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Sample records for early age strength

  1. Early-age concrete strength estimation based on piezoelectric sensor using artificial neural network

    NASA Astrophysics Data System (ADS)

    Kim, Junkyeong; Kim, Ju-Won; Park, Seunghee

    2014-04-01

    Recently, novel methods to estimate the strength of concrete have been reported based on numerous NDT methods. Especially, electro-mechanical impedance technique using piezoelectric sensors are studied to estimate the strength of concrete. However, the previous research works could not provide the general information about the early-age strength important to manage the quality of concrete and/or the construction process. In order to estimate the early-age strength of concrete, the electro-mechanical impedance method and the artificial neural network(ANN) is utilized in this study. The electro-mechanical impedance varies with the mechanical properties of host structures. Because the strength development is most influential factor among the change of mechanical properties at early-age of curing, it is possible to estimate the strength of concrete by analyzing the change of E/M impedance. The strength of concrete is a complex function of several factors like mix proportion, temperature, elasticity, etc. Because of this, it is hard to mathematically derive equations about strength of concrete. The ANN can provide the solution about early-age strength of concrete without mathematical equations. To verify the proposed approach, a series of experimental studies are conducted. The impedance signals are measured using embedded piezoelectric sensors during curing process and the resonant frequency of impedance is extracted as a strength feature. The strength of concrete is calculated by regression of strength development curve obtained by destructive test. Then ANN model is established by trained using experimental results. Finally the ANN model is verified using impedance data of other sensors.

  2. Grip strength is potentially an early indicator of age-related decline in mice

    PubMed Central

    Ge, Xuan; Cho, Anthony; Ciol, Marcia A.; Pettan-Brewer, Christina; Snyder, Jessica; Rabinovitch, Peter; Ladiges, Warren

    2016-01-01

    The hand grip test has been correlated with mobility and physical performance in older people and has been shown to be a long-term predictor of mortality. Implementation of new strategies for enhancing healthy aging and maintaining independent living are dependent on predictable preclinical studies. The mouse is used extensively as a model in these types of studies, and the paw grip strength test is similar to the hand grip test for people in that it assesses the ability to grip a device with the paw, is non-invasive and easy to perform, and provides reproducible information. However, little has been reported on how grip strength declines with increasing age in mice. This report shows that grip strength was decreased in C57BL/6 (B6) NIA and C57BL/6×BALB/c F1 (CB6F1) NIA male mice at 12 months of age compared to 8-month-old mice, and continued a robust decline to 20 months and then 28 months of age, when the study was terminated. The decline was not related to lean muscle mass, but extensive age-related carpal and digital exostosis could help explain the decreased grip strength times with increasing age. In conclusion, the grip strength test could be useful in mouse preclinical studies to help make translational predictions on treatment strategies to enhance healthy aging. PMID:27613499

  3. Grip strength is potentially an early indicator of age-related decline in mice.

    PubMed

    Ge, Xuan; Cho, Anthony; Ciol, Marcia A; Pettan-Brewer, Christina; Snyder, Jessica; Rabinovitch, Peter; Ladiges, Warren

    2016-01-01

    The hand grip test has been correlated with mobility and physical performance in older people and has been shown to be a long-term predictor of mortality. Implementation of new strategies for enhancing healthy aging and maintaining independent living are dependent on predictable preclinical studies. The mouse is used extensively as a model in these types of studies, and the paw grip strength test is similar to the hand grip test for people in that it assesses the ability to grip a device with the paw, is non-invasive and easy to perform, and provides reproducible information. However, little has been reported on how grip strength declines with increasing age in mice. This report shows that grip strength was decreased in C57BL/6 (B6) NIA and C57BL/6×BALB/c F1 (CB6F1) NIA male mice at 12 months of age compared to 8-month-old mice, and continued a robust decline to 20 months and then 28 months of age, when the study was terminated. The decline was not related to lean muscle mass, but extensive age-related carpal and digital exostosis could help explain the decreased grip strength times with increasing age. In conclusion, the grip strength test could be useful in mouse preclinical studies to help make translational predictions on treatment strategies to enhance healthy aging. PMID:27613499

  4. Early age strength enhancement of blended cement systems by CaCl{sub 2} and diethanol-isopropanolamine

    SciTech Connect

    Riding, Kyle; Silva, Denise A.; Scrivener, Karen

    2010-06-15

    The enhancement of the 1 day strength of cementitious systems by a combination of calcium chloride (CaCl{sub 2}) and diethanol-isopropanolamine (DEIPA) was studied, particularly in blended cement systems. A combination of quantitative X-ray diffraction with Rietveld refinement (QXRD), scanning electron microscopy (SEM)/backscattered electron image analysis, thermogravimetric analysis (TGA), and isothermal calorimetry were used to investigate the mechanism of strength enhancement by the additives. The additives were found to increase the early age mortar strength by enhancing the cement hydration, with the DEIPA enhancing primarily the aluminate hydration. DEIPA also affected the morphology of portlandite which was formed as thin plates. In parallel, the calcium-to-silica ratio of the C-S-H was found to increase with the use of DEIPA, possibly because of the inclusion of microcrystalline portlandite. After 48 h DEIPA was found to directly enhance the rate of reaction of granulated blast-furnace slag and fly ash.

  5. Age and grip strength predict hand dexterity in adults.

    PubMed

    Martin, Jason A; Ramsay, Jill; Hughes, Christopher; Peters, Derek M; Edwards, Martin G

    2015-01-01

    In the scientific literature, there is much evidence of a relationship between age and dexterity, where increased age is related to slower, less nimble and less smooth, less coordinated and less controlled performances. While some suggest that the relationship is a direct consequence of reduced muscle strength associated to increased age, there is a lack of research that has systematically investigated the relationships between age, strength and hand dexterity. Therefore, the aim of this study was to examine the associations between age, grip strength and dexterity. 107 adults (range 18-93 years) completed a series of hand dexterity tasks (i.e. steadiness, line tracking, aiming, and tapping) and a test of maximal grip strength. We performed three phases of analyses. Firstly, we evaluated the simple relationships between pairs of variables; replicating the existing literature; and found significant relationships of increased age and reduced strength; increased age and reduced dexterity, and; reduced strength and reduced dexterity. Secondly, we used standard Multiple Regression (MR) models to determine which of the age and strength factors accounted for the greater variance in dexterity. The results showed that both age and strength made significant contributions to the data variance, but that age explained more of the variance in steadiness and line tracking dexterity, whereas strength explained more of the variance in aiming and tapping dexterity. In a third phase of analysis, we used MR analyses to show an interaction between age and strength on steadiness hand dexterity. Simple Slopes post-hoc analyses showed that the interaction was explained by the middle to older aged adults showing a relationship between reduced strength and reduced hand steadiness, whereas younger aged adults showed no relationship between strength and steadiness hand dexterity. The results are discussed in terms of how age and grip strength predict different types of hand dexterity in

  6. A new test method for young age strength of shotcrete

    SciTech Connect

    Teramoto, Shozo

    1995-12-31

    As a method for testing the young-age strength of shotcrete used as tunnel supports, use of the Parotester, which is designed to measure the hardness of paper rolls at printing factories, has been considered. This paper reports the results of laboratory tests conducted to establish this method as a means of strength testing.

  7. [Age, activity and strength of knee ligaments].

    PubMed

    Kasperczyk, W J; Rosocha, S; Bosch, U; Oestern, H J; Tscherne, H

    1991-07-01

    The cruciate ligaments of older persons are thought to have diminished biomechanical properties. On the other hand, joint immobilization also leads to similar functional losses in ligaments. It can be difficult to differentiate between these factors in older and immobile persons. The anterior and posterior cruciate ligaments of six younger (average age 30 years) and six older (average age 64.7 years) donors with similar levels of activity were subjected to biomechanical testing. Each sample had to meet the following conditions: appropriate age, no chronic vascular and cardiopulmonary disease found on autopsy, no signs of osteoarthrosis and no knee injuries. The material properties of maximum stress (e.g. ACL: young/old 24/21N/mm2), elastic modulus (e.g. ACL: young/old 144/129 MPa), and strain (e.g. ACL: young/old 25/28%), did not differ significantly (p less than 0.05). This indicates that older persons who are active do not necessarily show functional losses in the cruciate ligaments. Other data found in the literature can be ascribed to immobilization influences. In this data many of the older test persons had chronic vascular insufficiency, cardiopulmonary disease or malignancies.

  8. Early reduction in toe flexor strength is associated with physical activity in elderly men

    PubMed Central

    Suwa, Masataka; Imoto, Takayuki; Kida, Akira; Yokochi, Takashi

    2016-01-01

    [Purpose] To compare the toe flexor, hand grip and knee extensor strengths of young and elderly men, and to examine the association between toe flexor strength and physical activity or inactivity levels. [Subjects and Methods] Young (n=155, 18–23 years) and elderly (n=60, 65–88 years) men participated in this study. Toe flexor, hand grip, and knee extensor strength were measured. Physical activity (time spent standing/walking per day) and inactivity (time spent sitting per day) were assessed using a self-administered questionnaire. [Results] Toe flexor, hand grip, and knee extensor strength of the elderly men were significantly lower than those of the young men. Standing/walking and sitting times of the elderly men were lower than those of the young men. Toe flexor strength correlated with hand grip and knee extensor strength in both groups. In elderly men, toe flexor strength correlated with standing/walking time. In comparison to the young men’s mean values, toe flexor strength was significantly lower than knee extensor and hand grip strength in the elderly group. [Conclusion] The results suggest that age-related reduction in toe flexor strength is greater than those of hand grip and knee extensor strengths. An early loss of toe flexor strength is likely associated with reduced physical activity in elderly men. PMID:27313353

  9. Early reduction in toe flexor strength is associated with physical activity in elderly men.

    PubMed

    Suwa, Masataka; Imoto, Takayuki; Kida, Akira; Yokochi, Takashi

    2016-05-01

    [Purpose] To compare the toe flexor, hand grip and knee extensor strengths of young and elderly men, and to examine the association between toe flexor strength and physical activity or inactivity levels. [Subjects and Methods] Young (n=155, 18-23 years) and elderly (n=60, 65-88 years) men participated in this study. Toe flexor, hand grip, and knee extensor strength were measured. Physical activity (time spent standing/walking per day) and inactivity (time spent sitting per day) were assessed using a self-administered questionnaire. [Results] Toe flexor, hand grip, and knee extensor strength of the elderly men were significantly lower than those of the young men. Standing/walking and sitting times of the elderly men were lower than those of the young men. Toe flexor strength correlated with hand grip and knee extensor strength in both groups. In elderly men, toe flexor strength correlated with standing/walking time. In comparison to the young men's mean values, toe flexor strength was significantly lower than knee extensor and hand grip strength in the elderly group. [Conclusion] The results suggest that age-related reduction in toe flexor strength is greater than those of hand grip and knee extensor strengths. An early loss of toe flexor strength is likely associated with reduced physical activity in elderly men. PMID:27313353

  10. Successful Aging: Early Influences and Contemporary Characteristics

    ERIC Educational Resources Information Center

    Pruchno, Rachel A.; Wilson-Genderson, Maureen; Rose, Miriam; Cartwright, Francine

    2010-01-01

    Purpose: Positing that successful aging has independent, yet related, dimensions that are both objective and subjective, we examine how early influences and contemporary characteristics define 4 groups of people. Design and Methods: Data were gathered from 5,688 persons aged 50-74 years living in New Jersey who participated in telephone…

  11. Implementing paraprofessional strength-based early intervention home visitations.

    PubMed

    Mykota, David B

    2008-08-01

    The purpose of the present study is to evaluate the implementation process for Parenting Plus, an early intervention program in a rural, western Canadian health district. Parenting Plus, as modeled after Hawaii Healthy Start, provides strength-based paraprofessional home visitations to overburdened parents of newborns. The general inductive approach guided the studies design and the methods used for data collection and analysis. Semi-structured in-depth interviews were conducted with health care practitioners and focus groups with program participants were held until theoretical saturation was achieved for both. Recommendations for policy and practice address the need for intersectoral involvement as crucial to a strength-based pilot project's success. Future research needs not only to look at the mode of service delivery but also, more importantly, at how the characteristics of the home visitor can effect change in the participant and what level of experience or education (paraprofessional or professional) is best suited to a particular client population. PMID:18502507

  12. [Age changes in early somatosensory evoked potentials].

    PubMed

    Strenge, H

    1986-06-01

    There are characteristic age-related changes in the cervical and early cortical somatosensory potentials evoked by electrical stimulation of the median nerve. At an age of 40 to 50 years the latencies of the potential components and the transit times start increasing progressively. Moreover, there is an attenuation of the cervical and an enhancement of the cortical components with age. Considering the presumed neuronal basis of the bioelectric phenomena the changes are discussed in connection with aging processes of the spinal ganglion cells, cortical pyramidal cells and the locus coeruleus. PMID:3017682

  13. Age at spinal cord injury determines muscle strength

    PubMed Central

    Thomas, Christine K.; Grumbles, Robert M.

    2014-01-01

    As individuals with spinal cord injury (SCI) age they report noticeable deficits in muscle strength, endurance and functional capacity when performing everyday tasks. These changes begin at ~45 years. Here we present a cross-sectional analysis of paralyzed thenar muscle and motor unit contractile properties in two datasets obtained from different subjects who sustained a cervical SCI at different ages (≤46 years) in relation to data from uninjured age-matched individuals. First, completely paralyzed thenar muscles were weaker when C6 SCI occurred at an older age. Muscles were also significantly weaker if the injury was closer to the thenar motor pools (C6 vs. C4). More muscles were strong (>50% uninjured) in those injured at a younger (≤25 years) vs. young age (>25 years), irrespective of SCI level. There was a reduction in motor unit numbers in all muscles tested. In each C6 SCI, only ~30 units survived vs. 144 units in uninjured subjects. Since intact axons only sprout 4–6 fold, the limits for muscle reinnervation have largely been met in these young individuals. Thus, any further reduction in motor unit numbers with time after these injuries will likely result in chronic denervation, and may explain the late-onset muscle weakness routinely described by people with SCI. In a second dataset, paralyzed thenar motor units were more fatigable than uninjured units. This gap widened with age and will reduce functional reserve. Force declines were not due to electromyographic decrements in either group so the site of failure was beyond excitation of the muscle membrane. Together, these results suggest that age at SCI is an important determinant of long-term muscle strength, and fatigability, both of which influence functional capacity. PMID:24478643

  14. Mobile Learning and Early Age Mathematics

    ERIC Educational Resources Information Center

    Peled, Shir; Schocken, Shimon

    2014-01-01

    The ability to develop engaging simulations and constructive learning experiences using mobile devices is unprecedented, presenting a disruption in educational practices of historical proportions. In this paper we describe some of the unique virtues that mobile learning hold for early age mathematics education. In particular, we describe how…

  15. Gratitude From Early Adulthood to Old Age.

    PubMed

    Allemand, Mathias; Hill, Patrick L

    2016-02-01

    Are there age differences in gratitude from early adulthood to old age? The current studies tested several ways by which an association between age and dispositional gratitude may present, by considering multiple measures on both fronts. We used data from three cross-sectional studies (total N = 1,736; total age range: 19-94). The results indicated that (a) age effects in gratitude are more likely to occur for subjective age in terms of future time perspective (i.e., people's perceptions of their remaining opportunities and time) than chronological age; (b) chronological age effects are more domain specific than general in nature; and (c) they are more likely to occur for the instrumental domain as compared to the interpersonal domain. Finally, the results indicated that (d) perceived future time, particularly with respect to remaining opportunities, mediates the relation between chronological age and general gratitude. Overall, the findings suggest that gratitude is subject to a variety of developmental influences across adulthood.

  16. Growth in early life predicts bone strength in late adulthood: the Hertfordshire Cohort Study.

    PubMed

    Oliver, Helen; Jameson, Karen A; Sayer, Avan Aihie; Cooper, Cyrus; Dennison, Elaine M

    2007-09-01

    Infant growth is a determinant of adult bone mass, and poor childhood growth is a risk factor for adult hip fracture. Peripheral quantitative computed tomography (pQCT) allows non-invasive assessment of bone strength. We utilised this technology to examine relationships between growth in early life and bone strength. We studied 313 men and 318 women born in Hertfordshire between 1931 and 1939 who were still resident there in adult life, for whom detailed early life records were available. Lifestyle factors were evaluated by questionnaire, anthropometric measurements made, and peripheral QCT examination of the radius and tibia performed (Stratec 4500). Birthweight and conditional weight at 1 year were strongly related to radial and tibial length in both sexes (p<0.001) and to measures of bone strength [fracture load X, fracture load Y, polar strength strain index (SSI)] at both the radius and tibia. These relationships were robust to adjustment for age, body mass index (BMI), social class, cigarette and alcohol consumption, physical activity, dietary calcium intake, HRT use, and menopausal status in women. Among men, BMI was strongly positively associated with radial (r=0.46, p=0.001) and tibial (r=0.24, p=0.006) trabecular bone mineral density (BMD). Current smoking was associated with lower cortical (radius: p=0.0002; tibia: p=0.08) and trabecular BMD (radius: p=0.08; tibia: p=0.04) in males. Similar trends of BMD with these anthropometric and lifestyle variables were seen in women but they were non-significant. Current HRT use was associated with greater female cortical (radius: p=0.0002; tibia: p=0.001) and trabecular (radius: p=0.008; tibia: p=0.04) BMD. Current HRT use was also associated with greater radial strength (polar SSI: p=0.006; fracture load X: p=0.005; fracture load Y: p=0.02) in women. Women who had sustained any fracture since the age of 45 years had lower radial total (p=0.0001), cortical (p<0.005) and trabecular (p=0.0002) BMD, poorer forearm

  17. Age-Related Loss of Muscle Mass and Strength

    PubMed Central

    Goldspink, Geoffrey

    2012-01-01

    Age-related muscle wasting and increased frailty are major socioeconomic as well as medical problems. In the quest to extend quality of life it is important to increase the strength of elderly people sufficiently so they can carry out everyday tasks and to prevent them falling and breaking bones that are brittle due to osteoporosis. Muscles generate the mechanical strain that contributes to the maintenance of other musculoskeletal tissues, and a vicious circle is established as muscle loss results in bone loss and weakening of tendons. Molecular and proteomic approaches now provide strategies for preventing age-related muscle wasting. Here, attention is paid to the role of the GH/IGF-1 axis and the special role of the IGFI-Ec (mechano growth factor/MGF) which is derived from the IGF-I gene by alternative splicing. During aging MGF levels decline but when administered MGF activates the muscle satellite (stem) cells that “kick start” local muscle repair and induces hypertrophy. PMID:22506111

  18. Martensitic transformations in high-strength steels at aging

    NASA Astrophysics Data System (ADS)

    Berezovskaya, V. V.; Bannykh, O. A.

    2011-04-01

    The effect of heat treatment and elastic stresses on the texture of maraging NiTi-steels is studied. The interruption of the decomposition of martensite at the early stages is shown to be accompanied by the γ → α transformation, which proceeds upon cooling from the aging temperature and under elastic (σ < σ0.2) tensile stresses. The martensite has a crystallographic texture, which is caused by the evolution of hot-deformation texture as a result of quenching and decomposition of a supersaturated α solid solution.

  19. Monitoring early age cementitious materials using ultrasonic guided waves

    NASA Astrophysics Data System (ADS)

    Borgerson, Jacob L.

    The evaluation of early age concrete is critical for reducing construction times and ensuring quality. In this study, the use of ultrasonic guided waves for monitoring the development of early age cementitious materials is investigated. A torsional wave is transmitted and received through a waveguide that is embedded in early age mortar or concrete. As the cementitious material sets and hardens, the received wave(s) change, indicating the transition from a semifluid to a solid state. This thesis proposes two systems. The first system is a through-transmission system; a wave is transmitted on one end of an embedded waveguide using a sensor arrangement and then it is received on the opposite end of the rod with another sensor. This approach monitors the attenuation of the fundamental torsional wave mode, resulting from the leakage of energy from the cylindrical steel rod to the surrounding cementitious material. The evolution of the material's properties is related to the energy leakage or attenuation of the guided wave. The second system is a pulse-echo system; a wave is transmitted on one end of a partially embedded waveguide via a sensor arrangement that also receives the reflected signals. This approach monitors both the reflection from the end of the rod and the reflection from the point where the waveguide enters the material. The development of the cementitious material's mechanical properties is related to both the energy leaked into the surrounding material and the energy reflected at the point of entry. The ability of this method to only require access to one side of the specimen makes it attractive for monitoring early age cementitious materials in the field. Experiments were performed on mixtures with varying water-cement ratios (w/c = 0.40, 0.50, and 0.60), chemical admixtures (accelerant and retardant), mineral admixtures (silica fume and fly ash), and coarse aggregate (pea gravel). The time of setting and compressive strength of the various mixtures

  20. Comparison of maximal tongue strength and tongue strength used during swallowing in relation to age in healthy adults

    PubMed Central

    Park, Ji-Su; Oh, Dong-Hwan; Chang, Moonyoung

    2016-01-01

    [Purpose] The aim of this study was to measure and compare the maximal tongue strength and tongue strength used during swallowing in young and older adults. [Subjects and Methods] The study recruited 80 healthy young (aged 20 to 39 years) and older adults (aged ≥65 years) in public places. The Iowa Oral Performance Instrument was used to measure maximal tongue strength and tongue strength used during swallowing. For each subject, the peak value of three measurements was recorded and analyzed. [Results] Maximal tongue strength was statistically significantly higher for the young adults group than the older adults group. Conversely, tongue strength used during swallowing was statistically significantly higher for the older adults group than the young adults group. The percentages of tongue strength used during swallowing for the young adults and older adults groups were approximately 38.8% and 53.8%, respectively. [Conclusion] This study confirmed that older adults have a lower maximal tongue strength than young adults, but a higher tongue strength used during swallowing. PMID:27064477

  1. Early phase changes by concurrent endurance and strength training.

    PubMed

    Balabinis, Christos P; Psarakis, Charalampos H; Moukas, Markos; Vassiliou, Miltos P; Behrakis, Panagiotis K

    2003-05-01

    To compare regimens of concurrent strength and endurance training, 26 male basketball players were matched for stature, body composition, and physical activity level. Subjects completed different training programs for 7 weeks, 4 days per week. Groups were as follows: (a) the strength group (S; n = 7) did strength training; (b) the endurance group (E; n = 7) did endurance training; (c) the strength and endurance group (S + E; n = 7) combined strength and endurance training; and (d) the control group (C; n = 5) had no training. The S + E group showed greater gains in Vo(2)max than the E group did (12.9% vs. 6.8%), whereas the S group showed a decline (8.8%). Gains were noted in strength and vertical jump performance for the S + E and S groups. The S + E group had better posttraining anaerobic power than the S group did (6.2% vs. 2.9%). No strength, power, or anaerobic power gains were present for the E and C groups. We conclude that concurrent endurance and strength training is more effective in terms of improving athletic performance than are endurance and strength training apart.

  2. Age-Related and Sex-Related Differences in Hand and Pinch Grip Strength in Adults

    ERIC Educational Resources Information Center

    Puh, Urska

    2010-01-01

    The purpose of the study was to quantify age-related changes in hand grip strength and three types of pinch grip strength (key pinch, tip pinch, and palmar pinch) among male and female participants. The study included 199 healthy participants (100 females, 99 males) aged 20-79 years, who were divided into four age groups. The Baseline Hydraulic…

  3. Normative data for hand grip strength and key pinch strength, stratified by age and gender for a multiethnic Asian population

    PubMed Central

    Lam, Ngee Wei; Goh, Hui Ting; Kamaruzzaman, Shahrul Bahyah; Chin, Ai-Vyrn; Poi, Philip Jun Hua; Tan, Maw Pin

    2016-01-01

    INTRODUCTION Hand strength is a good indicator of physical fitness and frailty among the elderly. However, there are no published hand strength references for Malaysians aged > 65 years. This study aimed to establish normative data for hand grip strength (HGS) and key pinch strength (KPS) for Malaysians aged ≥ 60 years, and explore the relationship between hand strength and physical ability. METHODS Healthy participants aged ≥ 60 years with no neurological conditions were recruited from rural and urban locations in Malaysia. HGS and KPS were measured using hand grip and key pinch dynamometers. Basic demographic data, anthropometric measures, modified Barthel Index scores and results of the Functional Reach Test (FRT), Timed Up and Go (TUG) test and Jebsen-Taylor Hand Function Test (JTHFT) were recorded. RESULTS 362 subjects aged 60–93 years were recruited. The men were significantly stronger than the women in both HGS and KPS (p < 0.001). The hand strength of the study cohort was lower than that of elderly Western populations. Significant correlations were observed between hand strength, and residential area (p < 0.001), FRT (r = 0.236, p = 0.028), TUG (r = −0.227, p = 0.009) and JTHFT (r = −0.927, p < 0.001). CONCLUSION This study established reference ranges for the HGS and KPS of rural and urban elderly Malaysian subpopulations. These will aid the use of hand strength as a screening tool for frailty among elderly persons in Malaysia. Future studies are required to determine the modifiable factors for poor hand strength. PMID:26768064

  4. Age-related differences in the neck strength of adolescent rugby players

    PubMed Central

    Hamilton, D. F.; Gatherer, D.; Jenkins, P. J.; Maclean, J. G. B.; Hutchison, J. D.; Nutton, R. W.; Simpson, A. H. R. W.

    2012-01-01

    Objectives To evaluate the neck strength of school-aged rugby players, and to define the relationship with proxy physical measures with a view to predicting neck strength. Methods Cross-sectional cohort study involving 382 rugby playing schoolchildren at three Scottish schools (all male, aged between 12 and 18 years). Outcome measures included maximal isometric neck extension, weight, height, grip strength, cervical range of movement and neck circumference. Results Mean neck extension strength increased with age (p = 0.001), although a wide inter-age range variation was evident, with the result that some of the oldest children presented with the same neck strength as the mean of the youngest group. Grip strength explained the most variation in neck strength (R2 = 0.53), while cervical range of movement and neck girth demonstrated no relationship. Multivariable analysis demonstrated the independent effects of age, weight and grip strength, and the resultant model explained 62.1% of the variance in neck strength. This model predicted actual neck strength well for the majority of players, although there was a tendency towards overestimation at the lowest range and underestimation at the highest. Conclusion A wide variation was evident in neck strength across the range of the schoolchild-playing population, with a surprisingly large number of senior players demonstrating the same mean strength as the 12-year-old mean value. This may suggest that current training regimes address limb strength but not neck strength, which may be significant for future neck injury prevention strategies. Age, weight and grip strength can predict around two thirds of the variation in neck strength, however specific assessment is required if precise data is sought. PMID:23610685

  5. Building on People's Strengths: Early Childhood in Africa.

    ERIC Educational Resources Information Center

    Cohen, Ruth; And Others

    This report describes early childhood development (ECD) in Africa and the Bernard van Leer Foundation's strategies for early childhood programs in African nations. Chapter 1 examines the context in which Africa's children are growing up, focusing on the hardships that many children face, as well as the efforts made by families, communities, and…

  6. Using Strengths-Based Approaches in Early Years Practice and Research

    ERIC Educational Resources Information Center

    Fenton, Angela; Walsh, Kerryann; Wong, Sandie; Cumming, Tamara

    2015-01-01

    Strengths-based approaches draw upon frameworks and perspectives from social work and psychology but have not necessarily been consistently defined or well articulated across disciplines. Internationally, there are increasing calls for professionals in early years settings to work in strengths-based ways to support the access and participation of…

  7. Experiential Aging Activities and the Early Adolescent.

    ERIC Educational Resources Information Center

    Glover, Elbert D.; And Others

    1981-01-01

    Negative views about the elderly held by adolescents can result in a negative outlook on aging. Physical, mental, and social aging experiential activities are given which can be done at home or at school. (JN)

  8. Sex-Related and Age-Related Differences in Knee Strength of Basketball Players Ages 11-17 Years.

    PubMed

    Buchanan, Patricia A.; Vardaxis, Vassilios G.

    2003-09-01

    OBJECTIVE: To assess hamstrings and quadriceps strength of basketball players ages 11-13 and 15-17 years. DESIGN AND SETTING: This cross-sectional study occurred during the 2000 American Youth Basketball Tour National Tournament. We investigated whether sex- or age-related strength differences existed among study participants. SUBJECTS: Forty-one tournament participants (22 girls, 19 boys; 11-13 or 15-17 years old) who reported no history of knee sprain or surgery were recruited. MEASUREMENTS: We used a Cybex II dynamometer to obtain isokinetic concentric peak torques relative to body mass (Nm/kg) at 60 degrees /s for hamstrings and quadriceps bilaterally. From average peak torques, we determined ipsilateral hamstrings:quadriceps and homologous muscle-group ratios. RESULTS: Correlations between hamstrings and quadriceps strength measures ranged from 0.78 to 0.97. Players 15-17 years old had greater relative hamstrings and quadriceps strength than 11- to 13-year-old athletes. Age and sex interacted significantly for quadriceps strength. The quadriceps strength of 15- to 17-year-old girls did not differ from that of 11- to 13-year-old girls, whereas 15- to 17-year-old boys had stronger quadriceps than 11- to 13-year-old boys. Boys 15-17 years old had greater quadriceps strength than girls 15-17 years old. CONCLUSIONS: This study is unique in providing normative data for the hamstrings and quadriceps strength of basketball players 11-13 and 15-17 years old. Age-related strength differences did not occur consistently between the sexes, as girls 11-13 and 15-17 years old had similar relative quadriceps strength.

  9. Early Literacy Promotion in the Digital Age.

    PubMed

    Navsaria, Dipesh; Sanders, Lee M

    2015-10-01

    School readiness and educational success is strongly mediated by early literacy skills. In both exam-room and community-based settings, child-health providers can affect the trajectory of early literacy by implementing evidence-based, culturally appropriate interventions that support child development, parenting skills, and child-caregiver interaction. Despite limited research on the subject, these interventions should also attend to the evolving role of digital-media exposure (both positive and negative) on the developmental health of children.

  10. Age at Menarche Is Associated with Divergent Alcohol Use Patterns in Early Adolescence and Early Adulthood

    ERIC Educational Resources Information Center

    Richards, Meghan A.; Oinonen, Kirsten A.

    2011-01-01

    A cross-sectional retrospective design was employed to examine the relationship between age at menarche (AAM) and alcohol use patterns from middle childhood (age 7) to early adulthood in 265 University-aged women. Earlier menarche was associated with: (a) earlier ages at first drink and first intoxication, (b) greater use between ages 9 and 14…

  11. Strength-Based Factors for Successful Adaptation to an Early College High School Environment

    ERIC Educational Resources Information Center

    Abernethy, Catherine

    2010-01-01

    In an early college high school setting, students are subject to varying academic, social and contextual demands of a higher educational environment. In a strength-based study of 136 diverse early college high school students, this research explored the relationship of internal and external developmental assets to adaptive functioning of…

  12. Evaluation of the bond strength between aged composite cores and luting agent

    PubMed Central

    2015-01-01

    PURPOSE The aim of this study was to evaluate effect of different surface treatment methods on the bond strength between aged composite-resin core and luting agent. MATERIALS AND METHODS Seventy-five resin composites and also seventy-five zirconia ceramic discs were prepared. 60 composite samples were exposed to thermal aging (10,000 cycles, 5 to 55℃) and different surface treatment. All specimens were separated into 5 groups (n=15): 1) Intact specimens 2) Thermal aging-air polishing 3) Thermal aging- Er:YAG laser irradiation 4) Thermal aging- acid etching 5) Thermal-aging. All specimens were bonded to the zirconia discs with resin cement and fixed to universal testing machine and bond strength testing loaded to failure with a crosshead speed of 0.5 mm/min. The fractured surface was classified as adhesive failure, cohesive failure and adhesive-cohesive failure. The bond strength data was statistically compared by the Kruskal-Wallis method complemented by the Bonferroni correction Mann-Whitney U test. The probability level for statistical significance was set at α=.05. RESULTS Thermal aging and different surface treatment methods have significant effect on the bond strength between composite-resin cores and luting-agent (P<.05). The mean baseline bond strength values ranged between 7.07 ± 2.11 and 26.05 ± 6.53 N. The highest bond strength of 26.05 ± 6.53 N was obtained with Group 3. Group 5 showed the lowest value of bond strength. CONCLUSION Appropriate surface treatment method should be applied to aged composite resin cores or aged-composites restorations should be replaced for the optimal bond strength and the clinical success. PMID:25932308

  13. YIELD STRENGTH PREDICTION FOR RAPID AGE-HARDENING HEAT TREATMENT OF ALUMINUM ALLOYS

    SciTech Connect

    Yin, Hebi; Sabau, Adrian S; Ludtka, Gerard Michael; Skszek, Timothy; Niu, X

    2013-01-01

    A constitutive model has been developed to predict the yield strength aging curves for aluminum casting alloys during non-isothermal age-hardening processes. The model provides the specific relationship between the process variables and yield strength. Several aging heat treatment scenarios have been investigated using the proposed model, including two-step aging recipes. Two-step aging heat treatments involve a low temperature regime to promote nucleation of secondary phases and a second step at higher temperature for the growth of the secondary phases. The predicted results show that yield strength of approximately 300MPa might be obtained in shorter aging time, of approximately 30 minutes. Thus, better mechanical properties can be obtained by optimizing the time-temperature schedules for the precipitation hardening process of heat treatable aluminum alloys.

  14. Longitudinal analysis in Plantago: strength of selection and reverse-age analysis reveal age-indeterminate senescence

    PubMed Central

    Shefferson, Richard P.; Roach, Deborah A.

    2013-01-01

    Summary 1. Senescence is usually viewed as increased age-specific mortality or decreased age-specific fecundity due to the declining ability of natural selection to remove deleterious age-specific mutations with age. In herbaceous perennial plants, trends in age-specific mortality are often confounded by size. Age-indeterminate senescence, where accumulated physiological damage varies strongly with environment, may be a better model of senescence in these species. 2. We analysed trends in size and fertility in Plantago lanceolata, using a long-term demographic census involving >10 years and >8,000 individuals in 4 cohorts. We used elasticity and pairwise invasion analysis of life history function-parameterized age × stage matrices to assess whether the force of natural selection declined with age. Then, we used reverse age analysis of size and fertility to assess whether age-indeterminate senescence occurred. Reverse age analysis uses longitudinal data for individuals that have died to look at trait patterns as a function of both age and remaining time to death. We hypothesized that i) the strength of natural selection would decline strongly with age, and ii) physiological condition would deteriorate for several years prior to death. 3. Both elasticity and invasion analyses suggested that the strength of natural selection through mortality declined strongly with age once size was accounted for. Further, reverse age analyses showed that individuals shrank for ~3yrs prior to death, suggesting physiological decline. Inflorescence production declined with age, and also declined in the 3 years prior to death regardless of overall age. 4. Synthesis The hypothesis that plants escape senescence generally assumes that plants can continue to grow larger and increase reproduction as they get older. The results here show that size and reproduction decline with age and the rates of these declines toward death are lifespan- and age-dependent. Further research is needed to

  15. Early Literacy Promotion in the Digital Age.

    PubMed

    Navsaria, Dipesh; Sanders, Lee M

    2015-10-01

    School readiness and educational success is strongly mediated by early literacy skills. In both exam-room and community-based settings, child-health providers can affect the trajectory of early literacy by implementing evidence-based, culturally appropriate interventions that support child development, parenting skills, and child-caregiver interaction. Despite limited research on the subject, these interventions should also attend to the evolving role of digital-media exposure (both positive and negative) on the developmental health of children. PMID:26318952

  16. Growth curve analyses of the relationship between early maternal age and children's mathematics and reading performance.

    PubMed

    Torres, D Diego

    2015-03-01

    Regarding the methods used to examine the early maternal age-child academic outcomes relationship, the extant literature has tended to examine change using statistical analyses that fail to appreciate that individuals vary in their rates of growth. Of the one study I have been able to find that employs a true growth model to estimate this relationship, the authors only controlled for characteristics of the maternal household after family formation; confounding background factors of mothers that might select them into early childbearing, a possible source of bias, were ignored. The authors' findings nonetheless suggested an inverse relationship between early maternal age, i.e., a first birth between the ages of 13 and 17, and Canadian adolescents' mean math performance at age 10. Early maternal age was not related to the linear slope of age. To elucidate whether the early maternal age-child academic outcomes association, treated in a growth context, is consistent with this finding, the present study built on it using US data and explored children's mathematics and reading trajectories from age 5 on. Its unique contribution is that it further explicitly controlled for maternal background factors and employed a three-level growth model with repeated measures of children nested within their mothers. Though the strength of the relationship varied between mean initial academic performance and mean academic growth, results confirmed that early maternal age was negatively related to children's mathematics and reading achievement, net of post-teen first birth child-specific and maternal household factors. Once maternal background factors were included, there was no statistically significant relationship between early maternal age and either children's mean initial mathematics and reading scores or their mean mathematics and reading growth.

  17. Internationally Adopted Children in the Early School Years: Relative Strengths and Weaknesses in Language Abilities

    ERIC Educational Resources Information Center

    Glennen, Sharon

    2015-01-01

    Purpose: This study aimed to determine the relative strengths and weaknesses in language and verbal short-term memory abilities of school-age children who were adopted from Eastern Europe. Method: Children adopted between 1;0 and 4;11 (years;months) of age were assessed with the Clinical Evaluation of Language Fundamentals-Preschool, Second…

  18. Early Microbial Evolution: The Age of Anaerobes.

    PubMed

    Martin, William F; Sousa, Filipa L

    2016-02-01

    In this article, the term "early microbial evolution" refers to the phase of biological history from the emergence of life to the diversification of the first microbial lineages. In the modern era (since we knew about archaea), three debates have emerged on the subject that deserve discussion: (1) thermophilic origins versus mesophilic origins, (2) autotrophic origins versus heterotrophic origins, and (3) how do eukaryotes figure into early evolution. Here, we revisit those debates from the standpoint of newer data. We also consider the perhaps more pressing issue that molecular phylogenies need to recover anaerobic lineages at the base of prokaryotic trees, because O2 is a product of biological evolution; hence, the first microbes had to be anaerobes. If molecular phylogenies do not recover anaerobes basal, something is wrong. Among the anaerobes, hydrogen-dependent autotrophs--acetogens and methanogens--look like good candidates for the ancestral state of physiology in the bacteria and archaea, respectively. New trees tend to indicate that eukaryote cytosolic ribosomes branch within their archaeal homologs, not as sisters to them and, furthermore tend to root archaea within the methanogens. These are major changes in the tree of life, and open up new avenues of thought. Geochemical methane synthesis occurs as a spontaneous, abiotic exergonic reaction at hydrothermal vents. The overall similarity between that reaction and biological methanogenesis fits well with the concept of a methanogenic root for archaea and an autotrophic origin of microbial physiology. PMID:26684184

  19. Effect of nutritional interventions and resistance exercise on aging muscle mass and strength.

    PubMed

    Candow, Darren G; Forbes, Scott C; Little, Jonathan P; Cornish, Stephen M; Pinkoski, Craig; Chilibeck, Philip D

    2012-08-01

    Sarcopenia, defined as the age-related loss of muscle mass, has a negative effect on strength, functional independence and overall quality of life. Sarcopenia is a multifactorial phenomenon characterized by changes in muscle morphology, protein and hormonal kinetics, oxidative stress, inflammation, physical activity and nutrition. It is well known that resistance exercise increases aging muscle mass and strength and these physiological adaptations from exercise may be further enhanced with certain nutritional interventions. Research indicates that essential amino acids and milk-based proteins, creatine monohydrate, essential fatty acids, and vitamin D may all have beneficial effects on aging muscle biology. PMID:22684187

  20. Early-age volume changes of extrudable reactive powder concrete

    NASA Astrophysics Data System (ADS)

    Cherkaoui, K.; Courtial, M.; Dunstetter, F.; Khelidj, A.; Mounanga, P.; de Noirfontaine, M. N.

    2010-06-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  1. Motor Competence in Early Childhood Is Positively Associated With Bone Strength in Late Adolescence

    PubMed Central

    Sayers, Adrian; Deere, Kevin C; Emond, Alan; Tobias, Jon H

    2016-01-01

    ABSTRACT The onset of walking in early childhood results in exposure of the lower limb to substantial forces from weight bearing activity that ultimately contribute to adult bone strength. Relationships between gross motor score (GMS), at 18 months and bone outcomes measured at age 17 years were examined in 2327 participants in the Avon Longitudinal Study of Parents and Children (ALSPAC). Higher GMS indicated greater motor competence in weight‐bearing activities. Total hip bone mineral density (BMD) and hip cross‐sectional moment of inertia (CSMI) were assessed from dual‐energy X‐ray absorptiometry (DXA). Bone measures including cortical bone mineral content (BMC), periosteal circumference (PC), cortical thickness (CT), cortical bone area (CBA), cortical BMD (BMDC) and cross‐sectional moment of inertia (CSMI) were assessed by peripheral quantitative computed tomography (pQCT) at 50% distal‐proximal length. Before adjustment, GMS was associated with hip BMD, CSMI, and tibia BMC, PC, CT, CBA and CSMI (all p < 0.001) but not BMDC (p > 0.25). Strongest associations (standardized regression coefficients with 95% CI) were between GMS and hip BMD (0.086; 95% CI, 0.067 to 0.105) and tibia BMC (0.105; 95% CI, 0.089 to 0.121). With the exception of hip BMD, larger regression coefficients were observed in males (gender interactions all p < 0.05). Adjustment for lean mass resulted in substantial attenuation of regression coefficients, suggesting associations between impaired motor competence and subsequent bone development are partly mediated by alterations in body composition. In conclusion, impaired motor competence in childhood is associated with lower adolescent bone strength, and may represent a risk factor for subsequent osteoporosis. © 2015 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR). PMID:26713753

  2. Early Parenthood and Coming of Age in the 1990s.

    ERIC Educational Resources Information Center

    Rosenheim, Margaret K., Ed.; Testa, Mark F., Ed.

    This book examines how early parenthood differs historically, cross-nationally (in Korea and Sweden), and by class, race, and age in the United States. Contributors discuss how consequential is early parenthood for the future social and economic well-being of parents and children, whether postponing childbearing beyond the teenage years would…

  3. Boosting Early Development: The Mixed Effects of Kindergarten Enrollment Age

    ERIC Educational Resources Information Center

    Zhang, Jiahui; Xin, Tao

    2012-01-01

    This study aimed to investigate the effects of kindergarten enrollment age on four-year-old Chinese children's early cognition and problem behavior using multilevel models. The sample comprised of 1,391 pre-school children (the mean age is 4.58 years old) from 74 kindergartens in six different provinces. The results demonstrated curvilinear…

  4. The Association of Kindergarten Entry Age with Early Literacy Outcomes

    ERIC Educational Resources Information Center

    Huang, Francis L.; Invernizzi, Marcia A.

    2012-01-01

    The authors investigated whether age at kindergarten entry was associated with early literacy achievement gaps and if these gaps persisted over time. Using the kindergarten age eligibility cutoff date, they created 2 groups of students who represented the oldest and youngest children in a cohort of students in high-poverty, low-performing schools.…

  5. Early Middle Ear Effusion and Language at Age Seven

    ERIC Educational Resources Information Center

    Johnson, Dale L.; McCormick, David P.; Baldwin, Constance D.

    2008-01-01

    This study examined the relation of middle ear effusion (MEE) in the first 3 years of life to language outcomes at age seven. It was hypothesized, on the basis of a literature review, that (1) a low, but positive relation between early MEE and language measures in general will be observed at age seven, and (2) major effects will be demonstrated…

  6. Insulin Resistance Is Associated With Decreased Quadriceps Muscle Strength in Nondiabetic Adults Aged ≥70 Years

    PubMed Central

    Barzilay, Joshua I.; Cotsonis, George A.; Walston, Jeremy; Schwartz, Ann V.; Satterfield, Suzanne; Miljkovic, Iva; Harris, Tamara B.

    2009-01-01

    OBJECTIVE Lower-limb muscle strength is reduced in many people with diabetes. In this study, we examined whether quadriceps muscle strength is reduced in relation to insulin resistance in well-functioning ambulatory nondiabetic individuals. RESEARCH DESIGN AND METHODS Participants (age ≥70 years) underwent dual-energy X-ray absorptiometry (DEXA) scanning to ascertain muscle and fat mass, tests of quadriceps strength, computed tomography scanning of the quadriceps to gauge muscle lipid content, and fasting insulin and glucose level measurements from which homeostasis model assessment of insulin resistance (HOMA-IR) was derived. RESULTS In regression analysis, quadriceps strength per kilogram of muscle mass was negatively associated (P < 0.0001) with HOMA-IR independent of other factors negatively associated with strength such as increased age, female sex, low-physical activity, impaired fasting glucose, and increased total body fat. Muscle lipid content was not associated with strength. CONCLUSIONS A small decrease in quadriceps muscle force is associated with increased HOMA-IR in well-functioning nondiabetic adults, suggesting that diminished quadriceps muscle strength begins before diabetes. PMID:19171728

  7. Fracture Strength of Aged Monolithic and Bilayer Zirconia-Based Crowns.

    PubMed

    Lameira, Deborah Pacheco; Buarque e Silva, Wilkens Aurélio; Andrade e Silva, Frederico; De Souza, Grace M

    2015-01-01

    The purpose of this study was to evaluate the effect of design and surface finishing on fracture strength of yttria-tetragonal zirconia polycrystal (Y-TZP) crowns in monolithic (1.5 mm thickness) and bilayer (0.8 mm zirconia coping and 0.7 mm porcelain veneer) configuration after artificial aging. Bovine incisors received crown preparation and Y-TZP crowns were manufactured using CAD/CAM technique, according to the following groups (n = 10): Polished monolithic zirconia crowns (PM); Glazed monolithic zirconia crowns (GM); Bi-layer crowns (BL). Crowns were cemented with resin cement, submitted to artificial aging in a chewing simulator (2.5 million cycles/80 N/artificial saliva/37 °C), and tested for fracture strength. Two remaining crowns referring to PM and GM groups were submitted to a chemical composition analysis to measure the level of yttrium after aging. One-way ANOVA and Tukey's test (P = .05) indicated that monolithic zirconia crowns presented similar fracture strength (PM = 3476.2 N ± 791.7; GM = 3561.5 N ± 991.6), which was higher than bilayer crowns (2060.4 N ± 810.6). There was no difference in the yttrium content among the three surfaces evaluated in the monolithic crowns. Thus, monolithic zirconia crowns present higher fracture strength than bilayer veneered zirconia after artificial aging and surface finishing does not affect their fracture strength. PMID:26576423

  8. Lower Limb Strength in Professional Soccer Players: Profile, Asymmetry, and Training Age

    PubMed Central

    Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George

    2010-01-01

    Kicking and cutting skills in soccer are clearly unilateral, require asymmetrical motor patterns and lead to the development of asymmetrical adaptations in the musculoskeletal function of the lower limbs. Assuming that these adaptations constitute a chronicity-dependent process, this study examined the effects of professional training age (PTA) on the composite strength profile of the knee and ankle joint in soccer players. One hundred soccer players (n=100) with short (5-7 years), intermediate (8-10 years) and long (>11 years) PTA were tested bilaterally for isokinetic concentric and eccentric strength of the knee and ankle muscles. Knee flexion-extension was tested concentrically at 60°, 180° and 300 °/sec and eccentrically at 60° and 180 °/sec. Ankle dorsal and plantar flexions were tested at 60 °/sec for both the concentric and eccentric mode of action. Bilaterally averaged muscle strength [(R+L)/2] increased significantly from short training age to intermediate and stabilized afterwards. These strength adaptations were mainly observed at the concentric function of knee extensors at 60°/sec (p = 0. 023), knee flexors at 60°/sec (p = 0.042) and 180°/sec (p = 0.036), and ankle plantar flexors at 60o/sec (p = 0.044). A linear trend of increase in isokinetic strength with PTA level was observed for the eccentric strength of knee flexors at 60°/sec (p = 0.02) and 180°/sec (p = 0.03). Directional (R/L) asymmetries decreased with PTA, with this being mainly expressed in the concentric function of knee flexors at 180°/sec (p = 0.04) and at 300 °/sec (p = 0.03). These findings confirm the hypothesis of asymmetry in the strength adaptations that take place at the knee and ankle joint of soccer players mainly along with short and intermediate PTA. Players with a longer PTA seem to adopt a more balanced use of their lower extremities to cope with previously developed musculoskeletal asymmetries and possibly reduce injury risk. This has certain implications

  9. Lower limb strength in professional soccer players: profile, asymmetry, and training age.

    PubMed

    Fousekis, Konstantinos; Tsepis, Elias; Vagenas, George

    2010-01-01

    Kicking and cutting skills in soccer are clearly unilateral, require asymmetrical motor patterns and lead to the development of asymmetrical adaptations in the musculoskeletal function of the lower limbs. Assuming that these adaptations constitute a chronicity-dependent process, this study examined the effects of professional training age (PTA) on the composite strength profile of the knee and ankle joint in soccer players. One hundred soccer players (n=100) with short (5-7 years), intermediate (8-10 years) and long (>11 years) PTA were tested bilaterally for isokinetic concentric and eccentric strength of the knee and ankle muscles. Knee flexion-extension was tested concentrically at 60°, 180° and 300 °/sec and eccentrically at 60° and 180 °/sec. Ankle dorsal and plantar flexions were tested at 60 °/sec for both the concentric and eccentric mode of action. Bilaterally averaged muscle strength [(R+L)/2] increased significantly from short training age to intermediate and stabilized afterwards. These strength adaptations were mainly observed at the concentric function of knee extensors at 60°/sec (p = 0. 023), knee flexors at 60°/sec (p = 0.042) and 180°/sec (p = 0.036), and ankle plantar flexors at 60o/sec (p = 0.044). A linear trend of increase in isokinetic strength with PTA level was observed for the eccentric strength of knee flexors at 60°/sec (p = 0.02) and 180°/sec (p = 0.03). Directional (R/L) asymmetries decreased with PTA, with this being mainly expressed in the concentric function of knee flexors at 180°/sec (p = 0.04) and at 300 °/sec (p = 0.03). These findings confirm the hypothesis of asymmetry in the strength adaptations that take place at the knee and ankle joint of soccer players mainly along with short and intermediate PTA. Players with a longer PTA seem to adopt a more balanced use of their lower extremities to cope with previously developed musculoskeletal asymmetries and possibly reduce injury risk. This has certain implications

  10. Subjective Age in Early Adolescence: Relationships with Chronological Age, Pubertal Timing, Desired Age, and Problem Behaviors

    ERIC Educational Resources Information Center

    Hubley, Anita M.; Arim, Rubab G.

    2012-01-01

    Subjective age generally refers to the age that one feels. In a cross-sectional questionnaire study of 245 adolescents ages 10-14 years, we examined (a) whether, and when, a cross-over in subjective age occurs, (b) differences in subjective age among pubertal timing groups, (c) correlations between subjective age and each of desired age and five…

  11. The impact of obesity on skeletal muscle strength and structure through adolescence to old age.

    PubMed

    Tomlinson, D J; Erskine, R M; Morse, C I; Winwood, K; Onambélé-Pearson, Gladys

    2016-06-01

    Obesity is associated with functional limitations in muscle performance and increased likelihood of developing a functional disability such as mobility, strength, postural and dynamic balance limitations. The consensus is that obese individuals, regardless of age, have a greater absolute maximum muscle strength compared to non-obese persons, suggesting that increased adiposity acts as a chronic overload stimulus on the antigravity muscles (e.g., quadriceps and calf), thus increasing muscle size and strength. However, when maximum muscular strength is normalised to body mass, obese individuals appear weaker. This relative weakness may be caused by reduced mobility, neural adaptations and changes in muscle morphology. Discrepancies in the literature remain for maximal strength normalised to muscle mass (muscle quality) and can potentially be explained through accounting for the measurement protocol contributing to muscle strength capacity that need to be explored in more depth such as antagonist muscle co-activation, muscle architecture, a criterion valid measurement of muscle size and an accurate measurement of physical activity levels. Current evidence demonstrating the effect of obesity on muscle quality is limited. These factors not being recorded in some of the existing literature suggest a potential underestimation of muscle force either in terms of absolute force production or relative to muscle mass; thus the true effect of obesity upon skeletal muscle size, structure and function, including any interactions with ageing effects, remains to be elucidated. PMID:26667010

  12. The impact of obesity on skeletal muscle strength and structure through adolescence to old age.

    PubMed

    Tomlinson, D J; Erskine, R M; Morse, C I; Winwood, K; Onambélé-Pearson, Gladys

    2016-06-01

    Obesity is associated with functional limitations in muscle performance and increased likelihood of developing a functional disability such as mobility, strength, postural and dynamic balance limitations. The consensus is that obese individuals, regardless of age, have a greater absolute maximum muscle strength compared to non-obese persons, suggesting that increased adiposity acts as a chronic overload stimulus on the antigravity muscles (e.g., quadriceps and calf), thus increasing muscle size and strength. However, when maximum muscular strength is normalised to body mass, obese individuals appear weaker. This relative weakness may be caused by reduced mobility, neural adaptations and changes in muscle morphology. Discrepancies in the literature remain for maximal strength normalised to muscle mass (muscle quality) and can potentially be explained through accounting for the measurement protocol contributing to muscle strength capacity that need to be explored in more depth such as antagonist muscle co-activation, muscle architecture, a criterion valid measurement of muscle size and an accurate measurement of physical activity levels. Current evidence demonstrating the effect of obesity on muscle quality is limited. These factors not being recorded in some of the existing literature suggest a potential underestimation of muscle force either in terms of absolute force production or relative to muscle mass; thus the true effect of obesity upon skeletal muscle size, structure and function, including any interactions with ageing effects, remains to be elucidated.

  13. Effects of Age, Gender and Educational Background on Strength of Motivation for Medical School

    ERIC Educational Resources Information Center

    Kusurkar, Rashmi; Kruitwagen, Cas; ten Cate, Olle; Croiset, Gerda

    2010-01-01

    The aim of this study was to determine the effects of selection, educational background, age and gender on strength of motivation to attend and pursue medical school. Graduate entry (GE) medical students (having Bachelor's degree in Life Sciences or related field) and Non-Graduate Entry (NGE) medical students (having only completed high school),…

  14. Aging, isometric strength and endurance, and cardiovascular responses to static effort.

    PubMed

    Petrofsky, J S; Lind, A R

    1975-01-01

    Previous studies on the relationship of age to isometric muscular strength are few, on isometric endurance rare, and on the physiological responses to static effort nonexistent. This investigation assessed the maximal handgrip strength, the duration of a fatiguing handgrip contraction at a tension of 40% of maximal strength and the heart rate and blood pressure during that contraction of 100 men aged from 22 to 62 yr. The subjects of this study were all men employed in a machine shop for a large aircraft corporation. The homogeneity of their occupations may well explain why, unlike previous reports, we found no change in muscular strength or muscular endurance with age. However, although heart rate increased during the contraction in all subjects, the increase in heart rate was greater in younger men. In contrast, while both systolic and diastolic blood pressures increased during the contraction in all subjects, the largest increase in systolic blood pressure was attained by the men in the older decades; there was no difference due to age in the diastolic blood pressures. The implications of these findings are discussed. PMID:1110248

  15. Motor effort training with low exercise intensity improves muscle strength and descending command in aging.

    PubMed

    Jiang, Changhao; Ranganathan, Vinoth K; Zhang, Junmei; Siemionow, Vlodek; Yue, Guang H

    2016-06-01

    This study explored the effect of high mental effort training (MET) and conventional strength training (CST) on increasing voluntary muscle strength and brain signal associated with producing maximal muscle force in healthy aging. Twenty-seven older adults (age: 75 ± 7.9 yr, 8 women) were assigned into 1 of 3 groups: MET group-trained with low-intensity (30% maximal voluntary contraction [MVC]) physical exercise combined with MET, CST group-trained with high-intensity muscle contractions, or control (CTRL) group-no training of any kind. MET and CST lasted for 12 weeks (5 sessions/week). The participants' elbow flexion strength of the right arm, electromyography (EMG), and motor activity-related cortical potential (MRCP) directly related to the strength production were measured before and after training. The CST group had the highest strength gain (17.6%, P <0.001), the MET group also had significant strength gain (13.8%, P <0.001), which was not statistically different from that of the CST group even though the exercise intensity for the MET group was only at 30% MVC level. The CTRL group did not have significant strength changes. Surprisingly, only the MET group demonstrated a significant augmentation in the MRCP (29.3%, P <0.001); the MRCP increase in CST group was at boarder-line significance level (12.11%, P = 0.061) and that for CTRL group was only 4.9% (P = 0.539). These results suggest that high mental effort training combined with low-intensity physical exercise is an effective method for voluntary muscle strengthening and this approach is especially beneficial for those who are physically weak and have difficulty undergoing conventional strength training.

  16. Motor effort training with low exercise intensity improves muscle strength and descending command in aging

    PubMed Central

    Jiang, Changhao; Ranganathan, Vinoth K.; Zhang, Junmei; Siemionow, Vlodek; Yue, Guang H.

    2016-01-01

    Abstract This study explored the effect of high mental effort training (MET) and conventional strength training (CST) on increasing voluntary muscle strength and brain signal associated with producing maximal muscle force in healthy aging. Twenty-seven older adults (age: 75 ± 7.9 yr, 8 women) were assigned into 1 of 3 groups: MET group—trained with low-intensity (30% maximal voluntary contraction [MVC]) physical exercise combined with MET, CST group—trained with high-intensity muscle contractions, or control (CTRL) group—no training of any kind. MET and CST lasted for 12 weeks (5 sessions/week). The participants’ elbow flexion strength of the right arm, electromyography (EMG), and motor activity-related cortical potential (MRCP) directly related to the strength production were measured before and after training. The CST group had the highest strength gain (17.6%, P <0.001), the MET group also had significant strength gain (13.8%, P <0.001), which was not statistically different from that of the CST group even though the exercise intensity for the MET group was only at 30% MVC level. The CTRL group did not have significant strength changes. Surprisingly, only the MET group demonstrated a significant augmentation in the MRCP (29.3%, P <0.001); the MRCP increase in CST group was at boarder-line significance level (12.11%, P = 0.061) and that for CTRL group was only 4.9% (P = 0.539). These results suggest that high mental effort training combined with low-intensity physical exercise is an effective method for voluntary muscle strengthening and this approach is especially beneficial for those who are physically weak and have difficulty undergoing conventional strength training. PMID:27310942

  17. Early Vascular Aging: A New Target for Hypertension Treatment.

    PubMed

    Papakatsika, Sofia; Stabouli, Stella; Antza, Christina; Kotsis, Vasilios

    2016-01-01

    Vascular aging represents a progressive procedure involving biochemical, enzymatic, and cellular changes of the vascular tree. Early vascular aging (EVA), is defined as the inappropriate for age of vascular damage. Increased for age arterial stiffness is a biomarker that should be considered as a cardiovascular (CV) risk factor that can be manipulated. EVA is a new tool for guidance in everyday clinical praxis for patients at increased CV risk or a positive family history of early onset of cardiovascular events, such as stroke or coronary artery disease. Understanding the mechanisms promoting or protecting from EVA, a process that is in close relationship with CV diseases. The role of hypertension treatment against the development of vascular damage is important and different strategies could have a considerable impact on future vascular health. PMID:26548304

  18. Early Vascular Aging: A New Target for Hypertension Treatment.

    PubMed

    Papakatsika, Sofia; Stabouli, Stella; Antza, Christina; Kotsis, Vasilios

    2016-01-01

    Vascular aging represents a progressive procedure involving biochemical, enzymatic, and cellular changes of the vascular tree. Early vascular aging (EVA), is defined as the inappropriate for age of vascular damage. Increased for age arterial stiffness is a biomarker that should be considered as a cardiovascular (CV) risk factor that can be manipulated. EVA is a new tool for guidance in everyday clinical praxis for patients at increased CV risk or a positive family history of early onset of cardiovascular events, such as stroke or coronary artery disease. Understanding the mechanisms promoting or protecting from EVA, a process that is in close relationship with CV diseases. The role of hypertension treatment against the development of vascular damage is important and different strategies could have a considerable impact on future vascular health.

  19. Analysis, prediction, and case studies of early-age cracking in bridge decks

    NASA Astrophysics Data System (ADS)

    ElSafty, Adel; Graeff, Matthew K.; El-Gharib, Georges; Abdel-Mohti, Ahmed; Mike Jackson, N.

    2016-06-01

    Early-age cracking can adversely affect strength, serviceability, and durability of concrete bridge decks. Early age is defined as the period after final setting, during which concrete properties change rapidly. Many factors can cause early-age bridge deck cracking including temperature change, hydration, plastic shrinkage, autogenous shrinkage, and drying shrinkage. The cracking may also increase the effect of freeze and thaw cycles and may lead to corrosion of reinforcement. This research paper presents an analysis of causes and factors affecting early-age cracking. It also provides a tool developed to predict the likelihood and initiation of early-age cracking of concrete bridge decks. Understanding the concrete properties is essential so that the developed tool can accurately model the mechanisms contributing to the cracking of concrete bridge decks. The user interface of the implemented computer Excel program enables the user to input the properties of the concrete being monitored. The research study and the developed spreadsheet were used to comprehensively investigate the issue of concrete deck cracking. The spreadsheet is designed to be a user-friendly calculation tool for concrete mixture proportioning, temperature prediction, thermal analysis, and tensile cracking prediction. The study also provides review and makes recommendations on the deck cracking based mainly on the Florida Department of Transportation specifications and Structures Design Guidelines, and Bridge Design Manuals of other states. The results were also compared with that of other commercially available software programs that predict early-age cracking in concrete slabs, concrete pavement, and reinforced concrete bridge decks. The outcome of this study can identify a set of recommendations to limit the deck cracking problem and maintain a longer service life of bridges.

  20. Adhesion strategy and early bond strengths of glass-fiber posts luted into root canals.

    PubMed

    Faria-e-Silva, André Luis; Mendonça, Adriano Augusto Melo; Garcez, Rosa Maria Viana de Bragança; Oliveira, Aline da Silva de; Moreira, Andressa Goicochea; Moraes, Rafael Ratto de

    2012-01-01

    This study investigated the effect of coinitiator solutions and self-adhesive resin cement on the early retention of glass-fiber posts. Cylindrical glass-fiber posts were luted into 40 incisor roots with different adhesion strategies (n = 10): SB2, Single Bond 2 + conventional resin cement (RelyX ARC); AP, Scotchbond Multipurpose Plus (SBMP) activator + primer + ARC; APC, SBMP activator + primer + catalyst + ARC; and UNI, self-adhesive cement (RelyX Unicem). Pull-out bond strength results at 10 min after cementation showed APC > UNI > SB2 = AP (P < 0.05). The adhesion strategy significantly affected early bonding to root canals.

  1. Effect of early water exposure on the strength of glass ionomer restoratives.

    PubMed

    Wang, X Y; Yap, Adrian U J; Ngo, H C

    2006-01-01

    This study examined the effect of early water exposure on the shear strength of a spectrum of glass ionomer restoratives. The materials evaluated included conventional auto-cured (Fuji II [FT], GC), resin-modified light-cured (Fuji II LC [FL]) and, recently introduced, high strength auto-cured (Fuji IX GP Fast [FN], GC; Ketac Molar Quick [KQ], 3M-ESPE; Ketac Molar [KM], 3M-ESPE) cements. Sixteen specimens (8.7-mm in diameter and 1-mm thick) of each material were prepared in metal washers and randomly divided into 2 groups. The specimens were allowed to set for 6 minutes between polyester strips, to ensure completion of the initial set. The strips were subsequently removed, and the surfaces of Group 1 specimens were coated on both sides with resin (Fuji Coat LC, GC) and light cured for 10 seconds. Group 2 specimens were left uncoated. All specimens were then conditioned in distilled water at 37 degrees C for 4 weeks. After conditioning, the specimens were restrained with a torque of 2.5 Nm and subjected to shear punch testing using a 2-mm diameter punch at a crosshead speed of 0.5-mm/minute. The mean shear strengths of the materials were computed and subjected to Independent Samples t-test and ANOVA/Scheffe's tests at significance level 0.05. Mean strength ranged from 78.34 to 99.36 MPa and 79.88 to 95.78 MPa for Groups 1 and 2, respectively. No significant difference in shear strength was observed between the 2 groups. For both groups, KM and KQ were significantly stronger than FT. Contrary to current teaching, early exposure to water did not weaken glass ionomer restoratives. A marginal increase in strength was actually observed for some materials. PMID:17024947

  2. Leg strength declines with advancing age despite habitual endurance exercise in active older adults.

    PubMed

    Marcell, Taylor J; Hawkins, Steven A; Wiswell, Robert A

    2014-02-01

    Age-associated loss of muscle mass (sarcopenia) and strength (dynapenia) is associated with a loss of independence that contributes to falls, fractures, and nursing home admissions, whereas regular physical activity has been suggested to offset these losses. The purpose of this study was to evaluate the effect of habitual endurance exercise on muscle mass and strength in active older adults. A longitudinal analysis of muscle strength (≈4.8 years apart) was performed on 59 men (age at start of study: 58.6 ± 7.3 years) and 35 women (56.9 ± 8.2 years) who used endurance running as their primary mode of exercise. There were no changes in fat-free mass although body fat increased minimally (1.0-1.5%). Training volume (km·wk, d·wk) decreased in both the men and women. There was a significant loss of both isometric knee extension (≈5% per year) and knee flexion (≈3.6% per year) strength in both the men and women. However, there was no significant change in either isokinetic concentric or eccentric torque of the knee extensors. Our data demonstrated a significant decline in isometric knee extensor and knee flexor strength although there were no changes in body mass in this group of very active older men and women. Our data support newer exercise guidelines for older Americans suggesting resistance training be an integral component of a fitness program and that running alone was not sufficient to prevent the loss in muscle strength (dynapenia) with aging.

  3. Gender, Age, and Behavior Differences in Early Adolescent Worry

    ERIC Educational Resources Information Center

    Brown, Stephen L.; Teufel, James A.; Birch, David A.; Kancherla, Vijaya

    2006-01-01

    Early adolescents in the United States are increasingly exposed to a culture of worrisome messages. A degree of adolescent worry is normal, but the likelihood of a young person being anxious or depressed increases with the perceived number of worries. This study examined the effect of age, gender, and worry behavior on frequency of 8 adolescent…

  4. Executive Function in Very Preterm Children at Early School Age

    ERIC Educational Resources Information Center

    Aarnoudse-Moens, Cornelieke S. H.; Smidts, Diana P.; Oosterlaan, Jaap; Duivenvoorden, Hugo J.; Weisglas-Kuperus, Nynke

    2009-01-01

    We examined whether very preterm ([less than or equal to] 30 weeks gestation) children at early school age have impairments in executive function (EF) independent of IQ and processing speed, and whether demographic and neonatal risk factors were associated with EF impairments. A consecutive sample of 50 children (27 boys and 23 girls) born very…

  5. Learning your own strength: winner and loser effects should change with age and experience

    PubMed Central

    Fawcett, Tim W.; Johnstone, Rufus A.

    2010-01-01

    Winner and loser effects, in which the outcome of an aggressive encounter influences the tendency to escalate future conflicts, have been documented in many taxa, but we have limited understanding of why they have evolved. One possibility is that individuals use previous victories and defeats to assess their fighting ability relative to others. We explored this idea by modelling a population of strong and weak individuals that do not know their own strength, but keep track of how many fights they have won. Under these conditions, adaptive behaviour generates clear winner and loser effects: individuals who win fights should escalate subsequent conflicts, whereas those who lose should retreat from aggressive opponents. But these effects depend strongly on age and experience. Young, naive individuals should show highly aggressive behaviour and pronounced loser effects. For these inexperienced individuals, fighting is especially profitable because it yields valuable information about their strength. Aggression should then decline as an individual ages and gains experience, with those who lose fights becoming more submissive. Older individuals, who have a better idea of their own strength, should be more strongly influenced by victories than losses. In conclusion, we predict that both aggressiveness and the relative magnitude of winner and loser effects should change with age, owing to changes in how individuals perceive their own strength. PMID:20053644

  6. Fracture Strength of Aged Monolithic and Bilayer Zirconia-Based Crowns

    PubMed Central

    Lameira, Deborah Pacheco; Silva, Wilkens Aurélio Buarque e; Silva, Frederico Andrade e; De Souza, Grace M.

    2015-01-01

    The purpose of this study was to evaluate the effect of design and surface finishing on fracture strength of yttria-tetragonal zirconia polycrystal (Y-TZP) crowns in monolithic (1.5 mm thickness) and bilayer (0.8 mm zirconia coping and 0.7 mm porcelain veneer) configuration after artificial aging. Bovine incisors received crown preparation and Y-TZP crowns were manufactured using CAD/CAM technique, according to the following groups (n = 10): Polished monolithic zirconia crowns (PM); Glazed monolithic zirconia crowns (GM); Bi-layer crowns (BL). Crowns were cemented with resin cement, submitted to artificial aging in a chewing simulator (2.5 million cycles/80 N/artificial saliva/37°C), and tested for fracture strength. Two remaining crowns referring to PM and GM groups were submitted to a chemical composition analysis to measure the level of yttrium after aging. One-way ANOVA and Tukey's test (P = .05) indicated that monolithic zirconia crowns presented similar fracture strength (PM = 3476.2 N ± 791.7; GM = 3561.5 N ± 991.6), which was higher than bilayer crowns (2060.4 N ± 810.6). There was no difference in the yttrium content among the three surfaces evaluated in the monolithic crowns. Thus, monolithic zirconia crowns present higher fracture strength than bilayer veneered zirconia after artificial aging and surface finishing does not affect their fracture strength. PMID:26576423

  7. Effects of age, gender and educational background on strength of motivation for medical school.

    PubMed

    Kusurkar, Rashmi; Kruitwagen, Cas; ten Cate, Olle; Croiset, Gerda

    2010-08-01

    The aim of this study was to determine the effects of selection, educational background, age and gender on strength of motivation to attend and pursue medical school. Graduate entry (GE) medical students (having Bachelor's degree in Life Sciences or related field) and Non-Graduate Entry (NGE) medical students (having only completed high school), were asked to fill out the Strength of Motivation for Medical School (SMMS) questionnaire at the start of medical school. The questionnaire measures the willingness of the medical students to pursue medical education even in the face of difficulty and sacrifice. GE students (59.64 ± 7.30) had higher strength of motivation as compared to NGE students (55.26 ± 8.33), so did females (57.05 ± 8.28) as compared to males (54.30 ± 8.08). 7.9% of the variance in the SMMS scores could be explained with the help of a linear regression model with age, gender and educational background/selection as predictor variables. Age was the single largest predictor. Maturity, taking developmental differences between sexes into account, was used as a predictor to correct for differences in the maturation of males and females. Still, the gender differences prevailed, though they were reduced. Pre-entrance educational background and selection also predicted the strength of motivation, but the effect of the two was confounded. Strength of motivation appears to be a dynamic entity, changing primarily with age and maturity and to a small extent with gender and experience.

