651 research outputs found

    Biometric imaging: three dimensional imaging of the human hand using coded structured lighting

    Get PDF
    In this report the results of applying a three dimensional range imaging system, based on coded structured light, are presented. This includes a description of a new improved spatial coding scheme. This new scheme increases the number of reference points available and provides a basis for more accurate calculation of their location. A detailed description of the image processing methods used to extract structural information and to identify structural objects from the camera image are given. In addition the method used to calculate the locations of reference points with \u27subpixel\u27 accuracy is described. Finally, the results of experiments with synthesised and projected structured light images are presented

    Production Technology and Competitiveness In the Hungarian Manufacturing Industry

    Get PDF
    Following the big transformations of the 1990s, enterprise structure and technological level seem to have become stabilised in Hungary. Under these circumstances it is especially interesting to identify the elements responsible for competitiveness in general, and the role technology plays in development in particular, according to managers experienced in production and marketing. This empirical study – based on in-depth interviews and field research – summarises characteristics of the technological level in the sectors examined, role of technology and labour in production, effects of foreign direct investment, relations between competition and firm-level factors determining competitiveness, and concludes by summing up those most frequently mentioned proposals that should be incorporated into economic policy according to managers. Main findings indicate that more qualified, more intensive and cheaper labour can be substituted for high technology. The competitiveness of an enterprise is not determined by technology alone, but rather by a combination of technology, the parameters of available labour and the costs of investment increasing productivity. The insufficiency of inter-company relations, together with a shortage of available assets necessary for investment constitute the major threat undermining the competitiveness of enterprises in present-day Hungary

    The serum copper/zinc ratio in childhood and educational attainment: a population-based study

    Get PDF
    BACKGROUND: Micronutrients are potentially important determinants of adult outcomes such as educational attainment. Copper and zinc have known effects on several medical conditions and cognitive development. Elevated copper and depressed zinc is a common trace metal imbalance. METHODS: We estimate the correlation between the copper/zinc ratio (Cu/Zn) in childhood (year 1980) and educational attainment in adulthood (year 2010). We use the Young Finns Study (YFS) combined with the Finnish Linked Employer-Employee Data (FLEED). The regression models account for confounders such as other biomarkers and parental observables. RESULTS: We report a sizeable, negative correlation between Cu/Zn and educational attainment as measured by education in years, grades as well as the likelihood of completing university education. For example, a one standard deviation increase in Cu/Zn decreases the probability of university education by ∌4%. CONCLUSIONS: The findings are consistent with a Cu/Zn effect influencing cognitive functioning early in life. Future research should explore more deeply the precise mechanisms by which Cu/Zn affects educational attainment

    Stringency of the 2-His–1-Asp Active-Site Motif in Prolyl 4-Hydroxylase

    Get PDF
    The non-heme iron(II) dioxygenase family of enzymes contain a common 2-His–1-carboxylate iron-binding motif. These enzymes catalyze a wide variety of oxidative reactions, such as the hydroxylation of aliphatic C–H bonds. Prolyl 4-hydroxylase (P4H) is an α-ketoglutarate-dependent iron(II) dioxygenase that catalyzes the post-translational hydroxylation of proline residues in protocollagen strands, stabilizing the ensuing triple helix. Human P4H residues His412, Asp414, and His483 have been identified as an iron-coordinating 2-His–1-carboxylate motif. Enzymes that catalyze oxidative halogenation do so by a mechanism similar to that of P4H. These halogenases retain the active-site histidine residues, but the carboxylate ligand is replaced with a halide ion. We replaced Asp414 of P4H with alanine (to mimic the active site of a halogenase) and with glycine. These substitutions do not, however, convert P4H into a halogenase. Moreover, the hydroxylase activity of D414A P4H cannot be rescued with small molecules. In addition, rearranging the two His and one Asp residues in the active site eliminates hydroxylase activity. Our results demonstrate a high stringency for the iron-binding residues in the P4H active site. We conclude that P4H, which catalyzes an especially demanding chemical transformation, is recalcitrant to change

    The alpha v beta 1 integrin functions as a fibronectin receptor but does not support fibronectin matrix assembly and cell migration on fibronectin

    Get PDF
    The fibronectin receptor, alpha 5 beta 1, has been shown to be required for fibronectin matrix assembly and plays an important role in cell migration on fibronectin. However, it is not clear whether other fibronectin binding integrins can take the place of alpha 5 beta 1 during matrix assembly and cell migration. To test this, we expressed the human alpha v subunit in the CHO cell line CHO-B2 that lacks the alpha 5 subunit. We found that the human alpha v combined with CHO cell beta 1 to form the integrin alpha v beta 1. Cells that expressed alpha v beta 1 attached to and spread well on fibronectin-coated dishes, but did so less well on vitronectin-coated dishes. This, along with other data, indicated that alpha v beta 1 functions as a fibronectin receptor in CHO-B2 cells. The alpha v beta 1-expressing cells failed to produce a fibronectin matrix or to migrate on fibronectin, although the same cells transfected with alpha 5 do produce a matrix and migrate on fibronectin. The affinity of the alpha v beta 1-expressing cells for fibronectin was fourfold lower than that of the alpha 5 beta 1- expressing cells. In addition, alpha v beta 1 was distributed diffusely throughout the cell surface, whereas alpha 5 beta 1 was localized to focal adhesions when cells were seeded onto fibronectin-coated surfaces. Thus, of the two fibronectin receptors, alpha v beta 1 and alpha 5 beta 1, only alpha 5 beta 1 supports fibronectin matrix assembly and promotes cell migration on fibronectin in the CHO-B2 cells. Possible reasons for this difference in the activities of alpha v beta 1 and alpha 5 beta 1 include the lower affinity of alpha v beta 1 for fibronectin and the failure of this integrin to localize in adhesion plaques on a fibronectin substrate. These results show that two integrins with similar ligand specificities and cell attachment functions may be quite different in their ability to support fibronectin matrix assembly and cell motility on fibronectin

