Science.gov

Sample records for age determinations based

  1. Age determination of raccoons

    USGS Publications Warehouse

    Grau, G.A.; Sanderson, G.C.; Rogers, J.P.

    1970-01-01

    Age criteria, based on 61 skulls and eye lenses from 103 known-age captives, are described for separating raccoons (Procyon lotor) into eight age-classes as follows: young-of-the-year, 1, 2, 3, 4, 5, 6-7, > 7 years. Criteria studied were eye lens nitrogen, cranial suture closure, tooth wear and incisor cementum layers. Lens nitrogen increased rapidly up to 12 months of age, but at much reduced rate thereafter. Total lens nitrogen was useful only in separating young-of-the-year from adults. The closure sequence for five cranial sutures accurately divided the total known-age sample of males into seven groups, and the adults into five groups. The tooth wear criteria divided the known-age sample into five relative age groups, but aging of individuals by this method was inaccurate. Histological sectioning of known-age teeth was the best method of observing layering in the cementum tissue. The technique of basing estimation of age on cementum ring counts, although subjective, was accurate for aging individuals through their fourth year but tended to underestimate the age of animals over 4 years old. However, suture closure or tooth wear can be used to identify males over 4 years old. In field studies, technical difficulties limit the utility of age estimation by cementum layers. Maximum root thickness of the lower canine was accurate in determining the sex of individuals from 5 months to ,at least 48 months of age.

  2. Age determination by back length for African savanna elephants: extending age assessment techniques for aerial-based surveys.

    PubMed

    Trimble, Morgan J; van Aarde, Rudi J; Ferreira, Sam M; Nørgaard, Camilla F; Fourie, Johan; Lee, Phyllis C; Moss, Cynthia J

    2011-01-01

    Determining the age of individuals in a population can lead to a better understanding of population dynamics through age structure analysis and estimation of age-specific fecundity and survival rates. Shoulder height has been used to accurately assign age to free-ranging African savanna elephants. However, back length may provide an analog measurable in aerial-based surveys. We assessed the relationship between back length and age for known-age elephants in Amboseli National Park, Kenya, and Addo Elephant National Park, South Africa. We also compared age- and sex-specific back lengths between these populations and compared adult female back lengths across 11 widely dispersed populations in five African countries. Sex-specific Von Bertalanffy growth curves provided a good fit to the back length data of known-age individuals. Based on back length, accurate ages could be assigned relatively precisely for females up to 23 years of age and males up to 17. The female back length curve allowed more precise age assignment to older females than the curve for shoulder height does, probably because of divergence between the respective growth curves. However, this did not appear to be the case for males, but the sample of known-age males was limited to ≤27 years. Age- and sex-specific back lengths were similar in Amboseli National Park and Addo Elephant National Park. Furthermore, while adult female back lengths in the three Zambian populations were generally shorter than in other populations, back lengths in the remaining eight populations did not differ significantly, in support of claims that growth patterns of African savanna elephants are similar over wide geographic regions. Thus, the growth curves presented here should allow researchers to use aerial-based surveys to assign ages to elephants with greater precision than previously possible and, therefore, to estimate population variables.

  3. Age Determination by Back Length for African Savanna Elephants: Extending Age Assessment Techniques for Aerial-Based Surveys

    PubMed Central

    Trimble, Morgan J.; van Aarde, Rudi J.; Ferreira, Sam M.; Nørgaard, Camilla F.; Fourie, Johan; Lee, Phyllis C.; Moss, Cynthia J.

    2011-01-01

    Determining the age of individuals in a population can lead to a better understanding of population dynamics through age structure analysis and estimation of age-specific fecundity and survival rates. Shoulder height has been used to accurately assign age to free-ranging African savanna elephants. However, back length may provide an analog measurable in aerial-based surveys. We assessed the relationship between back length and age for known-age elephants in Amboseli National Park, Kenya, and Addo Elephant National Park, South Africa. We also compared age- and sex-specific back lengths between these populations and compared adult female back lengths across 11 widely dispersed populations in five African countries. Sex-specific Von Bertalanffy growth curves provided a good fit to the back length data of known-age individuals. Based on back length, accurate ages could be assigned relatively precisely for females up to 23 years of age and males up to 17. The female back length curve allowed more precise age assignment to older females than the curve for shoulder height does, probably because of divergence between the respective growth curves. However, this did not appear to be the case for males, but the sample of known-age males was limited to ≤27 years. Age- and sex-specific back lengths were similar in Amboseli National Park and Addo Elephant National Park. Furthermore, while adult female back lengths in the three Zambian populations were generally shorter than in other populations, back lengths in the remaining eight populations did not differ significantly, in support of claims that growth patterns of African savanna elephants are similar over wide geographic regions. Thus, the growth curves presented here should allow researchers to use aerial-based surveys to assign ages to elephants with greater precision than previously possible and, therefore, to estimate population variables. PMID:22028925

  4. [Determination of dental age].

    PubMed

    Willems, Guy

    2005-01-01

    A review of the most commonly used dental age estimating techniques is generated. The most important issue for the forensic odontologist involved in dental age estimation is to employ as many of these methods as possible by performing repetitive measurements and calculations of different age-related parameters. That is the only way in order to try and establish reliable dental age estimations. In particular, a special chapter is attributed to the complex problem of determining the age of majority. PMID:16370435

  5. HEU age determination

    SciTech Connect

    Moorthy, A.R.; Kato, W.Y.

    1995-08-01

    A technique has been developed to determine the Highly Enriched Uranium (HEU) Age which is defined as the time since the HEU was produced in an enrichment process. The HEU age is determined from the ratios of relevant uranium parents and their daughters viz {sup 230}Th/{sup 234}U and {sup 231}Pa/{sup 235}U. Uranium isotopes are quantitatively measured by their characteristic gammas and their daughters by alpha spectroscopy. In some of the samples where HEU is enriched more than 99%, the only mode of HEU age determination is by the measurement of {sup 231}Pa since there is negligible quantity of {sup 230}Th due to very low atom concentrations of {sup 234}U in the sample. In this paper we have presented data and methodology of finding the age of two HEU samples.

  6. HEU age determination

    SciTech Connect

    Moorthy, A.R.; Kato, W.Y.

    1997-07-01

    A new technique has been developed to determine the age of highly enriched uranium (HEU) in solids. Uranium age is defined as the time since the uranium-containing material was last subjected to a process capable of separating uranium from its radioactive-decay daughters. [Most chemical processing, uranium enrichment, volatilization processes, and phase transformations (especially relevant for uranium hexafluoride) can result in separation of the uranium parent material from the decay-product daughters.] Determination of the uranium age, as defined here, may be relevant in verifying arms-control agreements involving uranium-containing nuclear weapons. The HEU age is determined from the ratios of relevant uranium daughter isotopes and their parents, viz {sup 230}Th/{sup 234}U and {sup 231}Pa/{sup 235}U. Uranium isotopes are quantitatively measured by their characteristic gamma rays and their daughters by alpha spectroscopy. In some of the samples, where HEU is enriched more than 99%, the only mode of HEU age determination is by the measurement of {sup 231}Pa since there is negligible quantity of {sup 230}Th due to very low atom concentrations of {sup 234}U in the samples. In this report the methodology and the data for determining the age of two HEU samples are presented.

  7. HEU age determination

    SciTech Connect

    Moorthy, A.R.; Kato, W.Y.

    1994-12-31

    A criteria that a sample of highly enriched uranium (HEU) had come from a weapons stockpile and not newly produced in an enrichment plant is to show that the HEU had been produced a significant time in the past. The time since the HEU has produced in an enrichment plant is defined as the age of the HEU in this paper. The HEU age is determined by measuring quantitatively the daughter products {sup 230}Th and {sup 231}Pa of {sup 234}U and {sup 235}U, respectively, by first chemical separation of the thorium and protactinium and then conducting alpha spectrometry of the daughter products.

  8. Age determination of mallards

    USGS Publications Warehouse

    Krapu, G.L.; Johnson, D.H.; Dane, C.W.

    1979-01-01

    A technique for distinguishing adult from yearling wild mallards (Anas platyrhynchos), from late winter through the nesting season, was developed by applying discriminant analysis procedures to selected wing feather characters of 126 yearlings and 76 adults (2-year-olds) hand-reared from wild eggs during 1974, 1975, and 1977. Average values for feather characters generally increased as the birds advanced from yearlings to adults. Black-white surface area of greater secondary covert 2 was the single most reliable aging character identified during the study. The error rate was lowest in females (3%) when discriminant functions were used with measurements of primary 1 weight and black-white area of greater secondary covert 2 and in males (9%) when the functions were used with black-white area of greater secondary coverts 1, 2, and 3. Methodology precludes aging of birds in the field during capture operations.

  9. Age determinations and Earth-based multispectral observations of lunar light plains

    NASA Technical Reports Server (NTRS)

    Koehler, U.; Jaumann, R.; Neukum, G.

    1993-01-01

    The history of light plains still remains doubtful, but there are good arguments - mainly obtained by age determinations and supported by multispectral observations - for an endogenic (magmatic) instead of an (exclusively) impact related origin. Light plains are characterized by smooth areas with an albedo lower than the surrounding highlands (12 - 13 percent), but significantly higher than maria (5 - 6 percent). Before Apollo 16 a volcanic source has been supposed, but analysis of returned samples (highly brecciated and metamorphosed rocks) favored an impact ejecta related origin. Among the currently discussed models are formation by ejecta sedimentation from multi-ringed basins, formation by secondary and tertiary cratering action of ballistically ejected material during the formation of multi-ringed basins, in situ formation by impact melt of large events, and premare (crypto-) volcanism basalts covered by a thin ejecta cover; younger impacts penetrated the ejecta surface to create the dark haloed craters. To find arguments in favor or against these ideas the chronology of light plains is of major importance. Obviously a genetic relationship between the evolution of light plains and the basin forming impacts can be possible only if the events of emplacement features happened simultaneously.

  10. Determining 'age at death' for forensic purposes using human bone by a laboratory-based biomechanical analytical method.

    PubMed

    Zioupos, P; Williams, A; Christodoulou, G; Giles, R

    2014-05-01

    Determination of age-at-death (AAD) is an important and frequent requirement in contemporary forensic science and in the reconstruction of past populations and societies from their remains. Its estimation is relatively straightforward and accurate (±3yr) for immature skeletons by using morphological features and reference tables within the context of forensic anthropology. However, after skeletal maturity (>35yr) estimates become inaccurate, particularly in the legal context. In line with the general migration of all the forensic sciences from reliance upon empirical criteria to those which are more evidence-based, AAD determination should rely more-and-more upon more quantitative methods. We explore here whether well-known changes in the biomechanical properties of bone and the properties of bone matrix, which have been seen to change with age even after skeletal maturity in a traceable manner, can be used to provide a reliable estimate of AAD. This method charts a combination of physical characteristics some of which are measured at a macroscopic level (wet & dry apparent density, porosity, organic/mineral/water fractions, collagen thermal degradation properties, ash content) and others at the microscopic level (Ca/P ratios, osteonal and matrix microhardness, image analysis of sections). This method produced successful age estimates on a cohort of 12 donors of age 53-85yr (7 male, 5 female), where the age of the individual could be approximated within less than ±1yr. This represents a vastly improved level of accuracy than currently extant age estimation techniques. It also presents: (1) a greater level of reliability and objectivity as the results are not dependent on the experience and expertise of the observer, as is so often the case in forensic skeletal age estimation methods; (2) it is purely laboratory-based analytical technique which can be carried out by someone with technical skills and not the specialised forensic anthropology experience; (3) it can

  11. Determinant Factors of Anemia among Nonpregnant Women of Childbearing Age in Southwest Ethiopia: A Community Based Study

    PubMed Central

    Yemane, Tilahun; Gedefaw, Lealem

    2014-01-01

    Background. Anemia affects one-quarter of the world's population; nonpregnant women were one of the groups for whom it is common, making it a global public health problem. Objective. To determine prevalence and risk factors of anemia among nonpregnant women of childbearing age in Jimma town southwest Ethiopia. Methodology. We conducted a community based cross-sectional study involving 441 nonpregnant women. Data was collected over two months of period. We collected sociodemographic and related data using structured questionnaire. We collected four milliliters of venous blood and five grams of stool samples from each study participant for hematological and parasitological analysis. We performed statistical analysis using SPSS-V 16 software. Result. The prevalence of anemia was 16.1% (n = 71) with mean hemoglobin 12.96 g/dL (±1.04), among which 97.2% (n = 69) were mildly anemic. Age group of 25–36 years old, lower economic level, illiteracy, multiparity, having intestinal parasitic infection, using more than two sanitary pads per day during menstruation period, and low body mass index were found to be risk factors of anemia among the group. Conclusion. Prevalence of anemia indicates mild public health importance which shows it was indeed public health problem. Identified risk factors should be considered for prevention and control of anemia among the group. PMID:27355074

  12. USE OF SENSITIVITY ANALYSIS ON A PHYSIOLOGICALLY-BASED PHARMACOKINETIC (PBPK) MODEL FOR CHLOROFORM IN RATS TO DETERMINE AGE-RELATED TOXICITY

    EPA Science Inventory

    USE OF SENSITIVITY ANALYSIS ON A PHYSIOLOGICALLY BASED PHARMACOKINETIC (PBPK) MODEL FOR CHLOROFORM IN RATS TO DETERMINE AGE-RELATED TOXICITY.
    CR Eklund, MV Evans, and JE Simmons. US EPA, ORD, NHEERL, ETD,PKB, Research Triangle Park, NC.

    Chloroform (CHCl3) is a disinfec...

  13. Age determination of female redhead ducks

    USGS Publications Warehouse

    Dane, C.W.; Johnson, D.H.

    1975-01-01

    Eighty-seven fall-collected wings from female redhead ducks (Aythya americana) were assigned to the adult or juvenile group based on 'tertial' and 'tertial covert' shape and wear. To obtain spring age-related characters from these fall-collected groupings, we considered parameters of flight feathers retained until after the first breeding season. Parameters measured included: markings on and width of greater secondary coverts, and length, weight, and diameter of primary feathers. The best age categorization was obtained with discriminant analysis based on a combination of the most accurately measured parameters. This analysis, applied to 81 wings with complete measurements, resulted in only 1 being incorrectly aged and 3 placed in a questionable category. Discriminant functions used with covert markings and the three 5th primary parameters were applied to 30 known-age juvenile, hand-reared redhead females, 28 were correctly aged, none was incorrectly aged, and only 2 were placed in the questionable category.

  14. Age as independent determinant of glucose tolerance.

    PubMed

    Shimokata, H; Muller, D C; Fleg, J L; Sorkin, J; Ziemba, A W; Andres, R

    1991-01-01

    It has been proposed that the decline in glucose tolerance with age is not a primary aging effect but is secondary to a combination of other age-associated characteristics, i.e., disease, medication, obesity, central and upper-body fat deposition, and inactivity. To test this hypothesis, we first eliminated from analysis the Baltimore Longitudinal Study of Aging participants with identifiable diseases or medications known to influence glucose tolerance. Seven hundred forty-three men and women, aged 17-92 yr, remained for analysis. As indices of fatness, body mass index and percent body fat were determined. As indices of body fat distribution, waist-hip ratio and subscapular triceps skin-fold ratio were calculated. As indices of fitness, physical activity level, determined by detailed questionnaire, and maximum 02 consumption were calculated. We tested whether the effect of age on glucose tolerance remains when data were adjusted for fatness, fitness, and fat distribution; 2-h glucose values were 6.61, 6.78, and 7.83 mM for young (17-39 yr), middle-aged (40-59 yr), and old (60-92 yr) men and 6.22, 6.22, and 7.28 mM for the three groups of women, respectively. The differences between the young and middle-aged groups were not significant, but the old groups had significantly higher values than young or middle-aged groups. Fatness, fitness, and fat distribution can account for the decline in glucose tolerance from the young adult to the middle-aged years. However, age remains a significant determinant of the further decline in glucose tolerance of healthy old subjects.

  15. The Social Determinants of Health in Association with Women’s Health Status of Reproductive Age: A Population-Based Study

    PubMed Central

    BAHEIRAEI, Azam; BAKOUEI, Fatemeh; MOHAMMADI, Eesa; MONTAZERI, Ali; HOSSENI, Mostafa

    2015-01-01

    Abstract Background Prioritizing women’s health helps achievement of the 4th and 5th goals of Millennium Development Program. This study aimed to investigate association between social determinants of health and women’s health of reproductive age. Methods This population-based cross-sectional study, using multi-stage sampling procedure was conducted on 770, 15 to 49-year-old women residing in any one of the 22 municipality zones across Tehran, Iran. Eligible women were interviewed at home with SF-36 (Short Form Health Survey) and socio-demographic questionnaires. Social determinants of health contains; ethnicity, education, job, income, and crowding index. Data were analyzed by ANOVA and Multiple Linear Regression using SPSS-16. The threshold of P.V was considered 0.05. Results Overall, 770 women with mean age 33.9±9.3 years were interviewed. Majority of them were married (72.27%), housewives (62.2%), of Persian ethnicity (64.3%), and educated to high school level (43.8%). Age with dimensions of health except role emotional, mental health, and social functioning had significant association with B from -0.65 to -0.16.educational level with dimensions of health except role emotional andsocial functioning had significant association with B from 3.61 to 6.43 (P<0.05). Income with dimensions of health except role physical had significant association with B from -9.97 to -4.42. Conclusion Reflection of unfavorable economic conditions and low education level on negative women’ health experiences are alarming. Interaction between social determinants of health and health status must be considered in policymaking, and there is a need for policies that would enhance health of women in the low education and income brackets. PMID:26060783

  16. Asteroseismic age determination for dwarfs and giants

    NASA Astrophysics Data System (ADS)

    Silva Aguirre, V.; Serenelli, A. M.

    2016-09-01

    Asteroseismology can make a substantial contribution to our understanding of the formation history and evolution of our Galaxy by providing precisely determined stellar properties for thousands of stars in different regions of the Milky Way. We present here the different sets of observables used in determining asteroseismic stellar properties, the typical level of precision obtained, the current status of results for ages of dwarfs and giants, and the improvements than can be expected in the near future in the context of Galactic archaeology.

  17. Age determination in juvenile bobwhite quail

    USGS Publications Warehouse

    Petrides, G.A.; Nestler, R.B.

    1943-01-01

    Following methods described by Louis Bureau (1911, 1913) in France,tabulations were made (1) of the ages at which captivity-reared bob-white quail (Colinus virginianus) dropped their juvenal remiges, and (2) the rates at which post-juvenal replxcement primaries grew. These were arranged so as to permit the determination of age in healthv birds from one to five months of age. The degree of individual variation was much greater than that found by Bureau, however. and limits accuracy in age determination after the 10th week..... The post-juvenal wing molt began on the birds' 28th day and ended when the quail were 146 to 154 days old.The post-juvenal body molt was found to take place largely between the 70th and 100th days. The juvenal rectrices were renewed from the 62nd to the 122nd days, the new feathers being as long as their longest coverts when the birds were 116 days old. The color of the tarsi varied from pink, at 32 days of age, to straw color at 60 days, and yellow-gray from 83 to 180 days. At six months, the color of the beak was identical with that of adults.....Unlike several other game bird species, the flexibility of the lower jaw was not an accurate index to age in bob-whites older than 11 weeks. Rigor mortis and freezing were found to hinder the testing of this criterion.

  18. Age determination of blue-winged teal

    USGS Publications Warehouse

    Dane, C.W.

    1968-01-01

    Primary feather length, markings on the greater secondary coverts, and the degree of bill spotting were evaluated as characters for use in the spring to distinguish first-year, blue-winged teal (Anas discors) females from older ones. The length of the 10th primary feather did not prove suitable to separate different aged females. Extreme primary lengths might be used to determine the age of some males. In females that have been through a postnuptial molt the greater secondary coverts have a more symmetrical, and more acutely angled, white, inverted 'V'-marking. Any female with a 'V' subjectively classified as good has gone through at least one postnuptial molt, and a female with no sign of a 'V' on the coverts is a juvenile or yearling before her first postnuptial molt. By measuring the longest bill spot on the upper mandible of each known-age female, it was possible to determine the age of some female teal. Because the spots fade during the breeding season, no lower size limit could be set to delineate first-year females at that time of year, but any nest-trapped hen with a spot longer than 10 mm was considered to be older than 1 year. Upper and lower limits were also established to distinguish some yearlings and 2-year-olds in the fall.

  19. Determining age and sex of American coots

    USGS Publications Warehouse

    Eddleman, William R.; Knopf, Fritz L.

    1985-01-01

    Reliable techniques for age and sex determination of migrating and wintering American Coots (Fulica americana) have not been available. Breeding coots can be ages through age 3 by tarsal color (birds 4 years and older were placed in a 4+ age class) (Crawford 1978), and males and females have sex-specific behaviors and calls while on breeding territories (Gullion 1950, 1952). Externally, juvenile coots differ from adults in having gray (as opposed to white) bills and brown (as opposed to red) eyes to an age of 75 days (Gullion 1954-394). Bill color changes to white by about 120 days. No quantitative data have been available, however, on the proportion of juveniles retaining these traits throughout fall and early winter. Nonbreeding coots can be ages as juvenile or adult by internal examination of the thickness of the wall of the bursa of Fabricius, although bursal depth does not predictably decline with age (Fredrickson 1968). Attempts to sex coots by single external measurements of combinations of measurements have met with mixed success. Eight-five percent of 101 fall migrants in Wisconsin could be sexed by the length of the metatarsus-midtoe including claw by using 139.5 mm as a cutoff point (Burton 1959), whereas 88% of 67 coots in California were correctly sexed by the length of the metatarsus-midtoe without claw using 127.5 mm as the cutoff point (Gullion 1952). Two-hundred-thirty-two of 291 coots collected in Iowa, however, were in the zone of overlap between the sexes for this measurement (Fredrickson 1968). Previous studies attempting to develop aging and sexing techniques for American Coots have been limited to a few study sites or to 1 season or year, often failing to take geographical, annual, and seasonal morphological variation into account (e.g., Visser 1976, Fjeldsa 1977). We designed the present study to refine and quantify external and internal age and sex criteria for postbreeding coots, with the objective of defining techniques applicable for all

  20. Evaluation of age determination techniques for gray wolves

    USGS Publications Warehouse

    Landon, D.B.; Waite, C.A.; Peterson, R.O.; Mech, L.D.

    1998-01-01

    We evaluated tooth wear, cranial suture fusion, closure of the canine pulp cavity, and cementum annuli as methods of age determination for known- and unknown-age gray wolves (Canis lupus) from Alaska, Minnesota, Ontario, and Isle Royale, Michigan. We developed age classes for cranial suture closure and tooth wear. We used measurement data obtained from known-age captive and wild wolves to generate a regression equation to predict age based on the degree of closure of the canine pulp cavity. Cementum annuli were studied in known- and unknown-age animals, and calcified, unstained thin sections were found to provide clear annulus patterns under polarized transmitted light. Annuli counts varied among observers, partly because of variation in the pattern of annuli in different regions of the cementum. This variation emphasizes the need for standardized models of cementum analysis. Cranial suture fusion is of limited utility in age determination, while tooth wear can be used to estimate age of adult wolves within 4 years. Wolves lt 7 years old could be aged to within 13 years with the regression equation for closure of the canine pulp cavity. Although inaccuracy remains a problem, cementum-annulus counts were the most promising means of estimating age for gray wolves.

  1. 42 CFR 436.522 - Determination of age.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Determination of age. 436.522 Section 436.522... Requirements for Medicaid Eligibility Age § 436.522 Determination of age. (a) In determining age, the agency must use the common law method (under which an age is reached the day before the anniversary of...

  2. 42 CFR 436.522 - Determination of age.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Determination of age. 436.522 Section 436.522... Requirements for Medicaid Eligibility Age § 436.522 Determination of age. (a) In determining age, the agency must use the common law method (under which an age is reached the day before the anniversary of...

  3. 42 CFR 436.522 - Determination of age.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Determination of age. 436.522 Section 436.522... Requirements for Medicaid Eligibility Age § 436.522 Determination of age. (a) In determining age, the agency must use the common law method (under which an age is reached the day before the anniversary of...

  4. 42 CFR 436.522 - Determination of age.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Determination of age. 436.522 Section 436.522... Requirements for Medicaid Eligibility Age § 436.522 Determination of age. (a) In determining age, the agency must use the common law method (under which an age is reached the day before the anniversary of...

  5. 42 CFR 436.522 - Determination of age.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Determination of age. 436.522 Section 436.522... Requirements for Medicaid Eligibility Age § 436.522 Determination of age. (a) In determining age, the agency must use the common law method (under which an age is reached the day before the anniversary of...

  6. Nutritional determinants of cognitive aging and dementia.

    PubMed

    Morris, Martha C

    2012-02-01

    The objective of this review is to provide an overview of nutritional factors involved in cognitive aging and dementia with a focus on nutrients that are also important in neurocognitive development. Several dietary components were targeted, including antioxidant nutrients, dietary fats and B-vitamins. A critical review of the literature on each nutrient group is presented, beginning with laboratory and animal studies of the underlying biological mechanisms, followed by prospective epidemiological studies and randomised clinical trials. The evidence to date is fairly strong for protective associations of vitamin E from food sources, the n-3 fatty acid, DHA, found in fish, a high ratio of polyunsaturated to saturated fats, and vitamin B12 and folate. Attention to the level of nutrient intake is crucial for interpreting the literature and the inconsistencies across studies. Most of the epidemiological studies that observe associations have sufficient numbers of individuals who have both low and adequate nutrient status. Few of the randomised clinical trials are designed to target participants who have low baseline status before randomising to vitamin supplement treatments, and this may have resulted in negative findings. Post-hoc analyses by some of the trials reveal vitamin effects in individuals with low baseline intakes. The field of diet and dementia is a relatively young area of study. Much further work needs to be done to understand dietary determinants of cognitive aging and diseases. Further, these studies must be particularly focused on the levels of nutrient intake or status that confer optimum or suboptimal brain functioning.

  7. 42 CFR 435.522 - Determination of age.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Determination of age. 435.522 Section 435.522... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Age § 435.522 Determination of age. (a) Except as specified in paragraphs (b) and (c) of this section, in determining age, the...

  8. 42 CFR 435.522 - Determination of age.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Determination of age. 435.522 Section 435.522... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Age § 435.522 Determination of age. (a) Except as specified in paragraphs (b) and (c) of this section, in determining age, the...

  9. 42 CFR 435.522 - Determination of age.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Determination of age. 435.522 Section 435.522... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Age § 435.522 Determination of age. (a) Except as specified in paragraphs (b) and (c) of this section, in determining age, the...

  10. 42 CFR 435.522 - Determination of age.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Determination of age. 435.522 Section 435.522... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Age § 435.522 Determination of age. (a) Except as specified in paragraphs (b) and (c) of this section, in determining age, the...

  11. 42 CFR 435.522 - Determination of age.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Determination of age. 435.522 Section 435.522... ISLANDS, AND AMERICAN SAMOA Categorical Requirements for Eligibility Age § 435.522 Determination of age. (a) Except as specified in paragraphs (b) and (c) of this section, in determining age, the...

  12. Determinants of linear growth from infancy to school-aged years: a population-based follow-up study in urban Amazonian children

    PubMed Central

    2012-01-01

    Background Although linear growth during childhood may be affected by early-life exposures, few studies have examined whether the effects of these exposures linger on during school age, particularly in low- and middle-income countries. Methods We conducted a population-based longitudinal study of 256 children living in the Brazilian Amazon, aged 0.1 y to 5.5 y in 2003. Data regarding socioeconomic and maternal characteristics, infant feeding practices, morbidities, and birth weight and length were collected at baseline of the study (2003). Child body length/height was measured at baseline and at follow-up visits (in 2007 and 2009). Restricted cubic splines were used to construct average height-for-age Z score (HAZ) growth curves, yielding estimated HAZ differences among exposure categories at ages 0.5 y, 1 y, 2 y, 5 y, 7 y, and 10 y. Results At baseline, median age was 2.6 y (interquartile range, 1.4 y–3.8 y), and mean HAZ was −0.53 (standard deviation, 1.15); 10.2% of children were stunted. In multivariable analysis, children in households above the household wealth index median were 0.30 Z taller at age 5 y (P = 0.017), and children whose families owned land were 0.34 Z taller by age 10 y (P = 0.023), when compared with poorer children. Mothers in the highest tertile for height had children whose HAZ were significantly higher compared with those of children from mothers in the lowest height tertile at all ages. Birth weight and length were positively related to linear growth throughout childhood; by age 10 y, children weighing >3500 g at birth were 0.31 Z taller than those weighing 2501 g to 3500 g (P = 0.022) at birth, and children measuring ≥51 cm at birth were 0.51 Z taller than those measuring ≤48 cm (P = 0.005). Conclusions Results suggest socioeconomic background is a potentially modifiable predictor of linear growth during the school-aged years. Maternal height and child’s anthropometric characteristics at birth are positively

  13. Age determination of subdural hematomas: survey among radiologists.

    PubMed

    Postema, F A M; Sieswerda-Hoogendoorn, Tessa; Majoie, C B L M; van Rijn, R R

    2014-08-01

    Abusive head trauma is a severe form of child abuse. One important diagnostic finding is the presence of a subdural hematoma. Age determination of subdural hematomas is important to relate radiological findings to the clinical history presented by the caregivers. In court this topic is relevant as dating subdural hematomas can lead to identification of a suspect. The aim of our study is to describe the current practice among radiologists in the Netherlands regarding the age determination of subdural hematomas in children. This is a cross-sectional study, describing the results of an online questionnaire regarding dating subdural hematomas among pediatric and neuro-radiologists in the Netherlands. The questionnaire consisted of sociodemographic questions, theoretical questions and eight pediatric cases in which the participants were asked to date subdural hematomas based on imaging findings. Fifty-one out of 172 radiologists (30 %) filled out the questionnaire. The percentage of participants that reported it was possible to date the subdural hematoma varied between 58 and 90 % for the eight different cases. In four of eight cases (50 %), the age of the subdural hematoma as known from clinical history fell within the range reported by the participants. None of the participants was "very certain" of their age determination. The results demonstrate that there is a considerable practice variation among Dutch radiologists regarding the age determination of subdural hematomas. This implicates that dating of subdural hematomas is not suitable to use in court, as no uniformity among experts exists. PMID:24553773

  14. Evidence of synmagmatic foliation in the Selawik Hills, NW Alaska, based on [sup 40]Ar/[sup 39]Ar age determinations

    SciTech Connect

    Solie, D.N. ); Layer, P.W. . Geophysical Inst.)

    1993-04-01

    Based on [sup 40]Ar/[sup 39]Ar plateau ages from various rock units in the Selawik Hills plutonic complex, northwestern Alaska, the units were emplaced in the order syenite/monzonite, followed by nepheline syenite and then quartz monzonite. There is no evidence of disturbance of the Ar isotopic system in the dated plutonic minerals, and the ages compare fairly well with previously published K/Ar data. A cooling history of about ten m.y. for the Selawk Hills rocks is suggested, based on comparison of [sup 40]Ar/[sup 39]Ar ages with apatite fission-track data (Murphy and Till, 1992). Comparison of hornblende plateau ages between nonfoliated and foliated syenite indicates that foliated rocks crystallized later than nonfoliated rocks, but within the initial cooling history of the complex. Foliated syenite/monzonite has mineralogy similar to nonfoliated, but with generally higher color index. Foliated textures are distributed throughout the complex, but are more prevalent to the north, proximal to a large (about 2 km[sup 2]) xenolithic metamorphic block which is bounded on the north by an east-west-trending fault. The authors suggest that synmagmatic fault movement acted as a mechanism causing plutonic foliation and resulting in possible loss of late fluid from semicrystallized syenitic magma to form kspar-rich dikes. Foundering of the xenolithic block within the magma may also have contributed to development of foliation. Continued fault movement is indicated by cataclastic deformation along the fault trace.

  15. 27 CFR 19.328 - Determining age of mingled spirits.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Determining age of mingled... for Mingling Or Blending Spirits § 19.328 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot will be the age of the youngest spirits contained in the...

  16. 27 CFR 19.348 - Determining age of mingled spirits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Determining age of mingled... Spirits § 19.348 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot shall be the age of the youngest spirits contained in the lot. (Sec. 201, Pub. L....

  17. 27 CFR 19.328 - Determining age of mingled spirits.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Determining age of mingled... for Mingling Or Blending Spirits § 19.328 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot will be the age of the youngest spirits contained in the...

  18. 27 CFR 19.328 - Determining age of mingled spirits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Determining age of mingled... for Mingling Or Blending Spirits § 19.328 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot will be the age of the youngest spirits contained in the...

  19. 27 CFR 19.328 - Determining age of mingled spirits.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Determining age of mingled... for Mingling Or Blending Spirits § 19.328 Determining age of mingled spirits. When spirits are mingled, the age of the spirits for the entire lot will be the age of the youngest spirits contained in the...

  20. Determining Ages of APOGEE Giants with Known Distances

    NASA Astrophysics Data System (ADS)

    Feuillet, Diane; Bovy, Jo; Holtzman, Jon A.; Girardi, Leo; APOGEE Team

    2016-01-01

    We present a sample of 705 local (d <400 pc) red giant stars observed using the New Mexico State University 1m telescope with the SDSS-III APOGEE spectrograph, for which we estimate stellar ages and the age distribution from the high-resolution spectroscopic stellar parameters and accurate distance measurements from Hipparcos. The high-resolution (R ~ 23,000), near infrared (H-band, 1.5-1.7 μm) APOGEE spectra provide measurements of the stellar atmospheric parameters (temperature, surface gravity, [M/H], and [α/M]). Due to the smaller uncertainties in surface gravity possible with high-resolution spectra and accurate Hipparcos distance measurements, we are able to calculate the stellar masses to within 40 %. For red giants, the relatively rapid evolution of stars up the red giant branch allows the age to be constrained based on the mass. We examine methods of estimating age using both the mass-age relation directly and a Bayesian isochrone matching of measured parameters, assuming a constant SFH. To improve the prior on the SFH, we use a hierarchical modeling approach to constrain the parameters of a model SFH from the age probability distribution functions of the data. The results of an α-dependent Gaussian SFH model shows a clear relation between age and [α/M] at all ages. Using this SFH model as the prior for an empirical Bayesian analysis, we construct a full age probability distribution function and determine ages for individual stars. The age-metallicity relation is flat, with a slight decrease in [M/H] at the oldest ages and a ~ 0.5 dex spread in metallicity. For stars with ages > 1 Gyr we find a smaller spread, consistent with radial migration having a smaller effect on these young stars than on the older stars. This method of estimating ages of red giants is developed with the intent of estimating ages for the much larger sample of APOGEE survey giants that will have parallax measurements from Gaia.

  1. Determinants of iron accumulation in the normal aging brain.

    PubMed

    Pirpamer, Lukas; Hofer, Edith; Gesierich, Benno; De Guio, François; Freudenberger, Paul; Seiler, Stephan; Duering, Marco; Jouvent, Eric; Duchesnay, Edouard; Dichgans, Martin; Ropele, Stefan; Schmidt, Reinhold

    2016-07-01

    In a recent postmortem study, R2* relaxometry in gray matter (GM) of the brain has been validated as a noninvasive measure for iron content in brain tissue. Iron accumulation in the normal aging brain is a common finding and relates to brain maturation and degeneration. The goal of this study was to assess the determinants of iron accumulation during brain aging. The study cohort consisted of 314 healthy community-dwelling participants of the Austrian Stroke Prevention Study. Their age ranged from 38-82 years. Quantitative magnetic resonance imaging was performed on 3T and included R2* mapping, based on a 3D multi-echo gradient echo sequence. The median of R2* values was measured in all GM regions, which were segmented automatically using FreeSurfer. We investigated 25 possible determinants for cerebral iron deposition. These included demographics, brain volume, lifestyle factors, cerebrovascular risk factors, serum levels of iron, and single nucleotide polymorphisms related to iron regulating genes (rs1800562, rs3811647, rs1799945, and rs1049296). The body mass index (BMI) was significantly related to R2* in 15/32 analyzed brain regions with the strongest correlations found in the amygdala (p = 0.0091), medial temporal lobe (p = 0.0002), and hippocampus (p ≤ 0.0001). Further associations to R2* values were found in deep GM for age and smoking. No significant associations were found for gender, GM volume, serum levels of iron, or iron-associated genetic polymorphisms. In conclusion, besides age, the BMI and smoking are the only significant determinants of brain iron accumulation in normally aging subjects. Smoking relates to iron deposition in the basal ganglia, whereas higher BMI is associated with iron content in the neocortex following an Alzheimer-like distribution. PMID:27255824

  2. Mallard age and sex determination from wings

    USGS Publications Warehouse

    Carney, S.M.; Geis, A.D.

    1960-01-01

    This paper describes characters on the wing plumage of the mallard that indicate age and sex. A key outlines a logical order in which to check age and sex characters on wings. This method was tested and found to be more than 95 percent reliable, although it was found that considerable practice and training with known-age specimens was required to achieve this level of accuracy....The implications of this technique and the sampling procedure it permits are discussed. Wing collections could provide information on production, and, if coupled with a banding program could permit seasonal population estimates to be calculated. In addition, representative samples of wings would provide data to check the reliability of several other waterfowl surveys.

  3. Age-class determination of canvasbacks

    USGS Publications Warehouse

    Serie, J.R.; Trauger, D.L.; Doty, H.A.; Sharp, D.E.

    1982-01-01

    A technique was developed to distinguish yearling from adult canvasbacks (Aythya valisineria) in the field during spring on the basis of white flecking on the distal ends of selected wing feathers. Covert feathers from adults had well-defined vermiculation patterns whereas feathers from yearlings lacked such markings. These age-related characters were confirmed by paired comparisons of feathers from the same captive birds in consecutive years and by discriminant analysis of feathers using densitometric measurements from known-age wild birds. Reflective densitometric measurements of greater secondary coverts for females and males were significantly different between 1- and 2-year-old and between 2- and 3-year-old canvasbacks. Greater secondary coverts were the best feathers for recognizing age-classes of males and females. Densitometric values indicate low variability among different observers and within samples.

  4. Towards global age-friendly cities: determining urban features that promote active aging.

    PubMed

    Plouffe, Louise; Kalache, Alexandre

    2010-09-01

    At the same time as cities are growing, their share of older residents is increasing. To engage and assist cities to become more "age-friendly," the World Health Organization (WHO) prepared the Global Age-Friendly Cities Guide and a companion "Checklist of Essential Features of Age-Friendly Cities". In collaboration with partners in 35 cities from developed and developing countries, WHO determined the features of age-friendly cities in eight domains of urban life: outdoor spaces and buildings; transportation; housing; social participation; respect and social inclusion; civic participation and employment; communication and information; and community support and health services. In 33 cities, partners conducted 158 focus groups with persons aged 60 years and older from lower- and middle-income areas of a locally defined geographic area (n = 1,485). Additional focus groups were held in most sites with caregivers of older persons (n = 250 caregivers) and with service providers from the public, voluntary, and commercial sectors (n = 515). No systematic differences in focus group themes were noted between cities in developed and developing countries, although the positive, age-friendly features were more numerous in cities in developed countries. Physical accessibility, service proximity, security, affordability, and inclusiveness were important characteristics everywhere. Based on the recurring issues, a set of core features of an age-friendly city was identified. The Global Age-Friendly Cities Guide and companion "Checklist of Essential Features of Age-Friendly Cities" released by WHO serve as reference for other communities to assess their age readiness and plan change.

  5. Determinants of Muscle and Bone Aging.

    PubMed

    Curtis, Elizabeth; Litwic, Anna; Cooper, Cyrus; Dennison, Elaine

    2015-11-01

    Loss of bone and muscle with advancing age represent a huge threat to loss of independence in later life. Osteoporosis represents a major public health problem through its association with fragility fractures, primarily of the hip, spine and distal forearm. Sarcopenia, the age related loss of muscle mass and function, may add to fracture risk by increasing falls risk. In the context of muscle aging, it is important to remember that it is not just a decline in muscle mass which contributes to the deterioration of muscle function. Other factors underpinning muscle quality come into play, including muscle composition, aerobic capacity and metabolism, fatty infiltration, insulin resistance, fibrosis and neural activation. Genetic, developmental, endocrine and lifestyle factors, such as physical activity, smoking and poor diet have dual effects on both muscle and bone mass in later life and these will be reviewed here. Recent work has highlighted a possible role for the early environment. Inflammaging is an exciting emerging research field that is likely to prove relevant to future work, including interventions designed to retard to reverse bone and muscle loss with age. PMID:25820482

  6. Determinants of muscle and bone aging

    PubMed Central

    Curtis, E; Litwic, A; Cooper, C; Dennison, E

    2015-01-01

    Loss of bone and muscle with advancing age represent a huge threat to loss of independence in later life. Osteoporosis represents a major public health problem through its association with fragility fractures, primarily of the hip, spine and distal forearm. Sarcopenia, the age related loss of muscle mass and function, may add to fracture risk by increasing falls risk. In the context of muscle aging, it is important to remember that it is not just a decline in muscle mass which contributes to the deterioration of muscle function. Other factors underpinning muscle quality come into play, including muscle composition, aerobic capacity and metabolism, fatty infiltration, insulin resistance, fibrosis and neural activation. Genetic, developmental, endocrine and lifestyle factors, such as physical activity, smoking and poor diet have dual effects on both muscle and bone mass in later life and these will be reviewed here. These include poor nutrition, lack of physical activity and cigarette smoking, comorbidities or medication use. Recent work has highlighted a possible role for the early environment. Inflammaging is an exciting emerging research field that is likely to prove relevant to future work, including interventions designed to retard to reverse bone and muscle loss with age. PMID:25820482

  7. Determining optimum age of Holstein dairy calves when adding chopped alfalfa hay to meal starter diets based on measures of growth and performance.

    PubMed

    Hosseini, S M; Ghorbani, G R; Rezamand, P; Khorvash, M

    2016-04-01

    The present study was conducted to determine the optimum age of Holstein dairy calves for an effective inclusion of alfalfa hay (AH) in starter feed on performance, apparent digestibility and feeding behavior. A total of 40 Holstein dairy calves (20 female and 20 male) were used in a completely randomized design in which calves were randomly assigned to one of four different dietary treatments including control (CON) calves fed starter feed without any forage and three treatments consisting of the same starter feed plus 15% chopped AH fed when calves were at the 2nd (AH2), 4th (AH4) or 6th (AH6) week of age. Calves were individually housed and bedded with sand that was replaced every other day. Feed and water were available ad libitum throughout the experiment. Calves were fed milk at 10% of birth BW twice daily until d 57. The study concluded when calves were 73 days old. Starter intake was recorded daily and BW was measured weekly. Data were analyzed as a complete randomized design by MIXED procedures of SAS. Results demonstrate that calves receiving AH treatments numerically consumed more starter feed (0.62 v. 0.78, 0.71 and 0.65 kg/day for CON, AH2, AH4 and AH6, respectively) and had greater average daily gain (ADG) compared with CON (0.48 v. 0.57, 0.49 and 0.49 kg/day for CON, AH2, AH4 and AH6), although the significant difference was observed only between AH2 and CON. Among AH treatments, calves in AH2 had better performance than AH6 in several cases including starter intake, ADG. No detectable differences were observed, however, in apparent dry matter, organic matter or CP digestibility among treatments. Ruminal pH and NH3 concentrations, measured on weeks 4, 6, 8 and 10, were lower for calves fed CON compared with other treatments, with ammonia concentrations decreasing over time. Calves in the AH treatments spent more time eating and ruminating compared with CON. Calves fed CON, however, spent more time on laying down compared with other treatments

  8. Late exhumation of the Bergell pluton (Italian Alps): tectonics, climate change or Messinian base level drop? Insights from apatite (U-Th)/He ages determination and modeling.

    NASA Astrophysics Data System (ADS)

    Mahéo, Gweltaz; Gautheron, Cécile; Hervé Leloup, Philippe; Tassant-Got, Laurent; Douville, Eric

    2010-05-01

    The Bergell pluton, is an elongated-shape granodioritic to tonalitic body emplaced during Oligocene time at 30-32 Ma along the Insubric Line in the south-central Alps. This intrusion is located immediately north of the Insubric fault, within a bloc delimited by a major strike slip and normal faults related to the eastward extrusion of the central and eastern Alps. The range lies north of the Italian great lakes, an area where the erosion related to the Messinian base-level drop is supposedly strong. In order to reconstruct the Miocene exhumation history of this pluton and to place constraints on the effect of Messinian base-level drop on erosion and uplift, we performed (U-Th)/He dating of 10 apatite samples from the Bergell area. Data from horizontal (constant elevation) profiles indicate that no significant E-W tilting occurred after ~9 Ma and that the present day relief, especially in the valley where the Insubric/Tonale line is located, is at least 9 Ma old. Apatite (U-Th)/He age versus elevation data from a vertical transect in the core of the pluton suggests a three phases exhumation/cooling history: (1) fast exhumation/cooling until 16-12 Ma, (2) slow exhumation/cooling and (3) fast exhumation/cooling after ~6 Ma. Simulations of the apatite He ages versus elevation relationship, using a trial and error method, confirm these three exhumation/cooling phases. It furthermore suggests that the final exhumation stage initiated between 4 and 6 Ma ago, and continued at a relatively high rate until present time. By comparing this timing with the onset of major climatic, tectonic and base level drop events recognized in the Southern Alps, we propose that the Messinian base-level drop has initiated the late exhumation of the Bergell. However, as this event is relatively short (less than 1 Myr) it cannot explain the post 4 Ma-high exhumation rate. It is thus suggested that the transition to a more variable climate initiating at 3-4 Ma might have maintained high erosion

  9. Age determination of metal-poor halo stars using nucleochronometry

    NASA Astrophysics Data System (ADS)

    Christlieb, N.

    2016-09-01

    I describe the method of nucleochronometry for determining individual ages of stars, and report on results of the application of this method to old, metal-poor stars belonging to the Galactic halo population. I discuss uncertainties and caveats of this age determination method.

  10. Forensic odontology: age determination from adult human teeth.

    PubMed

    Lampe, H; Roetzscher, K

    1994-01-01

    Dentistry has several recognized specialities. Age, race and sex determination together with dental identification and facial reconstruction on skeletal material are procedures that the forensic odontologist has to master. The use of Gustafson's method to determine age in an examination of 350 teeth of living and/or dead males and females from the Heidelberg area, Germany is discussed. PMID:7772197

  11. Lead-alpha age determinations of granitic rocks from Alaska

    USGS Publications Warehouse

    Matzko, John J.; Jaffe, H.W.; Waring, C.L.

    1957-01-01

    Lead-alpha activity age determinations were made on zircon from seven granitic rocks of central and southeastern Alaska. The results of the age determinations indicate two periods of igneous intrusion, one about 95 million years ago, during the Cretaceous period, and another about 53 million years ago, during the early part of the Tertiary. The individual ages determined on zircon from 2 rocks from southeastern Alaska and 1 from east-central Alaska gave results of 90, 100, and 96 million years; those determined on 4 rocks from central Alaska gave results of 47, 56, 58, and 51 million years.

  12. Happiness and social determinants across age cohorts in Taiwan.

    PubMed

    Hsu, Hui-Chuan; Chang, Wen-Chiung; Chong, Young-Sook; An, Jeong Shin

    2016-09-01

    The purpose of this study was to examine happiness and social determinants across age cohorts in Taiwan. The data were obtained from the 2011 Taiwan Social Change Survey (aged 18 +, n = 2,199). The social determinants of happiness included socioeconomic status and social connection. Happiness was not different across the age groups. Receiving less family support, less formal support, more social trust and more control over life were significant for the younger group. Being married and having more social participation were significant for the middle-aged. Receiving less family support and having a higher economic status were significant for the older group.

  13. Developmental determinants in non-communicable chronic diseases and ageing.

    PubMed

    Bousquet, J; Anto, J M; Berkouk, K; Gergen, P; Antunes, J Pinto; Augé, P; Camuzat, T; Bringer, J; Mercier, J; Best, N; Bourret, R; Akdis, M; Arshad, S H; Bedbrook, A; Berr, C; Bush, A; Cavalli, G; Charles, M A; Clavel-Chapelon, F; Gillman, M; Gold, D R; Goldberg, M; Holloway, J W; Iozzo, P; Jacquemin, S; Jeandel, C; Kauffmann, F; Keil, T; Koppelman, G H; Krauss-Etschmann, S; Kuh, D; Lehmann, S; Carlsen, K C Lodrup; Maier, D; Méchali, M; Melén, E; Moatti, J P; Momas, I; Nérin, P; Postma, D S; Ritchie, K; Robine, J M; Samolinski, B; Siroux, V; Slagboom, P E; Smit, H A; Sunyer, J; Valenta, R; Van de Perre, P; Verdier, J M; Vrijheid, M; Wickman, M; Yiallouros, P; Zins, M

    2015-06-01

    Prenatal and peri-natal events play a fundamental role in health, development of diseases and ageing (Developmental Origins of Health and Disease (DOHaD)). Research on the determinants of active and healthy ageing is a priority to: (i) inform strategies for reducing societal and individual costs of an ageing population and (ii) develop effective novel prevention strategies. It is important to compare the trajectories of respiratory diseases with those of other chronic diseases.

  14. Tables for determining lead, uranium, and thorium isotope ages

    NASA Technical Reports Server (NTRS)

    Schonfeld, E.

    1974-01-01

    Tables for determining lead, uranium, and thorium isotope ages are presented in the form of computer printouts. Decay constants, analytical expressions for the functions evaluated, and the precision of the calculations are briefly discussed.

  15. Determining an age for the Inararo Tuff eruption of Mt. Pinatubo, based on correlation with a distal ash layer in core MD97-2142, South China Sea

    USGS Publications Warehouse

    Ku, Y.-P.; Chen, C.-H.; Newhall, C.G.; Song, S.-R.; Yang, T.F.; Iizuka, Y.; McGeehin, J.

    2008-01-01

    The largest known eruption of Mt. Pinatubo in the late Quaternary was the Inararo Tuff Formation (ITF) eruption, roughly estimated as five times larger than the 1991 eruption. The precise age of the ITF eruption has been uncertain. Here, a correlative of the ITF eruption, Layer D, is identified in marine sediments, and an age obtained. Tephras were identified in core MD97-2142 of Leg II of the IMAGES III cruise in northern offshore of Palawan, southeastern South China Sea (12??41.33???N, 119??27.90???E). On the basis of the geochemical and isotopic fingerprints, Layer D can be correlated with the ITF eruption of the modern Pinatubo-eruption sequence. By means of the MD97-2142 SPECMAP chronology, Layer D was dated at around 81??2 ka. This estimated age of the ITF eruption and tephra Layer D coincides with an anomalously high SO4-2 spike occurring within the 5 millennia from 79 to 84 ka in the GISP2 ice core record. ?? 2007.

  16. Age at first marriage in Nepal: differentials and determinants.

    PubMed

    Aryal, Tika Ram

    2007-09-01

    The aim of this paper is to investigate the differentials and determinants of female age at first marriage in rural Nepal. The life table technique was employed to calculate median age at marriage. The proportional hazard model was used to study the effect of various socioeconomic variables, and to identify the magnitude and significance of their effects on the timing of first marriage. The data were taken from a sample survey of Palpa and Rupandehi districts in rural Nepal. Both married and unmarried females of marriageable age were included in the survey. Median age at marriage was about 17 years for data from only married females, whereas it was about 18 years for data from married as well as unmarried females of marriageable age. Median age at marriage was about 16 years for uneducated females and 19 years for females educated up to intermediate or higher level. The analysis underestimates the median age at marriage for married females, probably due to right censoring. The risk of getting married early decreased gradually with increasing year-of-birth cohort. The risk of early marriage was higher among females of high socioeconomic status compared with those of low socioeconomic status. Females engaged in service married earlier than those engaged in household work. High socioeconomic status families are motivated, for religious and prestige reasons, to get their daughters married at an early age, preferably before menarche. Thus, education, occupation and age at menarche are the most powerful factors in deciding the timing of first marriage in Nepal.

  17. Determining Ages of APOGEE Giants with Known Distances

    NASA Astrophysics Data System (ADS)

    Feuillet, Diane K.; Bovy, Jo; Holtzman, Jon; Girardi, Léo; MacDonald, Nick; Majewski, Steven R.; Nidever, David L.

    2016-01-01

    We present a sample of 705 local giant stars observed using the New Mexico State University 1 m telescope with the Sloan Digital Sky Survey-III/Apache Point Observatory Galactic Evolution Experiment (APOGEE) spectrograph, for which we estimate stellar ages and the local star formation history (SFH). The high-resolution (R ˜ 22,500), near infrared (1.51-1.7 μm) APOGEE spectra provide measurements of stellar atmospheric parameters (temperature, surface gravity, [M/H], and [α/M]). Due to the smaller uncertainties in surface gravity possible with high-resolution spectra and accurate Hipparcos distance measurements, we are able to calculate the stellar masses to within 30%. For giants, the relatively rapid evolution up the red giant branch allows the age to be constrained by the mass. We examine methods of estimating age using both the mass-age relation directly and a Bayesian isochrone matching of measured parameters, assuming a constant SFH. To improve the SFH prior, we use a hierarchical modeling approach to constrain the parameters of the model SFH using the age probability distribution functions of the data. The results of an α-dependent Gaussian SFH model show a clear age-[α/M] relation at all ages. Using this SFH model as the prior for an empirical Bayesian analysis, we determine ages for individual stars. The resulting age-metallicity relation is flat, with a slight decrease in [M/H] at the oldest ages and a ˜0.5 dex spread in metallicity across most ages. For stars with ages ≲1 Gyr we find a smaller spread, consistent with radial migration having a smaller effect on these young stars than on the older stars.

