bluuebunny/crossref_metadata_2025 huggingface dataset:
Therapeutic approaches to superantigen‐based diseases: a review
Authors: Hong‐Geller Elizabeth , Gupta Goutam
Published: April 2003

Superantigens secreted by the bacterial pathogen Staphyloccocus aureus are extremely potent toxins that overstimulate the host immune system by binding to the MHC class II and T cell receptors and activating a large population of T cells. Superantigen infection has been shown to be the causative agents in acute diseases, food poisoning and toxic shock syndrome, and in more chronic conditions such as inflammatory skin diseases. In addition to the toll on public health, S. aureus superantigens also represent a potential biothreat to our national security. To address these risks, a number of different therapeutic strategies have been developed that target different aspects of the pathogenic mechanism of S. aureus and superantigen infection. These therapies, which encompass strategies as diverse as production of neutralizing antibodies, inhibitory peptide/receptor design and blockage of superantigen gene transcription, are being tested for treatment of established S. aureus infections in pre‐ and post‐exposure scenarios. In this review, we will describe these different strategies and their efficacies in inhibition of superantigen‐induced effects in the host, and present the future outlook for successfully producing therapies for superantigen‐based disease. Copyright © 2003 John Wiley & Sons, Ltd.
Involvement of c‐jun N‐terminal kinase activation in 15‐deoxy‐δ12,14‐prostaglandin J2–and prostaglandin A1–induced apoptosis in AGS gastric epithelial cells
Authors: Liu Jean‐Dean , Lin Shyr‐Yi , Ho Yuan‐Soon , Pan Shiann , Hung Ling‐Fang , Tsai Shu‐Huei , Lin Jen‐Kun , Liang Yu‐Chih
Published: April 2003

Cyclopentenone prostaglandins (CyPGs), derivatives of arachidonic acid, have been suggested to exert growth‐inhibitory activity through peroxisome proliferator‐activated receptor (PPAR)‐dependent and ‐independent mechanisms. Here we examined various eicosanoids for growth inhibition and found that the terminal derivative of prostaglandin (PG) J2 metabolism, 15‐deoxy‐Δ12,14‐PGJ2 (15d‐PGJ2), and PGA1 markedly inhibited the growth and induced apoptosis in AGS gastric carcinoma cells. There were no significant increases in cell death and DNA‐fragmentation in the cells with overexpression of PPARα or PPARγ, indicating the possibility that 15d‐PGJ2 and PGA1 induced apoptosis through PPAR‐independent pathway. Moreover, 15d‐PGJ2 and PGA1 activated the c‐jun N‐terminal kinase (JNK) and caspase‐3 activity in dose‐ and time‐dependent manners. To examine further the role of JNK signaling cascades in apoptosis induced by 15d‐PGJ2 and PGA1, we transfected dominant‐negative (DN) mutants of JNK plasmid into the cells to analyze the apoptotic characteristics of cells overexpressing DN‐JNK following exposure to 15d‐PGJ2 and PGA1. Overexpression of DN‐JNK significantly repressed both endogenous JNK and caspase‐3 activity, and subsequently decreased apoptosis induced by 15d‐PGJ2 and PGA1. These results suggested that CyPGs, such as 15d‐PGJ2 and PGA1, activated JNK signaling pathway, and that JNK activation may be involved in 15d‐PGJ2‐ and PGA1‐induced apoptosis. © 2003 Wiley‐Liss, Inc.
Some Transition Metal Salts of 4,6‐Dinitrobenzofuroxan: Synthesis, Characterization and Evaluation of Their Properties
Authors: Shinde P. D. , Mehilal  , Salunke R. B. , Agrawal J. P.
Published: April 2003

Chromium, Iron and Copper salts of 4,6‐dinitrobenzofuroxan have been prepared by reacting sodium salt of 4,6‐dinitrobenzofuroxan with chromium nitrate nonahydrate, ferric nitrate nonahydrate and cupric nitrate trihydrate, respectively. The compounds have been characterized by elemental analysis, spectral data (IR and NMR) and metal content. Some properties including thermal and explosive behaviour of these compounds have been investigated and reported. Further, these molecules have also been investigated in composite propellants as burn‐rate modifiers. The preliminary data suggest that iron salt of 4,6‐dinitrobenzofuroxan is better than ferric oxide, generally used as a burn‐rate modifier for hydroxy‐terminated polybutadiene (HTPB) based composite propellants.
A proposal for the measurement of boundary layer temperature gradient using Doppler lidar
Authors: Sandiford K. J. , Collier C. G.
Published: April 2003

A technique of retrieving temperature gradient in the atmospheric boundary layer from measurements of signal to noise ratio derived from a CO2pulsed Doppler infrared lidar is proposed. Copyright © 2001 Royal Meteorological Society.
Isolation of rat Kupffer cells: a combined methodology for highly purified primary cultures
Authors: Valatas V. , Xidakis C. , Roumpaki H. , Kolios G. , Kouroumalis E.A.
Published: April 2003

We report a four‐step procedure that optimizes the methodology for isolation of highly purified rat Kupffer cells (KC). We combined the previously reported techniques of enzymatic tissue treatment, density gradient centrifugation, centrifugal elutriation and selective adherence. ED‐2 immunophenotyping and non‐specific esterase histochemistry were used for cell identification. This combination resulted in a satisfactorily high yield of 80–100×106KCs per liver, over 95% positive for ED‐2 and 98% viable cells. Cultures of isolated KCs were functionally intact and exhibited a concentration and time‐dependent LPS‐induced TNF‐α and nitric oxide production.
CR2 units of CR2 complexes are possibly associated with nucleophilic agents through reactive covalent links
Authors: Di Certo Maria Grazia , Faggioni Alberto , Barile Giuseppe
Published: April 2003

