bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient formulation of a bivariate nonic
C
2
-hermite polynomial on triangles
Authors: Preusser Albrecht
Published: July 2002

Bivariate polynomials over triangular domains are widely in use for the definition of surfaces that are continuously differentiable across a set of triangles. A description is given of how explicit formulas for the coefficients of bivariate nonic polynomials can be found with the help of a computer algebra system. A linear system with 55 equations and 45 nonzero right hand sides must be solved algebraically. The interpolant is twice differentiable across triangle sides and based on function values and partial derivatives up to fourth order at the nodes. Horner's scheme for evaluating polynomials can be applied directly, leading to optimal efficiency during the evaluation phase (54 additions and multiplications for one point). Starting with transformed nodal data, the calculation of one set of coefficients takes about 350 additions, the same number of multiplications, and 30 divisions.—
Author's Abstract
A dynamic hierarchical subdivision algorithm for computing Delaunay triangulations and other closest-point problems
Authors: Palacios-Velez Oscar
Published: July 2002

A new, dynamic, hierarchical subdivision and recursive algorithm for computing Delaunay triangulations is presented. The algorithm has four main steps: (1) location of the already formed triangle that contains the point (2) identification of other adjoining triangles whose circumcircle contains the point (3) formation of the new triangles, and (4) database update. Different search procedures are analyzed. It is shown that the “oriented walk” search, when the total number of points is less than 417 or when the points are presorted by distance or coordinates. The algorithm has point-deletion capabilities which are discussed in detail.
Trellis: turning designs into programs
Authors: Kilian Michael
Published: July 2002

When designing an object-oriented program, there are several goals to achieve:

The Trellis programming system is an integrated language and environment that provides many of the mechanisms needed to design and implement object-oriented programs. The remainder of this sidebar discusses how Trellis helps attain the goals outlined above.
Data caching issues in an information retrieval system
Authors: Alonso Rafael , Barbara Daniel , Garcia-Molina Hector
Published: July 2002

Currently, a variety of information retrieval systems are available to potential users.… While in many cases these systems are accessed from personal computers, typically no advantage is taken of the computing resources of those machines (such as local processing and storage). In this paper we explore the possibility of using the user's local storage capabilities to cache data at the user's site. This would improve the response time of user queries albeit at the cost of incurring the overhead required in maintaining multiple copies. In order to reduce this overhead it may be appropriate to allow copies to diverge in a controlled fashion.… Thus, we introduce the notion of
quasi-copies
, which embodies the ideas sketched above. We also define the types of deviations that seem useful, and discuss the available implementation strategies.—From the Authors' Abstract
Scaling up output capacity and performance results from information systems prototypes
Authors: Westland J. C.
Published: July 2002

The advantage of information system prototyping arises from its predict problems and end-user satisfaction with a system early in the development process, before significant commitments of time and effort have been made. Predictions of problems and end-user satisfaction have risen in importance with the increasing complexity of business information systems and the exponential growth of database size. This research investigates the reporting of information to an end user, and the process of inferring from a prototype to a full-scale information system. This inference is called
scaling up
, and is an important part of the systems development planning process. The research investigates information systems reporting from a linguistic perspective, where a database is used as a central receptacle for information storage. It then investigates the manner in which reporting statistics from the prototype information system may be used to infer the behavior and performance of the full-scale system. An example is presented for the application of the algorithm, and the final section discusses the usefulness, application, and implications of the algorithm developed in this research.
REGIONAL PHOTOCHEMICAL AIR QUALITY MODELING:Model Formulations, History, and State of the Science
Authors: Russell Armistead
Published: July 2002

▪ Abstract  Regional air quality models have been used for scientific investigation of trace species dynamics for over two decades and are now beginning to take a central position in air quality management. In particular, they have been used for studying the transport and fate of atmospheric acids, photochemical oxidants (e.g. ozone), and more recently, aerosols. Such models are based on numerically solving the mass conservation equations for a chemically interacting system of species and are applied to horizontal domains of 1000s of kms. Primary applications include assessing the response of pollutant concentrations to emissions controls, quantifying the flux of pollutants across and out of a region, and understanding the impact of specific processes on pollutant concentrations.
THE O2 BALANCE OF THE ATMOSPHERE: A Tool for Studying the Fate of Fossil-Fuel CO2
Authors: Bender Michael L. , Battle Mark , Keeling Ralph F.
Published: July 2002

▪ Abstract  Carbon dioxide is a radiatively active gas whose atmospheric concentration increase is likely to affect Earth's climate. CO2 is added to the atmosphere by biomass burning and the combustion of fossil fuels. Some added CO2 remains in the atmosphere. However, substantial amounts are taken up by the oceans and land biosphere, attenuating the atmospheric increase. Atmospheric O2 measurements provide one constraint for partitioning uptake rates between the ocean and the land biosphere. Here we review studies of atmospheric O2 concentration variations and discuss their implications for CO2 uptake by the ocean and the land biosphere. We compare estimates of anthropogenic carbon fluxes from O2 studies with estimates from other approaches and examine the contribution of natural ocean carbon fluxes to atmospheric O2 variations.
Congenital Disorders of Glycosylation
Authors: Jaeken Jaak , Matthijs Gert
Published: July 2002

