bluuebunny/crossref_metadata_2025 huggingface dataset:
Workplace bullying and sickness absence in hospital staff
Authors: Kivimäki Mika , Elovainio Marko , Vahtera Jussi
Published: July 2002

OBJECTIVES

In the past, evidence on the negative consequences of workplace bullying has been limited to cross sectional studies of self reported bullying. In this study, these consequences were examined prospectively by focusing on sickness absence in hospital staff.

METHODS

The Poisson regression analyses of medically certified spells (⩾4 days) and self certified spells (1–3 days) of sickness absence, relating to bullying and other predictors of health, were based on a cohort of 674 male and 4981 female hospital employees aged 19–63 years. Data on sickness absence were gathered from employers' registers. Bullying and other predictors of health were measured by a questionnaire survey.

RESULTS

302 (5%) of the employees reported being victims of bullying. They did not differ from the other employees in terms of sex, age, occupation, type of job contract, hours of work, income, smoking, alcohol consumption, or physical activity. Victims of bullying had higher body mass and prevalence of chronic disease, and their rates of medically and self certified spells of sickness absence were 1.5 (95% confidence interval (95% CI) 1.3 to 1.7) and 1.2 (1.1 to 1.4) times higher than those of the rest of the staff. The rate ratios remained significant after adjustment for demographic data, occupational background, behaviour involving risks to health, baseline health status, and sickness absence.

CONCLUSION

Workplace bullying is associated with an increase in the sickness absenteeism of the hospital staff. Targets of bullying seem not to belong to any distinct group with certain demographic characteristics or occupational background.
Occupation and small bowel adenocarcinoma: a European case-control study
Authors: Kaerlev Linda , Teglbjaerg Peter Stubbe , Sabroe Svend , Kolstad Henrik A , Ahrens Wolfgang , Eriksson Mikael , González Agustin Llopis , Guénel Pascal , Hardell Lennart , Launoy Guy , Merler Enzo , Merletti Franco , Suárez-Varela María M Morales , Stang Andreas
Published: July 2002

OBJECTIVES

Because of the rarity of small bowel adenocarcinoma (SBA), little is known about the aetiology of this disease. This study aimed to identify occupational clustering of cases SBA as a systematic approach to new hypotheses on the aetiology of this disease.

METHODS

A European multicentre case-control study was conducted in 1995–7, inclusive. Incident cases aged 35–69 years with SBA (n=168) were recruited before acceptance by a pathologist. Altogether 107 cases and 3915 controls were accepted, of which 79 cases, 579 colon cancer controls, and 2070 population controls were interviewed.

RESULTS

The strongest industrial risk factors for SBA taking account of 10 years' exposure lag were dry cleaning, manufacture of workwear, mixed farming (women), and manufacture of motor vehicles (men). A significantly increased risk of SBA (odds ratio (OR) and 95% confidence interval (95% CI)) was found among men employed as building caretakers, OR 6.7 (1.7 to 26.0) and women employed as housekeepers, OR 2.2 (1.1 to 4.9); general farm labourers, OR 4.7 (1.8 to 12.2); dockers, OR 2.9 (1.0 to 8.2); dry cleaners or launderers, OR 4.1 (1.2 to 13.6); and textile workers (sewers or embroiders), OR 2.6 (1.0 to 6.8). For the last four groups, together with welders OR 2.7 (1.1 to 6.6) (men) an exposure-response pattern was found when calculating the ORs for jobs held 1–5 years and >5 years, with never having held the job as reference. The ORs (95% CIs) for 1–5 years and >5 years were 4.3 (0.4 to 44.0) and 3.5 (0.9 to 13.7), 3.0 (0.3 to 26.2) and 4.3 (0.9 to 21.2), 4.6 (0.4 to 48.1) and 11.0 (2.0 to 60.4), 1.3 (0.2 to 11.0) and 5.8 (2.0 to 17.2), and 2.8 (0.3 to 23.8) and 4.6 (1.3 to 16.6), respectively, for each of these occupations. Among welders, people performing semiautomatic arc welding (MIG/MAG) were identified as a high risk group (OR 5.0 (1.3 to 19.6)).

CONCLUSIONS

This explorative study suggests an increased occurrence of SBA in certain occupations, which needs further evaluation.
Occupational exposures and pancreatic cancer: a meta-analysis
Authors: Ojajärvi I Anneli , Partanen Timo J , Ahlbom Anders , Boffetta Paolo , Hakulinen Timo , Jourenkova Nadia , Kauppinen Timo P , Kogevinas Manolis , Porta Miquel , Vainio Harri U , Weiderpass Elisabete , Wesseling Catharina H
Published: July 2002

OBJECTIVES

Consolidation of epidemiological data on pancreatic cancer and worksite exposures.

METHODS

Publications during 1969–98 were surveyed. Studies without verified exposures were excluded. Meta-analyses were conducted on data from 92 studies covering 161 populations, with results for 23 agents or groups of agents. With a standard format, five epidemiologists extracted risk estimates and variables of the structure and quality of each study. The extracted data were centrally checked. Random meta-models were applied.

