bluuebunny/crossref_metadata_2025 huggingface dataset:
The evolution of preferences and competition: a rationalization of Veblen's theory of invidious comparisons
Authors: Eaton B. Curtis , Eswaran Mukesh
Published: October 2003

Abstract. We examine how preferences evolve by natural selection in a competitive environment similar to that characterizing much of our evolutionary past. We find that the evolutionarily stable preferences in this context exhibit a concern not only for absolute payoffs but also for relative payoffs, and that this intensifies the degree of competition relative to what obtains when players consider only absolute payoffs. We argue that this has consequences for the equilibrium population size. We argue that the premise of this analysis is consistent with the available anthropological evidence, and that the prediction is broadly consistent with the findings of experimental game theory. JEL Classification: C70

Evolution des préférences et concurrence: une rationalisation de la théorie des comparaisons désobligeantes de Veblen. Les auteurs examinent comment les préférences évoluent par sélection naturelle dans un environnement concurrentiel qui ressemble à celui qui a caractérisé notre passéévolutionnaire, c’est‐à‐dire, un environnement de chasseurs et de cueilleurs. On découvre que les préférences évolutionnairement stables dans ce contexte révèlent un intérêt non seulement pour les résultats en termes absolus mais aussi pour les résultats en termes relatifs, et que cela intensifie le degré de concurrence par rapport à ce qui se passerait si les joueurs prenaient en compte seulement les résultats en termes absolus. En travaillant contre l’espèce si l’on peut dire, la sélection naturelle des préférences réduit les niveaux d’équilibre des populations en deçà de ce qui aurait prévalu si les préférences n’avaient pas évolué. Le postulat de base sur lequel cette analyse se fonde est compatible avec les résultats des travaux anthropologiques et les prédictions sont compatibles avec les résultats des travaux en théorie des jeux expérimentale.
A cross‐country comparison of the cyclicality of real wages
Authors: Liu Haoming
Published: October 2003

Abstract.  This paper contains the first cross‐country comparison of the cyclical behaviour of real wages using microdata. After controlling for changes in labour quality, I find that real wages are strongly procyclical in Canada, the United Kingdom, and the United States. In contrast, the cyclicality of government‐published real aggregate hourly wages varies substantially across these three countries. The disparity suggests that a direct comparison of the cyclical behaviour of real aggregate wages is misleading. Finally, I show that variations in labour quality also bias the cross‐country correlation of several key labour market variables. JEL classification: J3, E3

Une comparaison transversale entre pays du caractère cyclique des salaires réels.  Ce mémoire présente la première comparaison entre pays du comportement cyclique des salaires réels à l’aide de micro‐données. Après normalisation pour tenir compte des changements dans la qualité du travail, cette étude montre que les salaires réels sont pro‐cycliques au Canada, au Royaume‐Uni et aux Etats Unis. Au contraire, le caractère cyclique des données sur les salaires horaires agrégés varie substantiellement entre ces trois pays. Cette disparité suggère qu’une comparaison directe du comportement cyclique des salaires réels agrégés peut être trompeuse. Finalement, cette étude montre que les variations dans la qualité du travail biaisent aussi les corrélations entre pays de plusieurs variables du marché du travail.
An estimated Canadian DSGE model with nominal and real rigidities
Authors: Dib Ali
Published: October 2003

Abstract.  We develop a dynamic, stochastic, general‐equilibrium (DSGE) model due to Ireland (1997) and others and estimate it for the Canadian economy to analyse the real effects of monetary policy shocks. To generate high and persistent real effects, the model combines nominal frictions in the form of costly price adjustment with real rigidities modelled as convex costs of adjusting capital and/or employment. The structural parameters identifying transmission channels are estimated econometrically using a maximum‐likelihood procedure with a Kalman filter. The estimated nominal and real rigidities impart substantial and persistent real effects following a monetary policy shock. Furthermore, the results suggest that the monetary authority has accommodated technology shocks and has successfully offset the real effects of money‐demand shocks, by actively responding to these shocks. JEL classification: E31, E32, E52

Un modèle d’équilibre général dynamique et stochastique doté de rigidités nominales et réelles et calibré avec des données canadiennes.  Dans la présente étude, nous développons un modèle d’équilibre général dynamique et stochastique (EGDS), élaboré par Ireland (1997) et d’autres, et estimons ce modèle pour l’économie canadienne. Afin de générer des effets réels considérables et persistants des chocs monétaires, nous intégrons à ce modèle des frictions nominales et réelles sous la forme de coûts d’ajustement des prix, du capital et de l’emploi. En utilisant la méthode du maximum de vraisemblance et le filtre de Kalman, nous estimons les paramètres structurels du modèle avec des données canadiennes. Les versions du modèle d’EGDS doté de rigidités nominales et réelles génèrent des effets réels significatifs et persistants en réaction à des chocs de politique monétaire. De plus, les résultats suggèrent que l’autorité monétaire réussit bien à contenir les chocs technologiques et à annuler les effets des chocs de la demande de monnaie.
Policy rule Nash equilibria
Authors: Sorger Gerhard
Published: October 2003

Abstract. We study how different types of instrument rules affect the outcome of a monetary policy game between the central bank and the private sector. Policy rules can be independent of output and a shock, functions of the shock, or functions of output. We rank the Nash equilibria generated by different types of policy rules according to the central bank's ex ante expected loss. If both players can condition on output, then the following is true: no equilibrium exists if the central bank cares much about output stability and little about price stability, and infinitely many equilibria exist otherwise. JEL classification: E52, E61