Congenital disorders of glycosylation (CDG) are a rapidly growing group of genetic diseases that are due to defects in the synthesis of glycans and in the attachment of glycans to other compounds. Most CDG are multisystem diseases that include severe brain involvement. The CDG causing sialic acid deficiency of N-glycans can be diagnosed by isoelectrofocusing of serum sialotransferrins. An efficient treatment, namely oral D-mannose, is available for only one CDG (CDG-Ib). In many patients with CDG, the basic defect is unknown (CDG-x). Glycan structural analysis, yeast genetics, and knockout animal models are essential tools in the elucidation of novel CDG. Eleven primary genetic glycosylation diseases have been discovered and their basic defects identified: six in the N-glycan assembly, three in the N-glycan processing, and two in the O-glycan (glycosaminoglycan) assembly. This review summarizes their clinical, biochemical, and genetic characteristics and speculates on further developments in this field.
Cyclosporine Treatment of Glomerular Diseases
Authors: Klein Michael , Radhakrishnan Jai , Appel Gerald
Published: July 2002

Cyclosporine-A is primary therapy for organ transplantation. Its immunosuppressive effect might suggest a therapeutic role in autoimmune diseases, including several idiopathic and secondary glomerular conditions. Various forms of idiopathic nephrotic syndrome, including focal segmental glomerulosclerosis (FSGS), minimal change disease (MCD), and membranous nephropathy (MN), may respond well to cyclosporine in selected patients. However, frequent relapse limits its use to those who have failed to respond to, or were intolerant of, steroids or cytotoxics. Cyclosporine's efficacy in other glomerulopathies, such as IgA nephropathy (IgAN) and membranoproliferative glomerulonephritis (MPGN) remains poorly studied and, given the risk of nephrotoxicity, cannot be recommended for treatment of these entities until further data are available. Cyclosporine demonstrates some efficacy in treating proliferative lupus nephritis and, based on pilot study data, membranous lupus as well. Again, given relapse rates and potential nephrotoxicity, it should be used only in combination with azathioprine and steroids, assuming cytotoxic therapy has failed. Finally, cyclosporine toxicity is briefly reviewed.
Immunologic Control of HIV-1
Authors: Gandhi Rajesh T. , Walker Bruce D.
Published: July 2002

▪ Abstract  By destroying CD4+ T cells, human immunodeficiency virus-1 (HIV-1) infection results in immunodeficiency and the inability of the immune system to contain the virus in most individuals. Although treatment of HIV-1 infection with potent antiretroviral medications has resulted in enormous clinical benefit, there is a growing recognition of the limitations of this therapy. As a result, novel approaches to treating HIV-1 infection are being considered. One such strategy is immunotherapy, which seeks to boost immune responses against HIV-1 and control the virus. This approach is based on studies of other viruses in which a coordinated immune response contains the chronic infection. Recent studies show that CD4+ helper responses, CD8+ T cell activity, and antibodies may contribute to control of the virus without antiretroviral therapy in some HIV-positive individuals. Based on this understanding of the immunologic correlates of control of HIV-1, exciting new immunotherapeutic strategies for HIV-1 infection are being designed and tested.
IMMUNOPATHOGENESIS OF HIV INFECTION
Authors: Pantaleo G. , Fauci A. S.
Published: July 2002

The rate of progression of HIV disease may be substantially different among HIV-infected individuals. Following infection of the host with any virus, the delicate balance between virus replication and the immune response to the virus determines both the outcome of the infection, i.e. the persistence versus elimination of the virus, and the different rates of progression.

During primary HIV infection, a burst of viremia occurs that disseminates virus to the lymphoid organs. A potent immune response ensues that substantially, but usually not completely, curtails virus replication. This inability of the immune system to completely eliminate the virus leads to establishment of chronic, persistent infection that over time leads to profound immunosuppression. The potential mechanisms of virus escape from an otherwise effective immune response have been investigated. Clonal deletion of HIV-specific cytotoxic T-cell clones and sequestration of virus-specific cytotoxic cells away from the major site of virus replication represent important mechanisms of virus escape from the immune response that favor persistence of HIV. Qualitative differences in the primary immune response to HIV (i.e. mobilization of a restricted versus broader T-cell receptor repertoire) are associated with different rates of disease progression. Therefore, the initial interaction between the virus and immune system of the host is critical for the subsequent clinical outcome.
MICROPATTERNGASEOUSDETECTORS
Authors: Sauli Fabio , Sharma Archana
Published: July 2002

▪ Abstract  Introduced in 1988, microstrip gas chambers perform considerably better than classic multiwire detectors. Excellent localization, high rate capability, and good granularity make them attractive for charged-particle tracking at high-luminosity colliders, among other applications. The technology continues to improve; for example, substrates have been developed that prevent charge accumulations. Some problems persist, namely the slow degradation under sustained irradiation (aging) and the serious damage that can result from accidental discharges. New types of detectors aim at improving on these points; the microdot, micromegas, and gas electron multiplier detectors are promising examples. They are generally more reliable and cheaper.
My Only Sunshine: Installation Art Experiments with Light, Space, Sound and Motion
Authors: Steinkamp Jennifer
Published: July 2002

The author discusses her interactive architectural installation art. As an artist who works with new media, she finds herself refitting existing genres and creating new languages for her particular art form. Her artwork consists of projected interactive computer animation installations. She investigates illusions that transform the viewer's perception of actual space in a synthesis of the real and the virtual.
The Old Testament Trinity of Andrey Rublyov: Geometry and Philosophy
Authors: Voloshinov Alexander V.
Published: July 2002

