bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Doping on the Electrochemical and Electrical Properties of Poly(2,5-di(2-thienyl)pyrrole)
Authors: Brillas Enric , Carrasco José , Oliver Ramon , Estrany Francesc , Ruiz Víctor
Published: July 2002

The electropolymerization of 2,5-di(2-(thienyl)pyrrole) (SNS) on a Pt electrode from ethanolic solution with LiClO4 or LiCl as electrolyte has been studied by cyclic voltammetry (CV) and chronoamperometry (CA). In both media, a quasi-reversible process has been indicated by CV, reversing the scan at low oxidation potentials. Under these conditions, reducible positive charges formed in both oxidized polymers are compensated by the entrance of anions from solution. Elemental analysis reveals that polymers generated at a low oxidation potential by CA contain a 21.03% (w/w) of ClO4- or a 9.56% (w/w) of Cl-. The poly(SNS) doped with Cl- presents higher proportion of reducible positive charges, higher polymerization charge and lower productivity. A much higher electrical conductivity, however, has been found for the poly(SNS) doped with ClO4-. Both polymers are soluble in DMSO, acetone and methanol. The dimer, trimer, tetramer and pentamer have been detected as soluble and neutral linear oligomers by mass spectrometry-fast atom bombardment. The analysis of polymers by infrared spectroscopy confirms the predominant formation of linear molecules with α-α linkages between monomeric units. A condensation mechanism involving one-electron oxidation of all electrogenerated linear and neutral polymeric chains is proposed to explain the SNS electropolymerization.
Correlation of PCB Transformation by Plant Tissue Cultures with Their Morphology and Peroxidase Activity Changes
Authors: Kučerová Petra , Macková Martina , Poláchová Ludmila , Burkhard Jiří , Demnerová Kateřina , Pazlarová Jarmila , Macek Tomáš
Published: July 2002

The ability of plant cells cultivated in vitro to metabolize polychlorinated biphenyls (PCBs) was correlated with the morphology of the cultures tested as models for phytoremediation studies. More differentiated cultures showed generally higher transformation capacity. The ability of plant cells to transform PCBs is connected to their viability in the presence of PCBs and their behaviour can be positively correlated with the production of intracellular and extracellular peroxidases. The cultures with high PCB-transforming activity proved to exhibit high peroxidase activity in the presence of PCBs while those with low ability to metabolize PCB showed a decrease of the enzyme activity in the presence of PCBs. Experiments with propylgallate were used to distinguish the ratio of involvement of peroxidases in PCB metabolism.
Gold-Plated Carbon Paste Electrodes for Anodic Stripping Determination of Arsenic
Authors: Chadim Petr , Švancara Ivan , Pihlar Boris , Vytřas Karel
Published: July 2002

The applications of gold-plated carbon paste electrodes in anodic stripping voltammetry have been studied in an effort to develop a simple and effective method for the determination of arsenic in water samples. The investigations performed included the choice of supporting electrolyte composition, the optimisation of important experimental parameters, search for appropriate procedure to reduce As(V) to As(III), and some tests of practical applicability of the method, including interference studies. Under optimised conditions, the signal of As was linear within 5-50 μg l-1 with a detection limit of about 1 μg l-1 As (deposition time 10 min). Common elements or ions did not interfere except for Cu(II). The analytical performance of the method has been tested in recovery measurements with model solutions.
Selective Cleavage of O-(Dimethoxytrityl) Protecting Group with Sodium Periodate
Authors: Rejman Dominik , Králíková Šárka , Točík Zdeněk , Liboska Radek , Rosenberg Ivan
Published: July 2002

Sodium periodate in aqueous organic solvents selectively removes, under mild reaction conditions, the O-(dimethoxytrityl) protecting group. Selectivity of the cleavage was studied using the nucleoside derivatives protected by various types of groups commonly used in nucleoside and nucleotide chemistry.
A critique of the expression of paediatric body composition data
Authors: Wells J C K
Published: July 2002

There is increasing interest in body composition in paediatric research, as distinct from growth and nutritional status, as almost all diseases have adverse effects on either fatness or the fat-free mass. However, the approaches used to assess growth and nutritional status are not appropriate for separate evaluations of body fatness and lean mass. Traditional measurements such as body mass index and skinfold thickness do not measure fat in accurate quantitative terms. Various techniques have been used in recent years which divide body weight into fat mass and fat-free mass; however, the data tend not to be appropriately expressed. Body fatness is generally expressed as a percentage of weight, while fat-free mass typically remains unadjusted for size. A more appropriate approach is to normalise both body fatness and fat-free mass for height. This recommendation is relevant both to studies comparing patients with controls and to the expression of new reference data on body composition which are needed to allow informative comparisons. The same approach is appropriate for the classification of childhood obesity.
Does physical activity reduce the risk of developing peptic ulcers?
Authors: Cheng Yiling , Macera Caroline A , Davis Dorothy R , Blair Steven N
Published: July 2002

Background—AlthoughHelicobacter pylorihas been identified as a major cause of chronic gastritis, not all infected patients develop ulcers, suggesting that other factors such as lifestyle may be critical to the development of ulcer disease.

Aim—To investigate the role physical activity may play in the incidence of peptic ulcer disease.

