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High-speed jet responses in the polar solar wind are enigmatic. Here we measure a jet response that emanates from the southern polar coronal hole on 17 June 2011 at the extreme speed of over 1200?km/s. This response was recorded from the Sun-Earth line in Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) and Large Angle and Spectrometric Coronagraph/C2 and both Solar TErrestrial RElations Observatory Extreme Ultraviolet Imager and COR2 coronagraphs when the three spacecraft were situated ~90° from one another. These certify the coronal 3-D location of the response that is associated with an existing solar plume structure and show its high speed to distances of over 14?RS. This jetting is associated with magnetic flux changes in the polar region as measured by the SDO/Helioseismic and Magnetic Imager instrumentation over a period of several hours. The fastest coronal response observed can be tracked to a time near the period of greatest flux changes and to the onset of the brightest flaring in AIA. This high-speed response can be tracked directly as a small patch of outward moving brightness in coronal images as in Yu et al. (2014) where three slower events were followed from the perspective of Earth. This accumulated jet response has the largest mass and energy we have yet seen in 3-D reconstructions from Solar Mass Ejection Imager observations, and its outward motion is certified for the first time using interplanetary scintillation observations. This jet response is surrounded by similar high-speed patches, but these are smoothed out in Ulysses polar measurements, we speculate about how these dynamic activities relate to solar wind acceleration. An extreme speed jetting feature is observed from three spacecraft perspective viewsThe jetting response is shown for the first time in both IPS and SMEI 3-D reconstructionsThe 3-D relationship between surface brightness and the jet response, as well as the associated field changes, is documented

The present paper provides an analysis of selfboring pressuremeter tests in sand in terms of the state parameter. The method developed herein can be used to determine the insitu sand state from the results of the selfboring pressuremeter test. Unlike the conventional drained pressuremeter analyses that almost exclusively use an elasticperfectly plastic model, the new analysis is based on a strainhardening (or softening) plasticity model in which the angles of friction and dilation are assumed to be a function of the state parameter. The numerical results presented suggest that there is a unique linear correlation between the loading slope of pressuremeter curves and the initial state parameter of the soil. It is therefore possible to deduce the state parameter of the sand from the measured pressuremeter loading slope. The relevance of this new analysis has been confirmed by the results of the pressuremeter test carried out in large calibration chambers.

This paper presents a rigorous lowerbound solution for the bearing capacity of soft clays under embankments. The analysis is carried out by using a numerical technique that is based on the lowerbound theorem and finite elements. It is found that the lowerbound solution obtained in this paper agrees well with the upperbound solutions obtained from Hill and/or Prandtl failure mechanisms. The lowerbound solution for the vertical stresses that a soft foundation can support in combination with a surface shear stress (or shear force) can be used to obtain a safe design for the critical heights of both unreinforced and reinforced embankments by following an iterative procedure similar to that described by Michalowski in 1992. The usual assumption of a uniform shear stress mobilization underneath the embankment is shown to be conservative as it leads to a slightly lower value of the vertical bearing capacity.

Although arsenic and ultraviolet light B (UVB) are both causes for skin cancers, lesions of arsenic-induced Bowen's disease are often confined to sun-protected skin. UVB may play a modulatory role in skin carcinogenesis by arsenic. The purpose of this study was to evaluate the effects and interactions of arsenic and UVB on cell cycle progression and apoptosis. Cultured human keratinocytes were treated with sodium arsenite (1 μM) and/or UVB (50 mJ/cm²) irradiation in different combinations:  (i) arsenic alone, (ii) UVB alone, (iii) arsenic followed by UVB (As−UVB), and (iv) UVB followed by arsenic (UVB−As) treatments. Cell cycle analysis and BrdU pulsing revealed S phase arrest in all treatment groups and growth arrest in As−UVB and UVB−As groups. The terminal deoxynucleotidyl transferase-mediated deoxyuridine nick-end labeling assay showed a higher apoptosis rate in the UVB−As group as compared to that of the As−UVB and UVB groups. UVB irradiation significantly decreased Bcl-2 expression. In either the As−UVB or the UVB−As group, the expression of Bcl-2 was further suppressed as compared to the UVB group. The caspase-3, -8, and -9 relative activities were all increased in the UVB group; however, arsenic significantly enhanced caspase-8 and -3 relative activities in UVB-irradiated keratinocytes (the UVB−As group). Pretreatment with the caspase inhibitor(s) rescued the keratinocytes viability to different degrees with the least in the UVB−As group. Our findings revealed that arsenic enhances UVB-induced keratinocyte apoptosis via suppression of Bcl-2 expression and stimulation of caspase-8 activity. Combined UVB and arsenic treatment resulted in the antiproliferative and proapoptotic effects in keratinocytes. Our results provide the explanation for the rare occurrences of arsenical cancers in the sun-exposed skin and the potential therapeutic role of UVB in arsenic-induced Bowen's disease.

