bluuebunny/crossref_metadata_2025 huggingface dataset:
Demonstration of the healthy worker survivor effect in a cohort of workers in the construction industry
Authors: Siebert U , Rothenbacher D , Daniel U , Brenner H
Published: July 2002

OBJECTIVES

To assess the potential of a healthy worker survivor effect due to differential occupational mobility in a cohort of construction workers.

METHODS

A cohort of 10 809 male employees in the German construction industry aged 15–64 years was followed up for occupational mobility, early retirement due to permanent disability, and total mortality from 1986 to 1994. Using the Cox's proportional hazards model of relative rates (RRs) with 95% confidence intervals (95% CIs) of occupational mobility, early retirement and total mortality were estimated according to medical diagnoses at baseline after adjustment for various covariates.

RESULTS

During follow up, 2472 subjects changed employment, 359 employees were granted a disability pension for health reasons and 188 subjects died. A wide range of chronic diseases was associated with increased rates of early retirement and total mortality but not occupational mobility. However, a healthy worker survivor effect was identified related to disorders of the back and spine (ninth revision of the international classification of diseases, ICD-9, code 720-4), a common predictor of both occupational mobility (RR 1.17, 95% CI 1.04 to 1.32) and early retirement (RR 1.50, 95% CI 1.20 to 1.88). In total, there were about as many events of occupational changes (n = 41) as events of early retirement due to permanent disability (n = 39) significantly attributable to disorders of the back and spine. Differential occupational mobility preceded differential early retirement due to permanent disability by more than one decade.

CONCLUSIONS

These findings show the need to consider a healthy worker survivor effect due to occupational mobility in occupational epidemiological research. Furthermore these results underline the necessity of further health promotion targeting work related conditions in the construction industry.
Effects of drop out in a longitudinal study of musculoskeletal disorders
Authors: Bildt C , Alfredsson L , Punnett L , Theobald H , Torgén M , Wikman A
Published: July 2002

OBJECTIVES

The drop out rates in different longitudinal studies of musculoskeletal disorders range between 7% and 57%, and little is known about the characteristics of the subjects who dropped out. The aim was to analyse various consequences of drop out in a longitudinal study of musculoskeletal disorders and occupational risk factors during 1969–97.

METHOD

Data about occupational conditions and health in 1969 and in 1993 were analysed. Differences between those who participated throughout (participants) and drop out subjects in these analyses formed the basis for recalculations of earlier reported analyses of associations between occupational conditions and low back pain. In the recalculation the data were weighted to compensate for the differences.

RESULTS

More female and male drop out subjects than participants in 1993 had monotonous work, fewer women and more male drop out subjects had heavy lifting in 1969. In 1997, more female and male drop out subjects had had heavy lifting and low stimulation at work in 1993. At both occasions, there were differences between the drop out subjects and participants in occurrence of musculoskeletal disorders. The weighted analyses resulted in changes in risk ratio of 0.1–0.2.

CONCLUSIONS

Differences in occupational conditions and health among participants and drop out subjects in a longitudinal study of musculoskeletal disorders and occupational risk factors during 1969–97 did not markedly influence the risk ratios.
Environmental tobacco smoke and lung function in employees who never smoked: the Scottish MONICA study
Authors: Chen R , Tunstall-Pedoe H , Tavendale R
Published: July 2002

OBJECTIVES

To investigate the relation between lung function in employees and exposure to environmental tobacco smoke (ETS) at work and elsewhere.

METHODS

Never smokers in employment (301) were identified from the fourth Scottish MONICA survey. They completed a self administered health record, which included details of exposure to ETS, and attended a survey clinic for physical and lung function measurements, and for venepuncture for estimation of serum cotinine. Differences in lung function in groups exposed to ETS were tested by analysis of variance (ANOVA), the exposure-response relation by a linear regression model, and a case-control analysis undertaken with a logistic regression model.

RESULTS

Both men and women showed effects on forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) from exposure to ETS—higher exposure going with poorer lung function. This was found at work, and in total exposure estimated from ETS at work, at home, and at other places. Linear regression showed an exposure-response relation, significant for ETS at work, total exposure, and exposure time/day, but not at home or elsewhere. Compared with those not exposed to ETS at work, those who were exposed a lot had a 254 ml (95% confidence interval (95% CI) 84 to 420) reduction in FEV1, and a 273 ml (60 to 480) reduction in FVC after adjusting for confounders. Although lung function was not significantly associated with serum cotinine in all the data, a significant inverse relation between cotinine concentration and FVC occurred in men who had had blood collected in the morning. Case-control analysis also showed a significant exposure-response relation between ETS, mainly at work, and lung function. A higher exposure measured both by self report and serum cotinine went with lower lung function.