Methods—The subjects were men (8529) and women (2884) who attended the Cooper Clinic in Dallas between 1970 and 1990. The presence of gastric or duodenal ulcer disease diagnosed by a doctor was determined from a mail survey in 1990. Subjects were classified into three physical activity groups according to information provided at the baseline clinic visit (before 1990): active, those who walked or ran 10 miles or more a week; moderately active, those who walked or ran less than 10 miles a week or did another regular activity; the referent group consisting of those who reported no regular physical activity.

Results—With the use of gender specific proportional hazards regression models that could be adjusted for age, smoking, alcohol use, body mass index, and self reported tension, active men were found to have a significant reduction in risk for duodenal ulcers (relative hazard (95% confidence interval) for the active group was 0.38 (0.15 to 0.94) and 0.54 (0.30 to 0.96) for the moderately active group). No association was found between physical activity and gastric ulcers for men or for either type of ulcer for women.

Conclusions—Physical activity may provide a non-pharmacological method of reducing the incidence of duodenal ulcers among men.
Effectiveness of headgear in a pilot study of under 15 rugby union football
Authors: McIntosh A S , McCrory P
Published: July 2002

Objective—To determine whether protective headgear reduced the incidence of concussion in a pilot study of under 15 rugby union.

Methods—Sixteen under 15 rugby union teams were recruited from three interschool competitions in metropolitan Sydney and the adjacent country region. A prospective study was undertaken over a single competitive season. The study had two arms: a headgear arm and a control arm. Headgear wearing rates and injury data were reported to the investigators and verified using spot checks.

Results—A total of 294 players participated in the study. There were 1179 player exposures with headgear and 357 without headgear. In the study time frame, there were nine incidences of concussion; seven of the players involved wore headgear and two did not. There was no significant difference between concussion rates between the two study arms.

Conclusions—Although there is some controversy about the desirability of wearing protective headgear in football, this pilot study strongly suggests that current headgear does not provide significant protection against concussion in rugby union at a junior level.
Nirschl tennis elbow release with or without drilling
Authors: Khashaba A
Published: July 2002

Nirschl release appears to be a very successful technique for surgically suitable cases of tennis elbow. However, although the drilling or decortication aspect of the procedure was thought to be of benefit to the immediate outcome, this has not actually been confirmed. This randomised double blind comparative prospective trial shows that drilling confers no benefit and actually causes more pain, stiffness, and wound bleeding than not drilling.
A reduction in training volume and intensity for 21 days does not impair performance in cyclists
Authors: Rietjens G J W M , Keizer H A , Kuipers H , Saris W H M
Published: July 2002

Objectives—(a) To investigate the effects of reduced training on physical condition and performance in well trained cyclists; (b) to study whether an intermittent exercise programme would maintain physiological training adaptations more effectively than a continuous exercise programme during a period of reduced training.

Methods—Twelve male cyclists participated in a 21 day training programme and were divided into two training groups. One group (age 25.3 (7) years; weight 73.3 (5.7) kg; Vo2max58.6 (4.5) ml/kg/min; means (SD)) underwent a continuous endurance exercise training programme (CT) whereas the second group (age 22.8 (3.5) years; weight 74.1 (7.0) kg; Vo2max59.7 (6.7) ml/kg/min) followed an intermittent endurance exercise training programme (IT). During this reduced training period, both groups trained for two hours a day, three days a week.

Results—Neither group showed changes in maximal workload (Wmax) (4.6 (0.5)v4.8 (0.5) W/kg and 4.6 (0.5)v4.7 (0.6) W/kg for the CT and IT group respectively) and Vo2max(58.6 (4.5)v60.1 (5.8) ml/kg/min and 59.7 (6.7)v58.8 (7.5) ml/kg/min for the CT and IT group respectively). During the submaximal steady state exercise test, substrate use and heart rate remained unchanged after reduced training.

Conclusions—These results indicate that well trained cyclists who reduce training intensity and volume for 21 days can maintain physiological adaptations, as measured during submaximal and maximal exercise. An intermittent training regimen has no advantage over a continuous training regimen during a detraining period.
Randomised controlled trial of prophylactic etamsylate: follow up at 2 years of age
Authors: Elbourne D , Ayers S , Dellagrammaticas H , Johnson A , Leloup M , Lenoir-Piat S
Published: July 2002

AIM

To assess the role of etamsylate* in reducing the risk of haemorrhagic brain damage and its consequences.

DESIGN

Follow up of babies recruited into a randomised controlled trial.

METHODS

A total of 334 infants born before 33 weeks gestation in France and Greece were randomly allocated within the first four hours of birth either to receive etamsylate or to act as controls. The principal outcomes in the trial were death or impairment and/or disability at the age of 2 years.

RESULTS

Fifty nine children were lost to follow up. A total of 115 (34%) either died or had some impairment or disability, and 88 (26%) either died or had severe impairment or disability at 2 years of age. These outcomes did not differ significantly between the two randomised groups: relative risks and 95% confidence intervals 1.14 (0.78 to 1.4) and 1.17 (0.82 to 1.68) respectively. The findings were similar for all the prespecified subgroup analyses stratified by key prognostic factors at trial entry: country of birth, gestational age < or ⩾ 29 weeks, inborn or outborn, age < or ⩾  1 hour, and with or without cerebral scan abnormality.

CONCLUSION

These findings do not support the use of etamsylate. Other strategies need to be evaluated for the prevention of mortality and morbidity in these vulnerable infants.