Arsenic (As) is widely distributed in nature, and its contamination in drinking water remains a major public health problem. Exposure to As may lead to degenerative peripheral vascular diseases. The purpose of this study is to clarify the role of As in modulating cell proliferation and in vitro angiogenesis in human umbilical vein endothelial cells (HUVECs) and to scrutinize the contributing factors of these events. The results revealed that lower concentrations (up to 1 μM) of sodium arsenite stimulated HUVEC cell growth. An in vitro angiogenesis assay indicated that low concentrations of As increased vascular tubular formation, which was abrogated by hemoglobin, a potent nitric oxide scavenger. In contrast, higher concentrations of As (>5 μM) revealed cytotoxicity and inhibition to angiogenesis. We also demonstrated that lower concentrations of As upregulated the expression of constitutive nitric oxide synthase (NOS3) at both transcriptional and translational levels and that lower concentrations of As implicated a modulatory role in vascular endothelial growth factor (VEGF) expression. In addition, low concentrations of As (<1 μM) increased von Willebrand Factor (vWF) antigen expression, whose elevation paralleled the onset of angiogenesis and was considered an early indicator of endothelial activation in tumor metastasis. VEGF and basic fibroblast growth factor can synergistically upregulate the vWF gene expression. Therefore, we conclude that the treatment of HUVECs with As leads to cell proliferation and activation, which preferentially enhances angiogenesis in vitro, possibly via the VEGF−NOS signaling pathway. The molecular mechanism(s) by which As facilitates angiogenesis remains to be elucidated.

A blue electroluminescent polymer, poly(biphenylenevinylene) derivative containing a bulky fluorenyl group, was prepared by the nickel-catalyzed coupling reaction. The structure and properties of the polymer, PBPHFV, were analyzed by various spectroscopic methods. The obtained polymer had good solubility and thermal stability. The polymer film showed maximum absorption and emission peaks at 370 and 485 nm, respectively. A blue electroluminescence (λmax = 465 nm) was obtained with intensities of 4116 cd/m² when the light-emitting diodes of ITO/PEDOT/PBPHFV/LiF/Al were fabricated. The maximum efficiency of the devices was 0.22 lm/W with a turn-on voltage of 4.3 V. With the optimum ratio of PBPHFV to PVK as 1:5, the luminance and efficiency of the devices reached up to 9342 cd/m² and 1.66 lm/W, respectively.

Soil anchors are commonly used as foundation systems for structures requiring uplift resistance, such as transmission towers, or for structures requiring lateral resistance, such as sheet pile walls. To date, the design of these anchors has been largely based on empiricism. This paper applies numerical limit analysis to rigorously evaluate the stability of vertical and horizontal strip anchors in undrained clay. Rigorous bounds on the ultimate pull–out capacity are obtained by using two numerical procedures that are based on finite element formulations of the upper and lower bound theorems of limit analysis. These formulations follow standard procedure by assuming a rigid perfectly plastic clay model with a Tresca yield criterion, and generate large linear programming problems. By obtaining both upper and lower bound estimates of the pull–out capacity, the true pull–out resistance can be bracketed from above and below. Results are presented in the familiar form of break–out factors based on various soil strength profiles and geometries, and are compared with existing numerical and empirical solutions.

Abstract:  In this paper, some practical aspects of the finite element implementation of critical state models are discussed. Improved automatic algorithms for stress integration and load and time stepping are presented. The implementation of two generalized critical state soil models, with one described first in this paper and the other recently published elsewhere, is discussed. The robustness and correctness of the proposed numerical algorithms are illustrated through both coupled and uncoupled analyses of geotechnical problems.