Equilibres à la Nash des règles de politique. L’auteur étudie comment le choix de divers types de règles instrumentales a un effet sur le résultat d’un jeu de politique monétaire entre la banque centrale et le secteur privé. Les règles de politique peuvent être indépendantes de la production ou d’un choc, être fonction d’un choc ou de la production. On établit un ordre des équilibres à la Nash engendrés par ces divers types de règles de politique selon la taille des pertes anticipées ex ante par la banque centrale. Si les deux joueurs fondent leur comportement sur la production, il s’ensuit que — aucun équilibre n’existe si la banque centrale est très préoccupée par la stabilité du niveau de production et peu préoccupée de la stabilité des prix, et autrement, une infinité d’équilibres existent.
Strategic policy for product R&D with symmetric costs
Authors: Jinji Naoto
Published: October 2003

Abstract.  In this paper I examine strategic policy for product R&D in an international duopoly where domestic and foreign firms are identical. It is shown that strategic R&D policy is described by a subsidy schedule contingent on firms’ quality choices. Unilateral policy enables its domestic firm to produce a high‐quality product, making equilibrium outcome unique. With two active governments, in equilibrium they implement different subsidy schedules. Two equilibrium outcomes exist, which are identical except for the identity of the countries. Thus, both countries have an equal chance to become the high‐quality exporter. Both Bertrand and Cournot cases are examined. JEL classification: F12, F13

Politique stratégique pour le R&D dans le développement de nouveaux produits quand les coûts sont symétriques.  Ce mémoire examine la politique stratégique pour le R&D dans le développement de produits nouveaux dans un duopole international où les entreprises domestique et étrangère sont identiques. On montre que cette politique est décrite par cédules de subventions qui dépendent des choix du niveau de qualité des entreprises. Une politique unilatérale permet à l’entreprise domestique de manufacturer un produit de haute qualité– ce qui engendre des résultats d’équilibre uniques. Si deux gouvernements sont actifs, en équilibre, ils mettent en place des cédules de subventions différentes. Deux résultats d’équilibre existent qui sont identiques sauf pour l’identité des pays. Donc les deux pays ont une chance égale de devenir l’exportateur du produit de haute qualité. On examine les cas de figure à la Bertrand et à la Cournot.
Consumer‐benefiting exclusive territories
Authors: Matsumura Toshihiro
Published: October 2003

Abstract.  I investigate the effect of exclusive territories, which are typical vertical controls imposed by upstream firms. Using shipping spatial models, I consider an industry that consists of many independent local markets. An upstream monopolist restricts competition between downstream firms using exclusive territories. I find that exclusive territories reduce the prices of final products in all local markets in quantity‐setting competition. In price‐setting competition, they raise prices in half the local markets, reduce them in other markets, and also reduce the total consumer surplus. JEL classification: L42, R32
Breast cancer risk in airline cabin attendants: a nested case-control study in Iceland: Table 1
Authors: Rafnsson V , Sulem P , Tulinius H , Hrafnkelsson J
Published: October 2003

Aims:To investigate whether length of employment as a cabin attendant was related to breast cancer risk, when adjusted for reproductive factors.

Methods:Age matched case-control study nested in a cohort of cabin attendants. The cases were found from a nationwide cancer registry (followed up to end of year 2000) and the reproductive factors (age at first childbirth and number of children) from a registry of childbirth, in both instances by record linkage with the cabin attendants’ identification numbers. The employment time of the cabin attendants at the airline companies and the reproductive factors had been systematically recorded prior to the diagnosis of breast cancer in the cohort. A total of 35 breast cancer cases and 140 age matched controls selected from a cohort of 1532 female cabin attendants were included in the study.

Results:The matched odds ratio from conditional logistic regression of breast cancer risk among cases and controls of cabin attendants was 5.24 (95% CI 1.58 to 17.38) for those who had five or more years of employment before 1971 compared with those with less than five years of employment before 1971, adjusted for age at first childbirth and length of employment from 1971 or later.

Conclusions:The association between length of employment and risk of breast cancer, adjusted for reproductive factors, indicates that occupational factors may be an important cause of breast cancer among cabin attendants; the association is compatible with a long induction period.
Cancer incidence in airline cabin crew: experience from Sweden
Authors: Linnersjö A , Hammar N , Dammström B-G , Johansson M , Eliasch H
Published: October 2003

Aims:To determine the cancer incidence in Swedish cabin crew.

Methods:Cancer incidence of cabin crew at the Swedish Scandinavian Airline System (SAS) (2324 women and 632 men) employed from 1957 to 1994 was determined during 1961–96 from the Swedish National Cancer Register. The cancer incidence in cabin crew was compared with that of the general Swedish population by comparing observed and expected number of cases through standardised incidence ratios (SIR). A nested case-control study was performed, including cancer cases diagnosed after 1979 and four controls per case matched by gender, age, and calendar year.

