| 1. |
- Abazov, V. M., et al.
(författare)
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Determination of the strong coupling constant from the inclusive jet cross section in pp collisions at s=1.96 TeV
- 2009
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Ingår i: PHYS REV D. - 1550-7998 .- 1550-2368. ; 80, s. 111107-
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Tidskriftsartikel (refereegranskat)abstract
- We determine the strong coupling constant alpha(s) and its energy dependence from the p(T) dependence of the inclusive jet cross section in pp collisions at s=1.96 TeV. The strong coupling constant is determined over the transverse momentum range 50 < p(T)< 145 GeV. Using perturbative QCD calculations to order O(alpha(3)(s)) combined with O(alpha(4)(s)) contributions from threshold corrections, we obtain alpha(s)(M-Z)=0.1161(-0.0048)(+0.0041). This is the most precise result obtained at a hadron-hadron collider.
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| 2. |
- Garcia-Salicetti, S., et al.
(författare)
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Biosecure reference systems for on-line signature verification : A study of complementarity
- 2007
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Ingår i: Annales des télécommunications. - : Springer. - 0003-4347 .- 1958-9395. ; 62:1-2, s. 36-61
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present an integrated research study in On-line Signature Verification undertaken by several teams that participate in the BioSecure Network of Excellence. This integrated work, started during the First BioSecure Residential Workshop, has as main objective the development of an On-line Signature Verification evaluation platform. As a first step, four On-line Signature Verification Systems based on different approaches are evaluated and compared following the same experimental protocol on MCYT signature database, which is the largest existing on-line western signature database publicly available with 16 500 signatures from 330 clients. A particular focus of work documented in this paper is multi-algorithmic fusion in order to study the complementarity of the approaches involved. To this end, a simple fusion method based on the Mean Rule is used after a normalization phase.
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| 3. |
- Garcia-Salicetti, S., et al.
(författare)
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Online Handwritten Signature Verification
- 2009
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Ingår i: Guide to Biometric Reference Systems and Performance Evaluation. - London : Springer London. - 9781848002913 ; , s. 125-165
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In this chapter, we first provide an overview of the existing main approaches, databases, evaluation campaigns and the remaining challenges in online handwritten signature verification. We then propose a new benchmarking framework for online signature verification by introducing the concepts of “Reference Systems”, “Reference Databases” and associated “Reference Protocols.” Finally, we present the results of several approaches within the proposed evaluation framework. Among them are also present the best approaches within the first international Signature Verification Competition held in 2004 (SVC’2004), Dynamic Time Warping and Hidden Markov Models. All these systems are evaluated first within the benchmarking framework and also with other relevant protocols. Experiments are also reported on two different databases (BIOMET and MCYT) showing the impact of time variability for online signature verification. The two reference systems presented in this chapter are also used and evaluated in the BMEC’2007 evaluation campaign, presented in Chap11. ©Springer 2009
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| 4. |
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Labayen, Idoia, et al.
(författare)
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Association of common variants of UCP2 gene with low-grade inflammation in Swedish children and adolescents : the European Youth Heart Study
- 2009
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Ingår i: Pediatric Research. - : Nature Publishing Group. - 0031-3998 .- 1530-0447. ; 66:3, s. 350-354
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Tidskriftsartikel (refereegranskat)abstract
- We examined the associations of two functional variants 866G>A and DEL/INS polymorphisms of UCP2 gene with low-grade inflammatory proteins (C-reactive protein, fibrinogen, complement C3 [C3], and complement C4 [C4]) in 131 children (52.7% boys, aged 9.5 +/- 0.4 y) and 118 adolescents (44.1% males, aged 15.5 +/- 0.4 y) selected from the European Youth Heart Study. Differences in inflammatory markers among the genotype variants of the two UCP2 gene polymorphisms were analyzed after adjusting for sex, age, pubertal stage, fitness, and fatness. The results showed that fibrinogen, C3, and C4 were higher in GG carriers than in subjects carrying the A allele of the 866G>A polymorphism of the UCP2 gene (UCP2 -866G>A) polymorphism (all p < 0.05). The DEL/DEL genotype of 45nt deletion/insertion variant polymorphism of the UCP2 gene (UCP2 DEL/INS) was associated with higher C3 (p < 0.05) than DEL/INS and INS/INS genotypes. This study provides evidence of a role of UCP2 -866G>A in modifying low-grade inflammatory state in apparently healthy children and adolescents. Given the implication of complement factors on atherosclerosis process, these results contribute to explain the reduced cardiovascular risk associated with the A allele of the UCP2 -866G>A polymorphism.