  8. The impact of early nutrition on the ageing trajectory.

    PubMed

    Tarry-Adkins, Jane L; Ozanne, Susan E

    2014-05-01

    Epidemiological studies, including those in identical twins, and in individuals in utero during periods of famine have provided robust evidence of strong correlations between low birth-weight and subsequent risk of disease in later life, including type 2 diabetes (T2D), CVD, and metabolic syndrome. These and studies in animal models have suggested that the early environment, especially early nutrition, plays an important role in mediating these associations. The concept of early life programming is therefore widely accepted; however the molecular mechanisms by which early environmental insults can have long-term effects on a cell and consequently the metabolism of an organism in later life, are relatively unclear. So far, these mechanisms include permanent structural changes to the organ caused by suboptimal levels of an important factor during a critical developmental period, changes in gene expression caused by epigenetic modifications (including DNA methylation, histone modification and microRNA) and permanent changes in cellular ageing. Many of the conditions associated with early-life nutrition are also those which have an age-associated aetiology. Recently, a common molecular mechanism in animal models of developmental programming and epidemiological studies has been development of oxidative stress and macromolecule damage, specifically DNA damage and telomere shortening. These are phenotypes common to accelerated cellular ageing. Thus, this review will encompass epidemiological and animal models of developmental programming with specific emphasis on cellular ageing and how these could lead to potential therapeutic interventions and strategies which could combat the burden of common age-associated disease, such as T2D and CVD. PMID:24411102

  9. The effect of aging, temperature and brine composition on the mechanical strength of chalk

    NASA Astrophysics Data System (ADS)

    Korsnes, Reidar Inge; Nermoen, Anders; Stødle, Trond; Vika Storm, Eirik; Vadla Madland, Merete

    2014-05-01

    Chalk strength has been of great focus for several research communities since the 1980s when the Ekofisk subsidence problem was discovered. Sea water injection was initiated in 1987 to improve the oil production and to re-pressurize the reservoirs to halt the subsidence. The oil production was improved significantly, but the reservoir compaction in the water saturated regions continued, in contrast to the regions with no water breakthrough. This observation indicates a water weakening effect of the chalk. Extensive studies have been performed during the last decades to enlighten how the brine chemistry alters the rock mechanical properties. These studies have shown that the elastic bulk modulus, yield strength, creep and the deformation rate at constant stress conditions depend on the pore fluid composition. In general, the injected brine is in non-equilibrium with the rock surface inducing alteration of the rock mineralogy. In this study we examined two aspects of the mechanical strength, namely the bulk modulus and the onset of yield during hydrostatic stress loading with 0.7 MPa pore pressure. The test program consisted of aged and un-aged cores, ambient and 130°C test temperature, and four brine compositions: MgCl2, NaCl, Na2SO4, and synthetic sea water (SSW) at ion strengths of 0.657 M. The aging was performed by submerging saturated cores in a closed container with the respective test brine for three weeks at 130°C. Un-aged cores were saturated the same day as they were tested. For each brine composition we present four test setups; (a) aged and tested at 130°C, (b) aged and tested at ambient temperature, (c) un-aged and tested at 130°C, and (d) un-aged and tested at ambient conditions. The main results from our study are: 1. By using NaCl and MgCl2 as saturating brines, neither the test temperature nor the aging procedure affected the yield stress and bulk modulus significantly. 2. Using Na2SO4, the yield point and bulk moduli were reduced if the core

  10. Loss of Nfkb1 leads to early onset aging

    PubMed Central

    Crawley, Clayton D.; Cahill, Kirk E.; Pytel, Peter; Liang, Hua; Kang, Shijun; Weichselbaum, Ralph R.; Yamini, Bakhtiar

    2014-01-01

    NF-(B is a major regulator of age-dependent gene expression and the p50/NF-(B1 subunit is an integral modulator of NF-(B signaling. Here, we examined Nfkb1−/− mice to investigate the relationship between this subunit and aging. Although Nfkb1−/− mice appear similar to littermates at six months of age, by 12 months they have a higher incidence of several observable age-related phenotypes. In addition, aged Nfkb1−/− animals have increased kyphosis, decreased cortical bone, increased brain GFAP staining and a decrease in overall lifespan compared to Nfkb1+/+. In vitro, serially passaged primary Nfkb1−/− MEFs have more senescent cells than comparable Nfkb1+/+ MEFs. Also, Nfkb1−/− MEFs have greater amounts of phospho-H2AX foci and lower levels of spontaneous apoptosis than Nfkb1+/+, findings that are mirrored in the brains of Nfkb1−/− animals compared to Nfkb1+/+. Finally, in wildtype animals a substantial decrease in p50 DNA binding is seen in aged tissue compared to young. Together, these data show that loss of Nfkb1 leads to early animal aging that is associated with reduced apoptosis and increased cellular senescence. Moreover, loss of p50 DNA binding is a prominent feature of aged mice relative to young. These findings support the strong link between the NF-(B pathway and mammalian aging. PMID:25553648

  11. Loss of Nfkb1 leads to early onset aging.

    PubMed

    Bernal, Giovanna M; Wahlstrom, Joshua S; Crawley, Clayton D; Cahill, Kirk E; Pytel, Peter; Liang, Hua; Kang, Shijun; Weichselbaum, Ralph R; Yamini, Bakhtiar

    2014-11-01

    NF-κB is a major regulator of age-dependent gene expression and the p50/NF-κB1 subunit is an integral modulator of NF-κB signaling. Here, we examined Nfkb1-/- mice to investigate the relationship between this subunit and aging. Although Nfkb1-/- mice appear similar to littermates at six months of age, by 12 months they have a higher incidence of several observable age-related phenotypes. In addition, aged Nfkb1-/- animals have increased kyphosis, decreased cortical bone, increased brain GFAP staining and a decrease in overall lifespan compared to Nfkb1+/+. In vitro, serially passaged primary Nfkb1-/- MEFs have more senescent cells than comparable Nfkb1+/+ MEFs. Also, Nfkb1-/- MEFs have greater amounts of phospho-H2AX foci and lower levels of spontaneous apoptosis than Nfkb1+/+, findings that are mirrored in the brains of Nfkb1-/- animals compared to Nfkb1+/+. Finally, in wildtype animals a substantial decrease in p50 DNA binding is seen in aged tissue compared to young. Together, these data show that loss of Nfkb1 leads to early animal aging that is associated with reduced apoptosis and increased cellular senescence. Moreover, loss of p50 DNA binding is a prominent feature of aged mice relative to young. These findings support the strong link between the NF-κB pathway and mammalian aging.

  12. Age, sex and personality in early cannabis use.

    PubMed

    Muro I Rodríguez, A

    2015-06-01

    Previous studies analysing personality and cannabis use in adult samples suggest that cannabis users show significant higher levels of impulsivity, sensation seeking and schizotypy. However, there are few studies exploring this relationship in adolescence using psychobiological models of personality. Given the relevance of identifying individual differences that lead adolescents to early cannabis use to prevent future health problems, the present study aimed to explore the relationship between age, sex, personality and early cannabis use using a psychobiological model of personality in a sample of 415 students (51.8% boys) from 12 to 18 years. Chi(2) tests showed significant higher prevalence of cannabis use in boys and in the group aged 15-18 years. Multiple analysis of variance showed significant higher scores in psychoticism, sensation seeking and in all its subscales in cannabis users group, while an interaction with age was found for extraversion and neuroticism: cannabis users scored higher than non-users in the youngest group (12-14 years) but lower in the oldest group in both dimensions. Finally, regression analysis showed that narrower traits of sensation seeking (experience seeking and disinhibition) were the most associated to early cannabis use. Results are discussed in terms of early cannabis users' personality profiles and in terms of the self-medication theory.

  13. Where is ELSA? The early to late shift in aging.

    PubMed

    Dew, Ilana T Z; Buchler, Norbou; Dobbins, Ian G; Cabeza, Roberto

    2012-11-01

    Studies of cognitive and neural aging have recently provided evidence of a shift from an early- to late-onset cognitive control strategy, linked with temporally extended activity in the prefrontal cortex (PFC). It has been uncertain, however, whether this age-related shift is unique to PFC and executive control tasks or whether the functional location might vary depending on the particular cognitive processes that are altered. The present study tested whether an early-to-late shift in aging (ELSA) might emerge in the medial temporal lobes (MTL) during a protracted context memory task comprising both anticipatory cue (retrieval preparation) and retrieval probe (retrieval completion) phases. First, we found reduced MTL activity in older adults during the early retrieval preparation phase coupled with increased MTL activity during the late retrieval completion phase. Second, we found that functional connectivity between MTL and PFC regions was higher during retrieval preparation in young adults but higher during retrieval completion in older adults, suggesting an important interactive relationship between the ELSA pattern in MTL and PFC. Taken together, these results critically suggest that aging results in temporally lagged activity even in regions not typically associated with cognitive control, such as the MTL. PMID:22114083

  14. Strength Properties of Aged Poled Lead Zirconate Titanate Subjected to Electromechanical Loadings

    SciTech Connect

    Zhang, Kewei; Zeng, Fan W; Wang, Hong; Lin, Hua-Tay

    2012-01-01

    Electric field and aging time are two important factors that affect the mechanical strength and long-term reliability of lead zirconate titanate or PZT actuators. In the present work, a commercial PZT-5A aged four years was examined using ball-on-ring (BoR) mechanical testing under coupled electric fields. The electric field range of -3E{sub c} to +3E{sub c} (E{sub c}, coercive electric field) was studied (i.e., -3E{sub c}, -E{sub c}, 0, +E{sub c}, +2E{sub c}, and +3E{sub c}) with a controlled electric loading path. A Weibull distribution was used to interpret the mechanical strength data. With an electric field preloaded from 0 to -3E{sub c}, it was found that subsequent increases in the electric field resulted in an asymmetrical V-shaped curve of mechanical strength against the electric field. The bottom of the V curve was located near the zero electric field level. Microscopy analysis showed that pores were the strength limiter for the tested PZT under electromechanical loadings.

  15. lsokinetic Shoulder Strength of High School and College-Aged Pitchers*.

    PubMed

    Alderink, G J; Kuck, D J

    1986-01-01

    The purpose of this study was to determine the isokinetic strength of the shoulders of high school and college-aged baseball pitchers. Twenty-four athletes ranging from 14 to 21 years of age volunteered for this study. The Cybex(R) II and U.B.X. T. were utilized to test the strength of the shoulder abductors/adductors, flexors/extensors, horizontal abductors/adductors, and external/internal rotators at 90, 120, 2 10, and 300 degrees /sec. There were no consistent differences between dominant and nondominant arm strength, except for the shoulder adductors and shoulder extensors. The shoulder abductors and flexors were approximately 50% as strong as the adductors and extensors, respectively. There was a 1:1 ratio between the horizontal abductors/ adductors. The external rotators were approximately two-thirds as strong as the internal rotators. A positive correlation was found between total body weight and shoulder strength. This information is relatively new to the literature and should provide clinicians with some training and rehabilitation guidelines. J Orthop Sports Phys Ther 1986;7(4):163-172.

  16. Assessment of handgrip strength in preschool children aged 3 to 5 years.

    PubMed

    Sanchez-Delgado, G; Cadenas-Sanchez, C; Mora-Gonzalez, J; Martinez-Tellez, B; Chillón, P; Löf, M; Ortega, F B; Ruiz, J R

    2015-11-01

    We investigated whether there is an optimal grip span for determining the maximum handgrip strength in preschool children and if it is influenced by gender, age, or hand size. A total of 292 preschool children (3-5 years; 59.2% boys) carried out the handgrip strength test with different grip spans (4.0, 4.5, 5.0, 5.5, and 6.0 cm). The hand size was also measured. We also determined the reliability of the optimal grip span in another group of children (n = 56, 57% boys) who did the test twice, with a 3-hour difference between tests. The results showed that 4.0 cm is the optimal grip span to determine the maximum handgrip strength in preschool children. This result applied to both genders, all age groups, and hand sizes. Paired t-tests showed no significant differences between test and retest. These findings may guide clinicians and researchers in selecting the optimal grip span when measuring handgrip strength in preschool children.Level IV.

  17. A Study of Bar Strengths in Early-Type Disk Galaxies

    NASA Astrophysics Data System (ADS)

    Buta, Ronald J.; Laurikainen, Eija; Salo, Heikki; Knapen, Johan H.

    2009-02-01

    Angular momentum exchange between a bar and a massive halo is thought to be responsible for producing strong bars in disk galaxies (Athanassoula, 2003), while gas transport to the center is believed to weaken or even dissolve bars (Bournaud and Combes 2002). We are carrying out a systematic survey of early-type disk galaxies with the main emphasis to derive the distribution of their bar strengths and to examine their Fourier amplitude properties. We propose to use FLAMINGOS with the KPNO 2.1m to obtain 2.2(micron) K_s-band observations of 16 galaxies for the ``Near-Infrared S0 Survey", a project already in progress to measure the bulge, disk, and bar properties of a statistically well-defined sample of 184 galaxies in the type range S0^- to Sa, including some possibly mis-classified elliptical galaxies. The principal goals of the survey, which was started 5 years ago and is now 90% completed, are to allow us to (1) compare relative Fourier near- IR intensity profiles of observed early-type galaxy bars with equivalent Fourier mass profiles of various Athanassoula models; (2) derive the distribution of bar strengths for the early-type sample and compare it with the known distribution for spirals; and (3) examine the properties of bulges and disks in early-type galaxies in order to better understand the origin of bulges (classical verus pseudo) in such galaxies. Our study is the first attempt to quantify bar strength in S0 galaxies. We are asking for enough KPNO 2.1m time to help complete our survey.

  18. Varying contributions of growth and ageing to racial and sex differences in femoral neck structure and strength in old age.

    PubMed

    Wang, Xiao-Fang; Duan, Yunbo; Beck, Thomas J; Seeman, Ego

    2005-06-01

    The structural basis of racial and sex differences in femoral neck (FN) fragility in old age was assessed in a cross-sectional study of 829 healthy Chinese and 1181 healthy Caucasian subjects aged 18 to 93 years in Melbourne, Australia. We measured FN bone mineral density (BMD), periosteal diameter, and estimated endocortical diameter, cortical thickness, volumetric BMD (vBMD), section modulus, and buckling ratio using dual X-ray absorptiometry. Racial and sex differences in structural and strength indices were adjusted for age, bone length and body weight and were expressed in standard deviation (SD) unit. In young adulthood, Chinese women had a 0.85 SD narrower FN, a 0.47 SD thinner cortex and a 0.79 SD shorter FN axis length (FNAL) than Caucasian women. Across age, Chinese and Caucasian women had similar increments in endocortical and periosteal diameters and similar decrements in cortical thickness and vBMD (both approximately 20%). In young adult males, FN periosteal diameter did not differ by race, but cortical thickness was 0.35 SD lower in Chinese than Caucasians. Across age, increments in periosteal and endocortical diameters were less in Chinese than Caucasian men so cortical thickness and vBMD diminished less in Chinese than in Caucasian men. In both races, young adult women had narrower FN than men. As Chinese women had a greater increment in periosteal diameter than Chinese men across age, the sex difference in FN periosteal diameter established in young adulthood diminished in old age. As Caucasian men had a greater increment in periosteal diameter than Caucasian women, the sex difference in FN periosteal diameter established in young adulthood increased with age. In old age, for both sexes, Chinese had a higher fracture risk in bending than Caucasians, but a lower fracture risk by buckling. For both races, women had a higher fracture risk in bending than men. Racial and sexual dimorphism in the absolute and relative behavior of the periosteal and

  19. Clinical Implications for Muscle Strength Differences in Women of Different Age and Racial Groups: The WIN Study

    PubMed Central

    Trudelle-Jackson, Elaine; Ferro, Emerenciana; Morrow, James R.

    2011-01-01

    Background Reduction in muscle strength is strongly associated with functional decline in women, and women with lower quadriceps strength adjusted for body weight are more likely to develop knee osteoarthritis. Objective To compare body weight--adjusted strength among women of different age/racial groups. Study Design Cross-sectional study of muscle strength in 918 women aged 20--83 (M ± SD = 52 ± 13). Methods An orthopedic examination was conducted including measurement of handgrip and lower extremity strength (hip abductors/external rotators, knee flexors/extensors). Data were grouped into young (20--39 years, n = 139), middle (40--54 years, n = 300), and older (55+ years, n = 424) ages for white (n = 699) and African American (AA) (n = 164) women. Means and standard deviations for strength adjusted for body weight were calculated for each age and racial group and compared using 2-way multivariate analysis of variance and post hoc tests. Results No significant age-by-race interaction (P = .092) but significant main effects for age and race (P < .001). Pairwise comparisons revealed significant differences in knee extensor and flexor strength between all age groups. For grip and hip external rotator strength, significant differences were found between the middle and older groups. Differences in hip abductor strength were found between the young and middle-aged groups. AA women had lower strength than white women in all muscle groups (P < .05) except hip external rotators. Conclusions Strength decreased with age in all muscle groups but magnitude of decrease varied by muscle. Strengthening programs should target different muscles, depending on a woman's age and race. PMID:21666779

  20. Effects of age and dietary soybean oil level on eggshell quality, bone strength and blood biochemistry in laying hens.

    PubMed

    Jiang, S; Cui, L Y; Hou, J F; Shi, C; Ke, X; Yang, L C; Ma, X P

    2014-01-01

    The objective of the study was to investigate the differences in eggshell quality, bone quality and serum bone biochemistry markers associated with changes in age and dietary soybean oil levels in laying hens. A total of 54, 19-week-old Hy-Line Brown laying hens were housed in 18 battery cages (3 birds/cage) and randomly divided into three diet treatments for 90 d: control-fat (CF, 1.9% soybean oil), moderate-fat (MF, 7% soybean oil) and high-fat (HF, 10% soybean oil). The hens' body weights (BW), egg production, egg weights, eggshell thickness and femoral diameter were higher at d 90 than at d 60 or d 30. Meanwhile, feed intake, relative bone weights, all bone strength parameters and serum Ca were lower at d 90 or 60 than at d 30. Compared to the CF hens, the feed intake, BW, abdominal fat pad weights and serum alkaline phosphatase activity were elevated in MF or HF hens. The eggshell thickness, relative femoral and tibial weight, femoral stiffness, femoral modulus, tibial mixed force and serum calcium and phosphorus levels were lower in MF or HF hens than CF hens. These findings suggest that bone loss in caged hens starts from an early stage of the laying period, and dietary oil (particularly with diets over 10% soybean oil) has harmful effects on eggshell quality, bone strength and bone mineralisation from an early stage of the laying period.

  1. Effect of simulated early weight bearing on micromotion and pullout strength of uncemented distal femoral stems.

    PubMed

    Barr, Jennifer S; White, Jedediah K; Punt, Stephanie E W; Conrad, Ernest U; Ching, Randal P

    2015-05-01

    The effect of simulated early weight bearing on both micromotion and pullout strength of uncemented distal femoral stems was evaluated in this study. The effect of stem endosteal contact and bone quality on implant pullout strength was also analyzed. A randomized matched-pair study was performed using 8 bilateral pairs of fresh human cadaveric femoral specimens. Each specimen pair was dual-energy x-ray absorptiometry scanned, uniformly implanted, fluoroscopically imaged, and randomly assigned to the cycled or uncycled group. The cycled group received 5000 cycles of axial compressive loading (to 700 N) and the contralateral side was not cycled. Micromotion was monitored during cycling and compared with a failure threshold (150 µm), and all implants underwent direct axial distraction (pullout) testing. During cycling, minimal micromotion was observed with an asymptotic decrease in differential motion between the first and last 50 cycles. Both cycled and uncycled groups demonstrated no statistical difference in average pullout force (4888±2124 N vs 4367±1154 N; P=.43). The percentage of cortical contact for each implant was determined from panoramic fluoroscopy images using digital image analysis software. Contact area for the distal third of the stem showed the highest correlation with pullout force and with predicting pullout force. Bone quality did not correlate with pullout force (r(2)=0.367) or stem contact area (r(2)=0.394). In sum, press-fit uncemented femoral stems did not loosen or demonstrate decreased pullout strength with early weight bearing simulated by cyclical axial compressive loading.

  2. Titanium dioxide nanoparticles: Impact of increasing ionic strength during synthesis, reflux, and hydrothermal aging

    SciTech Connect

    Isley, Sara L.; Jordan, David S.; Penn, R. Lee

    2009-01-08

    This work investigates the role of ionic strength during synthesis, reflux, and hydrothermal aging of sol-gel synthesized titanium dioxide. Research presented here uses X-ray diffraction data and Rietveld refinements to quantify anatase, brookite, and rutile phases as functions of synthetic and aging variables. In addition, the Scherrer equation is used to obtain average crystallite sizes for each phase quantified. Results presented in this work demonstrate that the most control over the sol-gel products can be obtained by modifying the pH during hydrolysis. In addition, while varying the ionic strength during reflux and hydrothermal aging can result in enhanced control over the crystalline phase and crystallite size, the most control can be achieved by varying the ionic strength during synthesis. Finally, sol-gel synthesis at low pH (-0.6) and high-chloride concentration (3 M NaCl) produced a heterogeneous sample composed of nanocrystalline anatase (3.8 nm) and rutile (2.9 nm)

  3. Moulding Faces at an Early Age-A Case Series

    PubMed Central

    Sunny, Sunil; Mathew, Neethu; Parambath, Anvar Kizhakke; Madhusudanan, Amla

    2016-01-01

    Certain malocclusions have to be treated at an early age to avoid surgeries for the correction in the future. Introduction of functional appliances has reduced the elimination and correction of skeletal as well as dental discrepancies. Proper case selection taking into consideration skeletal and dental age with the use of various diagnostic aids helps us to identify and treat the malocclusions before it is too late. In this case series, we report three patients with skeletal jaw malrelationship treated with functional and orthopaedic appliances. PMID:27656599

  4. Moulding Faces at an Early Age-A Case Series.

    PubMed

    Sunny, Sunil; Thomas, Rinu; Mathew, Neethu; Parambath, Anvar Kizhakke; Madhusudanan, Amla

    2016-08-01

    Certain malocclusions have to be treated at an early age to avoid surgeries for the correction in the future. Introduction of functional appliances has reduced the elimination and correction of skeletal as well as dental discrepancies. Proper case selection taking into consideration skeletal and dental age with the use of various diagnostic aids helps us to identify and treat the malocclusions before it is too late. In this case series, we report three patients with skeletal jaw malrelationship treated with functional and orthopaedic appliances. PMID:27656599

  5. Tooth loss early in life accelerates age-related bone deterioration in mice.

    PubMed

    Kurahashi, Minori; Kondo, Hiroko; Iinuma, Mitsuo; Tamura, Yasuo; Chen, Huayue; Kubo, Kin-ya

    2015-01-01

    Both osteoporosis and tooth loss are health concerns that affect many older people. Osteoporosis is a common skeletal disease of the elderly, characterized by low bone mass and microstructural deterioration of bone tissue. Chronic mild stress is a risk factor for osteoporosis. Many studies showed that tooth loss induced neurological alterations through activation of a stress hormone, corticosterone, in mice. In this study, we tested the hypothesis that tooth loss early in life may accelerate age-related bone deterioration using a mouse model. Male senescence-accelerated mouse strain P8 (SAMP8) mice were randomly divided into control and toothless groups. Removal of the upper molar teeth was performed at one month of age. Bone response was evaluated at 2, 5 and 9 months of age. Tooth loss early in life caused a significant increase in circulating corticosterone level with age. Osteoblast bone formation was suppressed and osteoclast bone resorption was activated in the toothless mice. Trabecular bone volume fraction of the vertebra and femur was decreased in the toothless mice with age. The bone quality was reduced in the toothless mice at 5 and 9 months of age, compared with the age-matched control mice. These findings indicate that tooth loss early in life impairs the dynamic homeostasis of the bone formation and bone resorption, leading to reduced bone strength with age. Long-term tooth loss may have a cumulative detrimental effect on bone health. It is important to take appropriate measures to treat tooth loss in older people for preventing and/or treating senile osteoporosis.

  6. Identification of morphological markers of sarcopenia at early stage of aging in skeletal muscle of mice.

    PubMed

    Sayed, Ramy K A; de Leonardis, Erika Chacin; Guerrero-Martínez, José A; Rahim, Ibtissem; Mokhtar, Doaa M; Saleh, Abdelmohaimen M; Abdalla, Kamal E H; Pozo, María J; Escames, Germaine; López, Luis C; Acuña-Castroviejo, Darío

    2016-10-01

    The gastrocnemius muscle (GM) of young (3months) and aged (12months) female wild-type C57/BL6 mice was examined by light and electron microscopy, looking for the presence of structural changes at early stage of the aging process. Morphometrical parameters including body and gastrocnemius weights, number and type of muscle fibers, cross section area (CSA), perimeter, and Feret's diameter of single muscle fiber, were measured. Moreover, lengths of the sarcomere, A-band, I-band, H-zone, and number and CSA of intermyofibrillar mitochondria (IFM), were also determined. The results provide evidence that 12month-old mice had significant changes on skeletal muscle structure, beginning with the reduction of gastrocnemius weight to body weight ratio, compatible with an early loss of skeletal muscle function and strength. Moreover, light microscopy revealed increased muscle fibers size, with a significant increase on their CSA, perimeter, and diameter of both type I and type II muscle fibers, and a reduction in the percentage of muscle area occupied by type II fibers. Enhanced connective tissue infiltrations, and the presence of centrally nucleated muscle fibers, were also found in aged mice. These changes may underlie an attempt to compensate the loss of muscle mass and muscle fibers number. Furthermore, electron microscopy discovered a significant age-dependent increase in the length of sarcomeres, I and H bands, and reduction on the overlapped actin/myosin length, supporting contractile force loss with age. Electron microscopy also showed an increased number and CSA of IFM with age, which may reveal more endurance at 12months of age. Together, mice at early stage of aging already show significant changes in gastrocnemius muscle morphology and ultrastructure that are suggestive of the onset of sarcopenia.

  7. Identification of morphological markers of sarcopenia at early stage of aging in skeletal muscle of mice.

    PubMed

    Sayed, Ramy K A; de Leonardis, Erika Chacin; Guerrero-Martínez, José A; Rahim, Ibtissem; Mokhtar, Doaa M; Saleh, Abdelmohaimen M; Abdalla, Kamal E H; Pozo, María J; Escames, Germaine; López, Luis C; Acuña-Castroviejo, Darío

    2016-10-01

    The gastrocnemius muscle (GM) of young (3months) and aged (12months) female wild-type C57/BL6 mice was examined by light and electron microscopy, looking for the presence of structural changes at early stage of the aging process. Morphometrical parameters including body and gastrocnemius weights, number and type of muscle fibers, cross section area (CSA), perimeter, and Feret's diameter of single muscle fiber, were measured. Moreover, lengths of the sarcomere, A-band, I-band, H-zone, and number and CSA of intermyofibrillar mitochondria (IFM), were also determined. The results provide evidence that 12month-old mice had significant changes on skeletal muscle structure, beginning with the reduction of gastrocnemius weight to body weight ratio, compatible with an early loss of skeletal muscle function and strength. Moreover, light microscopy revealed increased muscle fibers size, with a significant increase on their CSA, perimeter, and diameter of both type I and type II muscle fibers, and a reduction in the percentage of muscle area occupied by type II fibers. Enhanced connective tissue infiltrations, and the presence of centrally nucleated muscle fibers, were also found in aged mice. These changes may underlie an attempt to compensate the loss of muscle mass and muscle fibers number. Furthermore, electron microscopy discovered a significant age-dependent increase in the length of sarcomeres, I and H bands, and reduction on the overlapped actin/myosin length, supporting contractile force loss with age. Electron microscopy also showed an increased number and CSA of IFM with age, which may reveal more endurance at 12months of age. Together, mice at early stage of aging already show significant changes in gastrocnemius muscle morphology and ultrastructure that are suggestive of the onset of sarcopenia. PMID:27435496

  8. Ages and Ages: The Multiplication of Children's "Ages" in Early Twentieth-Century Child Psychology

    ERIC Educational Resources Information Center

    Beauvais, Clementine

    2016-01-01

    This paper explores the trend, between 1905 and the late 1920s in UK and US child psychology, of "discovering," labelling and calculating different "ages" in children. Those new "ages"--from mental to emotional, social, anatomical ages, and more--were understood as either replacing, or meaningfully related to,…

  9. Personal strengths and traumatic experiences among institutionalized children given up at birth (Les Enfants de Duplessis--Duplessis' children): I: Early experiences.

    PubMed

    Perry, J Christopher; Sigal, John J; Boucher, Sophie; Paré, Nikolas; Ouimet, Marie Claude

    2005-12-01

    We examined childhood and early adult strengths and adverse experiences of a group of orphans given up at or near birth and raised in Quebec institutions into early adulthood. A follow-up interview of 81 adults (41 women, 40 men) at a mean age of 59.2 years included retrospective assessments of childhood experiences. Most participants reported multiple early adverse experiences, including, in descending order, unfair rules and excessive punishment, physical abuse, emotional neglect, witnessing violence, verbal abuse, physical neglect, sexual abuse, and serious illness. Adverse experiences were mainly due to lay caretakers, not peers or nuns. Twelve childhood strengths, such as self-protectiveness and athletic talent, were scored at each of four age periods, yielding a median score equivalent to one strength at each period. Over half had significant childhood attachments, but of limited intimacy. Childhood variables correlated with their respective variables in later adulthood. Overall, these older adults reported a high prevalence of adverse or traumatic childhood experiences, counterbalanced by modest levels of individual strengths and attachment relationships. Institutionalization of children--if unavoidable--must build in effective safeguards against adverse experiences.

  10. Personal strengths and traumatic experiences among institutionalized children given up at birth (Les Enfants de Duplessis--Duplessis' children): I: Early experiences.

    PubMed

    Perry, J Christopher; Sigal, John J; Boucher, Sophie; Paré, Nikolas; Ouimet, Marie Claude

    2005-12-01

    We examined childhood and early adult strengths and adverse experiences of a group of orphans given up at or near birth and raised in Quebec institutions into early adulthood. A follow-up interview of 81 adults (41 women, 40 men) at a mean age of 59.2 years included retrospective assessments of childhood experiences. Most participants reported multiple early adverse experiences, including, in descending order, unfair rules and excessive punishment, physical abuse, emotional neglect, witnessing violence, verbal abuse, physical neglect, sexual abuse, and serious illness. Adverse experiences were mainly due to lay caretakers, not peers or nuns. Twelve childhood strengths, such as self-protectiveness and athletic talent, were scored at each of four age periods, yielding a median score equivalent to one strength at each period. Over half had significant childhood attachments, but of limited intimacy. Childhood variables correlated with their respective variables in later adulthood. Overall, these older adults reported a high prevalence of adverse or traumatic childhood experiences, counterbalanced by modest levels of individual strengths and attachment relationships. Institutionalization of children--if unavoidable--must build in effective safeguards against adverse experiences. PMID:16319698

  11. Age-related maintenance of eccentric strength: a study of temperature dependence.

    PubMed

    Power, Geoffrey A; Flaaten, Nordan; Dalton, Brian H; Herzog, Walter

    2016-04-01

    With adult aging, eccentric strength is maintained better than isometric strength leading to a higher ratio of eccentric/isometric force production (ECC/ISO) in older than younger adults. The purpose was to investigate the ECC/ISO during electrical activation of the adductor pollicis during lengthening (20-320° s(-1)) contractions in 24 young (n = 12, ∼24 years) and old (n = 12, ∼72 years) males across muscle temperatures (cold ∼19 °C; normal ∼30 °C; warm ∼35 °C). For isometric force, the old were 20-30 % weaker in the normal and cold conditions (P < 0.05) with no difference for the warm condition compared to young (P > 0.05). Half-relaxation time (HRT) did not differ across age for the normal and warm temperatures (P > 0.05), but it slowed significantly for old in the cold condition compared with young (∼15 %; P < 0.05), as well, there was a 20 and 40 % increase in muscle stiffness for the young and old, respectively. ECC/ISO was 50-60 % greater for the cold condition than the normal and warm conditions. There was no age difference in ECC/ISO across ages for the normal and warm conditions (P > 0.05), but for the cold, the old exhibited a 20-35 % higher ECC/ISO than did the young for velocities above 60° s(-1) (P < 0.05). A contributing factor to the elevated ECC/ISO is an increased proportion of weakly compared to strongly bound crossbridges. These findings highlight the relationship (r = 0.70) between intrinsic muscle contractile speed (HRT) and eccentric strength in old age. PMID:27028894

  12. Shear bond strength of orthodontic brackets to aged resin composite surfaces: effect of surface conditioning.

    PubMed

    Bayram, Mehmet; Yesilyurt, Cemal; Kusgöz, Adem; Ulker, Mustafa; Nur, Metin

    2011-04-01

    The aim of this study was to investigate the effects of surface conditioning protocols on the shear bond strength (SBS) of metal brackets to aged composite resin surfaces in vitro. Ninety composite resin discs, 6 mm in diameter and 2 mm in height, were prepared and treated with an ageing procedure. After ageing, the specimens were randomly assigned to one of the following groups: (1) control with no surface treatment, (2) 38 per cent phosphoric acid gel, (3) 9.6 per cent hydrofluoric acid gel, (4) airborne aluminium trioxide particle abrasion, (5) sodium bicarbonate particle abrasion, and (6) diamond bur. The metal brackets were bonded to composite surfaces by means of an orthodontic adhesive (Transbond XT). All specimens were stored in water for 1 week at 37°C and then thermocycled (1000 cycles, 5-55°C) prior to SBS testing. SBS values and residual adhesive on the composite surface were evaluated. Analysis of variance showed a significant difference (P = 0.000) between the groups. Group 6 had the highest mean SBS (10.61 MPa), followed by group 4 (10.29 MPa). The results of this study suggest that a clinically acceptable bond strength can be achieved by surface conditioning of aged resin composite via the application of hydrofluoric acid, aluminium trioxide particle abrasion, sodium bicarbonate particle abrasion, or a diamond bur. PMID:20660131

  13. Fish consumption and early atherosclerosis in middle-aged men.

    PubMed

    Nakamura, Yasuyuki; Ueno, Yoshiki; Tamaki, Shinji; Kadowaki, Takashi; Okamura, Tomonori; Kita, Yoshikuni; Miyamatsu, Naomi; Sekikawa, Akira; Takamiya, Tomoko; El-Saed, Aiman; Sutton-Tyrrell, Kim; Ueshima, Hirotsugu

    2007-08-01

    To investigate the association between fish consumption and early atherosclerosis, we analyzed the relationship between fish consumption and average intima-media thickness (AveIMT) by carotid ultrasound in middle-aged Japanese men. Participants were 250 randomly selected, community-based Japanese men aged 40 to 49 years without a prior history of cardiovascular disease. AveIMT was calculated from the mean of 1-cm lengths of both the right and the left carotid arteries at 8 locations. A lifestyle survey was carried out using a self-administered questionnaire including the frequency of fish intake. There were 147 men in the fewer than 4 times per week fish consumption group and 103 men in the 4 or more times per week group. The mean AveIMT was significantly higher in the low fish consumption group than in the high fish consumption group (0.623+/-0.068 vs 0.605+/-0.065 mm, P=.03). After adjustment for age, waist circumference, pack-years of smoking, alcohol consumption, diabetes, and lipid-lowering medications, the significant difference in the AveIMT between the 2 groups remained. However, after further adjustment for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and C-reactive protein in the model, the significant difference disappeared. Fish consumption may be protective against early atherosclerosis in middle-aged men, probably through its beneficial effects on inflammation.

  14. Age of acquisition in sport: starting early matters.

    PubMed

    Hernandez, Arturo E; Mattarella-Micke, Andrew; Redding, Richard W T; Woods, Elizabeth A; Beilock, Sian

    2011-01-01

    Although the age at which a skill is learned (age of acquisition [AoA]) is one of the most studied predictors of success in domains ranging from language to music, very little work has focused on this factor in sports. In order to uncover how the age at which a skill is learned relates to how athletes cognitively represent that skill, we asked a group of skilled golfers who learned to play golf before (early learners) or after (late learners) the age of 10 to take a series of putts on an indoor putting green. Golfers putted in isolation (single-task condition), while monitoring a stream of words presented over a loudspeaker (dual-task condition), or while being instructed to attend to specific aspects of their golf swing (skill-focused condition). Early and late learners putted equally well in the single-task and dual-task conditions. However, in the skill-focused condition, golfers who learned earlier performed worse than those who learned later. The results are consistent with the notion that AoA influences the manner in which sports, like other domains such as language and music, are represented in memory. PMID:21977688

  15. Age- and sex-related regional compressive strength characteristics of human lumbar vertebrae in osteoporosis

    PubMed Central

    Kurutz, Márta; Donáth, Judit; Gálos, Miklós; Varga, Péter; Fornet, Béla

    2008-01-01

    Objective To obtain the compressive load bearing and energy absorption capacity of lumbar vertebrae of osteoporotic elderly for the everyday medical praxis in terms of the simple diagnostic data, like computed tomography (CT), densitometry, age, and sex. Methods Compressive test of 54 osteoporotic cadaver vertebrae L1 and L2, 16 males and 38 females (age range 43–93, mean age 71.6 ± 13.3 years, mean bone mineral density (BMD) 0.377 ± 0.089 g/cm2, mean T-score −5.57 ± 0.79, Z-score −4.05 ± 0.77) was investigated. Based on the load-displacement diagrams and the measured geometrical parameters of vertebral bodies, proportional, ultimate and yield stresses and strains, Young’s modulus, ductility and energy absorption capacity were determined. Three vertebral regions were distinguished: superior, central and inferior regions, but certain parameters were calculated for the upper/ lower intermediate layers, as well. Cross-sectional areas, and certain bone tissue parameters were determined by image analysis of CT pictures of vertebrae. Sex- and age-related decline functions and trends of strength characteristics were determined. Results Size-corrected failure load was 15%–25% smaller in women, proportional and ultimate stresses were about 30%–35% smaller for women in any region, and 20%–25% higher in central regions for both sexes. Young’s moduli were about 30% smaller in women in any region, and 20%–25% smaller in the central region for both sexes. Small strains were higher in males, large strains were higher in females, namely, proportional strains were about 25% larger in men, yield and ultimate strains were quasi equal for sexes, break strains were 10% higher in women. Ultimate energy absorption capacity was 10%–20% higher in men; the final ductile energy absorption capacity was quasi equal for sexes in all levels. Age-dependence was stronger for men, mainly in central regions (ultimate load, male: r = −0.66, p < 0.01, female: r = −0.52, p

  16. Effects of negative ageing on deformation and strength response of geomaterials

    NASA Astrophysics Data System (ADS)

    Aziz, M.; Towhata, I.; Yamada, S.; Qureshi, M. U.; Kawano, K.

    2009-04-01

    Negative ageing or decay of grains with time is often ignored in conventional geotechnical investigations. Geology is always vital in such a scenario but the micro-scale geotechnical point of concern is the time-dependent loss of strength and deformation characteristics. This paper presents unique data from torsional shear tests on crushed soft rocks from Yokosuka, Japan and 2005-Kashmir earthquake hit areas of Pakistan. Material being sensitive to disintegrate by water-action allowed to simulate the long-term stress-strain and volume change response under saturated conditions whereas dry tests on similar soil represent initial intact response of the material. Negative ageing is manipulated by an enormous decrease in shear strength parameters, changes in grain size curve and increase in volumetric compression. It is concluded that for long-term hazard evaluation of various geotechnical structures, the effects of loss of strength due to decay of grains with time should be incorporated in conventional analysis and design models.

  17. [COMPREHENSIVE ASSESSMENT OF HEALTH IN BABIES OF EARLY PRESCHOOL AGE].

    PubMed

    Denisov, A P; Semenova, N V; Kun, O A; Denisova, O A

    2015-01-01

    Health of the children's population is one of the most important components of safety of the country. The incidence level in children of early age reflects an interaction of economic, ecological, social and hygienic and medico-organizational factors in society. The issue of the paper is the comprehensive assessment of health of children of the first three years of life upon indices of the morbidity rate, physical development, interrelation of given indices with the structure of the family and their social status. Indices of the physical development of boys in the all age groups exceeded the corresponding indices in girls (p < 0.05). There was also statistically significant and augmentation of indices of body weights of children along with the age (p < 0.05). The highest morbidity rate in children was established in the first year of life, the minimal one--in the third year. In the all age groups diseases of respiratory organs prevailed, at this their proportion in the total amount of diseases in the third year of life considerably exceeded the same in first and second years of life. The highest incidences of children took place in the families formed by juvenile and lonely women. Diseases of digestive organs in the second and third years of life in children from juvenile and lonely mothers were considerably enlarged on frequency (by 1,4-1,7 times), infectious and parasitic diseases (by 1,1-1,7 times) in comparison with children from full families. In the all studied types offamilies and age groups the state of health of children was worse, than in full families. There was substantiated the development of the multilevel system for the prophylaxis of losses of health in children at early preschool age. PMID:26856178

  18. Supporting Early Childhood Preservice Teachers in Their Work with Children and Families with Complex Needs: A Strengths Approach

    ERIC Educational Resources Information Center

    Fenton, Angela; McFarland-Piazza, Laura

    2014-01-01

    This article explores the potential of tailoring the inherent principles of the Strengths Approach (McCashen, 2005) for preparing early childhood educators to work with children and families with complex needs. The term "Strengths Approach" (capitalized) is presented in the article as the name of a specific approach developed by St.…

  19. Effect of aging on tear strength and cytotoxicity of soft denture lining materials; in vitro

    PubMed Central

    Landayan, Jordi Izzard Andaya; Manaloto, Adrian Carlos Francisco; Shin, Sang-Wan

    2014-01-01

    PURPOSE The aim of this in vitro study was to evaluate the effect of aging on the tear strength and cytotoxicity of four soft denture lining materials. MATERIALS AND METHODS Four commonly used soft denture lining materials, (Coe-Comfort™ GC America Inc., Alsip, IL, USA; Coe-Soft™ GC America Inc., Alsip, IL, USA; Visco-gel Dentsply Caulk Milford, DE, USA; and Sofreliner Tough M Tokuyama Dental Corporation Tokyo, Japan) were selected. Sixty trouser-leg designed specimens per lining material were fabricated using a stainless steel mold for tear strength testing. The specimens were divided into non-thermocycling and 1000-, and 3000- thermocycling groups. For the cytotoxicity test, twenty-four disk shaped specimens per material were fabricated using a stainless steel mold. The specimens were soaked in normal saline solution for 24 h, 48 h and 72 h. Cytotoxicity was measured by XTT assay in L929 mouse fibroblasts. Data were analyzed by two way analysis of variance and Dunnett's test (P<.05). RESULTS Before thermocycling, Sofreliner Tough M (10.36 ± 1.00 N) had the highest tear strength value while Coe-Comfort™ (0.46 ± 0.10 N) had the lowest. After 3000 cycles, Sofreliner Tough M (9.65 ± 1.66 N) presented the highest value and Coe-Comfort™ (0.42 ± 0.08 N) the lowest. Sofreliner Tough M, in all incubation periods was the least toxic with significant differences compared to all other materials (P<.05). Coe-Comfort™, Coe-Soft™, and Sofreliner Tough M did not show any significant differences within their material group for all incubation periods. CONCLUSION This in vitro study revealed that aging can affect both the tear strength and cytotoxicity of soft denture materials depending on the composition. PMID:24843396

  20. Structure and properties during aging of an ultra-high strength Al-Cu-Li-Ag-Mg alloy

    NASA Technical Reports Server (NTRS)

    Gayle, Frank W.; Heubaum, Frank H.; Pickens, Joseph R.

    1990-01-01

    The structure and properties of the strengthening phases formed during aging in an Al-Cu-Li-Ag-Mg alloy (Weldalite 049) were elulcidated, by following the development of the microstructure by means of TEM. The results of observations showed that the Weldalite 049 alloy has a series of unusual and technologically useful combinations of mechanical properties in different aging conditions, such as natural aging without prior cold work to produce high strengths, a reversion temper of lower yield strength and unusually high ductility, a room temperature reaging of the reversion temper eventually leading to the original T4 hardness, and ultrahigh-strength T6 properties.

  1. Early-age monitoring of cement structures using FBG sensors

    NASA Astrophysics Data System (ADS)

    Wang, Chuan; Zhou, Zhi; Zhang, Zhichun; Ou, Jinping

    2006-03-01

    With more and more broad applications of the cement-based structures such as neat cement paste, cement mortar and concrete in civil engineering, people hope to find out what their performances should like. The in-service performances of cement-based structures are highly affected by their hardening process during the early-age. But it is still a big problem for traditional sensors to be used to monitor the early curing of cement-based structures due to such disadvantages as difficulties to install sensors inside the concrete, limited measuring points, poor durability and interference of electromagnetic wave and so on. In this paper, according to the sensing properties of the Fiber Bragg Grating sensors and self-characters of the cement-based structures, we have successfully finished measuring and monitoring the early-age inner-strain and temperature changes of the neat cement paste, concrete with and without restrictions, mass concrete structures and negative concrete, respectively. Three types of FBG-based sensors have been developed to monitor the cement-based structures. Besides, the installation techniques and the embedding requirements of FBG sensors in cement-based structures are also discussed. Moreover, such kind of technique has been used in practical structure, 3rd Nanjing Yangtze Bridge, and the results show that FBG sensors are well proper for measuring and monitoring the temperature and strain changes including self-shrinkage, dry shrinkage, plastic shrinkage, temperature expansion, frost heaving and so on inside different cement-based structures. This technique provides us a new useful measuring method on early curing monitoring of cement-based structures and greater understanding of details of their hardening process.

  2. Computational Thermomechanical Modelling of Early-Age Silicate Composites

    NASA Astrophysics Data System (ADS)

    Vala, J.; Št'astník, S.; Kozák, V.

    2009-09-01

    Strains and stresses in early-age silicate composites, widely used in civil engineering, especially in fresh concrete mixtures, in addition to those caused by exterior mechanical loads, are results of complicated non-deterministic physical and chemical processes. Their numerical prediction at the macro-scale level requires the non-trivial physical analysis based on the thermodynamic principles, making use of micro-structural information from both theoretical and experimental research. The paper introduces a computational model, based on a nonlinear system of macroscopic equations of evolution, supplied with certain effective material characteristics, coming from the micro-scale analysis, and sketches the algorithm for its numerical analysis.

  3. Comprehensive analyses of how tubule occlusion and advanced glycation end-products diminish strength of aged dentin

    PubMed Central

    Shinno, Yuko; Ishimoto, Takuya; Saito, Mitsuru; Uemura, Reo; Arino, Masumi; Marumo, Keishi; Nakano, Takayoshi; Hayashi, Mikako

    2016-01-01

    In clinical dentistry, since fracture is a major cause of tooth loss, better understanding of mechanical properties of teeth structures is important. Dentin, the major hard tissue of teeth, has similar composition to bone. In this study, we investigated the mechanical properties of human dentin not only in terms of mineral density but also using structural and quality parameters as recently accepted in evaluating bone strength. Aged crown and root dentin (age ≥ 40) exhibited significantly lower flexural strength and toughness than young dentin (age < 40). Aged dentin, in which the dentinal tubules were occluded with calcified material, recorded the highest mineral density; but showed significantly lower flexural strength than young dentin. Dentin with strong alignment of the c-axis in hydroxyapatite exhibited high fracture strength, possibly because the aligned apatite along the collagen fibrils may reinforce the intertubular dentin. Aged dentin, showing a high advanced glycation end-products (AGEs) level in its collagen, recorded low flexural strength. We first comprehensively identified significant factors, which affected the inferior mechanical properties of aged dentin. The low mechanical strength of aged dentin is caused by the high mineral density resulting from occlusion of dentinal tubules and accumulation of AGEs in dentin collagen. PMID:26797297

  4. The effects of strength training and raloxifene on bone health in aging ovariectomized rats.

    PubMed

    Stringhetta-Garcia, Camila Tami; Singulani, Monique Patrício; Santos, Leandro Figueiredo; Louzada, Mário Jefferson Quirino; Nakamune, Ana Cláudia Stevanato; Chaves-Neto, Antonio Hernandes; Rossi, Ana Cláudia; Ervolino, Edilson; Dornelles, Rita Cássia Menegati

    2016-04-01

    The aim of this study was to investigate the effects of strength training (ST) and raloxifene (Ral), alone or in combination, on the prevention of bone loss in an aging estrogen-deficient rat model. Aging Wistar female rats were ovariectomized at 14months and allocated to four groups: (1) non-trained and treated with vehicle, NT-Veh; (2) strength training and treated with vehicle, ST-Veh; (3) non-trained and treated with raloxifene, NT-Ral; and (4) strength training and treated with raloxifene, ST-Ral. ST was performed on a ladder three times per week and Ral was administered daily by gavage (1mg/kg/day), both for 120days. Areal bone mineral density (aBMD), strength, microarchitecture, and biomarkers (osteocalcin, OCN; osteoprotegerin, OPG; and tartrate-resistant acid phosphatase, TRAP) were assessed. Immunohistochemistry was performed for runt-related transcription factor 2 (RUNX2), osterix (OSX), OCN, OPG, TRAP, and receptor activator of nuclear factor kappa-B ligand (RANKL). The rats that performed ST (ST-Veh) or were treated with Ral (NT-Ral) showed significant improvements in aBMD (p=0.001 and 0.004), bone strength (p=0.001), and bone microarchitecture, such as BV/TV (%) (p=0.001), BS/TV (mm(2)/mm(3)) (p=0.023 and 0.002), Conn.Dn (1/mm(3)) (p=0.001), Tb.N (1/mm) (p=0.012 and 0.011), Tb.Th (1/mm) (p=0.001), SMI (p=0.001 and 0.002), Tb.Sp (p=0.001), and DA (p=0.002 and 0.007); there was also a significant decrease in plasma levels of OCN (p=0.001 and 0.002) and OPG (p=0.003 and 0.014), compared with animals in the NT-Veh group. Ral, with or without ST, promoted an increased immunolabeling pattern for RUNX2 (p=0.0105 and p=0.0006) and OSX (p=0.0105), but a reduced immunolabeling pattern for TRAP (p=0.0056) and RANKL (p=0.033 and 0.004). ST increased the immunolabeling pattern for RUNX2 (p=0.0105), and association with Ral resulted in an increased immunolabeling pattern for OPG (p=0.0034) and OCN (p=0.0024). In summary, ST and Ral administration in aged, estrogen

  5. Known for My Strengths: Positive Traits of Transition-Age Youth With Intellectual Disability and/or Autism

    ERIC Educational Resources Information Center

    Carter, Erik W.; Boehm, Thomas L.; Biggs, Elizabeth E.; Annandale, Naomi H.; Taylor, Courtney E.; Loock, Aimee K.; Liu, Rosemary Y.

    2015-01-01

    Can young people with intellectual and developmental disabilities be known for their strengths? This mixed-method study explored the strengths of 427 youth and young adults with intellectual disability and/or autism (ages 13-21) from the vantage point of their parents. Using the Assessment Scale for Positive Character Traits-Developmental…

  6. Effects of age and sex on neuromuscular-mechanical determinants of muscle strength.

    PubMed

    Wu, Rui; Delahunt, Eamonn; Ditroilo, Massimiliano; Lowery, Madeleine; De Vito, Giuseppe

    2016-06-01

    The aim of this study was to concurrently assess the effect of age on neuromuscular and mechanical properties in 24 young (23.6 ± 3.7 years) and 20 older (66.5 ± 3.8 years) healthy males and females. Maximal strength of knee extensors (KE) and flexors (KF), contractile rate of torque development (RTD) and neural activation of agonist-antagonist muscles (surface EMG) were examined during maximal voluntary isometric contraction (MVIC). Tissue stiffness (i.e. musculo-articular stiffness (MAS) and muscle stiffness (MS)) was examined via the free-oscillation technique, whereas muscle architecture (MA) of the vastus lateralis and subcutaneous fat were measured by ultrasonography. Males exhibited a greater age-related decline for KE (47.4 %) and KF (53.1 %) MVIC, and RTD (60.4 %) when compared to females (32.9, 42.6 and 34.0 %, respectively). Neural activation of agonist muscles during KE MVIC falls markedly with ageing; however, no age and sex effects were observed in the antagonist co-activation. MAS and MS were lower in elderly compared with young participants and in females compared with males. Regarding MA, main effects for age (young 23.0 ± 3.3 vs older 19.5 ± 2.0 mm) and sex (males 22.4 ± 3.5 vs females 20.4 ± 2.7 mm) were detected in muscle thickness. For fascicle length, there was an effect of age (young 104.6 ± 8.8 vs older 89.8 ± 10.5 mm), while for pennation angle, there was an effect of sex (males 13.3 ± 2.4 vs females 11.5 ± 1.7°). These findings suggest that both neuromuscular and mechanical declines are important contributors to the age-related loss of muscle strength/function but with some peculiar sex-related differences. PMID:27189591

  7. Age and response bias: evidence from the strength-based mirror effect.

    PubMed

    Criss, Amy H; Aue, William; Kılıç, Aslı

    2014-10-01

    Performance in episodic memory is determined both by accurate retrieval from memory and by decision processes. A substantial body of literature suggests slightly poorer episodic memory accuracy for older than younger adults; however, age-related changes in the decision mechanisms in memory have received much less attention. Response bias, the willingness to endorse an item as remembered, is an important decision factor that contributes to episodic memory performance, and therefore understanding age-related changes in response bias is critical to theoretical development. We manipulate list strength in order to investigate two aspects of response bias. First, we evaluate whether criterion placement in episodic memory differs for older and younger adults. Second, we ask whether older adults have the same degree of flexibility to adjust the criterion in response to task demands as younger adults. Participants were tested on weakly and strongly encoded lists where word frequency (Experiment 1) or similarity between targets and foils (Experiment 2) was manipulated. Both older and younger adults had higher hit rates and lower false-alarm rates for strong lists than for weak lists (i.e., a strength-based mirror effect). Older adults were more conservative (less likely to endorse an item as studied) than younger adults, and we found no evidence that older and younger adults differ in their ability to flexibly adjust their criterion based on the demands of the task.

  8. Slab Deformation in the Mantle Transition Zone: The Effect of Plate Age and Strength Evolution

    NASA Astrophysics Data System (ADS)

    Goes, S. D. B.; Garel, F.; Davies, R.; Davies, J. H.; Kramer, S. C.; Wilson, C. R.

    2014-12-01

    The deformation encountered by subducted tectonic plates at the base of the upper mantle influences Earth's thermal, chemical, and tectonic evolution. Yet the mechanisms responsible for the wide range of imaged slab morphologies, either stagnating in the transition zone or penetrating into the lower mantle, remain debated. We use 2-D thermo-mechanical models of a two-plate subduction system, modeled with the finite-element, adaptive-mesh code Fluidity. We implement a temperature- and stress-dependent rheology, and viscosity increases 30-fold from upper to lower mantle. Trench position evolves freely in response to plate dynamics. Such an approach self-consistently captures feedbacks between temperature, density, flow, strength and deformation. Our results indicate that key controls on subduction dynamics and slab morphology are: (i) the evolution of slab strength; and (ii) the slab's ability to induce trench motion. We build a regime diagram that distinguishes four subduction styles: (1) a "vertical folding" mode with stationary trench; (2) young slabs that are "horizontally deflected" along the 660-km deep viscosity jump ; (3) an inclined slab morphology, resulting from strong trench retreat (old slabs and thinner overriding plates); and (4) a two-stage mode, displaying bent (rolled-over) slabs at the end of upper-mantle descent, that subsequently unbend and achieve inclined morphologies, with late trench retreat (strong overriding plates). We find that the interplay between trench motion and slab deformation at depth dictates the subduction style, both being controlled by slab strength. We show that all seismically observed slab morphologies in the transition zone can arise just by changing the subducting-plate ages. However, to understand present-day slab morphologies, we have to analyse subduction history rather than just current age at the trench.

  9. NORMATIVE VALUES OF ECCENTRIC HIP ABDUCTION STRENGTH IN NOVICE RUNNERS: AN EQUATION ADJUSTING FOR AGE AND GENDER

    PubMed Central

    Pedersen, M.B.; Kastrup, K.; Lønbro, S.; Jacobsen, J.S.; Thorborg, K.; Nielsen, R.O.; Rasmussen, S.

    2014-01-01

    Purpose: Low eccentric strength of the hip abductors, might increase the risk of patellofemoral pain syndrome and iliotibial band syndrome in runners. No normative values for maximal eccentric hip abduction strength have been established. Therefore the purpose of this study was to establish normative values of maximal eccentric hip abduction strength in novice runners. Methods: Novice healthy runners (n = 831) were recruited through advertisements at a hospital and a university. Maximal eccentric hip abduction strength was measured with a hand–held dynamometer. The demographic variables associated with maximal eccentric hip abduction strength from a univariate analysis were included in a multivariate linear regression model. Based on the results from the regression model, a regression equation for normative hip abduction strength is presented. Results: A significant difference in maximal eccentric hip abduction strength was found between males and females: 1.62 ± 0.38 Nm/kg (SD) for males versus 1.41 ± 0.33 Nm/kg (SD) for females (p < 0.001). Age was associated with maximal eccentric hip abduction strength: per one year increase in age a ‐0.0045 ± 0.0013 Nm/kg (SD) decrease in strength was found, p < 0.001. Normative values were identified using a regression equation adjusting for age and gender. Based on this, the equation to calculate normative values for relative eccentric hip abduction strength became: (1.600 + (age * ‐0.005) + (gender (1 = male / 0 = female) * 0.215) ± 1 or 2 * 0.354) Nm/kg. Conclusion: Normative values for maximal eccentric hip abduction strength in novice runners can be calculated by taking into account the differences in strength across genders and the decline in strength that occurs with increasing age. Age and gender were associated with maximal eccentric hip abduction strength in novice runners, and these variables should be taken into account when evaluating eccentric hip abduction strength in this group of athletes. Level of

  10. Ageing influence in the evolution of strength and muscle mass in women with fibromyalgia: the al-Ándalus project.

    PubMed

    Latorre-Román, Pedro Ángel; Segura-Jiménez, Víctor; Aparicio, Virginia A; Santos E Campos, María Aparecida; García-Pinillos, Felipe; Herrador-Colmenero, Manuel; Álvarez-Gallardo, Inmaculada C; Delgado-Fernández, Manuel

    2015-07-01

    Fibromyalgia is associated with physical disabilities in daily activities. Moreover, patients with fibromyalgia present similar levels of functional capacity and physical condition than elderly people. The aim of this study was to analyse the evolution of strength and muscle mass in women with fibromyalgia along ageing. A total sample of 492 fibromyalgia patients and 279 healthy control women were included in the study. Participants in each group were further divided into four age subgroups: subgroup 1: 30-39 years old, subgroup 2: 40-49 years old, subgroup 3: 50-59 years old and subgroup 4: 60-69 years old. Standardized field-based fitness tests were used to assess muscle strength (30-s chair stand, handgrip strength and arm curl tests). Fibromyalgia patients did not show impairment on muscle mass along ageing, without values of skeletal muscle mass index below 6.76 kg/m(2) in any group. However, in all variables of muscle strength, the fibromyalgia group showed less strength than the healthy group (p < 0.05) for all age groups. As expected, handgrip strength test showed differences along ageing only in the fibromyalgia group (p < 0.001). Age was inversely associated with skeletal muscle mass (r = -0.155, p < 0.01) and handgrip strength (r = -0.230, p < 0.001) in the FM group. Women with fibromyalgia showed a reduction in muscle strength along ageing process, with significantly lower scores than healthy women for each age group, representing a risk of dynapenia.

  11. The Association of Levels of and Decline in Grip Strength in Old Age with Trajectories of Life Course Occupational Position

    PubMed Central

    Fritzell, Johan; Hoffmann, Rasmus

    2016-01-01

    Background The study of the influence of life course occupational position (OP) on health in old age demands analysis of time patterns in both OP and health. We study associations between life course time patterns of OP and decline in grip strength in old age. Methods We analyze 5 waves from the Survey of Health Ageing and Retirement in Europe (n = 5108, ages 65–90). We use a pattern-mixture latent growth model to predict the level and decline in grip strength in old age by trajectory of life course OP. We extend and generalize the structured regression approach to establish the explanatory power of different life course models for both the level and decline of grip strength. Results Grip strength declined linearly by 0.70 kg (95% CI -0.74;-0.66) for men and 0.42 kg (95% CI -0.45;-0.39) for women per year. The level of men’s grip strength can best be explained by a critical period during midlife, with those exposed to low OP during this period having 1.67 kg (95% CI -2.33;-1.00) less grip strength. These differences remain constant over age. For women, no association between OP and levels of or decline in grip strength was found. Conclusions Men’s OP in midlife seems to be a critical period for the level of grip strength in old age. Inequalities remain constant over age. The integration of the structured regression approach and latent growth modelling offers new possibilities for life course epidemiology. PMID:27232696

  12. Live strong and prosper: the importance of skeletal muscle strength for healthy ageing.

    PubMed

    McLeod, Michael; Breen, Leigh; Hamilton, D Lee; Philp, Andrew

    2016-06-01

    Due to improved health care, diet and infrastructure in developed countries, since 1840 life expectancy has increased by approximately 2 years per decade. Accordingly, by 2050, a quarter of Europe's population will be over 65 years, representing a 10 % rise in half a century. With this rapid rise comes an increased prevalence of diseases of ageing and associated healthcare expenditure. To address the health consequences of global ageing, research in model systems (worms, flies and mice) has indicated that reducing the rate of organ growth, via reductions in protein synthetic rates, has multi-organ health benefits that collectively lead to improvements in lifespan. In contrast, human pre-clinical, clinical and large cohort prospective studies demonstrate that ageing leads to anabolic (i.e. growth) impairments in skeletal muscle, which in turn leads to reductions in muscle mass and strength, factors directly associated with mortality rates in the elderly. As such, increasing muscle protein synthesis via exercise or protein-based nutrition maintains a strong, healthy muscle mass, which in turn leads to improved health, independence and functionality. The aim of this review is to critique current literature relating to the maintenance of muscle mass across lifespan and discuss whether maintaining or reducing protein synthesis is the most logical approach to support musculoskeletal function and by extension healthy human ageing. PMID:26791164

  13. Long-Term Isothermal Aging Effects on Carbon Fabric-Reinforced PMR-15 Composites: Compression Strength

    NASA Technical Reports Server (NTRS)

    Bowles, Kenneth J.; Roberts, Gary D.; Kamvouris, John E.

    1996-01-01

    A study was conducted to determine the effects of long-term isothermal thermo-oxidative aging on the compressive properties of T-650-35 fabric reinforced PMR-15 composites. The temperatures that were studied were 204, 260, 288, 316, and 343 C. Specimens of different geometries were evaluated. Cut edge-to-surface ratios of 0.03 to 0.89 were fabricated and aged. Aging times extended to a period in excess of 15,000 hours for the lower temperature runs. The unaged and aged specimens were tested in compression in accordance with ASTM D-695. Both thin and thick (plasma) specimens were tested. Three specimens were tested at each time/temperature/geometry condition. The failure modes appeared to be initiated by fiber kinking with longitudinal, interlaminar splitting. In general, it appears that the thermo-oxidative degradation of the compression strength of the composite material may occur by both thermal (time-dependent) and oxidative (weight-loss) mechanisms. Both mechanisms appear to be specimen-thickness dependent.

  14. Live strong and prosper: the importance of skeletal muscle strength for healthy ageing.

    PubMed

    McLeod, Michael; Breen, Leigh; Hamilton, D Lee; Philp, Andrew

    2016-06-01

    Due to improved health care, diet and infrastructure in developed countries, since 1840 life expectancy has increased by approximately 2 years per decade. Accordingly, by 2050, a quarter of Europe's population will be over 65 years, representing a 10 % rise in half a century. With this rapid rise comes an increased prevalence of diseases of ageing and associated healthcare expenditure. To address the health consequences of global ageing, research in model systems (worms, flies and mice) has indicated that reducing the rate of organ growth, via reductions in protein synthetic rates, has multi-organ health benefits that collectively lead to improvements in lifespan. In contrast, human pre-clinical, clinical and large cohort prospective studies demonstrate that ageing leads to anabolic (i.e. growth) impairments in skeletal muscle, which in turn leads to reductions in muscle mass and strength, factors directly associated with mortality rates in the elderly. As such, increasing muscle protein synthesis via exercise or protein-based nutrition maintains a strong, healthy muscle mass, which in turn leads to improved health, independence and functionality. The aim of this review is to critique current literature relating to the maintenance of muscle mass across lifespan and discuss whether maintaining or reducing protein synthesis is the most logical approach to support musculoskeletal function and by extension healthy human ageing.

  15. Cross-education of strength and skill: an old idea with applications in the aging nervous system.

    PubMed

    Barss, Trevor S; Pearcey, Gregory E P; Zehr, E Paul

    2016-03-01

    Edward Wheeler Scripture's 1894 work out of the Yale Psychological Laboratory has been influential in identifying the nervous system's contribution to the bilateral improvements that are seen with unilateral strength and skill training. Scripture coined the term "cross-education" to describe this improvement in the untrained contralateral limb. While physiological changes accompany aging that may negatively affect the performance of physical tasks, far too much credit has been given to the natural aging process rather than the effects of inactivity. Emerging evidence indicates strength or skill training interventions induce significant neuroplasticity in an aging population. The model of unilateral training provides a unique approach in which to elicit such plasticity. This brief review highlights the innate ability of the nervous system to adapt to unilateral strength and skill training interventions, regardless of age, and provides a novel perspective on the robust plastic ability of the aging nervous system.

  16. Cross-education of strength and skill: an old idea with applications in the aging nervous system

    PubMed Central

    Barss, Trevor S.; Pearcey, Gregory E.P.; Zehr, E. Paul

    2016-01-01

    Edward Wheeler Scripture’s 1894 work out of the Yale Psychological Laboratory has been influential in identifying the nervous system’s contribution to the bilateral improvements that are seen with unilateral strength and skill training. Scripture coined the term “cross-education” to describe this improvement in the untrained contralateral limb. While physiological changes accompany aging that may negatively affect the performance of physical tasks, far too much credit has been given to the natural aging process rather than the effects of inactivity. Emerging evidence indicates strength or skill training interventions induce significant neuroplasticity in an aging population. The model of unilateral training provides a unique approach in which to elicit such plasticity. This brief review highlights the innate ability of the nervous system to adapt to unilateral strength and skill training interventions, regardless of age, and provides a novel perspective on the robust plastic ability of the aging nervous system. PMID:27505019

  17. Cross-education of strength and skill: an old idea with applications in the aging nervous system.

    PubMed

    Barss, Trevor S; Pearcey, Gregory E P; Zehr, E Paul

    2016-03-01

    Edward Wheeler Scripture's 1894 work out of the Yale Psychological Laboratory has been influential in identifying the nervous system's contribution to the bilateral improvements that are seen with unilateral strength and skill training. Scripture coined the term "cross-education" to describe this improvement in the untrained contralateral limb. While physiological changes accompany aging that may negatively affect the performance of physical tasks, far too much credit has been given to the natural aging process rather than the effects of inactivity. Emerging evidence indicates strength or skill training interventions induce significant neuroplasticity in an aging population. The model of unilateral training provides a unique approach in which to elicit such plasticity. This brief review highlights the innate ability of the nervous system to adapt to unilateral strength and skill training interventions, regardless of age, and provides a novel perspective on the robust plastic ability of the aging nervous system. PMID:27505019

  18. Association between floating toe and toe grip strength in school age children: a cross-sectional study

    PubMed Central

    Tasaka, Seishiro; Matsubara, Keisuke; Nishiguchi, Shu; Fukutani, Naoto; Tashiro, Yuto; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Matsushita, Tomofumi; Fukumoto, Takahiko; Aoyama, Tomoki

    2016-01-01

    [Purpose] This study investigated the association between floating toe and toe grip strength. [Subjects and Methods] A total of 635 Japanese children aged 9–11 years participated in this study. Floating toe was evaluated using footprint images, while toe grip strength was measured using a toe grip dynamometer. All 1,270 feet were classified into a floating toe group and a normal toe group according to visual evaluation of the footprint images. Intergroup differences in toe grip strength were analyzed using the unpaired t-test and logistic regression analysis adjusted for age, gender, and Rohrer Index. [Results] There were 512 feet (40.3%) in the floating toe group. Mean toe grip strength of the feet with floating toe was significantly lower than that of normal feet (floating toe group, 12.9 ± 3.7 kg; normal toe group, 13.6 ± 4.1 kg). In addition, lower toe grip strength was associated with floating toe on logistic regression analysis after adjustment for age, gender, and Rohrer Index (odds ratio, 0.954; 95% confidence interval, 0.925–0.984). [Conclusion] This study revealed that lower toe grip strength was significantly associated with floating toe. Therefore, increasing toe grip strength may play a role in preventing floating toe in school age children.

  19. Association between floating toe and toe grip strength in school age children: a cross-sectional study

    PubMed Central

    Tasaka, Seishiro; Matsubara, Keisuke; Nishiguchi, Shu; Fukutani, Naoto; Tashiro, Yuto; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Matsushita, Tomofumi; Fukumoto, Takahiko; Aoyama, Tomoki

    2016-01-01

    [Purpose] This study investigated the association between floating toe and toe grip strength. [Subjects and Methods] A total of 635 Japanese children aged 9–11 years participated in this study. Floating toe was evaluated using footprint images, while toe grip strength was measured using a toe grip dynamometer. All 1,270 feet were classified into a floating toe group and a normal toe group according to visual evaluation of the footprint images. Intergroup differences in toe grip strength were analyzed using the unpaired t-test and logistic regression analysis adjusted for age, gender, and Rohrer Index. [Results] There were 512 feet (40.3%) in the floating toe group. Mean toe grip strength of the feet with floating toe was significantly lower than that of normal feet (floating toe group, 12.9 ± 3.7 kg; normal toe group, 13.6 ± 4.1 kg). In addition, lower toe grip strength was associated with floating toe on logistic regression analysis after adjustment for age, gender, and Rohrer Index (odds ratio, 0.954; 95% confidence interval, 0.925–0.984). [Conclusion] This study revealed that lower toe grip strength was significantly associated with floating toe. Therefore, increasing toe grip strength may play a role in preventing floating toe in school age children. PMID:27630423

  20. Association between floating toe and toe grip strength in school age children: a cross-sectional study.

    PubMed

    Tasaka, Seishiro; Matsubara, Keisuke; Nishiguchi, Shu; Fukutani, Naoto; Tashiro, Yuto; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Matsushita, Tomofumi; Fukumoto, Takahiko; Aoyama, Tomoki

    2016-08-01

    [Purpose] This study investigated the association between floating toe and toe grip strength. [Subjects and Methods] A total of 635 Japanese children aged 9-11 years participated in this study. Floating toe was evaluated using footprint images, while toe grip strength was measured using a toe grip dynamometer. All 1,270 feet were classified into a floating toe group and a normal toe group according to visual evaluation of the footprint images. Intergroup differences in toe grip strength were analyzed using the unpaired t-test and logistic regression analysis adjusted for age, gender, and Rohrer Index. [Results] There were 512 feet (40.3%) in the floating toe group. Mean toe grip strength of the feet with floating toe was significantly lower than that of normal feet (floating toe group, 12.9 ± 3.7 kg; normal toe group, 13.6 ± 4.1 kg). In addition, lower toe grip strength was associated with floating toe on logistic regression analysis after adjustment for age, gender, and Rohrer Index (odds ratio, 0.954; 95% confidence interval, 0.925-0.984). [Conclusion] This study revealed that lower toe grip strength was significantly associated with floating toe. Therefore, increasing toe grip strength may play a role in preventing floating toe in school age children. PMID:27630423

  1. Mind the gap: the distributional effects of raising the early eligibility age and full retirement age.

    PubMed

    Olsen, Anya

    2012-01-01

    Policymakers have proposed increases to the early eligibility age (EEA) and/or full retirement age (FRA) to address increasing life expectancy and Social Security solvency issues. This analysis uses the Social Security Administration's Modeling Income in the Near Term, version 6 (MINT6) model to compare three retirement-age increases suggested by the Social Security Advisory Board: increase the gap between the EEA and FRA by raising only the FRA, increase both the EEA and FRA to maintain a 4-year gap between them, and increase both the EEA and FRA to maintain a 5-year gap between them. Although all three options would improve system solvency by similar proportions, their effect on individual beneficiaries in the future would vary. Benefit reductions are greater under the proposals with more months between the EEA and FRA, while the option that maintains a 4-year gap results in benefit increases for some beneficiaries compared with current law. PMID:23397744

  2. Are Noachian-age ridged plains (Nplr) actually early Hesperian in age

    NASA Technical Reports Server (NTRS)

    Frey, Herbert V.; Doudnikoff, C. E.; Mongeon, A. M.

    1990-01-01

    Whether or not the Nplr units in Memnonia and Argyre truly represent ridged plains volcanism of Noachian age or are simply areas of younger (Early Hesperian age) volcanism which failed to bury older craters and therefore have a greater total crater age than really applies to the ridged plains portion of those terrains is examined. The Nuekum and Hiller technique is used to determine the number of preserved crater retention surfaces in the Memnonia and Argyre regions where Scott and Tanaka show Nplr units to be common. The results for cratered terrain (Npl) in Memnonia is summarized along with those for ridged plains (Nplr) in both Memnonia and Argyre, and they are compared with similar results obtained for Tempe Terra and Lunae Plunum.

  3. The effect of a complex training and detraining programme on selected strength and power variables in early pubertal boys.

    PubMed

    Ingle, Lee; Sleap, Mike; Tolfrey, Keith

    2006-09-01

    Complex training, a combination of resistance training and plyometrics is growing in popularity, despite limited support for its efficacy. In pre- and early pubertal children, the study of complex training has been limited, and to our knowledge an examination of its effect on anaerobic performance characteristics of the upper and lower body has not been undertaken. Furthermore, the effect of detraining after complex training requires clarification. The physical characteristics (mean+/-s) of the 54 male participants in the present study were as follows: age 12.3 +/- 0.3 years, height 1.57 +/- 0.07 m, body mass 50.3 +/- 11.0 kg. Participants were randomly assigned to an experimental (n = 33) or control group (n = 21). The training, which was performed three times a week for 12 weeks, included a combination of dynamic constant external resistance and plyometrics. After training, participants completed 12 weeks of detraining. At baseline, after training and after detraining, peak and mean anaerobic power, dynamic strength and athletic performance were assessed. Twenty-six participants completed the training and none reported any training-related injury. Complex training was associated with small increases (< or =5.5%) in peak and mean power during training, followed by decreases of a similar magnitude (< or = -5.9%) during detraining (P < 0.05). No changes or minor, progressive increases (< or =1.5%) were evident in the control group (P > 0.05). In the experimental group, dynamic strength was increased by 24.3 - 71.4% (dependent on muscle group; P < 0.01), whereas growth-related changes in the control group varied from 0 to 4.4% (P > 0.05). For 40-m sprint running, basketball chest pass and vertical jump test performance, the experimental group saw a small improvement (< or =4.0%) after training followed by a decline (< or = -4.4%) towards baseline during detraining (P < 0.05), whereas the control group experienced no change (P > 0.05). In conclusion, in pre- and early

  4. The Relationship between Greater Pre-Pubertal Adiposity, Subsequent Age of Maturation and Bone Strength during Adolescence†

    PubMed Central

    Glass, Natalie A.; Torner, James C.; Letuchy, Elena M.; Burns, Trudy L.; Janz, Kathleen F.; Gilmore, Julie M. Eichenberger; Schlechte, Janet A.; Levy, Steven M.