The philosophical and theological content of a masterpiece of Old Russian icon-painting—Andrey Rublyov's Trinity is regarded in the light of its geometry. The aspects under study are the geometrical properties of the rectangle of the Trinity (which generate a sequence of circumferences related by the golden proportion) and also some of the peculiarities in the composition of the icon. The roles of the circle, the octagon and inverse perspective in the Trinity are discussed. The author establishes correspondence between the theological triad Revelation—Illumination Transformation, which makes up the fundamental content of the Trinity, and the mirror and dynamic symmetries of the icon.
The Early Restart Algorithm
Authors: Magdon-Ismail Malik , Atiya Amir F.
Published: July 2002

Consider an algorithm whose time to convergence is unknown (because of some random element in the algorithm, such as a random initial weight choice for neural network training). Consider the following strategy. Run the algorithm for a specific time T. If it has not converged by time T, cut the run short and rerun it from the start (repeat the same strategy for every run). This so-called restart mechanism has been proposed by Fahlman (1988) in the context of backpropagation training. It is advantageous in problems that are prone to local minima or when there is a large variability in convergence time from run to run, and may lead to a speed-up in such cases. In this article, we analyze theoretically the restart mechanism, and obtain conditions on the probability density of the convergence time for which restart will improve the expected convergence time. We also derive the optimal restart time. We apply the derived formulas to several cases, including steepest-descent algorithms.
RST: A Connectionist Architecture to Deal with Spatiotemporal Relationships
Authors: Chappelier J.-C. , Grumbach A.
Published: July 2002

In the past decade, connectionism has proved its efficiency in the field of static pattern recognition. The next challenge is to deal with spatiotemporal problems. This article presents a new connectionist architecture, RST (ŕeseau spatio temporel [spatio temporal network]), with such spatiotemporal capacities. It aims at taking into account at the architecture level both spatial relationships (e.g., as between neighboring pixels in an image) and temporal relationships (e.g., as between consecutive images in a video sequence).

Concerning the spatial aspect, the network is embedded in actual space (two-or three-dimensional), the metrics of which directly influence its structure through a connection distribution function. For the temporal aspect, we looked toward biology and used a leaky-integrator neuron model with a refractory period and postsynaptic potentials.

The propagation of activity by spatiotemporal synchronized waves enables RST to perform motion detection and localization in sequences of video images.
Validation of Voting Committees
Authors: Bax Eric
Published: July 2002

This article contains a method to bound the test errors of voting committees with members chosen from a pool of trained classifiers. There are so many prospective committees that validating them directly does not achieve useful error bounds. Because there are fewer classifiers than prospective committees, it is better to validate the classifiers individually than use linear programming to infer committee error bounds. We test the method using credit card data. Also, we extend the method to infer bounds for classifiers in general.
The Biomechanics of Aggression Psychophysiological Conditioning in Ulster's Loyalist Parades
Authors: Tuite Patrick
Published: July 2002

Annually, Ulster's Protestant loyalists parade through the streets of Ulster. These in-your-face demonstrations of power by the Orangemen have ignited violence each year, from 1995 to 2000. What physiological and psychological mechanisms preserve the loyalist parades, and incite the violence associated with them?
Litvinov's Lost Peace, 1941–1946
Authors: Roberts Geoffrey
Published: July 2002

The German invasion of the Soviet Union in 1941 and the ensuing conflict witnessed the political rehabilitation of the former People's Commissar for Foreign Affairs, Maksim Litvinov. After serving as ambassador to the United States from 1941 to 1943, Litvinov returned to the Soviet Union and played a key role in charting Moscow's wartime Grand Alliance strategy. He urged So-viet leaders to convene a joint Anglo-Soviet-American commission to discuss military-political questions, and he helped organize the October 1943 foreign ministers'conference in Moscow. As the war drew to a close, Litvinov argued for a postwar settlement dividing the world into security zones. His realist conception of foreign policy suggested a more moderate alternative o Josif Stalin's reliance on confrontation with the West. Although Litvinov faded again from public view after his retirement in 1946, his belief that the Grand Alliance could continue suggests that the rapid, postwar descent into the Cold War might have been averted had it not been for Stalin.
MANAGING MARTYRDOM: FEMALE SUICIDE AND STATECRAFT IN MID-QING CHINA
Authors: Theiss Janet
Published: July 2002

During the first 150 years of Qing rule, the suicides of women were the subject of unprecedented quantities of legal and ritual legislation and a frequent topic of debate in imperial, official, and literati discourses on law, ethics, and social order. This legislation often appeared contradictory, banning honors for suicide in principle, yet granting frequent exceptions. This article examines the complex array of political, cultural, and social factors that produced this intensification of state and elite interest in female suicide and created the apparent inconsistency of state policies. It argues that evolving Qing policies toward female suicide reflected a surprising convergence of statecraft goals, Qing imperial agendas, Han literati interest in promoting orthodox social norms, Manchu ethnic concerns, and the enduring fascination that the pathos of the female martyr held for male rulers and officials in general.
TO LOCK UP ELEUSIS: A QUESTION OF LIMINAL SPACE
Authors: Endsjø Dag Øistein
Published: July 2002