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| 9. |
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| 10. |
- Macias Garcia, B., et al.
(författare)
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Centrifugation on a single layer of colloid selects improved quality spermatozoa from frozen-thawed stallion semen
- 2009
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Ingår i: Animal Reproduction Science. - : Elsevier Masson. - 0378-4320 .- 1873-2232. ; 114:1-3, s. 193-202
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Tidskriftsartikel (refereegranskat)abstract
- The present study attempted to select the subpopulation of stallion spermatozoa that best survived a conventional freezing and thawing procedure, using centrifugation of post-thawed semen samples through a single layer of a glycidoxypropyltrimethoxysilane-coated silica colloid with a species-specific formulation (Androcoll-E (TM)). Sperm motility, sperm chromatin structure, membrane integrity and mitorchondrial membrane potential were studied in filtered and non-filtered spermatozoa. Single-layer centrifugation (SLC) using Androcoll-E (TM) significantly improved all the sperm parameters studied, implying SLC may be a simple approach to improve the quality of frozen-thawed (FT) spermatozoa for AI. (c) 2008 Elsevier B.V. All rights reserved.
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| 11. |
- Macias Garcia, B., et al.
(författare)
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Single-Layer Centrifugation Through Colloid Positively Modifies the Sperm Subpopulation Structure of Frozen-Thawed Stallion Spermatozoa
- 2009
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Ingår i: Reproduction in domestic animals. - : Wiley-Blackwell. - 0936-6768 .- 1439-0531. ; 44:3, s. 523-526
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Tidskriftsartikel (refereegranskat)abstract
- The present study attempted to select the subpopulation of stallion spermatozoa that best survived a conventional freezing and thawing procedure, using centrifugation of post-thawed semen samples through a single layer of a glycidoxypropyltrimethoxysilane-coated silica colloid with a species-specific formulation (Androcoll-E (TM)). After freezing and thawing, four sperm subpopulations were identified, listed as FT1 to FT4. While subpopulations FT1 and FT2 were characterized by low sperm velocity, high velocities characterized the ones called FT3 and FT4. The single-layer centrifugation (SLC)-handled sperm sample was enriched in subpopulation FT3, reaching a proportion of 82.6% of the present spermatozoa, in contrast with the non-filtered control post-thawed semen, where this sperm subpopulation only accounted for 16.3% of the total. It is concluded that in the equine industry, the SLC is a practical, easy-to-perform approach to improve the quality of equine frozen-thawed semen samples.
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| 12. |
- Mesa, JL, et al.
