bluuebunny/crossref_metadata_2025 huggingface dataset:
Kaposi's Sarcoma-Associated Herpesvirus-Encoded G Protein-Coupled Receptor ORF74 Constitutively Activates p44/p42 MAPK and Akt via Giand Phospholipase C-Dependent Signaling Pathways
Authors: Smit Martine J. , Verzijl Dennis , Casarosa Paola , Navis Marjon , Timmerman Henk , Leurs Rob
Published: July 2002

The G protein-coupled receptor encoded by Kaposi's sarcoma-associated herpesvirus, also referred to as ORF74, has been shown to stimulate oncogenic and angiogenic signaling pathways in a constitutively active manner. The biochemical routes linking ORF74 to these signaling pathways are poorly defined. In this study, we show that ORF74 constitutively activates p44/p42 mitogen-activated protein kinase (MAPK) and Akt via Gi- and phospholipase C (PLC)-mediated signaling pathways. Activation of Akt by ORF74 appears to be phosphatidylinositol 3-kinase (PI3-K) dependent but, interestingly, is also mediated by activation of protein kinase C (PKC) and p44/p42 MAPK. ORF74 may signal to Akt via p44/p42 MAPK, which can be activated by Gi, through activation of PI3-K or through PKC via the PLC pathway. Signaling of ORF74 to these proliferative and antiapoptotic signaling pathways can be further modulated positively by growth-related oncogene (GROα/CXCL1) and negatively by human gamma interferon-inducible protein 10 (IP-10/CXCL10), thus acting as an agonist and an inverse agonist, respectively. Despite the ability of the cytomegalovirus-encoded chemokine receptor US28 to constitutively activate PLC, this receptor does not increase phosphorylation of p44/p42 MAPK or Akt in COS-7 cells. Hence, ORF74 appears to signal through a larger diversity of G proteins than US28, allowing it to couple to proliferative and antiapoptotic signaling pathways. ORF74 can therefore be envisioned as an attractive target for novel treatment of Kaposi's sarcoma.
Therapeutic Immunization with a Virion Host Shutoff-Defective, Replication-Incompetent Herpes Simplex Virus Type 1 Strain Limits Recurrent Herpetic Ocular Infection
Authors: Keadle Tammie L. , Morrison Lynda A. , Morris Jessica L. , Pepose Jay S. , Stuart Patrick M.
Published: July 2002

Immunization of mice with herpes simplex virus type 1 (HSV-1) mutant viruses containing deletions in the gene for virion host shutoff (vhs) protein diminishes primary and recurrent corneal infection with wild-type HSV-1. vhs mutant viruses are severely attenuated in vivo but establish latent infections in sensory neurons. A safer HSV-1 mutant vaccine strain, Δ41Δ29, has combined vhs and replication (ICP8−) deficits and protects BALB/c mice against primary corneal infection equivalent to a vhs−strain (BGS41). Here, we tested the hypothesis that Δ41Δ29 can protect as well as BGS41 in a therapeutic setting. Because immune response induction varies with the mouse and virus strains studied, we first determined the effect of prophylactic Δ41Δ29 vaccination on primary ocular infection of NIH inbred mice with HSV-1 McKrae, a model system used to evaluate therapeutic vaccines. In a dose-dependent fashion, prophylactic Δ41Δ29 vaccination decreased postchallenge tear film virus titers and ocular disease incidence and severity while eliciting high levels of HSV-specific antibodies. Adoptive transfer studies demonstrated a dominant role for immune serum and a lesser role for immune cells in mediating prophylactic protection. Therapeutically, vaccination with Δ41Δ29 effectively reduced the incidence of UV-B-induced recurrent virus shedding in latently infected mice. Therapeutic Δ41Δ29 and BGS41 vaccination decreased corneal opacity and delayed-type hypersensitivity responses while elevating antibody titers, compared to controls. These data indicate that replication is not a prerequisite for generation of therapeutic immunity by live HSV mutant virus vaccines and raise the possibility that genetically tailored replication-defective viruses may make effective and safe therapeutic vaccines.
Constitution and HPLC Resolution of Enantiomers of the [8,4'-μ-R2N-commo-(1,2-C2B9H10)2-3-Co] Complexthe Third Isomer of Nitrogen-Bridged Bis
Authors: Plešek Jaromír , Grüner Bohumír , Heřmánek Stanislav , Fusek Jiří , Votavová Hana
Published: July 2002

A fully asymmetric structure of the [4,8'-μ-R2N-commo-(1,2-C2B9H10)2-3-Co] (R = H and Me) cobaltacarborane complexes with a monoatomic nitrogen bridge between both ligands was determined by high resolution mass spectrometry and 1H, 11B NMR, [11B-11B] COSY NMR spectroscopy. Their structures have been also supported by the resolution of both compounds into enantiomers on the β-cyclodextrin HPLC column. A complex reaction of the [3-Co-commo-(1,2-C2B9H11)2]- ion with the NO+ cation is briefly discussed and the tentative structure of the second main product is also suggested.
Mesomorphic Behaviour of Saturated and Monounsaturated C18 and C22 Fatty Acid Esters of Cholesterol
Authors: Pirkl Slavomír
Published: July 2002

The phase transitions and effective optical rotary power of saturated and monounsaturated aliphatic esters of cholesterol with 18 and 22 carbon atoms in the chain have been described. The effect of cis/trans isomerism on these properties is discussed.
Theoretical Treatment of Rapid Sorption Kinetics Measured in Batch Arrangement
Authors: Micke André , Struve Peter , Kočiřík Milan , Zikánová Arlette
Published: July 2002