CONCLUSION

The exposure-response relation shows a reduction in pulmonary function of workers associated with passive smoking, mainly at work. These findings endorse current policies of strictly limiting smoking in shared areas, particularly working environments.
Use of a computerised maternity information system to improve clinical effectiveness: thromboprophylaxis at caesarean section
Authors: Taylor Graham M , McKenzie Clare A , Mires Gary J
Published: July 2002

An audit of the introduction of a protocol for thromboprophylaxis at caesarean section revealed over treatment of low risk women and the under treatment of high risk women. A routine computer generated risk assessment profile was introduced as part of a maternity information system. Reaudit showed a significant improvement in adherence to the thromboprophylaxis protocol in all risk groups.
Extensive psoriasis induced by interferon alfa treatment for chronic hepatitis C
Authors: Taylor C , Burns D A , Wiselka M J
Published: July 2002

A 47 year old man with chronic hepatitis C was treated with interferon alfa, 3 million units three times a week, and developed widespread plaque psoriasis within weeks of starting interferon therapy. There was no previous history of psoriasis. The psoriasis was characterised by extensive nail involvement and plaques at the interferon injection sites. The patient relapsed after a total of 12 months of interferon and was subsequently treated with interferon and tribavirin (ribavirin) with recurrence of the psoriasis.
Can media advocacy influence newspaper coverage of tobacco: measuring the effectiveness of the American stop smoking intervention study's (ASSIST) media advocacy strategies
Authors: Stillman Frances A , Cronin Kathleen A , Evans W Douglas , Ulasevich Alec
Published: July 2002

OBJECTIVE

To compare the rate and slant of local tobacco control print media coverage in ASSIST (American stop smoking intervention study) states as compared with non-ASSIST states.

METHODS

Local tobacco control policy articles, editorials, and letters to the editors published from 1994 to 1998 clipped from all daily local newspapers in the USA were analysed (n = 95 911). The main hypothesis tested for the existence of an interaction between ASSIST intervention and time. This interaction would represent a change in the difference between ASSIST and non-ASSIST states over the course of the intervention.

RESULTS

No evidence of an ASSIST–year interaction was found. However, a main effect for ASSIST was significant for the percentage of articles with the model predicting higher rates of articles for ASSIST states. Similarly the rate of letters to the editor expressing protobacco control views was higher in ASSIST states than non-ASSIST states. No main effects or interactions were found for analyses of percentage of protobacco control editorials. Models controlled for a measure of preintervention tobacco control conditions at baseline.

CONCLUSIONS

The presence of an ASSIST main effect should be interpreted with caution because of the quasi-experimental design and the lack of information on article rates before the ASSIST intervention. Nonetheless, these preliminary findings suggest some possible effects of the media advocacy activities of ASSIST when controlling for differences in states' initial tobacco control conditions.
Hungry for tobacco: an analysis of the economic impact of tobacco consumption on the poor in Bangladesh
Authors: Efroymson Debra , Ahmed Saifuddin , Townsend Joy , Alam Syed Mahbubul , Dey Amit Ranjan , Saha Ranjit , Dhar Biplob , Sujon Aminul Islam , Ahmed Kayum Uddin , Rahman Oliur
Published: July 2002

OBJECTIVE

To investigate the extent of tobacco expenditures in Bangladesh and to compare those costs with potential investment in food and other essential items.

DESIGN

Review of available statistics and calculations based thereon.

RESULTS

Expenditure on tobacco, particularly cigarettes, represents a major burden for impoverished Bangladeshis. The poorest (household income of less than $24/month) are twice as likely to smoke as the wealthiest (household income of more than $118/month). Average male cigarette smokers spend more than twice as much on cigarettes as per capita expenditure on clothing, housing, health and education combined. The typical poor smoker could easily add over 500 calories to the diet of one or two children with his or her daily tobacco expenditure. An estimated 10.5 million people currently malnourished could have an adequate diet if money on tobacco were spent on food instead. The lives of 350 children could be saved each day.

CONCLUSION

Tobacco expenditures exacerbate the effects of poverty and cause significant deterioration in living standards among the poor. This aspect of tobacco use has been largely neglected by those working in poverty and tobacco control. Strong tobacco control measures could have immediate impact on the health of the poor by decreasing tobacco expenditures and thus significantly increasing the resources of the poor. Addressing the issue of tobacco and poverty together could make tobacco control a higher priority for poor countries.
Intermittent and daily smokers: two different socioeconomic patterns, and diverging influence of social participation
Authors: Lindström Martin , Östergren Per-Olof
Published: July 2002

OBJECTIVE

To investigate socioeconomic differences in intermittent and daily smoking, and to assess the association between social participation and these two smoking behaviours.

DESIGN/SETTING/PARTICIPANTS/MEASUREMENTS

A population of 11 837 individuals interviewed in 1992-94, aged 45–64 years, was investigated in this cross sectional study. A multivariate logistic regression model was used to assess socioeconomic differences in daily and intermittent smoking, adjusting for age, country of origin, previous/current diseases, and marital status. Finally, social participation as a measure of social capital was introduced in the multivariate model.

RESULTS

When unskilled manual workers were compared to high level non-manual employees, odds ratios of 2.3 (95% confidence interval (CI) 1.7 to 3.0) for men and 1.9 (95% CI 1.4 to 2.5) for women were found in regard to daily smoking, but odd ratios of only 0.7 (95% CI 0.4 to 1.2) for men and 1.3 (95% CI 0.7 to 2.4) for women were found in regard to intermittent smoking. A decrease in the daily smoking odds ratios was found when social participation was introduced in the model, while the odds ratios regarding intermittent smoking were unaffected.

CONCLUSIONS

There were no socioeconomic differences in intermittent smoking and no association with social participation, a result that contrasts sharply with the patterns of daily smoking. These findings have important implications for the discussion concerning social capital and preventive measures.
Cigarette acquisition and proof of age among US high school students who smoke
Authors: Jones S Everett , Sharp D J , Husten C G , Crossett L S
Published: July 2002

Objective: To determine how US high school students who are under 18 years of age and who smoke obtain their cigarettes and whether they are asked for proof of age.