(författare)
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Anthropometric determinants of a clustering of lipid-related metabolic risk factors in overweight and non-overweight adolescents--influence of cardiorespiratory fitness. The Avena study
- 2006
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Ingår i: Annals of nutrition & metabolism. - : S. Karger AG. - 1421-9697 .- 0250-6807. ; 50:6, s. 519-527
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Tidskriftsartikel (refereegranskat)abstract
- <i>Background/Aims:</i> To explore in adolescents the associations between simple anthropometric variables with a continuously distributed summary score for lipid-related metabolic risk in both overweight and non-overweight adolescents, and to test whether these associations are modified by the level of cardiorespiratory fitness. <i>Methods:</i> Cardiorespiratory fitness, BMI, skinfold thicknesses, body circumferences, and a continuously distributed clustering of lipid- related metabolic risk (calculated from LDL and HDL choles- terol, triglycerides, and glucose) were measured in 524 adolescents (265 males, 259 females, 15.3 ± 1.4 years) from the cross-sectional multicentric AVENA study. Participants were classified as overweight (including obesity) or non-overweight. <i>Results:</i> Most anthropometric parameters were univariately related to the continuous lipid-related metabolic risk. However, after multicollinear analysis and generalized linear modelling, suprailiac skinfold thickness in males (p < 0.001, explained variance 12.2%) and waist-to-height ratio in females (p < 0.001, explained variance 10.0%) were the best determinants of the continuous metabolic risk score, after adjustment for age, sexual maturation, and economic status. These associations were slightly weakened in overweight males (p = 0.034) and females (p = 0.087), and did not interact with cardiorespiratory fitness. <i>Conclusion:</i> Our data emphasize the usefulness of suprailiac skinfold thickness in males and waist-to-height ratio in females as simple anthropometric measurements associated to an overall lipid-related metabolic risk, mainly in non-overweight adolescents and regardless their cardiorespiratory status.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Myrén, Niklas, et al.
(författare)
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Systems measurements of 2x2 poled fiber switch
- 2005
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Ingår i: IEEE Photonics Technology Letters. - 1041-1135 .- 1941-0174. ; 17:12, s. 2571-2573
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Tidskriftsartikel (refereegranskat)abstract
- The performance of a 2x2 all-fiber electrooptical switch is characterized in a system at up to 40 Gb/s. Error-free transmission is demonstrated. The device was also employed as a protection switch at 10 Gb/s in an installed fiber link.
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| 17. |
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| 18. |
- Ortega, Francisco B., et al.
(författare)
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Physically active adolescents are more likely to have a healthier cardiovascular fitness level independently of their adiposity status : the European youth heart study
- 2008
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Ingår i: Revista Española de Cardiología. - Amsterdam : Elsevier. - 0300-8932 .- 1579-2242. ; 61:2, s. 123-129
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Tidskriftsartikel (refereegranskat)abstract
- Introduction and objectives Cardiovascular fitness (CVF) has been considered a health marker at all ages. The main purpose of this study was to examine whether meeting the current physical activity (PA) recommendations is associated with a healthier CVF level in adolescents.Methods A total of 472 adolescents (14–16 years-old) were studied. CVF was estimated from a maximal bike test and PA was objectively assessed by accelerometry. Subjects were classed as high/low-CVF level, according to the Cooper Institute's cut-offs, and having a high/low-PA level depending on if the adolescents were engaged in at least 60 min per day at moderate-vigorous PA intensity level. Body fat was estimated from skinfold thicknesses.Results Binary logistic regression showed that adolescent girls meeting the current PA recommendations (≥60 min/day of moderate-vigorous PA) were 3 times more likely to have a high-CVF level than girls that did not meet the recommendations, after controlling for sexual maturation status (Tanner stages) and body fat. Likewise, adolescent boys meeting the PA recommendations were 8 times more likely to have a high-CVF level than boys that did not meet the recommendations.Conclusions The results suggest that devoting 60 min or more to moderate-vigorous PA daily is associated with a healthier CVF level in adolescents, independent of maturation status and adiposity. The patterns of the association were similar in girls and boys, but the fact that the associations were weaker in girls is of concern.
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| 19. |
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| 20. |
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| 21. |
- Ortega-Ferrusola, C., et al.
(författare)
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Apoptotic markers can be used to forecast the freezeability of stallion spermatozoa
- 2009
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Ingår i: Animal Reproduction Science. - : Elsevier Masson. - 0378-4320 .- 1873-2232. ; 114:4, s. 393-403
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Tidskriftsartikel (refereegranskat)abstract
- In an attempt to identify valuable markers for potential freezeability of the equine spermatozoa, three ejaculates were collected from five Andalusian stallions and frozen using a standard protocol. Before freezing, three apoptotic cell markers were studied by flow cytometry (early changes in sperm membranes, mitochondrial membrane potential and caspase activity). Post-thaw, spermatozoa were again evaluated for these parameters. Sperm kinematics using CASA were also studied before and after freezing and thawing. Receiving operating system curves were used to evaluate the relative value of the apoptotic markers herein studied, as forecast for potential freezeability. From all parameters studied, the outcome of JC-1 (as proportion of spermatozoa showing simultaneously orange and green fluorescence) had the highest diagnostic power. For potentially bad freezers (less than 25% of intact spermatozoa post-thaw), the significant area under the ROC-curve was 0.985, with a 100% sensitivity and 99.8% specificity for a cut off value of 55.7. (C) 2008 Elsevier B.V. All rights reserved.