Universal solution of a family of sorption kinetic models which are based on superposition principle has been developed to describe sorption experiments in a closed system. The models account for the interactions of a sorbate sorbent system with the apparatus which arise (i) from the mass balance condition in a closed system and (ii) from a finite rate of sorbate supply to the sorbent, the latter effect being of importance particularly in rapid nonstationary kinetic processes. Theoretical uptake curves for the intracrystalline sorption kinetics in zeolite crystals are exemplified using numerical solution of the corresponding Volterra integral equations which represent kinetic models of the overall transient sorption process in the apparatus. The approach appears to be promising for treatment of sorption kinetics in multicomponent systems.
Phenomenon of Turbulent Macro-Instabilities in Agitated Systems
Authors: Brůha Oldřich , Fořt Ivan , Smolka Pavel
Published: July 2002

Turbulent macro-instabilities in the process of mixing in cylindrical baffled vessel provided with pitched blade impeller were studied. Rules of macro-instability occurrence were investigated in their dependence on physical parameters of three Newtonian liquids mixed and on the regime of mixing. The observations were realized partly visually, partly by means of a specially designed mechanical measuring device connected with an electronic recorder indicating the manifestations of instability in the liquid.
Dipole Moments of para-Substituted N-Phenylsulfonyl-N'-Allylthioureas
Authors: Suchár Gejza , Danihel Ivan
Published: July 2002

Dipole moments of a series of para-substituted N-phenylsulfonyl-N'-allylthioureas were determined. Comparison of the experimentally found dipole moments with those calculated by vector addition of bond and group moments has shown that (E) conformation at the N-C bonds is preferred. The same result was obtained from the N-H stretching vibrations. The results are compatible with a synperiplanar arrangement at the C-C bond of the allyl moiety.
Bare Molecular Anions of Unsaturated Hydrocarbons: Density Functional Charge and Spin Distributions Based on Their Single Crystal Structures
Authors: Havlas Zdeněk , Bock Hans
Published: July 2002

Bare π-hydrocarbon radical anions M•, dianions M− as well as even a radical trianion M• can be crystallized as alkali metal salts, [M(•)−n][Me+solv]n if the solvent-shared contact ion multiples, [M(•)−n..(Me+)n]solv, present in aprotic solution after the reduction at an alkali metal mirror can be separated by advantageous cation solvation. Altogether 22 π-hydrocarbon anions M(•)−n comprising polycyclic cata- as well as peri-annelated six-membered ring compounds, polyphenyls, those with nonalternant polycyclic skeletal topology, open chain and organosilicon derivatives have been characterized by low-temperature X-ray crystallographic analyses. Based on the structural data determined, their charge and spin populations have been approximated by density functional calculations including natural bond orbital analyses (DFT/NBO). Although in general the total (σ + π) charges at individual C centers of the hydrocarbon skeletons cannot be correlated neither with the structural data nor with the spin distribution, numerous interesting details as well as some useful rules are provided. They concern, for instance, central C-C bond elongation and peripheral C-C bond shortening, preferred charge localization patterns, effects of conformational changes in the π-radical anions crystallized or Jahn-Teller distortions of formally degenerate molecular radical anion states.
Erythrocyte Membrane Fluidity in Diabetics: Fluorescence Study
Authors: Jakuš Vladimír , Fuhr Uwe , Wörner Wolfgang , Rietbrock Norbert
Published: July 2002

Erythrocyte membrane fluidity is changed in diabetic subjects with long-term complications. As membrane fluidity indicator, the mean steady-state fluorescence anisotropy was measured in 1,6-diphenylhexa-1,3,5-triene labelled erythrocyte membranes prepared from six control healthy donors and six poorly controlled diabetic subjects. Fluorescence anisotropy values of membranes prepared from erythrocytes of diabetic subjects were significantly higher than in control subjects. This indicates a decreased fluidity of membranes prepared from diabetic subjects. The decreased fluidity of diabetic membranes was raised by glycation inhibitors - penicillamine, captopril, and lipoic acid.
An Alternative Approach to Chiral 2-[1'-(Diphenylphosphanyl)ferrocenyl]-4,5-dihydrooxazoles
Authors: Drahoňovský Dušan , Císařová Ivana , Štěpnička Petr , Dvořáková Hana , Maloň Petr , Dvořák Dalimil
Published: July 2002

The reaction of 1'-(diphenylphosphanoyl)ferrocenecarbonyl chloride, generated in situ by the reaction of 1'-(diphenylphosphanoyl)ferrocenecarboxylic acid and oxalyl chloride, with chiral aminoalcohols gave amidoalcohols [Fe(η5-C5H4P(O)Ph2)(η5-C5H4C(O)NHCHRCH2OH)] 13, (R = i-Pr, (S); R = i-Pr, (R); R = t-Bu, (S) and R = Ph, (R). The amidoalcohols 13 were converted to 2-[1'-(diphenylphosphanoyl)ferrocen-1-yl]-4,5-dihydrooxazoles 14 by ring-closing reaction with a tosyl chloride-triethylamine mixture. Subsequent reduction of 14 with trichlorosilane in the presence of triethylamine afforded the corresponding 2-[1'-(diphenylphosphanyl)ferrocenyl]-4,5-dihydrooxazoles 10. Compounds 13d, 14d and 10d were subjected to a detailed 1H, 13C and 31P NMR analyses. CD spectra of all 10 were measured. trans-Dichlorobis{(S)-2-[1'-(diphenylphosphanyl)ferrocenyl]-4-isopropyl-4-5-dihydrooxazole-κP}palladium(II) (15) was synthesised and its solid-state structure was determined by single-crystal X-ray diffraction.
A Time-Resolved Low-Angle Light Scattering Apparatus. Application to Phase Separation Problems in Polymer Systems
Authors: Koňák Čestmír , Holoubek Jaroslav , Štěpánek Petr
Published: July 2002