    2016-01-01

    This longitudinal study investigated whether greater pre-pubertal adiposity was associated with subsequent timing of maturation and bone strength during adolescence in 135 girls and 123 boys participating in the Iowa Bone Development Study. Greater adiposity was defined using BMI data at age 8 years to classify participants as overweight (OW, ≥85th percentile for age and sex) or healthy-weight, HW). Maturation was defined as the estimated age of peak height velocity (PHV) based on a series of cross-sectional estimates. Measurements were taken at ages 11, 13, 15 and 17 years for estimates of body composition by DXA, bone compression (bone strength index) and torsion strength (polar strength-strain index) at the radius and tibia by pQCT, and femoral neck bending strength (section modulus) by hip structural analysis. Bone strength in OW versus HW were evaluated by fitting sex-specific linear mixed models that included centered age (visit age – grand mean age of cohort) as the time variable and adjusted for change in fat mass, and limb length in Model 1. Analyses were repeated using biological age (visit ageage PHV) as the time variable for Model 1 with additional adjustment for lean mass in Model 2. BMI was negatively associated with age of maturation (p<0.05). OW versus HW girls had significantly greater bone strength (p<0.001) in Model 1, while OW versus HW boys had significantly greater bone strength (p<0.001) at the tibia and femoral neck, but not radius (p>0.05). Analyses were repeated using biological age, which yielded reduced parameter estimates for girls but similar results for boys (Model 1.) Differences were no longer present following adjustment for lean mass (Model 2) in girls (p>0.05) while differences at the tibia were sustained in boys (p<0.05). These findings demonstrate sex- and site-specific differences in the associations between adiposity, maturation and bone strength. PMID:26861036

  5. The fragile elderly hip: Mechanisms associated with age-related loss of strength and toughness☆

    PubMed Central

    Reeve, Jonathan; Loveridge, Nigel

    2014-01-01

    Every hip fracture begins with a microscopic crack, which enlarges explosively over microseconds. Most hip fractures in the elderly occur on falling from standing height, usually sideways or backwards. The typically moderate level of trauma very rarely causes fracture in younger people. Here, this paradox is traced to the decline of multiple protective mechanisms at many length scales from nanometres to that of the whole femur. With normal ageing, the femoral neck asymmetrically and progressively loses bone tissue precisely where the cortex is already thinnest and is also compressed in a sideways fall. At the microscopic scale of the basic remodelling unit (BMU) that renews bone tissue, increased numbers of actively remodelling BMUs associated with the reduced mechanical loading in a typically inactive old age augments the numbers of mechanical flaws in the structure potentially capable of initiating cracking. Menopause and over-deep osteoclastic resorption are associated with incomplete BMU refilling leading to excessive porosity, cortical thinning and disconnection of trabeculae. In the femoral cortex, replacement of damaged bone or bone containing dead osteocytes is inefficient, impeding the homeostatic mechanisms that match strength to habitual mechanical usage. In consequence the participation of healthy osteocytes in crack-impeding mechanisms is impaired. Observational studies demonstrate that protective crack deflection in the elderly is reduced. At the most microscopic levels attention now centres on the role of tissue ageing, which may alter the relationship between mineral and matrix that optimises the inhibition of crack progression and on the role of osteocyte ageing and death that impedes tissue maintenance and repair. This review examines recent developments in the understanding of why the elderly hip becomes fragile. This growing understanding is suggesting novel testable approaches for reducing risk of hip fracture that might translate into control

  6. Upper Limb Strength and Muscle Volume in Healthy Middle-Aged Adults.

    PubMed

    Saul, Katherine R; Vidt, Meghan E; Gold, Garry E; Murray, Wendy M

    2015-12-01

    Our purpose was to characterize shoulder muscle volume and isometric moment, as well as their relationship, for healthy middle- aged adults. Muscle volume and maximum isometric joint moment were assessed for 6 functional muscle groups of the shoulder, elbow, and wrist in 10 middle-aged adults (46–60 y, 5M, 5F). Compared with young adults, shoulder abductors composed a smaller percentage of total muscle volume (P = .0009) and there was a reduction in shoulder adductor strength relative to elbow flexors (P = .012). We observed a consistent ordering of moment-generating capacity among functional groups across subjects. Although total muscle volume spanned a 2.3-fold range, muscle volume was distributed among functional groups in a consistent manner across subjects. On average, 72% of the variation in joint moment could be explained by the corresponding functional group muscle volume. These data are useful for improved modeling of upper limb musculoskeletal performance in middle-aged subjects, and may improve computational predictions of function for this group. PMID:26155870

  7. Water consumption in Iron Age, Roman, and Early Medieval Croatia.

    PubMed

    Lightfoot, E; Slaus, M; O'Connell, T C

    2014-08-01

    Patterns of water consumption by past human populations are rarely considered, yet drinking behavior is socially mediated and access to water sources is often socially controlled. Oxygen isotope analysis of archeological human remains is commonly used to identify migrants in the archeological record, but it can also be used to consider water itself, as this technique documents water consumption rather than migration directly. Here, we report an oxygen isotope study of humans and animals from coastal regions of Croatia in the Iron Age, Roman, and Early Medieval periods. The results show that while faunal values have little diachronic variation, the human data vary through time, and there are wide ranges of values within each period. Our interpretation is that this is not solely a result of mobility, but that human behavior can and did lead to human oxygen isotope ratios that are different from that expected from consumption of local precipitation.

  8. Water consumption in Iron Age, Roman, and Early Medieval Croatia.

    PubMed

    Lightfoot, E; Slaus, M; O'Connell, T C

    2014-08-01

    Patterns of water consumption by past human populations are rarely considered, yet drinking behavior is socially mediated and access to water sources is often socially controlled. Oxygen isotope analysis of archeological human remains is commonly used to identify migrants in the archeological record, but it can also be used to consider water itself, as this technique documents water consumption rather than migration directly. Here, we report an oxygen isotope study of humans and animals from coastal regions of Croatia in the Iron Age, Roman, and Early Medieval periods. The results show that while faunal values have little diachronic variation, the human data vary through time, and there are wide ranges of values within each period. Our interpretation is that this is not solely a result of mobility, but that human behavior can and did lead to human oxygen isotope ratios that are different from that expected from consumption of local precipitation. PMID:24888560

  9. Effects of strength, endurance and combined training on muscle strength, walking speed and dynamic balance in aging men.

    PubMed

    Holviala, J; Kraemer, W J; Sillanpää, E; Karppinen, H; Avela, J; Kauhanen, A; Häkkinen, A; Häkkinen, K

    2012-04-01

    The aim of this study was to examine effects of 21-week twice weekly strength (ST), endurance (ET) and combined (ST + ET 2 + 2 times a week) (SET) training on neuromuscular, endurance and walking performances as well as balance. 108 healthy men (56.3 ± 9.9 years) were divided into three training (ST; n = 30, ET; n = 26, SET; n = 31) groups and controls (C n = 21). Dynamic 1RM and explosive leg presses (1RMleg, 50%1RMleg), peak oxygen uptake using a bicycle ergometer (VO(2peak)), 10 m loaded walking time (10WALK) and dynamic balance distance (DYND) were measured. Significant increases were observed in maximal 1RMleg of 21% in ST (p < 0.001) and 22% in SET (p < 0.001) and in explosive 50%1RMleg of 7.5% in ST (p = 0.005) and 10.2% in SET (p < 0.001). VO(2peak) increased by 12.5% in ET (p = 0.001) and 9.8% in SET (p < 0.001). Significant decreases occurred in 10WALK in ST (p < 0.001) and SET (p = 0.003) and also in DYND of -10.3% in ST (p = 0.002) and -8% in SET (p = 0.028). The changes in C remained minor in all variables. In conclusion, ST and SET training produced significant improvements in maximal and explosive strength, walking speed and balance without any interference effect in SET. Significant but moderate relationships were observed between strength and dynamic balance and walking speed, while no corresponding correlations were found in the ET group.

  10. Narrative development in late talkers: early school age.

    PubMed

    Paul, R; Hernandez, R; Taylor, L; Johnson, K

    1996-12-01

    Children with slow expressive language development (SELD) as toddlers and a control group of children with normal language development (NL) were followed to early school age. Children with SELD were, at that point, subdivided into two groups: those who had moved within the normal range of expressive language (the History of Expressive Language Delay [HELD] subgroup); and those who continued to score below the normal range in expressive language at school age (the Expressive Language Delay [ELD] subgroup). During their kindergarten, first, and second grade years, they were administered a narrative generation task. Narratives were analyzed for MLU, lexical diversity, amount of information included, proportion of complete cohesive ties, and overall stage of narrative maturity. In kindergarten, children with normal language history scored significantly higher than those with HELD and ELD on lexical diversity and narrative stage; and higher than those with ELD in proportion of complete cohesive ties. In first grade, children with normal language history again scored significantly higher than those with HELD and ELD on narrative maturity, with no other significant differences. In second grade, there were no significant differences among the groups. PMID:8959614

  11. Are Noachian-age ridged plains (Nplr) actually Early Hesperian in age?. [Mars volcanology

    NASA Technical Reports Server (NTRS)

    Frey, H. V.; Doudnikoff, C. E.; Mongeon, A. M.

    1991-01-01

    The Nplr ridged plains studied are quite thin (less than 150 m, with some less than 90 m) based on the smallest surviving craters from the different preserved crater retention surfaces. The thinness of the Nplr ridged plains permits craters from older surfaces to show through, leading to a greater total crater count than actually applies to the ridged-plains component of those surfaces. It is found that the ridged-plains mapped as Noachian-age Nplr actually resurfaced older Noachian cratered terrain in the Early Hesperian, creating crater retention surfaces of N(1) equals (25,000 +/- 3000) in the Memnonia and Argyre regions.

  12. Effect of thermal aging on the tensile bond strength at reduced areas of seven current adhesives.

    PubMed

    Baracco, Bruno; Fuentes, M Victoria; Garrido, Miguel A; González-López, Santiago; Ceballos, Laura

    2013-07-01

    The purpose of this study was to determine the micro-tensile bond strength (MTBS) to dentin of seven adhesive systems (total and self-etch adhesives) after 24 h and 5,000 thermocycles. Dentin surfaces of human third molars were exposed and bonded with two total-etch adhesives (Adper Scotchbond 1 XT and XP Bond), two two-step self-etch adhesives (Adper Scotchbond SE and Filtek Silorane Adhesive System) and three one-step self-etch adhesives (G-Bond, Xeno V and Bond Force). All adhesive systems were applied following manufacturers' instructions. Composite buildups were constructed and the bonded teeth were then stored in water (24 h, 37 °C) or thermocycled (5,000 cycles) before being sectioned and submitted to MTBS test. Two-way ANOVA and subsequent comparison tests were applied at α = 0.05. Characteristic de-bonded specimens were analyzed using scanning electron microscopy (SEM). After 24 h water storage, MTBS values were highest with XP Bond, Adper Scotchbond 1 XT, Filtek Silorane Adhesive System and Adper Scotchbond SE and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. After thermocycling, MTBS values were highest with XP Bond, followed by Filtek Silorane Adhesive System, Adper Scotchbond SE and Adper Scotchbond 1 XT and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. Thermal aging induced a significant decrease in MTBS values with all adhesives tested. The resistance of resin-dentin bonds to thermal-aging degradation was material dependent. One-step self-etch adhesives obtained the lowest MTBS results after both aging treatments, and their adhesive capacity was significantly reduced after thermocycling.

  13. Effect of thermal aging on the tensile bond strength at reduced areas of seven current adhesives.

    PubMed

    Baracco, Bruno; Fuentes, M Victoria; Garrido, Miguel A; González-López, Santiago; Ceballos, Laura

    2013-07-01

    The purpose of this study was to determine the micro-tensile bond strength (MTBS) to dentin of seven adhesive systems (total and self-etch adhesives) after 24 h and 5,000 thermocycles. Dentin surfaces of human third molars were exposed and bonded with two total-etch adhesives (Adper Scotchbond 1 XT and XP Bond), two two-step self-etch adhesives (Adper Scotchbond SE and Filtek Silorane Adhesive System) and three one-step self-etch adhesives (G-Bond, Xeno V and Bond Force). All adhesive systems were applied following manufacturers' instructions. Composite buildups were constructed and the bonded teeth were then stored in water (24 h, 37 °C) or thermocycled (5,000 cycles) before being sectioned and submitted to MTBS test. Two-way ANOVA and subsequent comparison tests were applied at α = 0.05. Characteristic de-bonded specimens were analyzed using scanning electron microscopy (SEM). After 24 h water storage, MTBS values were highest with XP Bond, Adper Scotchbond 1 XT, Filtek Silorane Adhesive System and Adper Scotchbond SE and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. After thermocycling, MTBS values were highest with XP Bond, followed by Filtek Silorane Adhesive System, Adper Scotchbond SE and Adper Scotchbond 1 XT and lowest with the one-step self-etch adhesives Bond Force, Xeno V and G-Bond. Thermal aging induced a significant decrease in MTBS values with all adhesives tested. The resistance of resin-dentin bonds to thermal-aging degradation was material dependent. One-step self-etch adhesives obtained the lowest MTBS results after both aging treatments, and their adhesive capacity was significantly reduced after thermocycling. PMID:22790477

  14. Prediction of early-age shrinkage cracking in concrete elements

    NASA Astrophysics Data System (ADS)

    Weiss, William Jason

    1999-11-01

    When concrete is prevented from shrinking freely, tensile stresses develop which frequently result in cracking. Cracks in reinforced concrete structures reduce overall durability by allowing the penetration of water and aggressive agents, thereby accelerating the deterioration of the reinforcing steel. Highway pavements, bridge decks, and industrial floors are especially susceptible to this type of deterioration since these structures exhibit high rates of shrinkage and are frequently exposed to aggressive environmental conditions. The objectives of this investigation included the development of experimental procedures for assessing shrinkage cracking potential, the evaluation of mix composition on shrinkage cracking potential, and the development of theoretical models to simulate early-age cracking behavior. Specifically, the influence of a shrinkage-reducing admixture (SRA) was investigated. The shrinkage-reducing admixture substantially reduces free shrinkage and restrained shrinkage cracking while providing similar mechanical properties. An experimental procedure was developed in which a pressurized cylindrical specimen was used to assess tensile creep. Electrical properties were investigated using impedance spectroscopy to evaluate the moisture profiles of drying and wetting concrete. Restrained shrinkage experiments were developed and shrinkage cracking was shown to be size/geometry dependent, even though shrinkage strains and residual stress levels were comparable. A fracture mechanics modeling approach was developed to predict the behavior of a variety of restrained concrete specimens. This modeling approach was used to successfully explain experimental results from a variety of mixture compositions and specimen geometries. The model was used to demonstrate the influence of material and structural properties on the potential for cracking. A favorable correlation was observed between the predictions of the fracture-based model and the experimentally observed

  15. Lower-extremity strength profiles and gender-based classification of basketball players ages 9-22 years.

    PubMed

    Buchanan, Patricia A; Vardaxis, Vassilios G

    2009-03-01

    Despite an increase in women sports participants and recognition of gender differences in injury patterns (e.g., knee), few normative strength data exist beyond hamstrings and quadriceps measures. This study had 2 purposes: to assess the lower-extremity strength of women (W) and men (M) basketball players who were 9-22 years old, and to determine which strength measures most correctly classify the gender of 12- to 22-year-old athletes. Fifty basketball players (26 W, 24 M) without ligamentous or meniscal injury performed concentric isokinetic testing of bilateral hip, knee, and ankle musculature. We identified maximal peak torques for the hip (flexors, extensors, abductors, adductors), knee (flexors and extensors), and ankle (plantar flexors and dorsiflexors), and we formed periarticular (hip, knee, and ankle), antigravity, and total leg strength composite measures. We calculated mean and 95% confidence intervals. With body mass-height normalization, most age and gender differences were small. Mean values were typically higher for older vs. younger players and for men vs. women players. Mean values were often lower for girls 12-13 years vs. those 9-10 years. In the age group of 16-22 years, men had stronger knee flexors, hip flexors, plantar flexors, and total leg strength than women. Men who were 16-22 years old had stronger knee flexors and hip flexors than did younger men and women players. Based on discriminant function, knee strength measures did not adequately classify gender. Instead, total leg strength measures had correct gender classifications of 74 and 69% (jackknifed) with significant multivariate tests (p = 0.025). For researchers and practitioners, these results support strength assessment and training of the whole lower extremity, not just knee musculature. Limited strength differences between girls 9-10 years old and those 12-13 years old suggest that the peripubertal period is an important time to target strength development.

  16. Effect of Strain-Induced Age Hardening on Yield Strength Improvement in Ferrite-Austenite Duplex Lightweight Steels

    NASA Astrophysics Data System (ADS)

    Song, Hyejin; Lee, Seok Gyu; Sohn, Seok Su; Kwak, Jai-Hyun; Lee, Sunghak

    2016-11-01

    Ferrite-austenite lightweight steels showing TRansformation-induced plasticity were developed by varying the aging temperature with or without prestraining, and their effects on tensile properties were investigated in relation with microstructural evolution of carbide formation. The aged steels contained austenite, pearlite, and martensite in the ferrite matrix, and the austenite volume fraction decreased with the increasing aging temperature because some austenite grains decomposed to pearlites. This austenite decomposition to pearlite was favorable for the improvement of yield strength, but negatively influenced overall tensile properties. The prestraining promoted the austenite decomposition by a diffusion-controlled phase transformation, and changed the morphology of the cementite from a long lamellar shape to a densely agglomerated particle shape. In order to obtain the large increase in yield strength as well as excellent combination of strength and ductility, the strain-induced aging treatment, i.e., prestraining followed by aging, is important like in the prestrained and 673 K (400 °C)-aged steel. This large increase in yield strength, in spite of a reduction of elongation (65 to 43 pct), was basically attributed to an appropriate amount of decomposition of austenite to pearlite ( e.g., 4 vol pct), while having sufficient austenite to martensite transformation ( e.g., 14.5 vol pct martensite).

  17. Sarcopenia, Dynapenia, and the Impact of Advancing Age on Human Skeletal Muscle Size and Strength; a Quantitative Review

    PubMed Central

    Mitchell, W. Kyle; Williams, John; Atherton, Philip; Larvin, Mike; Lund, John; Narici, Marco

    2012-01-01

    Changing demographics make it ever more important to understand the modifiable risk factors for disability and loss of independence with advancing age. For more than two decades there has been increasing interest in the role of sarcopenia, the age-related loss of muscle or lean mass, in curtailing active and healthy aging. There is now evidence to suggest that lack of strength, or dynapenia, is a more constant factor in compromised wellbeing in old age and it is apparent that the decline in muscle mass and the decline in strength can take quite different trajectories. This demands recognition of the concept of muscle quality; that is the force generating per capacity per unit cross-sectional area (CSA). An understanding of the impact of aging on skeletal muscle will require attention to both the changes in muscle size and the changes in muscle quality. The aim of this review is to present current knowledge of the decline in human muscle mass and strength with advancing age and the associated risk to health and survival and to review the underlying changes in muscle characteristics and the etiology of sarcopenia. Cross-sectional studies comparing young (18–45 years) and old (>65 years) samples show dramatic variation based on the technique used and population studied. The median of values of rate of loss reported across studies is 0.47% per year in men and 0.37% per year in women. Longitudinal studies show that in people aged 75 years, muscle mass is lost at a rate of 0.64–0.70% per year in women and 0.80–00.98% per year in men. Strength is lost more rapidly. Longitudinal studies show that at age 75 years, strength is lost at a rate of 3–4% per year in men and 2.5–3% per year in women. Studies that assessed changes in mass and strength in the same sample report a loss of strength 2–5 times faster than loss of mass. Loss of strength is a more consistent risk for disability and death than is loss of muscle mass. PMID:22934016

  18. Electrical Muscle Stimulation: An Effective Form of Exercise and Early Mobilization to Preserve Muscle Strength in Critically Ill Patients

    PubMed Central

    Karatzanos, Eleftherios; Gerovasili, Vasiliki; Zervakis, Dimitrios; Tripodaki, Elli-Sophia; Apostolou, Kleovoulos; Vasileiadis, Ioannis; Papadopoulos, Emmanouil; Mitsiou, Georgios; Tsimpouki, Dimitra; Routsi, Christina; Nanas, Serafim

    2012-01-01

    Purpose. This is a secondary analysis of previously published data to investigate the effects of electrical muscle stimulation (EMS) on strength of various muscle groups in critically ill patients. Methods. One hundred forty-two consecutive patients, with APACHE II score ≥ 13, were randomly assigned to the EMS or the control group. EMS sessions were applied daily on vastus lateralis, vastus medialis, and peroneus longus of both lower extremities. Various muscle groups were evaluated with the Medical Research Council (MRC) scale for muscle strength. Handgrip strength assessment was also employed. Results. Twenty four patients in the EMS group and 28 patients in the control group were finally evaluated. EMS patients achieved higher MRC scores than controls (P ≤ 0.05) in wrist flexion, hip flexion, knee extension, and ankle dorsiflexion. Collectively, the EMS group performed higher (P < 0.01) in the legs and overall. Handgrip strength correlated (P ≤ 0.01) with the upper and lower extremities' muscle strength and the overall MRC scores. Conclusions. EMS has beneficial effects on the strength of critically ill patients mainly affecting muscle groups stimulated, while it may also affect muscle groups not involved presenting itself as a potential effective means of muscle strength preservation and early mobilization in this patient population. PMID:22545212

  19. ATLIS. Early Childhood Development and the Electronic Age.

    ERIC Educational Resources Information Center

    Alexander, Nancy P.

    1994-01-01

    Describes the America Tomorrow Leadership Information Service (ATLIS) and how this information can benefit early childhood professionals. Discusses the future of telecommunications in the early childhood profession and includes a glossary of telecommunications terms. (HTH)

  20. Association between muscular strength and inflammatory markers among elderly persons with cardiac disease: results from the KORA-Age study.

    PubMed

    Volaklis, K A; Halle, M; Koenig, W; Oberhoffer, R; Grill, E; Peters, A; Strasser, B; Heier, M; Emeny, R; Schulz, H; Ladwig, K H; Meisinger, C; Thorand, B

    2015-11-01

    Little is known about the association between muscle strength and inflammation in diseased individuals and particularly in cardiac patients. Thus, our purpose was to examine the association of muscular strength with the inflammatory status in older adults with and without cardiac disease. The cross-sectional analysis was based on 1079 adults aged 65-94 years, who participated in the KORA-Age study. Participants underwent an interview and extensive physical examinations including anthropometric measurements, registration of diseases and drug intake, determination of health-related behaviors, collection of blood samples for measurements of interleukin-6 and hs-CRP and muscle strength measurement using hand-grip dynamometry. Cardiac patients (n = 323) had higher levels of IL-6 and poorer muscle strength compared with older adults without cardiac disease. Among persons with cardiac diseases, muscle strength in the lower tertile compared to the upper tertile was significantly associated with increased odds of having elevated IL-6 levels (OR 3.53, 95 % CI 1.18-10.50, p = 0.024) after controlling for age, gender, body fat, alcohol intake, smoking status, diseases, medications and physical activity, whereas the association between muscle strength and hs-CRP remained borderline significant (OR 2.80, 95 % CI 0.85-9.24, p = 0.092). The same trends, with slightly lower odds ratios, were also observed in older adults without cardiac disease. Lower levels of muscular strength are associated with higher concentrations of IL-6 and hs-CRP in elderly individuals with and without cardiac disease suggesting a significant contribution of the muscular system in reducing low-grade inflammation that accompanies cardiac disease and aging.

  1. Strength Training and Testosterone Treatment Have Opposing Effects on Migration Inhibitor Factor Levels in Ageing Men

    PubMed Central

    Glintborg, D.; Christensen, L. L.; Kvorning, T.; Larsen, R.; Brixen, K.; Hougaard, D. M.; Richelsen, B.; Bruun, J. M.; Andersen, M.

    2013-01-01

    Background. The beneficial effects of testosterone treatment (TT) are debated. Methods. Double-blinded, placebo-controlled study of six months TT (gel) in 54 men aged 60–78 with bioavailable testosterone (BioT) <7.3 nmol/L and waist >94 cm randomized to TT (50–100 mg/day, n = 20), placebo (n = 18), or strength training (ST) (n = 16) for 24 weeks. Moreover, the ST group was randomized to TT (n = 7) or placebo (n = 9) after 12 weeks. Outcomes. Chemokines (MIF, MCP-1, and MIP-1α) and lean body mass (LBM), total, central, extremity, visceral, and subcutaneous (SAT) fat mass established by DXA and MRI. Results. From 0 to 24 weeks, MIF and SAT decreased during ST + placebo versus placebo, whereas BioT and LBM were unchanged. TT decreased fat mass (total, central, extremity, and SAT) and increased BioT and LBM versus placebo. MIF levels increased during TT versus ST + placebo. ST + TT decreased fat mass (total, central, and extremity) and increased BioT and LBM versus placebo. From 12 to 24 weeks, MCP-1 levels increased during TT versus placebo and MCP-1 levels decreased during ST + placebo versus placebo. Conclusion. ST + placebo was associated with decreased MIF levels suggesting decreased inflammatory activity. TT may be associated with increased inflammatory activity. This trial is registered with ClinicalTrials.gov NCT00700024. PMID:24089589

  2. Femoral neck bone strength estimated by hip structural analysis (HSA) in Swedish Caucasians aged 6-90 years.

    PubMed

    Alwis, Gayani; Karlsson, Caroline; Stenevi-Lundgren, Susanna; Rosengren, Björn E; Karlsson, Magnus K

    2012-03-01

    Dual-energy X-ray absorptiometry hip scans of 1,760 population-based Caucasians, 599 girls and 642 boys aged 6-19 years and 270 women and 249 men aged 20-90 years, were analyzed with the hip structural analysis (HSA) software to present age- and sex-specific normative HSA data of the femoral neck (FN). Measured traits included bone mineral density (BMD), cross-sectional area (CSA), section modulus (Z), periosteal diameter (PD), endosteal diameter (ED), cortical thickness (CT), and cross-sectional moment of inertia (CSMI). When plotting the measured traits versus age, the curves increased with higher ages until statistically significant break points were reached, for all traits at age 17 in girls and age 19 in boys. After the break points, PD and ED increased with higher ages but, as ED increased more than PD, BMD and CT decreased significantly with higher ages. The decline in BMD was counteracted by the increase in bone size so that there was only a nonstatistically significant decrease in bone strength, estimated as Z and CSMI, from break point to age 90. The partial preservation of bone strength was more obvious in men than in women as the decline in BMD was higher in women than in men, while the expansion in PD was larger in men than in women. The sex difference in the normative FN bone strength data seems to be related to sex discrepancies in the development of both bone mass and geometrical parameters during both growth and adulthood.

  3. Age 26 Cost-Benefit Analysis of the Child-Parent Center Early Education Program

    ERIC Educational Resources Information Center

    Reynolds, Arthur J.; Temple, Judy A.; White, Barry A. B.; Ou, Suh-Ruu; Robertson, Dylan L.

    2011-01-01

    Using data collected up to age 26 in the Chicago Longitudinal Study, this cost-benefit analysis of the Child-Parent Centers (CPC) is the first for a sustained publicly funded early intervention. The program provides services for low-income families beginning at age 3 in 20 school sites. Kindergarten and school-age services are provided up to age 9…

  4. Effects of aging on P300 between late young-age and early middle-age adulthood: an electroencephalogram event-related potential study.

    PubMed

    Bourisly, Ali K

    2016-09-28

    The aim of this study was to identify age-related changes of P300 peak amplitude and P300 latency between closely separated nonsenile age groups (late young-aged adults and early middle-aged adults) and to investigate whether or not P300 has the potential to be used as a measure of cognitive aging even among nonsenile age groups. Twenty-eight adults (25-55 years old) completed an event-related potential oddball task. The elicitation of both P300 peak amplitude and P300 latency indicated age-related changes of P300. The results of the study showed that the P300 target peak amplitude was significantly larger in late young age compared with early middle age and that P300 target latency was also significantly delayed in early middle age compared with late young age. The results of this work contribute toward research efforts on a consensus on how aging affects event-related potential and/or P300. The main conclusions are that there exist significant age-related P300 changes even between closely separated, relatively younger, and nonsenile age groups, and that P300 has the potential to be used as a measure for cognitive aging even in nonsenile adults.

  5. Starting with Their Strengths: Using the Project Approach in Early Childhood Special Education. Early Childhood Education Series

    ERIC Educational Resources Information Center

    Lickey, Deborah C.; Powers, Denise J.

    2011-01-01

    This book provides a comprehensive and practical guide to using the project approach when teaching young children with special needs. While focusing on children's individual strengths, which include their interests, intelligences, and unique styles of learning, this resource demonstrates teaching strategies that address multiple areas of…

  6. State Developments in Child Care, Early Education, and School-Age Care, 2001.

    ERIC Educational Resources Information Center

    Ewen, Danielle; Blank, Helen; Hart, Katherine; Schulman, Karen

    This report provides highlights and updates regarding state actions on child care, early education, and school-age care issues during 2001. It is intended to serve as a supplement to "State Developments in Child Care, Early Education, and School-Age Care 2000" and various reports published on this issue between 1997 and 1999. Information in the…

  7. Dietary habits of Mongolian people, and their influence on lifestyle-related diseases and early aging.

    PubMed

    Komatsu, Fumio; Kagawa, Yasuo; Kawabata, Terue; Kaneko, Yoshinori; Purvee, Baatar; Otgon, Jugder; Chimedregzen, Ulziiburen

    2008-07-01

    Mongolians are known to have relatively short life expectancy. In order to examine the role of dietary habits in the early aging of Mongolians, the food intake inquiry, anthropometric measurements and blood clinical tests were performed for 365 healthy inhabitants in Murun, a northern Mongolia city, and compared to those of Japanese. Murun inhibitants were found to have a characteristic dietary habit of taking large amounts of meat, milk, dairy products and wheat flour products, in contrast little vegetables, fruits and fishes. The daily calorie intake of the adults was estimated to be 2,525 kcal, and the fat/total calorie ratio was calculated 33.7%, about 1.3-fold higher than that of Japanese. The intake ratio of fatty acid from the Mongolian foods, saturated : mono-unsaturated : poly-unsaturated fatty acids (PUFA) ratio, was 10.3 : 7.8 : 3.0. Results of blood clinical tests showed significantly higher levels of serum triglycerides, low-density lipoprotein cholesterol (LDL) and homocysteine, and lower levels of high-density lipoprotein cholesterol (HDL), n-3 PUFA, folic acid and adiponectin, in comparison with those of Japanese. In addition, the Mongolians were also found to have significantly high levels of oxidative stress markers, such as serum malondialdehyde-modified LDL (MDA-LDL), urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and serum reactive oxygen metabolites (ROM). The serum ROM level in the Mongolians seemed to associate with their body fat ratio (p<0.05), and was significantly inverse-correlated to handgrip strength (p<0.001). Obesity was observed at a high incidence in the subjects over 30-year old, and over 40-year old their handgrip ability was markedly decreased. These findings suggest that in the Mongolians the dietary habits associate with their lifestyle-related diseases and early aging, and the improvement of dietary habits is an effective strategy for health promotion of the inhabitants.

  8. Heterogeneity in resistance training-induced muscle strength and mass responses in men and women of different ages.

    PubMed

    Ahtiainen, Juha P; Walker, Simon; Peltonen, Heikki; Holviala, Jarkko; Sillanpää, Elina; Karavirta, Laura; Sallinen, Janne; Mikkola, Jussi; Valkeinen, Heli; Mero, Antti; Hulmi, Juha J; Häkkinen, Keijo

    2016-02-01

    Physical activity recommendations for public health include typically muscle-strengthening activities for a minimum of 2 days a week. The range of inter-individual variation in responses to resistance training (RT) aiming to improve health and well-being requires to be investigated. The purpose of this study was to quantify high and low responders for RT-induced changes in muscle size and strength and to examine possible effects of age and sex on these responses. Previously collected data of untrained healthy men and women (age 19 to 78 years, n = 287 with 72 controls) were pooled for the present study. Muscle size and strength changed during RT are 4.8 ± 6.1 % (range from -11 to 30 %) and 21.1 ± 11.5 % (range from -8 to 60 %) compared to pre-RT, respectively. Age and sex did not affect to the RT responses. Fourteen percent and 12 % of the subjects were defined as high responders (>1 standard deviation (SD) from the group mean) for the RT-induced changes in muscle size and strength, respectively. When taking into account the results of non-training controls (upper 95 % CI), 29 and 7 % of the subjects were defined as low responders for the RT-induced changes in muscle size and strength, respectively. The muscle size and strength responses varied extensively between the subjects regardless of subject's age and sex. Whether these changes are associated with, e.g., functional capacity and metabolic health improvements due to RT requires further studies.

  9. Dysfunction of mouse cerebral arteries during early aging

    PubMed Central

    Balbi, Matilde; Ghosh, Mitrajit; Longden, Thomas A; Jativa Vega, Max; Gesierich, Benno; Hellal, Farida; Lourbopoulos, Athanasios; Nelson, Mark T; Plesnila, Nikolaus

    2015-01-01

    Aging leads to a gradual decline in the fidelity of cerebral blood flow (CBF) responses to neuronal activation, resulting in an increased risk for stroke and dementia. However, it is currently unknown when age-related cerebrovascular dysfunction starts or which vascular components and functions are first affected. The aim of this study was to examine the function of microcirculation throughout aging in mice. Microcirculation was challenged by inhalation of 5% and 10% CO2 or by forepaw stimulation in 6-week, 8-month, and 12-month-old FVB/N mice. The resulting dilation of pial vessels and increase in CBF was measured by intravital fluorescence microscopy and laser Doppler fluxmetry, respectively. Neurovascular coupling and astrocytic endfoot Ca2+ were measured in acute brain slices from 18-month-old mice. We did not reveal any changes in CBF after CO2 reactivity up to an age of 12 months. However, direct visualization of pial vessels by in vivo microscopy showed a significant, age-dependent loss of CO2 reactivity starting at 8 months of age. At the same age neurovascular coupling was also significantly affected. These results suggest that aging does not affect cerebral vessel function simultaneously, but starts in pial microvessels months before global changes in CBF are detectable. PMID:26058694

  10. Early-phase adaptations of traditional-speed vs. superslow resistance training on strength and aerobic capacity in sedentary individuals.

    PubMed

    Keeler, L K; Finkelstein, L H; Miller, W; Fernhall, B

    2001-08-01

    We performed a randomized exercise training study to assess the effects of traditional Nautilus-style (TR) or superslow (SS) strength training on muscular strength, body composition, aerobic capacity, and cardiovascular endurance. Subjects were 14 healthy, sedentary women, 19-45 years of age (mean +/- SD age, 32.7 +/- 8.9 years), randomized to either the SS or TR training protocols and trained 3 times per week for 10 weeks. Measurements were taken both before and after training, which included a maximal incremental exercise test on a cycle ergometer, body composition, and 1 repetition maximum (1RM) tests on 8 Nautilus machines. Both groups increased their strength significantly on all 8 exercises, whereas the TR group increased significantly more than the SS group on bench press (34% vs. 11%), torso arm (anterior lateral pull-down) (27% vs. 12%), leg press (33% vs. 7%), leg extension (56% vs. 24%), and leg curl (40% vs. 15%). Thus, the TR group's improvement in total exercise weight lifted was significantly greater than that of the SS group after testing (39% vs. 15%). Exercise duration on the cycle ergometer and work rate significantly improved for both groups, but there was no group-by-training interaction. No significant differences were found for body composition or additional aerobic variables measured. Both strength training protocols produced a significant improvement in strength during a 10-week training period, but the TR protocol produced better gains in the absence of changes in percentage of body fat, body mass index, lean body mass, and body weight. In addition, strength training alone did not improve Vo2max, yet short-term endurance increased.

  11. The Developmental Progression of Age 14 Behavioral Disinhibition, Early Age of Sexual Initiation, and Subsequent Sexual Risk-Taking Behavior

    PubMed Central

    Samek, Diana R.; Iacono, William G.; Keyes, Margaret A.; Epstein, Marina; Bornovalova, Marina A.; McGue, Matt

    2013-01-01

    Background Research has demonstrated a consistent relationship between early sexual experience and subsequent sexual risk-taking behaviors. We hypothesized that this relationship is due to a general predisposition towards behavioral disinhibition (BD), and that relationships among BD, early sex, and subsequent risky sexual behavior may be influenced by common genetic influences for males and common environmental influences for females. Methods A prospective sample of 1,512 same-sex adolescent twins (50.2% female) was used. Adolescent BD was measured by clinical symptom counts of conduct disorder, oppositional defiant disorder, and self-reported delinquent behavior (age 14). Age of sexual initiation was defined as first age of consensual oral or penetrative sex (mean age ~17). Adult risky sexual behavior was defined by sexual behaviors under the influence of drugs and alcohol and number of casual sexual partners in the past year (age 24). Results Multivariate analyses showed evidence for substantial common genetic variance among age 14 BD, age at sexual initiation, and adult risky sexual behavior for males, but not females. There was no significant difference in the degree of common environmental influence on these variables for females compared to males. Notably, age of sexual initiation was not significantly correlated with age 24 risky sexual behavior for females. Conclusion The relationship between early sex and later risky sex can be better understood through a general liability towards BD, which is influenced primarily by genetic factors for males. The association between age 14 BD and age of sexual initiation was influenced through a combination of genetic and environmental factors for females; however, age of sexual initiation does not appear to be a salient predictor of adult women’s sexual risk-taking behavior. Findings suggest that prevention programs aimed at reducing sexual risk behavior might target youth exhibiting BD by age 14, particularly males

  12. Effect of Aging on Bond Strength of Two Soft Lining Materials to a Denture Base Polymer.

    PubMed

    Salloum, Alaa'a M

    2014-12-01

    The purpose of this study was evaluation the effect of immersion in distilled water and inorganic artificial saliva on the shear bond strength of a heat-polymerized and an auto-polymerized silicone-based denture lining materials. The denture liners investigated were Molloplast-B (heat-polymerized), and Mollosil plus (auto-polymerized). The soft liner specimens were 10 × 10 × 2.5 mm and were processed between two poly(methylmethacrylate) plates. Thirty shear specimens for each type of test lining material were prepared. Specimens were divided equally into three groups for each test lining material: first group, specimens were tested after 48 h of preparation without immersion; second group, specimens were tested following immersion in distilled water at 37 °C for 12 months; and third group, specimens were tested following immersion in inorganic artificial saliva at 37 °C for 12 months. Shear bond strength was measured using an universal testing machine at a crosshead speed of 40 mm/min and failure mode (adhesive, cohesive and mixed) after debonding was assessed. Data were statistically analyzed with one-way analysis of variance (ANOVA) (α = 0.05). ANOVA was followed by Bonferroni post hoc tests for pairwise comparisons. A significant difference in shear bond strength was detected between Molloplast-B and Mollosil plus following immersion in distilled water and artificial saliva. Molloplast-B demonstrated considerably higher shear strength than Mollosil plus after immersion. Shear strengths of the lining materials investigated reduced significantly after immersion in both solutions. Visual examination after separation revealed that the soft materials tested exhibited mostly adhesive failure. The effect of immersion in distilled water and inorganic artificial saliva on bond strength of test lining materials was perceivable; however, both of them had acceptable bond strength and might be proper for long-term use. PMID:26199507

  13. Early Bronze Age Dolmens in Jordan and their orientations

    NASA Astrophysics Data System (ADS)

    Polcaro, A.; Polcaro, F.

    This work presents the results of a survey of dolmen fields of the Early Bronze I in Jordan, in the Wadi Zarqa Valley, started in October 2004 and still in progress. Our data show, with a very high statistical significance, that in many sites of the Early Bronze IA a large majority of dolmens were built oriented along the N-S direction. A first interpretative hypothesis of these results, based on the astronomical contents of the mythology of the nearby civilizations culturally connected to the Palestinian area, is suggested.

  14. Burst strength behaviour of an aging subsea gas pipeline elbow in different external and internal corrosion-damaged positions

    NASA Astrophysics Data System (ADS)

    Lee, Geon Ho; Pouraria, Hassan; Seo, Jung Kwan; Paik, Jeom Kee

    2015-09-01

    Evaluation of the performance of aging structures is essential in the oil and gas industry, where the inaccurate prediction of structural performance can have significantly hazardous consequences. The effects of structure failure due to the significant reduction in wall thickness, which determines the burst strength, make it very complicated for pipeline operators to maintain pipeline serviceability. In other words, the serviceability of gas pipelines and elbows needs to be predicted and assessed to ensure that the burst or collapse strength capacities of the structures remain less than the maximum allowable operation pressure. In this study, several positions of the corrosion in a subsea elbow made of API X42 steel were evaluated using both design formulas and numerical analysis. The most hazardous corrosion position of the aging elbow was then determined to assess its serviceability. The results of this study are applicable to the operational and elbow serviceability needs of subsea pipelines and can help predict more accurate replacement or repair times.

  15. Burst strength behaviour of an aging subsea gas pipeline elbow in different external and internal corrosion-damaged positions

    NASA Astrophysics Data System (ADS)

    Lee, Geon Ho; Pouraria, Hassan; Seo, Jung Kwan; Paik, Jeom Kee

    2015-05-01

    Evaluation of the performance of aging structures is essential in the oil and gas industry, where the inaccurate prediction of structural performance can have significantly hazardous consequences. The effects of structure failure due to the significant reduction in wall thickness, which determines the burst strength, make it very complicated for pipeline operators to maintain pipeline serviceability. In other words, the serviceability of gas pipelines and elbows needs to be predicted and assessed to ensure that the burst or collapse strength capacities of the structures remain less than the maximum allowable operation pressure. In this study, several positions of the corrosion in a subsea elbow made of API X42 steel were evaluated using both design formulas and numerical analysis. The most hazardous corrosion position of the aging elbow was then determined to assess its serviceability. The results of this study are applicable to the operational and elbow serviceability needs of subsea pipelines and can help predict more accurate replacement or repair times.

  16. Exploring Work and Development Options to Reduce Early Labour Force Exit of Mature Aged Australians

    ERIC Educational Resources Information Center

    Pillay, Hitendra; Kelly, Kathy; Tones, Megan

    2008-01-01

    Early labour force exit is a significant challenge associated with the ageing workforce in Australia and many other developed countries. A reduction and increased flexibility of work hours has been suggested to improve labour force participation of the mature aged cohort. However, little is known about mature aged workers' aspirations for…

  17. Early Learning Left Out: An Examination of Public Investments in Education and Development by Child Age

    ERIC Educational Resources Information Center

    Bruner, Charles; Elias, Victor; Stein, Debbie; Schaefer, Stephanie

    2004-01-01

    This study presents the most comprehensive picture, to date, of public investments in the education and development of children by three age groupings--the early learning years (roughly 0-5), the school-aged years (roughly 6-18), and the college-aged years (roughly 19-23). It is based upon detailed analysis of state, federal, and school district…

  18. Low ponderal index is associated with decreased muscle strength and fatigue resistance in college-aged women

    PubMed Central

    Brutsaert, Tom D.; Tamvada, Kelli H.; Kiyamu, Melisa; White, Daniel D.; Gage, Timothy B

    2011-01-01

    Poor fetal growth is associated with decrements in muscle strength likely due to changes during myogenesis. We investigated the association of poor fetal growth with muscle strength, fatigue resistance, and the response to training in the isolated quadriceps femoris. Females (20.6 yrs) born to term but below the 10th percentile of ponderal index (PI)-for-gestational-age (LOWPI, n=14) were compared to controls (HIGHPI, n=14), before and after an 8-week training. Muscle strength was assessed as grip-strength and as the maximal isometric voluntary contraction (MVC) of the quadriceps femoris. Muscle fatigue was assessed during knee extension eercise. Body composition and the maximal oxygen consumption (VO2max) were also measured. Controlling for fat free mass (FFM), LOWPI versus HIGHPI women had ~11% lower grip-strength (P=0.023), 9–24% lower MVC values (P=0.042 pre-trained; P=0.020 post-trained), a higher rate of fatigue (pre- and post-training), and a diminished training response (P=0.016). Statistical control for FFM increased rather than decreased strength differences between PI groups. The PI was not associated with VO2max or measures of body composition. Strength and fatigue decrements strongly suggest that poor fetal growth affects the pathway of muscle force generation. This could be due to neuromotor and/or muscle morphologic changes during development e.g., fiber number, fiber type, etc. Muscle from LOWPI women may also be less responsive to training. Indirectly, results also implicate muscle as a potential mediator between poor fetal growth and adult chronic disease, given muscle’s direct role in determining insulin resistance, type II diabetes, physical activity, and so forth. PMID:21641734

  19. Early Adolescent Perceptions of Neighborhood: Strengths, Structural Disadvantage, and Relations to Outcomes

    ERIC Educational Resources Information Center

    Witherspoon, Dawn P.; Hughes, Diane L.

    2014-01-01

    Considerable evidence shows the detriments of neighborhood social disorganization for urban youth. Researchers have focused less on potential neighborhood strengths or on the interplay of neighborhood perceptions and objective neighborhood characteristics. The authors examined the presence and perception of positive and negative neighborhood…

  20. Microarray Analysis of Genes Involved with Shell Strength in Layer Shell Gland at the Early Stage of Active Calcification

    PubMed Central

    Liu, Zhangguo; Zheng, Qi; Zhang, Xueyu; Lu, Lizhi

    2013-01-01

    The objective of this study was to get a comprehensive understanding of how genes in chicken shell gland modulate eggshell strength at the early stage of active calcification. Four 32-week old of purebred Xianju hens with consistent high or low shell breakage strength were grouped into two pairs. Using Affymetrix Chicken Array, a whole-transcriptome analysis was performed on hen’s shell gland at 9 h post oviposition. Gene ontology enrichment analysis for differentially expressed (DE) transcripts was performed using the web-based GOEAST, and the validation of DE-transcripts was tested by qRT-PCR. 1,195 DE-transcripts, corresponding to 941 unique genes were identified in hens with strong eggshell compared to weak shell hens. According to gene ontology annotations, there are 77 DE-transcripts encoding ion transporters and secreted extracellular matrix proteins, and at least 26 DE-transcripts related to carbohydrate metabolism or post-translation glycosylation modification; furthermore, there are 88 signaling DE-transcripts. GO term enrichment analysis suggests that some DE-transcripts mediate reproductive hormones or neurotransmitters to affect eggshell quality through a complex suite of biophysical processes. These results reveal some candidate genes involved with eggshell strength at the early stage of active calcification which may facilitate our understanding of regulating mechanisms of eggshell quality. PMID:25049830

  1. Rapamycin increases grip strength and attenuates age-related decline in maximal running distance in old low capacity runner rats

    PubMed Central

    Xue, Qian-Li; Yang, Huanle; Li, Hui-Fen; Abadir, Peter M.; Burks, Tyesha N.; Koch, Lauren G.; Britton, Steven L.; Carlson, Joshua; Chen, Laura; Walston, Jeremy D.; Leng, Sean X.

    2016-01-01

    Rapamycin is known to extend lifespan. We conducted a randomized placebo-controlled study of enteric rapamycin-treatment to evaluate its effect on physical function in old low capacity runner (LCR) rats, a rat model selected from diverse genetic background for low intrinsic aerobic exercise capacity without genomic manipulation and characterized by increased complex disease risks and aging phenotypes. The study was performed in 12 male and 16 female LCR rats aged 16-22 months at baseline. The treatment group was fed with rapamycin-containing diet pellets at approximately 2.24mg/kg body weight per day and the placebo group with the same diet without rapamycin for six months. Observation was extended for additional 2 months. Physical function measurements include grip strength measured as maximum tensile force using a rat grip strength meter and maximum running distance (MRD) using rat physical treadmill test. The results showed that rapamycin improved grip strength by 13% (p=.036) and 60% (p<.001) from its baseline in female and male rats, respectively. Rapamycin attenuated MRD decline by 66% (p<.001) and 46% (p=.319) in females and males, respectively. These findings provide initial evidence for beneficial effect of rapamycin on physical functioning in an aging rat model of high disease risks with significant implication in humans. PMID:26997106

  2. Role of the nervous system in sarcopenia and muscle atrophy with aging: strength training as a countermeasure.

    PubMed

    Aagaard, P; Suetta, C; Caserotti, P; Magnusson, S P; Kjaer, M

    2010-02-01

    Aging is characterized by loss of spinal motor neurons (MNs) due to apoptosis, reduced insulin-like growth factor I signaling, elevated amounts of circulating cytokines, and increased cell oxidative stress. The age-related loss of spinal MNs is paralleled by a reduction in muscle fiber number and size (sarcopenia), resulting in impaired mechanical muscle performance that in turn leads to a reduced functional capacity during everyday tasks. Concurrently, maximum muscle strength, power, and rate of force development are decreased with aging, even in highly trained master athletes. The impairment in muscle mechanical function is accompanied and partly caused by an age-related loss in neuromuscular function that comprise changes in maximal MN firing frequency, agonist muscle activation, antagonist muscle coactivation, force steadiness, and spinal inhibitory circuitry. Strength training appears to elicit effective countermeasures in elderly individuals even at a very old age (>80 years) by evoking muscle hypertrophy along with substantial changes in neuromuscular function, respectively. Notably, the training-induced changes in muscle mass and nervous system function leads to an improved functional capacity during activities of daily living.

  3. Aging enhances a mechanically-induced reduction in tendon strength by an active process involving matrix metalloproteinase activity.

    PubMed

    Dudhia, Jayesh; Scott, Charlotte M; Draper, Edward R C; Heinegård, Dick; Pitsillides, Andrew A; Smith, Roger K

    2007-08-01

    Age-associated and degenerative loss of functional integrity in soft tissues develops from effects of cumulative and subtle changes in their extracellular matrix (ECM). The highly ordered tendon ECM provides the tissue with its tensile strength during loading. As age and exercise collide in the high incidence of tendinopathies, we hypothesized that aged tendons fail due to cumulative damage resulting from a combination of diminished matrix repair and fragmentation of ECM proteins induced by prolonged cyclical loading, and that this is an active cell-mediated process. We developed an equine tendon explant model to examine the effect of age on the influence of prolonged cyclical loading at physiologically relevant strain rates (5% strain, 1 Hz for 24 h) on tissue mechanical properties, loss of ECM protein and matrix metalloproteinase (MMP) expression. We show significantly diminished mechanical strength of cyclically loaded tissue compared to controls (39.7 +/- 12%, P strength by an active process, and that MMPs may contribute to loss of functional competence, exaggerated by age, via load-induced proteolytic disruption of the ECM.

  4. Midlife muscle strength and human longevity up to age 100 years: a 44-year prospective study among a decedent cohort.

    PubMed

    Rantanen, Taina; Masaki, Kamal; He, Qimei; Ross, G Webster; Willcox, Bradley J; White, Lon

    2012-06-01

    We studied prospectively the midlife handgrip strength, living habits, and parents' longevity as predictors of length of life up to becoming a centenarian. The participants were 2,239 men from the Honolulu Heart Program/Honolulu-Asia Aging Study who were born before the end of June 1909 and who took part in baseline physical assessment in 1965-1968, when they were 56-68 years old. Deaths were followed until the end of June 2009 for 44 years with complete ascertainment. Longevity was categorized as centenarian (≥100 years, n = 47), nonagenarian (90-99 years, n = 545), octogenarian (80-89 years, n = 847), and ≤79 years (n = 801, reference). The average survival after baseline was 20.8 years (SD = 9.62). Compared with people who died at the age of ≤79 years, centenarians belonged 2.5 times (odds ratio (OR) = 2.52, 95% confidence interval (CI) = 1.23-5.10) more often to the highest third of grip strength in midlife, were never smokers (OR = 5.75 95% CI = 3.06-10.80), had participated in physical activity outside work (OR = 1.13 per daily hour, 95% CI = 1.02-1.25), and had a long-lived mother (≥80 vs. ≤60 years, OR = 2.3, 95% CI = 1.06-5.01). Associations for nonagenarians and octogenarians were parallel, but weaker. Multivariate modeling showed that mother's longevity and offspring's grip strength operated through the same or overlapping pathway to longevity. High midlife grip strength and long-lived mother may indicate resilience to aging, which, combined with healthy lifestyle, increases the probability of extreme longevity.

  5. Modeling old-age wealth with endogenous early-life outcomes: The case of Mexico.

    PubMed

    DeGraff, Deborah S; Wong, Rebeca

    2014-04-01

    This paper contributes to the literature on the life course and aging by examining the association between early-life outcomes and late-life well being, using data from the Mexican Health and Aging Study. Empirical research in this area has been challenged by the potential endogeneity of the early-life outcomes of interest, an issue which most studies ignore or downplay. Our contribution takes two forms: (1) we examine in detail the potential importance of two key life-cycle outcomes, age at marriage (a measure of family formation) and years of educational attainment (a measure of human capital investment) for old-age wealth, and (2) we illustrate the empirical value of past context variables that could help model the association between early-life outcomes and late-life well being. Our illustrative approach, matching macro-level historical policy and census variables to individual records to use as instruments in modeling the endogeneity of early-life behaviors, yields a statistically identified two-stage model of old-age wealth with minimum bias. We use simulations to show that the results for the model of wealth in old age are meaningfully different when comparing the approach that accounts for endogeneity with an approach that assumes exogeneity of early-life outcomes. Furthermore, our results suggest that in the Mexican case, models which ignore the potential endogeneity of early-life outcomes are likely to under-estimate the effects of such variables on old-age wealth.

  6. Modeling old-age wealth with endogenous early-life outcomes: The case of Mexico

    PubMed Central

    DeGraff, Deborah S.; Wong, Rebeca

    2014-01-01

    This paper contributes to the literature on the life course and aging by examining the association between early-life outcomes and late-life well being, using data from the Mexican Health and Aging Study. Empirical research in this area has been challenged by the potential endogeneity of the early-life outcomes of interest, an issue which most studies ignore or downplay. Our contribution takes two forms: (1) we examine in detail the potential importance of two key life-cycle outcomes, age at marriage (a measure of family formation) and years of educational attainment (a measure of human capital investment) for old-age wealth, and (2) we illustrate the empirical value of past context variables that could help model the association between early-life outcomes and late-life well being. Our illustrative approach, matching macro-level historical policy and census variables to individual records to use as instruments in modeling the endogeneity of early-life behaviors, yields a statistically identified two-stage model of old-age wealth with minimum bias. We use simulations to show that the results for the model of wealth in old age are meaningfully different when comparing the approach that accounts for endogeneity with an approach that assumes exogeneity of early-life outcomes. Furthermore, our results suggest that in the Mexican case, models which ignore the potential endogeneity of early-life outcomes are likely to under-estimate the effects of such variables on old-age wealth. PMID:25170434

  7. Effects of thermal aging on fracture toughness and Charpy-impact strength of stainless steel pipe welds

    SciTech Connect

    Gavenda, D.J.; Michaud, W.F.; Galvin, T.M.; Burke, W.F.; Chopra, O.K.

    1996-05-01

    Degradation of fracture toughness, tensile, and Charpy-impact properties of Type 304 and 304/308 SS pipe welds due to thermal aging was studied at room temperature and 290 C. Thermal aging of SS welds results in moderate decreases in charpy-impact strength and fracture toughness. Upper-shelf energy decreased by 50-80 J/cm{sup 2}. Decrease in fracture toughness J-R curve or J{sub IC} is relatively small. Thermal aging had no or little effect on tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds.

  8. Effects of thermal aging on fracture toughness and charpy-impact strength of stainless steel pipe welds.

    SciTech Connect

    Gavenda, D. J.; Michaud, W. F.; Galvin, T. M.; Burke, W. F.; Chopra, O. K.; Energy Technology

    1996-06-05

    The degradation of fracture toughness, tensile, and Charpy-impact properties of Type 308 stainless steel (SS) pipe welds due to thermal aging has been characterized at room temperature and 290 C. Thermal aging of SS welds results in moderate decreases in Charpy-impact strength and fracture toughness. For the various welds in this study, upper-shelf energy decreased by 50-80 J/cm{sup 2}. The decrease in fracture toughness J-R curve or JIC is relatively small. Thermal aging had little or no effect on the tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by the formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on the fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds.

  9. The Concepts and Consequences of Early Ovarian Ageing: A Caveat to Women's Health

    PubMed Central

    Subrat, Panda; Santa, Singh A.; Vandana, Jha

    2013-01-01

    Apparent rise in the incidence of infertility in females and the trend shifting towards delayed child bearing brought up the concept of ovarian ageing. Women in their early thirties show poor ovarian reserve which is an entity named as early ovarian ageing. Early ovarian ageing is mostly genetically determined, but acquired modifiable factors like smoking, or ovarian surgery have some roles. Infertility and subfertility are the only clinical recognizable sequelae in the early ovarian ageing. The worrisome fact is that the outcome of assisted reproductive techniques is also not that much encouraging. Even if ovarian priming with DHEA has raised hope in the assisted reproductive techniques for these patients, but more randomized trials are needed to support this. Screening of these women with antimullerian hormone, antral follicle count and genetic analysis may be useful for recommendation at appropriate biological time regarding conception or fertility preservation. PMID:23926554

  10. [Bladder cancer at an early age in father and son].

    PubMed

    Ovsiannikov, D; Stöhr, R; Hartmann, A; Böttrich, R; Hengstler, J G; Golka, K

    2011-12-01

    Bladder cancer may be caused by external factors like tobacco smoking, but may also be familial. We report on a father and son who developed this tumour at the ages of 45 and 35. Testing various genetic markers including the mismatch repair proteins MLH1, MSH2 and MSH6, whose loss is associated with a higher risk for hereditary non-polyposis colorectal cancer (HNPCC, Lynch syndrome), did not point to a familial disease. Thus the heavy smoking habits of the two patients must be considered as causal.

  11. Can Quantitative Muscle Strength and Functional Motor Ability Differentiate the Influence of Age and Corticosteroids in Ambulatory Boys with Duchenne Muscular Dystrophy?

    PubMed Central

    Buckon, Cathleen; Sienko, Susan; Bagley, Anita; Sison-Williamson, Mitell; Fowler, Eileen; Staudt, Loretta; Heberer, Kent; McDonald, Craig M.; Sussman, Michael

    2016-01-01

    Background: In the absence of a curative treatment for Duchenne Muscular Dystrophy (DMD), corticosteroid therapy (prednisone, deflazacort) has been adopted as the standard of care, as it slows the progression of muscle weakness and enables longer retention of functional mobility. The ongoing development of novel pharmacological agents that target the genetic defect underlying DMD offer hope for a significant alteration in disease progression; however, substantiation of therapeutic efficacy has proved challenging. Identifying functional outcomes sensitive to the early, subtle changes in muscle function has confounded clinical trials. Additionally, the alterations in disease progression secondary to corticosteroid therapy are not well described making it difficult to ascertain the benefits of novel agents, often taken concurrently with corticosteroids. Objective: The purpose of this study was to examine outcome responsiveness to corticosteroid therapy and age at the onset of a natural history study of ambulatory boys with DMD. Methods: Eighty-five ambulatory boys with DMD (mean age 93 mo, range 49 to 180 mo) were recruited into this study. Fifty participants were on corticosteroid therapy, while 33 were corticosteroid naïve at the baseline assessment. Within each treatment group boys were divided in two age groups, 4 to 7 years and 8 and greater years of age. The Biodex System 3 Pro isokinetic dynamometer was used to assess muscle strength. Motor skills were assessed using the upper two dimensions (standing/walking, running & jumping) of the Gross Motor Function Measure (GMFM 88) and Timed Motor Tests (TMTs) (10-meter run, sit to stand, supine to stand, climb 4-stairs). Two way analysis of variance and Pearson correlations were used for analysis. Results: A main effect for age was seen in select lower extremity muscle groups (hip flexors, knee extensors and ankle dorsiflexors), standing dimension skills, and all TMTs with significantly greater weakness and loss of

  12. Early and Late Talkers: School-Age Language, Literacy and Neurolinguistic Differences

    ERIC Educational Resources Information Center

    Preston, Jonathan L.; Frost, Stephen J.; Mencl, William Einar; Fulbright, Robert K.; Landi, Nicole; Grigorenko, Elena; Jacobsen, Leslie; Pugh, Kenneth R.

    2010-01-01

    Early language development sets the stage for a lifetime of competence in language and literacy. However, the neural mechanisms associated with the relative advantages of early communication success, or the disadvantages of having delayed language development, are not well explored. In this study, 174 elementary school-age children whose parents…

  13. Early Math Trajectories: Low-Income Children's Mathematics Knowledge from Age 4 to 11

    ERIC Educational Resources Information Center

    Rittle-Johnson, Bethany; Fyfe, Emily R.; Hofer, Kerry G.; Farran, Dale C.

    2016-01-01

    Early mathematics knowledge is a strong predictor of later academic achievement, but children from low-income families enter school with weak mathematics knowledge. An Early Math Trajectories model is proposed and evaluated within a longitudinal study of 517 low-income American children from age 4 to 11. This model includes a broad range of math…

  14. The Foundations of a Developmental Early Childhood Program for Children, Ages 2 1/2-6.

    ERIC Educational Resources Information Center

    Child Day Care Association of St. Louis, MO.

    Compiled are three related sets of materials: (1) a discussion of the foundations of a developmental early childhood program for children between 2 1/2 and 6 years of age; (2) guidelines for planning activity areas and providing equipment for children in the early childhood program; and (3) an inventory with approximate prices of equipment and…

  15. An Experimental Study of Early L3 Development: Age, Bilingualism and Classroom Exposure

    ERIC Educational Resources Information Center

    Stafford, Catherine A.; Sanz, Cristina; Bowden, Harriet Wood

    2010-01-01

    This research investigated Spanish-English bilingual adults' initial learning of a third language (L3), Latin, comparing the learning processes and outcomes of early- and late-onset bilinguals. Thirty-three participants were classified as Early or Late Bilinguals according to their age of arrival to the USA, and they were introduced to Latin by…

  16. Bayesian Ages for Early-type Stars from Isochrones Including Rotation, and a Possible Old Age for the Hyades

    NASA Astrophysics Data System (ADS)

    Brandt, Timothy D.; Huang, Chelsea X.

    2015-07-01

    We combine recently computed models of stellar evolution using a new treatment of rotation with a Bayesian statistical framework to constrain the ages and other properties of early-type stars. We find good agreement for early-type stars and clusters with known young ages, including β Pictoris, the Pleiades, and the Ursa Majoris moving group. However, we derive a substantially older age for the Hyades open cluster (750 ± 100 Myr compared to 625 ± 50 Myr). This older age results from both the increase in main-sequence lifetime with stellar rotation and from the fact that rotating models near the main-sequence turnoff are more luminous, overlapping with slightly more massive (and shorter-lived) nonrotating ones. Our method uses a large grid of nonrotating models to interpolate between a much sparser rotating grid, and also includes a detailed calculation of synthetic magnitudes as a function of orientation. We provide a web interface at http://www.bayesianstellarparameters.info, where the results of our analysis may be downloaded for individual early-type (B-V≲ 0.25) Hipparcos stars. The web interface accepts user-supplied parameters for a Gaussian metallicity prior and returns posterior probability distributions on mass, age, and orientation.

  17. Age-related changes in bone-strength-associated geometry indices in naive human population.

    PubMed

    Kalichman, Leonid; Malkin, Ida; Bigman, Galya; Matias, Rakefet; Seibel, Markus J; Kobyliansky, Eugene; Livshits, Gregory

    2008-07-01

    The aim of the present study was to evaluate age- and sex-related changes in the geometry parameters (metacarpal cortical index (MCI) and Breaking Bending Resistance Index [BBRI]) of long hand bones in a large Chuvashian cohort using cross-sectional and longitudinal study designs. The data were gathered in 1994 (557 individuals) and 2002 (513 individuals). The latter sample included 260 individuals who were studied only during the second expedition, and 253 individuals who were previously investigated in 1994. Statistical analyses included a maximum likelihood-based model-fitting technique and a t-test comparison. Our study describes age-related MCI and BBRI changes in both sexes from the age of 18 years to 84 years. At any age, the BBRI values were higher in males than in females, but MCI was greater in females than in males before age 50 and lower after that age. The study provides initial evidence of a secular trend in MCI and BBRI. In male hand bones, the cortex became relatively thicker and it better resisted bending and breaking in comparison to individuals born at the beginning of the 20th century. In females, the trend toward higher MCI values can be observed only in those born between 1936 and 1966 and the trend toward higher BBRI values stopped in 1950.

  18. The Early Iron Age of the Mössbauer Era

    NASA Astrophysics Data System (ADS)

    Hanna, Stanley S.

    This account of the early days of Mössbauer spectroscopy in the United States was delivered by Stanley S. Hanna at the International Conference on the Mössbauer Effect 1989 in Vancouver, BC, Canada. It is one of a series of invited talks discussing the history and some newer developments of Mössbauer studies. They all appeared in Hyperfine Interactions 90 (1990). Stanley's narrative gives a vivid account of the struggle to understand the hyperfine spectrum of iron, which nowadays is often just an experiment a physics major has to carry out in the physics lab course. With the permission of the author, one of the editors (GMK) has made a few alterations and abridgments to adjust this text to the present volume. GMK came to Argonne Nat'l. Lab. at a much later time than the one described in this article. But he got to know personally most of the actors of the wild time recounted here, and also was told their personal experiences. GMK also had the good fortune to work with Stanley Hanna and his (then) graduate student Gene Sprouse at Stanford.

  19. My Entirely Plausible Fantasy: Early Mathematics Education in the Age of the Touchscreen Computer

    ERIC Educational Resources Information Center

    Ginsburg, Herbert P.

    2014-01-01

    This paper offers an account of what early mathematics education could look like in an age of young digital natives. Each "Tubby," as the tablets are called, presents Nicole (our generic little child) with stimulating mathematics microworlds, from which, beginning at age 3, she can learn basic math concepts, as well as methods of…

  20. Mixed-Age Grouping in Early Childhood--Creating the Outdoor Learning Environment

    ERIC Educational Resources Information Center

    Rouse, Elizabeth

    2015-01-01

    Children attending centre-based early childhood care and education programmes across Australia are most likely to be grouped according to age and development. While multi- or mixed-age grouping has been seen to have positive benefits on young children's learning and pro-social behaviours, this approach is not usually adopted in the organisation of…

  1. Early Enrollees and Peer Age Effect: First Evidence from INVALSI Data

    ERIC Educational Resources Information Center

    Ordine, Patrizia; Rose, Giuseppe; Sposato, Daniela

    2015-01-01

    This paper estimates peer age effect on educational outcomes of Italian pupils attending primary school by exploiting changes in enrollment rules over the last few years. The empirical procedure allows to understand if there is selection in classroom formation, arguing that in the absence of pupils sorting by early age at school entry, it is…

  2. Working Memory in Early-School-Age Children with Asperger's Syndrome

    ERIC Educational Resources Information Center

    Cui, Jifang; Gao, Dingguo; Chen, Yinghe; Zou, Xiaobing; Wang, Ya

    2010-01-01

    Using a battery of working memory span tasks and n-back tasks, this study aimed to explore working memory functions in early-school-age children with Asperger's syndrome (AS). Twelve children with AS and 29 healthy children matched on age and IQ were recruited. Results showed: (a) children with AS performed better in digit and word recall tasks,…

  3. Rejuvenation of the muscle stem cell population restores strength to injured aged muscles.

    PubMed

    Cosgrove, Benjamin D; Gilbert, Penney M; Porpiglia, Ermelinda; Mourkioti, Foteini; Lee, Steven P; Corbel, Stephane Y; Llewellyn, Michael E; Delp, Scott L; Blau, Helen M

    2014-03-01

    The elderly often suffer from progressive muscle weakness and regenerative failure. We demonstrate that muscle regeneration is impaired with aging owing in part to a cell-autonomous functional decline in skeletal muscle stem cells (MuSCs). Two-thirds of MuSCs from aged mice are intrinsically defective relative to MuSCs from young mice, with reduced capacity to repair myofibers and repopulate the stem cell reservoir in vivo following transplantation. This deficiency is correlated with a higher incidence of cells that express senescence markers and is due to elevated activity of the p38α and p38β mitogen-activated kinase pathway. We show that these limitations cannot be overcome by transplantation into the microenvironment of young recipient muscles. In contrast, subjecting the MuSC population from aged mice to transient inhibition of p38α and p38β in conjunction with culture on soft hydrogel substrates rapidly expands the residual functional MuSC population from aged mice, rejuvenating its potential for regeneration and serial transplantation as well as strengthening of damaged muscles of aged mice. These findings reveal a synergy between biophysical and biochemical cues that provides a paradigm for a localized autologous muscle stem cell therapy for the elderly.

  4. Effect of regular swimming exercise on the physical composition, strength, and blood lipid of middle-aged women

    PubMed Central

    Lee, Bo-Ae; Oh, Deuk-Ja

    2015-01-01

    The purpose of this study is to define the effects of regular swimming exercise on the physical composition, physical strength, and blood lipids of middle-aged women. The subjects of this study are a total of 24 middle-aged women in the swimming group and the control group, with 12 women for each group. The swimming group performed swimming exercise for 60 min every time for 3 times a week, for a total of 12 weeks. For data processing, SPSS 21.0 statistics program was used to calculate the mean and standard deviation. For the difference verification on the change in mean for each group and between the groups, paired and independent t-tests were respectively used. As a result, for physical composition, the body fat rate decreased in the swimming group. Moreover, the difference verification result showed a statistically significant difference between the groups. For physical strength, the difference verification result for each group showed that the swimming group had a statistically significant difference in flexibility and cardiovascular endurance. Moreover, the difference verification result between the groups showed a statistically significant difference only for flexibility. For blood lipids, as a result of the difference verification for each group, T-C and TG showed a significant decrease, and HDL-C, a significant increase. However, in the difference verification result between the groups, only T-C and TG showed a statistically significant difference. With these results, it is considered that regular swimming exercise is effective for improving the physical composition, physical strength, and blood lipids of middle-aged women. PMID:26535217

  5. Perceptions of Competence, Strength, and Age Influence Voters to Select Leaders with Lower-Pitched Voices.

    PubMed

    Klofstad, Casey A; Anderson, Rindy C; Nowicki, Stephen

    2015-01-01

    Voters prefer leaders with lower-pitched voices because they are perceived as stronger, having greater physical prowess, more competent, and having greater integrity. An alternative hypothesis that has yet to be tested is that lower-pitched voices are perceived as older and thus wiser and more experienced. Here the relationships between candidate voice pitch, candidate age, and electoral success are examined with two experiments. Study 1 tests whether voters discriminate on candidate age. The results show that male and female candidates in their 40s and 50s, the time in the lifecycle when voice pitch is at its lowest, are preferred over candidates in their 30s, 60s, and 70s. Study 2 shows that the preference for leaders with lower-pitched voices correlates with the perception that speakers with lower voices are stronger, more competent, and older, but the influence of perception of age on vote choice is the weakest of the three. PMID:26252894

  6. Perceptions of Competence, Strength, and Age Influence Voters to Select Leaders with Lower-Pitched Voices.

    PubMed

    Klofstad, Casey A; Anderson, Rindy C; Nowicki, Stephen

    2015-01-01

    Voters prefer leaders with lower-pitched voices because they are perceived as stronger, having greater physical prowess, more competent, and having greater integrity. An alternative hypothesis that has yet to be tested is that lower-pitched voices are perceived as older and thus wiser and more experienced. Here the relationships between candidate voice pitch, candidate age, and electoral success are examined with two experiments. Study 1 tests whether voters discriminate on candidate age. The results show that male and female candidates in their 40s and 50s, the time in the lifecycle when voice pitch is at its lowest, are preferred over candidates in their 30s, 60s, and 70s. Study 2 shows that the preference for leaders with lower-pitched voices correlates with the perception that speakers with lower voices are stronger, more competent, and older, but the influence of perception of age on vote choice is the weakest of the three.

  7. Perceptions of Competence, Strength, and Age Influence Voters to Select Leaders with Lower-Pitched Voices

    PubMed Central

    Klofstad, Casey A.; Anderson, Rindy C.; Nowicki, Stephen

    2015-01-01

    Voters prefer leaders with lower-pitched voices because they are perceived as stronger, having greater physical prowess, more competent, and having greater integrity. An alternative hypothesis that has yet to be tested is that lower-pitched voices are perceived as older and thus wiser and more experienced. Here the relationships between candidate voice pitch, candidate age, and electoral success are examined with two experiments. Study 1 tests whether voters discriminate on candidate age. The results show that male and female candidates in their 40s and 50s, the time in the lifecycle when voice pitch is at its lowest, are preferred over candidates in their 30s, 60s, and 70s. Study 2 shows that the preference for leaders with lower-pitched voices correlates with the perception that speakers with lower voices are stronger, more competent, and older, but the influence of perception of age on vote choice is the weakest of the three. PMID:26252894

  8. Early Characteristics of Children with ASD Who Demonstrate Optimal Progress Between Age Two and Four.

    PubMed

    Moulton, Emily; Barton, Marianne; Robins, Diana L; Abrams, Danielle N; Fein, Deborah

    2016-06-01

    Although for many children, Autism Spectrum Disorder (ASD) is a lifelong disability, a subset of children with ASD lose their diagnosis and show typical cognitive and adaptive abilities. The ages at which this transition can occur is not known, but it sometimes occurs quite early. Participants in the current study were 207 children with an ASD at age two who were reevaluated at age four. Eighty-three percent retained an ASD diagnosis at reevaluation and 9 % showed "optimal progress": clear ASD at age two but not at age four, and average cognition, language, communication and social skills at age four. Early child-level factors predicted optimal progress: diagnosis of PDD-NOS, fewer repetitive behaviors, less severe symptomatology and stronger adaptive skills.

