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The article discusses a study which examined the solvent resistance and mechanical properties of thermoplastic elastomer blends prepared by dynamic vulcanization. In this study, three thermoplastics polyamide (PA), polypropylene (PP), and polybutylene terephthalate (PBT) were analyzed in combination with two rubbers. The blends were also tested for exposure to solvents, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM).

In recognition of your commitment to effective reading instruction through your dedicated research into language development and other cognitive skills in children and adults with learning and attention difficulties. [ABSTRACT FROM AUTHOR]

Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasmamass spectrometry which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax and disodium octaborate tetrahydrate (DOT) in biological matrices. In vitro human skin percent doses of boric acid absorbed were 1.2 for a 0.05% solution, 0.28 for a 0.5% solution, and 0.70 for a 5.0% solution. These absorption amounts translated into flux values of, respectively, 0.25, 0.58, and 14.58 μg/cm 2/h, and permeability constants ( Kp) of 5.0 x 10 -4, 1.2 x 10 -4, and 2.9 x 10 -4 cm/h for the 0.05%, 0.5%, and 5.0% solutions. The above in vitro doses were at infinite, 1000 μL/cm 2 volume. At 2 μL/cm 2 (the in vivo dosing volume), flux decreased some 200-fold to 0.07 μg/cm 2/h and Kp of 1.4 x 10 -6 cm/h, while percent dose absorbed was 1.75%. Borax dosed at 5.0%/1000 μL/cm 2 had 0.41 percent dose absorbed, flux at 8.5 μg/cm 2/h, and Kp was 1.7 x 10 -4 cm/h. Disodium octaborate tetrahydrate (DOT) dosed at 10%/1000 μL/cm 2 was 0.19 percent dose absorbed, flux at 7.9 μg/cm 2/h, and Kp was 0.8 x ICH cm/h. These in vitro results from infinite doses (1000 μL/cm 2) were a 1000-fold greater than those obtained in the companion in vivo study. The results from the finite (2 μL/cm 2) dosing were closer (10-fold difference) to the in vivo results. General application of infinite dose percutaneous absorption values for risk assessment is questioned by these results. [ABSTRACT FROM AUTHOR]

Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry, which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological matrices. This made it possible, in the presence of comparatively large natural dietary boron intakes for the in vivo segment of this study, to quantify the boron passing through skin. Human volunteers were dosed with 10B-enriched boric acid, 5.0%, borax, 5.0%, or disodium octaborate tetrahydrate, 10% in aqueous solutions. Urinalysis, for boron and changes in boron isotope ratios, was used to measure absorption. Boric acid in vivo percutaneous absorption was 0.226 (SD = 0.125) mean percent dose, with flux and permeability constant ( Kp) calculated at 0.009 μg/cm 2/h and 1.9 x 10 -7 cm/h, respectively. Borax absorption was 0.210 (SD = 0.194) mean percent dose, with flux and Kp calculated at 0.009 μg/cm 2/h and 1.8 x 10 -7 cm/h, respectively. DOT absorption was 0.122 (SD = 0.108) mean percent, with flux and Kp calculated at 0.01 μg/cm 2/h and 1.0 x 10 -7 cm/h, respectively. Pretreatment with the potential skin irritant 2% sodium lauryl sulfate had no effect on boron skin absorption. These in vivo results show that percutaneous absorption of boron, as boric acid, borax, and disodium octaborate tetrahydrate, through intact human skin is low and is significantly less than the average daily dietary intake. This very low boron skin absorption makes it apparent that, for the borates tested, the use of gloves to prevent systemic uptake is unnecessary. These findings do not apply to abraded or otherwise damaged skin. [ABSTRACT FROM AUTHOR]

A number of new location models which utilize the notion of coverage were developed, tested and utilized in a study of the Baltimore City Fire Protection System. These models extend the location decision to include not only specification of the sites of the basic facilities but also the distribution of specialized equipment and/or manpower among those sites. They are seen as more realistic representations of the location decisions which are required in public sector applications. [ABSTRACT FROM AUTHOR]

Describes a generic step-by-step method for business process management (BPM) which encompasses methods employed in industry from incremental improvements to reengineering. Survey of major US companies' approaches to process quality management; Continuous improvement; Critical success factors; Activity-based costing; Analytic hierarchy process.

The article offers information on the arts and arts education. It forwards that published results of research in arts and arts education have been a reality for more than one hundred years. It is also observed that art educators are still in an uncomfortable state of mind with respect to research on the arts and arts education. It is also mentioned that art educators have blindly attempted to name research problems on the basis of methodologies which were developed and used in related areas.