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| 22. |
- Ortega-Ferrusola, C., et al.
(författare)
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Does the Microbial Flora in the Ejaculate Affect the Freezeability of Stallion Sperm?
- 2009
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Ingår i: Reproduction in domestic animals. - : Wiley-Blackwell. - 0936-6768 .- 1439-0531. ; 44:3, s. 518-522
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Tidskriftsartikel (refereegranskat)abstract
- In an attempt to evaluate the possible relationship between the microbial flora in the stallion ejaculate and its ability to freeze, three ejaculates from five stallions were frozen using a standard protocol. Before freezing, an aliquot was removed for bacteriological analysis. Bacterial growth was observed in all the ejaculates studied. The isolated microorganisms were: Staphylococcus spp. and Micrococcus spp. (in all the stallions), beta-haemolytic Streptococcus (in stallions 3 and 4), Corynebacterium spp. (in stallions 1, 3-5), Rhodococcus spp. (in stallion number 2), Pseudomonas spp. (in stallion number 1) and Klebsiella spp. (in stallions 1, 3 and 5). The presence and richness of Klebsiella and beta-haemolytic Streptococcus in the ejaculate were related to two sperm variables post-thaw, namely the proportion of dead spermatozoa (ethidium+ cells; r = 0.55, p less than 0.05) and the amplitude of lateral displacement of the sperm head (ALH, mu m; r = -0.56, p less than 0.05), respectively. The degree of growth of Corynebacterium spp. in the ejaculate was positively correlated with the percentage of spermatozoa showing high caspase activity post-thaw (r = 0.62, p less than 0.05). The presence and number of colonies of beta-haemolytic Streptococcus were negatively correlated (r = -0.55, p less than 0.05) with low sperm caspase activity. It is concluded that the microbial flora of the equine ejaculate may be responsible for some of the sublethal damage experimented by the spermatozoa during cryopreservation.
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| 23. |
- Ortega Ferrusola, C., et al.
(författare)
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Effect of Cryopreservation on Nitric Oxide Production by Stallion Spermatozoa
- 2009
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Ingår i: Biology of Reproduction. - : Society for the Study of Reproduction. - 0006-3363 .- 1529-7268. ; 81:6, s. 1106-1111
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Tidskriftsartikel (refereegranskat)abstract
- The ability of stallion spermatozoa to produce nitric oxide (NO) before (fresh) and after freezing and thawing (FT) was evaluated by means of flow cytometry after loading the sperm suspension with the probe, 4,5-diaminofluorescenin diacetate. The presence of NO synthase (NOS) was investigated by Western blotting using anti-NOS1, anti-NOS3, or anti-universal NOS antibodies (Abs). While NO was detected both in fresh and FT sperm suspensions, its production increased after cryopreservation only when egg yolk was removed from the extender. Anti-NOS1 Ab intensively labeled a single band with an apparent molecular mass of approximately 83 kDa. On the other hand, the Ab developed against the NOS3 showed a band of approximately 96 kDa in fresh and FT sperm lysates. NO production was positively correlated with sperm motility and velocity after thaw, suggesting an NO role for the functionality of cryopreserved stallion spermatozoa; but the production of NO is compromised in egg yolk-containing extenders.
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| 24. |
- Ortega-Ferrusola, C., et al.