RESULTS

Based on 20 populations, exposure to chlorinated hydrocarbon (CHC) solvents and related compounds was associated with a meta-risk ratio (MRR) of 1.4 (95% confidence interval (95% CI) 1.0 to 1.8). Nickel and nickel compounds were considered in four populations (1.9; 1.2 to 3.2). Excesses were found also for chromium and chromium compounds (1.4; 0.9 to 2.3), polycyclic aromatic hydrocarbons (PAHs) (1.5; 0.9 to 2.5), organochlorine insecticides (1.5; 0.6 to 3.7), silica dust (1.4; 0.9 to 2.0), and aliphatic and alicyclic hydrocarbon solvents (1.3; 0.8 to 2.8). Evidence on pancreatic carcinogenicity was weak or non-positive for the following agents: acrylonitrile (1.1; 0.0 to 6.2); arsenic (1.0; 0.6 to 1.5); asbestos (1.1; 0.9 to 1.5); diesel engine exhaust (1.0; 0.9 to 1.3); electromagnetic fields (1.1; 0.8 to 1.4); formaldehyde (0.8; 0.5 to 1.0); flour dust (1.1; 0.3 to 3.2); cadmium and cadmium compounds (0.7; 0.4 to 1.4); gasoline (1.0; 0.8 to 1.2); herbicides (1.0; 0.8 to 1.3); iron and iron compounds (1.3; 0.7 to 2.5); lead and lead compounds (1.1; 0.8 to 1.5); man-made vitreous fibres (1.0; 0.6 to 1.6); oil mist (0.9; 0.8 to 1.0); and wood dust (1.1; 0.9 to 2.5). The occupational aetiological fraction of pancreatic cancer was estimated at 12%. In a subpopulation exposed to CHC solvents and related compounds, it was 29%; to chromium and chromium compounds, 23%; to nickel and nickel compounds, 47%; to insecticides, 33%; and to PAHs, 33%.

CONCLUSION

Occupational exposures may increase risk of pancreatic cancer. High quality studies are called for on interactions between occupational, environmental, and lifestyle factors as well as interactions between genes and the environment.
Exposure to cold and draught, alcohol consumption, and the NS-phenotype are associated with chronic bronchitis: an epidemiological investigation of 3387 men aged 53–75 years: the Copenhagen Male Study
Authors: Suadicani P , Hein H O , Meyer H W , Gyntelberg F
Published: July 2002

OBJECTIVES

This study was performed to estimate the strength of association between chronic bronchitis and lifetime exposure to occupational factors, current lifestyle, and the NS-phenotype in the MNS blood group among middle aged and elderly men.

METHODS

The study was carried out within the frameworks of the Copenhagen Male Study. Of 3387 men 3331 men with a mean age of 63 (range 53–75) years could be classified by prevalence of chronic bronchitis. As well as the completion of a large questionnaire on health, lifestyle, and working conditions, all participants had a thorough examination, including measurements of height and weight and blood pressure and a venous blood sample was taken for the measurement of serum cotinine and MNS typing; 16.5% of the men had the NS-phenotype. Chronic bronchitis was defined as cough and phlegm lasting 3 months or more for at least 2 years; 14.6% had chronic bronchitis.

RESULTS

Smoking and smoke inhalation were the factors most strongly associated with prevalence of chronic bronchitis. There were three major new findings: (a) long term (>5 years) occupational exposure to cold and draught was associated with a significantly increased prevalence of chronic bronchitis; compared with others, and adjusted for confounders, the odds ratio (OR) with 95% confidence interval (95% CI) was 1.4 (1.1 to 1.7), p=0.004; (b) a significant J shaped association existed between alcohol use and bronchitis, p<0.001, with the lowest prevalence found among moderate users; (c) a significant gene by environment association existed between smoking and the NS-phenotype in the MNS blood group; only among smokers was the NS-phenotype associated with a significantly decreased risk of chronic bronchitis, OR 0.67 (0.47-0.97), p=0.02. Other well known associations between dust, fumes, and even exposure to solvents and bronchitis were confirmed.

CONCLUSION

The results emphasise the multifactorial nature of chronic bronchitis, and show some hitherto unrecognised associations between cold and draught exposure, alcohol consumption, and the NS-phenotype and chronic bronchitis.
Physical, psychosocial, and organisational factors relative to sickness absence: a study based on Sweden Post
Authors: Voss M , Floderus B , Diderichsen F
Published: July 2002

OBJECTIVE

To analyse incidence of sickness for women and men relative to potential aetiological factors at work—physical, psychosocial, and organisational.

METHODS

The study group comprised 1557 female and 1913 male employees of Sweden Post. Sickness absence was measured by incidence of sickness (sick leave events and person-days at risk). Information on explanatory factors was obtained by a postal questionnaire, and incidence of sickness was based on administrative files of the company.

RESULTS

Complaints about heavy lifting and monotonous movements were associated with increased risk of high incidence of sickness among both women and men. For heavy lifting, an odds ratio (OR) of 1.70 (95% confidence interval (95% CI) 1.22 to 2.39) among women, and OR 1.70 (1.20 to 2.41) among men was found. For monotonous movements the risk estimates were OR 1.42 (1.03 to 1.97) and OR 1.45 (1.08 to 1.95) for women and men, respectively. Working instead of taking sick leave when ill, was more prevalent in the group with a high incidence of sickness (OR 1.74 (1.30 to 2.33) for women, OR 1.60 (1.22 to 2.10) for men). Overtime work of more than 50 hours a year was linked with low incidence of sickness for women and men. Among women, 16% reported bullying at the workplace, which was linked with a doubled risk of high incidence of sickness (OR 1.91 (1.31 to 2.77)). For men, the strongest association was found for those reporting anxiety about reorganisation of the workplace (OR 1.93 (1.34 to 2.77)).

CONCLUSIONS

Certain physical, psychosocial, and organisational factors were important determinants of incidence of sickness, independently of each other. Some of the associations were sex specific.
Increased morbidity from nasopharyngeal carcinoma and chronic pharyngitis or sinusitis among workers at a newspaper printing company
Authors: Liu Y-H , Du C-L , Lin C-T , Chan C-C , Chen C-J , Wang J-D
Published: July 2002

Objectives: To determine the association between printing works and nasopharygeal carcinoma as well as other diseases.

