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Domestic cats are capable of leading both solitary and social lives and socializing to humans. This type of socialization may also enhance an animal's problem-solving ability. We examined the relationship between socialization and problem-solving ability, problem-solving speed, and latency to approach a novel apparatus in domestic cats. Socialization towards humans was measured with the Feline Behavior Assessment based on the ASPCA's Feline Spectrum Assessment. This modified measure requires assessors to observe an individual cat's behavior during three steps: observation test, door test, and the stroke and push test. During each test, the assessor examined specific behaviors that are indicative of socialization. Problem solving was assessed with a food-acquisition puzzle box that required the subject to pull on a tab to release a food reward. Twenty-four out of eighty-six cats solved the problem-solving task. More socialized cats were more likely to solve the problem, solve it faster, and approach the apparatus sooner. We also found a significant relationship between age and problem solving; younger adult cats were more likely to solve the problem than older adults. These results provide evidence that domestic cats are not only capable of solving this type of problem but also that their socialization towards humans influences their abilities.

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The study investigates relative age effects (RAE) in German youth soccer (Youth Bundesliga A: January 2004 to December 2005 and B: January 2006 to December 2007; highest league in German youth soccer) and its persistence in third-division players. Data from the 2022-2023 season (120 teams, 3,174 players) were analyzed using chi-square tests. Significant RAE was found in the A-series (p < .001), B-series (p < .001), and third-division professionals (p < .001). Notably, RAE was prominent among younger players but less evident in older third-division players (p = .116), indicating a diminishing selection effect with age and professional tenure. Coaches and talent managers are advised to consider RAE and additional factors like player maturity in talent selection for more efficient talent management strategies, especially in youth academies.

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OBJECTIVES: Previous studies and theories show that healthy lifestyles are affected by life chances and subjective perceptions. However, it remains unclear how older adults change between different lifestyle profiles as they age. We proposed the healthy lifestyle duality framework and tested it among older Chinese adults using a longitudinal design. METHODS: Data were obtained from 4 Chinese Longitudinal Healthy Longevity Surveys conducted between 2008 and 2018 (N = 31,445). Latent transition analysis and hierarchical multinomial growth curve models were performed to investigate healthy lifestyle profiles and their associations with life chances and subjective perceptions over time. RESULTS: Four distinct healthy lifestyle profiles were identified: healthy, risky, low-standard, and mixed groups, and their changes show path dependency. Across 10 years, the proportion of the healthy group ranged from 11.16% to 16.97%. Both life chances and subjective perceptions were longitudinally associated with healthy lifestyles, with age and cohort effects observed. DISCUSSION: Our findings support the healthy lifestyle duality framework and reveal that life chances and subjective perceptions influence lifestyle changes over time. Public health policies and health intervention programs should adapt to the specific needs of different age groups and generations.

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OBJECTIVES: Inter-individual developmental differences confound the capability to accurately evaluate youth athletic performance, highlighting the need for considerate methodology and analytical approaches. The present study demonstrated how Percentile Comparison Methods (PCMs) were developed, tested, and applied to identify athlete developmental profiles in Australian youth swimming. DESIGN: Cross-sectional. METHODS: Participants were N = 866 female 100-metre (m) Front-Crawl swimmers, aged 9-15 years, competing at 36 Australian regional-national level long course events. At respective events, swim performance time was collated alongside, age, date of birth, and anthropometric measures to identify age group, relative age, and maturity status. Quadratic relative age and maturity status with 100-m performance regression trendlines were generated. Then, individual swim performances at a given relative age or maturity status were converted into percentile rank distributions and compared with raw (unadjusted) annual age-group performance percentile ranks. RESULTS: At a cohort level, initial testing confirmed relative age and maturity-adjusted percentile rankings were associated with general rank improvements for relatively younger and later maturing swimmers compared to raw ranks (and vice versa). When assessing individual swimmer plots, where three percentile rank scores were compared and rank change threshold criteria applied, five Percentile Comparison Method profile types were identified, namely: 'Early Developing' (19 %); 'Later Developing' (18 %); 'Consistent' (15 %); 'Mixed' (38 %) and 'Counteracting' (10 %). Percentile Comparison Method plots helped identify developmentally (dis-)advantaged swimmers; specific factors leading to (dis-)advantage, and likely onward development trajectories. CONCLUSIONS: Overall and with practical considerations, Percentile Comparison Methods can improve the validity of youth athletic performance evaluation as well as inform athlete development programming.