(författare)
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Identification of Sperm Subpopulations in Stallion Ejaculates: Changes after Cryopreservation and Comparison with Traditional Statistics
- 2009
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Ingår i: Reproduction in domestic animals. - : Wiley-Blackwell. - 0936-6768 .- 1439-0531. ; 44:3, s. 419-423
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Tidskriftsartikel (refereegranskat)abstract
- In an attempt to improve the information obtained after computer-assisted sperm analysis (CASA), data from five stallions (three ejaculates from each) were analysed before (fresh, extended semen) and after cryopreservation using traditional statistics as well as a cluster analysis. The data matrix consisted of 13 987 observations of individual spermatozoa for fresh, extended semen, and 8305 for frozen-thawed samples. As expected, freezing and thawing resulted in a marked decrease of CASA-derived variables of sperm kinematics. All sperm velocities were significantly lower in frozen-thawed samples than in samples before cooling. Using sperm velocities, six sperm subpopulations were identified in fresh semen (S1-S6). As such, subpopulations S1 and S2 were characterized by low sperm velocities, subpopulations S3 and S4 corresponded to spermatozoa depicting medium speed values, and finally, subpopulations S5 and S6 were those depicting the highest velocities. After freezing and thawing, four sperm subpopulations were identified, listed as nr FT1 to FT4. While subpopulations FT1-FT3 were characterized by low sperm velocities, and thus corresponded speed-wise to those listed as S1-S4 for fresh, extended semen, the one called number FT4 in frozen semen was characterized by high velocities, of the same range as that of the subpopulations S5 and S6 for fresh spermatozoa. The sperm subpopulation structure varied among stallions, but the cluster analysis hereby assayed was able to provide valuable information about the freezability of the samples that the customary statistics did not reveal.
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| 25. |
- Ortega Ferrusola, C., et al.
(författare)
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Lipid peroxidation, assessed with BODIPY-C-11, increases after cryopreservation of stallion spermatozoa, is stallion-dependent and is related to apoptotic-like changes
- 2009
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Ingår i: Reproduction. - : BioScientifica. - 1470-1626 .- 1476-3990. ; 138:1, s. 55-63
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Tidskriftsartikel (refereegranskat)abstract
- Lipid peroxidation (LPO) of stallion spermatozoa was assessed in fresh semen and in samples of the same ejaculates after freezing and thawing. Particular attention was paid to individual differences in the susceptibility to LPO and its possible relationship with freezability. Innate levels of LPO were very low in fresh spermatozoa but increased after thawing, a change that was largely stallion-dependent. The level of LPO in fresh spermatozoa was not correlated with that of the thawed spermatozoa. Negative correlations existed between LPO and intact membranes post-thaw (r= -0.789, Pless than0.001), and also between LPO and spermatozoa with high mitochondrial membrane potential (Delta psi m) post-thaw (r= -0.689, Pless than0.001). LPO was also highly and significantly correlated with caspase activity. The correlation between caspase activity in ethidium positive cells and LPO was r=0.772, Pless than0.001. This LPO is unlikely to represent, per se, a sign of cryopreservation-induced injury, but it is apparently capable of triggering apoptotic-like changes that could result in the sub-lethal cryodamage often seen among surviving spermatozoa. Reproduction (2009) 138 55-63
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| 26. |
- Ortega Porcel, Francisco B
(författare)
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Physical activity, cardiovascular fitness and abdominal adiposity in children and adolescents
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cardiovascular fitness (CVF) and adiposity, especially abdominal adiposity, are well-known factors associated with general health status in childhood and adolescents. Physical activity (PA) may play a crucial role in CVF enhancement and the prevention of abdominal adiposity accumulation. The apparently obvious association of PA with CVF and adiposity still requires further research, since current knowledge is mostly based on data from self-reported measures but such measures are of limited use in pediatric populations. The current thesis aimed to examine the associations of objectively measured PA with CVF and abdominal adiposity in more than one thousand children (9-10 years) and adolescents (15-16 years) from the Swedish part of the European Youth Heart Study. Total PA levels and time spent in PA of different intensities (i.e. moderate and vigorous PA) were measured by accelerometry. Cardiovascular fitness was measured by a maximal cycling test. Body mass index was used to define overweight/obesity, and waist circumference to define an excess of central adiposity. Percentage body fat was estimated from skinfold thickness. Stages