Results:The SIR for cancer overall was 1.01 (95% CI 0.78 to 1.24) for women and 1.16 (95% CI 0.76 to 1.55) for men. Both men and women had an increased incidence of malignant melanoma of the skin (SIR 2.18 and 3.66 respectively) and men of non-melanoma skin cancer (SIR 4.42). Female cabin attendants had a non-significant increase of breast cancer (SIR 1.30; 95% CI 0.85 to 1.74). No clear associations were found between length of employment or cumulative block hours and cancer incidence.

Conclusions:Swedish cabin crew had an overall cancer incidence similar to that of the general population. An increased incidence of malignant melanoma and non-melanoma skin cancer may be associated with exposure to UV radiation, either at work or outside work. An increased risk of breast cancer in female cabin crew is consistent with our results and may in part be due to differences in reproductive history.
Risk factors for cutaneous malignant melanoma among aircrews and a random sample of the population
Authors: Rafnsson V , Hrafnkelsson J , Tulinius H , Sigurgeirsson B , Hjaltalin Olafsson J
Published: October 2003

Aims:To evaluate whether a difference in the prevalence of risk factors for malignant melanoma in a random sample of the population and among pilots and cabin attendants could explain the increased incidence of malignant melanoma which had been found in previous studies of aircrews.

Methods:A questionnaire was used to collect information on hair colour, eye colour, freckles, number of naevi, family history of skin cancer and naevi, skin type, history of sunburn, sunbed, all sunscreen use, and number of sunny vacations.

Results:The 239 pilots were all males and there were 856 female cabin attendants, which were compared with 454 males and 1464 females of the same age drawn randomly from the general population. The difference in constitutional and behavioural risk factors for malignant melanoma between the aircrews and the population sample was not substantial. The aircrews had more often used sunscreen and had taken more sunny vacations than the other men and women. The predictive values for use of sunscreen were 0.88 for pilots and 0.85 for cabin attendants and the predictive values for sunny vacation were 1.36 and 1.34 respectively.

Conclusion:There was no substantial difference between the aircrew and the random sample of the population with respect to prevalence of risk factors for malignant melanoma. Thus it is unlikely that the increased incidence of malignant melanoma found in previous studies of pilots and cabin attendants can be solely explained by excessive sun exposure.
Occupational risk factors for symptomatic lumbar disc herniation; a case-control study
Authors: Seidler A , Bolm-Audorff U , Siol T , Henkel N , Fuchs C , Schug H , Leheta F , Marquardt G , Schmitt E , Ulrich P T , Beck W , Missalla A , Elsner G
Published: October 2003

Background:Previous studies mostly did not separate between symptomatic disc herniation combined with osteochondrosis/spondylosis of the lumbar spine and symptomatic disc herniation in radiographically normal intervertebral spaces. This may at least in part explain the differences in the observed risk patterns.

Aims:To investigate the possible aetiological relevance of physical and psychosocial workload to lumbar disc herniation with and without concomitant osteochondrosis/spondylosis.

Methods:A total of 267 cases with acute lumbar disc herniation (in two practices and four clinics) and 197 control subjects were studied. Data were gathered in a structured personal interview and analysed using logistic regression to control for age, region, nationality, and diseases affecting the lumbar spine. Cases without knowledge about osteochondrosis/spondylosis (n=42) were excluded from analysis. Risk factors were examined separately for those cases with (n=131) and without (n=94) radiographically diagnosed concomitant osteochondrosis or spondylosis.

Results:There was a statistically significant positive association between extreme forward bending and lumbar disc herniation with, as well as without concomitant osteochondrosis/spondylosis. There was a statistically significant relation between cumulative exposure to weight lifting or carrying and lumbar disc herniation with, but not without, concomitant osteochondrosis/spondylosis. Cases with disc herniation reported time pressure at work as well as psychic strain through contact with clients more frequently than control subjects.

Conclusions:Further larger studies are needed to verify the concept of distinct aetiologies of lumbar disc herniation in relatively younger persons with otherwise normal discs and of disc herniation in relatively older persons with structurally damaged discs.
Healthy worker effect and changes in respiratory symptoms and lung function in hairdressing apprentices
Authors: Iwatsubo Y , Matrat M , Brochard P , Ameille J , Choudat D , Conso F , Coulondre D , Garnier R , Hubert C , Lauzier F , Romano M C , Pairon J C
Published: October 2003

Aims:To compare the prevalence and incidence of respiratory symptoms and lung function values between hairdressing apprentices and office apprentices.

Methods:A total of 322 hairdressing apprentices and 277 office apprentices (controls) were studied. Two cross sectional surveys were conducted in 1994 and 1996/97 with longitudinal follow up for a subgroup of apprentices (191 hairdressing apprentices and 189 office apprentices).

Results:In the initial phase, the prevalence of respiratory symptoms was significantly lower among hairdressing apprentices than among office apprentices. Lung function test results showed significantly higher values for hairdressing apprentices. Non-specific bronchial reactivity was similar in the two groups. In the final phase, results for respiratory symptoms were similar. The incidence of respiratory symptoms was not significantly different between hairdressing apprentices and office apprentices. Subjects who dropped out had lower values for FVC and FEV1in the initial phase than those who completed the final phase. There was a significant deterioration of FEV1and FEF25–75%in hairdressing apprentices compared to office apprentices. There was a link between atopy and the incidence of most of the respiratory symptoms (day/night cough, wheezing, dyspnoea, mucosal hyperresponsiveness) and between smoking and the incidence of bronchial hyperreactivity. There was no significant correlation between change in lung function tests and specific hairdressing activities reported at the end of the apprenticeship or with environmental working conditions in hairdressing salons.