In this article, I argue that the geographical periphery, the eschatia, represented an area within the ancient Greek worldview that reflected a territorial parallel to the intermediate state of the Greek rites of passage. There were also a number of mythological ties between the eschatia and this ritual mid state, the most basic aspect of both of them consisting of a simultaneous being and non-being that entailed a sense of profound confusion of all proper categories. Placed not only betwixt and between the land of the dead and polis as the land of the living, but also between an Olympian and a chthonic divine sphere, the uncultivated geographical periphery represented an ambiguous and primordial landscape, where men had still not been distinguished from the realm of the gods, the animals, and the dead. As the geographical periphery thus was considered to reflect a primordial quality, the intermediate phase of various rites of passage was seen as the ritual imitation of this area. Having journeyed to the ends of the earth and the land of the dead, Heracles could therefore suggest closing down the Eleusian mysteries. Operating with a theoretical concept of liminal space, I will in this way try to show how the idea of ritual liminality, as initiated by Arnold van Gennep and Victor Turner, may be transferred to a spatial context.
LA BIBLIOTHÈQUE TOURNANTE EN CHINE: QUELQUES REMARQUES SUR SON RÔLE ET SON ÉVOLUTION 1
Authors: Loveday Helen
Published: July 2002

"Shi Zhifu du monastère de Changlu à Zhenzhou fit ériger dans une haute salle un grand pivot et deux roues; entre les roues il abrita les boîtiers du canon en 5048 chapitres. La somme d'argent réunie se montait à 3 millions de pièces; l'ornementation d'argile et de bois laqués, de jade et d'or, est sublime. Les paroles restent impuissantes à la louer, ce n'est que par le regard qu'il est possible de l'appréhender."2
AN ADDITIONAL NOTE TO TWO RECENT ARTICLES ON THE NUMBER OF PEOPLE IN THE EXODUS FROM EGYPT AND THE LARGE NUMBERS IN NUMBERS I AND XXVI
Authors:   Rendsburg
Published: July 2002

This short note deduces evidence in support of both E. W. Davies (with qualification) and C. J. Humphreys in their differing approaches to the problem of the large number of Israelites during the exodus and wandering.
THE BINDING OF ISAAC: AN INNER-BIBLICAL POLEMIC ON THE QUESTION OF "DISOBEYING" A MANIFESTLY ILLEGAL ORDER
Authors: Boehm Omri
Published: July 2002

It is traditionally accepted among scholars that the "original" episode of the Akedah is narrated in Gen. xxii 1-13, 19. Verses 14-18, the "second angelic speech", offering Abraham a blessing for his obedience, are usually considered, on stylistic, structural and critical grounds, a secondary interpolation. Recent studies, however, have argued that Abraham's extraordinary obedience actually necessitates the extra blessings which he receives in the second angelic speech. It, therefore, could not have been simply inserted into the original account. This has suggested to many scholars that the author responsible for vv. 15-18 has left his mark also on vv. 1-13, 19. In re-examining the style, composition and content of this story, I will suggest that the mark may be found in the first angelic speech, stopping Abraham at the crucial moment (vv. 11-12). Without the angelic intervention an episode would emerge in which Abraham disobeyed the divine command, sacrificing the ram "instead of his son", on his own responsibility.
The influence of tadpole size on cell-mediated competition between anuran larvae Bufo calamita and Rana temporaria) in the laboratory
Authors: Wong Adeline , Beebee Trevor J.C. , Griffiths Richard
Published: July 2002

The faeces of tadpoles frequently contain cells that can inhibit the growth of other individuals. We examined the mechanism of such cell-mediated interference competition in interactions between tadpoles of Rana temporaria and Bufo calamita. When R. temporaria and B. calamita tadpoles were exposed to cell-laden faeces from larger R. temporaria tadpoles, growth was inhibited relative to controls. Tadpoles of B. calamita remained susceptible to the inhibitory effects of the cells for longer during development than those of R. temporaria. In the presence of excess food, cell production by both species was related to stage of development. Tadpoles raised with cell-laden faeces from R. temporaria tadpoles produced more cells/tadpole/hour than those raised without competitor faeces, and smaller tadpoles were more inhibited than larger tadpoles.
EFFECTS OF FREQUENCY AND LENGTH OF SEPARATION BOUTS BETWEEN MOTHER AND OFFSPRING ON LATER EXPLORATIVE BEHAVIOUR OF YOUNG GUINEA-PIGS (CAVIA APEREA F.PORCELLUS)
Authors: Albers P.C.H. , Timmermans P.J.A. , Vossen J.M.H.
Published: July 2002

Previous studies have shown that maternal behaviour is correlated with later explorative behaviour of the young. Exploring the eventual effects of maternal behaviour on the explorative behaviour of young guinea pigs, we examined the effects of frequency and length of separation bouts between mother and offspring. For 39 pups daily duration of contact with the mother was kept constant (17 hours) but the frequency of daily contact (and thus the length of the separation bouts) varied. Using a split-litter design three groups were created that were separated from the mother 3, 6 or 9 times each day from day 3 until day 20. Several precautions were taken to avoid distress of the pups during separation caused by heat loss, social isolation or unfamiliarity with the separation cage. The development of the explorative behaviour was assessed by means of a series of tests representing several aspects of explorative behaviour. All groups showed equal growth during the treatment period. It is shown that the group separated 3 times for a long period scored higher in explorative behaviour than the other groups that were separated more often but for shorter periods. In particular walking, duration of presence, and sniffing in the novel environment were increased compared to the groups separated 6 or 9 times but were also increased when compared to average scores of a previous study. It could be shown that individuals were persistent in time with regard to the maximum distance they entered into a novel environment.
The effect of artificial substrates on the pathogenicity of Steinernema feltiae (Rhabditida: Steinernematidae) to adult Musca domestica (Diptera: Muscidae)
Authors: Renn Nick , Wright Elaine
Published: July 2002

