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161.
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?相似文献   
162.
This study examined the influence of the regression model and initial intensity of an incremental test on the relationship between the lactate threshold estimated by the maximal-deviation method and the endurance performance. Sixteen non-competitive, recreational female runners performed a discontinuous incremental treadmill test. The initial speed was set at 7 km · h?1, and increased every 3 min by 1 km · h?1 with a 30-s rest between the stages used for earlobe capillary blood sample collection. Lactate-speed data were fitted by an exponential-plus-constant and a third-order polynomial equation. The lactate threshold was determined for both regression equations, using all the coordinates, excluding the first and excluding the first and second initial points. Mean speed of a 10-km road race was the performance index (3.04 ± 0.22 m · s?1). The exponentially-derived lactate threshold had a higher correlation (0.98 ≤ r ≤ 0.99) and smaller standard error of estimate (SEE) (0.04 ≤ SEE ≤ 0.05 m · s?1) with performance than the polynomially-derived equivalent (0.83 ≤ r ≤ 0.89; 0.10 ≤ SEE ≤ 0.13 m · s?1). The exponential lactate threshold was greater than the polynomial equivalent (P < 0.05). The results suggest that the exponential lactate threshold is a valid performance index that is independent of the initial intensity of the incremental test and better than the polynomial equivalent.  相似文献   
163.
To elucidate a higher rate of premature cardiovascular disease (CVD) in Asian Indian descendants (Roma) in Slovakia, we investigated frequency distribution, correlates and relationship of lipoprotein(a) [Lp(a)] to family CVD risk factors in Roma children and their Caucasian neighbors. The study sample consisted of 607 healthy children aged 7–18 years (55% Roma, 48% male) as part of the biracial (Roma–Caucasian) Slovak Lipid Community Study. Overall, frequency distribution data of Lp(a) were highly skewed to low concentrations, with markedly higher Lp(a) levels in Roma than in Caucasian children (median and range, mg/dL: 14.5; 0–159.2 vs 6.2; 0–112.3, P < 0.001), regardless of age and gender. Lp(a) was positively correlated with apo B (0.159, P = 0.004) in Roma, and LDL cholesterol (0.170, P = 0.005) in Caucasian children. In addition, daily income of the family was negatively related with Lp(a) in Roma (−0.134, P = 0.036) while positively in Caucasians (0.136, P = 0.047). For both race groups, no significant association was found between Lp(a) and age, body mass index, mean arterial pressure, smoking, and physical activity. Also, no significant relationships were examined between serum Lp(a) levels >30 mg/dL in children and family CVD risk factors, except for diabetes mellitus in parents of Caucasian origin (OR 4.46; 95%CI: 1.23–16.20). In a multivariate analysis, daily income, LDL cholesterol or apo B explained ~7% of the variance of Lp(a). This study suggests a significantly higher serum Lp(a) levels in Roma than in Caucasian children and a small effect, in general, of relevant CVD risk factors on the variation of Lp(a) levels in childhood.  相似文献   
164.
In this work, the effect of different treatments over the adherence of ultrahigh molecular weight polyethylene (UHMWPE) to a composite material (epoxy/fibreglass), used as base and core of snowboards, respectively, was studied. The selected treatments were flame treatment, ultraviolet (UV) treatment and abrasion. Adhesion was assessed using lap shear tests. The results showed an increase in UHMWPE/composite adhesion of over six times with flame treatment, and a considerably lower increase with the abrasion. No increase in adhesion was detected with UV treatment. Scanning electron microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry tests were performed to explain these changes.  相似文献   
165.
We review empirical research on English language learners (ELLs) who struggle with reading and who may have learning disabilities (LD). We sought to determine research indicators that can help us better differentiate between ELLs who struggle to acquire literacy because of their limited proficiency in English and ELLs who have actual LD. We conclude that more research is warranted to further elucidate the strengths and learning needs of subgroups of underachieving ELLs, to help us determine who should qualify for special education, and to clarify why some ELLs who do not have LD still struggle with language and literacy acquisition. Future research should account for the complexities involved in becoming literate in another language and focus more on cultural and contextual factors that affect student achievement.  相似文献   
166.
In this paper a generalisation of the h-index and g-index is given on the basis of non-negative real-valued functionals defined on subspaces of the vector space generated by the ordered samples. Several Hirsch-type measures are defined and their basic properties are analysed. Empirical properties are illustrated using examples from the micro- and meso-level. Among these measures, the h-index proved the most, the arithmetic and geometric g-indices, the least robust measures. The μ-index and the harmonic g-index provide more balanced results and are still robust enough.  相似文献   
167.
Twenty-four university students with disabilities were interviewed about their experiences studying at Czech universities. The interviews were analysed using the grounded theory approach. The most commonly experienced barriers faced by these students were institutional barriers, attitudinal barriers, and disability-specific barriers. The types of support mentioned by the students included family support, peer support, and support provided by assistants. The participants also shared strategies they used to deal with the barriers they faced. These were assertiveness, self-determination, metacognition, efforts to ‘fit in’, optimism, and career planning. The implications for policy and universities are discussed.  相似文献   
168.
169.
Over the past several decades, the Latino population throughout the USA has demonstrated significant growth and exceeded that of other ethnic minority groups. This influx is particularly evident in the student enrollment of US schools as the number of Latino students has increased by approximately 10 million within the past 10 years. With this dramatic increase, there are a number of critical issues that present significant barriers to a high-quality educational experience for Latino students, specifically overrepresentation of Latinos receiving disciplinary actions and the high number of referrals to special education evaluation for emotional and behavioral disorders. This paper will discuss the impact of the Latino population in US schools, the concern of overrepresentation and biased referrals, and the use of a culturally attuned functional behavioral assessment as a pragmatic solution to better serve this growing population.  相似文献   
170.

As is now widely established, sexuality is a historically and culturally specific social construction. In Mexico, such construction has been dominated by different institutions and discourses at different times. From pre-Hispanic times to today, this article traces the ideas that main institutions, like the Catholic Church, have ingrained in Mexican sexual culture and shows how they have changed over time. At present, sexuality has become a contested arena?like never before?in which very diverse discourses contend for hegemony. Formal sex education has not been alien to this debate, in which religion, medicine, gender equity discourses and ethics seem to have a differential input in curricula and textbooks. This article discusses the expression of this tension in formal sex education in Mexico.  相似文献   
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