Methods: Demographic data were obtained for those who had worked in a particular newspaper company since its establishment in 1950. Through access to the data bank of the hospital records of the Labor Insurance Bureau for 1985–94, all workers were identified who had been admitted to hospital during their employment in the newspaper company. Multiple logistic regressions were performed to estimate the adjusted morbidity odds ratio (OR) for various diseases among the printing workers with cardiovascular diseases as the reference diseases. Biopsy specimens from patients with nasopharyngeal carcinoma were all subjected to in situ hybridisation of Epstein-Barr virus (EBV), and colocalisation of EBV and secretor component protein.

Results: Of the 1564 people who had worked in this company, 579 of them were admitted to hospital at least once. Five out of 144 printing workers admitted to hospital were diagnosed with nasopharyngeal carcinoma compared with none of the other 435 non-printing workers admitted to hospital. The morbidity OR for nasopharyngeal carcinoma in printing workers was 57.0 (95% confidence interval (95% CI) 2.8 to 1155.3). The morbidity OR for benign skin tumours was 28.0 (95% CI 2.7 to 293.1). Chronic pharyngitis or sinusitis also showed significant relations with printing works with a morbidity OR 29.4 (95% CI 1.7 to 514.7). Using all other diseases as the reference diseases for calculation of morbidity ORs still showed a similar trend. In situ hybridisation of EBV encoded small nuclear RNA-1 (EBER-1) showed tumour cells free of the EBV in each biopsy specimen. Colocalisation of EBER-1 and secretor component showed that some tumour cells contained both secretor component and EBV signal in each case.

Conclusion: Printing works are associated with an increased risk of nasopharyngeal carcinoma, benign skin tumours, chronic pharyngitis or sinusitis, chronic liver diseases, and mechanical injuries. Induction of the development of nasopharyngeal carcinoma is probably not related to EBV infection in these patients.
Influenza and pneumococcal vaccination: patient perceptions
Authors: Findlay Paul F , Gibbons Y M , Primrose W R , Ellis G , Downie G
Published: July 2002

The efficacy of the influenza vaccine in reducing mortality and hospital admissions is established, particularly in the elderly. However, up to 50% of those at risk do not receive the vaccine. These patients are also at risk from pneumococcal infection and there is considerable overlap between the target group for each vaccine.

This study sought to identify at risk individuals from consecutive admissions to an acute geriatric unit and to gain an insight into their perceptions with regard to vaccination. The awareness of each vaccine was recorded, together with the vaccination history.

Seventy four per cent of the final cohort had heard of the influenza vaccine, while only 13% had heard of the pneumococcal vaccine. Fifty per cent perceived themselves to be at risk from influenza and its complications and 87% of the cohort believed it to be a serious infection.

Influenza vaccine was judged to confer good protection by 72% of the sample and yet up to 50% believed that the vaccine can make the recipient ill.

Influenza is perceived as a serious infection by patients and yet many do not believe themselves to be at particular risk. Although influenza vaccination is believed to confer protection, the decision whether, or not, to accept the vaccine is coloured by many factors, including popular myths and anecdotal information from friends and relatives. The uptake of influenza vaccine is suboptimal and the awareness of the pneumococcal vaccine certainly in the elderly is poor. The need for a comprehensive nationwide education campaign promoting both influenza and pneumococcal vaccine is highlighted.
Changing face of adult coeliac disease: experience of a single university hospital in South Yorkshire
Authors: Sanders D S , Hurlstone D P , Stokes R O , Rashid F , Milford-Ward A , Hadjivassiliou M , Lobo A J
Published: July 2002

Objective

To determine the incidence and presenting features of adult coeliac disease in a single university hospital in South Yorkshire.

Design

A retrospective case finding study. Data were obtained from pathology and immunology databases, clinical notes, dietetic records, and patient questionnaires.

Setting

Royal Hallamshire Hospital in South Yorkshire, England.

Participants

All recorded cases of coeliac disease.

Main outcome measures: Crude annual incidence rates for coeliac disease was obtained. The numbers of coeliac antibody profiles requested per year from the Royal Hallamshire Hospital were ascertained. Age at diagnosis, sex, year of diagnosis, presenting symptoms, associated conditions, and delay in diagnosis was documented. In addition the specialty of the clinician who made the diagnosis was noted.

Results

There were 264 cases in total (male n=86, ratio 1:2). Mean age at diagnosis was 44.9 years (range 1–82, median 44.5). A trend was observed from 1990 to 2000 inclusive, of an annual increase in the incidence of coeliac disease. There has been a coincidental increase in the measurement of associated antibodies. Although 28.4% of patients presented with gastrointestinal symptoms, 20.1% had iron deficiency anaemia. The ratio of typical to atypical symptoms was 1:2.5. (single sample test of proportions p<0.001). The diagnosis was made by a gastroenterologist in only 52.7% of cases. The median duration of symptoms before the diagnosis of coeliac disease was 4.9 years (range 0.25–16 years).

Conclusion

Coeliac disease is now presenting more commonly without gastrointestinal symptoms and often to specialties other than gastroenterology. Although more cases are diagnosed, this may be a reflection of increasing recognition rather than a true increase in incidence.
News media coverage of smoking and health is associated with changes in population rates of smoking cessation but not initiation
Authors: Pierce John P , Gilpin Elizabeth A
Published: July 2002

OBJECTIVE

To determine whether changes in news media coverage of smoking and health issues are associated with changes in smoking behaviour in the USA.