Key messages

The findings from the only published follow up of children from a randomised controlled trial of etamsylate do not support its use when given within the first four hours of birth to infants born before 33 weeks gestation

Centres in Greece and France recruited 334 infants into the trial, and did not find that etamsylate reduced the risk of haemorrhagic brain damage or its consequences in terms of death or impairment and/or disability

Other strategies need to be evaluated for the prevention of mortality and morbidity in these vulnerable infants
Unconscious violinists and the use of analogies in moral argument
Authors: Wiland Eric
Published: July 2002

Analogies are the stuff out of which normative moral philosophy is made. Certainly one of the most famous analogies constructed by a philosopher in order to argue for a specific controversial moral conclusion is the one involving Judith Thomson's unconscious violinist. Reflection upon this analogy is meant to show us that abortion is generally not immoral even if the prenatal have the same moral status as the postnatal. This was and still is a controversial conclusion, and yet the analogy does seem to reveal in a very vivid way what makes abortion a reasonable response to a terrible situation. But Thomson's example has frequently been attacked on all sides for not being truly analogous to abortion. Here I develop a brand new analogy that sheds light on the issue with which Thomson was concerned, while at the same time avoiding most of the more serious objections made to her analogy.
BRCA1 andBRCA2 mutation status and cancer family history of Danish women affected with multifocal or bilateral breast cancer at a young age
Authors: Bergthorsson J T , Ejlertsen B , Olsen J H , Borg A , Nielsen K V , Barkardottir R B , Klausen S , Mouridsen H T , Winther K , Fenger K , Niebuhr A , Harboe T L , Niebuhr E
Published: July 2002

INTRODUCTION

A small fraction of breast cancer is the result of germline mutations in theBRCA1 and BRCA2cancer susceptibility genes. Mutation carriers frequently have a positive family history of breast and ovarian cancer, are often diagnosed at a young age, and may have a higher incidence of double or multiple primary breast tumours than breast cancer patients in general.

OBJECTIVES

To estimate the prevalence and spectrum of BRCA1 andBRCA2 mutations in young Danish patients affected with bilateral or multifocal breast cancer and to determine the relationship of mutation status to family history of cancer.

SUBJECTS

From the files of the Danish Breast Cancer Cooperative Group (DBCG), we selected 119 breast cancer patients diagnosed before the age of 46 years with either bilateral (n=59) or multifocal (n=61) disease.

METHODS

DNA from the subjects was screened for BRCA1 andBRCA2 mutations using single strand conformation analysis (SSCA) and the protein truncation test (PTT). Observed and expected cancer incidence in first degree relatives of the patients was estimated using data from the Danish Cancer Registry.

RESULTS

Twenty four mutation carriers were identified (20%), of whom 13 had aBRCA1 mutation and 11 carried aBRCA2 mutation. Two mutations inBRCA1 were found repeatedly in the material and accounted for seven of the 24 (29%) mutation carriers. The mutation frequency was about equal in patients with bilateral (22%) and multifocal breast cancer (18%). The incidence of breast and ovarian cancer was greatly increased in first degree relatives ofBRCA1 and BRCA2mutation carriers, but to a much lesser degree in relatives of non-carriers. An increased risk of cancer was also noted in brothers of non-carriers.

CONCLUSIONS

A relatively broad spectrum of germline mutations was observed inBRCA1 and BRCA2and most of the mutations are present in other populations. Our results indicate that a diagnosis of bilateral and multifocal breast cancer is predictive of BRCA1 andBRCA2 mutation status, particularly when combined with information on the patients' age at diagnosis and family history of breast/ovarian cancer.
Exposure to silica and silicosis among tin miners in China: exposure-response analyses and risk assessment
Authors: Chen W , Zhuang Z , Attfield M D , Chen B T , Gao Pi , Harrison J C , Fu C , Chen J-Q , Wallace W E
Published: July 2002

OBJECTIVES

To investigate the risk of silicosis among tin miners and to investigate the relation between silicosis and cumulative exposure to dust (Chinese total dust and respirable crystalline silica dust).

METHODS

A cohort study of 3010 miners exposed to silica dust and employed for at least 1 year during 1960–5 in any of four Chinese tin mines was conducted. Historical total dust data from China were used to create a job exposure matrix for facility, job title, and calendar year. The total dust exposure data from China were converted to estimates of exposure to respirable crystalline silica for comparison with findings from other epidemiological studies of silicosis. Each worker's work history was abstracted from the complete employment records in mine files. Diagnoses of silicosis were based on 1986 Chinese pneumoconiosis Roentgen diagnostic criteria, which classified silicosis as stages I-III—similar to an International Labour Organisation (ILO) classification of 1/1 or greater.

RESULTS

There were 1015 (33.7%) miners identified with silicosis, who had a mean age of 48.3 years, with a mean of 21.3 years after first exposure (equivalent to 11.0 net years in a dusty job). Among those who had silicosis, 684 miners (67.4%) developed silicosis after exposure ended (a mean of 3.7 years after). The risk of silicosis was strongly related to cumulative exposure to silica dust and was well fitted by the Weibull distribution, with the risk of silicosis less than 0.1% when the Chinese measure of cumulative exposure to total dust (CTD) was under 10 mg/m3-years (or 0.36 mg/m3-years of respirable crystalline silica), increasing to 68.7% when CTD exposure was 150 mg/m3-years (or 5.4 mg/m3-years of respirable crystalline silica). Latency period was not correlated to the risk of silicosis or cumulative dose of exposure. This study predicts about a 36% cumulative risk of silicosis for a 45 year lifetime exposure to these tin mine dusts at the CTD exposure standard of 2 mg/m3, and a 55% risk at 45 years exposure to the current United States Occupational Safety and Health Administration and Mine Safety and Health Administration standards of 0.1 mg/m3100% respirable crystalline silica dust.