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Despite growing concerns in the UK about social isolation, there remains a lack of data on the extent and time trends of social isolation from longitudinal, population-based studies. There is also little research that assesses the multiple domains of social isolation across the lifecourse and between generations in a holistic way accounting for different contexts. By applying a multi-context, multi-domain framework of social isolation to 5 successive British birth cohorts, we provide conceptual and empirical understanding of social isolation trajectories across the lifecourse and identify potential generational and sex differences in trends. Where data were available, comparable social isolation indicators were generated to enable lifecourse trajectories and cross-generational trends to be explored. Information on isolation was available across the following relational contexts: household i.e., living alone; partnership, family and friends outside the household; education and employment networks; and community engagement. Trajectories were modelled stratified by sex using a multilevel growth curve framework. Data were analysed from 73,847 individuals (48.5% female), in 5 successive cohorts born in 1946 (N = 5,362), 1958 (N = 16,742), 1970 (N = 16,950), 1989-90 (N = 15,562), and 2000-01 (N = 19,231). Exploring a range of social isolation indicators across several contexts provided a nuanced picture of social isolation across the lifecourse and between generations in the UK, with no consistent pattern of increased or decreased isolation over time. For example, more people are living alone, less women are out of education and employment in midlife, more people are volunteering, but fewer people regularly engage in religious activity. It therefore highlights the need to focus on a range of social isolation indicators across contexts to understand how people compensate for specific types of isolation, and to understand structural differences in social configurations in the UK, which may not only define the timing and sequencing of life transitions but also social isolation.

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Soccer organizations generally adopt deterministic models within their talent pathways. In this framework, early ability and results are emphasized, leading to selection biases, such as birth advantages (i.e., relative age effects and birthplace effects), which research has shown affect both early developmental experiences and continued sporting involvement. Accordingly, this study aimed to (a) provide further test of birth advantages in Italian youth soccer by exploring the birth quarter (BQ) and birthplace (BP) distribution of 1050 male Italian players born between 1999 and 2001 who competed in the national U17 championship throughout the 2015-16 season and (b) investigate how birth advantages influenced selected players' future career status. Chi-square goodness-of-fit tests revealed early born players, and players born in North Italy were overrepresented at the youth level (p-values < 0.0001). Successive prospective analysis revealed only 18% of players developed into professional-level soccer players. Chi-square tests of independence indicated that players' BP was associated with their future career status (p < 0.0001), whereas their BQ was not (p = 0.459). Odds ratios showed players born in North Italy were five times more likely to complete the youth-to-senior transition than those born in South Italy. These findings highlighted environmental factors influence Italian players' early developmental experiences and their future career status.

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BACKGROUND: Psychological treatments for young people with sub-threshold or full-syndrome borderline personality disorder (BPD) are found to be effective. However, little is known about the age at which adolescents benefit from early intervention. This study investigated whether age affects the effectiveness of early intervention for BPD. METHODS: N = 626 participants (M age = 15 years, 82.7% female) were consecutively recruited from a specialized outpatient service for early intervention in BPD in adolescents aged 12- to 17-years old. DSM-IV BPD criteria were assessed at baseline, one-year (n = 339) and two-year (n = 279) follow-up. RESULTS: Older adolescents presented with more BPD criteria (χ2(1) = 58.23, p < 0.001) and showed a steeper decline of BPD criteria over the 2-year follow-up period compared with younger adolescents (χ2(2) = 13.53, p = 0.001). In an attempt to disentangle effects of early intervention from the natural course of BPD, a parametrized regression model was used. An exponential decrease (b = 0.10, p < 0.001) in BPD criteria was found when starting therapy over the 2-year follow-up. This deviation from the natural course was impacted by age at therapy commencement (b = 0.06, p < 0.001), although significant across all ages: older adolescents showed a clear decrease in BPD criteria, and young adolescents a smaller decrease. CONCLUSIONS: Early intervention appears effective across adolescence, but manifests differently: preventing the normative increase of BPD pathology expected in younger adolescents, and significantly decreasing BPD pathology in older adolescents. The question as to whether developmentally adapted therapeutic interventions could lead to an even increased benefit for younger adolescents, should be explored in future studies.