DESIGN AND MAIN OUTCOME MEASURES

Issue importance in the US news media is assessed by the number of articles published annually in major magazines indexed inThe Reader's Guide to Periodical Literature. Annual incidence rates for cessation and initiation in the USA were computed from the large, representative National Health Interview Surveys (1965–1992). Patterns in cessation incidence were considered for ages 20–34 years and 35–50 years. Initiation incidence was examined for adolescents (14–17 years) and young adults (18–21 years) of both sexes.

RESULTS

From 1950 to the early 1980s, the annual incidence of cessation in the USA mirrored the pattern of news media coverage of smoking and health, particularly for middle aged smokers. Cessation rates in younger adults increased considerably when secondhand smoke concerns started to increase in the US population. Incidence of initiation in young adults did not start to decline until the beginning of the public health campaign against smoking in the 1960s. Among adolescents, incidence rates did not start to decline until the 1970s, after the broadcast ban on cigarette advertising.

CONCLUSIONS

The level of coverage of smoking and health in the news media may play an important role in determining the rate of population smoking cessation, but not initiation. In countries where cessation has lagged, advocates should work to increase the newsworthiness of smoking and health issues.
Is the standard compliance check protocol a valid measure of the accessibility of tobacco to underage smokers?
Authors: DiFranza Joseph R , Savageau Judith A , Bouchard Joseph
Published: July 2002

OBJECTIVE

To determine if the standard compliance check protocol is a valid measure of the experience of underage smokers when purchasing tobacco in unfamiliar communities.

SETTING

160 tobacco outlets in eight Massachusetts communities where underage tobacco sales laws are vigorously enforced.

PROCEDURE

Completed purchase rates were compared between underage smokers who behaved normally and inexperienced non-smoking youths who were not allowed to lie or present proof of age (ID).

RESULTS

The “smoker protocol” increased the likelihood of a sale nearly sixfold over that for the non-smokers (odds ratio (OR) 5.7, 95% confidence interval (CI) 1.5 to 22). When the youths presented an ID with an underage birth date, the odds of a completed sale increased dramatically (OR 27, 95% CI 3.4 to 212). Clerks judged to be under 21 years of age were seven times more likely to make an illegal sale (OR 7.6, 95% CI 2.4 to 24.0).

CONCLUSIONS

Commonly used compliance check protocols are too artificial to reflect accurately the experience of underage smokers. The validity of compliance checks might be improved by having youths present ID, and by employing either tobacco users, or non-tobacco users who are sufficiently experienced to mimic the self confidence exhibited by tobacco users in this situation. Consideration should be given to prohibiting the sale of tobacco by individuals under 21 years of age.
Cigar magazines: using tobacco to sell a lifestyle
Authors: Wenger Lynn D , Malone Ruth E , George Annie , Bero Lisa A
Published: July 2002

OBJECTIVE

To assess the content of two cigar “lifestyle” magazines,Cigar AficionadoandSmoke.

DESIGN

Content analysis of cigar focused articles.

SUBJECTS

Cigar focused articles (n = 353) fromCigar AficionadoandSmoke magazines.

MAIN OUTCOME MEASURES

Primary focus; mention of health effects, environmental tobacco smoke, or scientific research; quotation and description of individuals; characteristics such as sex, age, ethnicity, smoking status, affiliation, and stance towards cigars; and overall image of cigars.

RESULTS

Cigar business-focused articles were the largest category (40%, n = 143), followed by articles about cigar events (12%, n = 42). Notable were articles featuring cigar benefits to raise money for health charities. Celebrities were featured in 34% (n = 121) of articles and 96% (n = 271) favoured cigar use. Only four (1%) articles featured health effects of cigars as a primary focus.

CONCLUSIONS

Cigar AficionadoandSmokebroke new ground in tobacco marketing by combining promotion of product, lifestyle, and industry in the same vehicle and linking the medium directly to product related events that extended its reach. The creation and marketing of new tobacco use sites challenges the increasing “isolation” of smokers, and positions cigar use as a socially welcome relief from restrictions. Public health advocates should anticipate and challenge other new tobacco marketing vehicles as communications technologies advance and public spaces for smoking shrink.
Seismic refraction profiles in the Gulf of Saint Lawrence and implications for extent of continuous Grenville lower crust
Authors: Jackson H R
Published: July 2002

Near the exposed Grenville craton, a two-layer crust with velocities of 6.2 km s1 and 6.65 km s1 and low gradient is measured. The 6.65 km s1 velocity is observed at the shallow depth of 15 km and the Moho at greater than 40 km depth. Towards the Appalachian orogen, a southwards dipping ramp is developed in the mid crust on the top of the 6.65 km s1 layer. A collinear reflection profile confirms the southwards dipping ramp, the shallowing Moho and the lateral changes in the lower crust. A published refraction profile that crosses this reflection profile near the southern end confirms the termination of the 6.65 km s1 layer and its replacement by a slower velocity. With the publishing of wide angle reflectionrefraction (WAR) profile 88-2, two pairs of lines are now available in the gulf that cross the craton into the orogen with both WAR and deep seismic reflection coverage. The combined data sets are used to distinguish the Grenville lower crustal block based on patterns of reflectivity and associated velocities. Near the Gaspé, the Grenville lower crustal block extends southwestward and, by extrapolation of the tectonostratigraphic zones offshore, underlies the Humber zone. In contrast, profiles in the gulf to the west of Newfoundland imply the continuous Grenville lower crustal block terminates seaward of the Humber surface terrane. Along-strike variations in the extent of Grenville lower crustal block beneath the northern Appalachians are suggested as an important factor in determining the style of crustal deformation.
Comparison of the frequentist properties of Bayes and the maximum likelihood estimators in an age-structured fish stock assessment model
Authors: Nielsen Anders , Lewy Peter
Published: July 2002