CONCLUSIONS

A clear exposure-response relation was detected for silicosis in Chinese tin miners. The study results were similar to most, but not all, findings from other large scale exposure-response studies.
Erionite bodies and fibres in bronchoalveolar lavage fluid (BALF) of residents from Tuzköy, Cappadocia, Turkey
Authors: Dumortier P , Çoplü L , Broucke I , Emri S , Selcuk T , de Maertelaer V , De Vuyst P , Baris I
Published: July 2002

OBJECTIVES

The high incidence of malignant mesothelioma in some villages of Cappadocia (Turkey) is due to environmental exposure to erionite fibres. The aim was to evaluate the fibre burden in bronchoalveolar lavage fluid (BALF) from inhabitants of an erionite village and compare it with Turkish subjects with or without environmental exposure to tremolite asbestos.

METHODS

Ferruginous bodies (FBs) and fibres were measured and analyzed by light and transmission electron microscopy (TEM) in the BALF of 16 subjects originating from Tuzköy.

RESULTS

FBs were detected in the BALF of 12 subjects, with concentrations above 1 FB/ml in seven of them. Erionite was the central fibre of 95.7% of FBs. Erionite fibres were found in the BALF of all subjects, by TEM, and these fibres were low in Mg, K, and Ca compared with erionite from Tuzköy soil. The mean concentration of erionite fibres in BALF was similar to that of tremolite fibres in Turks with environmental exposure to tremolite. The proportion of fibres longer than 8 μm in BALF represented 35.6% for erionite compared with 14.0% for tremolite. The asbestos fibre concentrations in erionite villagers was not different from that in Turks without environmental exposure to tremolite.

CONCLUSION

Analysis of BALF gives information about fibre retention in populations environmentally exposed to erionite for whom data on fibre burden from lung tissue samples are scarce. This may apply to exposed Turks having emigrated to other countries.
Sickness absence in diabetic employees
Authors: Škerjanc A
Published: July 2002

OBJECTIVES

To compare sickness absence among diabetic and non-diabetic employees.

METHODS

A cross sectional case-control study was conducted in a random sample of 400 diabetic employees 21–50 years old from Ljubljana that compared their sickness absence in the year 1996 with sickness absence of non-diabetic employees matched by sex, age, and occupation. Sickness absence was compared in total and also in subgroups formed by sex, age, occupation, and disability. Non-parametric statistics were used (χ2test, Wilcoxon matched pairs test).

RESULTS

The randomised sample consisted of 61.2% of men (245) and 38.8% of women (155) with a mean age of 42.5 years. Unskilled workers made up 30.2% of employees, and less than 16.4% were highly educated. Among diabetic employees there were 7.0% disabled and among non-diabetic employees 2.0%. The mean frequency of sickness absences of diabetic employees was 0.89 times in the year 1996 (95% confidence interval (95% CI) 0.70 to 1.08), and of non-diabetic employees 0.56 times (95% CI 0.47 to 0.65), p=0.01. The mean total duration of sickness absence of diabetic employees was 31.71 days (95% CI 24.86 to 38.57), of non-diabetic employees 16.57 days (95% CI 11.72 to 21.42), p<0.01. Differences were also found in subgroups but the size of subgroups was not sufficient to detect significant differences.

CONCLUSIONS

The study confirmed that diabetes affects the ability to work. Appropriate work and good control of the disease are important to prevent long term complications.
The EMECAM project: a multicentre study on air pollution and mortality in Spain: combined results for particulates and for sulfur dioxide
Authors: Ballester F , Sáez M , Pérez-Hoyos S , Iñíguez C , Gandarillas A , Tobías A , Bellido J , Taracido M , Arribas F , Daponte A , Alonso E , Cañada A , Guillén-Grima F , Cirera L , Pérez-Boíllos M J , Saurina C , Gómez F , Tenías J M
Published: July 2002

Objective: The EMECAM study is a collaborative effort to evaluate the impact of air pollution on mortality in Spain. In this paper the combined results are presented for the short term effects of particulates and sulfur dioxide on both daily mortality for all and for specific causes.

Methods: The relation between daily mortality for all causes, cardiovascular diseases, and respiratory diseases, and air pollution for particulates (daily concentrations) and SO2(24 and 1 hour concentrations) was assessed in 13 Spanish cities for the period 1990–6. With a standardised method, magnitude of association in each city was estimated by Poisson regression in a generalised additive model. Local estimates were obtained from both single and two pollutant analyses. Lastly, combined estimates for each cause and pollutant were obtained.

Results: For combined results, in single pollutant models a 10 μg/m3increase in the concentration of the mean of the concurrent and one day lag for black smoke was associated with a 0.8% (95% confidence interval (95% CI) 0.4 to 1.1%) increase in total mortality. The estimates for total suspended particles (TSPs) and particulate matter of aerodynamic diameter <10 μm (PM10) and total mortality were slightly lower. The same increase in concentrations of SO2was associated with a 0.5% increase in daily deaths. For groups of specific causes, higher estimations were found, specially for respiratory conditions. Peak concentrations of SO2showed significant associations with the three groups of mortality. When two pollutant analyses were performed, estimates for particulates, specially for black smoke, did not substantially change. The estimates for daily concentrations of SO2were greatly reduced, but, on the contrary, the association with peak concentrations of SO2did not show any change.