Describes the practical problems that the director of human resources of the North American subsidiary of a French group encountered related to cultural misunderstandings and stereotyping. Specifically deals with the difficulties he experienced when organizing internal training programmes, harmonizing a human resources reporting system and developing a set of "best practices" across cultural barriers. [ABSTRACT FROM AUTHOR]

Capacity is generally considered only in one sense – to provide the means for producing a product or service. Defines capacity as serving two functions – to provide the means for producing a long-run, stable level of a good or service, and to provide the means to adapt to fluctuations in demand over the short run and intermediate runs. Given this definition, develops the implications for strategic capacity planning and offers a model for firms to carry out this planning. Presents examples of where this model has been followed and discusses the implications. [ABSTRACT FROM AUTHOR]

Literature from the first half of this century report concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry which now allows quantitation of percutaneous absorption of 10B in 10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological matrices. This made it possible, in the presence of comparatively large natural dietary boron intakes for the in vivo segment of this study, to quantify the boron passing through skin. Human volunteers were dosed with 10B-enriched boric acid, 5.0%, borax, 5.0%, or disodium octaborate tetrahydrate, 10%, in aqueous solutions. Urinalysis, for boron and changes in boron isotope ratios, was used to measure absorption. Boric acid in vivo percutaneous absorption was 0.226 (SD = 0.125) mean percentage dose, with flux and permeability constant (Kp) calculated at 0.009 μg/cm2/h and 1.9 × 10−7 cm/h, respectively. Borax absorption was 0.210 (SD = 0.194) mean percentage of dose, with flux; and Kp calculated at 0.009 μg/cm2/h and 1.8 × 10−7 cm/h, respectively. DOT absorption was 0.122 (SD = 0.108) mean percentage, with flux and Kp calculated at 0.01 μg/cm2/h and 1.0 × 10−7 cm/h, respectively. Pretreatment with the potential skin irritant 2% sodium lauryl sulfate had no effect on boron skin absorption. In vitro human skin percentage of doses of boric acid absorbed were 1.2 for a 0.05% solution, 0.28 for a 0.5% solution, and 0.70 for a 5.0% solution. These absorption amounts translated into flux values of, respectively, 0.25, 0.58, and 14.58 νg/cm2/h and permeability constants (kp) of 5.0 × 10−4, 1.2 × 10−4, and 2.9 × 10−4 cm/h for the 0.05, 0.5, and 5.0% solutions. The above in vitro doses were at infinite, 1000 μl/cm2 volume. At 2 μl/cm2 (the in vivo dosing volume), flux decreased some 200-fold to 0.07 μg/cm2/h and Kp, of 1.4 × 10−6 cm/h, while percentage of dose absorbed was 1.75%. Borax dosed at 5.0%/1000 μl/cm2 had 0.41% dose absorbed, flux at 8.5 μg/cm2/h, and Kp, was 1.7 × cm/h. Disodium octaborate tetrahydrate (DOT) dosed at 10%/1000 μl/cm2 was 0.19% dose absorbed, flux at 7.9 μg/cm2/h, and Kp, was 0.8 × 10−4 cm/h. These in vitro results from infinite doses (1000 μl/cm2) were 1000-fold greater than those obtained in the companion in vivo study. The results from the finite (2 μ/cm2) dosing were closer (10-fold difference) to the in vivo results. General application of infinite dose percutaneous absorption values for risk assessment is questioned by these results. These in vivo results show that percutaneous absorption of boron, as boric acid, borax, and disodium octaborate tetrahydrate, through intact human skin, is low and is significantly less than the average daily dietary intake. This very low boron skin absorption makes it apparent that, for the borates tested, the use of gloves to prevent systemic uptake is unnecessary. These findings do not apply to abraded or otherwise damaged skin. [ABSTRACT FROM PUBLISHER]

This paper solves a financial decision-making model in investment activity. Although highly simplified, it leads to a very complicated nonlinear optimal control problem whose complete feedback control solution is obtained by means of a reverse-time construction technique. A dispersal surface with nonunique solutions is present in the optimal solution because of the nonconcavity of the problem. [ABSTRACT FROM AUTHOR]

The minimum covering sphere problem, with applications in location theory, is that of finding the sphere of smallest radius which encloses a set of points in E[sup n]. For a finite set of points, it is shown that the Wolfe dual is equivalent to a particular quadratic programming problem and that converse duality holds. A finite decomposition algorithm, based on the Simplex method of quadratic programming, is developed for which computer storage requirements are independent of the number of points and computing time is approximately linear in the number of points. [ABSTRACT FROM AUTHOR]

Discusses the key rights and responsibilities of employees and companies in the U.S. Rights of workers; Complementary list of employer rights and responsibilities; Policy implications on management.