A simulation study was carried out for a separable fish stock assessment model including commercial and survey catch-at-age and effort data. All catches are considered stochastic variables subject to sampling and process variations. The results showed that the Bayes estimator of spawning biomass is a useful but slightly biased estimator for which the frequentist variance can be estimated by the posterior variance. Comparisons further show that the Bayes estimator is better than the maximum likelihood in the sense that it is less biased and, surprisingly, has a much lesser variance. The catch simulations were based on the North Sea plaice (Pleuronectes platessa) stock and fishery data.
A novel double anchored steel fiber for shotcrete
Authors: Banthia N , Armelin H
Published: July 2002

Given the high deformability requirements of shotcrete in repair, rehabilitation, slope stabilization, ground support, and other applications, the use of fibers in shotcrete is growing. Growing also are challenges surrounding the use of fibers in shotcrete not the least of which are a high fiber rebound in the dry process, lack of standardized test techniques, and a poor understanding of reinforcement mechanisms. In the context of rebound, unfortunately, the requirements for a low rebound often clash with the requirements for a high material toughness. This paper describes a new fiber developed at The University of British Columbia where a rational balance was sought between the conflicting requirements of rebound reduction and a high material toughness. The new fiber is based on a double anchoring principle and is optimized for both reduced rebound and a high toughness in hardened shotcrete.Key words: shotcrete, fiber reinforcement, steel fiber, toughness, rebound.
Removal of Aroclor 1016 from contaminated soil by Solvent Extraction Soil Agglomeration Process
Authors: Majid A , Argue S , Sparks B D
Published: July 2002

This communication reports the results of a study to assess the suitability of the National Research Council of Canada's Solvent Extraction Soil Remediation (SESR) process to effectively remediate soils contaminated with PCBs. A series of small-scale batch extraction tests were carried out using a loamy clay soil sample spiked with Aroclor 1016. The variables examined included the effects of solvent type, water addition, agglomerate size, and extraction additives. Aroclor 1016 recovery rates for the SESR process were higher than those found for high shear agitation of soil slurries without agglomeration and Soxhlet extraction (93.9 ± 1.9, 90.6 ± 1.5 and 82.7 ± 0.9% respectively). A two-stage extraction process, with a series of three wash steps incorporated into the solidliquid separation operation, produced a treated soil with an average Aroclor 1016 concentration of 49 ± 8 mg/kg on a dry weight basis (95.4 ± 2.4% removed). Key words: PCBs, soil remediation, agglomeration, solvent extraction.
The 2000 R.M. Hardy Lecture: Full-scale hydraulic performance of soilbentonite and compacted clay liners
Authors: Chapuis Robert P
Published: July 2002

The results of laboratory and in situ permeability tests can be used to predict the total leakage rate of a soilbentonite or clay liner. This prediction, however, ignores the large influence that minor defects may have on the total leakage. In Quebec, hundreds of municipal wastewater ponds have been filled with water to measure their total leakage rate before approval. The design criteria and the equations to be used for the full-scale performance test are briefly reviewed with their capacities to detect hydraulic deficiencies. Several case histories are presented to illustrate various problems: excessive leakage of a stable soilbentonite mix, washing of bentonite in a soilbentonite mix, internal erosion of a natural clay liner through an inadequate sand filter, and effects of freezing on the total leakage of a clay liner.Key words: liner, clay, bentonite, permeability, performance, full-scale test
Stress–strain behaviour of unsaturated soil in true triaxial tests
Authors: Matsuoka Hajime , Sun De'an , Kogane Akiteru , Fukuzawa Nobuhiko , Ichihara Wataru
Published: July 2002

A suction-controlled true triaxial apparatus for unsaturated soil was developed from the existing true triaxial apparatus for sand by attaching a device to supply matric suction to specimens. Using the developed apparatus, true triaxial tests (σ1 [Formula: see text] σ2 [Formula: see text] σ3; where σ1, σ2, and σ3 are the three different principal stresses) on an unsaturated silty soil were carried out under constant suction using the negative pore-water pressure method (s = uw > 0; ua = 0) for applying the matric suction, s (s = ua  uw; where ua is the pore-air pressure and uw is the pore-water pressure). It was found that the true triaxial test results under three different principal stresses are uniquely arranged on the "extended spatially mobilized plane (extended SMP)" for frictional and cohesive materials that is modified from the original SMP for frictional materials by introducing "a bonding stress, σ0 (= c·cotϕ, where c is cohesion and ϕ is the internal friction angle)." It was also found that the shear strengths of the unsaturated silty clay obtained by the true triaxial apparatus nearly agree with the extended SMP failure criterion (Î1Î2/Î3 = constant, where Î1, Î2, and Î3 are the first, second, and third invariants of the translated stress tensor). The measured stress-strain-strength behaviour of the unsaturated soil in three-dimensional (3D) stresses can be well simulated by an elastoplastic model with the transformed stress based on the extended SMP criterion and a special hardening parameter.Key words: failure criterion, shear strength, special shear test, suction, stress path, unsaturated soil.
Asymmetric total synthesis of (+)-exo-brevicomin based on enantioconvergent biocatalytic hydrolysis of an alkene-functionalized 2,3-disubstituted epoxide
Authors: Mayer Sandra F , Mang Harald , Steinreiber Andreas , Saf Robert , Faber Kurt
Published: July 2002