of sexual maturation were identified according to Tanner. The main findings and conclusions were: I) When examining CVF in adolescents, sexual maturation status and percentage body fat, as well as the way in which CVF is expressed, should be taken into account. II) Those adolescents who spend 60 minutes or more in moderate to vigorous PA daily seem to be more likely to have a healthier CVF level, independently of their sexual maturation and adiposity status. III) Low levels of total PA and, in particular, of vigorous PA, are associated with an increased risk for overweight and excess of central adiposity, independently of other important determinant factors, such as television viewing and birth weight. The data also indicate that the adverse association of television viewing with abdominal adiposity could be attenuated if sufficient vigorous PA is accumulated. IV) Cardiovascular fitness is inversely associated with abdominal adiposity and seems to modify the associations between PA and abdominal adiposity. In children and adolescents with low CVF, time spent in vigorous PA seems to be the key component linked to abdominal adiposity. The findings reported in this thesis will contribute to a better understanding of the associations of PA with CVF and abdominal adiposity, a prerequisite for more efficient health promotion. Future public health recommendations should consider the evidence-based importance of high intensity PA.
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| 27. |
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| 28. |
- Rizzo, Nico S., et al.
(författare)
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Relationship of physical activity, fitness, and fatness with clustered metabolic risk in children and adolescents : the European youth heart study
- 2007
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Ingår i: The Journal of Pediatrics. - St. Louis, Mo : Mosby. - 0022-3476 .- 1097-6833. ; 150:4, s. 388-394
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To examine the associations of physical activity (PA) at different levels and intensities and cardiorespiratory fitness (CRF) with a clustering of metabolic risk factors in children and adolescents with special consideration of body fat. Study design Total PA and intensity levels were measured by accelerometry in children (9 years, n = 273) and adolescents (15 years, n = 256). CRF was measured with a maximal ergometer bike test. Measured outcomes included fasting insulin, glucose, triglycerides, total and high-density lipoprotein cholesterol, blood pressure, and body fat. A metabolic risk score (MRS) was computed as the mean of the standardized outcome scores. A “non-obesity-MRS” was computed omitting body fat from the MRS. Analysis of variance and multiple regressions were used in the analysis. Results Total and vigorous PA was inversely significantly associated with MRS in adolescent girls, the group with lowest PA, becoming insignificant when CRF was introduced in the analysis. Significant regression coefficients of total PA and CRF on non-obesity–MRS diminished when body fat was entered in the analysis. Conclusions CRF is more strongly correlated to metabolic risk than total PA, whereas body fat appears to have a pivotal role in the association of CRF with metabolic risk.
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| 29. |
- Ruiz, Jonatan R., et al.
(författare)
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High cardiovascular fitness is associated with low metabolic risk score in children : the European Youth Heart Study
- 2007
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Ingår i: Pediatric Research. - Baltimore, Md : Williams and Wilkins Co. - 0031-3998 .- 1530-0447. ; 61:3, s. 350-355
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to examine the associations of cardiovascular fitness (CVF) with a clustering of metabolic risk factors in children, and to examine whether there is a CVF level associated with a low metabolic risk. CVF was estimated by a maximal ergometer bike test on 873 randomly selected children from Sweden and Estonia. Additional measured outcomes included fasting insulin, glucose, triglycerides, HDLC, blood pressure, and the sum of five skinfolds. A metabolic risk score was computed as the mean of the standardized outcomes scores. A risk score <75th percentile was considered to indicate a low metabolic risk. CVF was negatively associated with clustering of metabolic risk factors in children. Receiver operating characteristic curve analysis showed a significant discriminatory accuracy of CVF in identifying the low/high metabolic risk in girls and boys (p < 0.001). The CVF level for a low metabolic risk was 37.0 and 42.1 mL/kg/min in girls and boys, respectively. These levels are similar to the health-related threshold values of CVF suggested by worldwide recognized organizations. In conclusion, the results suggest a hypothetical CVF level for having a low metabolic risk, which should be further tested in longitudinal and/or intervention studies. Abbreviations: AUC, area under the curve CVF, cardiovascular fitness ROC, receiver operating characteristic
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| 30. |
- Ruiz, Jonatan R., et al.