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OBJECTIVES: Standardized bite training is required to prevent oral hypofunction in elderly individuals. We aimed to compare masticatory muscle activity between 24 young adults and 16 pre-elderly individuals during a biting task using a novel standardized bite device (BD). METHODS: The BD was made of silicone rubber and included a high-force or low-force plate spring or no plate spring (dummy). The compressive stiffness of the material in each BD was measured using a texture analyzer. All participants performed a biting task 50-times at a rate of 1/s each using the three types of BDs on the right first molar. Electromyographic (EMG) activity was recorded bilaterally from the masseter and temporalis muscles. The variability of each biting training session was calculated as the coefficient of variance (CV) from the EMG activity during each biting task for each muscle. Masticatory muscle fatigue was assessed using a numerical rating scale (NRS). RESULTS: Compressive stiffness was significantly different between each BD (P < 0.001). The CV and NRS scores were not significantly different between the groups. The EMG activities during each bite task in all muscles were not significantly different for any measurement item between the age groups. The EMG activities of high- and low-force BDs in the right temporalis (ipsilateral) muscle were significantly higher than those of the dummy BD (P < 0.001). CONCLUSIONS: Compressive stiffness of the BD affected EMG activity only in the ipsilateral temporalis muscle, but not in the masseter or contralateral temporalis muscles, without any age effect.

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Relative age effects (RAEs) are commonly associated with advantages for older athletes. However, a variety of benefits attributed to 'advantage reversals' have been observed among relatively younger professional athletes. Considering psychosocial development as a proposed mechanism, the purpose of this study was twofold: (1) To explore an association between developmental assets (i.e., facilitators of positive youth development [PYD]) and RAEs; (2) To assess whether overall developmental asset levels are protective against sport dropout. The Developmental Assets Profile© was distributed to members of a one-year cohort of post-adolescent, female soccer players from Ontario, Canada. The presence of differences between groups of relatively older (H1; n = 64) and younger (H2; n = 57) participants and developmental asset scales were assessed using discriminant analysis. A binary logistic regression was conducted to assess whether overall developmental asset levels are protective against sport dropout, with consideration of relevant factors. Findings suggest that relatively younger, female players score higher in two internal categories: commitment to learning and positive values. The overall developmental asset scores were not found to be protective against dropout. This study provides preliminary, albeit cautious, support that 'advantage reversals' may be in part associated with enhanced PYD resulting from developmental sport experiences.

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Recent outbreaks of various infectious diseases have highlighted the ever-present need to understand the drivers of the outbreak and spread of disease. Although much of the research investigating diseases focuses on single infections, natural systems are dominated by multiple infections. These infections may occur simultaneously, but are often acquired sequentially, which may alter the outcome of infection. Using waterfleas (Daphnia magna) as a model organism, we examined the outcome of sequential and simultaneous multiple infections with 2 microsporidian parasites (Ordospora colligata and Hamiltosporidium tvaerminnensis) in a fully factorial design with 9 treatments and 30 replicates. We found no differences between simultaneous and sequential infections. However, H. tvaerminnensis fitness was impeded by multiple infection due to increased host mortality, which gave H. tvaerminnensis less time to grow. Host fecundity was also reduced across all treatments, but animals infected with O. colligata at a younger age produced the fewest offspring. As H. tvaerminnensis is both horizontally and vertically transmitted, this reduction in offspring may have further reduced H. tvaerminnensis fitness in co-infected treatments. Our findings suggest that in natural populations where both species co-occur, H. tvaerminnensis may evolve to higher levels of virulence following frequent co-infection by O. colligata.

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Emergentism provides a framework for understanding how language learning processes vary across developmental age and linguistic levels, as shaped by core mechanisms and constraints from cognition, entrenchment, input, transfer, social support, motivation, and neurology. As our commentators all agree, this landscape is marked by intense variability arising from the complexity. These mechanisms interact in collaborative and competitive ways during actual moments of language use. To better understand these interactions and their effects, we need much richer longitudinal data regarding both input and output during actual contexts of usage. We believe that modern technology can eventually provide this data (Flege & Bohn, 2021) in ways that will allow us to more fully populate an emergent landscape.