Design and setting: Data from the Centers for Disease Control and Prevention's 1995, 1997, and 1999 national Youth Risk Behavior Surveys which employed national probability samples of students in grades 9–12 (ages 14–18 years).

Main outcome measures: Associations of usual source of cigarettes and request for proof of age with variables such as sex, race/ethnicity, grade, and frequency of smoking.

Results: In 1999, among current smokers under age 18 years, 23.5% (95% confidence interval (CI), −4.5% to +4.5%) usually purchased their cigarettes in a store; among these students, 69.6% (95% CI −5.7% to +5.7%) were not asked to show proof of age. As days of past month smoking increased, reliance on buying cigarettes in a store (p < 0.001) and giving someone else money to buy cigarettes (p < 0.001) increased, and usually borrowing cigarettes decreased (p < 0.001). From 1995 to 1999, relying on store purchases significantly decreased (from 38.7% (95% CI −4.6% to + 4.6%) to 23.5% (95% CI −4.5% to +4.5%)); usually giving someone else money to buy cigarettes significantly increased (from 15.8% (95% CI −3.6% to +3.6%) to 29.9% (95% CI −4.5% to + 4.5%)).

Conclusions: Stricter enforcement of tobacco access laws is needed to support other community and school efforts to reduce tobacco use among youth. Furthermore, effective interventions to reduce non-commercial sources of tobacco, including social, need to be developed and implemented.
Effects of cigarette tax on cigarette consumption and the Chinese economy
Authors: Hu T W , Mao Z
Published: July 2002

Objectives:To analyse a policy dilemma in China on public health versus the tobacco economy through additional cigarette tax.

Methods:Using published statistics from 1980 through 1997 to estimate the impact of tobacco production and consumption on government revenue and the entire economy. These estimates relied on the results of estimated price elasticities of the demand for cigarettes in China.

Results:Given the estimated price elasticities (−0.54), by introducing an additional 10% increase in cigarette tax per pack (from the current 40% to 50% tax rate), the central government tax revenue would twice exceed total losses in industry revenue, tobacco farmers' income, and local tax revenue. In addition, between 1.44 and 2.16 million lives would be saved by this tax increase.

Conclusions:Additional taxation on cigarettes in China would be a desirable public policy for the Chinese government to consider.
Was there significant tax evasion after the 1999 50 cent per pack cigarette tax increase in California?
Authors: Emery S , White M M , Gilpin E A , Pierce J P
Published: July 2002

Objectives:Several states, including California, have implemented large cigarette excise tax increases, which may encourage smokers to purchase their cigarettes in other lower taxed states, or from other lower or non-taxed sources. Such tax evasion thwarts tobacco control objectives and may cost the state substantial tax revenues. Thus, this study investigates the extent of tax evasion in the 6–12 months after the implementation of California's $0.50/pack excise tax increase.

Design and setting:Retrospective data analysis from the 1999 California Tobacco Surveys (CTS), a random digit dialled telephone survey of California households.

Main outcome measures:Sources of cigarettes, average daily cigarette consumption, and reported price paid.

Results:Very few (5.1 (0.7)% (±95% confidence limits)) of California smokers avoided the excise tax by usually purchasing cigarettes from non- or lower taxed sources, such as out-of-state outlets, military commissaries, or the internet. The vast majority of smokers purchased their cigarettes from the most convenient and expensive sources: convenience stores/gas (petrol) stations (45.0 (1.9)%), liquor/drug stores (16.4 (1.6)%), and supermarkets (8.8 (1.2)%).

Conclusions:Despite the potential savings, tax evasion by individual smokers does not appear to pose a serious threat to California's excise tax revenues or its tobacco control objectives.
My pack is cuter than your pack
Authors: Wakefield M , Letcher T
Published: July 2002

Faced with bans on advertising, the tobacco companies are looking to new, more subtle ways of maintaining their brands' profile in the public eye
Arbuscular mycorrhizal fungi respond to increasing plant diversity
Authors: Burrows Rhoda L , Pfleger Francis L
Published: July 2002

The effect of plant diversity (1, 2, 8, or 16 species) on arbuscular mycorrhizal fungi (AMF) was assessed at the Cedar Creek Long-Term Ecological Research site at East Bethel, Minnesota, from 1997 to 1999. At each of the five samplings, AMF in 16-species plots produced from 30 to 150% more spores and from 40 to 70% greater spore volumes than AMF in one-species plots. Regressions of spore numbers and volumes with percent plant cover, plant diversity, and soil NO3 as independent variables suggest that midsummer plot soil NO3 was the best single predictor of AMF spore production in these plots. Plant diversity influenced spore volume in four samplings and spore numbers in the first three samplings. Plant cover was predictive of spore volume throughout the experiment but of spore number only in the first year. Sporulation by larger-spored AMF species (Gigaspora spp. and Scutellospora spp.) increased significantly with increasing plant diversity, while sporulation of the smaller-spored species varied in response to host diversity. Spore numbers of several AMF species were consistently negatively correlated and none positively correlated with midseason soil NO3 concentrations, demonstrating the adaptation of these AMF species to nitrogen-limited conditions.Key words: mycorrhiza, community, grassland, sporulation, nitrogen, specificity.
Species richness, abundance, and composition of hypogeous and epigeous ectomycorrhizal fungal sporocarps in young, rotation-age, and old-growth stands of Douglas-fir (Pseudotsuga menziesii) in the Cascade Range of Oregon, U.S.A.
Authors: Smith J E , Molina R , Huso M MP , Luoma D L , McKay D , Castellano M A , Lebel T , Valachovic Y
Published: July 2002