The human complement receptor type 2 (CR2/CD21), a transmembrane glycoprotein, associates with a variety of surface antigens and proteins in the cell membrane. We examined the possibilities that the CR2 units of CR2 complexes are associated through internal covalent links reactive with nucleophilic agents, e.g. H2O or methylamine, and that CR2‐positive cells process anti‐CR2 monoclonal antibodies (MoAbs). Data from immunoblotting and cytofluorimetry with CR2‐binding site‐specific MoAbs show that: (i) CR2‐positive Raji cells release soluble CR2 isoforms into the medium when incubated in phosphate buffered saline; (ii) despite affecting the detection of one soluble CR2 isoform, methylamine treatment of soluble CR2 allows the detection of another of its isoforms; (iii) limited pre‐treatment of cells with methylamine reveals a more heterogeneous CR2‐positive cell population or enhances the detection of CR2; (iv) cell treatment with CR2‐binding site‐specific MoAbs enhances the detection of CR2 isoform(s). The data suggest that CR2 is shed mainly as a soluble CR2 complex, in which the CR2 units link covalently and react with nucleophilic agents. Raji cells may process bound fragments (145 kDa) that are recognised by and become bound by anti‐CR2 MoAb.
MODELLING THE INFLUENCE OF IRRIGATION ON THE POTENTIAL YIELD OF TEA (CAMELLIA SINENSIS) IN NORTH-EAST INDIA
Authors: PANDA R. K. , STEPHENS W. , MATTHEWS R.
Published: April 2003

This study reports the results of model simulations of the potential yield of tea in north-east India. The CUPPA-Tea model, developed using data from a high-altitude site close to the equator in East Africa, was validated against the yield data from irrigation experiments conducted on contrasting soil types at Siliguri and Tezpur in the tea growing region of north-east India. The close correspondence between observed and predicted yield and yield distribution suggests that the model is applicable in north-east India. The model was used to simulate the yield response of tea to drought and irrigation using daily weather data for seven years (1983–89) at Siliguri and 14 years (1974–85) at Tezpur. On a clay loam soil at Siliguri, with an available water capacity of about 200 mm m−1, the predicted mean reduction in yield was 1.5 kg ha−1 for each 1 mm reduction in evapotranspiration. However, there appeared to be no reduction in evapotranspiration until the soil water deficit reached about 240 mm. By contrast, at Tezpur on loamy sand, with an available water capacity of about 100 mm m−1, evapotranspiration was reduced once soil water deficits exceeded about 85 mm. There was then a mean reduction in yield of 2.2 kg ha−1 for each 1 mm reduction in evapotranspiration. At both sites, even when soil water deficits were not limiting, the predicted year-to-year variation in yields was about 500 kg ha−1. The results highlight the soil-related differences in response to irrigation and the benefits of using process-based simulation models to investigate the potential yields over long periods.
GROUPING LOCATIONS FOR EFFICIENT CASSAVA EVALUATION IN MALAWI
Authors: MKUMBIRA J. , MAHUNGU N. M. , GULLBERG U.
Published: April 2003

Cassava, a crop widely adapted in the tropics, has the important attribute of withstanding adverse environmental conditions better than do many other staple crops. The performance of an individual genotype, however, is influenced by the environment in which it grows. In Malawi, the heterogeneity of agro-ecologies requires the cumbersome and costly assessment of new cassava genotypes at many sites. This study was conducted, therefore, to test the feasibility of selecting only a few locations for cassava evaluation that would be representative of all the agro-ecologies in which cassava is grown in Malawi. Enormous environmental effects, largely contributed by the interaction between season and location, were manifested. Genotype×environment interaction, due largely to a third level interaction (genotype×season×location), was highly significant for all the traits studied. A principal component analysis scatter plot showed no particular grouping of environments, but a pair-wise comparison showed that some of the locations had limited genotype×environment interaction, indicating that it would be sufficient to use one of these sites for evaluating these traits. The value of the residual was often large, probably as an effect of environmental heterogeneity in the test sites. The authors conclude that cassava genetic improvement will continue to be slow if Malawi is used as a single breeding zone. They recommend a much finer grouping of the locations and the use of smaller plot sizes to allow more clones to be tested at more sites for the same cost. Locations may be selected for intensive cassava breeding work from those that give the best discrimination between genotypes while having insignificant genotype×environment interactions in a relatively large number of environments.
GABA and mood disorders
Authors: TAYLOR M. , BHAGWAGAR Z. , COWEN P. J. , SHARP T.
Published: April 2003

A γ-aminobutyric acid (GABA)-ergic theory of mood disorders was proposed by Emrich and colleagues (1980) following observations of the efficacy of the GABAergic anticonvulsant, valproate, in the treatment of mania. Since then, increasing biochemical and pharmacological evidence from animal and human studies has supported the hypothesis that mood disorders are associated with abnormalities in brain GABA function.
Age Patterns of Suicide
Authors: Alte da Veiga Francisco , Braz Saraiva Carlos
Published: April 2003