  9. Effect of resin cement, aging process and root level on the bond strength of the resin-fiber posts

    NASA Astrophysics Data System (ADS)

    Almuhim, Khalid Salman

    Background. Little is known about the long-term clinical bonding effectiveness of the Fiber-reinforced composite (FRC) posts cemented with self-etch adhesive systems. Bond stability and longevity of the cemented post are adversely affected by physical and chemical factors over time, such as expansion and contraction stresses caused by thermal changes and occlusal load. This clinical condition can be simulated in vitro by thermocyclic loading; and bonding effectiveness can be evaluated by applying the micropush out test. Therefore, more in vitro studies are needed to evaluate the bond strength of the fiber posts cemented with different resin cement systems after simulating the artificial aging induced by thermocycling. The aim of this study was to compare the microtensile bond strength of two different resin cement systems (total etch, and self-etch resin cement system) used for cementation of fiber reinforced composite posts in three different aging periods using thermocycling. Methods. Following IRB approval, sixty freshly extracted bicuspid single rooted natural teeth were endodontically treated, and the post-spaces were prepared to receive a fiber-post cemented with either a total etch resin cement (Rely-X Ultimate) or with a self-etch resin cement (Rely-X Unicem). No thermocycling, 20,000 and 40,000 cycles was used to age the specimens. Teeth were randomly allocated into six different groups: G1 - Control: Rely-X Ultimate cement with no thermocycling. G2: Rely-X Ultimate cement with 20,000 thermocycling. G3: Rely-X Ultimate cement with 40,000 thermocycling. G4: Rely-X Unicem cement. G5: Rely-X Unicem cement. G6: Rely-X Unicem cement. Microtensile bond strength determined using a micropush out test on a universal testing machine (MTS). Additionally, the failure mode of each specimen was observed under a stereomicroscope (Olympus) at 40x magnification. Finally, one representative sample was randomly selected from each of the five failure modes for scanning

  10. Effect of aging with partial discharges on the remnant breakdown strength of polypropylene films with natural and synthetic nanofillers

    NASA Astrophysics Data System (ADS)

    Rab, Md. A.; Dhara, Rohitha; Basappa, Prathap; Poda, Anil B.

    2014-08-01

    Uniform dispersion of small amounts of nanofillers into Polypropylene (PP) base polymer have shown to improve the dielectric properties such as Partial Discharge (PD) resistance and breakdown strength (BDS). A comparative analyses of the effect of addition of natural and synthetic nanofillers on the PD characteristics and the BDS prior to and after aging with PD have been performed. Results indicate that addition of both type of fillers significantly reduce maximum PD magnitude (Qmax). The Weibull characteristic BDS magnitudes were observed to improve with addition of nanofillers.

  11. A case of amnesia at an early age.

    PubMed

    Brizzolara, Daniela; Casalini, Claudia; Montanaro, Domenico; Posteraro, Federico

    2003-01-01

    A dissociation between short- and long-term memory (LTM) and between the episodic and the semantic component of LTM is reported in a young girl who became amnesic at the age of 6 after an episode of acute encephalopathy resulting in bilateral frontal, insular, thalamic, ponto-mesencephalic, hippocampal and temporal lesions, as documented by MRI. The girl became amnesic a few months after starting school. A follow-up investigation showed that she was able to learn to read, write and acquire number facts and procedures and to improve her semantic knowledge. Our results show that the features of adult amnesia can also be found in children and that new semantic knowledge can be acquired in spite of an anterograde memory deficit. This dissociation does not agree with theories viewing long-term declarative memory as a unitary process mediated by the hippocampal system, but supports recent hypotheses that the acquisition of semantic knowledge is independent from episodic memory processes, and takes place through spared cortical regions subjacent to the hippocampi (Vargha-Khadem et al., 1997).

  12. A case of amnesia at an early age.

    PubMed

    Brizzolara, Daniela; Casalini, Claudia; Montanaro, Domenico; Posteraro, Federico

    2003-01-01

    A dissociation between short- and long-term memory (LTM) and between the episodic and the semantic component of LTM is reported in a young girl who became amnesic at the age of 6 after an episode of acute encephalopathy resulting in bilateral frontal, insular, thalamic, ponto-mesencephalic, hippocampal and temporal lesions, as documented by MRI. The girl became amnesic a few months after starting school. A follow-up investigation showed that she was able to learn to read, write and acquire number facts and procedures and to improve her semantic knowledge. Our results show that the features of adult amnesia can also be found in children and that new semantic knowledge can be acquired in spite of an anterograde memory deficit. This dissociation does not agree with theories viewing long-term declarative memory as a unitary process mediated by the hippocampal system, but supports recent hypotheses that the acquisition of semantic knowledge is independent from episodic memory processes, and takes place through spared cortical regions subjacent to the hippocampi (Vargha-Khadem et al., 1997). PMID:14584545

  13. Confirmation of a late Oligocene-early Miocene age of the Deseadan Salla Beds of Bolivia

    SciTech Connect

    Naeser, C.W.; McKee, E.H.; Johnson, N.M.; MacFadden, B.J.

    1987-11-01

    Three new fission-track (zircon) and four new K-Ar (biotite) dates corroborate a late Oligocene-early Miocene age (22-28 Ma) for the Salla Beds of Bolivia. These ages contrast markedly with the previously accepted age of about 35 Ma for these strata and their contained faunas, and recasts of order and chronology of interchange between New World and Old World mammals.

  14. Confirmation of a late Oligocene-early Miocene age of the Deseadan Salla Beds of Bolivia.

    USGS Publications Warehouse

    Naeser, C.W.; McKee, E.H.; Johnson, N.M.; Macfadden, B.J.

    1987-01-01

    Three new fission-track (zircon) and four new K-Ar (biotite) dates corroborate a late Oligocene-early Miocene age (22-28 Ma) for the Salla Beds of Bolivia. These ages contrast markedly with the previously accepted age of about 35 Ma for these strata and their contained faunas, and recasts of order and chronology of interchange between New World and Old World mammals. -Authors

  15. The influence of age, muscle strength and speed of information processing on recovery responses to external perturbations in gait.

    PubMed

    Senden, R; Savelberg, H H C M; Adam, J; Grimm, B; Heyligers, I C; Meijer, K

    2014-01-01

    Dynamic imbalance caused by external perturbations to gait can successfully be counteracted by adequate recovery responses. The current study investigated how the recovery response is moderated by age, walking speed, muscle strength and speed of information processing. The gait pattern of 50 young and 45 elderly subjects was repeatedly perturbed at 20% and 80% of the first half of the swing phase using the Timed Rapid impact Perturbation (TRiP) set-up. Recovery responses were identified using 2D cameras. Muscular factors (dynamometer) and speed of information processing parameters (computer-based reaction time task) were determined. The stronger, faster reacting and faster walking young subjects recovered more often by an elevating strategy than elderly subjects. Twenty three per cent of the differences in recovery responses were explained by a combination of walking speed (B=-13.85), reaction time (B=-0.82), maximum extension strength (B=0.01) and rate of extension moment development (B=0.19). The recovery response that subjects employed when gait was perturbed by the TRiP set-up was modified by several factors; the individual contribution of walking speed, muscle strength and speed of information processing was small. Insight into remaining modifying factors is needed to assist and optimise fall prevention programmes.

  16. The Predictive Utility of Early Childhood Disruptive Behaviors for School-Age Social Functioning

    PubMed Central

    Shaw, Daniel S.; Dishion, Thomas J.; Wilson, Melvin N.

    2016-01-01

    Research suggests that school-age children with disruptive behavior (DB) problems frequently demonstrate impaired social skills and experience rejection from peers, which plays a crucial role in the pathway to more serious antisocial behavior. A critical question is which DB problems in early childhood are prognostic of impaired social functioning in school-age children. This study examines the hypothesis that aggression in early childhood will be the more consistent predictor of compromised social functioning than inattentive, hyperactive-impulsive, or oppositional behavior. Participants included an ethnically diverse sample of 725 high-risk children from 3 geographically distinct areas followed from ages 2 to 8.5. Four latent growth models of DB from child ages 2 to 5, and potential interactions between dimensions, were used to predict latent parent and teacher ratings of school-age social dysfunction. Analyses were conducted in a multi-group format to examine potential differences between intervention and control group participants. Results showed that age 2 aggression was the DB problem most consistently associated with both parent- and teacher-rated social dysfunction for both groups. Early starting aggressive behavior may be particularly important for the early identification of children at risk for school-age social difficulties. PMID:25526865

  17. Plate tectonics on the early Earth: Limitations imposed by strength and buoyancy of subducted lithosphere

    NASA Astrophysics Data System (ADS)

    van Hunen, Jeroen; van den Berg, Arie P.

    2008-06-01

    The tectonic style and viability of modern plate tectonics in the early Earth is still debated. Field observations and theoretical arguments both in favor and against the uniformitarian view of plate tectonics back until the Archean continue to accumulate. Here, we present the first numerical modeling results that address for a hotter Earth the viability of subduction, one of the main requirements for plate tectonics. A hotter mantle has mainly two effects: 1) viscosity is lower, and 2) more melt is produced, which in a plate tectonic setting will lead to a thicker oceanic crust and harzburgite layer. Although compositional buoyancy resulting from these thick crust and harzburgite might be a serious limitation for subduction initiation, our modeling results show that eclogitization significantly relaxes this limitation for a developed, ongoing subduction process. Furthermore, the lower viscosity leads to more frequent slab breakoff, and sometimes to crustal separation from the mantle lithosphere. Unlike earlier propositions, not compositional buoyancy considerations, but this lithospheric weakness could be the principle limitation to the viability of plate tectonics in a hotter Earth. These results suggest a new explanation for the absence of ultrahigh-pressure metamorphism (UHPM) and blueschists in most of the Precambrian: early slabs were not too buoyant, but too weak to provide a mechanism for UHPM and exhumation.

  18. Effects of age and muscle action type on acute strength and power recovery following fatigue of the leg flexors.

    PubMed

    Thompson, Brennan J; Conchola, Eric C; Stock, Matt S

    2015-12-01

    Short-term strength and power recovery patterns following fatigue have received little research attention, particularly as they pertain to age-specific responses, and the leg flexors (i.e., hamstrings) muscle group. Thus, research is warranted addressing these issues because both age-related alterations in the neuromuscular system and mode of muscle action (e.g., eccentric, concentric, isometric) may differentially influence recovery responses from fatigue. The aim of this study was to investigate the strength and power recovery responses for eccentric, concentric, and isometric muscle actions of the leg flexors in young and older men following an isometric, intermittent fatigue-inducing protocol. Nineteen young (age = 25 ± 3 years) and nineteen older (71 ± 4) men performed maximal voluntary contractions (MVCs) for eccentric, concentric, and isometric muscle actions followed by a fatigue protocol of intermittent (0.6 duty cycle) isometric contractions of the leg flexors at 60% of isometric MVC. MVCs of each muscle action were performed at 0, 7, 15, and 30 min following fatigue. Peak torque (PT) and mean power values were calculated from the MVCs and the eccentric/concentric ratio (ECR) was derived. For PT and mean power, young men showed incomplete recovery at all time phases, whereas the older men had recovered by 7 min. Eccentric and isometric muscle actions showed incomplete recovery at all time phases, but concentric recovered by 7 min, independent of age. The ECR was depressed for up to 30 min following fatigue. More rapid and pronounced recovery in older men and concentric contractions may be related to physiological differences specific to aging and muscle action motor unit patterns. Individuals and clinicians may use these time course responses as a guide for recovery following activity-induced fatigue.

  19. The relationship between early ego strength and adolescent responses to the threat of nuclear war

    SciTech Connect

    Andrekus, N.J.

    1989-01-01

    Ego resiliency and ego control, measured when subjects were 3 or 4 years old, were related to expectation of war, concern for the future, and activism in response to the threat of nuclear war, measured when subjects were 18 years old. Data from 92 participants in a longitudinal study of ego and cognitive development conducted by Jeanne and Jack Block at the University of California, Berkeley were used to test hypotheses. Assessments with the California Child Q-set, composited across multiple independent observers, provide measures of ego resiliency and ego control. Adolescent interviews regarding the perception of likelihood of nuclear war, how this affects their future, and their antinuclear and general political activism were scaled and rated. Early ego resiliency and ego under control were hypothesized to account for the variance in adolescent nuclear responses and activism. The only significant longitudinal relationships were in the female sample, where ego under control was found to be a significant predictor of both general political activism (p<.01) and ideas of the future being affected by the nuclear threat (p<.05). Among males, the relationship between early ego resiliency and adolescent antinuclear activism approached significance (p<.10). Adolescent personality was significantly related to several measures of nuclear response. In girls, adolescent ego under control related to perception of likelihood of nuclear war (p<.05) and antinuclear activism (p<.05), and the interaction of ego resiliency and ego under control predicted general political activism (p<.0005). In boys, adolescent ego resiliency correlated with antinuclear activism (p<.05). These findings were discussed in terms of antecedent parenting styles, and conceptual links were drawn between children's ego resiliency and security of attachment, perspective taking, and moral development.

  20. Behavioural early-life exposures and body composition at age 15 years

    PubMed Central

    Leary, S D; Lawlor, D A; Davey Smith, G; Brion, M J; Ness, A R

    2015-01-01

    Background/Objectives: Previous studies have demonstrated associations between some early-life exposures and later obesity, but most have used body mass index in childhood or adulthood as the outcome. The objective of this study was to investigate whether early-life exposures were associated with directly measured fat and lean mass in adolescence. Subjects/Methods: This study used data on 4750 mother–offspring pairs, collected as a part of the Avon Longitudinal Study of Parents and Children, Bristol, UK between 1991 and 1992; associations between behavioural exposures occurring from conception up to 5 years of age (maternal and paternal smoking during pregnancy, breastfeeding, age at introduction to solids, dietary patterns and physical inactivity during early childhood) and offspring body composition measured by dual-energy X-ray absorptiometry at ~15 years were assessed. Results: After full adjustment for potential confounders, maternal smoking during pregnancy, having a junk food diet and spending more time watching television in early childhood were all associated with higher fat mass at age 15, whereas maternal smoking, having a healthy diet and playing computer games more frequently in early childhood were all associated with a higher lean mass at age 15. Associations with paternal smoking were generally weaker for both fat and lean mass, but as there was no strong statistical evidence for maternal vs paternal differences, confounding by social factors rather than a direct effect of maternal smoking cannot be ruled out. Early feeding was not associated with fat or lean mass at age 15. Conclusions: This study does not provide compelling evidence for associations between most early-life factors and body composition in adolescence. However, possible associations with dietary patterns and physical inactivity in early childhood require further investigation in other cohorts that have direct measurements of adolescent body composition. PMID:25664839

  1. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating.

    PubMed

    Stockhammer, Philipp W; Massy, Ken; Knipper, Corina; Friedrich, Ronny; Kromer, Bernd; Lindauer, Susanne; Radosavljević, Jelena; Wittenborn, Fabian; Krause, Johannes

    2015-01-01

    The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2), which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2) around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria) and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz) A1 and Bronze (Bz) A2, but a complete overlap between the type objects of the two phases from 1900-1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology.

  2. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating

    PubMed Central

    Knipper, Corina; Friedrich, Ronny; Kromer, Bernd; Lindauer, Susanne; Radosavljević, Jelena; Wittenborn, Fabian; Krause, Johannes

    2015-01-01

    The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2), which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2) around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria) and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz) A1 and Bronze (Bz) A2, but a complete overlap between the type objects of the two phases from 1900–1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology. PMID:26488413

  3. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating.

    PubMed

    Stockhammer, Philipp W; Massy, Ken; Knipper, Corina; Friedrich, Ronny; Kromer, Bernd; Lindauer, Susanne; Radosavljević, Jelena; Wittenborn, Fabian; Krause, Johannes

    2015-01-01

    The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2), which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2) around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria) and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz) A1 and Bronze (Bz) A2, but a complete overlap between the type objects of the two phases from 1900-1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology. PMID:26488413

  4. INEQUITY ISSUES AND MOTHERS' PREGNANCY, DELIVERY AND EARLY-AGE SURVIVAL EXPERIENCES IN ENDE DISTRICT, INDONESIA.

    PubMed

    Pardosi, Jerico Franciscus; Parr, Nick; Muhidin, Salut

    2015-11-01

    Indonesia's infant mortality rates are among the highest in South-East Asia, and there are substantial variations between its sub-national regions. This qualitative study aims to explore early mortality-related health service provision and gender inequity issues based on mothers' pregnancy, delivery and early-age survival experience in Ende district, Nusa Tenggara Timur province. Thirty-two mothers aged 18-45 years with at least one birth in the previous five years were interviewed in depth in May 2013. The results show most mothers have little knowledge about the danger signs for a child's illness. Mothers with early-age deaths generally did not know the cause of death. Very few mothers had received adequate information on maternal and child health during their antenatal and postnatal visits to the health facility. Some mothers expressed a preference for using a traditional birth attendant, because of their ready availability and the more extensive range of support services they provide, compared with local midwives. Unprofessional attitudes displayed by midwives were reported by several mothers. As elsewhere in Indonesia, the power of health decision-making lies with the husband. Policies aimed at elevating mothers' roles in health care decision-making are discussed as measures that would help to improve early-age survival outcomes. Widening the public health insurance distribution, especially among poorer mothers, and equalizing the geographical distribution of midwives and health facilities are recommended to tackle geographical inequities and to increase early-age survival in Ende district. PMID:25499196

  5. Early-late life trade-offs and the evolution of ageing in the wild.

    PubMed

    Lemaître, Jean-François; Berger, Vérane; Bonenfant, Christophe; Douhard, Mathieu; Gamelon, Marlène; Plard, Floriane; Gaillard, Jean-Michel

    2015-05-01

    Empirical evidence for declines in fitness components (survival and reproductive performance) with age has recently accumulated in wild populations, highlighting that the process of senescence is nearly ubiquitous in the living world. Senescence patterns are highly variable among species and current evolutionary theories of ageing propose that such variation can be accounted for by differences in allocation to growth and reproduction during early life. Here, we compiled 26 studies of free-ranging vertebrate populations that explicitly tested for a trade-off between performance in early and late life. Our review brings overall support for the presence of early-late life trade-offs, suggesting that the limitation of available resources leads individuals to trade somatic maintenance later in life for high allocation to reproduction early in life. We discuss our results in the light of two closely related theories of ageing-the disposable soma and the antagonistic pleiotropy theories-and propose that the principle of energy allocation roots the ageing process in the evolution of life-history strategies. Finally, we outline research topics that should be investigated in future studies, including the importance of natal environmental conditions in the study of trade-offs between early- and late-life performance and the evolution of sex-differences in ageing patterns.

  6. Coercive Family Process and Early-Onset Conduct Problems From Age 2 to School Entry

    PubMed Central

    Smith, Justin D.; Dishion, Thomas J.; Shaw, Daniel S.; Wilson, Melvin N.; Winter, Charlotte C.; Patterson, Gerald R.

    2013-01-01

    The emergence and persistence of conduct problems during early childhood is a robust predictor of behavior problems in school and future maladaptation. In this study we examined the reciprocal influences between observed coercive interactions between children and caregivers, oppositional and aggressive behavior, and growth in parent report of early childhood (ages 2–5) and school-age conduct problems (age 7.5 and 8.5). Participants were drawn from the Early Steps multisite randomized prevention trial that includes an ethnically diverse sample of male and female children and their families (N = 731). A parallel process growth model combining latent trajectory and cross-lagged approaches revealed the amplifying effect of observed coercive caregiver–child interactions on children's noncompliance, whereas child oppositional and aggressive behaviors did not consistently predict increased coercion. The slope and initial levels of child oppositional and aggressive behaviors and the stability of caregiver–child coercion were predictive of teacher-reported oppositional behavior at school age. Families assigned to the Family Check-Up condition had significantly steeper declines in child oppositional and aggressive behavior and moderate reductions in oppositional behavior in school and in coercion at age 3. Results were not moderated by child gender, race/ethnicity, or assignment to the intervention condition. The implications of these findings are discussed with respect to understanding the early development of conduct problems and to designing optimal strategies for reducing problem behavior in early childhood with families most in need. PMID:24690305

  7. Early Impacts on the Moon: Crystallization Ages of Apollo 16 Melt Breccias

    NASA Technical Reports Server (NTRS)

    Norman, M. D.; Shih, C.-Y.; Nyquist, L. E.; Bogard, D. D.; Taylor, L. A.

    2007-01-01

    A better understanding of the early impact history of the terrestrial planets has been identified one of the highest priority science goals for solar system exploration. Crystallization ages of impact melt breccias from the Apollo 16 site in the central nearside lunar highlands show a pronounced clustering of ages from 3.75-3.95 Ga, with several impact events being recognized by the association of textural groups and distinct ages. Here we present new geochemical and petrologic data for Apollo 16 crystalline breccia 67955 that document a much older impact event with an age of 4.2 Ga.

  8. Viking and early Middle Ages northern Scandinavian textiles proven to be made with hemp.

    PubMed

    Skoglund, G; Nockert, M; Holst, B

    2013-01-01

    Nowadays most plant textiles used for clothing and household are made of cotton and viscose. Before the 19th century however, plant textiles were mainly made from locally available raw materials, in Scandinavia these were: nettle, hemp and flax. It is generally believed that in Viking and early Middle Ages Scandinavia hemp was used only for coarse textiles (i.e. rope and sailcloth). Here we present an investigation of 10 Scandinavian plant fibre textiles from the Viking and Early Middle Ages, believed to be locally produced. Up till now they were all believed to be made of flax. We show that 4 textiles, including two pieces of the famous Överhogdal Viking wall-hanging are in fact made with hemp (in three cases hemp and flax are mixed). This indicates that hemp was important, not only for coarse but also for fine textile production in Viking and Early Middle Ages in Scandinavia. PMID:24135914

  9. Viking and Early Middle Ages Northern Scandinavian Textiles Proven to be made with Hemp

    NASA Astrophysics Data System (ADS)

    Skoglund, G.; Nockert, M.; Holst, B.

    2013-10-01

    Nowadays most plant textiles used for clothing and household are made of cotton and viscose. Before the 19th century however, plant textiles were mainly made from locally available raw materials, in Scandinavia these were: nettle, hemp and flax. It is generally believed that in Viking and early Middle Ages Scandinavia hemp was used only for coarse textiles (i.e. rope and sailcloth). Here we present an investigation of 10 Scandinavian plant fibre textiles from the Viking and Early Middle Ages, believed to be locally produced. Up till now they were all believed to be made of flax. We show that 4 textiles, including two pieces of the famous Överhogdal Viking wall-hanging are in fact made with hemp (in three cases hemp and flax are mixed). This indicates that hemp was important, not only for coarse but also for fine textile production in Viking and Early Middle Ages in Scandinavia.

  10. Viking and early Middle Ages northern Scandinavian textiles proven to be made with hemp.

    PubMed

    Skoglund, G; Nockert, M; Holst, B

    2013-10-18

    Nowadays most plant textiles used for clothing and household are made of cotton and viscose. Before the 19th century however, plant textiles were mainly made from locally available raw materials, in Scandinavia these were: nettle, hemp and flax. It is generally believed that in Viking and early Middle Ages Scandinavia hemp was used only for coarse textiles (i.e. rope and sailcloth). Here we present an investigation of 10 Scandinavian plant fibre textiles from the Viking and Early Middle Ages, believed to be locally produced. Up till now they were all believed to be made of flax. We show that 4 textiles, including two pieces of the famous Överhogdal Viking wall-hanging are in fact made with hemp (in three cases hemp and flax are mixed). This indicates that hemp was important, not only for coarse but also for fine textile production in Viking and Early Middle Ages in Scandinavia.

  11. Accurate radiocarbon age estimation using "early" measurements: a new approach to reconstructing the Paleolithic absolute chronology

    NASA Astrophysics Data System (ADS)

    Omori, Takayuki; Sano, Katsuhiro; Yoneda, Minoru

    2014-05-01

    This paper presents new correction approaches for "early" radiocarbon ages to reconstruct the Paleolithic absolute chronology. In order to discuss time-space distribution about the replacement of archaic humans, including Neanderthals in Europe, by the modern humans, a massive data, which covers a wide-area, would be needed. Today, some radiocarbon databases focused on the Paleolithic have been published and used for chronological studies. From a viewpoint of current analytical technology, however, the any database have unreliable results that make interpretation of radiocarbon dates difficult. Most of these unreliable ages had been published in the early days of radiocarbon analysis. In recent years, new analytical methods to determine highly-accurate dates have been developed. Ultrafiltration and ABOx-SC methods, as new sample pretreatments for bone and charcoal respectively, have attracted attention because they could remove imperceptible contaminates and derive reliable accurately ages. In order to evaluate the reliability of "early" data, we investigated the differences and variabilities of radiocarbon ages on different pretreatments, and attempted to develop correction functions for the assessment of the reliability. It can be expected that reliability of the corrected age is increased and the age applied to chronological research together with recent ages. Here, we introduce the methodological frameworks and archaeological applications.

  12. Reproductive investment within inflorescences of Stylidium armeria varies with the strength of early resource commitment

    PubMed Central

    Brookes, Rowan H.; Jesson, Linley K.; Burd, Martin

    2010-01-01

    Background and Aims Resource allocation to flowers, fruits and seeds can vary greatly within an inflorescence. For example, distal fruits are often smaller and produce fewer and smaller fruits and seeds than more basal fruits. To assess the causes and functional significance of intra-inflorescence variation, pollen and resources were manipulated to test whether such patterns could be altered within racemes of Stylidum armeria, a perennial Australian herb. Methods Pollen and resource levels were manipulated over two flowering seasons. How the number of ovules, fertilized ovules and seeds, the probability of fruit set, and the biomass of floral and fruiting structures varied with their position on the raceme were analysed. Key Results Most plants showed a decline in ovule and seed number toward the distal positions on the raceme, but plants differed in their pattern of intra-inflorescence allocation: racemes with greater investment in basal fruits displayed a stronger trade-off with distal investment than did racemes that made smaller initial investments. This trade-off was (a) much stronger for ovule number than for seed number, (b) ameliorated but not erased by resource addition, and (c) exacerbated by resource reduction. There was large and seemingly erratic variation across fruit positions in ovule fertilization and seed set following both natural and supplemental pollination. Conclusions In S. armeria, allocation to reproductive traits within the inflorescence is influenced by dynamic trade-offs in resource allocation between early and late fruits, and may also be subject to inherent architectural effects. Large, unpredictable variation among fruits in fertilization success and seed set may influence the evolution of inflorescence size, ovule number and floral dimorphism. PMID:20375201

  13. Dietary protein intake is associated with maximal and explosive strength of the leg flexors in young and older aged blue collar workers

    PubMed Central

    Thompson, Brennan J.; Ryan, Eric D.; Sobolewski, Eric J.; Smith-Ryan, Abbie E.

    2015-01-01

    The aim of this study was to investigate the association between dietary PRO intake and maximal and rapid strength of the leg flexors in blue collar (BC) working men. Twenty-four young (age=23.2±2.1 yrs), and nineteen older aged (age=52.8±5.2 yrs) men employed in BC occupations completed a three day dietary record and isometric strength testing of the leg flexors. Food logs were analyzed for total protein (TPRO) and essential amino acid (EAA) intake. Rapid and maximal strength capacities were examined from the rate of torque development at 50ms (RTD50) and peak torque (PT) of the torque-time curves, respectively. Pearson correlations and partial correlations were used to examine the relationships between TPRO and EAA intake on strength variables. PT was positively correlated to TPRO and EAA intake in the young (r=0.439 and 0.431;P<0.05) and older aged (r=0.636 and 0.605; P<0.01) men and RTD50 was correlated to TPRO and EAA intake in the young (r=0.512 and 0.310; P=0.01) and older aged (r=0.662 and 0.665; P<0.01) men, respectively. There were no relationships (P>0.05) between TPRO and strength variables when controlling for EAA intake. TPRO intake explained 20–44% of the variance in rapid and maximal strength for both age groups. EAA intake was largely responsible for the positive relationship between PRO intake and strength. Across young and older aged blue collar working male populations, protein consumption was associated with both maximal and explosive strength capacities of the leg flexors muscle group. PMID:25753919

  14. Comparative evaluation of shear bond strengths of veneering porcelain to base metal alloy and zirconia substructures before and after aging – An in vitro study

    PubMed Central

    Sreekala, Laju; Narayanan, Mahesh; Eerali, Sunil M.; Eerali, Susil M.; Varghese, Joju; Zainaba Fathima, A. l.

    2015-01-01

    Objective: The aim of this study was to evaluate and compare the shear bond strength of veneering porcelain to base metal alloy and zirconia substructures before and after aging. Scanning electron microscopy (SEM) was used to determine the failure pattern. Materials and Methods: Twenty rectangular blocks (9 mm length × 4 mm height × 4 mm width) of base metal alloy (Bellabond plus, Bego, Germany) and zirconia (Will ceramZ zirconia K block) were fabricated for shear bond strength test. Surface of the base metal alloy block (4 mm × 4 mm area) was veneered with corresponding veneering porcelain (Ivoclar, IPS classic, vivadent). Similarly, surface of the zirconia rectangular block (4 mm × 4 mm) was veneered with corresponding veneering ceramic (Cercon ceram kiss, Degudent). Out of forty rectangular porcelain veneered core specimen, ten porcelain veneered base metal alloy specimen and ten porcelain veneered zirconia specimen were immersed in water at 37°C for one month to simulate the oral environment. Results: On comparison, the highest shear bond strength value was obtained in porcelain veneered base metal alloy before aging group followed by porcelain veneered base metal alloy after aging group, Porcelain veneered zirconia before aging group, porcelain veneered zirconia after aging group. SEM analysis revealed predominantly cohesive failure of veneering ceramic in all groups. Conclusion: Porcelain veneered base metal alloy samples showed highest shear bond strength than porcelain veneered zirconia samples. Study concluded that aging had an influence on shear bond strength. Shear bond strength was found to be decreasing after aging. SEM analysis revealed cohesive failure of veneering ceramic in all groups suggestive of higher bond strength of the interface than cohesive strength of ceramic. Hence, it was concluded that veneering ceramic was the weakest link. PMID:26942121

  15. Dental enamel hypoplasias and health changes in the Middle Bronze Age - Early Iron Age transition at Pella in Jordan.

    PubMed

    Griffin, R C; Donlon, D

    2007-01-01

    Dental enamel hypoplasias are increasingly being used in epidemiological studies as indicators of health within both modern and prehistoric populations. This symptom of growth disruption is used here to examine possible changes in health occurring at the transition between the Bronze Age and Iron Age in Jordan, through examination of enamel hypoplasias in skeletal remains from two tombs at the archaeological site of Pella. A small but not statistically significant difference in the prevalence and frequency of hypoplastic defects was found between the two time periods. These results suggest that the political and economic changes occurring at this time were not sufficiently stressful to cause a dramatic deterioration in health at the onset of the Early Iron Age. PMID:17582411

  16. Early-late life trade-offs and the evolution of ageing in the wild

    PubMed Central

    Lemaître, Jean-François; Berger, Vérane; Bonenfant, Christophe; Douhard, Mathieu; Gamelon, Marlène; Plard, Floriane; Gaillard, Jean-Michel

    2015-01-01

    Empirical evidence for declines in fitness components (survival and reproductive performance) with age has recently accumulated in wild populations, highlighting that the process of senescence is nearly ubiquitous in the living world. Senescence patterns are highly variable among species and current evolutionary theories of ageing propose that such variation can be accounted for by differences in allocation to growth and reproduction during early life. Here, we compiled 26 studies of free-ranging vertebrate populations that explicitly tested for a trade-off between performance in early and late life. Our review brings overall support for the presence of early-late life trade-offs, suggesting that the limitation of available resources leads individuals to trade somatic maintenance later in life for high allocation to reproduction early in life. We discuss our results in the light of two closely related theories of ageing—the disposable soma and the antagonistic pleiotropy theories—and propose that the principle of energy allocation roots the ageing process in the evolution of life-history strategies. Finally, we outline research topics that should be investigated in future studies, including the importance of natal environmental conditions in the study of trade-offs between early- and late-life performance and the evolution of sex-differences in ageing patterns. PMID:25833848

  17. Early-life conditions and age at first pregnancy in British women.

    PubMed

    Nettle, Daniel; Coall, David A; Dickins, Thomas E

    2011-06-01

    There is growing evidence that the reproductive schedules of female mammals can be affected by conditions experienced during early development, with low parental investment leading to accelerated life-history strategies in the offspring. In humans, the relationships between early-life conditions and timing of puberty are well studied, but much less attention has been paid to reproductive behaviour. Here, we investigate associations between early-life conditions and age at first pregnancy (AFP) in a large, longitudinally studied cohort of British women (n = 4553). Low birthweight for gestational age, short duration of breastfeeding, separation from mother in childhood, frequent family residential moves and lack of paternal involvement are all independently associated with earlier first pregnancy. Apart from that of birthweight, the effects are robust to adjustment for family socioeconomic position (SEP) and the cohort member's mother's age at her birth. The association between childhood SEP and AFP is partially mediated by early-life conditions, and the association between early-life conditions and AFP is partially mediated by emotional and behavioural problems in childhood. The overall relationship between early-life adversities and AFP appears to be approximately additive.

  18. Handgrip strength is associated with metabolic syndrome among middle-aged and elderly community-dwelling persons.

    PubMed

    Kawamoto, Ryuichi; Ninomiya, Daisuke; Kasai, Yoshihisa; Kusunoki, Tomo; Ohtsuka, Nobuyuki; Kumagi, Teru; Abe, Masanori

    2016-01-01

    The association of low muscle strength with cardio-metabolic risks remains controversial. The present study included 742 men aged 70 ± 9 years and 937 women aged 70 ± 8 years from a rural village. We examined the cross-sectional relationship between relative muscle strength defined by handgrip strength (HGS)/body weight (BW) ratio, and metabolic syndrome (MetS) based on the modified criteria of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP) III report and its components. Of these, 203 men (27.4%) and 448 women (47.8%) had MetS. In men, increasing quartile of HGS/BW ratio was significantly and independently associated with high waist circumference {odds ratio, 0.31; 95% confidence interval (CI), 0.24-0.41} and elevated triglyceridemia (0.71, 0.59-0.86). In women, it was also significantly and independently associated with high waist circumference (0.41; 0.36-0.48), high blood pressure (0.78; 0.66-0.92), Low HDL-cholesterolemia (0.84; 0.73-0.98) and elevated triglyceridemia (0.65; 0.53-0.79). In both genders, the prevalence of MetS significantly decreased in relation to increasing HGS/BW ratio. After adjustment for age, smoking status, drinking status, LDL-C, estimated glomerular filtration ratio (eGFR), and medication, the respective odds ratio (95% CI) for the quartile of HGS/BW ratio for MetS was 1.00, 0.54 (0.34-0.85), 0.32 (0.19-0.53), and 0.16 (0.09-0.29) in men, and 1.00, 0.76 (0.50-1.16), 0.33 (0.22-0.51), and 0.16 (0.10-0.25) in women. These results suggest that HGS/BW ratio was significantly and negatively associated with an increased risk of cardio-metabolic disorders in Japanese-community dwelling persons.

  19. Group precipitation and age hardening of nanostructured Fe-based alloys with ultra-high strengths

    DOE PAGES

    Jiao, Z. B.; Luan, J. H.; Miller, M. K.; Yu, C. Y.; Liu, C. T.

    2016-02-19

    The precipitation of nanoparticles plays a key role in determining the properties of many structural materials, and the understanding of their formation and stabilization mechanisms has been a long standing interest in the material field. However, the critical issues involving the group precipitation of various nanoparticles and their cooperative hardening mechanism remain elusive in the newly discovered Fe-based alloys with nanostructures. Here we quantitatively elucidate the nucleation mechanism, evolution kinetics and hardening effects of the group-precipitated nanoparticles in the Fe-Cu-Ni-Al-based alloys by atom probe tomography together with both first-principles and thermodynamic calculations. Our results provide the compelling evidence for twomore » interesting but complex group precipitation pathways of nanoparticles, i.e., the Cu-rich and NiAl-based precipitations. Lastly, the co-existence of the two precipitation pathways plays a key role in age hardening kinetics and ultimately enhances the hardening response, as compared to the single particle type of strengthening, therefore providing an effective new approach for strengthening materials for structural applications.« less

  20. Group precipitation and age hardening of nanostructured Fe-based alloys with ultra-high strengths.

    PubMed

    Jiao, Z B; Luan, J H; Miller, M K; Yu, C Y; Liu, C T

    2016-02-19

    The precipitation of nanoparticles plays a key role in determining the properties of many structural materials, and the understanding of their formation and stabilization mechanisms has been a long standing interest in the material field. However, the critical issues involving the group precipitation of various nanoparticles and their cooperative hardening mechanism remain elusive in the newly discovered Fe-based alloys with nanostructures. Here we quantitatively elucidate the nucleation mechanism, evolution kinetics and hardening effects of the group-precipitated nanoparticles in the Fe-Cu-Ni-Al-based alloys by atom probe tomography together with both first-principles and thermodynamic calculations. Our results provide the compelling evidence for two interesting but complex group precipitation pathways of nanoparticles, i.e., the Cu-rich and NiAl-based precipitations. The co-existence of the two precipitation pathways plays a key role in age hardening kinetics and ultimately enhances the hardening response, as compared to the single particle type of strengthening, therefore providing an effective new approach for strengthening materials for structural applications.

  1. Group precipitation and age hardening of nanostructured Fe-based alloys with ultra-high strengths

    NASA Astrophysics Data System (ADS)

    Jiao, Z. B.; Luan, J. H.; Miller, M. K.; Yu, C. Y.; Liu, C. T.

    2016-02-01

    The precipitation of nanoparticles plays a key role in determining the properties of many structural materials, and the understanding of their formation and stabilization mechanisms has been a long standing interest in the material field. However, the critical issues involving the group precipitation of various nanoparticles and their cooperative hardening mechanism remain elusive in the newly discovered Fe-based alloys with nanostructures. Here we quantitatively elucidate the nucleation mechanism, evolution kinetics and hardening effects of the group-precipitated nanoparticles in the Fe-Cu-Ni-Al-based alloys by atom probe tomography together with both first-principles and thermodynamic calculations. Our results provide the compelling evidence for two interesting but complex group precipitation pathways of nanoparticles, i.e., the Cu-rich and NiAl-based precipitations. The co-existence of the two precipitation pathways plays a key role in age hardening kinetics and ultimately enhances the hardening response, as compared to the single particle type of strengthening, therefore providing an effective new approach for strengthening materials for structural applications.

  2. Group precipitation and age hardening of nanostructured Fe-based alloys with ultra-high strengths

    PubMed Central

    Jiao, Z. B.; Luan, J. H.; Miller, M. K.; Yu, C. Y.; Liu, C. T.

    2016-01-01

    The precipitation of nanoparticles plays a key role in determining the properties of many structural materials, and the understanding of their formation and stabilization mechanisms has been a long standing interest in the material field. However, the critical issues involving the group precipitation of various nanoparticles and their cooperative hardening mechanism remain elusive in the newly discovered Fe-based alloys with nanostructures. Here we quantitatively elucidate the nucleation mechanism, evolution kinetics and hardening effects of the group-precipitated nanoparticles in the Fe-Cu-Ni-Al-based alloys by atom probe tomography together with both first-principles and thermodynamic calculations. Our results provide the compelling evidence for two interesting but complex group precipitation pathways of nanoparticles, i.e., the Cu-rich and NiAl-based precipitations. The co-existence of the two precipitation pathways plays a key role in age hardening kinetics and ultimately enhances the hardening response, as compared to the single particle type of strengthening, therefore providing an effective new approach for strengthening materials for structural applications. PMID:26892834

  3. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age. PMID:25929653

  4. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age.

  5. Maternal support in early childhood predicts larger hippocampal volumes at school age.

    PubMed

    Luby, Joan L; Barch, Deanna M; Belden, Andy; Gaffrey, Michael S; Tillman, Rebecca; Babb, Casey; Nishino, Tomoyuki; Suzuki, Hideo; Botteron, Kelly N

    2012-02-21

    Early maternal support has been shown to promote specific gene expression, neurogenesis, adaptive stress responses, and larger hippocampal volumes in developing animals. In humans, a relationship between psychosocial factors in early childhood and later amygdala volumes based on prospective data has been demonstrated, providing a key link between early experience and brain development. Although much retrospective data suggests a link between early psychosocial factors and hippocampal volumes in humans, to date there has been no prospective data to inform this potentially important public health issue. In a longitudinal study of depressed and healthy preschool children who underwent neuroimaging at school age, we investigated whether early maternal support predicted later hippocampal volumes. Maternal support observed in early childhood was strongly predictive of hippocampal volume measured at school age. The positive effect of maternal support on hippocampal volumes was greater in nondepressed children. These findings provide prospective evidence in humans of the positive effect of early supportive parenting on healthy hippocampal development, a brain region key to memory and stress modulation. PMID:22308421

  6. Modeling early-onset post-ischemic seizures in aging mice

    PubMed Central

    Wu, Chiping; Wang, Justin; Peng, Jessie; Patel, Nisarg; Huang, Yayi; Gao, Xiaoxing; Aljarallah, Salman; Eubanks, James H; McDonald, Robert; Zhang, Liang

    2016-01-01

    Stroke is the leading cause of seizures and epilepsy in the aged population, with post-stroke seizures being a poor prognostic factor. The pathological processes underlying post-stroke seizures are not well understood and studies of these seizures in aging/aged animals remain scarce. Therefore, our primary objective was to model post-stroke seizures in aging mice (C57 black strain, 16–20 month-old), with a focus on early-onset, convulsive seizures that occur within 24-hours of brain ischemia. We utilized a middle cerebral artery occlusion model and examined seizure activity and brain injury using combined behavioral and electroencephalographic monitoring and histological assessments. Aging mice exhibited vigorous convulsive seizures within hours of the middle cerebral artery occlusion. These seizures manifested with jumping, rapid running, barrel-rolling and/or falling all in the absence of hippocampal-cortical electrographic discharges. Seizure development was closely associated with severe brain injury and acute mortality. Anticonvulsive treatments after seizure occurrence offered temporary seizure control but failed to improve animal survival. A separate cohort of adult mice (6–8 months-old) exhibited analogous early-onset convulsive seizures following the middle cerebral artery occlusion but had better survival outcomes following anticonvulsive treatment. Collectively, our data suggest that early-onset convulsive seizures are a result of severe brain ischemia in aging animals. PMID:25943585

  7. Modeling early-onset post-ischemic seizures in aging mice.

    PubMed

    Wu, Chiping; Wang, Justin; Peng, Jessie; Patel, Nisarg; Huang, Yayi; Gao, Xiaoxing; Aljarallah, Salman; Eubanks, James H; McDonald, Robert; Zhang, Liang

    2015-09-01

    Stroke is the leading cause of seizures and epilepsy in the aged population, with post-stroke seizures being a poor prognostic factor. The pathological processes underlying post-stroke seizures are not well understood and studies of these seizures in aging/aged animals remain scarce. Therefore, our primary objective was to model post-stroke seizures in aging mice (C57 black strain, 16-20 months-old), with a focus on early-onset, convulsive seizures that occur within 24-hours of brain ischemia. We utilized a middle cerebral artery occlusion model and examined seizure activity and brain injury using combined behavioral and electroencephalographic monitoring and histological assessments. Aging mice exhibited vigorous convulsive seizures within hours of the middle cerebral artery occlusion. These seizures manifested with jumping, rapid running, barrel-rolling and/or falling all in the absence of hippocampal-cortical electrographic discharges. Seizure development was closely associated with severe brain injury and acute mortality. Anticonvulsive treatments after seizure occurrence offered temporary seizure control but failed to improve animal survival. A separate cohort of adult mice (6-8 months-old) exhibited analogous early-onset convulsive seizures following the middle cerebral artery occlusion but had better survival outcomes following anticonvulsive treatment. Collectively, our data suggest that early-onset convulsive seizures are a result of severe brain ischemia in aging animals.

  8. Relative Handgrip Strength Is a Simple Indicator of Cardiometabolic Risk among Middle-Aged and Older People: A Nationwide Population-Based Study in Taiwan

    PubMed Central

    Lee, Wei-Ju; Peng, Li-Ning; Chiou, Shu-Ti; Chen, Liang-Kung

    2016-01-01

    Background Muscle strength may play an important role in cardiovascular health. The study was intended to evaluate the association between cardiometabolic risk, risk of coronary artery disease and handgrip strength by using the relative handgrip strength. Materials and Methods Data of 927 Taiwanese aged 53 years and older (510 men and 417 women) were retrieved from a nationwide representative population-based cohort cross-sectional study in 2006. All participants were interviewed face-to-face and received measures of anthropometry, dominant handgrip strength, relative handgrip strength (summation of both handgrip strength divided by body mass index) and serum biomarkers. Results Multivariate linear regression analysis showed the significant association between relative handgrip strength and favorable cardiometabolic risk factors including blood pressure, triglyceride, total cholesterol to high density cholesterol(HDL-C) ratio, glycohemoglobin (HbA1c), uric acid, Framingham risk score in men, and HDL-C, fasting glucose, HbA1c, log hsCRP in women. Dominant hand grip strength was only associated with log hsCRP in women. (p<0.05 for all), but was not significant associated with all cardiovascular biomarkers and FRS in both sex. Conclusions Joint with handgrip strength and body size, as relative handgrip strength, may be a better tool to capture conceptual concomitant health, which may be a simple, inexpensive, and easy-to-use tool when targeting cardiovascular health in public health level. PMID:27559733

  9. Radiographic morphometry and densitometry predict strength of cadaveric proximal humeri more reliably than age and DXA scan density.

    PubMed

    Skedros, John G; Knight, Alex N; Pitts, Todd C; O'Rourke, Peter J; Burkhead, Wayne Z

    2016-02-01

    Methods are needed for identifying poorer quality cadaver proximal humeri to ensure that they are not disproportionately segregated into experimental groups for fracture studies. We hypothesized that measurements made from radiographs of cadaveric proximal humeri are stronger predictors of fracture strength than chronological age or bone density values derived from dual-energy x-ray absorptiometry (DXA) scans. Thirty-three proximal humeri (range: 39-78 years) were analyzed for: (1) bone mineral density (BMD, g/cm(2)) using DXA, (2) bulk density (g/cm(3)) using DXA and volume displacement, (3) regional bone density in millimeters of aluminum (mmAl) using radiographs, and (4) regional mean (medial+lateral) cortical thickness and cortical index (CI) using radiographs. The bones were then fractured simulating a fall. Strongest correlations with ultimate fracture load (UFL) were: mean cortical thickness at two diaphyseal locations (r = 0.71; p < 0.001), and mean mmAl in the humeral head (r = 0.70; p < 0.001). Weaker correlations were found between UFL and DXA-BMD (r = 0.60), bulk density (r = 0.43), CI (r = 0.61), and age (r = -0.65) (p values <0.01). Analyses between UFL and the product of any two characteristics showed six combinations with r-values >0.80, but none included DXA-derived density, CI, or age. Radiographic morphometric and densitometric measurements from radiographs are therefore stronger predictors of UFL than age, CI, or DXA-derived density measurements. PMID:26218571

  10. Orbitofrontal Cortex and the Early Processing of Visual Novelty in Healthy Aging.

    PubMed

    Kaufman, David A S; Keith, Cierra M; Perlstein, William M

    2016-01-01

    Event-related potential (ERP) studies have previously found that scalp topographies of attention-related ERP components show frontal shifts with age, suggesting an increased need for compensatory frontal activity to assist with top-down facilitation of attention. However, the precise neural time course of top-down attentional control in aging is not clear. In this study, 20 young (mean: 22 years) and 14 older (mean: 64 years) adults completed a three-stimulus visual oddball task while high-density ERPs were acquired. Colorful, novel distracters were presented to engage early visual processing. Relative to young controls, older participants exhibited elevations in occipital early posterior positivity (EPP), approximately 100 ms after viewing colorful distracters. Neural source models for older adults implicated unique patterns of orbitofrontal cortex (OFC; BA 11) activity during early visual novelty processing (100 ms), which was positively correlated with subsequent activations in primary visual cortex (BA 17). Older adult EPP amplitudes and OFC activity were associated with performance on tests of complex attention and executive function. These findings are suggestive of age-related, compensatory neural changes that may driven by a combination of weaker cortical efficiency and increased need for top-down control over attention. Accordingly, enhanced early OFC activity during visual attention may serve as an important indicator of frontal lobe integrity in healthy aging. PMID:27199744

  11. COMPARISON OF GESTATIONAL AGE AT DELIVERY BASED ON LAST MENSTRUAL PERIOD AND EARLY ULTRASOUND

    EPA Science Inventory

    Reported date of last menstrual period (LMP) is commonly used to estimate gestational age but may be unreliable if recall is inaccurate or time between menstruation and ovulation differs from the presumed 15-day interval. Early ultrasound is generally a more accurate method than ...

  12. Assessing Age of Onset Effects in (Early) Child L2 Acquisition

    ERIC Educational Resources Information Center

    Unsworth, Sharon

    2013-01-01

    This study compares the development of three different types of bilingual/second language children in their acquisition of gender-marking on adjectives in Dutch to investigate whether there is evidence for age-of-onset effects in early childhood as proposed by Meisel (2009). The three groups of children are: simultaneous bilingual children,…

  13. Parenthood, Stress, and Mental Health in Late Midlife and Early Old Age

    ERIC Educational Resources Information Center

    Pudrovska, Tetyana

    2009-01-01

    Using 2 waves of the Wisconsin Longitudinal Study, I examine psychological consequences of potentially stressful, non-normative, or "off-time" aspects of the parental role in late midlife and early old age, including coresidence with adult children, stepparenthood, and parental bereavement. Additionally, I analyze gender differences in…

  14. Age at adoption from institutional care as a window into the lasting effects of early experiences.

    PubMed

    Julian, Megan M

    2013-06-01

    One of the major questions of human development is how early experience impacts the course of development years later. Children adopted from institutional care experience varying levels of deprivation in their early life followed by qualitatively better care in an adoptive home, providing a unique opportunity to study the lasting effects of early deprivation and its timing. The effects of age at adoption from institutional care are discussed for multiple domains of social and behavioral development within the context of several prominent developmental hypotheses about the effects of early deprivation (cumulative effects, experience-expectant developmental programming, and experience-adaptive developmental programming). Age at adoption effects are detected in a majority of studies, particularly when children experienced global deprivation and were assessed in adolescence. For most outcomes, institutionalization beyond a certain age is associated with a step-like increase in risk for lasting social and behavioral problems, with the step occurring at an earlier age for children who experienced more severe levels of deprivation. Findings are discussed in terms of their concordance and discordance with our current hypotheses, and speculative explanations for the findings are offered.

  15. Early Characteristics of Children with ASD Who Demonstrate Optimal Progress between Age Two and Four

    ERIC Educational Resources Information Center

    Moulton, Emily; Barton, Marianne; Robins, Diana L.; Abrams, Danielle N.; Fein, Deborah

    2016-01-01

    Although for many children, Autism Spectrum Disorder (ASD) is a lifelong disability, a subset of children with ASD lose their diagnosis and show typical cognitive and adaptive abilities. The ages at which this transition can occur is not known, but it sometimes occurs quite early. Participants in the current study were 207 children with an ASD at…

  16. Treatment Moderators and Predictors of Outcome in the Treatment of Early Age Mania (TEAM) Study

    ERIC Educational Resources Information Center

    Vitiello, Benedetto; Riddle, Mark A.; Yenokyan, Gayane; Axelson, David A.; Wagner, Karen D.; Joshi, Paramjit; Walkup, John T.; Luby, Joan; Birmaher, Boris; Ryan, Neal D.; Emslie, Graham; Robb, Adelaide; Tillman, Rebecca

    2012-01-01

    Objective: Both the diagnosis and treatment of bipolar disorder in youth remain the subject of debate. In the Treatment of Early Age Mania (TEAM) study, risperidone was more effective than lithium or divalproex in children diagnosed with bipolar mania and highly comorbid with attention-deficit/hyperactivity disorder (ADHD). We searched for…

  17. Age at adoption from institutional care as a window into the lasting effects of early experiences

    PubMed Central

    Julian, Megan M.

    2013-01-01

    One of the major questions of human development is how early experience impacts the course of development years later. Children adopted from institutional care experience varying levels of deprivation in their early life followed by qualitatively better care in an adoptive home, providing a unique opportunity to study the lasting effects of early deprivation and its timing. The effects of age at adoption from institutional care are discussed for multiple domains of social and behavioral development within the context of several prominent developmental hypotheses about the effects of early deprivation (cumulative effects, experience-expectant developmental programming, and experience-adaptive developmental programming). Age at adoption effects are detected in a majority of studies, particularly when children experienced global deprivation and were assessed in adolescence. For most outcomes, institutionalization beyond a certain age is associated with a step-like increase in risk for lasting social and behavioral problems, with the step occurring at an earlier age for children who experienced more severe levels of deprivation. Findings are discussed in terms of their concordance and discordance with our current hypotheses, and speculative explanations for the findings are offered. PMID:23576122

  18. Orbitofrontal Cortex and the Early Processing of Visual Novelty in Healthy Aging

    PubMed Central

    Kaufman, David A. S.; Keith, Cierra M.; Perlstein, William M.

    2016-01-01

    Event-related potential (ERP) studies have previously found that scalp topographies of attention-related ERP components show frontal shifts with age, suggesting an increased need for compensatory frontal activity to assist with top-down facilitation of attention. However, the precise neural time course of top-down attentional control in aging is not clear. In this study, 20 young (mean: 22 years) and 14 older (mean: 64 years) adults completed a three-stimulus visual oddball task while high-density ERPs were acquired. Colorful, novel distracters were presented to engage early visual processing. Relative to young controls, older participants exhibited elevations in occipital early posterior positivity (EPP), approximately 100 ms after viewing colorful distracters. Neural source models for older adults implicated unique patterns of orbitofrontal cortex (OFC; BA 11) activity during early visual novelty processing (100 ms), which was positively correlated with subsequent activations in primary visual cortex (BA 17). Older adult EPP amplitudes and OFC activity were associated with performance on tests of complex attention and executive function. These findings are suggestive of age-related, compensatory neural changes that may driven by a combination of weaker cortical efficiency and increased need for top-down control over attention. Accordingly, enhanced early OFC activity during visual attention may serve as an important indicator of frontal lobe integrity in healthy aging. PMID:27199744

  19. Spiroplasma infection causes either early or late male killing in Drosophila, depending on maternal host age

    NASA Astrophysics Data System (ADS)

    Kageyama, Daisuke; Anbutsu, Hisashi; Shimada, Masakazu; Fukatsu, Takema

    2007-04-01

    Symbiont-induced male-killing phenotypes have been found in a variety of insects. Conventionally, these phenotypes have been divided into two categories according to the timing of action: early male killing at embryonic stages and late male killing at late larval stages. In Drosophila species, endosymbiotic bacteria of the genus Spiroplasma have been known to cause early male killing. Here, we report that a spiroplasma strain normally causing early male killing also induces late male killing depending on the maternal host age: male-specific mortality of larvae and pupae was more frequently observed in the offspring of young females. As the lowest spiroplasma density and occasional male production were also associated with newly emerged females, we proposed the density-dependent hypothesis for the expression of early and late male-killing phenotypes. Our finding suggested that (1) early and late male-killing phenotypes can be caused by the same symbiont and probably by the same mechanism; (2) late male killing may occur as an attenuated expression of early male killing; (3) expression of early and late male-killing phenotypes may be dependent on the symbiont density, and thus, could potentially be affected by the host immunity and regulation; and (4) early male killing and late male killing could be alternative strategies adopted by microbial reproductive manipulators.

  20. Higher Daily Physical Activities Continue to Preserve Muscle Strength After Mid-Life, But Not Muscle Mass After Age of 75

    PubMed Central

    Hwang, An-chun; Zhan, Yu-Rui; Lee, Wei-Ju; Peng, Li-Ning; Chen, Liang-Yu; Lin, Ming-Hsien; Liu, Li-Kuo; Chen, Liang-Kung

    2016-01-01

    Abstract The objective of this study is to explore the impact of aging and daily physical activities (PA) on muscle mass and muscle strength among community-dwelling people in Taiwan. The design is a cross-sectional study. Setting is a population-based community study. One thousand eight hundred thirty-nine community-dwelling people aged 50 years and older in Taiwan participated in the study. Measurements include demographic characteristics, Charlson Comorbidity Index (CCI) for multimorbidity, mini-nutritional assessment (MNA) for nutritional evaluation, functional autonomy measurement system (SMAF) for functional capacity, Chinese version mini mental state examination (MMSE), 5-item Taiwan Geriatric Depression Scale (TGDS-5), Chinese version of International Physical Activity Questionnaire (IPAQ), height-adjusted skeletal muscle index (SMI) by dual-energy X-ray absorptiometry, handgrip strength, timed 6-m walking test for usual gait speed. Laboratory measurements include testosterone, sex-hormone binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1 (IGF-1), high-sensitivity C-reactive protein (hsCRP), 25-OH vitamin D, and insulin resistance. After adjusted for age, the lowest PA tertile was associated with multimorbidity, poorer functional capacity and nutritional status, more depressive symptoms, lower SMI and lower handgrip strength, and lower free androgen index (FAI) in men. The negative association between PA and low SMI was more significant among subjects aged younger than 65 and the association decreased with older age. For subjects aged younger than 65, moderate daily PA (Q2) group had lower risk of low SMI compared with Q1 participants (OR: 0.62, 95% CI = 0.39–0.98, P = 0.040). For muscle strength, higher daily PA was associated with lower risk of low handgrip strength after age of 65 and the effect was dose-dependent. The effect was attenuated by potential confounders during age 65 to 74, while after

  1. Higher Daily Physical Activities Continue to Preserve Muscle Strength After Mid-Life, But Not Muscle Mass After Age of 75.

    PubMed

    Hwang, An-Chun; Zhan, Yu-Rui; Lee, Wei-Ju; Peng, Li-Ning; Chen, Liang-Yu; Lin, Ming-Hsien; Liu, Li-Kuo; Chen, Liang-Kung

    2016-05-01

    The objective of this study is to explore the impact of aging and daily physical activities (PA) on muscle mass and muscle strength among community-dwelling people in Taiwan.The design is a cross-sectional study. Setting is a population-based community study.One thousand eight hundred thirty-nine community-dwelling people aged 50 years and older in Taiwan participated in the study.Measurements include demographic characteristics, Charlson Comorbidity Index (CCI) for multimorbidity, mini-nutritional assessment (MNA) for nutritional evaluation, functional autonomy measurement system (SMAF) for functional capacity, Chinese version mini mental state examination (MMSE), 5-item Taiwan Geriatric Depression Scale (TGDS-5), Chinese version of International Physical Activity Questionnaire (IPAQ), height-adjusted skeletal muscle index (SMI) by dual-energy X-ray absorptiometry, handgrip strength, timed 6-m walking test for usual gait speed. Laboratory measurements include testosterone, sex-hormone binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEA-S), insulin-like growth factor-1 (IGF-1), high-sensitivity C-reactive protein (hsCRP), 25-OH vitamin D, and insulin resistance.After adjusted for age, the lowest PA tertile was associated with multimorbidity, poorer functional capacity and nutritional status, more depressive symptoms, lower SMI and lower handgrip strength, and lower free androgen index (FAI) in men. The negative association between PA and low SMI was more significant among subjects aged younger than 65 and the association decreased with older age. For subjects aged younger than 65, moderate daily PA (Q2) group had lower risk of low SMI compared with Q1 participants (OR: 0.62, 95% CI = 0.39-0.98, P = 0.040). For muscle strength, higher daily PA was associated with lower risk of low handgrip strength after age of 65 and the effect was dose-dependent. The effect was attenuated by potential confounders during age 65 to 74, while after age 75, the

  2. Mobility in Central European Late Eneolithic and Early Bronze Age: femoral cross-sectional geometry.

    PubMed

    Sládek, Vladimír; Berner, Margit; Sailer, Robert

    2006-07-01

    Some scholars explain the absence of settlements in the Bohemian and Moravian Late Eneolithic (Corded Ware archaeological culture) as a consequence of pastoral subsistence with a high degree of mobility. However, recent archaeological studies argued that the archaeological record of the Late Eneolithic in Central Europe exhibits evidence for sedentary subsistence with mixed agriculture, similar to the subsequent Early Bronze Age. Because the archaeological data do not allow us to address unambiguously the mobility pattern in these periods, we used cross-sectional analysis of the femoral midshaft to test mobility directly on the human skeletal record. The results of femoral midshaft geometry do not support a high degree of mobility in the Late Eneolithic in Central Europe. This conclusion is supported mainly by no significant differences in male groups between the Late Eneolithic and Early Bronze Age in mechanical robusticity and shape of the femoral midshaft, although Corded Ware males still exhibit the highest absolute mean values of the diaphyseal shape (I(A-P)/I(M-L)) ratio and antero-posterior second moment of area. However, Late Eneolithic females have significantly higher torsional and overall bending rigidity because of a significantly higher medio-lateral second moment of area. This finding cannot be directly linked with a higher degree of long-distance mobility for these females. A significant difference was also found in overall decrease of size parameters of the femoral midshaft cross section for one of the Early Bronze Age samples, the Wieselburger females. Since the decrease of size and mechanical robusticity for Wieselburger females does not correspond with the parameters of Early Bronze Age females, we can expect a mosaic pattern of changes during the Late Eneolithic and Early Bronze Age period, instead of a simple unidirectional (diachronic) change of the mechanical environment. PMID:16402366

  3. Revised timing of the South American early Paleogene land mammal ages

    NASA Astrophysics Data System (ADS)

    Woodburne, Michael O.; Goin, Francisco J.; Raigemborn, Maria Sol; Heizler, Matt; Gelfo, Javier N.; Oliveira, Edison V.

    2014-10-01

    A new Ar/Ar date on the Las Flores Tuff (Río Chico Group, Las Flores Fm., central Patagonia, Argentina) yielded an age of 49.512 ± 0.019 Ma. This tuff, which stratigraphically overlies the mammal-bearing deposits that produced the Las Flores fauna, helps constrain the age of the Itaboraian SALMA [South American Land Mammal Age] to which that fauna is referred. The new data also have implications for the age of succeeding mammal biochrons, such as the Riochican and “Sapoan” which are revised to being somewhat younger than previously interpreted. Although closer in age than formerly interpreted, they still are biotically distinct. Concomitant evaluations suggest that the Itaboraian SALMA is perhaps more contemporary with the EECO (Early Eocene Climatic Optimum) than previously considered. The Riochican may be interpreted as post-EECO, with its cooler climate consistent in that regard. A recent reconsideration of the chronology of elements of the Salamanca Formation resulted in the downward revision of the ages of the Peligran SALMA and the Carodnia Zone biochrons. These operations, together with our results, reflect a 9 m.y. gap in the late Paleocene and early Eocene land mammal record in South America.

  4. Voice quality of children with cochlear implants acquired at early and later ages

    NASA Astrophysics Data System (ADS)

    Campbell, Melanie M.; Hanstein, Stefanie; Ney, Christina

    2005-09-01

    The speech gains of children with cochlear implants (CIs) are well documented, but the literature on voice quality is sparse. It has reported atypical measures/ratings of voice pitch, pleasantness, timing, and acoustic features [Higgins et al. (2003); Perrin et al. (1998)]. Is voice quality now improving in children implanted very early? This pilot study compared the voice quality of (a) children with early acquired CIs and children with normal hearing and (b) the voice quality of children implanted later and earlier in life. Children aged 6 to 10 years, with early acquired CIs, and participants with normal hearing, age-matched to them, audio recorded sentences, vowels, and conversation. PERCI pressure measures were also performed. PERCI Differential and Oral Pressure values and Computerized Speech Lab (CSL) and Visipitch measures of voice-onset time and fundamental frequency were analyzed comparing the values from the hearing and the early implanted children and values gleaned from the study of Higgins et al. of children with later-acquired implants. CSL and Visipitch measures of intonation contour, intensity, and jitter were analyzed to compare the hearing and the early implanted participants. Ratings on the Wilson Voice Scale were correlated with measures of jitter, fundamental frequency, and intonation contour.

  5. Learning impairments identified early in life are predictive of future impairments associated with aging

    PubMed Central

    Hullinger, Rikki; Burger, Corinna

    2016-01-01

    The Morris water maze (MWM) behavioral paradigm is commonly used to measure spatial learning and memory in rodents. It is widely accepted that performance in the MWM declines with age. However, young rats ubiquitously perform very well on established versions of the water maze, suggesting that more challenging tasks may be required to reveal subtle differences in young animals. Therefore, we have used a one-day water maze and novel object recognition to test whether more sensitive paradigms of memory in young animals could identify subtle cognitive impairments early in life that might become accentuated later with senescence. We have found that these two tasks reliably separate young rats into inferior and superior learners, are highly correlated, and that performance on these tasks early in life is predictive of performance at 12 months of age. Furthermore, we have found that repeated training in this task selectively improves the performance of inferior learners, suggesting that behavioral training from an early age may provide a buffer against age-related cognitive decline. PMID:26283528

  6. Supporting Early Adolescent Learning and Social Strengths: Promoting Productive Contexts for Students At-Risk for EBD during the Transition to Middle School

    ERIC Educational Resources Information Center

    Farmer, Thomas W.; Hamm, Jill V.; Petrin, Robert A.; Robertson, Dylan; Murray, Robert A.; Meece, Judith L.; Brooks, Debbie Sprott

    2010-01-01

    This study involved a pilot examination of the impact of the Supporting Early Adolescent Learning and Social Strengths (SEALS) model on the 6th grade academic and social context following the transition to middle school. Two middle schools from a high poverty Appalachian school district were randomly assigned to the intervention and control…

  7. ME 04-3 EPIDEMIOLOGY AND CONSEQUENCES OF EARLY VASCULAR AGING.

    PubMed

    Hashimoto, Junichiro

    2016-09-01

    Arterial structure and function change progressively with advancing age. Owing to long-lasting repetitive stretch with intermittent cardiac contraction, elastic fibers in the tunica media of large arteries gradually degenerate and are replaced by collagenous fibers. Such medial degeneration causes elastic arteries to stiffen and dilate. However, the speed of the vascular aging varies considerably among individuals; a discrepancy often exists between the chronological age of an individual and the biological age of his or her arteries. In susceptible individuals the vascular aging process can be accelerated under the presence of various risk factors including hypertension, smoking, metabolic disorders, high sodium intake and hereditary traits. Early vascular aging is generally detected by vascular function tests such as pulse wave velocity (PWV) and pulse wave analysis. Stiffening of large elastic arteries increases the PWV, increases the amplitude of the incident pressure wave, and hastens the return of the reflected pressure wave. Consequent widening of the aortic pulse pressure elevates left ventricular afterload during systole and reduces coronary flow during diastole, thus predisposing to heart failure and myocardial ischemia. The excessive pulsatile pressure is also transmitted into the vulnerable microvasculature in the kidney and brain to cause albuminuria and lacunar infarction. Furthermore, aortic stiffening increases blood flow reversal in early diastole in the proximal descending aorta. The increased aortic flow reversal reduces renal blood flow and glomerular filtration rate, and in addition, it raises the risk of retrograde cerebral embolism of aortic mobile plaques. Such deleterious impacts of the central hemodynamic abnormalities on the vital end-organs predispose the patients with early vascular aging to premature cardiovascular diseases. Indeed, epidemiological prospective studies have demonstrated that aortic PWV and central hemodynamic indices

  8. ME 04-3 EPIDEMIOLOGY AND CONSEQUENCES OF EARLY VASCULAR AGING.

    PubMed

    Hashimoto, Junichiro

    2016-09-01

    Arterial structure and function change progressively with advancing age. Owing to long-lasting repetitive stretch with intermittent cardiac contraction, elastic fibers in the tunica media of large arteries gradually degenerate and are replaced by collagenous fibers. Such medial degeneration causes elastic arteries to stiffen and dilate. However, the speed of the vascular aging varies considerably among individuals; a discrepancy often exists between the chronological age of an individual and the biological age of his or her arteries. In susceptible individuals the vascular aging process can be accelerated under the presence of various risk factors including hypertension, smoking, metabolic disorders, high sodium intake and hereditary traits. Early vascular aging is generally detected by vascular function tests such as pulse wave velocity (PWV) and pulse wave analysis. Stiffening of large elastic arteries increases the PWV, increases the amplitude of the incident pressure wave, and hastens the return of the reflected pressure wave. Consequent widening of the aortic pulse pressure elevates left ventricular afterload during systole and reduces coronary flow during diastole, thus predisposing to heart failure and myocardial ischemia. The excessive pulsatile pressure is also transmitted into the vulnerable microvasculature in the kidney and brain to cause albuminuria and lacunar infarction. Furthermore, aortic stiffening increases blood flow reversal in early diastole in the proximal descending aorta. The increased aortic flow reversal reduces renal blood flow and glomerular filtration rate, and in addition, it raises the risk of retrograde cerebral embolism of aortic mobile plaques. Such deleterious impacts of the central hemodynamic abnormalities on the vital end-organs predispose the patients with early vascular aging to premature cardiovascular diseases. Indeed, epidemiological prospective studies have demonstrated that aortic PWV and central hemodynamic indices

  9. Early age of onset in fatal familial insomnia. Two novel cases and review of the literature.

    PubMed

    Harder, A; Gregor, A; Wirth, T; Kreuz, F; Schulz-Schaeffer, W J; Windl, O; Plotkin, M; Amthauer, H; Neukirch, K; Kretzschmar, H A; Kuhlmann, T; Braas, R; Hahne, H H; Jendroska, K

    2004-06-01

    Fatal familial insomnia (FFI) is a prion disease exhibiting the PRNP D178N/129M genotype. Features of this autosomal dominant illness are progressive insomnia, dysautonomia, myoclonus, cognitive decline and motor signs associated with thalamic nerve cell loss and gliosis. In contrast to the new variant of Creutzfeldt-Jakob disease (vCJD) the onset of FFI is in middle to late adulthood. We report two male patients who belong to a large German FFI kindred. They were examined clinically, and postmortem neuropathological examination was carried out in collaboration with the German reference centre for prion disease. Additionally, the prion protein gene (PRNP) was analysed. To identify further patients with disease onset under 30 years of age a comprehensive literature review was carried out. Two male patients presented with typical symptoms of FFI at the age of 23 and 24 years. In their kindred, the age of onset has never before been under 44 years of age. Our literature review identified five additional early onset cases who died at age 21 to 25 years. In all 22 reviewed FFI families the median manifestation age was 49.5 years. Although phenotypic variability of FFI is common, age of onset under 30 years has been considered to be a hallmark of vCJD with a mean manifestation at 27 years of age. Our findings underline that in addition to vCJD, FFI must be considered in cases of young-onset prion disease. This has considerable impact on clinical management and genetic counselling.

  10. Gulliver meets Descartes: early modern concepts of age-related memory loss.

    PubMed

    Schäfer, Daniel

    2003-03-01

    Age-related memory loss was a marginal issue in medical discussions during early modern times and until well into the second half of the 17th century. There are many possible explanations: the lack of similar traditions in antiquity and in the Middle Ages, insufficient physiological and morphological knowledge of the brain, and the underlying conflict between idealistic and materialistic perspectives on the functions of the soul and the conditions of these in old age. After these boundaries had been pushed back by the influence of Cartesianism and Iatromechanism, the problem of age-related memory loss was increasingly regarded as a physical illness and began to receive more attention. This trend first occurred in medicine, before spreading to the literary world, where the novel "Gulliver's Travels" is one clear and famous example.

  11. Canadian Sedentary Behaviour Guidelines for the Early Years (aged 0-4 years).

    PubMed

    Tremblay, Mark S; Leblanc, Allana G; Carson, Valerie; Choquette, Louise; Connor Gorber, Sarah; Dillman, Carrie; Duggan, Mary; Gordon, Mary Jane; Hicks, Audrey; Janssen, Ian; Kho, Michelle E; Latimer-Cheung, Amy E; Leblanc, Claire; Murumets, Kelly; Okely, Anthony D; Reilly, John J; Stearns, Jodie A; Timmons, Brian W; Spence, John C

    2012-04-01

    The Canadian Society for Exercise Physiology (CSEP), with assistance from multiple partners, stakeholders, and researchers, developed the first Canadian Sedentary Behaviour Guidelines for the Early Years (aged 0-4 years). These national guidelines are in response to a call from health and health care professionals, child care providers, and fitness practitioners for guidance on sedentary behaviour in the early years. The guideline development process followed the Appraisal of Guidelines for Research Evaluation (AGREE) II framework. The recommendations are informed by evidence from a systematic review that examined the relationships between sedentary behaviour (predominantly screen time) and health indicators (healthy body weight, bone and skeletal health, motor skill development, psychosocial health, cognitive development, and cardio-metabolic disease risk factors) for three age groups (infants aged <1 year; toddlers aged 1-2 years; preschoolers aged 3-4 years). Evidence from the review was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The new guidelines include a preamble to provide context, followed by the specific recommendations. The final guidelines benefitted from extensive on-line consultations with input from >900 domestic and international stakeholders, end-users, and key informants. The final guidelines state: for healthy growth and development, caregivers should minimize the time infants (aged <1 year), toddlers (aged 1-2 years), and preschoolers (aged 3-4 years) spend being sedentary during waking hours. This includes prolonged sitting or being restrained (e.g., stroller, high chair) for more than 1 h at a time. For those under 2 years, screen time (e.g., TV, computer, electronic games) is not recommended. For children 2-4 years, screen time should be limited to under 1 h per day; less is better.