Knowledge of the community structure of ectomycorrhizal fungi among successional forest age-classes is critical for conserving fungal species diversity. Hypogeous and epigeous sporocarps were collected from three replicate stands in each of three forest age-classes (young, rotation-age, and old-growth) of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) dominated stands with mesic plant association groups. Over four fall and three spring seasons, 48 hypogeous and 215 epigeous species or species groups were collected from sample areas of 6300 and 43 700 m2, respectively. Cumulative richness of hypogeous and epigeous species was similar among age-classes but differed between seasons. Thirty-six percent of the species were unique to an age-class: 50 species to old-growth, 19 to rotation-age, and 25 to young stands. Seventeen species (eight hypogeous and nine epigeous) accounted for 79% of the total sporocarp biomass; two hypogeous species, Gautieria monticola Harkn., and Hysterangium crassirhachis Zeller and Dodge, accounted for 41%. Average sporocarp biomass in young and rotation-age stands compared with old-growth stands was about three times greater for hypogeous sporocarps and six times greater for epigeous sporocarps. Average hypogeous sporocarp biomass was about 2.4 times greater in spring compared with fall and for epigeous sporocarps about 146 times greater in fall compared with spring. Results demonstrated differences in ectomycorrhizal fungal sporocarp abundance and species composition among successional forest age-classes.Key words: ectomycorrhizal fungi, sporocarp production, forest succession, Pseudotsuga menziesii, Tsuga heterophylla zone, biodiversity.
Origin of vertical shafts in bedrock along the Eramosa River valley near Guelph, southern Ontario
Authors: Kunert Micheal , Coniglio Mario
Published: July 2002

Numerous vertical to subvertical, cylindrical shafts occur in the rugged exposures of the Middle Silurian Amabel Formation bedrock along the Eramosa River, approximately 10 km northeast of Guelph. These shafts vary from < 1 m to 10 m in diameter, with depths as great as 12 m. They can occur as isolated depressions but more commonly are clustered closely together, and many coalesce to form sinuous bedrock walls. These depressions may contain soil, fine sediment, rubble from the surrounding dolomite bedrock, and rounded clasts of Precambrian basement lithologies. Till is conspicuously absent. These shafts occur in close proximity to cavernous pores that were formed during pre-Wisconsinan to Early Wisconsinan time, suggesting a possible karstic origin. The cylindrical shafts, however, with their greater midpoint diameters, sculpted interiors, and inclined axes, and their lack of vertical flutes and till, are more likely to have originated from glaciofluvial discharge at the end of the Late Wisconsinan. The development of these shafts may have been assisted by cavitation, which enhanced the erosional capacity of sediment-laden meltwaters.
Chromosomal and allelic variation inDrosophila americana: selective maintenance of a chromosomal cline
Authors: McAllister Bryant F
Published: July 2002

Geographically structured genetic variation, as represented by clines and hybrid zones, offers unique opportunities to study adaptation and speciation in natural populations. A hybrid zone has been reported between Drosophila americana americana and Drosophila americana texana, two taxa that are distinguished solely by the arrangement of their X and 4th chromosomes. In this study, samples of D. americana were collected along a latitudinal transect across the inferred hybrid zone, and the frequency of the alternative chromosomal arrangements is reported. These data illustrate that the alternative chromosomal arrangements are distributed along a shallow cline over a broad geographic region, and that the frequency of the arrangements is tightly correlated with latitude. Allelic variants at 13 RFLP loci in three genes on chromosome 4 exhibit no evidence of association with the cline. Presence of a cline for the chromosomal arrangements, as well as a general absence of geographic structure for variation at these genes, is interpreted as evidence that natural selection is responsible for the maintenance of this chromosomal cline. Furthermore, these results demonstrate that taxonomic subdivision of D. americana is unwarranted, because it exists as a cohesive species that is segregating a chromosomal fusion.Key words: chromosomal evolution, Robertsonian fusion, hybrid zone, cline, geographic variation, natural selection.
Mechanical and bond properties of new generation of carbon fibre reinforced polymer reinforcing bars for concrete structures
Authors: Benmokrane Brahim , Zhang Burong , Laoubi Kader , Tighiouart Brahim , Lord Isabelle
Published: July 2002

This paper presents laboratory test results on the mechanical properties and bond strength of new generation of carbon fibre reinforced polymer (CFRP) reinforcing bars used as nonprestressed reinforcement for concrete structures. Two types of CFRP reinforcing bars, namely, 9-mm-diameter CFRP ribbed bars and 9.5-mm-diameter CFRP sand-coated bars, were investigated. Tensile tests and pullout bond tests were conducted to evaluate the tensile properties and bond strength of the CFRP bars in comparison with that of the steel bar. Experimental results showed that the tensile stress-strain curves of the CFRP bars were linear up to failure. The ultimate tensile strength of the two types of CFRP bars was at least 1500 MPa, three times that of steel bars. The modulus of elasticity of two types of the CFRP bars was 128145 GPa, about 6575% that of steel. Furthermore, both types of the CFRP bars exhibited almost the same bond strength to concrete similar to steel bars. The minimum bond development length for the two types of CFRP bars seemed to be equal to about 20db for the sand-coated bars and 30db for the ribbed bars.Key words: fibre reinforced polymer (FRP), carbon FRP (CFRP), bar, mechanical properties, tensile strength, embedded length, pullout, bond strength, concrete structures.
Application de la scanographie à l'étude de la densité des sédiments et à la caractérisation des structures sédimentaires : exemple des sédiments déposés dans la rivière Saguenay (Québec, Canada) après la crue de juillet 1996
Authors: Crémer Jean-François , Long Bernard , Desrosiers Gaston , Montety Laure de , Locat Jacques
Published: July 2002