Summary: Relatively few studies have addressed age patterns of suicide using specifically designed and systematized approaches. Our main objective was to identify and characterize age patterns of suicide in Europe, both on cross-sectional and longitudinal perspectives, based on data comprising the two last decades of the 20th century. A second objective was to determine whether some analytical methods could be useful as complementary approaches to the traditional examination of age-specific rate curves. We identified and characterized four patterns: upward-sloping, convex, downward-sloping, and uniform. The first three reproduce patterns previously described, though we propose some modifications to the respective classification criteria. Longitudinally, pattern stability was found for most countries, but some notable exceptions were detected. From the computation of multiple-decrement life tables by European country, period, and gender, we derived cumulative distributions of age at death for suicide. The results indicate that this methodology is a useful tool, not only for describing and summarizing information, but, more importantly, for providing a better understanding of intrinsic features and complexities of the patterns. Finally, we discuss practical implications of the study in the context of previous theories linking age patterns of suicide to sociological and economic dimensions, and we raise a few questions and hypotheses to be addressed in future research.
Cytotaxonomy, morphology and molecular systematics of the Bioko form of Simulium yahense (Diptera: Simuliidae)
Authors: Post R.J. , Flook P.K. , Millest A.L. , Cheke R.A. , McCall P.J. , Wilson M.D. , Mustapha M. , Somiari S. , Davies J.B. , Mank R.A. , Geenen P. , Enyong P. , Sima A. , Mas J.
Published: April 2003

Cytotaxonomic analysis of the polytene chromosomes from larvae of the Simulium damnosum Theobald complex from the island of Bioko in Equatorial Guinea is reported, and a new endemic cytoform is described. Chromosomally this cytoform is close to both S. squamosum (Enderlein) and S. yahense Vajime & Dunbar, but is not identical to either. However, it is morphologically and enzymatically identical to S. yahense. The Bioko form was also found to differ from other cytoforms of the S. damnosum complex in West Africa in the copy number or RFLP pattern of several different repetitive DNA sequences. It is clear that the Bioko form is genetically distinct from other populations of the S. damnosum complex, and whilst it is closest to S. yahense, it shows features that suggest a high degree of geographical and genetic isolation. Such isolation is an important consideration in the assessment of the potential for onchocerciasis vector eradication on Bioko.
JORDANIAN QUANTUM SUPERALGEBRA Uh(osp(2/1))
Authors: AIZAWA N. , CHAKRABARTI R. , SEGAR J.
Published: April 2003

A quantum deformation of the Lie superalgebra osp(2/1) from the classical r-matrix including an odd generator is presented with its full Hopf algebraic structure. A class of deformation maps and the corresponding twisting elements, the interrelation between these twists, and the tensor operators are considered for the deformed osp(2/1) algebra. It is also shown that the Borel subalgebra of the universal enveloping algebra of the quantized osp(2/1) is self-dual.
MINIMAL NONSIMPLE SETS OF VOXELS IN BINARY IMAGES ON A FACE-CENTERED CUBIC GRID
Authors: GAU C. J. , KONG T. Y.
Published: April 2003

One can prove that a specified parallel thinning algorithm always preserves the topology of the input binary image by verifying that no iteration of that algorithm can ever delete a minimal non-simple ("MNS") set of 1's of an image. For binary images on a 3D face-centered cubic ("FCC") grid, we determine which sets of voxels can be MNS, and also determine which of those sets can be MNS without being a component of the 1's. These two problems are complicated by the fact that there are (at least) three reasonable ways of defining connectedness for sets of 1's and 0's in a binary image on an FCC grid, since one can: (a) use 18-connectedness for sets of 1's and 12-connectedness for sets of 0's; (b) use 12-connectedness both for sets of 1's and for sets of 0's; (c) use 12-connectedness for sets of 1's and 18-connectedness for sets of 0's. We solve the two problems in all three cases.

The analogous problems for binary images on Cartesian grids were first solved by Ronse (in the 2D case) and Ma (in the 3D case). However, our treatment of simple 1's and MNS sets is rather different from theirs, in that it is based on the attachment sets of 1's in binary images. This concept was introduced in an earlier paper [T. Y. Kong, "On topology preservation in 2-D and 3-D thinning," Int. J. Pattern Recognition and Artificial Intelligence9 (1995) 813–844] and we use the same general approach to MNS sets as was used there.

The voxels of an FCC grid are rhombic dodecahedra, which are rather more difficult to visualize and draw than the cubical voxels of a 3D Cartesian grid. An advantage of working with attachment sets is that such sets can be shown in a planar Schlegel diagram of a voxel, which is easy to draw.
ON TEXTURE CLASSIFICATION USING FRACTAL DIMENSION
Authors: CHEN YAN QIU , BI GUOAN
Published: April 2003

The fractal dimension has been studied as a feature for texture analysis. It has been found that the fractal dimension is not an effective image texture measure but little is known about the reasons for the fractal dimension failing to be effective for texture analysis. This paper investigates into the underlying causes why the fractal dimension is not an effective image texture feature. Four mathematical properties have been identified which are responsible for the fractal dimension's ineffectiveness. The experimental results show that while the fractal dimension itself is hardly an effective feature for texture classification, it can considerably enhance other feature sets.
GENETIC ALGORITHMS FOR POLYGONAL APPROXIMATION OF DIGITAL CURVES
Authors: YIN PENG-YENG
Published: April 2003