  18. Juvenile (age 13-18) smoking incidence determinants in Greece.

    PubMed

    Vasilopoulos, Aristidis; Gourgoulianis, Konstantinos; Hatzoglou, Chryssi; Roupa, Zoe

    2015-10-01

    Smoking is a form of medical addiction, usually adopted during adolescence. The aim was to determine the prevalence of smoking in adolescents, aged 13-18 years old, to investigate their attitudes towards smoking and determine the contribution of social influences to onset and continuation of smoking. An anonymous self-report questionnaire was filled in by 873 high school students of Central Greece. Smoking incidence was 19.2%, with a 13.7% of regular smokers. The presence of a smoker in the family and a smoker friend were correlated with increased smoking rates. School grades were correlated negatively with smoking attitude and positively with allowance. Age was correlated negatively with social influence. Social influence appears stronger on younger ages and is a main determinant of smoking behavior. A more susceptible attitude towards smoking is formed during late adolescence. Certain social predictive factors for attitude towards smoking are proposed. PMID:24628676

  19. Postnatal Foot Length to Determine Gestational Age: A Pilot Study.

    PubMed

    Wyk, Lizelle Van; Smith, Johan

    2016-04-01

    Gestational age is a critical factor in the management, decision-making, prognostication and follow-up of newborn infants. It is also essential for research and epidemiology. In the absence of an early assessment of fetal gestation by abdominal ultrasound, many neonatal units in developing countries determine gestational age by neonatal scores and last menstrual period-both of which are highly inaccurate. The aim of this pilot study was to determine whether postnatal foot length measurement could accurately determine gestational age in a specified South African hospitalized neonatal population. Foot length was measured with a plastic Verniere's caliper. Foot length was shown to correlate well with gestational age (r = 0.919,p < 0.001). Intra-observer and inter-observer variability of foot length measurements was low. Foot length can therefore be used with high accuracy to determine the gestational age in a population where there is poor access to or utilization of antenatal sonar. PMID:26758249

  20. Postnatal Foot Length to Determine Gestational Age: A Pilot Study.

    PubMed

    Wyk, Lizelle Van; Smith, Johan

    2016-04-01

    Gestational age is a critical factor in the management, decision-making, prognostication and follow-up of newborn infants. It is also essential for research and epidemiology. In the absence of an early assessment of fetal gestation by abdominal ultrasound, many neonatal units in developing countries determine gestational age by neonatal scores and last menstrual period-both of which are highly inaccurate. The aim of this pilot study was to determine whether postnatal foot length measurement could accurately determine gestational age in a specified South African hospitalized neonatal population. Foot length was measured with a plastic Verniere's caliper. Foot length was shown to correlate well with gestational age (r = 0.919,p < 0.001). Intra-observer and inter-observer variability of foot length measurements was low. Foot length can therefore be used with high accuracy to determine the gestational age in a population where there is poor access to or utilization of antenatal sonar.

  1. Spectroscopic Determination of Masses (and Implied Ages) for Red Giants

    NASA Astrophysics Data System (ADS)

    Ness, M.; Hogg, David W.; Rix, H.-W.; Martig, M.; Pinsonneault, Marc H.; Ho, A. Y. Q.

    2016-06-01

    The mass of a star is arguably its most fundamental parameter. For red giant stars, tracers luminous enough to be observed across the Galaxy, mass implies a stellar evolution age. It has proven to be extremely difficult to infer ages and masses directly from red giant spectra using existing methods. From the Kepler and apogee surveys, samples of several thousand stars exist with high-quality spectra and asteroseismic masses. Here we show that from these data we can build a data-driven spectral model using The Cannon, which can determine stellar masses to ˜0.07 dex from apogee dr12 spectra of red giants; these imply age estimates accurate to ˜0.2 dex (40%). We show that The Cannon constrains these ages foremost from spectral regions with CN absorption lines, elements whose surface abundances reflect mass-dependent dredge-up. We deliver an unprecedented catalog of 70,000 giants (including 20,000 red clump stars) with mass and age estimates, spanning the entire disk (from the Galactic center to R˜ 20 kpc). We show that the age information in the spectra is not simply a corollary of the birth-material abundances {{[Fe/H]}} and [α /{Fe}], and that, even within a monoabundance population of stars, there are age variations that vary sensibly with Galactic position. Such stellar age constraints across the Milky Way open up new avenues in Galactic archeology.

  2. Spectroscopic determination of masses (and implied ages) for red giants

    NASA Astrophysics Data System (ADS)

    Ness, Melissa; Hogg, David W.; Rix, Hans-Walter; Martig, Marie; Ho, Anna

    2016-01-01

    The mass of a star is arguably its most fundamental parameter and for red giant stars it implies a stellar evolution age. Stellar masses and ages have never been derived directly from spectra of red giants. However, using the APOGEE Kepler sample of stars, (the APOKASC sample), with high-quality spectra and astroseismic masses, we can build a data-driven spectral model using THE CANNON (arXiv:1501.07604) to infer stellar mass and therefore age from stellar spectra. We determine stellar masses to 0.07 dex from APOGEE DR12 spectra of red giants; these imply age estimates accurate to 0.2 dex (40 percent). THE CANNON constrains the ages foremost from spectral regions with particular absorption lines, elements whose surface abundances reflect mass-dependent dredge-up. We deliver an unprecedented catalog of 85,000 giants (including 20,000 red-clump stars) with mass and age estimates, spanning the entire disk (from the Galactic center to R ˜ 20 kpc). Such stellar age constraints across the Milky Way open up new avenues in Galactic archeology.

  3. Age determination of 15 old to intermediate-age small Magellanic cloud star clusters

    SciTech Connect

    Parisi, M. C.; Clariá, J. J.; Piatti, A. E.; Geisler, D.; Leiton, R.; Carraro, G.; Costa, E.; Grocholski, A. J.; Sarajedini, A. E-mail: claria@oac.uncor.edu E-mail: dgeisler@astro-udec.cl E-mail: gcarraro@eso.org E-mail: grocholski@phys.lsu.edu

    2014-04-01

    We present color-magnitude diagrams in the V and I bands for 15 star clusters in the Small Magellanic Cloud (SMC) based on data taken with the Very Large Telescope (VLT, Chile). We selected these clusters from our previous work, wherein we derived cluster radial velocities and metallicities from calcium II infrared triplet (CaT) spectra also taken with the VLT. We discovered that the ages of six of our clusters have been appreciably underestimated by previous studies, which used comparatively small telescopes, graphically illustrating the need for large apertures to obtain reliable ages of old and intermediate-age SMC star clusters. In particular, three of these clusters, L4, L6, and L110, turn out to be among the oldest SMC clusters known, with ages of 7.9 ± 1.1, 8.7 ± 1.2, and 7.6 ± 1.0 Gyr, respectively, helping to fill a possible 'SMC cluster age gap'. Using the current ages and metallicities from Parisi et al., we analyze the age distribution, age gradient, and age-metallicity relation (AMR) of a sample of SMC clusters measured homogeneously. There is a suggestion of bimodality in the age distribution but it does not show a constant slope for the first 4 Gyr, and we find no evidence for an age gradient. Due to the improved ages of our cluster sample, we find that our AMR is now better represented in the intermediate/old period than we had derived in Parisi et al., where we simply took ages available in the literature. Additionally, clusters younger than ∼4 Gyr now show better agreement with the bursting model of Pagel and Tautvaišienė, but we confirm that this model is not a good representation of the AMR during the intermediate/old period. A more complicated model is needed to explain the SMC chemical evolution in that period.

  4. Pteridine fluorescence for age determination of Anopheles mosquitoes.

    PubMed

    Wu, D; Lehane, M J

    1999-02-01

    The age structure of mosquito populations is of great relevance to understanding the dynamics of disease transmission and in monitoring the success of control operations. Unfortunately, the ovarian dissection methods currently available for determining the age of adult mosquitoes are technically difficult, slow and may be of limited value, because the proportion of diagnostic ovarioles in the ovary declines with age. By means of reversed-phase HPLC this study investigated the malaria vectors Anopheles gambiae and An. stephensi to see if changes in fluorescent pteridine pigments, which have been used in other insects to determine the age of field-caught individuals, may be useful for age determination in mosquitoes. Whole body fluorescence was inversely proportional to age (P < 0.001, r2 > 91%) up to 30 days postemergence, with the regression values: y = 40580-706x for An. gambiae, and y = 52896-681x for An. stephensi. In both species the main pteridines were 6-biopterin, pterin-6-carboxylic acid and an unidentified fluorescent compound. An. gambiae had only 50-70% as much fluorescence as An. stephensi, and fluorescent compounds were relatively more concentrated in the head than in the thorax (ratios 1:0.8 An. gambiae; 1:0.5 An. stephensi). The results of this laboratory study are encouraging. It seems feasible that this simpler and faster technique of fluorescence quantification could yield results of equivalent accuracy to the interpretation of ovarian dissection. A double-blind field trial comparing the accuracy of this technique to marked, released and recaptured mosquitoes is required to test the usefulness of the pteridine method in the field. PMID:10194749

  5. Age determination of single plutonium particles after chemical separation

    NASA Astrophysics Data System (ADS)

    Shinonaga, T.; Donohue, D.; Ciurapinski, A.; Klose, D.

    2009-01-01

    Age determination of single plutonium particles was demonstrated using five particles of the standard reference material, NBS 947 (Plutonium Isotopic Standard. National Bureau of Standards, Washington, D.C. 20234, August 19, 1982, currently distributed as NBL CRM-137) and the radioactive decay of 241Pu into 241Am. The elemental ratio of Am/Pu in Pu particles found on a carbon planchet was measured by wavelength dispersive X-ray spectrometry (WDX) coupled to a scanning electron microscope (SEM). After the WDX measurement, each plutonium particle, with an average size of a few μm, was picked up and relocated to a silicon wafer inside the SEM chamber using a micromanipulator. The silicon wafer was then transferred to a quartz tube for dissolution in an acid solution prior to chemical separation. After the Pu was chemically separated from Am and U, the isotopic ratios of Pu ( 240Pu/ 239Pu, 241Pu/ 239Pu and 242Pu/ 239Pu) were measured with a thermal ionization mass spectrometer (TIMS) for the calculation of Pu age. The age of particles determined in this study was in good agreement with the expected age (35.9 a) of NBS 947 within the measurement uncertainty.

  6. Age of sex-determining mechanisms in vertebrates.

    PubMed

    WITSCHI, E

    1959-08-14

    Certain characteristic patterns of physiologic sex determination are not causally linked with types of genic and chromosomal constitution (XX-XY or ZW-ZZ). The observed widespread but not universal parallelism in the distribution of genetic and physiologic patterns among vertebrate groups expresses genealogic relationship. On the basis of this interpretation one may estimate the approximate evolutionary age of the mechanism of genetic sex determination. It is concluded that in all tetrapod vertebrates these mechanisms originated during the Jurassic period. Environmental conditions seem to affect the progress of this evolution. PMID:13675759

  7. Age of sex-determining mechanisms in vertebrates.

    PubMed

    WITSCHI, E

    1959-08-14

    Certain characteristic patterns of physiologic sex determination are not causally linked with types of genic and chromosomal constitution (XX-XY or ZW-ZZ). The observed widespread but not universal parallelism in the distribution of genetic and physiologic patterns among vertebrate groups expresses genealogic relationship. On the basis of this interpretation one may estimate the approximate evolutionary age of the mechanism of genetic sex determination. It is concluded that in all tetrapod vertebrates these mechanisms originated during the Jurassic period. Environmental conditions seem to affect the progress of this evolution.

  8. 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

  9. DNA Damage: A Main Determinant of Vascular Aging

    PubMed Central

    Bautista-Niño, Paula K.; Portilla-Fernandez, Eliana; Vaughan, Douglas E.; Danser, A. H. Jan; Roks, Anton J. M.

    2016-01-01

    Vascular aging plays a central role in health problems and mortality in older people. Apart from the impact of several classical cardiovascular risk factors on the vasculature, chronological aging remains the single most important determinant of cardiovascular problems. The causative mechanisms by which chronological aging mediates its impact, independently from classical risk factors, remain to be elucidated. In recent years evidence has accumulated that unrepaired DNA damage may play an important role. Observations in animal models and in humans indicate that under conditions during which DNA damage accumulates in an accelerated rate, functional decline of the vasculature takes place in a similar but more rapid or more exaggerated way than occurs in the absence of such conditions. Also epidemiological studies suggest a relationship between DNA maintenance and age-related cardiovascular disease. Accordingly, mouse models of defective DNA repair are means to study the mechanisms involved in biological aging of the vasculature. We here review the evidence of the role of DNA damage in vascular aging, and present mechanisms by which genomic instability interferes with regulation of the vascular tone. In addition, we present potential remedies against vascular aging induced by genomic instability. Central to this review is the role of diverse types of DNA damage (telomeric, non-telomeric and mitochondrial), of cellular changes (apoptosis, senescence, autophagy), mediators of senescence and cell growth (plasminogen activator inhibitor-1 (PAI-1), cyclin-dependent kinase inhibitors, senescence-associated secretory phenotype (SASP)/senescence-messaging secretome (SMS), insulin and insulin-like growth factor 1 (IGF-1) signaling), the adenosine monophosphate-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR)-nuclear factor kappa B (NFκB) axis, reactive oxygen species (ROS) vs. endothelial nitric oxide synthase (eNOS)-cyclic guanosine monophosphate (c

  10. Icy Satellites of Saturn: Impact Cratering and Age Determination

    NASA Technical Reports Server (NTRS)

    Dones, L.; Chapman, C. R.; McKinnon, William B.; Melosh, H. J.; Kirchoff, M. R.; Neukum, G.; Zahnle, K. J.

    2009-01-01

    Saturn is the first giant planet to be visited by an orbiting spacecraft that can transmit large amounts of data to Earth. Crater counts on satellites from Phoebe inward to the regular satellites and ring moons are providing unprecedented insights into the origin and time histories of the impacting populations. Many Voyager-era scientists concluded that the satellites had been struck by at least two populations of impactors. In this view, the Population I impactors, which were generally judged to be comets orbiting the Sun, formed most of the larger and older craters, while Population II impactors, interpreted as Saturn-orbiting ejecta from impacts on satellites, produced most of the smaller and younger craters. Voyager data also implied that all of the ring moons, and probably some of the midsized classical moons, had been catastrophically disrupted and reaccreted since they formed. We examine models of the primary impactor populations in the Saturn system. At the present time, ecliptic comets, which likely originate in the Kuiper belt/scattered disk, are predicted to dominate impacts on the regular satellites and ring moons, but the models require extrapolations in size (from the observed Kuiper belt objects to the much smaller bodies that produce the craters) or in distance (from the known active Jupiter family comets to 9.5 AU). Phoebe, Iapetus, and perhaps even moons closer to Saturn have been struck by irregular satellites as well. We describe the Nice model, which provides a plausible mechanism by which the entire Solar System might have experienced an era of heavy bombardment long after the planets formed. We then discuss the three cratering chronologies, including one based upon the Nice model, that have been used to infer surface ages from crater densities on the saturnian satellites. After reviewing scaling relations between the properties of impactors and the craters they produce, we provide model estimates of the present-day rate at which comets impact

  11. Determining the Ages of Nearby A-Stars with Long-Baseline Interferometry

    NASA Astrophysics Data System (ADS)

    Jones, Jeremy; White, R. J.; Boyajian, T.; Schaefer, G.; Baines, E.; Ireland, M.; Patience, J.; Aff001

    2016-01-01

    We determine the age of 7 stars in the Ursa Major moving group using a novel method that models the fundamental parameters of rapidly rotating A-stars based on interferometric observations and literature photometry and compares these parameters (namely, radius, luminosity, and rotation velocity) with evolution models that account for rotation. We find these stars to be coeval, thus providing an age estimate for the moving group and validating this technique. With this technique validated, we determine the age of the rapidly rotating, directly imaged planet host star, κ Andromedae.

  12. Distribution and determinants of functioning and disability in aged adults - results from the German KORA-Age study

    PubMed Central

    2013-01-01

    Background Today industrialized countries face a burgeoning aged population. Thus, there is increasing attention on the functioning and disabilities of aged adults as potential determinants of autonomy and independent living. However, there are few representative findings on the prevalence and determinants of disability in aged persons in the German population. The objective of our study is to examine the frequency, distribution and determinants of functioning and disability in aged persons and to assess the contribution of diseases to the prevalence of disability. Methods Data originate from the MONICA/KORA study, a population-based epidemiological cohort. Survivors of the original cohorts who were 65 and older were examined by telephone interview in 2009. Disability was assessed with the Health Assessment Questionnaire Disability Index (HAQ-DI). Minimal disability was defined as HAQ-DI > 0. Logistic regression was used to adjust for potential confounders and additive regression to estimate the contribution of diseases to disability prevalence. Results We analyzed a total of 4117 persons (51.2% female) with a mean age of 73.6 years (SD = 6.1). Minimal disability was present in 44.7% of all participants. Adjusted for age and diseases, disability was positively associated with female sex, BMI, low income, marital status, physical inactivity and poor nutritional status, but not with smoking and education. Problems with joint functions and eye diseases contributed most to disability prevalence in all age groups. Conclusions In conclusion, this study could show that there are vulnerable subgroups of aged adults who should receive increased attention, specifically women, those with low income, those over 80, and persons with joint or eye diseases. Physical activity, obesity and malnutrition were identified as modifiable factors for future targeted interventions. PMID:23410010

  13. Effect of age-based and environment-based cues on reproductive investment in Gambusia affinis

    PubMed Central

    Billman, Eric J; Belk, Mark C

    2014-01-01

    We examined the multivariate life-history trajectories of age 0 and age 1 female Gambusia affinis to determine relative effects of age-based and environment-based cues on reproductive investment. Age 0 females decreased reproductive investment prior to the onset of fall and winter months, while age 1 females increased reproductive investment as the summer progressed. The reproductive restraint and terminal investment patterns exhibited by age 0 and age 1 females, respectively, were consistent with the predictions from the cost of reproduction hypothesis. Age 0 females responded to environment-based cues, decreasing reproductive investment to increase the probability of overwinter survival and subsequent reproductive opportunities in the following summer. Age 1 females responded to age-based cues, or the proximity of death, increasing investment to current reproduction as future reproductive opportunities decreased late in life. Thus, individuals use multiple cues to determine the level of reproductive investment, and the response to each cue is dependent on the age of an individual. PMID:24967079

  14. Metabolic reserve as a determinant of cognitive aging.

    PubMed

    Stranahan, Alexis M; Mattson, Mark P

    2012-01-01

    Mild cognitive impairment (MCI) and Alzheimer's disease (AD) represent points on a continuum of cognitive performance in aged populations. Cognition may be impaired or preserved in the context of brain aging. One theory to account for memory maintenance in the context of extensive pathology involves 'cognitive reserve', or the ability to compensate for neuropathology through greater recruitment of remaining neurons. In this review, we propose a complementary hypothesis of 'metabolic reserve', where a brain with high metabolic reserve is characterized by the presence of neuronal circuits that respond adaptively to perturbations in cellular and somatic energy metabolism and thereby protects against declining cognition. Lifestyle determinants of metabolic reserve, such as exercise, reduced caloric intake, and intake of specific dietary components can promote neuroprotection, while pathological states arising from sedentary lifestyles and excessive caloric intake contribute to neuronal endangerment. This bidirectional relationship between metabolism and cognition may be mediated by alterations in central insulin and neurotrophic factor signaling and glucose metabolism, with downstream consequences for accumulation of amyloid-β and hyperphosphorylated tau. The metabolic reserve hypothesis is supported by epidemiological findings and the spectrum of individual cognitive trajectories during aging, with additional data from animal models identifying potential mechanisms for this relationship. Identification of biomarkers for metabolic reserve could assist in generating a predictive model for the likelihood of cognitive decline with aging. PMID:22045480

  15. [Determination of gestational age by sonar (author's transl)].

    PubMed

    Hinselmann, M

    1976-10-01

    For some time it has been recognized that abnormal intrauterine development can lead to dissociation between maturity and external size and/or weight of the fetus. The results of pathophysiological and biochemical studies of fetal growth and nutrition have resulted in attempts to monitor and time every pregnancy at risk. The most recent information in the area of intrauterine development has shown that also organic and functional maturity of fetal organ systems can develop dissociated from gestational age. This observation points out the necessity for additional measures in order to achieve the goals of Planed obstetrics. The possibilities of ultrasound biometry for determining gestational age were presented. Taking normal and abnormal fetal growth and behavior into consideration, the use of ultrasonic diagnostic methods makes it possible to acquire concrete data regarding the size and maturity of some fetal organ systems. The methodological problems such as arise in clinical practice were explained and discussed in light of the most recent developments in equipment.

  16. Age of an Indonesian Fossil Tooth Determined by Electron Paramagnetic Resonance

    SciTech Connect

    Bogard, JS

    2004-04-07

    The first fossil hominid tooth recovered during 1999 excavations from the Cisanca River region in West Java, Indonesia, was associated with a series of bovid teeth from a single individual that was recovered 190 cm beneath the hominid tooth. The age of the fossil bovid teeth was determined using electron paramagnetic resonance (EPR) analysis as part of an effort to bracket the age of the hominid tooth. The EPR-derived age of the bovid teeth is (5.16 {+-} 2.01) x 10{sup 5} years. However, the age estimate reported here is likely an underestimate of the actual age of deposition since evidence of heating was detected in the EPR spectra of the bovid teeth, and the heating may have caused a decrease in the intensity of EPR components on which the age calculation is based.

  17. Content-based image retrieval applied to bone age assessment

    NASA Astrophysics Data System (ADS)

    Fischer, Benedikt; Brosig, André; Welter, Petra; Grouls, Christoph; Günther, Rolf W.; Deserno, Thomas M.

    2010-03-01

    Radiological bone age assessment is based on local image regions of interest (ROI), such as the epiphysis or the area of carpal bones. These are compared to a standardized reference and scores determining the skeletal maturity are calculated. For computer-aided diagnosis, automatic ROI extraction and analysis is done so far mainly by heuristic approaches. Due to high variations in the imaged biological material and differences in age, gender and ethnic origin, automatic analysis is difficult and frequently requires manual interactions. On the contrary, epiphyseal regions (eROIs) can be compared to previous cases with known age by content-based image retrieval (CBIR). This requires a sufficient number of cases with reliable positioning of the eROI centers. In this first approach to bone age assessment by CBIR, we conduct leaving-oneout experiments on 1,102 left hand radiographs and 15,428 metacarpal and phalangeal eROIs from the USC hand atlas. The similarity of the eROIs is assessed by cross-correlation of 16x16 scaled eROIs. The effects of the number of eROIs, two age computation methods as well as the number of considered CBIR references are analyzed. The best results yield an error rate of 1.16 years and a standard deviation of 0.85 years. As the appearance of the hand varies naturally by up to two years, these results clearly demonstrate the applicability of the CBIR approach for bone age estimation.

  18. Assessment of nutritional status: effects of different methods to determine age on the classification of undernutrition.

    PubMed

    Gorstein, J

    1989-01-01

    The evaluation of nutritional status using anthropometry has been widely employed in field studies and nutritional surveillance programmes. Two of the primary indicators used, weight-for-age and height-for-age, require accurate age information for proper assessments to be made. Three data sets on nutritional status were evaluated using different methods to determine age: rounding to the most recently attained month, rounding to the nearest whole month, and ages computed from birth dates and visit dates. The impact of these different methods on the classification of nutritional status were found to be dramatic, especially in infants during the first year of life. In some cases, when ages are rounded to the most recently attained month, as few as 43% of the children classified as malnourished based on the indicator, height-for-age, and the cut-off point, less than -2 Standard Deviations from the reference median, are identified relative to when ages are computed from birth and visit dates. Beyond the discrepancies in estimating prevalence below specific cut-off points to designate undernutrition, the use of the different methods also affects entire distributions. The problem of using different methods to estimate age, and the impact they have on the classification of undernutrition are of critical public health importance, especially when this information is used to identify individuals and groups as well as for planning and policy development.

  19. Lifestyle and dietary factors determine age at natural menopause.

    PubMed

    Sapre, Shilpa; Thakur, Ratna

    2014-01-01

    A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to identify the modifiable risk factors like diet and lifestyle changes. Delayed menopause is associated with increased risk of endometrial and breast cancer, while early ANM enhances the risk for cardiovascular diseases and osteoporosis. The correlation between diet and ANM has not been extensively studied; however, whatever studies have been done till now point towards role of high intake of total calories, fruits, and proteins in delaying the ANM, while high polyunsaturated fat intake accelerates it. The role of dietary soy, total fat, saturated fat, red meat, and dietary fiber in determining the ANM has been controversial and needs further studies to substantiate it. The lifestyle factors like current smoking and vigorous exercise have been significantly associated with early menopause, while moderate alcohol consumption delays the ANM. Large prospective studies are needed to study the association of ANM and other modifiable factors like passive smoking fish consumption, soy, and various types of tea. The knowledge of modifiable determinants of ANM can help in setting up menopausal clinics and initiating health programs specially in developing countries.

  20. Lifestyle and dietary factors determine age at natural menopause.

    PubMed

    Sapre, Shilpa; Thakur, Ratna

    2014-01-01

    A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to identify the modifiable risk factors like diet and lifestyle changes. Delayed menopause is associated with increased risk of endometrial and breast cancer, while early ANM enhances the risk for cardiovascular diseases and osteoporosis. The correlation between diet and ANM has not been extensively studied; however, whatever studies have been done till now point towards role of high intake of total calories, fruits, and proteins in delaying the ANM, while high polyunsaturated fat intake accelerates it. The role of dietary soy, total fat, saturated fat, red meat, and dietary fiber in determining the ANM has been controversial and needs further studies to substantiate it. The lifestyle factors like current smoking and vigorous exercise have been significantly associated with early menopause, while moderate alcohol consumption delays the ANM. Large prospective studies are needed to study the association of ANM and other modifiable factors like passive smoking fish consumption, soy, and various types of tea. The knowledge of modifiable determinants of ANM can help in setting up menopausal clinics and initiating health programs specially in developing countries. PMID:24672198

  1. Determining the Average Age of School Plant Building Space.

    ERIC Educational Resources Information Center

    Uerling, Donald F.

    1984-01-01

    Presents a method for calculating the age of the space in a specific building inventory, and suggests some practical applications. A fourfold procedure is provided for finding the average age of total building space. (TE)

  2. Age-based discrimination of rival males in western bluebirds.

    PubMed

    Akçay, Çağlar; Arnold, J Andrew; Hambury, Katherine L; Dickinson, Janis L

    2016-09-01

    Adaptive social behavior frequently involves discriminating between classes of individuals such as relatives versus non-relatives, older versus younger individuals, or individuals of different status. In the absence of spatial cues, this discrimination may be based on signals that correlate with fitness-related traits (e.g., older or high-status males may sing higher performance songs) or with identity, for example, when receivers distinguish and classify signalers based on their unique signal structure. Here, we examine vocal age-based discrimination in western bluebirds (Sialia mexicana), a North American songbird in which older males have a significant advantage in obtaining extra-pair fertilizations, and therefore pose a significantly higher threat to paternity than younger males. We asked whether western bluebird males showed a higher response to playback of songs of older males compared to younger males relative to their own age. We prepared song stimuli by removing three potential signals of age that have been identified as important in other species: (1) note consistency (which was achieved by playing a single instance of each note repeatedly), (2) note repertoire size, and (3) singing rate (the latter two were equalized across conditions). Even in the absence of these potential signals of age, young males responded more strongly to playback of older males' songs than to young males' songs, suggesting that they are able to discriminate between age classes relative to the threat they pose. Further research is required to determine whether this discrimination is based on individual recognition or signal features that are correlated with age. PMID:27271774

  3. Determining the age of cats by pulp cavity/tooth width ratio using dental radiography

    PubMed Central

    Park, Kyoungsun; Ahn, Jaesang; Kang, Sunmee; Lee, Euiri; Kim, Soohyun; Park, Sangwan; Park, Sungwon; Noh, Hyunwoo

    2014-01-01

    The purpose of this study was to evaluate the effect of age on the ratio of pulp cavity/tooth width (P/T ratio) in healthy cats. The dental radiographs of 32 cats (16 males and 16 females) were generated with a digital dental X-ray unit with the animals under general anesthesia. Standardized measurement of the canine teeth was performed by drawing a line on the radiograph perpendicular to the cementoenamel junction (CEJ) of the tooth. There was an inversely proportional correlation between chronological age and the P/T ratio. Moreover, a strong Pearson squared correlation (γ2 = 0.92) was identified by the curved regression model. No significant differences in the P/T ratio based on gender or breed were found. These results suggest that determination of age by P/T ratio could be clinically useful for estimating the chronological age of cats. PMID:25234207

  4. Determining the age of cats by pulp cavity/tooth width ratio using dental radiography.

    PubMed

    Park, Kyoungsun; Ahn, Jaesang; Kang, Sunmee; Lee, Euiri; Kim, Soohyun; Park, Sangwan; Park, Sungwon; Noh, Hyunwoo; Seo, Kangmoon

    2014-12-01

    The purpose of this study was to evaluate the effect of age on the ratio of pulp cavity/tooth width (P/T ratio) in healthy cats. The dental radiographs of 32 cats (16 males and 16 females) were generated with a digital dental X-ray unit with the animals under general anesthesia. Standardized measurement of the canine teeth was performed by drawing a line on the radiograph perpendicular to the cemento- enamel junction (CEJ) of the tooth. There was an inversely proportional correlation between chronological age and the P/T ratio. Moreover, a strong Pearson squared correlation (γ(2) = 0.92) was identified by the curved regression model. No significant differences in the P/T ratio based on gender or breed were found. These results suggest that determination of age by P/T ratio could be clinically useful for estimating the chronological age of cats. PMID:25234207

  5. Volatile constituents of Melissa officinalis leaves determined by plant age.

    PubMed

    Nurzyńska-Wierdak, Renata; Bogucka-Kocka, Anna; Szymczak, Grazyna

    2014-05-01

    The present study investigated changes in the content and chemical composition of the essential oil extracted by hydrodistillation from air-dried Melissa officinalis L. (lemon balm) leaves in the first and second year of plant growth. The lemon balm oil was analysed by GC-MS and GC-FID. The presence of 106 compounds, representing 100% of the oil constituents, was determined in the oil. The predominant components were geranial (45.2% and 45.1%) and neral (32.8% and 33.8%); their proportions in the examined samples of the oil obtained from one- and two-year-old plants were comparable. However, the age of lemon balm plants affected the concentration of other constituents and the proportions of the following compounds were subject to especially high fluctuations: citronellal (8.7% and 0.4%), geraniol (trace amounts and 0.6%), and geranyl acetate (0.5% and 3.0%), as well as, among others, isogeranial, E-caryophyllene, caryophyllene oxide, germacrene D, and carvacrol. The essential oil of two-year-old plants was characterized by a richer chemical composition than the oil from younger plants. PMID:25026727

  6. Nongenetic Determinants of Age at Menarche: A Systematic Review

    PubMed Central

    2014-01-01

    Background. The acceleration of pubertal development is an important medical and social problem, as it may result in increased morbidity and mortality in later life. This systematic review summarizes relevant data about nongenetic factors, which contribute to age at menarche (AAM), and suggests those which may be the most important. Methods. The available literature from 1980 till July 2013 was searched using PubMed and Google Scholar databases. Finally, 154 papers were selected for the analysis. Results. Environmental factors, which may affect AAM, vary in populations of different ethnicity. The prenatal, infancy, and early childhood periods are the most susceptible to these factors. Body weight, high animal protein intake, family stressors (e.g., single parenting), and physical activity seem to influence AAM in most populations. Conclusions. The data about influence of nongenetic factors on AAM are still inconsistent. The factors affecting prenatal and early childhood growth seem to have a larger effect on further sexual maturation. Further studies are needed in order to validate the association between other environmental determinants and AAM in different ethnical groups. PMID:25050345

  7. Volatile constituents of Melissa officinalis leaves determined by plant age.

    PubMed

    Nurzyńska-Wierdak, Renata; Bogucka-Kocka, Anna; Szymczak, Grazyna

    2014-05-01

    The present study investigated changes in the content and chemical composition of the essential oil extracted by hydrodistillation from air-dried Melissa officinalis L. (lemon balm) leaves in the first and second year of plant growth. The lemon balm oil was analysed by GC-MS and GC-FID. The presence of 106 compounds, representing 100% of the oil constituents, was determined in the oil. The predominant components were geranial (45.2% and 45.1%) and neral (32.8% and 33.8%); their proportions in the examined samples of the oil obtained from one- and two-year-old plants were comparable. However, the age of lemon balm plants affected the concentration of other constituents and the proportions of the following compounds were subject to especially high fluctuations: citronellal (8.7% and 0.4%), geraniol (trace amounts and 0.6%), and geranyl acetate (0.5% and 3.0%), as well as, among others, isogeranial, E-caryophyllene, caryophyllene oxide, germacrene D, and carvacrol. The essential oil of two-year-old plants was characterized by a richer chemical composition than the oil from younger plants.

  8. Determinants of undernutrition among children aged 6 to 59 months in rural Zambézia Province, Mozambique: Results of two population-based serial cross-sectional surveys

    PubMed Central

    Rose, Elizabeth S.; Blevins, Meridith; González-Calvo, Lazaro; Ndatimana, Elisée; Green, Ann F.; Lopez, Melanie; Olupona, Omo; Vermund, Sten H.; Moon, Troy D.

    2016-01-01

    Background While many countries are transitioning from epidemics of undernutrition to overnutrition, Mozambique’s very high 44% prevalence of stunting in children under age 5 years is cause for serious concern. Methods We conducted two population-based cross-sectional surveys of ~4000 female heads of households each in Zambézia Province, Mozambique from August–September 2010 (Baseline) and April–May 2014 (Endline) as part of the USAID funded Strengthening Communities through Integrated Programs (SCIP) grant. Anthropometric measurements were collected on 560 children aged 6–59 months at Baseline and 912 children at Endline and classified as: “stunted,” a height-for-age z-score less than -2; “wasted,” weight-for-height z-score less than -2; and “underweight,” weight-for-age z-score less than -2. Descriptive statistics and logistic regression using Stata 13.1 were used to examine factors associated with undernutrition. Results Of children under age five years, 43% were undernourished in 2010 and 55% in 2014. The most common form of undernutrition was stunting (39% in 2010, 51% in 2014), followed by underweight (13% in both 2010 and 2014), and wasting (7% in 2010, 5% in 2014). Child’s age was found to have a non-linear association with stunting. Vitamin A supplementation was associated with a 31% (p=0.04) decreased odds of stunting. Children who were exclusively breastfed for at least six months had an 80% (p=0.02) lower odds of wasting in 2014 and 57% (p=0.05) decreased odds of being underweight in 2014. Introducing other foods after age six months was associated with a five-fold increased odds of wasting in 2014 (p=0.02); household food insecurity was associated with wasting (OR=2.08; p=0.03) and underweight in 2010 (OR=2.31; p=0.05). Children whose mother washed her hands with a cleaning agent had a 40% (p=0.05) decreased odds of being underweight. Surprisingly, per point increase in household dietary diversity score, children had 12% greater

  9. Determination of Appropriate Weight-Based Cutoffs for Empiric Cefazolin Dosing Using Data from a Phase 1 Pharmacokinetics and Safety Study of Cefazolin Administered for Surgical Prophylaxis in Pediatric Patients Aged 10 to 12 Years

    PubMed Central

    Schmitz, Michael L.; Blumer, Jeffrey L.; Cetnarowski, Wes

    2015-01-01

    Despite over 40 years of worldwide usage, relatively few data have been published on the pharmacokinetics of cefazolin in pediatric surgical patients. The primary objectives of this study were to examine the pharmacokinetics and safety of cefazolin in children 10 to 12 years of age (inclusive) receiving 1 or 2 g of cefazolin, based on body weight. This multiple-center, open-label study enrolled pediatric patients electively scheduled for surgical procedures who required cefazolin as part of their routine clinical management. Patients weighing ≥25 to <50 kg received a 1-g dose, and patients weighing ≥50 to ≤85 kg received a 2-g dose. Postdose pharmacokinetic and safety assessments were conducted following drug administration. Cefazolin concentration-time data were analyzed by using both noncompartmental and population pharmacokinetics methods. Monte Carlo simulations were performed to identify appropriate weight-based cutoffs for the dosing of children aged 10 to 17 years of age. Twelve patients were enrolled in this study and provided the requisite pharmacokinetic data. In general, cefazolin was well tolerated. The mean cefazolin terminal elimination half-life, clearance, and area under the concentration-time curve from time zero to infinity in this population were 1.95 h, 0.804 ml/min/kg, and 607 mg · h/liter, respectively. Patients weighing 50 to 60 kg exhibited elevated cefazolin exposures. Observed pharmacokinetic parameters and simulation results indicated that a weight-based cutoff of 60 kg is predicted to provide cefazolin exposure consistent with that observed in normal, healthy adults at recommended doses for surgical prophylaxis. (This study has been registered at ClinicalTrials.gov under registration no. NCT01904357.) PMID:25941220

  10. The problem of age determination in living individuals

    NASA Astrophysics Data System (ADS)

    Andrade, Marina A. P.; Cardoso, Hugo F. V.

    2013-10-01

    The increase of international illegal emigration has raise the need for forensic age estimation of foreigners without valid identification documents. In this work the discussion is about some methods to estimate age in humans, with the emphasis on their importance and constrains. Some preliminary results and a brief statistical discussion, concerning its accuracy, are performed.

  11. Aging is a weak but relentless determinant of dementia severity

    PubMed Central

    Royall, Donald R.; Palmer, Raymond F.

    2016-01-01

    Structural Equation Models (SEM) can explicitly distinguish “dementia-relevant” variance in cognitive task performance (i.e., “δ” for dementia). In prior work, δ appears to uniquely account for dementia severity regardless of the cognitive measures used to construct it. In this study, we test δ as a mediator of age's prospective association with future cognitive performance and dementia severity in a large, ethnically diverse longitudinal cohort, the Texas Alzheimer's Research and Care Consortium (TARCC). Age had adverse effects on future cognition, and these were largely mediated through δ, independently of education, ethnicity, gender, depression ratings, serum homo-cysteine levels, hemoglobin A1c, and apolipoprotein e4 status. Age explained 4% of variance in δ, and through it, 11-18% of variance in future cognitive performance. Our findings suggest that normative aging is a dementing condition (i.e., a “senility”). While the majority of variance in dementia severity must be independent of age, age's specific effect is likely to accumulate over the lifespan. Our findings also constrain age's dementing effects on cognition to the age-related fraction of “general intelligence” (Spearman's “g”). That has broad biological and pathophysiological implications. PMID:26930722

  12. 38 CFR 3.208 - Claims based on attained age.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... age. 3.208 Section 3.208 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Claims based on attained age. In claims for pension where the age of the veteran or surviving spouse is material, the statements of age will be accepted where they are in agreement with other statements in...

  13. 38 CFR 3.208 - Claims based on attained age.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... age. 3.208 Section 3.208 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Claims based on attained age. In claims for pension where the age of the veteran or surviving spouse is material, the statements of age will be accepted where they are in agreement with other statements in...

  14. 38 CFR 3.208 - Claims based on attained age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... age. 3.208 Section 3.208 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Claims based on attained age. In claims for pension where the age of the veteran or surviving spouse is material, the statements of age will be accepted where they are in agreement with other statements in...

  15. 38 CFR 3.208 - Claims based on attained age.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... age. 3.208 Section 3.208 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Claims based on attained age. In claims for pension where the age of the veteran or surviving spouse is material, the statements of age will be accepted where they are in agreement with other statements in...

  16. 38 CFR 3.208 - Claims based on attained age.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... age. 3.208 Section 3.208 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS... Claims based on attained age. In claims for pension where the age of the veteran or surviving spouse is material, the statements of age will be accepted where they are in agreement with other statements in...

  17. [Hard to accurately determine the age of children seeking asylum].

    PubMed

    Hjern, Anders; Ascher, Henry

    2015-01-01

    Many unaccompanied asylum seeking young people in Europe lack documents proving their age. X rays of the wrist and wisdom teeth are often used by European migration authorities to assess age in this situation. The large inter-individual differences in physical maturation during adolescence create such large margins of error for these methods that their informative value is very limited. The Swedish National Board of Health and Welfare should reconsider its previous position on these methods and examine the possibility to include psychosocial methods in these age assessment procedures. PMID:26461513

  18. BioAge: Toward A Multi-Determined, Mechanistic Account of Cognitive Aging

    PubMed Central

    DeCarlo, Correne A.; Tuokko, Holly A.; Williams, Dorothy; Dixon, Roger A.; MacDonald, Stuart W.S.

    2014-01-01

    The search for reliable early indicators of age-related cognitive decline represents a critical avenue for progress in aging research. Chronological age is a commonly used developmental index; however, it offers little insight into the mechanisms underlying cognitive decline. In contrast, biological age (BioAge), reflecting the vitality of essential biological systems, represents a promising operationalization of developmental time. Current BioAge models have successfully predicted age-related cognitive deficits. Research on aging-related cognitive function indicates that the interaction of multiple risk and protective factors across the human lifespan confers individual risk for late-life cognitive decline, implicating a multi-causal explanation. In this review, we explore current BioAge models, describe three broad yet pathologically relevant biological processes linked to cognitive decline, and propose a novel operationalization of BioAge accounting for both moderating and causal mechanisms of cognitive decline and dementia. We argue that a multivariate and mechanistic BioAge approach will lead to a greater understanding of disease pathology as well as more accurate prediction and early identification of late-life cognitive decline. PMID:25278166

  19. Age as a determinant of reproductive success among captive female rhesus macaques (Macaca mulatta).

    PubMed

    Gagliardi, Christine; Liukkonen, John R; Phillippi-Falkenstein, Kathrine M; Harrison, Richard M; Kubisch, H Michael

    2007-04-01

    A retrospective analysis was performed on fertility outcomes among a colony of captive Indian rhesus monkeys. The analysis covered over 30 years and was based on 1443 females with a total of 11,453 pregnancies. Various determinants of fertility were assessed including birth rates, pregnancy loss, infant survival, interbirth intervals, and interval from last birth to death. Binary variables were analyzed with generalized linear models with random intercepts, while linear mixed models were used for analysis of continuous variables. Age of the dam was a significant factor in determining whether a pregnancy resulted in a birth and whether an infant survived the first 30 days with primiparous or older mothers being less likely to produce an infant surviving to that age. In contrast, sex proved to be the only significant factor in determining whether an infant lived to 1 year, with females being more likely to survive. The interval between births proved to be affected primarily by dam age, while the late death of an infant depressed the likelihood of an extended time interval between her last birth and her death. Overall, these results demonstrate that maternal age contributes significantly to a decline in fertility and older females can live relatively long periods following birth of their last infant. PMID:17504925

  20. 5 CFR 1650.31 - Age-based withdrawals.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 3 2014-01-01 2014-01-01 false Age-based withdrawals. 1650.31 Section... FUNDS FROM THE THRIFT SAVINGS PLAN In-Service Withdrawals § 1650.31 Age-based withdrawals. (a) A participant who has reached age 591/2 and who has not separated from Government service is eligible...

  1. 5 CFR 1650.31 - Age-based withdrawals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Age-based withdrawals. 1650.31 Section... FUNDS FROM THE THRIFT SAVINGS PLAN In-Service Withdrawals § 1650.31 Age-based withdrawals. (a) A participant who has reached age 591/2 and who has not separated from Government employment is eligible...

  2. 5 CFR 1650.31 - Age-based withdrawals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Age-based withdrawals. 1650.31 Section... FUNDS FROM THE THRIFT SAVINGS PLAN In-Service Withdrawals § 1650.31 Age-based withdrawals. (a) A participant who has reached age 591/2 and who has not separated from Government employment is eligible...

  3. 5 CFR 1650.31 - Age-based withdrawals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Age-based withdrawals. 1650.31 Section... FUNDS FROM THE THRIFT SAVINGS PLAN In-Service Withdrawals § 1650.31 Age-based withdrawals. (a) A participant who has reached age 591/2 and who has not separated from Government employment is eligible...

  4. 5 CFR 1650.31 - Age-based withdrawals.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Age-based withdrawals. 1650.31 Section... FUNDS FROM THE THRIFT SAVINGS PLAN In-Service Withdrawals § 1650.31 Age-based withdrawals. (a) A participant who has reached age 591/2 and who has not separated from Government service is eligible...

  5. Aging related changes in determinants of muscle force generating capacity: a comparison of muscle aging in men and male rodents.

    PubMed

    Ballak, Sam B; Degens, Hans; de Haan, Arnold; Jaspers, Richard T

    2014-03-01

    Human aging is associated with a progressive decline in skeletal muscle mass and force generating capacity, however the exact mechanisms underlying these changes are not fully understood. Rodents models have often been used to enhance our understanding of mechanisms of age-related changes in human skeletal muscle. However, to what extent age-related alterations in determinants of muscle force generating capacity observed in rodents resemble those in humans has not been considered thoroughly. This review compares the effect of aging on muscle force generating determinants (muscle mass, fiber size, fiber number, fiber type distribution and muscle specific tension), in men and male rodents at similar relative age. It appears that muscle aging in male F344*BN rat resembles that in men most; 32-35-month-old rats exhibit similar signs of muscle weakness to those of 70-80-yr-old men, and the decline in 36-38-month-old rats is similar to that in men aged over 80 yrs. For male C57BL/6 mice, age-related decline in muscle force generating capacity seems to occur only at higher relative age than in men. We conclude that the effects on determinants of muscle force differ between species as well as within species, but qualitatively show the same pattern as that observed in men.

  6. Reciprocal Changes in Phosphoenolpyruvate Carboxykinase and Pyruvate Kinase with Age Are a Determinant of Aging in Caenorhabditis elegans.

    PubMed

    Yuan, Yiyuan; Hakimi, Parvin; Kao, Clara; Kao, Allison; Liu, Ruifu; Janocha, Allison; Boyd-Tressler, Andrea; Hang, Xi; Alhoraibi, Hanna; Slater, Erin; Xia, Kevin; Cao, Pengxiu; Shue, Quinn; Ching, Tsui-Ting; Hsu, Ao-Lin; Erzurum, Serpil C; Dubyak, George R; Berger, Nathan A; Hanson, Richard W; Feng, Zhaoyang

    2016-01-15

    Aging involves progressive loss of cellular function and integrity, presumably caused by accumulated stochastic damage to cells. Alterations in energy metabolism contribute to aging, but how energy metabolism changes with age, how these changes affect aging, and whether they can be modified to modulate aging remain unclear. In locomotory muscle of post-fertile Caenorhabditis elegans, we identified a progressive decrease in cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C), a longevity-associated metabolic enzyme, and a reciprocal increase in glycolytic pyruvate kinase (PK) that were necessary and sufficient to limit lifespan. Decline in PEPCK-C with age also led to loss of cellular function and integrity including muscle activity, and cellular senescence. Genetic and pharmacologic interventions of PEPCK-C, muscle activity, and AMPK signaling demonstrate that declines in PEPCK-C and muscle function with age interacted to limit reproductive life and lifespan via disrupted energy homeostasis. Quantifications of metabolic flux show that reciprocal changes in PEPCK-C and PK with age shunted energy metabolism toward glycolysis, reducing mitochondrial bioenergetics. Last, calorie restriction countered changes in PEPCK-C and PK with age to elicit anti-aging effects via TOR inhibition. Thus, a programmed metabolic event involving PEPCK-C and PK is a determinant of aging that can be modified to modulate aging.

  7. Reciprocal Changes in Phosphoenolpyruvate Carboxykinase and Pyruvate Kinase with Age Are a Determinant of Aging in Caenorhabditis elegans.

    PubMed

    Yuan, Yiyuan; Hakimi, Parvin; Kao, Clara; Kao, Allison; Liu, Ruifu; Janocha, Allison; Boyd-Tressler, Andrea; Hang, Xi; Alhoraibi, Hanna; Slater, Erin; Xia, Kevin; Cao, Pengxiu; Shue, Quinn; Ching, Tsui-Ting; Hsu, Ao-Lin; Erzurum, Serpil C; Dubyak, George R; Berger, Nathan A; Hanson, Richard W; Feng, Zhaoyang

    2016-01-15

    Aging involves progressive loss of cellular function and integrity, presumably caused by accumulated stochastic damage to cells. Alterations in energy metabolism contribute to aging, but how energy metabolism changes with age, how these changes affect aging, and whether they can be modified to modulate aging remain unclear. In locomotory muscle of post-fertile Caenorhabditis elegans, we identified a progressive decrease in cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C), a longevity-associated metabolic enzyme, and a reciprocal increase in glycolytic pyruvate kinase (PK) that were necessary and sufficient to limit lifespan. Decline in PEPCK-C with age also led to loss of cellular function and integrity including muscle activity, and cellular senescence. Genetic and pharmacologic interventions of PEPCK-C, muscle activity, and AMPK signaling demonstrate that declines in PEPCK-C and muscle function with age interacted to limit reproductive life and lifespan via disrupted energy homeostasis. Quantifications of metabolic flux show that reciprocal changes in PEPCK-C and PK with age shunted energy metabolism toward glycolysis, reducing mitochondrial bioenergetics. Last, calorie restriction countered changes in PEPCK-C and PK with age to elicit anti-aging effects via TOR inhibition. Thus, a programmed metabolic event involving PEPCK-C and PK is a determinant of aging that can be modified to modulate aging. PMID:26631730

  8. 77 FR 4858 - Culturally Significant Objects Imported for Exhibition Determinations: “Byzantium and Islam: Age...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-31

    ... Culturally Significant Objects Imported for Exhibition Determinations: ``Byzantium and Islam: Age of... determinations made by ] the Department of State pertaining to the exhibition ``Byzantium and Islam: Age of... Islam: Age of Transition (7th-9th Century),'' imported from abroad for temporary exhibition within...

  9. 29 CFR Appendix D to Part 4044 - Tables Used To Determine Expected Retirement Age

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 9 2013-07-01 2013-07-01 false Tables Used To Determine Expected Retirement Age D Appendix... 4044—Tables Used To Determine Expected Retirement Age Table I-13—Selection of Retirement Rate Category... II-B. 3 Table II-C. Table II-A—Expected Retirement Ages for Individuals in the Low...

  10. 29 CFR Appendix D to Part 4044 - Tables Used To Determine Expected Retirement Age

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Tables Used To Determine Expected Retirement Age D Appendix... 4044—Tables Used To Determine Expected Retirement Age TABLE I-10—Selection of Retirement Rate Category... II-B. 3 Table II-C. Table II-A—Expected Retirement Ages for Individuals in the Low...

  11. 29 CFR Appendix D to Part 4044 - Tables Used To Determine Expected Retirement Age

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 9 2012-07-01 2012-07-01 false Tables Used To Determine Expected Retirement Age D Appendix... 4044—Tables Used To Determine Expected Retirement Age Table I-12— Selection of Retirement Rate Category... II-B. 3 Table II-C. Table II-A—Expected Retirement Ages for Individuals in the Low...

  12. 29 CFR Appendix D to Part 4044 - Tables Used To Determine Expected Retirement Age

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 9 2014-07-01 2014-07-01 false Tables Used To Determine Expected Retirement Age D Appendix... 4044—Tables Used To Determine Expected Retirement Age Table I-14—Selection of Retirement Rate Category... II-B. 3 Table II-C. Table II-A—Expected Retirement Ages for Individuals in the Low...

  13. Age and sex determination of juvenile band-tailed pigeons

    USGS Publications Warehouse

    White, J.A.; Braun, C.E.

    1978-01-01

    Captive band-tailed pigeons (Columbafasciata) were studied to document progression of molts and plumages from juvenal to adult age. Immature pigeons began the post-juvenal molt at 35 days which continued up to 340 days. The only 3 plumage characters useful for identification and estimation of age were presence of juvenal lesser, middle, and greater secondary coverts, juvenal secondaries, and juvenal primaries. While juvenal primaries were still present, hatching dates could be estimated up to 252 days (N = 84). Secondary feather presence and molt stage could be used to identify juvenile pigeons for more than 340 days (N = 24). Using coloration of the crown and breast feathers, 96 percent of the immature pigeons examined (106 of 110) at 80 days of age were classified accurately as to sex.

  14. Age determination of late Pleistocene marine transgression in western Alaska

    USGS Publications Warehouse

    Szabo, B. J.

    1982-01-01

    Dating molluscs from sediments representing the Kotzebuan marine transgression in Alaska yields an average uranium-series age of 104,000 ?? 22,000 yrs B.P. This and other selected Pleistocene marine deposits of western Alaska are tentatively correlated with radiometrically dated units of eastern Baffin Island, Arctic Canada. ?? 1982.

  15. [Significance of the ear in the determination of age].

    PubMed

    Röhm, E; Adam, E

    1986-01-01

    The morphology of human ear conch is said to be rather individual, but a perfect person-identification by this mean is not possible. It is demonstrated by photographs-made in a 15 years' interval-that ear conch and auricular area can be typically marked by proceeding age and specific diseases.

  16. [Significance of the ear in the determination of age].

    PubMed

    Röhm, E; Adam, E

    1986-01-01

    The morphology of human ear conch is said to be rather individual, but a perfect person-identification by this mean is not possible. It is demonstrated by photographs-made in a 15 years' interval-that ear conch and auricular area can be typically marked by proceeding age and specific diseases. PMID:3741048

  17. Healthy Aging Promotion through Neuroscientific Information-Based Strategies.

    PubMed

    Seinfeld, Sofia; Sanchez-Vives, Maria V

    2015-10-01

    To ensure the well-being of a rapidly growing elderly population, it is fundamental to find strategies to foster healthy brain aging. With this intention, we designed a program of scientific-based lectures aimed at dissemination by established neuroscientists about brain function, brain plasticity and how lifestyle influences the brain. We also carried out a pilot study on the impact of the lectures on attendees. The objective was to provide information to elderly people in order to encourage them to identify unhealthy and healthy daily habits, and more importantly, to promote behavioral changes towards healthy brain aging. Here we report on our experience. In order to determine the impact of the lectures in the daily routine of the attendees, we asked them to fill out questionnaires. Preliminary results indicate that neuroscientific information-based strategies can be a useful method to have a positive impact on the lives of elderly, increase their awareness on how to improve brain function and promote positive lifestyle modifications. Furthermore, based on self-reported data, we also found that through this strategy it is possible to promote behavioral changes related to nutrition, sleep, and realization of physical and cognitively stimulating activities. Finally, based on the results obtained, the importance of promoting self-efficacy and the empowerment of the older populations is highlighted. PMID:26426029

  18. Healthy Aging Promotion through Neuroscientific Information-Based Strategies

    PubMed Central

    Seinfeld, Sofia; Sanchez-Vives, Maria V.