Conclusions:Although a healthy worker effect can be suspected, results showed a significant deterioration of baseline values of lung function tests in the hairdressing apprentice group. However, no clear link was shown between change in lung function tests and specific parameters of occupational activities.
Effects of a home exercise programme on shoulder pain and functional status in construction workers
Authors: Ludewig P M , Borstad J D
Published: October 2003

Background:Repetitive or sustained elevated shoulder postures have been identified as a significant risk factor for occupationally related shoulder musculoskeletal disorders. Construction workers exposed to routine overhead work have high rates of shoulder pain that frequently progresses to functional loss and disability. Exercise interventions have potential for slowing this progression.

Aims:To evaluate a therapeutic exercise programme intended to reduce pain and improve shoulder function.

Methods:Construction worker volunteers were screened by history and clinical examination to test for inclusion/exclusion criteria consistent with shoulder pain and impingement syndrome. Sixty seven male symptomatic workers (mean age 49) were randomised into a treatment intervention group (n = 34) and a control group (n = 33); asymptomatic subjects (n = 25) participated as an additional control group. Subjects in the intervention group were instructed in a standardised eight week home exercise programme of five shoulder stretching and strengthening exercises. Subjects in the control groups received no intervention. Subjects returned after 8–12 weeks for follow up testing.

Results:The intervention group showed significantly greater improvements in the Shoulder Rating Questionnaire (SRQ) score and shoulder satisfaction score than the control groups. Average post-test SRQ scores for the exercise group remained below levels for asymptomatic workers. Intervention subjects also reported significantly greater reductions in pain and disability than controls.

Conclusions:Results suggest a home exercise programme can be effective in reducing symptoms and improving function in construction workers with shoulder pain.
Respiratory status in dairy farmers in France; cross sectional and longitudinal analyses
Authors: Chaudemanche H , Monnet E , Westeel V , Pernet D , Dubiez A , Perrin C , Laplante J-J , Depierre A , Dalphin J-C
Published: October 2003

Aims:To compare respiratory status in dairy farmers with that of non-farming controls.

Methods:Longitudinal study in the Doubs (France). From a cohort constituted in 1994 (T1), 215 (81.1%) dairy farmers and 110 (73.8%) controls were reevaluated in 1999 (T2). The protocol comprised a medical and occupational questionnaire, spirometric tests at both evaluations, allergological tests at T1, and a non-invasive measure of blood oxygen saturation (Spo2) at T2.

Results:In 1999 analyses, the prevalence of chronic bronchitis was higher (p = 0.013), and FEV1/VC (p < 0.025) and Spo2(−0.7%, p < 0.01) lower in dairy farmers than in controls. In a multiple linear regression model, farming, age, and smoking were significantly and inversely correlated with Spo2. In the whole population, the mean annual decline in FEV1and FEV1/VC was −13.4 ml and −0.30%, respectively. Farming was associated with an accelerated decline in FEV1/VC (p < 0.025) after adjustment for covariates. No relation between allergy and respiratory function changes was observed, except for FEF25–75.

Conclusions:This prospective study shows that dairy farming is associated with an excess of chronic bronchitis, with a moderate degree of bronchial obstruction and a mild decrease in Spo2.
Lung function decline in laboratory animal workers: the role of sensitisation and exposure
Authors: Portengen L , Hollander A , Doekes G , de Meer G , Heederik D
Published: October 2003

Background:Little is known about the relation between allergic sensitisation and subsequent long term lung function changes in working populations exposed to sensitising agents.

Aims:To investigate whether exposure and work related sensitisation to laboratory animals are associated with lung function decline.

Methods:The relation between exposure and sensitisation to laboratory animal allergens and changes in lung function was investigated in a longitudinal study (median follow up 2.0 years) among 319 laboratory animal workers. Subjects who had been working with laboratory animals for less than 4 years (n = 102) were analysed separately, since an earlier cross sectional analysis had suggested a strong healthy worker effect in more experienced workers.

Results:In multiple regression analyses both sensitisation and exposure appeared to contribute independently to lung function decline in subjects who had been working with laboratory animals for less than 4 years, adjusting for gender, age, smoking, and atopy. Lung function decline was most pronounced in sensitised subjects who continued to be in contact with the animals to which they were sensitised, with estimated average excess declines in FEV1, FVC, and MMEF of 83 ml/y (p < 0.05), 148 ml/y (p < 0.01), and 7 ml/s/y (p = 0.9).

Conclusions:We conclude that exposure to laboratory animals is a significant risk factor for accelerated lung function decline, and that sensitised workers are especially at risk.
NO2, as a marker of air pollution, and recurrent wheezing in children: a nested case-control study within the BAMSE birth cohort
Authors: Emenius G , Pershagen G , Berglind N , Kwon H-J , Lewné M , Nordvall S L , Wickman M
Published: October 2003

Aims:To investigate the association between air pollution, including with NO2, and recurrent wheezing during the first two years of life.

Methods:A birth cohort (BAMSE) comprised 4089 children, for whom information on exposures, symptoms, and diseases was available from parental questionnaires at ages 2 months, and 1 and 2 years. NO2was measured during four weeks in and outside the dwellings of children with recurrent wheezing and two age matched controls, in a nested case-control study (540 children).