Effects of some artificial substrates on the ability of the entomopathogenic
nematode Steinernema feltiae to kill adult Musca domestica were studied.
Replicate samples of different substrates were treated with known numbers of
S. feltiae suspended in 0.25 M sucrose. Then 30 adult female flies were
confined above each sample in a crystalizing basin and mortality counts were
carried out 48 h later. The most effective substrates were poplin cotton,
potting compost, silver sand and Fibertex SF250 horticultural capillary
matting, which gave LD50 in the range of 2815 to 8912 S. feltiae.
Conversely, Perlite was the least efficient material and required between
531 450 and 899 930 S. feltiae to achieve the LD50. These effects appeared
to be related to the total porosity (ratio of the volume of air spaces in
each material to its bulk volume) of each material, with the most efficient
materials having total porosities in a median range of between 0.81 and
0.14. The significance of these observations is discussed. Les effets de
certains substrats artificiels sur l’aptitude du nématode entomopathogène
Steinernema feltiae à tuer les adultes de Musca domestica ont été étudiés.
Des sérics d’échantillons de différents substrats ont été traitées avec des
nombres connus de S. feltiae en suspension dans une solution de saccharose
0,25 M. Trente mouches femelles adultes ont été ensuite enfermées au-dessus
de chaque échantillon, dans un cristallisoir, et des dénombrements de
mortalité effectués 48 h plus tard. Les substrats les plus efficaces ont été
la popeline de coton, le terreau de rempotage, le sable micacé et le
Fibertex SF250, une natte capillaire horticole, qui ont permis d’atteindre
la LD50 dans la fourchette de 2815 à 8912 S. feltiae. Par contre, la Perlite
s’est révélée le matériau le moins efficace, et il a fallu entre 531 450 et
899 930 S. feltiae pour atteindre la LD50. Ces effets semblent liés à la
porosité totale (rapport entre le volume des espaces remplis d’air dans
chaque matériau et son volume en vrac) des matériaux, celle des plus
efficaces étant située dans une fourchette médiane de 0,81 et 0,14.
L’importance de ces observations est discutée.
Resistance to rice root-knot nematode Meloidogyne graminicola identified in Oryza longistaminata and O. glaberrima
Authors: Soriano Imelda R. , Schmit Veronique , Brar Darshan S. , Prot Jean-Claude , Reversat Georges
Published: July 2002

Accessions of Oryza longistaminata and O. glaberrima, two rice species from
Africa, and O. sativa were screened to identify sources of resistance to
Meloidogyne graminicola. An initial population of 6000 J2/plant was
inoculated to cuttings of the African rice species and 5-day-old seedlings
of O. sativa. Root nematode densities were estimated 60 days after the last
inoculation. O. sativa entries were all susceptible to the rice root-knot
nematode. One accession of O. longistaminata represented by two individuals
(WL02-2 and WL02-15) and three accessions of O. glaberrima (TOG7235, TOG5674
and TOG5675) were resistant to M. graminicola. DL01-1, an O. longistaminata
accession, was susceptible to the rice root-knot nematode. Identification de
sources de resistance a Meloidogyne graminicola chez Oryza longistaminata et
O. glaberrima - Plusieurs accessions d'Oryza longistaminata et d'O.
glaberrima, deux riz africains, et d'O. sativa ont ete criblees pour trouver
des sources de resistance a Meloidogyne graminicola. Des inoculums de 6000
J2 par plante ont ete inocules sur des boutures des deux riz africains et
sur des plantules de 5 jours d'O. sativa. Les populations presentes dans les
racines ont ete evaluees 60 jours apres l'inoculation. Toutes les varietes
testees d'O. sativa etaient sensibles. Une accession d'O. longistaminata,
representee par deux individus (WLO2-2 et WLO2-15), et trois accessions d'O.
glaberrima (TOG7235, TOG5674 et TOG5675) etaient resistantes.
Magnetic anisotropy and X- ray diffraction study of clay minerals in the decollement horizons of the western Helvetic nappes, SW Switzerland
Authors: Dick P. , Burkhard M.
Published: July 2002

Anisotropy of magnetic susceptibility (AMS) and X-ray diffraction studies on shale decollement horizons in the Western Helvetic nappes were conducted to delineate the interactions between clay particles and deformation during a non-coaxial thrusting deformation. The reorientation of magnetic lineations in the decollement horizons, from a NW—SW thrusting direction to a NE—SW oriented lateral escape, provides the opportunity to study the evolution of magnetic fabrics and clay mineralogy during a two-step deformation history. The AMS of these shales originates from paramagnetic phyllosilicate minerals: illite, phengite and chlorite. Clay mineral studies indicate that magnetic lineations parallel to the thrust directions correspond to the spatial organization of the basal planes of phengites, whereas those parallel to the lateral escape movement are caused by illites. This work indicates that the change in direction of magnetic lineations from orogenic contraction to lateral escape not only records the strain history but also the dissolution and neoformation of paramagnetic minerals.
Application of phenyl salicylate-sepiolite systems as ultraviolet radiation filters
Authors: del Hoyo C. , Vicente M. A. , Rives V.
Published: July 2002