It is well established that severe numerical difficulties may arise when the displacement finite element method is used to analyse the behaviour of incompressible solids and this is particularly true for axisymmetric problems. These numerical difficulties are caused by excessive kinematic constraints and are reflected by strong oscillations in the calculated stress distribution and overestimations of collapse loads. The purpose of this paper is to present new displacement finite element formulations which are particularly suitable for axisymmetric analysis of incompressible materials. A direct comparison is made of the performance of various displacement finite elements in the analysis of elastic or plastic incompressible materials under axisymmetric loading conditions. Particular attention is focused on the performance of various axisymmetric displacement elements in predicting the stress field of incompressible or nearly incompressible materials. Copyright © 2000 John Wiley & Sons, Ltd.

A complete shakedown assessment of pavement behavior under repeated loading requires a shakedown load analysis as well as a displacement evaluation. Both load and displacement bounding calculations at shakedown are presented, and the pavement subjected to repeated loading is analyzed as a plane strain problem. The proposed shakedown load formulation is verified by using numerical results for a homogeneous isotropic half space. To illustrate the relevance of the numerical formulations, the numerically determined residual stresses are compared with available experimental data. The variation of shakedown loads with different material properties for two-layered pavements is investigated in detail. The results of permanent displacement bounds are presented and compared with the displacement finite element calculation. Simple design charts for the layered pavements are presented.

This paper applies numerical limit analysis to evaluate the undrained bearing capacity of a rigid surface footing resting on a two-layer clay deposit. Rigorous bounds on the ultimate bearing capacity are obtained by employing finite elements in conjunction with the upper and lower bound limit theorems of classical plasticity. Both methods assume a perfectly plastic soil model with a Tresca yield criterion and generate large linear programming problems. The solution to the lower bound linear programming problem is obtained by modelling a statically admissible stress field, whereas the upper bound problem is solved through modelling a kinematically admissible velocity field. Results from the limit theorems typically bracket the true collapse load to within approximately 12%, and have been presented in the form of bearing capacity factors based on various layer properties and geometries. A comparison is made between existing limit analysis, empirical and semi-empirical solutions. This indicates that the latter can overestimate or underestimate the bearing capacity by as much as 20% for certain problem geometries. Dans cet exposé, nous servons d'analyses limites numériques pour évaluer la capacité porteuse non drainée d'une assise à surface rigide reposant dur un dépöt argileux à deux couches. On obtient des limites rigoureuses pour la capacité porteuse ultime en employant des é1éments finis en conjonction avec les théorèmes de limite à borne supérieure et inférieure de la plasdcité classique. Les deux méthodes supposent un modéle de sol parfaitement plastique avec un critère d'élasdcité Tresca et entraïnent de gros problèmes de programmation linéaire. On obtient la solution au problème de programmation linéaire de limite inférieure en faisant la maquette d'un champ de contrainte admissible en statistique tandis que le problème de limite supérieure est résolu par la mise en maquette d'un champ de vélocité admissible en cinétique. De manière typique, les résultats de théorèmes limites cernent dans une marge d'environ 12% la vraie charge d'affaissement et sont présentés sous forme de facteurs de capacité porteuse basés sur les propriétés et géométries des diverses couches. Nous comparons les analyses limites existantes, les solutions empiriques et les solutions semiempiriques. Cette comparaison indique que ces dernières peuvent surévaluer ou sousestimer de 20% la capacité porteuse dans le cas de certaines géométries à problème.

Abstract The immune function of peripheral mononuclear cells (MNC) in patients with endemic arsenic-induced Bowen’s disease (BD) was investigated. Many cytokines and immune-related factors were determined in the present study. Interleukin-1β and TNF-α production was used as an indicator of monocyte/macrophage function. Il-2 and sIL-2R production was used as an indicator of lymphocyte activation. The release of sCD4 and sCD8 was used as an indicator of activation of respective T-cell subpopulations. Production of IFN-γ and IL-2 reflected the cellular effector function of helper T-cells type 1. In vivo cell-mediated immunity was also assessed by estimation of the percentage of T-cells in peripheral blood MNC and the nonspecific delayed-type hypersensitivity (DTH) response to 2,4-dinitrochlorobenzene (DNCB). Both assays revealed depressed cell-mediated immunity in BD. Compared with healthy controls, spontaneous and PHA-induced IFN-γ and TNF-α production was significantly decreased in BD whereas spontaneous release of IL-2, sCD4 and sCD8 was significantly increased. Although PHA stimulation increased IL-2 release, the expression of IL-2R α and β chains and the release of sIL-2R were not proportionately increased in BD. In addition, IL-2-mediated [: 3H]-thymidine incorporation by MNC in patients with BD was significantly decreased. These findings suggest that the defective cell-mediated immune function in BD is due to impairment of membrane IL-2R expression in lymphocytes after stimulation.:

