Spectrally Similar Incommensurable 3-Manifolds

Reid has asked whether hyperbolic manifolds with the same geodesic length spectrum must be commensurable. Building toward a negative answer to this question, we construct examples of hyperbolic 3–manifolds that share an arbitrarily large portion of the length spectrum but are not commensurable. More precisely, for every n ≫ 0, we construct a pair of incommensurable hyperbolic 3–manifolds Nn and Nµn whose volume is approximately n and whose length spectra agree up to length n. Both Nn and Nµn are built by gluing two standard submanifolds along a complicated pseudo-Anosov map, ensuring that these manifolds have a very thick collar about an essential surface. The two gluing maps differ by a hyper-elliptic involution along this surface. Our proof also involves a new commensurability criterion based on pairs of pants

Kiezen tussen twee kwaden

Achtergrond: Uitgeprocedeerde asielmigranten – daaronder zijn zowel asielzoekers van wie de asielaanvraag is afgewezen als voormalige asielvergunninghouders met een tijdelijke verblijfsvergunning die is geëindigd – moeten Nederland in beginsel binnen 28 dagen te verlaten. Wie niet zelfstandig vertrekt, riskeert uitzetting. Uit eerder onderzoek komt naar voren dat zelfstandige terugkeer vaak problematisch is; in de praktijk blijft een aanzienlijke minderheid van de uitgeprocedeerde asielmigranten in Nederland als illegale migrant

Relationship between environmental exposure to pesticides and anthropometric outcomes of boys in the rural Western Cape, South Africa

BACKGROUND: Rural residents in the Western Cape (WC), South Africa (SA) are highly exposed to agricultural pesticides that could impact their reproductive development. However, epidemiological evidence of the effect of pesticides on pubertal growth is contradictory. OBJECTIVE: To investigate the effect of pesticide exposure measured using indices of environmental exposure to pesticides on the pubertal growth of boys in rural WC, SA. METHODS: A cross-sectional study of 269 boys (177 of whom gave a history of residing on farms) was conducted. A questionnaire was administered, height and weight were measured and body mass index was calculated. A proximity index (PI) and spraying index (SI) was developed, measuring the lifetime average home distance from pesticide spraying and average frequency of spraying pesticides on a farm, respectively. RESULTS: Median age of boys was 12.4 years (interquartile range 9.5 - 13.3). More than 60% boys had height and weight <50th percentile for age. After adjusting for confounders, PI was significantly associated with shorter stature and lower weight (-1.7 cm/10-fold decrease, p=0.02 and -1.24 kg/10-fold decrease, p=0.04; respectively) and SI was non-significantly associated (-1.4 cm/10-fold increase, p=0.05 and -1.1 cm/10-fold increase, p=0.06; respectively). Associations were stronger for boys aged <11 years and were weaker when excluding non- farm boys. There were no other associations between outcome and exposure. CONCLUSIONS: The use of quantitative exposure indices showed that lower heights and weights might be associated with pesticide exposure in farm boys v. non-farm boys, but not among farm boys. Lower anthropometric measurements among farm boys v. non-farm boys appear stronger at a younger age. The indices of environmental exposure to pesticides require further development

An international prospective general population-based study of respiratory work disability