    2015-01-01

    To ensure the well-being of a rapidly growing elderly population, it is fundamental to find strategies to foster healthy brain aging. With this intention, we designed a program of scientific-based lectures aimed at dissemination by established neuroscientists about brain function, brain plasticity and how lifestyle influences the brain. We also carried out a pilot study on the impact of the lectures on attendees. The objective was to provide information to elderly people in order to encourage them to identify unhealthy and healthy daily habits, and more importantly, to promote behavioral changes towards healthy brain aging. Here we report on our experience. In order to determine the impact of the lectures in the daily routine of the attendees, we asked them to fill out questionnaires. Preliminary results indicate that neuroscientific information-based strategies can be a useful method to have a positive impact on the lives of elderly, increase their awareness on how to improve brain function and promote positive lifestyle modifications. Furthermore, based on self-reported data, we also found that through this strategy it is possible to promote behavioral changes related to nutrition, sleep, and realization of physical and cognitively stimulating activities. Finally, based on the results obtained, the importance of promoting self-efficacy and the empowerment of the older populations is highlighted. PMID:26426029

  19. Healthy Aging Promotion through Neuroscientific Information-Based Strategies.

    PubMed

    Seinfeld, Sofia; Sanchez-Vives, Maria V

    2015-09-28

    To ensure the well-being of a rapidly growing elderly population, it is fundamental to find strategies to foster healthy brain aging. With this intention, we designed a program of scientific-based lectures aimed at dissemination by established neuroscientists about brain function, brain plasticity and how lifestyle influences the brain. We also carried out a pilot study on the impact of the lectures on attendees. The objective was to provide information to elderly people in order to encourage them to identify unhealthy and healthy daily habits, and more importantly, to promote behavioral changes towards healthy brain aging. Here we report on our experience. In order to determine the impact of the lectures in the daily routine of the attendees, we asked them to fill out questionnaires. Preliminary results indicate that neuroscientific information-based strategies can be a useful method to have a positive impact on the lives of elderly, increase their awareness on how to improve brain function and promote positive lifestyle modifications. Furthermore, based on self-reported data, we also found that through this strategy it is possible to promote behavioral changes related to nutrition, sleep, and realization of physical and cognitively stimulating activities. Finally, based on the results obtained, the importance of promoting self-efficacy and the empowerment of the older populations is highlighted.

  20. The Future of Age-Based Public Policy.

    ERIC Educational Resources Information Center

    Hudson, Robert B.; And Others

    1995-01-01

    This issue deals with the future of an age-based public policy. Articles discuss the history of age-based public policy; the competing bases for benefits; population dynamics; Social Security, Medicaid, and Medicare; employer policies; and local and state policies. Describes California's Linkages Program. (JOW)

  1. The Age of the Directly Imaged Planet Host Star κ Andromedae Determined from Interferometric Observations

    NASA Astrophysics Data System (ADS)

    Jones, Jeremy; White, R. J.; Quinn, S.; Ireland, M.; Boyajian, T.; Schaefer, G.; Baines, E. K.

    2016-05-01

    κ Andromedae, an early-type star that hosts a directly imaged low-mass companion, is expected to be oblate due to its rapid rotational velocity (v sin i = ˜162 km s‑1). We observed the star with the CHARA Array’s optical beam combiner, PAVO, measuring its size at multiple orientations and determining its oblateness. The interferometric measurements, combined with photometry and this v sin i value are used to constrain an oblate star model that yields the fundamental properties of the star and finds a rotation speed that is ˜85% of the critical rate and a low inclination of ˜30°. Three modeled properties (the average radius, bolometric luminosity, and equatorial velocity) are compared to MESA evolution models to determine an age and mass for the star. In doing so, we determine an age for the system of {47}-40+27 Myr. Based on this age and previous measurements of the companion’s temperature, the BHAC15 evolution models imply a mass for the companion of {22}-9+8 M J.

  2. Determinants of birthweight: gender based analysis.

    PubMed

    Halileh, Samia; Abu-Rmeileh, Niveen; Watt, Graham; Spencer, Nick; Gordon, Nahida

    2008-09-01

    The objective of this cross sectional study is to look at determinants of birth weight and their association with the gender of the baby in 2,795 full term children living in the occupied Palestinian territory, derived from a stratified random sample of 2,994 households in the West Bank and 2,234 households in the Gaza Strip. The response rate was 85%. Multivariable analysis using analysis of variance for mixed models showed that sex and birth order, maternal age and education and to a lesser extent region were determinants of birth weight for all children. The effect of maternal education on birth weight differed for female and male infants, tending to be relatively unchanged for male infants and with mean birth weights increasing with maternal education in female infants. The effect of birth order differed by maternal age, with mean birth weight increasing with maternal age for first and second births; but being unaffected by maternal age for infants of birth order greater than two. We conclude that birth weight is influenced by common biological determinants across cultures, but is also influenced by social, ethnic, and environmental factors that are culture specific, of which some might be gender related. PMID:18463972

  3. Evaluation of the Applicability of Different Age Determination Methods for Estimating Age of the Endangered African Wild Dog (Lycaon Pictus)

    PubMed Central

    Steenkamp, Gerhard; Groom, Rosemary J.

    2016-01-01

    African wild dogs (Lycaon pictus) are endangered and their population continues to decline throughout their range. Given their conservation status, more research focused on their population dynamics, population growth and age specific mortality is needed and this requires reliable estimates of age and age of mortality. Various age determination methods from teeth and skull measurements have been applied in numerous studies and it is fundamental to test the validity of these methods and their applicability to different species. In this study we assessed the accuracy of estimating chronological age and age class of African wild dogs, from dental age measured by (i) counting cementum annuli (ii) pulp cavity/tooth width ratio, (iii) tooth wear (measured by tooth crown height) (iv) tooth wear (measured by tooth crown width/crown height ratio) (v) tooth weight and (vi) skull measurements (length, width and height). A sample of 29 African wild dog skulls, from opportunistically located carcasses was analysed. Linear and ordinal regression analysis was done to investigate the performance of each of the six age determination methods in predicting wild dog chronological age and age class. Counting cementum annuli was the most accurate method for estimating chronological age of wild dogs with a 79% predictive capacity, while pulp cavity/tooth width ratio was also a reliable method with a 68% predictive capacity. Counting cementum annuli and pulp cavity/tooth width ratio were again the most accurate methods for separating wild dogs into three age classes (6–24 months; 25–60 months and > 60 months), with a McFadden’s Pseudo-R2 of 0.705 and 0.412 respectively. The use of the cementum annuli method is recommended when estimating age of wild dogs since it is the most reliable method. However, its use is limited as it requires tooth extraction and shipping, is time consuming and expensive, and is not applicable to living individuals. Pulp cavity/tooth width ratio is a

  4. Gender difference in health and its determinants in the old-aged population in India.

    PubMed

    Dhak, Biplab

    2009-09-01

    This paper examines the gender differential in health and its socioeconomic and demographic determinants in the old-age population of India based on the National Sample Survey 60th round data collected in 2004. As in developed countries, older women in India report poorer self-reported health and experience greater immobility compared with men. Stepwise logistic regression analysis shows that the gender differential in health is linked to various socioeconomic and demographic variables and that the gender gap could be narrowed with appropriate policy intervention. Specifically, paying special attention towards improving the socioeconomic status of widowed/separated women could attenuate a substantial portion of the observed gender gap in the health of the old-age population. PMID:19563694

  5. Higher Education and the Determination of Aggregate Male Employment by Age

    ERIC Educational Resources Information Center

    Stenberg, Anders; Wikstrom, Magnus

    2004-01-01

    This paper studies the determinants of age-specific employment rates among Swedish males, focusing on the effect of education on employment. We use cohort specific data for the time period 1984-1996 covering male cohorts aged 21-45. It is found that aggregate age-group-specific employment rates increase with the proportion of the cohort with an…

  6. Towards an evidence-based model of aging.

    PubMed

    Katcher, Harold L

    2015-01-01

    The modern synthesis or evolutionary theory of aging assumes that aging results from the accumulation of errors or damages at the cellular level through the inadequacies of an organism's repair and maintenance machinery. The demonstration of cellular and organic rejuvenation requires the hypothesis that aging is the result of irreparable damage to be rejected. I will propose basic principles of mammalian aging based only on experimental data, without imposing the constraints of evolutionary theory. Consideration of the results of experiment suggests that fundamental assumptions about cell and organ aging being autonomous process, and about the centrality of cellular aging in organismic aging are wrong. The derived principles indicate that exogenous control of age-phenotype at cellular and higher levels of biological organization is possible. PMID:26054348

  7. A Complication in Determining the Precise Age of the Solar System

    NASA Astrophysics Data System (ADS)

    Brennecka, G. A.

    2010-01-01

    Primitive components in meteorites contain a detailed record of the conditions and processes in the solar nebula, the cloud of dust and gas surrounding the infant Sun. Determining accurately when the first materials formed requires the lead-lead (Pb-Pb) dating method, a method based on the decay of uranium (U) isotopes to Pb isotopes. The initial ratio of U-238 to U-235 is critical to determining the ages correctly, and many studies have concluded that the ratio is constant for any given age. However, my colleagues at Arizona State University, Institut fur Geowissenschaften, Goethe-Universitat (Frankfurt, Germany), and the Senckenberg Forschungsinstitut und Naturmuseum (also in Frankfurt) and I have found that some calcium-aluminum-rich inclusions (CAIs) in chondritic meteorites deviate from the conventional value for the U-238/U-235 ratio. This could lead to inaccuracies of up to 5 million years in the age of these objects, if no correction is made. Variations in the concentrations of thorium and neodymium with the U-238/U-235 ratio suggest that the ratio may have been lowered by the decay of curium-247, which decays to U-235 with a half-life of 15.6 million years. Curium-247 is created in certain types of energetic supernovae, so its presence suggests that a supernova added material to the pre-solar interstellar cloud between 110 and 140 million years before the Solar System began to form.

  8. Age-related energy values of bakery meal for broiler chickens determined using the regression method.

    PubMed

    Stefanello, C; Vieira, S L; Xue, P; Ajuwon, K M; Adeola, O

    2016-07-01

    A study was conducted to determine the ileal digestible energy (IDE), ME, and MEn contents of bakery meal using the regression method and to evaluate whether the energy values are age-dependent in broiler chickens from zero to 21 d post hatching. Seven hundred and eighty male Ross 708 chicks were fed 3 experimental diets in which bakery meal was incorporated into a corn-soybean meal-based reference diet at zero, 100, or 200 g/kg by replacing the energy-yielding ingredients. A 3 × 3 factorial arrangement of 3 ages (1, 2, or 3 wk) and 3 dietary bakery meal levels were used. Birds were fed the same experimental diets in these 3 evaluated ages. Birds were grouped by weight into 10 replicates per treatment in a randomized complete block design. Apparent ileal digestibility and total tract retention of DM, N, and energy were calculated. Expression of mucin (MUC2), sodium-dependent phosphate transporter (NaPi-IIb), solute carrier family 7 (cationic amino acid transporter, Y(+) system, SLC7A2), glucose (GLUT2), and sodium-glucose linked transporter (SGLT1) genes were measured at each age in the jejunum by real-time PCR. Addition of bakery meal to the reference diet resulted in a linear decrease in retention of DM, N, and energy, and a quadratic reduction (P < 0.05) in N retention and ME. There was a linear increase in DM, N, and energy as birds' ages increased from 1 to 3 wk. Dietary bakery meal did not affect jejunal gene expression. Expression of genes encoding MUC2, NaPi-IIb, and SLC7A2 linearly increased (P < 0.05) with age. Regression-derived MEn of bakery meal linearly increased (P < 0.05) as the age of birds increased, with values of 2,710, 2,820, and 2,923 kcal/kg DM for 1, 2, and 3 wk, respectively. Based on these results, utilization of energy and nitrogen in the basal diet decreased when bakery meal was included and increased with age of broiler chickens.

  9. Age- and Gender-Based Populations

    MedlinePlus

    ... societal benefits of prevention, treatment, and recovery for mental and substance use disorders. Popular Programs, Campaigns, & Initiatives National Registry of Evidence-based Programs and Practices (NREPP) Medication-Assisted Treatment (MAT) Too Smart To ...

  10. Geo-structural mapping and age determinations of Rembrandt basin.

    NASA Astrophysics Data System (ADS)

    Ferrari, Sabrina; Massironi, Matteo; Martellato, Elena; Giacomini, Lorenza; Cremonese, Gabriele; Rothery, David; Prockter, Louise M.

    During its second and thirds flybys MESSENGER imaged a new large and well-preserved basin called Rembrandt Basin (Watters et al., 2009) in Mercury's southern hemisphere. Rembrandt is partially filled by volcanic overlay and is crossed by a marked lobate scarp with some similarities to another prominent mercurian lobate scarp, Beagle Rupes. In attempt to reveal Rembrandt Basin evolution, we mapped its geological units inferring -where possible -their stratigraphic relationships. In addition, we performed crater counts on several of these units and derived age estimates by applying Model Production Function (MPF) absolute-model chronology (Marchi et al., 2009). Since Rembrandt basin (in contrast to other well-seen basins) displays evidence of global-scale in addition to basin-localized deformation (Watters et al. 2009), it is characterized by different tectonic features that in some cases may be controlled by rheological layering within the crust. We attempted to map the contractional and extensional local patterns and the global tectonic features. Notably, the pronounced scarp transecting a 60 km crater near the edge of Rembrandt's inner ring and other structural features in the surrounding regions suggest a linked fault system. The apparent bow shape of this feature could be compared with Beagle Rupes, and similarly may imply special conditions of weakness inside the crust (Rothery and Massironi, 2010). Ref. Watters, T. R., Head, J. W., Solomon, S. C., Robinson, M. S., Chapman, C. R., Denevi, B. W., Fassett, C. I., Murchie, S. L., and Strom, R. G., 2009. Evolution of the Rembrandt Impact Basin on Mercury. Science, 324 , 618-621. Marchi, S., Mottola, S., Cremonese, G., Massironi, M., and Martellato, E., 2009. A new Chronology for the Moon and Mercury. Astronomical Journal, 137 , 4936-4948. Rothery, D. A. and Massironi, M., 2010. Beagle Rupes -evidence for a basal decollement of regional extent in Mercury's lithosphere. Icarus (In Press).

  11. Age estimation based on Kvaal's technique using digital panoramic radiographs

    PubMed Central

    Mittal, Samta; Nagendrareddy, Suma Gundareddy; Sharma, Manisha Lakhanpal; Agnihotri, Poornapragna; Chaudhary, Sunil; Dhillon, Manu

    2016-01-01

    Introduction: Age estimation is important for administrative and ethical reasons and also because of legal consequences. Dental pulp undergoes regression in size with increasing age due to secondary dentin deposition and can be used as a parameter of age estimation even beyond 25 years of age. Kvaal et al. developed a method for chronological age estimation based on the pulp size using periapical dental radiographs. There is a need for testing this method of age estimation in the Indian population using simple tools like digital imaging on living individuals not requiring extraction of teeth. Aims and Objectives: Estimation of the chronological age of subjects by Kvaal's method using digital panoramic radiographs and also testing the validity of regression equations as given by Kvaal et al. Materials and Methods: The study sample included a total of 152 subjects in the age group of 14-60 years. Measurements were performed on the standardized digital panoramic radiographs based on Kvaal's method. Different regression formulae were derived and the age was assessed. The assessed age was then correlated to the actual age of the patient using Student's t-test. Results: No significant difference between the mean of the chronological age and the estimated age was observed. However, the values of the mean age estimated by using regression equations as given previously in the study of Kvaal et al. significantly underestimated the chronological age in the present study sample. Conclusion: The results of the study give an inference for the feasibility of this technique by calculation of regression equations on digital panoramic radiographs. However, it negates the applicability of same regression equations as given by Kvaal et al. on the study population. PMID:27555738

  12. Simultaneous determination of sugars and organic acids in aged vinegars and chemometric data analysis.

    PubMed

    Cocchi, M; Durante, C; Grandi, M; Lambertini, P; Manzini, D; Marchetti, A

    2006-07-15

    Aceto Balsamico Tradizionale of Modena (ABTM) is a typical product (PDO denomination) of the province of Modena produced by cooked grape must which undergoes a long ageing period (at least 12 years) in series of wooden casks (batterie). The study of the transformations of this product during ageing is extremely relevant in order to control the authenticity of ABTM towards succedaneous products and mislabelling of age. This paper presents the results of the investigation of sugars and fixed organic acids in ABTM samples of different ages, coming from different batterie. The analytes were simultaneously determined by a gas chromatographic method optimised for this peculiar matrix. The method shows good separation and resolution of the investigated chemical species and allows their determination in the concentration ranges reported in brackets: malic (7.6-15.5 g kg(-1)), tartaric (4.0-9.7 g kg(-1)), citric (0.6-1.5 g kg(-1)) and succinic (0.36-0.62 g kg(-1)) acid and glucose (153-294 g kg(-1)), fructose (131-279 g kg(-1)), xylose (011-0.39 g kg(-1)), ribose (0.078-0.429 g kg(-1)), rhamnose (0.061-0.195 g kg(-1)), galactose (0.136-0.388 g kg(-1)), mannose (0.41-1.46 g kg(-1)), arabinose (0.33-1.00 g kg(-1)) and sucrose (0.46-6.84 g kg(-1)), with mean associated errors ranging from 5 to 19% depending on the analytes. Moreover, the recovery values are always satisfactory, being close to one for most of the analytes. Furthermore, in order to assess the degree of variability of the different analytes content with vinegar ageing and the similarity/dissimilarity among series of casks a three-way data analysis method (Tucker3) is proposed. The chemometric technique applied on the data set shows differences between the samples on the bases of their different ageing period, and between the batterie, which traditionally have an own peculiar production procedure.

  13. Absolute ages from crater statistics: Using radiometric ages of Martian samples for determining the Martian cratering chronology

    NASA Technical Reports Server (NTRS)

    Neukum, G.

    1988-01-01

    In the absence of dates derived from rock samples, impact crater frequencies are commonly used to date Martian surface units. All models for absolute dating rely on the lunar cratering chronology and on the validity of its extrapolation to Martian conditions. Starting from somewhat different lunar chronologies, rather different Martian cratering chronologies are found in the literature. Currently favored models are compared. The differences at old ages are significant, the differences at younger ages are considerable and give absolute ages for the same crater frequencies as different as a factor of 3. The total uncertainty could be much higher, though, since the ratio of lunar to Martian cratering rate which is of basic importance in the models is believed to be known no better than within a factor of 2. Thus, it is of crucial importance for understanding the the evolution of Mars and determining the sequence of events to establish an unambiguous Martian cratering chronology from crater statistics in combination with clean radiometric ages of returned Martian samples. For the dating goal, rocks should be as pristine as possible from a geologically simple area with a one-stage emplacement history of the local formation. A minimum of at least one highland site for old ages, two intermediate-aged sites, and one very young site is needed.

  14. Age and distraction are determinants of performance on a novel visual search task in aged Beagle dogs.

    PubMed

    Snigdha, Shikha; Christie, Lori-Ann; De Rivera, Christina; Araujo, Joseph A; Milgram, Norton W; Cotman, Carl W

    2012-02-01

    Aging has been shown to disrupt performance on tasks that require intact visual search and discrimination abilities in human studies. The goal of the present study was to determine if canines show age-related decline in their ability to perform a novel simultaneous visual search task. Three groups of canines were included: a young group (N = 10; 3 to 4.5 years), an old group (N = 10; 8 to 9.5 years), and a senior group (N = 8; 11 to 15.3 years). Subjects were first tested for their ability to learn a simple two-choice discrimination task, followed by the visual search task. Attentional demands in the task were manipulated by varying the number of distracter items; dogs received an equal number of trials with either zero, one, two, or three distracters. Performance on the two-choice discrimination task varied with age, with senior canines making significantly more errors than the young. Performance accuracy on the visual search task also varied with age; senior animals were significantly impaired compared to both the young and old, and old canines were intermediate in performance between young and senior. Accuracy decreased significantly with added distracters in all age groups. These results suggest that aging impairs the ability of canines to discriminate between task-relevant and -irrelevant stimuli. This is likely to be derived from impairments in cognitive domains such as visual memory and learning and selective attention.

  15. Determinants of dental care utilization for diverse ethnic and age groups.

    PubMed

    Davidson, P L; Andersen, R M

    1997-05-01

    Dental services utilization in the past 12 months was compared across population-based samples of African-American, Navajo, Lakota, Hispanic, and White adults participating in the WHO International Collaborative Study of Oral Health Outcomes (ICS-II) at USA research locations. Bivariate results revealed that ethnic minority groups in both age cohorts reported significantly fewer dental visits in the past 12 months compared with White adults. When dentate status was controlled for, age cohort differences were not significant in Baltimore (African-American and White) and San Antonio (Hispanic and White) research locations. In contrast, older Native Americans (65-74 years) reported visiting the dentist significantly less often compared with their middle-aged (35-44 years) counterparts. Multivariate results indicated that generalizable variables were associated with dental contact in every ICS-II USA ethnic group (i.e., dentate, usual source of dental care, oral pain). Among the diverse ethnic groups, other determinants presented a varied pattern of risk factors for underutilizing dental care. Information on ethnic-specific risk factors can be used to design culturally appropriate and acceptable oral health promotion programs. Generalizable risk factors across ethnic groups inform oral health policy-makers about changing national priorities for promoting oral health. PMID:9549991

  16. Reddening and age for 13 southern Galactic open clusters determined from integrated spectra

    NASA Astrophysics Data System (ADS)

    Ahumada, A. V.; Clariá, J. J.; Bica, E.; Dutra, C. M.; Torres, M. C.

    2001-10-01

    In this study we present flux-calibrated integrated spectra in the range 3800-6800 Å for 13 concentrated open clusters with Galactic longitudes between 219deg and 316deg, nine of which have not been previously studied. Using the equivalent widths of the Balmer lines and comparing the cluster spectra with template spectra of Magellanic Clouds and Galactic star clusters with known parameters, we derive both foreground interstellar reddening values and age. For nine clusters these two parameters have been determined for the first time, while for the rest of the sample the results show good agreement with previous studies. The present analysis indicates four very young (Hogg 11, NGC 5606, vdB-RN 80 and Pismis 17), seven moderately young (ESO 429-SC13, Hogg 3, Hogg 12, Haffner 7, BH 87, NGC 2368 and Bochum 12) and two intermediate-age (Berkeley 75 and NGC 2635) open clusters. The derived foreground interstellar reddening values are in the range 0.00 <= E(B-V) <= 0.38. The age and reddening distributions of the present sample of relatively faint open clusters match those of open clusters with known parameters in a 90deg sector centered at l = 270deg. Based on observations made at Complejo Astronómico El Leoncito, which is operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina and the National Universities of La Plata, Córdoba and San Juan, Argentina.

  17. The reliability of chronological age determination by means of mandibular third molar development in subjects in Croatia.

    PubMed

    Legović, Mario; Sasso, Anja; Legović, Izak; Brumini, Gordana; Cabov, Tomislav; Slaj, Martina; Vancura, Irena; Lapter, Marina

    2010-01-01

    The aim of this study was to determine the development of the mandibular third molar and its relation to chronological age. The evaluated material consisted of 979 orthopantomograms of patients of Croatian Caucasian origin aged between 5.7 and 14.6 years. Third molar developmental stages were evaluated according to the stages proposed by Nolla. The frequencies of different stages of mineralization and the mean value of the mineralization of the mandibular third molars with regard to age, gender, and size of the mandible were determined and the coefficient of correlation determined between the age of the subject and the stage of development of the mandibular molars. Statistically significant correlation was determined between mineralization of the mandibular third molar and chronological age of the subjects (boys, mandibular left third molar r = 0.779, right third molar r = 0.793; girls, mandibular left third molar r = 0.746, right third molar r = 0.725). It can be concluded that the accuracy of age estimation based on Nolla's method is applicable for Croatian children.

  18. Lithium battery aging model based on Dakin's degradation approach

    NASA Astrophysics Data System (ADS)

    Baghdadi, Issam; Briat, Olivier; Delétage, Jean-Yves; Gyan, Philippe; Vinassa, Jean-Michel

    2016-09-01

    This paper proposes and validates a calendar and power cycling aging model for two different lithium battery technologies. The model development is based on previous SIMCAL and SIMSTOCK project data. In these previous projects, the effect of the battery state of charge, temperature and current magnitude on aging was studied on a large panel of different battery chemistries. In this work, data are analyzed using Dakin's degradation approach. In fact, the logarithms of battery capacity fade and the increase in resistance evolves linearly over aging. The slopes identified from straight lines correspond to battery aging rates. Thus, a battery aging rate expression function of aging factors was deduced and found to be governed by Eyring's law. The proposed model simulates the capacity fade and resistance increase as functions of the influencing aging factors. Its expansion using Taylor series was consistent with semi-empirical models based on the square root of time, which are widely studied in the literature. Finally, the influence of the current magnitude and temperature on aging was simulated. Interestingly, the aging rate highly increases with decreasing and increasing temperature for the ranges of -5 °C-25 °C and 25 °C-60 °C, respectively.

  19. Aging effect on the phase evolution of water-based sol-gel hydroxyapatite.

    PubMed

    Liu, Dean-Mo; Troczynski, T; Tseng, Wenjea J

    2002-02-01

    In a number of recent reports on the synthesis of sol-gel hydroxyapatite, aging of the precursor solution has been found to be critical in developing an apatitic phase. Critical aging time is required to complete reaction between Ca and P molecular precursors to form a desired intermediate complex that permits a further transformation to apatite phase under appropriate thermal treatment. In this investigation, we employed a water-based sol-gel process recently developed to fabricate hydroxyapatite at relatively low temperatures. The aging effect on apatite formation was systematically studied in terms of aging time and temperature. Experimental results show that the aging time is considerably reduced as aging temperature rises. Long-term thermal aging was unfavorable for apatite formation. The optimal aging parameters for apatite formation were experimentally determined, which was further consolidated into a phase evolution map. Aging kinetic was investigated by monitoring the variation of solution pH, following the determination of an apparent activation energy, which has a value as high as 10.35 kcal/mol, for the chemical reaction occurring upon aging. Optimal solution chemistry was elucidated based on the corresponding phase evolution map.

  20. The analysis of aging skin based on multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Wu, Shulian; Li, Hui; Zhang, Xiaoman; Li, Zhifang; Xu, Shufei

    2010-11-01

    Aging is a very important issue not only in dermatology, but also in cosmetic science. Cutaneous aging involves both chronological and photoaging aging process. The chronological aging is induced with the passage of time. And the photoaging skin is the extrinsic aging caused by sun exposure. The aim of this study is to use multiphoton microscopy (MPM) in vivo to assess intrinsic-age-related and photo-age-related difference. The changes of dermal collagen are measured in quantitively. The algorithm that we used automatically produced the transversal dermal map from MPM. Others, the texture of dermis are analyzed by Fourier transform and Gray Level Co-occurrence Matrix. And the object extraction in textured images is proposed based on the method in object edge extraction, and the aim of it is to detect the object hidden in the skin texture in difference aging skin. The result demonstrates that the approach is effective in detecting the object in epidermis and dermis textured image in different aging skin. It could help to further understand the aging mechanism.

  1. AGE DETERMINATION FOR 346 NEARBY STARS IN THE HERSCHEL DEBRIS SURVEY

    SciTech Connect

    Vican, Laura

    2012-06-15

    DEBRIS is a flux-limited survey of nearby stars (spectral types A-M) for evidence of debris disks with the Herschel Space Observatory. One goal of the survey is to determine disk incidence as a function of various stellar parameters. Understanding debris disk evolution depends on knowledge of the precise age of stars around which these debris disks are found. However, finding ages for field stars is notoriously difficult. Furthermore, in an unbiased sample like DEBRIS, one is working with stars across many spectral types. This requires a multi-method approach to age determination. In this paper, we outline several methods of age determination broken down by spectral type, including some strengths and limitations of each method. In total, we were able to calculate ages for 263 of 274 F-, G-, and K-type stars, and all 83 A-type stars in the DEBRIS sample.

  2. Dental age estimation based on third molar eruption in First Nation people of Canada.

    PubMed

    Schmeling, A; Olze, A; Pynn, B R; Kraul, V; Schulz, R; Heinecke, A; Pfeiffer, H

    2010-12-01

    Forensic age estimation of living subjects has become an increasing focus of interest in modern society. One main criterion for dental age estimation in the relevant age group is the evaluation of third molar eruption. The importance of ethnic variation in dental development requires population specific data for dental age evaluation. In the present study, we determined the stages of third molar eruption in 347 female and 258 male First Nations people of Canada aged 11 to 29 years based on radiological evidence from 605 conventional orthopantomograms. The results presented here provide data on the age of alveolar, gingival, and complete eruption of the third molars in the occlusal plane that can be used for forensic estimation of the minimum and most probable ages of investigated individuals.

  3. 20 CFR 410.426 - Determining total disability: Age, education, and work experience criteria.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Total Disability or Death Due to Pneumoconiosis § 410.426 Determining total disability: Age, education, and...

  4. 20 CFR 410.426 - Determining total disability: Age, education, and work experience criteria.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Total Disability or Death Due to Pneumoconiosis § 410.426 Determining total disability: Age, education, and...

  5. 76 FR 60112 - Culturally Significant Objects Imported for Exhibition Determinations: “Byzantium and Islam: Age...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Byzantium and Islam: Age of... Islam: Age of Transition (7th-9th Century),'' imported from abroad for temporary exhibition within...

  6. Physical Attractiveness, Age, and Sex as Determinants of Reactions to Resumes.

    ERIC Educational Resources Information Center

    Quereshi, M. Y.; Kay, Janet P.

    1986-01-01

    Physical attractiveness, age, and sex were manipulated to determine their effect on the evaluation of 54 hypothetical applicants' resumes for three different jobs by 60 Master's in Business Administration students. Physical attractiveness favorably influenced the suitability ratings for all jobs; raters' sex and age were not significant but…

  7. Age dependency of base modification in rabbit liver DNA

    NASA Technical Reports Server (NTRS)

    Yamamoto, O.; Fuji, I.; Yoshida, T.; Cox, A. B.; Lett, J. T.

    1988-01-01

    Age-related modifications of DNA bases have been observed in the liver of the New Zealand white (NZW) rabbit (Oryctolagus cuniculus), a lagomorph with a median life span in captivity of 5-7 yr. The ages of the animals studied ranged from 6 wk to 9 yr. After the DNA had been extracted from the liver cell nuclei and hydrolyzed with acid, the bases were analyzed by column chromatography with Cellulofine gels (GC-15-m). Two peaks in the chromatogram, which eluted before the four DNA bases, contained modified bases. Those materials, which were obtained in relatively large amounts from old animals, were highly fluorescent, and were shown to be crosslinked base products by mass spectrometry. The yield of crosslinked products versus rabbit age (greater than 0.5 yr) can be fitted by an exponential function (correlation coefficient: 0.76 +/- 0.09).

  8. Effect of Radium mobility on the U-Pb systematic and age determination of uraninite.

    NASA Astrophysics Data System (ADS)

    Deloule, Etienne; Brouand, Marc

    2014-05-01

    The U-Pb radio chronometer is commonly used to date the formation of uraninite, a major component of uranium deposit. Uraninite was first used in 1905, when Rutherford determines ages up to 500 Ma in using their He/U ratio, and in 1907 when Boltwood determine the first U-Pb ages (413-535 Ma). During the last decade, in situ U-Pb datation on Uraninite has been developed, either in using 'chemical ages' with the determination by EMP of U and Pb contents, either in using 'isotopic ages' with the determination of Pb and U isotopic ratios and contents by SIMS, providing a large amount of age from archean up to Cenozoic ages. It is noticeable that the determination of chemical age relies on the assumption that the U-Pb system stay closed over time. This assumption can be supported by many isotopic measurements providing concordant or close to concordance 238U-206Pb and 235U-207Pb ages. However, during the last year, SIMS U-Pb age determination on Uraninite from the Imouraren (Niger) uranium deposit provides contrasted results. On one hand, samples provide concordant U-Pb ages with an average value of 99 ±2 Ma. On the other hand, samples provide largely discordant ages, with 207Pb/206Pb ages up to 340 Ma. Duplicated measurements and careful data examination allowed us to discard any common lead contamination as a source of discordance. Therefore we set the in situ measurement of the U series nuclides 238U - 234U - 230Th - 226Ra. The high transmission at high mass resolution of the CRPG -Cameca IMS 1270 ion microprobe allowed us to get significant secondary beam intensities for the smaller isotopes and to determine the activity ratios with a few % precision. These measurements points out that 234U and 230Th are at equilibrium with 238U, when 226Ra may be largely depleted, up to 50%. This points out that in the geological context of the deposit, hydrothermal fluids may leach Ra. To explain the observed discordant ages, Ra should have been lost during a large amount of time

  9. Age determination of plutonium material in nuclear forensics by thermal ionisation mass spectrometry.

    PubMed

    Wallenius, M; Mayer, K

    2000-02-01

    Age is a key parameter when deducing the history of plutonium material, i.e. the plutonium produced in the nuclear reactors. This is of vital importance, when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determine the age of plutonium material by thermal ionisation mass spectrometry using independent parent/daughter relations. This has been demonstrated for Reference Materials of known ages as well as for real samples. The already established method using gamma spectrometry is compared to this.

  10. [Morphofunctional and molecular bases of pineal gland aging].

    PubMed

    Khavinson, V Kh; Lin'kova, N S

    2012-01-01

    The review analyzed morphology, molecular and functional aspects of pineal gland aging and methods of it correction. The pineal gland is central organ, which regulates activity of neuroimmunoendocrine, antioxidant and other organisms systems. Functional activity of pineal gland is discreased at aging, which is the reason of melatonin level changing. The molecular and morphology research demonstrated, that pineal gland hadn't strongly pronounced atrophy at aging. Long-term experience showed, that peptides extract of pineal gland epithalamin and synthetic tetrapeptide on it base epithalon restored melatonin secretion in pineal gland and had strong regulatory activity at neuroimmunoendocrine and antioxidant organism systems.

  11. Determination of a Change Point in the Age at Diagnosis of Breast Cancer Using a Survival Model.

    PubMed

    Abdollahi, Mahbubeh; Hajizadeh, Ebrahim; Baghestani, Ahmad Reza; Haghighat, Shahpar

    2016-01-01

    Breast cancer, the second cause of cancer-related death after lung cancer and the most common cancer in women after skin cancer, is curable if detected in early stages of clinical presentation. Knowledge as to any age cut-off points which might have significance for prognostic groups is important in screening and treatment planning. Therefore, determining a change-point could improve resource allocation. This study aimed to determine if a change point for survival might exist in the age of breast cancer diagnosis. This study included 568 cases of breast cancer that were registered in Breast Cancer Research Center, Tehran, Iran, during the period 1986-2006 and were followed up to 2012. In the presence of curable cases of breast cancer, a change point in the age of breast cancer diagnosis was estimated using a mixture survival cure model. The data were analyzed using SPSS (versions 20) and R (version 2.15.0) software. The results revealed that a change point in the age of breast cancer diagnosis was at 50 years age. Based on our estimation, 35% of the patients diagnosed with breast cancer at age less than or equal to 50 years of age were cured while the figure was 57% for those diagnosed after 50 years of age. Those in the older age group had better survival compared to their younger counterparts during 12 years of follow up. Our results suggest that it is better to estimate change points in age for cancers which are curable in early stages using survival cure models, and that the cure rate would increase with timely screening for breast cancer.

  12. Factors Influencing the Self-Determination of Transition-Age Youth with High-Incidence Disabilities

    ERIC Educational Resources Information Center

    Pierson, Melinda R.; Carter, Erik W.; Lane, Kathleen Lynne; Glaeser, Barbara C.

    2008-01-01

    Recognizing the contributions of self-determination to improved outcomes for transition-age youth with disabilities, researchers are increasingly directing their efforts toward identifying factors associated with (a) these students' acquisition of skills that enhance self-determination and (b) educators' efforts to promote opportunities to be…

  13. 20 CFR 404.1583 - How we determine disability for blind persons who are age 55 or older.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1583 How we determine disability for blind persons who are age 55 or older. We will...

  14. 20 CFR 404.1583 - How we determine disability for blind persons who are age 55 or older.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1583 How we determine disability for blind persons who are age 55 or older. We will...

  15. 20 CFR 404.1583 - How we determine disability for blind persons who are age 55 or older.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1583 How we determine disability for blind persons who are age 55 or older. We will...

  16. 20 CFR 404.1583 - How we determine disability for blind persons who are age 55 or older.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1583 How we determine disability for blind persons who are age 55 or older. We will...

  17. 20 CFR 404.1583 - How we determine disability for blind persons who are age 55 or older.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FEDERAL OLD-AGE, SURVIVORS AND DISABILITY INSURANCE (1950- ) Determining Disability and Blindness Blindness § 404.1583 How we determine disability for blind persons who are age 55 or older. We will...

  18. Ultrasound determination of gestational age using placental thickness in female dogs: an experimental study.

    PubMed

    Maldonado, André Luiz Louzada; Araujo Júnior, Edward; Mendonça, Débora Sartori; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes; Ajzen, Sérgio Aron

    2012-01-01

    Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P < 0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age -0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys. PMID:22848867

  19. Ultrasound Determination of Gestational Age Using Placental Thickness in Female Dogs: An Experimental Study

    PubMed Central

    Maldonado, André Luiz Louzada; Araujo Júnior, Edward; Mendonça, Débora Sartori; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes; Ajzen, Sérgio Aron

    2012-01-01

    Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P < 0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age −0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys. PMID:22848867

  20. Human Age Estimation Based on Locality and Ordinal Information.

    PubMed

    Li, Changsheng; Liu, Qingshan; Dong, Weishan; Zhu, Xiaobin; Liu, Jing; Lu, Hanqing

    2015-11-01

    In this paper, we propose a novel feature selection-based method for facial age estimation. The face aging is a typical temporal process, and facial images should have certain ordinal patterns in the aging feature space. From the geometrical perspective, a facial image can be usually seen as sampled from a low-dimensional manifold embedded in the original high-dimensional feature space. Thus, we first measure the energy of each feature in preserving the underlying local structure information and the ordinal information of the facial images, respectively, and then we intend to learn a low-dimensional aging representation that can maximally preserve both kinds of information. To further improve the performance, we try to eliminate the redundant local information and ordinal information as much as possible by minimizing nonlinear correlation and rank correlation among features. Finally, we formulate all these issues into a unified optimization problem, which is similar to linear discriminant analysis in format. Since it is expensive to collect the labeled facial aging images in practice, we extend the proposed supervised method to a semi-supervised learning mode including the semi-supervised feature selection method and the semi-supervised age prediction algorithm. Extensive experiments are conducted on the FACES dataset, the Images of Groups dataset, and the FG-NET aging dataset to show the power of the proposed algorithms, compared to the state-of-the-arts. PMID:26470062

  1. The determination of male adult age at death by central and posterior coxal analysis--a preliminary study.

    PubMed

    Rougé-Maillart, Clotilde; Telmon, Norbert; Rissech, Carme; Malgosa, Assumption; Rougé, Daniel

    2004-03-01

    In forensic anthropological analysis, the pelvis is of particular interest as it is often a comparatively well-preserved part of the skeleton. This study in age determination uses the acetabulum, the central element of the pelvis, as a complement to the examination of the auricular surface. The test sample consisted of 30 individuals. First, the authors studied the auricular surface using the Lovejoy criteria. Second, they isolated four criteria based on chronological changes in the acetabulum. Third, they conducted an evaluation of each of these variables. The study examines the correlation between these criteria and the age of the individuals. A significant correlation was found between the acetabular criteria and age, and between the acetabular criteria and the Lovejoy criteria of the auricular surface. For forensic purposes, the acetabulum is an effective predictor in the determination of age. This newly proposed method explores the same criteria of ageing as the Lovejoy method. The combination of the two methods produces relatively consistent results in the estimation of age.

  2. Mapping of Planetary Surface Age Based on Crater Statistics Obtained by AN Automatic Detection Algorithm

    NASA Astrophysics Data System (ADS)

    Salih, A. L.; Mühlbauer, M.; Grumpe, A.; Pasckert, J. H.; Wöhler, C.; Hiesinger, H.

    2016-06-01

    The analysis of the impact crater size-frequency distribution (CSFD) is a well-established approach to the determination of the age of planetary surfaces. Classically, estimation of the CSFD is achieved by manual crater counting and size determination in spacecraft images, which, however, becomes very time-consuming for large surface areas and/or high image resolution. With increasing availability of high-resolution (nearly) global image mosaics of planetary surfaces, a variety of automated methods for the detection of craters based on image data and/or topographic data have been developed. In this contribution a template-based crater detection algorithm is used which analyses image data acquired under known illumination conditions. Its results are used to establish the CSFD for the examined area, which is then used to estimate the absolute model age of the surface. The detection threshold of the automatic crater detection algorithm is calibrated based on a region with available manually determined CSFD such that the age inferred from the manual crater counts corresponds to the age inferred from the automatic crater detection results. With this detection threshold, the automatic crater detection algorithm can be applied to a much larger surface region around the calibration area. The proposed age estimation method is demonstrated for a Kaguya Terrain Camera image mosaic of 7.4 m per pixel resolution of the floor region of the lunar crater Tsiolkovsky, which consists of dark and flat mare basalt and has an area of nearly 10,000 km2. The region used for calibration, for which manual crater counts are available, has an area of 100 km2. In order to obtain a spatially resolved age map, CSFDs and surface ages are computed for overlapping quadratic regions of about 4.4 x 4.4 km2 size offset by a step width of 74 m. Our constructed surface age map of the floor of Tsiolkovsky shows age values of typically 3.2-3.3 Ga, while for small regions lower (down to 2.9 Ga) and higher

  3. Reliability in age determination by pulp/tooth ratio in upper canines in skeletal remains.

    PubMed

    Cameriere, Roberto; Brogi, Giuseppe; Ferrante, Luigi; Mirtella, Dora; Vultaggio, Claudia; Cingolani, Mariano; Fornaciari, Gino

    2006-07-01

    Estimation of age of skeletal remains is one of the most complex questions for anthropologists. The most common macroscopic methods are based on dental wear and histological evaluation of bone remodeling. These methods are often qualitative, require great technical expertise, and have proved inexact in the estimation of ages over 50 years. Certain dental methods investigate the apposition of secondary dentine, in the study of tooth cross-sections, and X-rays to study width, height, and pulp area. The primary author previously proposed a method of estimating the age of a living person based on the pulp/tooth ratio (PTR) method in the upper canines. The aim of the present study is to verify whether the PTR method can also be used to estimate the age at death of skeletal remains. This paper investigates the study of historical samples of known age as a means to validate the proposed method.

  4. Globular cluster ages determined from the Oosterhoff period-metallicity effect using oxygen-enhanced isochrones. III

    NASA Astrophysics Data System (ADS)

    Sandage, Allan

    1993-08-01

    The new brighter calibration of absolute luminosities of RR Lyrae stars by about 0.25 mag as a function of metallicity via the Oosterhoff period effect gives a revised age of the Galactic globular cluster system as 14 Gyr when used with the oxygen-enhanced main-sequence termination models of Bergbush and VandenBerg (1992). There is no correlation of cluster age with metallicity. The presence or absence of age differences between any two clusters is neither proof nor disproof of the Eggen-Lynden Bell-Sandage model of the formation of the Galaxy by collapse. If there were different density regimes within the initial density fluctuation that was the protogalaxy, then there has been a hierarchy of collapse times for the various parts of the present Galaxy. The age of the universe is 15 Gyr, based on the age of the Galaxy at 14 Gyr, to which 1 Gyr is added for the gestation time of the galaxies. The ratio of this age to the inverse Hubble constant with H(0) about 45 km/s Mpc, based on a recent concordant determination using supernovae of type Ia, is close to the critical value of 2/3 required if the deceleration is caused by a mean density just equal to that needed for closure. For the first time, these new data give the possibility that Omega = 1 from this timing test.

  5. Evaluation of a Community-Based Aging Intervention Program

    ERIC Educational Resources Information Center

    Hsu, Hui-Chuan; Wang, Chun-Hou; Chen, Yi-Chun; Chang, Ming-Chen; Wang, Jean

    2010-01-01

    This study evaluated the outcome and process of a community-based aging intervention program for the elderly in Taiwan. The program included education on nutrition and dietary behavior and on physical activities. Outcome and process evaluations were conducted. The program may have had some effects on decreasing some dietary behavioral problems and…

  6. Cosmogenic Ne-21 Production Rates in H-Chondrites Based on Cl-36 - Ar-36 Ages

    NASA Technical Reports Server (NTRS)

    Leya, I.; Graf, Th.; Nishiizumi, K.; Guenther, D.; Wieler, R.

    2000-01-01

    We measured Ne-21 production rates in 14 H-chondrites in good agreement with model calculations. The production rates are based on Ne-21 concentrations measured on bulk samples or the non-magnetic fraction and Cl-36 - Ar-36 ages determined from the metal phase.

  7. Age determination of fish from scales; method and application to fish cultural problems

    USGS Publications Warehouse

    Hile, Ralph

    1936-01-01

    THE SCIENCE of "scale reading", or determination of the age of fish from the examination of their scales, is less than 40 years old. Yet today the publications on the subject are to be numbered by the hundreds, and there is scarcely any phase of fish and fishery work that has not been benefited by this powerful tool for investigation. Fish culture is no exception to this rule. It is because of the increasing interest of fish culturists in scale reading and their numerous requests for information on the subject, that I have been asked to prepare a brief discussion of the method of age determination in fishes.

  8. Incompatible Ages for Clearwing Butterflies Based on Alternative Secondary Calibrations.

    PubMed

    Garzón-Orduña, Ivonne J; Silva-Brandão, Karina L; Willmott, Keith R; Freitas, André V L; Brower, Andrew V Z

    2015-09-01

    The recent publication of a time-tree for the plant family Solanaceae (nightshades) provides the opportunity to use independent calibrations to test divergence times previously inferred for the diverse Neotropical butterfly tribe Ithomiini. Ithomiini includes clades that are obligate herbivores of Solanaceae, with some genera feeding on only one genus. We used 8 calibrations extracted from the plant tree in a new relaxed molecular-clock analysis to produce an alternative temporal framework for the diversification of ithomiines. We compared the resulting age estimates to: (i) a time-tree obtained using 7 secondary calibrations from the Nymphalidae tree of Wahlberg et al. (2009), and (ii) Wahlberg et al.'s (2009) original age estimates for the same clades. We found that Bayesian clock estimates were rather sensitive to a variety of analytical parameters, including taxon sampling. Regardless of this sensitivity however, ithomiine divergence times calibrated with the ages of nightshades were always on average half the age of previous estimates. Younger dates for ithomiine clades appear to fit better with factors long suggested to have promoted diversification of the group such as the uplifting of the Andes, in the case of montane genera. Alternatively, if ithomiines are as old as previous estimates suggest, the recent ages inferred for the diversification of Solanaceae seem likely to be seriously underestimated. Our study exemplifies the difficulty of testing hypotheses of divergence times and of choosing between alternative dating scenarios, and shows that age estimates based on seemingly plausible calibrations may be grossly incongruent. PMID:26012872

  9. Incompatible Ages for Clearwing Butterflies Based on Alternative Secondary Calibrations.

    PubMed

    Garzón-Orduña, Ivonne J; Silva-Brandão, Karina L; Willmott, Keith R; Freitas, André V L; Brower, Andrew V Z

    2015-09-01

    The recent publication of a time-tree for the plant family Solanaceae (nightshades) provides the opportunity to use independent calibrations to test divergence times previously inferred for the diverse Neotropical butterfly tribe Ithomiini. Ithomiini includes clades that are obligate herbivores of Solanaceae, with some genera feeding on only one genus. We used 8 calibrations extracted from the plant tree in a new relaxed molecular-clock analysis to produce an alternative temporal framework for the diversification of ithomiines. We compared the resulting age estimates to: (i) a time-tree obtained using 7 secondary calibrations from the Nymphalidae tree of Wahlberg et al. (2009), and (ii) Wahlberg et al.'s (2009) original age estimates for the same clades. We found that Bayesian clock estimates were rather sensitive to a variety of analytical parameters, including taxon sampling. Regardless of this sensitivity however, ithomiine divergence times calibrated with the ages of nightshades were always on average half the age of previous estimates. Younger dates for ithomiine clades appear to fit better with factors long suggested to have promoted diversification of the group such as the uplifting of the Andes, in the case of montane genera. Alternatively, if ithomiines are as old as previous estimates suggest, the recent ages inferred for the diversification of Solanaceae seem likely to be seriously underestimated. Our study exemplifies the difficulty of testing hypotheses of divergence times and of choosing between alternative dating scenarios, and shows that age estimates based on seemingly plausible calibrations may be grossly incongruent.

  10. Thyroid and Aging or the Aging Thyroid? An Evidence-Based Analysis of the Literature

    PubMed Central

    2013-01-01

    Thyroid hormone production, metabolism, and action change with aging. The reference ranges for serum thyrotropin and thyroid hormones are derived mainly from younger populations. Thus, the prevalence of subclinical thyroid dysfunction is increased greatly in the elderly. However, it is unclear whether mild thyroid dysfunction in the elderly is associated with adverse outcomes. In this review, we discuss current evidence-based literature on thyroid function in the elderly and whether subclinical thyroid dysfunction in the elderly should be treated. PMID:24106641

  11. Accuracy of egg flotation throughout incubation to determine embryo age and incubation day in waterbird nests

    USGS Publications Warehouse

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2010-01-01

    Floating bird eggs to estimate their age is a widely used technique, but few studies have examined its accuracy throughout incubation. We assessed egg flotation for estimating hatch date, day of incubation, and the embryo's developmental age in eggs of the American Avocet (Recurvirostra americana), Black-necked Stilt (Himantopus mexicanus), and Forster's Tern (Sterna forsteri). Predicted hatch dates based on egg flotation during our first visit to a nest were highly correlated with actual hatch dates (r = 0.99) and accurate within 2.3 ± 1.7 (SD) days. Age estimates based on flotation were correlated with both day of incubation (r = 0.96) and the embryo's developmental age (r = 0.86) and accurate within 1.3 ± 1.6 days and 1.9 ± 1.6 days, respectively. However, the technique's accuracy varied substantially throughout incubation. Flotation overestimated the embryo's developmental age between 3 and 9 days, underestimated age between 12 and 21 days, and was most accurate between 0 and 3 days and 9 and 12 days. Age estimates based on egg flotation were generally accurate within 3 days until day 15 but later in incubation were biased progressively lower. Egg flotation was inaccurate and overestimated embryo age in abandoned nests (mean error: 7.5 ± 6.0 days). The embryo's developmental age and day of incubation were highly correlated (r = 0.94), differed by 2.1 ± 1.6 days, and resulted in similar assessments of the egg-flotation technique. Floating every egg in the clutch and refloating eggs at subsequent visits to a nest can refine age estimates.

  12. Age, growth and size interact with stress to determine life span and mortality.

    PubMed

    Roach, Deborah Ann

    2012-10-01

    Individuals in a large experimental field population, of the short-lived perennial species Plantago lanceolata, were followed to determine the sources of variation that influence mortality and life span. The design included multiple age groups with initially similar genetic structure, which made it possible to separate age effects from period effects and to identify the genetic component to variation in life span. During a period of stress, individuals of all ages showed parallel increases in mortality but different cohorts experienced this period of high mortality at different ages. This then influenced the distribution of life spans across cohorts. Age and size-age interactions influenced mortality during the period of stress. Smaller individuals died but only if they were old. Additionally, growth and age interacted with stress such that older individuals had negative growth and high mortality whereas younger individuals had positive growth and relatively lower mortality during stress. The results of this study show that it is not simply the environment that can have a major impact on demography in natural populations; rather, age, size and growth can interact with the environment to influence mortality and life span when the environment is stressful.

  13. Age, growth and size interact with stress to determine life span and mortality

    PubMed Central

    Roach, Deborah Ann

    2012-01-01

    Individuals in a large experimental field population, of the short-lived perennial species Plantago lanceolata, were followed to determine the sources of variation that influence mortality and life span. The design included multiple age groups with initially similar genetic structure, which made it possible to separate age effects from period effects and to identify the genetic component to variation in life span. During a period of stress, individuals of all ages showed parallel increases in mortality but different cohorts experienced this period of high mortality at different ages. This then influenced the distribution of life spans across cohorts. Age and size-age interactions influenced mortality during the period of stress. Smaller individuals died but only if they were old. Additionally, growth and age interacted with stress such that older individuals had negative growth and high mortality whereas younger individuals had positive growth and relatively lower mortality during stress. The results of this study show that it is not simply the environment that can have a major impact on demography in natural populations, rather, age, size and growth can interact with the environment to influence mortality and life span when the environment is stressful. PMID:22664575

  14. Genetic determination of telomere size in humans: A twin study of three age groups

    SciTech Connect

    Slagboom, P.E.; Droog, S.; Boomsma, D.I.

    1994-11-01

    Reduction of telomere length has been postulated to be a casual factor in cellular aging. Human telomeres terminate in tandemly arranged repeat arrays consisting of the (TTAGGG) motif. The length of these arrays in cells from human mitotic tissues is inversely related to the age of the donor, indicating telomere reduction with age. In addition to telemore length differences between different age cohorts, considerable variation is present among individuals of the same age. To investigate whether this variation can be ascribed to genetic influences, we have measured the size of terminal restriction fragments (TRFs) in HaeIII-digested genomic DNA from 123 human MZ and DZ twin pairs 2-95 years of age. The average rate of telomere shortening was 31 bp/year, which is similar to that observed by others. Statistical analysis in 115 pairs 2-63 years of age indicates a 78% heritability for mean TRF length in this age cohort. The individual differences in mean TRF length in blood, therefore, seem to a large extent to be genetically determined. 24 refs., 4 figs., 2 tabs.