The pressuremeter test has proved to be a useful tool for geotechnical engineers to determine the in situ properties of soils. However, results indicate that the strength values derived from pressuremeter tests are often quite different from those obtained from good laboratory tests and other in situ tests. It is believed that a major part of this disagreement may be due to the influence of pressuremeter geometry. This is because, in most analyses, the pressuremeter is assumed to be infinitely long, although commercial pressuremeters are of finite length. Therefore, it is necessary to investigate the possible effect of the finite pressuremeter length on soil parameters derived from the tests. A two-dimensional axisymmetric finite-element analysis was used to simulate pressuremeter tests. It was found that the finite pressuremeter length has a significant effect on derived soil properties. Experimental studies on the effect of a finite pressuremeter length reported in the literature are not sufficiently comprehensive to reach a definite conclusion about the effect of pressuremeter geometry on derived soil properties. In the present study, therefore, a large number of pressuremeter tests with four different length/ diameter ratios (LID = 59 109 159 20) were conducted in a 1 m × 1 m calibration chamber located at the University of Newcastle, Australia. Based on the results of those laboratory pressuremeter tests, experimental correlations are presented which can be readily used in practice to account for the effect of pressuremeter geometry on the derived soil properties. ľessai au pressiométre est un outil utile pour les ingé;nieurs géotechniques car it leur permet ďobtenir in situ les propriétés des sols. Cependant, les résultats indiquent que les valeurs de résistance dérivées de cet essai sont souvent triés différentes de celles venant de bons essais en laboratoire et autres tests in situ. On estime que cette diff6rence, dans une grande partie, pent âtre due á la géométrie du pressiométre. Car dans la plupart des analyses, on suppose que le pressiométre a une longueur infinie, alors que les pressiométres commerciaux ont une longueur limitée. Il est donc n6cessaire ďétudier les effete possibles de la longueur des pressiométres sur les paramétres du sol dérivés de ces essais. Sur le plan éorique, une analyse d'616ments finis axisymétrique en deux dimensions a été utilisée pour simuler les essais de pressiométre. On en a conclu que la longueur limit&cute;e du pressiométre avait un effet significatif sur les propriétés du sol qui en étaient dérivées.&acuteE;tudes expérimentales surˇeffet de la longueur limitée des pressiométres dans la litterature ne sont pas assez complétes pour nous permettre &caon;arriver á une conclusion déinitive surˇeffet de la géométrie des pressiométres sur les propriétés du sol qui en sont dérivées. Dans cette étude, nous avons mené de nombreux essais avec des pressiométres de 4 longueurs différentes et de rapports longueur/diamétre (LID) de 5, 109 159 20 dans une chambre de calibrage de 1 m × 1 m, située á ˇuniversité de Newcastle en Australie. En nous basant sur les résultats de ces essais en laboratoire, nous présentons des corrélations expérimentales qui peuvent être facilement utilisées dans la pratique pour expliquerˇeffet de la géométrie des pressiométres sur les propriétés de sol qui en sont dérivées.

The paper presents a new unloading analysis for pressuremeter tests in sands. The analysis is based on a strain-hardening (or softening) plasticity model in which the angles of friction and dilation are assumed to be a function of the state parameter. A series of numerical analyses using the state parameter-based constitutive soil model suggest that there is a linear correlation between the slope of the pressuremeter unloading curve, when plotted on logarithmic scales, and the initial state parameter. As a result, the initial state parameter, and therefore the friction angle of the soil, can be deduced from the measured slope of the pressuremeter unloading curve. The validity of this new unloading analysis has been confirmed with the results of a number of field and laboratory pressuremeter tests. L'article présente une nouvelle méthode permettant d'analyser la phase de déchargement d'essais pressiométriques réalisés dans du sable. Cette analyse est fondée sur un modéle en plasticité, avec écrouissage durcissant (on ra-doucissant), dans lequel on suppose que l'angle de frottement et la dilatation s'expriment en fonction du paramétre d'&aute;tat. Une série d'analyses numériques utilisant un modéle constitutif de sol fondé sur le paramétre de'état montre qu'il existe une corrélation linéaire entre la pente de la courbe de déchargement d'un essai pressiométrique, tracée dans un repére bilogarithmique, et le paramétre de'état initial. Par conséquent, il est possible de calculer, par mesure directe de la pente de la courbe de déchargement, le paramétre d'état initial, et donc l'angle de frottement interne du sol. Cette nouvelle méthode d'analyse a été validée par de nombreux essais pressiométriques réalisés sur le terrain et en laboratoire.