A time-resolved small-angle light scattering apparatus equipped with azimuthal integration by means of a conical lens or software analysis of scattering patterns detected with a CCD camera was developed. Averaging allows a significant reduction of the signal-to-noise ratio of scattered light and makes this technique suitable for investigation of phase separation kinetics. Examples of applications to time evolution of phase separation in concentrated statistical copolymer solutions and dissolution of phase-separated domains in polymer blends are given.
Anthropometric characteristics of elite male junior rowers
Authors: Bourgois Jan , Claessens Albrecht L , Vrijens Jacques , Philippaerts Renaat , Van Renterghem Bart , Thomis Martine , Janssens Melissa , Loos Ruth , Lefevre Johan
Published: July 2002

During the 1997 Fédération Internationale des Sociétés d'Aviron World Junior Rowing Championships, anthropometric data on 383 male junior rowers were assessed. With 430 participating athletes, the sample represented 89% of the population. In addition to age, 27 dimensions were measured: body mass, six heights or lengths, four breadths, 10 girths, and six skinfolds. The elite male junior rowers were tall (187.4 (5.8) cm; mean (SD)) and heavy (82.2 (7.4) kg), with larger length, breadth, and girth dimensions than a nationally representative sample of Belgian boys of the same chronological age. A rowing specific anthropometric profile chart with norms was constructed. The stature of the junior rowers is similar to that of adult heavyweight elite rowers, except that the junior rowers are lighter. Compared with non-finalists, finalists are heavier (but still lighter than the adult heavyweight elite rower) and taller, with greater length, breadth (except for the bicristal diameter), and girth dimensions.
Spondylolysis: a critical review
Authors: Standaert C J , Herring S A
Published: July 2002

Aim—To provide an understanding of the current concepts in the natural history, pathophysiology, diagnosis, and treatment of spondylolysis based on the available medical literature.

Methods—Articles were selected for review by the following methods: (a) MEDLINE searches with review of abstracts to select relevant articles; (b) review of multiple textbooks considered likely to contain information on spondylolysis; (c) review of references in articles identified by (a) and (b). Over 125 articles were ultimately reviewed fully. Publications were selected for inclusion in this article on the basis of perceived scientific and historical merit, particularly as thought to be relevant to achieving the stated purpose of this review. As no controlled clinical trials were identified, this could not be used as an inclusion criterion.

Conclusions—Isthmic spondylolysis is considered to represent a fatigue fracture of the pars interarticularis of the neural arch. There is a relatively high incidence of radiographically identified spondylolysis in the general population, but the vast majority of these lesions probably occur without associated symptoms. Symptomatic pars lesions appear to be particularly a clinical problem in adolescents, especially adolescent athletes. The optimal diagnostic and treatment algorithms are not well identified in the current literature. Multiple imaging studies may have a role in the diagnosis of a pars lesion, and treatment seems likely to require at least relative rest and physical rehabilitation with consideration of bracing or, rarely, surgical intervention depending on the clinical context.
When to retire after concussion?
Authors: McCrory Paul
Published: July 2002

This article has been retracted. See the retraction notice for details. The PDF is retained for transparency.
Case-control study of leatherwork and male infertility
Authors: Kurinczuk J J , Clarke M
Published: July 2002

OBJECTIVES

To test the hypothesis that leatherwork is associated with male infertility mediated through the development of oligozoospermia. The basis of any association was postulated, at the outset, to be with exposure to the solvents used in leatherwork.

METHODS

All new referrals with infertility presenting in Leicestershire hospital clinics between November 1988 and September 1992 and Kettering District General Hospital from August 1990 were eligible to participate; 88.5% agreed to be interviewed. Exposure to leatherwork and work with solvents was defined by job title. Comparisons were made with fertile controls and in an analysis within men from infertile couples with oligozoospermia as the primary outcome. Effects on sperm motility and deformity were investigated secondarily. Analyses used logistic regression for binary outcomes and multilevel modelling for continuous outcomes.

RESULTS

1906 men were interviewed. Compared with the fertile controls the men from infertile couples were 1.10 times (95% confidence interval (95% CI) 0.46 to 2.63; p=0.99) more likely to be leatherworkers and 1.73 times (95% CI 1.26 to 2.38; p<0.001) more likely to work with solvents. Compared with other men, leatherworkers were 1.20 times (95% CI 0.43 to 3.33; p=0.73) more likely to present with oligozoospermia and 1.65 times (95% CI 0.37 to 7.30; p=0.51) more likely to present with teratozoospermia. Being a leatherworker was associated with only a 6% reduction in sperm concentration; motility and deformity were similarly unaffected by this exposure. Work with solvents did not statistically, nor clinically, increase the risk of oligozoospermia, teratozoospermia, or asthenozoospermia.

CONCLUSIONS

There was little evidence to support the hypothesis that leatherwork is associated with an increased risk of presenting with infertility or oligozoospermia. There was limited evidence that leatherwork is a risk factor for teratozoospermia. Workers with solvents were at an increased risk of presenting with infertility, although this was not mediated through effects on standard measures of semen quality; this finding merits further investigation.
Sperm count and chromatin structure in men exposed to inorganic lead: lowest adverse effect levels
Authors: Bonde J P , Joffe M , Apostoli P , Dale A , Kiss P , Spano M , Caruso F , Giwercman A , Bisanti L , Porru S , Vanhoorne M , Comhaire F , Zschiesche W
Published: July 2002

Objectives: To obtain knowledge on male reproductive toxicity of inorganic lead at current European exposure levels and to establish lowest adverse effect levels, if any.