In this paper, three polygonal approximation approaches using genetic algorithms are proposed. The first approach approximates the digital curve by minimizing the number of sides of the polygon and the approximation error should be less than a prespecified tolerance value. The second approach minimizes the approximation error by searching for a polygon with a given number of sides. The third approach, which is more practical, determines the approximating polygon automatically without any given condition. Moreover, a learning strategy for each of the proposed genetic algorithm is presented to improve the results. The experimental results show that the proposed approaches have better performances than those of existing methods.
SIMULTANEOUS EDGE FLIPPING IN TRIANGULATIONS
Authors: GALTIER JERÔME , HURTADO FERRAN , NOY MARC , PÉRENNES STÉPHANE , URRUTIA JORGE
Published: April 2003

We generalize the operation of flipping an edge in a triangulation to that of flipping several edges simultaneously. Our main result is an optimal upper bound on the number of simultaneous flips that are needed to transform a triangulation into another. Our results hold for triangulations of point sets and for polygons.
Instrumented Indentation Characterization of Laser‐Induced Fe3O4/Al Composite Coating
Authors: Nayak S. , Dahotre N.B.
Published: April 2003

Instrumental indentation technoques (IIT) are useful tools not only to quantify properties such as hardness and elastic modulus, but also to provide qualitative comparison of materials behavior such as deformation, toughness, work hardening capacity, and plastic‐elastic responses in composite coatings. The authors exemplify the application of IIT on a laser‐induced Fe3O4–Al composite. The Figure shows an SEM image of a nano‐indentation impression.
“What's on the worker's mind”: Class passing and the study of the industrial workplace in the 1920s
Authors: Pittenger Mark
Published: April 2003

Posing, living, and laboring as American workers, several 1920s reformist labor investigators sought to develop an alternative to Frederick Taylor's famous characterization of a typical manual laborer as mentally akin to an ox. Through their experiences as workers, they believed that they gained real if limited access to working‐class pyschology. Accordingly, they presented views of the worker's mind that significantly loosened the strictures of hereditarian and, expecially in the case of foreign‐born workers, scientific racist thought. But their efforts were shaped by their own backgrounds and biases, and by those of the academic authorities upon whose work they built, and were also mediated through the complexities of their efforts to pass across the class line. Their work finally lent itself less to the purposes of industrial democracy and reform than to those of the rising 1920s schools of industrial psychology, industrial sociology, and personnel relations. © 2003 Wiley Periodicals, Inc.
Contrast‐enhanced peripheral MR angiography at 3.0 Tesla: Initial experience with a whole‐body scanner in healthy volunteers
Authors: Leiner Tim , de Vries Marianne , Hoogeveen Romhild , Vasbinder G. Boudewijn C. , Lemaire Etienne , van Engelshoven Jos M.A.
Published: April 2003

Purpose

To report preliminary experience with contrast‐enhanced magnetic resonance angiography (CE‐MRA) of the peripheral arteries on a 3.0 T whole‐body scanner equipped with a prototype body coil.

Materials and Methods

Four healthy volunteers were imaged on the 3.0 T system and, for comparative purposes, two of the subjects were also imaged on a commercially available 1.5 T whole‐body system. To investigate field strength influence on objective image quality, signal‐to‐noise (SN) and contrast‐to‐noise (CN) ratios were calculated for named vessels from the infrarenal aorta to the ankles at both field strengths. Comparable imaging protocols were used at both field strengths. In addition, two reviewers, blinded for field strength, gave subjective image quality scores (three‐point scale).

Results

SN and CN ratios were approximately equal on both systems (variation ≤9%) for the iliac and proximal upper leg stations. For the popliteal and lower leg stations SN ratios were 36% and 97% higher, and CN ratios were 44% and 127% higher, at 3.0 T. Subjective image quality at 3.0 T was substantially better for the distal upper and lower legs.

Conclusion

Contrast‐enhanced peripheral MRA is possible at 3.0 T when an imaging protocol similar to a current state‐of‐the‐art 1.5 T protocol is used. Objective and subjective image quality at 3.0 T is comparable for the iliac and upper legs but better for the popliteal and lower leg arteries. J. Magn. Reson. Imaging 2003;17:609–614. © 2003 Wiley‐Liss, Inc.
Ion release in the C horizon of a forest soil triggered by Carbonic Acid
Authors: Kohler Martin , Hildebrand Ernst E.
Published: April 2003

Ion release in the C horizon of a Skeletic Umbrisol on gneiss bedrock was investigated by percolation experiments at a water status near field capacity and with adjusted CO2 partial pressures in soil air. CO2 partial pressures of 0.001, 0.01, and 0.1 bar with pH‐values of 5.7, 4.9, and 4.5 yielded cation release rates of 3.0, 8.5, and 12.3 kmolc yr–1 ha–1 at a 1 m horizon depth and 800 mm seepage water. Within the pH range of 5.7 to 4.5, the activity of carbonic acid triggers ion release. For the treatment with a CO2 partial pressure of 0.001, the isolation of a weathering rate (0.5 kmolc yr–1 ha–1) was possible because parallel running processes such as the dissolution of solid compounds could be identified by dissolved anions, and exchange processes only modified internal ratios of mobilized basic cations. The weathering rate at a site‐typical CO2 partial pressure of 0.01 bar was about 5–10 times higher than usually assumed in the literature. There are three reasons that may account for this: (1) the consideration of actual carbonic acid activities and (2) specific site features such as the richness of basic minerals and/or the presence of a skeletal fraction with micro voids and fissures providing large internal surfaces. Furthermore, (3) it can not be completely excluded that parallel running exchange processes contribute to ion release.
Hair lead and cadmium concentrations in patients with epilepsy and migraine
Authors: Sasmaz Sezai , Uz Efkan , Pinar Tevfik , Vural Hüseyin , Eiri Mücahit , Ilihan Atilla , Akyol Ömer
Published: April 2003

Epilepsy and migraine are neurological manifestations of neurocutaneous diseases. The studies that investigate the etiology of these manifestations may illuminate the physiopathological bases of neurocutaneous disorders. The hypothesis that the elevation of toxic trace element concentration in the brain is an important triggering factor for seizures and subsequent neuronal damage in epilepsy and migraine was investigated in this clinical prospective study.