Results:Conditional logistic regression showed an OR of 1.60 (95% CI 0.78 to 3.26) among children in the highest quartile of outdoor NO2exposure in relation to those in the lowest quartile, adjusted for potential confounders. The corresponding OR for indoor NO2was 1.51 (95% CI 0.81 to 2.82). An interaction with environmental tobacco smoke (ETS) was indicated with an OR of 3.10 (95% CI 1.32 to 7.30) among children exposed to the highest quartile of indoor NO2and ETS. The association between NO2and recurrent wheezing appeared stronger in children who did not fulfil the criteria for recurrent wheezing until their second year.

Conclusions:Although the odds of increased recurrent wheezing are not statistically significantly different from one, results suggest that exposure to air pollution including NO2, particularly in combination with exposure to ETS, increases the risk of recurrent wheezing in children.
Primary osteoarthritis and occupations: a national cross sectional survey of 10 412 symptomatic patients
Authors: Rossignol M , Leclerc A , Hilliquin P , Allaert F A , Rozenberg S , Valat J-P , Avouac B , Coste P , Savarieau B , Fautrel B
Published: October 2003

Aims:To describe the age standardised prevalence of symptomatic osteoarthritis (OA) in a nationwide cross sectional survey of 10 412 patients in France, and their functional and work limitations.

Methods:Cases in the survey were compared with their expected counterpart by age, gender, and occupational groupings using data from the 1998 French National Survey on Health Impairment and Disability.

Results:Women represented 66.2% of the sample; mean age was 66.2 years. One third of patients had OA of the knee, 16% of the hip, and 12% of the hand; a third had multiple joint OA. Peak prevalence of symptomatic OA was in the 60–69 year category in women and in the 70–79 year category in men. Agricultural workers showed a significant excess prevalence of OA, with an observed to expected (O/E) ratio of 1.7 in women and 2.3 in men. Linear trends in prevalences between white collar, “mixed” collar, and blue collar workers were also significant, with odds ratios respectively of 1.0, 2.9, and 2.6 in women and 1.0, 1.2, and 1.7 in men. Specific excess prevalence was found in women among housekeepers (O/E 4.4), and in men among unskilled labour workers (O/E 10.3) and truck drivers (O/E 6.7). Total work disability was highest among blue collar workers and partial disability among agricultural workers.

Conclusion:Results contribute to the mounting evidence that OA is potentially aetiologically linked to occupation in a sizeable segment of the population and that OA can no longer be considered an inevitable disease of ageing.
Does psychological distress influence reporting of demands and control at work?
Authors: Waldenström K , Lundberg I , Waldenström M , Härenstam A ,   MOA Research Group
Published: October 2003

Aims:To investigate whether self reporting of psychological demands and control at work is as valid for psychologically distressed subjects as for subjects with psychological wellbeing.

Method:Self reported demands and control (according to the model of Karasek) were compared to expert assessments through direct observations of each subject’s work conditions concerning time pressure, hindrances, qualification for work tasks, and possibility of having influence. The comparison was made between respondents reporting and not reporting psychological distress as measured by the general health questionnaire with 12 questions (GHQ-12). The sample consisted of 203 men and women in 85 occupations.

Result:No systematic differences between self reported and externally assessed working conditions for respondents reporting different levels of psychological distress were found.

Conclusion:Over-reporting of work demands or under-reporting of work control is unlikely at the levels of psychological distress studied.
Repeated daily exposure to 2 ppm nitrogen dioxide upregulates the expression of IL-5, IL-10, IL-13, and ICAM-1 in the bronchial epithelium of healthy human airways
Authors: Pathmanathan S , Krishna M T , Blomberg A , Helleday R , Kelly F J , Sandström T , Holgate S T , Wilson S J , Frew A J
Published: October 2003

Background:Repeated daily exposure of healthy human subjects to NO2induces an acute airway inflammatory response characterised by neutrophil influx in the bronchial mucosa

Aims:To assess the expression of NF-κB, cytokines, and ICAM-1 in the bronchial epithelium.

Methods:Twelve healthy, young non-smoking volunteers were exposed to 2 ppm of NO2/filtered air (four hours/day) for four successive days on separate occasions. Fibreoptic bronchoscopy was performed one hour after air and final NO2exposures. Bronchial biopsy specimens were immunostained for NF-κB, TNF-α, eotaxin, Gro-α, GM-CSF, IL-5, -6, -8, -10, -13, and ICAM-1 and their expression was quantified using computerised image analysis.

Results:Expression of IL-5, IL-10, IL-13, and ICAM-1 increased following NO2exposure.

Conclusion:Upregulation of the Th2 cytokines suggests that repeated exposure to NO2has the potential to exert a “pro-allergic” effect on the bronchial epithelium. Upregulation of ICAM-1 highlights an underlying mechanism for leucocyte influx, and could also explain the predisposition to respiratory tract viral infections following NO2exposure since ICAM-1 is a major receptor for rhino and respiratory syncytial viruses.
The impact of a week of simulated night work on sleep, circadian phase, and performance
Authors: Lamond N , Dorrian J , Roach G D , McCulloch K , Holmes A L , Burgess H J , Fletcher A , Dawson D
Published: October 2003

Aims:To investigate factors that may contribute to performance adaptation during permanent night work.