Methods: A cross sectional survey of the semen of 503 men employed by 10 companies was conducted in the United Kingdom, Italy, and Belgium. The mean blood lead concentration was 31.0 μg/dl (range 4.6–64.5) in 362 workers exposed to lead and 4.4 μg/dl (range below the detection limit of 19.8) in 141 reference workers. Semen volume and sperm concentration were determined in a fresh semen sample according to an agreed protocol subject to quality assurance. The sperm chromatin structure assay (SCSA) was performed at a centralised laboratory. Extraneous determinants including centre, period of sexual abstinence, and age were taken into account in the statistical analysis. If appropriate, possible thresholds were examined by iterative threshold slope linear regression.

Results: The median sperm concentration was reduced by 49% in men with blood lead concentration above 50 μg/dl. There was no indication of a linear trend of lower sperm concentration with increasing blood lead values, but threshold slope least square regression identified a blood lead concentration of 44 μg/dl (β=−0.037,F=4.35, p=0.038) as a likely threshold. Abnormal sperm chromatin structure was not related to blood lead concentration, but some indications of deterioration of sperm chromatin was found in men with the highest concentrations of lead within spermatozoa. Biological monitoring data did not indicate long term effects of lead on semen quantity or sperm chromatin.

Conclusion: Adverse effects of lead on sperm concentration and susceptibility to acid induced denaturation of sperm chromatin are unlikely at blood lead concentrations below 45 μg/dl. Effects of low level exposure to lead on other measures of testicular function cannot be ruled out.
Inflammatory bowel disease in pregnancy
Authors: Alstead E M
Published: July 2002

Concerns about sexual health, fertility, and pregnancy are common in patients with inflammatory bowel disease (IBD). Fertility is usually normal, although may be decreased in women with active Crohn’s disease. Women with active IBD (especially Crohn’s disease) are at risk of having small and premature babies. In some patients with IBD it may be desirable to continue drug treatment during pregnancy in order to control disease activity. Early engagement in discussion of these issues is important and it should be possible for most patients with IBD to have a normal outcome of pregnancy.
Long term and transitional intermittent smokers: a longitudinal study
Authors: Lindström M , Isacsson S-O ,   The Malmö Shoulder-Neck Study Group
Published: July 2002

Objective: To investigate differences in snuff consumption, sociodemographic and psychosocial characteristics between baseline intermittent smokers that had become daily smokers, stopped smoking or remained intermittent smokers at the one year follow up.

Design/setting/participants/measurements: A population of 12 507 individuals interviewed at baseline in 1992-94 and at a one year follow up, aged 45–69 years, was investigated in a longitudinal study. The three groups of baseline intermittent smokers were compared to the reference population (all others) according to sociodemographic, psychosocial, and snuff consumption characteristics. A multivariate logistic regression model was used to assess differences in psychosocial conditions, adjusting for age, sex, country of origin, marital status, education, and snuff consumption.

Results: 60% of all baseline intermittent smokers had remained intermittent smokers, 16% had become daily smokers, and 24% had stopped smoking at the one year follow up. The long term intermittent smokers and those who had stopped smoking were young, unmarried, highly educated, and snuff consumers to a higher extent than the reference population. They also had more psychosocial resources than the reference population, while the psychosocial resources of those who had become daily smokers were poorer.

Conclusions: The majority of intermittent smokers are long term intermittent smokers. The results suggest that long term intermittent smokers have other psychosocial characteristics than daily smokers.
THE FASTEST AND SHORTEST ALGORITHM FOR ALL WELL-DEFINED PROBLEMS
Authors: HUTTER MARCUS
Published: July 2002

An algorithm M is described that solves any well-defined problem p as quickly a the fastest algorithm computing a solution to p, save for a factor of 5 and low-order additive terms. M optimally distributes resources between the execution of provably correct p-solving programs and an enumeration of all proofs, including relevant proofs of program correctness and of time bounds on program runtimes. M avoids Blum's speed-up theorem by ignoring programs without correctness proof. M has broader applicability and can be faster than Levin's universal search, the fastest method for inverting functions save for a large multiplicative constant. An extension of Kolmogorov complexity and two novel natural measures of function complexity are used to show the most efficient program computing some function f is also among the shortest programs provably computing f.
BOUNDARY VALUE PROBLEM FOR THE WAVE EQUATIONS
Authors: HILLION P.
Published: July 2002

We consider the stationary wave solutions of the wave equation propagating along the z direction and we discuss the boundary value problem when the boundary function is given on a space-time hypersurface [Formula: see text] with equation [Formula: see text]. An explicit solution is obtained when [Formula: see text] is either a cylindrical surface with axis along x or y on a surface of revolution around z−ct.
CANONICALLY COVARIANT FORMULATION OF LANDAU'S NEWTONIAN SUPERFLUID DYNAMICS
Authors: CARTER B. , KHALATNIKOV I. M.
Published: July 2002

The classical Landau theory of perfect (i.e. conservative) two-constituent superfluid dynamics in Newton space-time is radically reformulated in a canonical presentation that helps to reveal symmetries and conservation properties (notably those of the thermal vorticity and helicity) that are obscured in the traditional treatment. This presentation uses a four-dimensional terminology that is more concise and elegant than the traditional 3 + 1 description and that simplifies the description of transformation properties under the action of the Milne group (i.e. the nonlinear generalization of the Galilei group).
THE RANGE OF VALUES OF λ2/λ1 AND λ3/λ1 FOR THE FIXED MEMBRANE PROBLEM
Authors: ASHBAUGH MARK S. , BENGURIA RAFAEL D.
Published: July 2002