The levels of two heavy metals (lead [Pb] and cadmium [Cd]) in scalp hair were measured in patients with epilepsy (n=33) and migraine (n=40) as well as healthy control subjects (n=26). The hair concentration of these two toxic trace elements was determined by atomic absorption spectrophotometry. There was a significant increase in Pb concentration in epilepsy group when compared to both control (p<0.006) and migraine group (p<0.02). There was no difference in mean Cd concentration of hair from epilepsy, migraine patients and control groups. Therefore, no conclusive findings were obtained for CD. Elevated Pb content in epileptic patients was accepted as being of particular importance. Our findings support the hypothesis that the elevation in Pb concentration in the scalp hair amongst patients with epilepsy may show the elevation in the brain and constitute an important triggering factor for seizures.
Bipolaron stability in an ellipsoidal potential well
Authors: Pokatilov E. P. , Croitoru M. D. , Fomin V. M. , Devreese J. T.
Published: April 2003

Bipolaron states in ellipsoidal quantum dots are examined within the framework of Feynman's path‐integral formalism. The following characteristics of these quasiparticles are calculated: the binding energy, the number of phonons in the bipolaron cloud and the radii. The impact of both shape and size of a mesoscopic structure on the bipolaron characteristics is studied. It is shown, that in the case of strong confinement the influence of the confinement geometry is very pronounced. Two different cases are possible. (i) When the radius Rk corresponding to a given k‐axis of the ellipsoidal potential well is fixed to be less than the radius R0, at which the bipolaron binding energy in a spherical quantum dot achieves its maximum, the bipolaron binding energy passes consecutively through a local maximum and a local minimum with increasing the confinement strength corresponding to the other axes (i ≠ k). (ii) When Rk ≫ R0, the bipolaron binding energy shows only a monotonous growth with decreasing the effective sizes of the structure along the other axes (i ≠ k).
Neural networks for effect prediction in environmental and health issues using large datasets
Authors: Kaiser Klaus L. E.
Published: April 2003

Neural network methodologies allow the modeling of non‐linear relationships. This makes them useful tools for the analysis of larger data sets of non‐congeneric compounds with unknown or varying modes of action. This brief review describes recent advances and their applications to sets of several hundred to over 1 000 compounds, modeling acute toxicity data for several aquatic species, including fish, ciliate, bacteria, and non‐acute toxicity data for a mammalian species endpoint, i.e. estrogen receptor binding assay data.
Evaluation of a Novel Short‐Term Algal Toxicity Assay by the Development of QSARs and Inter‐Species Relationships for Narcotic Chemicals
Authors: Worgan Andrew D. P. , Dearden John C. , Edwards Robert , Netzeva Tatiana I. , Cronin Mark T. D.
Published: April 2003

A novel short term toxicity assay utilising the unicellular green alga Chlorella vulgaris is described. The test is based upon the premise that all living organisms contain non‐specific esterase enzymes, the activity of which can be assessed by the measurement of the disappearance of the ester, or appearance of the product. The novel assay described utilises fluorescein diacetate which is metabolised to fluorescein. The appearance of fluorescein, after 15 minutes exposure to the toxicant, was measured fluorimetrically. The concentration causing a 50% decrease in fluorescence, as compared to a control, was determined for 10 non‐polar and 10 polar narcotics. Toxicity was related significantly to hydrophobicity for both mechanisms of action, with the QSAR for polar narcosis having a lower slope and higher intercept than that for non‐polar narcosis. Significant inter‐species relationships of the toxicity data with those for a 6 hour Chlorella vulgaris, and 40 hour Tetrahymena pyriformis, toxicity assay were also observed.
Bayesian evaluation of breast cancer screening using data from two studies
Authors: Myles Jonathan P. , Nixon Richard M. , Duffy Stephen W. , Tabar Laszlo , Boggis Caroline , Evans Gareth , Shenton Andrew , Howell Anthony
Published: April 2003

The mean sojourn time (the duration of the period during which a cancer is symptom free but potentially detectable by screening) and the screening sensitivity (the probability that a screen applied to a cancer in the preclinical screen detectable period will result in a positive diagnosis) are two important features of a cancer screening programme. Little data from any single study are available on the potential effectiveness of mammographic screening for breast cancer in women with a family history of the disease, despite this being an important public health issue. We develop a method of estimation, from two separate studies, of the two parameters, assuming that transition from no disease to preclinical screen detectable disease, and from preclinical disease to clinical disease, are Poisson processes. Estimation is performed by a Markov chain Monte Carlo algorithm. The method is applied to the synthesis of two studies of mammographic screening in women with a family history of breast cancer, one in Manchester and one in Kopparberg, Sweden. Copyright © 2003 John Wiley & Sons, Ltd.
Comparing the importance of disease rate versus practice style variations in explaining differences in small area hospitalization rates for two respiratory conditions
Authors: Peköz Erol A. , Shwartz Michael , Iezzoni Lisa I. , Ash Arlene S. , Posner Michael A. , Restuccia Joseph D.
Published: April 2003