  15. Age, growth and size interact with stress to determine life span and mortality.

    PubMed

    Roach, Deborah Ann

    2012-10-01

    Individuals in a large experimental field population, of the short-lived perennial species Plantago lanceolata, were followed to determine the sources of variation that influence mortality and life span. The design included multiple age groups with initially similar genetic structure, which made it possible to separate age effects from period effects and to identify the genetic component to variation in life span. During a period of stress, individuals of all ages showed parallel increases in mortality but different cohorts experienced this period of high mortality at different ages. This then influenced the distribution of life spans across cohorts. Age and size-age interactions influenced mortality during the period of stress. Smaller individuals died but only if they were old. Additionally, growth and age interacted with stress such that older individuals had negative growth and high mortality whereas younger individuals had positive growth and relatively lower mortality during stress. The results of this study show that it is not simply the environment that can have a major impact on demography in natural populations; rather, age, size and growth can interact with the environment to influence mortality and life span when the environment is stressful. PMID:22664575

  16. Determination of Age-Dependent Reference Ranges for Coagulation Tests Performed Using Destiny Plus

    PubMed Central

    Arslan, Fatma Demet; Serdar, Muhittin; Merve Ari, Elif; Onur Oztan, Mustafa; Hikmet Kozcu, Sureyya; Tarhan, Huseyin; Cakmak, Ozgur; Zeytinli, Merve; Yasar Ellidag, Hamit

    2016-01-01

    Background In order to apply the right treatment for hemostatic disorders in pediatric patients, laboratory data should be interpreted with age-appropriate reference ranges. Objectives The purpose of this study was to determining age-dependent reference range values for prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen tests, and D-dimer tests. Materials and Methods A total of 320 volunteers were included in the study with the following ages: 1 month - 1 year (n = 52), 2 - 5 years (n = 50), 6 - 10 years (n = 48), 11 - 17 years (n = 38), and 18 - 65 years (n = 132). Each volunteer completed a survey to exclude hemostatic system disorder. Using a nonparametric method, the lower and upper limits, including 95% distribution and 90% confidence intervals, were calculated. Results No statistically significant differences were found between PT and aPTT values in the groups consisting of children. Thus, the reference ranges were separated into child and adult age groups. PT and aPTT values were significantly higher in the children than in the adults. Fibrinogen values in the 6 - 10 age group and the adult age group were significantly higher than in the other groups. D-dimer levels were significantly lower in those aged 2 - 17; thus, a separate reference range was established. Conclusions These results support other findings related to developmental hemostasis, confirming that adult and pediatric age groups should be evaluated using different reference ranges. PMID:27617078

  17. Age determination in manatees using growth-layer-group counts in bone

    USGS Publications Warehouse

    Marmontel, M.; O'Shea, T.J.; Kochman, H.I.; Humphrey, S.R.

    1996-01-01

    Growth layers were observed in histological preparations of bones of known-age, known minimum-age, and tetracycline-marked free-ranging and captive Florida manatees (Trichechus manatus latirostris), substantiating earlier preliminary findings of other studies. Detailed analysis of 17 new case histories showed that growth-layer group (GLG) counts in the periotic bone were consistent with known age, or time since tetracycline administration, but were less reliable in other bones. GLG counts were also made in periotic bones of 1,196 Florida manatees of unknown age found dead from 1974 through 1991. These counts were conducted in order to assess variability and to determine relationships among estimated age, size, sex, and degree of bone resorption. Resorption can interfere with accuracy of GLG counts. This effect does not occur until ages greater than about 15 yr and body lengths greater than 300 cm are attained. GLGs were also observed in periotic bones of Antillean manatees (Trichechus manatus manatus) but were not validated against known-age specimens. Use of GLG counts in the periotic bone is suitable for application to studies of population dynamics and other age-related aspects of manatee biology.

  18. [Radiologically determined DMF index variations for forensic age estimation of young adults].

    PubMed

    Andreas, Olze; Mahlow, Andrea; Schmidt, Sven; Geserick, Gunther; Schmeling, Andreas

    2004-01-01

    The eruption and mineralization of third molars are the main criteria for dental age estimation of living people involved in criminal proceedings. Since the development of third molars is usually completed by the age of 19 or 20 years, this feature cannot be used to ascertain whether a person has attained the forensically relevant age of 21 years. This study examined whether the DMFT index or the third molar DFT index could supply reliable information enabling conclusions to be drawn about whether a person has reached the age of 21. To this end, 650 conventional orthopantomograms of German subjects aged 18 to 30 years were evaluated. The DMF index variations considered were found to be unsuitable for determining whether a person is over 21 because they displayed a weak correlation with age and considerable individual scatter. A high indicative value can only be attributed to a third molar DFT index of 4, although this is rarely observed in the relevant age group. An X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person has attained 21 years of age.

  19. Evaluations of mosquito age grading techniques based on morphological changes.

    PubMed

    Hugo, L E; Quick-Miles, S; Kay, B H; Ryan, P A

    2008-05-01

    Evaluations were made of the accuracy and practicality of mosquito age grading methods based on changes to mosquito morphology; including the Detinova ovarian tracheation, midgut meconium, Polovodova ovariole dilatation, ovarian injection, and daily growth line methods. Laboratory maintained Aedes vigilax (Skuse) and Culex annulirostris (Skuse) females of known chronological and physiological ages were used for these assessments. Application of the Detinova technique to laboratory reared Ae. vigilax females in a blinded trial enabled the successful identification of nulliparous and parous females in 83.7-89.8% of specimens. The success rate for identifying nulliparous females increased to 87.8-98.0% when observations of ovarian tracheation were combined with observations of the presence of midgut meconium. However, application of the Polovodova method only enabled 57.5% of nulliparous, 1-parous, 2-parous, and 3-parous Ae. vigilax females to be correctly classified, and ovarian injections were found to be unfeasible. Poor correlation was observed between the number of growth lines per phragma and the calendar age of laboratory reared Ae. vigilax females. In summary, morphological age grading methods that offer simple two-category predictions (ovarian tracheation and midgut meconium methods) were found to provide high-accuracy classifications, whereas methods that offer the separation of multiple age categories (ovariolar dilatation and growth line methods) were found to be extremely difficult and of low accuracy. The usefulness of the morphology-based methods is discussed in view of the availability of new mosquito age grading techniques based on cuticular hydrocarbon and gene transcription changes. PMID:18533427

  20. Determination of chronological aging parameters in epidermal keratinocytes by in vivo harmonic generation microscopy

    PubMed Central

    Liao, Yi-Hua; Chen, Szu-Yu; Chou, Sin-Yo; Wang, Pei-Hsun; Tsai, Ming-Rung; Sun, Chi-Kuang

    2012-01-01

    Skin aging is an important issue in geriatric and cosmetic dermatology. To quantitatively analyze changes in keratinocytes related to intrinsic aging, we exploited a 1230 nm-based in vivo harmonic generation microscopy, combining second- and third-harmonic generation modalities. 52 individuals (21 men and 31 women, age range 19–79) were examined on the sun-protected volar forearm. Through quantitative analysis by the standard algorithm provided, we found that the cellular and nuclear size of basal keratinocytes, but not that of granular cells, was significantly increased with advancing age. The cellular and nuclear areas, which have an increase of 0.51 μm2 and 0.15 μm2 per year, respectively, can serve as scoring indices for intrinsic skin aging. PMID:23304649

  1. Determination of patterns of regional cerebral glucose metabolism in normal aging and dementia

    SciTech Connect

    Alavi, A.; Chawluk, J.; Hurtig, H.; Dann, R.; Rosen, M.; Kushner, M.; Silver, F.; Reivich, M.

    1985-05-01

    Regional cerebral metabolic rates for glucose (rCMRGlc) were measured using 18F-FDG and positron emission tomography (PET) in 14 patients with probable Alzheimer's disease (AD) (age=64), 9 elderly controls (age=61), and 9 young controls (age=28). PET studies were performed without sensory stimulation or deprivation. Metabolic rates in individual brain regions were determined using an atlas overlay. Relative metabolic rates (rCMRGl c/global CMRGlc) were determined for all subjects. Comparison of young and elderly controls demonstrated significant decreases in frontal metabolism (rho<0.005) and right inferior parietal (IP) metabolism (rho<0.02) with normal aging. Patients with mild-moderate AD (NMAD) (n=8) when compared to age-matched controls, showed further reduction in right IP metabolism (rho<0.02). SAD patients also demonstrated metabolic decrements in left hemisphere language areas (rho<0.01). This latter finding is consistent with language disturbance observed late in the course of the disease. Out data reveal progressive changes in patterns of cerebral glucose utilization with aging and demential with reflect salient clinical features of these processes.

  2. Determinants of maximal instantaneous muscle power in women aged 50-75 years.

    PubMed

    De Vito, G; Bernardi, M; Forte, R; Pulejo, C; Macaluso, A; Figura, F

    1998-06-01

    The present study aimed at analysing the age-related decline in maximal muscle power (W) in 52 sedentary healthy women aged between 50 and 75 years to determine whether force or velocity is the major determinant. Maximal muscle power was estimated from two types of vertical jumps, squatting (SJ) and countermovement (CmJ), performed on a force platform. It was obtained by measuring the vertical force (F(opt)) applied to the body centre of gravity and calculating the corresponding vertical velocity (v(opt)). An age-related decline in absolute W was statistically significant in all the conditions examined and in both peak W and average power (W) values. The decrease in v(opt) was also statistically significant. Also F(opt) declined but this reduction was not statistically significant with the exception of the average value in CmJ. Not surprisingly the highest W were obtained in CmJ, and the difference in power production between the two types of jump showed an age-related decrement only in W. The main finding of the study was the demonstration that v(opt) was the critical determinant of the age-related decline in W in healthy elderly women.

  3. Age determination by magnetic resonance imaging of the wrist in adolescent male football players

    PubMed Central

    Dvorak, Jiri; George, John; Junge, Astrid; Hodler, Juerg

    2007-01-01

    Background In football there are established age‐related tournaments for males and females to guarantee equal chances within the game for all the different age groups. To prevent participation in the incorrect age group, and owing to the fact that in some Asian and African countries registration at birth is not compulsory, other methods of age determination need to be available. Standard radiographs of the left wrist have been used for assessment of skeletal age for many years. This is, however, not ethical in the sporting environment. Aim To study the possible use of magnetic resonance imaging (MRI), which has no radiation risk, in estimating the age of healthy adolescent football players. Methods The examination protocol was applied in four countries using, their respective MRI equipment using a 1‐T or 1.5‐T magnet and a wrist coil. 496 healthy male adolescent football players between the ages of 14 and 19 years from Switzerland, Malaysia, Algeria and Argentina were selected for the study. The degree of fusion of the left distal radial physis was determined by three independent raters by a newly developed grading system which can be used in future MRI epiphysial fusion grading studies. Results The inter‐rater reliability for grading was high (r = 0.91 and 0.92); all correlations were highly significant (p<0.001). The average age increased with a higher grading of fusion, and the correlation between age and grade of fusion was highly significant (r = 0.69, p<0.001). Only one player (0.8%) in the 16‐year‐old age group was graded as completely fused. Conclusion MRI of the wrist offers an alternative as a non‐invasive method of age determination in 14–19‐year‐old male adolescents. The grading system presented here clearly identifies the skeletal maturity by complete fusion in all MRI slices, which eliminates any risk associated with standard radiographic rating as determined by the International Atomic Energy Agency. PMID:17021001

  4. Optimization of arterial age prediction models based in pulse wave

    NASA Astrophysics Data System (ADS)

    Scandurra, A. G.; Meschino, G. J.; Passoni, L. I.; Pra, A. L. Dai; Introzzi, A. R.; Clara, F. M.

    2007-11-01

    We propose the detection of early arterial ageing through a prediction model of arterial age based in the coherence assumption between the pulse wave morphology and the patient's chronological age. Whereas we evaluate several methods, a Sugeno fuzzy inference system is selected. Models optimization is approached using hybrid methods: parameter adaptation with Artificial Neural Networks and Genetic Algorithms. Features selection was performed according with their projection on main factors of the Principal Components Analysis. The model performance was tested using the bootstrap error type .632E. The model presented an error smaller than 8.5%. This result encourages including this process as a diagnosis module into the device for pulse analysis that has been developed by the Bioengineering Laboratory staff.

  5. Late Na+ current and protracted electrical recovery are critical determinants of the aging myopathy

    PubMed Central

    Signore, Sergio; Sorrentino, Andrea; Borghetti, Giulia; Cannata, Antonio; Meo, Marianna; Zhou, Yu; Kannappan, Ramaswamy; Pasqualini, Francesco; O'Malley, Heather; Sundman, Mark; Tsigkas, Nikolaos; Zhang, Eric; Arranto, Christian; Mangiaracina, Chiara; Isobe, Kazuya; Sena, Brena F.; Kim, Junghyun; Goichberg, Polina; Nahrendorf, Matthias; Isom, Lori L.; Leri, Annarosa; Anversa, Piero; Rota, Marcello

    2015-01-01

    The aging myopathy manifests itself with diastolic dysfunction and preserved ejection fraction. We raised the possibility that, in a mouse model of physiological aging, defects in electromechanical properties of cardiomyocytes are important determinants of the diastolic characteristics of the myocardium, independently from changes in structural composition of the muscle and collagen framework. Here we show that an increase in the late Na+ current (INaL) in aging cardiomyocytes prolongs the action potential (AP) and influences temporal kinetics of Ca2+ cycling and contractility. These alterations increase force development and passive tension. Inhibition of INaL shortens the AP and corrects dynamics of Ca2+ transient, cell contraction and relaxation. Similarly, repolarization and diastolic tension of the senescent myocardium are partly restored. Thus, INaL offers inotropic support, but negatively interferes with cellular and ventricular compliance, providing a new perspective of the biology of myocardial aging and the aetiology of the defective cardiac performance in the elderly. PMID:26541940

  6. Self-Determination among Transition-Age Youth with Autism or Intellectual Disability: Parent Perspectives

    ERIC Educational Resources Information Center

    Carter, Erik W.; Lane, Kathleen Lynne; Cooney, Molly; Weir, Katherine; Moss, Colleen K.; Machalicek, Wendy

    2013-01-01

    This study examined 68 parents' views of the self-determination skills and capacities of their young adult children with autism spectrum disorders and intellectual disability (ages 19-21 years). Results indicated parents placed a high value on the importance of all seven component skills (i.e., choice-making skills, decision-making skills,…

  7. Determining the age of meteor streams with the retrospective evolution method

    NASA Astrophysics Data System (ADS)

    Ryabova, G. O.; Pleshanova, A. V.; Konstantinov, V. S.

    2008-08-01

    We show that the retrospective evolution method yields excessively large inaccuracies in determining the age of meteorid streams. The cause is in its sensitivity to the errors in the initial conditions. The study was fulfilled with the Geminid, Quadrantid, Orionid, Perseid, and Leonid meteor showers as an example.

  8. Age-Based Methods to Explore Time-Related Variables in Occupational Epidemiology Studies

    SciTech Connect

    Janice P. Watkins, Edward L. Frome, Donna L. Cragle

    2005-08-31

    Although age is recognized as the strongest predictor of mortality in chronic disease epidemiology, a calendar-based approach is often employed when evaluating time-related variables. An age-based analysis file, created by determining the value of each time-dependent variable for each age that a cohort member is followed, provides a clear definition of age at exposure and allows development of diverse analytic models. To demonstrate methods, the relationship between cancer mortality and external radiation was analyzed with Poisson regression for 14,095 Oak Ridge National Laboratory workers. Based on previous analysis of this cohort, a model with ten-year lagged cumulative radiation doses partitioned by receipt before (dose-young) or after (dose-old) age 45 was examined. Dose-response estimates were similar to calendar-year-based results with elevated risk for dose-old, but not when film badge readings were weekly before 1957. Complementary results showed increasing risk with older hire ages and earlier birth cohorts, since workers hired after age 45 were born before 1915, and dose-young and dose-old were distributed differently by birth cohorts. Risks were generally higher for smokingrelated than non-smoking-related cancers. It was difficult to single out specific variables associated with elevated cancer mortality because of: (1) birth cohort differences in hire age and mortality experience completeness, and (2) time-period differences in working conditions, dose potential, and exposure assessment. This research demonstrated the utility and versatility of the age-based approach.

  9. Running rescues a fear-based contextual discrimination deficit in aged mice

    PubMed Central

    Wu, Melody V.; Luna, Victor M.; Hen, René

    2015-01-01

    Normal aging and exercise exert extensive, often opposing, effects on the dentate gyrus (DG) of the hippocampus altering volume, synaptic function, and behaviors. The DG is especially important for behaviors requiring pattern separation—a cognitive process that enables animals to differentiate between highly similar contextual experiences. To determine how age and exercise modulate pattern separation in an aversive setting, young, aged, and aged mice provided with a running wheel were assayed on a fear-based contextual discrimination task. Aged mice showed a profound impairment in contextual discrimination compared to young animals. Voluntary exercise rescued this deficit to such an extent that behavioral pattern separation of aged-run mice was now similar to young animals. Running also resulted in a significant increase in the number of immature neurons with tertiary dendrites in aged mice. Despite this, neurogenesis levels in aged-run mice were still considerably lower than in young animals. Thus, mechanisms other than DG neurogenesis likely play significant roles in improving behavioral pattern separation elicited by exercise in aged animals. PMID:26321926

  10. Aging process on spectrally determined spontaneous baroreflex sensitivity: a 5-year prospective study.

    PubMed

    Fauvel, Jean-Pierre; Cerutti, Catherine; Mpio, Ignace; Ducher, Michel

    2007-09-01

    The interindividual age-related decrease in baroreflex sensitivity (BRS) was reported in many cross-sectional studies. However, the long-term intraindividual decrease in BRS has never been confirmed by longitudinal studies. Data obtained from a 5-year prospective study designed to assess the 5-year stress effects on blood pressure (BP) provided the opportunity to assess longitudinal aging process on spectrally determined BRS (S-BRS) using the cross spectral analysis. This analysis was carried out in 205 men aged between 18 and 50 years who had 2 valid beat to beat BP recordings (Finapress) at a mean 5-year interval. At inclusion and at end of follow-up, S-BRS was significantly correlated with age (r=-0.50, P<0.001, r=-0.33, P<0.001 respectively). Interestingly, the slopes and the intercepts were not significantly different at a 5-year interval. This result is in favor of the good reproducibility of S-BRS. The attenuation with age of S-BRS was calculated at 3.6% a year. This decrease was slightly higher than the one obtained with the baseline data (2.3% per year). This longitudinal study provided, for the first time, an estimate of the slope of the age-related physiological S-BRS decrease in a mid-aged healthy male population. Our findings reinforce the interest of evaluating spontaneous BRS reported to predict hypertension and cardiovascular events in various populations.

  11. Ecological determinants of mean family age of angiosperm trees in forest communities in China

    PubMed Central

    Qian, Hong; Chen, Shengbin

    2016-01-01

    Species assemblage in a local community is determined by the interplay of evolutionary and ecological processes. The Tropical Niche Conservatism hypothesis proposes mechanisms underlying patterns of biodiversity in biological communities along environmental gradients. This hypothesis predicts that, among other things, clades in areas with warm or wet environments are, on average, older than those in areas with cold or dry environments. Focusing on angiosperm trees in forests, this study tested the age-related prediction of the Tropical Niche Conservatism hypothesis. We related the mean family age of angiosperm trees in 57 local forests from across China with 23 current and paleo-environmental variables, which included all major temperature- and precipitation-related variables. Our study shows that the mean family age of angiosperm trees in local forests was positively correlated with temperature and precipitation. This finding is consistent with the age-related prediction of the Tropical Niche Conservatism hypothesis. Approximately 85% of the variance in the mean family age of angiosperm trees was explained by temperature-related variables, and 81% of the variance in the mean family age of angiosperm trees was explained by precipitation-related variables. Climatic conditions at the Last Glacial Maximum did not explain additional variation in mean family age after accounting for current environmental conditions. PMID:27354109

  12. Ecological determinants of mean family age of angiosperm trees in forest communities in China.

    PubMed

    Qian, Hong; Chen, Shengbin

    2016-01-01

    Species assemblage in a local community is determined by the interplay of evolutionary and ecological processes. The Tropical Niche Conservatism hypothesis proposes mechanisms underlying patterns of biodiversity in biological communities along environmental gradients. This hypothesis predicts that, among other things, clades in areas with warm or wet environments are, on average, older than those in areas with cold or dry environments. Focusing on angiosperm trees in forests, this study tested the age-related prediction of the Tropical Niche Conservatism hypothesis. We related the mean family age of angiosperm trees in 57 local forests from across China with 23 current and paleo-environmental variables, which included all major temperature- and precipitation-related variables. Our study shows that the mean family age of angiosperm trees in local forests was positively correlated with temperature and precipitation. This finding is consistent with the age-related prediction of the Tropical Niche Conservatism hypothesis. Approximately 85% of the variance in the mean family age of angiosperm trees was explained by temperature-related variables, and 81% of the variance in the mean family age of angiosperm trees was explained by precipitation-related variables. Climatic conditions at the Last Glacial Maximum did not explain additional variation in mean family age after accounting for current environmental conditions. PMID:27354109

  13. Ecological determinants of mean family age of angiosperm trees in forest communities in China.

    PubMed

    Qian, Hong; Chen, Shengbin

    2016-06-29

    Species assemblage in a local community is determined by the interplay of evolutionary and ecological processes. The Tropical Niche Conservatism hypothesis proposes mechanisms underlying patterns of biodiversity in biological communities along environmental gradients. This hypothesis predicts that, among other things, clades in areas with warm or wet environments are, on average, older than those in areas with cold or dry environments. Focusing on angiosperm trees in forests, this study tested the age-related prediction of the Tropical Niche Conservatism hypothesis. We related the mean family age of angiosperm trees in 57 local forests from across China with 23 current and paleo-environmental variables, which included all major temperature- and precipitation-related variables. Our study shows that the mean family age of angiosperm trees in local forests was positively correlated with temperature and precipitation. This finding is consistent with the age-related prediction of the Tropical Niche Conservatism hypothesis. Approximately 85% of the variance in the mean family age of angiosperm trees was explained by temperature-related variables, and 81% of the variance in the mean family age of angiosperm trees was explained by precipitation-related variables. Climatic conditions at the Last Glacial Maximum did not explain additional variation in mean family age after accounting for current environmental conditions.

  14. Determining BMI cut points based on excess percent body fat in US children and adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current cut points for overweight were derived statistically from BMI distribution. The study aimed at determining age-, gender-, and ethnic-specific BMI cut points based on excess body fat in US children and adolescents aged 8-17 years, who participated in the National Health and Nutrition Examinat...

  15. On non-invasive 2D and 3D Chromatic White Light image sensors for age determination of latent fingerprints.

    PubMed

    Merkel, Ronny; Gruhn, Stefan; Dittmann, Jana; Vielhauer, Claus; Bräutigam, Anja

    2012-10-10

    The feasibility of 2D-intensity and 3D-topography images from a non-invasive Chromatic White Light (CWL) sensor for the age determination of latent fingerprints is investigated. The proposed method might provide the means to solve the so far unresolved issue of determining a fingerprints age in forensics. Conducting numerous experiments for an indoor crime scene using selected surfaces, different influences on the aging of fingerprints are investigated and the resulting aging variability is determined in terms of inter-person, intra-person, inter-finger and intra-finger variation. Main influence factors are shown to be the sweat composition, temperature, humidity, wind, UV-radiation, surface type, contamination of the finger with water-containing substances, resolution and measured area size, whereas contact time, contact pressure and smearing of the print seem to be of minor importance. Such influences lead to a certain experimental variability in inter-person and intra-person variation, which is higher than the inter-finger and intra-finger variation. Comparing the aging behavior of 17 different features using 1490 time series with a total of 41,520 fingerprint images, the great potential of the CWL technique in combination with the binary pixel feature from prior work is shown. Performing three different experiments for the classification of fingerprints into the two time classes [0, 5 h] and [5, 24 h], a maximum classification performance of 79.29% (kappa=0.46) is achieved for a general case, which is further improved for special cases. The statistical significance of the two best-performing features (both binary pixel versions based on 2D-intensity images) is manually shown and a feature fusion is performed, highlighting the strong dependency of the features on each other. It is concluded that such method might be combined with additional capturing devices, such as microscopes or spectroscopes, to a very promising age estimation scheme. PMID:22658793

  16. On non-invasive 2D and 3D Chromatic White Light image sensors for age determination of latent fingerprints.

    PubMed

    Merkel, Ronny; Gruhn, Stefan; Dittmann, Jana; Vielhauer, Claus; Bräutigam, Anja

    2012-10-10

    The feasibility of 2D-intensity and 3D-topography images from a non-invasive Chromatic White Light (CWL) sensor for the age determination of latent fingerprints is investigated. The proposed method might provide the means to solve the so far unresolved issue of determining a fingerprints age in forensics. Conducting numerous experiments for an indoor crime scene using selected surfaces, different influences on the aging of fingerprints are investigated and the resulting aging variability is determined in terms of inter-person, intra-person, inter-finger and intra-finger variation. Main influence factors are shown to be the sweat composition, temperature, humidity, wind, UV-radiation, surface type, contamination of the finger with water-containing substances, resolution and measured area size, whereas contact time, contact pressure and smearing of the print seem to be of minor importance. Such influences lead to a certain experimental variability in inter-person and intra-person variation, which is higher than the inter-finger and intra-finger variation. Comparing the aging behavior of 17 different features using 1490 time series with a total of 41,520 fingerprint images, the great potential of the CWL technique in combination with the binary pixel feature from prior work is shown. Performing three different experiments for the classification of fingerprints into the two time classes [0, 5 h] and [5, 24 h], a maximum classification performance of 79.29% (kappa=0.46) is achieved for a general case, which is further improved for special cases. The statistical significance of the two best-performing features (both binary pixel versions based on 2D-intensity images) is manually shown and a feature fusion is performed, highlighting the strong dependency of the features on each other. It is concluded that such method might be combined with additional capturing devices, such as microscopes or spectroscopes, to a very promising age estimation scheme.

  17. Towards a method for determining age ranges from faces of juveniles on photographs.

    PubMed

    Cummaudo, M; Guerzoni, M; Gibelli, D; Cigada, A; Obertovà, Z; Ratnayake, M; Poppa, P; Gabriel, P; Ritz-Timme, S; Cattaneo, C

    2014-06-01

    The steady increase in the distribution of juvenile pornographic material in recent years strongly required valid methods for estimating the age of the victims. At the present in fact forensic experts still commonly use the assessment of sexual characteristics by Tanner staging, although they have proven to be too subjective and deceiving for age estimation. The objective of this study, inspired by a previous EU project involving Italy, Germany and Lithuania, is to verify the applicability of certain anthropometric indices of faces in order to determine age and to create a database of facial measurements on a population of children in order to improve face ageing techniques. In this study, 1924 standardized facial images in frontal view and 1921 in lateral view of individuals from 7 age groups (3-5 years, 6-8 years, 9-11 years, 12-14 years, 15-17 years, 18-20 years, 21-24 years) underwent metric analysis. Individuals were all of Caucasoid ancestry and Italian nationality. Eighteen anthropometric indices in the frontal view and five in the lateral view were then calculated from the obtained measurements. Indices showing a correlation with age were ch-ch/ex-ex, ch-ch/pu-pu, en-en/ch-ch and se-sto/ex-ex in the frontal view, se-prn/se-sn, se-prn/se-sto and se-sn/se-sto in the lateral view. All the indices increased with age except for en-en/ch-ch, without relevant differences between males and females. These results provide an interesting starting point not only for placing a photographed face in an age range but also for refining the techniques of face ageing and personal identification. PMID:24726662

  18. Proteomic biomarkers for ageing the mosquito Aedes aegypti to determine risk of pathogen transmission.

    PubMed

    Hugo, Leon E; Monkman, James; Dave, Keyur A; Wockner, Leesa F; Birrell, Geoff W; Norris, Emma L; Kienzle, Vivian J; Sikulu, Maggy T; Ryan, Peter A; Gorman, Jeffery J; Kay, Brian H

    2013-01-01

    Biomarkers of the age of mosquitoes are required to determine the risk of transmission of various pathogens as each pathogen undergoes a period of extrinsic incubation in the mosquito host. Using the 2-D Difference Gel Electrophoresis (2-D DIGE) procedure, we investigated the abundance of up to 898 proteins from the Yellow Fever and dengue virus vector, Aedes aegypti, during ageing. By applying a mixed-effects model of protein expression, we identified five common patterns of abundance change during ageing and demonstrated an age-related decrease in variance for four of these. This supported a search for specific proteins with abundance changes that remain tightly associated with ageing for use as ageing biomarkers. Using MALDI-TOF/TOF mass spectrometry we identified ten candidate proteins that satisfied strict biomarker discovery criteria (identified in two out of three multivariate analysis procedures and in two cohorts of mosquitoes). We validated the abundances of the four most suitable candidates (Actin depolymerising factor; ADF, Eukaryotic initiation factor 5A; eIF5A, insect cuticle protein Q17LN8, and Anterior fat body protein; AFP) using semi-quantitative Western analysis of individual mosquitoes of six ages. The redox-response protein Manganese superoxide dismutase (SOD2) and electron shuttling protein Electron transfer oxidoreductase (ETO) were subject to post-translational modifications affecting their charge states with potential effects on function. For the four candidates we show remarkably consistent decreases in abundance during ageing, validating initial selections. In particular, the abundance of AFP is an ideal biomarker candidate for whether a female mosquito has lived long enough to be capable of dengue virus transmission. We have demonstrated proteins to be a suitable class of ageing biomarkers in mosquitoes and have identified candidates for epidemiological studies of dengue and the evaluation of new disease reduction projects targeting

  19. Proteomic Biomarkers for Ageing the Mosquito Aedes aegypti to Determine Risk of Pathogen Transmission

    PubMed Central

    Hugo, Leon E.; Monkman, James; Dave, Keyur A.; Wockner, Leesa F.; Birrell, Geoff W.; Norris, Emma L.; Kienzle, Vivian J.; Sikulu, Maggy T.; Ryan, Peter A.; Gorman, Jeffery J.; Kay, Brian H.

    2013-01-01

    Biomarkers of the age of mosquitoes are required to determine the risk of transmission of various pathogens as each pathogen undergoes a period of extrinsic incubation in the mosquito host. Using the 2-D Difference Gel Electrophoresis (2-D DIGE) procedure, we investigated the abundance of up to 898 proteins from the Yellow Fever and dengue virus vector, Aedes aegypti, during ageing. By applying a mixed-effects model of protein expression, we identified five common patterns of abundance change during ageing and demonstrated an age-related decrease in variance for four of these. This supported a search for specific proteins with abundance changes that remain tightly associated with ageing for use as ageing biomarkers. Using MALDI-TOF/TOF mass spectrometry we identified ten candidate proteins that satisfied strict biomarker discovery criteria (identified in two out of three multivariate analysis procedures and in two cohorts of mosquitoes). We validated the abundances of the four most suitable candidates (Actin depolymerising factor; ADF, Eukaryotic initiation factor 5A; eIF5A, insect cuticle protein Q17LN8, and Anterior fat body protein; AFP) using semi-quantitative Western analysis of individual mosquitoes of six ages. The redox-response protein Manganese superoxide dismutase (SOD2) and electron shuttling protein Electron transfer oxidoreductase (ETO) were subject to post-translational modifications affecting their charge states with potential effects on function. For the four candidates we show remarkably consistent decreases in abundance during ageing, validating initial selections. In particular, the abundance of AFP is an ideal biomarker candidate for whether a female mosquito has lived long enough to be capable of dengue virus transmission. We have demonstrated proteins to be a suitable class of ageing biomarkers in mosquitoes and have identified candidates for epidemiological studies of dengue and the evaluation of new disease reduction projects targeting

  20. Towards a method for determining age ranges from faces of juveniles on photographs.

    PubMed

    Cummaudo, M; Guerzoni, M; Gibelli, D; Cigada, A; Obertovà, Z; Ratnayake, M; Poppa, P; Gabriel, P; Ritz-Timme, S; Cattaneo, C

    2014-06-01

    The steady increase in the distribution of juvenile pornographic material in recent years strongly required valid methods for estimating the age of the victims. At the present in fact forensic experts still commonly use the assessment of sexual characteristics by Tanner staging, although they have proven to be too subjective and deceiving for age estimation. The objective of this study, inspired by a previous EU project involving Italy, Germany and Lithuania, is to verify the applicability of certain anthropometric indices of faces in order to determine age and to create a database of facial measurements on a population of children in order to improve face ageing techniques. In this study, 1924 standardized facial images in frontal view and 1921 in lateral view of individuals from 7 age groups (3-5 years, 6-8 years, 9-11 years, 12-14 years, 15-17 years, 18-20 years, 21-24 years) underwent metric analysis. Individuals were all of Caucasoid ancestry and Italian nationality. Eighteen anthropometric indices in the frontal view and five in the lateral view were then calculated from the obtained measurements. Indices showing a correlation with age were ch-ch/ex-ex, ch-ch/pu-pu, en-en/ch-ch and se-sto/ex-ex in the frontal view, se-prn/se-sn, se-prn/se-sto and se-sn/se-sto in the lateral view. All the indices increased with age except for en-en/ch-ch, without relevant differences between males and females. These results provide an interesting starting point not only for placing a photographed face in an age range but also for refining the techniques of face ageing and personal identification.

  1. Age determination and validation studies of marine fishes: do deep-dwellers live longer?

    PubMed

    Cailliet, G M; Andrews, A H; Burton, E J; Watters, D L; Kline, D E; Ferry-Graham, L A

    2001-04-01

    Age determination and validation studies on deep-water marine fishes indicate they are difficult to age and often long-lived. Techniques for the determination of age in individual fish includes growth-zone analysis of vertebral centra, fin rays and spines, other skeletal structures, and otoliths (there are three sets of otoliths in most bony fish semicircular canals, each of which is made of calcium carbonate). Most have regular increments deposited as the fish (and its semicircular canals) grows. The most commonly used otolith for age determination is the largest one called the sagitta. Age validation techniques include: (1) tag-recapture, often combined with oxytetracycline injection and analysis in growth-zones of bone upon recapture; (2) analysis of growth-zones over time; and (3) radiometric approaches utilizing a known radioactive decay series as an independent chronometer in otoliths from bony fishes. We briefly summarize previous studies using these three validation approaches and present results from several of our radiometric studies on deep-water, bony fishes recently subjected to expanding fisheries. Radiometric age validation results are presented for four species of scorpaenid fishes (the bank, Sebastes rufus, and bocaccio, S. paucispinis, rockfishes, and two thornyhead species, Sebastolobus altivelis and S. alascanus). In addition, our analysis of scorpaenids indicates that longevity increases exponentially with maximum depth of occurrence. The reason that the deep-water forms of scorpaenid fishes are long-lived is uncertain. Their longevity, however, may be related to altered physiological processes relative to environmental parameters like low temperature, high pressures, low light levels, low oxygen, and poor food resources.

  2. Attitudes about Aging and Gender among Young, Middle Age, and Older College-Based Students

    ERIC Educational Resources Information Center

    Laditka, Sarah B.; Fischer, Mary; Laditka, James N.; Segal, David R.

    2004-01-01

    Using an updated version of the Aging Semantic Differential, 534 younger, middle age, and older participants from a college community rated female and male targets categorized as ages 21-34 and 75-85. Participants also provided views about their own aging. Repeated measures of analysis of variance examined attitudinal differences by age and gender…

  3. Tritium-based age/streamflow relationships and catchment function

    NASA Astrophysics Data System (ADS)

    Stewart, M. K.; Morgenstern, U.

    2013-12-01

    Understanding runoff generation is important for management of freshwater systems. Determining transit time distributions (TTDs) of streamwaters and how they change with flow gives information on the flowpaths and water storages in catchments - fundamental for understanding the responses of streams to stressors such as pollution, land use change and climate change. This work uses tritium measurements on single samples to determine TTDs and how they change with flow. Such use of tritium is only practical so far in the Southern Hemisphere, because of its much-lower input of bomb-tritium in the 1960s. Another advantage of tritium is that it reveals the full spectrum of ages present in streams, whereas oxygen-18 or chloride variations only show younger ages (i.e. truncated TTDs). Case studies are presented for two New Zealand catchments, both with volcanic ash substrates. The first (Toenepi) is a dairy catchment near Hamilton, which shows well-constrained power law relationships between mean transit time (MTT) and flow, and between silica concentration and flow. Baseflow MTTs vary from 2.5 to 157 years. The second (Tutaeuaua) is a pastoral farming catchment near Taupo. Results for nested catchments along the stream also show power law relationships for both MTT and silica with flow. Baseflow MTTs vary from 1 to 11 years. Although the MTT data could be represented approximately by straight lines in log-log plots, hysteresis effects due to catchment wetness variations did disturb the relationships. Having TTDs from individual samples focusses attention on the nature of the water storages supplying the stream at the times of sampling. The flow record contains information on catchment function, which can enhance the value of the age data, provided such information can be satisfactorily interpreted. A new baseflow estimation method is used to determine the slow storage (aka groundwater) fraction in the stream. The age data is showing that slow storages have mean ages of

  4. Radiocarbon Based Ages and Growth Rates: Hawaiian Deep Sea Corals

    SciTech Connect

    Roark, E B; Guilderson, T P; Dunbar, R B; Ingram, B L

    2006-01-13

    The radial growth rates and ages of three different groups of Hawaiian deep-sea 'corals' were determined using radiocarbon measurements. Specimens of Corallium secundum, Gerardia sp., and Leiopathes glaberrima, were collected from 450 {+-} 40 m at the Makapuu deep-sea coral bed using a submersible (PISCES V). Specimens of Antipathes dichotoma were collected at 50 m off Lahaina, Maui. The primary source of carbon to the calcitic C. secundum skeleton is in situ dissolved inorganic carbon (DIC). Using bomb {sup 14}C time markers we calculate radial growth rates of {approx} 170 {micro}m y{sup -1} and ages of 68-75 years on specimens as tall as 28 cm of C. secundum. Gerardia sp., A. dichotoma, and L. glaberrima have proteinaceous skeletons and labile particulate organic carbon (POC) is their primary source of architectural carbon. Using {sup 14}C we calculate a radial growth rate of 15 {micro}m y{sup -1} and an age of 807 {+-} 30 years for a live collected Gerardia sp., showing that these organisms are extremely long lived. Inner and outer {sup 14}C measurements on four sub-fossil Gerardia spp. samples produce similar growth rate estimates (range 14-45 {micro}m y{sup -1}) and ages (range 450-2742 years) as observed for the live collected sample. Similarly, with a growth rate of < 10 {micro}m y{sup -1} and an age of {approx}2377 years, L. glaberrima at the Makapuu coral bed, is also extremely long lived. In contrast, the shallow-collected A. dichotoma samples yield growth rates ranging from 130 to 1,140 {micro}m y{sup -1}. These results show that Hawaiian deep-sea corals grow more slowly and are older than previously thought.

  5. Age determination of highly enriched uranium: separation and analysis of 231Pa.

    PubMed

    Morgenstern, A; Apostolidis, C; Mayer, K

    2002-11-01

    An analytical procedure has been developed for the age determination of highly enriched uranium samples exploiting the mother/daughter pair 235U/231Pa. Protactinium is separated from bulk uranium through highly selective sorption to silica gel and is subsequently quantified using alpha-spectrometry. The method has been validated using uranium standard reference materials of known ages. It affords decontamination factors exceeding 2.5 x 10(7), overall recoveries in the range of 80-85%, and a combined uncertainty below 5%.

  6. Age determination of highly enriched uranium: separation and analysis of 231Pa.

    PubMed

    Morgenstern, A; Apostolidis, C; Mayer, K

    2002-11-01

    An analytical procedure has been developed for the age determination of highly enriched uranium samples exploiting the mother/daughter pair 235U/231Pa. Protactinium is separated from bulk uranium through highly selective sorption to silica gel and is subsequently quantified using alpha-spectrometry. The method has been validated using uranium standard reference materials of known ages. It affords decontamination factors exceeding 2.5 x 10(7), overall recoveries in the range of 80-85%, and a combined uncertainty below 5%. PMID:12433081

  7. Direct Age Determination of a Subtropical Freshwater Crayfish (Redclaw, Cherax quadricarinatus) Using Ossicular Growth Marks

    PubMed Central

    Leland, Jesse C.; Bucher, Daniel J.; Coughran, Jason

    2015-01-01

    Recent studies have reported that crustacean age determination is possible. We applied a direct ageing method (i.e. transverse cross sectioning of gastric ossicles) to a subtropical freshwater crayfish (Cherax quadricarinatus) sourced from an aquaculture population. Growth mark periodicity and the potential for chronological depositions were investigated by staining C. quadricarinatus with calcein and examining their ossicles a year later. Pterocardiac ossicles were superior to other ageing structures (i.e. other ossicles and eyestalks) and produced repeatable between-reader counts (87% were corroborated and 13% varied by ±1). C. quadricarinatus size-at-age data (for an aquaculture population) was described by a von Bertalanffy growth equation (L∞ = 32 mm occipital carapace length; K = 0.64; t0 = –0.18; R2 = 0.81). Ossicular growth marks did not correspond to moult history. The calcein stain was retained over an annual cycle comprising multiple moults, demonstrating that pterocardiac ossicles retain chronological information. The maximum age (3+) corroborated other indirectly-obtained longevity estimates for C. quadricarinatus. Multiple lines of evidence indicate that the growth marks in C. quadricarinatus ossicles are probably deposited annually during winter. The ability to extract age information from subtropical decapods provides substantial opportunities for advancing fisheries and conservation research globally, but further research is needed to provide a definitive validation and elucidate the mechanism governing the accrual of ossicular growth marks. PMID:26309228

  8. Ar-40-Ar-39 and Rb-Sr age determinations on Quaternary volcanic rocks

    NASA Technical Reports Server (NTRS)

    Radicati Di Brozolo, F.; Huneke, J. C.; Papanastassiou, D. A.; Wasserburg, G. J.

    1981-01-01

    Ages of leucite and biotite separates from samples of the potassic volcanics of the Roman Comagmatic region are derived by the stepwise degassing variant of the Ar-39-Ar-40 dating method and compared with those derived from Rb-Sr dating in order to evaluate the abilities of the methods to date Quaternary geological events. Six of the leucite separates are found to contain Ar with very high bulk 40/36 ratios and to have well correlated Ar-40 and Ar-39 contents, yielding ages of approximately 338,000 years. Two leucites observed to contain Ar with lower bulk 40/36 ratios and Ar-40/Ar-36 ratios significantly lower than atmospheric are found to have ages in substantial agreement with those of the other leucites despite the uncertainty in the composition of the trapped component. Ages obtained for the biotites are not as precise as those of the leucites, due to difficulties in obtaining a good separation of in situ radiogenic Ar-40 from trapped Ar-40. Ages determined from Rb-Sr measurements for selected tuff samples are found to be in good agreement with the Ar-40-Ar-39 ages of the leucites. Results demonstrate the possibility of attaining precisions of better than 5% in the dating of rocks 350,000 years old by both the Ar-40-Ar-39 and the Rb-Sr methods.

  9. What determines age-related disease: do we know all the right questions?

    PubMed Central

    2009-01-01

    The average human lifespan has increased throughout the last century due to the mitigation of many infectious diseases. More people now die of age-related diseases than ever before, but these diseases have been resistant to elimination. Progress has been made in treatments and preventative measures to delay the onsets of these diseases, but most cancers and vascular diseases are still with us and they kill about the same fraction of the population year after year. For example, US Caucasian female deaths from breast plus genital cancers have remained a fairly constant ~7% of the age-related disease deaths from 1938 to 1998 and have been consistently ~2-fold greater than female colon plus rectal cancer deaths over that span. This type of stability pattern pervades the age-related diseases and suggests that intrinsic properties within populations determine these fractions. Recognizing this pattern and deciphering its origin will be necessary for the complete understanding of these major causes of death. It would appear that more than the random processes of aging drive this effect. The question is how to meaningfully approach this problem. This commentary discusses the epidemiological and aging perspectives and their current limitations in providing an explanation. The age of bioinformatics offers hope, but only if creative systems approaches are forthcoming. PMID:19904627

  10. Direct Age Determination of a Subtropical Freshwater Crayfish (Redclaw, Cherax quadricarinatus) Using Ossicular Growth Marks.

    PubMed

    Leland, Jesse C; Bucher, Daniel J; Coughran, Jason

    2015-01-01

    Recent studies have reported that crustacean age determination is possible. We applied a direct ageing method (i.e. transverse cross sectioning of gastric ossicles) to a subtropical freshwater crayfish (Cherax quadricarinatus) sourced from an aquaculture population. Growth mark periodicity and the potential for chronological depositions were investigated by staining C. quadricarinatus with calcein and examining their ossicles a year later. Pterocardiac ossicles were superior to other ageing structures (i.e. other ossicles and eyestalks) and produced repeatable between-reader counts (87% were corroborated and 13% varied by ±1). C. quadricarinatus size-at-age data (for an aquaculture population) was described by a von Bertalanffy growth equation (L∞ = 32 mm occipital carapace length; K = 0.64; t0 = -0.18; R2 = 0.81). Ossicular growth marks did not correspond to moult history. The calcein stain was retained over an annual cycle comprising multiple moults, demonstrating that pterocardiac ossicles retain chronological information. The maximum age (3+) corroborated other indirectly-obtained longevity estimates for C. quadricarinatus. Multiple lines of evidence indicate that the growth marks in C. quadricarinatus ossicles are probably deposited annually during winter. The ability to extract age information from subtropical decapods provides substantial opportunities for advancing fisheries and conservation research globally, but further research is needed to provide a definitive validation and elucidate the mechanism governing the accrual of ossicular growth marks. PMID:26309228

  11. Individual Differences in Exercise Behavior: Stability and Change in Genetic and Environmental Determinants From Age 7 to 18.

    PubMed

    Huppertz, Charlotte; Bartels, Meike; de Zeeuw, Eveline L; van Beijsterveldt, Catharina E M; Hudziak, James J; Willemsen, Gonneke; Boomsma, Dorret I; de Geus, Eco J C

    2016-09-01

    Exercise behavior during leisure time is a major source of health-promoting physical activity and moderately tracks across childhood and adolescence. This study aims to investigate the absolute and relative contribution of genes and the environment to variance in exercise behavior from age 7 to 18, and to elucidate the stability and change of genetic and shared environmental factors that underlie this behavior. The Netherlands Twin Register collected data on exercise behavior in twins aged approximately 7, 10, 12, 14, 16 and 18 years (N = 27,332 twins; 48 % males; 47 % with longitudinal assessments). Three exercise categories (low, middle, high) were analyzed by means of liability threshold models. First, a univariate model was fitted using the largest available cross-sectional dataset with linear and quadratic effects of age as modifiers on the means and variance components. Second, a simplex model was fitted on the longitudinal dataset. Heritability was low in 7-year-olds (14 % in males and 12 % in females), but gradually increased up to age 18 (79 % in males and 49 % in females), whereas the initially substantial relative influence of the shared environment decreased with age (from 80 to 4 % in males and from 80 to 19 % in females). This decrease was due to a large increase in the genetic variance. The longitudinal model showed the genetic effects in males to be largely stable and to accumulate from childhood to late adolescence, whereas in females, they were marked by both transmission and innovation at all ages. The shared environmental effects tended to be less stable in both males and females. In sum, the clear age-moderation of exercise behavior implies that family-based interventions might be useful to increase this behavior in children, whereas individual-based interventions might be better suited for adolescents. We showed that some determinants of individual differences in exercise behavior are stable across childhood and youth, whereas

  12. Effects of aging on strategic-based visuomotor learning.

    PubMed

    Alfonso Uresti-Cabrera, Luis; Vaca-Palomares, Israel; Diaz, Rosalinda; Beltran-Parrazal, Luis; Fernandez-Ruiz, Juan

    2015-08-27

    There are different kinds of visuomotor learnings. One of the most studied is error-based learning where the information about the sign and magnitude of the error is used to update the motor commands. However, there are other instances where subjects show visuomotor learning even if the use of error sign and magnitude information is precluded. In those instances subjects could be using strategic instead of procedural adaptation mechanisms. Here, we present the results of the effect of aging on visuomotor strategic learning under a reversed error feedback condition, and its contrast with procedural visuomotor learning within the same participants. A number of measures were obtained from a task consisting of throwing clay balls to a target before, during and after wearing lateral displacing or reversing prisms. The displacing prism results show an age dependent decrease on the learning rate that corroborates previous findings. The reversing prism results also show significant adaptation impairment in the aged population. However, decreased reversing learning in the older group was the result of an increase in the number of subjects that could not adapt to the reversing prism, and not on a reduction of the learning capacity of all the individuals of the group. These results suggest a significant deleterious effect of aging on visuomotor strategic learning implementation. PMID:26014620

  13. Effects of aging on strategic-based visuomotor learning.

    PubMed

    Alfonso Uresti-Cabrera, Luis; Vaca-Palomares, Israel; Diaz, Rosalinda; Beltran-Parrazal, Luis; Fernandez-Ruiz, Juan

    2015-08-27

    There are different kinds of visuomotor learnings. One of the most studied is error-based learning where the information about the sign and magnitude of the error is used to update the motor commands. However, there are other instances where subjects show visuomotor learning even if the use of error sign and magnitude information is precluded. In those instances subjects could be using strategic instead of procedural adaptation mechanisms. Here, we present the results of the effect of aging on visuomotor strategic learning under a reversed error feedback condition, and its contrast with procedural visuomotor learning within the same participants. A number of measures were obtained from a task consisting of throwing clay balls to a target before, during and after wearing lateral displacing or reversing prisms. The displacing prism results show an age dependent decrease on the learning rate that corroborates previous findings. The reversing prism results also show significant adaptation impairment in the aged population. However, decreased reversing learning in the older group was the result of an increase in the number of subjects that could not adapt to the reversing prism, and not on a reduction of the learning capacity of all the individuals of the group. These results suggest a significant deleterious effect of aging on visuomotor strategic learning implementation.

  14. Application of skeletal age based on x-ray in selecting sports talents

    NASA Astrophysics Data System (ADS)

    Mao, Zongzhen; Xu, Guodong; Song, Tao

    2012-01-01

    Skeletal age has been studied and proved that for most elite athletes, it was coincident with the chronological ages when they were young. In order to explore the application of skeletal age in selecting sports talent, 32 athletes (female, chronological age 5-12 y) were chosen from the Gymnastics Training Base in this study. Their left hand-wrists were photographed with X-rays, and then the skeletal ages were estimated by Chinese version of the Tanner-Whitehouse Skeletal Maturity Assessment System. At the same time, their body shapes, functions, and sports ability were also measured. Results showed that 71.88% of the skeletal age was proportional to their chronological age (+/- 1 y); while 18.75% of the skeletal maturity was retarded by 1- 2 year, 9.37% of those was advanced more than 1 year. On the other hand, the body shape, functions and sports ability of the athletes were positively related with their skeletal maturity. This study proved that the determination of skeletal maturity is a reliable evaluation for selecting sports talent. A further study on the influence of gymnastics on the skeletal age is of great significance.

  15. Improved age determination of blood and teeth samples using a selected set of DNA methylation markers

    PubMed Central

    Kamalandua, Aubeline

    2015-01-01

    Age estimation from DNA methylation markers has seen an exponential growth of interest, not in the least from forensic scientists. The current published assays, however, can still be improved by lowering the number of markers in the assay and by providing more accurate models to predict chronological age. From the published literature we selected 4 age-associated genes (ASPA, PDE4C, ELOVL2, and EDARADD) and determined CpG methylation levels from 206 blood samples of both deceased and living individuals (age range: 0–91 years). This data was subsequently used to compare prediction accuracy with both linear and non-linear regression models. A quadratic regression model in which the methylation levels of ELOVL2 were squared showed the highest accuracy with a Mean Absolute Deviation (MAD) between chronological age and predicted age of 3.75 years and an adjusted R2 of 0.95. No difference in accuracy was observed for samples obtained either from living and deceased individuals or between the 2 genders. In addition, 29 teeth from different individuals (age range: 19–70 years) were analyzed using the same set of markers resulting in a MAD of 4.86 years and an adjusted R2 of 0.74. Cross validation of the results obtained from blood samples demonstrated the robustness and reproducibility of the assay. In conclusion, the set of 4 CpG DNA methylation markers is capable of producing highly accurate age predictions for blood samples from deceased and living individuals PMID:26280308

  16. 5 CFR 1650.41 - How to obtain an age-based withdrawal.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false How to obtain an age-based withdrawal... an age-based withdrawal. To request an age-based withdrawal, a participant must submit to the TSP record keeper a properly completed paper TSP age-based withdrawal request form or use the TSP Web site...

  17. 5 CFR 1650.41 - How to obtain an age-based withdrawal.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false How to obtain an age-based withdrawal... an age-based withdrawal. To request an age-based withdrawal, a participant must submit to the TSP record keeper a properly completed paper TSP age-based withdrawal request form or use the TSP Web site...

  18. 5 CFR 1650.41 - How to obtain an age-based withdrawal.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false How to obtain an age-based withdrawal... an age-based withdrawal. To request an age-based withdrawal, a participant must submit to the TSP record keeper a properly completed paper TSP age-based withdrawal request form or use the TSP Web site...

  19. Socioeconomic determinants of iron-deficiency anemia among children aged 6 to 59 months in India.

    PubMed

    Bharati, Susmita; Pal, Manoranjan; Chakrabarty, Suman; Bharati, Premananda

    2015-03-01

    The extent of anemia and its socioeconomic determinants among the preschool children (6-59 months old) in India have been studied in this article. Relevant data are taken from the third round of the National Family Health Survey. The initial analysis reveals some interesting features. The most affected children are in the age-group of 6 to 23 months. Beyond this age a decreasing trend is observed up to the age of 48 to 59 months. The highest and the lowest prevalence of anemia have been found to be in the central and the northeast zones, respectively. The vulnerable groups are the children of illiterate parents and those belonging to the poor families in the rural areas. Categorical logistic regression also confirms that status of literacy and wealth of parents have strong negative association with the status of anemia of the children.

  20. Socioeconomic status overrides age and gender in determining health-seeking behaviour in rural Bangladesh.

    PubMed Central

    Ahmed, Syed Masud; Tomson, Göran; Petzold, Max; Kabir, Zarina Nahar

    2005-01-01

    OBJECTIVE: To study the health-seeking behaviour of elderly members (aged > 60 years) of households in rural Bangladesh, to ascertain how their behaviour differs from that of younger people (aged 20-59 years) living in the same household and to explore the determinants of health-seeking behaviour. METHODS: Structured interviews were conducted to elicit information on the health-seeking behaviour of household members aged > 20 years. Respondents were asked about major illnesses occurring within 15 days prior to the interview. The sample consisted of 966 households that had at least one resident who was aged > 60 (32% of 3031 households). FINDINGS: We found no major differences in health-seeking behaviour between elderly people and younger adults. On average about 35% (405/1169) of those who reported having been ill during the previous 15 days in both age groups chose self-care/self-treatment; for both age groups the most commonly consulted type of provider was a paraprofessional such as a village doctor, a medical assistant or a community health worker. A household's poverty status emerged as a major determinant of health-seeking behaviour. The odds ratio (OR) that individuals from poor households would seek treatment from unqualified allopathic practitioners was 0.6 (95% confidence interval (CI) = 0.40-0.78); the odds ratio that individuals from poor households would seek treatment from qualified allopathic practitioners was 0.7 (95% CI = 0.60-0.95). For self-care or self-treatment it was 1.8 (95% CI = 1.43-2.36). Patients' level of education affected whether they avoided self-care/self-treatment and drugstore salespeople (who are usually unlicensed and untrained but who diagnose illnesses and sell medicine) and instead chose a formal allopathic practitioner (OR = 1.5; 95% CI = 1.15-1.96). When a household's poverty status was controlled for, there were no differences in age or gender in terms of health-care expenditure. CONCLUSION: We found that socioeconomic

  1. Effects of age, replicative lifespan and growth rate of human nucleus pulposus cells on selecting age range for cell-based biological therapies for degenerative disc diseases.