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The effect of parental age on germline mutation rate across generations is not fully understood. While some studies report a positive linear relationship of mutation rate with increasing age, others suggest that mutation rate varies with age but not in a linear fashion. We investigated the effect of parental age on germline mutations by generating replicated mutation accumulation lines in Caenorhabditis remanei at three parental ages ("Young T1" [Day 1], "Peak T2" [Day 2], and "Old T5" [Day 5] parents). We conducted whole-genome resequencing and variant calling to compare differences in mutation rates after three generations of mutation accumulation. We found that Peak T2 lines had an overall reduced mutation rate compared to Young T1 and Old T5 lines, but this pattern of the effect varied depending on the variant impact. Specifically, we found no high-impact variants in Peak T2 lines, and modifiers and up- and downstream gene variants were less frequent in these lines. These results suggest that animals at the peak of reproduction have better DNA maintenance and repair compared to young and old animals. We propose that C. remanei start to reproduce before they optimize their DNA maintenance and repair, trading the benefits of earlier onset of reproduction against offspring mutation load. The increase in offspring mutation load with age likely represents germline senescence.

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Background and objective Facial fractures represent a growing concern among an aging population prone to falls. In light of this, this study aimed to investigate differential facial fracture patterns and outcomes based on age effects. Determining the differences between the severity and type of facial fractures in populations of different ages will help guide clinical decision-making when managing patients with facial fractures. Methods This was a single-center study involving trauma registry data, from July 1, 2016, to January 31, 2022. The inclusion criteria were based on the International Classification of Diseases (ICD-10) diagnosis of facial fracture. A linear regression was performed to ascertain the effects of predictor variables on the likelihood that a facial fracture trauma patient would experience various age effects on injury location, mortality, and morbidity. Results A total of 1575 patients were included in the analysis. A significant regression equation was found (F(47,1476)=42.46, p<0.01), with an R2 of 0.57. Older facial fracture trauma patients were more likely to be female (ß=3.13, p<0.01) with fractures to their zygoma (ß=2.57, p=0.02). Higher Abbreviated Injury Scale (AIS) facial region scores (ß=2.21, p=0.03), longer hospital length of stay (ß=0.07, p=0.02), and in-hospital mortality (ß=10.47, p<0.01) were also associated with older age. Older age was additionally associated with a higher level of several morbidity markers. Younger facial fracture trauma patients were more likely to be African American (ß=-5.46, p<0.01) or other, non-Caucasian race (ß=-8.66, p<0.01) and to have mandible fracture patterns (ß=-3.63, p<0.01). The younger patients were more likely to be fully activated (ß=-3.10, p<0.01) with a higher shock index ratio (SIR) (ß=-7.36, p<0.01). Injury mechanisms in younger facial fracture patients were more likely to be assault (ß=-12.43, p<0.01), four-wheeler/ATV accident (ß=-24.80, p<0.01), gunshot (ß=-15.18, p<0.01), moped accident (ß=-13.50, p<0.01), motorcycle accident (ß=-12.31, p<0.01), motor vehicle accident (ß=-16.52, p<.01), or pedestrian being struck by a motor vehicle (ß=-10.69, p=0.02). Conclusions Based on our findings, age effects impact facial fracture patterns and outcomes. Younger patients are more likely to experience multisystem injuries via non-fall trauma. On the other hand, older patients are more likely to experience more severe primary facial injuries. Older patients are also at a higher risk of fall-related trauma. Disparities also exist between genders and races, with male and non-Caucasian patients being at a higher risk of injury from facial fractures at a younger age. With an aging population, the prevalence of falls is likely to increase. Thus, facial fractures represent a growing healthcare burden and warrant future investments related to care and treatment.