Many studies have reported large variations in age‐ and sex‐adjusted rates of hospitalizations across small geographic areas. These variations have often been attributed to differences in medical practice style which are not reflected in differences in health care outcomes. There is, however, another potentially important source of variation that has not been examined much in the literature: geographic differences in the age–sex adjusted size of the pool of patients who present with the disease and are candidates for hospitalization. Previous studies of small area variations in hospitalization rates have only used data on hospitalizations. Thus, it has not been possible to distinguish the extent to which differences in hospitalization rates are due to (i) differences in the chance that patients diagnosed with a disease are admitted to a hospital, which we refer to as the ‘practice style effect,’ versus (ii) geographic differences in the total amount of diagnosed disease, which we refer to as the ‘disease effect.’ Elementary methods for estimating the relative strength of the two effects directly from the data can be misleading, since equal amounts of variability in each effect result in unequal impacts on hospitalization rates. In this paper we describe a model‐based approach for estimating the relative importance of the practice style effect and the disease effect in explaining variations in hospitalization rates. The key to our approach is the use of data on both inpatient and outpatient visits. We use 1997 Medicare data for two respiratory medical conditions across 71 small areas in Massachusetts: chronic bronchitis and emphysema, and bacterial pneumonia. Based on a Poisson model for the process generating hospitalizations and outpatient visits, we use a Bayesian framework and Gibbs sampling to compute and compare the correlation between the number of people hospitalized and each of these two sources of variation. Our results show that for the two conditions, disease rate variation explains at least as much of the variation in hospitalization rates as does practice style variation. Copyright © 2003 John Wiley & Sons, Ltd.
Markov modelling of changes in HIV‐specific cytotoxic T‐lymphocyte responses with time in untreated HIV‐1 infected patients
Authors: Kousignian I. , Autran B. , Chouquet C. , Calvez V. , Gomard E. , Katlama C. , Rivière Y. , Costagliola D.
Published: April 2003

HIV‐specific cytotoxic CD8+ T‐lymphocytes (CTL) appear to be the cornerstone of the immune response to HIV infection. Recent studies show that CTL activity reflects patients' anti‐HIV immune status and slows disease progression. However, the dynamics of the diversity of this response also appears as a key parameter for immune control but the dynamics of this diversity is largely undocumented. We modelled changes in CTL responses against the seven principal HIV proteins over time. We also studied the influence of plasma viral load on temporal changes in HIV protein recognition by memory CTL. The generic model we developed is based on a continuous time homogeneous Markov process with reversible states. Those states are defined by the number of proteins recognized by memory CTL in a given patient at a given time. This approach was developed within a Bayesian framework. Full Bayesian inference is implemented using Markov chain Monte Carlo simulations (MCMC). The Gibbs sampling algorithm was used to estimate the marginal posterior distributions of the transition intensities between stages of CTL responses. We applied our model to data of 152 HIV‐infected patients included in the IMMUNOCO cohort. The model suggested that the diversity of HIV protein recognition by memory CTL in treatment‐naive patients decreases as the disease progresses. Namely, the loss of T cytotoxic responses is globally faster than their acquisition. Indeed, these patients' T cytotoxic responses were characterized by marked individual turnover and a gradual loss of multiple protein recognition over time, this loss accelerating as viral load increased. Copyright © 2003 John Wiley & Sons, Ltd.
Updated precipitation series for the U.K. and discussion of recent extremes
Authors: Alexander L. V. , Jones P. D.
Published: April 2003

We present an automated method for updating existing long‐running precipitation series in near‐real time. Our analyses confirm the trend towards significantly drier summers in the south‐east of England and significantly wetter winters in the west of Scotland. In 2000 England and Wales saw the wettest April since records began in 1766 and record‐breaking daily precipitation in several regions in October led to the wettest autumn on record. Copyright © 2001 Royal Meteorological Society.
A standard test for AGCMs including their physical parametrizations. II: results for the Met Office Model
Authors: Neale R. B. , Hoskins B. J.
Published: April 2003

Example results are shown for the proposed aqua‐planet experiments using a version of The Met Office Unified Model (UM). The zonal mean circulation exhibits strong sensitivity to the latitudinal distribution of sea‐surface temperatures (SST). Longitudinal variation of SST yields information on the linearity and distribution of the convective response. Copyright © 2001 Royal Meteorological Society.
Recent historical land use change on the South Downs, United Kingdom
Authors: Burnside Niall G. , Smith Roger F. , Waite Stephen
Published: April 2003

There is considerable interest in the fragmentation and loss of natural and semi-natural habitats, but few studies have examined the dynamics and mechanisms of change. A temporal analysis of landscape change on the South Downs in Sussex, UK, provides a clear description of the process of change over the 20 years 1971–1991. Transition probabilities were calculated from digital interpretations of an aerial photography time series of West Sussex. The analysis enabled quantitative comparison of landscape mosaics within different landscape ecoregions and under different management regimes to be made. Past changes in land use have produced a fragmented downland landscape. The key land conversion sequences identified show a substantial transition towards arable production, often at the expense of the internationally and nationally important unimproved grassland systems. A geographical information system facilitated greater understanding of the environmental and topographical characteristics of land converted to arable and other uses, and highlighted areas for protection and potential restoration. The patterns of land-use conversion observed in the study provide a landscape-scale planning tool for assessing the potential impact of agri-environmental policies, plans, and programmes in semi-natural grassland habitats.
Traditional agroecological knowledge, adaptive management and the socio-politics of conservation in Central Sulawesi, Indonesia
Authors: Armitage Derek R.
Published: April 2003