Background: Previous cross-sectional studies have shown that job change due to breathing problems at the workplace (respiratory work disability) is common among adults of working age. That research indicated that occupational exposure to gases, dust and fumes was associated with job change due to breathing problems, although causal inferences have been tempered by the cross-sectional nature of previously available data. There is a need for general population-based prospective studies to assess the incidence of respiratory work disability and to delineate better the roles of potential predictors of respiratory work disability.Methods: A prospective general population cohort study was performed in 25 centres in 11 European countries and one centre in the USA. A longitudinal analysis was undertaken of the European Community Respiratory Health Survey including all participants employed at any point since the baseline survey, 6659 subjects randomly sampled and 779 subjects comprising all subjects reporting physician-diagnosed asthma. The main outcome measure was new-onset respiratory work disability, defined as a reported job change during follow-up attributed to breathing problems. Exposure to dusts (biological or mineral), gases or fumes during follow-up was recorded using a job-exposure matrix. Cox proportional hazard regression modelling was used to analyse such exposure as a predictor of time until job change due to breathing problems.Results: The incidence rate of respiratory work disability was 1.2/1000 person-years of observation in the random sample (95% CI 1.0 to 1.5) and 5.7/1000 person-years in the asthma cohort (95% CI 4.1 to 7.8). In the random population sample, as well as in the asthma cohort, high occupational exposure to biological dust, mineral dust or gases or fumes predicted increased risk of respiratory work disability. In the random sample, sex was not associated with increased risk of work disability while, in the asthma cohort, female sex was associated with an increased disability risk (hazard ratio 2.8, 95% CI 1.3 to 5.9).Conclusions: Respiratory work disability is common overall. It is associated with workplace exposures that could be controlled through preventive measures

Gender-Specific Associations of Marine n-3 Fatty Acids and Fish Consumption with 10-Year Incidence of Stroke

Background: There is some evidence that the association of fish and marine fatty acids with stroke risk differs between men and women. We investigated the gender-specific associations of habitual intake of the marine fatty acids eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) and fish on incident stroke in a population-based study in the Netherlands. Methods: We prospectively followed 20,069 men and women, aged 20–65 years, without cardiovascular diseases at baseline. Habitual diet was assessed with a validated 178-item food frequency questionnaire. Incidence of stroke was assessed through linkage with mortality and morbidity registers. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HR) and 95 % confidence intervals (95%CI). Results: During 8–13 years of follow-up, 221 strokes occurred. In women, an inverse dose-response relation (P-trend = 0.02) was observed between EPA-DHA intake and incident stroke, with an HR of 0.49 (95 % CI: 0.27–0.91) in the top quartile of EPA-DHA (median 225 mg/d) as compared to the bottom quartile (median 36 mg/d). In men, the HR (95%CI) for the top quartile of EPA-DHA intake was 0.87 (0.51–1.48) (P-trend = 0.36). Similar results were observed for fish consumption and stroke incidence. Conclusion: A higher EPA-DHA and fish intake is related to a lower stroke risk in women, while for men an inverse association could not be demonstrated

Morphology and function of preserved microvascular arterial grafts: an experimental study in rats

The aim of this study is to examine the morphology and function and small-caliber, arterial grafts after preservation in the University of Wisconsin solution (UW). Rat carotid arteries were stored in UW (n = 10) or in phosphate-buffered saline (PBS) (n = 10) for 1, 3, 7, and 14 days and were examined with light microscopy (LM) and scanning electron microscopy (SEM). Rat aortic preparations were stored in UW or PBS for 1 hour, 24 hours, 72 hours, 7 days, and 14 days and assessed for functional responses (stimulated contraction and endothelium-dependent relaxation). Segments (5 mm) of rat carotid arteries were stored in UW or PBS for 3 days, 7 days, and 14 days and orthotopically implanted as autografts and allografts. No immunosuppressive or anticoagulant agents were used. After 28 days of implantation, the grafts were assessed for patency and excised for LM and SEM. In UW, the endothelial layer remained intact up to 9 days of storage. In PBS, the endothelial layer showed deterioration after 1 day and was completely lost after 3 days. Functional responses were demonstrated to exist for as long as 7 days storage in UW. In PBS, no responses could be evoked after 24 hours storage. Autografts preserved in UW for 3 days (n = 6), 7 days (n = 6), and 14 days (n = 6) showed patency rates of 83.3%, 66.6%, and 66.6%, respectively, whereas patency rates of allografts were 66.6%, 33.3%, and 33.3%, respectively. Autografts stored in PBS for 3 days (n = 6), 7 days (n = 6), and 14 days (n = 6) showed patency rates of 33.3%, 33.3%, and 50%, respectively, whereas patency rates of allografts were 16.7%, 0%, and 33.3%, respectively. The UW preserved autografts showed normal morphology. All other groups showed vessel wall degeneration which in the allograft groups, were accompanied by lymphocellular infiltration. In conclusion, the endothelial layer and vessel wall of arteries are adequately preserved in UW. Functional responses are retained up to 14 days storage in UW, but, are lost after 24 hours storage in PBS. Autograft implantation studies accordingly show good performance of arterial segments preserved in UW, whereas allografts are subject to degradation as a result of rejectio