We investigate the region of the plane in which the point (λ2/λ1, λ3/λ1) can lie, where λ1, λ2, and λ3 are the first three eigenvalues of the Dirichlet Laplacian on an arbitrary bounded domain Ω ⊂ ℝ2. In particular, by making use of a technique introduced by de Vries we obtain the best bounds to date for the quantities λ3/λ1 and (λ2 + λ3)/λ1. These bounds are λ3/λ1 ≤ 3.90514+ and (λ2 + λ3)/λ1 ≤ 5.52485+ and give small improvements over previous bounds of Marcellini. Where Marcellini used a bound due to Brands in his argument we use a better version of this bound which we obtain by incorporating deVries' idea. The other bounds that yield the greatest information about the region where points (λ2/λ1, λ3/λ1) can (possibly) lie are those due to Marcellini, Hile and Protter, and us (of which there are several, with two of them being new with this paper).
GRAVITY INDUCED NONCOMMUTATIVE SPACETIME
Authors: FREDENHAGEN K.
Published: July 2002

Basic physical principles imply uncertainties for position measurements. A noncommutative spacetime is found which exhibits these uncertainties.
DIMENSIONAL REDUCTION, ${\rm SL} (2, {\mathbb C})$-EQUIVARIANT BUNDLES AND STABLE HOLOMORPHIC CHAINS
Authors: ÁLVAREZ-CÓNSUL LUIS , GARCÍA-PRADA OSCAR
Published: July 2002

In this paper we study gauge theory on [Formula: see text]-equivariant bundles over X × ℙ1, where X is a compact Kähler manifold, ℙ1 is the complex projective line, and the action of [Formula: see text] is trivial on X and standard on ℙ1. We first classify these bundles, showing that they are in correspondence with objects on X — that we call holomorphic chains — consisting of a finite number of holomorphic bundles ℰi and morphisms ℰi → ℰi-1. We then prove a Hitchin–Kobayashi correspondence relating the existence of solutions to certain natural gauge-theoretic equations and an appropriate notion of stability for an equivariant bundle and the corresponding chain. A central tool in this paper is a dimensional reduction procedure which allow us to go from X × ℙ1 to X.
ON PERSISTENCE IN MULTIOBJECTIVE OLIGOPOLY
Authors: AHMED E. , HEGAZI A. S. , ABD EL-HAFEZ A. T.
Published: July 2002

Multiobjective oligopoly models are constructed. The objective of the first two models are to maximize profits and to maximize sales. In the third model, the objectives are to maximize profits and to minimize risk. Giving more weight to risk minimization decreased the profits. In all the three models, we found that the weight of the profit maximization has to be higher than a given threshold. Sufficient conditions for persistence of some multiobjective oligopolies are derived. Again, they require that the weight of profit maximization to be higher than certain value.
TYPE-II QUANTUM COMPUTERS
Authors: YEPEZ JEFFREY
Published: July 2002

This paper discusses a computing architecture that uses both classical parallelism and quantum parallelism. We consider a large parallel array of small quantum computers, connected together by classical communication channels. This kind of computer is called a type-II quantum computer, to differentiate it from a globally phase-coherent quantum computer, which is the first type of quantum computer that has received nearly exclusive attention in the literature. Although a hybrid, a type-II quantum computer retains the crucial advantage allowed by quantum mechanical superposition that its computational power grows exponentially in the number of phase-coherent qubits per node, only short-range and short time phase-coherence is needed, which significantly reduces the level of engineering facility required to achieve its construction. Therefore, the primary factor limiting its computational power is an economic one and not a technological one, since the volume of its computational medium can in principle scale indefinitely.
Anti-Hypertensive Effect of Water Extract of Danshen on Renovascular Hypertension Through Inhibition of the Renin Angiotensin System
Authors: Kang Dae Gill , Yun Yong Gab , Ryoo Jang Hyun , Lee Ho Sub
Published: July 2002

A study was designed to elucidate the mechanism of anti-hypertensive effects of Danshen in the two-kidney, one clip (2K1C) Goldblatt renovascular hypertensive model, which is the renin-angiotensin system (RAS)-dependent hypertensive model. We investigated the effects of water extracts of Danshen on the angiotensin converting enzyme (ACE) activities, systolic blood pressure (SBP), and hormone levels in the plasma of 2K1C rats. ACE activity was inhibited by the addition of Danshen extract in a dose-dependent manner. SBP was decreased significantly after administration of Danshen extract in 2K1C, whereas plasma renin activity (PRA) was not changed. The plasma concentration of aldosterone (PAC) was decreased significantly in 2K1C group administered with Danshen extract, whereas the plasma concentration of ANP was increased by administration of Danshen extract for three weeks. These results suggest that Danshen has an anti-hypertensive effect through the inhibition of ACE, an essential regulatory enzyme of RAS.
THE INTERFACE OF COSMOLOGY WITH STRING AND M(ILLENNIUM) THEORY
Authors: EASSON DAMIEN A.
Published: July 2002

The purpose of this review is to discuss recent developments occurring at the interface of cosmology with string and M theory. We begin with a short review of 1980s string cosmology and the Brandenberger–Vafa mechanism for explaining space–time dimensionality. It is shown how this scenario has been modified to include the effects of p-brane gases in the early universe. We then introduce the Pre-Big-Bang scenario (PBB), Hořava–Witten heterotic M theory and the work of Lukas, Ovrut and Waldram, and end with a discussion of large extra dimensions, the Randall–Sundrum model and Brane World cosmologies.
THE BTEV TRIGGERS AND DATA ACQUISITION SYSTEMS
Authors:   Representing the BTeV Collaboration., LEBRUN PAUL
Published: July 2002