    PubMed

    Lee, J S; Lee, S M; Jeong, S W; Sung, Y G; Lee, J H; Kim, K W

    2016-07-01

    Autologous disc cell implantation, growth factors and gene therapy appear to be promising therapies for disc regeneration. Unfortunately, the replicative lifespan and growth kinetics of human nucleus pulposus (NP) cells related to host age are unclear. We investigated the potential relations among age, replicative lifespan and growth rate of NP cells, and determined the age range that is suitable for cell-based biological therapies for degenerative disc diseases. We used NP tissues classified by decade into five age groups: 30s, 40s, 50s, 60s and 70s. The mean cumulative population doubling level (PDL) and population doubling rate (PDR) of NP cells were assessed by decade. We also investigated correlations between cumulative PDL and age, and between PDR and age. The mean cumulative PDL and PDR decreased significantly in patients in their 60s. The mean cumulative PDL and PDR in the younger groups (30s, 40s and 50s) were significantly higher than those in the older groups (60s and 70s). There also were significant negative correlations between cumulative PDL and age, and between PDR and age. We found that the replicative lifespan and growth rate of human NP cells decreased with age. The replicative potential of NP cells decreased significantly in patients 60 years old and older. Young individuals less than 60 years old may be suitable candidates for NP cell-based biological therapies for treating degenerative disc diseases.

  2. Reliability-based lifetime maintenance of aging highway bridges

    NASA Astrophysics Data System (ADS)

    Enright, Michael P.; Frangopol, Dan M.

    2000-06-01

    As the nation's infrastructure continues to age, the cost of maintaining it at an acceptable safety level continues to increase. In the United States, about one of every three bridges is rated structurally deficient and/or functionally obsolete. It will require about 80 billion to eliminate the current backlog of bridge deficiencies and maintain repair levels. Unfortunately, the financial resources allocated for these activities fall extremely short of the demand. Although several existing and emerging NDT techniques are available to gather inspection data, current maintenance planning decisions for deficient bridges are based on data from subjective condition assessments and do not consider the reliability of bridge components and systems. Recently, reliability-based optimum maintenance planning strategies have been developed. They can be used to predict inspection and repair times to achieve minimum life-cycle cost of deteriorating structural systems. In this study, a reliability-based methodology which takes into account loading randomness and history, and randomness in strength and degradation resulting from aggressive environmental factors, is used to predict the time- dependent reliability of aging highway bridges. A methodology for incorporating inspection data into reliability predictions is also presented. Finally, optimal lifetime maintenance strategies are identified, in which optimal inspection/repair times are found based on minimum expected life-cycle cost under prescribed reliability constraints. The influence of discount rate on optimum solutions is evaluated.

  3. Electroencephalogram-based methodology for determining unconsciousness during depopulation.

    PubMed

    Benson, E R; Alphin, R L; Rankin, M K; Caputo, M P; Johnson, A L

    2012-12-01

    When an avian influenza or virulent Newcastle disease outbreak occurs within commercial poultry, key steps involved in managing a fast-moving poultry disease can include: education; biosecurity; diagnostics and surveillance; quarantine; elimination of infected poultry through depopulation or culling, disposal, and disinfection; and decreasing host susceptibility. Available mass emergency depopulation procedures include whole-house gassing, partial-house gassing, containerized gassing, and water-based foam. To evaluate potential depopulation methods, it is often necessary to determine the time to the loss of consciousness (LOC) in poultry. Many current approaches to evaluating LOC are qualitative and require visual observation of the birds. This study outlines an electroencephalogram (EEG) frequency domain-based approach for determining the point at which a bird loses consciousness. In this study, commercial broilers were used to develop the methodology, and the methodology was validated with layer hens. In total, 42 data sets from 13 broilers aged 5-10 wk and 12 data sets from four spent hens (age greater than 1 yr) were collected and analyzed. A wireless EEG transmitter was surgically implanted, and each bird was monitored during individual treatment with isoflurane anesthesia. EEG data were evaluated using a frequency-based approach. The alpha/delta (A/D, alpha: 8-12 Hz, delta: 0.5-4 Hz) ratio and loss of posture (LOP) were used to determine the point at which the birds became unconscious. Unconsciousness, regardless of the method of induction, causes suppression in alpha and a rise in the delta frequency component, and this change is used to determine unconsciousness. There was no statistically significant difference between time to unconsciousness as measured by A/D ratio or LOP, and the A/D values were correlated at the times of unconsciousness. The correlation between LOP and A/D ratio indicates that the methodology is appropriate for determining

  4. Disentangling the genetic determinants of human aging: biological age as an alternative to the use of survival measures.

    PubMed

    Karasik, David; Demissie, Serkalem; Cupples, L Adrienne; Kiel, Douglas P

    2005-05-01

    The choice of a phenotype is critical for the study of a complex genetically regulated process, such as aging. To date, most of the twin and family studies have focused on broad survival measures, primarily age at death or exceptional longevity. However, on the basis of recent studies of twins and families, biological age has also been shown to have a strong genetic component, with heritability estimates ranging from 27% to 57%. The aim of this review is twofold: first, to summarize growing consensus on reliable methods of biological age assessment, and second, to demonstrate validity of this phenotype for research in the genetics of aging in humans.

  5. Age determinations in the Precambrian basement of the Wadi Araba area, southwest Jordan

    NASA Astrophysics Data System (ADS)

    Jarrar, Ghaleb; Baumann, Albrecht; Wachendorf, Horst

    1983-05-01

    The Precambrian basement of Jordan belongs to the northern margin of the Arabian-Nubian Shield. Age determinations by U-Pb isotopic analyses on sized and magnetic zircon fractions, a monazite and an apatite sample and by Rb-Sr isotopic studies on whole-rocks and minerals of metasedimentary rocks, granodiorites, granites and dykes have elucidated the following events: (1)A major regional high-grade metamorphism accompanied by migmatization and synkinematic plutonism occurred at about 800 Ma according to U-Pb zircon ages of metasediments and granites. (2)During a postkinematic plutonic event between 615 and 600 Ma extensive masses of granodioritic to granitic composition and dykes were emplaced. The U-Pb data of zircons of the rocks yielded upper intercept ages with the concordia consistent with Rb-Sr biotite ages. The Rb-Sr mineral ages of the older metasedimentary rocks document the resetting of the Rb-Sr system due to the thermal pulse at this time. (3)A younger plutonic event produced diorites and dykes at about 570 Ma. The plutonic events are related to the Pan-African orogenic phase. The low initial 87Sr/ 86Sr ratios of the plutonic rocks (0.7032-0.7046) correspond to values reported from equivalent rocks throughout the Arabian-Nubian Shield and suggest that no significant portions of ancient sialic crustal material contributed to the generation of the granitic to granodioritic magmas.

  6. Fetal kidney length as a useful adjunct parameter for better determination of gestational age

    PubMed Central

    Ugur, Mete G.; Mustafa, Aynur; Ozcan, Huseyin C.; Tepe, Neslihan B.; Kurt, Huseyin; Akcil, Emre; Gunduz, Reyhan

    2016-01-01

    Objectives: To determine the validity of fetal kidney length and amniotic fluid index (AFI) in labor dating. Methods: This prospective study included 180 pregnant women followed up in the outpatient clinic at the Department of Obstetrics and Gynecology, Gaziantep University, Turkey, between January 2014 and January 2015. The gestational age (GA) was estimated by early fetal ultrasound measures and last menstrual period. Routine fetal biometric parameters, fetal kidney length, and amniotic fluid index were measured. We studied the correlation between fetal kidney length, amniotic fluid index, and gestational age. Result: The mean gestational age depending on last menstrual period and early ultrasound was 31.98±4.29 (24-39 weeks). The mean kidney length was 35.66±6.61 (19-49 mm). There was a significant correlation between gestational age and fetal kidney length (r=0.947, p=0.001). However, there was a moderate negative correlation between GA and AFI. Adding fetal kidney length to the routine biometrics improved the effectiveness of the model used to estimate GA (R2=0.965 to R2=0.987). Conclusion: Gestational age can be better predicted by adding fetal kidney length to other routine parameters. PMID:27146616

  7. Age affects chunk-based, but not rule-based learning in artificial grammar acquisition.

    PubMed

    Kürten, Julia; De Vries, Meinou H; Kowal, Kristina; Zwitserlood, Pienie; Flöel, Agnes

    2012-07-01

    Explicit learning is well known to decline with age, but divergent results have been reported for implicit learning. Here, we assessed the effect of aging on implicit vs. explicit learning within the same task. Fifty-five young (mean 32 years) and 55 elderly (mean 64 years) individuals were exposed to letter strings generated by an artificial grammar. Subsequently, participants classified novel strings as grammatical or nongrammatical. Acquisition of superficial ("chunk-based") and structural ("rule-based") features of the grammar were analyzed separately. We found that overall classification accuracy was diminished in the elderly, driven by decreased performance on items that required chunk-based knowledge. Performance on items requiring rule-based knowledge was comparable between groups. Results indicate that rule-based and chunk-based learning are differentially affected by age: while rule-based learning, reflecting implicit learning, is preserved, chunk-based learning, which contains at least some explicit learning aspects, declines with age. Our findings may explain divergent results on implicit learning tasks in previous studies on aging. They may also help to better understand compensatory mechanisms during the aging process.

  8. CAG repeat expansion in Huntington disease determines age at onset in a fully dominant fashion

    PubMed Central

    Lee, J.-M.; Ramos, E.M.; Lee, J.-H.; Gillis, T.; Mysore, J.S.; Hayden, M.R.; Warby, S.C.; Morrison, P.; Nance, M.; Ross, C.A.; Margolis, R.L.; Squitieri, F.; Orobello, S.; Di Donato, S.; Gomez-Tortosa, E.; Ayuso, C.; Suchowersky, O.; Trent, R.J.A.; McCusker, E.; Novelletto, A.; Frontali, M.; Jones, R.; Ashizawa, T.; Frank, S.; Saint-Hilaire, M.H.; Hersch, S.M.; Rosas, H.D.; Lucente, D.; Harrison, M.B.; Zanko, A.; Abramson, R.K.; Marder, K.; Sequeiros, J.; Paulsen, J.S.; Landwehrmeyer, G.B.; Myers, R.H.; MacDonald, M.E.; Durr, Alexandra; Rosenblatt, Adam; Frati, Luigi; Perlman, Susan; Conneally, Patrick M.; Klimek, Mary Lou; Diggin, Melissa; Hadzi, Tiffany; Duckett, Ayana; Ahmed, Anwar; Allen, Paul; Ames, David; Anderson, Christine; Anderson, Karla; Anderson, Karen; Andrews, Thomasin; Ashburner, John; Axelson, Eric; Aylward, Elizabeth; Barker, Roger A.; Barth, Katrin; Barton, Stacey; Baynes, Kathleen; Bea, Alexandra; Beall, Erik; Beg, Mirza Faisal; Beglinger, Leigh J.; Biglan, Kevin; Bjork, Kristine; Blanchard, Steve; Bockholt, Jeremy; Bommu, Sudharshan Reddy; Brossman, Bradley; Burrows, Maggie; Calhoun, Vince; Carlozzi, Noelle; Chesire, Amy; Chiu, Edmond; Chua, Phyllis; Connell, R.J.; Connor, Carmela; Corey-Bloom, Jody; Craufurd, David; Cross, Stephen; Cysique, Lucette; Santos, Rachelle Dar; Davis, Jennifer; Decolongon, Joji; DiPietro, Anna; Doucette, Nicholas; Downing, Nancy; Dudler, Ann; Dunn, Steve; Ecker, Daniel; Epping, Eric A.; Erickson, Diane; Erwin, Cheryl; Evans, Ken; Factor, Stewart A.; Farias, Sarah; Fatas, Marta; Fiedorowicz, Jess; Fullam, Ruth; Furtado, Sarah; Garde, Monica Bascunana; Gehl, Carissa; Geschwind, Michael D.; Goh, Anita; Gooblar, Jon; Goodman, Anna; Griffith, Jane; Groves, Mark; Guttman, Mark; Hamilton, Joanne; Harrington, Deborah; Harris, Greg; Heaton, Robert K.; Helmer, Karl; Henneberry, Machelle; Hershey, Tamara; Herwig, Kelly; Howard, Elizabeth; Hunter, Christine; Jankovic, Joseph; Johnson, Hans; Johnson, Arik; Jones, Kathy; Juhl, Andrew; Kim, Eun Young; Kimble, Mycah; King, Pamela; Klimek, Mary Lou; Klöppel, Stefan; Koenig, Katherine; Komiti, Angela; Kumar, Rajeev; Langbehn, Douglas; Leavitt, Blair; Leserman, Anne; Lim, Kelvin; Lipe, Hillary; Lowe, Mark; Magnotta, Vincent A.; Mallonee, William M.; Mans, Nicole; Marietta, Jacquie; Marshall, Frederick; Martin, Wayne; Mason, Sarah; Matheson, Kirsty; Matson, Wayne; Mazzoni, Pietro; McDowell, William; Miedzybrodzka, Zosia; Miller, Michael; Mills, James; Miracle, Dawn; Montross, Kelsey; Moore, David; Mori, Sasumu; Moser, David J.; Moskowitz, Carol; Newman, Emily; Nopoulos, Peg; Novak, Marianne; O'Rourke, Justin; Oakes, David; Ondo, William; Orth, Michael; Panegyres, Peter; Pease, Karen; Perlman, Susan; Perlmutter, Joel; Peterson, Asa; Phillips, Michael; Pierson, Ron; Potkin, Steve; Preston, Joy; Quaid, Kimberly; Radtke, Dawn; Rae, Daniela; Rao, Stephen; Raymond, Lynn; Reading, Sarah; Ready, Rebecca; Reece, Christine; Reilmann, Ralf; Reynolds, Norm; Richardson, Kylie; Rickards, Hugh; Ro, Eunyoe; Robinson, Robert; Rodnitzky, Robert; Rogers, Ben; Rosenblatt, Adam; Rosser, Elisabeth; Rosser, Anne; Price, Kathy; Price, Kathy; Ryan, Pat; Salmon, David; Samii, Ali; Schumacher, Jamy; Schumacher, Jessica; Sendon, Jose Luis Lópenz; Shear, Paula; Sheinberg, Alanna; Shpritz, Barnett; Siedlecki, Karen; Simpson, Sheila A.; Singer, Adam; Smith, Jim; Smith, Megan; Smith, Glenn; Snyder, Pete; Song, Allen; Sran, Satwinder; Stephan, Klaas; Stober, Janice; Sü?muth, Sigurd; Suter, Greg; Tabrizi, Sarah; Tempkin, Terry; Testa, Claudia; Thompson, Sean; Thomsen, Teri; Thumma, Kelli; Toga, Arthur; Trautmann, Sonja; Tremont, Geoff; Turner, Jessica; Uc, Ergun; Vaccarino, Anthony; van Duijn, Eric; Van Walsem, Marleen; Vik, Stacie; Vonsattel, Jean Paul; Vuletich, Elizabeth; Warner, Tom; Wasserman, Paula; Wassink, Thomas; Waterman, Elijah; Weaver, Kurt; Weir, David; Welsh, Claire; Werling-Witkoske, Chris; Wesson, Melissa; Westervelt, Holly; Weydt, Patrick; Wheelock, Vicki; Williams, Kent; Williams, Janet; Wodarski, Mary; Wojcieszek, Joanne; Wood, Jessica; Wood-Siverio, Cathy; Wu, Shuhua; Yastrubetskaya, Olga; de Yebenes, Justo Garcia; Zhao, Yong Qiang; Zimbelman, Janice; Zschiegner, Roland; Aaserud, Olaf; Abbruzzese, Giovanni; Andrews, Thomasin; Andrich, Jurgin; Antczak, Jakub; Arran, Natalie; Artiga, Maria J. Saiz; Bachoud-Lévi, Anne-Catherine; Banaszkiewicz, Krysztof; di Poggio, Monica Bandettini; Bandmann, Oliver; Barbera, Miguel A.; Barker, Roger A.; Barrero, Francisco; Barth, Katrin; Bas, Jordi; Beister, Antoine; Bentivoglio, Anna Rita; Bertini, Elisabetta; Biunno, Ida; Bjørgo, Kathrine; Bjørnevoll, Inga; Bohlen, Stefan; Bonelli, Raphael M.; Bos, Reineke; Bourne, Colin; Bradbury, Alyson; Brockie, Peter; Brown, Felicity; Bruno, Stefania; Bryl, Anna; Buck, Andrea; Burg, Sabrina; Burgunder, Jean-Marc; Burns, Peter; Burrows, Liz; Busquets, Nuria; Busse, Monica; Calopa, Matilde; Carruesco, Gemma T.; Casado, Ana Gonzalez; Catena, Judit López; Chu, Carol; Ciesielska, Anna; Clapton, Jackie; Clayton, Carole; Clenaghan, Catherine; Coelho, Miguel; Connemann, Julia; Craufurd, David; Crooks, Jenny; Cubillo, Patricia Trigo; Cubo, Esther; Curtis, Adrienne; De Michele, Giuseppe; De Nicola, A.; de Souza, Jenny; de Weert, A. Marit; de Yébenes, Justo Garcia; Dekker, M.; Descals, A. Martínez; Di Maio, Luigi; Di Pietro, Anna; Dipple, Heather; Dose, Matthias; Dumas, Eve M.; Dunnett, Stephen; Ecker, Daniel; Elifani, F.; Ellison-Rose, Lynda; Elorza, Marina D.; Eschenbach, Carolin; Evans, Carole; Fairtlough, Helen; Fannemel, Madelein; Fasano, Alfonso; Fenollar, Maria; Ferrandes, Giovanna; Ferreira, Jaoquim J.; Fillingham, Kay; Finisterra, Ana Maria; Fisher, K.; Fletcher, Amy; Foster, Jillian; Foustanos, Isabella; Frech, Fernando A.; Fullam, Robert; Fullham, Ruth; Gago, Miguel; García, RocioGarcía-Ramos; García, Socorro S.; Garrett, Carolina; Gellera, Cinzia; Gill, Paul; Ginestroni, Andrea; Golding, Charlotte; Goodman, Anna; Gørvell, Per; Grant, Janet; Griguoli, A.; Gross, Diana; Guedes, Leonor; BascuñanaGuerra, Monica; Guerra, Maria Rosalia; Guerrero, Rosa; Guia, Dolores B.; Guidubaldi, Arianna; Hallam, Caroline; Hamer, Stephanie; Hammer, Kathrin; Handley, Olivia J.; Harding, Alison; Hasholt, Lis; Hedge, Reikha; Heiberg, Arvid; Heinicke, Walburgis; Held, Christine; Hernanz, Laura Casas; Herranhof, Briggitte; Herrera, Carmen Durán; Hidding, Ute; Hiivola, Heli; Hill, Susan; Hjermind, Lena. E.; Hobson, Emma; Hoffmann, Rainer; Holl, Anna Hödl; Howard, Liz; Hunt, Sarah; Huson, Susan; Ialongo, Tamara; Idiago, Jesus Miguel R.; Illmann, Torsten; Jachinska, Katarzyna; Jacopini, Gioia; Jakobsen, Oda; Jamieson, Stuart; Jamrozik, Zygmunt; Janik, Piotr; Johns, Nicola; Jones, Lesley; Jones, Una; Jurgens, Caroline K.; Kaelin, Alain; Kalbarczyk, Anna; Kershaw, Ann; Khalil, Hanan; Kieni, Janina; Klimberg, Aneta; Koivisto, Susana P.; Koppers, Kerstin; Kosinski, Christoph Michael; Krawczyk, Malgorzata; Kremer, Berry; Krysa, Wioletta; Kwiecinski, Hubert; Lahiri, Nayana; Lambeck, Johann; Lange, Herwig; Laver, Fiona; Leenders, K.L.; Levey, Jamie; Leythaeuser, Gabriele; Lezius, Franziska; Llesoy, Joan Roig; Löhle, Matthias; López, Cristobal Diez-Aja; Lorenza, Fortuna; Loria, Giovanna; Magnet, Markus; Mandich, Paola; Marchese, Roberta; Marcinkowski, Jerzy; Mariotti, Caterina; Mariscal, Natividad; Markova, Ivana; Marquard, Ralf; Martikainen, Kirsti; Martínez, Isabel Haro; Martínez-Descals, Asuncion; Martino, T.; Mason, Sarah; McKenzie, Sue; Mechi, Claudia; Mendes, Tiago; Mestre, Tiago; Middleton, Julia; Milkereit, Eva; Miller, Joanne; Miller, Julie; Minster, Sara; Möller, Jens Carsten; Monza, Daniela; Morales, Blas; Moreau, Laura V.; Moreno, Jose L. López-Sendón; Münchau, Alexander; Murch, Ann; Nielsen, Jørgen E.; Niess, Anke; Nørremølle, Anne; Novak, Marianne; O'Donovan, Kristy; Orth, Michael; Otti, Daniela; Owen, Michael; Padieu, Helene; Paganini, Marco; Painold, Annamaria; Päivärinta, Markku; Partington-Jones, Lucy; Paterski, Laurent; Paterson, Nicole; Patino, Dawn; Patton, Michael; Peinemann, Alexander; Peppa, Nadia; Perea, Maria Fuensanta Noguera; Peterson, Maria; Piacentini, Silvia; Piano, Carla; Càrdenas, Regina Pons i; Prehn, Christian; Price, Kathleen; Probst, Daniela; Quarrell, Oliver; Quiroga, Purificacion Pin; Raab, Tina; Rakowicz, Maryla; Raman, Ashok; Raymond, Lucy; Reilmann, Ralf; Reinante, Gema; Reisinger, Karin; Retterstol, Lars; Ribaï, Pascale; Riballo, Antonio V.; Ribas, Guillermo G.; Richter, Sven; Rickards, Hugh; Rinaldi, Carlo; Rissling, Ida; Ritchie, Stuart; Rivera, Susana Vázquez; Robert, Misericordia Floriach; Roca, Elvira; Romano, Silvia; Romoli, Anna Maria; Roos, Raymond A.C.; Røren, Niini; Rose, Sarah; Rosser, Elisabeth; Rosser, Anne; Rossi, Fabiana; Rothery, Jean; Rudzinska, Monika; Ruíz, Pedro J. García; Ruíz, Belan Garzon; Russo, Cinzia Valeria; Ryglewicz, Danuta; Saft, Carston; Salvatore, Elena; Sánchez, Vicenta; Sando, Sigrid Botne; Šašinková, Pavla; Sass, Christian; Scheibl, Monika; Schiefer, Johannes; Schlangen, Christiane; Schmidt, Simone; Schöggl, Helmut; Schrenk, Caroline; Schüpbach, Michael; Schuierer, Michele; Sebastián, Ana Rojo; Selimbegovic-Turkovic, Amina; Sempolowicz, Justyna; Silva, Mark; Sitek, Emilia; Slawek, Jaroslaw; Snowden, Julie; Soleti, Francesco; Soliveri, Paola; Sollom, Andrea; Soltan, Witold; Sorbi, Sandro; Sorensen, Sven Asger; Spadaro, Maria; Städtler, Michael; Stamm, Christiane; Steiner, Tanja; Stokholm, Jette; Stokke, Bodil; Stopford, Cheryl; Storch, Alexander; Straßburger, Katrin; Stubbe, Lars; Sulek, Anna; Szczudlik, Andrzej; Tabrizi, Sarah; Taylor, Rachel; Terol, Santiago Duran-Sindreu; Thomas, Gareth; Thompson, Jennifer; Thomson, Aileen; Tidswell, Katherine; Torres, Maria M. Antequera; Toscano, Jean; Townhill, Jenny; Trautmann, Sonja; Tucci, Tecla; Tuuha, Katri; Uhrova, Tereza; Valadas, Anabela; van Hout, Monique S.E.; van Oostrom, J.C.H.; van Vugt, Jeroen P.P.; vanm, Walsem Marleen R.; Vandenberghe, Wim; Verellen-Dumoulin, Christine; Vergara, Mar Ruiz; Verstappen, C.C.P.; Verstraelen, Nichola; Viladrich, Celia Mareca; Villanueva, Clara; Wahlström, Jan; Warner, Thomas; Wehus, Raghild; Weindl, Adolf; Werner, Cornelius J.; Westmoreland, Leann; Weydt, Patrick; Wiedemann, Alexandra; Wild, Edward; Wild, Sue; Witjes-Ané, Marie-Noelle; Witkowski, Grzegorz; Wójcik, Magdalena; Wolz, Martin; Wolz, Annett; Wright, Jan; Yardumian, Pam; Yates, Shona; Yudina, Elizaveta; Zaremba, Jacek; Zaugg, Sabine W.; Zdzienicka, Elzbieta; Zielonka, Daniel; Zielonka, Euginiusz; Zinzi, Paola; Zittel, Simone; Zucker, Birgrit; Adams, John; Agarwal, Pinky; Antonijevic, Irina; Beck, Christopher; Chiu, Edmond; Churchyard, Andrew; Colcher, Amy; Corey-Bloom, Jody; Dorsey, Ray; Drazinic, Carolyn; Dubinsky, Richard; Duff, Kevin; Factor, Stewart; Foroud, Tatiana; Furtado, Sarah; Giuliano, Joe; Greenamyre, Timothy; Higgins, Don; Jankovic, Joseph; Jennings, Dana; Kang, Un Jung; Kostyk, Sandra; Kumar, Rajeev; Leavitt, Blair; LeDoux, Mark; Mallonee, William; Marshall, Frederick; Mohlo, Eric; Morgan, John; Oakes, David; Panegyres, Peter; Panisset, Michel; Perlman, Susan; Perlmutter, Joel; Quaid, Kimberly; Raymond, Lynn; Revilla, Fredy; Robertson, Suzanne; Robottom, Bradley; Sanchez-Ramos, Juan; Scott, Burton; Shannon, Kathleen; Shoulson, Ira; Singer, Carlos; Tabbal, Samer; Testa, Claudia; van, Kammen Dan; Vetter, Louise; Walker, Francis; Warner, John; Weiner, illiam; Wheelock, Vicki; Yastrubetskaya, Olga; Barton, Stacey; Broyles, Janice; Clouse, Ronda; Coleman, Allison; Davis, Robert; Decolongon, Joji; DeLaRosa, Jeanene; Deuel, Lisa; Dietrich, Susan; Dubinsky, Hilary; Eaton, Ken; Erickson, Diane; Fitzpatrick, Mary Jane; Frucht, Steven; Gartner, Maureen; Goldstein, Jody; Griffith, Jane; Hickey, Charlyne; Hunt, Victoria; Jaglin, Jeana; Klimek, Mary Lou; Lindsay, Pat; Louis, Elan; Loy, Clemet; Lucarelli, Nancy; Malarick, Keith; Martin, Amanda; McInnis, Robert; Moskowitz, Carol; Muratori, Lisa; Nucifora, Frederick; O'Neill, Christine; Palao, Alicia; Peavy, Guerry; Quesada, Monica; Schmidt, Amy; Segro, Vicki; Sperin, Elaine; Suter, Greg; Tanev, Kalo; Tempkin, Teresa; Thiede, Curtis; Wasserman, Paula; Welsh, Claire; Wesson, Melissa; Zauber, Elizabeth

    2012-01-01

    Objective: Age at onset of diagnostic motor manifestations in Huntington disease (HD) is strongly correlated with an expanded CAG trinucleotide repeat. The length of the normal CAG repeat allele has been reported also to influence age at onset, in interaction with the expanded allele. Due to profound implications for disease mechanism and modification, we tested whether the normal allele, interaction between the expanded and normal alleles, or presence of a second expanded allele affects age at onset of HD motor signs. Methods: We modeled natural log-transformed age at onset as a function of CAG repeat lengths of expanded and normal alleles and their interaction by linear regression. Results: An apparently significant effect of interaction on age at motor onset among 4,068 subjects was dependent on a single outlier data point. A rigorous statistical analysis with a well-behaved dataset that conformed to the fundamental assumptions of linear regression (e.g., constant variance and normally distributed error) revealed significance only for the expanded CAG repeat, with no effect of the normal CAG repeat. Ten subjects with 2 expanded alleles showed an age at motor onset consistent with the length of the larger expanded allele. Conclusions: Normal allele CAG length, interaction between expanded and normal alleles, and presence of a second expanded allele do not influence age at onset of motor manifestations, indicating that the rate of HD pathogenesis leading to motor diagnosis is determined by a completely dominant action of the longest expanded allele and as yet unidentified genetic or environmental factors. Neurology® 2012;78:690–695 PMID:22323755

  9. Late Pleistocene ice age scenarios based on observational evidence

    NASA Astrophysics Data System (ADS)

    Deblonde, G.; Peltier, W. R.

    1993-04-01

    Ice age scenarios for the last glacial-interglacial cycle, based on observations of Boyle and Keigwin (1982) concerning the North Atlantic thermohaline circulation and of Barnola et al. (1987) concerning atmospheric CO2 variations derived from the Vostok ice cores, are analyzed. Northern Hemisphere continental ice sheets are simulated with an energy balance model (EBM) that is asynchronously coupled to vertically integrated ice sheet models based on the Glen flow law. The EBM includes both a realistic land-sea distribution and temperature-albedo feedback and is driven with orbital variations of effective solar insolation. With the addition of atmospheric CO2 and ocean heat flux variations, but not in their absence, a complete collapse is obtained for the Eurasian ice sheet but not for the North American ice sheet. Further feedback mechanisms, perhaps involving more accurate modeling of the dynamics of the mostly marine-based Laurentide complex, appear necessary to explain termination I.

  10. Modeled tephra ages from lake sediments, base of Redoubt Volcano, Alaska

    USGS Publications Warehouse

    Schiff, C.J.; Kaufman, D.S.; Wallace, K.L.; Werner, A.; Ku, T.-L.; Brown, T.A.

    2008-01-01

    A 5.6-m-long lake sediment core from Bear Lake, Alaska, located 22 km southeast of Redoubt Volcano, contains 67 tephra layers deposited over the last 8750 cal yr, comprising 15% of the total thickness of recovered sediment. Using 12 AMS 14C ages, along with the 137Cs and 210Pb activities of recent sediment, we evaluated different models to determine the age-depth relation of the core, and to determine the age of each tephra deposit. The selected age model is based on a mixed-effect regression that was passed through the adjusted tephra-free depth of each dated layer. The estimated age uncertainty of the 67 tephras averages ??105 yr (95% confidence intervals). Tephra-fall frequency at Bear Lake was among the highest during the past 500 yr, with eight tephras deposited compared to an average of 3.7/500 yr over the last 8500 yr. Other periods of increased tephra fall occurred 2500-3500, 4500-5000, and 7000-7500 cal yr. Our record suggests that Bear Lake experienced extended periods (1000-2000 yr) of increased tephra fall separated by shorter periods (500-1000 yr) of apparent quiescence. The Bear Lake sediment core affords the most comprehensive tephrochronology from the base of the Redoubt Volcano to date, with an average tephra-fall frequency of one every 130 yr. ?? 2007 Elsevier Ltd. All rights reserved.

  11. Modeled tephra ages from lake sediments, base of Redoubt Volcano, Alaska

    SciTech Connect

    Schiff, C J; Kaufman, D S; Wallace, K L; Werner, A; Ku, T L; Brown, T A

    2007-02-25

    A 5.6-m-long lake sediment core from Bear Lake, Alaska, located 22 km southeast of Redoubt Volcano, contains 67 tephra layers deposited over the last 8750 cal yr, comprising 15% of the total thickness of recovered sediment. Using 12 AMS {sup 14}C ages, along with the {sup 137}Cs and {sup 210}Pb activities of recent sediment, we evaluated different models to determine the age-depth relation of sediment, and to determine the age of each tephra deposit. The age model is based on a cubic smooth spline function that was passed through the adjusted tephra-free depth of each dated layer. The estimated age uncertainty of the 67 tephras averages {+-} 105 yr (1{sigma}). Tephra-fall frequency at Bear Lake was among the highest during the past 500 yr, with eight tephras deposited compared to an average of 3.7 per 500 yr over the last 8500 yr. Other periods of increased tephra fall occurred 2500-3500, 4500-5000, and 7000-7500 cal yr. Our record suggests that Bear Lake experienced extended periods (1000-2000 yr) of increased tephra fall separated by shorter periods (500-1000 yr) of apparent quiescence. The Bear Lake sediment core affords the most comprehensive tephrochronology from the base of the Redoubt Volcano to date, with an average tephra-fall frequency of once every 130 yr.

  12. Classification of normal and pathological aging processes based on brain MRI morphology measures

    NASA Astrophysics Data System (ADS)

    Perez-Gonzalez, J. L.; Yanez-Suarez, O.; Medina-Bañuelos, V.

    2014-03-01

    Reported studies describing normal and abnormal aging based on anatomical MRI analysis do not consider morphological brain changes, but only volumetric measures to distinguish among these processes. This work presents a classification scheme, based both on size and shape features extracted from brain volumes, to determine different aging stages: healthy control (HC) adults, mild cognitive impairment (MCI), and Alzheimer's disease (AD). Three support vector machines were optimized and validated for the pair-wise separation of these three classes, using selected features from a set of 3D discrete compactness measures and normalized volumes of several global and local anatomical structures. Our analysis show classification rates of up to 98.3% between HC and AD; of 85% between HC and MCI and of 93.3% for MCI and AD separation. These results outperform those reported in the literature and demonstrate the viability of the proposed morphological indexes to classify different aging stages.

  13. A Comparison of the Accuracy of Four Age Estimation Methods Based on Panoramic Radiography of Developing Teeth

    PubMed Central

    Javadinejad, Shahrzad; Sekhavati, Hajar; Ghafari, Roshanak

    2015-01-01

    Background and aims. Tooth development is widely used in determining age and state of maturity. Dental age is of high importance in forensic and pediatric dentistry and also orthodontic treatment planning .The aim of this study was to compare the accuracy of four radiographic age estimation methods. Materials and methods. Orthopantomographic images of 537 healthy children (age: 3.9-14.5 years old) were evaluated. Dental age of the subjects was determined through Demirjian’s, Willem’s, Cameriere’s, and Smith’s methods. Differences and correlations between chronological and dental ages were assessed by paired t-tests and Pearson’s correlation analysis, respectively. Results. The mean chronological age of the subjects was 8.93 ± 2.04 years. Overestimations of age were observed following the use of Demirjian’s method (0.87 ± 1.00 years), Willem’s method (0.36 ± 0.87 years), and Smith’s method (0.06 ± 0.63 years). However, Cameriere’s method underestimated age by 0.19 ± 0.86 years. While paired t-tests revealed significant differences between the mean chronological age and ages determined by Demirjian’s, Willem’s, and Cameriere’s methods (P < 0.001), such a significant difference was absent between chronological age and dental age based on Smith’s method (P = 0.079). Pearson’s correlation analysis suggested linear correlations between chronological age and dental age determined by all four methods. Conclusion. Our findings indicated Smith’s method to have the highest accuracy among the four assessed methods. How-ever, all four methods can be used with acceptable accuracy. PMID:26236431

  14. Determination of equivalent breast phantoms for different age groups of Taiwanese women: An experimental approach

    SciTech Connect

    Dong, Shang-Lung; Chu, Tieh-Chi; Lin, Yung-Chien; Lan, Gong-Yau; Yeh, Yu-Hsiu; Chen, Sharon; Chuang, Keh-Shih

    2011-07-15

    Purpose: Polymethylmethacrylate (PMMA) slab is one of the mostly used phantoms for studying breast dosimetry in mammography. The purpose of this study was to evaluate the equivalence between exposure factors acquired from PMMA slabs and patient cases of different age groups of Taiwanese women in mammography. Methods: This study included 3910 craniocaudal screen/film mammograms on Taiwanese women acquired on one mammographic unit. The tube loading, compressed breast thickness (CBT), compression force, tube voltage, and target/filter combination for each mammogram were collected for all patients. The glandularity and the equivalent thickness of PMMA were determined for each breast using the exposure factors of the breast in combination with experimental measurements from breast-tissue-equivalent attenuation slabs. Equivalent thicknesses of PMMA to the breasts of Taiwanese women were then estimated. Results: The average {+-} standard deviation CBT and breast glandularity in this study were 4.2 {+-} 1.0 cm and 54% {+-} 23%, respectively. The average equivalent PMMA thickness was 4.0 {+-} 0.7 cm. PMMA slabs producing equivalent exposure factors as in the breasts of Taiwanese women were determined for the age groups 30-49 yr and 50-69 yr. For the 4-cm PMMA slab, the CBT and glandularity values of the equivalent breast were 4.1 cm and 65%, respectively, for the age group 30-49 yr and 4.4 cm and 44%, respectively, for the age group 50-69 yr. Conclusions: The average thickness of PMMA slabs producing the same exposure factors as observed in a large group of Taiwanese women is less than that reported for American women. The results from this study can provide useful information for determining a suitable thickness of PMMA for mammographic dose survey in Taiwan. The equivalence of PMMA slabs and the breasts of Taiwanese women is provided to allow average glandular dose assessment in clinical practice.

  15. Age Estimation Based on Children's Voice: A Fuzzy-Based Decision Fusion Strategy

    PubMed Central

    Ting, Hua-Nong

    2014-01-01

    Automatic estimation of a speaker's age is a challenging research topic in the area of speech analysis. In this paper, a novel approach to estimate a speaker's age is presented. The method features a “divide and conquer” strategy wherein the speech data are divided into six groups based on the vowel classes. There are two reasons behind this strategy. First, reduction in the complicated distribution of the processing data improves the classifier's learning performance. Second, different vowel classes contain complementary information for age estimation. Mel-frequency cepstral coefficients are computed for each group and single layer feed-forward neural networks based on self-adaptive extreme learning machine are applied to the features to make a primary decision. Subsequently, fuzzy data fusion is employed to provide an overall decision by aggregating the classifier's outputs. The results are then compared with a number of state-of-the-art age estimation methods. Experiments conducted based on six age groups including children aged between 7 and 12 years revealed that fuzzy fusion of the classifier's outputs resulted in considerable improvement of up to 53.33% in age estimation accuracy. Moreover, the fuzzy fusion of decisions aggregated the complementary information of a speaker's age from various speech sources. PMID:25006595

  16. A prospective study to compare serum human placental lactogen and menstrual dates for determining gestational age.

    PubMed

    Whittaker, P G; Lind, T; Lawson, J Y

    1987-01-01

    In a group of 575 healthy pregnant women with certain menstrual dates the estimation of the length of gestation from maternal serum human placental lactogen concentrations has been compared with gestational age calculated from the last menstrual period and ultrasonic measurements of the fetal biparietal diameter. In 412 of these patients labor started spontaneously, and the estimated dates of delivery determined by these three methods were also compared. In the range of 9 to 17 weeks of pregnancy, gestational age can be determined by human placental lactogen measurement to within 7 days (+/- 1 SD) which compares favorably with other methods. Regarding the prediction of the expected date of delivery, 88% were delivered within 2 weeks of the date predicted by last menstrual period, 82% within 2 weeks of the sonar date, and 80% by the date determined by human placental lactogen assessment. Prediction of delivery in a further group of 139 women with uncertain dates gave 73% within 2 weeks by sonar date and 69% within 2 weeks by human placental lactogen determination. We suggest human placental lactogen measurements should become part of routine antenatal care complementing rather than replacing the role of ultrasonic scanning. For those doctors and patients who wish to avoid more exposure to ultrasonic scanning than absolutely necessary, human placental lactogen estimates offer an alternative method for assessing the length of gestation.

  17. Mutual inhibition of insulin signaling and PHLPP-1 determines cardioprotective efficiency of Akt in aged heart

    PubMed Central

    Xing, Yuan; Sun, Wanqing; Wang, Yishi; Gao, Feng; Ma, Heng

    2016-01-01

    Insulin protects cardiomyocytes from myocardial ischemia/reperfusion (MI/R) injury through activating Akt. However, phosphatase PHLPP-1 (PH domain leucine-rich repeat protein phosphatase-1) dephosphorylates and inactivates Akt. The balanced competitive interaction of insulin and PHLPP-1 has not been directly examined. In this study, we have identified the effect of mutual inhibition of insulin signaling and PHLPP-1 on the cardioprotective efficiency of Akt in aged heart. Young (3 mon) and aged (20 mon) Sprague Dawley (SD) rats were subjected to MI/R in vivo. The PHLPP-1 level was higher in aged vs. young hearts at base. But, insulin treatment failed to decrease PHLPP-1 level during reperfusion in the aged hearts. Consequently, the cardioprotection of insulin-induced Akt activation was impaired in aged hearts, resulting in more susceptible to MI/R injury. In cultured rat ventricular myocytes, PHLPP-1 knockdown significantly enhanced insulin-induced Akt phosphorylation and reduced simulated hypoxia/reoxygenation-induced apoptosis. Contrary, PHLPP-1 overexpression terminated Akt phosphorylation and deteriorated myocytes apoptosis. Using in vivo aged animal models, we confirmed that cardiac PHLPP-1 knockdown or enhanced insulin sensitivity by exercise training dramatically increased insulin-induced Akt phosphorylation. Specifically, MI/R-induced cardiomyocyte apoptosis and infarct size were decreased and cardiac function was increased. More importantly, we found that insulin regulated the degradation of PHLPP-1 and insulin treatment could enhance the binding between PHLPP-1 and β-transducin repeat-containing protein (β-TrCP) to target for ubiquitin-dependent degradation. Altogether, we have identified a new mechanism by which insulin suppresses PHLPP-1 to enhance Akt activation. But, aged heart possesses lower insulin effectiveness and fails to decrease PHLPP-1 during MI/R, which subsequently limited Akt activity and cardioprotection. PHLPP-1 could be a promising

  18. Population Aging and the Determinants of Healthcare Expenditures: The Case of Hospital, Medical and Pharmaceutical Care in British Columbia, 1996 to 2006

    PubMed Central

    Cunningham, Colleen

    2011-01-01

    There is a gap between rhetoric and reality concerning healthcare expenditures and population aging: although decades-old research suggests otherwise, there is widespread belief that the sustainability of the healthcare system is under serious threat owing to population aging. To shed new empirical light on this old debate, we used population-based administrative data to quantify recent trends and determinants of expenditure on hospital, medical and pharmaceutical care in British Columbia. We modelled changes in inflation-adjusted expenditure per capita between 1996 and 2006 as a function of two demographic factors (population aging and changes in age-specific mortality rates) and three non-demographic factors (age-specific rates of use of care, quantities of care per user and inflation-adjusted costs per unit of care). We found that population aging contributed less than 1% per year to spending on medical, hospital and pharmaceutical care. Moreover, changes in age-specific mortality rates actually reduced hospital expenditure by —0.3% per year. Based on forecasts through 2036, we found that the future effects of population aging on healthcare spending will continue to be small. We therefore conclude that population aging has exerted, and will continue to exert, only modest pressures on medical, hospital and pharmaceutical costs in Canada. As indicated by the specific non-demographic cost drivers computed in our study, the critical determinants of expenditure on healthcare stem from non-demographic factors over which practitioners, policy makers and patients have discretion. PMID:22851987

  19. Fingermark age determinations: Legal considerations, review of the literature and practical propositions.

    PubMed

    Girod, A; Ramotowski, R; Lambrechts, S; Misrielal, P; Aalders, M; Weyermann, C

    2016-05-01

    The question of the age of fingermarks is often raised in investigations and trials when suspects admit that they have left their fingermarks at a crime scene but allege that the contact occurred at a different time than the crime and for legal reasons. In the first part of this review article, examples from American appellate court cases will be used to demonstrate that there is a lack of consensus among American courts regarding the admissibility and weight of testimony from expert witnesses who provide opinions about the age of fingermarks. Of course, these issues are not only encountered in America but have also been reported elsewhere, for example in Europe. The disparity in the way fingermark dating cases were managed in these examples is probably due to the fact that no methodology has been validated and accepted by the forensic science community so far. The second part of this review article summarizes the studies reported on fingermark dating in the literature and highlights the fact that most proposed methodologies still suffer from limitations preventing their use in practice. Nevertheless, several approaches based on the evolution of aging parameters detected in fingermark residue over time appear to show promise for the fingermark dating field. Based on these approaches, the definition of a formal methodological framework for fingermark dating cases is proposed in order to produce relevant temporal information. This framework identifies which type of information could and should be obtained about fingermark aging and what developments are still required to scientifically address dating issues.

  20. Fingermark age determinations: Legal considerations, review of the literature and practical propositions.

    PubMed

    Girod, A; Ramotowski, R; Lambrechts, S; Misrielal, P; Aalders, M; Weyermann, C

    2016-05-01

    The question of the age of fingermarks is often raised in investigations and trials when suspects admit that they have left their fingermarks at a crime scene but allege that the contact occurred at a different time than the crime and for legal reasons. In the first part of this review article, examples from American appellate court cases will be used to demonstrate that there is a lack of consensus among American courts regarding the admissibility and weight of testimony from expert witnesses who provide opinions about the age of fingermarks. Of course, these issues are not only encountered in America but have also been reported elsewhere, for example in Europe. The disparity in the way fingermark dating cases were managed in these examples is probably due to the fact that no methodology has been validated and accepted by the forensic science community so far. The second part of this review article summarizes the studies reported on fingermark dating in the literature and highlights the fact that most proposed methodologies still suffer from limitations preventing their use in practice. Nevertheless, several approaches based on the evolution of aging parameters detected in fingermark residue over time appear to show promise for the fingermark dating field. Based on these approaches, the definition of a formal methodological framework for fingermark dating cases is proposed in order to produce relevant temporal information. This framework identifies which type of information could and should be obtained about fingermark aging and what developments are still required to scientifically address dating issues. PMID:27044033

  1. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-Factor for Bench Aging Durability Procedures IX Appendix IX to Part 86 Protection of Environment... the R-Factor for Bench Aging Durability Procedures The R-Factor is the catalyst thermal reactivity coefficient used in the bench aging time (BAT) equation . Manufacturers may determine the value of...

  2. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-Factor for Bench Aging Durability Procedures IX Appendix IX to Part 86 Protection of Environment...-Factor for Bench Aging Durability Procedures The R-Factor is the catalyst thermal reactivity coefficient used in the bench aging time (BAT) equation . Manufacturers may determine the value of R...

  3. 29 CFR 570.31 - Secretary's determinations concerning the employment of minors 14 and 15 years of age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... minors 14 and 15 years of age. 570.31 Section 570.31 Labor Regulations Relating to Labor (Continued) WAGE... INTERPRETATION Employment of Minors Between 14 and 16 Years of Age (Child Labor Reg. 3) § 570.31 Secretary's determinations concerning the employment of minors 14 and 15 years of age. The employment of minors between...

  4. 29 CFR 570.31 - Secretary's determinations concerning the employment of minors 14 and 15 years of age.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... minors 14 and 15 years of age. 570.31 Section 570.31 Labor Regulations Relating to Labor (Continued) WAGE... determinations concerning the employment of minors 14 and 15 years of age. Link to an amendment published at 75... concerning the employment of minors 14 and 15 years of age. The employment of minors between 14 and 16...

  5. 29 CFR 570.31 - Secretary's determinations concerning the employment of minors 14 and 15 years of age.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... minors 14 and 15 years of age. 570.31 Section 570.31 Labor Regulations Relating to Labor (Continued) WAGE... INTERPRETATION Employment of Minors Between 14 and 16 Years of Age (Child Labor Reg. 3) § 570.31 Secretary's determinations concerning the employment of minors 14 and 15 years of age. The employment of minors between...

  6. 29 CFR 570.31 - Secretary's determinations concerning the employment of minors 14 and 15 years of age.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... minors 14 and 15 years of age. 570.31 Section 570.31 Labor Regulations Relating to Labor (Continued) WAGE... INTERPRETATION Employment of Minors Between 14 and 16 Years of Age (Child Labor Reg. 3) § 570.31 Secretary's determinations concerning the employment of minors 14 and 15 years of age. The employment of minors between...

  7. 29 CFR 570.31 - Secretary's determinations concerning the employment of minors 14 and 15 years of age.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... minors 14 and 15 years of age. 570.31 Section 570.31 Labor Regulations Relating to Labor (Continued) WAGE... INTERPRETATION Employment of Minors Between 14 and 16 Years of Age (Child Labor Reg. 3) § 570.31 Secretary's determinations concerning the employment of minors 14 and 15 years of age. The employment of minors between...

  8. A determination of surface ages of small geologic units on the terrestrial planets and satellites

    NASA Astrophysics Data System (ADS)

    Honda, C.; Morota, T.; Haruyama, J.

    We propose the suitable method of determination of surface age of the planets and satellites using smaller craters than 300 m in diameter which reveal the equilibrium saturation To determine these surface ages using the crater size-frequency distribution CSFD which has been useful method in the past planetary missions recently comes up against some kind of problems These include not only primary or secondary crater problems but also statistical problems We aimed at the fact that the depth of regolith layer was growing up with time by a number of impact craterings Since the scaling laws within the impact cratering on the sufficiently thinner regolith layer compared with the cross sectional depth of craters at the area are probably the strength regime the magnitude of the CSFD in the equilibrium saturation on the thinner regolith layer could be smaller than that on the thick regolith Otherwise the modification speed of the crater morphology on the thicker regolith layer is fast Consequently the magnitude of the CSFD could become small Schultz et al 1977 We evaluate these effects which are against each other using the images of same area taken at the different sun elevations In the future lunar mission SELENE we will be able to estimate the mostly absolute surface age if the accurate relationship between the CSFD and the structure under the lunar surface will become apparent

  9. Seasonality determines patterns of growth and age structure over a geographic gradient in an ectothermic vertebrate.

    PubMed

    Hjernquist, Mårten B; Söderman, Fredrik; Jönsson, K Ingemar; Herczeg, Gábor; Laurila, Anssi; Merilä, Juha

    2012-11-01

    Environmental variation connected with seasonality is likely to affect the evolution of life-history strategies in ectotherms, but there is no consensus as to how important life-history traits like body size are influenced by environmental variation along seasonal gradients. We compared adult body size, skeletal growth, mean age, age at first reproduction and longevity among 11 common frog (Rana temporaria) populations sampled along a 1,600-km-long latitudinal gradient across Scandinavia. Mean age, age at first reproduction and longevity increased linearly with decreasing growth season length. Lifetime activity (i.e. the estimated number of active days during life-time) was highest at mid-latitudes and females had on average more active days throughout their lives than males. Variation in body size was due to differences in lifetime activity among populations--individuals (especially females) were largest where they had the longest cumulative activity period--as well as to differences between populations in skeletal growth rate as determined by skeletochronological analyses. Especially, males grew faster at intermediate latitudes. While life-history trait variation was strongly associated with latitude, the direction and shape of these relationships were sex- and trait-specific. These context-dependent relationships may be the result of life-history trade-offs enforced by differences in future reproductive opportunities and time constraints among the populations. Thus, seasonality appears to be an important environmental factor shaping life-history trait variation in common frogs. PMID:22565493

  10. Age-associated B vitamin deficiency as a determinant of chronic diseases.

    PubMed

    Brachet, Patrick; Chanson, Aurélie; Demigné, Christian; Batifoulier, Frédérique; Alexandre-Gouabau, Marie-Cécile; Tyssandier, Viviane; Rock, Edmond

    2004-06-01

    The number of elderly individuals is growing rapidly worldwide and degenerative diseases constitute an increasing problem in terms of both public health and cost. Nutrition plays a role in the ageing process and there has been intensive research during the last decade on B vitamin-related risk factors in vascular and neurological diseases and cancers. Data from epidemiological studies indicate that subclinical deficiency in most water-soluble B vitamins may occur gradually during ageing, possibly due to environmental, metabolic, genetic, nutritional and pathological determinants, as well as to lifestyle, gender and drug consumption. Older adults have distinct absorption, cell transport and metabolism characteristics that may alter B vitamin bioavailability. Case-control and longitudinal studies have shown that, concurrent with an insufficient status of certain B vitamins, hyperhomocysteinaemia and impaired methylation reactions may be some of the mechanisms involved before a degenerative pathology becomes evident. The question that arises is whether B vitamin inadequacies contribute to the development of degenerative diseases or result from ageing and disease. The present paper aims to give an overview of these issues at the epidemiological, clinical and molecular levels and to discuss possible strategies to prevent B vitamin deficiency during ageing.

  11. Colorectal Cancer Screening Based on Age and Gender

    PubMed Central

    Wong, Martin C.S.; Ching, Jessica Y.L.; Chan, Victor C.W.; Lam, Thomas Y.T.; Luk, Arthur K.C.; Wong, Sunny H.; Ng, Siew C.; Ng, Simon S.M.; Wu, Justin C.Y.; Chan, Francis K.L.; Sung, Joseph J.Y.

    2016-01-01

    Abstract We evaluated whether age- and gender-based colorectal cancer screening is cost-effective. Recent studies in the United States identified age and gender as 2 important variables predicting advanced proximal neoplasia, and that women aged <60 to 70 years were more suited for sigmoidoscopy screening due to their low risk of proximal neoplasia. Yet, quantitative assessment of the incremental benefits, risks, and cost remains to be performed. Primary care screening practice (2008–2015). A Markov modeling was constructed using data from a screening cohort. The following strategies were compared according to the Incremental Cost Effectiveness Ratio (ICER) for 1 life-year saved: flexible sigmoidoscopy (FS) 5 yearly; colonoscopy 10 yearly; FS for each woman at 50- and 55-year old followed by colonoscopy at 60- and 70-year old; FS for each woman at 50-, 55-, 60-, and 65-year old followed by colonoscopy at 70-year old; FS for each woman at 50-, 55-, 60-, 65-, and 70-year old. All male subjects received colonoscopy at 50-, 60-, and 70-year old under strategies 3 to 5. From a hypothetical population of 100,000 asymptomatic subjects, strategy 2 could save the largest number of life-years (4226 vs 2268 to 3841 by other strategies). When compared with no screening, strategy 5 had the lowest ICER (US$42,515), followed by strategy 3 (US$43,517), strategy 2 (US$43,739), strategy 4 (US$47,710), and strategy 1 (US$56,510). Strategy 2 leads to the highest number of bleeding and perforations, and required a prohibitive number of colonoscopy procedures. Strategy 5 remains the most cost-effective when assessed with a wide range of deterministic sensitivity analyses around the base case. From the cost effectiveness analysis, FS for women and colonoscopy for men represent an economically favorable screening strategy. These findings could inform physicians and policy-makers in triaging eligible subjects for risk-based screening, especially in countries with limited colonoscopic

  12. The "Red Lady" ages gracefully: new ultrafiltration AMS determinations from Paviland.

    PubMed

    Jacobi, R M; Higham, T F G

    2008-11-01

    The "Red Lady" partial human skeleton found at Goat's Hole, Paviland, in south Wales by William Buckland in 1823 is one of the iconic relics of the British Paleolithic. Originally thought to be Roman, a Paleolithic age has been suspected from the middle of the 19th century. Several attempts have been made at directly radiocarbon dating the "Red Lady," and here we report new determinations that suggest that it is, by a significant margin, the oldest of a group of 'rich,' Mid-Upper Paleolithic burials. We list similar Gravettian-aged burials from Europe, which have been dated recently for comparison. In this paper, we also reconsider the chronology of human use of the cave, apart from as a burial location.