A short total asymmetric synthesis of (+)-exo- and ()-endo-brevicomin ((+)-exo-3 and ()-endo-3), which are components of the attracting pheromone system of several bark-beetle species belonging to the genera Dendroctonus and Dryocoetes, was accomplished via a chemoenzymatic protocol. The key step consisted of biocatalytic hydrolysis by bacterial epoxide hydrolases of cis-configured 2,3-disubstituted oxiranes bearing olefinic side chains. This reaction proceeded in an enantioconvergent fashion, by affording a single enantiomeric vic-diol from the rac-epoxide in up to 92% ee and 83% isolated yield.Key words: bacterial epoxide hydrolase, 2,3-disubstituted oxirane, enantioconvergent hydrolysis, (+)-exo-brevicomin, ()-endo-brevicomin.
MAPPING ARBITRARY HETEROGENEOUS TASK GRAPHS ONTO ARBITRARY HETEROGENEOUS SYSTEM GRAPH
Authors: Eshaghian Mary Mehrnoosh
Published: July 2002

In this paper, a generic technique for mapping arbitrary heterogeneous task graphs onto arbitrary heterogeneous system graphs is presented. The heterogeneous task and system graphs studied in this paper have nonuniform computation and communication weights associated with the nodes and the edges. Two clustering algorithms have been proposed that can be used to obtain a multilayer clustered graph called a Spec graph from a given task graph and a multilayer clustered graph called a Rep graph from a given system graph. We present a mapping algorithm that produces a suboptimal matching of a given Spec graph containing M task modules onto a Rep graph of N processors, in O(M2) time, where N ≤ M. Our experimental results indicate that our mapping algorithm is the fastest one and generates results that are better than, or similar to, those of other leading techniques, some of which work only for restricted task or system graphs.
SOLVING ROSTERING TASKS BY GENERIC METHODS FOR CONSTRAINT OPTIMIZATION
Authors: AUF'M HOFE HARALD MEYER
Published: July 2002

Based on experiences with the ORBIS·Dienstplan-system, this paper described how constraint processing can be used to implement automatic rostering systems. In practice, nurse rostering problems have many varying parameters. Hence, rostering requires a flexible formalism for representing the variants of the problem as well as a robust search procedure that is able to cope with all problem instances. On the one hand, the used constraint formalism allows the integration of very fine-grained optimization tasks by fuzzy constraints, which a roster may partially satisfy and partially violate. On the other hand, the described system uses an any-time algorithm to search good rosters. A meta-problem is generated from the constraint representation of the problem to identify reasons for constraint violations in order to improve the search for improvement steps.
ORBITAL STABILITY OF STANDING WAVES FOR THE NONLINEAR SCHRÖDINGER EQUATION WITH POTENTIAL
Authors: CID CARLOS , FELMER PATRICIO
Published: July 2002

We prove existence and orbital stability of standing waves for the nonlinear Schrödinger equation [Formula: see text] concentrating near a possibly degenerate local minimum of the potential V, when the Plank's constant ℏ is small enough. Our method applies to general nonlinearities, including f(s)=sp - 1 with p ∈ (1,1 + 4/N), but does not require uniqueness nor non-degeneracy of the limiting equation.
THE "INFRARED CATASTROPHE": WHEN DOES IT TRASH FERMI LIQUID THEORY?
Authors: ANDERSON P. W.
Published: July 2002

We give an historical discussion of the "infrared catastrophe" and the "x-ray edge anomalies" of Mahan associated with scatterers in a Fermi sea of electrons. The infrared catastrophe provides a perspicuous way into understanding the difficulties with many-body perturbation theory which have recently been discovered as a result of a study of high Tc superconductivity, and we show how this "catastrophe" is avoided in some cases, but cannot be avoided in the one and 2-dimensional electron gas systems. Finally, we indicate the new type of theory which is necessary in the event of such a breakdown.
CURVATURE-INDUCED BOUND STATES IN QUANTUM WAVEGUIDES IN TWO AND THREE DIMENSIONS
Authors: DUCLOS P. , EXNER P.
Published: July 2002

Dirichlet Laplacian on curved tubes of a constant cross section in two and three dimensions is investigated. It is shown that if the tube is non-straight and its curvature vanishes asymptotically, there is always a bound state below the bottom of the essential spectrum. An upper bound to the number of these bound states in thin tubes is derived. Furthermore, if the tube is only slightly bent, there is just one bound state; we derive its behaviour with respect to the bending angle. Finally, perturbation theory of these eigenvalues in any thin tube with respect to the tube radius is constructed and some open questions are formulated.
DIAGONAL CROSSED PRODUCTS BY DUALS OF QUASI-QUANTUM GROUPS
Authors: HAUSSER FRANK , NILL FLORIAN
Published: July 2002

A two-sided coaction [Formula: see text] of a Hopf algebra [Formula: see text] on an associative algebra ℳ is an algebra map of the form [Formula: see text] , where (λ,ρ) is a commuting pair of left and right [Formula: see text] -coactions on ℳ, respectively. Denoting the associated commuting right and left actions of the dual Hopf algebra [Formula: see text] on ℳ by ◃ and ▹, respectively, we define the diagonal crossed product[Formula: see text] to be the algebra generated by ℳ and [Formula: see text] with relations given by [Formula: see text]

We give a natural generalization of this construction to the case where [Formula: see text] is a quasi-Hopf algebra in the sense of Drinfeld and, more generally, also in the sense of Mack and Schomerus (i.e. where the coproduct Δ is non-unital). In these cases our diagonal crossed product will still be an associative algebra structure on [Formula: see text] extending [Formula: see text], even though the analogue of an ordinary crossed product [Formula: see text] in general is not well defined as an associative algebra.