The interaction between phenyl salicylate and sepiolite has been studied using drugclay systems obtained by melting and grinding. The samples have been characterized by powder Xray diffraction, differential thermal and thermogravimetric analyses, and Vis-UV and FT-IR spectroscopies. ‘Free’ water molecules are steadily substituted by the drug molecules, without any chemical change as shown by FT-IR. The systems prepared improved the protecting ability of the pure sepiolite or the pure drug against ultraviolet radiation, especially in the so-called ‘C’ range (290-190 nm).
Twin walls and hierarchical mesoscopic structures
Authors: Salje E. K. H. , Bismayer U. , Hayward S. A. , Novak J.
Published: July 2002

Networks of interacting twin walls form hierarchical, mesoscopic structures in minerals. The typical thickness of transformation twins at T ≪ TC is ˜3 nm and increases at T → TC as . The internal structure of twin walls is derived to be chiral in systems with coupled order parameters. The effect of wall bending is discussed.
The crystal chemistry of duftite, PbCuAsO4(OH) and the β-duftite problem
Authors: Kharisun  , Taylor Max R. , Bevan D. J. M , Pring Allan
Published: July 2002

Duftite, PbCu(AsO4)(OH) is orthorhombic, space groupP212121witha= 7.768(1),b= 9. 211(1),c= 5.999(1) Å, Z = 4; the structure has been refined to R = 4.6% and Rw = 6.5% using 640 observed reflections [F> 2σ(F)]. The structure consists of chains of edge-sharing CuO6‘octahedra’, parallel to c; which are linked via AsO4tetrahedra and Pb atoms in distorted square antiprismatic co-ordination to form a three dimensional network. The CuO6‘octahedra’ show Jahn-Teller distortion with the elongation running approximately along <627>. The hydrogen bonding network in the structure was characterized using bond valence calculations. ‘β-duftite’ is an intermediate in the duftite-conichalcite series, which has a modulated structure based on the intergrowth of the two structures in domains of approximately 50 Å. The origin of the modulation is thought to be associated with displacements in the oxygen lattice and is related to the orientation of the Jahn-Teller distortion of CuO6‘octahedra’. Approximately half of the strips show an elongation parallel to <627> while the other strips are elongated parallel to [010]. This ordering results in an increase in thebcell repeat compared to duftite and conichalcite.
Tamarugite on the Isle of Wight, UK
Authors: King R. J.
Published: July 2002

Tamarugite (NaAl(SO4)2.6H2O) occurs at Compton Chine (NGR SZ 36808513), on the Isle of Wight, U.K., as globular encrustations covering an area of 2.8 m2 on argillaceous
pyritous siltstones of the Lower Greensand Group, Lower Cretaceous. It is proposed that the production of H2SO4 from oxidizing pyrite in the siltstones releases Al ions from the argillaceous sediments, the Na content being acquired from sea spray. An analogy is made between Compton Chine and an occurrence in Victoria, Australia.
Asymmetric zoning profiles in garnet from HP-HT granulite and implications for volume and grain-boundary diffusion
Authors: O’Brien P. J.
Published: July 2002

Detailed electron-microprobe line profiles and small-area compositional maps of zoned garnets in a sample of high-pressure-high-temperature granulite show features inconsistent with commonly applied diffusion models. Larger grains of an early garnet generation have their highest Ca contents in domains away from the rim or inclusions but show a sharp fall in Ca balanced by increased Mg and Fe (and slightly higher XMg) towards inclusions and the rim. In domains with secondary biotite, the sharp decrease in Ca is accompanied by variations in XMg dependent upon proximity to biotite, thus producing one-sided, asymmetric profiles with XMg lower against biotite. As a consequence, rim compositions of the same grain are different on the sides adjacent and away from biotite and there is no relationship between grain size and rim XMg. Such a zoning pattern requires that grain-boundary diffusion is as slow as volume diffusion and implies the absence of a diffusion-enhancing grain-boundary fluid phase during the majority of the rock's high-temperature exhumation history. Diffusion models ignoring this probability could yield either cooling rates that were too fast, or extrapolated ages based on closure temperature models that were too old.

A second garnet generation in the same rock, grown in a Ca-rich domain resulting from kyanite breakdown, has irregularly distributed patches, identified by compositional mapping, containing higher Ca than the first-formed garnet but at lower XMg. Use of such garnet compositions for geothermobarometrical determination of the high-pressure granulite stage would clearly lead to erroneous results. The presence of such contrasting garnet compositions in a granulite-facies rock is clearly evidence of disequilibrium, and further supports the proposition that there was a lack of an effective transport medium even at the mm scale.
Defective spectrin integrity and neonatal thrombosis in the first mouse model for severe hereditary elliptocytosis
Authors: Wandersee Nancy J. , Roesch Amanda N. , Hamblen Nancy R. , de Moes Joost , van der Valk Martin A. , Bronson Roderick T. , Gimm J. Aura , Mohandas Narla , Demant Peter , Barker Jane E.
Published: July 2002