  13. 75 FR 57102 - Culturally Significant Objects Imported for Exhibition Determinations: “Titian and the Golden Age...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Titian and the Golden Age of... hereby determine that the objects to be included in the exhibition ``Titian and the Golden Age...

  14. 76 FR 56492 - Culturally Significant Objects Imported for Exhibition Determinations: “Antico: The Golden Age of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-13

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Antico: The Golden Age of..., 2003), I hereby determine that the objects to be included in the exhibition ``Antico: The Golden Age...

  15. Geomagnetic paleointensity and direct age determination of the ISEA (M0r?) chron

    NASA Astrophysics Data System (ADS)

    Zhu, Rixiang; Hoffman, Kenneth A.; Nomade, Sébastien; Renne, Paul R.; Shi, Ruiping; Pan, Yongxin; Shi, Guanghai

    2004-01-01

    A combined paleomagnetic and geochronologic study has been conducted on an andesite lava sequence at Jianguo (Liaoning province, northeastern China). Thermal demagnetization and thermomagnetic analysis revealed that natural remanent magnetization is carried by both magnetite and hematite. Stepwise thermal demagnetization up to 675°C isolated well-defined reverse characteristic remanent magnetization (ChRM) in three time-independent lava flows with a mean direction of D/ I=179.2°/-59.7° with α95=3.0°. It also showed that a high-temperature component (>585°C) has the same ChRM direction as that of the low- to medium-temperature (ca. 170/300-585°C) components. A modified version of the Thellier-Thellier paleointensity method [Coe, J. Geophys. Res. 72 (1967) 3247-3262] with systematic partial thermoremanent magnetization checks was used for paleointensity determinations. Twelve out of 39 samples yielded reliable results in the temperature interval of 170-550°C. Virtual dipole moment values range from 3.9 to 4.7×10 22 Am 2 with an average of 4.2±0.1×10 22 Am 2. 40Ar/ 39Ar age determination on one lava flow is 116.8±3.0 Myr (2σ error, relative to Fish Canyon sanidine: 28.02±0.28 Myr). The magnetic reversed polarity with well-defined age could correspond to the 'ISEA' within the older part of the Cretaceous normal superchron (CNS), but we cannot rule out the possibility that this reversal interval could also correspond to the M0r due to many ambiguities on previous published ages on ISEA and M0r intervals as well as the new monitor age correction we applied. It also suggests that a weak magnetic field nature already documented before the CNS extended at least into the very beginning of the CNS.

  16. Opposite differential risks for autism and schizophrenia based on maternal age, paternal age, and parental age differences

    PubMed Central

    Byars, Sean G.; Boomsma, Jacobus J.

    2016-01-01

    Background and objectives: Effects of maternal and paternal age on offspring autism and schizophrenia risks have been studied for over three decades, but inconsistent risks have often been found, precluding well-informed speculation on why these age-related risks might exist. Methodology: To help clarify this situation we analysed a massive single population sample from Denmark including the full spectrum of autistic and schizophrenic disorders (eliminating between-study confounding), used up to 30 follow-up years, controlled for over 20 potentially confounding factors and interpret the ultimate causation of the observed risk patterns using generally accepted principles of parent-offspring conflict and life-history theory. Results: We evaluated the effects of paternal age, maternal age and parental age difference on offspring mental disorders and found consistently similar risk patterns for related disorders and markedly different patterns between autistic and schizophrenic disorders. Older fathers and mothers both conferred increased risk for autistic but not schizophrenic disorders, but autism risk was reduced in younger parents and offspring of younger mothers had increased risk for many schizophrenic disorders. Risk for most disorders also increased when parents were more dissimilarly aged. Monotonically increasing autism risk is consistent with mutation accumulation as fathers’ age, but this explanation is invalid for schizophrenic disorders, which were not related to paternal age and were negatively correlated with maternal age. Conclusions and implications: We propose that the observed maternally induced risk patterns ultimately reflect a shifting ancestral life-history trade-off between current and future reproduction, mediated by an initially high but subsequently decreasing tendency to constrain foetal provisioning as women proceed from first to final pregnancy. PMID:27637201

  17. Personalizing Age of Cancer Screening Cessation Based on Comorbidity: Model estimates of harms and benefits

    PubMed Central

    Lansdorp-Vogelaar, Iris; Gulati, Roman; Mariotto, Angela B; Schechter, Clyde B; de Carvalho, Tiago M; Knudsen, Amy B; van Ravesteyn, Nicolien T; Heijnsdijk, Eveline AM; Pabiniak, Chester; van Ballegooijen, Marjolein; Rutter, Carolyn M; Kuntz, Karen M; Feuer, Eric J; Etzioni, Ruth; de Koning, Harry J; Zauber, Ann G; Mandelblatt, Jeanne S

    2014-01-01

    Background Harms and benefits of cancer screening depend on age and comorbidity, yet reliable estimates are lacking. Objective To estimate the harms and benefits of cancer screening by age and comorbidity to inform decisions about screening cessation. Design Collaborative modeling with seven well-established cancer simulation models and common data on average and comorbidity level-specific life expectancy from SEER-Medicare. Setting US population. Patients US cohorts aged 66–90 years in 2010 with average health or one of four comorbidity levels (linked to specific conditions): none, mild, moderate, or severe. Intervention Mammography, prostate-specific antigen testing, or fecal immunochemical testing. Measurements Lifetime cancer deaths prevented and life-years gained (benefits); false-positive tests and overdiagnosed cancers (harms). For each comorbidity level: the age at which harms and benefits of screening were similar to that for individuals with average health undergoing screening at age 74. Results Screening 1000 women with average life expectancy at age 74 for breast cancer resulted in 79–96 (range across models) false-positives, 0.5–0.8 overdiagnosed cancers, and 0.7–0.9 breast cancer deaths prevented. While absolute numbers of harms and benefits differed across cancer sites, the ages at which to cease screening were highly consistent across models and cancer sites when based on harm-benefit ratios comparable to screening average-health individuals at age 74. For individuals with no, mild, moderate, and severe comorbidities, screening until ages of 76, 74, 72, and 66, respectively, resulted in similar harms and benefits as for average-health individuals. Limitations Comorbidity only influenced life expectancy. Conclusion Comorbidity is an important determinant of harms and benefits of screening. Estimates of screening benefits and harms by comorbidity can inform discussions between providers and their older patients about personalizing decisions

  18. U-Pb systematics of the unique achondrite Ibitira: Precise age determination and petrogenetic implications

    NASA Astrophysics Data System (ADS)

    Iizuka, Tsuyoshi; Amelin, Yuri; Kaltenbach, Angela; Koefoed, Piers; Stirling, Claudine H.

    2014-05-01

    Ibitira is an unbrecciated, equilibrated vesicular basaltic achondrite that is considered to have originated on a parent body distinct from all other known meteorites. We present the first combined high-precision U and Pb isotopic data for this unique meteorite. The 238U/235U value of 137.777 ± 0.013 determined for the whole rock is comparable to values determined for bulk chondrites and other basaltic achondrites. This value results in corrections of -1.1 Ma for Pb-Pb dates calculated using the previously assumed invariant 238U/235U value of 137.88. Using the determined 238U/235U value, the 7 most radiogenic Pb isotopic analyses for acid-leached pyroxene-rich and whole rock fractions yield an isochron Pb-Pb age of 4556.75 ± 0.57 Ma, in excellent agreement with the results of Mn-Cr chronology which give the ages of 4557.4 ± 2.5 Ma and 4555.9 ± 3.2 Ma using the U-corrected Pb-Pb age of D'Orbigny as a time anchor. Along with the previously proposed thermal history of Ibitira and our closure temperature estimates for Pb diffusion, the Pb-Pb age is interpreted as the timing of the last chemical equilibration and coarse pyroxene exsolution that occurred during high temperature metamorphism. The metamorphism may have been caused by burial of Ibitira lava under successive lava flows and, if so, the Pb-Pb age should post-date the crystallization by a short time interval. The Pb isotopic data for acid leachates suggest partial re-equilibration of Pb between plagioclase and phosphate, perhaps during an impact event at 4.49 Ga, as recorded by K-Ar systematics. The whole rock 238U/204Pb indicates that compared to CI chondrites, Ibitira is less depleted in Pb than in some alkali elements despite a lower condensation temperature of Pb than the alkali elements. The restricted Pb depletion may reflect preferential concentration of metals with high fluid/melt partition coefficients including Pb and Zn as a result of fluid exsolution and migration within the parent magma. We

  19. Determinants of Anemia among School-Aged Children in Mexico, the United States and Colombia.

    PubMed

    Syed, Sana; Addo, O Yaw; De la Cruz-Góngora, Vanessa; Ashour, Fayrouz A Sakr; Ziegler, Thomas R; Suchdev, Parminder S

    2016-06-23

    Anemia affects approximately 25% of school-aged children (SAC-aged 5.00-14.99 years) globally. We determined in three countries the prevalence and determinants of anemia in SAC. Data on sociodemographics, inflammation and nutrition status were obtained from the 2006 Mexican National Nutrition Survey, the 2003-6 US National Health and Nutrition Examination Surveys, and the 2010 Encuesta Nacional de Nutrición Situación Colombia. In the US, vitamin A and iron deficiency (ID) were available only for girls aged 12.00-14.99 years to which our analysis was limited. Associations were evaluated by country using multivariable logistic regression adjusting for confounders and complex survey design. The prevalence of anemia and ID were: Mexico 12% (ID 18%), n = 3660; US 4% (ID 10%), n = 733; and Colombia 4% (ID 9%), n = 8573. The percentage of anemia associated with ID was 22.4% in Mexico, 38.9% in the US and 16.7% in Colombia. In Mexico, anemia was associated with ID (adjusted OR: 1.5, p = 0.02) and overweight (aOR 0.4, p = 0.007). In the US, anemia was associated with black race/ethnicity (aOR: 14.1, p < 0.0001) and ID (aOR: 8.0, p < 0.0001). In Colombia, anemia was associated with black race/ethnicity (aOR: 1.6, p = 0.005), lowest socio-economic status quintile (aOR: 1.8, p = 0.0005), ID (aOR: 2.7, p < 0.0001), and being stunted (aOR: 1.6, p = 0.02). While anemia was uniformly associated with iron deficiency in Mexico, Columbia, and the United States, other measured factors showed inconsistent associations with anemia. Additional data on anemia determinants in SAC are needed to guide interventions.

  20. Determinants of Anemia among School-Aged Children in Mexico, the United States and Colombia

    PubMed Central

    Syed, Sana; Addo, O. Yaw; De la Cruz-Góngora, Vanessa; Ashour, Fayrouz A. Sakr; Ziegler, Thomas R.; Suchdev, Parminder S.

    2016-01-01

    Anemia affects approximately 25% of school-aged children (SAC—aged 5.00–14.99 years) globally. We determined in three countries the prevalence and determinants of anemia in SAC. Data on sociodemographics, inflammation and nutrition status were obtained from the 2006 Mexican National Nutrition Survey, the 2003-6 US National Health and Nutrition Examination Surveys, and the 2010 Encuesta Nacional de Nutrición Situación Colombia. In the US, vitamin A and iron deficiency (ID) were available only for girls aged 12.00–14.99 years to which our analysis was limited. Associations were evaluated by country using multivariable logistic regression adjusting for confounders and complex survey design. The prevalence of anemia and ID were: Mexico 12% (ID 18%), n = 3660; US 4% (ID 10%), n = 733; and Colombia 4% (ID 9%), n = 8573. The percentage of anemia associated with ID was 22.4% in Mexico, 38.9% in the US and 16.7% in Colombia. In Mexico, anemia was associated with ID (adjusted OR: 1.5, p = 0.02) and overweight (aOR 0.4, p = 0.007). In the US, anemia was associated with black race/ethnicity (aOR: 14.1, p < 0.0001) and ID (aOR: 8.0, p < 0.0001). In Colombia, anemia was associated with black race/ethnicity (aOR: 1.6, p = 0.005), lowest socio-economic status quintile (aOR: 1.8, p = 0.0005), ID (aOR: 2.7, p < 0.0001), and being stunted (aOR: 1.6, p = 0.02). While anemia was uniformly associated with iron deficiency in Mexico, Columbia, and the United States, other measured factors showed inconsistent associations with anemia. Additional data on anemia determinants in SAC are needed to guide interventions. PMID:27347992

  1. Concordance of collagen-based radiocarbon and aspartic-acid racemization ages.

    PubMed

    Bada, J L; Schroeder, R A; Protsch, R; Berger, R

    1974-03-01

    By determining the extent of racemization of aspartic acid in a well-dated bone, it is possible to calculate the in situ first-order rate constant for the interconversion of the L and D enantiomers of aspartic acid. Collagen-based radiocarbon-dated bones are shown to be suitable samples for use in "calibrating" the racemization reaction. Once the aspartic-acid racemization reaction has been "calibrated" for a site, the reaction can be used to date other bones from the deposit. Ages deduced by this method are in good agreement with radiocarbon ages. These results provide evidence that the aspartic-acid racemization reaction is an important chronological tool for dating bones either too old or too small for radiocarbon dating. As an example of the potential application of the technique for dating fossil man, a piece of Rhodesian Man from Broken Hill, Zambia, was analyzed and tentatively assigned an age of about 110,000 years.

  2. Crustal subsidence rate off Hawaii determined from 234U/238U ages of drowned coral reefs

    USGS Publications Warehouse

    Ludwig, K. R.; Szabo, B. J.; Moore, J.G.; Simmons, K.R.

    1991-01-01

    A series of submerged coral reefs off northwestern Hawaii was formed during (largely glacial) intervals when the rate of local sea-level rise was less than the maximum upward growth rate of the reefs. Mass-spectrometric 234U/238U ages for samples from six such reefs range from 17 to 475 ka and indicate that this part of the Hawaiian Ridge has been subsiding at a roughly uniform rate of 2.6 mm/yr for the past 475 ka. The 234U/238U ages are in general agreement with model ages of reef drowning (based on estimates of paleo-sea-level stands derived from oxygen-isotope ratios of deep-sea sediments), but there are disagreements in detail. The high attainable precision (??10 ka or better on samples younger than ~800 ka), large applicable age range, relative robustness against open-system behavior, and ease of analysis for this technique hold great promise for future applications of dating of 50-1000 ka coral. -Authors

  3. Disentangling trait-based mortality in species with decoupled size and age.

    PubMed

    O'Farrell, Shay; Salguero-Gómez, Roberto; van Rooij, Jules M; Mumby, Peter J

    2015-09-01

    1. Size and age are fundamental organismal traits, and typically, both are good predictors of mortality. For many species, however, size and age predict mortality in ontogenetically opposing directions. Specifically, mortality due to predation is often more intense on smaller individuals whereas mortality due to senescence impacts, by definition, on older individuals. 2. When size-based and age-based mortality are independent in this manner, modelling mortality in both traits is often necessary. Classical approaches, such as Leslie or Lefkovitch matrices, usually require the model to infer the state of one trait from the state of the other, for example by assuming that explicitly modelled age (or stage) class structure provides implicit information on underlying size-class structure, as is the case in many species. 3. However, the assumption that one trait informs on the other is challenged when size and age are decoupled, as often occurs in invertebrates, amphibians, fish, reptiles and plants. In these cases, age-structured models may perform poorly at capturing size-based mortality, and vice versa. 4. We offer a solution to this dilemma, relaxing the assumption that class structure in one trait is inferable from class structure in another trait. Using empirical data from a reef fish, Sparisoma viride (Scaridae), we demonstrate how an individual-based model (IBM) can be implemented to model mortality as explicit, independent and simultaneous functions of individual size and age - an approach that mimics the effects of mortality in many wild populations. By validating this 'multitrait IBM' against three independent lines of empirical data, we determine that the approach produces more convincing predictions of size-class structure, longevity and post-settlement mortality for S. viride than do the trait-independent or single-trait mortality models tested. 5. Multitrait IBMs also allow trait-based mortality to be modelled either additively or multiplicatively, and

  4. Disentangling trait-based mortality in species with decoupled size and age.

    PubMed

    O'Farrell, Shay; Salguero-Gómez, Roberto; van Rooij, Jules M; Mumby, Peter J

    2015-09-01

    1. Size and age are fundamental organismal traits, and typically, both are good predictors of mortality. For many species, however, size and age predict mortality in ontogenetically opposing directions. Specifically, mortality due to predation is often more intense on smaller individuals whereas mortality due to senescence impacts, by definition, on older individuals. 2. When size-based and age-based mortality are independent in this manner, modelling mortality in both traits is often necessary. Classical approaches, such as Leslie or Lefkovitch matrices, usually require the model to infer the state of one trait from the state of the other, for example by assuming that explicitly modelled age (or stage) class structure provides implicit information on underlying size-class structure, as is the case in many species. 3. However, the assumption that one trait informs on the other is challenged when size and age are decoupled, as often occurs in invertebrates, amphibians, fish, reptiles and plants. In these cases, age-structured models may perform poorly at capturing size-based mortality, and vice versa. 4. We offer a solution to this dilemma, relaxing the assumption that class structure in one trait is inferable from class structure in another trait. Using empirical data from a reef fish, Sparisoma viride (Scaridae), we demonstrate how an individual-based model (IBM) can be implemented to model mortality as explicit, independent and simultaneous functions of individual size and age - an approach that mimics the effects of mortality in many wild populations. By validating this 'multitrait IBM' against three independent lines of empirical data, we determine that the approach produces more convincing predictions of size-class structure, longevity and post-settlement mortality for S. viride than do the trait-independent or single-trait mortality models tested. 5. Multitrait IBMs also allow trait-based mortality to be modelled either additively or multiplicatively, and

  5. Late pleistocene ice age scenarios based on observational evidence

    SciTech Connect

    DeBlonde, G. ); Peltier, W.R. )

    1993-04-01

    Ice age scenarios for the last glacial interglacial cycle, based on observations of Boyle and Keigwin concerning the North Atlantic thermohaline circulation and of Barnola et al. concerning atmospheric CO[sub 2] variations derived from the Vostok ice cores, are herein analyzed. Northern Hemisphere continental ice sheets are simulated with an energy balance model (EBM) that is asynchronously coupled to vertically integrated ice sheets models based on the Glen flow law. The EBM includes both a realistic land-sea distribution and temperature-albedo feedback and is driven with orbital variations of effective solar insolation. With the addition of atmospheric CO[sub 2] and ocean heat flux variations, but not in their absence, a complete collapse is obtained for the Eurasian ice sheet but not for the North American ice sheet. We therefore suggest that further feedback mechanisms, perhaps involving more accurate modeling of the dynamics of the mostly marine-based Laurentide complex appears necessary to explain termination I. 96 refs., 12 figs., 2 tabs.

  6. Determining soil-transmitted helminth infection status and physical fitness of school-aged children.

    PubMed

    Yap, Peiling; Fürst, Thomas; Müller, Ivan; Kriemler, Susi; Utzinger, Jürg; Steinmann, Peter

    2012-01-01

    , they often go unnoticed, are considered a normal condition by affected individuals, or are treated as symptoms of other diseases that might be more common in a given setting. Hence, it is conceivable that the true burden of STH infections is underestimated by assessment tools relying on self-declared signs and symptoms as is usually the case in population-based surveys. In the late 1980s and early 1990s, Stephenson and colleagues highlighted the possibility of STH infections lowering the physical fitness of boys aged 6-12 years. This line of scientific inquiry gained new momentum recently. The 20-meter (m) shuttle run test was developed and validated by Léger et al. and is used worldwide to measure the aerobic fitness of children. The test is easy to standardize and can be performed wherever a 20-m long and flat running course and an audio source are available, making its use attractive in resource-constrained settings. To facilitate and standardize attempts at assessing whether STH infections have an effect on the physical fitness of school-aged children, we present methodologies that diagnose STH infections or measure physical fitness that are simple to execute and yet, provide accurate and reproducible outcomes. This will help to generate new evidence regarding the health impact of STH infections. PMID:22951972

  7. Determining Soil-transmitted Helminth Infection Status and Physical Fitness of School-aged Children

    PubMed Central

    Yap, Peiling; Fürst, Thomas; Müller, Ivan; Kriemler, Susi; Utzinger, Jürg; Steinmann, Peter

    2012-01-01

    unspecific and subtle, they often go unnoticed, are considered a normal condition by affected individuals, or are treated as symptoms of other diseases that might be more common in a given setting. Hence, it is conceivable that the true burden of STH infections is underestimated by assessment tools relying on self-declared signs and symptoms as is usually the case in population-based surveys. In the late 1980s and early 1990s, Stephenson and colleagues highlighted the possibility of STH infections lowering the physical fitness of boys aged 6-12 years11,12. This line of scientific inquiry gained new momentum recently13,14,15. The 20-meter (m) shuttle run test was developed and validated by Léger et al.16 and is used worldwide to measure the aerobic fitness of children17. The test is easy to standardize and can be performed wherever a 20-m long and flat running course and an audio source are available, making its use attractive in resource-constrained settings13. To facilitate and standardize attempts at assessing whether STH infections have an effect on the physical fitness of school-aged children, we present methodologies that diagnose STH infections or measure physical fitness that are simple to execute and yet, provide accurate and reproducible outcomes. This will help to generate new evidence regarding the health impact of STH infections. PMID:22951972

  8. Can chlorofluorocarbon sorption to black carbon (char) affect groundwater age determinations?

    PubMed

    Choung, Sungwook; Allen-King, Richelle M

    2010-06-15

    Although adsorption is not generally considered important in low f(oc) (fraction organic carbon) aquifers, we show that chlorofluorocarbon (CFC) adsorption to black carbon (BC) is sufficiently large to retard transport and affect groundwater ages obtained with CFCs. Sorption isotherms of CFC-11, -12, and -113 to synthetic wood char were nonlinear (Freundlich n = 0.71-0.94) while humic acid isotherms were linear. Moreover, sorption to char was 10-1000 times greater than to humic acid for all three CFCs at the lowest observed concentrations, C(w)/S approximately 10(-8)-10(-7). We used the observed isotherms for char and humic acid to represent sorption to BC and amorphous organic matter, respectively, in a dual mode model to estimate retardation factors for a low f(oc) aquifer (= 0.06% gC g(-1)). The estimated retardation factors for the char-containing aquifer (presumed BC fraction = 9% of f(oc)) were approximately 6.8-10.6 at C(w)/S = 10(-8) and >5 times those estimated assuming amorphous organic matter partitioning only. The results indicate that unless CFC adsorption to BC is evaluated in transport, the groundwater age determined may be biased toward older than true ages. The CFC data archived in BC-containing aquifers may contain information about its adsorbent properties that could be useful to predict retardation of other chlorinated organic contaminants.

  9. Determining Distance, Age, and Activity in a New Benchmark Cluster: Ruprecht 147

    NASA Astrophysics Data System (ADS)

    Wright, Jason T.

    2009-08-01

    This proposal seeks 0.7 night of time on Hectochelle to observe the F, G, and K dwarfs of Ruprecht 147, recently identified as the closest old stellar cluster. At only ~ 200 pc and at an age of ~ 1-2 Gyr, this will be an important benchmark in stellar astrophysics, providing the only sample of spectroscopically accessible old, late-type stars of determinable age. Hectochelle is the ideal instrument to study this cluster, with a FOV, fiber count, and telescope aperture well matched to the cluster's diameter (~ 1°), richness (~ 100 identified members), and distance modulus (6.5-7 mag., putting the G and K dwarfs at B=11-15). Hectochelle will measure the Ca II line strengths of members to establish, for the first time, the chromospheric activity levels of a statistically significant sample of single, G and K dwarfs of this modest age. Hectochelle will also vet background stars for suitability as astrometric reference stars for a forthcoming HST FGS proposal to robustly measure the cluster's distance.

  10. Cation-ratio dating: A new rock varnish age-determination technique

    NASA Astrophysics Data System (ADS)

    Dorn, Ronald I.

    1983-07-01

    Rock varnish coats many surfaces of geomorphic and archaeologic interest in arid lands. All varnish dating techniques are limited by the time lag between the exposure of a surface to subaerial processes and the onset of varnishing. They are valid only where manganese is not remobilized after deposition, for example, in most arid environments. The premise of a new age-determination method, cation-ratio dating, is that the ratio of the more mobile cations (e.g., K and Ca) to titanium in varnish decreases with time. Although there are many inherent assumptions and potential limitations, cation-ratio dating has been verified on relative age-sequences from a Death Valley debris cone, Negev Desert talus flatirons, and prehistoric lake levels at Searles Lake in California. Varnish cation ratios have been calibrated to independently dated surfaces in the Coso volcanic field and vicinity in California. Tentative absolute dates have been assigned to geomorphic surfaces in the Coso area. Cation ratios have been used to distinguish relative ages of archaeologic artifacts in southwestern North America and to demonstrate that varnish at the South Stoddard locality, Mojave Desert, did not form in 25 yr.

  11. Anti-Aging Strategies Based on Cellular Reprogramming.

    PubMed

    Ocampo, Alejandro; Reddy, Pradeep; Izpisua Belmonte, Juan Carlos

    2016-08-01

    Aging can be defined as the progressive decline in the ability of a cell or organism to resist stress and disease. Recent advances in cellular reprogramming technologies have enabled detailed analyses of the aging process, often involving cell types derived from aged individuals, or patients with premature aging syndromes. In this review we discuss how cellular reprogramming allows the recapitulation of aging in a dish, describing novel experimental approaches to investigate the aging process. Finally, we explore the role of epigenetic dysregulation as a driver of aging, discussing how epigenetic reprogramming may be harnessed to ameliorate aging hallmarks, both in vitro and in vivo. A better understanding of the reprogramming process may indeed assist the development of novel therapeutic strategies to extend a healthy lifespan. PMID:27426043

  12. Age determination of mid-ocean ridge basalts by radiocarbon dating of lithified carbonate crusts

    SciTech Connect

    Kuptsov, V.M.; Bogdanov, Yu.A.; Palkina, A.M.; Lisitsyn, A.P.

    1986-01-01

    The processes that take place in the mid-ocean ridges are the key to their understanding of the evolution of the earth's crust and mantle. Mid-ocean ridge volcanism supplies vast masses of mantle material, forming new oceanic crust. In recent years, comprehensive study has been made of such processes. The problems of geochronology have an important place in these investigations, since only a study of the events in their time sequence will enable them to make a valid estimate of the intensity of these global processes. In 1980, crusts were obtained by the Pikar combined expedition in the Red Sea rift in the 18/sup 0/ study area on the lower tectonic terrace, in the axial zone, and in three deep water basins. Manned deep water submersible, dredges, trawls, bottom samplers, and impact tubes brought up basalts covered with lithified crusts, and also separate lithified crusts, collected from the basalt basement during sampling. The authors have dated the crusts by the radiocarbon method using the benzene technique. Results of the analysis give ages ranging from 2980 to 20,700 years. Results are discussed. The use of lithified carbonate crusts for determining the age of the basalts is effective within the range of the radiocarbon dating method (up to 40,000-45,000 years). This time interval is inaccessible for determinations by other methods of nuclear geochronology, which makes the method especially valuable. 1 reference, 2 figures, 1 table.

  13. In vitro determination of the anti-aging potential of four southern African medicinal plants

    PubMed Central

    2013-01-01

    Background Aging is an inevitable process for all living organisms. During this process reactive oxygen species generation is increased which leads to the activation of hyaluronidase, collagenase and elastase, which can further contribute to skin aging. Four southern African medicinal plants; Clerodendrum glabrum, Schotia brachypetala, Psychotria capensis and Peltophorum africanum, were investigated to assess their anti-aging properties. Methods Anti-elastase, anti-collagenase and anti-hyaluronidase activities of twenty-eight samples, consisting of methanol and ethyl acetate extracts of the four plants, were determined using spectrophotometric methods. Radical scavenging activity was determined by the ability of the plant extracts to scavenge the ABTS•+ radical. Results The majority of the samples in the anti-elastase assay and nine in the anti-collagenase assay showed more than 80% inhibition. The ethyl acetate extract of S. brachypetala bark and leaves of P. capensis inhibited elastase activity by more than 90%. The methanol extract of S. brachypetala bark contained the highest anti-hyaluronidase activity (75.13 ± 7.49%) whilst the ethyl acetate extract of P. africanum bark exhibited the highest antioxidant activity (IC50: 1.99 ± 0.23 μg/ml). Conclusion The free radical scavenging activity and enzyme inhibitory activity of the plant extracts investigated suggests that they can help restore skin elasticity and thereby slow the wrinkling process. P. africanum was the plant with the most promising activity and will be subjected to further testing and isolation of the active compound/s. PMID:24188320

  14. [Epidemiology of arbovirus diseases: use and value of physiologic age determination of female mosquito vectors].

    PubMed

    Mondet, B

    1996-01-01

    The physiological age of Yellow Fever Aedes females in Africa was studied during four years, from 1988 to 1992. We used a method, according to Polovodova's method, which looks for the "yellow body" under natural light. Those yellow bodies exist in the old females, the "parous" ones, and not in the young females, the "nulliparous" ones. We present some results to illustrate the interest of studying the physiological age of mosquitoes in the epidemiology of the arboviral diseases. The transmission risk, in relation with abundance and parity rate was illustrated, in particular for Aedes africanus and Aedes luteocephalus, which is useful to compare species, or with a given species, to compare periods. The parity rate of Aedes furcifer females was studied on 6 points along a transect between a forest and a village. The rate and the abundance of the females caught on human bates are inversely proportional. The parity rate is minimum in the canopy forest (about 50%) and maximum inside a house (100%). The rains have different consequences on the species, according to the period of fall. At the beginning of the dry season, they bring about hatching, but not at the end of the dry season. Massive hatching, will occur just at the beginning of the rainy season, some weeks later. Studying the physiological age of Ae. africanus females, the number of nulliparous is not related to the rain. That means a possibility of "natural" hatching for part of the eggs. Among the female of the dry season, young females are found, which is important for the transmission capacity. The method, described herein, to determine the physiological age is perfectly applicable to the Yellow Fever vector Haemagogus janthinomys in Southern America. But for the Dengue vectors Aedes aegypti and probably Aedes albopictus, the Detinova's method seems better. Actually, it seems important to study the physiological age of the vectors Ae. aegypti and Ae. albopictus, as well as the evolution of the physiological

  15. Lunar basalt chronology, mantle differentiation and implications for determining the age of the Moon

    NASA Astrophysics Data System (ADS)

    Snape, Joshua F.; Nemchin, Alexander A.; Bellucci, Jeremy J.; Whitehouse, Martin J.; Tartèse, Romain; Barnes, Jessica J.; Anand, Mahesh; Crawford, Ian A.; Joy, Katherine H.

    2016-10-01

    Despite more than 40 years of studying Apollo samples, the age and early evolution of the Moon remain contentious. Following the formation of the Moon in the aftermath of a giant impact, the resulting Lunar Magma Ocean (LMO) is predicted to have generated major geochemically distinct silicate reservoirs, including the sources of lunar basalts. Samples of these basalts, therefore, provide a unique opportunity to characterize these reservoirs. However, the precise timing and extent of geochemical fractionation is poorly constrained, not least due to the difficulty in determining accurate ages and initial Pb isotopic compositions of lunar basalts. Application of an in situ ion microprobe approach to Pb isotope analysis has allowed us to obtain precise crystallization ages from six lunar basalts, typically with an uncertainty of about ± 10 Ma, as well as constrain their initial Pb-isotopic compositions. This has enabled construction of a two-stage model for the Pb-isotopic evolution of lunar silicate reservoirs, which necessitates the prolonged existence of high-μ reservoirs in order to explain the very radiogenic compositions of the samples. Further, once firm constraints on U and Pb partitioning behaviour are established, this model has the potential to help distinguish between conflicting estimates for the age of the Moon. Nonetheless, we are able to constrain the timing of a lunar mantle reservoir differentiation event at 4376 ± 18 Ma, which is consistent with that derived from the Sm-Nd and Lu-Hf isotopic systems, and is interpreted as an average estimate of the time at which the high-μ urKREEP reservoir was established and the Ferroan Anorthosite (FAN) suite was formed.

  16. Socioeconomic determinants of risk of harmful alcohol drinking among people aged 50 or over in England

    PubMed Central

    Iparraguirre, José

    2015-01-01

    Objectives This paper looks into the socioeconomic determinants of risk of harmful alcohol drinking and of the transitions between risk categories over time among the population aged 50 or over in England. Setting Community-dwellers across England. Participants Respondents to the English Longitudinal Survey of Ageing, waves 4 and 5. Results (Confidence level at 95% or higher, except when stated): ▸ Higher risk drinking falls with age and there is a non-linear association between age and risk for men, peaking in their mid-60s. ▸ Retirement and income are positively associated with a higher risk for women but not for men. ▸ Education and smoking are positively associated for both sexes. ▸ Loneliness and depression are not associated. ▸ Caring responsibilities reduce risk among women. ▸ Single, separated or divorced men show a greater risk of harmful drinking (at 10% confidence level). ▸ For women, being younger and having a higher income at baseline increase the probability of becoming a higher risk alcohol drinker over time. ▸ For men, not eating healthily, being younger and having a higher income increase the probability of becoming a higher risk alcohol drinker. Furthermore, the presence of children living in the household, being lonely, being older and having a lower income are associated with ceasing to be a higher risk alcohol drinker over time. Conclusions Several socioeconomic factors found to be associated with high-risk alcohol consumption behaviour among older people would align with those promoted by the ‘successful ageing’ policy framework. PMID:26204909

  17. Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites

    USGS Publications Warehouse

    Zielinski, R.A.; Otton, J.K.; Budahn, J.R.

    2001-01-01

    Radium-bearing barite (radiobarite) is a common constituent of scale and sludge deposits that form in oil-field production equipment. The barite forms as a precipitate from radium-bearing, saline formation water that is pumped to the surface along with oil. Radioactivity levels in some oil-field equipment and in soils contaminated by scale and sludge can be sufficiently high to pose a potential health threat. Accurate determinations of radium isotopes (226Ra+228Ra) in soils are required to establish the level of soil contamination and the volume of soil that may exceed regulatory limits for total radium content. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant. Age estimates require that highly insoluble radiobarite approximates a chemically closed system from the time of its formation. Age estimates are based on the decay of short-lived 228Ra (half-life=5.76 years) compared to 226Ra (half-life=1600 years). Present activity ratios of 228Ra/226Ra in radiobarite-rich scale or highly contaminated soil are compared to initial ratios at the time of radiobarite precipitation. Initial ratios are estimated by measurements of saline water or recent barite precipitates at the site or by considering a range of probable initial ratios based on reported values in modern oil-field brines. At sites that contain two distinct radiobarite sources of different age, the soils containing mixtures of sources can be identified, and mixing proportions quantified using radium concentration and isotopic data. These uses of radium isotope data provide more description of contamination history and can possibly address liability issues. Copyright ?? 2000 .

  18. Age-correlated stress resistance improves fitness of yeast: support from agent-based simulations

    PubMed Central

    2014-01-01

    Background Resistance to stress is often heterogeneous among individuals within a population, which helps protect against intermittent stress (bet hedging). This is also the case for heat shock resistance in the budding yeast Saccharomyces cerevisiae. Interestingly, the resistance appears to be continuously distributed (vs. binary, switch-like) and correlated with replicative age (vs. random). Older, slower-growing cells are more resistant than younger, faster-growing ones. Is there a fitness benefit to age-correlated stress resistance? Results Here this hypothesis is explored using a simple agent-based model, which simulates a population of individual cells that grow and replicate. Cells age by accumulating damage, which lowers their growth rate. They synthesize trehalose at a metabolic cost, which helps protect against heat shock. Proteins Tsl1 and Tps3 (trehalose synthase complex regulatory subunit TSL1 and TPS3) represent the trehalose synthesis complex and they are expressed using constant, age-dependent and stochastic terms. The model was constrained by calibration and comparison to data from the literature, including individual-based observations obtained using high-throughput microscopy and flow cytometry. A heterogeneity network was developed, which highlights the predominant sources and pathways of resistance heterogeneity. To determine the best trehalose synthesis strategy, model strains with different Tsl1/Tps3 expression parameters were placed in competition in an environment with intermittent heat shocks. Conclusions For high severities and low frequencies of heat shock, the winning strain used an age-dependent bet hedging strategy, which shows that there can be a benefit to age-correlated stress resistance. The study also illustrates the utility of combining individual-based observations and modeling to understand mechanisms underlying population heterogeneity, and the effect on fitness. PMID:24529069

  19. Using the gradient of human cortical bone properties to determine age-related bone changes via ultrasonic guided waves.

    PubMed

    Baron, Cécile

    2012-06-01

    Bone fragility depends not only on bone mass but also on bone quality (structure and material). To accurately evaluate fracture risk or propose therapeutic treatment, clinicians need a criterion, which reflects the determinants of bone strength: geometry, structure and material. In human long bone, the changes due to aging, accentuated by osteoporosis are often revealed through the trabecularization of cortical bone, i.e., increased porosity of endosteal bone inducing a thinning of the cortex. Consequently, the intracortical porosity gradient corresponding to the spatial variation in porosity across the cortical thickness is representative of loss of mass, changes in geometry (thinning) and variations in structure (porosity). This article examines the gradient of material properties and its age-related evolution as a relevant parameter to assess bone geometry, structure and material. By applying a homogenization process, cortical bone can be considered as an anisotropic functionally graded material with variations in material properties. A semi-analytical method based on the sextic Stroh formalism is proposed to solve the wave equation in an anisotropic functionally graded waveguide for two geometries, a plate and a tube, without using a multilayered model to represent the structure. This method provides an analytical solution called the matricant and explicitly expressed under the Peano series expansion form. Our findings indicate that ultrasonic guided waves are sensitive to the age-related evolution of realistic gradients in human bone properties across the cortical thickness and have their place in a multimodal clinical protocol.

  20. Age determinations and growth rates of Pacific ferromanganese deposits using strontium isotopes

    USGS Publications Warehouse

    Ingram, B.L.; Hein, J.R.; Farmer, G.L.

    1990-01-01

    87Sr 86Sr ratios, trace element and REE compositions, and textural characteristics were determined for three hydrogenetic Fe-Mn crusts, one hydrothermal deposit, and two mixed hydrothermalhydrogenetic crusts from the Pacific. The Sr isotope data are compared to the Sr seawater curve for the Cenozoic to determine the ages and growth rates of the crusts. The 87Sr 86Sr in the crusts does not increase monotonically with depth as expected if the Sr were solely derived from seawater and perfectly preserved since deposition. This indicates post-depositional exchange of Sr or heterogeneous sources for the Sr originally contained in the crusts. Textures of hydrogenetic crusts generally correlate with Sr isotopic variations. The highest porosity intervals commonly exhibit the highest 87Sr 86Sr ratios, indicating exchange with younger seawater. Intervals with the lowest porosity commonly have lower 87Sr 86Sr and may preserve the original Sr isotopic ratios. Minimum ages of crust growth inception were calculated from dense, low porosity intervals. Growth of the hydrogenetic crusts began at or after 23 Ma, although their substrates are Cretaceous. Estimated average growth rates of the three hydrogenetic crusts vary between 0.9 and 2.7 mm/Ma, consistent with published rates determined by other techniques. Within the Marshall Islands crust, growth rates for individual layers varied greatly between 1.0 and 5.4 mm/Ma. For one crust, very low 87Sr 86Sr ratios occurred in detrital-rich intervals. Hydrothermal Fe-Mn oxide from the active Lau Basin back-arc spreading axis (Valu Fa Ridge) has an 87Sr 86Sr ratio with a predominantly seawater signature ( 87Sr 86Sr 0.709196), indicating a maximum age of 0.9 Ma. One crust from an off-axis seamount west of Gorda Ridge may have begun precipitating hydrogenetically at 0.5 Ma (0.709211), and had increasing hydrothermal or volcanic input in the top half of the crust, indicated by a significantly lower 87Sr 86Sr ratio (0.709052). ?? 1990.

  1. Prototype development of a microprocessor based onboard orbit determination system

    NASA Technical Reports Server (NTRS)

    Tasaki, K. K.; Pajerski, R. S.

    1980-01-01

    An automated orbit determination system (AODS) is described. The AODS is used in conjunction with an orbital simulator. The system, based on microprocessors, enables onboard orbital position estimation.

  2. Differences in duration of Huntington's disease based on age at onset

    PubMed Central

    Foroud, T.; Gray, J.; Ivashina, J.; Conneally, P

    1999-01-01

    OBJECTIVES—Data from a sample of 2494 patients affected with Huntington's disease (HD), collected as part of the National Research Roster for Huntington Disease Patients and Families, were examined to determine if there was a relation between age at onset and duration of illness.
METHODS—Sufficient data for inclusion in analysis was available from 2068 patients, of whom 828 were deceased and 1240 were living. The median duration of disease was 21.4 years with a range of 1.2 to 40.8 years. Patients were categorised into one of four groups based on their age at onset.
RESULTS—Significant differences in duration based on the age at onset were found (p<0.025), with juvenile and late onset patients with HD having shorter duration of illness compared with those with an onset between 20-49 years.
CONCLUSIONS—Duration of disease is influenced by the age at symptom onset with juvenile and late onset patients having the shortest duration.

 PMID:9886451

  3. Estimating the color of maxillary central incisors based on age and gender

    PubMed Central

    Gozalo-Diaz, David; Johnston, William M.; Wee, Alvin G.

    2008-01-01

    Statement of problem There is no scientific information regarding the selection of the color of teeth for edentulous patients. Purpose The purpose of this study was to evaluate linear regression models that may be used to predict color parameters for central incisors of edentulous patients based on some characteristics of dentate subjects. Material and methods A spectroradiometer and an external light source were set in a noncontacting 45/0 degree (45-degree illumination and 0-degree observer) optical configuration to measure the color of subjects’ vital craniofacial structures (maxillary central incisor, attached gingiva, and facial skin). The subjects (n=120) were stratified into 5 age groups with 4 racial groups and balanced for gender. Linear first-order regression was used to determine the significant factors (α=.05) in the prediction model for each color direction of the color of the maxillary central incisor. Age, gender, and color of the other craniofacial structures were studied as potential predictors. Final predictions in each color direction were based only on the statistically significant factors, and then the color differences between observed and predicted CIELAB values for the central incisors were calculated and summarized. Results The statistically significant predictors of age and gender accounted for 36% of the total variability in L*. The statistically significant predictor of age accounted for 16% of the total variability in a*. The statistically significant predictors of age and gender accounted for 21% of the variability in b*. The mean ΔE (SD) between predicted and observed CIELAB values for the central incisor was 5.8 (3.2). Conclusions Age and gender were found to be statistically significant determinants in predicting the natural color of central incisors. Although the precision of these predictions was less than the median color difference found for all pairs of teeth studied, and may be considered an acceptable precision, further

  4. Age and season determine European rabbit habitat use in Mediterranean ecosystems

    NASA Astrophysics Data System (ADS)

    Rueda, Marta; Rebollo, Salvador; Bravo, Lucía Gálvez

    2008-11-01

    Knowledge about the factors determining habitat use is especially interesting for herbivores living under seasonal climates as they have to deal with food shortage during the drought season. In this context, different-aged individuals are expected to respond differently to seasonal variations because nutritional requirements and predation risk can vary with age. We investigated adult and juvenile European rabbit ( Oryctolagus cuniculus) habitat use in a Mediterranean ecosystem of central Spain, during spring, summer and winter. Relationships between adult and juvenile rabbit pellet abundances and 11 environmental variables related to food availability and refuge density were analysed by means of multiple regression, and evaluated using information theory to identify the set of models best supported by the data. Density of warren entrances was the more constant predictor of habitat use for juvenile rabbits in all the seasons. Herbaceous vegetation volume had a negative influence and was the strongest predictor for adult rabbit habitat use in spring and winter. In summer, green vegetation cover became the strongest positive habitat use predictor. These results suggest that adults prefer to forage in low volume swards ensuring a wide sensory range for the detection of approaching predators. However, the arrival of summer and its associated food depletion forces them to shift toward more open productive areas where green vegetation persists, but at the expense of higher predation risk. Seasonal variation induces minor changes in juvenile habitat use due to their strong dependence on warrens. Thus, our results show that rabbit habitat use is influenced by animal age and seasonal variations in resources.

  5. Hormesis, cellular stress response and vitagenes as critical determinants in aging and longevity.

    PubMed

    Calabrese, Vittorio; Cornelius, Carolin; Cuzzocrea, Salvatore; Iavicoli, Ivo; Rizzarelli, Enrico; Calabrese, Edward J

    2011-08-01

    Understanding mechanisms of aging and determinants of life span will help to reduce age-related morbidity and facilitate healthy aging. Average lifespan has increased over the last centuries, as a consequence of medical and environmental factors, but maximal life span remains unchanged. Extension of maximal life span is currently possible in animal models with measures such as genetic manipulations and caloric restriction (CR). CR appears to prolong life by reducing reactive oxygen species (ROS)-mediated oxidative damage. But ROS formation, which is positively implicated in cellular stress response mechanisms, is a highly regulated process controlled by a complex network of intracellular signaling pathways. By sensing the intracellular nutrient and energy status, the functional state of mitochondria, and the concentration of ROS produced in mitochondria, the longevity network regulates life span across species by co-ordinating information flow along its convergent, divergent and multiply branched signaling pathways, including vitagenes which are genes involved in preserving cellular homeostasis during stressful conditions. Vitagenes encode for heat shock proteins (Hsp) Hsp32, Hsp70, the thioredoxin and the sirtuin protein systems. Dietary antioxidants, such as carnosine, carnitines or polyphenols, have recently been demonstrated to be neuroprotective through the activation of hormetic pathways, including vitagenes. The hormetic dose-response, challenges long-standing beliefs about the nature of the dose-response in a lowdose zone, having the potential to affect significantly the design of pre-clinical studies and clinical trials as well as strategies for optimal patient dosing in the treatment of numerous diseases. Given the broad cytoprotective properties of the heat shock response there is now strong interest in discovering and developing pharmacological agents capable of inducing stress responses. In this review we discuss the most current and up to date

  6. Determination of the Rubidium Decay Constant by Age Comparison Against the U-Pb System

    NASA Astrophysics Data System (ADS)

    Nebel, O.; Mezger, K.; Scherer, E. E.; Davies, G. R.

    2006-12-01

    The currently accepted Rb decay constant (λ 87Rb) was suggested by the Subcommission on Geochronology [1] is 1.42 x 10-11yr-1, and has a potential precision at the percent level at best [2]. This value has been used in most Rb-Sr studies in the last three decades. Several attempts to refine λ87Rb by different techniques yielded results that, despite excellent reported precisions, differed from the proposed value and also from each other. In a recent evaluation of published calibrations of the decay constant, Begemann et al. [2] suggested a lower value [~ 1.40 x 10-11yr-1] but also called for a re-determination of λ87Rb to check its accuracy and significantly improve the precision. Subsequent re-determinations [3,4] yielded values that differ significantly from each other and from that proposed by the Subcommission on Geochronology [1], one of which being higher [3], the other one lower [4] than the recommended value. Therefore, at present, there is no consensus on the λ87Rb to be used in Rb-Sr chronology. Here we report three individual determinations of λ87Rb by the method of age comparison. This entails solving for λ87Rb using 1) the measured slopes of high precision Rb-Sr isochrons from igneous rocks and minerals and 2) the emplacement ages of these samples as determined by the precise and presumably accurate U-Pb method. The precision of the measured 87Rb/86Sr has been improved to ~0.2% by measuring Rb concentrations by isotope dilution MC-ICPMS [5] (cf. ~1% for TIMS data). A challenging aspect of Rb-Sr studies is that of spike calibration, which is generally performed using standards prepared from salts of Rb and Sr rather than pure metals. The Rb/Sr values of individual spikes calibrated against two standard solutions made from different salts (iodide and carbonate) agree to within 0.15%, strongly suggesting that the stoichiometry of the salts, after careful dehydration, is sufficiently ideal for accurate spike calibrations. The calibration was checked

  7. Determinants of Anemia and Hemoglobin Concentration in Haitian School-Aged Children.

    PubMed

    Iannotti, Lora L; Delnatus, Jacques R; Odom, Audrey R; Eaton, Jacob C; Griggs, Jennifer J; Brown, Sarah; Wolff, Patricia B

    2015-11-01

    Anemia diminishes oxygen transport in the body, resulting in potentially irreversible growth and developmental consequences for children. Limited evidence for determinants of anemia exists for school-aged children. We conducted a cluster randomized controlled trial in Haiti from 2012 to 2013 to test the efficacy of a fortified school snack. Children (N = 1,047) aged 3-13 years were followed longitudinally at three time points for hemoglobin (Hb) concentrations, anthropometry, and bioelectrical impedance measures. Dietary intakes, infectious disease morbidities, and socioeconomic and demographic factors were collected at baseline and endline. Longitudinal regression modeling with generalized least squares and logit models with random effects identified anemia risk factors beyond the intervention effect. At baseline, 70.6% of children were anemic and 2.6% were severely anemic. Stunting increased the odds of developing anemia (adjusted odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.05-2.08) and severe anemia (adjusted OR: 2.47, 95% CI: 1.30-4.71). Parent-reported vitamin A supplementation and deworming were positively associated with Hb concentrations, whereas fever and poultry ownership showed a negative relationship with Hb concentration and increased odds of severe anemia, respectively. Further research should explore the full spectrum of anemia etiologies in school children, including genetic causes.

  8. Determination of age and growth of Buccinum undatum L. (Gastropoda) off Douglas, Isle of Man

    NASA Astrophysics Data System (ADS)

    Kideys, A. E.

    1996-09-01

    Age and growth of Buccinum undatum off Douglas (Isle of Man, U.K.) were studied using four independent methods: length-frequency analyses (LFA), operculum analysis (OA), markrecapture experiment (MRE) and laboratory rearing (LR). Within the 16-month period between February 1989 and June 1990, only the January 1990 sample showed histograms allowing possible age group determination. Among the several length frequency analyses applied to this sample, the growth analysis program MIX calculated that Buccinum reaches mean lengths of 28.5, 45.8, 59.9, 71.5 and 81.0 mm at the end of its first, second, third, fourth and fifth year, respectively, with an asymptotic length (L∞) of 123.8 mm and Brody growth coefficient (K) of 0.20. Whilst the results from the LFA were supported by those from the OA and the MRE, growth in the laboratory differed; however, this was expected. Both K and L values found in this study are higher than those in two previous studies undertaken for Buccinum in northeastern England and northern France.

  9. Determinants of Anemia and Hemoglobin Concentration in Haitian School-Aged Children.

    PubMed

    Iannotti, Lora L; Delnatus, Jacques R; Odom, Audrey R; Eaton, Jacob C; Griggs, Jennifer J; Brown, Sarah; Wolff, Patricia B

    2015-11-01

    Anemia diminishes oxygen transport in the body, resulting in potentially irreversible growth and developmental consequences for children. Limited evidence for determinants of anemia exists for school-aged children. We conducted a cluster randomized controlled trial in Haiti from 2012 to 2013 to test the efficacy of a fortified school snack. Children (N = 1,047) aged 3-13 years were followed longitudinally at three time points for hemoglobin (Hb) concentrations, anthropometry, and bioelectrical impedance measures. Dietary intakes, infectious disease morbidities, and socioeconomic and demographic factors were collected at baseline and endline. Longitudinal regression modeling with generalized least squares and logit models with random effects identified anemia risk factors beyond the intervention effect. At baseline, 70.6% of children were anemic and 2.6% were severely anemic. Stunting increased the odds of developing anemia (adjusted odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.05-2.08) and severe anemia (adjusted OR: 2.47, 95% CI: 1.30-4.71). Parent-reported vitamin A supplementation and deworming were positively associated with Hb concentrations, whereas fever and poultry ownership showed a negative relationship with Hb concentration and increased odds of severe anemia, respectively. Further research should explore the full spectrum of anemia etiologies in school children, including genetic causes. PMID:26350448

  10. Lens opacity based modelling of the age-related straylight increase.

    PubMed

    Rozema, Jos J; Sanchez, Victoria; Artal, Natalia; Gramajo, Ana L; Torres, Eduardo; Luna, Jose D; Iribarren, Rafael; Tassignon, Marie-José; Juarez, Claudio P

    2015-12-01

    This work studies ethnic and geographical differences in the age-related straylight increase by means of a stochastic model and unpublished lens opacity data of 559 residents of Villa Maria (Argentina), as well as data of 912 Indonesian subjects published previously by Husain et al. For both cohorts the prevalence of each type and grade of lens opacity was determined as a function of age, from which a stochastic model was derived capable of simulating the lens opacity prevalence for both populations. These simulated lens opacity data were then converted to estimated straylight by means of an equation derived from previously recorded data of 107 eyes with varying degrees of cataract. Based on these opacity templates 2500 random sets of subject age and lens opacity data were generated by the stochastic model for each dataset, from which estimated straylight could be calculated. For the Argentinian data the estimated straylight was found to closely resemble the published models for age-related straylight increase. For younger eyes the straylight variation of the model was the same as what was previously published (in both cases ±0.200logunits), which doubled in size for older eyes. For the Indonesian data, however, this age-related straylight increase was found to be fundamentally different from the published age model. This suggests that current normative curves for age-related straylight increase may not always be appropriate for non-European populations, and that the inter-individual straylight variations in young, healthy eyes may possibly be due to variations in lens opacities.

