Quantifying information transfer through a head-attached vibrotactile display: principles for design and control

Vibrotactile displays can extend the perception capabilities of visually impaired persons. Placing such devices on the head promises easy attachment and detachment without reducing other interaction abilities. However, the effectiveness of head-attached vibrotactile displays has never been thoroughly tested. This paper presents the results obtained from experiments with 22?subjects equipped with a display containing 12 coin-type motors equally spaced in a horizontal plane around the upper head region. Our display allowed single- as well as multimotor activation with up to six simultaneously active motors. We identified the minimum and comfort strength of vibrotactile stimulation, and measured the precision in perceiving the accurate number of active motors as well as the precision in localizing the stimuli on the head. While subjects identified the correct number of active motors in 94% of the cases when presented with only one active motor, this precision dropped to 40% for two and down to 5% for five simultaneously active motors. This strongly suggests to avoid multipoint stimulation even though the precision of localizing a position of a stimulus on the head is barely affected by the number of simultaneously active motors. Localization precision, however, varied significantly with the region of the head suggesting that the most front and back regions of the head should be avoided if high precision is required.     

Can mold contamination of homes be regulated? Lessons learned from radon and lead policies

Increasingly, airborne mold in home environments has been linked with asthma exacerbation and other respiratory diseases in both children and adults. This problem is particularly relevanttoday, as Hurricane Katrina has resulted in water damage and mold proliferation in numerous homes on the U.S. Gulf Coast. Policies to control indoor moisture and mold can help solve problems of mold contamination and associated adverse health effects, yet very little attention has been given to developing such policies. We address the question of howto develop effective policies by deriving lessons from successful control of other home environmental contaminants; namely, radon and lead. These two agents are being controlled by a variety of policy approaches, including federal regulations and guidelines, public education, and economic incentives among home buyers and sellers. We analyze the mold problem and identify both similarities and differences with the radon and lead situations in the United States. We recommend policy approaches for controlling mold in homes that rely on home marketing incentives, building and housing codes, and maintenance and rehabilitation regulations, as well as public education initiatives.     

Novel precipitated silicas: an active filler of synthetic rubber

Highly dispersed silicas have been obtained at a semi-technical scale by precipitation from sodium metasilicate solutions using appropriately diluted solutions of ammonium hydrogencarbonate or ammonium chloride. The difference, as compared to the generally applied technology of silica precipitation using acids or their anhydrides, has been the involvement of the precipitation reaction in alkaline media. Attempts have been made at changing the silica surface character from hydrophilic to more hydrophobic, using a modifier from the group of silane coupling agents. The alkoxysilanes modifiers contained groups with chemical affinity towards functional groups of butadiene–styrene rubber. Modification of silica surface using silane coupling agents has been found to improve the reinforcement of vulcanizates, by increasing the tensile and tear strength in particular.     

Concentrated Water Solution of Salts as Solvents for Reactions of Carbohydrates. Part 1: Reactions of Glucose Promoted by Concentrated Solutions of Alkaline and Alkaline Earth Metal Salts

Saturated water solutions of selected alkaline and alkaline earth metal salts have been studied whether or not they catalyze the formation of levulinic acid from glucose. The most active was a solution of magnesium chloride. Activity was further increased in the system (MgCl₂+H⁺). We observed complete inhibition of this reaction by NO₃⁻. Contrary to the generally accepted opinion that formation of hydroxymethylfurfural is only H⁺ catalyzed, we observed activity of the system formed from MgO and MgCl₂ when one starts from glucose. (MgCl₂+ MgO) in water is alkaline.     

Allowable Rates of Fluid Temperature Variations and Thermal Stress Monitoring in Pressure Elements of Supercritical Boilers

ABSTRACT

Allowable rates of fluid temperature changes in critical elements of supercritical steam boilers were determined assuming a quasi-steady state of temperature distribution in pressure components. A method was proposed for monitoring the thermal stresses in the critical pressure components.     