Conclusions: There is an association between mortality and pollution through particulates among city populations in Spain. Peak rather than daily concentrations of SO2were related to mortality. Results suggest that populations in Spanish cities are exposed to health risks derived from air pollution.
The effect of reminder calls in reducing non-attendance rates at care of the elderly clinics
Authors: Dockery F , Rajkumar C , Chapman C , Bulpitt C , Nicholl C
Published: July 2002

BACKGROUND

DNA (“did not attend”) at outpatient clinics is an important problem costing the NHS an estimated £266 million annually. The national DNA rate for 1996–1997 for all clinics was 12%. The DNA rate at Hammersmith Hospital for the same year in the care of the elderly specialty was 21%. The aim of this study was to establish why this was so, and to test the efficacy of a reminder call in increasing attendance rates at care of the elderly clinics.

METHODS

23 DNAs from seven clinics were contacted to ascertain the reasons for non-attendance (group I). For seven further clinics, 84 patients were contacted in advance to reconfirm their appointment (group II).

Results

From group II 12 patients were identified who were unaware of their appointment (14%), six of whom agreed to attend; thus six potential DNAs were prevented. Eleven vacant appointments were identified in advance. The unexpected DNA rate was reduced to 5% from a potential 21% as a result of this exercise. The DNA rate for all patients with dementia (both groups) was 44%, whereas the DNA rate for all patients without this diagnosis (both groups) was 16% (p < 0.001).

CONCLUSIONS

A preclinic phone call reminder to elderly patients is feasible, increases attendance rates, and identifies vacant appointments. Patients with dementia are more likely to miss clinic appointments; therefore they and their carers need specific reminders about appointment dates.
Review of the complications and medicolegal implications of vasectomy
Authors: Gingell C , Crosby D , Carroll R
Published: July 2002

The operation of vasectomy is a commonly performed procedure for male sterilisation. It should normally be a straightforward day case procedure undertaken by a competent medical practitioner under local anaesthesia. But how is competence assessed? General practitioners (GPs) have increasingly undertaken minor surgical procedures, and guidance to ensure an appropriate standard of care for patients undergoing such surgery in general practice has been published.1 Vasectomy, however, is not specifically mentioned though problems relating to vasectomy are the main cause of claims against GPs for medical negligence related to minor surgery.2
Management of spontaneous pneumothorax: are British Thoracic Society guidelines being followed?
Authors: Mendis D , El-Shanawany T , Mathur A , Redington A E
Published: July 2002

In 1993, the British Thoracic Society (BTS) issued guidelines for the management of spontaneous pneumothorax. The aim of this study was to determine the level of adherence to and awareness of these guidelines at a London teaching hospital. A retrospective case note audit of 59 episodes of acute spontaneous pneumothorax was performed. In patients undergoing intervention, the initial procedure was simple aspiration in 32 (73%) and chest tube insertion in 12 (27%) cases, contrasting with the BTS recommendation that aspiration should be attempted first in all such patients. Simple aspiration was successful on 34% of occasions. Successful aspiration was associated with a significantly shorter hospital stay (median 3, range 1–11 days) than either failed aspiration (7, 3–66 days; p=0.003) or chest tube insertion without aspiration (9, 3–16 days; p=0.005). Other areas where practice differed from the BTS guidelines were clamping of chest tubes and use of a pursestring suture for wound closure. A follow up questionnaire survey suggested a lack of familiarity with the guidelines. These findings indicate that current management of spontaneous pneumothorax deviates from the BTS guidelines in a number of potentially important respects. Attention should be directed to improving awareness of and access to clinical guidelines.
Impact of smoking status on workplace absenteeism and productivity
Authors: Halpern Michael T , Shikiar Richard , Rentz Anne M , Khan Zeba M
Published: July 2002

OBJECTIVES

To: evaluate the impact of smoking status on objective productivity and absenteeism measures; evaluate the impact of smoking status on subjective measures of productivity; and assess the correlation between subjective and objective productivity measures.

DESIGN

Prospective cohort study in a workplace environment.

SUBJECTS

Approximately 300 employees (100 each of former, current, and never smokers) at a reservation office of a large US airline.

MAIN OUTCOME MEASURES

Objective productivity and absenteeism data were supplied by the employer. Subjective assessments of productivity were collected using a self report instrument, the Health and Work Questionnaire (HWQ).

RESULTS

Current smokers had significantly greater absenteeism than did never smokers, with former smokers having intermediate values; among former smokers, absenteeism showed a significant decline with years following cessation. Former smokers showed an increase in seven of 10 objective productivity measures as compared to current smokers, with a mean increase of 4.5%. While objective productivity measures for former smokers decreased compared to measures for current smokers during the first year following cessation, values for former smokers were greater than those for current smokers by 1–4 years following cessation. Subjective assessments of “productivity evaluation by others” and “personal life satisfaction” showed significant trends with highest values for never smokers, lowest for current smokers, and intermediate for former smokers.