A coherent and complete suite of triggers and data compression stages for the BTeV experiment has been designed and prototyped. Level 1 considers all crossings, finds primary vertices, and searches for detached tracks from these primary vertives using only the pixel vertex detector. Muons with a relatively high transverse momentum will also be identified at that stage. Level 1 runs on dedicated processors. Level 2 selects events based on the pixel and the forward tracking systems, and will run on a conventional processor farm. Level 3 will use the complete BTeV detector information to reduce the background by a factor of factor 2 to 5 and to reduce significantly the event size.
RECENT RESULTS FROM THE CERN NA44 EXPERIMENT
Authors:   For the NA44 Collaboration, HUMANIC T. J.
Published: July 2002

Recent results for two boson interferometry from CERN experiment NA44 are presented. Experiment NA44 is a focussing spectrometer with both excellent momentum resolution and particle identification. The most recent results shown will be two-pion and two-kaon correlations from 158 GeV/nucleon Pb+Pb running. The systematics of the NA44 two-boson results are described rather well by a final-state rescattering model.
POSSIBILITY OF TURBULENT CRYSTALS
Authors: YUKALOV V. I. , YUKALOVA E. P.
Published: July 2002

The possibility for the occurrence in crystals of a phenomenon, resembling turbulence, is discussed. This phenomenon, called heterophase turbulence, is manifested by the fluctuational appearance inside a crystalline sample of disordered regions randomly distributed in space. The averaged picture for such a turbulent solid is exemplified by an exactly solvable lattice-gas model. The origin of heterophase turbulence is connected with stochastic instability of quasi-isolated systems.
COMPUTER SIMULATION OF EPITAXIAL GROWTH OF SILICON ON Si (001) SURFACE
Authors: LIANG M. H. , XIE X. , LI S.
Published: July 2002

Epitaxial growth of silicon on Si (001) surface has been studied with interatomic potential based molecular dynamics simulation method. Three silicon interatomic potentials developed separately by Stillinger-Weber, Tersoff, and Bazant-Kaxiras were used. Energetic beam of 8 eV, substrate temperature of 500K and deposition rate of 1.15 ps/atom were used as the deposition conditions. Morphologies of the growth were obtained and densities in the growth direction analyzed. Epitaxial growth under the deposition conditions imposed was found possible only using the Stillinger-Weber potential. Disordered growths of differing degree were obtained using the Bazant-Kaxiras and Tersoff potentials. The disordered growth may be attributed to the existence of an epitaxial transition temperature higher than 500K that these potentials might have.
INTERACTIONS OF ORGANIC ADDITIVES WITH IONIC CRYSTAL HYDRATES: THE IMPORTANCE OF THE HYDRATED LAYER
Authors: FÜREDI-MILHOFER H. , SIKIRIĆ M. , TUNIK L. , FILIPOVIĆ-VINCEKOVIĆ N. , GARTI N.
Published: July 2002

The interactions of two groups of hydrated model crystals, calcium hydrogenphosphate dihydrate (DCPD) vs. octacalcium phosphate (OCP) and calcium oxalate monohydrate (COM) vs. calcium oxalate dihydrate (COD) with different organic additives are considered. DCPD precipitates as platelet-like crystals with the dominant faces shielded by hydrated layers and charged lateral faces. In the second system COM has charged surfaces, while all faces of COD are covered with layers containing water molecules. The organic molecules tested include negatively charged, flexible and rigid small and macromolecules (glutamic and aspartic acid, citrate, hexaammonium polyphosphate, phytate and polyaspartate) and anionic surfactants (sodium dodecyl sulphate, SDS, sodium diisooctyl sulfosuccinate, AOT, sodium cholate NaC and disodium oleoamido PEG-2 sulfosuccinate, PEG). Two types of effects have been demonstrated: (1) Effect on crystal growth morphology: Flexible organic molecules with high charge density and anionic surfactants affected the growth morphology of DCPD and COM by selectively interacting with the charged lateral faces while rigid molecules (phytate, polyaspartate) specifically recognized the dominant (010) face of DCPD due to structural and stereochemical compatibility. (2) Effect on phase composition: Anionic surfactants at concentrations above the cmc promoted growth of OCP and COD respectively by selectively adsorbing at, and inhibiting growth oif nuclei of DCPD and/or COM, which were dominant in the respective control systems. The effect was especially pronounced in the calcium oxalate precipitation system, where in some cases complete reversal of the phase composition occurred. The important role of the hydrated layer, as part of the structure of the investigated crystal hydrates, in the above crystal additive interactions is discussed.
CARBON NITRIDE THIN FILMS DEPOSITED BY CATHODIC ELECTRODEPOSITION
Authors: Cao Chuanbao , Fu Jiyu , Zhu Hesun
Published: July 2002

Carbon nitride thin films were prepared by cathodic electrodeposition. The dicyandiamide compound dissovled in acetone was selected as the organic precursor. Single crystal silicon wafers and conductive glass (ITO) wafers were used as substrates. XPS measurements indicated that the films composed of carbon and nitrogen elements. The nitrogen content reached 41%. The polycrystalline β-C3N4 should exit in the prepared film from TED measurements. The nano hardness of the films on ITO substrates were as high as 13 GPa. The structure and properties were studies.
COMPUTER SIMULATION EVIDENCE FOR A BEREZHINSKIĪ –KOSTERLITZ–THOULESS-LIKE TRANSITION IN A TWO-DIMENSIONAL LATTICE-GAS MODEL
Authors: ROMANO S.
Published: July 2002