Following the flood of July 1996, a significant quantity of sediment, coming from the catchment areas contiguous to the Saguenay fjord, was discharged in the Baie des Ha! Ha! and the North Arm. To characterize the mode of deposit and the potential for remobilization of these deposits, a series of cores was taken in the fjord using a box corer and a gravity corer during the summers of 1997 and 1998. These cores have been analyzed by the axial tomodensitometer at the Regional Hospital Center of Rimouski. The use of the tomodensitometer in geology allows a nondestructive study of the sample and a qualitative and quantitative evaluation of the density of the sediments, their mode of deposition, and their compaction. The study of the upper 45 cm of sediments shows the presence, in the uppermost layer, of several facies type characteristics of a gravity deposit. This layer rests on an erosional unconformity cut into the surface of the older deposits, themselves of gravity type. One year after the flood, no trace of reworking could be detected in the upper part of the cores. Nevertheless, cores taken in the summer of 1998 show a significant reworking of the superficial sediments in direct relation with bioturbation. No reworking of hydrodynamic origin was observed.Key words: scanography, flood, turbidity currents, sedimentary structures, compaction, bioturbation.
Origin, development, and dynamics of coastal temperate conifer rainforests of southern Vancouver Island, Canada
Authors: Brown K J , Hebda R J
Published: July 2002

Pollen and charcoal from East Sooke Fen, Pixie Lake, and Whyac Lake were used to reconstruct the post glacial vegetation, climate, and fire-disturbance history across a precipitation gradient on southern Vancouver Island, British Columbia. An open Pinus woodland covered the landscape in the early late-glacial interval. Fires were absent under a cool and dry climate. Closed mixed conifer forests of Pinus, Picea, Abies, Tsuga heterophylla (Raf.) Sarg., and Tsuga mertensiana (Bong.) Carrière replaced the Pinus biogeochron in the late late-glacial interval. Fires became more common even though climate was cool and moist. Open Pseudotsuga menziesii (Mirb.) Franco forests expanded westward during the warm dry early Holocene, though closed Picea and Tsuga heterophylla forests grew in the wettest part of the area at Whyac Lake. Modern precipitation gradients likely originated at this time. Fires occurred in forested ecosystems, although East Sooke Fen at the driest end of the gradient experienced less fire. The middle and late Holocene was characterized by increasing precipitation and decreasing temperature, respectively. Quercus garryana Dougl. stands spread westward during the mid-Holocene. Extant closed Tsuga heterophylla and Cupressaceae (Thuja plicata Donn. ex D. Don) forests arose in the wetter part of the gradient, whereas Pseudotsuga forests occupied drier eastern areas. During this interval, fires were rare in wet western regions but apparently more common in dry eastern regions.
Fast-start swimming performance and reduction in lateral plate number in threespine stickleback
Authors: Bergstrom C A
Published: July 2002

Threespine stickleback (Gasterosteus aculeatus) have colonized freshwater habitats in circumboreal coastal regions, resulting in populations with variable but generally reduced lateral plate numbers compared with marine ancestors. Several abiotic and ecological factors associated with variation in lateral plate number among freshwater populations of G. aculeatus have been found, including large-scale climatic effects, variation in water-flow rates and levels of dissolved calcium, and the presence or absence of predatory fish. In addition, it has been proposed that plate reduction might be an adaptation for evading predator pursuit that enhances fast-start performance. If this hypothesis is correct, one would predict that fast-start performance would improve as lateral plate numbers decrease. I tested this prediction by comparing fast-start performance among stickleback with different numbers of lateral plates within two freshwater populations. Fast-starts of individual stickleback were video-recorded at 60 Hz and maximum velocity, maximum acceleration, displacement, and body curvature were calculated for each fish. Lateral plate number was significantly negatively correlated with velocity and displacement but not with acceleration or curvature. These results suggest that reduction in lateral plate number has the potential to be advantageous in some predation regimes because of its association with enhanced fast-start performance.
STRONG DYNAMICAL LOCALIZATION FOR THE ALMOST MATHIEU MODEL
Authors: GERMINET FRANÇOIS , JITOMIRSKAYA SVETLANA
Published: July 2002

In this note we prove Strong Dynamical Localization for the almost Mathieu operator Hθ,λ,ω=-Δ+ λ cos (2π(θ + xω)) for all λ>2 and Diophantine frequencies ω. This improves the previous known result [22, 13] which established Dynamical Localization for a.e. θ and for λ≥15.
BRAID STATISTICS IN LOCAL QUANTUM THEORY
Authors: FRÖHLICH J. , GABBIANI F.
Published: July 2002