CONCLUSIONS

Workplace productivity is increased and absenteeism is decreased among former smokers as compared to current smokers. Productivity among former smokers increases over time toward values seen among never smokers. Subjective measures of productivity provide indications of novel ways of productivity assessment that are sensitive to smoking status.
WHO Europe evidence based recommendations on the treatment of tobacco dependence
Authors: Raw M , Anderson P , Batra A , Dubois G , Harrington P , Hirsch A , Le Houezec J , McNeill A , Milner D , Poetschke Langer M , Zatonski W
Published: July 2002

The following recommendations on the treatment of tobacco dependence have been written as an initiative of the World Health Organization European Partnership Project to Reduce Tobacco Dependence.
Arbuscular mycorrhiza on root-organ cultures
Authors: Fortin J André , Bécard Guillaume , Declerck Stéphane , Dalpé Yolande , St-Arnaud Marc , Coughlan Andrew P , Piché Yves
Published: July 2002

The study of arbuscular mycorrhizal (AM) fungi and the AM symbiosis formed with host plant roots is complicated by the biotrophic and hypogeous nature of the mycobionts involved. To overcome this, several attempts have been made during the last three decades to obtain this symbiosis in vitro. The use of root-organ cultures has proved particularly successful. In this review, we describe the method by which root-organ cultures (transformed and nontransformed) have been obtained, together with the choice of host species, inoculation techniques, and culture media. We also outline the potential use of continuous cultures and cryopreservation of in vitro produced spores for long-term germ plasm storage. Furthermore, this review highlights the considerable impact that in vitro root-organ cultures have had on studies of AM fungal morphology, taxonomy, and phylogeny and how they have improved our understanding of the processes leading to root colonization and development of the extraradical mycelium. This is supported by a summary of some of the most important findings, regarding this symbiosis, that have been made at the physiological, biochemical, and molecular levels. We also summarize results from studies between AM fungi and certain pathogenic and nonpathogenic soil microorganisms. We describe some of the limitations of this in vitro system and propose diverse avenues of AM research that can now be undertaken, including the potential use of a similar system for ectomycorrhizal research.Key words: arbuscular mycorrhiza, root-organ cultures, Glomales, in vitro, root symbioses, source of inoculum, cryopreservation, intraradical and extraradical mycelium, mycorrhizosphere.
Analysis of the wavelength content of the longitudinal profiles for C-LTPP test sections
Authors: Doré Guy , Flamand Martin , Pascale Pierre
Published: July 2002

A new approach for pavement longitudinal profile analysis is described in this paper. In this approach, based on a simple moving average filtering technique, the results are expressed in terms of the proportion of the calculated international roughness index associated with different wavelengths of pavement surface deformations. The new approach has been successfully used in the assessment of the performance of Canadian Long-Term Pavement Performance (C-LTPP) test sites. The proposed analysis approach can help in identifying the source of problems causing pavement roughness. It can thus help in identifying the proper pavement rehabilitation technique. The new analysis approach has also helped in assessing the performance of the different rehabilitation techniques used in C-LTPP. It was found that 80130 mm thick overlays give the best results in reducing roughness associated with short wavelength deformations. The benefit of these overlays is, however, limited to several years. Moreover, overlays do not have any significant impact on long wavelength deformations. It has also been found that long wavelength distortions tend to dominate the longitudinal profiles of thin pavement structures or pavements built on soft fine grained soils. Short wavelength distortions are dominant in longitudinal profiles of cracked thick pavement structures or that are built on strong soils.Key words: pavement, performance, longitudinal profile, wavelength, IRI, roughness, deformations.
Detection of exon polymorphisms in the human lactoferrin gene
Authors: Liu Li-Herng Eric , Gladwell Wesley , Teng Christina T
Published: July 2002

We previously demonstrated that lactoferrin gene polymorphisms occur in cancer cells of patients with leukemia and breast cancer. In this study, we established a non-radioactive polymerase chain reactionsingle strand conformation polymorphism (PCRSSCP) analysis, one of the most sensitive and simplest methods to detect polymorphisms and mutations of the human lactoferrin gene. We optimized the PCR conditions for nine different DNA templates and 16 pairs of exon primers for SSCP analysis. The DNA templates used in the analyses were prepared from a cosmid clone (CT61) that contains the human lactoferrin gene, human placental tissue, leukocytes from 10 normal volunteers, leukemic cells of two patients, and previously established three breast and two leukemic cell lines. With the appropriate exon-primer sets, PCR products from exon 1 to exon 16 of the lactoferrin gene were generated from the DNA templates and analyzed by SSCP. Compared with the homogenous cloned DNA, lactoferrin gene polymorphisms were detected within exons 2, 5, 7, 9, 13, 14, and 15 of the normal placental and leukocyte DNA. In addition, abnormal migration patterns of the lactoferrin gene in cancer cells were detected in exons 4, 5, 13, 14, and 15. The PCRSSCP band migration patterns can be attributed either to gene polymorphism in normal cells or to DNA mutations in cancer cells and the employed method cannot distinguish between them. Nonetheless, the present analysis suggests that genetic polymorphisms of the lactoferrin gene exist in selected exons and additional mutations of the lactoferrin gene do occur in the cancer cells.Key words: lactoferrin, polymorphisms, human lactoferrin, single-strand conformation polymorphism (SSCP).
Medium-sized cyclophanes, part 59:1 Nitration of [3.3]- and [3.3.3]metacyclophanes  Through-space electronic interactions between two or three benzene rings
Authors: Yamato Takehiko , Tsuchihashi Koji , Nakamura Noriko , Hirahara Mai , Tsuzuki Hirohisa
Published: July 2002

