Dialdehyde Starch in Paper Coatings Containing Soy Flour-Isolated Soy Protein Adhesive

A combination of soy flour and isolated soy protein was investigated as the adhesive in pigmented paper coatings that contained dialdehyde starch (DA) as the insolubilizing agent. A coating formula of 50% solids made up of 8.3 parts soy flour, 8 parts isolated soy protein and 0.5 part DAS per 100 parts of clay exhibited pseudoplastic and thixotropic flow properties characteristic of coating colors containing more costly protein adhesives. Both was pick and wet-rub resistance of the paper coating were improved and putrefaction retarded by the use of DAS in the formulation. Brightness, was pick and wet-rub resistance values compared favorably with those of a reference coating containing 12.5 parts of isolated soy protein and 0.5 parts DAS per 100 parts of clay.     

Stackmaker: An Environment for Creating Hypermedia Learning Material

Hypermedia has for some time now been proposed as an adjunct to printed material within the educational process. However, creating a highly interconnected hypermedia network is complex and time consuming, with overviews of the content and structure of the information seemingly essential in order to avoid the disorientation and cognitive overload problems often described.

This paper describes an environment designed to remove much of the burden of creating such support facilities, allowing the teacher to concentrate on the content and structure of the information presented.     

Understanding the Friction Mechanisms Between the Human Finger and Flat Contacting Surfaces in Moist Conditions

Human hands sweat in different circumstances and the presence of sweat can alter the friction between the hand and contacting surface. It is, therefore, important to understand how hand moisture varies between people, during different activities and the effect of this on friction. In this study, a survey of fingertip moisture was done. Friction tests were then carried out to investigate the effect of moisture. Moisture was added to the surface of the finger, the finger was soaked in water, and water was added to the counter-surface; the friction of the contact was then measured. It was found that the friction increased, up until a certain level of moisture and then decreased. The increase in friction has previously been explained by viscous shearing, water absorption and capillary adhesion. The results from the experiments enabled the mechanisms to be investigated analytically. This study found that water absorption is the principle mechanism responsible for the increase in friction, followed by capillary adhesion, although it was not conclusively proved that this contributes significantly. Both these mechanisms increase friction by increasing the area of contact and therefore adhesion. Viscous shearing in the liquid bridges has negligible effect. There are, however, many limitations in the modelling that need further exploration.     

Interferometric measurement of instantaneous local heat transfer from a horizontally vibrating isothermal cylinder

Local instantaneous heat-transfer coefficients were measured for free convection from an isothermal cylinder vibrating sinusoidally in a horizontal plane. The results show that the heat-transfer coefficient is strongly dependent upon the ratio of amplitude of vibration to cylinder diameter, $\text{A}\text{D}$. For values of $\text{A}\text{D}$less than approximately 0·25, a critical vibration intensity was observed below which vibration caused only small increases in the heat-transfer rate; however, at $\text{A}\text{D}$ greater than 0·25, the critical vibrational intensity did not appear to exist because the heat transfer from the cylinder increased as soon as the vibrational speed increased from zero. A correlation of the data is presented which predicts the increase in average heat transfer from the cylinder to air above the free convective rate.The correlation also applies to data for much larger vibrational intensities.     

Spin-filtering effect in GaAsN: electron-nuclear spin dynamics of Ga<Superscript>3+</Superscript> centers

The impact of Ga³⁺ centers in the spin-filtering effect observed in GaAsN samples is investigated through a model based on the master equation approach. Our results, compared with experimental data, show that, Ga³⁺ are essential to understanding the behavior of the photoluminescence intensity and degree of circular polarization as functions of a Faraday configuration magnetic field. The model presented here takes into account the interplay of Ga²⁺ and Ga³⁺ centers, Zeeman and hyperfine interaction. The various processes that drive the spin-filtering effect, as the spin selective capture of conduction band electrons into Ga centers are also considered here.     

CD45 (leukocyte common antigen) immunoreactivity in metastatic undifferentiated and neuroendocrine carcinoma: a potential diagnostic pitfall

Leukocyte common antigen (CD45/LCA) and keratin expression are generally mutually exclusive in diagnostic surgical pathology. CD45 reactivity is a reliable indicator of the hematolymphoid nature of a tumor, whereas keratin reactivity is typical of epithelial differentiation (carcinomas and some sarcomas). Some lymphomas, however, might lack detectable CD45 expression, whereas occasional ones might express keratins. CD45 immunoreactivity has been considered exquisitely specific for hematopoietic cells. We report three undifferentiated or neuroendocrine carcinomas that showed membrane-associated immunoreactivity for CD45 in addition to showing distinctive keratin cocktail (AE1/AE3) and epithelial membrane antigen reactivity (all cases); also, keratin 7 was demonstrated in one case and keratin 19 in another. Two cases were lymph node metastases of undifferentiated carcinomas, one of them from the lungs and the other of an unknown origin; the former case showed neuroendocrine features. The third case represented a pulmonary large-cell undifferentiated carcinoma. These cases were negative for lineage-specific leukocyte antigens and did not show clonal immunoglobulin heavy-chain gene rearrangements. Electron microscopic studies demonstrated desmosomes and keratin-like tonofilaments in all three cases, thus confirming the epithelial nature of these tumors. The exceptional membrane staining for CD45 seen in these undifferentiated carcinomas might be comparable to experimentally detected incorporation of leukocyte antigens into the cell membranes of nonleukocytic cells in a leukocyte-rich environment. This rare diagnostic pitfall should be considered in the diagnostic surgical pathology of undifferentiated tumors. It is best avoided by employing a panel of leukocyte and epithelial antigens and by use of electron microscopy, if possible.     

Regulation of monocyte IL-10 synthesis by endogenous IL-1 and TNF-alpha: role of the p38 and p42/44 mitogen-activated protein kinases

IL-10 is an anti-inflammatory cytokine with potent immunomodulatory effects, including inhibition of cytokine production. However, regulation of monocyte IL-10 production is poorly understood. In this report we have investigated the mechanisms of LPS-induced IL-10 production by human peripheral blood monocytes and demonstrate that IL-10 synthesis is uniquely dependent on the endogenous proinflammatory cytokines IL-1 and/or TNF-alpha. LPS signal transduction in monocytes has been shown to involve activation of the p38 and p42 mitogen-activated protein kinase (MAPK) cascades. The results in this paper indicate that inhibition of p38 MAPK potently inhibited the production of IL-10, IL-1beta, and TNF-alpha, whereas blockade of the p42/44 MAPK pathway, while partially inhibiting TNF-alpha and IL-1beta production, had no effect on monocyte secretion of IL-10. Furthermore, neither the inhibition of monocyte TNF-alpha induced by IL-10 nor the stimulation of soluble TNF receptor production was affected by inhibition of the p42/44 MAPK pathway, suggesting that this signaling event is not involved in either monocyte production of or anti-inflammatory responses to IL-10. These data raise the interesting possibility that proinflammatory TNF-alpha-mediated effects may be selectively blocked without modulating the induction or the response to IL-10, whereas the signaling events associated with the anti-inflammatory events induced by IL-10 remain to be elucidated.