This paper illustrates the opportunity for conservation offered by linking traditional agroecological knowledge and advances in adaptive management theory and practice. Drawing on examples from the Banawa-Marawola region of Central Sulawesi, Indonesia, a suite of traditional resource management practices premised on principles of adaptive management are identified and assessed, including: (1) resource management practices and regulations that are associated with the dynamics of complex systems;
(2) procedural, planning and decision-making processes that foster learning; (3) sanctions and taboos that act as social mechanisms for the management and conservation of natural resources; and (4) ceremonies and social interactions that promote cultural internalization of the various practices, procedures and mechanisms. In addition, an emerging socio-political movement in the Banawa-Marawola region is explored. Premised on the strengthening of traditional rights and practices, the nascent Kamalise movement potentially provides the socio-political, institutional and organizational context needed to link traditional agroecological knowledge and adaptive management with broader conservation goals. Based on this analysis, two opportunities to enhance conservation in the region are identified: first, maintaining traditional agroecological systems and the associated adaptive resource management strategies used by local groups, and second, building upon the Kamalise movement to forge conservation alliances among communities, non-government and government organizations in which locally-evolved adaptive resource management strategies can be effectively applied. Both opportunities to combine traditional knowledge, adaptive management and conservation, however, are linked to the development aspirations of traditional groups: self-determination, acquisition of land rights and controlling the impacts of changes in livelihood.
Flexible working patterns using annualised hours
Authors: Rodriguez M.
Published: April 2003

An increasing number of UK companies is adopting the practice of establishing employee working patterns under a system of annualised hours to offer greater flexibility. This paper describes the concept, examines the advantages of adopting such a system and gives a broad framework to support its effective introduction.
GRAY IMAGE SKELETONIZATION WITH HOLLOW PREPROCESSING USING DISTANCE TRANSFORMATION
Authors: QIAN KAI , CAO SIQI , BHATTACHARYA PRABIR
Published: April 2003

This paper presents a gray-scale skeletonization algorithm based on the gray weighted distance transformation (GWDT). The proposed algorithm is conceptually simple and could be used to process nonuniformly distributed gray-scale images. The algorithm can detect the hollows on the gray-scale image, a feature that is often ignored in other skeletonization algorithms, and improves the quality of the skeleton.
Activation-induced PPARγ expression sensitizes primary human T cells toward apoptosis
Authors: Tautenhahn Anja , Brüne Bernhard , von Knethen Andreas
Published: April 2003

Phytohemagglutinin (PHA) elicited expression of peroxisome proliferator-activated receptor γ (PPARγ) in primary human T cells via the PPARγ3 promoter, as shown by reverse transcription-polymerase chain reaction. Electrophoretic mobility shift assay demonstrated no correlation between PPARγ expression and its activation. However, addition of specific PPARγ agonists such as ciglitazone or 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) for 1 h following PHA pretreatment provoked PPARγ activation verified by supershift analysis. Taking the proapoptotic properties of PPARγ into consideration, we analyzed induction of apoptosis in activated T cells in response to PPARγ agonists. Cells exposed to PPARγ agonists alone revealed minor cell death compared with controls, whereas treatment with 15d-PGJ2 or ciglitazone for 4 h subsequent to PHA stimulation significantly increased cell demise, which was attenuated by the pan-caspase inhibitor zVAD, pointing to apoptosis as the underlying mechanism. These data may be relevant for pathophysiological conditions accompanied with lymphopenia of T cells under conditions such as sepsis.
All Oxide Ceramic Multilayer Coating for High‐Temperature Thermal Energy Window
Authors: Matsumura K. , Naganuma T. , Kagawa Y.
Published: April 2003

An intelligent coating as an energy window with great potential for high‐temperature energy saving applications is presented. The coating is a multilayer ZrO2/Al2O3 ceramic fabricated by spin‐coating onto an alumina substrate (see Figure for a cross‐section). By selecting an optimal thickness and number of ZrO2 and Al2O3 layers, the thermal radiation energy entering a substrate at high temperature can be controlled to select the transmission/reflection.
Der Briefwechsel Jean‐Daniel Buchingers (Bestandsübersicht). Ein deutsch‐französischer Beitrag zur Geschichte der Naturwissenschaften im 19. Jahrhundert
Authors: Robin Nicolas
Published: April 2003

Jean‐Daniel Buchinger (1803‐1888) est de ces hommes qui ont œuvré toute leur vie au service de la science et de la communauté scientifique, sans pour autant que leurs noms passent à la postérité. Inspecteur des écoles primaires du Bas‐Rhin puis directeur de l'orphelinat de Strasbourg, il est surtout connu par la communauté scientifique comme botaniste. J.‐D. Buchinger est au centre d'un réseau franco‐allemand d'échanges d'herbiers et d'ouvrages de sciences naturelles. La correspondance de cet érudit strasbourgeois du 19ème siècle témoigne de son rôle d'intermédiaire scientifique. La Bibliothèque Nationale et Universitaire de Strasbourg conserve plus de 15000 lettres adressées à J.‐D. Buchinger ou composant sa collection personnelle d'autographes. Il était nécessaire de créer une nouvelle entrée à cette source de manuscrits dont l'inventaire ci‐joint constitue une base de recherche pour l'historien.
Explaining adult homelessness in the US by stratification or situation
Authors: Sosin Michael R.
Published: April 2003