Objective:To investigate whether interleukin-13 (IL-13) can affect arachidonic acid metabolism and phagocytic activity of normal human polymorphonuclear neutrophils (PMN).¶Methods:Normal human PMN (1 × 106cells/ml) were incubated with different concentrations of IL-13 (0.1–10 ng/ml) for a variety of times (30–120 min). Phagocytosis and intracellular cyclooxygenase-2 (COX-2) were detected by flow cytometry. The expression of COX-1 and COX-2 mRNA was detected by RT-PCR. The concentration of PGE2in the PMN cultured supernatants was determined by EIA.¶Results:We found that IL-13 at an optimal concentration of 1 ng/ml significantly enhanced COX-2 gene expression and PGE2production (121.57 ± 22.17 pg/ml in IL-13 stimulation vs. 73.16 ± 11.72 pg/ml in controls) by PMN. In addition, IL-13 stimulated PMN phagocytosis via increased complement receptor type 1 (CR1) and type 3 (CR3), but not IgG Fcγ receptor type 3 (FcγRIII). The cytoplasmic neutral esterase activity of PMN was also enhanced by IL-13 stimulation for 24 h.¶Conclusions:These results suggest that IL-13 can stimulate PMN and modulates the inflammatory reactions via the cyclooxygenase pathway.

One of the most economically-viable processes for the bioconversion of many types of lignocellulosic wastes is represented by edible mushroom cultivation. Lentinula edodes, Volvariella volvacea and Pleurotus sajor-caju are three important commercially cultivated mushrooms which exhibit varying abilities to utilise different lignocellulosics as growth substrate. Examination of the lignocellulolytic enzyme profiles of the three species show this diversity to be reflected in qualitative variations in the major enzymic determinants (i.e. cellulases, ligninases) required for substrate bioconversion. For example, L. edodes, which is cultivated on highly lignified substrates such as wood or sawdust, produces two extracellular enzymes which have been associated with lignin depolymerisation in other fungi, (manganese peroxidase and laccase). Conversely, V. volvacea, which prefers high cellulose-, low lignin-containing substrates produces a family of cellulolytic enzymes including at least five endoglucanases, five cellobiohydrolases and two ß-glucosidases, but none of the recognised lignin-degrading enzymes.

A new polyimide, PI(6FDA/ep-AHHFP), containing an epoxy group was synthesized by the reaction of epichlorohydrin with PI(6FDA/AHHFP), which was prepared from 4,4‘-(1,1,1,3,3,3-hexafluoro-2-propylidene)diphthalic anhydride (6FDA) and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (AHHFP) in the presence of benzyl(trimethyl)ammonium chloride at 110−120 °C. This polyimide having an epoxy group is highly soluble in most common solvents. Photochemical reactivity of PI(6FDA/ep-AHHFP) was examined in the presence of diphenyliodonium hexafluoroarsenate as an acid generator. The conversion and the curing rate were determined by the absorbance change in the IR band at 905 cm^-1 for the epoxy group. The activation energy for cross-linking reaction of PI(6FDA/ep-AHHFP) was found to be ~6 kJ/mol. The reaction radius of an acid in PI(6FDA/ep-AHHFP) containing diphenyliodonium hexafluoroarsenate as a photoacid generator was determined to be about 19−30 Å in the chemical amplification process when heated for 5−40 min at 50−195 °C. The quantum yield for cross-linking of PI(6FDA/ep-AHHFP), Φgel, obtained from the characteristic curve was 3.0. The sensitivity, Dgel, and contrast, γ, after postcure at 100 °C for 30 min were 4.8 × 10^-10 einstein cm^-2 and 5.7, respectively. The quantum yield for cross-linking, ΦGPC, was determined to be 2.6 from gel permeation chromatography measurements.

To study the short- and long-term effects of pinealectomy on the level of retinal melatonin, male rats adapted to a photoperiod of 12 h light: 12 h darkness (with lights on at 06.00 h) were pinealectomized. In the short-term experiment, the rats were decapitated 1 week after pinealectomy. In the long-term experiment, 1 month was allowed for recovery. Melatonin was extracted from retinae and quantified by radioimmunoassay. A diurnal rhythm of retinal melatonin was found to persist after pinealectomy in both experiments. An increase in retinal melatonin was demonstrated 1 month after pinealectomy, indicating a compensatory effect on melatonin in the retinae of pinealectomized rats. Thus, biosynthesis of melatonin in the retina may be modulated through a negative feedback system.

