the Thread Count

Improving computing performance and reducing energy consumption are a major concern in heterogeneous many-core systems. The thread count directly influences the computing performance and energy consumption for a multithread application running on a heterogeneous many-core system. For this work, we studied the interrelation between the thread count and the performance of applications to improve total energy efficiency. A prediction model of the optimum thread count, hereafter the thread count prediction model (TCPM), was designed by using regression analysis based on the program running behaviors and heterogeneous many-core architecture feature. Subsequently, a dynamic predictive thread mapping (DPTM) framework was proposed. DPTM uses the prediction model to estimate the optimum thread count and dynamically adjusts the number of active hardware threads according to the phase changes of the running program in order to achieve the optimal energy efficiency. Experimental results show that DPTM obtains a nearly 49% improvement in performance and a 59% reduction in energy consumption on average. Moreover, DPTM introduces about 2% additional overhead compared with traditional thread mapping for PARSEC(The Princeton Application Repository for Shared-Memory Computers) benchmark programs running on an Intel MIC (Many integrated core)heterogeneous many-core system.

I/O in the ATLAS multithreaded framework

Scalable multithreading poses challenges to I/O for the ATLAS experiment. The performance of a thread-safe I/O strategy may depend upon many factors, including I/O latencies, whether tasks are CPU- or I/O-intensive, and thread count. In a multithreaded framework, an I/O infrastructure must efficiently supply event data to and collect it from many threads processing multiple events in flight. In particular, on-demand reading from multiple threads may challenge caching strategies that were developed for serial processing and may need to be enhanced. This I/O infrastructure must also address how to read, make available, and propagate in-file metadata and other non-event data needed as context for event processing. We describe the design and scheduling of I/O components in the ATLAS multithreaded control framework, AthenaMT, for both event and non-event I/O. We discuss issues associated with exploiting the multithreading capabilities of our underlying persistence technology, ROOT, in a manner harmonious with the ATLAS framework?s own approach to thread management. Finally, we discuss opportunities for evolution and simplification of I/O components that have successfully supported ATLAS event processing for many years from their serial incarnations to their thread-safe counterparts.