  12. Early age thermal conditioning immediately reduces body temperature of broiler chicks in a tropical environment.

    PubMed

    De Basilio, V; Requena, F; León, A; Vilariño, M; Picard, M

    2003-08-01

    Early age thermal conditioning (TC) durably improves resistance of broilers to heat stress and reduces body temperature (Tb). Three experiments on broiler chicks were conducted to evaluate the effects of TC at 5 d of age on Tb variation measured by thermometer between 4 and 7 d of age, under a tropical environment. Because manipulation of chickens to measure Tb with a thermometer may increase Tb, a preliminary experiment on 13 3-to-4-wk-old male broilers compared Tb measured by telemetry to Tb measured in the terminal colon during three successive periods at 22, 33, and 22 degrees C. During heat exposure, Tb rapidly increased by 0.9 degrees C and plateaued over 24 h. During the last period, seven of the broilers rapidly reduced Tb to a plateau lower than the initial Tb, although six broilers exhibited more variable Tb. Measurement by thermometer underestimated on average core Tb by 0.28 degrees C at 22 degrees C and by 0.57 degrees C at 33 degrees C, whereas Tb recorded by telemetry was not affected by manipulation of the chickens. TC reduced Tb 24 h later in the three experiments. Compared to unexposed control chicks (N), 12 h of TC at 40 degrees C did not significantly reduce Tb at 7 d of age, although 24 h did. TC at 38 and 40 degrees C over 24 h significantly reduced Tb variation from 4 to 7 d of age compared to N chicks, whereas 36 degrees C did not. Withdrawing feed from the chicks for 2 h prior to measurement did not significantly reduce Tb at 4 and 7 d of age, but Tb reduction due to TC was greater in fed chicks (0.28 degrees C) than in chicks without feed (0.05 degrees C). Early age thermal conditioning at 38 to 40 degrees C at 5 d of age for 24 h reduced body temperature of 7-d-old male broilers.

  13. Early Neurodevelopmental Findings Predict School Age Cognitive Abilities in Duchenne Muscular Dystrophy: A Longitudinal Study

    PubMed Central

    Chieffo, Daniela; Brogna, Claudia; Berardinelli, Angela; D’Angelo, Grazia; Mallardi, Maria; D’Amico, Adele; Alfieri, Paolo; Mercuri, Eugenio; Pane, Marika

    2015-01-01

    Objective Neurodevelopmental and cognitive difficulties are known to occur frequently in boys with Duchenne muscular dystrophy but so far none of the published studies have reported both early neurodevelopmental assessments and cognitive tests in the same cohort. The aim of the present longitudinal study was to establish the correlation between early neurodevelopmental assessments performed in preschool boys and the cognitive scales performed at school age or later. Methods We performed cognitive tests at school age (mean age 5.7 year ±1.7 SD) (69 months+19 SD) in a cohort of Duchenne boys, previously assessed using the Griffiths scales before the age of 4 years (mean age when the Griffiths scales were performed 30 months ±8.9 SD). Results The range of total Developmental quotients on the Griffiths ranged between 56 and 116 (mean 89 ± 15.6 SD). The total Intelligence Quotients on the Wechsler scales ranged between 35 and 119 (mean 87 ± 17.2 SD). There was a significant correlation between the findings on the two scales. P = <0.0001. When we subdivided the cohort according to site of mutations, there was a difference between boys with mutations upstream exon 44 and those with mutations in exon 44–45 affecting Dp140 on both Developmental and Intelligence Quotient (p 0.01 and p 0,003 respectively). Conclusions Our results confirm that Duchenne boys tend to slightly underperform on both neurodevelopmental and cognitive assessments. Early neurodevelopmental findings correlated with the cognitive results obtained at school age with a clear concordance between subscales exploring similar domains on the two scales. PMID:26275215

  14. Early psychological intervention in accidentally injured children ages 2–16: a randomized controlled trial

    PubMed Central

    Kramer, Didier N.; Landolt, Markus A.

    2014-01-01

    Background Road traffic accidents (RTA) and burns are frequent events in children. Although many children recover spontaneously, a considerable number develop long-term psychological sequelae. Evidence on early psychological interventions to prevent such long-term problems is still scarce for school-age children and completely lacking for pre-school children. Objectives To evaluate the efficacy of an early two-session cognitive-behavioral intervention in 108 children ages 2–16 after RTAs and burns. Methods Children assessed at risk for the development of posttraumatic stress disorder (PTSD) were randomly assigned to either a control group offered treatment as usual or an intervention group. Primary outcomes were PTSD, behavioral problems, and depression symptoms. Baseline and blinded 3- and 6-month follow-up assessments were conducted. Results In pre-school children, no intervention effects were found. School-age children in the intervention group exhibited significantly fewer internalizing problems at 3-month follow-up relative to controls and a borderline significant time-by-group effect for PTSD intrusion symptoms was found (p=0.06). Conclusions This is the first study examining the efficacy of an indicated, early psychological intervention among both school-age and pre-school-age children. Because the intervention was ineffective for young children, no evidence-based practice can currently be suggested. Given that parents of pre-school children perceived the intervention as helpful, brief counseling of parents in terms of psychoeducation and training in coping skills still should be provided by clinicians, despite the current lack of evidence. To prevent trauma-related disorders in school-age children, the intervention might be used in a step-wise manner, where only children at risk for long-term psychological maladjustment are provided with psychological support. PMID:24987498

  15. Microstructural evolution of 7012 alloy during the early stages of artificial ageing

    SciTech Connect

    Ferragut, R.; Somoza, A.; Tolley, A.

    1999-11-26

    A study of the microstructural evolution of a commercial 7012 (Al-Zn-Mg-Cu) age-hardenable alloy following artificial ageing by high resolution and conventional transmission electron microscopy and positron annihilation lifetime spectroscopy is presented. At the early stages of decomposition, the microstructure included precipitation of either pre-precipitate solute clusters or Guinier-Preston zones and semi-coherent {eta}{prime} precipitates, with typical sizes between 1 and 10 nm. Quantitative information on the size, number density and morphology of the particles present in the microstructure was obtained. The results were correlated with those obtained using positron annihilation lifetime spectroscopy.

  16. [Early signs of mental disorders in children aged 3-12 years].

    PubMed

    Lassal, Rabah; Laurent, Marion; Purper-Ouakil, Diane

    2011-04-01

    Neurodevelopmental disorders, affective/emotional disorders and exposure to adverse life circumstances are the main sources of psychological impairment in school age children. They should be distinguished from transient psychological symptoms occurring in normal development that do not significantly affect children's emotional and social functioning. An early recognition and assessment is the first step towards adequate treatment of conditions associated with psychological impairment. Any severe or persistant behavioral or emotional symptom occurring in children should be considered a possible early sign of a neurodevelopmental disorder warranting further investigation. Neurodevelopmental disorders are generally associated with delays early in development affecting several domains (language, social functioning, emotional and behavorial regulation) and are predominant in boys. These disorders are highly comorbid and require multidisciplinary assessments and treatment plans. Emotional and behavioral conditions arising from early deprivation or maltreatment also affect various developmental domains and may have lasting consequences. Finally, many of the disorders showing rising prevalences in adolescence or early adulthood also have some developmental precursors before puberty. Progress in identification, appropriate assessment and treatment of early manifesting symptoms and conditions interfering with adaptive functioning is a major mental health issue requiring multidisciplinary competencies. PMID:21548229

  17. The origin of early age expansions induced in cementitious materials containing shrinkage reducing admixtures

    SciTech Connect

    Sant, Gaurav; Lothenbach, Barbara; Juilland, Patrick; Le Saout, Gwenn; Weiss, Jason; Scrivener, Karen

    2011-03-15

    Studies on the early-age shrinkage behavior of cement pastes, mortars, and concretes containing shrinkage reducing admixtures (SRAs) have indicated these mixtures frequently exhibit an expansion shortly after setting. While the magnitude of the expansion has been noted to be a function of the chemistry of the cement and the admixture dosage; the cause of the expansion is not clearly understood. This investigation uses measurements of autogenous deformation, X-ray diffraction, pore solution analysis, thermogravimetry, and scanning electron microscopy to study the early-age properties and describe the mechanism of the expansion in OPC pastes made with and without SRA. The composition of the pore solution indicates that the presence of the SRA increases the portlandite oversaturation level in solution which can result in higher crystallization stresses which could lead to an expansion. This observation is supported by deformation calculations for the systems examined.

  18. Age of Diagnosis of Squamous Cell Cervical Carcinoma and Early Sexual Experience

    PubMed Central

    Edelstein, Zoe R.; Madeleine, Margaret M.; Hughes, James P.; Johnson, Lisa G.; Schwartz, Stephen M.; Galloway, Denise A.; Carter, Joseph J.; Koutsky, Laura A.

    2009-01-01

    Background Given the established links between young age at first intercourse (AFI), number of sex partners, high-risk human papillomavirus infection, and squamous cell cervical cancer (SCC), we hypothesized that women diagnosed with SCC at younger ages would be more likely to report young AFI than women diagnosed later in life. Methods We performed a population-based investigation among invasive SCC cases who were diagnosed between 1986 and 2004, were 22 to 53 years old, and lived in the metropolitan Seattle-Puget Sound region (n=333). Using multivariate linear regression, we estimated coefficients and 95% confidence intervals (CI) to assess the association between age at SCC diagnosis and AFI (<15, 15–18, ≥19) and number of sex partners before age 20 (0, 1, 2–4, 5–14, 15+), accounting for birth year and other factors. Interactions were assessed using the likelihood ratio test. Results The interval between AFI and SCC diagnosis ranged from 4 to 35 years. In a multivariate model, compared to SCC cases reporting AFI≥19, the mean age of diagnosis was 3.1 years younger for SCC cases reporting AFI<15 (CI: −5.8, −0.5) and 2.6 years younger for SCC cases reporting AFI 15–18 years (CI: −4.6, −0.6). Although number of sex partners before age 20 was associated with age at SCC diagnosis in a crude analysis, the association was not independent of AFI. However, in the AFI≥19 and AFI<15 groups, differences in effect were seen by number of sex partners before age 20 (p for interaction=0.08), with the association remaining strong and significant only in the AFI<15 group that had 2 or more partners before age 20 (coefficient: −4.2, CI: −6.3, −2.1). Conclusion Among younger and middle-aged women with SCC, early age of diagnosis was associated with early AFI, though the effect appeared to be modified by number of sex partners before age 20. PMID:19318437

  19. Up, Not Down: The Age Curve in Happiness from Early Adulthood to Midlife in Two Longitudinal Studies

    ERIC Educational Resources Information Center

    Galambos, Nancy L.; Fang, Shichen; Krahn, Harvey J.; Johnson, Matthew D.; Lachman, Margie E.

    2015-01-01

    Happiness is an important indicator of well-being, and little is known about how it changes in the early adult years. We examined trajectories of happiness from early adulthood to midlife in 2 Canadian longitudinal samples: high school seniors followed from ages 18-43 and university seniors followed from ages 23-37. Happiness increased into the…

  20. Familial Risk of Early Suicide: Variations by Age and Sex of Children and Parents

    ERIC Educational Resources Information Center

    Garssen, Joop; Deerenberg, Ingeborg; Mackenbach, Johan P.; Kerkhof, Ad; Kunst, Anton E.

    2011-01-01

    To determine familial risk of early suicide, data on cause of death of all Dutch residents aged 20-55 years who died between 1995 and 2001 were linked to data of their parents. Men whose father died by suicide had a higher odds of suicide themselves, relative to men whose father died of other causes (Odds Ratio (OR): 2.5; 95% confidence interval:…

  1. Exercise boosts hippocampal volume by preventing early age-related gray matter loss.

    PubMed

    Fuss, Johannes; Biedermann, Sarah V; Falfán-Melgoza, Claudia; Auer, Matthias K; Zheng, Lei; Steinle, Jörg; Hörner, Felix; Sartorius, Alexander; Ende, Gabriele; Weber-Fahr, Wolfgang; Gass, Peter

    2014-02-01

    Recently, a larger hippocampus was found in exercising mice and men. Here we studied the morphological underpinnings in wheel running mice by longitudinal magnetic resonance imaging. Voxel-based morphometry revealed that running increases hippocampal volume by inhibiting an early age-related gray matter loss. Disruption of neurogenesis-related neuroplasticity by focalized irradiation is sufficient to block positive effects of exercise on macroscopic brain morphology. PMID:24178895

  2. The effects of early grade retention: Effect modification by prior achievement and age.

    PubMed

    Vandecandelaere, Machteld; Vansteelandt, Stijn; De Fraine, Bieke; Van Damme, Jan

    2016-02-01

    This study examines the effects of early grade retention and different effects according to prior achievement and age. Within a population of children at risk of early retention, we compared the development throughout primary school in mathematics achievement after kindergarten retention, first-grade retention, and continuous promotion. Analyzing data from a large-scale longitudinal study using covariate balancing propensity score weighting, the findings revealed that early grade repeaters would score higher in mathematics if they were promoted each year instead. However, the effects diminished or even disappeared in the long term. Compared to kindergarten retention, first-grade retention was found to be more harmful for the mathematics development of younger children specifically. PMID:26790704

  3. The Enduring Predictive Significance of Early Maternal Sensitivity: Social and Academic Competence Through Age 32 Years

    PubMed Central

    Raby, K. Lee; Roisman, Glenn I.; Fraley, R. Chris; Simpson, Jeffry A.

    2014-01-01

    This study leveraged data from the Minnesota Longitudinal Study of Risk and Adaptation (N = 243) to investigate the predictive significance of maternal sensitivity during the first three years of life for social and academic competence through age 32 years. Structural model comparisons replicated previous findings that early maternal sensitivity predicts social skills and academic achievement through mid-adolescence in a manner consistent with an Enduring Effects model of development and extended these findings using heterotypic indicators of social (effectiveness of romantic engagement) and academic competence (educational attainment) during adulthood. Although early socioeconomic factors and child gender accounted for the predictive significance of maternal sensitivity for social competence, covariates did not fully account for associations between early sensitivity and academic outcomes PMID:25521785

  4. Do Economic Recessions During Early and Mid-Adulthood Influence Cognitive Function in Older Age?

    PubMed Central

    Leist, Anja K.; Hessel, Philipp; Avendano, Mauricio

    2014-01-01

    Background Fluctuations in the national economy shape labour market opportunities and outcomes, which in turn may influence the accumulation of cognitive reserve. This study examines whether economic recessions experienced in early and mid-adulthood are associated with later-life cognitive function. Method Data came from 12,020 respondents in 11 countries participating in the Survey of Health, Ageing and Retirement in Europe (SHARE). Cognitive assessments in 2004/5 and 2006/7 were linked to complete work histories retrospectively collected in 2008/9, and to historical annual data on fluctuations in Gross Domestic Product (GDP) per capita for each country. Controlling for confounders, we assessed whether recessions experienced at ages 25-34, 35-44 and 45-49 were associated with cognitive function at ages 50-74. Results Among men, each additional recession at ages 45-49 was associated with worse cognitive function at ages 50-74 (b = -0.06, Confidence Interval [CI] -0.11, -0.01). Among women, each additional recession at ages 25-44 was associated with worse cognitive function at ages 50-74 (b25-34 = -0.03, CI -0.04, -0.01; b35-44= -0.02, CI -0.04, -0.00). Among men, recessions at ages 45-49 influenced risk of being laid-off, whereas among women, recessions at ages 25-44 led to working part-time and higher likelihood of downward occupational mobility, which were all predictors of worse later-life cognitive function. Conclusions Recessions at ages 45-49 among men and 25-44 among women are associated with later-life cognitive function, possibly via more unfavourable labour market trajectories. If replicated in future studies, findings may indicate that policies that ameliorate the impact of recessions on labour market outcomes may promote later-life cognitive function. PMID:24258197

  5. The Early Stone Age lithic assemblages of Gadeb (Ethiopia) and the Developed Oldowan/early Acheulean in East Africa.

    PubMed

    de la Torre, Ignacio

    2011-06-01

    The Early Stone Age sites of Gadeb (Ethiopian South-East Plateau) were excavated under the direction of Desmond Clark in the 1970s. Dated to between 1.45 and 0.7 Ma, Gadeb proved that humans had already occupied high altitude areas in the Lower Pleistocene. Despite the importance of the Gadeb sites, their lithic assemblages were never published in detail, and no review of the stone tools has ever been reported since the original 1970s study. This paper updates the information available on Gadeb by presenting a systematic review of the lithic technology of several assemblages. The objectives are to evaluate the technological skills of Gadeb knappers and to contextualize them into the current discussion of the origins of the Acheulean and its possible coexistence with the so-called Developed Oldowan in East Africa.

  6. Holes in teeth - Dental caries in Neolithic and Early Bronze Age populations in Central Germany.

    PubMed

    Nicklisch, Nicole; Ganslmeier, Robert; Siebert, Angelina; Friederich, Susanne; Meller, Harald; Alt, Kurt W

    2016-01-01

    This study provides diachronic insight into the epidemiology of carious defects in teeth of Neolithic and Early Bronze Age populations in Central Germany over a period of 4000 years. The data were retrieved from skeletal remains uncovered at 21 sites throughout the Middle Elbe-Saale region (MES), comprising a total of 494 individuals with preserved teeth. The data generated were examined for age- and sex-related differences in order to gain information about the dietary habits and socio-economic structures of the period with the goal of identifying potential diachronic changes. The results indicated that dietary habits changed over the course of the Neolithic period: the prevalence of caries significantly decreased between the Early and Late Neolithic. The adults from the Early Neolithic sample, particularly those from the LBK bore the highest rate of caries. This highlights the essential importance of cereals in the diet of the early farmers in the Middle Elbe-Saale region. As time went on, meat and dairy products became more and more important, which had a positive impact on dental health. The data also show sex-specific differences: women were more often affected by caries than men and female jaws also generally exhibited greater numbers of carious teeth than their male counterparts. Dental health is a reflection of both biological factors and of economic and sociocultural structures. PMID:25765291

  7. Holes in teeth - Dental caries in Neolithic and Early Bronze Age populations in Central Germany.

    PubMed

    Nicklisch, Nicole; Ganslmeier, Robert; Siebert, Angelina; Friederich, Susanne; Meller, Harald; Alt, Kurt W

    2016-01-01

    This study provides diachronic insight into the epidemiology of carious defects in teeth of Neolithic and Early Bronze Age populations in Central Germany over a period of 4000 years. The data were retrieved from skeletal remains uncovered at 21 sites throughout the Middle Elbe-Saale region (MES), comprising a total of 494 individuals with preserved teeth. The data generated were examined for age- and sex-related differences in order to gain information about the dietary habits and socio-economic structures of the period with the goal of identifying potential diachronic changes. The results indicated that dietary habits changed over the course of the Neolithic period: the prevalence of caries significantly decreased between the Early and Late Neolithic. The adults from the Early Neolithic sample, particularly those from the LBK bore the highest rate of caries. This highlights the essential importance of cereals in the diet of the early farmers in the Middle Elbe-Saale region. As time went on, meat and dairy products became more and more important, which had a positive impact on dental health. The data also show sex-specific differences: women were more often affected by caries than men and female jaws also generally exhibited greater numbers of carious teeth than their male counterparts. Dental health is a reflection of both biological factors and of economic and sociocultural structures.

  8. The Impact of Early Age at First Childbirth on Maternal and Infant Health

    PubMed Central

    Gibbs, Cassandra M.; Wendt, Amanda; Peters, Stacey; Hogue, Carol J.

    2015-01-01

    The objective of this review was to assess whether early age at first childbirth is associated with increased risk of poor pregnancy outcomes. Early age at childbirth is variously defined in studies of its effect on maternal and infant health. In this systematic review, we limit analysis to studies of at least moderate quality that examine first births among young mothers, where young maternal age is defined as low gynaecological age (≤2 years since menarche) or as a chronological age ≤16 years at conception or delivery. We conduct meta-analyses for specific maternal or infant health outcomes when there are at least three moderate quality studies that define the exposure and outcome in a similar manner and provide odds ratios or risk ratios as their effect estimates. We conclude that the overall evidence of effect for very young maternal age (<15 years or <2 years post-menarche) on infant outcomes is moderate; that is, future studies are likely to refine the estimate of effect or precision but not to change the conclusion. Evidence points to an impact of young maternal age on low birthweight and preterm birth, which may mediate other infant outcomes such as neonatal mortality. The evidence that young maternal age increases risk for maternal anaemia is also fairly strong, although information on other nutritional outcomes and maternal morbidity/mortality is less clear. Many of the differences observed among older teenagers with respect to infant outcomes may be because of socio-economic or behavioural differences, although these may vary by country/ setting. Future, high quality observational studies in low income settings are recommended in order to address the question of generalisability of evidence. In particular, studies in low income countries need to consider low gynaecological age, rather than simply chronological age, as an exposure. As well, country-specific studies should measure the minimum age at which childbearing for teens has similar associations

  9. A Sample of Very Young Field L Dwarfs and Implications for the Brown Dwarf "Lithium Test" at Early Ages

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, J. Davy; Cruz, Kelle L.; Barman, Travis S.; Burgasser, Adam J.; Looper, Dagny L.; Tinney, C. G.; Gelino, Christopher R.; Lowrance, Patrick J.; Liebert, James; Carpenter, John M.; Hillenbrand, Lynne A.; Stauffer, John R.

    2008-12-01

    Using a large sample of optical spectra of late-type dwarfs, we identify a subset of late-M through L field dwarfs that, because of the presence of low-gravity features in their spectra, are believed to be unusually young. From a combined sample of 303 field L dwarfs, we find observationally that 7.6% +/- 1.6% are younger than 100 Myr. This percentage is in agreement with theoretical predictions once observing biases are taken into account. We find that these young L dwarfs tend to fall in the southern hemisphere (decl . < 0°) and may be previously unrecognized, low-mass members of nearby, young associations like Tucana-Horologium, TW Hydrae, β Pictoris, and AB Doradus. We use a homogeneously observed sample of ~150 optical spectra to examine lithium strength as a function of L/T spectral type and further corroborate the trends noted by Kirkpatrick and coworkers. We use our low-gravity spectra to investigate lithium strength as a function of age. The data weakly suggest that for early- to mid-L dwarfs the line strength reaches a maximum for a few × 100 Myr, whereas for much older (few Gyr) and much younger (<100 Myr) L dwarfs the line is weaker or undetectable. We show that a weakening of lithium at lower gravities is predicted by model atmosphere calculations, an effect partially corroborated by existing observational data. Larger samples containing L dwarfs of well-determined ages are needed to further test this empirically. If verified, this result would reinforce the caveat first cited by Kirkpatrick and coworkers that the lithium test should be used with caution when attempting to confirm the substellar nature of the youngest brown dwarfs. Most of the spectroscopic data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous

  10. Trajectories of Sleep Complaints From Early Midlife to Old Age: Longitudinal Modeling Study

    PubMed Central

    Salo, Paula; Vahtera, Jussi; Ferrie, Jane E.; Akbaraly, Tasnime; Goldberg, Marcel; Zins, Marie; Pentti, Jaana; Virtanen, Marianna; Shipley, Martin J.; Singh-Manoux, Archana; Dauvilliers, Yves; Kivimaki, Mika

    2012-01-01

    Study Objectives: To estimate trajectories of sleep lost over worry as a function of age, using longitudinal modeling, and compare these trajectories with those for insomnia symptoms. Design and Setting: Data from two prospective, occupational cohorts (the Whitehall II and Finnish Public Sector studies) comprising 84,384 observations from four to eight repeat measurements in 1985-2010. Participants: There were 16,408 men and women age 34-79 yr. Measurements and Results: Age-related trajectories of sleep lost over worry and insomnia symptoms (sleep initiation or maintenance problems, nonrefreshing sleep) were estimated using repeated-measures log-binomial regression analysis and generalized estimating equations. These analyses were adjusted for year of birth and time of measurement to minimize confounding by cohort or period effects. The prevalence ratio for insomnia symptoms was higher in older age groups compared with participants age 34-45 yr. In contrast, the age-related trajectory of sleep lost over worry included two phases: a period of high prevalence of sleep complaints at age 34-60 yr followed by a declining trajectory at older ages. Compared with participants age 34-45 yr, prevalence ratios for sleep lost over worry were 0.63 (0.49-0.80) and 0.59 (0.41-0.84) in the Whitehall II study participants ages 61-65 and 71-79 years. Corresponding figures were 0.62 (0.52-0.75) and 0.46 (0.32-0.66) in the Finnish Public Sector study. Conclusion: This study shows a general age-related decrease in sleep lost over worry between late midlife and old age, a pattern strikingly different from the age-related increase in insomnia symptoms. Citation: Salo P; Vahtera J; Ferrie JE; Akbaraly T; Goldberg M; Zins M; Pentti J; Virtanen M; Shipley MJ; Singh-Manoux A; Dauvilliers Y; Kivimaki M. Trajectories of sleep complaints from early midlife to old age: longitudinal modeling study. SLEEP 2012;35(11):1559-1568. PMID:23115405

  11. Early speech development, articulation and reading ability up to the age of 9.

    PubMed

    Luotonen, M

    1995-01-01

    Speech development, the occurrence of articulatory errors, speech therapy received and literacy were evaluated in children at preschool and school age. Data were obtained with questionnaires sent to the parents and teachers of 1,708 second-grade children in 119 school classes selected by multistage random sampling among Finnish-speaking schools throughout the country. Completed questionnaires were received from 1,531 parents (89.6%) and 1,601 teachers (93.7%). Early speech development was slower among the boys than among the girls. The proportion of children with articulatory errors decreased from 32.5% at the age of 5 years to 18.4% at 7 years and 7.4% at 9 years, and the boys had more articulation problems than the girls. Errors in two or more sounds at school age were rare, and more than 90% of all errors were in the sounds /r/, and /s/. About one fourth of the girls (26.7%) and one sixth of the boys (18.1%) had gained preschool literacy; 2.9% of the girls and 6.6% of the boys were still not able to read fluently by the middle of the fourth term. The difference between the sexes was seen both in the early development of speech and articulatory problems and in literacy at the age of 9. PMID:8868935

  12. Default Mode Network Activity Predicts Early Memory Decline in Healthy Young Adults Aged 18-31.

    PubMed

    Nelson, Steven M; Savalia, Neil K; Fishell, Andrew K; Gilmore, Adrian W; Zou, Fan; Balota, David A; McDermott, Kathleen B

    2016-08-01

    Functional magnetic resonance imaging (fMRI) research conducted in healthy young adults is typically done with the assumption that this sample is largely homogeneous. However, studies from cognitive psychology suggest that long-term memory and attentional control begin to diminish in the third decade of life. Here, 100 participants between the ages of 18 and 31 learned Lithuanian translations of English words in an individual differences study using fMRI. Long-term memory ability was operationalized for each participant by deriving a memory score from 3 convergent measures. Age of participant predicted memory score in this cohort. In addition, degree of deactivation during initial encoding in a set of regions occurring largely in the default mode network (DMN) predicted both age and memory score. The current study demonstrates that early memory decline may partially be accounted for by failure to modulate activity in the DMN.

  13. Homeostatic regulation of adult hippocampal neurogenesis in aging rats: long-term effects of early exercise

    PubMed Central

    Merkley, Christina M.; Jian, Charles; Mosa, Adam; Tan, Yao-Fang; Wojtowicz, J. Martin

    2014-01-01

    Adult neurogenesis is highly responsive to environmental and physiological factors. The majority of studies to date have examined short-term consequences of enhancing or blocking neurogenesis but long-term changes remain less well understood. Current evidence for age-related declines in neurogenesis warrant further investigation into these long-term changes. In this report we address the hypothesis that early life experience, such as a period of voluntary running in juvenile rats, can alter properties of adult neurogenesis for the remainder of the animal's life. The results indicate that the number of proliferating and differentiating neuronal precursors is not altered in runners beyond the initial weeks post-running, suggesting homeostatic regulation of these processes. However, the rate of neuronal maturation and survival during a 4 week period after cell division was enhanced up to 11 months of age (the end of the study period). This study is the first to show that a transient period of physical activity at a young age promotes changes in neurogenesis that persist over the long-term, which is important for our understanding of the modulation of neurogenesis by exercise with age. Functional integration of adult-born neurons within the hippocampus that resist homeostatic regulation with aging, rather than the absolute number of adult-born neurons, may be an essential feature of adult neurogenesis that promotes the maintenance of neural plasticity in old age. PMID:25071426

  14. Successful aging: the contribution of early-life and midlife risk factors

    PubMed Central

    Britton, Annie; Shipley, Martin; Singh-Manoux, Archana; Marmot, Michael G.

    2008-01-01

    Objectives To test whether early life factors (education, height, father’s social position) and midlife social, behavioral and psychosocial factors were associated with entering older age without disease and good functioning. Design A longitudinal, British civil service-based cohort study. Participants were followed for 17 years to assess successful aging. This was defined as being free of major disease and in the top tertile of physical and cognitive functioning measured in 2002–4. Setting Twenty London-based Civil Service departments Participants Four thousand, one hundred and forty men and 1823 women, free of major disease at baseline in 1985–8 (mean age 44, range 35–55 years) Measurements Behavioral, biological and psychosocial risk factors, physical and cognitive functioning and disease outcomes Results 548 (12.8%) men and 246 (14.6%) women were successfully aging at follow up. This was strongly predicted by midlife socioeconomic position (age adjusted odds ratio for men highest vs. lowest 7.06, 95% CI 3.4, 14.6). Height, education (men), not smoking, diet, exercise, moderate alcohol (women) and work support (men) were related to a favorable older life after adjustment for age and socioeconomic position. Conclusion Interventions to promote adult healthy behavior may attenuate harmful effects of less modifiable risk factors and reduce social inequalities. PMID:18482302

  15. The Effect of a Human Potential Lab Experience on Perceived Importance of Goals and Awareness of Strengths in Non-Traditional Aged Undergraduates

    ERIC Educational Resources Information Center

    Pickens, Bryon C.

    2013-01-01

    The purpose of this study was to examine the effect of a positively oriented group experience (human potential lab) on the awareness of personal strengths and perceived importance of goal setting in non-traditional aged undergraduates. The research questions that were posed were: 1) Does participation in the human potential lab experience increase…

  16. Early-Onset Thrombocytopenia in Small-For-Gestational-Age Neonates: A Retrospective Cohort Study.

    PubMed

    Fustolo-Gunnink, S F; Vlug, R D; Smits-Wintjens, V E H J; Heckman, E J; Te Pas, A B; Fijnvandraat, K; Lopriore, E

    2016-01-01

    Thrombocytopenia is a common finding in small for gestational age (SGA) neonates and is thought to result from a unique pathophysiologic mechanism related to chronic intrauterine hypoxia. Our objective was to estimate the incidence and severity of early-onset thrombocytopenia in SGA neonates, and to identify risk factors for thrombocytopenia. We performed a retrospective cohort study of all consecutive SGA neonates admitted to our ward and a control group of appropriate for gestational age (AGA) neonates matched for gestational age at birth. Main outcome measures were incidence and severity of thrombocytopenia, hematological and clinical risk factors for thrombocytopenia, and bleeding. A total of 330 SGA and 330 AGA neonates were included, with a mean gestational age at birth of 32.9 ± 4 weeks. Thrombocytopenia (<150x109/L) was found in 53% (176/329) of SGA neonates and 20% (66/330) of AGA neonates (relative risk (RR) 2.7, 95% confidence interval (CI) [2.1, 3.4]). Severe thrombocytopenia (21-50x109/L) occurred in 25 neonates (8%) in the SGA and 2 neonates (1%) in the AGA group (RR 12.5, 95% CI [3.0, 52.5]). Platelet counts <20x109/L were not recorded. Within the SGA group, lower gestational age at birth (p = <0.01) and erythroblastosis (p<0.01) were independently associated with a decrease in platelet count. Platelet count was positively correlated with birth weight centiles. In conclusion, early-onset thrombocytopenia is present in over 50% of SGA neonates and occurs 2.7 times as often as in AGA neonates. Thrombocytopenia is seldom severe and is independently associated with lower gestational age at birth and erythroblastosis. PMID:27177157

  17. Social inequality in walking speed in early old age in the Whitehall II study

    PubMed Central

    Brunner, Eric; Shipley, Martin; Spencer, Victoria; Kivimaki, Mika; Chandola, Tarani; Gimeno, David; Singh-Manoux, Archana; Guralnik, Jack; Marmot, Michael

    2009-01-01

    Background We investigated social inequalities in walking speed in early old age. Methods Walking speed was measured by 8 ft (2.44 m) timed test in 6345 individuals, mean (SD) age 61.1 (6.0) years. Current or last known Civil Service employment grade defined socioeconomic position. Results Mean (SD) walking speed was 1.36 (0.29) m/s in men and 1.21 (0.30) in women. Average age- and ethnicity-adjusted walking speed was approximately 13% higher in the highest employment grade compared to the lowest. Based on the relative index of inequality (RII), the difference in walking speed across the social hierarchy was 0.15 m/s (95% CI 0.12–0.18) in men and 0.17 (0.12–0.22) in women, corresponding to an age-related difference of 18.7 (13.6–23.8) years in men and 14.9 (9.9–19.9) years in women. The RII for slow walking speed (logistic model for lowest sex-specific quartile versus others) adjusted for age, sex and ethnicity was 3.40 (2.64–4.36). Explanatory factors for the social gradient in walking speed included SF-36 physical functioning, labor market status, financial insecurity, height and BMI. Demographic, psychosocial, behavioral, biological and health factors in combination accounted for 40% of social inequality in walking speed. Conclusions Social inequality in walking speed is substantial in early old age, and reflects many factors beyond the direct effects of physical health. PMID:19535784

  18. Early Predictors of Language and Social Communication Impairments at Ages 9-11 Years: A Follow-up Study of Early-Referred Children

    ERIC Educational Resources Information Center

    Chiat, Shula; Roy, Penny

    2013-01-01

    Purpose: In this study, the authors aimed to evaluate hypotheses that early sociocognition will predict later social communication and early phonology will predict later morphosyntax in clinically referred preschoolers. Method: Participants were 108 children ages 9-11 years who had been referred to clinical services with concerns about language at…

  19. Does the Amount of Fat Mass Predict Age-Related Loss of Lean Mass, Muscle Strength, and Muscle Quality in Older Adults?

    PubMed Central

    Ding, Jingzhong; Stenholm, Sari; Caserotti, Paolo; Houston, Denise K.; Nicklas, Barbara J.; You, Tongjian; Lee, Jung Sun; Visser, Marjolein; Newman, Anne B.; Schwartz, Ann V.; Cauley, Jane A.; Tylavsky, Frances A.; Goodpaster, Bret H.; Kritchevsky, Stephen B.; Harris, Tamara B.

    2011-01-01

    Background. An excessive amount of adipose tissue may contribute to sarcopenia and may be one mechanism underlying accelerated loss of muscle mass and strength with aging. We therefore examined the association of baseline total body fat with changes in leg lean mass, muscle strength, and muscle quality over 7 years of follow-up and whether this link was explained by adipocytokines and insulin resistance. Methods. Data were from 2,307 men and women, aged 70–79 years, participating in the Health, Aging, and Body Composition study. Total fat mass was acquired from dual energy X-ray absorptiometry. Leg lean mass was assessed by dual energy X-ray absorptiometry in Years 1, 2, 3, 4, 5, 6, and 8. Knee extension strength was measured by isokinetic dynamometer in Years 1, 2, 4, 6, and 8. Muscle quality was calculated as muscle strength divided by leg lean mass. Results. Every SD greater fat mass was related to 1.3 kg more leg lean mass at baseline in men and 1.5 kg in women (p < .01). Greater fat mass was also associated with a greater decline in leg lean mass in both men and women (0.02 kg/year, p < .01), which was not explained by higher levels of adipocytokines and insulin resistance. Larger fat mass was related to significantly greater muscle strength but significantly lower muscle quality at baseline (p < .01). No significant differences in decline of muscle strength and quality were found. Conclusions. High fatness was associated with lower muscle quality, and it predicts accelerated loss of lean mass. Prevention of greater fatness in old age may decrease the loss of lean mass and maintain muscle quality and thereby reducing disability and mobility impairments. PMID:21572082

  20. An Investigation of the Relationship between Psychological Strengths and the Perception of Bullying in Early Adolescents in Schools

    ERIC Educational Resources Information Center

    Anderson, Chris G.; Rawana, Edward P.; Brownlee, Keith; Whitley, Jessica

    2010-01-01

    This study explored the association between psychological strengths and perceptions of being a victim of a bullying relationship in the school environment. Using self-report questionnaires with grades 7 and 8 students, the role of psychological strengths as potential protective factors against various forms of bullying were examined including the…

  1. Lack of serotonin1B receptor expression leads to age-related motor dysfunction, early onset of brain molecular aging and reduced longevity

    PubMed Central

    Sibille, E; Su, J; Leman, S; Le Guisquet, AM; Ibarguen-Vargas, Y; Joeyen-Waldorf, J; Glorioso, C; Tseng, GC; Pezzone, M; Hen, R; Belzung, C

    2008-01-01

    Normal aging of the brain differs from pathological conditions and is associated with increased risk for psychiatric and neurological disorders. In addition to its role in the etiology and treatment of mood disorders, altered serotonin (5-HT) signaling is considered a contributing factor to aging; however, no causative role has been identified in aging. We hypothesized that a deregulation of the 5-HT system would reveal its contribution to age-related processes and investigated behavioral and molecular changes throughout adult life in mice lacking the regulatory presynaptic 5-HT1B receptor (5-HT1BR), a candidate gene for 5-HT-mediated age-related functions. We show that the lack of 5-HT1BR (Htr1bKO mice) induced an early age-related motor decline and resulted in decreased longevity. Analysis of life-long transcriptome changes revealed an early and global shift of the gene expression signature of aging in the brain of Htr1bKO mice. Moreover, molecular changes reached an apparent maximum effect at 18-months in Htr1bKO mice, corresponding to the onset of early death in that group. A comparative analysis with our previous characterization of aging in the human brain revealed a phylogenetic conservation of age-effect from mice to humans, and confirmed the early onset of molecular aging in Htr1bKO mice. Potential mechanisms appear independent of known central mechanisms (Bdnf, inflammation), but may include interactions with previously identified age-related systems (IGF-1, sirtuins). In summary, our findings suggest that the onset of age-related events can be influenced by altered 5-HT function, thus identifying 5-HT as a modulator of brain aging, and suggesting age-related consequences to chronic manipulation of 5-HT. PMID:17420766

  2. Metabolomic markers reveal novel pathways of ageing and early development in human populations

    PubMed Central

    Menni, Cristina; Kastenmüller, Gabriella; Petersen, Ann Kristin; Bell, Jordana T; Psatha, Maria; Tsai, Pei-Chien; Gieger, Christian; Schulz, Holger; Erte, Idil; John, Sally; Brosnan, M Julia; Wilson, Scott G; Tsaprouni, Loukia; Lim, Ee Mun; Stuckey, Bronwyn; Deloukas, Panos; Mohney, Robert; Suhre, Karsten; Spector, Tim D; Valdes, Ana M

    2013-01-01

    Background Human ageing is a complex, multifactorial process and early developmental factors affect health outcomes in old age. Methods Metabolomic profiling on fasting blood was carried out in 6055 individuals from the UK. Stepwise regression was performed to identify a panel of independent metabolites which could be used as a surrogate for age. We also investigated the association with birthweight overall and within identical discordant twins and with genome-wide methylation levels. Results We identified a panel of 22 metabolites which combined are strongly correlated with age (R2 = 59%) and with age-related clinical traits independently of age. One particular metabolite, C-glycosyl tryptophan (C-glyTrp), correlated strongly with age (beta = 0.03, SE = 0.001, P = 7.0 × 10−157) and lung function (FEV1 beta = −0.04, SE = 0.008, P = 1.8 × 10−8 adjusted for age and confounders) and was replicated in an independent population (n = 887). C-glyTrp was also associated with bone mineral density (beta = −0.01, SE = 0.002, P = 1.9 × 10−6) and birthweight (beta = −0.06, SE = 0.01, P = 2.5 × 10−9). The difference in C-glyTrp levels explained 9.4% of the variance in the difference in birthweight between monozygotic twins. An epigenome-wide association study in 172 individuals identified three CpG-sites, associated with levels of C-glyTrp (P < 2 × 10−6). We replicated one CpG site in the promoter of the WDR85 gene in an independent sample of 350 individuals (beta = −0.20, SE = 0.04, P = 2.9 × 10−8). WDR85 is a regulator of translation elongation factor 2, essential for protein synthesis in eukaryotes. Conclusions Our data illustrate how metabolomic profiling linked with epigenetic studies can identify some key molecular mechanisms potentially determined in early development that produce long-term physiological changes influencing human health and ageing. PMID:23838602

  3. Effect of water-ageing on dentine bond strength and anti-biofilm activity of bonding agent containing new monomer dimethylaminododecyl methacrylate

    PubMed Central

    Zhang, Ke; Cheng, Lei; Wu, Eric J.; Weir, Michael D.; Bai, Yuxing; Xu, Hockin H. K.

    2013-01-01

    Objectives The objectives of this study were to develop bonding agent containing a new antibacterial monomer dimethylaminododecyl methacrylate (DMADDM) as well as nanoparticles of silver (NAg) and nanoparticles of amorphous calcium phosphate (NACP), and to investigate the effects of water-ageing for 6 months on dentine bond strength and anti-biofilm properties for the first time. Methods Four bonding agents were tested: Scotchbond Multi-Purpose (SBMP) Primer and Adhesive control; SBMP + 5% DMADDM; SBMP + 5% DMADDM + 0.1% NAg; and SBMP + 5% DMADDM + 0.1% NAg with 20% NACP in adhesive. Specimens were water-aged for 1 d and 6 months at 37 °C. Then the dentine shear bond strengths were measured. A dental plaque microcosm biofilm model was used to inoculate bacteria on water-aged specimens and to measure metabolic activity, colony-forming units (CFUs), and lactic acid production. Results Dentine bond strength showed a 35% loss in 6 months of water-ageing for SBMP control (mean ± sd; n = 10); in contrast, the new antibacterial bonding agents showed no strength loss. The DMADDM–NAg–NACP containing bonding agent imparted a strong antibacterial effect by greatly reducing biofilm viability, metabolic activity and acid production. The biofilm CFU was reduced by more than two orders of magnitude, compared to SBMP control. Furthermore, the DMADDM–NAg–NACP bonding agent exhibited a long-term antibacterial performance, with no significant difference between 1 d and 6 months (p > 0.1). Conclusions Incorporating DMADDM–NAg–NACP in bonding agent yielded potent and long-lasting antibacterial properties, and much stronger bond strength after 6 months of water-ageing than a commercial control. The new antibacterial bonding agent is promising to inhibit biofilms and caries at the margins. The method of DMADDM–NAg–NACP incorporation may have a wide applicability to other adhesives, cements and composites. PMID:23583528

  4. Composition and depositional environment of concretionary strata of early Cenomanian (early Late Cretaceous) age, Johnson County, Wyoming

    USGS Publications Warehouse

    Merewether, E.A.; Gautier, Donald L.

    2000-01-01

    Unusual, concretion-bearing mudrocks of early Late Cretaceous age, which were deposited in an early Cenomanian epeiric sea, have been recognized at outcrops in eastern Wyoming and in adjoining areas of Montana, South Dakota, Nebraska, and Colorado. In Johnson County, Wyo., on the western flank of the Powder River Basin, these strata are in the lower part of the Belle Fourche Member of the Frontier Formation. At a core hole in south-central Johnson County, they are informally named Unit 2. These strata are about 34 m (110 ft) thick and consist mainly of medium- to dark-gray, noncalcareous, silty shale and clayey or sandy siltstone; and light-gray to grayish-red bentonite. The shale and siltstone are either bioturbated or interlaminated; the laminae are discontinuous, parallel, and even or wavy. Several ichnogenera of deposit feeders are common in the unit but filter feeders are sparse. The unit also contains marine and continental palynomorphs and, near the top, a few arenaceous foraminifers. No invertebrate macrofossils have been found in these rocks. Unit 2 conformably overlies lower Cenomanian shale in the lowermost Belle Fourche Member, informally named Unit 3, and is conformably overlain by lower and middle Cenomanian shale, siltstone, and sandstone within the member, which are informally named Unit 1. The mineral and chemical composition of the three Cenomanian units is comparable and similar to that of shale and siltstone in the Upper Cretaceous Pierre Shale, except that these units contain more SiO2 and less CaO, carbonate carbon, and manganese. Silica is generally more abundant and CaO is generally less abundant in river water than in seawater. The composition of Unit 2 contrasts significantly with that of the underlying and overlying units. Unit 2 contains no pyrite and dolomite and much less sulfur than Units 1 and 3. Sulfate is generally less abundant in river water than in seawater. Unit 2 also includes sideritic and calcitic concretions, whereas Units

  5. Sustained maintenance of exercise induced muscle strength gains and normal bone mineral density in patients with early rheumatoid arthritis: a 5 year follow up

    PubMed Central

    Hakkinen, A; Sokka, T; Kautiainen, H; Kotaniemi, A; Hannonen, P

    2004-01-01

    Objective: To investigate at 5 years whether an initial 2 year home based strength training period imposes sustained effects on muscle strength, bone mineral density (BMD), structural joint damage, and on disease activity in patients with early rheumatoid arthritis (RA). Methods: Seventy patients were randomised either to perform home based strength training with loads of 50–70% of repetition maximum (EG) or range of motion exercises (CG). Both groups were encouraged to take part in aerobic activities 2–3 times a week. Maximal muscle strength of different muscle groups was measured by dynamometers, and BMD at the femoral neck and lumbar spine by dual x ray densitometry. Disease activity was assessed by the 28 joint disease activity score, and joint damage by x ray findings. Results: 62 patients completed 2 years' training and 59 patients attended check up at 5 years. Mean (SD) maximum muscle strength indices increased from baseline to 2 years—in EG from 212 (78) kg by a mean (95% CI) of 68 (55 to 80) and in CG from 195 (72) kg by 35 (13 to 60) kg—and remained at that level for the next 3 years. Development of BMD in EG tended to be more favourable than that in CG. Muscle strength training was not detrimental to joint structures or disease activity. Conclusion: The patients' exercise induced muscle strength gains during a 2 year training period were maintained throughout a subsequent self monitored training period of 3 years. Despite substantial training effects in muscle strength, BMD values remained relatively constant. Radiographic damage remained low even at 5 years. PMID:15249317

  6. Use of weight-for-age-data to optimize tablet strength and dosing regimens for a new fixed-dose artesunate-amodiaquine combination for treating falciparum malaria.

    PubMed Central

    Taylor, Walter R. J.; Terlouw, Dianne J.; Olliaro, Piero L.; White, Nicholas J.; Brasseur, Philippe; ter Kuile, Feiko O.

    2006-01-01

    OBJECTIVE: To test a novel methodology to define age-based dosing regimens for the treatment of malaria with a new, user-friendly, blister-packaged fixed-dose combination of artesunate and amodiaquine. METHODS: A weight-for-age reference database of 88 054 individuals from sub-Saharan Africa was compiled using data from Demographic Health Surveys, observational and intervention studies, and standardized for sex, age and malaria risk. We then determined the optimal tablet strength (milligram (mg) per tablet) and age-dose categories for the combination of artesunate and amodiaquine. The proportions of patients predicted to receive doses within newly defined therapeutic ranges for amodiaquine (7-15 mg/kg/day) and artesunate (2-10 mg/kg/day), were estimated for different age categories and mg tablet strengths using models based on the weight-for-age reference database. FINDINGS: The optimal paediatric (p) and adult (a) strength tablets contained 25/67.5 and 100/270 mg artesunate/amodiaquine, respectively. A regimen with five age categories: 0-1 months (1/2 p), 2-11 months (1 p), 1-5 years (2 p), 6-13 years (1 a), and > 14 years (2 a) had an overall dosing accuracy of 83.4% and 99.9% for amodiaquine and artesunate, respectively. CONCLUSION: The proposed method to use weight-for-age reference data from countries where malaria is endemic is a useful tool for designing age-based dosing regimens for antimalarial drugs for drug registration and field use. PMID:17242831

  7. Early detection of aging cartilage and osteoarthritis in mice and patient samples using atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Stolz, Martin; Gottardi, Riccardo; Raiteri, Roberto; Miot, Sylvie; Martin, Ivan; Imer, Raphaël; Staufer, Urs; Raducanu, Aurelia; Düggelin, Marcel; Baschong, Werner; Daniels, A. U.; Friederich, Niklaus F.; Aszodi, Attila; Aebi, Ueli

    2009-03-01

    The pathological changes in osteoarthritis-a degenerative joint disease prevalent among older people-start at the molecular scale and spread to the higher levels of the architecture of articular cartilage to cause progressive and irreversible structural and functional damage. At present, there are no treatments to cure or attenuate the degradation of cartilage. Early detection and the ability to monitor the progression of osteoarthritis are therefore important for developing effective therapies. Here, we show that indentation-type atomic force microscopy can monitor age-related morphological and biomechanical changes in the hips of normal and osteoarthritic mice. Early damage in the cartilage of osteoarthritic patients undergoing hip or knee replacements could similarly be detected using this method. Changes due to aging and osteoarthritis are clearly depicted at the nanometre scale well before morphological changes can be observed using current diagnostic methods. Indentation-type atomic force microscopy may potentially be developed into a minimally invasive arthroscopic tool to diagnose the early onset of osteoarthritis in situ.

  8. Television viewing through ages 2-5 years and bullying involvement in early elementary school

    PubMed Central

    2014-01-01

    Background High television exposure time at young age has been described as a potential risk factor for developing behavioral problems. However, less is known about the effects of preschool television on subsequent bullying involvement. We examined the association between television viewing time through ages 2-5 and bullying involvement in the first grades of elementary school. We hypothesized that high television exposure increases the risk of bullying involvement. Method TV viewing time was assessed repeatedly in early childhood using parental report. To combine these repeated assessments we used latent class analysis. Four exposure classes were identified and labeled “low”, “mid-low”, “mid-high” and “high”. Bullying involvement was assessed by teacher questionnaire (n = 3423, mean age 6.8 years). Additionally, peer/self-report of bullying involvement was obtained using a peer nomination procedure (n = 1176, mean age 7.6 years). We examined child risk of being a bully, victim or a bully-victim (compared to being uninvolved in bullying). Results High television exposure class was associated with elevated risks of bullying and victimization. Also, in both teacher- and child-reported data, children in the high television exposure class were more likely to be a bully-victim (OR = 2.11, 95% CI: 1.42-3.13 and OR = 3.68, 95% CI: 1.75-7.74 respectively). However, all univariate effect estimates attenuated and were no longer statistically significant once adjusted for maternal and child covariates. Conclusions The association between television viewing time through ages 2-5 and bullying involvement in early elementary school is confounded by maternal and child socio-demographic characteristics. PMID:24520886

  9. Fatty acid composition of diets of early school-age children and its health implications

    PubMed Central

    Kostecka, Małgorzata

    2015-01-01

    Objective: The main objective of this study was to determine the amount and type of fat consumed by early school-age children per day. Dietary fat intake as a percentage of the total calorie intake was also estimated. Methods: The study was conducted in Lublin, the largest city in south-east Poland, between January 2014 and April 2014, on 702 randomly selected children, i.e. 3% of the total population of early school-age children in the research area. The parents were asked to provide information about the type and amount of food consumed by their children daily. A standard food frequency questionnaire was used. Results: Dietary levels of saturated fat were elevated in the analyzed populations and were the source of 13.33% of daily calorie intake. In the studied population, the ratio of saturated to monounsaturated and polyunsaturated fatty acids was determined at 3.25: 2.95: 1. Dietary intake of α-linolenic acid (ALA) reached 1.057 ± 0.55 g (0.63% of daily calorie intake) on average, and dietary intake of linoleic acid (LA) was determined at 3.86 ± 2.51 g (2.31% of daily calorie intake). Conclusions: The average total calorie intake of children aged 6-11 years was 1445.66 calories per day. Average fat intake was 29.64 % of the total calorie intake. The highest intake of SFAs was found in the youngest age group of 6- to 8-year-olds. The type of food consumed by children affected the amount and type of dietary fat in all age groups. PMID:26870117

  10. Age-26 Cost-Benefit Analysis of the Child-Parent Center Early Education Program

    PubMed Central

    Reynolds, Arthur J.; Temple, Judy A.; White, Barry A.; Ou, Suh-Ruu; Robertson, Dylan L.

    2013-01-01

    We conducted a cost-benefit analysis of the Child-Parent Center (CPC) early childhood intervention. Using data collected up to age 26 on health and well-being, the study is the first adult economic analysis of a sustained large-scale and publicly-funded intervention. As part of the Chicago Longitudinal Study, a complete cohort of 900 low-income children who enrolled in 20 CPCs beginning at age 3 were compared to 500 well-matched low-income children who participated in the usual educational interventions for the economically disadvantaged in Chicago schools. School-age services were provided up to age 9 (third grade). Findings indicated that the three components of CPC had economic benefits in 2007 dollars that exceeded costs. The preschool program provided a total return to society of $10.83 per dollar invested (net benefits per participant of $83,708). Benefits to the public (other than program participants and families) were $7.20 per dollar invested. The primary sources of benefits were increased earnings and tax revenues, averted criminal justice system and victim costs, and savings for child welfare, special education, and grade retention. The school-age program had a societal return of $3.97 per dollar invested and a $2.11 public return. The extended intervention program (4 to 6 years of participation) had a societal return of $8.24 and public return of $5.21. Estimates were robust across a wide range of discount rates and alternative assumptions, and were consistent with the results of Monte Carlo simulations. Males, 1-year preschool participants, and children from higher risk families had greater economic benefits. Findings provide strong evidence that sustained early childhood programs can contribute to well-being for individuals and society. PMID:21291448

  11. Early predictors of age at first use of alcohol, marijuana, and cigarettes.

    PubMed

    Fleming, J P; Kellam, S G; Brown, C H

    1982-08-01

    This paper is a report of the relationships between various measures of social adaptation to the first grade classroom and the age at which alcohol, cigarettes, and marijuana were first used by teenagers who began elementary school in a poor black urban community on the South Side of Chicago. Prospective longitudinal community epidemiological data were collected periodically in first and third grades from consecutive total cohorts of children in the 1960s. The 1966-67 population (cohort 3) was followed up at age 16 or 17. This population of 705 children is reported on here regarding early predictors of their first use of these substances. There are three main findings: (1) boys tended to use all substances at an earlier age than girls; (2) students who performed better on first grade IQ and Readiness tests tended to initiate substance use at an earlier age; (3) girls (but not boys) who were rated by their first grade teachers as shy or having learning problems tended to initiate use at a later age. The relationships of these findings to our past investigations of paths leading to substance use are discussed. PMID:6982159

  12. Being overweight in early adulthood is associated with increased mortality in middle age

    PubMed Central

    Carslake, David; Jeffreys, Mona; Davey Smith, George

    2016-01-01

    Observational analyses of the association between body mass index (BMI) and all-cause mortality often suggest that overweight is neutral or beneficial, but such analyses are potentially confounded by smoking or by reverse causation. The use of BMI measured in early adulthood offers one means of reducing the latter problem. We used a cohort who were first measured while 16–24 year old students at Glasgow University in 1948–1968 and subsequently re-measured in 2000–2003, offering a rare opportunity to compare BMI measured at different ages as a predictor of mortality. Analysis of the later BMI measurements suggested that overweight was beneficial to survival, while analysis of BMI measured in early adulthood suggested that overweight was harmful and that the optimum BMI lay towards the lower end of the recommended range of 18.5–25 kg m−2. We interpret the association with later BMI as being probably distorted by reverse causality, although it remains possible instead that the optimum BMI increases with age. Differences when analyses were restricted to healthy non-smokers also suggested some residual confounding by smoking. These results suggest that analyses of BMI recorded in middle or old age probably over-estimate the optimum BMI for survival and should be treated with caution. PMID:27782178

  13. Early Childhood Household Smoke Exposure Predicts Less Task-Oriented Classroom Behavior at Age 10.

    PubMed

    Pagani, Linda S; Fitzpatrick, Caroline

    2016-10-01

    Secondhand tobacco smoke is considered a developmental neurotoxicant especially given underdeveloped vital systems in young children. An ecological test of its negative influence on brain development can be made by examining the prospective association between early childhood household smoke exposure and later classroom behavior. Using a longitudinal birth cohort, we examined the unique contribution of household tobacco smoke exposure to children's subsequent classroom engagement at age 10. From child ages 1.5 to 7 years, parents of 2,055 participants from the Quebec Longitudinal Study of Child Development reported on household smoking by themselves and other home occupants. At age 10, fourth-grade teachers reported on the child's classroom engagement. In terms of prevalence, 58% of parents reported that their children were never exposed to smoke in the home, while 34% and 8% of children were exposed to transient and continuous household smoke, respectively. Compared with never exposed children, those who were exposed to transient and continuous household smoke scored 13% and 9% of a standard deviation lower on classroom engagement in fourth grade, standardized B = -.128 (95% confidence interval = -.186, -.069) and standardized B = -.093 (95% confidence interval = -.144, -.043), respectively. Compared with their never exposed peers, children exposed to transient and continuous early childhood household smoke showed proportionately less classroom engagement, which reflects task-orientation, following directions, and working well autonomously and with others. This predisposition poses risks for high school dropout, which from a population health perspective is closely linked with at-risk lifestyle habits and unhealthy outcomes.

  14. Poor physical function in elderly women in low-level aged care is related to muscle strength rather than to measures of sarcopenia

    PubMed Central

    Woods, Julie L; Iuliano-Burns, Sandra; King, Susannah J; Strauss, Boyd J; Walker, Karen Z

    2011-01-01

    Purpose: To determine the prevalence of sarcopenia and investigate relationships among body composition, muscle strength, and physical function in elderly women in low-level aged care. Subjects and methods: Sixty-three ambulatory women (mean age 86 years) participated in this cross-sectional study where body composition was determined by dual energy X-ray absorptiometry (DXA); ankle, knee, and hip strength by the Nicholas Manual Muscle Tester; and physical function by ‘timed up and go’ (TUG) and walking speed (WS) over 6 meters. Body composition data from a female reference group (n = 62, mean age 29 years) provided cut-off values for defining sarcopenia. Results: Elderly women had higher body mass index (P < 0.001), lower lean mass (P < 0.001), and higher fat mass (P < 0.01) than the young reference group. Only a small proportion (3.2%) had absolute sarcopenia (defined by appendicular skeletal muscle mass/height squared) whereas 37% had relative sarcopenia class II (defined by percentage skeletal muscle mass). Scores for TUG and WS indicated relatively poor physical function, yet these measures were not associated with muscle mass or indices of sarcopenia. In multivariate analysis, only hip abductor strength predicted both TUG and WS (both P = 0.01). Conclusion: Hip strength is a more important indicator of physical functioning than lean mass. Measurement of hip strength may therefore be a useful screening tool to detect those at risk of functional decline and requirement for additional care. Further longitudinal studies with a range of other strength measures are warranted. PMID:21472094

  15. Early Signs of Pathological Cognitive Aging in Mice Lacking High-Affinity Nicotinic Receptors

    PubMed Central

    Konsolaki, Eleni; Tsakanikas, Panagiotis; Polissidis, Alexia V.; Stamatakis, Antonios; Skaliora, Irini

    2016-01-01

    In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. A deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (β2-/-), which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioral signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviors, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm the hypothesis that β2-/- animals exhibit age-related cognitive impairments in spatial learning. In addition, they document age-related deficits in other areas, such as recognition memory, burrowing and nesting building, thereby extending the validity of this animal model for the study of pathological aging. Finally, our data reveal deficits in spontaneous behavior and habituation processes that precede the onset of cognitive decline and could therefore be useful as a non-invasive behavioral screen for identifying animals at risk. To our knowledge, this is the first study to perform an extensive behavioral assessment of an animal model of premature cognitive aging, and our results suggest that β2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioral changes to global dementia due to the combined effect of the neuropathology and aging. PMID:27199738

  16. Early Signs of Pathological Cognitive Aging in Mice Lacking High-Affinity Nicotinic Receptors.

    PubMed

    Konsolaki, Eleni; Tsakanikas, Panagiotis; Polissidis, Alexia V; Stamatakis, Antonios; Skaliora, Irini

    2016-01-01

    In order to address pathological cognitive decline effectively, it is critical to adopt early preventive measures in individuals considered at risk. It is therefore essential to develop approaches that identify such individuals before the onset of irreversible dementia. A deficient cholinergic system has been consistently implicated as one of the main factors associated with a heightened vulnerability to the aging process. In the present study we used mice lacking high affinity nicotinic receptors (β2-/-), which have been proposed as an animal model of accelerated/premature cognitive aging. Our aim was to identify behavioral signs that could serve as indicators or predictors of impending cognitive decline. We used test batteries in order to assess cognitive functions and additional tasks to investigate spontaneous behaviors, such as species-specific activities and exploration/locomotion in a novel environment. Our data confirm the hypothesis that β2-/- animals exhibit age-related cognitive impairments in spatial learning. In addition, they document age-related deficits in other areas, such as recognition memory, burrowing and nesting building, thereby extending the validity of this animal model for the study of pathological aging. Finally, our data reveal deficits in spontaneous behavior and habituation processes that precede the onset of cognitive decline and could therefore be useful as a non-invasive behavioral screen for identifying animals at risk. To our knowledge, this is the first study to perform an extensive behavioral assessment of an animal model of premature cognitive aging, and our results suggest that β2-nAChR dependent cognitive deterioration progressively evolves from initial subtle behavioral changes to global dementia due to the combined effect of the neuropathology and aging.

  17. Developmental Patterns of Social Trust between Early and Late Adolescence: Age and School Climate Effects

    PubMed Central

    Flanagan, Constance A.; Stout, Michael

    2010-01-01

    Social trust (i.e., beliefs that people are generally fair and trustworthy) is important to the functioning of democracies and trend studies show it has declined. We test hypotheses concerning the development of these beliefs in adolescence. Based on surveys of 1535 adolescents collected over two years, we find that middle and late adolescents had significantly lower levels of trust than early adolescents and that these beliefs became more stable and less related to interpersonal trust between early and late adolescence. Results of multiple group SEMs revealed that, regardless of age, adolescents’ reports that a strong sense of student solidarity characterized their school significantly increased ST at T2, controlling for levels at T1, and opportunities to exchange perspectives with fellow students increased ST at T2 indirectly, through feelings of student solidarity. The study points to the role of schools in nurturing the democratic dispositions of younger generations. PMID:20936077

  18. Insight on the anatomy, systematic relationships, and age of the Early Cretaceous ankylopollexian dinosaur Dakotadon lakotaensis

    PubMed Central

    Pagnac, Darrin C.

    2015-01-01

    Lakota Formation. Those data, combined with recently revised ages for the members of the Lakota Formation based on charophyte and ostracod biostratigraphy, constrain the age of this taxon to the late Valanginian to early Barremian. PMID:26417544

  19. Insight on the anatomy, systematic relationships, and age of the Early Cretaceous ankylopollexian dinosaur Dakotadon lakotaensis.

    PubMed

    Boyd, Clint A; Pagnac, Darrin C

    2015-01-01

    Lakota Formation. Those data, combined with recently revised ages for the members of the Lakota Formation based on charophyte and ostracod biostratigraphy, constrain the age of this taxon to the late Valanginian to early Barremian. PMID:26417544

  20. Phase angle and handgrip strength are sensitive early markers of energy intake in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition.

    PubMed

    Caccialanza, Riccardo; Cereda, Emanuele; Klersy, Catherine; Bonardi, Chiara; Cappello, Silvia; Quarleri, Lara; Turri, Annalisa; Montagna, Elisabetta; Iacona, Isabella; Valentino, Francesco; Pedrazzoli, Paolo

    2015-03-11

    The assessment of nutritional intakes during hospitalization is crucial, as it is known that nutritional status tends to worsen during the hospital stay, and this can lead to the negative consequences of malnutrition. International guidelines recommend the use of parenteral nutrition (PN) in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. However, to date, there are no published data regarding either energy intake or objective measurements associated with it in this patient population. The aim of the present exploratory methodological study was to evaluate whether phase angle (PhA) and handgrip strength normalized for skeletal muscle mass (HG/SMM) are sensitive early markers of energy intake in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. We evaluated 30 eligible patients, who were treated with personalized dietary modifications and supplemental PN for at least one week during hospitalization. In a liner regression model adjusted for age, gender, basal protein intake and the basal value of each variable, a trend toward improvement of PhA and preservation of HG/SMM was observed in patients satisfying the estimated calorie requirements (N = 20), while a significant deterioration of these parameters occurred in those who were not able to reach the target (N = 10). The mean adjusted difference and 95% CI were +1.4° (0.5-2.3) (p = 0.005) for PhA and +0.23 (0.20-0.43) (p = 0.033) for HG/SMM. A significant correlation between PhA and HG/SMM variations was also observed (r = 0.56 (95% CI, 0.23-0.77); p = 0.0023). PhA and HG/SMM were able to distinguish between hypophagic, non-surgical patients at nutritional risk who satisfied their estimated caloric requirements and those who did not after a one-week personalized nutritional support. Clinical studies are warranted, in order to verify these preliminary observations and to validate the role of PhA variations as early

  1. Early-age hydration and volume change of calcium sulfoaluminate cement-based binders

    NASA Astrophysics Data System (ADS)

    Chaunsali, Piyush

    Shrinkage cracking is a predominant deterioration mechanism in structures with high surface-to-volume ratio. One way to allay shrinkage-induced stresses is to use calcium sulfoaluminate (CSA) cement whose early-age expansion in restrained condition induces compressive stress that can be utilized to counter the tensile stresses due to shrinkage. In addition to enhancing the resistance against shrinkage cracking, CSA cement also has lower carbon footprint than that of Portland cement. This dissertation aims at improving the understanding of early-age volume change of CSA cement-based binders. For the first time, interaction between mineral admixtures (Class F fly ash, Class C fly ash, and silica fume) and OPC-CSA binder was studied. Various physico-chemical factors such as the hydration of ye'elimite (main component in CSA cement), amount of ettringite (the main phase responsible for expansion in CSA cement), supersaturation with respect to ettringite in cement pore solution, total pore volume, and material stiffness were monitored to examine early-age expansion characteristics. This research validated the crystallization stress theory by showing the presence of higher supersaturation level of ettringite, and therefore, higher crystallization stress in CSA cement-based binders. Supersaturation with respect to ettringite was found to increase with CSA dosage and external supply of gypsum. Mineral admixtures (MA) altered the expansion characteristics in OPC-CSA-MA binders with fixed CSA cement. This study reports that fly ash (FA) behaves differently depending on its phase composition. The Class C FA-based binder (OPC-CSA-CFA) ceased expanding beyond two days unlike other OPC-CSA-MA binders. Three factors were found to govern expansion of CSA cement-based binders: 1) volume fraction of ettringite in given pore volume, 2) saturation level of ettringite, and 3) dynamic modulus. Various models were utilized to estimate the macroscopic tensile stress in CSA cement

  2. Cone photopigment in older subjects: decreased optical density in early age-related macular degeneration

    NASA Astrophysics Data System (ADS)

    Elsner, Ann E.; Burns, Stephen A.; Weiter, John J.

    2002-01-01

    We measured changes to cone photoreceptors in patients with early age-related macular degeneration. The data of 53 patients were compared with normative data for color matching measurements of long- and middle-wavelength-sensitive cones in the central macula. A four-parameter model quantified cone photopigment optical density and kinetics. Cone photopigment optical density was on average less for the patients than for normal subjects and was uncorrelated with visual acuity. More light was needed to reduce the photopigment density by 50% in the steady state for patients. These results imply that cone photopigment optical density is reduced by factors other than slowed kinetics.

  3. Knowledge of the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages.

    PubMed

    Paraskevas, George K; Koutsouflianiotis, Konstantinos N; Nitsa, Zoi; Demesticha, Theano; Skandalakis, Panagiotis

    2016-01-01

    The evolution of knowledge regarding the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages is described, and general perceptions about this organ during different eras along this time line are presented. The original words of great physicians from the period of time stretching from Ancient Egypt to the Avicennan era are quoted and discussed to demonstrate how knowledge of the spleen has evolved and to present the theories that dominated each era. Furthermore, theories about illnesses relating to the spleen are reported, which show how this organ was perceived-in terms of its function and anatomy-during each era.

  4. Knowledge of the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages.

    PubMed

    Paraskevas, George K; Koutsouflianiotis, Konstantinos N; Nitsa, Zoi; Demesticha, Theano; Skandalakis, Panagiotis

    2016-01-01

    The evolution of knowledge regarding the anatomy and physiology of the spleen throughout Antiquity and the Early Middle Ages is described, and general perceptions about this organ during different eras along this time line are presented. The original words of great physicians from the period of time stretching from Ancient Egypt to the Avicennan era are quoted and discussed to demonstrate how knowledge of the spleen has evolved and to present the theories that dominated each era. Furthermore, theories about illnesses relating to the spleen are reported, which show how this organ was perceived-in terms of its function and anatomy-during each era. PMID:26507317

  5. Multiscale Predictors of Femoral Neck In Situ Strength in Aging Women: Contributions of BMD, Cortical Porosity, Reference Point Indentation, and Nonenzymatic Glycation.

    PubMed

    Abraham, Adam C; Agarwalla, Avinesh; Yadavalli, Aditya; McAndrew, Christopher; Liu, Jenny Y; Tang, Simon Y

    2015-12-01

    The diagnosis of fracture risk relies almost solely on quantifying bone mass, yet bone strength is governed by factors at multiple scales including composition and structure that contribute to fracture resistance. Furthermore, aging and conditions such as diabetes mellitus alter fracture incidence independently of bone mass. Therefore, it is critical to incorporate other factors that contribute to bone strength in order to improve diagnostic specificity of fracture risk. We examined the correlation between femoral neck fracture strength in aging female cadavers and areal bone mineral density, along with other clinically accessible measures of bone quality including whole-bone cortical porosity (Ct.Po), bone material mechanical behavior measured by reference point indentation (RPI), and accumulation of advanced glycation end-products (AGEs). All measurements were found to be significant predictors of femoral neck fracture strength, with areal bone mineral density (aBMD) being the single strongest correlate (aBMD: r = 0.755, p < 0.001; Ct.Po: r = -0.500, p < 0.001; RPI: r = -0.478, p < 0.001; AGEs: r = -0.336, p = 0.016). RPI-derived measurements were not correlated with tissue mineral density or local cortical porosity as confirmed by micro-computed tomography (μCT). Multiple reverse stepwise regression revealed that the inclusion of aBMD and any other factor significantly improve the prediction of bone strength over univariate predictions. Combining bone assays at multiple scales such as aBMD with tibial Ct.Po (r = 0.835; p < 0.001), tibial difference in indentation depth between the first and 20th cycle (IDI) (r = 0.883; p < 0.001), or tibial AGEs (r = 0.822; p < 0.001) significantly improves the prediction of femoral neck strength over any factor alone, suggesting that this personalized approach could greatly enhance bone strength and fracture risk assessment with the potential to guide clinical management

  6. Multiscale Predictors of Femoral Neck In Situ Strength in Aging Women: Contributions of BMD, Cortical Porosity, Reference Point Indentation, and Nonenzymatic Glycation

    PubMed Central

    Abraham, Adam C; Agarwalla, Avinesh; Yadavalli, Aditya; McAndrew, Christopher; Liu, Jenny Y; Tang, Simon Y

    2015-01-01

    The diagnosis of fracture risk relies almost solely on quantifying bone mass, yet bone strength is governed by factors at multiple scales including composition and structure that contribute to fracture resistance. Furthermore, aging and conditions such as diabetes mellitus alter fracture incidence independently of bone mass. Therefore, it is critical to incorporate other factors that contribute to bone strength in order to improve diagnostic specificity of fracture risk. We examined the correlation between femoral neck fracture strength in aging female cadavers and areal bone mineral density, along with other clinically accessible measures of bone quality including whole-bone cortical porosity (Ct.Po), bone material mechanical behavior measured by reference point indentation (RPI), and accumulation of advanced glycation end-products (AGEs). All measurements were found to be significant predictors of femoral neck fracture strength, with areal bone mineral density (aBMD) being the single strongest correlate (aBMD: r = 0.755, p < 0.001; Ct.Po: r = −0.500, p < 0.001; RPI: r = −0.478, p < 0.001; AGEs: r = −0.336, p = 0.016). RPI-derived measurements were not correlated with tissue mineral density or local cortical porosity as confirmed by micro–computed tomography (μCT). Multiple reverse stepwise regression revealed that the inclusion of aBMD and any other factor significantly improve the prediction of bone strength over univariate predictions. Combining bone assays at multiple scales such as aBMD with tibial Ct.Po (r = 0.835; p < 0.001), tibial difference in indentation depth between the first and 20th cycle (IDI) (r = 0.883; p < 0.001), or tibial AGEs (r = 0.822; p < 0.001) significantly improves the prediction of femoral neck strength over any factor alone, suggesting that this personalized approach could greatly enhance bone strength and fracture risk assessment with the potential to guide clinical management strategies for at-risk populations PMID:26060094

  7. Early injury of the neonatal lung contributes to premature lung aging: a hypothesis.

    PubMed

    Meiners, Silke; Hilgendorff, Anne

    2016-12-01

    Chronic lung disease of the newborn, also known as bronchopulmonary dysplasia (BPD), is the most common chronic lung disease in early infancy and results in an increased risk for long-lasting pulmonary impairment in the adult. BPD develops upon injury of the immature lung by oxygen toxicity, mechanical ventilation, and infections which trigger sustained inflammatory immune responses and extensive remodeling of the extracellular matrix together with dysregulated growth factor signaling. Histopathologically, BPD is characterized by impaired alveolarization, disrupted vascular development, and saccular wall fibrosis. Here, we explore the hypothesis that development of BPD involves disturbance of conserved pathways of molecular aging that may contribute to premature aging of the lung and an increased susceptibility to chronic lung diseases in adulthood. PMID:27406259

  8. Mid-Paleozoic age of granitoids in enclaves within early Cretaceous granulites, Fiordland, southwest New Zealand

    USGS Publications Warehouse

    Bradshaw, J.Y.; Kimbrough, D.L.