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Introduction: Accelerometry has become increasingly prevalent to monitor physical activity due to its low participant burden, quantitative metrics, and ease of deployment. Physical activity metrics are ideal for extracting intuitive, continuous measures of participants' health from multiple days or weeks of high frequency data due to their fairly straightforward computation. Previously, we released an open-source digital health python processing package, SciKit Digital Health (SKDH), with the goal of providing a unifying device-agnostic framework for multiple digital health algorithms, such as activity, gait, and sleep. Methods: In this paper, we present the open-source SKDH implementation for the derivation of activity endpoints from accelerometer data. In this implementation, we include some non-typical features that have shown promise in providing additional context to activity patterns, and provide comparisons to existing algorithms, namely GGIR and the GENEActiv macros. Following this reference comparison, we investigate the association between age and derived physical activity metrics in a healthy adult cohort collected in the Pfizer Innovation Research Lab, comprising 7-14 days of at-home data collected from younger (18-40 years) and older (65-85 years) healthy volunteers. Results: Results showed that activity metrics derived with SKDH had moderate to excellent ICC values (0.550 to 1.0 compared to GGIR, 0.469 to 0.697 compared to the GENEActiv macros), with high correlations for almost all compared metrics (>0.733 except vs GGIR sedentary time, 0.547). Several features show age-group differences, with Cohen's d effect sizes >1.0 and p-values < 0.001. These features included non-threshold methods such as intensity gradient, and activity fragmentation features such as between-states transition probabilities. Discussion: These results demonstrate the validity of the implemented SKDH physical activity algorithm, and the potential of the implemented PA metrics in assessing activity changes in free-living conditions.

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We evaluated age effects in the Wechsler Abbreviated Scale of Intelligence-Second Edition (WASI-II) standardization sample. This extends work completed using previous editions of the Wechsler Adult Intelligence Scales. Of the four subtests, Vocabulary (VC) and Similarities (SI) were most resistant to aging. VC showed minimal variation regardless of age; SI peaked at 30 to 54 years followed by a decline. Block Design (BD) and Matrix Reasoning (MR) showed substantial drops from the younger to older groups. BD peaked at 17 to 44 years and then declined; MR peaked at 20 to 29 years and then consistently deteriorated. The WASI-II Verbal Comprehension Index peak at 30 to 44 years was followed by a maximum drop at 85 to 90 years. The Perceptual Reasoning Index peaked at 20 to 29 years, with a marked decline by 65 to 69 years. The Full Scale IQ was average until age 65 years followed by a decline. Minor changes in points of peak performance and subsequent decline were seen as a function of Full Scale IQ level. Results were consistent with crystallized and fluid intelligence theory.

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The current study is the first meta-analysis to examine grey matter volume (GMV) changes in adolescents and across the lifespan in major depressive disorder (MDD). Seed-based d mapping-with permutation of subject images (SDM-PSI) has advantages over previous coordinate-based meta-analytical methods (CBMA), such as reducing bias (via the MetaNSUE algorithm) and including non-statistically significant unreported effects. SDM-PSI was used to analyze 105 whole-brain GMV voxel-based morphometry (VBM) studies comparing 6,530 individuals with MDD versus 6,821 age-matched healthy controls (HC). A laterality effect was observed in which adults with MDD showed lower GMV than adult HC in left fronto-temporo-parietal structures (superior temporal gyrus, insula, Rolandic operculum, and inferior frontal gyrus). However, these abnormalities were not statistically significant for adolescent MDD versus adolescent HC. Instead, adolescent MDD showed lower GMV than adult MDD in right temporo-parietal structures (angular gyrus and middle temporal gyrus). These regional differences may be used as potential biomarkers to predict and monitor treatment outcomes as well as to choose the most effective treatments in adolescents versus adults. Finally, due to the paucity of youth, older adult, and longitudinal studies, future studies should attempt to replicate these GMV findings and examine whether they correlate with treatment response and illness severity.