Methods:Fifteen healthy subjects participated in an adaptation and baseline night sleep, directly followed by seven simulated eight-hour night shifts (2300 to 0700 hours). At the end of each shift they were taken outside and exposed to natural light for 20 minutes. They then slept from approximately 0800 hours until they naturally awoke.

Results:There was a significant increase in mean performance on a visual psychomotor vigilance task across the week. Daytime sleep quality and quantity were not negatively affected. Total sleep time (TST) for each of the daytime sleeps was reduced, resulting in an average cumulative sleep debt of 3.53 hours prior to the final night shift. TST for each of the daytime sleep periods did not significantly differ from the baseline night, nor did TST significantly vary across the week. There was a significant decrease in wake time after sleep onset and sleep onset latency across the week; sleep efficiency showed a trend towards greater efficiency across the consecutive daytime sleeps. Hours of wakefulness prior to each simulated night shift significantly varied across the week. The melatonin profile significantly shifted across the week.

Conclusions:Results suggest that under optimal conditions, the sleep debt that accumulates during consecutive night shifts is relatively small and does not exacerbate decrements in night-time performance resulting from other factors. When sleep loss is minimised, adaptation of performance during consecutive night shifts can occur in conjunction with circadian adaptation.
Does computer use pose an occupational hazard for forearm pain; from the NUDATA study
Authors: Kryger A I , Andersen J H , Lassen C F , Brandt L P A , Vilstrup I , Overgaard E , Thomsen J F , Mikkelsen S
Published: October 2003

Aims:To determine the occurrence of pain conditions and disorders in the forearm and to evaluate risk factors for forearm pain in a cohort of computer workers.

Methods:A total of 6943 participants with a wide range of computer use and work tasks were studied. At baseline and at one year follow up participants completed a questionnaire. Participants with relevant forearm symptoms were offered a clinical examination. Symptom cases and clinical cases were defined on the basis of self reported pain score and palpation tenderness in the muscles of the forearm.

Results:The seven days prevalence of moderate to severe forearm pain was 4.3%. Sixteen of 296 symptom cases met criteria for being a clinical forearm case, and 12 had signs of potential nerve entrapment. One year incidence of reported symptom cases was 1.3%; no subjects developed new signs of nerve entrapment. Increased risk of new forearm pain was associated with use of a mouse device for more than 30 hours per week, and with keyboard use more than 15 hours per week. High job demands and time pressure at baseline were risk factors for onset of forearm pain; women had a twofold increased risk of developing forearm pain. Self reported ergonomic workplace factors at baseline did not predict future forearm pain.

Conclusion:Intensive use of a mouse device, and to a lesser extent keyboard usage, were the main risk factors for forearm pain. The occurrence of clinical disorders was low, suggesting that computer use is not commonly associated with any severe occupational hazard to the forearm.
The effect of sulphurous air pollutant exposures on symptoms, lung function, exhaled nitric oxide, and nasal epithelial lining fluid antioxidant concentrations in normal and asthmatic adults
Authors: Tunnicliffe W S , Harrison R M , Kelly F J , Dunster C , Ayres J G
Published: October 2003

Aims:To explore the effects in normal and asthmatic adults of exposure to 200 ppb sulphur dioxide (SO2) and 200 μg/m3and 2000 μg/m3aerosols of ammonium bisulphate (AB) and sulphuric acid (SA) (MMD 0.3 μm).

Methods:Exposures were placebo controlled, for one hour at rest, double blind in random order. ΔFEV1was the primary outcome; secondary outcomes included symptoms, ventilation, exhaled nitric oxide (NO) concentrations, and nasal lavage fluid ascorbic (AA) and uric acid (UA) concentrations.

Results:There were no significant changes in spirometry or symptoms with any exposure in either group. SO2exposure was associated with an increased respiratory rate relative to air exposure in the asthmatic group (SO2: 958.9 breaths/hour; air: 906.8 breaths/hour) but the mean volume breathed did not differ significantly (SO2: 318.8 litres; air: 311.4 litres). AB exposures were associated with a significant rise in [NO] in the asthmatic (+1.51 ppb, and +1.39 ppb), but not in the normal group. Mean pre- and post-exposure [AA] tended to be higher in the normal than in the asthmatic group. Within each group, [AA] did not change significantly with any exposure. Post-exposure [UA] were greater than pre-exposure concentrations for all exposures, significantly so in the normal group for all exposures except SO2. There were no significant differences in the mean change in [UA] for any exposure relative to air.

Conclusions:The pollutant exposure concentrations employed in this study were generally much greater than ambient. It is unlikely that short lived exposures at lower concentrations would show significant effects, but effects of longer term lower concentration exposures cannot be ruled out.
Complexification and Hypercomplexification of Manifolds with a Linear Connection
Authors: Bielawski Roger
Published: October 2003

We give a simple interpretation of the adapted complex structure of Lempert–Szöke and Guillemin–Stenzel: it is given by a polar decomposition of the complexified manifold. We then give a twistorial construction of an SO(3)-invariant hypercomplex structure on a neighbourhood of X in TTX, where X is a real-analytic manifold equipped with a linear connection. We show that the Nahm equations arise naturally in this context: for a connection with zero curvature and arbitrary torsion, the real sections of the twistor space can be obtained by solving Nahm's equations in the Lie algebra of certain vector fields. Finally, we show that, if we start with a metric connection, then our construction yields an SO(3)-invariant hyperkähler metric.
Orbifold Cohomology as Periodic Cyclic Homology
Authors: Baranovsky Vladimir
Published: October 2003

It is known from the work of Feigin–Tsygan, Weibel and Keller that the cohomology groups of a smooth complex variety X can be recovered from (roughly speaking) its derived category of coherent sheaves. In this paper we show that for a finite group G acting on X the same procedure applied to G-equivariant sheaves gives the orbifold cohomology of X/G.