Raw and Processed Fruit and Vegetable Consumption and 10-Year Coronary Heart Disease Incidence in a Population-Based Cohort Study in the Netherlands

Background: Prospective cohort studies have shown that high fruit and vegetable consumption is inversely associated with coronary heart disease (CHD). Whether food processing affects this association is unknown. Therefore, we quantified the association of fruit and vegetable consumption with 10-year CHD incidence in a population-based study in the Netherlands and the effect of processing on these associations. Methods: Prospective population-based cohort study, including 20,069 men and women aged 20 to 65 years, enrolled between 1993 and 1997 and free of cardiovascular disease at baseline. Diet was assessed using a validated 178-item food frequency questionnaire. Hazard ratios (HR) were calculated for CHD incidence using multivariable Cox proportional hazards models. Results: During a mean follow-up time of 10.5y, 245 incident cases of CHD were documented, which comprised 211 nonfatal acute myocardial infarctions and 34 fatal CHD events. The risk of CHD incidence was 34 % lower for participants with a high intake of total fruit and vegetables (.475 g/d; HR: 0.66; 95 % CI: 0.45–0.99) compared to participants with a low total fruit and vegetable consumption (#241 g/d). Intake of raw fruit and vegetables (.262 g/d vs #92 g/d; HR: 0.70; 95 % CI: 0.47–1.04) as well as processed fruit and vegetables (.234 g/d vs #113 g/d; HR: 0.79; 95 % CI: 0.54–1.16) were inversely related with CHD incidence

Papillomavirus Infection of the Anogenital Region: Correlation Between Histology, Clinical Picture, and Virus Type. Proposal of a New Nomenclature

The clinical and histologic picture of 84 anogenital condylomatous and condyloma-like lesions of both sexes were analyzed in an effort to establish a correlation to the different papillomavirus (PV) types. The presence of human papillomavirus (HPV)-specific DNA sequences was confirmed through molecular hybridization and the presence of PV structure antigens was verified in thin sections by means of a group-specific anti-PV-antiserum using the peroxidase-antiperoxidase (PAP) technique. Three distinct clinical forms harboring distinct HPV types were distinguished: (1) Condylomata acuminata in which HPV-6 DNA was present in 37 of 59 samples and HPV-11 DNA in only 13 of 59 samples. HPV-16 DNA was not detected at all and 9 condylomatous lesions remained unclassified. (2) Flat condyloma-like lesions, where HPV-6 and HPV- 11 were associated with lesions of low epidermal atypia in 8 and in 2 of 18 cases, respectively, and where HPV-16 was associated exclusively with 6 of 18 such lesions with severe atypia, called bowenoid papulosis. (3) Pigmented papules where HPV16 was detected twice in lesions of bowenoid papulosis and HPV-11 in 2 of the benign pigmented lesions. The fourth clinical manifestation of genital papillomavirus infections—the so-called condylomata plana—was not available for virologic analysis. Histologically 5 different koilocytotic features were determined which could not be correlated either with one of the clinical pictures or with a specific PV type. HPV-16, however, was found frequently in non-koilocytotic lesions exhibiting the features of severe epithelial atypia known in bowenoid papulosis. The existence of PV structure antigens in these lesions could not be verified using the indirect immunoperoxidase—PAPtechnique—in contrast to the koilocytotic lesions where clear evidence of the presence of HPV was proved in 36 of 56 (64.3%) of the cases