We present details of a mathematical theory of superselection sectors and their statistics in local quantum theory over (two- and) three-dimensional space-time. The framework for our analysis is algebraic quantum field theory. Statistics of superselection sectors in three-dimensional local quantum theory with charges not localizable in bounded space-time regions and in two-dimensional chiral theories is described in terms of unitary representations of the braid groups generated by certain Yang-Baxter matrices. We describe the beginnings of a systematic classification of those representations. Our analysis makes contact with the classification theory of subfactors initiated by Jones. We prove a general theorem on the connection between spin and statistics in theories with braid statistics. We also show that every theory with braid statistics gives rise to a “Verlinde algebra”. It determines a projective representation of SL(2, ℤ) and, presumably, of the mapping class group of any Riemann surface, even if the theory does not display conformal symmetry.
GROUND STATE RESONANCES OF A HYDROGEN ATOM IN AN INTENSE MAGNETIC FIELD
Authors: FROESE RICHARD , WAXLER ROGER
Published: July 2002

We consider a hydrogen atom in a constant and very large magnetic field. For bounded angular momentum about the direction of the magnetic field we consider resonances in the sense of dilation analyticity. We find a class of resonances corresponding to quasi-stationary states which behave in a certain sense like ground states. The position of these resonances in the complex plane is estimated. Further it is shown that under the time evolution generated by the Hamiltonian for this system these quasi-stationary states exhibit exponential decay in time.
8-Vertex Correlation Functions and Twist Covariance of q-KZ Equation
Authors: Frønsdal C. , Galindo A.
Published: July 2002

We study the vertex operators Φ(z) associated with standard quantum groups. The element Z=RR t is a "Casimir operator" for quantized Kac–Moody algebras and the quantum Knizhnik–Zamolodchikov (q-KZ) equation is interpreted as the statement :ZΦ(z):=Φ(z). We study the covariance of the q-KZ equation under twisting, first within the category of Hopf algebras, and then in the wider context of quasi Hopf algebras. We obtain the intertwining operators associated with the elliptic R-matrix and calculate the two-point correlation function for the eight-vertex model.
THE ONSET OF MACKEY–GLASS LEUKEMIA AT THE EDGE OF CHAOS
Authors: DE MENEZES M. ARGOLLO , DOS SANTOS R. M. ZORZENON
Published: July 2002

In this paper, we revisit the Mackey–Glass model for blood-forming process which was proposed to describe the spontaneous fluctuations of the blood cell counts in normal individuals and the first stage of chronic myelocytic (or granylocytic) leukemia (CML). We obtain the bifurcation diagram as a function of the time delay parameter and show that the onset of leukemia is related to instabilities associated to the presence of periodic windows in the midst of a chaotic regime. We also introduce a very simple modification in the death rate parameter in order to simulate the accumulation of cells and the progressive increase of the minima counts experimentally observed in the final stage of the disease in CML patients. The bifurcation diagram as a function of the death rate parameter is also obtained and we discuss the effects of treatments like leukapheresis.
REGULATION EFFECTS ON MARKET WITH BAK–SNEPPEN MODEL IN HIGH DIMENSIONS
Authors: YAMANO TAKUYA
Published: July 2002

We present the effect of regulations on self-organized market by using biological model of Bak–Sneppen in higher dimensions. This study extends the idea of Cuniberti et al. The higher-dimensional description of the market receives less effect of regulation than that of lower one.
POSITONIC SOLUTIONS OF A VARIABLE-COEFFICIENT KdV EQUATION IN FLUID DYNAMICS AND PLASMA PHYSICS
Authors: GAO YI-TIAN , TIAN BO
Published: July 2002

Positons are a new concept in nonlinear sciences. In this paper, we report some positonic, exact analytic solutions for a variable-coefficient Korteweg-de Vries (KdV) equation arising from fluid dynamics and plasma physics.
Rasayanas: Evidence for the Concept of Prevention of Diseases
Authors: Vayalil Praveen K. , Kuttan Girija , Kuttan Ramadasan
Published: July 2002

Rasayanas are non-toxic Ayurvedic complex herbal preparations or individual herbs used to rejuvenate or attain the complete potential of an individual in order to prevent diseases and degenerative changes that leads to disease. The present paper reviews various activities of Rasayanas to support the above concept, its role as a prophylactic medication and significance in the prevention of diseases in both healthy as well as diseased individuals. The emerging data suggest that the possible mechanisms may be by immunostimulation, quenching free radicals, enhancing cellular detoxification mechanisms, repair damaged non-proliferating cells, inducing cell proliferation and self-renewal of damaged proliferating tissues, and replenishing them by eliminating damaged or mutated cells with fresh cells.
POWER CORRECTIONS TO THE PION–PHOTON TRANSITION FORM FACTOR Fπγ(Q2)
Authors: AGAEV SHAHIN S. , MUKHTAROV ABDULLA I.
Published: July 2002

Power-suppressed corrections ~(1/Q2)p, p = 1,2… to the electromagnetic transition form factor Q2Fπγ(Q2) are estimated using the running coupling constant method. Within this method the renormalization scale in the QCD expression for Fπγ(Q2) is taken to be equal to [Formula: see text] (or to [Formula: see text]) and computation of the form factor with running coupling [Formula: see text] is carried out. In calculations the pion asymptotic and model distribution amplitudes (DAs), as well as DAs found in the context of the "naive non-Abelianization" approximation are employed. Comparisons are made with frozen coupling constant approximation results and with the experimental data.
THE EXACT RENORMALIZATION GROUP IN ASTROPHYSICS
Authors: GAITE JOSÉ
Published: July 2002