Mutations affecting the conversion of spectrin dimers to tetramers result in hereditary elliptocytosis (HE), whereas a deficiency of human erythroid α- or β-spectrin results in hereditary spherocytosis (HS). All spontaneous mutant mice with cytoskeletal deficiencies of spectrin reported to date have HS. Here, the first spontaneous mouse mutant,sphDem/ sphDem, with severe HE is described. The sphDem mutation is the insertion of an intracisternal A particle element in intron 10 of the erythroid α-spectrin gene. This causes exon skipping, the in-frame deletion of 46 amino acids from repeat 5 of α-spectrin and alters spectrin dimer/tetramer stability and osmotic fragility. The disease is more severe insphDem/sphDem neonates than in α-spectrin–deficient mice with HS. Thrombosis and infarction are not, as in the HS mice, limited to adults but occur soon after birth. Genetic background differences that exist between HE and HS mice are suspect, along with red blood cell morphology differences, as modifiers of thrombosis timing.sphDem/sphDem mice provide a unique model for analyzing spectrin dimer- to-tetramer conversion and identifying factors that influence thrombosis.
Comparison of effects of the tyrosine kinase inhibitors AG957, AG490, and STI571 on BCR-ABL–expressing cells, demonstrating synergy between AG490 and STI571
Authors: Sun Xuemei , Layton Judith E. , Elefanty Andrew , Lieschke Graham J.
Published: July 2002

STI571 (formerly CGP57148) and AG957 are small molecule inhibitors of the protein tyrosine kinase (PTK) p145abland its oncogenic derivative p210bcr-abl. AG490 is an inhibitor of the PTK Janus kinase 2 (JAK2). No direct comparison of these inhibitors has previously been reported, so this study compared their effects on factor-dependent FDC-P1, 32D, and MO7e cells and their p210bcr-abl-expressing factor-independent derivatives. STI571 was a more potent inhibitor of3H-thymidine incorporation in p210bcr-abl-expressing cells than was AG957, and it showed superior discrimination between inhibitory effects on parental cell lines and effects on their p210bcr-abl-expressing derivatives. Assays performed with and without growth factor demonstrated that STI571 but not AG957 reversed the p210bcr-abl-driven factor independence of cell lines. p210bcr-abl-expressing cells were less sensitive to AG490 than to AG957 or STI571. However, for p210bcr-abl-expressing clones from all 3 cell lines, synergistic inhibition was demonstrated between STI571 and concentrations of AG490 with no independent inhibitory effect. Inhibition of nucleic acid synthesis with AG957 treatment was associated with reduced cell numbers, reduced viability, and small pyknotic apoptotic cells. At concentrations of STI571 that reversed the p210bcr-abl factor-independent phenotype, STI571 treatment and growth factor deprivation together were sufficient to induce apoptosis. This study concludes that, for the cell lines studied, (1) STI571 is a more potent and more selective inhibitor of a p210bcr-abl-dependent phenotype than AG957; (2) AG490 synergizes with STI571 to enhance its inhibitory effect on p210bcr-abl-driven proliferation; and (3) the combination of p210bcr-abl-tyrosine kinase inhibition and growth factor signal withdrawal can be sufficient to induce apoptotic death of transformed cells.
Erythropoiesis in the absence of janus-kinase 2: BCR-ABL induces red cell formation in JAK2−/− hematopoietic progenitors
Authors: Ghaffari Saghi , Kitidis Claire , Fleming Mark D. , Neubauer Hans , Pfeffer Klaus , Lodish Harvey F.
Published: July 2002

The receptor-associated protein tyrosine kinase janus-kinase 2 (JAK2) is essential for normal red cell development and for erythropoietin receptor (EpoR) signaling. JAK2−/− embryos are severely deficient in erythropoiesis and die at an early stage of development from fetal anemia. The binding of erythropoietin (Epo) to the EpoR triggers the activation of JAK2, the phosphorylation of the EpoR, and the initiation of the EpoR signaling cascade. In addition to Epo binding to its receptor, signaling pathways downstream of the EpoR can also be stimulated by the BCR-ABL oncoprotein. This study explored whether JAK2 is required for BCR-ABL–mediated stimulation of erythropoiesis. Here, it is shown that JAK2 is constitutively tyrosine phosphorylated in cultured and primary erythroid cells expressing BCR-ABL. However, BCR-ABL effectively supports normal erythroid proliferation, differentiation, and maturation in JAK2-deficient fetal liver cells. Using mutants of BCR-ABL, this study shows that certain signaling pathways activated by BCR-ABL segments distinct from its tyrosine kinase domain are essential for rescue of erythropoiesis in JAK2−/− progenitors. The consequences of these multiple signaling pathways for normal erythroid development are discussed.
Administration of interleukin-7 after allogeneic bone marrow transplantation improves immune reconstitution without aggravating graft-versus-host disease
Authors: Alpdogan Onder , Schmaltz Cornelius , Muriglan Stephanie J. , Kappel Barry J. , Perales Miguel-Angel , Rotolo Jimmy A. , Halm Jens A. , Rich Benjamin E. , van den Brink Marcel R. M.
Published: July 2002