    1991-01-01

    Orthogneisses of granite, quartz monzonite, monzonite, and tonalite, occur locally as isolated enclaves within the Early Cretaceous granulite terrain (Western Fiordland Orthogneiss - WFO). Discordant U-Pb zircon isotopic data (seven fractions) from four granitoid samples from enclaves at George Sound, define an upper intecept age of 341??34 Ma that is interpreted as approximating the time of formation of the granitoid suite. The lower intercept age of 93??37 Ma is interpreted as approximating the time of zircon isotopic disturbance by major episodic Pb loss. The low 87Sr/ 86Sr initial ratio indicates that these mid-Paleozoic granitoids were derived from an isotopically primitive source. The granitoid enclaves within WFO show influences of several different sources. The granitoids provide evidence linking WFO to a mid-Palaeozoic country rock similar to the central Fiordland metasediments. -from Authors

  9. Evidence that a West-East admixed population lived in the Tarim Basin as early as the early Bronze Age

    PubMed Central

    2010-01-01

    Background The Tarim Basin, located on the ancient Silk Road, played a very important role in the history of human migration and cultural communications between the West and the East. However, both the exact period at which the relevant events occurred and the origins of the people in the area remain very obscure. In this paper, we present data from the analyses of both Y chromosomal and mitochondrial DNA (mtDNA) derived from human remains excavated from the Xiaohe cemetery, the oldest archeological site with human remains discovered in the Tarim Basin thus far. Results Mitochondrial DNA analysis showed that the Xiaohe people carried both the East Eurasian haplogroup (C) and the West Eurasian haplogroups (H and K), whereas Y chromosomal DNA analysis revealed only the West Eurasian haplogroup R1a1a in the male individuals. Conclusion Our results demonstrated that the Xiaohe people were an admixture from populations originating from both the West and the East, implying that the Tarim Basin had been occupied by an admixed population since the early Bronze Age. To our knowledge, this is the earliest genetic evidence of an admixed population settled in the Tarim Basin. PMID:20163704

  10. Relationship between Retinal Layer Thickness and the Visual Field in Early Age-Related Macular Degeneration

    PubMed Central

    Acton, Jennifer H.; Smith, R. Theodore; Hood, Donald C.; Greenstein, Vivienne C.

    2012-01-01

    Purpose. To quantify and compare the structural and functional changes in subjects with early age-related macular degeneration (AMD), using spectral-domain optical coherence tomography (SD-OCT) and microperimetry. Methods. Twenty-one eyes of 21 subjects with early AMD were examined. MP-1 10-2 visual fields (VFs) and SD-OCT line and detail volume scans were acquired. The thicknesses of the outer segment (OS; distance between inner segment ellipsoid band and upper retinal pigment epithelium [RPE] border) and RPE layers and elevation of the RPE from Bruch's membrane were measured using a computer-aided manual segmentation technique. Thickness values were compared with those for 15 controls, and values at locations with VF total deviation defects were compared with values at nondefect locations at equivalent eccentricities. Results. Sixteen of 21 eyes with AMD had VF defects. Compared with controls, line scans showed significant thinning of the OS layer (P = 0.006) and thickening and elevation of the RPE (P = 0.037, P = 0.002). The OS layer was significantly thinner in locations with VF defects compared with locations without defects (P = 0.003). There was a negligible difference between the retinal layer thickness values of the 5 eyes without VF defects and the values of normal controls. Conclusions. In early AMD, when VF defects were present, there was significant thinning of the OS layer and thickening and elevation of the RPE. OS layer thinning was significantly associated with decreased visual sensitivity, consistent with known photoreceptor loss in early AMD. For AMD subjects without VF defects, thickness values were normal. The results highlight the clinical utility of both SD-OCT retinal layer quantification and VF testing in early AMD. PMID:23074210

  11. The efficiency of attentional networks in early and late bilinguals: the role of age of acquisition.

    PubMed

    Tao, Lily; Marzecová, Anna; Taft, Marcus; Asanowicz, Dariusz; Wodniecka, Zofia

    2011-01-01

    Previous studies have demonstrated a bilingual advantage in the efficiency of executive attention. A question remains, however, about the impact of the age of L2 acquisition and relative balance of the two languages on the enhancement of executive functions in bilinguals, and whether this is modulated by the similarity of the bilingual's two languages. The present study explores these issues by comparing the efficiency of attentional networks amongst three groups of young adults living in Australia: English monolinguals and early and late Chinese-English bilinguals. We also address the impact of bilingualism on hemispheric lateralization of cognitive functions, which is of interest since a recent study on early bilinguals revealed reduced hemispheric asymmetry in attentional functioning. In the present study, participants performed a modified version of the lateralized attention network test. Both early and late bilinguals were found to have more efficient executive network than monolinguals. The late bilinguals, who were also reported to be more balanced in the proficiency and usage of their two languages, showed the greatest advantage in conflict resolution, whereas early bilinguals seemed to show enhanced monitoring processes. These group differences were observed when controlling for non-verbal intelligence and socioeconomic status. Such results suggest that specific factors of language experience may differentially influence the mechanisms of cognitive control. Since the bilinguals had distinct language sets, it seems that the influence of bilingualism on executive functions is present regardless of the similarity between the two languages. As for hemispheric lateralization, although the results were not clear-cut, they suggest the reduced lateralization in early bilinguals.

  12. Evolution of pancreas in aging: degenerative variation or early changes of disease?

    PubMed

    Chantarojanasiri, Tanyaporn; Hirooka, Yoshiki; Ratanachu-Ek, Thawee; Kawashima, Hiroki; Ohno, Eizaburo; Goto, Hidemi

    2015-04-01

    Pancreatic changes in aging have been described for many decades. They involve not only pancreatic parenchyma but also pancreatic ductal, microscopic, and exocrine functional changes. There have been many studies of these changes based on pathology and various imaging modalities, as well as functional studies. The pancreatic volume was found to decrease with advancing age, with a higher incidence of pancreatic steatosis, as demonstrated in autopsy and imaging studies. The pancreatic ductal structure has been described with wide ranges of normal variation, but many studies have shown a tendency toward enlargement with advancing age. By endoscopic ultrasound imaging, the aging pancreas may exhibit abnormal findings similar to chronic pancreatitis. Microscopically, there has been evidence of patchy lobular fibrosis and papillary hyperplasia and demonstrable k-ras mutation in both normal and dysplastic ductal mucosa. The evidence of pancreatic exocrine insufficiency has yielded conflicting results, but most studies have shown a tendency toward decreased pancreatic exocrine function in the elderly. Differentiating pancreatic change in the elderly from early chronic pancreatitis may be difficult as there are limited studies to compare these two conditions in terms of structural and functional changes.

  13. Resting-state fMRI evidence for early episodic memory consolidation: effects of age.

    PubMed

    Kukolja, Juraj; Göreci, D Yasemin; Onur, Özgür A; Riedl, Valentin; Fink, Gereon R

    2016-09-01

    Aging-related episodic memory decline is often attributed to insufficient encoding of new information, although the underlying neural processes remain elusive. We here tested the hypothesis that impaired memory consolidation contributes to aging-related memory decline. To this end, we used resting state functional magnetic resonance imaging in healthy young and older adults and investigated neural network connectivity underlying episodic memory consolidation and the effects of aging thereon. During postencoding rest, connectivity increased in subregions of temporobasal and temporo-occipital networks but decreased in a precuneal network. These connectivity changes predicted subsequent memory performance thereby constituting functional correlates of early memory consolidation. Furthermore, these consolidation-related regional connectivity changes partially overlapped with encoding-related neural activity changes, suggesting a close relationship between encoding- and consolidation-related activity. Older when compared to young participants failed to increase connectivity in the right lingual gyrus as part of an extended default mode network during consolidation, thereby providing a functional correlate for spatial contextual memory deficits. In conclusion, results are consistent with previous reports of persistent activity in regions mediating memory encoding as a core mechanism underlying episodic memory consolidation. Our data extend previous findings suggesting that aging-related memory decline results from a reduction of consolidation processes. PMID:27459940

  14. Modelling the ages and metallicities of early-type galaxies in Fundamental Plane space

    NASA Astrophysics Data System (ADS)

    Porter, L. A.; Somerville, R. S.; Primack, J. R.; Croton, D. J.; Covington, M. D.; Graves, G. J.; Faber, S. M.

    2014-12-01

    Recent observations have probed the formation histories of nearby elliptical galaxies by tracking correlations between the stellar population parameters, age and metallicity, and the structural parameters that enter the Fundamental Plane, size Re, and velocity dispersion σ. These studies have found intriguing correlations between these four parameters. In this work, we make use of a semi-analytic model, based on halo merger trees extracted from the Bolshoi cosmological simulation, that predicts the structural properties of spheroid-dominated galaxies based on an analytic model that has been tested and calibrated against an extensive suite of hydrodynamic+N-body binary merger simulations. We predict the Re, σ, luminosity, age, and metallicity of spheroid-dominated galaxies, enabling us to compare directly to observations. Our model predicts a strong correlation between age and σ for early-type galaxies, and no significant correlation between age and radius, in agreement with observations. In addition, we predict a strong correlation between metallicity and σ, and a weak correlation between metallicity and Re, in qualitative agreement with observations. We find that the correlations with σ arise as a result of the strong link between σ and the galaxy's assembly time. Minor mergers produce a large change in radius while leaving σ nearly the same, which explains the weaker trends with radius.

  15. Age-related changes in learning across early childhood: a new imitation task.

    PubMed

    Dickerson, Kelly; Gerhardstein, Peter; Zack, Elizabeth; Barr, Rachel

    2013-11-01

    Imitation plays a critical role in social and cognitive development, but the social learning mechanisms contributing to the development of imitation are not well understood. We developed a new imitation task designed to examine social learning mechanisms across the early childhood period. The new task involves assembly of abstract-shaped puzzle pieces in an arbitrary sequence on a magnet board. Additionally, we introduce a new scoring system that extends traditional goal-directed imitation scoring to include measures of both children's success at copying gestures (sliding the puzzle pieces) and goals (connecting the puzzle pieces). In Experiment 1, we demonstrated an age-invariant baseline from 1.5 to 3.5 years of age, accompanied by age-related changes in success at copying goals and gestures from a live demonstrator. In Experiment 2, we applied our new task to learning following a video demonstration. Imitation performance in the video demonstration group lagged behind that of the live demonstration group, showing a protracted video deficit effect. Across both experiments, children were more likely to copy gestures at earlier ages, suggesting mimicry, and only later copy both goals and gestures, suggesting imitation. Taken together, the findings suggest that different social learning strategies may predominate in imitation learning dependent upon the degree of object affordance, task novelty, and task complexity. PMID:22786801

  16. The influence of age, sex, bulb position, visual feedback, and the order of testing on maximum anterior and posterior tongue strength and endurance in healthy belgian adults.

    PubMed

    Vanderwegen, Jan; Guns, Cindy; Van Nuffelen, Gwen; Elen, Rik; De Bodt, Marc

    2013-06-01

    This study collected data on the maximum anterior and posterior tongue strength and endurance in 420 healthy Belgians across the adult life span to explore the influence of age, sex, bulb position, visual feedback, and order of testing. Measures were obtained using the Iowa Oral Performance Instrument (IOPI). Older participants (more than 70 years old) demonstrated significantly lower strength than younger persons at the anterior and the posterior tongue. Endurance remains stable throughout the major part of life. Gender influence remains significant but minor throughout life, with males showing higher pressures and longer endurance. The anterior part of the tongue has both higher strength and longer endurance than the posterior part. Mean maximum tongue pressures in this European population seem to be lower than American values and are closer to Asian results. The normative data can be used for objective assessment of tongue weakness and subsequent therapy planning of dysphagic patients. PMID:22983359

  17. Effect of various Portland cement paste compositions on early-age strain

    NASA Astrophysics Data System (ADS)

    Guzzetta, Alana G.

    Early-age strain in paste, mortar, and concrete mixtures was investigated using a new method where the specimen shape was a cone frustum. Strain of the specimen from both the horizontal and vertical directions was captured by height change measurement. The volumetric strain was then calculated as a function of the height change and was plotted versus time. A correlation was found between the slopes of the volumetric strain curve resulting from this test method and the initial setting time of the tested material. An initial evaluation of the repeatability of this innovative test method was conducted. The early-age strain effects of aggregate volume, shrinkage reducing admixture, water-cementitious ratio (w/cm), and partial cement replacement with supplementary cementitious materials were tested and individually compared. From these comparisons, it was observed that ambient temperature, bleed water development, and rheological properties had a significant impact on the volumetric strain results. Data showed increased strain as aggregate volume was reduced and as the w/cm was changed from 0.25 up to 0.50. The addition of shrinkage reducing admixture generally caused an increase in the 36-hour volumetric strain value. In most of the mixtures, cement replacement with 20% fly ash or 10% metakaolin reduced the measured volumetric strain when the w/cm was 0.30. Replacement of cement with 10% silica fume caused an insignificant change in volumetric strain results.

  18. Strategies for improving early detection and diagnosis of neovascular age-related macular degeneration

    PubMed Central

    Keane, Pearse A; de Salvo, Gabriella; Sim, Dawn A; Goverdhan, Srini; Agrawal, Rupesh; Tufail, Adnan

    2015-01-01

    Treatment of the neovascular form of age-related macular degeneration (AMD) has been revolutionized by the introduction of such agents as ranibizumab, bevacizumab, and aflibercept. As a result, the incidence of legal blindness occurring secondary to AMD has fallen dramatically in recent years in many countries. While these agents have undoubtedly been successful in reducing visual impairment and blindness, patients with neovascular AMD typically lose some vision over time, and often lose the ability to read, drive, or perform other important activities of daily living. Efforts are therefore under way to develop strategies that allow for earlier detection and treatment of this disease. In this review, we begin by providing an overview of the rationale for, and the benefits of, early detection and treatment of neovascular AMD. To achieve this, we begin by providing an overview of the pathophysiology and natural history of choroidal neovascularization, before reviewing the evidence from both clinical trials and “real-world” outcome studies. We continue by highlighting an area that is often overlooked: the importance of patient education and awareness for early AMD detection. We conclude the review by reviewing an array of both established and emerging technologies for early detection of choroidal neovascularization, ranging from Amsler chart testing, to hyperacuity testing, to advanced imaging techniques, such as optical coherence tomography. PMID:25733802

  19. Age Dating Merger Events in Early Type Galaxies via the Detection of AGB Light

    NASA Technical Reports Server (NTRS)

    Bothun, G.

    2005-01-01

    A thorough statistical analysis of the J-H vs. H-K color plane of all detected early type galaxies in the 2MASS catalog with velocities less than 5000 km/s has been performed. This all sky survey is not sensitive to one particular galactic environment and therefore a representative range of early type galaxy environments have been sampled. Virtually all N-body simulation so major mergers produces a central starburst due to rapid collection of gas. This central starburst is of sufficient amplitude to change the stellar population in the central regions of the galaxy. Intermediate age populations are given away by the presence of AGB stars which will drive the central colors redder in H-K relative to the J- H baseline. This color anomaly has a lifetime of 2-5 billion years depending on the amplitude of the initial starburst Employing this technique on the entire 2MASS sample (several hundred galaxies) reveals that the AGB signature occurs less than 1% of the time. This is a straightforward indication that virtually all nearby early type galaxies have not had a major merger occur within the last few billion years.

  20. Impact of Early Intervention on Psychopathology, Crime, and Weil-Being at Age 25

    PubMed Central

    2015-01-01

    Objective This randomized controlled trial tested the efficacy of early intervention to prevent adult psychopathology and improve well-being in early-starting conduct-problem children. Method Kindergarteners (N=9,594) in three cohorts (1991–1993) at 55 schools in four communities were screened for conduct problems, yielding 979 early starters. A total of 891 (91%) consented (51% African American, 47% European American; 69% boys). Children were randomly assigned by school cluster to a 10-year intervention or control. The intervention goal was to develop social competencies in children that would carry them throughout life, through social skills training, parent behavior-management training with home visiting, peer coaching, reading tutoring, and classroom social-emotional curricula. Manualization and supervision ensured program fidelity. Ninety-eight percent participated during grade 1, and 80% continued through grade 10. At age 25, arrest records were reviewed (N=817,92%), and condition-blinded adults psychiatrically interviewed participants (N=702; 81% of living participants) and a peer (N=535) knowledgeable about the participant. Results Intent-to-treat logistic regression analyses indicated that 69% of participants in the control arm displayed at least one externalizing, internalizing, or substance abuse psychiatric problem (based on self- or peer interview) at age 25, in contrast with 59% of those assigned to intervention (odds ratio=0.59, CI=0.43–0.81; number needed to treat=8). This pattern also held for self-interviews, peer interviews, scores using an “and” rule for self- and peer reports, and separate tests for externalizing problems, internalizing problems, and substance abuse problems, as well as for each of three cohorts, four sites, male participants, female participants, African Americans, European Americans, moderate-risk, and high-risk subgroups. Intervention participants also received lower severity-weighted violent (standardized estimate

  1. Early Childhood Precursors and School age Correlates of Different Internalising Problem Trajectories Among Young Children.

    PubMed

    Parkes, Alison; Sweeting, Helen; Wight, Daniel

    2016-10-01

    It is unclear why trajectories of internalising problems vary between groups of young children. This is the first attempt in the United Kingdom to identify and explain different trajectories of internalising problems from 46 to 94 months. Using both mother- and child-reported data from the large Growing Up in Scotland (GUS) birth cohort (N = 2901; male N = 1497, female N = 1404), we applied growth mixture modelling and multivariable multinomial regression models. Three trajectories were identified: low-stable, high-decreasing and medium-increasing. There were no gender differences in trajectory shape, membership, or importance of covariates. Children from both elevated trajectories shared several early risk factors (low income, poor maternal mental health, poor partner relationship, pre-school behaviour problems) and school-age covariates (low mother-child warmth and initial school maladjustment) and reported fewer supportive friendships at 94 months. However, there were also differences in covariates between the two elevated trajectories. Minority ethnic status and pre-school conduct problems were more strongly associated with the high-decreasing trajectory; and covariates measured after school entry (behaviour problems, mother-child conflict and school maladjustment) with the medium-increasing trajectory. This suggests a greater burden of early risk for the high-decreasing trajectory, and that children with moderate early problem levels were more vulnerable to influences after school transition. Our findings largely support the sparse existing international evidence and are strengthened by the use of child-reported data. They highlight the need to identify protective factors for children with moderate, as well as high, levels of internalising problems at pre-school age, but suggest different approaches may be required. PMID:26747450

  2. Predictors of Infant Age at Enrollment in Early Infant Diagnosis Services in Kenya.

    PubMed

    Goggin, Kathy; Wexler, Catherine; Nazir, Niaman; Staggs, Vincent S; Gautney, Brad; Okoth, Vincent; Khamadi, Samoel A; Ruff, Andrea; Sweat, Michael; Cheng, An-Lin; Finocchario-Kessler, Sarah

    2016-09-01

    Despite the importance of early detection to signal lifesaving treatment initiation for HIV+ infants, early infant diagnosis (EID) services have received considerably less attention than other aspects of prevention of mother to child transmission care. This study draws on baseline data from an on-going cluster randomized study of an intervention to improve EID services at six government hospitals across Kenya. Two logistic regressions examined potential predictors of "on time" (infant ≤6 weeks of age) vs. "late" (≥7 weeks) and "on time" versus "very late" (≥12 weeks) EID engagement among 756 mother-infant pairs. A quarter of the infants failed to get "on time" testing. Predictors of "on time" testing included being informed about EID by providers when pregnant, perceiving less HIV stigma, and mother's level of education. Predictors of "very late" testing (≥12 weeks of age) included not being informed about EID by providers when pregnant and living farther from services. Findings highlight the importance of ensuring that health care providers actively and repeatedly inform HIV+ mothers of the availability of EID services, reduce stigma by frequently communicating judgment free support, and assisting mothers in early planning for accessing EID services. Extra care should be focused on engaging mothers with less formal education who are at increased risk for seeking "late" EID testing. This study offers clear targets for improving services so that all HIV-exposed infants can be properly engaged in EID services, thus increasing the potential for the best possible outcomes for this vulnerable population. PMID:27108002

  3. Caregivers' Experience during Their Children's Transition Process from Early Childhood Special Education Services to School-Aged Special Education Services

    ERIC Educational Resources Information Center

    Hicks, Linda Yvonne

    2011-01-01

    This study investigates caregivers' perceptions of the transition process for children transitioning from Early Childhood Special Education (ECSE) to School Age Special Education services (SA). Interest in this topic developed during the researcher's 18 years of experience as an Itinerant Early Childhood Special Education Teacher during which she…

  4. Systemic, Integrated, and Sustainable Family Engagement across the Early Age Spectrum in San Mateo and Santa Clara Counties. Issue Brief

    ERIC Educational Resources Information Center

    Fehrer, Kendra

    2014-01-01

    A growing body of evidence indicates the critical importance of appropriate supports for children and their families at early ages, as well as the potential for targeted interventions to make meaningful contributions to children's development. Family involvement in the early years of a child's learning and development can serve as a protective…

  5. Early Pleistocene 40Ar/39Ar ages for Bapang Formation hominins, Central Jawa, Indonesia

    PubMed Central

    Larick, Roy; Ciochon, Russell L.; Zaim, Yahdi; Sudijono; Suminto; Rizal, Yan; Aziz, Fachroel; Reagan, Mark; Heizler, Matthew

    2001-01-01

    The Sangiran dome is the primary stratigraphic window for the Plio-Pleistocene deposits of the Solo basin of Central Jawa. The dome has yielded nearly 80 Homo erectus fossils, around 50 of which have known findspots. With a hornblende 40Ar/39Ar plateau age of 1.66 ± 0.04 mega-annum (Ma) reportedly associated with two fossils [Swisher, C.C., III, Curtis, G. H., Jacob, T., Getty, A. G., Suprijo, A. & Widiasmoro (1994) Science 263, 1118–1121), the dome offers evidence that early Homo dispersed to East Asia during the earliest Pleistocene. Unfortunately, the hornblende pumice was sampled at Jokotingkir Hill, a central locality with complex lithostratigraphic deformation and dubious specimen provenance. To address the antiquity of Sangiran H. erectus more systematically, we investigate the sedimentary framework and hornblende 40Ar/39Ar age for volcanic deposits in the southeast quadrant of the dome. In this sector, Bapang (Kabuh) sediments have their largest exposure, least deformation, and most complete tephrostratigraphy. At five locations, we identify a sequence of sedimentary cycles in which H. erectus fossils are associated with epiclastic pumice. From sampled pumice, eight hornblende separates produced 40Ar/39Ar plateau ages ranging from 1.51 ± 0.08 Ma at the Bapang/Sangiran Formation contact, to 1.02 ± 0.06 Ma, at a point above the hominin-bearing sequence. The chronological sequence of 40Ar/39Ar ages follows stratigraphic order across the southeast quadrant. An intermediate level yielding four nearly complete crania has an age of about 1.25 Ma. PMID:11309488

  6. Early Thymus Involution--Manifestation of an Aging Program or a Program of Development?

    PubMed

    Khalyavkin, A V; Krut'ko, V N

    2015-12-01

    "I see no physical reason why it should not have been possible for life to construct ageless individuals", said Carl von Weizsacker in 1979 at the Conference on DNA. An obvious biological reason for senescence may be the action of a built-in aging program. Many gerontologists believe that early thymic involution is an argument in favor of the existence of such a program. On the other hand, this involution may be a result of the program of development rather than aging. According to the concepts of noninfectious immunology, the immune system of vertebrates is also designed for immune surveillance over initial tumor development and for tissue-specific regulation of cell proliferation both in ontogenesis and during physiological and reparative regeneration of organs and tissues. Natural anti-tissue autoantibodies are the main effectors of such regulation. Therefore, the number of inherited genes of the variable part of immunoglobulin (V-genes) is not less than the number of all proliferative-competent cell types (~100). For the same reason, the maximal rate of growth, which is usually observed in the prepubertal period, coincides with the maximal thymus index and the maximal number of immunoglobulin-secreting cells as well as the minimal force of mortality during ontogeny. Thus, the circa-pubertal beginning of thymic involution is probably caused by the programmed deceleration of the growth rate in ontogeny, and not by the early manifestation of an aging program. This approach allows us to understand the mechanism of the well-known antitumor effect of the regeneration process of the organ homologous to the tumor, and hence we can try to use it in practical oncology. PMID:26638688

  7. Geophysical prospection on an Early Iron Age Cult Site near Frankfurt/Oder, Germany

    NASA Astrophysics Data System (ADS)

    Ullrich, Burkart; Kaufmann, Georg; Beilke-Voigt, Ines

    2010-05-01

    The Free University of Berlin and the Humboldt University of Berlin hosts the excellence cluster 264 Topoi, "The Formation and Transformation of Space and Knowledge in Ancient Civilizations". The Excellence Cluster pursues the goal of researching the interdependence of space and knowledge in the civilizations of the Ancient Near East, the Mediterranean, and Black Sea region and parts of the Eurasian steppe from the 6th millennium BC to around AD 500. Within this excellence cluster, the project A-I-11 "Lossow near Frankfurt/Oder - An Early Iron Age Cult Site of the Ancient Peripheral Zone" examines the evolution of an important cult site in Central Europe. The castle mound of Lossow was built as a fortified settlement in the late Bronze Age (10th century B.C.). After a phase of around 200 years, a supra-regionally significant, early Iron Age cult centre developed on this site (8th-6th century B.C.). Several pieces of evidence indicate that the locality had a central-site character. Typical for the site are well-shapes shafts, filled with large amounts of human and animal bones. The shafts with a diameter of about 1 meter and a depth of about 5 to 7 meters are a great challenge to near surface geophysics. Here, geophysical methods (geomagnetic gradiometry, geoelectric imaging, georadar survey) have been used to obtain a large-scale conclusive picture of the sub-surface both within the castle mount and around the perimeter. While the magnetic results reveal numerous archaeological artefacts, geoelectric imaging decipers the subsurface structure of the site.

  8. Age-Related Declines in Early Sensory Memory: Identification of Rapid Auditory and Visual Stimulus Sequences

    PubMed Central

    Fogerty, Daniel; Humes, Larry E.; Busey, Thomas A.

    2016-01-01

    Age-related temporal-processing declines of rapidly presented sequences may involve contributions of sensory memory. This study investigated recall for rapidly presented auditory (vowel) and visual (letter) sequences presented at six different stimulus onset asynchronies (SOA) that spanned threshold SOAs for sequence identification. Younger, middle-aged, and older adults participated in all tasks. Results were investigated at both equivalent performance levels (i.e., SOA threshold) and at identical physical stimulus values (i.e., SOAs). For four-item sequences, results demonstrated best performance for the first and last items in the auditory sequences, but only the first item for visual sequences. For two-item sequences, adults identified the second vowel or letter significantly better than the first. Overall, when temporal-order performance was equated for each individual by testing at SOA thresholds, recall accuracy for each position across the age groups was highly similar. These results suggest that modality-specific processing declines of older adults primarily determine temporal-order performance for rapid sequences. However, there is some evidence for a second amodal processing decline in older adults related to early sensory memory for final items in a sequence. This selective deficit was observed particularly for longer sequence lengths and was not accounted for by temporal masking. PMID:27199737

  9. Age-Related Declines in Early Sensory Memory: Identification of Rapid Auditory and Visual Stimulus Sequences.

    PubMed

    Fogerty, Daniel; Humes, Larry E; Busey, Thomas A

    2016-01-01

    Age-related temporal-processing declines of rapidly presented sequences may involve contributions of sensory memory. This study investigated recall for rapidly presented auditory (vowel) and visual (letter) sequences presented at six different stimulus onset asynchronies (SOA) that spanned threshold SOAs for sequence identification. Younger, middle-aged, and older adults participated in all tasks. Results were investigated at both equivalent performance levels (i.e., SOA threshold) and at identical physical stimulus values (i.e., SOAs). For four-item sequences, results demonstrated best performance for the first and last items in the auditory sequences, but only the first item for visual sequences. For two-item sequences, adults identified the second vowel or letter significantly better than the first. Overall, when temporal-order performance was equated for each individual by testing at SOA thresholds, recall accuracy for each position across the age groups was highly similar. These results suggest that modality-specific processing declines of older adults primarily determine temporal-order performance for rapid sequences. However, there is some evidence for a second amodal processing decline in older adults related to early sensory memory for final items in a sequence. This selective deficit was observed particularly for longer sequence lengths and was not accounted for by temporal masking.

  10. Nonmarine stratigraphy of latest Cretaceous and early Tertiary age, southwestern New Mexico

    SciTech Connect

    Lawton, T.F.; Mack, G.H.; Lucas, S.G.; Kietzke, K.K. )

    1989-09-01

    Recent fossil collections from nonmarine strata at localities in southwestern New Mexico indicate that the Ringbone formation, as originally defined, comprises units separated by a major hiatus that is represented in the field by an angular unconformity. The lower unit has yielded (NMMNH locality 298) two anterior caudal vertebral centra, morphologically and metrically indistinguishable from those of the Late Cretaceous tyrannosaurids Albertosaurus and Daspletosaurus. These dinosaur fossils establish a late Campanian or Maastrichtian age for the unit, indicating its equivalence with the McRae Formation of south-central New Mexico and the Fort Crittenden Formation of southeastern Arizona. The unit is composed of approximately 1,000 m of sedimentary-clast conglomerate, arkose, volcanic litharenite, and gray shale; it thus appears to contain detritus from several different source areas. The younger unit has yielded a low-diversity ostracod fauna of Paleocene to early Eocene age. Diagnostic taxa from the assemblage include Pseudoeocypris pagei and Cypridea arvadensis. The age of this fauna suggests equivalence with the Love Ranch and Lobo Formations of southern New Mexico. The unit consists of approximately 350 m of interbedded red siltstone and boulder conglomerate derived from Lower Cretaceous strata overlain by a sequence of laminated shale and subordinate sandstone with a preserved thickness of 150 m.

  11. Age-Related Declines in Early Sensory Memory: Identification of Rapid Auditory and Visual Stimulus Sequences.

    PubMed

    Fogerty, Daniel; Humes, Larry E; Busey, Thomas A

    2016-01-01

    Age-related temporal-processing declines of rapidly presented sequences may involve contributions of sensory memory. This study investigated recall for rapidly presented auditory (vowel) and visual (letter) sequences presented at six different stimulus onset asynchronies (SOA) that spanned threshold SOAs for sequence identification. Younger, middle-aged, and older adults participated in all tasks. Results were investigated at both equivalent performance levels (i.e., SOA threshold) and at identical physical stimulus values (i.e., SOAs). For four-item sequences, results demonstrated best performance for the first and last items in the auditory sequences, but only the first item for visual sequences. For two-item sequences, adults identified the second vowel or letter significantly better than the first. Overall, when temporal-order performance was equated for each individual by testing at SOA thresholds, recall accuracy for each position across the age groups was highly similar. These results suggest that modality-specific processing declines of older adults primarily determine temporal-order performance for rapid sequences. However, there is some evidence for a second amodal processing decline in older adults related to early sensory memory for final items in a sequence. This selective deficit was observed particularly for longer sequence lengths and was not accounted for by temporal masking. PMID:27199737

  12. Early adulthood: an overlooked age group in national sodium reduction initiatives in South Korea

    PubMed Central

    Park, Sohyun; Lee, Jounghee; Kwon, Kwang-Il; Kim, Jong-Wook; Byun, Jae-Eon; Kang, Baeg-Won; Choi, Bo Youl

    2014-01-01

    BACKGROUND/OBJECTIVES South Korean's sodium consumption level is more than twice the upper limit level suggested by the WHO. Steep increases in the prevalence of hypertension and cardiovascular disease in Korea necessitate more effective sodium reduction programs. This study was conducted in order to compare sodium intake-related eating behaviors and key psychosocial factors according to age group and gender. SUBJECTS/METHODS Using an online survey, a total of 1,564 adults (20-59 years old) considered to be geographically representative of South Korea were recruited and surveyed. The major outcomes were perceived behaviors, knowledge, intentions, and self-efficacy related to sodium intake. RESULTS The results show that perceived behavior and level of self-efficacy related to low sodium consumption differed by age and gender. Female participants showed better behavior and intention towards low sodium intake than male counterparts. Young participants in their 20s showed the lowest intention to change their current sodium intake as well as lowest self-efficacy measures. CONCLUSIONS Future sodium reduction interventions should be developed with tailored messages targeting different age and gender groups. Specifically, interventions can be planned and implemented at the college level or for workers in their early career to increase their intention and self-efficacy as a means of preventing future health complications associated with high sodium intake. PMID:25489413

  13. Atomic structure of Cu-10. 9 at % Be alloys in the early stages of aging

    SciTech Connect

    Koo, Y.M.

    1987-01-01

    Diffuse x-ray scattering was employed to investigate the local atomic structure and static strains in a single crystal of a Cu-10.9 at. % Be alloy in the early stages of aging. In addition to these experiments, neutron elastic and inelastic scattering were obtained to investigate the phonon properties in the as-quenched state of this alloy. In the as-quenched state, there is a nearly regular array of small ellipsoidal Be clusters aligned along <100> directions (This produces the tweed contrast seen in TEM). The density of these clusters is 7.5 x 10/sup 26//m/sup 3/. The diffuse streaks seen in electron diffraction patterns are due largely to thermal diffuse scattering. Phonon-dispersion curves show no large differences from those of pure copper, except at (xi xi xi)/sub T/ zone boundary, where there is softening. This difference may be due to a Kohn anomaly. The elastic anisotropy of this alloy increases considerably with alloying, which probably leads to the plate-like GP zone morphology in subsequent aging treatments. The structure of the GP zones is a mixture of Be-rich single- and multi-layered zones. As aging proceeds, the zones grow in thickness.

  14. Mid-thigh cortical bone structural parameters, muscle mass and strength, and association with lower limb fractures in older men and women (AGES-Reykjavik Study).

    PubMed

    Johannesdottir, Fjola; Aspelund, Thor; Siggeirsdottir, Kristin; Jonsson, Brynjolfur Y; Mogensen, Brynjolfur; Sigurdsson, Sigurdur; Harris, Tamara B; Gudnason, Vilmundur G; Lang, Thomas F; Sigurdsson, Gunnar

    2012-05-01

    In a cross-sectional study we investigated the relationship between muscle and bone parameters in the mid-thigh in older people using data from a single axial computed tomographic section through the mid-thigh. Additionally, we studied the association of these variables with incident low-trauma lower limb fractures. A total of 3,762 older individuals (1,838 men and 1,924 women), aged 66-96 years, participants in the AGES-Reykjavik study, were studied. The total cross-sectional muscular area and knee extensor strength declined with age similarly in both sexes. Muscle parameters correlated most strongly with cortical area and total shaft area (adjusted for age, height, and weight) but explained <10 % of variability in those bone parameters. The increment in medullary area (MA) and buckling ratio (BR) with age was almost fourfold greater in women than men. The association between MA and muscle parameters was nonsignificant. During a median follow-up of 5.3 years, 113 women and 66 men sustained incident lower limb fractures. Small muscular area, low knee extensor strength, large MA, low cortical thickness, and high BR were significantly associated with fractures in both sexes. Our results show that bone and muscle loss proceed at different rates and with different gender patterns. PMID:22451219

  15. Mid-thigh cortical bone structural parameters, muscle mass and strength, and association with lower limb fractures in older men and women (AGES-Reykjavik Study).

    PubMed

    Johannesdottir, Fjola; Aspelund, Thor; Siggeirsdottir, Kristin; Jonsson, Brynjolfur Y; Mogensen, Brynjolfur; Sigurdsson, Sigurdur; Harris, Tamara B; Gudnason, Vilmundur G; Lang, Thomas F; Sigurdsson, Gunnar

    2012-05-01

    In a cross-sectional study we investigated the relationship between muscle and bone parameters in the mid-thigh in older people using data from a single axial computed tomographic section through the mid-thigh. Additionally, we studied the association of these variables with incident low-trauma lower limb fractures. A total of 3,762 older individuals (1,838 men and 1,924 women), aged 66-96 years, participants in the AGES-Reykjavik study, were studied. The total cross-sectional muscular area and knee extensor strength declined with age similarly in both sexes. Muscle parameters correlated most strongly with cortical area and total shaft area (adjusted for age, height, and weight) but explained <10 % of variability in those bone parameters. The increment in medullary area (MA) and buckling ratio (BR) with age was almost fourfold greater in women than men. The association between MA and muscle parameters was nonsignificant. During a median follow-up of 5.3 years, 113 women and 66 men sustained incident lower limb fractures. Small muscular area, low knee extensor strength, large MA, low cortical thickness, and high BR were significantly associated with fractures in both sexes. Our results show that bone and muscle loss proceed at different rates and with different gender patterns.

  16. Isotopic constraints on the age and early differentiation of the Earth.

    PubMed

    McCulloch, M T

    1996-03-01

    The Earth's age and early differentiation history are re-evaluated using updated isotopic constraints. From the most primitive terrestrial Pb isotopic compositions found at Isua Greenland, and the Pilbara of Western Australia, combined with precise geochronology of these localities, an age 4.49 +/- 0.02 Ga is obtained. This is interpreted as the mean age of core formation as U/Pb is fractionated due to sequestering of Pb into the Earth's core. The long-lived Rb-Sr isotopic system provides constraints on the time interval for the accretion of the Earth as Rb underwent significant depletion by volatile loss during accretion of the Earth or its precursor planetesimals. A primitive measured 87Sr/86Sr initial ratio of 0.700502 +/- 10 has been obtained for an early Archean (3.46 Ga) barite from the Pilbara Block of Western Australia. Using conservative models for the evolution of Rb/Sr in the early Archean mantle allows an estimate to be placed on the Earth's initial Sr ratio at approximately 4.50 Ga, of 0.69940 +/- 10. This is significantly higher than that measured for the Moon (0.69900 +/- 2) or in the achondrite, Angra dos Reis (0.69894 +/- 2) and for a Rb/Sr ratio of approximately 1/2 of chondrites corresponds to a mean age for accretion of the Earth of 4.48 + /- 0.04 Ga. The now extinct 146Sm-142Nd (T1/2(146)=103 l0(6)yrs) combined with the long-lived 147Sm-143Nd isotopic systematics can also be used to provide limits on the time of early differentiation of the Earth. High precision analyses of the oldest (3.8-3.9 Ga) Archean gneisses from Greenland (Amitsoq and Akilia gneisses), and Canada (Acasta gneiss) do not show measurable (> +/- l0ppm) variations of 142Nd, in contrast to the 33 ppm 142Nd excess reported for an Archean sample. The general lack of 142Nd variations, combined with the presence of highly positive epsilon 143 values (+4.0) at 3.9 Ga, indicates that the record of large-scale Sm/Nd fractionation events was not preserved in the early-Earth from 4

  17. Investigating the Structure of the WJ-III Cognitive in Early School Age through Two Exploratory Bifactor Analysis Procedures

    ERIC Educational Resources Information Center

    Dombrowski, Stefan C.

    2014-01-01

    Two exploratory bifactor methods (e.g., Schmid-Leiman [SL] and exploratory bifactor analysis [EBFA]) were used to investigate the structure of the Woodcock-Johnson III (WJ-III) Cognitive in early school age (age 6-8). The SL procedure is recognized by factor analysts as a preferred method for EBFA. Jennrich and Bentler recently developed an…

  18. Early Basaltic Volcanism and Late Heavy Bombardment on Vesta: U-Pb Ages of Small Zircons and Phosphates in Eucrites

    NASA Astrophysics Data System (ADS)

    Zhou, Q.; Yin, Q.-Z.; Bottke, B.; Claeys, P.; Li, X.-H.; Wu, F.-Y.; Li, Q.-L.; Liu, Y.; Tang, G.-Q.

    2011-03-01

    We report a new technique to determine U-Pb ages in very small zircons (<5 µm) and apatite in eucrites by the Cameca ims 1280 ion probe. The new apatite age for eucrites suggests late heavy bombardment may have started as early as 4.1 Ga.

  19. Age associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SUMMARY: This 3 year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of ...

  20. Associations between Family Relationships and Symptoms/Strengths at Kindergarten Age: What Is the Role of Children's Parental Representations?

    ERIC Educational Resources Information Center

    Stadelmann, Stephanie; Perren, Sonja; von Wyl, Agnes; von Klitzing, Kai

    2007-01-01

    Background: The quality of the family relationships plays an important role in the development of children's psychopathology and in their socio-emotional development. This longitudinal study aims to investigate whether family relationships are related to children's symptoms/strengths at kindergarten, and whether family relationships are predictors…

  1. Factors associated with early menarche: results from the French Health Behaviour in School-aged Children (HBSC) study

    PubMed Central

    2010-01-01

    Background Puberty is a transition period making physiological development a challenge adolescents have to face. Early pubertal development could be associated with higher risks of poor health. Our objective was to examine risk behaviours, physical and psychological determinants associated with early menarche (<11 years). Methods Early menarche was assessed in the Health Behaviour in School-aged Children French cross-sectional survey. Data were collected in 2006 by anonymous self-reported standardized questionnaire from a nationally representative sample of 1072 15 years old girls in school classrooms. Family environment, school experience, physical and psychological factors, risk behaviours (substance use and sexual initiation) were recorded. Logistic regression models were applied (analysing for crude and adjusted relationships between early menarche and risk behaviours controlled for family context). Results Median age at menarche was 13.0 years; 57 girls (5.3%) were early-matured. Controlled for familial environment, early menarche was associated with having had more than two life-drunkenness episodes (adjusted OR = 2.5 [1.3-4.6]), early sexual initiation (adjusted OR = 2.8 [1.3-6.0]) and overweight (adjusted OR = 7.3 [3.6-14.9]). Conclusion Early-maturing girls may affiliate with older adolescents, hence engage in risk behaviours linked to their appearance rather than their maturity level. Factors associated with early menarche highlight the need to focus attention on early-matured girls to prevent further health problems linked to risk behaviours. PMID:20353570

  2. A new age model for the early-middle Miocene in the North Alpine Foreland Basin

    NASA Astrophysics Data System (ADS)

    Reichenbacher, Bettina; Krijgsman, Wout; Pippèrr, Martina; Sant, Karin; Kirscher, Uwe

    2016-04-01

    The establishment of high-resolution age models for sedimentary successions is crucial for numerous research questions in the geosciences and related disciplines. Such models provide an absolute chronology that permits precise dating of depositional episodes and related processes such as mountain uplift or climate change. Recently, our work in the Miocene sediments of the North Alpine Foreland Basin (NAFB) has revealed a significantly younger age (16.6 Myr) for sediments that were thought to have been deposited 18 Myr ago. This implies that a fundamentally revised new age model is needed for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB (20 to 15-Myr). Our new data also indicate that previously published reconstructions of early-middle Miocene palaeogeography, sedimentation dynamics, mountain uplift and climate change in the NAFB all require a critical review and revision. Further, the time-span addressed is of special interest, since it encompasses the onset of a global warming phase. However, it appears that a fundamentally revised new age model for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB can only be achieved based on a 500 m deep drilling in the NAFB for which we currently seek collaboration partners to develop a grant application to the International Continental Deep Drilling Program (ICDP). Reference: Reichenbacher, B., W. Krijgsman, Y. Lataster, M. Pippèrr, C. G. C. Van Baak, L. Chang, D. Kälin, J. Jost, G. Doppler, D. Jung, J. Prieto, H. Abdul Aziz, M. Böhme, J. Garnish, U. Kirscher, and V. Bachtadse. 2013. A new magnetostratigraphic framework for the Lower Miocene (Burdigalian/Ottnangian, Karpatian) in the North Alpine Foreland Basin. Swiss Journal of Geosciences 106:309-334.

  3. [Water consumption in piglets weaned early at various ages and fed a liquid diet].

    PubMed

    Holub, A

    1991-07-01

    Water consumption was recorded in 72 piglets of the Lorge White breed, weaned either on the second, sixth, tenth day or on the fourteenth day of age, this parameter was followed till the age of four weeks. The piglets were kept individually in a thermoneutral zone and they received a milk diet with macronutrient content, similar to sow's milk and water content of from 78.47%. The diet was offered to suck nine times a day in two-hour intervals. The piglet age at weaning was found to influence significantly water intake. Daily water ingestion is higher in piglets separated from the sows at a younger age than in piglets weaned later on; it reaches as much as 29% in the first group, 26% in the second group, 28% and 20% of live weight in the third and fourth groups, respectively. If converted to the metabolic weight, the percentage is still higher: more than 40% in the first group at the end of the fourth week. Although the spans of weaning beginnings were always identical in particular groups of piglets (four days), the differences in the water consumption were not the same. The differences were smaller between the first and second group, and the third and fourth group, in comparison with those between the second and third group. This fact confirms previous general statements about the periodization of early postnatal life of piglets. The beginning of weaning of the first two groups belongs to the "suckling" period, while the beginning of weaning of the other groups is within the "weaning" period.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Berriasian (Early Cretaceous) radiometric ages from the Grindstone Creek Section, Sacramento Valley, California

    USGS Publications Warehouse

    Bralower, T.J.; Ludwig, K. R.; Obradovich, J.D.

    1990-01-01

    The Grindstone Creek Section, Glenn County, Northern California is a sequence of hemipelagic mudstone, siltstone and sandstone interbedded with concretionary limestone and a few thin tuffs and bentonites. Two tuffs have been collected from a narrow interval of this sequence and subjected to mineralogical and isotopic analyses. UPb isotopic analyses of zircon fractions from these volcanic horizons indicate an age of 137.1 + 1.6/-0.6 Ma. A detailed investigation has been conducted on the calcareous nannofossil stratigraphy of this section based on numerous samples with moderately preserved assemblages. The nannoflora is largely of Tethyan affinity, and allows direct correlation with the Berriasian stratotype section, with sections with published magnetostratigraphies and with a DSDP site drilled between known magnetic anomalies. The dated tuffs lie in the lower part of the upper Berriasian Cretarhabdus angustiforatus Zone (Assipetra infracretacea Subzone) and within the narrow range of Rhagodiscus nebulosus. At three different sections, this subzone can be correlated with M-sequence Polarity Zones M16 and M16n. An independent magnetostratigraphic correlation is provided at DSDP Site 387, drilled between anomalies M15 and M16, where basal sediments contain R. nebulosus. Buchia collected within a meter of the lower tuff lie within the B. uncitoides Zone which is Berriasian in age. The upper tuff level, which occurs 65 m above the lower tuff, is situated within the overlying B. pacifica Zone. This zone had previously been correlated with the early Valanginian, but is clearly also partly of Berriasian age based on nannofossil stratigraphy. Our results allow an estimate of the age of the Berriasian-Valanginian and Jurassic-Cretaceous boundaries of 135.1 Ma and 141.1 Ma, respectively, and these fall within the range of, but differ significantiy from, several published time-scales. ?? 1990.

  5. Early hardness and shear bond strength of dual-cure resin cement light cured through resin overlays with different dentin-layer thicknesses.

    PubMed

    Chang, H-S; Kim, J-W

    2014-01-01

    The purpose of this study was to investigate whether dentin-layer thickness of resin overlays could affect the early hardness and shear bond strength of dual-cure resin cement (DCRC, RelyX ARC) after light curing with light curing units (LCUs) of various power densities: Optilux 360 (360), Elipar Freelight 2 (FL2), and Elipar S10 (S10). Resin overlays were fabricated using an indirect composite resin (Sinfony) with a dentin layer, an enamel layer, and a translucent layer of 0.5 mm thickness each (0.5-0.5-0.5) or of 0.2 mm, 0.5 mm, and 0.8 mm thickness (0.2-0.5-0.8), respectively. The DCRC was light cured for 40 seconds through the overlays, and surface hardness and shear bond strength to bovine dentin were tested 10 minutes after the start of light curing. Surface hardness was higher when the DCRC was light cured through the 0.2-0.5-0.8 combination than when the DCRC was light cured through the 0.5-0.5-0.5 combination with all LCUs. The ratio of upper surface hardness of DCRC light cured through resin overlays relative to the upper surface hardness of DCRC light cured directly was more than 90% only when the DCRC was light cured with S10 through the 0.2-0.5-0.8 combination. The shear bond strength value was higher when the DCRC was light cured with S10 through the 0.2-0.5-0.8 combination than when light cured with S10 through the 0.5-0.5-0.5 combination. This study indicates that reducing the dentin-layer thickness while increasing the translucent-layer thickness of resin inlays can increase the photopolymerization of DCRC, thereby increasing the early bond strength of resin inlays to dentin.

  6. [Can age-dependent cognitive functions be measured? P300 potentials--concept of brain aging--early diagnosis of dementia processes].

    PubMed

    Kügler, C

    1996-10-10

    Event related P300 potentials as the electrophysiological substrate of cognitive functions, such as the stimulus processing time (P300 latencies) and visual attention capacity (P300 amplitudes) are suitable for the analysis of age-related changes in cognitive human brain functions. P300 investigations carried out in a total of 330 test subjects aged between 18 and 98 years, showed an overall slight prolongation of the P300 latencies by 10 ms for each decade, as well as a discrete reduction in the P300 amplitudes of 1 microV. To describe the relationship between the P300 parameters and chronological age, polynomial regression models are more suitable than linear functions. This means that in middle-age, P300 potentials change only slightly while, from about the age of 60 upwards, a noticeable acceleration in the P300 changes takes place. An interesting observation was the fact that the acceleration in the P300 latency increase occurred some 10 years earlier in women than in men, beginning in the early postmenopausal period. The polynomial course of the regression function for the age-dependence of P300 potentials might reflect the positive influence of socio-cultural factors on the aging of cognitive functions. The true extent of the age-related changes in cognitive functions, however, can be determined only with the aid of intra-individual longitudinal studies. This is of considerable importance for the early diagnosis of both metabolic and primarily degenerative encephalopathies.

  7. The combined effects of diet quality and physical activity on maintenance of muscle strength among diabetic older adults from the NuAge cohort.

    PubMed

    Rahi, Berna; Morais, José A; Dionne, Isabelle J; Gaudreau, Pierrette; Payette, Hélène; Shatenstein, Bryna

    2014-01-01

    Diabetic older adults are at a higher risk of muscle strength (MS) decline than their non-diabetic counterparts. Adequate protein and energy intakes and physical activity (PA) may preserve MS during aging. However, the role of diet quality (DQ) in MS maintenance is still unknown. This study aimed to determine the association between DQ - alone or combined with PA - and changes in MS over 3 years in diabetic participants aged 67 to 84 years at recruitment in a secondary analysis of the longitudinal observational NuAge study. Changes in handgrip, knee extensor and elbow flexor strengths were calculated as the difference between recruitment (T1) and after 3 years (T4) in 156 diabetic older adults. Baseline DQ was calculated from 3 non-consecutive 24-hour dietary recalls collected at T1 using the validated Canadian Healthy Eating Index (C-HEI). Change in PA was calculated from Physical Activity Scale for the Elderly (PASE) as PASE T4-PASE T1. Four combinations of variables were created: C-HEI<70 with PASE change either < or > median and C-HEI ≥ 70 with PASE change either < or > median. The association between these four categories and MS maintenance was evaluated using General Linear Modeling (GLM). Analyses were stratified by sex and controlled for covariates. Baseline DQ alone was not associated with MS maintenance. Baseline DQ combined with PASE change showed associations with crude and baseline adjusted handgrip strength (p=0.031, p=0.018) and crude and baseline adjusted elbow flexor change (p=0.028, p=0.017) in males only; no significant results were found for knee extensor strength in either males or females. While findings for females were inconclusive, results demonstrate that better adherence to dietary guidelines combined with a more active lifestyle may prevent MS decline among diabetic older males. Additional research is needed on a larger sample since generalization of these results is limited by the small sample size.

  8. Plant remains from an Early Iron Age well at Hajndl, Slovenia.

    PubMed

    Sostarić, Renata; Alegro, Antun; Hrsak, Vladimir; Stancić, Zvjezdana; Küster, Hansjörg

    2009-12-01

    The archaeobotanical samples analysed derive from a well-preserved well dated to the Early Iron Age (Hallstatt) according to pottery found in the sampled layers and on a radiocarbon dating (720-520 cal B.C.) of the wooden construction of the well. Cultivated plants (Panicum miliaceum, Linum usitatissimum, Papaver somniferum and Camelina sativa) were recorded in relatively small numbers whereas primary cereals are lacking. Together with quite a large number of accompanied weeds they suggest agriculture activities, but a mixture of weeds and ruderal plants was probably also growing inside the relatively large settlement complex and could have been included in the assemblages just by chance. The plant species composition indicates local vegetation developed under strong anthropogenic influence and on mainly moist and nitrogen-rich soils. Grassland plants and an almost complete lacking of tree and shrub species characteristic for the climax vegetation (deciduous mesophilous mixed forests) of the region also indicate at least local human activity.

  9. Influence of sodium borate on the early age hydration of calcium sulfoaluminate cement

    SciTech Connect

    Champenois, Jean-Baptiste; Dhoury, Mélanie; Cau Dit Coumes, Céline; Mercier, Cyrille; Revel, Bertrand; Le Bescop, Patrick; Damidot, Denis

    2015-04-15

    Calcium sulfoaluminate (CSA) cements are potential candidates for the conditioning of radioactive wastes with high sodium borate concentrations. This work thus investigates early age hydration of two CSA cements with different gypsum contents (0 to 20%) as a function of the mixing solution composition (borate and NaOH concentrations). Gypsum plays a key role in controlling the reactivity of cement. When the mixing solution is pure water, increasing the gypsum concentration accelerates cement hydration. However, the reverse is observed when the mixing solution contains sodium borate. Until gypsum exhaustion, the pore solution pH remains constant at ~ 10.8, and a poorly crystallized borate compound (ulexite) precipitates. A correlation is established between this transient precipitation and the hydration delay. Decreasing the gypsum content in the binder, or increasing the sodium content in the mixing solution, are two ways of reducing the stability of ulexite, thus decreasing the hydration delay.

  10. Anatomy and age estimation of an early blue whale (Balaenoptera musculus) fetus.

    PubMed

    Roston, Rachel A; Lickorish, David; Buchholtz, Emily A

    2013-04-01

    The external anatomy of a 130-mm blue whale fetus (Balaenoptera musculus) is described, and its internal anatomy is reconstructed noninvasively from microCT scans. The specimen lies developmentally at the junction of the embryonic and fetal periods. Similarly to the embryos of many odontocetes, it lacks a caudal fluke and dorsal fin, but it also exhibits an elongated rostrum, resorbed umbilical hernia, partially exposed cornea, and spatial separation of the anus and genitalia seen in early odontocete fetuses. Dermal ossification of the cranial bones has begun, but the endochondral skeleton is completely cartilaginous. The shape and position of the maxilla suggest that the earliest stages of anterior skull telescoping have begun, but there is no indication of occipital overlap posteriorly. The nasopharynx, larynx, and heart already display the distinctive morphology characteristic of Balaenoptera. This study develops a model of body length changes during blue whale development by integrating the large International Whaling Statistics (IWS) database, historical observations of blue whale migration and reproduction, and descriptions of fetal growth trends in other mammals. The model predicts an age of 65 days postconception for the specimen. The early developmental milestones of Balaenoptera mirror those of the odontocete Stenella to a remarkable extent, but the first appearance of the caudal fluke and dorsal fin are delayed relative to other morphological transitions. The accelerated prenatal growth characteristic of Balaenoptera occurs during fetal, not embryonic, development. PMID:23447333

  11. Does Raising the Early Retirement Age Increase Employment of Older Workers?

    PubMed

    Staubli, Stefan; Zweimüller, Josef

    2013-12-01

    Two pension reforms in Austria increased the early retirement age (ERA) from 60 to 62 for men and from 55 to 58.25 for women. We find that raising the ERA increased employment by 9.75 percentage points among affected men and by 11 percentage points among affected women. The reforms had large spillover effects on the unemployment insurance program but negligible effects on disability insurance claims. Specifically, unemployment increased by 12.5 percentage points among men and by 11.8 percentage points among women. The employment response was largest among high-wage and healthy workers, while low-wage and less healthy workers either continued to retire early via disability benefits or bridged the gap to the ERA via unemployment benefits. Taking spillover effects and additional tax revenues into account, we find that for a typical birth-year cohort a one year increase in the ERA resulted in a reduction of net government expenditures of 107 million euros for men and of 122 million euros for women. PMID:24319299

  12. Anatomy and age estimation of an early blue whale (Balaenoptera musculus) fetus.

    PubMed

    Roston, Rachel A; Lickorish, David; Buchholtz, Emily A

    2013-04-01

    The external anatomy of a 130-mm blue whale fetus (Balaenoptera musculus) is described, and its internal anatomy is reconstructed noninvasively from microCT scans. The specimen lies developmentally at the junction of the embryonic and fetal periods. Similarly to the embryos of many odontocetes, it lacks a caudal fluke and dorsal fin, but it also exhibits an elongated rostrum, resorbed umbilical hernia, partially exposed cornea, and spatial separation of the anus and genitalia seen in early odontocete fetuses. Dermal ossification of the cranial bones has begun, but the endochondral skeleton is completely cartilaginous. The shape and position of the maxilla suggest that the earliest stages of anterior skull telescoping have begun, but there is no indication of occipital overlap posteriorly. The nasopharynx, larynx, and heart already display the distinctive morphology characteristic of Balaenoptera. This study develops a model of body length changes during blue whale development by integrating the large International Whaling Statistics (IWS) database, historical observations of blue whale migration and reproduction, and descriptions of fetal growth trends in other mammals. The model predicts an age of 65 days postconception for the specimen. The early developmental milestones of Balaenoptera mirror those of the odontocete Stenella to a remarkable extent, but the first appearance of the caudal fluke and dorsal fin are delayed relative to other morphological transitions. The accelerated prenatal growth characteristic of Balaenoptera occurs during fetal, not embryonic, development.

  13. Tuberculosis in Late Neolithic-Early Copper Age human skeletal remains from Hungary.

    PubMed

    Pósa, Annamária; Maixner, Frank; Mende, Balázs Gusztáv; Köhler, Kitti; Osztás, Anett; Sola, Christophe; Dutour, Olivier; Masson, Muriel; Molnár, Erika; Pálfi, György; Zink, Albert

    2015-06-01

    Alsónyék-Bátaszék in Southern Hungary is one of the largest late Neolithic settlements and cemeteries excavated in Central Europe. In total, 2359 burials from the Late Neolithic - Early Copper Age Lengyel culture were found between 2006 and 2009 [1]. Anthropological investigations previously carried out on individuals from this site revealed an interesting paleopathological case of tuberculosis in the form of Pott's disease dated to the early 5(th) millennium BC. In this study, selected specimens from this osteoarcheological series were subjected to paleomicrobiological analysis to establish the presence of MTBC bacteria. As all individuals showing clear osteological signs of TB infection belonged to a single grave group, 38 individuals from this grave group were analysed. The sample included the case of Pott's disease as well as individuals both with and without osseous TB manifestations. The detection of TB DNA in the individual with Pott's disease provided further evidence for the occurrence of TB in Neolithic populations of Europe. Moreover, our molecular analysis indicated that several other individuals of the same grave group were also infected with TB, opening the possibility for further analyses of this unique Neolithic skeletal series.

  14. Tuberculosis in Late Neolithic-Early Copper Age human skeletal remains from Hungary.

    PubMed

    Pósa, Annamária; Maixner, Frank; Mende, Balázs Gusztáv; Köhler, Kitti; Osztás, Anett; Sola, Christophe; Dutour, Olivier; Masson, Muriel; Molnár, Erika; Pálfi, György; Zink, Albert

    2015-06-01

    Alsónyék-Bátaszék in Southern Hungary is one of the largest late Neolithic settlements and cemeteries excavated in Central Europe. In total, 2359 burials from the Late Neolithic - Early Copper Age Lengyel culture were found between 2006 and 2009 [1]. Anthropological investigations previously carried out on individuals from this site revealed an interesting paleopathological case of tuberculosis in the form of Pott's disease dated to the early 5(th) millennium BC. In this study, selected specimens from this osteoarcheological series were subjected to paleomicrobiological analysis to establish the presence of MTBC bacteria. As all individuals showing clear osteological signs of TB infection belonged to a single grave group, 38 individuals from this grave group were analysed. The sample included the case of Pott's disease as well as individuals both with and without osseous TB manifestations. The detection of TB DNA in the individual with Pott's disease provided further evidence for the occurrence of TB in Neolithic populations of Europe. Moreover, our molecular analysis indicated that several other individuals of the same grave group were also infected with TB, opening the possibility for further analyses of this unique Neolithic skeletal series. PMID:25857937

  15. Does Raising the Early Retirement Age Increase Employment of Older Workers?*

    PubMed Central

    Staubli, Stefan; Zweimüller, Josef

    2013-01-01

    Two pension reforms in Austria increased the early retirement age (ERA) from 60 to 62 for men and from 55 to 58.25 for women. We find that raising the ERA increased employment by 9.75 percentage points among affected men and by 11 percentage points among affected women. The reforms had large spillover effects on the unemployment insurance program but negligible effects on disability insurance claims. Specifically, unemployment increased by 12.5 percentage points among men and by 11.8 percentage points among women. The employment response was largest among high-wage and healthy workers, while low-wage and less healthy workers either continued to retire early via disability benefits or bridged the gap to the ERA via unemployment benefits. Taking spillover effects and additional tax revenues into account, we find that for a typical birth-year cohort a one year increase in the ERA resulted in a reduction of net government expenditures of 107 million euros for men and of 122 million euros for women. PMID:24319299

  16. HEART--the Hounslow Early Active Recovery Team: implementing an inclusive strength-based model of care for people with early psychosis.

    PubMed

    Kelly, J; Wellman, N; Sin, J

    2009-08-01

    In recent years in the UK, the National Health Service has made policy commitments to delivering mental health services based on recovery principles. In general though, the UK mental health service providers are in the early stages of implementing recovery principles and approaches in front-line services. This paper describes the work of the Hounslow Early Active Recovery Team (HEART), which has made substantial progress in placing recovery principles and approaches at the heart of the work of an early intervention for psychosis team working in an ethnically diverse area of West London. As evidence of the success of the HEART, in its first year and half, the team has achieved high levels of customer satisfaction with its work and a recent audit has revealed that 57% of respondents were in employment or education contrasting with the extremely high unemployment rates reported in several UK studies of people with serious mental health problems.

  17. Reliability of 1-Repetition Maximum Estimation for Upper and Lower Body Muscular Strength Measurement in Untrained Middle Aged Type 2 Diabetic Patients

    PubMed Central

    Abdul-Hameed, Unaise; Rangra, Prateek; Shareef, Mohd. Yakub; Hussain, Mohd. Ejaz

    2012-01-01

    Purpose The 1-repetition maximum (1-RM) test is the gold standard test for evaluating maximal dynamic strength of groups of muscles. However, safety of actual 1-RM testing is questionable in clinical situations such as type 2 diabetes (T2D), where an estimated 1-RM test is preferred. It is unclear if acceptable test retest reliability exists for the estimated 1-RM test in middle aged T2D patients. This study examined the reliability of the estimated 1-RM strength test in untrained middle aged T2D subjects. Methods Twenty five untrained diabetic males (n=19) and females (n=6) aged 40.7+0.4 years participated in the study. Participants undertook the first estimated 1-RM test for five exercises namely supine bench press, leg press, lateral pull, leg extension and seated biceps curls. A familiarisation session was provided three to five days before the first test. 1-RM was estimated for all participants by Brzycki 1-RM prediction equation. Another identical 1-RM estimation procedure occurred one week after first test. Intraclass correlation coefficients (ICC), paired t-test, standard error of measurement (SEM), Bland-Altman plots, and estimation of 95% CI were used to assess reliability. Results Test-retest reliability was excellent (ICC2,1=0.98-0.99) for all measurements with the highest for leg extension (ICC2,1=0.99). The SEM was lowest for lateral pull and leg extension exercises. Paired t-tests showed non-significant differences between the means of 2 sessions across three of five exercises. Conclusions The study findings suggest that estimation of 1-RM is reliable for upper and lower body muscular strength measurement in untrained middle aged T2D patients. PMID:23342225

  18. Small Changes, But Huge Impact? The Right Anterior Insula's Loss of Connection Strength during the Transition of Old to Very Old Age.

    PubMed

    Muller, Angela M; Mérillat, Susan; Jäncke, Lutz

    2016-01-01

    A major contribution to our understanding of the aging brain comes either from studies comparing young with older adults or from studies investigating pathological aging and using the healthy aging older adults as control group. In consequence, we know relatively well, what distinguishes young from old brains or pathological aging from healthy but that does not mean that we really understand the structural and functional transformations characterizing the healthy aging brain. By analyzing task-free fMRI data from a large cross-sectional sample of 186 older adults (mean age = 70.4, 97 female), we aimed to elucidate age-related changes in the intrinsically active functional architecture of the brain in our study group covering an age range from 65 to 85 years. First, we conducted an intrinsic connectivity contrast analysis (ICC) in order to detect the brain regions whose degree of connectedness was significantly correlated with increasing age. Secondly, using connectivity analyses we investigated how the clusters highlighted by the ICC analysis functionally related to the other major resting-state networks. The most important finding was the right anterior insula's loss of connectedness in the older participants of the study group because of the region's causal role in the switching from the task-negative to the task-positive state of the brain. Further, we found a higher functional dedifferentiation of two of the brain's major intrinsic connectivity networks, the DMN, and the cingulo-opercular network, caused by a reduction of functional connection strength, especially in the frontal regions. At last, we showed that all these age-related changes have the potential to impair older adult's performance of working memory tasks. PMID:27242508

  19. Small Changes, But Huge Impact? The Right Anterior Insula's Loss of Connection Strength during the Transition of Old to Very Old Age

    PubMed Central

    Muller, Angela M.; Mérillat, Susan; Jäncke, Lutz

    2016-01-01

    A major contribution to our understanding of the aging brain comes either from studies comparing young with older adults or from studies investigating pathological aging and using the healthy aging older adults as control group. In consequence, we know relatively well, what distinguishes young from old brains or pathological aging from healthy but that does not mean that we really understand the structural and functional transformations characterizing the healthy aging brain. By analyzing task-free fMRI data from a large cross-sectional sample of 186 older adults (mean age = 70.4, 97 female), we aimed to elucidate age-related changes in the intrinsically active functional architecture of the brain in our study group covering an age range from 65 to 85 years. First, we conducted an intrinsic connectivity contrast analysis (ICC) in order to detect the brain regions whose degree of connectedness was significantly correlated with increasing age. Secondly, using connectivity analyses we investigated how the clusters highlighted by the ICC analysis functionally related to the other major resting-state networks. The most important finding was the right anterior insula's loss of connectedness in the older participants of the study group because of the region's causal role in the switching from the task-negative to the task-positive state of the brain. Further, we found a higher functional dedifferentiation of two of the brain's major intrinsic connectivity networks, the DMN, and the cingulo-opercular network, caused by a reduction of functional connection strength, especially in the frontal regions. At last, we showed that all these age-related changes have the potential to impair older adult's performance of working memory tasks. PMID:27242508

  20. Chorioamnionitis and Early Childhood Outcomes among Extremely Low-Gestational-Age Neonates

    PubMed Central

    Pappas, Athina; Kendrick, Douglas E.; Shankaran, Seetha; Stoll, Barbara J.; Bell, Edward F.; Laptook, Abbott R.; Walsh, Michele C.; Das, Abhik; Hale, Ellen C.; Newman, Nancy S.; Higgins, Rosemary D.

    2014-01-01

    Importance Chorioamnionitis is strongly linked to preterm birth and to neonatal infection. The association between histological and clinical chorioamnionitis and cognitive, behavioral and neurodevelopmental outcomes among extremely preterm neonates is less clear. We evaluated the impact of chorioamnionitis on 18-22 month neurodevelopmental outcomes in a contemporary cohort of extremely preterm neonates. Objective To compare the neonatal and neurodevelopmental outcomes of three groups of extremely-low-gestational-age infants with increasing exposure to perinatal inflammation: no chorioamnionitis, histological chorioamnionitis alone, or histological plus clinical chorioamnionitis. Design Longitudinal observational study. Setting Sixteen centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Participants 2390 extremely preterm infants born <27 weeks' gestational age between January 1, 2006 and December 31, 2008 with placental histopathology and 18-22 months' corrected age follow-up data were eligible. Main exposure Chorioamnionitis Main Outcome Measures Outcomes included cerebral palsy, gross motor functional limitation, behavioral scores (according to the Brief Infant-Toddler Social and Emotional Assessment), cognitive and language scores (according to the Bayley Scales of Infant Development, 3rd-Edition) and composite measures of death/neurodevelopmental impairment. Multivariable logistic and linear regression models were developed to assess the association between chorioamnionitis and outcomes while controlling for important variables known at birth. Results Neonates exposed to chorioamnionitis had a lower gestational age (GA) and had higher rates of early-onset sepsis and severe periventricular-intraventricular hemorrhage as compared with unexposed neonates. In multivariable models evaluating death and neurodevelopmental outcomes, inclusion of gestational age in the model diminished the association

  1. Early discrimination of Atlantic salmon smolt age: Time course of the relative effectiveness of body size and shape

    USGS Publications Warehouse

    Pearlstein, J.H.; Letcher, B.H.; Obedzinski, M.

    2007-01-01

    The goal of this study was to test the relative effectiveness of morphological measurements and body size in predicting the smolt age of Atlantic salmon Salmo salar and to determine the time course of body size and shape differences between smolt ages. Analyses were conducted on age-0 to age-2 fish that were stocked as fry in the West Brook, Massachusetts and on laboratory-raised age-0 to age-1 fish. Using both body size and shape, we could partition the age-0 fish collected during fall into future early or late smolts, although the predictive ability of body shape was somewhat weaker than that of body size, especially in the laboratory. Classification success averaged 81% (size) and 79% (shape) in the field and 85% (size) and 73% (shape) in the laboratory. Despite differences in smolt age between the field and the laboratory, the relative timing of growth rate differences between future early and late smolts was similar in the field and the laboratory and peaked at 50-60% of development from fry to smolt. While body shape differed between early and late smolts well before smoltification, it did not improve classification based on size alone.

  2. Alterations in brain neurotrophic and glial factors following early age chronic methylphenidate and cocaine administration.

    PubMed

    Simchon-Tenenbaum, Yaarit; Weizman, Abraham; Rehavi, Moshe

    2015-04-01

    Attention deficit hyperactivity disorder (ADHD) overdiagnosis and a pharmacological attempt to increase cognitive performance, are the major causes for the frequent (ab)use of psychostimulants in non-ADHD individuals. Methylphenidate is a non-addictive psychostimulant, although its mode of action resembles that of cocaine, a well-known addictive and abused drug. Neuronal- and glial-derived growth factors play a major role in the development, maintenance and survival of neurons in the central nervous system. We hypothesized that methylphenidate and cocaine treatment affect the expression of such growth factors. Beginning on postnatal day (PND) 14, male Sprague Dawley rats were treated chronically with either cocaine or methylphenidate. The rats were examined behaviorally and biochemically at several time points (PND 35, 56, 70 and 90). On PND 56, rats treated with cocaine or methylphenidate from PND 14 through PND 35 exhibited increased hippocampal glial-cell derived neurotrophic factor (GDNF) mRNA levels, after 21 withdrawal days, compared to the saline-treated rats. We found a significant association between cocaine and methylphenidate treatments and age progression in the prefrontal protein expression of brain derived neurotrophic factor (BDNF). Neither treatments affected the behavioral parameters, although acute cocaine administration was associated with increased locomotor activity. It is possible that the increased hippocampal GDNF mRNA levels, may be relevant to the reduced rate of drug seeking behavior in ADHD adolescence that were maintained from childhood on methylphenidate. BDNF protein level increase with age, as well as following stimulant treatments at early age may be relevant to the neurobiology and pharmacotherapy of ADHD. PMID:25576963

  3. Alterations in brain neurotrophic and glial factors following early age chronic methylphenidate and cocaine administration.