The volatile blend emitted by calling virgin beet armyworm females was collected and analyzed by capillary gas chromatography and mass spectrometry. Five compounds were detected and identified in this blend: (Z)-9-tetradecenyl acetate, (Z)-9-tetradecen-l-ol, (Z,E)-9,12-tetradecadienyl acetate (Z,Z)-9,12-tetradecadienyl acetate, and (Z)-l 1-hexadecenyl acetate. They were emitted in a ratio of 47.9 :4.0:40.2 :6.5 : 1.7, respectively. This five-component blend and several other blends with one or more components deleted were formulated on rubber septa to release the components in about the same ratios as the females. Field tests of these formulations in bucket traps indicated that a blend of (Z)-9 tetradecen-1-ol, (Z,E)-9,12-tetradecadienyl acetate, and (Z)-l 1-hexadecenyl acetate was most effective for trapping beet armyworm males and that (Z)-9-tetradecenyl acetate actually decreased trap captures. Blends that did not contain both (Z)-9-tetradecen-l-ol and (Z,E)-9,12-tetradecadienyl acetate were ineffective as trap baits.

Pollinia of Cymbidium goeringii (Orchidaceae) were examined at a young stage (approx. 2 weeks before anthesis) and at anthesis using transmission electron microscopy, computer-assisted serial reconstruction and quantitative cytology. At the young stage, the generative cell (GC) has a spherically shaped main body with a large nucleus and 1 to 4 cytoplasmic extensions (up to 10 µm long) physically associated with a groove on one side of the vegetative nucleus (VN). By anthesis, some GCs lose their cytoplasmic extensions, becoming spherical. The GC surface becomes highly wrinkled, the distance between the GC and the VN increases and the two may separate completely. Enucleated cytoplasmic bodies (ECBs) are apparently generated by the GC, as evidenced by their similar ultrastructural appearance and distribution near the GC. ECBs are likely produced from two sites: the GC surface and the tips of cytoplasmic extensions of the GC. Vesicle-containing bodies (VCBs) may be generated from the lateral surface of the GC and may also represent a degeneration stage of ECBs, finally fusing with lipid bodies. Heritable organelles are rare and usually absent in the GC of Cymbidium: 0.176 mitochondria and 0.0042 plastids per GC were observed at the young stage and no mitochondria and 0.019 plastids at anthesis. Of 16 cellular parameters examined during GC development, all decreased with the exception of the surface area and volume of ECBs/ VCBs (which remained stable) and GC vacuoles (which increased). Significant decreases in 11 parameters presumably relate to dehydration of the pollen and male cytoplasmic diminution.

In order to evaluate the prevalence and multiple risk factors of arsenic-induced skin cancer among residents in Taiwanese villages in which chronic arseniasis is hyperendemic, a total of 1571 subjects aged 30 or more years were recruited between September 1988 and March 1989. All of them were interviewed personally by a public health nurse using a structured questionnaire, and 1081 interviewed study subjects, including 468 men and 613 women, participated in physical examination, giving a participation rate of 68.8%. The overall prevalence of skin cancer was as high as 6.1%, showing an increase with age in both men and women. There was a significant dose-response relation between skin cancer prevalence and chronic arsenic exposure as indexed by duration of residence in the endemic area, duration of consumption of high-arsenic artesian well water, average arsenic exposure in parts per million (p.p.m.) and cumulative arsenic exposure in p.p.m.-years. Chronic carriers of hepatitis B surface antigen with liver dysfunction had an increased prevalence of skin cancer. Undernourishment, indexed by a high consumption of dried sweet potato as a staple food, was also significantly associated with an increased prevalence of arsenic-induced skin cancer. All these risk factors remained statistically significant in the multiple logistic regression analysis. Consistent with animal experiments, the findings imply that liver function and nutritional status may affect the metabolism of inorganic arsenic and the development of subsequent skin cancers.