(författare)
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Homocysteine levels in children and adolescents are associated with the methylenetetrahydrofolate reductase 677C>T genotype, but not with physical activity, fitness or fatness : the European Youth Heart Study
- 2007
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Ingår i: British Journal of Nutrition. - Cambridge : Cambridge university press. - 0007-1145 .- 1475-2662. ; 97:2, s. 255-262
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Tidskriftsartikel (refereegranskat)abstract
- To examine the associations of total plasma homocysteine (tHcy) with physical activity, cardiorespiratory fitness and fatness in children and adolescents, a cross-sectional study of 301 children (9–10 years old) and 379 adolescents (15–16 years old) was conducted. Physical activity was measured by accelerometry. Cardiorespiratory fitness was measured with a maximal ergometer bike test. Body fat was derived from the sum of five skinfold thicknesses. Genotyping for the methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism was done by DNA sequencing. Fasting tHcy level was the outcome variable. Multiple regressions were used to determine the degree to which variance in tHcy was explained by physical activity, cardiorespiratory fitness and body fat, after controlling for potential confounders including MTHFR 677C>T genotype. tHcy levels were neither associated with any measure of level and pattern of physical activity nor with data on cardiorespiratory fitness, or body fat, in any age group after controlling for potential confounders including MTHFR 677C>T and even when subgroups 677TT and 677CC+CT were analysed separately. Mean values of tHcy were significantly higher in the TT subgroup compared with CC and CT subgroups in children (TT 7·4 μmol/l, CC 6·3 μmol/l, CT 6·6 μmol/l, P < 0·001 and P = 0·019, respectively) and adolescents (TT 16·9 μmol/l, CC 8·3 μmol/l, CT 9·0 μmol/l, both P < 0·001). The results suggest that physical activity, fitness and body fat are not associated with tHcy levels in children and adolescents, even after controlling for presence of the MTHFR 677C>T genotype, the main influence on tHcy levels in these subjects.
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| 31. |
- Ruiz, Jonatan R., et al.
(författare)
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Relations of total physical activity and intensity to fitness and fatness in children : the European Youth Heart Study
- 2006
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 84:2, s. 299-303
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is unclear how the amount and intensity of physical activity (PA) are associated with cardiovascular fitness (CVF) and body fatness in children.Objective: We aimed to examine the associations of total PA and intensity levels to CVF and fatness in children.Design: A cross-sectional study of 780 children aged 9–10 y from Sweden and Estonia was conducted. PA was measured by accelerometry and was expressed as min/d of total PA, moderate PA, and vigorous PA. CVF was measured with a maximal ergometer bike test and was expressed as W/kg. Body fat was derived from the sum of 5 skinfold-thickness measurements. Multiple regression analysis was used to determine the degree to which variance in CVF and body fat was explained by PA, after control for age, sex, and study location.Results: Lower body fat was significantly associated with higher levels of vigorous PA, but not with moderate or total PA. Those children who engaged in >40 min vigorous PA/d had lower body fat than did those who engaged in 10–18 min vigorous PA/d. Total PA, moderate PA, and vigorous PA were positively associated with CVF. Those children who engaged in >40 min vigorous PA/d had higher CVF than did those who accumulated <18 min vigorous PA/d.Conclusions: The results suggest that PA of vigorous intensity may have a greater effect on preventing obesity in children than does PA of lower intensity, whereas both total and at least moderate to vigorous PA may improve children's CVF.
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| 32. |
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| 33. |
- Sjöström, Michael, et al.
(författare)
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The European Youth Heart Study (EYHS)
- 2006
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Ingår i: EUROPEAN JOURNAL OF PUBLIC HEALTH. - 1101-1262. ; 16, s. 22-22
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Konferensbidrag (refereegranskat)
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| 34. |
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