    Fitness and Adiposity as Predictors of Functional Limitation in Adults

    Get PDF
    Background: This study examined the associations of body mass index (BMI), waist circumference (WC), and cardiorespiratory fitness (CRF) with incident functional limitation (IFL) in adults. Methods: Patients (n = 2400), 30+ years [mean age, 45.2 (SD, 8.3); 12% women], completed a baseline health examination during 1979 to 1995. CRF was quantified by age- and sex-specific thirds for maximal treadmill exercise test duration. Adiposity was assessed by BMI and WC (grouped for analysis according to clinical guidelines). Incident IFL was identified from mail-back surveys during 1995, 1999, and 2004. Results: After adjusting for potential confounders and either BMI or WC, CRF was inversely related to IFL (P trend \u3c.001). The association between BMI and IFL was significant after adjusting for all confounders (P trend = .002), but not after additional adjustment for CRF (P trend = .23). After controlling for all confounders and CRF, high WC was associated with greater odds of IFL in those aged 30 to 49; normal WC was associated with greater odds of IFL in those aged 50+. Conclusions: CRF was a significant predictor of IFL in middle aged and older adults, independent of overall or abdominal adiposity. Clinicians should consider the importance of preserving functional capacity by recommending regular physical activity for normal-weight and overweight individuals

    Near-infrared rechargeable glass-based composites for green persistent luminescence

    Get PDF
    The fabrication of Yb3+, Tm3+ co-doped oxyfluorophosphate glass-based composites, with green persistent luminescence after being charged with near-infrared light, is demonstrated. The mechanism responsible for the green afterglow after near-infrared illumination is unveiled. The composite is prepared using a modified melting process to limit the evaporation of fluorine during melting. Intense (blue and ultraviolet) up-conversion emission is obtained by optimizing the Yb2O3 and Tm2O3 concentrations. A heat treatment promotes volume precipitation of Yb3+, Tm3+ co-doped CaF2 crystals. Although the intensity of the blue up-conversion emission from the Tm3+ 1G4 level is lower in the highly Yb3+-concentrated glass-ceramic due to reverse energy transfer from Tm3+ to Yb3+, the heat treatment leads to an increase of the intensity of the emissions around 346 nm, 361 nm nm and 450 nm coming from the Tm3+ 1I6 and 1D2 levels. By combining the Yb3+ and Tm3+ ions with SrAl2O4:Eu2+,Dy3+crystals, green afterglow can be obtained after charging with near-infrared light.</p

    Evaluation of a standard provision versus an autonomy promotive exercise referral programme: rationale and study design

    Get PDF
    Background The National Institute of Clinical Excellence in the UK has recommended that the effectiveness of ongoing exercise referral schemes to promote physical activity should be examined in research trials. Recent empirical evidence in health care and physical activity promotion contexts provides a foundation for testing the utility of a Self Determination Theory (SDT) -based exercise referral consultation. Methods/Design Design: An exploratory cluster randomised controlled trial comparing standard provision exercise on prescription with a Self Determination Theory-based (SDT) exercise on prescription intervention. Participants: 347 people referred to the Birmingham Exercise on Prescription scheme between November 2007 and July 2008. The 13 exercise on prescription sites in Birmingham were randomised to current practice (n=7) or to the SDT-based intervention (n=6). Outcomes measured at 3 and 6-months: Minutes of moderate or vigorous physical activity per week assessed using the 7-day Physical Activity Recall; physical health: blood pressure and weight; health status measured using the Dartmouth CO-OP charts; anxiety and depression measured by the Hospital Anxiety and Depression Scale and vitality measured by the subjective vitality score; motivation and processes of change: perceptions of autonomy support from the advisor, satisfaction of the needs for competence, autonomy, and relatedness via physical activity, and motivational regulations for exercise. Discussion This trial will determine whether an exercise referral programme based on Self Determination Theory increases physical activity and other health outcomes compared to a standard programme and will test the underlying SDT-based process model (perceived autonomy support, need satisfaction, motivation regulations, outcomes) via structural equation modelling. Trial registration The trial is registered as Current Controlled trials ISRCTN07682833

    24-h urinary sodium excretion and the risk of adverse outcomes

    Get PDF
    AimsThe objective was to evaluate whether sodium intake, assessed with the gold standard 24-h urinary collections, was related to long-term incidence of death, cardiovascular disease (CVD) and diabetes mellitus (DM). MethodsA cohort of 4630 individuals aged 25-64 years collected 24-h urine samples in 1979-2002 and were followed up to 14 years for the incidence of any CVD, coronary heart disease (CHD), stroke, heart failure (HF) and DM event, and death. Cox proportional hazards models were used to estimate the association between the baseline salt intake and incident events and adjusted for baseline age, body mass index, serum cholesterol, prevalent DM, and stratified by sex and cohort baseline year. ResultsDuring the follow-up, we observed 423 deaths, 424 CVD events (288 CHD events, 142 strokes, 139 HF events) and 161 DM events. Compared with the highest quartile of salt intake, persons in the lowest quartile had a lower incidence of CVD (hazard ratio [HR] 0.70; 95% confidence interval [CI], 0.51-0.95, p = .02), CHD (HR 0.63 [95% CI 0.42-0.94], p = .02) and DM (HR 0.52 [95% CI 0.31-0.87], p = .01). The results were non-significant for mortality, HF, and stroke.Conclusion High sodium intake is associated with an increased incidence of CVD and DM.</div
    • 

    corecore