Applications of our formalism include the field algebra constructions with quasi-quantum group symmetry given by G. Mack and V. Schomerus [31, 47] as well as the formulation of Hopf spin chains or lattice current algebras based on truncated quantum groups at roots of unity.

In the case [Formula: see text] and λ=ρ=Δ we obtain an explicit definition of the quantum double [Formula: see text] for quasi-Hopf algebras [Formula: see text] , which before had been described in the form of an implicit Tannaka–Krein reconstruction procedure by S. Majid [35]. We prove that [Formula: see text] is itself a (weak) quasi-bialgebra and that any diagonal crossed product [Formula: see text] naturally admits a two-sided [Formula: see text] -coaction. In particular, the above-mentioned lattice models always admit the quantum double [Formula: see text] as a localized cosymmetry, generalizing results of Nill and Szlachányi [42]. A complete proof that [Formula: see text] is even a (weak) quasi-triangular quasi-Hopf algebra will be given in a separate paper [27].
PROJECTIVITY CRITERION OF MOISHEZON SPACES AND DENSITY OF PROJECTIVE SYMPLECTIC VARIETIES
Authors: NAMIKAWA YOSHINORI
Published: July 2002

A Moishezon manifold is a projective manifold if and only if it is a Kähler manifold [13]. However, a singular Moishezon space is not generally projective even if it is a Kähler space [14]. Vuono [19] has given a projectivity criterion for Moishezon spaces with isolated singularities. In this paper we shall prove that a Moishezon space with 1-rational singularities is projective when it is a Kähler space (Theorem 1.6).

We shall use Theorem 1.6 to show the density of projective symplectic varieties in the Kuranishi family of a (singular) symplectic variety (Theorem 2.4), which is a generalization of the result by Fujiki [4, Theorem 4.8] to the singular case.

In the Appendix we give a supplement and a correction to the previous paper [15] where singular symplectic varieties are dealt with.
THE ROLE OF MUTATION AND POPULATION SIZE IN GENETIC ALGORITHMS APPLIED TO PHYSICS PROBLEMS
Authors: BELMONT-MORENO E.
Published: July 2002

A standard Genetic Algorithm is applied to a set of test problems, three of them taken from physics and the rest analytical expressions explicitly constructed to test search procedures. The relation between mutation rate and population size in the search for optimum performance is obtained showing similar behavior in these problems.
NONCOMMUTATIVE INSTANTONS AND THE INFORMATION METRIC
Authors: PARVIZI SHAHROKH
Published: July 2002

By using the so-called Information Metric on the moduli space of an anti-self-dual (ASD) Instanton in a self-dual (SD) noncommutative background, we investigate the geometry of moduli space. The metric is evaluated perturbatively in noncommutativity parameter and we show that by putting a cutoff in the location of instanton in the definition of Information Metric we can recover the five-dimensional space–time in the presence of a B-field. This result shows that the noncommutative YM-Instanton Moduli corresponds to D-Instanton Moduli in the gravity side where the radial and transverse location of D-Instanton correspond to YM-Instanton size and location, respectively. The match is shown in the first order of noncommutativity parameter.
HIGGS-INSPIRED CORRECTIONS TO THE RG FLOW IN THE FINITE-TEMPERATURE 3D GEORGI–GLASHOW MODEL AND ITS SU(N)-GENERALIZATION
Authors: ANTONOV DMITRI
Published: July 2002

The RG flow in the finite-temperature (2 + 1)D Georgi–Glashow model is explored in the regime when the Higgs field is not infinitely heavy, but its mass is rather of the same order of magnitude as the mass of the W-boson. The corrections to the standard RG flow are derived to the leading order in the inverse mass of the Higgs boson. The scaling of the free-energy density in the critical region and the value of the critical temperature of the Berezinsky–Kosterlitz–Thouless (BKT) phase transition are found to be unaffected by the finiteness of the Higgs–boson mass. The evolution of the Higgs mass itself is also investigated and shown to be rather weak, that enables one to treat this parameter as a constant. The same analysis is further performed in the SU (N)-case at N > 2, where the RG invariance is demonstrated to hold only approximately, in a certain sense. Modulo this approximation, the critical behavior of the SU (N)-model turns out to be identical to that of the SU(2)-one.
LIE ALGEBRA AND INVARIANT TENSOR TECHNOLOGY FOR g2
Authors: MACFARLANE A. J.
Published: July 2002

Proceeding in analogy with su (n) work on λ matrices and f- and d-tensors, this paper develops the technology of the Lie algebra g2, its seven-dimensional defining representation γ and the full set of invariant tensors that arise in relation thereto. A comprehensive listing of identities involving these tensors is given. This includes identities that depend on use of characteristic equations, especially for γ, and a good body of results involving the quadratic, sextic and (the nonprimitivity of) other Casimir operators of g2.
ENTROPY OF RANDOM VARIABLE SEQUENCE IN A PARTICULAR MARKOV CHAIN
Authors: IKEDA NOBUTOSHI
Published: July 2002

A method of estimating the number of states which are observed in a short time in a particular Markov chain is proposed. And the relation between the structure of the Markov chain and the entropy of random variable sequence is mentioned. The cases where we can use the theory properly are so limited that the validity of the method is investigated in simple examples.
STRUCTURE AND THICKNESS DEPENDENT OPTICAL PROPERTIES OF NANOCRYSTALLINE HAEMATITE THIN FILMS
Authors: RAJENDRAN M. , KRISHNA M. GHANASHYAM , BHATTACHARYA A. K.
Published: July 2002