Abstract: A basal cell carcinoma (BCC) cell line (BCC-1/KMC) has recently been successfully established from a patient. The production of interleukin-1· (IL-1·), IL-1‚, IL-6 and IL-8 was assessed in comparison with that of cultured normal keratinocytes. The mRNA expression of these cytokines was measured by a reverse transcriptase-polymerase chain reaction (RT-PCR) method and the protein production by an ELISA. The cultured BCC cells spontaneously secreted more IL-6 and IL-8 but less IL-1 than the keratinocytes after culture for 24 h at 37° C. It is suggested that the increased expression of IL-6 and IL-8 may indicate the transformation of normal keratinocytes to locally aggressive BCC.

Summary The organization of the sperm cells and vegetative nucleus (male germ unit) ofNicotiana tabacum was examined 18 h after semivivo pollination using transmission electron microscopy, computerassisted serial section reconstruction and quantitative cytology. Based on a measurement of 11 cellular parameters in nine reconstructed sperm cell pairs, there are no statistically significant differences between the two cells. The Svn is characterized by a strapshaped cytoplasmic extension that is physically associated with the surface of the vegetative nucleus. The nucleus is located adjacent to the sperm crosswall, with sperm organelles being distributed between the nucleus and the extension. The Sua is a tapered cell with cytoplasmic areas at both poles and deep axial invaginations near the crosswall. This cell has a centrally-located nucleus and a largely polar distribution of organelles. Three mechanisms for cytoplasmic diminution were observed that appear to contribute actively to the loss of cytoplasmic volume and organelles: (1) enucleated cytoplasmic body production in the Sua; (2) vesiculation at the tip of the cytoplasmic projection of the Svn; and (3) vesicle-containing body accumulation in the periplasm of both the Svn and Sua.

In flowers grown at warm temperatures in environmental chambers and at cooler temperatures in the greenhouse, eight parameters of the sperm-cell organization of Nicotiana tabacum were examined during sperm cell maturation using serial ultrathin sectioning, transmission electron microscopy and quantitative cytology. Despite employing the same seed source, and similar soil and nutrient conditions, the surface area and volume of the cell, the nucleus and the chondriome were larger in flowers grown in growth chambers under warmer controlled conditions, whereas the number of plastids appeared to be the same, or slightly higher, in flowers grown under cooler greenhouse conditions. These results suggest that environmental conditions may influence the quantity of cytoplasmic organelles, including mitochondria and plastids, thus potentially influencing the likelihood of male cytoplasmic inheritance.

Prostaglandin E2 (PGE2) at concentrations more than 1×10−8M markedly suppressed the cell proliferation and release of soluble molecules of interleukin-2 receptor (sIL-2R), CD4 (sCD4) and CD8 (sCD8) from phytohemagglutinin (PHA)-stimulated normal human mononuclear cells (MNC) in a dose-related manner. To further elucidate the subcellular mechanism of the inhibitory effect of PGE2 on PHA-stimulated MNC, intracellular concentration of glutathione (GSH) in PHA-stimulated MNC was sequentially measured from day 1 to day 3 by enzymic method. Furthermore, the effect of PGE2 on nuclear DNA including DNA strand breaks in alkali treatment and DNA fragmentation (apoptosis) of PHA-stimulated MNC were also measured. We found intracellular GSH levels were significantly decreased in the early stage of lymphocyte activation (day 1), but no evidence of increased DNA stand breaks or apoptotic process appeared in 3-day culture. In addition, butathione sulfoximine (a specific GSH inhibitor) and dibutyryl cyclic AMP also exhibited both proliferation inhibition and GSH-decreasing effect on PHA-stimulated MNC as well as PGE2. These results suggest that the immunosupressive effect of PGE2 is mediated by the decreased generation of intracellular GSH, but not by the increased DNA strand breaks or apoptotic mechanism in the cells.

Cerebrospinal fluid (CSF) from patients with a variety of central nervous system (CNS) disorders was assayed for cytokines, prostaglandins, and autoantibodies. CSF interleukin-6 (IL-6) in patients with CNS infection (374.24 ± 92.61 pg/mL) and neuropsychiatric systemic lupus erythematosus (NP-SLE) (71.40 ± 5.89 pg/mL) were significantly higher than in patients with CNS inflammation (33.92 ± 29.36 pg/mL) or controls (non-inflammatory CNS diseases) (4.35 ± 3.00 pg/mL). Interleukin-1β, interferon α, and tumor necrosis factor α were undetectable in these samples: CSF prostaglandin E2 (PGE2) also exhibited similar patterns as IL-6. CSF immunoglobulin G (IgG) in patients with NP-SLE (8.84 ± 1.80 mg/dL) was much higher than in patients with CNS infection (4.65 ± 3.09 mg/dL), CNS inflammation (2.54 ± 1.24 mg/dL), or controls (2.11 ± 1.03 mg/dL). CSF autoantibodies against calf thymus antigens were present in patients with NP-SLE but not in patients with CNS infection as demonstrated by immunoblot. These results suggest that high IL-6 and PGE2 in CSF favors the diagnosis of CNS infection, while modestly elevated IL-6, high IgG, and autoantibodies against calf thymus antigens in CSF are the features of NP-SLE.