As an application, in some cases we are able to obtain simple proofs of an additive isomorphism between the orbifold cohomology of X/G and the usual cohomology of its crepant resolution (the equality of Euler and Hodge numbers was obtained earlier by various authors). We also state some conjectures on the product structures, as well as the singular case; and a connection with a recent work by Kawamata.
Local Simple Connectedness of Resolutions of Log-Terminal Singularities
Authors: Takayama Shigeharu
Published: October 2003

We study fundamental groups related with log-terminal singularities, and show that fundamental groups are preserved by a resolution of singularities. As corollaries, we show that fundamental groups are invariant under various fundamental operations in the Minimal Model Program, for example, by contractions of extremal rays, by flips, by pluricanonical morphisms of minimal varieties of general type.
Singularities on the 2-Dimensional Moduli Spaces of Stable Sheaves on K3 Surfaces
Authors: Onishi Nobuaki , Yoshioka Kōta
Published: October 2003

We consider the singuralities of 2-dimensional moduli spaces of semi-stable sheaves on k3 surfaces. We show that the moduli space is normal, in particular the siguralities are rational double points. We also describe the exceptional locus on the resolution in terms of exceptional sheaves.
On q-Basic Multiple Gamma Functions
Authors: Kurokawa Nobushige , Wakayama Masato
Published: October 2003

We define a q-analogue of the basic multiple gamma function [Formula: see text] introduced in [17] which differs from the one defined by Barnes [1] via the zeta regularized product. We call it a q-basic multiple gamma function. Using this q-basic multiple Gamma function we introduce a q-analogue of the multiple sine function of order m + 1. We study properties of such functions from the periodicity, differential-difference equations and duplication formulas, etc. points of view.
Phenomenology of Low-Scale Supersymmetry Breaking Models
Authors: Navarro Ignacio
Published: October 2003

In this review we consider the distinctive phenomenology of supersymmetric models in which the scale of SUSY breaking is very low, [Formula: see text], focusing on the Higgs sector and the process of electroweak breaking. Using an effective Lagrangian description of the interactions between the observable fields and the SUSY breaking sector, it is shown how the conventional MSSM picture can be substantially modified. For instance, the Higgs potential has non-negligible SUSY breaking quartic couplings that can modify completely the pattern of electroweak breaking and the Higgs spectrum with respect to that of the conventional MSSM-like models.
Observation of Void Probability Scaling of Proton Emission in High Energy Nucleus–Nucleus Collisions
Authors: Ghosh Dipak , Deb Argha , Sahoo Swarup Ranjan , Haldar Prabir Kumar , Bhattacharyya Swarnapratim
Published: October 2003

In this paper the study of gap probability of protons has been carried out with 28 Si–AgBr interaction at 14.5 A GeV in emission angle space. The study reveals the scaling behaviour of the void probability which hints towards the outer space–inner space connection. This study also confirms the validity of the linked pair approximation for the N-particle cumulant correlation functions in case of protons.
Quark Clustering and Chiral Symmetry Breaking in Nuclear Matter
Authors: Battistel O. A. , Krein G.
Published: October 2003

Chiral symmetry breaking at finite baryon density is usually discussed in the context of quark matter, i.e. a system of deconfined quarks. Many systems like stable nuclei and neutron stars however have quarks confined within nucleons. In this paper we construct a Fermi sea of three-quark nucleon clusters and investigate the change of the quark condensate as a function of baryon density. We study the effect of quark clustering on the in-medium quark condensate and compare results with the traditional approach of modeling hadronic matter in terms of a Fermi sea of deconfined quarks.
BFT Hamiltonian Embedding of Massive Theory with One- and Two-Form Gauge Fields
Authors: Kim Yong-Wan , Kim Seung-Kook , Park Young-Jai
Published: October 2003

Without resorting to the symplectic condition, we rigorously study the constraint structure of the topologically massive theory with one- and two-form fields in the framework of Batalin–Fradkin–Tyutin Hamiltonian embedding procedure. Through this full analysis we obtain a new type of Wess–Jumino action with novel symmetry, which is originated from the topological coupling term, as well as the Stückelberg action related to the explicit gauge breaking mass terms from the original theory.
A New Approach Treating Constrained Systems Based on the Consistency Condition of Constraints
Authors: Long Zheng-Wen , Liu Bo
Published: October 2003

A new approach treating constrained systems based on the consistency condition of constraints is proposed in this paper. This method is simpler and more rigorous in mathematics. It is not necessary to introduce the concepts of weakly equal, strongly equal, Dirac brackets and Dirac conjecture. The procedure of our method is demonstrated by using Cawley's counterexample to Dirac's conjecture.
Massive Quantum Vortex Excitations in a Pure Gauge Abelian Theory in 2 + 1D
Authors: Marino E. C. , Takakura Flávio I.
Published: October 2003