    PubMed

    Simchon-Tenenbaum, Yaarit; Weizman, Abraham; Rehavi, Moshe

    2015-04-01

    Attention deficit hyperactivity disorder (ADHD) overdiagnosis and a pharmacological attempt to increase cognitive performance, are the major causes for the frequent (ab)use of psychostimulants in non-ADHD individuals. Methylphenidate is a non-addictive psychostimulant, although its mode of action resembles that of cocaine, a well-known addictive and abused drug. Neuronal- and glial-derived growth factors play a major role in the development, maintenance and survival of neurons in the central nervous system. We hypothesized that methylphenidate and cocaine treatment affect the expression of such growth factors. Beginning on postnatal day (PND) 14, male Sprague Dawley rats were treated chronically with either cocaine or methylphenidate. The rats were examined behaviorally and biochemically at several time points (PND 35, 56, 70 and 90). On PND 56, rats treated with cocaine or methylphenidate from PND 14 through PND 35 exhibited increased hippocampal glial-cell derived neurotrophic factor (GDNF) mRNA levels, after 21 withdrawal days, compared to the saline-treated rats. We found a significant association between cocaine and methylphenidate treatments and age progression in the prefrontal protein expression of brain derived neurotrophic factor (BDNF). Neither treatments affected the behavioral parameters, although acute cocaine administration was associated with increased locomotor activity. It is possible that the increased hippocampal GDNF mRNA levels, may be relevant to the reduced rate of drug seeking behavior in ADHD adolescence that were maintained from childhood on methylphenidate. BDNF protein level increase with age, as well as following stimulant treatments at early age may be relevant to the neurobiology and pharmacotherapy of ADHD.

  4. Macro-level Age Norms for the Timing of Sexual Initiation and Adolescents’ Early Sexual Initiation in 17 European Countries

    PubMed Central

    Madkour, Aubrey Spriggs; de Looze, Margaretha; Ma, Ping; Halpern, Carolyn Tucker; Farhat, Tilda; ter Bogt, Tom F. M.; Ehlinger, Virginie; Nic Gabhainn, Saoirse; Currie, Candace; Godeau, Emmanuelle

    2014-01-01

    Purpose To examine the relationship between country-level age norms for sexual initiation timing and early sexual initiation (ESI) among adolescent boys and girls. Methods Nationally-representative data from 17 countries that participated in the 2006/07 European Social Survey (ESS-3, n=33,092) and the 2005/06 Health Behaviour in School-Aged Children Study (HBSC, n=27,702) were analyzed. Age norms were measured as the average country-level response to an item asking the age at which ESS respondents believed someone is too young to have sexual intercourse. HBSC respondents (aged 14-16) self-reported age at sexual initiation which we defined as early (<15 years) or not (≥15 years or no initiation). Control variables included age, family affluence, perceived socioeconomic status, family living arrangement, substance use, school attachment, and country-level legal age of consent. Multivariable three-level logistic models with random intercepts were run separately by sex. Results In multivariable analyses, higher overall age norms were associated with reduced likelihood of ESI among girls (AOR 0.60, 95% CI 0.45-0.79); associations with ESI were stronger for parent cohort (ages 31-65) norms (AOR 0.37, 95% CI 0.23-0.58) than for peer cohort (ages 15-20) norms (AOR 0.60, 95% CI 0.49-0.74). For boys, overall norms were also significantly negatively associated with ESI (AOR 0.68, 95% CI 0.46-0.99), as were parent cohort norms (AOR 0.66, 95% CI 0.45-0.96). Peer cohort norms were not significantly related to boys’ ESI. Conclusion Macro-level cultural norms may impact adolescents’ sexual initiation timing. Research exploring the sexual health outcomes of early initiators in countries with contrasting age norms is warranted. PMID:24508092

  5. Age at Onset of DSM-IV Pathological Gambling in a Non-Treatment Sample: Early- versus Later-Onset

    PubMed Central

    Black, Donald W.; Shaw, Martha; Coryell, William; Crowe, Raymond; McCormick, Brett; Allen, Jeff

    2015-01-01

    Background Pathological gambling (PG) is a prevalent and impairing public health problem. In this study we assessed age at onset in men and women with PG and compared the demographic and clinical picture of early- vs. later-onset individuals. We also compared age at onset in PG subjects and their first-degree relatives with PG. Method Subjects with DSM-IV PG were recruited during the conduct of two non-treatment clinical studies. Subjects were evaluated with structured interviews and validated questionnaires. Early-onset was defined as PG starting prior to age 33 years. Results Age at onset of PG in the 255 subjects ranged from 8 to 80 years with a mean (SD) of 34.0 (15.3) years. Men had an earlier onset than women. 84% of all subjects with PG had developed the disorder by age 50 years. Early-onset subjects were more likely to be male, to prefer action games, and to have substance use disorders, antisocial personality disorder, attention deficit/hyperactivity disorder, trait impulsiveness, and social anxiety disorder. Later-onset was more common in women and was associated with a preference for slots and a history of sexual abuse. Conclusions Age at onset of PG is bimodal and differs for men and women. Early- and later-onset PG have important demographic and clinical differences. The implications of the findings are discussed. PMID:25956751

  6. Age-associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    PubMed Central

    Trombetti, A.; Reid, K. F.; Hars, M.; Herrmann, F. R.; Pasha, E.; Phillips, E. M.; Fielding, R. A.

    2016-01-01

    Summary This 3-year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of life. Our findings reinforce the importance of preserving muscle health with advancing age. Introduction The age-associated loss of skeletal muscle quantity and function are critical determinants of independent physical functioning in later life. Longitudinal studies investigating how decrements in muscle components of sarcopenia impact fear of falling (FoF) and quality of life (QoL) in older adults are lacking. Methods Twenty-six healthy older subjects (age, 74.1±3.7; Short Physical Performance Battery (SPPB) score ≥10) and 22 mobility-limited older subjects (age, 77.2±4.4; SPPB score ≥9) underwent evaluations of lower extremity muscle size and composition by computed tomography, strength and power, and physical performance at baseline and after 3-year follow-up. The Falls Efficacy Scale (FES) and Short Form-36 questionnaire (SF-36) were also administered at both timepoints to assess FoF and QoL, respectively. Results At 3-year follow-up, muscle cross-sectional area (CSA) (p<0.013) and power decreased (p<0.001), while intermuscular fat infiltration increased (p<0.001). These decrements were accompanied with a longer time to complete 400 m by 22±46 s (p<0.002). Using linear mixed-effects regression models, declines of muscle CSA, strength and power, and SPPB score were associated with increased FES score (p<0.05 for each model). Reduced physical component summary score of SF-36 over follow-up was independently associated with decreased SPPB score (p<0.020), muscle CSA (p<0.046), and increased 400 m walk time (p<0.003). Conclusions In older adults with and without mobility limitations, declining muscle mass, strength, power, and physical performance contribute

  7. Early bond strength of two resin cements to Y-TZP ceramic using MPS or MPS/4-META silanes.

    PubMed

    Ozcan, Mutlu; Cura, Cenk; Valandro, Luiz Felipe

    2011-01-01

    For cementation of yttrium-stabilized tetragonal zirconium polycrystal (Y-TZP) ceramic frameworks, protocols of surface-conditioning methods and available cements vary, resulting in confusion among clinicians regarding selection and effects of different conditioning methods on cement adhesion. This study evaluated the effect of two silanes (3-trimethoxysilylpropylmethacrylate (MPS) and 3-trimethoxysilylpropylmethacrylate/4-methacryloyloxyethyl trimellitate anhydride methyl methacrylate (MPS/4-META) on the adhesion of two resin-based cements (SuperBond and Panavia F 2.0) to Y-TZP ceramic and compared several protocols with those indicated by the manufacturer of each of these cements. Disks of Y-TZP ceramic (LAVA, 3M ESPE) (n = 60) were divided into six experimental groups (n = 10 per group) and treated as follows: (1) silica coating (SC) + MPS silane + SuperBond; (2) SC + MPS/4-META + silane + SuperBond); (3) SC + MPS silane + Panavia F 2.0); (4) SC + MPS/4-META silane + Panavia F 2.0); (5) no conditioning + MPS/4-META silane + Super-Bond (SuperBond instructions); and (6) 50-μm Al(2)O(3) conditioning + Panavia F 2.0 (Panavia F 2.0 instructions). The specimens were subjected to shear-bond testing after water storage at 37 °C for 3 months in the dark. Data were analyzed by analysis of variance and Tukey's HSD (α = 0.05). After silica coating, the mean bond strength of SuperBond cement was not significantly different between MPS and MPS/4-META silanes (20.2 ± 3.7 and 20.9 ± 1.6 MPa, respectively), but the mean bond strength of Panavia F 2.0 was significantly higher with MPS silane (24.4 ± 5.3 MPa) than with MPS/4-META (12.3 ± 1.4 MPa) (P < 0.001). The SuperBond manufacturer's instructions alone resulted in significantly higher bond strength (9.7 ± 3.1 MPa) than the Panavia F 2.0 manufacturer's instruction (0 MPa) (P < 0.001). When silica coating and silanization were used, both SuperBond and Panavia F 2.0 cements demonstrated higher bond strengths they did when

  8. Effect of composite surface treatment and aging on the bond strength between a core build-up composite and a luting agent

    PubMed Central

    COTES, Caroline; CARDOSO, Mayra; de MELO, Renata Marques; VALANDRO, Luiz Felipe; BOTTINO, Marco Antonio

    2015-01-01

    Objective The purpose of this study was to assess the influence of conditioning methods and thermocycling on the bond strength between composite core and resin cement. Material and Methods Eighty blocks (8×8×4 mm) were prepared with core build-up composite. The cementation surface was roughened with 120-grit carbide paper and the blocks were thermocycled (5,000 cycles, between 5°C and 55°C, with a 30 s dwell time in each bath). A layer of temporary luting agent was applied. After 24 h, the layer was removed, and the blocks were divided into five groups, according to surface treatment: (NT) No treatment (control); (SP) Grinding with 120-grit carbide paper; (AC) Etching with 37% phosphoric acid; (SC) Sandblasting with 30 mm SiO2 particles, silane application; (AO) Sandblasting with 50 mm Al2O3 particles, silane application. Two composite blocks were cemented to each other (n=8) and sectioned into sticks. Half of the specimens from each block were immediately tested for microtensile bond strength (µTBS), while the other half was subjected to storage for 6 months, thermocycling (12,000 cycles, between 5°C and 55°C, with a dwell time of 30 s in each bath) and µTBS test in a mechanical testing machine. Bond strength data were analyzed by repeated measures two-way ANOVA and Tukey test (α=0.05). Results The µTBS was significantly affected by surface treatment (p=0.007) and thermocycling (p=0.000). Before aging, the SP group presented higher bond strength when compared to NT and AC groups, whereas all the other groups were statistically similar. After aging, all the groups were statistically similar. SP submitted to thermocycling showed lower bond strength than SP without thermocycling. Conclusion Core composites should be roughened with a diamond bur before the luting process. Thermocycling tends to reduce the bond strength between composite and resin cement. PMID:25760269

  9. Mid-femoral and mid-tibial muscle cross-sectional area as predictors of tibial bone strength in middle-aged and older men.

    PubMed

    Rantalainen, T; Nikander, R; Kukuljan, S; Daly, R M

    2013-09-01

    While it is widely acknowledged that bones adapt to the site-specific prevalent loading environment, reasonable ways to estimate skeletal loads are not necessarily available. For long bone shafts, muscles acting to bend the bone may provide a more appropriate surrogate of the loading than muscles expected to cause compressive loads. Thus, the aim of this study was to investigate whether mid-thigh muscle cross-sectional area (CSA) was a better predictor of tibial mid-shaft bone strength than mid-tibia muscle CSA in middle aged and older men. 181 Caucasian men aged 50-79 years (mean±SD; 61±7 years) participated in this study. Mid-femoral and mid-tibial bone traits cortical area, density weighted polar moment of area and muscle CSA [cm(2)] were assessed with computed tomography. Tibial bone traits were positively associated with both the mid-femur (r=0.44 to 0.46, P<0.001) and the mid-tibia muscle CSA (r=0.35 to 0.37, P<0.001). Multivariate regression analysis, adjusting for age, weight, physical activity and femoral length, indicated that mid-femur muscle CSA predicted tibial mid-shaft bone strength indices better than mid-tibia muscle CSA. In conclusion, the association between a given skeletal site and functionally adjacent muscles may provide a meaningful probe of the site-specific effect of loading on bone. PMID:23989248

  10. Influence of multi-step heat treatments in creep age forming of 7075 aluminum alloy: Optimization for springback, strength and exfoliation corrosion

    SciTech Connect

    Arabi Jeshvaghani, R.; Zohdi, H.; Shahverdi, H.R.; Bozorg, M.; Hadavi, S.M.M.

    2012-11-15

    Multi-step heat treatments comprise of high temperature forming (150 Degree-Sign C/24 h plus 190 Degree-Sign C for several minutes) and subsequent low temperature forming (120 Degree-Sign C for 24 h) is developed in creep age forming of 7075 aluminum alloy to decrease springback and exfoliation corrosion susceptibility without reduction in tensile properties. The results show that the multi-step heat treatment gives the low springback and the best combination of exfoliation corrosion resistance and tensile strength. The lower springback is attributed to the dislocation recovery and more stress relaxation at higher temperature. Transmission electron microscopy observations show that corrosion resistance is improved due to the enlargement in the size and the inter-particle distance of the grain boundaries precipitates. Furthermore, the achievement of the high strength is related to the uniform distribution of ultrafine {eta} Prime precipitates within grains. - Highlights: Black-Right-Pointing-Pointer Creep age forming developed for manufacturing of aircraft wing panels by aluminum alloy. Black-Right-Pointing-Pointer A good combination of properties with minimal springback is required in this component. Black-Right-Pointing-Pointer This requirement can be improved through the appropriate heat treatments. Black-Right-Pointing-Pointer Multi-step cycles developed in creep age forming of AA7075 for improving of springback and properties. Black-Right-Pointing-Pointer Results indicate simultaneous enhancing the properties and shape accuracy (lower springback).

  11. Community factors shaping early age at first sex among adolescents in Burkina Faso, Ghana, Malawi, and Uganda.

    PubMed

    Stephenson, Rob; Simon, Calleen; Finneran, Catherine

    2014-06-01

    Using data from the National Survey of Adolescents (2004), we examine the community-level factors associated with early age at first sex among adolescents 14-19 years old in four African countries. Regression models are fitted separately by sex for each country for an outcome measuring early age at first sex, with a focus on community-level factors as potential influences of age on sexual debut. The community-level factors associated with adolescents' sexual debut vary widely by both country and gender. Community influences that emerge as risk or protective factors of early sexual debut include community levels of adolescent marriage, wealth, religious group affiliation, sex education, parental monitoring, reproductive health knowledge, media exposure, membership in adolescent social group, and use of alcohol. Results indicate the importance of context-specific understanding of adolescents' sexual behaviour and suggest how elements of place should be harnessed in the development of effective HIV and sexual health interventions.

  12. Community Factors Shaping Early Age at First Sex among Adolescents in Burkina Faso, Ghana, Malawi, and Uganda

    PubMed Central

    Simon, Calleen; Finneran, Catherine

    2014-01-01

    ABSTRACT Using data from the National Survey of Adolescents (2004), we examine the community-level factors associated with early age at first sex among adolescents 14-19 years old in four African countries. Regression models are fitted separately by sex for each country for an outcome measuring early age at first sex, with a focus on community-level factors as potential influences of age on sexual debut. The community-level factors associated with adolescents’ sexual debut vary widely by both country and gender. Community influences that emerge as risk or protective factors of early sexual debut include community levels of adolescent marriage, wealth, religious group affiliation, sex education, parental monitoring, reproductive health knowledge, media exposure, membership in adolescent social group, and use of alcohol. Results indicate the importance of context-specific understanding of adolescents’ sexual behaviour and suggest how elements of place should be harnessed in the development of effective HIV and sexual health interventions. PMID:25076654

  13. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya.

    PubMed

    Joordens, Josephine C A; Dupont-Nivet, Guillaume; Feibel, Craig S; Spoor, Fred; Sier, Mark J; van der Lubbe, Jeroen H J L; Nielsen, Trine Kellberg; Knul, Monika V; Davies, Gareth R; Vonhof, Hubert B

    2013-12-01

    To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (~20 kyr [thousands of years]) wet-dry climate cycles resolved by Sr isotope ratios, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained between 1.945 ± 0.004 and 2.058 ± 0.034 Ma, and thus older than previously estimated. The new ages are consistent with a temporal overlap of two species of early Homo that can be distinguished by their facial morphology. Further, our results show that in this time interval, hominins occurred throughout the wet-dry climate cycles, supporting the hypothesis that the lacustrine Turkana Basin was a refugium during regionally dry periods. By establishing the observed first appearance datum of a marine-derived stingray in UBU deposits at 2.058 ± 0.034 Ma, we show that at this time the Turkana Basin was hydrographically connected to the Indian Ocean, facilitating dispersal of fauna between these areas. From a biogeographical perspective, we propose that the Indian Ocean

  14. Reproduction and early-age survival of manatees at Blue Spring, Upper St. Johns River, Florida

    USGS Publications Warehouse

    O'Shea, Thomas J.; Hartley, W.C.; O'Shea, Thomas J.; Ackerman, B.B.; Percival, H. Franklin

    1995-01-01

    We summarize reproduction of adults and survival of calves and subadult Florida manatees (Trichechus manatus latirostris) that were identified in winter at Blue Spring on the upper St. Johns River in Florida. Some records span more than 20 years, but most are from 15-year continuous annual observations during winter 1978-79 through winter 1992-93. Fifty-seven, first-year calves were identified; 55 litter sizes were one, and one consisted oftwins (1.79% of all births). Sex ratios of first-year calves did notsignificantly differfrom 1:1. Based on 21 of35 sighted females (15 individuals) that appeared pregnant and returned with calves during the subsequent winter, we estimated an early (neonatal to about 6 months) calf survival of 0.600. Based on estimations with a minimum-number-known-alive method, calf survival from the first to the second winter was at least 0.822, and subadult survival was 0.903 to the third, 0.958 to the fourth, 1.00 to the fifth, and 1.00 to the sixth winters. Seven females were observed from year of birth to their first winter with a nursing calf; the mean age at parturition to the first calf that survived to the next winter was 5.4 + 0.98 (SD) years. The estimated ages at first conception ranged from 3 to 6 years. The proportion of adult pregnant females was 0.410/year. Weaning was not observed in winter. Intervals between births averaged 2.60 + 0.81 years. The pooled proportion of adult females nursing first-winter calves was 0.303; the proportion of adult females nursing calves of any age was 0.407. These values do not significantly differ from those ofmanatees from the Crystal River or Atlantic Coast study areas. Anecdotal accounts are provided that suggested the existence of a pseudo estrus, an 11 to 13-month gestation, suppression of parturition in winter, and giving birth in quiet backwaters and canals. A female from Blue Spring produced at least seven calves during the 22 years since first observed and died giving birth at an estimated

  15. Improved age control on early Homo fossils from the upper Burgi Member at Koobi Fora, Kenya.

    PubMed

    Joordens, Josephine C A; Dupont-Nivet, Guillaume; Feibel, Craig S; Spoor, Fred; Sier, Mark J; van der Lubbe, Jeroen H J L; Nielsen, Trine Kellberg; Knul, Monika V; Davies, Gareth R; Vonhof, Hubert B

    2013-12-01

    To address questions regarding the evolutionary origin, radiation and dispersal of the genus Homo, it is crucial to be able to place the occurrence of hominin fossils in a high-resolution chronological framework. The period around 2 Ma (millions of years ago) in eastern Africa is of particular interest as it is at this time that a more substantial fossil record of the genus Homo is first found. Here we combine magnetostratigraphy and strontium (Sr) isotope stratigraphy to improve age control on hominin-bearing upper Burgi (UBU) deposits in Areas 105 and 131 on the Karari Ridge in the eastern Turkana Basin (Kenya). We identify the base of the Olduvai subchron (bC2n) plus a short isolated interval of consistently normal polarity that we interpret to be the Pre-Olduvai event. Combined with precession-forced (~20 kyr [thousands of years]) wet-dry climate cycles resolved by Sr isotope ratios, the magnetostratigraphic data allow us to construct an age model for the UBU deposits. We provide detailed age constraints for 15 hominin fossils from Area 131, showing that key specimens such as cranium KNM-ER 1470, partial face KNM-ER 62000 and mandibles KNM-ER 1482, KNM-ER 1801, and KNM-ER 1802 can be constrained between 1.945 ± 0.004 and 2.058 ± 0.034 Ma, and thus older than previously estimated. The new ages are consistent with a temporal overlap of two species of early Homo that can be distinguished by their facial morphology. Further, our results show that in this time interval, hominins occurred throughout the wet-dry climate cycles, supporting the hypothesis that the lacustrine Turkana Basin was a refugium during regionally dry periods. By establishing the observed first appearance datum of a marine-derived stingray in UBU deposits at 2.058 ± 0.034 Ma, we show that at this time the Turkana Basin was hydrographically connected to the Indian Ocean, facilitating dispersal of fauna between these areas. From a biogeographical perspective, we propose that the Indian Ocean

  16. Climate hazards, adaptation and "resilience" of societies (early Little Ice Age, west of France).

    NASA Astrophysics Data System (ADS)

    Athimon, Emmanuelle; Maanan, Mohamed

    2016-04-01

    Over the past ten to fifteen years, climate hazards and adaptation have received more attention due to the current climate change. Climate historians have gathered strong evidence that the world's climate has evolved over the past millennium and one of the most significant changes took place during the Little Ice Age. Recently, a set of questions has emerged: what were the effects of the Little Ice Age on human's societies? How did humans adapt to these climate changes? How did they react to extreme weather-related events? Using examples of climate hazards from the West of France during the beginning of the Little Ice Age (xivth-xviith centuries) such as storms, flooding, drought, harsh winters, the poster aims at showing how the past societies can constitute a source of inspiration for present ones. Through schemas, this research exposes the system's rebound capacity, points out the importance of the historical depth in research on human's adaptation and resilience and shows the value of integrating a historical approach. It reveals that History contributes to the knowledge of the relationship between societies and climate hazards. Data on climate hazards and adaptation of societies stem from historical sources such as chronicles, diaries, books of accounts, records of cities repairs. To protect themselves and their goods, medieval and modern societies had developed specific skills, practices and strategies. From the xivth to the xviiith century, there is an increase of defense by dikes in the low Loire, as for example the construction of those amongst Longué and Ponts-de-Cé between the early xivth century and 1407. The French kingdom's authorities also tried increasingly to provide technical, material, logistical and fiscal support: for instance, during the winter 1564-1565, several bridges have been destroyed by a river flooding in Nantes. The King Charles IX then offered to people of Nantes part of the funds from taxes on the main activities such as the

  17. Relative sea-level change in the central Cyclades (Greece) since the Early Bronze Age

    NASA Astrophysics Data System (ADS)

    Draganits, E.

    2012-04-01

    The Aegean is a focus of important cultural achievements in Europe since the Neolithic period. The resulting abundance of archaeological remains, many of them below sea-level represent an advantageous area for the study of local relative sea-level change. We have carried out detailed mapping of Despotiko Island (SW of Antiparos) and its surrounding. Despotiko is situated almost exactly in the center of the Cyclades (as defined nowadays), more so than Delos, and therefore is very well suited for sea-level studies of the Cyclades. This beneficial location, combined with a spacious and protected bay, additionally may explain its former importance as stepping-stone in the Aegean Sea. The island is uninhabited at present, but Early Bronze Age settlement sites and graveyards as well as a large Archaic sanctuary proof its former importance. The sanctuary is situated on a gently northeast dipping slope in the northeast part of Despotiko, in range of sight of the Órmos Despotiko. Since 1997 large parts of this important sanctuary have been excavated during several excavation campaigns. Tectonically, Despotiko, Antiparos and Paros, belong to the Attic-Cycladic Crystalline of the Central Hellenides, a stack of metamorphic tectonic nappes, mainly comprising variable types of gneiss, schist, marble and amphibolite, and tectonic slices of unmetamorphosed sediments on top, separated by low-angle normal faults from the metamorphic units below. Submerged archaeological structures at the sea bottom of the Órmos Despotiko, a Classical marble inscription from the sanctuary and partly submerged agriculture trenches at the east coast Despotiko, indicate that the relative sea-level in this area was some 3 m lower during the Early Bronze Age and still more than 1 m lower during Classical time. These values of relative sea-level rise indicate a subsidence component additional to the global sea-level rise in the investigated time period. Neglecting possible vertical tectonic movements and

  18. Early child care and obesity at 12 months of age in the Danish National Birth Cohort

    PubMed Central

    Neelon, Sara E Benjamin; Andersen, Camilla Schou; Morgen, Camilla Schmidt; Kamper-Jørgensen, Mads; Oken, Emily; Gillman, Matthew W; Sørensen, Thorkild IA

    2014-01-01

    Background/Objectives Evidence suggests that the child care environment may be more obesogenic than the family home, and previous studies have found that child care use may be associated with obesity in children. Few studies, however, have focused on child care during infancy, which may be an especially vulnerable period. This study examined child care use in infancy and weight status at 12 months of age in a country where paid maternity leave is common and early child care is not as prevalent as in other developed countries. Subjects/Methods We studied 27821 children born to mothers participating in the Danish National Birth Cohort (DNBC), a longitudinal study of pregnant women enrolled between 1997 and 2002, who were also included in the Childcare Database, a national record of child care use in Denmark. The exposure was days in child care from birth to 12 months. The outcomes were sex-specific body mass index (BMI) z-score and overweight/obesity (BMI ≥85th percentile based on the World Health Organization classification) at 12 months. We conducted multivariable linear and logistic regression analyses examining child care use and weight outcomes. Results A total of 17721 (63.7%) children attended child care during their first year of life. After adjustment for potential confounders, a 30-day increment of child care was associated with a modestly higher BMI z-score at 12 months (0.03 units; 95% CI: 0.01, 0.05; p=0.003). Similarly, child care use was associated with increased odds of being overweight/obese at 12 months of age (OR 1.05; 95% CI: 1.01, 1.10; p=0.047). Conclusions Child care in the first year of life was associated with slightly higher weight at 12 months, suggesting that child care settings may be important targets for obesity prevention in infancy. PMID:25233894

  19. Oral health promotion in early childhood: age of joining preventive program and behavioral aspects

    PubMed Central

    Lemos, Letícia Vargas Freire Martins; Myaki, Silvio Issáo; Walter, Luiz Reynaldo de Figueiredo; Zuanon, Angela Cristina Cilense

    2014-01-01

    ABSTRACT Objective: To analyze the interference of age in the entrance into a public dental care program for infants as well as family behavioral aspects about tooth decay experience in children 0 to 4 years old. Methods: Cross-sectional study involving 465 children who were divided into 3 groups: infants whose mothers joined the program during pregnancy (n=50); infants enrolled in the program during the first year of life (n=230); and infants enrolled in the program between 13 and 18 months old (n=185). The χ2 and Kruskal-Walis tests (95% confidence interval) were used to assess the relationship among variables. Results: There was an association between the age of entrance in the programs and dental caries (p<0.001). A lower prevalence was seen in infants whose mothers joined the program during pregnancy, and among those infants enrolled in the program during the first year of life. The same low prevalence occurred in relation to mothers' commitment to attend follow-up visits with their infants, cariogenic diet, nighttime oral care, duration of night feeding and parents' educational level (p<0.001). Unfavorable socioeconomic conditions (p>0.05) and daily oral care (p=0.214) were common variables in the groups with 99% of occurrence. Commitment to attend follow-up visits, nighttime oral care and parents' educational level (p>0.05) were considered protective factors for dental caries. Cariogenic diet and night feeding were determinant factors to the appearance of dental caries. Conclusion: To promote children oral health it is essential to enroll children in oral health programs and adopt healthy habits as early as possible, besides the adherence of the child to their parents' advice. PMID:24728238

  20. The Relationship Between Maillard Reaction Product Formation and the Strength of Griege Yarns Subjected to Accelerated Ageing Conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous work examining the effect of ageing on cotton fiber surface chemical and HVI properties, yarn processing performance, and yarn quality showed that cotton bales stored for extended periods exhibit significant changes in a number of these variables including primarily surface sugar content, H...

  1. Mortality Increase in Late-Middle and Early-Old Age: Heterogeneity in Death Processes as a New Explanation

    PubMed Central

    Yang, Yang Claire; Anderson, James J.

    2014-01-01

    Deviations from the Gompertz law of exponential mortality increases in late-middle and early-old age are commonly neglected in overall mortality analyses. In this study, we examined mortality increase patterns between ages 40 and 85 in 16 low-mortality countries and demonstrated sex differences in these patterns, which also changed across period and cohort. These results suggest that the interaction between aging and death is more complicated than what is usually assumed from the Gompertz law and also challenge existing biodemographic hypotheses about the origin and mechanisms of sex differences in mortality. We propose a two-mortality model that explains these patterns as the change in the composition of intrinsic and extrinsic death rates with age. We show that the age pattern of overall mortality and the population heterogeneity therein are possibly generated by multiple dynamics specified by a two-mortality model instead of a uniform process throughout most adult ages. PMID:23743628

  2. Stressful Events in Early Childhood and Developmental Trajectories of Bedwetting at School Age

    PubMed Central

    Sullivan, Sarah; von Gontard, Alexander; Heron, Jon

    2016-01-01

    Objective To examine whether early stressful events are associated with developmental trajectories of bedwetting. Methods This is a prospective cohort study comprising 8,761 participants from the Avon Longitudinal Study of Parents and Children. Stressful events were measured using a maternal questionnaire completed at 3 time points before their child was 4 years old. The association between stressful events and trajectories of bedwetting from 4 to 9 years was examined using multinomial regression. Results The association with stressful events was strongest for the frequent persistent bedwetting trajectory (wetting at least twice a week up to age 9). A 1 standard deviation increase in the stressful events score was associated with a 29% (13–47%) increase in the odds of experiencing frequent persistent bedwetting compared with normal attainment of nighttime bladder control. Conclusions Clinicians and parents should be aware that continence is a developmental outcome that is associated with high levels of stress in the family. PMID:27072719

  3. Early Aging in Chernobyl Clean-Up Workers: Long-Term Study

    PubMed Central

    Krasnov, V.; Kryukov, V.; Samedova, E.; Emelianova, I.; Ryzhova, I.

    2015-01-01

    This paper represents data of long-term open prospective study. 312 male clean-up workers, who participated in elimination of the Chernobyl disaster consequences in 1986-87, were observed and examined in Moscow Research Institute of Psychiatry. The average age of patients was 57,0 ± 6,8 years. All patients were diagnosed with psychoorganic syndrome, caused by combination of different factors, which led to early cerebrovascular pathology, which was confirmed by clinical, neuropsychological, and instrumental examination. Anamnesis and the level of social adaptation were also assayed. Clinical estimation was done with the use of specially developed Clinical Psychopathological Chart. All the symptoms were divided into 4 groups (asthenic, psychovegetative, dysthymic, and cognitive symptom-complexes). No pronounced signs of dementia were observed. The control group included 44 clean-up workers without mental disorders. Predomination of various exogenous factors before and after accident was noted. Therapy included different vasotropic remedies, as well as family therapy, art therapy, and cognitive training. The possibilities of the reverse development of symptoms were statistically proved. The results allow making a conclusion that these disorders could not be explained either by radiation effects or by PTSD but connected with cerebrovascular pathology. PMID:25692150

  4. Maternal Alcohol Consumption during Pregnancy and Early Age Leukemia Risk in Brazil

    PubMed Central

    Ferreira, Jeniffer Dantas; Couto, Arnaldo Cézar; Pombo-de-Oliveira, Maria S.; Koifman, Sergio

    2015-01-01

    Objectives. To investigate the association between the maternal alcohol consumption during pregnancy and early age leukemia (EAL) in offspring. Methods. Datasets were analyzed from a case-control study carried out in Brazil during 1999–2007. Data were obtained by maternal interviews using a standardized questionnaire. The present study included 675 children (193 acute lymphoid leukemia (ALL), 59 acute myeloid leukemia (AML), and 423 controls). Unconditional logistic regression was performed, and adjusted odds ratios (adj. OR) on the association between alcohol consumption and EAL were ascertained. Results. Alcohol consumption was reported by 43% of ALL and 39% of AML case mothers and 35.5% of controls'. Beer consumption before and during pregnancy was associated with ALL in crude analysis (OR = 1.54, 95% CI, 1.08–2.19), although in adjusted analysis no statistical significance was found. For weekly intake of ≤1 glass (adj. OR = 1.30, 95% CI, 0.71–2.36) and ≥1 glass/week (adj. OR = 1.47, 95% CI, 0.88–2.46) a potential dose-response was observed (P trend < 0.03). Conclusion. This study failed to support the hypothesis of an increased risk of EAL associated with maternal alcohol intake during pregnancy, neither with the interaction with tobacco nor with alcohol consumption. PMID:26090439

  5. Effect of conditioning methods on the microtensile bond strength of phosphate monomer-based cement on zirconia ceramic in dry and aged conditions.

    PubMed

    Amaral, Regina; Ozcan, Mutlu; Valandro, Luiz Felipe; Balducci, Ivan; Bottino, Marco Antonio

    2008-04-01

    The objective of this study was to evaluate the durability of bond strength between a resin cement and aluminous ceramic submitted to various surface conditioning methods. Twenty-four blocks (5 x 5 x 4 mm(3)) of a glass-infiltrated zirconia-alumina ceramic (In-Ceram Zirconia Classic) were randomly divided into three surface treatment groups: ST1-Air-abrasion with 110-mum Al2O3 particles + silanization; ST2-Laboratory tribochemical silica coating method (110-microm Al2O3, 110-microm silica) (Rocatec) + silanization; ST3-Chairside tribochemical silica coating method (30-microm SiO(x)) (CoJet) + silanization. Each treated ceramic block was placed in its silicone mold with the treated surface exposed. The resin cement (Panavia F) was prepared and injected into the mold over the treated surface. Specimens were sectioned to achieve nontrimmed bar specimens (14 sp/block) that were randomly divided into two conditions: (a) Dry-microtensile test after sectioning; (b) Thermocycling (TC)-(6,000x, 5-55 degrees C) and water storage (150 days). Thus, six experimental groups were obtained (n = 50): Gr1-ST1 + dry; Gr2-ST1 + TC(;) Gr3-ST2 + dry; Gr4-ST2 + TC; Gr5-ST3 + dry; Gr6-ST3 + TC. After microtensile testing, the failure types were noted. ST2 (25.1 +/- 11) and ST3 (24.1 +/- 7.4) presented statistically higher bond strength (MPa) than that of ST1 (17.5 +/- 8) regardless of aging conditions (p < 0.0001). While Gr2 revealed the lowest results (13.3 +/- 6.4), the other groups (21.7 +/- 7.4-25. 9 +/- 9.1) showed statistically no significant differences (two-way ANOVA and Tukey's test, alpha = 0.05). The majority of the failures were mixed (82%) followed by adhesive failures (18%). Gr2 presented significantly higher incidence of ADHESIVE failures (54%) than those of other groups (p = 0.0001). Both laboratory and chairside silica coating plus silanization showed durable bond strength. After aging, air-abrasion with 110-microm Al(2)O(3) + silanization showed the largest decrease

  6. Leveraging paraprofessionals and family strengths to improve coverage and penetration of nutrition and early child development services

    PubMed Central

    Tomlinson, Mark; Rahman, Atif; Sanders, David; Maselko, Joanna; Rotheram-Borus, Mary Jane

    2013-01-01

    Children need to be protected in intergenerational networks, with parents who have positive mood, resources to feed their children, and skills to promote early childhood development (ECD). Globally, more than 200 million children are raised annually without these resources. This article reviews the potential contributions of increasing coverage and penetration of services for these children, challenges to achieving penetration of services in high risk families, the opportunities created by bundling multiple services within one provider, the potential leveraging of paraprofessionals to deliver care, and mobilizing communities to support children in households at high risk for negative outcomes. We end with a number of suggestions for how to ensure the equitable scale up of integrated ECD and nutrition services that take into account current global priorities, as well as coverage and penetration of services. PMID:24117669

  7. Language Abilities of Internationally Adopted Children from China during the Early School Years: Evidence for Early Age Effects?

    ERIC Educational Resources Information Center

    Delcenserie, Audrey; Genesee, Fred; Gauthier, Karine

    2013-01-01

    We assessed the language, cognitive, and socioemotional abilities of 27 internationally adopted children from China, adopted by French-speaking parents, 12 of whom had been assessed previously by Gauthier and Genesee. The children were on average 7 years, 10 months old and were matched to nonadopted monolingual French-speaking children on age,…

  8. The Frankfurt early intervention program FFIP for preschool aged children with autism spectrum disorder: a pilot study.

    PubMed

    Freitag, Christine M; Feineis-Matthews, Sabine; Valerian, Jennifer; Teufel, Karoline; Wilker, Christian

    2012-09-01

    Different early intervention programs, developed predominantly in the US, for preschool aged children with autism spectrum disorders (ASD) have been published. Several systematic review articles including a German Health Technology Assessment on behavioural and skill-based early interventions in children with ASD reported insufficient evidence and a substantial problem of generalisability to the German context. In Germany, approx. 2-5 h early intervention is supported by social services. Here, we report the results of a 1 year pre-post pilot study on a developmentally based social pragmatic approach, the Frankfurt Early Intervention program FFIP. In FFIP, individual 2:1, behaviourally and developmentally based therapy with the child is combined with parent training and training of kindergarten teachers. Treatment frequency is 2 h/week. Outcome measures were the Vineland Adaptive Behaviour Scales II (VABS), mental age and the ADOS severity score. Improvements after 1 year were observed for the VABS socialisation scale and the mental age quotient/IQ (medium effect sizes). Results are comparable with several other studies with a similar or slightly higher therapeutic intensity implementing comparable or different early intervention methods or programs. Compared to most high-intensity programs (30-40 h/week), lower cognitive gains were observed. Results have to be replicated and assessed by a randomized-controlled study before any final conclusions can be drawn.

  9. The Subtlety of Age, Gender, and Race Barriers: A Case Study of Early Career African American Female Principals

    ERIC Educational Resources Information Center

    Jean-Marie, Gaetane

    2013-01-01

    While all educational leaders face challenges in achieving success, African American female principals often face a unique set of challenges associated with the complexity of their gender, race, and, as examined in this study, age. This case study investigates the experiences of two highly visible, early career African American female principals…

  10. The Development of Early Literacy Skills among Children with Speech Difficulties: A Test of the "Critical Age Hypothesis".

    ERIC Educational Resources Information Center

    Nathan, Liz; Stackhouse, Joy; Goulandris, Nata; Snowling, Margaret J.

    2004-01-01

    This article presents a longitudinal study of the early literacy development of 47 children with speech difficulties from ages 4 to 7 years. Of these children, 19 with specific speech difficulties were compared with 19 children with speech and language difficulties and 19 normally developing controls. The risk of literacy difficulties was greater…

  11. Digital Natives Come of Age: The Reality of Today's Early Career Teachers Using Mobile Devices to Teach Mathematics

    ERIC Educational Resources Information Center

    Orlando, Joanne; Attard, Catherine

    2016-01-01

    Digital natives are now of age and comprise the new generation of early career teachers (ECTs). This is an important change in teacher demographics given that new technologies have been introduced into classrooms with expectations that teachers embed them effectively into the teaching of mathematics. This paper draws on the data of three separate…

  12. The Quality of Preterm Infants' Spontaneous Movements: An Early Indicator of Intelligence and Behaviour at School Age

    ERIC Educational Resources Information Center

    Butcher, Phillipa R.; van Braeckel, Koen; Bouma, Anke; Einspieler, Christa; Stremmelaar, Elisabeth F.; Bos, Arend F.

    2009-01-01

    Background: The quality of very preterm infants' spontaneous movements at 11 to 16 weeks post-term age is a powerful predictor of their later neurological status. This study investigated whether early spontaneous movements also have predictive value for the intellectual and behavioural problems that children born very preterm often experience.…

  13. Academic Outcomes for School-Aged Children with Severe-Profound Hearing Loss and Early Unilateral and Bilateral Cochlear Implants

    ERIC Educational Resources Information Center

    Sarant, Julia Z.; Harris, David C.; Bennet, Lisa A.

    2015-01-01

    Purpose: This study sought to (a) determine whether academic outcomes for children who received early cochlear implants (CIs) are age appropriate, (b) determine whether bilateral CI use significantly improves academic outcomes, and (c) identify other factors that are predictive of these outcomes. Method: Forty-four 8-year-old children with…

  14. Effectiveness of a School-Based Early Intervention CBT Group Programme for Children with Anxiety Aged 5-7 Years

    ERIC Educational Resources Information Center

    Ruocco, Sylvia; Gordon, Jocelynne; McLean, Louise A.

    2016-01-01

    Early manifestations of anxiety in childhood confer significant distress and life interference. This study reports on the first controlled trial of the "Get Lost Mr. Scary" programme, a Cognitive Behavioural Therapy group intervention for children with anxiety aged 5-7 years. Participants were 134 children (65 males and 69 females) drawn…

  15. GhNAC12, a neutral candidate gene, leads to early aging in cotton (Gossypium hirsutum L).

    PubMed

    Zhao, Fengli; Ma, Jianhui; Li, Libei; Fan, Shuli; Guo, Yaning; Song, Meizhen; Wei, Hengling; Pang, Chaoyou; Yu, Shuxun

    2016-01-15

    NAC (NAM, ATAF, and CUC) is one of the largest transcription factor families in plants, and its members play various roles in plant growth, development, and the response to biotic and abiotic stresses. Currently, 77 NAC genes have been reported in cotton (Gossypium hirsutum L.). And GhNAC12 showed up-regulation during leaf senescence, but its role in this process is poorly understood. In the present study, a preliminary function analysis of GhNAC12 was performed during leaf senescence. qRT-PCR analysis indicated that GhNAC12 expression increased during the early-aging process and the aging of cotyledons. Additionally, we observed that overexpression of GhNAC12 in Arabidopsis led to early senescence (early aging). Our findings suggest that GhNAC12 is a candidate gene for early aging in upland cotton cultivars. Neutrality tests suggested that there was no selection pressure imposed on GhNAC12 during the domestication of upland cotton.

  16. "Math Talk" in Families of Preschool-Aged Children: Frequency and Relations to Children's Early Math Skills across Time

    ERIC Educational Resources Information Center

    Susperreguy Jorquera, Maria Ines

    2013-01-01

    Early math skills are the strongest predictors of later math achievement in school. This two-wave study addressed three research questions about the role of families in fostering these skills in preschool-aged children. First, how do families talk about math at home? Second, how do these conversations vary across families with different…

  17. The Enduring Predictive Significance of Early Maternal Sensitivity: Social and Academic Competence through Age 32 Years

    ERIC Educational Resources Information Center

    Raby, K. Lee; Roisman, Glenn I.; Fraley, R. Chris; Simpson, Jeffry A.

    2015-01-01

    This study leveraged data from the Minnesota Longitudinal Study of Risk and Adaptation (N = 243) to investigate the predictive significance of maternal sensitivity during the first 3 years of life for social and academic competence through age 32 years. Structural model comparisons replicated previous findings that early maternal sensitivity…

  18. Early Adverse Environments and Genetic Influences on Age at First Sex: Evidence for Gene × Environment Interaction

    ERIC Educational Resources Information Center

    Carlson, Marie D.; Mendle, Jane; Harden, K. Paige

    2014-01-01

    Youth who experience adverse environments in early life initiate sexual activity at a younger age, on average, than those from more advantaged circumstances. Evolutionary theorists have posited that ecological stress precipitates earlier reproductive and sexual onset, but it is unclear how stressful environments interact with genetic influences on…

  19. The Age-Crime Curve in Adolescence and Early Adulthood Is Not Due to Age Differences in Economic Status

    ERIC Educational Resources Information Center

    Shulman, Elizabeth P.; Steinberg, Laurence D.; Piquero, Alex R.

    2013-01-01

    One of the most consistent findings in developmental criminology is the "age-crime curve"--the observation that criminal behavior increases in adolescence and decreases in adulthood. Recently, Brown and Males (Justice Policy J 8:1-30, 2011) conducted an analysis of aggregate arrest, poverty, and population data from California and concluded that…

  20. The occurrence of disability and early old-age pensions among members of the carpenters and cabinet makers' trade union.

    PubMed

    Sabroe, S; Olsen, J

    1980-01-01

    The objectives of this study were to estimate the incidence of receiving an early retirement pension among a group of skilled workers and to examine the pattern of the major categories of diagnoses for which pensions were awarded. During the period April 1, 1971 to March 31, 1976, 589 union members were awarded disability pensions and 361 were awarded early old-age pensions. The incidence density of disability pensions is very low among young union members but is observed to increase with age. The Standard Disability Ratio also increases with age, indicating that the age-specific disability pensioning rate increases more rapidly among union members than among the standard population of all men in Denmark. The low rate of pensioning observed among young union members is probably due to healthy worker selection. Low Standard Disability Ratios are found for early old-age pensioners when a standard population of all men in Denmark is used. An examination was made of the diagnoses for which disability pensions were awarded in the two largest occupational sub-groups of the union, cabinet makers and carpenters. Carpenters were found to have high Standard Proportional Ratio for the category "accidents" while cabinet makers have high ratio for the category "diseases of the nervous system".

  1. Effect of Maternal Age on the Ratio of Cleavage and Mitochondrial DNA Copy Number in Early Developmental Stage Bovine Embryos

    PubMed Central

    TAKEO, Shun; GOTO, Hiroya; KUWAYAMA, Takehito; MONJI, Yasunori; IWATA, Hisataka

    2012-01-01

    Abstract Age-associated deterioration in both the quality and quantity of mitochondria occurs in older women. The main aim of this study was to examine the effect of age on mitochondrial DNA copy number (mtDNA number) in early developmental stage bovine embryos as well as the dynamics of mtDNA number during early embryo development. Real-time PCR was used to determine mtDNA number. In vitro-produced embryos 48 h after insemination derived from Japanese black cows, ranging in age from 25 to 209 months were categorized based on their cleavage status. There was an overall negative relationship between the age of the cow and cleavage status, to the extent that the ratio of embryos cleaved over the 4-cell stage was greater in younger cows. The mtDNA number did not differ among the cleaved status of embryos. In the next experiment, oocytes collected from each donor cow were divided into 2 groups containing 10 oocytes each, in order to compare the mtDNA number of mature oocytes and early developmental stage embryos within individuals. Upon comparing the mtDNA number between oocytes at the M2 stage and early developmental stage 48 h post insemination, mtDNA number was found to decrease in most cows, but was found to increase in some cows. In conclusion, age affects the cleaving ability of oocytes, and very old cows (> 180 months) tend to have lower mtDNA numbers in their oocytes. The change in mtDNA number during early development varied among individual cows, although overall, it showed a tendency to decrease. PMID:23269452

  2. Bacillus amyloliquefaciens supplementation alleviates immunological stress in lipopolysaccharide-challenged broilers at early age.

    PubMed

    Li, Y; Zhang, H; Chen, Y P; Yang, M X; Zhang, L L; Lu, Z X; Zhou, Y M; Wang, T

    2015-07-01

    This study was conducted to investigate the effect of Bacillus amyloliquefaciens ( BA: ) on the immune function of broilers challenged with lipopolysaccharide ( LPS: ). 192 one-day-old male Arbor Acre broiler chickens were randomly distributed into four treatments: 1) broilers fed a basal diet; 2) broilers fed a basal diet supplemented with BA; 3) LPS-challenged broilers fed a basal diet; and 4) LPS-challenged broilers fed a basal diet supplemented with BA. Each treatment consisted of six replicates with eight broilers per replicate. Broilers were intraperitoneally injected with either 500 μg LPS per kg body weight or sterile saline at 16, 18 and 20 d of age. LPS decreased the average daily gain ( ADG: , P = 0.001) and average daily feed intake (P = 0.001). The decreased ADG (P = 0.009) and increased feed conversion ratio (P = 0.047) in LPS-challenged broilers were alleviated by BA. LPS increased the relative spleen weight (P = 0.001). Relative spleen (P = 0.014) and bursa (P = 0.024) weights in the LPS-challenged broilers were reduced by BA. LPS increased white blood cell ( WBC: ) numbers (P = 0.001). However, the WBC numbers (P = 0.042) and the ratio of lymphocytes to WBC (P = 0.020) in LPS-challenged broilers were decreased with BA treatment. LPS decreased plasma lysozyme activity (P = 0.001), but increased concentrations of plasma corticosterone (P = 0.012) and IL-2 (P = 0.020). In contrast, BA increased lysozyme activity in plasma (P = 0.040). LPS increased mRNA abundances of splenic toll-like receptor 4 (P = 0.046), interferon γ (P = 0.008), IL-1β (P = 0.045) and IL-6, (P = 0.006). IL-2 (P = 0.014) and IL-6 (P = 0.074) mRNA abundances in LPS-challenged broilers were reduced by BA, although BA had an opposite effect for IL-10 mRNA expression in those broilers (P = 0.004). In conclusion, BA supplementation could partially alleviate the compromised growth performance and immune status of broilers under immune stress induced by LPS challenge at early age. PMID

  3. Micromorphological investigation on ring road sediments of the Early Bronze Age site Tell Chuera, Syria

    NASA Astrophysics Data System (ADS)

    Fritzsch, Dagmar; Thiemeyer, Heinrich

    2010-05-01

    Tell Chuera is an Early Bronze Age settlement mount in NE-Syria close to the Turkish border. With a diameter of almost 1 km and a height of 18 m it is one of the biggest tells in the region between the rivers Balikh and Khabur. In 1958 the structures of the city wall was known first by Orthmann (1990). This city wall was built of air-dried mud bricks. The age of the founding of this construction is not yet clear. The earliest pottery from the place is dated around 2500 BC to 2350 BC. Inside the fortification a road was detected, which was first excavated by Novak (1995). We took sediment monoliths in 2004 from a new trench, which shows the same situation of the road. A geomagnetic prospection, that included the whole site, suggests that the road was part of the planned extension of the lower town and serves as a circular road (Meyer, in prep.). The micromorphological investigation focussed on the question, how the road was used. Did animals have had access to the town? The thin sections show different indications of the anthropogenic influence. In all samples pseudomorphs after straw are visible. In many parts ash, charred wood fragments, bone fragments, melted material and fragments of basalt and flint were observable, too. These materials are typical for sediments in streets (cf. Goldberg & Macphail, 2006). In some parts of the thin sections faecal spherulites and dung remains with faecal spherulites give an idea that ruminants used the road as well as men. Trampling structures support this assumption. Moreover, leaching of calcite, its redeposition in mottles, pseudomycels and concretions, hydromorphic stains and the translocation of silt indicate postdepositional pedogenic processes. Literature Goldberg, P., & Macphail, R. I. (2006). Practical and theoretical geoarchaeology: UK Blackwell Publishing. Meyer, J.-W. (in prep.). Überlegungen zur Siedlungsstruktur - eine erste Analyse der Ergebnisse der geomagnetischen Prospektion. In J.-W. Meyer (Ed.), Ausgrabungen

  4. The Little Six Personality Dimensions From Early Childhood to Early Adulthood: Mean-Level Age and Gender Differences in Parents' Reports.

    PubMed

    Soto, Christopher J

    2016-08-01

    The present research pursues three major goals. First, we develop scales to measure the Little Six youth personality dimensions: Extraversion, Agreeableness, Conscientiousness, Neuroticism, Openness to Experience, and Activity. Second, we examine mean-level age and gender differences in the Little Six from early childhood into early adulthood. Third, we examine the development of more specific nuance traits. We analyze parent reports, made using the common-language California Child Q-Set (CCQ), for a cross-sectional sample of 16,000 target children ranging from 3 to 20 years old. We construct CCQ-Little Six scales that reliably measure each Little Six dimension. Using these scales, we find (a) curvilinear, U-shaped age trends for Agreeableness, Conscientiousness, and Openness, with declines followed by subsequent inclines; (b) monotonic, negative age trends for Extraversion and Activity; (c) higher levels of Conscientiousness and Agreeableness among girls than boys, as well as higher levels of Activity among boys than girls; and (d) gender-specific age trends for Neuroticism, with girls scoring higher than boys by mid-adolescence. Finally, we find that several nuance traits show distinctive developmental trends that differ from their superordinate Little Six dimension. These results highlight childhood and adolescence as key periods of personality development.

  5. Early Shifts of Brain Metabolism by Caloric Restriction Preserve White Matter Integrity and Long-Term Memory in Aging Mice

    PubMed Central

    Guo, Janet; Bakshi, Vikas; Lin, Ai-Ling

    2015-01-01

    Preservation of brain integrity with age is highly associated with lifespan determination. Caloric restriction (CR) has been shown to increase longevity and healthspan in various species; however, its effects on preserving living brain functions in aging remain largely unexplored. In the study, we used multimodal, non-invasive neuroimaging (PET/MRI/MRS) to determine in vivo brain glucose metabolism, energy metabolites, and white matter structural integrity in young and old mice fed with either control or 40% CR diet. In addition, we determined the animals’ memory and learning ability with behavioral assessments. Blood glucose, blood ketone bodies, and body weight were also measured. We found distinct patterns between normal aging and CR aging on brain functions – normal aging showed reductions in brain glucose metabolism, white matter integrity, and long-term memory, resembling human brain aging. CR aging, in contrast, displayed an early shift from glucose to ketone bodies metabolism, which was associated with preservations of brain energy production, white matter integrity, and long-term memory in aging mice. Among all the mice, we found a positive correlation between blood glucose level and body weight, but an inverse association between blood glucose level and lifespan. Our findings suggest that CR could slow down brain aging, in part due to the early shift of energy metabolism caused by lower caloric intake, and we were able to identify the age-dependent effects of CR non-invasively using neuroimaging. These results provide a rationale for CR-induced sustenance of brain health with extended longevity. PMID:26617514

  6. Exposure to omega-3 fatty acids at early age accelerate bone growth and improve bone quality.

    PubMed

    Koren, Netta; Simsa-Maziel, Stav; Shahar, Ron; Schwartz, Betty; Monsonego-Ornan, Efrat

    2014-06-01

    Omega-3 fatty acids (FAs) are essential nutritional components that must be obtained from foods. Increasing evidence validate that omega-3 FAs are beneficial for bone health, and several mechanisms have been suggested to mediate their effects on bone, including alterations in calcium absorption and urinary calcium loss, prostaglandin synthesis, lipid oxidation, osteoblast formation and inhibition of osteoclastogenesis. However, to date, there is scant information regarding the effect of omega-3 FAs on the developing skeleton during the rapid growth phase. In this study we aim to evaluate the effect of exposure to high levels of omega-3 FAs on bone development and quality during prenatal and early postnatal period. For this purpose, we used the fat-1 transgenic mice that have the ability to convert omega-6 to omega-3 fatty acids and the ATDC5 chondrogenic cell line as models. We show that exposure to high concentrations of omega-3 FAs at a young age accelerates bone growth through alterations of the growth plate, associated with increased chondrocyte proliferation and differentiation. We further propose that those effects are mediated by the receptors G-protein coupled receptor 120 (GPR120) and hepatic nuclear factor 4α, which are expressed by chondrocytes in culture. Additionally, using a combined study on the structural and mechanical bone parameters, we show that high omega-3 levels contribute to superior trabecular and cortical structure, as well as to stiffer bones and improved bone quality. Most interestingly, the fat-1 model allowed us to demonstrate the role of maternal high omega-3 concentration on bone growth during the gestation and postnatal period.

  7. Early-age mortality, socio-economic development and the health system in Mongolia.

    PubMed

    Neupert, R F

    1995-04-01

    Since the 1920s Mongolia has developed an extensive and well-staffed health care system that has made modern health technologies accessible to most of its population. In addition, the country experienced rapid economic and social development whose benefits were equitably distributed among the population. In spite of this progress, infant and child mortality levels are high by contemporary standards and during the past 20 years these rates have remained virtually constant. The modern health care delivery system, externally imposed, failed to take into account the specific characteristics of the Mongolian culture; this fact is identified as one of the major determinants of the unexpected levels of early-age mortality. The excessive orientation toward curative medicine, the lack of health prevention and promotion activities and the lack of community participation have resulted in the people continuing to believe in traditional therapeutic patterns and self-care. They perceive the modern system exclusively in curative terms and not with regard to health preservation and disease prevention. Most Mongolians do not fully understand the health care system, and use its services mainly because they have no alternative, or because of coercion rather than conviction based on the learning and internalization of its basic principles. In practices and ideas of child care, preservation of health and disease prevention, people seem to identify more with the traditional health care system. Like other former socialist countries, Mongolia is experiencing deep economic and social transformations, whose implications for the health care system are discussed. An economic crisis whose end is nowhere in sight, emergent social inequalities, a vague health insurance model with unclear financing sources, and lack of concern by most policy-makers in strengthening the preventive component of the health system, are not positive factors for substantial infant and child mortality decline in the

  8. Automatic segmentation of the hippocampus for preterm neonates from early-in-life to term-equivalent age

    PubMed Central

    Guo, Ting; Winterburn, Julie L.; Pipitone, Jon; Duerden, Emma G.; Park, Min Tae M.; Chau, Vann; Poskitt, Kenneth J.; Grunau, Ruth E.; Synnes, Anne; Miller, Steven P.; Mallar Chakravarty, M.

    2015-01-01

    Introduction The hippocampus, a medial temporal lobe structure central to learning and memory, is particularly vulnerable in preterm-born neonates. To date, segmentation of the hippocampus for preterm-born neonates has not yet been performed early-in-life (shortly after birth when clinically stable). The present study focuses on the development and validation of an automatic segmentation protocol that is based on the MAGeT-Brain (Multiple Automatically Generated Templates) algorithm to delineate the hippocampi of preterm neonates on their brain MRIs acquired at not only term-equivalent age but also early-in-life. Methods First, we present a three-step manual segmentation protocol to delineate the hippocampus for preterm neonates and apply this protocol on 22 early-in-life and 22 term images. These manual segmentations are considered the gold standard in assessing the automatic segmentations. MAGeT-Brain, automatic hippocampal segmentation pipeline, requires only a small number of input atlases and reduces the registration and resampling errors by employing an intermediate template library. We assess the segmentation accuracy of MAGeT-Brain in three validation studies, evaluate the hippocampal growth from early-in-life to term-equivalent age, and study the effect of preterm birth on the hippocampal volume. The first experiment thoroughly validates MAGeT-Brain segmentation in three sets of 10-fold Monte Carlo cross-validation (MCCV) analyses with 187 different groups of input atlases and templates. The second experiment segments the neonatal hippocampi on 168 early-in-life and 154 term images and evaluates the hippocampal growth rate of 125 infants from early-in-life to term-equivalent age. The third experiment analyzes the effect of gestational age (GA) at birth on the average hippocampal volume at early-in-life and term-equivalent age using linear regression. Results The final segmentations demonstrate that MAGeT-Brain consistently provides accurate segmentations

  9. Early age-related changes in episodic memory retrieval as revealed by event-related potentials.

    PubMed

    Guillaume, Cécile; Clochon, Patrice; Denise, Pierre; Rauchs, Géraldine; Guillery-Girard, Bérengère; Eustache, Francis; Desgranges, Béatrice

    2009-01-28

    Familiarity is better preserved than recollection in ageing. The age at which changes first occur and the slope of the subsequent decline, however, remain unclear. In this study, we investigated changes in episodic memory, by using event-related potentials (ERPs) in young (m=24), middle-aged (m=58) and older (m=70) adults. Although behavioural performance did not change before the age of 65 years, changes in ERP correlates were already present in the middle-aged adults. The ERP correlates of recollection and monitoring processes were the first to be affected by ageing, with a linear decrease as age increased. Conversely, the ERP correlate of familiarity remained unchanged, at least up to the age of 65 years. These results suggest a differential time course for the age effects on episodic retrieval. PMID:19104457

  10. Early-Onset Convulsive Seizures Induced by Brain Hypoxia-Ischemia in Aging Mice: Effects of Anticonvulsive Treatments

    PubMed Central

    Peng, Jessie; Patel, Nisarg; Huang, Yayi; Gao, Xiaoxing; Aljarallah, Salman; Eubanks, James H.; McDonald, Robert; Zhang, Liang

    2015-01-01

    Aging is associated with an increased risk of seizures/epilepsy. Stroke (ischemic or hemorrhagic) and cardiac arrest related brain injury are two major causative factors for seizure development in this patient population. With either etiology, seizures are a poor prognostic factor. In spite of this, the underlying pathophysiology of seizure development is not well understood. In addition, a standardized treatment regimen with anticonvulsants and outcome assessments following treatment has yet to be established for these post-ischemic seizures. Previous studies have modeled post-ischemic seizures in adult rodents, but similar studies in aging/aged animals, a group that mirrors a higher risk elderly population, remain sparse. Our study therefore aimed to investigate early-onset seizures in aging animals using a hypoxia-ischemia (HI) model. Male C57 black mice 18-20-month-old underwent a unilateral occlusion of the common carotid artery followed by a systemic hypoxic episode (8% O2 for 30 min). Early-onset seizures were detected using combined behavioral and electroencephalographic (EEG) monitoring. Brain injury was assessed histologically at different times post HI. Convulsive seizures were observed in 65% of aging mice post-HI but not in control aging mice following either sham surgery or hypoxia alone. These seizures typically occurred within hours of HI and behaviorally consisted of jumping, fast running, barrel-rolling, and/or falling (loss of the righting reflex) with limb spasms. No evident discharges during any convulsive seizures were seen on cortical-hippocampal EEG recordings. Seizure development was closely associated with acute mortality and severe brain injury on brain histological analysis. Intra-peritoneal injections of lorazepam and fosphenytoin suppressed seizures and improved survival but only when applied prior to seizure onset and not after. These findings together suggest that seizures are a major contributing factor to acute mortality in aging

  11. Early-type galaxy archeology: Ages, abundance ratios, and effective temperatures from full-spectrum fitting

    SciTech Connect

    Conroy, Charlie; Graves, Genevieve J.; Van Dokkum, Pieter G.

    2014-01-01

    The stellar populations of galaxies hold vital clues to their formation histories. In this paper we present results based on modeling stacked spectra of early-type galaxies drawn from the Sloan Digital Sky Survey as a function of velocity dispersion, σ, from 90 km s{sup –1} to 300 km s{sup –1}. The spectra are of extremely high quality, with typical signal-to-noise ratio of 1000 Å{sup –1}, and a wavelength coverage of 4000 Å –8800 Å. Our population synthesis model includes variation in 16 elements from C to Ba, a two-component star formation history, the shift in effective temperature, Δ T {sub eff}, of the stars with respect to a solar metallicity isochrone, and the stellar initial mass function, among other parameters. In our approach we fit the full optical spectra rather than a select number of spectral indices and are able to, for the first time, measure the abundances of the elements V, Cr, Mn, Co, and Ni from the integrated light of distant galaxies. Our main results are as follows: (1) light-weighted stellar ages range from 6-12 Gyr from low to high σ; (2) [Fe/H] varies by less than 0.1 dex across the entire sample; (3) Mg closely tracks O, and both increase from ≈0.0 at low σ to ∼0.25 at high σ; Si and Ti show a shallower rise with σ, and Ca tracks Fe rather than O; (4) the iron peak elements V, Cr, Mn, and Ni track Fe, while Co tracks O, suggesting that Co forms primarily in massive stars; (5) C and N track O over the full sample and [C/Fe] and [N/Fe] exceed 0.2 at high σ; and (6) the variation in Δ T {sub eff} with total metallicity closely follows theoretical predictions based on stellar evolution theory. This last result is significant because it implies that we are robustly solving not only for the detailed abundance patterns but also the detailed temperature distributions (i.e., isochrones) of the stars in these galaxies. A variety of tests reveal that the systematic uncertainties in our measurements are probably 0.05 dex or

  12. Early Age of First Sex and Health Risk in an Urban Adolescent Population

    ERIC Educational Resources Information Center

    Kaplan, Deborah L.; Jones, Elizabeth J.; Olson, E. Carolyn; Yunzal-Butler, Cristina B.

    2013-01-01

    Background: Early sex is associated with high-risk behaviors and outcomes, including sexual risk behaviors, forced sex, physical dating violence, and becoming pregnant or impregnating someone. Methods: Using 2005 and 2007 data from the New York City Youth Risk Behavior Survey (N = 17,220), this study examined the prevalence of early sex among…

  13. Tangible Steps Toward Tomorrow: New Designs for Early Education, Ages 0-8

    ERIC Educational Resources Information Center

    W. K. Kellogg Foundation, 2007

    2007-01-01

    This publication, developed by W.K. Kellogg Foundation in collaboration with IDEO, details a human-centered approach to evolving the system of early education for the needs and possibilities of the 21st century. It provides a set of ideas or "thought-starters" on transforming early education to ensure school readiness and success for the next…

  14. Emotional Development among Early School-Age Children: Gender Differences in the Role of Problem Behaviours

    ERIC Educational Resources Information Center

    Maguire, Lisa K.; Niens, Ulrike; McCann, Mark; Connolly, Paul

    2016-01-01

    There has been an increasing focus on social and emotional development in educational programmes in early childhood as both variables are believed to influence behavioural outcomes in the classroom. However, relationships between social and emotional development and behaviour in early childhood have rarely been explored. This article sets out to…

  15. Age at Adoption from Institutional Care as a Window into the Lasting Effects of Early Experiences

    ERIC Educational Resources Information Center

    Julian, Megan M.

    2013-01-01

    One of the major questions of human development is how early experience impacts the course of development years later. Children adopted from institutional care experience varying levels of deprivation in their early life followed by qualitatively better care in an adoptive home, providing a unique opportunity to study the lasting effects of early…

  16. Developmentally Appropriate Practice in Early Childhood Programs Serving Children from Birth through Age 8. Third Edition

    ERIC Educational Resources Information Center

    Copple, Carol, Ed.; Bredekamp, Sue, Ed.

    2009-01-01

    Since the first edition in 1987, National Association for the Education of Young Children's book "Developmentally Appropriate Practice in Early Childhood Programs" has been an essential resource for the early child care field. Now fully revised and expanded, the 2009 version comes with a supplementary CD containing readings on key topics, plus…

  17. Improved Stress Corrosion Cracking Resistance and Strength of a Two-Step Aged Al-Zn-Mg-Cu Alloy Using Taguchi Method

    NASA Astrophysics Data System (ADS)

    Lin, Lianghua; Liu, Zhiyi; Ying, Puyou; Liu, Meng

    2015-12-01

    Multi-step heat treatment effectively enhances the stress corrosion cracking (SCC) resistance but usually degrades the mechanical properties of Al-Zn-Mg-Cu alloys. With the aim to enhance SCC resistance as well as strength of Al-Zn-Mg-Cu alloys, we have optimized the process parameters during two-step aging of Al-6.1Zn-2.8Mg-1.9Cu alloy by Taguchi's L9 orthogonal array. In this work, analysis of variance (ANOVA) was performed to find out the significant heat treatment parameters. The slow strain rate testing combined with scanning electron microscope and transmission electron microscope was employed to study the SCC behaviors of Al-Zn-Mg-Cu alloy. Results showed that the contour map produced by ANOVA offered a reliable reference for selection of optimum heat treatment parameters. By using this method, a desired combination of mechanical performances and SCC resistance was obtained.

  18. Ages of tuff beds at East African early hominid sites and sediments in the Gulf of Aden

    USGS Publications Warehouse

    Sarna-Wojcicki, A. M.; Meyer, C.E.; Roth, P.H.; Brown, F.H.

    1985-01-01

    The early hominids of East Africa were dated by determining the ages of tuff beds at the sites. Despite much research using palaeomagnetic and K/Ar-dating techniques, some of those ages are still controversial 1,2. To obtain independent age estimates for these tephra layers, we have examined cores from DSDP Sites 231 and 232 in the Gulf of Aden (Fig. 1a) which consist mainly of calcareous nannofossil ooze, but also contain rare tephra horizons3 dated by interpolation from the established nannofossil stratigraphy (Fig. 1b). Chemical analysis confirms that the identity and sequence of these horizons is the same as that at the East African sites. We conclude that the age of the Tulu Bor Tuff is <3.4 Myr and hence that the Hadar hominid specimens are also

  19. Historical reconstruction of storms in the West of France in the early Little Ice Age.

    NASA Astrophysics Data System (ADS)

    Athimon, Emmanuelle; Maanan, Mohamed

    2016-04-01

    This research offers to : 1) identify, as accurately as possible, the storms and the coastal flooding in the early Little Ice Age, 2) expose their impacts on the environment and populations, 3) query the « resilience » and adaptation of medieval and modern coastal societies in the West of France by presenting their perceptions and reactions. The space-time frame of the study is located in France, from Brittany to Gascony, between the xivth and the xvith century. Sensitive and brittle, this area is regularly battered by violent winds. It also undergoes episodic sea flooding that can cause ruptures of balance. Hence, the historical reconstruction and analysis of storms and coastal flooding in a long period appear fundamental. A thorough knowledge of past meteo-marine hazards allows to recreate a link with the territory, particularly through the (re)construction of an effective memory of these phenomena. This process is essential however difficult because of many documentary gaps. They are due to historical contingencies such as wars, French Revolution, or archival disasters like the fire of the Chamber of Accounts in Paris in 1737. Many limits must also be taken into account and discussed as inaccurate dates, exaggerated or undervalued descriptions, strict spatial demarcation almost impossible to achieve for the xivth-xvith centuries. Furthermore, during this period, no death toll, material and economic balance was done after a climate disaster. Yet, many historical records - especially narrative sources, books of accounts or cities repairs - expose the impacts of storms and marine submersion on agriculture, environment, infrastructures, etc. For instance, a violent storm hit the coast on June 24th 1452. It washed away part of the roof of a castle on Noirmoutier island and knocked down the bell towers of two churches in Angers. Storms and sea flooding have affected activities, constructions and populations' lives. They have therefore forced societies to adapt

  20. Are early onset aging conditions correlated to daily activity functions in youth and adults with Down syndrome?

    PubMed

    Lin, Jin-Ding; Lin, Lan-Ping; Hsu, Shang-Wei; Chen, Wen-Xiu; Lin, Fu-Gong; Wu, Jia-Ling; Chu, Cordia

    2014-11-13

    This study aims to answer the research question of "Are early onset aging conditions correlated to daily activity functions in youth and adults with Down syndrome (DS)?" A cross-sectional survey was employed to recruit 216 individuals with DS over 15 years of age in the analyses. A structured questionnaire included demographic data, brief self-reported aging conditions, Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID) and activity of daily living (ADL) scales were completed by the primary caregivers who were well-suited for providing information on the functioning conditions of the DS individuals. Results showed that the most five frequent aging conditions (sometimes, usually and always) included frailty (20.2%), vision problem (15.8%), loss of language ability (15.3%), sleep problem (14.9%) and memory impairment (14.5%). Other onset aging conditions included more chronic diseases (13.9%), hearing loss (13%), chewing ability and tooth loss (12.5%), incontinence (11.1%), depressive syndrome (7.7%), falls and gait disorder (7.2%), loss of taste and smell (7.2%). The data also showed scores of DSQIID, onset aging conditions and ADL has significant relationships each other in Pearson's correlation tests. Finally, multiple linear regression analyses indicated onset aging conditions (β=-0.735, p<0.001) can significantly predicted the variation in ADL scores after adjusting other factors (R(2)=0.381). This study suggests that the authority should initiate early intervention programs aim to improve healthy aging and ADL functions for people with DS. PMID:25462513

  1. Temporal variations in the strength of the Antarctic coastal current from the provenance and comminution ages of Weddell Sea sediments

    NASA Astrophysics Data System (ADS)

    Torfstein, A.; McManus, J. F.

    2012-12-01

    The location and geometric setting of the Weddell Sea, one of the large marginal seas of Antarctica, make it a sensitive recorder of the input of subglacial erosion products from Antarctica. We present evidence for variability in the sources and temporal fluxes of Antarctic continental erosion products, based on Pb, Sr and Nd isotopic compositions, U-decay series and trace element concnetrations of sediments deposited over the last ~250 kyrs in the East and deep-North Weddell Sea, at sites PS1388 and PS1170, respectively. Each sediment sample was separated into three grain size fractions of authigenic-free material (>20um, 20-2um, <2um). Significant differences are observed in sediment composition from the two studied regions as well as between grain size fractions within each sample. Lead isotopic compositions show a clear distinction between both sites with 206Pb/204Pb ratios at sites PS1388 and PS1170 ranging between 17.958-18.307 and 18.655-18.939, repsectively. The isotopic composition of Sr is generally similar at both sites, in the range of 0.715-0.723, except for <2um particles from PS1170 that display significantly higher values in the range of 0.726-0.734. The latter also display the strongest 234U-depletion with typical (234U/238U) ratios around 0.8. These observations imply that the clay size fraction in the North Weddell Sea originates from a distant region, most likely East Antarctica, and that it was exposed to more intense weathering and transport processes relative to the coarser particles. Hence, secular variations in 87Sr/86Sr and (234U/238U) ratios provide a sensitive recorder of the the sediments comminution ages (i.e., their time of transport between source and sink) and the intensity of weathering processes they were exposed to. The combined evidence supports enhanced rates of sediment transport by the Antarctic coastal current from the East Antarctic sector to the Weddell Sea during interglacial stages compared to glacial times, with

  2. [Peloid therapy in the complex sanatorium treatment of children of early age with complications of perinatal brain damage].