The coarse-graining operation in hydrodynamics is equivalent to a change of scale which can be formalized as a renormalization group transformation. In particular, its application to the probability distribution of a self-gravitating fluid yields an "exact renormalization group equation" of Fokker-Planck type. Since the time evolution of that distribution can also be described by a Fokker-Planck equation, we propose a connection between both equations, that is, a connection between scale and time evolution. We finally remark on the essentially non-perturbative nature of astrophysical problems, which suggests that the exact renormalization group is the adequate tool for them.
SCHEME INDEPENDENCE AS AN INHERENT REDUNDANCY IN QUANTUM FIELD THEORY
Authors: LATORRE JOSÉ I. , MORRIS TIM R.
Published: July 2002

The path integral formulation of Quantum Field Theory implies an infinite set of local, Schwinger-Dyson-like relation. Exact renormalization group equations can be cast as a particular instance of these relations. Furthermore, exact scheme independence is turned into a vector field transformation of the kernel of the exact renormalization group equation under field redefinitions.
EXACT RENORMALIZATION GROUP IN ALGEBRAIC NONCOVARIANT GAUGES
Authors: SIMIONATO M.
Published: July 2002

I study a class of Wilsonian formulations of non-Abelian gauge theories in algebraic noncovariant gauges where the Wilsonian infrared cutoff Λ is inserted as a mass term for the propagating fields. In this way the Ward-Takahashi identities are preserved to all scales. Nevertheless the BRS-invariance in broken and the theory is gauge-dependent and unphysical at Λ≠ 0. Then I discuss the infrared limit Λ→0. I show that the singularities of the axial gauge choice are avoided in planar gauge and in light-cone gauge. Finally the rectangular Wilson loop of size 2L×2T is evaluated at lowest order in perturbation theory and a noncommutativity between the limits Λ→0 and T→∞ is pointed out.
SOLITONIC BRANE WORLD WITH COMPLETELY LOCALIZED (SUPER)GRAVITY
Authors: IGLESIAS ALBERTO , KAKUSHADZE ZURAB
Published: July 2002

We construct a solitonic three-brane solution in the five-dimensional Einstein–Hilbert–Gauss–Bonnet theory. This solitonic brane is δ-function-like, and has the property that gravity is completely localized on the brane. That is, there are no propagating degrees of freedom in the bulk, while on the brane we have purely four-dimensional Einstein gravity. Thus, albeit the classical background is five-dimensional, the quantum theory (perturbatively) is four-dimensional. Our solution can be embedded in the supergravity context, where we have completely localized supergravity on the corresponding solitonic brane, which is a BPS object preserving 1/2 of the original supersymmetries. By including a scalar field, we also construct a smooth domain wall solution, which in a certain limit reduces to the δ-function-like solitonic brane solution (this is possible for the latter breaks diffeomorphisms only spontaneously). We then show that in the smooth domain wall background the only normalizable mode is the four-dimensional graviton zero mode, while all the other (including massive Kaluza–Klein) modes are not even plane-wave normalizable. Finally, we observe that in compactifications of Type IIB on five-dimensional Einstein manifolds other than a five-sphere the corresponding dual gauge theories on D3-branes are not conformal in the ultraviolet, and at the quantum level we expect the Einstein–Hilbert term to be generated in their world volumes. We conjecture that in full string theory on Type IIB side this is due to higher curvature terms, which cannot be ignored in such backgrounds. A stronger version of this conjecture also states that (at least in some cases) in such backgrounds D3-branes are solitonic objects with completely localized (super)gravity in their world volumes.
ROUGHENING/WETTING TRANSITION IN A GROWTH MODEL WITH ADSORPTION AND DESORPTION
Authors: RUIZ FEDERICO M. , ALBANO EZEQUIEL V.
Published: July 2002

A one-dimensional growth model where particles are adsorbed with probability P A and desorbed with probability P D = exp (-nE/k B T), where n is the number of nearest-neighbors (NN), E is the NN interaction energy, k B is the Boltzmann constant and T is the temperature, is presented and studied by means of numerical simulations. It is shown that, at a given temperature, there is a critical adsorption probability [Formula: see text], such as the model displays a roughening/wetting transition between a smooth and a rough interface for [Formula: see text] and [Formula: see text], respectively. The former phase is bounded to the substratum while the later propagates at constant velocity away from the substratum. The roughening phase diagram, i.e. a critical curve [Formula: see text] versus T, is evaluated and discussed.
GAUGE FLUCTUATIONS IN A RVB THEORY OF D-WAVE SUPERCONDUCTING CUPRATES
Authors: LEE DUNG-HAI
Published: July 2002

We present a new, asymptotic exact, theory for the U(1) gauge fluctuations on top of the d-wave RVB mean-field theory of the high Tc cuprates. After integrating out the gauge fluctuations exactly we obtain an unconstrained theory of gapless fermion excitations coupling to superconducting phase fluctuations. Several salient features of this theory will be discussed.
OPTICAL PROPERTIES OF ANATASE TiO2 UNDER THE HIGH PRESSURE
Authors: SEKIYA TAKAO , OHTA SHINSUKE , KURITA SUSUMU
Published: July 2002