Non‐Glovebox Ethenolysis of Ethyl Oleate and FAME at Larger Scale Utilizing a Cyclic (Alkyl)(Amino)Carbene Ruthenium Catalyst

A ruthenium metathesis catalyst Ru1 bearing a cyclic (alkyl)(amino)carbene (CAAC) ligand is used in the ethenolysis reaction of biosourced 90% pure undistilled ethyl oleate or technical fatty acid methyl esters mixture with grade 3 ethylene, to yield 1‐decene and valuable terminal unsaturated 9‐decenoic acid ester. Under optimized conditions (25 ppm of catalyst Ru1 , 20 bar, 50 °C, 2 h, use of metal scavenger/quenching agent, SnatchCat), the title reaction proceeds with high productivity (up to 70% conversion) and selectivity, and is tested in scale up to 1 L, with the exclusion of a glovebox or Schlenk techniques usage, and the ethenolysis products are isolated by fractional distillation. In addition, a large‐scale synthesis of Ru1 is presented. Practical Applications: Decreasing availability of fossil organic feedstock and current policies of the European Union drives scientists to look for alternative sustainable sources of fine chemicals. In this context, olefin metathesis based ethenolysis of transesterified seed oils studied herein shows a significant potential as a sustainable way to obtain valuable products, such as 1‐decene and valuable terminal unsaturated 9‐decenoic acid ester. Unlike other published studies on ethenolysis, in the present work, the focus is on optimizing this reaction under industrially practical conditions, thus utilizing an air‐stable catalyst, technical grade oleic substrates, grade 3 ethylene, and excluding the use of a glovebox or Schlenk techniques.     

Virus-Like Particles Produced Using the Brome Mosaic Virus Recombinant Capsid Protein Expressed in a Bacterial System

Virus-like particles (VLPs), due to their nanoscale dimensions, presence of interior cavities, self-organization abilities and responsiveness to environmental changes, are of interest in the field of nanotechnology. Nevertheless, comprehensive knowledge of VLP self-assembly principles is incomplete. VLP formation is governed by two types of interactions: protein–cargo and protein–protein. These interactions can be modulated by the physicochemical properties of the surroundings. Here, we used brome mosaic virus (BMV) capsid protein produced in an E. coli expression system to study the impact of ionic strength, pH and encapsulated cargo on the assembly of VLPs and their features. We showed that empty VLP assembly strongly depends on pH whereas ionic strength of the buffer plays secondary but significant role. Comparison of VLPs containing tRNA and polystyrene sulfonic acid (PSS) revealed that the structured tRNA profoundly increases VLPs stability. We also designed and produced mutated BMV capsid proteins that formed VLPs showing altered diameters and stability compared to VLPs composed of unmodified proteins. We also observed that VLPs containing unstructured polyelectrolyte (PSS) adopt compact but not necessarily more stable structures. Thus, our methodology of VLP production allows for obtaining different VLP variants and their adjustment to the incorporated cargo.     

Visualization of particles arrangement during filling stage of polyamide 6 – metal insert injection molding

An isotactic polypropylene filled with talc and mica particles was used for visualization of molten polymer flow lines during filling of mold cavity with metal insert. The talc particles orientation in polypropylene matrix was followed by scanning electron microscopy. For the quantification of platelet particles orientation in molten polymer flow localized near metal wall, the Herman's function was applied. An existence of regions with well oriented, randomly organized talc particles depending on the shape and cross‐section of the channels, was found and reported. The domain with the most disorganized platelet particles was detected in the region where polymer streamed around the sharp corner of the metal insert. Such a kind of disarranged region could be the weakest part of the whole injection molded polymeric element. POLYM. ENG. SCI., 59:E271–E278, 2019. © 2019 Society of Plastics Engineers     

Executive coaching: The need for standards of competence.

Psychologists working in the emerging competency area of "executive coaching" must promote a more complete understanding of what constitutes effectiveness in this arena—particularly when the expected outcome is sustained behavior change. Experienced psychologists must accept accountability for the need to inform and educate corporate decision makers about the core skills, competencies, experience, and related professional issues critical for successful outcomes. These educative efforts are essential if executive coaching for sustained behavior change is to be established as a respected consultative area adding value to organizationally based leadership development initiatives. The purpose of this article is to begin the dialogue among psychologists about the need to become more proactive in their educative efforts with these decision makers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)