    PubMed

    Ponomareva, S O; Babina, L M

    2003-01-01

    The search for novel approaches to multimodality prophylaxis and treatment of sequelae of perinatal nervous system affection as well as introduction of the early diagnostic criteria are topical problems in present-day pediatric neurology. Peloid therapy efficacy in combined sanatorium treatment was studied (Peloterm unit) in 44 infants aged 1 to 3 years. They suffered from sequelae of perinatal affections of the central nervous system including infantile cerebral paralysis. A positive effect (improvement of motor and psychic-speech development) was achieved in 98% cases. This indicates validity of this method in the treatment of CNS affections following perinatal affection of the brain in infants over 1 year of age. PMID:14753007

  3. Orchidectomy-induced alterations in volumetric bone density, cortical porosity and strength of femur are attenuated by dietary conjugated linoleic acid in aged guinea pigs.

    PubMed

    DeGuire, Jason R; Mak, Ivy L; Lavery, Paula; Agellon, Sherry; Wykes, Linda J; Weiler, Hope A

    2015-04-01

    Age-related osteoporosis and sarcopenia are ascribed in part to reductions in anabolic hormones. Dietary conjugated linoleic acid (CLA) improves lean and bone mass, but its impact during androgen deficiency is not known. This study tested if CLA would attenuate the effects of orchidectomy (ORX)-induced losses of bone and lean tissue. Male guinea pigs (n=40; 70-72 weeks), were randomized into four groups: (1) SHAM+Control diet, (2) SHAM+CLA diet, (3) ORX+Control diet, (4) ORX+CLA diet. Baseline blood sampling and dual-energy X-ray absorptiometry (DXA) scans were conducted, followed by surgery 4 days later with the test diets started 7 days after baseline sampling. Serial blood sampling and DXA scans were repeated 2, 4, 8 and 16 weeks on the test diets. Body composition and areal BMD (aBMD) of whole body, lumbar spine, femur and tibia were measured using DXA. At week 16, muscle protein fractional synthesis rate (FSR), volumetric BMD (vBMD), microarchitecture and bone strength were assessed. Body weight declined after SHAM and ORX surgery, with slower recovery in the ORX group. Dietary CLA did not affect weight or lean mass, but attenuated gains in fat mass. Lean mass was stable in SHAM and reduced in ORX by 2 weeks with whole body and femur bone mineral content (BMC) reduced by 4 weeks; CLA did not alter BMC. By week 16 ORX groups had lower free testosterone and myofibrillar FSR, yet higher cortisol, osteocalcin and ionized calcium with no alterations due to CLA. ORX+Control had higher prostaglandin E2 (PGE2) and total alkaline phosphatase compared to SHAM+Control whereas ORX+CLA were not different from SHAM groups. Femur metaphyseal vBMD was reduced in ORX+CTRL with the reduction attenuated by CLA. Femur cortical thickness (Ct.Th.) and biomechanical strength were reduced and cortical porosity (Ct.Po.) elevated by ORX and attenuated by CLA. This androgen deficient model with a sarcopenic-osteoporotic phenotype similar to aging men responded to dietary CLA with

  4. Toward generic principles of treating parents and children: integrating psychotherapy with the school-aged child and early family intervention.

    PubMed

    Heinicke, C M

    1990-12-01

    Generic principles governing the outcome and process of the treatment of children and their families can be generated from both research on the psychotherapy of school-aged children and early family intervention. Evidence indicates that the amenability of the child or parent to treatment and the comprehensiveness, duration, and intensity of the helping process are significant parameters. Definition of significant early family intervention roles allows linkage to various therapeutic roles with school-aged children and forces the recognition that most treatment situations involve more roles than are officially recognized. This articulation of the profile of intervention roles among poverty level, first-time parents at risk for neglecting their infant drew on several bodies of theory: psychoanalytic, cognitive, behavioral, social cognitive, and positive reinforcement principles, and advocacy and direct assistance as used in clinical social casework.

  5. Nebraska Early Learning Guidelines for Ages Birth to 3: Nurturing the Development and Learning of Infants and Toddlers through Responsive Caregiving

    ERIC Educational Resources Information Center

    Nebraska Department of Education, 2006

    2006-01-01

    This resource provides information to assist parents, family members, early childhood teachers, caregivers, and other adults in promoting the learning and development of young children ages birth to three. It is a companion to the Nebraska Early Learning Guidelines for Ages 3 to 5, and uses the same format and domains of development. This…

  6. Does the early frog catch the worm? Disentangling potential drivers of a parasite age-intensity relationship in tadpoles.

    PubMed

    Raffel, Thomas R; Lloyd-Smith, James O; Sessions, Stanley K; Hudson, Peter J; Rohr, Jason R

    2011-04-01

    The manner in which parasite intensity and aggregation varies with host age can provide insights into parasite dynamics and help identify potential means of controlling infections in humans and wildlife. A significant challenge is to distinguish among competing mechanistic hypotheses for the relationship between age and parasite intensity or aggregation. Because different mechanisms can generate similar relationships, testing among competing hypotheses can be difficult, particularly in wildlife hosts, and often requires a combination of experimental and model fitting approaches. We used field data, experiments, and model fitting to distinguish among ten plausible drivers of a curvilinear age-intensity relationship and increasing aggregation with host age for echinostome trematode infections of green frogs. We found little support for most of these proposed drivers but did find that the parsimonious explanation for the observed age-intensity relationship was seasonal exposure to echinostomes. The parsimonious explanation for the aggregated distribution of parasites in this host population was heterogeneity in exposure. A predictive model incorporating seasonal exposure indicated that tadpoles hatching early or late in the breeding season should have lower trematode burdens at metamorphosis, particularly with simulated warmer climates. Application of this multi-pronged approach (field surveys, lab experiments, and modeling) to additional parasite-host systems could lead to discovery of general patterns in the drivers of parasite age-intensity and age-distribution relationships.

  7. Aging Stereotypes Must be Taken Into Account for the Diagnosis of Prodromal and Early Alzheimer Disease.

    PubMed

    Régner, Isabelle; Mazerolle, Marie; Alescio-Lautier, Béatrice; Clarys, David; Michel, Bernard; Paccalin, Marc; Piolino, Pascale; Rigalleau, François; Sambuchi, Nathalie; Huguet, Pascal

    2016-01-01

    Because of a dramatic increase of older people worldwide, screening for prodromal state of Alzheimer disease (AD) is a major societal challenge. Many individuals diagnosed with prodromal AD, do not convert to AD, some remaining stable and others reversing back to normal. We argue that an important source of this overdiagnosis comes from negative aging stereotypes (eg, the culturally shared beliefs that aging inescapably causes severe cognitive decline and diseases). Many laboratory studies show that such stereotypes impair memory performance in healthy older adults, producing inflated age differences. Research is needed to examine how aging stereotypes implicitly permeate neuropsychological testing and contribute to false positives.

  8. The enduring predictive significance of early maternal sensitivity: social and academic competence through age 32 years.

    PubMed

    Raby, K Lee; Roisman, Glenn I; Fraley, R Chris; Simpson, Jeffry A

    2015-01-01

    This study leveraged data from the Minnesota Longitudinal Study of Risk and Adaptation (N = 243) to investigate the predictive significance of maternal sensitivity during the first 3 years of life for social and academic competence through age 32 years. Structural model comparisons replicated previous findings that early maternal sensitivity predicts social skills and academic achievement through midadolescence in a manner consistent with an enduring effects model of development and extended these findings using heterotypic indicators of social competence (effectiveness of romantic engagement) and academic competence (educational attainment) during adulthood. Although early socioeconomic factors and child gender accounted for the predictive significance of maternal sensitivity for social competence, covariates did not fully account for associations between early sensitivity and academic outcomes.

  9. Examination of age-related epigenetic changes following early-life exposure to dichloroacetic acid

    EPA Science Inventory

    Recent studies have shown that transient early-life exposure to dichloroacetic acid (DCA), a pyruvate analog and metabolic reprogramming agent, increases liver cancer incidence in older mice. This carcinogenic effect is not associated with direct mutagenicity, persistent cytotoxi...

  10. White Matter Integrity and Reaction Time Intraindividual Variability in Healthy Aging and Early-Stage Alzheimer Disease

    PubMed Central

    Jackson, Jonathan D.; Balota, David A.; Duchek, Janet M.; Head, Denise

    2011-01-01

    Aging and early-stage Alzheimer disease (AD) have been shown to be associated with increased RT intraindividual variability (IIV, as reflected by the coefficient of variation) and an exaggeration of the slow tail of the RT distribution in attentional control tasks, based on ex-Gaussian analyses. The current study examined associations between white matter volume, IIV, and ex-Gaussian RT distribution parameters in cognitively normal aging and early-stage AD. Three RT attention tasks (Stroop, Simon, and a consonant-vowel odd-even switching task) in conjunction with MRI-based measures of cerebral and regional white matter volume were obtained in 133 cognitively normal and 33 early-stage AD individuals. Larger volumes were associated with less IIV and less slowing in the tail of the RT distribution, and larger cerebral and inferior parietal white matter volumes were associated with faster modal reaction time. Collectively, these results support a role of white matter integrity in IIV and distributional skewing, and are consistent with the hypothesis that IIV and RT distributional skewing are sensitive to breakdowns in executive control processes in normal and pathological aging. PMID:22172547

  11. Early Child L2 Acquisition: Age or Input Effects? Neither, or Both?

    ERIC Educational Resources Information Center

    Unsworth, Sharon

    2016-01-01

    This paper explores whether there is evidence for age and/or input effects in child L2 acquisition across three different linguistic domains, namely morphosyntax, vocabulary, and syntax-semantics. More specifically, it compares data from English-speaking children whose age of onset to L2 Dutch was between one and three years with data from…

  12. UNDERNUTRITION IN EARLY LIFE DOES NOT IMPAIR LEARNING IN YOUNG OR AGING RATS.

    EPA Science Inventory

    Prenatal undernutrition is associated with increased incidence of obesity, heart disease, diabetes. Effects of pre- and post-natal undernutrition on nervous system function in middle-aged and aging male SD rats were examined. Intrauterine growth retardation (IUGR) was induced by ...

  13. EXAMINING LONG-TERM EFFECTS OF AN INFANT MENTAL HEALTH HOME-BASED EARLY HEAD START PROGRAM ON FAMILY STRENGTHS AND RESILIENCE.

    PubMed

    Mckelvey, Lorraine; Schiffman, Rachel F; Brophy-Herb, Holly E; Bocknek, Erika London; Fitzgerald, Hiram E; Reischl, Thomas M; Hawver, Shelley; Cunningham Deluca, Mary

    2015-01-01

    Infant Mental Health based interventions aim to promote the healthy development of infants and toddlers through promoting healthy family functioning to foster supportive relationships between the young child and his or her important caregivers. This study examined impacts of an Infant Mental Health home-based Early Head Start (IMH-HB EHS) program on family functioning. The sample includes 152 low-income families in the Midwestern United States, expectant or parenting a child younger than 1 year of age, who were randomly assigned to receive IMH-HB EHS services (n = 75) or to a comparison condition (n = 77). Mothers who received IMH-HB EHS services reported healthier psychological and family functioning, outcomes that are consistent with the IMH focus, when their children were between the ages of 3 and 7 years of age. Specifically, mothers in the IMH-HB EHS group reported healthier family functioning and relationships, better coping skills needed to advocate for their families, and less stress in the parenting role versus those in the comparison condition. The study also examined support seeking coping, some of which changed differently over time based on program group assignment. Overall, findings suggest that the gains families achieve from participating in IMH-HB EHS services are maintained after services cease. PMID:26118949

  14. EXAMINING LONG-TERM EFFECTS OF AN INFANT MENTAL HEALTH HOME-BASED EARLY HEAD START PROGRAM ON FAMILY STRENGTHS AND RESILIENCE.

    PubMed

    Mckelvey, Lorraine; Schiffman, Rachel F; Brophy-Herb, Holly E; Bocknek, Erika London; Fitzgerald, Hiram E; Reischl, Thomas M; Hawver, Shelley; Cunningham Deluca, Mary

    2015-01-01

    Infant Mental Health based interventions aim to promote the healthy development of infants and toddlers through promoting healthy family functioning to foster supportive relationships between the young child and his or her important caregivers. This study examined impacts of an Infant Mental Health home-based Early Head Start (IMH-HB EHS) program on family functioning. The sample includes 152 low-income families in the Midwestern United States, expectant or parenting a child younger than 1 year of age, who were randomly assigned to receive IMH-HB EHS services (n = 75) or to a comparison condition (n = 77). Mothers who received IMH-HB EHS services reported healthier psychological and family functioning, outcomes that are consistent with the IMH focus, when their children were between the ages of 3 and 7 years of age. Specifically, mothers in the IMH-HB EHS group reported healthier family functioning and relationships, better coping skills needed to advocate for their families, and less stress in the parenting role versus those in the comparison condition. The study also examined support seeking coping, some of which changed differently over time based on program group assignment. Overall, findings suggest that the gains families achieve from participating in IMH-HB EHS services are maintained after services cease.

  15. Age effects on the social interaction test in early adulthood male rats.

    PubMed

    Garau, A; Martí, M A; Sala, J; Balada, F

    2000-01-01

    The effects of age on active and passive social interaction were studied in Wistar rats using the social interaction test (S.I.T.). Individual behaviors such as ambulation, rearing, and defecation were also studied. Despite the widespread use of the S.I.T. in anxiety research, the effects of age on the S.I.T. have not been studied thoroughly. Male Wistar rats of 75, 135, and 180 days old were used. Our results showed age effects on active social contact, passive social contact, ambulation, rearing, and defecation. At 135 days old, animals presented the lowest scores on active social behavior and the highest scores on defecation. Moreover, exploratory behavior measured by ambulation and rearing decreased with age. These results suggest that age could be a relevant variable in the social interaction test.

  16. p47phox-Nox2-dependent ROS Signaling Inhibits Early Bone Development in Mice but Protects against Skeletal Aging*

    PubMed Central

    Chen, Jin-Ran; Lazarenko, Oxana P.; Blackburn, Michael L.; Mercer, Kelly E.; Badger, Thomas M.; Ronis, Martin J. J.

    2015-01-01

    Bone remodeling is age-dependently regulated and changes dramatically during the course of development. Progressive accumulation of reactive oxygen species (ROS) has been suspected to be the leading cause of many inflammatory and degenerative diseases, as well as an important factor underlying many effects of aging. In contrast, how reduced ROS signaling regulates inflammation and remodeling in bone remains unknown. Here, we utilized a p47phox knock-out mouse model, in which an essential cytosolic co-activator of Nox2 is lost, to characterize bone metabolism at 6 weeks and 2 years of age. Compared with their age-matched wild type controls, loss of Nox2 function in p47phox−/− mice resulted in age-related switch of bone mass and strength. Differences in bone mass were associated with increased bone formation in 6-week-old p47phox−/− mice but decreased in 2-year-old p47phox−/− mice. Despite decreases in ROS generation in bone marrow cells and p47phox-Nox2 signaling in osteoblastic cells, 2-year-old p47phox−/− mice showed increased senescence-associated secretory phenotype in bone compared with their wild type controls. These in vivo findings were mechanistically recapitulated in ex vivo cell culture of primary fetal calvarial cells from p47phox−/− mice. These cells showed accelerated cell senescence pathway accompanied by increased inflammation. These data indicate that the observed age-related switch of bone mass in p47phox-deficient mice occurs through an increased inflammatory milieu in bone and that p47phox-Nox2-dependent physiological ROS signaling suppresses inflammation in aging. PMID:25922068

  17. Self-healing of early age cracks in cement-based materials by mineralization of carbonic anhydrase microorganism

    PubMed Central

    Qian, Chunxiang; Chen, Huaicheng; Ren, Lifu; Luo, Mian

    2015-01-01

    This research investigated the self-healing potential of early age cracks in cement-based materials incorporating the bacteria which can produce carbonic anhydrase. Cement-based materials specimens were pre-cracked at the age of 7, 14, 28, 60 days to study the repair ability influenced by cracking time, the width of cracks were between 0.1 and 1.0 mm to study the healing rate influenced by width of cracks. The experimental results indicated that the bacteria showed excellent repairing ability to small cracks formed at early age of 7 days, cracks below 0.4 mm was almost completely closed. The repair effect reduced with the increasing of cracking age. Cracks width influenced self-healing effectiveness significantly. The transportation of CO2and Ca2+ controlled the self-healing process. The computer simulation analyses revealed the self-healing process and mechanism of microbiologically precipitation induced by bacteria and the depth of precipitated CaCO3 could be predicted base on valid Ca2+. PMID:26583014

  18. Early to Middle Miocene cooling ages on Kea and Kythnos: timing constraints on crustal extension in the western Cyclades

    NASA Astrophysics Data System (ADS)

    Schneider, D. A.; Stockli, D.; Grasemann, B.; Iglseder, Ch.; Rice, A. H. N.; Heizler, M.

    2009-04-01

    The Cyclades are known for their extensional tectonics and recently recognized as having significant bivergence with top-to-NNE and top-to-SSW kinematics. Crustal extension and exhumation of the Attic-Cycladic massif, and in some instances metamorphic core complex formation are the result of back arc extension in the wake of Hellenic subduction retreat. Of the western islands, Kea and Kythnos have remained relatively little investigated even given their critical juncture between mainland Attica and the other Cyclades. Mapping by Team ACCEL indicates the islands are dominated by highly-strained middle greenschist facies Chl-Ep schists, calc-silicates and marbles, folded into open structural domes. Characterizing the tectonostratigraphy is a dominant, meter to decameter thick layer of ultramylonitic marble which is preserved in klippen scattered along the edges of the domes. The most recent brittle deformation is recorded as a number of low-angle normal faults which truncate the domal structure; both these brittle and other ductile (e.g. boudinage) kinematics indicate a consistent SW-directed stretching direction. No unequivocal hanging wall rocks have been identified and neither dome contains evidence of Alpine or younger magmatism. Ar-Ar thermochronometry performed on white mica from various lithologies at different structural levels on Kea yield consistent Early to Middle Miocene (21 Ma to 13 Ma) cooling ages. (U-Th)/He apatite cooling ages are between 14 Ma and 7.5 Ma. Although poorly defined, the older cooling ages are in the middle of the dome and along the geomorphic 'spine' which defines the dome's long axis. White mica from Kythnos yield poor age spectra with integrated ages between 22 Ma and 17 Ma, likely indicating mixed mineral populations were analyzed. The (U-Th)/He apatite cooling ages from this dome are all consistently Middle Miocene, with no evident spatial pattern. We interpret the Early to Middle Miocene cooling ages of the Kea and Kythnos

  19. The strength of sexual arousal as a function of the age of the sex offender: comparisons among pedophiles, hebephiles, and teleiophiles.

    PubMed

    Blanchard, Ray; Barbaree, Howard E

    2005-10-01

    Previous research has shown that sexual arousability in human males declines from its peak in early adolescence until old age. This study compared the rates of decline in three groups of males: those most attracted sexually to prepubescent children (pedophiles), those most attracted to pubescent children (hebephiles), and those most attracted to physically mature persons (teleiophiles). The participants were 2,028 patients referred to Toronto's Centre for Addiction and Mental Health from 1995 to 2004 for evaluation of criminal or otherwise disturbing sexual behavior, but not for erectile or ejaculatory problems. All underwent phallometric assessment for erotic age-preference. This is a psychophysiological technique in which an individual's penile blood volume is monitored while he is presented with a standardized set of laboratory stimuli depicting male and female children, pubescents, and adults. The experimental measure of sexual arousability was the average of the participant's three greatest penile responses to any stimulus category, expressed in cubic cm of blood volume increase. The results showed that sexual arousability was an inverse function of age, and that there were no differences between the pedophiles, hebephiles, and teleiophiles in the rate at which arousability declined. PMID:16341604

  20. Age and date for early arrival of the Acheulian in Europe (Barranc de la Boella, la Canonja, Spain).

    PubMed

    Vallverdú, Josep; Saladié, Palmira; Rosas, Antonio; Huguet, Rosa; Cáceres, Isabel; Mosquera, Marina; Garcia-Tabernero, Antonio; Estalrrich, Almudena; Lozano-Fernández, Iván; Pineda-Alcalá, Antonio; Carrancho, Ángel; Villalaín, Juan José; Bourlès, Didier; Braucher, Régis; Lebatard, Anne; Vilalta, Jaume; Esteban-Nadal, Montserrat; Bennàsar, Maria Lluc; Bastir, Marcus; López-Polín, Lucía; Ollé, Andreu; Vergés, Josep Maria; Ros-Montoya, Sergio; Martínez-Navarro, Bienvenido; García, Ana; Martinell, Jordi; Expósito, Isabel; Burjachs, Francesc; Agustí, Jordi; Carbonell, Eudald

    2014-01-01

    The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ∼1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place.

  1. Age and Date for Early Arrival of the Acheulian in Europe (Barranc de la Boella, la Canonja, Spain)

    PubMed Central

    Vallverdú, Josep; Saladié, Palmira; Rosas, Antonio; Huguet, Rosa; Cáceres, Isabel; Mosquera, Marina; Garcia-Tabernero, Antonio; Estalrrich, Almudena; Lozano-Fernández, Iván; Pineda-Alcalá, Antonio; Carrancho, Ángel; Villalaín, Juan José; Bourlès, Didier; Braucher, Régis; Lebatard, Anne; Vilalta, Jaume; Esteban-Nadal, Montserrat; Bennàsar, Maria Lluc; Bastir, Marcus; López-Polín, Lucía; Ollé, Andreu; Vergés, Josep Maria; Ros-Montoya, Sergio; Martínez-Navarro, Bienvenido; García, Ana; Martinell, Jordi; Expósito, Isabel; Burjachs, Francesc; Agustí, Jordi; Carbonell, Eudald

    2014-01-01

    The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ∼1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place. PMID:25076416

  2. Age-related cortical thickness trajectories in first episode psychosis patients presenting with early persistent negative symptoms

    PubMed Central

    Makowski, Carolina; Bodnar, Michael; Malla, Ashok K; Joober, Ridha; Lepage, Martin

    2016-01-01

    Recent work has clearly established that early persistent negative symptoms (ePNS) can be observed following a first episode of psychosis (FEP), and can negatively affect functional outcome. There is also evidence for cortical changes associated with ePNS. Given that a FEP often occurs during a period of ongoing complex brain development and maturation, neuroanatomical changes may have a specific age-related component. The current study examines cortical thickness (CT) and trajectories with age using longitudinal structural imaging. Structural T1 volumes were acquired at three time points for ePNS (N=21), PNS due to secondary factors (N=31), non-PNS (N=45) patients, and controls (N=48). Images were processed using the CIVET pipeline. Linear mixed models were applied to test for the main effects of (a) group, (b) time, and interactions between (c) time and group membership, and (d) age and group membership. Compared with the non-PNS and secondary PNS patient groups, the ePNS group showed cortical thinning over time in temporal regions and a thickening with age primarily in prefrontal areas. Early PNS patients also had significantly different linear and quadratic age relationships with CT compared with other groups within cingulate, prefrontal, and temporal cortices. The current study demonstrates that FEP patients with ePNS show significantly different CT trajectories with age. Increased CT may be indicative of disruptions in cortical maturation processes within higher-order brain regions. Individuals with ePNS underline a unique subgroup of FEP patients that are differentiated at the clinical level and who exhibit distinct neurobiological patterns compared with their non-PNS peers. PMID:27602388

  3. Age-related cortical thickness trajectories in first episode psychosis patients presenting with early persistent negative symptoms

    PubMed Central

    Makowski, Carolina; Bodnar, Michael; Malla, Ashok K; Joober, Ridha; Lepage, Martin

    2016-01-01

    Recent work has clearly established that early persistent negative symptoms (ePNS) can be observed following a first episode of psychosis (FEP), and can negatively affect functional outcome. There is also evidence for cortical changes associated with ePNS. Given that a FEP often occurs during a period of ongoing complex brain development and maturation, neuroanatomical changes may have a specific age-related component. The current study examines cortical thickness (CT) and trajectories with age using longitudinal structural imaging. Structural T1 volumes were acquired at three time points for ePNS (N=21), PNS due to secondary factors (N=31), non-PNS (N=45) patients, and controls (N=48). Images were processed using the CIVET pipeline. Linear mixed models were applied to test for the main effects of (a) group, (b) time, and interactions between (c) time and group membership, and (d) age and group membership. Compared with the non-PNS and secondary PNS patient groups, the ePNS group showed cortical thinning over time in temporal regions and a thickening with age primarily in prefrontal areas. Early PNS patients also had significantly different linear and quadratic age relationships with CT compared with other groups within cingulate, prefrontal, and temporal cortices. The current study demonstrates that FEP patients with ePNS show significantly different CT trajectories with age. Increased CT may be indicative of disruptions in cortical maturation processes within higher-order brain regions. Individuals with ePNS underline a unique subgroup of FEP patients that are differentiated at the clinical level and who exhibit distinct neurobiological patterns compared with their non-PNS peers.

  4. Age-related cortical thickness trajectories in first episode psychosis patients presenting with early persistent negative symptoms.

    PubMed

    Makowski, Carolina; Bodnar, Michael; Malla, Ashok K; Joober, Ridha; Lepage, Martin

    2016-01-01

    Recent work has clearly established that early persistent negative symptoms (ePNS) can be observed following a first episode of psychosis (FEP), and can negatively affect functional outcome. There is also evidence for cortical changes associated with ePNS. Given that a FEP often occurs during a period of ongoing complex brain development and maturation, neuroanatomical changes may have a specific age-related component. The current study examines cortical thickness (CT) and trajectories with age using longitudinal structural imaging. Structural T1 volumes were acquired at three time points for ePNS (N=21), PNS due to secondary factors (N=31), non-PNS (N=45) patients, and controls (N=48). Images were processed using the CIVET pipeline. Linear mixed models were applied to test for the main effects of (a) group, (b) time, and interactions between (c) time and group membership, and (d) age and group membership. Compared with the non-PNS and secondary PNS patient groups, the ePNS group showed cortical thinning over time in temporal regions and a thickening with age primarily in prefrontal areas. Early PNS patients also had significantly different linear and quadratic age relationships with CT compared with other groups within cingulate, prefrontal, and temporal cortices. The current study demonstrates that FEP patients with ePNS show significantly different CT trajectories with age. Increased CT may be indicative of disruptions in cortical maturation processes within higher-order brain regions. Individuals with ePNS underline a unique subgroup of FEP patients that are differentiated at the clinical level and who exhibit distinct neurobiological patterns compared with their non-PNS peers. PMID:27602388

  5. Longitudinal association between early life socio-environmental factors and attention function at the age 11 years.

    PubMed

    Forns, Joan; Torrent, Maties; Garcia-Esteban, Raquel; Cáceres, Alejandro; Pilar Gomila, María; Martinez, David; Morales, Eva; Julvez, Jordi; Grimalt, Joan O; Sunyer, Jordi

    2012-08-01

    Prenatal and early-life exposures can affect the course of children's neuropsychological development well into pre-adolescence, given the vulnerability of the developing brain. However, it is unknown which socio-environmental factors at early childhood can influence specific cognitive processes like attention at a later age. In this study, we aim to determine social and environmental exposures in early childhood that may be associated with attention function of 11-year-olds. We measured attention function using the continuous performance test-II (CPT-II) on 393 11-year old children from the Menorca's birth-cohort within the INMA-project (Spain), and pre-selected a list of socio-environmental observations taken when they were up to 4 years of age. We found that earlier socio-environmental characteristics, such as parental social class, educational level and maternal mental health are associated with later inattentive and impulsive symptomatology through a higher rate of omission and commission errors. In addition, omission errors were higher in children with atopy and lower in those whose mothers took dietary supplementation with folic acid and vitamins during pregnancy. Breastfeeding played a protective role against commission errors, while higher DDE and PCBs levels at age 4 were associated with slow speed response. Our findings suggest that a number of life socio-environmental factors during prenatal life and early childhood, such as socio-demographic characteristics, breastfeeding, maternal nutritional supplementation with folic acid and vitamins and exposure to some organochlorine compounds may influence inattentive and hyperactive/impulsive symptomatology during pre-adolescence. PMID:22608140

  6. Longitudinal association between early life socio-environmental factors and attention function at the age 11 years.

    PubMed

    Forns, Joan; Torrent, Maties; Garcia-Esteban, Raquel; Cáceres, Alejandro; Pilar Gomila, María; Martinez, David; Morales, Eva; Julvez, Jordi; Grimalt, Joan O; Sunyer, Jordi

    2012-08-01

    Prenatal and early-life exposures can affect the course of children's neuropsychological development well into pre-adolescence, given the vulnerability of the developing brain. However, it is unknown which socio-environmental factors at early childhood can influence specific cognitive processes like attention at a later age. In this study, we aim to determine social and environmental exposures in early childhood that may be associated with attention function of 11-year-olds. We measured attention function using the continuous performance test-II (CPT-II) on 393 11-year old children from the Menorca's birth-cohort within the INMA-project (Spain), and pre-selected a list of socio-environmental observations taken when they were up to 4 years of age. We found that earlier socio-environmental characteristics, such as parental social class, educational level and maternal mental health are associated with later inattentive and impulsive symptomatology through a higher rate of omission and commission errors. In addition, omission errors were higher in children with atopy and lower in those whose mothers took dietary supplementation with folic acid and vitamins during pregnancy. Breastfeeding played a protective role against commission errors, while higher DDE and PCBs levels at age 4 were associated with slow speed response. Our findings suggest that a number of life socio-environmental factors during prenatal life and early childhood, such as socio-demographic characteristics, breastfeeding, maternal nutritional supplementation with folic acid and vitamins and exposure to some organochlorine compounds may influence inattentive and hyperactive/impulsive symptomatology during pre-adolescence.

  7. Early Tertiary Age of Pitchstone in the Northern Black Hills, South Dakota

    NASA Astrophysics Data System (ADS)

    Redden, Jack A.; Obradovich, John D.; Naeser, Charles W.; Zartman, Robert E.; Norton, James J.

    1983-06-01

    A block of pitchstone in the northern Black Hills, South Dakota, is Paleocene in age, according to potassium-argon dating of biotite and fission-track dating of zircon in the sample. These data invalidate published suggestions that the age is much younger. The pitchstone is not extrusive in its present position but instead is in a volcanic pipe with other fragments that came downward from as much as 1100 meters above the modern surface.

  8. New U-Pb and Rb-Sr ages from northwest Turkey; Early Cretaceous continental collision in the western Pontides

    NASA Astrophysics Data System (ADS)

    Akbayram, K.; Okay, A.; Satır, M.; Topuz, G.

    2009-04-01

    Keywords: Intra-Pontide suture, Ä°stanbul Zone, Sakarya Zone, U-Pb zircon ages, Rb-Sr mica ages We provide new isotopic data from the Intra-Pontide Suture Zone, which indicate Early Cretaceous collision between the Sakarya and Ä°stanbul terranes following the consumption of the Intra-Pontide Ocean. The study area is located south of Sapanca Lake between the Ä°stanbul and Sakarya terranes in northwest Turkey. These two terranes show different geological histories, as reflected in their stratigraphic record, and are juxtaposed along the Intra-Pontide suture. The new U/Pb zircon and Rb/Sr mica ages come from south of the Sapanca Lake, south of the North Anatolian Fault in northwest Turkey. The Ä°stanbul terrane has a late Proterozoic basement (Chen et al., 2002; 570 Ma) overlain by a sedimentary sequence of Ordovician to Carboniferous age. The Sakarya terrane is characterized by Carboniferous (330-310 Ma) high temperature metamorphism (Okay et al., 2006), Paleozoic granitic plutonism (Topuz et al., 2007) and by the presence of Palaeo-Tethyan subduction-accretion units. South of the Sapanca Lake, three main tectonostratigraphic units have been differentiated forming a northeastward dipping thrust stack. At the top of the thrust stack is an amphibolite-facies metamorphic unit consisting of an intercalation of amphibolite, metaperidotite, metapyroxenite and gneiss representing a Proterozoic metaophiolite in the basement of the Istanbul Zone. This old metaophiolite is underlain by a Cretaceous accretionary complex of metabasite, metachert, slate and serpentinite. The lowermost tectonic unit in the thrust stack is a metasandstone, slate, phyllite and marble unit metamorphosed in greenschist facies. Our U/Pb geochronological data comes from the basement gneisses and the metasedimentary unit. The age of deposition and metamorphism of this metasedimentary unit were not constrained. The U/Pb ages of the clastic zircons from metasandstones are between 500-317 Ma. These

  9. AMTA Monograph Series - Effective Clinical Practice in Music Therapy Early Childhood and School Age Educational Settings

    ERIC Educational Resources Information Center

    Humpal, Marcia Earl, Ed.; Colwell, Cynthia, Ed.

    2006-01-01

    Educators, families, and media in increasing numbers are recognizing the unique role music plays in young children's development. More and more daycare, preschool, and early intervention centers offer employment opportunities that reflect the needs and attitudes of our ever-changing society. Furthermore, Federal and state regulations, a changing…

  10. Motor Development in Early Childhood: A Guide for Movement Education with Ages 2 to 6.

    ERIC Educational Resources Information Center

    Flinchum, Betty M.

    This book deals with the following areas: (a) basic motor development and readiness of the young child for movement activities, (b) learning and developmental theories commonly used in early childhood education, (c) instructional approaches for using movement as a learning modality, and (d) general educational implications which can be ascertained…

  11. Effect of the Responsive Environment Early Education Program for Low Birth Weight Children of Preschool Age.

    ERIC Educational Resources Information Center

    Askins, Billy E.; And Others

    This paper describes an external evaluation study of the Responsive Environment Early Education Program (formerly known as the Responsive Environment Program for Spanish American Children), an educational intervention program for "high risk" (low birth weight) 3-, 4-, and 5-year-old children in Clovis, New Mexico. Major goals of the program are:…

  12. Korean Diaspora in the Age of Globalization: Early Study Abroad (ESA) College Students in the Midwest

    ERIC Educational Resources Information Center

    Choi, Hee Young

    2012-01-01

    This study examines the unique experiences of international Korean college students in the Midwest who have gone through the early study abroad (ESA) period in the US during their formative secondary school education and the influence of the experiences into their college lives in the mega campus. Two overarching research questions are: 1) how do…

  13. The Stability of General Intelligence from Early Adulthood to Middle-Age

    ERIC Educational Resources Information Center

    Larsen, Lars; Hartmann, Peter; Nyborg, Helmuth

    2008-01-01

    Early cross-sectional studies suggested that cognitive functions begin to decline in young adulthood, whereas the first longitudinal studies suggested that they are mainly stable in adulthood. A number of more contemporary longitudinal studies support the stability hypothesis. However, drop out effects have the consequence that most longitudinal…

  14. Early Language Stimulation of Down's Syndrome Babies: A Study on the Optimum Age To Begin.

    ERIC Educational Resources Information Center

    Aparicio, Maria Teresa Sanz; Balana, Javier Menendez

    2002-01-01

    Examined the marked delay in language acquisition suffered by babies with Down Syndrome and how early treatment affects the subsequent observed development among 36 subjects in Spain. Found statistically significant differences in language acquisitions in favor of newborns, compared with 90-day-old through 18-month-old infants who experienced…

  15. Early Childbearing, Marital Status, and Women's Health and Mortality after Age 50

    ERIC Educational Resources Information Center

    Henretta, John C.

    2007-01-01

    This article examines the relationship between a woman's childbearing history and her later health and mortality, with primary focus on whether the association between them is due to early and later socioeconomic status. Data are drawn from the Health and Retirement Study birth cohort of 1931-1941. Results indicate that, conditional on reaching…

  16. Factors Associated with Early Risk for School-Aged Children Living in Rural Poverty.

    ERIC Educational Resources Information Center

    De Haan, Laura; Gunvalson, Diane

    Early onset of at-risk behaviors has been recognized as an important predictor of severity of negative outcomes during adolescence, but little is known about rural children's involvement in such behaviors and related variables. In two rural Midwest counties with high concentrations of child poverty, a survey of 162 predominantly Caucasian fifth-…

  17. Early and School-Age Care in Santa Monica: Current System, Policy Options, and Recommendations

    ERIC Educational Resources Information Center

    Pierson, Ashley; Karoly, Lynn A.; Zellman, Gail L.; Beckett, Megan K.

    2014-01-01

    The landscape of early learning and out-of-school-time programs in the City of Santa Monica is complex, with numerous providers and funding streams. This complexity reflects its evolution in response to changes in federal, state, and local priorities and initiatives. Future shifts in funding levels, program auspices, and other features are likely.…

  18. Early Childhood Household Smoke Exposure Predicts Less Task-Oriented Classroom Behavior at Age 10

    ERIC Educational Resources Information Center

    Pagani, Linda S.; Fitzpatrick, Caroline

    2016-01-01

    Secondhand tobacco smoke is considered a developmental neurotoxicant especially given underdeveloped vital systems in young children. An ecological test of its negative influence on brain development can be made by examining the prospective association between early childhood household smoke exposure and later classroom behavior. Using a…

  19. Family Connections: Promoting Early Literacy Skills--Ages Birth to 5

    ERIC Educational Resources Information Center

    Huisman, Sarah

    2012-01-01

    Reading, writing, and communicating, also known as literacy, are important cognitive skills to teach within society. Early literacy is knowledge about reading and writing before actually being able to read and write and is the foundation to future reading and writing skills (Ghoting & Martin-Diaz, 2006). The role of families in developing early…

  20. Introduction: Cortical event-related potentials and early language development: Variations with age and nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is increasing evidence in the form of language-relevant sensory processing and discrimination that the foundations for speech perception are present at birth and are subject to significant modification during the first year of life. However, charting the course of early language development is...

  1. Qualities for Early Childhood Care and Education in an Age of Increasing Superdiversity and Decreasing Biodiversity

    ERIC Educational Resources Information Center

    Ritchie, Jenny

    2016-01-01

    In this article it is argued that notions of "quality" in early childhood education have been captured by neo-liberal discourses. These discourses perpetuate the western, individualistic, normativising and exploitative attitudes and practices that are contributing to the climate crisis currently imperilling our planet. Educators may…

  2. Early British Printing Meets the Electronic Age: A Large-Scale Digitization Case Study.

    ERIC Educational Resources Information Center

    McLean, Austin J.

    2001-01-01

    Describes the development of production requirements and technical specifications for a microfilm-to-digital conversion project that digitized early English books printed between 1475-1700. Discusses the Internet interface used for access; MARC records; indexing; partnerships with libraries and universities; scanning; database design; and quality…

  3. Effect of prenatal and postnatal malnutrition on intellectual functioning in early school-aged children in rural western China.

    PubMed

    Li, Chao; Zhu, Ni; Zeng, Lingxia; Dang, Shaonong; Zhou, Jing; Yan, Hong

    2016-08-01

    The aim of this study was to evaluate the effect of prenatal and postnatal malnutrition on the intellectual functioning of early school-aged children. We followed the offspring of women who had participated in a trial of prenatal supplementation with different combinations of micronutrients and who remained resident in the study field. We measured their intellectual functioning using the Wechsler intelligence scale for children (WISC-IV). Height-for-age, weight-for-age, and body mass index (BMI)-for-age were used as anthropometric nutritional status indices. Four of the 5 composite scores derived from the WISC-IV, except for working memory index (WMI), were significantly lower in low birth weight children after adjusting for confounds. All 5 composite scores, including full-scale intelligence quotient (FSIQ), verbal comprehension index (VCI), WMI, perceptual reasoning index (PRI), and processing speed index (PSI) were significant lower in stunted and underweight children. The differences in the means of WISC-IV test scores were greatest between stunted and nonstunted children. The means for FSIQ, VCI, WMI, PRI, and PSI were as follows: 5.88 (95% confidence interval [CI]: 2.84-8.92), 5.08 (95% CI: 1.12-8.41), 4.71 (95% CI: 1.78-7.66), 6.13 (95% CI: 2.83-9.44), and 5.81 (95% CI: 2.61-9.00). These means were lower in stunted children after adjusting for confounds. Our results suggest the important influences of low birth weight and postnatal malnutrition (stunting, low body weight) on intellectual functioning in early school-aged children. PMID:27495020

  4. Effect of prenatal and postnatal malnutrition on intellectual functioning in early school-aged children in rural western China

    PubMed Central

    Li, Chao; Zhu, Ni; Zeng, Lingxia; Dang, Shaonong; Zhou, Jing; Yan, Hong

    2016-01-01

    Abstract The aim of this study was to evaluate the effect of prenatal and postnatal malnutrition on the intellectual functioning of early school-aged children. We followed the offspring of women who had participated in a trial of prenatal supplementation with different combinations of micronutrients and who remained resident in the study field. We measured their intellectual functioning using the Wechsler intelligence scale for children (WISC-IV). Height-for-age, weight-for-age, and body mass index (BMI)-for-age were used as anthropometric nutritional status indices. Four of the 5 composite scores derived from the WISC-IV, except for working memory index (WMI), were significantly lower in low birth weight children after adjusting for confounds. All 5 composite scores, including full-scale intelligence quotient (FSIQ), verbal comprehension index (VCI), WMI, perceptual reasoning index (PRI), and processing speed index (PSI) were significant lower in stunted and underweight children. The differences in the means of WISC-IV test scores were greatest between stunted and nonstunted children. The means for FSIQ, VCI, WMI, PRI, and PSI were as follows: 5.88 (95% confidence interval [CI]: 2.84–8.92), 5.08 (95% CI: 1.12–8.41), 4.71 (95% CI: 1.78–7.66), 6.13 (95% CI: 2.83–9.44), and 5.81 (95% CI: 2.61–9.00). These means were lower in stunted children after adjusting for confounds. Our results suggest the important influences of low birth weight and postnatal malnutrition (stunting, low body weight) on intellectual functioning in early school-aged children. PMID:27495020

  5. Up, not down: The age curve in happiness from early adulthood to midlife in two longitudinal studies.

    PubMed

    Galambos, Nancy L; Fang, Shichen; Krahn, Harvey J; Johnson, Matthew D; Lachman, Margie E

    2015-11-01

    Happiness is an important indicator of well-being, and little is known about how it changes in the early adult years. We examined trajectories of happiness from early adulthood to midlife in 2 Canadian longitudinal samples: high school seniors followed from ages 18-43 and university seniors followed from ages 23-37. Happiness increased into the 30s in both samples, with a slight downturn by age 43 in the high school sample. The rise in happiness after high school and university remained after controlling for important baseline covariates (gender, parents' education, grades, self-esteem), time-varying covariates known to be associated with happiness (marital status, unemployment, self-rated physical health), and number of waves of participation. The upward trend in happiness runs counter to some previous cross-sectional research claiming a high point in happiness in the late teens, decreasing into midlife. As cross-sectional designs do not assess within-person change, longitudinal studies are necessary for drawing accurate conclusions about patterns of change in happiness across the life span.

  6. Interest of active posturography to detect age-related and early Parkinson's disease-related impairments in mediolateral postural control.

    PubMed

    Bonnet, Cédrick T; Delval, Arnaud; Defebvre, Luc

    2014-11-15

    Patients with Parkinson's disease display impairments of postural control most particularly in active, challenging conditions. The objective of the present study was to analyze early signs of disease-related and also age-related impairments in mediolateral body extension and postural control. Fifty-five participants (18 Hoehn and Yahr stage 2 patients in the off-drug condition, 18 healthy elderly control subjects, and 19 young adults) were included in the study. The participants performed a quiet stance task and two active tasks that analyzed the performance in mediolateral body motion: a limit of stability and a rhythmic weight shift task. As expected, the patients displayed significantly lower and slower body displacement (head, neck, lower back, center of pressure) than elderly control subjects when performing the two body excursion tasks. However, the behavioral variability in both tasks was similar between the groups. Under these active conditions, the patients showed significantly lower contribution of the hip postural control mechanisms compared with the elderly control subjects. Overall, the patients seemed to lower their performance in order to prevent a mediolateral postural instability. However, these patients, at an early stage of their disease, were not unstable in quiet stance. Complementarily, elderly control subjects displayed slower body performance than young adults, which therefore showed an additional age-related impairment in mediolateral postural control. Overall, the study illustrated markers of age-related and Parkinson's disease impairments in mediolateral postural control that may constrain everyday activities in elderly adults and even more in patients with Parkinson's disease.

  7. EVIDENCE FOR INTERMEDIATE-AGE STELLAR POPULATIONS IN EARLY-TYPE GALAXIES FROM K-BAND SPECTROSCOPY

    SciTech Connect

    Marmol-Queralto, E.; Cardiel, N.; Gorgas, J.; Sanchez-Blazquez, P.; Cenarro, A. J.; Vazdekis, A.; Kuntschner, H.; Silva, D. R.

    2009-11-10

    The study of stellar populations in early-type galaxies in different environments is a powerful tool for constraining their star formation histories. This study has been traditionally restricted to the optical range, where dwarfs around the turn-off and stars at the base of the red giant branch dominate the integrated light at all ages. The near-infrared spectral range is especially interesting since in the presence of an intermediate-age population, asymptotic giant branch stars are the main contributors. In this Letter, we measure the near-infrared indices Na I and D {sub CO} for a sample of 12 early-type galaxies in low-density environments and compare them with the Fornax galaxy sample presented by Silva et al.. The analysis of these indices in combination with Lick/IDS indices in the optical range reveals that (1) the Na I index is a metallicity indicator as good as C4668 in the optical range, and (2) D {sub CO} is a tracer of intermediate-age stellar populations. We find that low-mass galaxies in low-density environments show higher Na I and D {sub CO} than those located in the Fornax cluster, which points toward a late stage of star formation for the galaxies in less dense environments, in agreement with results from other studies using independent methods.

  8. Up, not down: The age curve in happiness from early adulthood to midlife in two longitudinal studies.

    PubMed

    Galambos, Nancy L; Fang, Shichen; Krahn, Harvey J; Johnson, Matthew D; Lachman, Margie E

    2015-11-01

    Happiness is an important indicator of well-being, and little is known about how it changes in the early adult years. We examined trajectories of happiness from early adulthood to midlife in 2 Canadian longitudinal samples: high school seniors followed from ages 18-43 and university seniors followed from ages 23-37. Happiness increased into the 30s in both samples, with a slight downturn by age 43 in the high school sample. The rise in happiness after high school and university remained after controlling for important baseline covariates (gender, parents' education, grades, self-esteem), time-varying covariates known to be associated with happiness (marital status, unemployment, self-rated physical health), and number of waves of participation. The upward trend in happiness runs counter to some previous cross-sectional research claiming a high point in happiness in the late teens, decreasing into midlife. As cross-sectional designs do not assess within-person change, longitudinal studies are necessary for drawing accurate conclusions about patterns of change in happiness across the life span. PMID:26347986

  9. Musicians' Enhanced Neural Differentiation of Speech Sounds Arises Early in Life: Developmental Evidence from Ages 3 to 30

    PubMed Central

    Strait, Dana L.; O'Connell, Samantha; Parbery-Clark, Alexandra; Kraus, Nina

    2014-01-01

    The perception and neural representation of acoustically similar speech sounds underlie language development. Music training hones the perception of minute acoustic differences that distinguish sounds; this training may generalize to speech processing given that adult musicians have enhanced neural differentiation of similar speech syllables compared with nonmusicians. Here, we asked whether this neural advantage in musicians is present early in life by assessing musically trained and untrained children as young as age 3. We assessed auditory brainstem responses to the speech syllables /ba/ and /ga/ as well as auditory and visual cognitive abilities in musicians and nonmusicians across 3 developmental time-points: preschoolers, school-aged children, and adults. Cross-phase analyses objectively measured the degree to which subcortical responses differed to these speech syllables in musicians and nonmusicians for each age group. Results reveal that musicians exhibit enhanced neural differentiation of stop consonants early in life and with as little as a few years of training. Furthermore, the extent of subcortical stop consonant distinction correlates with auditory-specific cognitive abilities (i.e., auditory working memory and attention). Results are interpreted according to a corticofugal framework for auditory learning in which subcortical processing enhancements are engendered by strengthened cognitive control over auditory function in musicians. PMID:23599166

  10. New U/Pb ages from Nanpanjiang Basin (South China): implications for the age and definition of the Early-Middle Triassic boundary

    NASA Astrophysics Data System (ADS)

    Ovtcharova, Maria; Bucher, Hugo; Goudemand, Nicolas; Schaltegger, Urs; Brayard, Armand; Galfetti, Thomas

    2010-05-01

    Understanding the patterns and rates of the biotic recovery following the end-Permian extinction requires detailed calibration of both biotic and environmental fluctuations by precise and accurate U-Pb age determinations on zircon from volcanic ash beds within biostratigraphically well dated marine sedimentary sections. Recent analytical developments in U-Pb dating include chemical abrasion pre-treatment of zircon as well as the use of the well calibrated 202Pb-205Pb-233U-235U EARTHTIME tracer solution, leading to <0.1% analytical uncertainties and external reproducibilities. Utilizing these analytical techniques we report new data from the Jinya area in the Nanpanjiang Basin (South China) and compare them to radioisotopic and biochronologic data from Guandao in the same basin (Lehrmann et al. 2006, 2007) The so-called "green-bean rock" (GBR) is an interval rich in volcanic ash beds which is customarily used as a mapping unit to separate Lower from Middle Triassic marine rocks in the Nanpanjiang Basin (Lehrmann et al. 2006). In Guandao, the first occurrence (FO) of the conodont Chiosella timorensis is used to define the base of the middle Triassic. The position of this FO in Guandao is somewhat unstable and underwent a downward shift of 2.6 m between the two consecutive reports of Lehrmann et al. (2006, 2007). The new position of the FO, still bracketed by the same ash layers PGD2 and PGD3 led to a minor readjustment of its linearly interpolated age to 247.24 Ma (Lehrmann et al. 2007). In the basinal Luolou Fm., the GBR amounts to a ca. 3m thick series of composite, laterally transported ashes as indicated by internal sedimentary structures. Ammonoids bracketing the GBR in the Luolou Fm. invariably indicate a late Early Triassic age (Haugi Zone of the Spathian substage). A 13 m thick section straddling the transition between the Luolou Fm. and the overlying Baifeng Fm. was sampled along a new road cut at Monggan (3 km NNW of Jinya). In this section, the 3 m thick

  11. Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations

    USGS Publications Warehouse

    Hudson, Mark R.; John, David A.; Conrad, James E.; McKee, Edwin H.

    2000-01-01

    Paleomagnetic and geochronologic data combined with geologic mapping tightly restrict the timing and character of a late Oligocene to early Miocene episode of large magnitude extension in the southern Stillwater Range and adjacent regions of west central Nevada. The southern Stillwater Range was the site of an Oligocene to early Miocene volcanic center comprising (1) 28.3 to 24.3 Ma intracaldera ash flow tuffs, lava flows, and subjacent plutons associated with three calderas, (2) 24.8 to 20.7 Ma postcaldera silicic dikes and domes, and (3) unconformably overlying 15.3 to 13.0 Ma dacite to basalt lava flows, plugs, and dikes. The caldera-related tuffs, lava flows, and plutons were tilted 60°-70° either west or east during the initial period of Cenozoic deformation that accommodated over 100% extension. Directions of remanent magnetization obtained from these extrusive and intrusive, caldera-related rocks are strongly deflected from an expected Miocene direction in senses appropriate for their tilt. A mean direction for these rocks after tilt correction, however, suggests that they were also affected by a moderate (33.4° ± 11.8°) component of counterclockwise vertical axis rotation. Paleomagnetic data indicate that the episode of large tilting occurred during emplacement of 24.8 to 20.7 Ma postcaldera dikes and domes. In detail, an apparent decrease in rotation with decreasing age of individual, isotopically dated bodies of the postcaldera group indicates that most tilting occurred between 24.4 and 24.2 Ma. The onset of tilting immediately following after the final caldera eruptions suggests that the magmatism and deformation were linked. Deformation was not driven by magma buoyancy, however, because tilting equally affected the caldera systems of different ages, including their plutonic roots. It is more likely that regional extension was focused in the southern Stillwater Range due to magmatic warming and reduction of tensile strength of the brittle crust

  12. Emotional development among early school-age children: gender differences in the role of problem behaviours

    PubMed Central

    Maguire, Lisa K.; Niens, Ulrike; McCann, Mark; Connolly, Paul

    2016-01-01

    There has been an increasing focus on social and emotional development in educational programmes in early childhood as both variables are believed to influence behavioural outcomes in the classroom. However, relationships between social and emotional development and behaviour in early childhood have rarely been explored. This article sets out to investigate the conceptualisation of these variables and their interrelationships. Structural equation models were used to assess whether differences exist between boys and girls in relation to social and emotional competences, which could affect the relative success of such programmes. This article is based on cross-sectional data collected from 749 four- to six-year-olds and their teachers. The findings generally supported the hypothesised relationships between social and emotional development variables and prosocial behaviour (including internalising behaviour) for boys and girls. However, some gender differences were noted in externalising behaviour, which teachers often consider to be most significant due to its potentially disruptive nature in the classroom. PMID:27570322

  13. Early and Long-Term Outcomes in Japanese Patients Aged 80 Years or Older Undergoing Conventional Aortic Valve Replacement

    PubMed Central

    Osaka, Shunji; Yaoita, Hiroko; Ishii, Yusuke; Arimoto, Munehito; Hata, Hiroaki; Shiono, Motomi

    2015-01-01

    In this study, we investigated the early and long-term results of conventional aortic valve replacement (AVR) in very old patients. Methods: Seventy-five patients with aortic stenosis underwent conventional AVR for patients aged 80 years.We examined early death and major adverse cardiovascular and cerebrovascular event (MACCE). Results: The operative mortality was 0% for isolated AVR and 19.2% for concomitant surgery. The postoperative survival rate and MACCE free-rate were no significant differences between the isolated AVR and the concomitant surgery. Univariate analysis confirmed that cardiac dysfunction, severe chronic kidney disease (CKD), hemodialysis, + coronary artery bypass grafting, and norepinephrine use were risk factor of early death. Univariate analysis confirmed that severe CKD, BNP >1000 pg/ml, aortic cross clamping time (ACCT) >180 min, and non-use carperitide and multivariate analysis confirmed that ACCT >180 min, and non-use carperitide were risk factor of MACCE. Conclusions: This study showed that the results of conventional AVR in very old patients were not satisfactory. However, the results obtained with isolated AVR were favorable with no operative deaths. The present study demonstrated that preoperative cardiac function, preoperative renal function, and operative factors have an important impact on early mortality and MACCE. PMID:26004118

  14. New Directions for Early Literacy in a Digital Age: The iPad

    ERIC Educational Resources Information Center

    Flewitt, Rosie; Messer, David; Kucirkova, Natalia

    2015-01-01

    In this paper, we discuss how iPads offer innovative opportunities for early literacy learning but also present challenges for teachers and children. We lent iPads to a Children's Centre nursery (3- to 4-year-olds), a primary school reception class (4- to 5-year-olds) and a Special School (7- to 13-year-olds), discussed their potential uses with…

  15. The Early Cretaceous Sulfur Isotope Record: New Data, Revised Ages, and Updated Modeling

    NASA Astrophysics Data System (ADS)

    Kristall, B.; Hurtgen, M.; Sageman, B. B.; Jacobson, A. D.

    2015-12-01

    The Early Cretaceous is a time of significant transformation with the continued break-up of Pangea, the emplacement of several LIPs, and a climatic shift from a cool greenhouse to a warm greenhouse. The timing of these major events and their relationship to seawater geochemistry (as recorded in isotope records) is critical for understanding changes in global biogeochemical cycles during this time. Within this context, recent revisions to the Cretaceous portion of the geologic timescale necessitate a reevaluation of the Cretaceous S isotope record as recorded in marine barite (Paytan et al., 2004). We present a revised Early Cretaceous S isotope record and present new δ34Sbarite data that extend the record further back in time and provide more detail during two major S isotope shifts of the Early Cretaceous. The new data maintain the major ~5‰ negative shift but raise questions on the timing and structure of this perturbation. Furthermore, recently updated estimates for global rates of marine microbial sulfate reduction (MSR) (Bowles et al., 2014) and sulfate burial during the Phanerozoic (Halevy et al., 2012) require notable revisions in the fluxes and isotopic values used to model the global S cycle. We present a revised global S cycle box model and reconstruct the evolution of the Early Cretaceous S isotope record primarily through perturbations in volcanic and hydrothermal fluxes (e.g., submarine LIPs). Changes to the weathering and pyrite burial fluxes and the global integrated fractionation factor for MSR are also used to modulate, balance, and smooth the LIP-driven perturbation. The massive evaporite burial during the Late Aptian post dates the major -5‰ shift and has little affect on the modeled S isotope composition of seawater sulfate, despite causing a major drop in sulfate concentration. The S cycle box model is coupled to a Sr cycle box model to provide additional constraints on the magnitude and timing of perturbations within the S isotope record.

  16. The Prognostic Impact of Molecular Subtypes and Very Young Age on Breast Conserving Surgery in Early Stage Breast Cancer

    PubMed Central

    McGuire, Kandace; Alco, Gul; Nur Pilanci, Kezban; Koksal, Ulkuhan I; Elbüken, Filiz; Erdogan, Zeynep; Agacayak, Filiz; Ilgun, Serkan; Sarsenov, Dauren; Öztürk, Alper; İğdem, Şefik; Okkan, Sait; Eralp, Yeşim; Dincer, Maktav; Ozmen, Vahit

    2016-01-01

    Background Premenopausal breast cancer with a triple-negative phenotype (TNBC) has been associated with inferior locoregional recurrence free survival (LRFS) and overall survival (OS) after breast conserving surgery (BCS). The aim of this study is to analyze the association between age, subtype, and surgical treatment on survival in young women (≤40 years) with early breast cancer in a population with a high rate of breast cancer in young women. Methods Three hundred thirty-two patients ≤40 years old with stage I-II invasive breast cancer who underwent surgery at a single institution between 1998 and 2012 were identified retrospectively. Uni- and multivariate analysis evaluated predictors of LRFS, OS, and disease free survival (DFS). Results Most patients (64.2%) underwent BCS. Mean age and follow-up time were 35 (25 ± 3.61) years, and 72 months (range, 24–252), respectively. In multivariate analysis, multicentricity/multifocality and young age (<35 years) independently predicted for poorer DFS and OS. Those aged 35–40 years had higher LRFS and DFS than those <35 in the mastectomy group (p=0.007 and p=0.039, respectively). Patients with TNBC had lower OS compared with patients with luminal A subtype (p=0.042), and those who underwent BCS had higher OS than patients after mastectomy (p=0.015). Conclusion Young age (< 35 years) is an independent predictor of poorer OS and DFS as compared with ages 35–40, even in countries with a lower average age of breast cancer presentation. In addition, TNBC in the young predicts for poorer OS. BCS can be performed in young patients with TNBC, despite their poorer overall survival. PMID:27433412

  17. Infants born large-for-gestational-age display slower growth in early infancy, but no epigenetic changes at birth

    PubMed Central

    Chiavaroli, Valentina; Cutfield, Wayne S.; Derraik, José G. B.; Pan, Zengxiang; Ngo, Sherry; Sheppard, Allan; Craigie, Susan; Stone, Peter; Sadler, Lynn; Ahlsson, Fredrik

    2015-01-01

    We evaluated the growth patterns of infants born large-for-gestational-age (LGA) from birth to age 1 year compared to those born appropriate-for-gestational-age (AGA). In addition, we investigated possible epigenetic changes associated with being born LGA. Seventy-one newborns were classified by birth weight as AGA (10th–90th percentile; n = 42) or LGA (>90th percentile; n = 29). Post-natal follow-up until age 1 year was performed with clinical assessments at 3, 6, and 12 months. Genome-wide DNA methylation was analysed on umbilical tissue in 19 AGA and 27 LGA infants. At birth, LGA infants had greater weight (p < 0.0001), length (p < 0.0001), ponderal index (p = 0.020), as well as greater head (p < 0.0001), chest (p = 0.044), and abdominal (p = 0.007) circumferences than AGA newborns. LGA infants were still larger at the age of 3 months, but by age 6 months there were no more differences between groups, due to higher length and weight increments in AGA infants between 0 and 6 months (p < 0.0001 and p = 0.002, respectively). Genome-wide analysis showed no epigenetic differences between LGA and AGA infants. Overall, LGA infants had slower growth in early infancy, being anthropometrically similar to AGA infants by 6 months of age. In addition, differences between AGA and LGA newborns were not associated with epigenetic changes. PMID:26419812

  18. Age-Dependent Differences in the Strength and Persistence of Psychostimulant-Induced Conditioned Activity in Rats: Effects of a Single Environment-Cocaine Pairing

    PubMed Central

    McDougall, Sanders A.; Pipkin, Joseph A.; Der-Ghazarian, Taleen; Cortez, Anthony M.; Gutierrez, Arnold; Lee, Ryan J.; Carbajal, Sandra; Mohd-Yusof, Alena

    2014-01-01

    The purpose of the present study was to determine the strength and persistence of cocaine-induced conditioned activity in young and adult rats. A one-trial protocol has proven useful for studying the ontogeny of psychostimulant-induced behavioral sensitization; therefore, a similar procedure was used to examine conditioned activity. On postnatal day (PD) 19 or PD 80, rats were injected with saline or cocaine in either a novel test chamber or the home cage. After various drug abstinence intervals (1–21 days), rats were injected with saline and returned to the test chamber, where conditioned activity was assessed. In a separate experiment, we examined whether cocaine-induced conditioned activity was a consequence of Pavlovian conditioning or a failure to habituate to the test environment. The results showed that adult rats exhibited strong one-trial conditioned activity that persisted for at least 21 days, whereas young rats did not show a conditioned locomotor response. The conditioned activity exhibited by adult rats did not result from a failure to habituate to the cocaine-paired environment. These results indicate that cocaine-paired contextual stimuli differentially affect behavior depending on age of the animal. The data provided by adult rats have potential translational relevance for humans because a single environment-drug pairing caused long-term alterations in behavior. PMID:25171082

  19. Relationships of thigh muscle contractile and non-contractile tissue with function, strength, and age in boys with Duchenne muscular dystrophy.

    PubMed

    Akima, Hiroshi; Lott, Donovan; Senesac, Claudia; Deol, Jasjit; Germain, Sean; Arpan, Ishu; Bendixen, Roxanna; Lee Sweeney, H; Walter, Glenn; Vandenborne, Krista

    2012-01-01

    The purpose of this study was to assess the contractile and non-contractile content in thigh muscles of patients with Duchenne muscular dystrophy (DMD) and determine the relationship with functional abilities. Magnetic resonance images of the thigh were acquired in 28 boys with DMD and 10 unaffected boys. Muscle strength, timed functional tests, and the Brookes Lower Extremity scale were also assessed. Non-contractile content in the DMD group was significantly greater than in the control group for six muscles, including rectus femoris, biceps femoris-long head and adductor magnus. Non-contractile content in the total thigh musculature assessed by MRI correlated with the Brookes scale (r(s)=0.75) and supine-up test (r(s)=0.68), as well as other functional measures. An age-related specific torque increase was observed in the control group (r(s)=0.96), but not the DMD (r(s)=0.06). These findings demonstrate that MRI measures of contractile and non-contractile content can provide important information about disease progression in DMD. PMID:21807516

  20. Reliability and Validity of Field-Based Tests to Assess Upper-Body Muscular Strength in Children Aged 6-12 Years.

    PubMed

    Fernandez Santos, Jorge R; Ruiz, Jonatan R; Gonzalez-Montesinos, Jose Luis; Castro-Piñero, Jose

    2016-05-01

    The aim of this study was to analyze the reliability and the validity of the handgrip, basketball throw and pushups tests in children aged 6-12 years. One hundred and eighty healthy children (82 girls) agreed to participate in this study. All the upper body muscular fitness tests were performed twice (7 days apart) whereas the 1 repetition maximum (1RM) bench press test was performed 2 days after the first session of testing. All the tests showed a high reproducibility (ICC > 0.9) except the push-ups test (intertrial difference = 0.77 ± 2.38, p < .001 and the percentage error = 9%). The handgrip test showed the highest association with 1RM bench press test (r = .79, p < .01; R2 = .621). In conclusion the handgrip and basketball throw tests are shown as reliable and valid tests to assess upper body muscular strength in children. More studies are needed to assess the validity and the reliability of the upper body muscular endurance tests in children.

  1. Parent-Child Educational Centers: A Facility for Early Childhood Education Ages, Infancy to Seven Years.

    ERIC Educational Resources Information Center

    Arizona State Univ., Tempe.

    A Parent-Child Educational Center is a coordinating activity purposing to serve parents along with their children from a child's infancy through the age of seven. Such a center is carried on through the mutual initiative and involvement of parents and professional staff. The center serves parents by (1) providing for the developmental well-being…

  2. Menstrual Profile and Early Menopause in Women with Down Syndrome Aged 26-40 Years

    ERIC Educational Resources Information Center

    Ejskjaer, Kirsten; Uldbjerg, Niels; Goldstein, Henri

    2006-01-01

    Background: It is known that women with Down syndrome can be fertile, but it is not known whether all women with Down syndrome are fertile or sub-fertile. The age at menopause for women with Down syndrome is lower compared to women without Down syndrome. Method: A cross-sectional study of 11 women was undertaken, in which the participating women…

  3. Age at Assessment a Critical Factor When Monitoring Early Communicative Skills in Children with Galactosaemia

    ERIC Educational Resources Information Center

    Lewis, Fiona M.; DeJonge, Shannon M.; Coman, David J.

    2014-01-01

    Sub-optimal language development is associated with the metabolic disorder galactosaemia (GAL). Some children with GAL are identified with language impairment from the initial stages of language learning, but a subset of children may exhibit disrupted developmental gains in speech and language skill after a period of age-appropriate skill…

  4. A Case for Early Learning: An Invitational Environment for Children, Ages 3 - 6.

    ERIC Educational Resources Information Center

    Randazzo, Joseph D.

    The challenges facing education today, in particular the educational programs for children aged 3 to 6, are found to be many and varied, with the failures in urban settings pointing up the need for different and responsive learning environments. In the development of alternatives to current conditions in the schools today, the following are…

  5. Dietary restriction improves repopulation but impairs lymphoid differentiation capacity of hematopoietic stem cells in early aging.

    PubMed

    Tang, Duozhuang; Tao, Si; Chen, Zhiyang; Koliesnik, Ievgen Oleksandrovich; Calmes, Philip Gerald; Hoerr, Verena; Han, Bing; Gebert, Nadja; Zörnig, Martin; Löffler, Bettina; Morita, Yohei; Rudolph, Karl Lenhard

    2016-04-01

    Dietary restriction (DR) improves health, delays tissue aging, and elongates survival in flies and worms. However, studies on laboratory mice and nonhuman primates revealed ambiguous effects of DR on lifespan despite improvements in health parameters. In this study, we analyzed consequences of adult-onset DR (24 h to 1 yr) on hematopoietic stem cell (HSC) function. DR ameliorated HSC aging phenotypes, such as the increase in number of HSCs and the skewing toward myeloid-biased HSCs during aging. Furthermore, DR increased HSC quiescence and improved the maintenance of the repopulation capacity of HSCs during aging. In contrast to these beneficial effects, DR strongly impaired HSC differentiation into lymphoid lineages and particularly inhibited the proliferation of lymphoid progenitors, resulting in decreased production of peripheral B lymphocytes and impaired immune function. The study shows that DR-dependent suppression of growth factors and interleukins mediates these divergent effects caused by DR. Supplementation of insulin-like growth factor 1 partially reverted the DR-induced quiescence of HSCs, whereas IL-6/IL-7 substitutions rescued the impairment of B lymphopoiesis exposed to DR. Together, these findings delineate positive and negative effects of long-term DR on HSC functionality involving distinct stress and growth signaling pathways.

  6. Maternal Reminiscing Style during Early Childhood Predicts the Age of Adolescents' Earliest Memories

    ERIC Educational Resources Information Center

    Jack, Fiona; MacDonald, Shelley; Reese, Elaine; Hayne, Harlene

    2009-01-01

    Individual differences in parental reminiscing style are hypothesized to have long-lasting effects on children's autobiographical memory development, including the age of their earliest memories. This study represents the first prospective test of this hypothesis. Conversations about past events between 17 mother-child dyads were recorded on…

  7. The Acquisition of Accusative Object Clitics by IA Children from China: Evidence of Early Age Effects?

    ERIC Educational Resources Information Center

    Delcenserie, Audrey; Genesee, Fred

    2015-01-01

    The present study compared the performance of twenty-seven French-speaking internationally adopted (IA) children from China to that of twenty-seven monolingual non-adopted French-speaking children (CTL) matched for age, gender, and socioeconomic status on a Clitic Elicitation task. The IA children omitted significantly more accusative object…

  8. Intake of zinc and antioxidant micronutrients and early age-related maculopathy lesions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Macular degeneration, the end stage of age-related maculopathy (ARM), is the leading cause of legal blindness worldwide, and few modifiable risk factors are known. The high concentration of carotenoids in the macula, plus evidence linking oxidative stress to ARM, and carotenoids to antioxidation, ge...

  9. Is Early Joint Attention Associated with School-Age Pragmatic Language?

    ERIC Educational Resources Information Center

    Gillespie-Lynch, Kristen; Khalulyan, Allie; del Rosario, Mithi; McCarthy, Brigid; Gomez, Lovella; Sigman, Marian; Hutman, Ted

    2015-01-01

    In order to evaluate evidence for the social-cognitive theory of joint attention, we examined relations between initiation of and response to joint attention at 12 and 18 months of age and pragmatic and structural language approximately 6 years later among children with and without autism spectrum disorder. Initiation of joint attention at 18…

  10. Executive Control at an Early Age: Advance Planning in Solitary Play.

    ERIC Educational Resources Information Center

    Besevegis, Elias; Neimark, Edith D.

    Questions concerning the ontogeny of the planning process and its role in the regulation of behavior have been markedly absent from the literature. The present study examines the planning done during solitary play by middle-class children from four public nursery schools in Athens, Greece. One hundred preschool children in five age groups (42, 48,…

  11. Agricultural production and stability of settlement systems in Upper Mesopotamia during the Early Bronze Age (third millennium BCE)

    NASA Astrophysics Data System (ADS)

    Kalayci, Tuna

    This study investigates the relationship between rainfall variation and rain-fed agricultural production in Upper Mesopotamia with a specific focus on Early Bronze Age urban settlements. In return, the variation in production is used to explore stability of urban settlement systems. The organization of the flow of agricultural goods is the key to sustaining the total settlement system. The vulnerability of a settlement system increases due to the increased demand for more output from agricultural lands. This demand is the key for the success of urbanization project. However, without estimating how many foodstuffs were available at the end of a production cycle, further discussions on the forces that shaped and sustained urban settlement systems will be lacking. While large scale fluctuations in the flow of agricultural products between settlements are not the only determinants of hierarchical structures, the total available agricultural yield for each urban settlement in a hierarchy must have influenced settlement relations. As for the methodology, first, Early Bronze Age precipitation levels are estimated by using modern day associations between the eastern Mediterranean coastal areas and the inner regions of Upper Mesopotamia. Next, these levels are integrated into a remote-sensing based biological growth model. Also, a CORONA satellite imagery based archaeological survey is conducted in order to map the Early Bronze Age settlement system in its entirety as well as the ancient markers of agricultural intensification. Finally, ancient agricultural production landscapes are modeled in a GIS. The study takes a critical position towards the traditionally held assumption that large urban settlements (cities) in Upper Mesopotamia were in a state of constant demand for food. The results from this study also suggest that when variations in ancient precipitation levels are translated into the variations in production levels, the impact of climatic aridification on ancient

  12. Ancient DNA reveals a migration of the ancient Di-qiang populations into Xinjiang as early as the early Bronze Age.

    PubMed

    Gao, Shi-Zhu; Zhang, Ye; Wei, Dong; Li, Hong-Jie; Zhao, Yong-Bin; Cui, Yin-Qiu; Zhou, Hui

    2015-05-01

    Xinjiang is at the crossroads between East and West Eurasia, and it harbors a relatively complex genetic history. In order to better understand the population movements and interactions in this region, mitochondrial and Y chromosome analyses on 40 ancient human remains from the Tianshanbeilu site in eastern Xinjiang were performed. Twenty-nine samples were successfully assigned to specific mtDNA haplogroups, including the west Eurasian maternal lineages of U and W and the east Eurasian maternal lineages of A, C, D, F, G, Z, M7, and M10. In the male samples, two Y chromosome haplogroups, C* and N1 (xN1a, N1c), were successfully assigned. Our mitochondrial and Y-chromosomal DNA analyses combined with the archaeological studies revealed that the Di-qiang populations from the Hexi Corridor had migrated to eastern Xinjiang and admixed with the Eurasian steppe populations in the earl