Cryptographic hash standards: where do we go from here?

Successful attacks against the two most commonly used cryptographic hash functions, MD5 and SHA-1, have triggered a kind of feeding frenzy in the cryptographic community. Many researchers are now working on hash function attacks, and we can expect new results in this area for the next several years. This article discusses the SHA-1 attack and the US National Institute of Standards and Technology's (NIST's) plans for SHA-1 and hash functions in general.     

Measuring trunk motions in industry: variability due to task factors, individual differences, and the amount of data collected

The focus of this study was to determine the amount of data needed to ensure sufficient accuracy in estimating mean trunk motions of employees performing industrial manual materials handling tasks. Over 450 tasks were selected, in which the load weight and the vertical start and destination heights of the activity remained constant throughout the task. Data were collected as employees did their work at the job site, using the Lumbar Motion Monitor. Variance components were estimated in a hierarchical design and used to compute standard errors of mean trunk kinematic measures. These analyses found task-to-task variation to be much larger than the variability due to either multiple employees performing the same task or to repetitive movements within a task. Also, it was found that no significant reduction in the standard errors occurred when data were gathered for more than three employees and three repetitions of each task by an employee. This study indicates that the vast majority of variability in mean trunk motions is accounted for by the design of work tasks, and variations due to repeated cycles of a task or to employees are rather minor. It is also important as a basis for future work on modelling low-back disorder risk based on a job's trunk kinematic measures.     

OF ASPHALT FRACTIONS OBTAINED BY SUPERCRITICAL AND SOLVENT EXTRACTION

ABSTRACT

Supercritical extraction with n-pentane was used to separate asphalt into distinct fractions having different physical and compositional properties. A pilot-scale supercritical unit capable of processing thirty kilograms of asphalt per day was designed and fabricated specifically for asphalt fractionation. The operation and design of the unit is similar to the ROSE (Residuum Oil Supercritical Extraction) process of Keer-McGee. This unit was used to separate asphalt into five different fractions ranging from soft greases to asphaltene-like solids. Supplemental room-temperature solvent fractionation of the hardest of these five using binary pentane/cyclohexane mixtures produces, a total of eight fractions. A variety of analyses provide chemical and physical ctauracterization of the fractions. These include: (1) Corbett Fractionation, (2) FT-IR spectroscopy, (3) size exclusion chromatography, (4) nickel and vanadium atomic absorption, and (5) viscosity     

Rap1a Activity Elevated the Impact of Endogenous AGEs in Diabetic Collagen to Stimulate Increased Myofibroblast Transition and Oxidative Stress

Diabetics have an increased risk for heart failure due to cardiac fibroblast functional changes occurring as a result of AGE/RAGE signaling. Advanced glycation end products (AGEs) levels are higher in diabetics and stimulate elevated RAGE (receptor for AGE) signaling. AGE/RAGE signaling can alter the expression of proteins linked to extracellular matrix (ECM) remodeling and oxidative stressors. Our lab has identified a small GTPase, Rap1a, that may overlap the AGE/RAGE signaling pathway. We sought to determine the role Rap1a plays in mediating AGE/RAGE changes and to assess the impact of isolated collagen on further altering these changes. Primary cardiac fibroblasts from non-diabetic and diabetic mice with and without RAGE expression and from mice lacking Rap1a were cultured on tail collagen extracted from non-diabetic or diabetic mice, and in addition, cells were treated with Rap1a activator, EPAC. Protein analyses were performed for changes in RAGE-associated signaling proteins (RAGE, PKC-ζ, ERK1/2) and downstream RAGE signaling outcomes (α-SMA, NF-κB, SOD-2). Increased levels of endogenous AGEs within the diabetic collagen and increased Rap1a activity promoted myofibroblast transition and oxidative stress, suggesting Rap1a activity elevated the impact of AGEs in the diabetic ECM to stimulate myofibroblast transition and oxidative stress.     

Plastic Extrusion Process Optimization by Inversion of Stacked Autoencoder Classification Machines

In the face of climate change and rising energy prices, lowering energy usage of industrial machines is gaining widespread attention. Αpropriate machine settings could lead to reduced production costs and lower environmental impact, while simultaneously maintaining products' quality. However, defining the complex, nonlinear dependencies between these settings and energy usage or quality in manufacturing is often a challenging task. In the presented work, a method for optimized machine settings recommendation is proposed using inverse classification via autoencoders. The algorithm can suggest operation parameters, based on predefined intervals of energy consumption and product properties. The performance is evaluated on data generated by a digital twin of an extrusion process.     

Starch Graft Copolymers for Water Treatment

Graft polymers produced by the reaction of starch with cationic, anionic and nonionic acrylic monomers show considerable potential as flocculating agents for treatment of industrial and municipal wastewaters, for beneficiation of mineral ores and for retention of clay in filled paper. Performance of the polymers depends on the nature of the system being treated and on the structure of the starch grafts. Percent add-on, grafting frequency, molecular weight of grafted chains and ionic charge are important variables in starch graft polymer structure that influence performance. Effectiveness of the polymers as flocculants has been demonstrated in laboratory tests and in on-site trials. Methods of preparation have been developed and the various polymers characterized.     

Polymer Distribution in Grafted Starch Granules by Scanning Electron Microscopy

The location of grafted polymer within the starch granule matrix was determined by scanning electron microscopy for two wheat starch graft copolymers prepared by ⁶⁰Co-initiated graft polymerization of a mixture of acrylamide and N,N,N-trimethylaminoethyl metacrylate methyl sulfate (TMAEMA-MS). For a graft copolymer containing 16% synthetic polymer, prepared by the simultaneous irradiation of a starch-monomer mixture, grafting took place throughout most of the granule interior. However, a graft copolymer containing 31% synthetic polymer, prepared by reaction of preirradiated starch with a water solution of monomers, was grafted largely near the granule surface. In contrast to starch-g-poly(acrylamide-co-TMAEMA-MS) prepared by simultaneous irradiation, irradiation of a starch-styrene mixture gave predominantly surface grafting. All graft copolymers had the outward appearance of starch granules, and this appearance was retained even after removal of the starch moiety by hydrolysis. The size distribution of wheat starch granules, as determined by Coulter counter measurements, was not greatly altered by graft polymerization of acrylamide-TMAEMA-MS; however, graft polymerization of styrene onto corn starch significantly increased granule size.