  11. General fusion approaches for the age determination of latent fingerprint traces: results for 2D and 3D binary pixel feature fusion

    NASA Astrophysics Data System (ADS)

    Merkel, Ronny; Gruhn, Stefan; Dittmann, Jana; Vielhauer, Claus; Bräutigam, Anja

    2012-03-01

    Determining the age of latent fingerprint traces found at crime scenes is an unresolved research issue since decades. Solving this issue could provide criminal investigators with the specific time a fingerprint trace was left on a surface, and therefore would enable them to link potential suspects to the time a crime took place as well as to reconstruct the sequence of events or eliminate irrelevant fingerprints to ensure privacy constraints. Transferring imaging techniques from different application areas, such as 3D image acquisition, surface measurement and chemical analysis to the domain of lifting latent biometric fingerprint traces is an upcoming trend in forensics. Such non-destructive sensor devices might help to solve the challenge of determining the age of a latent fingerprint trace, since it provides the opportunity to create time series and process them using pattern recognition techniques and statistical methods on digitized 2D, 3D and chemical data, rather than classical, contact-based capturing techniques, which alter the fingerprint trace and therefore make continuous scans impossible. In prior work, we have suggested to use a feature called binary pixel, which is a novel approach in the working field of fingerprint age determination. The feature uses a Chromatic White Light (CWL) image sensor to continuously scan a fingerprint trace over time and retrieves a characteristic logarithmic aging tendency for 2D-intensity as well as 3D-topographic images from the sensor. In this paper, we propose to combine such two characteristic aging features with other 2D and 3D features from the domains of surface measurement, microscopy, photography and spectroscopy, to achieve an increase in accuracy and reliability of a potential future age determination scheme. Discussing the feasibility of such variety of sensor devices and possible aging features, we propose a general fusion approach, which might combine promising features to a joint age determination scheme

  12. Osteoarthritis of finger joints in Finns aged 30 or over: prevalence, determinants, and association with mortality

    PubMed Central

    Haara, M; Manninen, P; Kroger, H; Arokoski, J; Karkkainen, A; Knekt, P; Aromaa, A; Heliovaara, M

    2003-01-01

    Background: Prevalence and risk factors of osteoarthritis (OA) in finger joints have been amply explored in previous studies. However, no study has focused on finger joint OA as a predictor of mortality. Objective: To investigate finger joint OA for its associations with alleged risk factors and with life expectancy in an extensive health survey. Methods: From 1978 to 1980 a representative population sample of 8000 Finns aged 30 years or over was invited to participate in a comprehensive health examination; 90% accepted. Hand radiographs were taken from 3595 subjects. By the end of 1994, 897 of these had died. Results: The prevalence of OA of Kellgren's grade 2 to 4 in any finger joint and in at least two symmetrical pairs of distal interphalangeal joints (DIPs) was 44.8% and 16.0%, respectively. Age and body mass index were significant determinants for OA both in any finger joint and in symmetrical DIP OA. The history of physical workload in women showed a positive association with OA in any finger joint. Smoking in men seemed to protect against symmetrical DIP OA. As adjusted for the determinants above, symmetrical DIP OA predicted mortality in women (relative risk (RR), 1.23; 95% confidence interval (95% CI) 1.01 to 1.51), but not in men (RR 0.89; 95% CI 0.68 to 1.16). In men, however, OA in any finger joint significantly predicted cardiovascular deaths (RR 1.42; 95% CI 1.05 to 1.92). Conclusion: OA in any finger joint and symmetrical DIP OA have different risk factor profiles and predict mortality in different patterns between men and women. PMID:12525385

  13. ANALYSIS OF AGED IN-HOME CARPETING TO DETERMINE THE DISTRIBUTION OF PESTICIDE RESIDUES BETWEEN DUST, CARPET, AND PAD COMPARTMENTS

    EPA Science Inventory

    This report presents results of a study to determine the distribution of pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) between dust and carpet components in aged carpeting. Carpeting in eight homes in the Research Triangle Area, which...

  14. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... in § 86.1826-08(d)(4). 3. Plot emissions (or catalyst inefficiency) versus aging time for each.... Plot the natural log (ln) of the slope of each best-fit line (determined in step 4) along the...

  15. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... in § 86.1826-08(d)(4). 3. Plot emissions (or catalyst inefficiency) versus aging time for each.... Plot the natural log (ln) of the slope of each best-fit line (determined in step 4) along the...

  16. 40 CFR Appendix Ix to Part 86 - Experimentally Determining the R-Factor for Bench Aging Durability Procedures

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... in § 86.1826-08(d)(4). 3. Plot emissions (or catalyst inefficiency) versus aging time for each.... Plot the natural log (ln) of the slope of each best-fit line (determined in step 4) along the...

  17. 76 FR 51458 - Culturally Significant Objects Imported for Exhibition Determinations: “Wonder of the Age: Master...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Wonder of the Age: Master Painters... Age: Master Painters of India, 1100-1900,'' imported from abroad for temporary exhibition within...

  18. Genomic and p16-specific DNA methylation of the mouse colon: elder age and dietary folate as interactive determinants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elder age and inadequate folate intake are strongly implicated as important risk factors for colon cancer and each is associated with altered DNA methylation. This study was designed to determine the effect of aging and dietary folate on select features of DNA methylation in the colon that are relev...

  19. Older age and dietary folate are determinants of genomic and p16-specific DNA methylation in mouse colon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Elder age and inadequate folate intake are strongly implicated as important risk factors for colon cancer, and each is associated with altered DNA methylation. This study was designed to determine the effect of aging and dietary folate on select features of DNA methylation in the colon that are rele...

  20. Rb-Sr age of the Civet Cat clast, 72255, 41. [radioactive age determination for lunar rocks

    NASA Technical Reports Server (NTRS)

    Compston, W.; Gray, C. M.

    1974-01-01

    Plagioclase rich clasts, orthopyroxene rich matrix, purified pyroxene, and plagioclase from the Civet Cat clast define a Rb-Sr isochron age of 4.18 + or - 0.04 x 10 to the 9th power yr and an initial Sr-87/Sr-86 ratio of 0.69922 + or - 0.00005. The fit of all data to the line is within error except for plagioclase 3, and blank corrections are essentially negligible. The decay constant used is 1.39 x 10 to the minus 11th power yr.

  1. Determining the age of CO2 Released From Mountain Birch Forest and Heath in Arctic Sweden

    NASA Astrophysics Data System (ADS)

    Hartley, I. P.; Garnett, M. H.; Hopkins, D. W.; Sommerkorn, M.; Wookey, P. A.

    2008-12-01

    Nuclear weapons testing released a large amount of 14C into the atmosphere during the mid 20th Century. This radiocarbon pulse provides a tracer that can be used to determine the age of C released from plants and soils. Such information is critical for predicting how terrestrial C storage will respond to global change. If respired CO2 is mainly modern, then respiration and photosynthesis are tightly coupled. In contrast, if older C is being mineralized then there is more potential for climate change to induce C loss. We carried out one of the first studies to measure seasonal variations in the 14C content of CO2 released from arctic ecosystems. Using molecular sieves, we trapped CO2 respired from a mountain birch forest and heath near Abisko, northern Sweden and measured 14C contents by accelerator mass spectrometry. CO2 was collected from both vegetated plots (control) and clipped and trenched plots (CT) on three occasions during the 2007 growing season. In addition, we used a new passive sampling technique to collect CO2 from the CT plots during winter 2007-2008. Assuming that the respired C was derived from post bomb sources (justifiable as the majority of each soil profile was enriched with bomb C), we estimated the age of the CO2 and how it changed during the year in response to changes in plant activity and key environmental drivers. On the heath, the mean age of the CO2 respired from the control plots increased from 4 to 6 years old during the growing season. The CO2 respired from the CT plots increased from 5 years old in early June to 11 years old by July, but then declined to 8 years old in September. The C released during winter was also 8 years old. In the Birch forest, the mean age of CO2 respired from the CT plots increased from 4 years old in late May to 8-9 years old during July and September. However, during winter, the CO2 released was >10 years old. In the control plots, the age of respired CO2 increased from being 1 year old in late May to 6

  2. Morphological, motor and technical determinants of fighting efficiency of Croatian female cadet age karate athletes.

    PubMed

    Jukić, Josefina; Katić, Ratko; Bala, Gustav

    2013-12-01

    The aim of this research was to determine the significance of morphological factors, factors of basic motor and specific motor abilities, and the factors of technical efficiency, on the karate fight success in Croatian female cadet karate athletes. With this purpose, the group of 18 anthropometric measures, 10 basic motor tests, 5 situational karate motor tests, the group of 8 evaluations of 6 basic karate techniques, and 2 karate kata performances was applied on the sample of 101 Croatian karateka aged 14 to 16. Inside the morphological area, the factor analysis isolated: Body mass and volume factor, Subcutaneous fat tissue factor, Longitudinal skeleton dimensionality factor, and Transversal fist dimensionality factor; in the basic motor area: General motor efficiency factor; in the situational motor area: General specific motor efficiency factor; in the area of karate technique performance evaluation: General technical efficiency factor. After that, the application of canonical discriminative analysis determined the differences between high and lower quality karate athletes in the overall area of the isolated factors. The discriminative function showed that high quality female karate athletes compared to those of lower quality differ the most in higher technical efficiency, higher basic and specific motor efficiency, while having somewhat less fat tissue and somewhat wider wrist and fist diameter. PMID:24611342

  3. Morphological, motor and technical determinants of fighting efficiency of Croatian female cadet age karate athletes.

    PubMed

    Jukić, Josefina; Katić, Ratko; Bala, Gustav

    2013-12-01

    The aim of this research was to determine the significance of morphological factors, factors of basic motor and specific motor abilities, and the factors of technical efficiency, on the karate fight success in Croatian female cadet karate athletes. With this purpose, the group of 18 anthropometric measures, 10 basic motor tests, 5 situational karate motor tests, the group of 8 evaluations of 6 basic karate techniques, and 2 karate kata performances was applied on the sample of 101 Croatian karateka aged 14 to 16. Inside the morphological area, the factor analysis isolated: Body mass and volume factor, Subcutaneous fat tissue factor, Longitudinal skeleton dimensionality factor, and Transversal fist dimensionality factor; in the basic motor area: General motor efficiency factor; in the situational motor area: General specific motor efficiency factor; in the area of karate technique performance evaluation: General technical efficiency factor. After that, the application of canonical discriminative analysis determined the differences between high and lower quality karate athletes in the overall area of the isolated factors. The discriminative function showed that high quality female karate athletes compared to those of lower quality differ the most in higher technical efficiency, higher basic and specific motor efficiency, while having somewhat less fat tissue and somewhat wider wrist and fist diameter.

  4. Stable Isotope Analysis of Extant Lamnoid Shark Centra: A New Tool in Age Determination?

    NASA Astrophysics Data System (ADS)

    Labs, J.

    2003-12-01

    The oxygen isotopes of fourteen vertebral centra from ten extant lamnoid sharks (including Carcharodon carcharias [great white], Isurus paucus [longfin mako], and Isurus oxyrinchus [shortfin mako]) were sampled and measured along the growth axis to determine the periodicity of incremental growth represented in the centra. As part of the internal (endochondral) skeleton, shark centra are composed initially of hyaline cartilage, which then secondarily ossifies during ontogeny forming calcified hydroxyapatite bone. The incremental growth of shark centra forms definite growth rings, with darker denser portions being deposited during slower growth times (i.e., winter) and lighter portions being deposited during more rapid growth (i.e., summer). Thus, shark centra, whether they are extant or extinct, are characterized by clearly delineated incremental growth couplets. The problem with this general rule is that there are several factors in which the growth of these couplets can vary depending upon physical environment (including temperature and water depth), food availability, and stress. The challenge for paleobiological interpretations is how to interpret the periodicity of this growth. It can generally be assumed that these bands are annual, but it is uncertain the extent to which exceptions to the rule occur. Stable isotopic analysis provides the potential to independently determine the periodicity of the growth increments and ultimately the ontogenetic age of an individual.

  5. A comparison of recharge rates in aquifers of the United States based on groundwater-age data

    USGS Publications Warehouse

    McMahon, P.B.; Plummer, L.N.; Böhlke, J.K.; Shapiro, S.D.; Hinkle, S.R.

    2011-01-01

    An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate groundwater recharge rates. Timescales of recharge were defined by 1,873 distributed tritium measurements and 102 radiocarbon measurements from 27 well networks. Recharge rates ranged from < 10 to 1,200 mm/yr in selected aquifers on the basis of measured vertical age distributions and assuming exponential age gradients. On a regional basis, recharge rates based on tracers of young groundwater exhibited a significant inverse correlation with mean annual air temperature and a significant positive correlation with mean annual precipitation. Comparison of recharge derived from groundwater ages with recharge derived from stream base-flow evaluation showed similar overall patterns but substantial local differences. Results from this compilation demonstrate that age-based recharge estimates can provide useful insights into spatial and temporal variability in recharge at a national scale and factors controlling that variability. Local age-based recharge estimates provide empirical data and process information that are needed for testing and improving more spatially complete model-based methods.

  6. A comparison of recharge rates in aquifers of the United States based on groundwater-age data

    NASA Astrophysics Data System (ADS)

    McMahon, P. B.; Plummer, L. N.; Böhlke, J. K.; Shapiro, S. D.; Hinkle, S. R.

    2011-06-01

    An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate groundwater recharge rates. Timescales of recharge were defined by 1,873 distributed tritium measurements and 102 radiocarbon measurements from 27 well networks. Recharge rates ranged from < 10 to 1,200 mm/yr in selected aquifers on the basis of measured vertical age distributions and assuming exponential age gradients. On a regional basis, recharge rates based on tracers of young groundwater exhibited a significant inverse correlation with mean annual air temperature and a significant positive correlation with mean annual precipitation. Comparison of recharge derived from groundwater ages with recharge derived from stream base-flow evaluation showed similar overall patterns but substantial local differences. Results from this compilation demonstrate that age-based recharge estimates can provide useful insights into spatial and temporal variability in recharge at a national scale and factors controlling that variability. Local age-based recharge estimates provide empirical data and process information that are needed for testing and improving more spatially complete model-based methods.

  7. 20 CFR 416.806 - Expedited adjudication based on documentary evidence of age.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Expedited adjudication based on documentary evidence of age. 416.806 Section 416.806 Employees' Benefits SOCIAL SECURITY ADMINISTRATION SUPPLEMENTAL... based on documentary evidence of age. Where documentary evidence of age recorded at least 3 years...

  8. Environmental determinants of asthma among school children aged 13-14 in and around Polokwane, Limpopo Province, South Africa.

    PubMed

    Maluleke, Kidi Rose; Worku, Zeleke

    2009-09-01

    Asthma has become a public health issue since the 1960's. Factors associated with asthma are environmental and genetic. This study is based on a random sample of 742 students aged 13-14 attending various schools at Polokwane, in the Province of Limpopo in South Africa. Survey logistic regression and multi-level analyses were used for data analysis. The study identifies three key determinants of asthma at the district, school and individual levels. The study shows that persistent cough (OR = 4.01), exposure to smoke at the household level (OR = 2.39) and lack of access to flush toileta at the household level (OR = 1.89) are key predictors of asthma in children. Variability at the level of districts accounts for 46% of total variance. Variability at the level of schools accounts for 33% of total variance.

  9. Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants – Interim Study FY13

    SciTech Connect

    Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.; Ramuhalli, Pradeep; Pardini, Allan F.; Tedeschi, Jonathan R.; Jones, Anthony M.

    2013-09-27

    The most important criterion for cable performance is its ability to withstand a design-basis accident. With nearly 1000 km of power, control, instrumentation, and other cables typically found in an NPP, it would be a significant undertaking to inspect all of the cables. Degradation of the cable jacket, electrical insulation, and other cable components is a key issue that is likely to affect the ability of the currently installed cables to operate safely and reliably for another 20 to 40 years beyond the initial operating life. The development of one or more nondestructive evaluation (NDE) techniques and supporting models that could assist in determining the remaining life expectancy of cables or their current degradation state would be of significant interest. The ability to nondestructively determine material and electrical properties of cable jackets and insulation without disturbing the cables or connections has been deemed essential. Currently, the only technique accepted by industry to measure cable elasticity (the gold standard for determining cable insulation degradation) is the indentation measurement. All other NDE techniques are used to find flaws in the cable and do not provide information to determine the current health or life expectancy. There is no single NDE technique that can satisfy all of the requirements needed for making a life-expectancy determination, but a wide range of methods have been evaluated for use in NPPs as part of a continuous evaluation program. The commonly used methods are indentation and visual inspection, but these are only suitable for easily accessible cables. Several NDE methodologies using electrical techniques are in use today for flaw detection but there are none that can predict the life of a cable. There are, however, several physical and chemical ptoperty changes in cable insulation as a result of thermal and radiation damage. In principle, these properties may be targets for advanced NDE methods to provide early

  10. Gestational age

    MedlinePlus

    Fetal age - gestational age; Gestation; Neonatal gestational age; Newborn gestational age ... Gestational age can be determined before or after birth. Before birth, your health care provider will use ultrasound to ...

  11. Lake Erie Yellow perch age estimation based on three structures: Precision, processing times, and management implications

    USGS Publications Warehouse

    Vandergoot, C.S.; Bur, M.T.; Powell, K.A.

    2008-01-01

    Yellow perch Perca flavescens support economically important recreational and commercial fisheries in Lake Erie and are intensively managed. Age estimation represents an integral component in the management of Lake Erie yellow perch stocks, as age-structured population models are used to set safe harvest levels on an annual basis. We compared the precision associated with yellow perch (N = 251) age estimates from scales, sagittal otoliths, and anal spine sections and evaluated the time required to process and estimate age from each structure. Three readers of varying experience estimated ages. The precision (mean coefficient of variation) of estimates among readers was 1% for sagittal otoliths, 5-6% for anal spines, and 11-13% for scales. Agreement rates among readers were 94-95% for otoliths, 71-76% for anal spines, and 45-50% for scales. Systematic age estimation differences were evident among scale and anal spine readers; less-experienced readers tended to underestimate ages of yellow perch older than age 4 relative to estimates made by an experienced reader. Mean scale age tended to underestimate ages of age-6 and older fish relative to otolith ages estimated by an experienced reader. Total annual mortality estimates based on scale ages were 20% higher than those based on otolith ages; mortality estimates based on anal spine ages were 4% higher than those based on otolith ages. Otoliths required more removal and preparation time than scales and anal spines, but age estimation time was substantially lower for otoliths than for the other two structures. We suggest the use of otoliths or anal spines for age estimation in yellow perch (regardless of length) from Lake Erie and other systems where precise age estimates are necessary, because age estimation errors resulting from the use of scales could generate incorrect management decisions. ?? Copyright by the American Fisheries Society 2008.

  12. Lattice parameter variations during aging in nickel-base superalloys

    NASA Technical Reports Server (NTRS)

    Nathal, M. V.; Mackay, R. A.; Garlick, R. G.

    1988-01-01

    The importance of the state of coherency on measurements of gamma/gamma-prime lattice mismatch has been experimentally demonstrated during aging at 1000 C of specimens of an alloy with composition Ni-(8.6)Cr-(5.3)Al-(10.1)Co-(11.7)W-(1.2)Ti-(0.7)Mo (wt pct). Lattice parameter measurements are given as a function of aging time, and the corresponding sample microstructures are presented. The results show that changes of the two phases during aging did not influence the lattice parameter measurements, indicating that aging specimens to produce a semicoherent gamma/gamma-prime structure provides a good approximation of the true, unconstrained lattice mismatch.

  13. Predicting successful aging in a population-based sample of georgia centenarians.

    PubMed

    Arnold, Jonathan; Dai, Jianliang; Nahapetyan, Lusine; Arte, Ankit; Johnson, Mary Ann; Hausman, Dorothy; Rodgers, Willard L; Hensley, Robert; Martin, Peter; Macdonald, Maurice; Davey, Adam; Siegler, Ilene C; Jazwinski, S Michal; Poon, Leonard W

    2010-01-01

    Used a population-based sample (Georgia Centenarian Study, GCS), to determine proportions of centenarians reaching 100 years as (1) survivors (43%) of chronic diseases first experienced between 0-80 years of age, (2) delayers (36%) with chronic diseases first experienced between 80-98 years of age, or (3) escapers (17%) with chronic diseases only at 98 years of age or older. Diseases fall into two morbidity profiles of 11 chronic diseases; one including cardiovascular disease, cancer, anemia, and osteoporosis, and another including dementia. Centenarians at risk for cancer in their lifetime tended to be escapers (73%), while those at risk for cardiovascular disease tended to be survivors (24%), delayers (39%), or escapers (32%). Approximately half (43%) of the centenarians did not experience dementia. Psychiatric disorders were positively associated with dementia, but prevalence of depression, anxiety, and psychoses did not differ significantly between centenarians and an octogenarian control group. However, centenarians were higher on the Geriatric Depression Scale (GDS) than octogenarians. Consistent with our model of developmental adaptation in aging, distal life events contribute to predicting survivorship outcome in which health status as survivor, delayer, or escaper appears as adaptation variables late in life. PMID:20885919

  14. Predicting successful aging in a population-based sample of georgia centenarians.

    PubMed

    Arnold, Jonathan; Dai, Jianliang; Nahapetyan, Lusine; Arte, Ankit; Johnson, Mary Ann; Hausman, Dorothy; Rodgers, Willard L; Hensley, Robert; Martin, Peter; Macdonald, Maurice; Davey, Adam; Siegler, Ilene C; Jazwinski, S Michal; Poon, Leonard W

    2010-01-01

    Used a population-based sample (Georgia Centenarian Study, GCS), to determine proportions of centenarians reaching 100 years as (1) survivors (43%) of chronic diseases first experienced between 0-80 years of age, (2) delayers (36%) with chronic diseases first experienced between 80-98 years of age, or (3) escapers (17%) with chronic diseases only at 98 years of age or older. Diseases fall into two morbidity profiles of 11 chronic diseases; one including cardiovascular disease, cancer, anemia, and osteoporosis, and another including dementia. Centenarians at risk for cancer in their lifetime tended to be escapers (73%), while those at risk for cardiovascular disease tended to be survivors (24%), delayers (39%), or escapers (32%). Approximately half (43%) of the centenarians did not experience dementia. Psychiatric disorders were positively associated with dementia, but prevalence of depression, anxiety, and psychoses did not differ significantly between centenarians and an octogenarian control group. However, centenarians were higher on the Geriatric Depression Scale (GDS) than octogenarians. Consistent with our model of developmental adaptation in aging, distal life events contribute to predicting survivorship outcome in which health status as survivor, delayer, or escaper appears as adaptation variables late in life.

  15. Waist circumference and insulin resistance: a community based cross sectional study on reproductive aged Iranian women

    PubMed Central

    2011-01-01

    Background Although the positive relationship between insulin resistance (IR) and central obesity is well known, the direct relationship between waist circumference and IR is not clear yet and there is no consensus regarding the cut off value for waist circumference as a surrogate index for central obesity. The present study was aimed to determine the optimal cut-off value of waist circumference (WC) for predicting IR in reproductive aged Iranian women. Methods Using the stratified, multistage probability cluster sampling method 1036 women were randomly selected from among reproductive aged women of different geographic regions of Iran. Following implementation of exclusion criteria, complete data for 907 women remained for analysis. Insulin resistance was evaluated by the homeostasis model assessment (HOMA-IR) and its cut off value was defined as the 95th percentile of HOMA-IR value for 129 subjects, without any metabolic abnormality. The optimal cut-off of WC in relation to HOMA-IR was calculated based on the receiver operating characteristics (ROC) curve analysis using the Youden index and the area under curve (AUC). Results The mean age of the total sample of 907 subjects was 34.4 ± 7.6 years (range, 18 - 45 years). After adjustment for age the odds ratios (OR) of elevated HOMA-IR were progressively higher with increasing levels of waist circumference; the age adjusted OR of IR for women with WC > 95 cm in comparison to those subjects with WC < 80 cm, was 9.5 (95% CI 5.6-16.1). The optimal cutoff value for WC predicting IR was 88.5 cm; with a sensitivity and specificity of 71% and 64%, respectively. Conclusions Waist circumference is directly related to insulin resistance and the optimal cut-off value for waist circumference reflecting insulin resistance is considered to be 88.5 cm for reproductive aged Iranian women. PMID:21831271

  16. Age estimation in forensic anthropology: quantification of observer error in phase versus component-based methods.

    PubMed

    Shirley, Natalie R; Ramirez Montes, Paula Andrea

    2015-01-01

    The purpose of this study was to assess observer error in phase versus component-based scoring systems used to develop age estimation methods in forensic anthropology. A method preferred by forensic anthropologists in the AAFS was selected for this evaluation (the Suchey-Brooks method for the pubic symphysis). The Suchey-Brooks descriptions were used to develop a corresponding component-based scoring system for comparison. Several commonly used reliability statistics (kappa, weighted kappa, and the intraclass correlation coefficient) were calculated to assess observer agreement between two observers and to evaluate the efficacy of each of these statistics for this study. The linear weighted kappa was determined to be the most suitable measure of observer agreement. The results show that a component-based system offers the possibility for more objective scoring than a phase system as long as the coding possibilities for each trait do not exceed three states of expression, each with as little overlap as possible.

  17. A comparison between voxel-based cortical thickness and voxel-based morphometry in normal aging.

    PubMed

    Hutton, Chloe; Draganski, Bogdan; Ashburner, John; Weiskopf, Nikolaus

    2009-11-01

    The morphology of cortical grey matter is commonly assessed using T1-weighted MRI together with automated computerised methods such as voxel-based morphometry (VBM) and cortical thickness measures. In the presented study we investigate how grey matter changes identified using voxel-based cortical thickness (VBCT) measures compare with local grey matter volume changes identified using VBM. We use data from a healthy aging population to perform the comparison, focusing on brain regions where age-related changes have been observed in previous studies. Our results show that overall, in healthy aging, VBCT and VBM yield very consistent results but VBCT provides a more sensitive measure of age-associated decline in grey matter compared with VBM. Our findings suggest that while VBCT selectively investigates cortical thickness, VBM provides a mixed measure of grey matter including cortical surface area or cortical folding, as well as cortical thickness. We therefore propose that used together, these techniques can separate the underlying grey matter changes, highlighting the utility of combining these complementary methods. PMID:19559801

  18. Estimation of age based on tooth cementum annulations: A comparative study using light, polarized, and phase contrast microscopy

    PubMed Central

    Kaur, Prabhpreet; Astekar, Madhusudan; Singh, Jappreet; Arora, Karandeep Singh; Bhalla, Gagandeep

    2015-01-01

    Context: The identification of living or deceased persons using unique traits and characteristics of the teeth and jaws is a cornerstone of forensic science. Teeth have been used to estimate age both in the young and old, as well as in the living and dead. Gradual structural changes in teeth throughout life are the basis for age estimation. Tooth cementum annulation (TCA) is a microscopic method for the determination of an individual's age based on the analysis of incremental lines of cementum. Aim: To compare ages estimated using incremental lines of cementum as visualized by bright field microscopy, polarized microscopy, and phase contrast microscopy with the actual age of subject and to determine accuracy and feasibility of the method used. Materials and Methods: Cementum annulations of 60 permanent teeth were analyzed after longitudinal ground sections were made in the mesiodistal plane. The incremental lines were counted manually using a light, polarized and phase contrast microscopy. Ages were estimated and then compared with the actual age of individual. Statistical Analysis: Analysis of variance (ANOVA), Student's t-test, the Pearson product-moment corre (PPMCC) and regression analysis were performed. Results: PPMCC value r = 0.347, 0.542 and 0.989 were obtained using light, polarized and phase contrast microscopy methods respectively. Conclusion: It was concluded that incremental lines of cementum were most clearly visible under a phase contrast microscope, followed by a polarized microscope, and then a light microscope when used for age estimation. PMID:26816462

  19. Highway crash rates and age-related driver limitations: Literature review and evaluation of data bases

    SciTech Connect

    Hu, P.S.; Young, J.R.; Lu, An

    1993-08-01

    American society is undergoing a major demographic transformation that is resulting in a larger proportion of older individuals in the population. Moreover, recent travel surveys show that an increasing number of older individuals are licensed to drive and that they drive more than their same age cohort a decade ago. However, they continue to take shorter trips than younger drivers and they avoid driving during congested hours. This recent demographic transformation in our society, the graying of America, coupled with the increasing mobility of the older population impose a serious highway safety issue that cannot be overlooked. Some of the major concerns are the identification of ``high-risk`` older drivers and the establishment of licensing guidelines and procedures that are based on conclusive scientific evidence. Oak Ridge National Laboratory`s (ORNL) objectives in this project can be characterized by the following tasks: Review and evaluate the 1980 American Association of Motor Vehicle Administrators (AAMVA) and National Highway Traffic Safety Administration (NHTSA) licensing guidelines. Determine whether the license restriction recommended in the 1980 AAMVA and NHTSA guidelines was based on scientific evidence or on judgement of medical advisors. Identify in the scientific literature any medical conditions which are found to be highly associated with highway crashes, and which are not mentioned in the 1980 guidelines. Summarize States` current licensing practices for drivers with age-related physical and mental limitations. Identify potential data sources to establish conclusive evidence on age-related functional impairments and highway crashes.

  20. Determination of rain age via {gamma} rays from accreted radon progeny

    SciTech Connect

    Greenfield, M. B.; Ito, N.; Iwata, A.; Kubo, K.; Ishigaki, M.; Komura, K.

    2008-10-01

    The relative {gamma} ray activities from {sup 214}Pb and {sup 214}Bi condensed from precipitation are used to determine its 'age', the average time the accreted activity has been removed from secular equilibrium. A verifiable assumption that radon progeny on/in the surface/volume of droplets mostly remains in secular equilibrium until they begin their descent, enables estimates of their transit times to ground of typically a few tens of minutes. This agrees well with the time expected for the activity on the surface of droplets to reach the ground from heights of a few kilometers. The half lives of {gamma} activities from {sup 214}Bi and {sup 214}Pb, 19.7 and 26.9 min, respectively, are on the same scale as transit time to ground and close enough to each other to measure ratios of activities from secular equilibrium (1.00) to transient equilibrium (3.88) within a few hundreds of minutes. The ratio of {gamma} count rates is independent of knowledge of either initial activity or any systematic errors and thus limited only by the uncertainty from counting statistics, which from condensates of 5-30 l of rain viewed with 2{pi} solid angle by a 50% efficient, high-resolution Ge detector is only a few percent. These ratios fit extremely well to known theoretical curves, which cannot only be used to date rain but can also be extrapolated backward to determine radon progeny activities in rain prior to its descent, knowledge of which may facilitate further studies using radon progeny as tracers.

  1. Cobalt-based age models of pelagic clay in the South Pacific Gyre

    NASA Astrophysics Data System (ADS)

    Dunlea, Ann G.; Murray, Richard W.; Sauvage, Justine; Pockalny, Robert A.; Spivack, Arthur J.; Harris, Robert N.; D'Hondt, Steven

    2015-09-01

    Dating pelagic clay can be a challenge due to its slow sedimentation rate, post-depositional alteration, and lack of biogenic deposition. Co-based dating techniques have the potential to create age models in pelagic clay under the assumption that the flux of non-detrital Co to the seafloor is spatially and temporally constant, resulting in the non-detrital Co concentrations being inversely proportional to sedimentation rate. We apply a Co-based method to the pelagic clay sequences from Sites U1365, U1366, U1369, and U1370 drilled during Integrated Ocean Drilling Program (IODP) Expedition 329 in the South Pacific Gyre. We distinguished non-detrital Co from detrital Co using multivariate statistical partitioning techniques. We found that the non-detrital flux of Co at Site U1370 is approximately twice as high as that at the other sites, implying that the non-detrital Co flux is not regionally constant. This regional variation reflects the heterogeneous distribution of Co in the water column, as is observed in the present day. We present an improved approach to Co-based age modeling throughout the South Pacific Gyre and determine that the Co-based method can effectively date oxygenated pelagic clay deposited in the distal open ocean, but is less reliable for deposition closer to continents. When extending the method to geologically old sediment, it is important to consider the paleolocation of a given site to ensure these conditions are met.

  2. Determining patient preferences in the management of neovascular age-related macular degeneration: a conjoint analysis.

    PubMed

    Baxter, J M; Fotheringham, A J; Foss, A J E

    2016-05-01

    PurposeTo determine the opinions from a patient perspective on relevant variables in the delivery of treatment for neovascular age-related macular degeneration (nAMD).MethodsPilot interviews with patients and doctors were conducted to identify what variables in the provision of a nAMD service were important. This led to the generation of two sets of scenario options. Subsequently 100 patients undergoing active treatment for nAMD in the National Health Service University Hospital, United Kingdom underwent interview assessment. They were asked to rank their preferences for provision of their care with reference to these two sets of scenario options. Using conjoint analysis, percentage preferences, and utility scores for each variable in each scenario design were calculated.ResultsNinety-five patients completed the preference ranking for both scenarios. Eight patients ranked worse vision as preferable to better vision and were excluded on the basis that they had not understood the task. The results of the remaining 87 patients are presented. The most important factor to patients was having good vision, followed by a one-stop service and less frequent follow up. The least important factors were label status of the drug, cost to the health service, and grade of the injector.ConclusionPatients regard good vision and minimal visits to the hospital above the status of injector, label status of drug, or cost to the NHS.

  3. Feedback-based versus observational classification learning in healthy aging and Parkinson's disease.

    PubMed

    Schmitt-Eliassen, Julia; Ferstl, Roman; Wiesner, Christian; Deuschl, Günther; Witt, Karsten

    2007-04-20

    Previous studies underline the role of dopamine in cognitive reinforcement learning. This has been demonstrated by a striatal involvement in feedback-based probabilistic classification learning. In order to determine to which extent the dopaminergic loss of Parkinson's disease and aging affects the feedback aspect in classification learning, we applied two versions of the same visual classification task. One version had to be learnt by trial-by-trial feedback, the other by observing the correct assignment of stimulus and category. Performance was evaluated in test blocks that were identical under the feedback and the observational conditions. There were 31 patients with Parkinson's disease (PD), 30 older controls and 20 younger controls tested. The results show that younger healthy participants perform better than older participants in the classification task and this difference significantly interacts with the learning condition: both groups show nearly the same level of performance under the observational condition but younger participants show a better performance than older ones under the feedback condition. In contrast, PD patients and older controls did not differ in their performance in the classification task; both groups performed better under the observational than under the feedback condition. These results demonstrate that healthy aging affects feedback-based learning but does not affect learning by observation. The fact that PD patients showed no additional deficit in feedback-based learning is an indication that the loss of dopamine does not play the key role under the feedback condition of our classification task. This finding questions the general role of the striatum in feedback-based learning and demonstrates that healthy aging particularly affects feedback-based learning.

  4. Biometry based ageing of nestling Indian Spotted Owlets ( Athene brama brama)

    PubMed Central

    Pande, Satish; Pawashe, Amit; Mahajan, Mahadeo N.; Mahabal, Anil; Yosef, Reuven; Dahanukar, Neelesh

    2011-01-01

    Abstract Biometric analysis helps in sex differentiation, understanding development and for studies of avian biology such as foraging ecology, evolutionary ecology, and survivorship. We suggest that biometry can also be a reliable, practical and inexpensive tool to determine the age of nestlings in the field by non-invasive methods. As an example we studied the biometry of wing, culmen, talon, tarsus and body mass of nestling southern Indian Spotted Owlets (Athene brama brama). Based on the growth pattern analysis using logistic growth model, discriminant analysis and CHAID (Chi-squared Automatic Interaction Detection) based decision tree, we show that biometry of nestling Spotted Owlets is an easy, reliable and inexpensive method to determine nestling age and to assess growth rate and relative nutritional status. These biometric parameters also allow us to predict their ability to initiate first flight from the nest site. This method is described here for the first time and we postulate that such charts can be devised for other avian species as well, so as to assist conservation biologists and bird rescuers. PMID:22140335

  5. Biometry based ageing of nestling Indian Spotted Owlets ( Athene brama brama).

    PubMed

    Pande, Satish; Pawashe, Amit; Mahajan, Mahadeo N; Mahabal, Anil; Yosef, Reuven; Dahanukar, Neelesh

    2011-01-01

    Biometric analysis helps in sex differentiation, understanding development and for studies of avian biology such as foraging ecology, evolutionary ecology, and survivorship. We suggest that biometry can also be a reliable, practical and inexpensive tool to determine the age of nestlings in the field by non-invasive methods. As an example we studied the biometry of wing, culmen, talon, tarsus and body mass of nestling southern Indian Spotted Owlets (Athene brama brama). Based on the growth pattern analysis using logistic growth model, discriminant analysis and CHAID (Chi-squared Automatic Interaction Detection) based decision tree, we show that biometry of nestling Spotted Owlets is an easy, reliable and inexpensive method to determine nestling age and to assess growth rate and relative nutritional status. These biometric parameters also allow us to predict their ability to initiate first flight from the nest site. This method is described here for the first time and we postulate that such charts can be devised for other avian species as well, so as to assist conservation biologists and bird rescuers.

  6. Determinants of Institutional Delivery among Childbearing Age Women in Western Ethiopia, 2013: Unmatched Case Control Study

    PubMed Central

    Feyissa, Tesfaye Regassa; Genemo, Gebi Agero

    2014-01-01

    Background Place of delivery is a crucial factor which affects the health and wellbeing of the mother and newborn. Institutional delivery helps the women to access skilled assistance, drugs, equipment, and referral transport. Even though 34% of pregnant women received at least one antenatal care from a skilled provider in Ethiopia by 2013, institutional delivery was 10%. The main objective of the study was to assess determinants of institutional delivery in Western Ethiopia. Methods Retrospective unmatched case control study design was used to assess determinants of institutional delivery in Western Ethiopia from September to October 2013. A total of 320 respondents from six districts of East Wollega zone, West Ethiopia were included. Data were collected using pretested and structured questionnaires. Data were entered and cleaned by Epi-info then exported and analyzed using SPSS software. Statistical significance was determined through a 95% confidence level. Results Education [Adjusted Odds Ratio (AOR) (95% Confidence Interval (CI)) = 2.754(1.510–8.911)], family size [AOR (95% CI) = .454(.209–.984)], residence [AOR (95% CI) = 3.822 (1.766–8.272)] were important predictors of place of delivery. Four or more antenatal care [(ANC) (AOR (95% CI) = 2.914(1.105–7.682)], birth order [(AOR (95% CI) = .136(.054–.344), age at last delivery [(AOR (95% CI) = 9.995(2.101–47.556)], birth preparedness [AOR (95% CI) = 6.957(2.422–19.987)], duration of labour [AOR (95% CI) = 3.541(1.732–7.239)] were significantly associated with institutional delivery. Moreover service related factors such as distance from health institutions [AOR (95% CI) = .665(.173–.954)], respondents’ awareness of skill of health care professionals [AOR (95% CI) = 2.454 (1.663–6.255)], mode of transportations [AOR (95% CI) = .258(.122–.549)] were significantly associated with institutional delivery. Conclusions and Recommendations Policy

  7. Brain-Based Teaching in the Digital Age

    ERIC Educational Resources Information Center

    Sprenger, Marilee

    2010-01-01

    In the digital age, your students have the ways, means, and speed to gather any information they want. But they need your guidance more than ever. Discover how digital technology is actually changing your students' brains. Learn why this creates new obstacles for teachers, but also opens up potential new pathways for learning. You will understand…

  8. Exceptional Brain Aging in a Rural Population-Based Cohort

    ERIC Educational Resources Information Center

    Kaye, Jeffrey; Michael, Yvonne; Calvert, James; Leahy, Marjorie; Crawford, Debbie; Kramer, Patricia

    2009-01-01

    Context: The 2000 US Census identified 50,454 Americans over the age of 100. Increased longevity is only of benefit if accompanied by maintenance of independence and quality of life. Little is known about the prevalence of dementia and other disabling conditions among rural centenarians although this information is important to clinicians caring…

  9. Shoulder muscle strengh in asyntomatic patients, according to age, sex and method of determination

    PubMed Central

    Arcuri, Francisco; Barclay, Fernando; Nacul, Iván

    2015-01-01

    Objective: Determine the normal value of shoulder muscle strengh, in an adult population divided in six groups between 20 to 86 years, without known shoulder pathology. Materials and Methods: 523 individuals, 1046 shoulders, had their muscle strengh evaluated in two different positions, in 90 abduction and 90º fowarf flexion in the scapular plane. Three measurements were performed and the aveage one was recorded. Patiens with known shoulder pathology, reumathoid diseases, cancer were excluded. The patients were divided in six groups according to age, from 20 to 29 (68 patients), 30 to 39 (92 patients), 40 to 49 (109 patients), 50 to 59 (103 patients), 60 to 69 (91 patients) and 70 to 90 (60 patients). The strengh eas measured in pounds. Results: Average mucle strengh was 17,64 at the scapular plane and 16,82 lb at 90ª (p<0,0001)For the right shoulder, the average muscle strengh of the second decade group was 22 lb at scapular plane and 20,73 at 90º. The third decade was 19,93 and 18,50 respectively. The fouth decade values were 20,45 and 19,58, on the fifth decade 17,83 and 17,07. On the sixth decade was 15,57 and 15,23 and for the seventh decade was 11,40 and 11 lb respectively. The values for the left shoulder were for the second decade 21,53 om the scapular plane and 20,53 at 90º. On the third decade were 19,33 and 18,17, on the fourth decade 19,62 and 18,95, on the fifth decade were 16,8 and 16,2 , on the sixth decade 15,57 and 15,23. And for the final group 11,4 and 11 lb. Significant differences were seen between both shoulders ,sex (p<0,0001), position of the arm at time of measure (p0,0001), dominace (p0,001) Conclusion: The objective measurement of the muscle strengh of the shoulder varies significantly with age, sex and position of the arm at time of measure, putting in dout the validity of the contralateral shoulder as a value to compare against.

  10. Lifestyle and Socioeconomic Determinants of Multimorbidity Patterns among Mid-Aged Women: A Longitudinal Study

    PubMed Central

    Jackson, Caroline A.; Dobson, Annette J.; Tooth, Leigh R.; Mishra, Gita D.

    2016-01-01

    Background Little is known about patterns of associative multimorbidity and their aetiology. We aimed to identify patterns of associative multimorbidity among mid-aged women and the lifestyle and socioeconomic factors associated with their development. Methods Participants were from the Australian Longitudinal Study on Women’s Health. We included 4896 women born 1946–51, without multimorbidity in 1998. We identified multimorbidity patterns at survey 6 (2010) using factor analysis, and related these patterns to baseline lifestyle and socioeconomic factors using logistic regression. We dichotomised factor scores and determined odds ratios (ORs) with 95% confidence intervals (CIs) for associations between characteristics and odds of a high versus low factor score. Results We identified five multimorbidity patterns: psychosomatic; musculoskeletal; cardiometabolic; cancer; and respiratory. Overweight and obesity were respectively associated with increased odds of having a high score for the musculoskeletal (adjusted ORs 1.45 [95% CI 1.23, 1.70] and 2.14 [95% CI 1.75, 2.60]) and cardiometabolic (adjusted ORs 1.53 [95% CI 1.31, 1.79] and 2.46 [95% CI 2.02, 2.98]) patterns. Physical inactivity was associated with increased odds of a high score for the psychosomatic, musculoskeletal and cancer patterns (adjusted ORs 1.41 [95% CI 1.13, 1.76]; 1.39 [95% CI 1.11, 1.74]; and 1.35 [95% CI 1.08, 1.69]). Smoking was associated with increased odds of a high score for the respiratory pattern. Education and ability to manage on income were associated with increased odds of a high score for the psychosomatic pattern (adjusted ORs 1.34 [95% CI 1.03, 1.75] and 1.73 [95% CI 1.37, 1.28], respectively) and musculoskeletal pattern (adjusted ORs 1.43 [95% CI 1.10, 1.87] and 1.38 [1.09, 1.75], respectively). Conclusions Distinct multimorbidity patterns can be identified among mid-aged women. Social inequality, physical activity and BMI are risk factors common to multiple patterns and are

  11. Determinants of caregivers’ vaccination intention with respect to child age group: a cross-sectional survey in South Korea

    PubMed Central

    Paek, Hye-Jin; Shin, Kyung-Ah; Park, Kisoo

    2015-01-01

    Objective This study examined how knowledge, risk perception, health beliefs and multidimensional health locus of control (HLC) were associated with caregivers’ intention to vaccinate their child, and how these associations varied across child age groups. Setting South Korea. Methods The cross-sectional survey was conducted via a face-to-face interview among 1017 nationally representative caregivers who had children aged 12 or younger. The outcome variable was caregivers’ intention to vaccinate their children. Results Hierarchical regression analysis indicated that risk perception was negatively associated with vaccination intention only among the age group 4–6 (β=−0.127, p<0.05). Perceived benefit was the only significant predictor of the outcome variables for all three age groups. In contrast, perceived barrier was negatively related to vaccination intention only among the age group 7–12 (β=−0.104, p<0.05). Internal HLC was positively related to vaccination intention only among the age group 7–12 (β=0.151, p<0.001), while chance HLC was negatively related to vaccination intention only among the age group 0–3 (β=−0.121, p<0.05). Conclusions This study identifies key vaccination intention determinants that are differentially associated with caregivers’ children's age groups. To improve vaccination rates, it suggests the need for strategies tailored to children's age. PMID:26408283

  12. Aging and physical fitness are more important than obesity in determining exercise-induced generation of GH.

    PubMed

    Holt, R I; Webb, E; Pentecost, C; Sönksen, P H

    2001-12-01

    Exercise is a potent stimulus for GH secretion. Aging and obesity are associated with a diminution of GH secretion. We wanted to determine whether age or fat mass is more important in regulating the GH response to exercise. Four groups of healthy men were studied: seven lean young men [age, <40 yr; body mass index (BMI), <25 kg/m(2)], six overweight young men (age, <40 yr; BMI, >27.5), seven lean older men (age, >60 yr; BMI, <25), and 6 overweight older men (age, 60 yr; BMI, >27.5). The men performed a maximal exercise test. GH secretion was higher in the younger men than in the older men. Peak GH was higher in the older lean men than in the older overweight men. There was no difference between the young groups. Fitness correlated negatively with age and positively with peak GH. In young men, there was no relation between BMI, bioimpedance, or leptin and GH secretion. In contrast, in older men there was an inverse correlation between measures of fat mass and GH secretion. Age and physical fitness are more important than body fat in regulating exercise-induced GH secretion. These findings have important clinical implications if we are to prevent the frailty and morbidity associated with aging.

  13. Sex-Based Memory Advantages and Cognitive Aging: A Challenge to the Cognitive Reserve Construct?

    PubMed Central

    Caselli, Richard J.; Dueck, Amylou C.; Locke, Dona E.C.; Baxter, Leslie C.; Woodruff, Bryan K.; Geda, Yonas E.

    2016-01-01

    Education and related proxies for cognitive reserve (CR) are confounded by associations with environmental factors that correlate with cerebrovascular disease possibly explaining discrepancies between studies examining their relationships to cognitive aging and dementia. In contrast, sex-related memory differences may be a better proxy. Since they arise developmentally, they are less likely to reflect environmental confounds. Women outperform men on verbal and men generally outperform women on visuospatial memory tasks. Furthermore, memory declines during the preclinical stage of AD, when it is clinically indistinguishable from normal aging. To determine whether CR mitigates age-related memory decline, we examined the effects of gender and APOE genotype on longitudinal memory performances. Memory decline was assessed in a cohort of healthy men and women enriched for APOE ε4 who completed two verbal [Rey Auditory Verbal Learning Test (AVLT), Buschke Selective Reminding Test (SRT)] and two visuospatial [Rey-Osterrieth Complex Figure Test (CFT), and Benton Visual Retention Test (VRT)] memory tests, as well as in a separate larger and older cohort [National Alzheimer’s Coordinating Center (NACC)] who completed a verbal memory test (Logical Memory). Age-related memory decline was accelerated in APOE ε4 carriers on all verbal memory measures (AVLT, p = .03; SRT p<.001; logical memory p<.001) and on the VRT p = .006. Baseline sex associated differences were retained over time, but no sex differences in rate of decline were found for any measure in either cohort. Sex-based memory advantage does not mitigate age-related memory decline in either APOE ε4 carriers or non-carriers. PMID:25665170

  14. Age determination of the world's oldest movable metal types through measuring the "meog" using AMS

    NASA Astrophysics Data System (ADS)

    Hong, W.; Lee, S. C.; Park, J. H.; Park, G.; Sung, K. H.; Lee, J. G.; Nam, K. H.

    2015-10-01

    The fabrication year of a set of movable metal types that were thought to be used for printing "Jeungdoga" was investigated. Since the types were made from bronze and did not contain carbon, an organic black ink called "meog" was collected from the type surfaces to quantify their ages. The meog samples were collected from 34 metal types, and 27 ages were obtained. The youngest age was 798 ± 44 yrBP, and the oldest reasonable age was 1166 ± 43 yrBP. The weighted average after eliminating ages with poor statistics was 950 ± 28 yrBP. This age is 300 years older than that of the Jikji (AD 1377), which is a Buddhist document recognized as the world's oldest document printed using metal types, and also older than that of the Gutenberg bible (AD 1450).

  15. Structural scene analysis and content-based image retrieval applied to bone age assessment

    NASA Astrophysics Data System (ADS)

    Fischer, Benedikt; Brosig, André; Deserno, Thomas M.; Ott, Bastian; Günther, Rolf W.

    2009-02-01

    Radiological bone age assessment is based on global or local image regions of interest (ROI), such as epiphyseal regions or the area of carpal bones. Usually, these regions are compared to a standardized reference and a score determining the skeletal maturity is calculated. For computer-assisted diagnosis, automatic ROI extraction is done so far by heuristic approaches. In this work, we apply a high-level approach of scene analysis for knowledge-based ROI segmentation. Based on a set of 100 reference images from the IRMA database, a so called structural prototype (SP) is trained. In this graph-based structure, the 14 phalanges and 5 metacarpal bones are represented by nodes, with associated location, shape, as well as texture parameters modeled by Gaussians. Accordingly, the Gaussians describing the relative positions, relative orientation, and other relative parameters between two nodes are associated to the edges. Thereafter, segmentation of a hand radiograph is done in several steps: (i) a multi-scale region merging scheme is applied to extract visually prominent regions; (ii) a graph/sub-graph matching to the SP robustly identifies a subset of the 19 bones; (iii) the SP is registered to the current image for complete scene-reconstruction (iv) the epiphyseal regions are extracted from the reconstructed scene. The evaluation is based on 137 images of Caucasian males from the USC hand atlas. Overall, an error rate of 32% is achieved, for the 6 middle distal and medial/distal epiphyses, 23% of all extractions need adjustments. On average 9.58 of the 14 epiphyseal regions were extracted successfully per image. This is promising for further use in content-based image retrieval (CBIR) and CBIR-based automatic bone age assessment.

  16. Hormonal determinants of the severity of andropausal and depressive symptoms in middle-aged and elderly men with prediabetes.

    PubMed

    Rabijewski, Michał; Papierska, Lucyna; Kuczerowski, Roman; Piątkiewicz, Paweł

    2015-01-01

    Andropausal and depressive symptoms are common in aging males and may be associated with hormone deficiency. We investigated the severity of andropausal and depressive symptoms, as well as their hormonal determinants, in 196 middle-aged and elderly men (age range: 40-80 years) with prediabetes (PD) and in 184 healthy peers. PD was diagnosed according to the definition of the American Diabetes Association. The severity of andropausal and depressive symptoms was assessed using the Aging Males' Symptoms Rating Scale and the Self-Rating Depression Scale. Total testosterone (TT), calculated free testosterone (cFT), dehydroepiandrosterone sulfate (DHEAS), and insulin-like growth factor 1 (IGF-1) were measured. The prevalence of andropausal syndrome in men with PD was significantly higher than that in healthy men (35% vs 11%, respectively). In men with PD aged 40-59 years, the severity of sexual, psychological, and all andropausal symptoms was greater than in healthy peers, while in elderly men (60-80 years), only the severity of psychological symptoms was greater than in healthy peers. The severity of depressive symptoms in the middle-aged men with PD was greater than in healthy peers, while the severity of depressive symptoms in elderly men with PD and healthy peers was similar. The higher prevalence of andropausal symptoms was independently associated with cFT and IGF-1 in middle-aged men and with TT and DHEAS in elderly men with PD. The more severe depression symptoms were associated with low TT and DHEAS in middle-aged men and with low cFT and DHEAS in elderly men with PD. In conclusion, the prevalence of andropausal symptoms, especially psychological, was higher in prediabetic patients as compared to healthy men, while the severity of depressive symptoms was higher only in middle-aged men with PD. Hormonal determinants of andropausal and depressive symptoms are different in middle-aged and elderly patients, but endocrine tests are necessary in all men with PD.

  17. Estimating carbon stocks based on forest volume-age relationship

    NASA Astrophysics Data System (ADS)

    Hangnan, Y.; Lee, W.; Son, Y.; Kwak, D.; Nam, K.; Moonil, K.; Taesung, K.

    2012-12-01

    This research attempted to estimate potential change of forest carbon stocks between 2010 and 2110 in South Korea, using the forest cover map and National Forest Inventory (NFI) data. Allometric functions (logistic regression models) of volume-age relationships were developed to estimate carbon stock change during upcoming 100 years for Pinus densiflora, Pinus koraiensis, Pinus rigida, Larix kaempferi,and Quercus spp. The current forest volume was estimated with the developed regression model and 4th forest cover map. The future volume was predicted by developed volume-age models with adding n years to current age. As a result, we found that the total forest volume would increase from 126.89 m^3/ha to 246.61 m^3/ha and the carbon stocks would increase from 90.55 Mg C ha^(-1) to 174.62 Mg C ha^(-1) during 100 years when current forest remains unchanged. The carbon stocks would increase by approximately 0.84 Mg C ha^(-1) yr^(-1), which has high value if considering other northern countries' (Canada, Russia, China) -0.10 ~ 0.28 Mg C ha^(-1) yr^(-1) in pervious study. This can be attributed to the fact that mixed forest and bamboo forest in this study did not considered. Moreover, it must be influenced by that the change of carbon stocks was estimated without the consideration of mortality, thinning, and tree species' change in this study. ;

  18. A Detached Eclipsing Binary near the Turnoff of the Open Cluster NGC 6819 and Determining Age Using Kepler

    NASA Astrophysics Data System (ADS)

    Brewer, Lauren; Sandquist, E. L.; Mathieu, R. D.; Milliman, K.; Geller, A. M.; Jeffries, M.; Orosz, J. A.; Brogaard, K. F.; Platais, I.; Bruntt, H.; Grundahl, F.; Stello, D.; Frandsen, S.