We have considered a classical lattice-gas model, consisting of a two-dimensional lattice Z2, each site of which hosts at most one two-component unit vector; particles occupying pairs of nearest-neighbouring sites interact via the ferromagnetic potential [Formula: see text] where νj=0,1 denotes occupation numbers, uj are the unit vectors (classical spins) and ∊ is a positive constant setting energy and temperature scales; the total Hamiltonian is given by [Formula: see text] where ∑{j<k} denotes sum over all distinct nearest-neighbouring pairs of lattice sites. The saturated-lattice version of this model, where all sites are occupied, supports the well-known Berezhinskiĭ–Kosterlitz–Thouless transition; we report here a simulation study, carried out for both μ= 0.1 and μ=-0.2, showing evidence of a transition of this kind, in broad qualitative agreement with previous Renormalization-Group studies.
T-O, OII-OIII and OIII-OI Phase Boundary in Oxygen-Chain-Equalised and Order-Stabilised Polycrystalline Pair Samples of YBa2Cu3O6+x
Authors: Calestani G. , Manca P. , Sanna S. , Migliori A.
Published: July 2002

A comparative investigation, performed on Oxygen-Chain-equalised(k) Deintercalated [ OCD ] k and Intercalated [ OCD ] k pair-samples ( k -pairs) of YBa 2 Cu 3 O 6+x by resistive T c and electron diffraction (ED) at steps Δk=0.02-0.03, revealed that equivalent or non-equivalent microscopic oxygen-chain arrangements are produced, at the same oxygen content k, by intercalation and deintercalation of oxygen in the Cu(1)Ox chains. These arrangements manifest in Tc -singularities or Tc -splittings of the k -pairs, whose occurrence can be straightforwardly explained by taking into account the non equivalence of the structural phase diagrams of YBCO, pointed out by electron diffraction, when produced by intercalation of oxygen in the tetragonal T structure or by deintercalation from the orthorhombic OI structure. Tc -singularities are produced in the k ranges for which a superimposition of the phase diagrams occurs, whereas Tc -splitting are pointed out in correspondence of splitted structural regions. The maximum Tc -splitting is observed in proximity of the semiconductor-metal transition with the appearing of superconductivity related to an anti-OIII (OIII*) superstructure in intercalated samples at k =0.30, where the corresponding deintercalated samples are tetragonal and semiconductor. This result confirms that the vanishing of the antiferromagnetic ordering, the emergence of hole doped superconductivity and the symmetry breaking at the T-O transition are nearly coincident phenomena in YBCO. However the related critical oxygen stoichiometry is strictly dependent on the ordering parameter in the Cu(1) plane, i.e. on the formation of extended chains. The OIII* structure, for the first time observed in a systematic way at the T-O transition in intercalated samples, seems to exhibit in analogy with OII and OIII a characteristic Tc .
Rheology of ERF on Various Flow Fields
Authors: Shimada Kunio , Kamiyama Shinichi , Fujita Toyohisa , Iwabuchi Makio , Nishida Hitoshi , Okui Kenichi
Published: July 2002

This paper is concerned with the experimental investigation of electrorheological effect (ER effect) on apparent viscosity and yield stress obtained from hydrodynamic characteristics of electrorheological fluid (ERF) in various flow fields. Our conducting flow fields are made by using rectangular duct, concentric cylindrical pipe, rotating disk and rotating concentric cylinder. The measured parameters of the former two cases are pressure difference at a given volumetric flow rate, and the latters are torque at a given angular velocity. Our using ERF is suspension type. We arrange these data to obtain increment of apparent viscosity and yield stress with and without a supplying D.C. electric field by using integral method of rheology. It is clarified that qualitative values of increment of apparent viscosity and yield stress are different at each flow field. In addition, the quantitative ER effects of shear rate and electric field strength on the increment of apparent viscosity and yield stress are clarified.
RADIATION DAMAGE EFFECTS ON TRANSPORT AND COLOSSAL MAGNETORESISTANCE IN La(1-x)CaxMnO3
Authors: NAUGLE D. G. , RATHNAYAKA K. D. D. , BELEVTSEV B. I.
Published: July 2002

The effects of crystal lattice disorder induced by irradiation of La-Ca-Mn-O films are reviewed. These experiments provide insight into the anomalous transport properties and colossal magnetoresistance (CMR) of these perovskites. Electron irradiation produces only slight lattice damage, about 10-5 displacements per atom (dpa) which would be imperceptible in an ordinary "bad" metal or activated semiconductor but gives large changes in resistance that illustrate the exotic nature of transport in both the metallic and insulating phases of the CMR films. Ion irradiation produces damage ranging from 5×10-3 dpa to 2.4×10-2 dpa which provides a systematic picture of CMR and transport from relatively small lattice disorder to more severe disorder, sufficient to completely supress the metal-insulator (M-I) transition.
AUTOMATIC DETECTION AND TRACKING OF HUMAN HEADS USING AN ACTIVE STEREO VISION SYSTEM
Authors: TANG CHENG-YUAN , CHEN ZEN , HUNG YI-PING
Published: July 2002