The two tert-butyl groups of anti-6,15-di-tert-butyl-9,18-dimethoxy[3.3]metacyclophane (anti-4) are both ipso-nitrated even under mild reaction conditions such as copper(II) nitrate in an acetic anhydride solution because of the decreased deactivation of the second aromatic ring by the introduced nitro group. On the other hand, anti-5,13-di-tert-butyl-8,16-dimethoxy[2.2]metacyclophane (anti-1) undergoes replacement of only one tert-butyl group under the same reaction conditions. The higher yields of the twofold ipso-nitration product anti-7 were obtained in nitration of anti-4 with fuming nitric acid or mixed acid (HNO3H2SO4). Thus, the number of ipso-nitrations at the tert-butyl groups of anti-4 was strongly affected by the reactivity of the nitration reagent. Nitration of the corresponding syn-conformer syn-4 with copper(II) nitrate in an acetic anhydride solution, however, led only to the recovery of the starting compound. The presently developed procedure was further applied to the direct removal of the tert-butyl group by electrophilic substitution of the larger-sized ring macrocyclic metacyclophanes, cone- and partial-cone-tri-tert-butyl[3.3.3]metacyclophanes 11.Key words: [3n]metacyclophanes, conformation, ipso-nitration, through-space electronic interaction, crystal structure.
Assigning structures to diastereomeric aliphatic α,α'-dibromo ketones
Authors: Parvez Masood , Kabir SM Humayan , Sorensen Ted S , Sun Fang , Watson Brian
Published: July 2002

X-ray crystal structures are reported for two symmetrical aliphatic α,α'-dibromo ketones: a meso diastereomer of 3,5-dibromo2,2,6,6-tetramethylheptan-4-one, and a rac isomer of 4,6-dibromo2,2,3,3,7,7,8,8-octamethylnonan-5-one. Using these secure assignments and a previously confirmed structure for the diastereomers of 2,4-dibromopentan-3-one, we show in this study that gas-liquid chromatography (GLC) retention times (meso > rac) can be used to confidently assign the diastereomers for a range of symmetrical and unsymmetrical aliphatic α,α'-dibromo ketones. 1H NMR chemical shifts for the >CHBr hydrogen(s) can also be corroboratively used for assignment purposes (δracH > δmesoH).Key words: α,α'-dibromo ketones, X-ray crystal structures, GLC retention times, isomer assignment
Medium-size cyclophanes. Part 601: Synthesis and conformational studies of 9-substituted [3.3]metacyclophane-2,11-diones and conversion to the corresponding [3.3]metacyclophanes
Authors: Yamato Takehiko , Tsuchihashi Koji , Nakamura Noriko , Hirahara Mai , Tanaka Kan
Published: July 2002

Various syn- and anti-9-substituted [3.3]metacyclophane-2,11-diones are obtained by the coupling reaction of the corresponding 2,6-bis(bromomethyl)benzenes (3) with 2,6-bis[2-cyano-2-(toluenesulfony)ethyl]-4-tert-butyl-1-substituted benzenes (4) in dimethylformamide (DMF) with an excess of sodium hydride. Depending on the substituents at positions 1 and 4 on 3, different yields (inversion of selectivity) of anti-5 and syn-5 were achieved.Key words: metacyclophanes, cyclization, conformation, CH-π interaction, through-space interaction, charge-transfer-type interaction.
Statistical quality control analysis of forest fire activity in Canada
Authors: Podur Justin , Martell David L , Knight Keith
Published: July 2002

Statistical quality-control methods were used to detect significant changes in the mean and variance of the annual fire occurrence and area burned in Canada (19182000), Ontario (19172000), and northwestern Ontario (19172000). The quality-control chart method employed uses the first half of the record of a process as a baseline to test for significant changes in the mean or variance of the process in the second half of the record. Significant increases were detected in annual area burned and in fire occurrence in Canada, Ontario, and northwestern Ontario.
Dynamics of eastern larch stands and its relationships with larch sawfly outbreaks in the northern Clay Belt of Quebec
Authors: Girardin Martin-Philippe , Tardif Jacques , Bergeron Yves
Published: July 2002

Climate change, fires, and insects outbreaks can affect eastern larch (Larix laricina (Du Roi) K. Koch) stand dynamics. To determine which of these factors had the greatest influence on stand dynamics, we sampled four wetlands dominated by larch on the margin of Lake Duparquet in the northern Clay Belt of Quebec. The ages of seedlings, saplings, and trees were determined in twelve 400-m2 plots. Increment cores were taken at breast height to determine past disturbance episodes related, among others, to larch sawfly (Pristiphora erichsonii (Hartig)) activity. Stem analysis was conducted using larch and black spruce (Picea mariana (Mill.) BSP) for identification of post-disturbance releases in height growth. Analyses at the stand and cluster levels showed that larch age structures were characterized by many unsynchronized establishment periods. In addition, a seedlings bank not much older than 10 years characterized many plots. Two larch sawfly outbreak episodes (18951912 and 19551962) identified by tree-ring and stem analysis were associated with larch establishment. A smaller outbreak in the late 1970s could also have contributed to the initiation of establishment in one stand. Our results suggest that the length (severity) of an outbreak may be a critical factor in explaining the different patterns of establishment observed in these stands. During a severe outbreak, larch establishment may occur mainly from surviving stems (increased seed production), whereas during a mild outbreak, larch establishment may occur from increased survival of pre-established seedlings and saplings. Further studies on the distribution of gaps within larch stands may provide better information on the pattern of mortality (gap dynamics) during an outbreak and may help to better understand larch establishment in these stands.
Calling-song function in male haglids (Orthoptera: Haglidae,Cyphoderris)
Authors: Morris Glenn K , DeLuca Paul A , Norton Matthew , Mason Andrew C
Published: July 2002