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This retrospective cohort study was conducted on 1148 males who presented along with their partners for infertility management at the PIVET Medical Centre between 2013 and 2022 and had a sperm DNA fragmentation (SDF) assay performed by Halosperm, thereafter participating in 1600 assisted reproductive technology (ART) cycles utilising one of three modalities, namely, IVF-Only, ICSI-Only or IVF-ICSI Split cycles. The outcomes from the ART cycles were then analysed as two groups based on SDF levels <15% and ≥15%. The study showed the unadjusted fertilization rates were not different between the groups, neither across the four female age ranges. However, when the fertilization rates were adjusted for the mature oocytes (metaphase-II oocytes), there was a highly significant difference in fertilization rates in favour of the group with SDF levels < 15% where the women were in the younger age grouping of <35 years (78.4% vs. 73.0%; p < 0.0001). Overall, there was no difference in the rates of blastocyst development nor clinical pregnancy rates between the two SDF groups, but there was a significantly higher pregnancy rate for the younger women (<35 years) with the group of SDF level < 15% (44.1% vs. 37.4%; p = 0.04). Similarly, there was no difference in the miscarriage rates overall with respect to SDF groups, and no clear picture could be deciphered among the women's age groups. With respect to cumulative live births, this reflected the pregnancy rates with no overall difference between the two SDF groups, but there was a significantly higher cumulative live birth rate for women <35 years where the SDF level was <15% (38.6% vs. 28.6%; p < 0.01). Among the three modalities, the highest cumulative live birth rate occurred within the group with SDF level < 15%, being highest with the IVF mode, particularly for women aged <40 years (43.0% vs. 37.7% for IVF-ICSI Split and 27.9% for ICSI; p = 0.0002), noting that the IVF case numbers were disproportionately low.

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This study examined age effects in the standardization samples of the Wechsler Memory Scale-Fourth Edition (WMS-IV) and compared these, where appropriate, to the norms of the Wechsler Memory Scale-Third Edition (WMS-III). On the Adult (16-69 years) and Older Adult (65-90 years) batteries of the WMS-IV, the most pronounced declines were on the Visual Memory Indexes starting in the 35-44 years cohort. The Auditory Memory Indexes showed the least deterioration, which did not commence until the 85-90 years age range. Subtest scores for the Adult Battery indicated that Logical Memory I was unchanged from 16 to 69 years. Likewise, only one scaled score point decline was evidenced on Logical Memory II. Conversely, WMS-III Logical Memory I performance showed a one scaled score point decline in the 18-19 years age band and progressed to moderate (i.e., 4 scaled score points) and large (i.e., ≥6 scaled score points) reductions by the 65-69 and ≥80 years cohorts. Logical Memory II showed even greater age-related deterioration. Age decline data at each age cohort are provided for all subtests and indexes from the Adult and Older Adult batteries as well as for the WMS-III subtests in common with the WMS-IV.

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This retrospective cohort study reports on 1291 males who were the partners of women presenting with infertility requiring assisted reproduction and who had sperm DNA fragmentation (SDF) levels measured by the Halosperm test. These men provided clinical and biometric details which included their age, stature, weight, and body mass index (BMI). Of these men, 562 (43.5%) provided detailed historical records of their smoking and alcohol histories. The aim of this study was to determine whether any clinical and biometric parameters, or main lifestyle factors, had any influence on SDF. We found that the only clinical parameter with a direct correlation was that of advancing age (r = 0.064, p = 0.02), but none of the biometric parameters of stature, weight, or BMI showed any significant correlation. In respect to lifestyle, there were significant correlations with smoking history, but not in the way we expected. Our data showed significantly elevated SDF levels among non-smokers (p = 0.03) compared with smokers. We also found that, among the non-smokers, ex-smokers had higher SDF levels (p = 0.03). With respect to alcohol, consumers did not show any significant differences in SDF levels. These lifestyle findings did not show any significant relevance with respect to an SDF level of <15% or ≥15%. Furthermore, logistic regression analysis excluded age as a confounder in these lifestyle findings. It is therefore concluded that, apart from age, both clinical and lifestyle aspects have minimal relevance to SDF.

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In 2005, Science magazine designated the problem of accounting for difficulties in L2 (second language) learning as one of the 125 outstanding challenges facing scientific research. A maturationally-based sensitive period has long been the favorite explanation for why ultimate foreign language attainment declines with age-of-acquisition. However, no genetic or neurobiological mechanisms for limiting language learning have yet been identified. At the same time, we know that cognitive, social, and motivational factors change in complex ways across the human lifespan. Emergentist theory provides a framework for relating these changes to variation in the success of L2 learning. The great variability in patterns of learning, attainment, and loss across ages, social groups, and linguistic levels provides the core motivation for the emergentist approach. Our synthesis incorporates three groups of factors which change systematically with age: environmental supports, cognitive abilities, and motivation for language learning. This extended emergentist account explains why and when second language succeeds for some children and adults and fails for others.

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