A new head tracking algorithm for automatically detecting and tracking human heads in complex backgrounds is proposed. By using an elliptical model for the human head, our Maximum Likelihood (ML) head detector can reliably locate human heads in images having complex backgrounds and is relatively insensitive to illumination and rotation of the human heads. Our head detector consists of two channels: the horizontal and the vertical channels. Each channel is implemented by multiscale template matching. Using a hierarchical structure in implementing our head detector, the execution time for detecting the human heads in a 512×512 image is about 0.02 second in a Sparc 20 workstation (not including the time for image acquisition). Based on the ellipse-based ML head detector, we have developed a head tracking method that can monitor the entrance of a person, detect and track the person's head, and then control the stereo cameras to focus their gaze on this person's head. In this method, the ML head detector and the mutually-supported constraint are used to extract the corresponding ellipses in a stereo image pair. To implement a practical and reliable face detection and tracking system, further verification using facial features, such as eyes, mouth and nostrils, may be essential. The 3D position computed from the centers of the two corresponding ellipses is then used for fixation. An active stereo head has been used to perform the experiments and has demonstrated that the proposed approach is feasible and promising for practical uses.
PATTERN FORMATION AND DYNAMICS IN AN ANNULAR CO2 LASER
Authors: RAMÓN M. L. , BOCCALETTI S. , MEUCCI R. , ALLARIA E.
Published: July 2002

The formation and competition of patterns in an annular CO 2 laser has been experimentally and numerically analyzed. The temporal evolution of the different spatial structures increases its richness and complexity during the coexistence of different patterns. A model based on the Maxwell–Bloch equations, including a symmetry breaking term, provides a numerical interpretation of the main experimental features.
AN OBJECT-ORIENTED APPROACH TO SHADOW GENERATION IN COMPUTER GRAPHICS
Authors: WANG TAEHYUNG , SHEU PHILLIP C.-Y.
Published: July 2002

This paper presents an object-oriented shadow generation algorithm for a large number of convex polyhedra (objects) in a 3-D scene. In the past, the shadow volume binary space partitioning (SVBSP) tree algorithm is known to be efficient in a static environment in which the point light source can be changed. However, if a scene consists of many objects and each object consists of many polygons, the time complexity for generating and traversing an SVBSP tree increases rapidly because the SVBSP tree algorithm only deals with polygons which are components of objects. Furthermore, the SVBSP tree algorithm suffers from polygon-splitting problems resulting in a high cost as the number of polygons increases. Our approach is object-oriented in the sense that an object is used as the basic logical unit instead of polygons. In the preprocessing stage the object ordering for shadow generation is determined for all possible light source positions. At the run time, the shadow detection algorithm is executed, and if necessary, shadow fragments are generated. We also present an approach to retrieving, updating, and displaying a 3-D static or dynamic world which consists of a large number of objects.
A HIERARCHICAL REASONING SYSTEM FOR AUTOMATIC PROGRAM PARALLELIZATION
Authors: LI ZHIYUAN , GU JUNJIE
Published: July 2002

Automatic parallelization of large and complex program regions requires the compiler to reason about complex semantic information. This paper describes a hierarchical reasoning system implemented within the Panorama parallelizing compiler. This reasoning system intelligently and efficiently extracts useful semantic information in the form of first-order predicates from program statements. It uses a hierarchical structure to represent the predicates, which enables fast determination of their truth in common cases. A hierarchical value graph facilitates rule-based, demand-driven retrieval of useful predicates.
MAINTAINING SPATIAL CONSTRAINTS USING A DIMENSION GRAPH APPROACH
Authors: LIU XUAN , SHEKHAR SHASHI , CHAWLA SANJAY
Published: July 2002

Efficient algorithms for checking consistency of a set of spatial constraints among spatiotemporal objects are crucial for many practical application systems needing real-time response. This paper is focused on the consistency for directional spatial constraints in a two-dimensional Euclidean space, which is critical in application domains such as geographic information systems, battlefield visualization, transportation, etc. We propose a dimension graph representation to maintain the Euclidean spatial constraints among 2D objects (points, intervals, regions). The basic idea is to project the spatial constraints on both X and Y dimensions, and then to construct a dimension graph on each dimension. The dimension graph representation transforms the problem of consistency checking into the problem of graph cycle detection. Consistency checking for conjunctive constraints can then be achieved in linear time complexity. This approach is much more efficient than competing approaches when there are few disjunctions in the spatial constraints, which are often true in above applications. We also demonstrate that the proposed algorithm can guarantee global consistency.
COMMENSURABILITY CLASSES OF ARITHMETIC LINK COMPLEMENTS
Authors: BAKER MARK D.
Published: July 2002

In this paper, we exhibit three new commensurability classes of arithmetic link complements, bringing the known total to seventeen.
PERSISTENT LAMINATIONS FROM SEIFERT SURFACES
Authors: BRITTENHAM MARK
Published: July 2002

We show how an incompressible Seifert surface F for a knot K in S3 can be used to create an essential lamination ℒF in the complement of each of an infinite class of knots associated to F. This lamination is persistent for these knots; it remains essential under all non-trivial Dehn fillings of the knot complement. This implies a very strong form of Property P for each of these knots.
A REVIEW OF TECHNIQUES FOR THE ESTIMATION OF THE TERM STRUCTURE
Authors: MARANGIO LIVIO , MASSIMO MASSIMO , RAMPONI ALESSANDRO
Published: July 2002

A number of techniques have been proposed for estimating the term structure, yet solid theoretical foundations and a comparative assessment of the results produced by these techniques are not available. In the present paper we prove, within a well defined mathematical setting, how the existence of discount factors is possible only if the condition of absence of static arbitrage is fulfilled. Besides that we report the results of an extensive set of tests whose scope is to show how the most widely used approaches in this field behave on both real and synthetic data.
DIRECTED EMBEDDINGS AND THE SIMPLIFICATION OF SINGULARITIES
Authors: SPRING DAVID
Published: July 2002

A theory of simplification of singularities of maps is developed, based on Gromov's convex integration theory. In particular, subject to mild bundle hypotheses, up to a C0-small smooth ambient isotopy of embeddings, the singularities induced by the restriction of a submersion to a smoothly embedded closed submanifold are simplified to be only fold i.e. Morse singularities.