We studied the response of males to the singing of nearby male conspecifics in two species of the orthopteran genus Cyphoderris, primitive relatives of crickets and katydids. Lone male Cyphoderris buckelli stridulating in a large cage made a phonotactic approach to a nearby speaker broadcasting conspecific calling song. But in field experiments no phonotaxis to song broadcasts occurred; rather, a significant number of male C. buckelli increased their chirp duty cycle and pulse rate. There was no change in their carrier frequency. Calling male Cyphoderris monstrosa were exposed in the field to (i) playback of a synthetic calling song at a typical conspecific pulse rate, (ii) relayed broadcast of their own call, and (iii) low-frequency audio noise. Call duty cycle decreased significantly in response to the noise, while the pooled song models fell just short of significance. Singing C. buckelli were marked individually and their perches flagged over successive nights. We observed low site fidelity and extensive male displacement. Such behaviour is inconsistent with defense of topographically fixed singing territories and concurs with the absence of fighting in this species. Chirp duty cycle was increased significantly in C. buckelli in response to the singing of nearby conspecifics, but unlike in C. monstrosa, this change in duty cycle plays no role in overt aggression, though it may maintain a male's relative attractiveness to females.
VERIFYING PROBABILISTIC PROGRAMS USING A HOARE LIKE LOGIC
Authors: DEN HARTOG J. I. , DE VINK E. P.
Published: July 2002

Probability, be it inherent or explicitly introduced, has become an important issue in the verification of programs. In this paper we study a formalism which allows reasoning about programs which can act probabilistically. To describe probabilistic programs, a basic programming language with an operator for probabilistic choice is introduced and a denotational semantics is given for this language. To specify propertics of probabilistic programs, standard first order logic predicates are insufficient, so a notion of probabilistic predicates is introduced. A Hoare-style proof system to check properties of probabilistic programs is given. The proof system for a sublanguage is shown to be sound and complete; the properties that can be derived are exactly the valid properties. Finally some typical examples illustrate the use of the probabilistic predicates and the proof system.
DIRICHLET FORMS IN TERMS OF WHITE NOISE ANALYSIS I: CONSTRUCTION AND QFT EXAMPLES
Authors: ALBEVERIO S. , HIDA T. , POTTHOFF J. , RÖCKNER M. , STREIT L.
Published: July 2002

Random fields are given in terms of measures which (in general) are singular with respect to that of white noise. However, many such measures can be expressed in terms of white noise through a positive generalized functional acting as a generalized Radon-Nikodym derivative. We give criteria for this to be the case and show that these criteria are fulfilled by Schwinger and Wightman functionals of various nontrivial quantum field theory models. Furthermore a number of closability criteria are given and discussed for the Dirichlet forms associated with positive generalized functionals of white noise. In a second paper we apply these results to the construction of Markov and of quantum fields.
ON SPECTRAL THEORY OF SELFADJOINT FELLER GENERATORS
Authors: DEMUTH M. , VAN CASTEREN J.A.
Published: July 2002

Upon introducing the theory of (symmetric) Feller semigroups, regularly and singularly perturbations of generators of Feller semigroups are studied. For the regular perturbations potentials belonging to the Kato-Feller class are admitted. The singular perturbations arise from potential barriers with increasing height. The Feynman-Kac representation is derived for the singular case. Selfadjointness conditions are given for these perturbed generators of Feller semigroups. Up to some extent we give explicit forms. The second main part consists of spectral theoretical considerations for these perturbed Feller generators. We give some examples which indicate the usefulness of the Feynman-Kac formula in spectral theory. We are interested in compactness properties of semigroup differences, which consist of trace class or Hilbert-Schmidt operators.
A PROBABILISTIC FORMULATION OF BOSONIC AND FERMIONIC INTEGRATION
Authors: KUPSCH J.
Published: July 2002

A unified picture of bosonic and fermionic integration is presented. The Wiener isomorphism between the bosonic Fock space and the space of functions which are square integrable with respect to the canonical Gaussian promeasure of the basic Hilbert space is extended to the fermionic Fock space. Bosonic and fermionic functionals can be identified with Gaussian integrals on the same probability space.
EXPONENTIAL APPROACH TO THE ADIABATIC LIMIT AND THE LANDAU-ZENER FORMULA
Authors: JAKŠIĆ V , SEGERT J.
Published: July 2002

We study the adiabatic limit for Hamiltonians with certain complex-analytic dependence on the time variable We show that the transition probability from a spectral band that is separated by gaps is exponentially small in the adiabatic parameter We find sufficient conditions for the Landau-Zener formula, and its generalization to nondiscrete spectrum, to bound the transition probability
BRST AND l(1, 1)
Authors: HORUZHY S. S. , VORONIN A. V.
Published: July 2002

A very close connection between the BRST symmetry and the Lie superalgebra l(1, 1) is pointed out and studied. Structure of l(1, 1), its involutions and automorphisms are described. Absence of infinite-dimensional irreducible representations (IR) of l(1, 1) is proved. The rigorous construction and decomposition into IR is performed for the class of l(1, 1) representations corresponding to physical BRST theories and consisting of infinite-dimensional doubly involutive representations in J-spaces. As a first output of the l(1, 1) formalism, a new formula for the BRST charge is derived.