Melatonin was extracted by chloroform from the retina of the rat and measured by radioimmunoassay. In rats housed under a régime of 12 h light: 12 h darkness, melatonin content in the retina, like that in the pineal, serum and brain tissue, was high from midway through the dark to early in the period of light, and low from half-way through the light period to early in the period of darkness. A similar result was found in a second experiment. The existence of a diurnal rhythm of melatonin in the retina of rats as observed in this study is consistent with the suggestion that melatonin may regulate the diurnal rhythm of eye pigmentation in vertebrates.

In our previous studies, we found that polyclonal anti-double-stranded DNA antibodies (anti-dsDNA) purified from sera of patients with active systemic lupus erythematosus (SLE) were cytotoxic to cultured rat glomerular mesangial cells (RMC) through an apoptotic mechanism. In order to determine whether these nephritogenic antibodies affect the expression of apoptosis-related genes in the tissues, the expression of Fas, p53, c-myc, and bcl-2 genes in the kidneys and livers of 12-week-old normal BALB/c and autoimmune MRL-lpr/lpr mice was detected by a reverse transcription-assisted polymerase chain reaction (RT-PCR). We found the mRNA of the four genes were expressed in the tissues of the normal mice. In contrast, decreased expression of the four genes in the kidney and absent expression of bcl-2 in the liver of the lpr mice were noted. Interestingly, RMC only expressed p53 and c-myc, but not Fas or bcl-2, in culture. The purified polyclonal anti-dsDNA dose-responsively (50-200 IU/ml) suppressed the 3H-thymidine incorporation of RMC after incubation for 48h. However, the incubation of 100 IU/ml of anti-dsDNA with RMC for 4h did not affect the expression of these apoptotic genes. The results suggest that anti-dsDNA induce RMC apoptosis via an unidentified mechanism different from Fas, c-myc or p53 pathway. Chia-Li Yu, Department of Medicine & Institute of Clinical Medicine, Veterans General Hospital-Taipei, National Yang-Ming University. #201 Section 2, Shih-Pai Raod, Taipei, Taiwan 11217, ROC

The purpose of this paper is to present a simple, unified critical state constitutive model for both clay and sand. The model, called CASM (Clay And Sand Model), is formulated in terms of the state parameter that is defined as the vertical distance between current state (v, p′) and the critical state line in v–ln p′ space. The paper first shows that the standard Cam‐clay models (i.e. the original and modified Cam‐clay models) can be reformulated in terms of the state parameter. Although the standard Cam‐clay models prove to be successful in modelling normally consolidated clays, it is well known that they cannot predict many important features of the behavior of sands and overconsolidated clays. By adopting a general stress ratio‐state parameter relation to describe the state boundary surface of soils, it is shown that a simple, unified constitutive model (CASM) can be developed for both clay and sand. It is also demonstrated that the standard Cam‐clay yield surfaces can be either recovered or approximated as special cases of the yield locus assumed in CASM.

A solution method is described and applied for treating non-similar thermal boundary layers. The solutions are locally autonomous (that is, independent of information from other streamwise locations) and are found by solving quasi-ordinary differential equations of the similarity type. All non-similar terms appearing in the conservation equations are retained without approximation, and only in derived subsidiary equations are terms selectively neglected. The accuracy of the results can be appraised from comparisons internal to the method itself. Thermal boundary-layer non-similarity arising both from velocity-field, non-similarity and from streamwise variations of surface temperature are analyzed. Numerical results for the surface heat transfer and for the boundary-layer temperature distribution are presented for various physical situations.

An analysis is made of the rate of the mass flow through a vacuum seal separating two rarefied gas environments. The determination of the mass throughflow characteristics involves the formulation and solution of a coupled system of six integral equations. The formulation is performed using the methods of kinetic theory. Numerical solutions are carried out for a wide range of values of the seal geometrical parameter. Mass flow results evaluated from these solutions are presented graphically. In addition, representative distributions of the mass fluxes at the participating surfaces are given.