In the US, the most widely accepted individual‐level explanations of homelessness suggest that adults lose their dwellings when they cannot compete in the marketplace for the monetary resources needed to pay for housing, and cannot compete in a non‐market struggle for compensatory resources. Such resource problems allegedly typically reflect myriad lifetime and current personal problems or deficits. However, the causal role of the problems and deficits is now known to be complex, and evidence about transitions in and out of homelessness suggests that key events occur somewhat independently of easily measured individual problems or deficits. This article, therefore, provides an alternative explanatory approach that directly focuses on aspects of the probabilistic situations that spur, or fail to reverse homelessness. The events and resource issues are posited to give rise to episodes of homelessness that vary in length, that are indirectly affected by many commonly mentioned individual traits, and that can be matched to targeted policies. Copyright © 2003 John Wiley & Sons, Ltd.
Percutaneous atrial septostomy for urgent palliative treatment of severe refractory cardiogenic shock due to right ventricular infarction
Authors: Kernis Steven J. , Goldstein James , Yerkey Michael , Levin Robert N. , O'Neill William W.
Published: April 2003

We report a novel palliative treatment to improve refractory cardiogenic shock due to right ventricular ischemia. We performed percutaneous atrial septostomy to create an atrial septal defect, which resulted in immediate right ventricular decompression and increased left ventricular filling associated with prompt and dramatic hemodynamic and clinical improvement. Cathet Cardiovasc Intervent 2003;59:44–48. © 2003 Wiley‐Liss, Inc.
Diastereoselective Zinc‐Mediated Barbier‐Type Allylation and Propargylation of 3‐Formylcephalosporins
Authors: Keltjens Rolf , Vadivel Subramanian K. , Gelder René de , Klunder Antonius J. H. , Zwanenburg Binne
Published: April 2003

We describe the allylation and propargylation of 3‐formylcephalosporins under zinc‐mediated, aqueous Barbier conditions, from which the corresponding homoallylic alcohols are produced in good yields and with good‐to‐excellent diastereoselectivity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Efficient Intramolecular Hydroamination of Unactivated Alkenes Catalysed by Butyllithium
Authors: Ates Ali , Quinet Coralie
Published: April 2003

In this communication, we wish to report some preliminary results demonstrating, for the first time, that intramolecular hydroamination of unactivated alkenes can be performed efficiently using small quantities of nBuLi as the pre‐catalyst. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003
Cover Picture: 2,7,12,17‐Tetra(p‐butylphenyl)‐3,6,13,16‐tetraazaporphycene: The First Example of a Straightforward Synthetic Approach to a New Class of Photosensitizing Macrocycles (Eur. J. Org. Chem. 9/2003)
Authors: Nonell Santi , Borrell José I. , Borrós Salvador , Colominas Carles , Rey Oscar , Rubio Noemí , Sánchez‐García David , Teixidó Jordi
Published: April 2003

The cover picture shows a three‐dimensional model of 2,7,12,17‐tetra(p‐butylphenyl)‐3,6,13,16‐tetraazaporphycene, the first example of a new class of sensitizing porphyrinoid macrocycles. Starting from glyoxal and ammonia, the synthetic methodology includes Suzuki and McMurry couplings, using the depicted tetrabromobiimidazole as the key intermediate. The macrocycle has excellent light absorption properties in the red and near‐infrared regions (600−800 nm), an attractive feature for biomedical applications such as photodynamic therapy. Details are discussed in the article by J. Teixidó et al. on p. 1635 ff.
Volume‐selective 3D turbo spin echo imaging for vascular wall imaging and distensibility measurement
Authors: Crowe Lindsey A. , Gatehouse Peter , Yang Guang Zhong , Mohiaddin Raad H. , Varghese Anitha , Charrier Clare , Keegan Jennifer , Firmin David N.
Published: April 2003

Purpose

To use a volume‐selective 3D turbo spin echo (TSE) technique to image the carotid artery wall and measure distensibility.

Materials and Methods

A high‐resolution volume‐selective 3D TSE sequence has been developed. Volume selection is accomplished by orthogonal gradients for the 90° and 180° excitations and allows a 3D volume of vessel wall to be imaged in a relatively short time. The technique has been developed to allow imaging at any defined phase of the cardiac cycle so that the vascular function and distensibility can be studied.

Results

Scan efficiency is increased by the reduced phase encode field of view (FOV) (ky steps) by the use of selective volume excitation. Significantly more slices (kz phase encode steps) for vessel coverage can be acquired with the same scan time as that of the conventional sequence while maintaining signal‐to‐noise ratio (SNR) levels. The practical value of the technique was demonstrated on 10 normal subjects with high‐resolution vessel distensibility measurements of the carotid arteries.

Conclusion

A volume‐selective TSE method has been used for carotid artery wall imaging and measurement of distensibility in normal subjects. Larger coverage of the vessel, and therefore more information for clinical diagnostics, was achieved with the same overall scan time with an SNR comparable to that of 2D full FOV images. J. Magn. Reson. Imaging 2003;17:572–580. © 2003 Wiley‐Liss, Inc.