Prolonged immunodeficiency after allogeneic bone marrow transplantation (BMT) causes significant morbidity and mortality from infection. This study examined in murine models the effects of interleukin-7 (IL-7) given to young and middle-aged (9-month-old) recipients of major histocompatibility complex (MHC)–matched or –mismatched allogeneic BMT. Although administration of IL-7 from day 0 to 14 after syngeneic BMT promoted lymphoid reconstitution, this regimen was ineffective after allogeneic BMT. However, IL-7 administration from day 14 (or 21) to 27 after allogeneic BMT accelerated restoration of the major lymphoid cell populations even in middle-aged recipients. This regimen significantly expanded donor-derived thymocytes and peripheral T cells, B-lineage cells in bone marrow and spleen, splenic natural killer (NK) cells, NK T cells, and monocytes and macrophages. Interestingly, although recipients treated with IL-7 had significant increases in CD4+ and CD8+ memory T-cell populations, increases in naive T cells were less profound. Most notable, however, were the observations that IL-7 treatment did not exacerbate graft-versus-host disease (GVHD) in recipients of an MHC-matched BMT, and would ameliorate GVHD in recipients of a MHC-mismatched BMT. Nonetheless, graft-versus-leukemia (GVL) activity (measured against 32Dp210 leukemia) remained intact. Although activated and memory CD4+ and CD8+ T cells normally express high levels of IL-7 receptor (IL-7R, CD127), activated and memory alloreactive donor-derived T cells from recipients of allogeneic BMT expressed little IL-7R. This might explain the failure of IL-7 administration to exacerbate GVHD. In conclusion, posttransplant IL-7 administration to recipients of an allogeneic BMT enhances lymphoid reconstitution without aggravating GVHD while preserving GVL.
Clinical, immunologic, and pathologic correlates of bone marrow involvement in 291 patients with acquired immunodeficiency syndrome–related lymphoma
Authors: Seneviratne Lasika , Espina Byron M. , Nathwani Bharat N. , Chan Joel A. , Brynes Russell K. , Levine Alexandra M.
Published: July 2002

Bone marrow involvement is reported in approximately 25% of patients with newly diagnosed acquired immunodeficiency syndrome–related lymphoma (ARL). Studied were 291 patients with ARL, diagnosed and treated at one medical center between 1984 and 1998. Clinical, immunologic, and pathologic characteristics of patients with bone marrow involvement were compared with those of patients without marrow involvement. Bone marrow involvement was present in 55 patients (19%). Small noncleaved lymphoma was diagnosed in 38% of the entire group and was the most common pathologic subtype in patients with bone marrow involvement (55% versus 34%;P = .008). Analysis of complete blood counts revealed a median hemoglobin level of 10.6 g/dL in both marrow-positive and marrow-negative groups. In contrast, a platelet count lower than 100 000/μL was more common in patients with bone marrow involvement (27% versus 11%; P = .02). Patients with marrow involvement were more likely to have leptomeningeal (cerebrospinal fluid [CSF]) lymphoma than patients whose marrows were uninvolved (24% versus 7%; P < .001) and were also more likely to have high lactate dehydrogenase (LDH) (P = .002), bone involvement (P < .001), and/or systemic B symptoms including fever, night sweats, and/or weight loss (P = .05). Median survival did not differ between marrow-positive and marrow-negative groups. On multivariate analysis, factors associated with decreased survival of marrow-positive patients included greater than 50% involvement (P = .002), systemic B symptoms (P = .008), and high-grade histologic type (P = .035). Marrow involvement in ARL correlates with small noncleaved pathology, thrombocytopenia lower than 100 000 mm3, high LDH, and lymphomatous involvement of the CSF. Survival is statistically shorter in patients with greater than 50% marrow involvement, high-grade pathology, and/or systemic B symptoms.
TEL/platelet-derived growth factor receptor β activates phosphatidylinositol 3 (PI3) kinase and requires PI3 kinase to regulate the cell cycle
Authors: Dierov Jamil , Xu Qing , Dierova Raia , Carroll Martin
Published: July 2002

TEL/platelet-derived growth factor receptor β (PDGFβR) is the protein product of the t(5;12) translocation in chronic myelomonocytic leukemia. TEL/PDGFβR transforms interleukin-3 (IL-3)–dependent Ba/F3 and 32D cells to IL-3 independence and induces a murine myeloproliferative disease in a bone marrow transplantation model of leukemogenesis. The fusion protein encodes a constitutively activated, cytoplasmic tyrosine kinase that activates multiple signal transduction pathways. To identify the signaling pathways that are necessary for transformation by TEL/PDGFβR, transformed Ba/F3 and 32D cells were studied. TEL/PDGFβR activates the kinase activity of phosphatidylinositol-3 (PI3) kinase and stimulates phosphorylation of its downstream substrates, including Akt and p70S6 kinase. Activation of this pathway requires the kinase activity of TEL/PDGFβR and is inhibited by the PDGFβR inhibitor, STI571. Furthermore, inhibition of PI3 kinase with the pharmacologic inhibitor, LY294002, inhibits growth of the transformed cells. Treated cells arrest in the G1 phase of the cell cycle within 16 hours but do not undergo apoptosis. To study the mechanism of cell cycle arrest by LY294002, the activity of the cdk4 complex, which regulates the transit of cells from the G1 to S phase in hematopoietic cells, was examined. Both STI571 and LY294002 lead to a decrease in the activity of cdk4 kinase activity and a decrease in expression of both Cyclin D2 and Cyclin E within several hours. These studies demonstrate the presence of a signaling pathway from TEL/PDGFβR to PI3 kinase and subsequently to regulation of the cdk4 kinase complex. Activation of this pathway is necessary for transformation by TEL/PDGFβR.