We introduce and study a pure gauge Abelian theory in 2 + 1D in which massive quantum vortex states do exist in the spectrum of excitations. This theory can be mapped in a three-dimensional gas of point particles with a logarithmic interaction, in the grand-canonical ensemble. We claim that this theory is the 2 + 1D analog of the sine–Gordon, the massive vortices being the counterparts of sine–Gordon solitons. We show that a symmetry breaking, order parameter, similar to the vacuum expectation value of a Higgs field does exist.
BRST Quantization of the Proca Model Based on the BFT and the BFV Formalism
Authors: Kim Yong-Wan , Park Mu-In , Park Young-Jai , Yoon Sean J.
Published: October 2003

The BRST quantization of the Abelian Proca model is performed using the Batalin–Fradkin–Tyutin and the Batalin-Fradkin-Vilkovisky formalism. First, the BFT Hamiltonian method is applied in order to systematically convert a second class constraint system of the model into an effectively first class one by introducing new fields. In finding the involutive Hamiltonian we adopt a new approach which is simpler than the usual one. We also show that in our model the Dirac brackets of the phase space variables in the original second class constraint system are exactly the same as the Poisson brackets of the corresponding modified fields in the extended phase space due to the linear character of the constraints comparing the Dirac or Faddeev–Jackiw formalisms. Then, according to the BFV formalism we obtain that the desired resulting Lagrangian preserving BRST symmetry in the standard local gauge fixing procedure naturally includes the Stückelberg scalar related to the explicit gauge symmetry breaking effect due to the presence of the mass term. We also analyze the nonstandard nonlocal gauge fixing procedure.
New Semiclassical Non-Abelian Vertex Operators for Chiral and Nonchiral WZW Theory
Authors: Halpern M. B. , Obers N. A.
Published: October 2003

We supplement the discussion of Moore and Reshetikhin and others by finding new semiclassical non-Abelian vertex operators for the chiral, antichiral and nonchiral primary fields of WZW theory. These new non-Abelian vertex operators are the natural generalization of the familiar Abelian vertex operators: they involve only the representation matrices of Lie g, the currents of affine (g × g) and certain chiral and antichiral zero modes, and they reduce to the Abelian vertex operators in the limit of Abelian algebras. Using the new constructions, we also discuss semiclassical operator product expansions, braid relations and relations to the known form of the semiclassical affine-Sugawara conformal blocks.
Sp(4, R)/GL(2, R) Matrix Structure of Geodesic Solutions for Einstein–Maxwell–Dilaton–Axion Theory
Authors: Kechkin Oleg , Yurova Maria
Published: October 2003

The Sp (4, R)/ GL (2, R) matrix operator defining the family of isotropic geodesic lines in the target space of the stationary D = 4 Einstein–Maxwell–dilaton–axion theory is constructed. This operator is used to derive a class of solutions describing a system of point centers with nontrivial values of mass, parameter NUT, as well as electric, magnetic, dilaton and axion charges. It is shown that this class contains the Majumdar–Papapetrou-like solutions and also the solutions for massless naked singularities.
Consistent Interactions in Terms of the Generalized Fields Method
Authors: Dayi Ömer F.
Published: October 2003

The interactions which preserve the structure of the gauge interactions of the free theory are introduced in terms of the generalized fields method for solving the Batalin–Vilkovisky master equation. It is shown that by virtue of this method the solution of the descent equations resulting from the cohomological analysis is provided straightforwardly. The general scheme is illustrated by applying it to the spin 1 gauge field in three and four dimensions, to free BF theory in 2D, and to the antisymmetric tensor field in any dimension. It is shown that it reproduces the results obtained by cohomological techniques.
The Path Integral for (1 + 1)-Dimensional QCD
Authors: Jahn O. , Kraus T. , Seeger M.
Published: October 2003

We derive a path integral expression for the transition amplitude in (1 + 1)-dimensional QCD starting from canonically quantized QCD. Gauge fixing after quantization1 leads to a formulation in terms of gauge invariant but curvilinear variables. Remainders of the curved space are Jacobians, an effective potential, and sign factors just as for the problem of a particle in a box. Based on this result we derive a Faddeev–Popov-like expression for the transition amplitude avoiding standard infinities that are caused by integrations over gauge equivalent configurations.
Non-Abelian Gauge Symmetry in the Causal Epstein–Glaser Approach
Authors: Hurth Tobias
Published: October 2003

Non-Abelian gauge symmetry in (3 + 1)-dimensional space–time is analyzed in the causal Epstein–Glaser framework. In this formalism, the technical details concerning the well-known UV and IR problem in quantum field theory are separated and reduced to well-defined problems, namely the causal splitting and the adiabatic switching of operator-valued distributions. Non-Abelian gauge invariance in perturbation theory is completely discussed in the well-defined Fock space of free asymptotic fields. The LSZ formalism is not used in this construction. The linear operator condition of asymptotic gauge invariance is sufficient for the unitarity of the S matrix in the physical subspace and the usual Slavnov–Taylor identities.

We explicitly derive the most general specific coupling compatible with this condition. By analyzing only tree graphs in the second order of perturbation theory we show that the well-known Yang–Mills couplings with anticommuting ghosts are the only ones which are compatible with asymptotic gauge invariance. The required generalizations for linear gauges are given.