An aqueous sol-gel process has been developed to deposit nanocrystalline haematite (α- Fe 2 O 3) thin films by dip-coating. Stable, positively charged colloidal sol particles of hydrous iron (III) oxide with an average particle size (Z av ) of 6 nm were prepared and coated onto quartz plates under controlled conditions. The sols were characterised using photon correlation spectroscopy (PCS) for Z av and size distribution. The re-dispersible gel was characterised by thermoanalytical techniques (TG-DTA) and also by isothermal heating followed by X-ray diffraction to identify the reaction pathway to form α- Fe 2 O 3. The films as deposited were X-ray amorphous up to 450°C, nan°Crystalline in the range 450 to 600°C, crystalline and single phase above 600°C. The films were optically transparent, continuous and had uniform thickness in the range between 180 nm to 1000 nm depending on deposition conditions. The optical band gap varied from 2.1 to 2.6 eV as a function of film thickness. The refractive index increased with increase in annealing temperature but decreased with film thickness.
QUANTUM EFFECTS AND BROKEN SYMMETRIES IN FRUSTRATED ANTIFERROMAGNETS
Authors: CAPRIOTTI LUCA
Published: July 2002

We investigate the interplay between frustration and zero-point quantum fluctuations in the ground state of the triangular and J1–J2 Heisenberg antiferromagnets, using finite-size spin-wave theory, exact diagonalization, and quantum Monte Carlo methods. In the triangular Heisenberg antiferromagnet, by performing a systematic size-scaling analysis, we have obtained strong evidences for a gapless spectrum and a finite value of the thermodynamic order parameter, thus confirming the existence of long-range Néel order. The good agreement between the finite-size spin-wave results and the exact and quantum Monte Carlo data also supports the reliability of the spin-wave expansion to describe both the ground state and the low-energy spin excitations of the triangular Heisenberg antiferromagnet. In the J1–J2 Heisenberg model, our results indicate the opening of a finite gap in the thermodynamic excitation spectrum at J2/J1≃0.4, marking the melting of the antiferromagnetic Néel order and the onset of a non-magnetic ground state. In order to characterize the nature of the latter quantum-disordered phase we have computed the susceptibilities for the most important crystal symmetry breaking operators. In the ordered phase the effectiveness of the spin-wave theory in reproducing the low-energy excitation spectrum suggests that the uniform spin susceptibility of the model is very close to the linear spin-wave prediction.
ADSORPTION OF HYDROGEN AND OXYGEN ON SINGLE AND DOUBLE LAYER STEPPED SI(100) SURFACES
Authors: SALMAN SAED A. , KATIRCIOĞLU ŞENAY , ERKOÇ ŞAKIR
Published: July 2002

We have investigated the electronic band structure of hydrogen and oxygen adsorbed single and double layer stepped Si(100) surfaces by Empirical Tight Binding (ETB) method. The total electronic energies of the H,O-SA, DA, DB type stepped Si(100) systems are calculated with limited number of hydrogen and oxygen atoms separately to find out the most probable adsorption sites of the adatoms in the initial stage of hydrogenation and oxidation.
Transient Grating Induced by Excitonic Polaritons in Thin Films Semiconductors
Authors: Akiyama K. , Tomita N. , Nishimura T. , Nomura Y. , Isu T.
Published: July 2002

Light propagation effects on nonlinear optical response of a size-controlled GaAs thin film at exciton resonance are investigated by transient gradient using picosecond pulses (1.5 ps). The signals are enhanced at the exciton resonance and the temporal profiles strongly depend on the excitation pulse energies. The result indicates that the nonlinear response is induced by excitonic polaritons and its decay is determined by the round-trip of the polariton in the film.
Enhancement of Exciton and Biexciton Luminescence in CuCl QDs on Dielectric Multilayers
Authors: Kurisu H. , Horie J. , Nagoya K. , Yamamoto S. , Matsuura M.
Published: July 2002

We investigated photoluminescence properties of the exciton and the biexciton in CuCl quantum dots embedded in an SiO 2 matrix on (λ/4) TiO 2/(λ/4) SiO 2 dielectric multilayers of the distributed Bragg reflector. The intensities of the free exciton luminescence band and the biexciton luminescence bands are enhanced by factors 2 and 6 times in comparison with those in only CuCl quantum dots embedded in an SiO 2 matrix. The origin of this luminescence behavior is partly reflection effects of the luminescence and excitation laser lights but additional effects need to be considered. One possible candidate is the strong exciton-photon interaction due to the confinement effect of the photons in the active layer with CuCl quantum dots.
SYNTHESIS AND OPTICAL PROPERTIES OF WATER SOLUBLE ZnSe NANOCRYSTALS
Authors: Murase N. , Gao M. Y. , Gaponik N. , Yazawa T. , Feldmann J.
Published: July 2002

ZnSe nanocrystals are prepared in water by a wet chemistry method. By selecting an appropriate pH value and surface-capping agents, a whitish blue fluorescence peaking at 470 nm is observed under ZV irradiation. The intensity of this fluorescence increases dramatically under reflux and saturates after ~ 40 hrs. The final mean size of the ZnSe nanocrystals measured by transmission electron microscopy is aboyt 2 nm in diameter. The quantum efficiency of the fluorescence form the final solution is estimated to be ~1%, although the preparation conditions have not yet been completely optimized. These properties are discussed in comparison with those of similarly prepared CdTe and differently prepared ZnSe nanocrystals.