Optical absorption, luminescence and Raman spectra were measured for anatase TiO 2 under high pressures. The pressure dependence of Raman frequencies is determined. The absorption edge of anatase shifts to higher energy side with increasing pressure and the edge jumps abruptly to lower energy side on the phase transition. A broad luminescence band of anatase shifts also to higher energy side with increasing pressure. These experimental results reveal that the pressure-induced phase transition from anatase to high-pressure phase arises in the range of 4.0-4.6 GPa.
STUDYING NON-UNIFORM ELECTRODEPOSITION USING THE WIRE BEAM ELECTRODE METHOD
Authors: TAN YONG-JUN
Published: July 2002

Nonuniform electrodeposition is a major concern in almost every practical electrodeposition application. The ablility to control nonuniformity in electrodeposition is the key to successful plating for corrosion resistance, and more especially to meeting the very exacting requirements of electroforming, electrodeposition. This paper presents a novel technique namely the wire beam electrode (WBE) for characterizing and monitoring nonuniform electroplating processes. For the first time, the nonuniform distribution of electroplating currents (NDEC) has been mapped. Preliminary experimental results indicated that electrochemical heterogeneity was the key factor affecting NDEC. The secondary current distribution, rather than the primary current distribution, played a major role in determining the NDEC. This work suggests that the WBE is a practical tool for characterizing and optimizing electrodeposition processes and for verifying the accuracy and completeness of mathematic modelling of electrodeposition processes.
Epitaxial Growth and Characterisation of Artificial and Superconducting Superlattices Deposited by PLD
Authors: Marré D. , Braccini V. , Canesi A. , Gariglio S. , Pallecchi I. , Putti M. , Siri A. S. , Arciprete F. , Balestrino G. , Medaglia P. G. , Petrocelli G.
Published: July 2002

Thin films and artificial materials deposition, applied to the study of high temperature superconductors, can be a powerful method to achieve better comprehension of the conduction mechanisms in these materials and, in perspective, to obtain new superconducting compounds. We simulate the layered structure of the superconducting oxides by alternating infinite layer compounds ( CaCuO 2, SrCuO 2, BaCuO 2) both pure and doped either with chemical substitutions or stoichiometry variations. By the first way, we obtained superlattices with a semiconducting electrical behaviour, probably because of the disorder induced by such high chemical substitutions. The second way led to superconducting films with transition temperatures around 80 K and low anisotropy. Furthermore, their artificial nature offers an unique possibility of analysing the influence of the structural properties on the superconducting behaviour, such as the correlation between the number of CuO 2 planes contained in the infinite layer block ( CaCuO 2) and the transport properties.
GAUSSIAN DOMINATION AND BOSE–EINSTEIN CONDENSATION IN THE INTERACTING BOSON GAS
Authors: CORGINI M. , SANKOVICH D. P.
Published: July 2002

A Davies model of an imperfect boson gas is considered. The model includes not only a convex, but also a concave type of an interaction function which depends on a dencity operator. A sufficient condition of the Bose–Einstein condensation is proved. An exact value of the critical temperature is obtained.
EXACT GROUND-STATE PROPERTIES OF ONE-DIMENSIONAL HUBBARD MODEL IN THE PRESENCE OF MAGNETIC FIELD
Authors: Yang C. , Kocharian A. N. , Chiang Y. L.
Published: July 2002

The exact phase diagram and the ground-state properties of the one-dimensional Hubbard model with arbitrary on-site interaction of electrons are calculated over a wide range of magnetic field and electron concentrations by means of the Bethe-ansatz formalism. The ground-state properties, including the total energy, the average spin (magnetization) and spin (magnetic) susceptibility are investigated for both signs of the interaction strength U/t. The critical behavior near the onset of magnetization and magnetic saturation are also analyzed. At the onset of magnetization and near the magnetic saturation the spin susceptibility χ diverges at all U/t for half-filling case n=1, whereas for n≠1 it is always finite. The reverse susceptibility χ-1(U) exhibits anomalous hump, which increases with h or n, and shows discontinuity as U/t→±0 at infinitesimal h→0. The analytical results for the ground-state properties in strong and weak interaction limits are in full agreement with our numerical calculations.
GAP ENERGY, ISOTOPE EFFECT AND COHERENCE LENGTH IN HIGH Tc-OXIDES
Authors: BECHLAGHEM A. , MOSTEFA M. , ZANOUN Y.
Published: July 2002

The model recently developed by Getino et al. to study the gap energy in the van Hove scenario in high-T c oxides is extended to study the isotope effect and the coherence length in these materials. We propose a more realistic model by: (1) adding a constant term to the singular logarithmic contribution, within the weak coupling BCS theory and a phonon mediated interaction; (2) assuming the Fermi level lies close to a van Hove singularity for optimal doping. The equations obtained from this approach, are applicable to low as well as high temperature superconductors successfully the superconducting temperature transition T c , the gap energy Δ, the isotope effect α and the coherence length ξ. For high-T c oxides, it is found that when the effective mass of carriers tends to be large, α and ξ tend to be small where T c and Δ became larges. We shown that when the effective mass of carriers is enclosed between 5 m e and 15 m e , the values obtained for these parameters are in agreement with experimental data.
ON THE OCCURENCE OF ROBUST CHAOS IN A SMOOTH SYSTEM
Authors: ANDRECUT M. , ALI M. K.
Published: July 2002

We investigate the occurrence of robust chaos in a smooth system. We present a general theorem and a practical procedure for constructing S-unimodal maps that generate robust chaos. This result is contrary to the hypothesis that robust chaos cannot exist in smooth systems.