    2013-01-01

    Measurements of the mass and radius of detached eclipsing binaries (DEB) can be used to accurately determine the ages of clusters if an eclipsing star is evolved enough and sits near the cluster turnoff on the color-magnitude diagram (CMD). Multiple DEBs in a cluster can constrain the age even more tightly, and can also lead to inferences about chemical composition (such as helium abundance). As part of our study of the old 2.5 Gyr) open cluster NGC 6819 in the Kepler field, we present results for the DEB Auner 665 (WOCS 24009) with a short period of 3.6 days. We make use of photometric observations from the Kepler spacecraft and from the 1 m telescope at Mount Laguna Observatory in B, V, Rc, and Ic. Radial velocities were measured as part of a long-term study of the cluster (e.g., Hole et al. 2009) using the WIYN 3.5-meter telescope. A665 is a triple-lined system, and we verify that the brightest star is physically orbiting the eclipsing binary based on radial velocities and eclipse timing variations. The stars that make up the detached eclipsing binary are almost identical in temperature, with eclipses that are only clearly distinguishable using Kepler photometry. A new astrometric study of NGC 6819 confirms the cluster membership probability of A665 at a level of P=99%. Ultimately, we will compare the masses and radii obtained with theoretical isochrones and analyze the derived age of NGC 6819, which can also be used to improve stellar theoretical models with better constraints in the mass-radius plane. Our target is to reduce the uncertainty on the cluster age to less than 10% using results from A665 and other known DEBs. The results for this system will also help produce a valuable test of the asteroseismic mass estimates for giant stars in the cluster (Stello et al. 2011). We gratefully acknowledge funding from the National Science Foundation under grant AST-0908536 and NASA under grants NNX11AC76G and NNX12AC88G.

  19. Traditional versus Non-Traditional University Students: Does Age Determine Learning?

    ERIC Educational Resources Information Center

    Christian, Maria E.

    This study investigated how students over the age of 30--nontraditional students--performed in the university setting compared to traditional students (under age 30). Overall classroom performance was evaluated by teacher-made assessments for the two groups of students, who were enrolled in an undergraduate technical writing course during the…

  20. Using naturally occurring radionuclides to determine drinking water age in a community water system

    DOE PAGES

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n =more » 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

  1. Using Naturally Occurring Radionuclides To Determine Drinking Water Age in a Community Water System.

    PubMed

    Waples, James T; Bordewyk, Jason K; Knesting, Kristina M; Orlandini, Kent A

    2015-08-18

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of (90)Y/(90)Sr and (234)Th/(238)U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r(2) = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r(2) = 0.996, n = 12), respectively. Moreover, (90)Y-derived water ages in a community water system (6.8 × 10(4) m(3) d(-1) capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  2. Accuracy of egg flotation throughout incubation to determine embryo age and incubation day in water bird nests

    USGS Publications Warehouse

    Ackerman, J.T.; Eagles-Smith, C. A.

    2010-01-01

    Floating bird eggs to estimate their age is a widely used technique, but few studies have examined its accuracy throughout incubation. We assessed egg flotation for estimating hatch date, day of incubation, and the embryo's developmental age in eggs of the American Avocet (Recurvirostra americana), Black-necked Stilt (Himantopus mexicanus), and Forster's Tern (Sterna forsteri). Predicted hatch dates based on egg flotation during our first visit to a nest were highly correlated with actual hatch dates (r = 0.99) and accurate within 2.3 ?? 1.7 (SD) days. Age estimates based on flotation were correlated with both day of incubation (r = 0.96) and the embryo's developmental age (r = 0.86) and accurate within 1.3 ?? 1.6 days and 1.9 ?? 1.6 days, respectively. However, the technique's accuracy varied substantially throughout incubation. Flotation overestimated the embryo's developmental age between 3 and 9 days, underestimated age between 12 and 21 days, and was most accurate between 0 and 3 days and 9 and 12 days. Age estimates based on egg flotation were generally accurate within 3 days until day 15 but later in incubation were biased progressively lower. Egg flotation was inaccurate and overestimated embryo age in abandoned nests (mean error: 7.5 ?? 6.0 days). The embryo's developmental age and day of incubation were highly correlated (r = 0.94), differed by 2.1 ?? 1.6 days, and resulted in similar assessments of the egg-flotation technique. Floating every egg in the clutch and refloating eggs at subsequent visits to a nest can refine age estimates. ?? The Cooper Ornithological Society 2010.

  3. An evaluation of the precision of fin ray, otolith, and scale age determinations for brook trout

    USGS Publications Warehouse

    Stolarski, J.T.; Hartman, K.J.

    2008-01-01

    The ages of brook trout Salvelinus fontinalis are typically estimated using scales despite a lack of research documenting the effectiveness of this technique. The use of scales is often preferred because it is nonlethal and is believed to require less effort than alternative methods. To evaluate the relative effectiveness of different age estimation methodologies for brook trout, we measured the precision and processing times of scale, sagittal otolith, and pectoral fin ray age estimation techniques. Three independent readers, age bias plots, coefficients of variation (CV = 100 x SD/mean), and percent agreement (PA) were used to measure within-reader, among-structure bias and within-structure, among-reader precision. Bias was generally minimal; however, the age estimates derived from scales tended to be lower than those derived from otoliths within older (age > 2) cohorts. Otolith, fin ray, and scale age estimates were within 1 year of each other for 95% of the comparisons. The measures of precision for scales (CV = 6.59; PA = 82.30) and otoliths (CV = 7.45; PA = 81.48) suggest higher agreement between these structures than with fin rays (CV = 11.30; PA = 65.84). The mean per-sample processing times were lower for scale (13.88 min) and otolith techniques (12.23 min) than for fin ray techniques (22.68 min). The comparable processing times of scales and otoliths contradict popular belief and are probably a result of the high proportion of regenerated scales within samples and the ability to infer age from whole (as opposed to sectioned) otoliths. This research suggests that while scales produce age estimates rivaling those of otoliths for younger (age > 3) cohorts, they may be biased within older cohorts and therefore should be used with caution. ?? Copyright by the American Fisheries Society 2008.

  4. A Model-based Prognostics Methodology for Electrolytic Capacitors Based on Electrical Overstress Accelerated Aging

    NASA Technical Reports Server (NTRS)

    Celaya, Jose; Kulkarni, Chetan; Biswas, Gautam; Saha, Sankalita; Goebel, Kai

    2011-01-01

    A remaining useful life prediction methodology for electrolytic capacitors is presented. This methodology is based on the Kalman filter framework and an empirical degradation model. Electrolytic capacitors are used in several applications ranging from power supplies on critical avionics equipment to power drivers for electro-mechanical actuators. These devices are known for their comparatively low reliability and given their criticality in electronics subsystems they are a good candidate for component level prognostics and health management. Prognostics provides a way to assess remaining useful life of a capacitor based on its current state of health and its anticipated future usage and operational conditions. We present here also, experimental results of an accelerated aging test under electrical stresses. The data obtained in this test form the basis for a remaining life prediction algorithm where a model of the degradation process is suggested. This preliminary remaining life prediction algorithm serves as a demonstration of how prognostics methodologies could be used for electrolytic capacitors. In addition, the use degradation progression data from accelerated aging, provides an avenue for validation of applications of the Kalman filter based prognostics methods typically used for remaining useful life predictions in other applications.

  5. Prevalence of ultrasound-determined cystic endometrial hyperplasia and the relationship with age in dogs.

    PubMed

    Moxon, Rachel; Whiteside, Helen; England, Gary C W

    2016-09-01

    To investigate the potential relationship between age and diagnosis of cystic endometrial hyperplasia (CEH) in the bitches, 348 ultrasound examinations from 240 bitches (Labradors, Golden Retrievers, German Shepherds, Flat Coated Retrievers, or crosses of those breeds aged between 1.6 and 7.2 years at examination) were examined. A subpopulation of 32 bitches that had completed their breeding careers at 6 years or more of age was also identified. Of all, 18.3% of the bitches were diagnosed with CEH; these cases were newly diagnosed when bitches were between 2.5 years and 7.3 years of age. The proportion of ultrasound examinations in which CEH was identified increased from 6.8% of examinations on 2-year-old breeding bitches to 60.0% of examinations on 6-year-old bitches. Logistic regression identified a positive correlation between mean age at the examination and presence of CEH (χ(2) = 30.74, degrees of freedom = 1, P < 0.001). For 32 bitches that had completed their breeding career, the prevalence of CEH was 56.3%, age at the diagnosis ranged from 3.8 to 7.3 years, and the proportion of bitches affected with CEH increased from 6.3% at 3 years of age to 56.3% at 7 years of age. These data support the contention that the prevalence of CEH increases with age.

  6. Determination of the age distribution of sea ice from Lagrangian observations of ice motion

    SciTech Connect

    Kwok, R.; Cunningham, G.F.; Rothrock, D.A.; Stern, H.L.

    1995-03-01

    A procedure for monitoring the local age distribution of the Arctic sea ice cover is presented. The age distribution specifies the area covered by ice in different age classes. In the authors` approach, a regular array of grid points is defined initially on the first image of a long time series, and an ice tracker finds the positions of those points in all subsequent images of the series. These Lagrangian points mark the corners of a set of cells that move and deform with the ice cover. The area of each cell changes with each new image or time step. A positive change indicates that ice in a new age class was formed in the cell. A negative change is assumed to have ridged the youngest ice in the cell, reducing its area. The ice in each cell ages as it progresses through the time series. The area of multiyear ice in each cell is computed using an ice classification algorithm. Any area that is not accounted for by the young ice or multiyear ice is assigned to a category of older first-year ice. They thus have a fine age resolution in the young end of the age distribution, and coarse resolution for older ice. The age distribution of the young ice can be converted to a thickness distribution using a simple empirical relation between accumulated freezing-degree days and ice thickness, or using a more complicated thermodynamic model. They describe a general scheme for implementing this procedure for the Arctic Ocean from fall freeze-up until the onset of melt in the spring. The concept is illustrated with a time series of five ERS-1 SAR images spanning a period of 12 days. Such a scheme could be implemented with RADARSAT SAR imagery to provide basin-wide ice age and thickness information.

  7. Epigenetic age predictions based on buccal swabs are more precise in combination with cell type-specific DNA methylation signatures

    PubMed Central

    Eipel, Monika; Mayer, Felix; Arent, Tanja; Ferreira, Marcelo R. P.; Birkhofer, Carina; Gerstenmaier, Uwe; Costa, Ivan G.; Ritz-Timme, Stefanie; Wagner, Wolfgang

    2016-01-01

    Aging is reflected by highly reproducible DNA methylation (DNAm) changes that open new perspectives for estimation of chronological age in legal medicine. DNA can be harvested non-invasively from cells at the inside of a person's cheek using buccal swabs – but these specimens resemble heterogeneous mixtures of buccal epithelial cells and leukocytes with different epigenetic makeup. In this study, we have trained an age predictor based on three age-associated CpG sites (associated with the genes PDE4C, ASPA, and ITGA2B) for swab samples to reach a mean absolute deviation (MAD) between predicted and chronological age of 4.3 years in a training set and of 7.03 years in a validation set. Subsequently, the composition of buccal epithelial cells versus leukocytes was estimated by two additional CpGs (associated with the genes CD6 and SERPINB5). Results of this “Buccal-Cell-Signature” correlated with cell counts in cytological stains (R2 = 0.94). Combination of cell type-specific and age-associated CpGs into one multivariate model enabled age predictions with MADs of 5.09 years and 5.12 years in two independent validation sets. Our results demonstrate that the cellular composition in buccal swab samples can be determined by DNAm at two cell type-specific CpGs to improve epigenetic age predictions. PMID:27249102

  8. A phylogenetically based transcriptome age index mirrors ontogenetic divergence patterns.

    PubMed

    Domazet-Lošo, Tomislav; Tautz, Diethard

    2010-12-01

    Parallels between phylogeny and ontogeny have been discussed for almost two centuries, and a number of theories have been proposed to explain such patterns. Especially elusive is the phylotypic stage, a phase during development where species within a phylum are particularly similar to each other. Although this has formerly been interpreted as a recapitulation of phylogeny, it is now thought to reflect an ontogenetic progression phase, where strong constraints on developmental regulation and gene interactions exist. Several studies have shown that genes expressed during this stage evolve at a slower rate, but it has so far not been possible to derive an unequivocal molecular signature associated with this stage. Here we use a combination of phylostratigraphy and stage-specific gene expression data to generate a cumulative index that reflects the evolutionary age of the transcriptome at given ontogenetic stages. Using zebrafish ontogeny and adult development as a model, we find that the phylotypic stage does indeed express the oldest transcriptome set and that younger sets are expressed during early and late development, thus faithfully mirroring the hourglass model of morphological divergence. Reproductively active animals show the youngest transcriptome, with major differences between males and females. Notably, ageing animals express increasingly older genes. Comparisons with similar data sets from flies and nematodes show that this pattern occurs across phyla. Our results indicate that an old transcriptome marks the phylotypic phase and that phylogenetic differences at other ontogenetic stages correlate with the expression of newly evolved genes. PMID:21150997

  9. Accelerated thermal aging of petroleum-based ferrofluids

    NASA Astrophysics Data System (ADS)

    Segal, V.; Nattrass, D.; Raj, K.; Leonard, D.

    1999-07-01

    The effect of elevated temperature on the physical and insulating properties of ferrofluid specifically developed for use as a liquid dielectric (D-fluid) for power transformers has been investigated. The D-fluid was produced as a colloidal mix of a specifically synthesized ferrofluid with a conventional mineral oil, and it was subjected to thermal aging conditions modeled after a typical power transformer where the insulation fluid is expected to retain its dielectric performance for about 40 years of continuous service in a sealed tank. The well-known Arrhenius relationship was employed to model "life in service" for up to 40 years at 105°C which corresponded to holding the samples in sealed jars for 10 weeks at 185°C. Another set of small ampules (5 ml) was prepared to test the main physical properties after even longer aging. D-fluid tested after a period of 34 and 50 weeks at 185°C showed no degradation of thermal or colloid stability. The dielectric colloid was also subjected to a 21 day-long test at 110°C in a sealed jar in the presence of typical transformer materials: copper, cellulose, and silicon steel (so-called "bomb" test). Finally, the ferrofluid went through an oxidation stability test (ASTM D2440). Test results show that the newly developed dielectric colloid satisfies the long-term service requirements the transformer users typically apply to conventional mineral oils.

  10. Determination of threshold and maximum operating electric stresses for selected high voltage insulations: Investigation of aged polymeric dielectric cable. Final report

    SciTech Connect

    Eager, G.S. Jr.; Seman, G.W.; Fryszczyn, B.

    1995-11-01

    Based on the successful completion of the extensive research project DOE/ET/29303-1 February 1982 to develop a new method for the determination of threshold voltage in XLPE and EPR insulated cables, tests were initiated to establish the maximum safe operating voltage stresses of crosslinked polyethylene insulated cables that become wet when they operate in a moist environment. The present report covers the measurement of the threshold voltage, the a.c. breakdown voltage and the impulse breakdown voltage of XLPE cable after undergoing accelerated laboratory aging in water. Model and 15 kV XLPE cables were manufactured in commercial equipment using state-of-the-art semiconducting shields and XLPE insulation. The threshold voltage, a.c. voltage breakdown and impulse voltage breakdown of the model cables were determined before aging, after aging one week and after aging 26 weeks. The model cable, following 26 weeks aging, was dried by passing dry gas through the conductor interstices which removed moisture from the cable. The threshold voltage, the a.c. voltage breakdown and the impulse voltage breakdown of the XLPE model cable after drying was measured.

  11. BANYAN. IV. Fundamental parameters of low-mass star candidates in nearby young stellar kinematic groups—isochronal age determination using magnetic evolutionary models

    SciTech Connect

    Malo, Lison; Doyon, René; Albert, Loïc; Lafrenière, David; Artigau, Étienne; Gagné, Jonathan; Feiden, Gregory A.; Riedel, Adric E-mail: doyon@astro.umontreal.ca

    2014-09-01

    Based on high-resolution optical spectra obtained with ESPaDOnS at Canada-France-Hawaii Telescope, we determine fundamental parameters (T {sub eff}, R, L {sub bol}, log g, and metallicity) for 59 candidate members of nearby young kinematic groups. The candidates were identified through the BANYAN Bayesian inference method of Malo et al., which takes into account the position, proper motion, magnitude, color, radial velocity, and parallax (when available) to establish a membership probability. The derived parameters are compared to Dartmouth magnetic evolutionary models and field stars with the goal of constraining the age of our candidates. We find that, in general, low-mass stars in our sample are more luminous and have inflated radii compared to older stars, a trend expected for pre-main-sequence stars. The Dartmouth magnetic evolutionary models show a good fit to observations of field K and M stars, assuming a magnetic field strength of a few kG, as typically observed for cool stars. Using the low-mass members of the β Pictoris moving group, we have re-examined the age inconsistency problem between lithium depletion age and isochronal age (Hertzspring-Russell diagram). We find that the inclusion of the magnetic field in evolutionary models increases the isochronal age estimates for the K5V-M5V stars. Using these models and field strengths, we derive an average isochronal age between 15 and 28 Myr and we confirm a clear lithium depletion boundary from which an age of 26 ± 3 Myr is derived, consistent with previous age estimates based on this method.

  12. First molar eruption in cattle and its use in age determination.

    PubMed

    Andrews, A H

    1980-11-01

    Two studies were undertaken into the intraoral eruption of the first molar in live cattle. The first was a longitudinal survey using monthly observations of Welsh Black bulls and the second involved 300 animals of both sexes and varying breeds, reared under different management systems, using the cross-sectional technique. There were significant differences between the ages at most successive molar codes in both studies. However, a comparison between the two studies showed the mean age at each stage of molar development was higher in the longitudinal study and at three stages this was significant. The age range for each molar code, obtained from the two studies combined, varied between 2.0 and 4.7 months but indicated that the eruption of the first molar tooth was of use in age assessment.

  13. Sensitivity of proton NMR relaxation times in a HTPB based polyurethane elastomer to thermo-oxidative aging.

    SciTech Connect

    Assink, Roger Alan; Mowery, Daniel Michael; Celina, Mathias Christopher

    2004-09-01

    Solid-state {sup 1}H NMR relaxometry studies were conducted on a hydroxy-terminated polybutadiene (HTPB) based polyurethane elastomer thermo-oxidatively aged at 80 C. The {sup 1}H T{sub 1}, T{sub 2}, and T{sub 1{rho}} relaxation times of samples thermally aged for various periods of time were determined as a function of NMR measurement temperature. The response of each measurement was calculated from a best-fit linear function of the relaxation time vs. aging time. It was found that the T{sub 2,H} and T{sub 1{rho},H} relaxation times exhibited the largest response to thermal degradation, whereas T{sub 1,H} showed minimal change. All of the NMR relaxation measurements on solid samples showed significantly less sensitivity to thermal aging than the T{sub 2,H} relaxation times of solvent-swollen samples.

  14. 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.

  15. Using naturally occurring radionuclides to determine drinking water age in a community water system

    SciTech Connect

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  16. Holocene age of the Yuha burial: Direct radiocarbon determinations by accelerator mass spectrometry

    USGS Publications Warehouse

    Stafford, Thomas W.; Jull, A.J.T.; Zabel, T.H.; Donahue, D.J.; Duhamel, R.C.; Brendel, K.; Haynes, C.V.; Bischoff, J.L.; Payen, L.A.; Taylor, R.E.

    1984-01-01

    The view that human populations may not have arrived in the Western Hemisphere before about 12,000 radiocarbon yr BP1,2 has been challenged by claims of much greater antiquity for a small number of archaeological sites and human skeleton samples. One such site is the Homo sapiens sapiens cairn burial excavated in 1971 from the Yuha desert, Imperial County, California3-5. Radiocarbon analysis of caliche coating one of the bones of the skeleton yielded a radiocarbon age of 21,500??1,000 yr BP4, while radiocarbon and uranium series analyses of caliche coating a cairn boulder yielded ages of 22,125??400 and 19,000??3,000 yr BP, respectively5. The late Pleistocene age assignment to the Yuha burial has been challenged by comparing the cultural context of the burial with other cairn burials in the same region6, on the basis of the site's geomorphological context and from radiocarbon analyses of soil caliches. 7,8 In rebuttal, arguments in defence of the original age assignment have been presented9,10 as well as an amino acid racemization analysis on the Yuha skeleton indicating an age of 23,600??2,600 yr BP11. The tandem accelerator mass spectrometer at the University of Arizona has now been used to measure the ratio of 14C/13C in several organic and inorganic fractions of post-cranial bone from the Yuha H. sapiens sapiens skeleton. Isotope ratios from six chemical fractions all yielded radiocarbon ages for the skeleton of less than 4,000 yr BP. These results indicate that the Yuha skeleton is of Holocene age, in agreement with the cultural context of the burial, and in disagreement with the previously assigned Pleistocene age of 19,000-23,000 yr. ?? 1984 Nature Publishing Group.

  17. Determination of the age of hydrothermal fluids by the kinetic-geochemical method

    SciTech Connect

    Reznikov, A.N.

    1995-03-01

    An estimate of the age of hydrothermal fluids at rift zones of oceans and continents, island arc regions, as well as regions of mud volcanism and occurrences of condensation and solution waters of hydrocarbon accumulations is given on the basis of the chemical, gas, and isotopic compositions and geothermobaric conditions. Correlations between the degree of accumulation of trace elements in hydrothermal fluids and their age were established.

  18. A MASSIF Effort To Determine The Mass-Luminosity Relation for Stars of Various Ages, Metallicities, and Evolution States

    NASA Technical Reports Server (NTRS)

    Henry, Todd J.; Beedict, G. Fritz; Gies, Douglas R.; Golimowski, David A.; Ianna, Philip A.; Mason, Brian; McArthur, Barbara; Nelan, Edmund; Torres, Guillermo

    2004-01-01

    The MASSIF (Masses and Stellar Systems with Interferometry) Team will use SIM to investigate the mass content of the Galaxy - from huge stars to barely glimmering brown dwarfs, and from hot white dwarfs to exotic black holes. We will target various samples of the Galactic population to determine and relate the fundamental characteristics of mass, luminosity, age, composition, and multiplicity - attributes that together yield an extensive understanding of the stars. Our samples will include distant clusters that span a factor of 5000 in age, and commonplace stars and substellar objects that lurk near the Sun. The principal goals of the MASSIF Key Project are to (1) define the mass-luminosity relation for main sequence stars in five fundamental clusters so that effects of age and metallicity can be mapped (Trapezium, TW Hydrae, Pleiades, Hyades, and M67), and (2) determine accurate masses for representative examples of nearly every type of star, stellar descendant or brown dwarf in the Galaxy.

  19. 69 FR 8512 - Culturally Significant Objects Imported for Exhibition; Determinations: “Coming of Age in Ancient...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2004-02-24

    ....), Delegation of Authority No. 234 of October 1, 1999 (64 FR 56014), Delegation of Authority No. 236 of October 19, 1999 (64 FR 57920), as amended, and Delegation of Authority No. 257 of April 15, 2003 (68 FR... Culturally Significant Objects Imported for Exhibition; Determinations: ``Coming of Age in Ancient...

  20. Determinants of Quality of Life in Ageing Populations: Results from a Cross-Sectional Study in Finland, Poland and Spain

    PubMed Central

    Corso, Barbara; Minicuci, Nadia; Quintas, Rui; Sattin, Davide; De Torres, Laura; Chatterji, Somnath; Frisoni, Giovanni Battista; Haro, Josep Maria; Koskinen, Seppo; Martinuzzi, Andrea; Miret, Marta; Tobiasz-Adamczyk, Beata; Leonardi, Matilde

    2016-01-01

    Purpose To comprehensively identify the determinants of quality of life (QoL) in a population study sample of persons aged 18–50 and 50+. Methods In this observational, cross-sectional study, QoL was measured with the WHOQOL-AGE, a brief instrument designed to measure QoL in older adults. Eight hierarchical regression models were performed to identify determinants of QoL. Variables were entered in the following order: Sociodemographic; Health Habits; Chronic Conditions; Health State description; Vision and Hearing; Social Networks; Built Environment. In the final model, significant variables were retained. The final model was re-run using data from the three countries separately. Results Complete data were available for 5639 participants, mean age 46.3 (SD 18.4). The final model accounted for 45% of QoL variation and the most relevant contribution was given by sociodemographic data (particularly age, education level and living in Finland: 17.9% explained QoL variation), chronic conditions (particularly depression: 4.6%) and a wide and rich social network (4.6%). Other determinants were presence of disabling pain, learning difficulties and visual problems, and living in usable house that is perceived as non-risky. Some variables were specifically associated to QoL in single countries: age in Poland, alcohol consumption in Spain, angina in Finland, depression in Spain, and self-reported sadness both in Finland and Poland, but not in Spain. Other were commonly associated to QoL: smoking status, bodily aches, being emotionally affected by health problems, good social network and home characteristics. Conclusions Our results highlight the importance of modifiable determinants of QoL, and provide public health indications that could support concrete actions at country level. In particular, smoking cessation, increasing the level of physical activity, improving social network ties and applying universal design approach to houses and environmental infrastructures could

  1. The GPS based precision orbit determination experiment on TOPEX

    NASA Technical Reports Server (NTRS)

    Melbourne, William G.; Davis, Edgar S.; Yunck, Thomas P.

    1988-01-01

    The objectives of the GPS-based precision orbit determination (POD) experiment on TOPEX are discussed. Problems facing this experiment include the careful design of all network receivers to control uncalibrated systematic group-delay biases and delay variations between channels, and the careful design of both the GPS-antenna-TOPEX satellite interface and the ground antennas to mimimize multipath. Questions of reference frames, geoid recovery, and the application of innovative orbit determination strategies must also be addressed.

  2. Translating CFC-based piston ages into probability density functions of ground-water age in karst

    USGS Publications Warehouse

    Long, A.J.; Putnam, L.D.

    2006-01-01

    Temporal age distributions are equivalent to probability density functions (PDFs) of transit time. The type and shape of a PDF provides important information related to ground-water mixing at the well or spring and the complex nature of flow networks in karst aquifers. Chlorofluorocarbon (CFC) concentrations measured for samples from 12 locations in the karstic Madison aquifer were used to evaluate the suitability of various PDF types for this aquifer. Parameters of PDFs could not be estimated within acceptable confidence intervals for any of the individual sites. Therefore, metrics derived from CFC-based apparent ages were used to evaluate results of PDF modeling in a more general approach. The ranges of these metrics were established as criteria against which families of PDFs could be evaluated for their applicability to different parts of the aquifer. Seven PDF types, including five unimodal and two bimodal models, were evaluated. Model results indicate that unimodal models may be applicable to areas close to conduits that have younger piston (i.e., apparent) ages and that bimodal models probably are applicable to areas farther from conduits that have older piston ages. The two components of a bimodal PDF are interpreted as representing conduit and diffuse flow, and transit times of as much as two decades may separate these PDF components. Areas near conduits may be dominated by conduit flow, whereas areas farther from conduits having bimodal distributions probably have good hydraulic connection to both diffuse and conduit flow. ?? 2006 Elsevier B.V. All rights reserved.

  3. Spatially adapted augmentation of age-specific atlas-based segmentation using patch-based priors

    NASA Astrophysics Data System (ADS)

    Liu, Mengyuan; Seshamani, Sharmishtaa; Harrylock, Lisa; Kitsch, Averi; Miller, Steven; Chau, Van; Poskitt, Kenneth; Rousseau, Francois; Studholme, Colin

    2014-03-01

    One of the most common approaches to MRI brain tissue segmentation is to employ an atlas prior to initialize an Expectation- Maximization (EM) image labeling scheme using a statistical model of MRI intensities. This prior is commonly derived from a set of manually segmented training data from the population of interest. However, in cases where subject anatomy varies significantly from the prior anatomical average model (for example in the case where extreme developmental abnormalities or brain injuries occur), the prior tissue map does not provide adequate information about the observed MRI intensities to ensure the EM algorithm converges to an anatomically accurate labeling of the MRI. In this paper, we present a novel approach for automatic segmentation of such cases. This approach augments the atlas-based EM segmentation by exploring methods to build a hybrid tissue segmentation scheme that seeks to learn where an atlas prior fails (due to inadequate representation of anatomical variation in the statistical atlas) and utilize an alternative prior derived from a patch driven search of the atlas data. We describe a framework for incorporating this patch-based augmentation of EM (PBAEM) into a 4D age-specific atlas-based segmentation of developing brain anatomy. The proposed approach was evaluated on a set of MRI brain scans of premature neonates with ages ranging from 27.29 to 46.43 gestational weeks (GWs). Results indicated superior performance compared to the conventional atlas-based segmentation method, providing improved segmentation accuracy for gray matter, white matter, ventricles and sulcal CSF regions.

  4. Ochoan (upper Permian) stratigraphy and age determinations, southeastern New Mexico and west Texas

    SciTech Connect

    Lucas, S.G. ); Anderson, O.R. )

    1994-03-01

    Upper Permian strata, which are the stratotype of the Ochoan State (Series), have an extensive subsurface distribution and limited outcrop area in southeastern New Mexico and west Texas. The oldest strata are alternating laminae of anhydrite and calcite of the Castile Formation and are as much as 700 m thick. The closely related and overlying Salado Formation is a much as 600 m thick and is mostly halite and argillaceous halite with minor anhydrite. The overlying Rustler Formation is as much as 150 m thick and consists of anhydrite, red silty shale and magnesian limestone. Overlying red beds are the Quartermaster Formation (Dewey Lake Formation is a synonym, as is the term Pierce Canyon red beds), which is as much as 106 m thick and consist of fine sandstones, siltstones, and minor gypsum. The Castile rests disconformably on the Capitanian (middle Permian) Lamar Limestone Member of the Bell Canyon Formation and its equivalent, the Tansill Formation of the Artesia Group. Counting of Castile-Salado laminae and their posited relationship to astronomical cycles suggests that Castile-Salado deposition took only 200,000-300,000 yr. Limited assemblages of brachiopods and conodonts from the Rustler Formation indicate a Late Permian age, but are no more precise age indicators. A small assemblage of bivalves, K-Ar ages and magnetostratigraphy indicate a late Permian age for the Quartermaster Formation. There is no evidence to support a Triassic age assignment for the Quarter-master; it is disconformably overlain by the Upper Triassic (Carnian) Chinle group. Most workers us the Ochoan as a Late Permian Stage-Age, although its typical strata generally lack good age indicators and may represent relatively short and sporadic intervals of the Late Permian. We prefer recognition of the Ochoan as a lithostratigraphic unit (group) without regional or global geochronologial significance.

  5. Anthropometric, bone age, and bone mineral density changes after a family-based treatment for obese children.

    PubMed

    Bermudez de la Vega, J Antonio; Vázquez, M Angeles; Bernal, Susana; Gentil, F Javier; Gonzalez-Hachero, Jose; Montoya, M Jose; Pérez-Cano, Ramón

    2007-10-01

    Our objective was to identify anthropometric, bone age, and bone mineral density (BMD) changes after a family-based treatment program for obese children. We conducted a longitudinal prospective study of 50 obese children (body mass index percentage [BMI%] > or =120%) aged 9.12 +/- 1.72 years (range 6-13) at baseline. A family-based treatment program, based on inadequate feeding style with progressive modification, aerobic physical exercise increase, active parental involvement, and the use of behavioural strategies (contracting, self-monitoring, social reinforcement), was developed during a 12-month period. Anthropometric data, lumbar spine (L2-L4) BMD by dual-energy X-ray absorptiometry, bone age (BA), bone age to chronological age ratio (BA/CA), and predicted adult height (PAH) were determined at baseline and 12 months. The statistical method used was analysis of variance and the paired Student t-test. Mean BMI standard deviation score (SDS) loss was -0.61 +/- 0.76 and BMI% loss was -5.17 +/- 9.73%. Height SDS significantly decreased, BA/CA ratio also decreased significantly, and PAH change was not significant. Lumbar spine BMD SDS and BMD% did not significantly change. A family-based treatment program was effective in obese children by reducing by 5% the BMI in 1 year and increasing the activity level. Treatment reduced growth velocity and delayed bone maturation rate without affecting PAH, reflecting a situation of previous early maturation. The treatment did not modify gaining bone mass.

  6. Ar-40/Ar-39 age determinations for the Rotoiti eruption, New Zealand

    NASA Astrophysics Data System (ADS)

    Flude, S.; Storey, M.

    2013-12-01

    The contemporaneous Rotoiti and Earthquake Flat ignimbrites, erupted from the Taupo Volcanic zone, New Zealand, form a distinctive tephrostratigraphic horizon in the Southern Pacific. Radioisotopic dating results for these eruptions remain controversial, with published ages ranging from 35.1 × 2.8 ka [1] to 71 × 6 ka [2], with 61.0 × 1.5 ka [3] often being cited as the most widely accepted age. These eruptions are difficult to date as their age is near the limit for various radiometric dating techniques, which are complicated by a large proportion of inherited material (xenocrysts) and a lack of phases suitable for dating. Glass-bearing plutonic blocks erupted with the Rotoiti and Earthquake Flat ignimbrites have previously been interpreted as deriving from a slowly cooled and incompletely solidified magma body that was sampled by the eruptions. They contain large vugs lined with euhedral quartz, sanidine and biotite crystals, indicating that these crystals grew in a gas or aqueous fluid rich environment and are interpreted to have formed shortly before or during eruption. Here we will present Ar-40/Ar-39 ages for sanidines and biotites extracted from vugs in lithic blocks erupted as part of the Earthquake Flat ignimbrite. We show that, even for vug-lining material, inherited ages remain a problem and are the likely source of the wide variation in published radiometric ages. Nevertheless, many of the Ar-40/Ar-39 ages are much younger than the 61 ka age [3] and are more consistent with the recent stratigraphic, C-14 and U-238/Th-230+(U-Th)/He ages that have been suggested (e.g. [4,5]). 1. Whitehead, N. & Ditchburn, R. New Zealand Journal of Geology and Geophysics 37, 381-383 (1994). 2. Ota, Y., Omura, A. & Iwata, H. New Zealand Journal of Geology and Geophysics 32, 327-331 (1989). 3. Wilson, C. J. N. et al. Quaternary Science Reviews 26, 1861-1870 (2007). 4. Molloy, C., Shane, P. & Augustinus, P. Geological Society of America Bulletin 121, 1666-1677 (2009). 5

  7. An agent-based computational model for tuberculosis spreading on age-structured populations

    NASA Astrophysics Data System (ADS)

    Graciani Rodrigues, C. C.; Espíndola, Aquino L.; Penna, T. J. P.

    2015-06-01

    In this work we present an agent-based computational model to study the spreading of the tuberculosis (TB) disease on age-structured populations. The model proposed is a merge of two previous models: an agent-based computational model for the spreading of tuberculosis and a bit-string model for biological aging. The combination of TB with the population aging, reproduces the coexistence of health states, as seen in real populations. In addition, the universal exponential behavior of mortalities curves is still preserved. Finally, the population distribution as function of age shows the prevalence of TB mostly in elders, for high efficacy treatments.

  8. Determination of Reddening and Age for Ten Large Magellanic Cloud Star Clusters from Integrated Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ahumada, Andrea V.; Vega, Luis R.; Clariá, Juan J.; Oddone, Mónica A.; Palma, Tali

    2016-09-01

    We present flux-calibrated integrated spectra in the optical range (3700-6800 Å) obtained at Complejo Astronómico El Leoncito (CASLEO, Argentina) for a sample of 10 concentrated star clusters belonging to the Large Magellanic Cloud (LMC). No previous data exist for two of these objects (SL 142 and SL 624), while most of the remaining clusters have been only poorly studied. We derive simultaneously foreground E(B - V) reddening values and ages for the cluster sample by comparing their integrated spectra with template LMC cluster spectra and with two different sets of simple stellar population models. Cluster reddening values and ages are also derived from both available interstellar extinction maps and by using diagnostic diagrams involving the sum of equivalent widths of some selected spectral features and their calibrations with age, respectively. For the studied sample, we derive ages between 1 Myr and 240 Myr. In an effort to create a spectral library at the LMC metallicity level with several clusters per age range, the cluster sample presented here stands out as a useful complement to previous ones.

  9. Beta2-Adrenergic Receptor Gene Polymorphisms as Systemic Determinants of Healthy Aging in an Evolutionary Context

    PubMed Central

    Kulminski, Alexander M.; Culminskaya, Irina V.; Ukraintseva, Svetlana V.; Arbeev, Konstantin G.; Land, Kenneth C.; Yashin, Anatoli I.

    2010-01-01

    The Gln27Glu polymorphism but not the Arg16Gly polymorphism of the beta2-adrenergic receptor (ADRB2) gene appears to be associated with a broad range of aging-associated phenotypes, including cancers at different sites, myocardial infarction (MI), intermittent claudication (IC), and overall/healthy longevity in the Framingham Heart Study Offspring cohort. The Gln27Gln genotype increases risks of cancer, MI and IC, whereas the Glu27 allele or, equivalently, the Gly16Glu27 haplotype tends to be protective against these diseases. Genetic associations with longevity are of opposite nature at young-old and oldest-old ages highlighting the phenomenon of antagonistic pleiotropy. The mechanism of antagonistic pleiotropy is associated with an evolutionary-driven advantage of carriers of a derived Gln27 allele at younger ages and their survival disadvantage at older ages as a result of increased risks of cancer, MI and IC. The ADRB2 gene can play an important systemic role in healthy aging in evolutionary context that warrants exploration in other populations. PMID:20399803

  10. A Model to Determine the Likely Age of an Adolescent’s First Drink of Alcohol

    PubMed Central

    Chan, Grace; Kramer, John R.; Wetherill, Leah; Bucholz, Kathleen K.; Dick, Danielle; Hesselbrock, Victor; Porjesz, Bernice; Rangaswamy, Madhavi; Schuckit, Marc

    2013-01-01

    OBJECTIVE: With the use of a new cohort of adolescent subjects, predictors from the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) interview and the Achenbach Youth Self Report (YSR) were combined to model age of first drink (AFD). METHODS: Subjects consisted of 820 adolescents (ages 14–17) drawn from the current phase of the Collaborative Study on the Genetics of Alcoholism. Three Cox proportional hazards models were considered. Model 1 contained SSAGA variables equivalent to AFD predictors from our previous study: interview age, family history of alcohol dependence, and number of conduct disorder symptoms. Model 2 incorporated 2 additional SSAGA questions (best friends drink and smoked a cigarette before a reported AFD) plus 8 YSR-derived scale scores. Model 3 was a reduced version of model 2, retaining only significant predictors. RESULTS: Model 2 was a significant improvement over model 1. Model 3 was the best and the most parsimonious of the 3 with respect to likelihood ratio and Wald χ2 tests and retained only 5 variables from model 2. Included variables were the following: (1) best friends drink, (2) membership in a high-risk alcohol dependence family, (3) number of conduct disorder symptoms, (4) YSR externalizing score, and (5) YSR social problems score. CONCLUSIONS: Adding variables to those from our original study improved our ability to model the likely age of alcohol initiation. In addition to the SSAGA, the YSR appears to have utility as a research tool to predict the age of alcohol initiation. PMID:23296431

  11. Influence of age and sex on lumbar vertebral morphometry determined using sagittal magnetic resonance imaging.

    PubMed

    Sevinc, Ozdemir; Barut, Cagatay; Is, Merih; Eryoruk, Nesrin; Safak, Alp Alper

    2008-01-01

    We evaluated age-related changes in the morphometric features of lumbar vertebrae in both sexes using magnetic resonance imaging (MRI). Midsagittal MRI scans of 366 individuals (156 males, 210 females; 25-82 years old) were evaluated retrospectively. The anterior height (H(a)), central height (H(c)), posterior height (H(p)), and anteroposterior diameter (D) of the body of each lumbar vertebra were measured. These measurements were used to calculate three indices, namely, the anterior wedge index (H(a)/H(p)), the biconcavity index (H(c)/H(p)), and the compression index (H(p)/D). The values of each of the three indices for the upper lumbar vertebrae of females were higher than those of the same vertebrae in males. The values of the compression index for all lumbar vertebrae decreased with age in females, whereas in males the compression index of the L1-L4 vertebrae decreased with age. No significant changes were observed in the value of the anterior wedge index in either sex. The biconcavity indices of the L1 and L5 vertebrae decreased with age in males. These results may be useful for evaluating age-related morphological changes that occur in the lumbar vertebrae.

  12. Determination of Reddening and Age for Ten Large Magellanic Cloud Star Clusters from Integrated Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ahumada, Andrea V.; Vega, Luis R.; Clariá, Juan J.; Oddone, Mónica A.; Palma, Tali

    2016-09-01

    We present flux-calibrated integrated spectra in the optical range (3700–6800 Å) obtained at Complejo Astronómico El Leoncito (CASLEO, Argentina) for a sample of 10 concentrated star clusters belonging to the Large Magellanic Cloud (LMC). No previous data exist for two of these objects (SL 142 and SL 624), while most of the remaining clusters have been only poorly studied. We derive simultaneously foreground E(B ‑ V) reddening values and ages for the cluster sample by comparing their integrated spectra with template LMC cluster spectra and with two different sets of simple stellar population models. Cluster reddening values and ages are also derived from both available interstellar extinction maps and by using diagnostic diagrams involving the sum of equivalent widths of some selected spectral features and their calibrations with age, respectively. For the studied sample, we derive ages between 1 Myr and 240 Myr. In an effort to create a spectral library at the LMC metallicity level with several clusters per age range, the cluster sample presented here stands out as a useful complement to previous ones.

  13. Determinants of musculoskeletal frailty and the risk of falls in old age.

    PubMed

    Runge, M; Hunter, G

    2006-01-01

    Neuromuscular parameters that describe locomotion are indispensable variables for the diagnosis and treatment of frailty, fall risk and osteoporosis. A scientifically-based standardized locomotor assessment should be an essential part of medical examinations in research and clinical practice. There has been no previous consensus regarding which test procedures should be included in a locomotor assessment. The goal of this article is to provide a rationale for the selection of appropriate locomotor tests in a comprehensive locomotor assessment for elderly patients. We propose that a locomotor assessment should comprise the parameters that have been proven predictive for both falls and impending disability. The parameters should be measured in the standard units of physics. Therefore, we propose the following tests for a standardized locomotor assessment: (1) Self-selected gait velocity as the single best measure of general locomotor status and a good predictor of age-related adverse events; (2) Chair rise test (timed 5 chair rises) which measures power on vertical movement and the hip surrounding muscles as the most important neuromuscular risk factor for falls and fall-related fractures; (3) Tandem standing and tandem walking to measure postural capacity (balance) to the side; (4) Timed up and go test as a global screening procedure; (5) Clinical gait analysis with special focus on regularity; and (6) At least on a research level, movement must be measured referring to the terms of physics by mechanography. Mechanography (Leonardo force plate system, Novotec Pforzheim, Germany) records the time course of ground reaction forces, velocity of the vertical movements of the center of mass and power during unrestricted physiological movements. In the mechanogram the eccentric and concentric phases of movements can be differentiated and the storage of energy in the elastic elements of the body can be examined. The kinetics of human movement is explained by mechanograms of

  14. The usefulness of Belgian formulae in third molar-based age assessment of Indians.

    PubMed

    Bhowmik, Biyas; Acharya, Ashith B; Naikmasur, Venkatesh G

    2013-03-10

    The third molars are one of few useful predictors for assessing the degree of maturity in adolescence and young adulthood. It has application in age estimation in the age group of 14-23 years, in general, and in juvenile/adult status prediction, in particular. Using a 10-stage grading of third molars, Gunst et al. developed regression formulae on a large sample of Belgians (n=2513) for estimating age. Their research has been recommended as a 'reference study' in age estimation guidelines. The present study has ventured to determine if estimating age in Indians using the Belgian formulae produced results comparable to those reported in the Belgian study; in addition, this study attempts to determine if the same formulae predicted juvenile/adult status (age aged between 14 and 23 years. The OPGs included a mix of one, two, three and four third molars. In total, 916 teeth were assessed using the same 10-stage grading. Age in each OPG was estimated by applying the relevant Belgian regression formulae (regression formulae are available for one, two, three and four third molars). To determine if the formulae produced age estimates comparable to those in the Belgian study, the percentage of Indian subjects whose actual age fell within the 68% confidence interval (CI) (calculated from the ± 1 S.D. value available for each Belgian formula) was ascertained. If ≥ 68% of Indian subjects' age fell inside this interval, it indicates that the Belgian formulae are applicable in Indians. To assess the suitability of the Belgian formulae in predicting juvenile/adult status in Indians, the accuracy of the age estimation per se was not considered, rather, the number of correct age predictions only was noted. Overall, ≈ 74% of Indian subjects' actual age fell within the 68% CI; with regards to the Belgian formulae being able to correctly predict juvenile/adult status

  15. The usefulness of Belgian formulae in third molar-based age assessment of Indians.

    PubMed

    Bhowmik, Biyas; Acharya, Ashith B; Naikmasur, Venkatesh G

    2013-03-10

    The third molars are one of few useful predictors for assessing the degree of maturity in adolescence and young adulthood. It has application in age estimation in the age group of 14-23 years, in general, and in juvenile/adult status prediction, in particular. Using a 10-stage grading of third molars, Gunst et al. developed regression formulae on a large sample of Belgians (n=2513) for estimating age. Their research has been recommended as a 'reference study' in age estimation guidelines. The present study has ventured to determine if estimating age in Indians using the Belgian formulae produced results comparable to those reported in the Belgian study; in addition, this study attempts to determine if the same formulae predicted juvenile/adult status (age aged between 14 and 23 years. The OPGs included a mix of one, two, three and four third molars. In total, 916 teeth were assessed using the same 10-stage grading. Age in each OPG was estimated by applying the relevant Belgian regression formulae (regression formulae are available for one, two, three and four third molars). To determine if the formulae produced age estimates comparable to those in the Belgian study, the percentage of Indian subjects whose actual age fell within the 68% confidence interval (CI) (calculated from the ± 1 S.D. value available for each Belgian formula) was ascertained. If ≥ 68% of Indian subjects' age fell inside this interval, it indicates that the Belgian formulae are applicable in Indians. To assess the suitability of the Belgian formulae in predicting juvenile/adult status in Indians, the accuracy of the age estimation per se was not considered, rather, the number of correct age predictions only was noted. Overall, ≈ 74% of Indian subjects' actual age fell within the 68% CI; with regards to the Belgian formulae being able to correctly predict juvenile/adult status

  16. Social Determinants, Race, and Brain Health Outcomes: Findings from the Chicago Health and Aging Project.

    PubMed

    Aggarwal, Neelum T; Everson-Rose, Susan A; Evans, Denis A

    2015-01-01

    The broad spectrum of economic and cultural diversity in the U.S. population correlates with and affects the study of behavioral aspects of health. The purpose of this article is to provide a selective overview of research findings from the Chicago Health and Aging Project (CHAP), which covers a socio-demographically diverse population in Chicago, with a focus on role-related psychosocial factors and observed racial/ethnic differences in aging outcomes. CHAP is a longitudinal, epidemiological study of common chronic conditions of aging with an emphasis on medical, psychosocial, and environmental risk factors for the decline in cognitive function across the older adult lifespan. We briefly summarize the study design and methods used in the CHAP study and characterize the study population and describe the psychosocial data, noting black-white associations as they relate to three common brain health outcomes: cognitive function and Alzheimer's Disease, stroke, and subclinical vascular disease as noted on neuroimaging. PMID:26239039

  17. Social Determinants, Race, and Brain Health Outcomes: Findings from the Chicago Health and Aging Project.

    PubMed

    Aggarwal, Neelum T; Everson-Rose, Susan A; Evans, Denis A

    2015-01-01

    The broad spectrum of economic and cultural diversity in the U.S. population correlates with and affects the study of behavioral aspects of health. The purpose of this article is to provide a selective overview of research findings from the Chicago Health and Aging Project (CHAP), which covers a socio-demographically diverse population in Chicago, with a focus on role-related psychosocial factors and observed racial/ethnic differences in aging outcomes. CHAP is a longitudinal, epidemiological study of common chronic conditions of aging with an emphasis on medical, psychosocial, and environmental risk factors for the decline in cognitive function across the older adult lifespan. We briefly summarize the study design and methods used in the CHAP study and characterize the study population and describe the psychosocial data, noting black-white associations as they relate to three common brain health outcomes: cognitive function and Alzheimer's Disease, stroke, and subclinical vascular disease as noted on neuroimaging.

  18. Determining the Age of the Kepler Open Cluster NGC 6819 With a New Triple System and Other Eclipsing Binary Stars

    NASA Astrophysics Data System (ADS)

    Brewer, Lauren N.; Sandquist, Eric L.; Mathieu, Robert D.; Milliman, Katelyn; Geller, Aaron M.; Jeffries, Mark W., Jr.; Orosz, Jerome A.; Brogaard, Karsten; Platais, Imants; Bruntt, Hans; Grundahl, Frank; Stello, Dennis; Frandsen, Søren

    2016-03-01

    As part of our study of the old (˜2.5 Gyr) open cluster NGC 6819 in the Kepler field, we present photometric (Kepler and ground-based BVRCIC) and spectroscopic observations of the detached eclipsing binary WOCS 24009 (Auner 665; KIC 5023948) with a short orbital period of 3.6 days. WOCS 24009 is a triple-lined system, and we verify that the brightest star is physically orbiting the eclipsing binary using radial velocities and eclipse timing variations. The eclipsing binary components have masses MB = 1.090 ± 0.010 M⊙ and MC = 1.075 ± 0.013 M⊙, and radii RB = 1.099 ± 0.006 ± 0.005 R⊙ and RC = 1.069 ± 0.006 ± 0.013 R⊙. The bright non-eclipsing star resides at the cluster turnoff, and ultimately its mass will directly constrain the turnoff mass: our preliminary determination is MA = 1.251 ± 0.057 M⊙. A careful examination of the light curves indicates that the fainter star in the eclipsing binary undergoes a very brief period of total eclipse, which enables us to precisely decompose the light of the three stars and place them in the color-magnitude diagram (CMD). We also present improved analysis of two previously discussed detached eclipsing stars in NGC 6819 (WOCS 40007 and WOCS 23009) en route to a combined determination of the cluster’s distance modulus (m - M)V = 12.38 ± 0.04. Because this paper significantly increases the number of measured stars in the cluster, we can better constrain the age of the CMD to be 2.21 ± 0.10 ± 0.20 Gyr. Additionally, using all measured eclipsing binary star masses and radii, we constrain the age to 2.38 ± 0.05 ± 0.22 Gyr. The quoted uncertainties are estimates of measurement and systematic uncertainties (due to model physics differences and metal content), respectively. This is paper 57 of the WIYN Open Cluster Study (WOCS).

  19. Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils.

    PubMed

    Christiansen, Karen S; Borggaard, Ole K; Holm, Peter E; Vijver, Martina G; Hauschild, Michael Z; Peijnenburg, Willie J G M

    2015-04-01

    Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils spiked with Cu and aged for 2 months at 35 °C. Cu toxicity was expressed as pEC50(Cu(2+)), i.e., the negative logarithm of the EC50(Cu(2+)) activity to plant growth. The determined pEC50(Cu(2+)) was significantly and positively correlated with both the analytically readily available soil pH and concentration of dissolved organic carbon [DOC] which together could explain 87% of the pEC50(Cu(2+)) variation according to the simple equation: pEC50(Cu(2+)) = 0.98 × pH + 345 × [DOC] - 0.27. Other soil characteristics, including the base cation concentrations (Na(+), K(+), Ca(2+), Mg(2+)), the cation exchange capacity at soil pH (ECEC), and at pH 7 (CEC7), soil organic carbon, clay content, and electric conductivity as well as the distribution coefficient (Kd) calculated as the ratio between total soil Cu and water-extractable Cu did not correlate significantly with pEC50(Cu(2+)). Consequently, Cu toxicity, expressed as the negative log of the Cu(2+) activity, to plant growth increases at increasing pH and DOC, which needs to be considered in future management of plant growth on Cu-contaminated soils. The developed regression equation allows identification of soil types in which the phytotoxicity potential of Cu is highest.

  20. Is Social Capital a Determinant of Oral Health among Older Adults? Findings from the English Longitudinal Study of Ageing.

    PubMed

    Rouxel, Patrick; Tsakos, Georgios; Demakakos, Panayotes; Zaninotto, Paola; Chandola, Tarani; Watt, Richard Geddie

    2015-01-01

    There are a number of studies linking social capital to oral health among older adults, although the evidence base mainly relies on cross-sectional study designs. The possibility of reverse causality is seldom discussed, even though oral health problems could potentially lead to lower social participation. Furthermore, few studies clearly distinguish between the effects of different dimensions of social capital on oral health. The objective of the study was to examine the longitudinal associations between individual social capital and oral health among older adults. We analyzed longitudinal data from the 3rd and 5th waves of the English Longitudinal Study of Ageing (ELSA). Structural social capital was operationalized using measures of social participation, and volunteering. Number of close ties and perceived emotional support comprised the functional dimension of social capital. Oral health measures were having no natural teeth (edentate vs. dentate), self-rated oral health and oral health-related quality of life. Time-lag and autoregressive models were used to explore the longitudinal associations between social capital and oral health. We imputed all missing data, using multivariate imputation by chained equations. We found evidence of bi-directional longitudinal associations between self-rated oral health, volunteering and functional social capital. Functional social capital was a strong predictor of change in oral health-related quality of life - the adjusted odds ratio of reporting poor oral health-related quality of life was 1.75 (1.33-2.30) for older adults with low vs. high social support. However in the reverse direction, poor oral health-related quality of life was not associated with changes in social capital. This suggests that oral health may not be a determinant of social capital. In conclusion, social capital may be a determinant of subjective oral health among older adults rather than edentulousness, despite many cross-sectional studies on the

  1. Estimation of age at death based on quantitation of the 4977-bp deletion of human mitochondrial DNA in skeletal muscle.

    PubMed

    Meissner, C; von Wurmb, N; Schimansky, B; Oehmichen, M

    1999-11-01

    The 4977-bp deletion in human mitochondrial DNA (mtDNA) is known to accumulate in various tissues with age. Since this deletion in mtDNA correlates closest with age in muscle tissue, iliopsoas muscle tissue was taken at autopsy from 50 persons aged 24-97 years to determine whether age at death can be estimated based on the amount of the 4977-bp deletion in skeletal muscle. Total DNA (nuclear and mtDNA) was extracted from 100 mg tissue and the 4977-bp deletion quantified using a kinetic polymerase chain reaction (PCR) followed by visualization of the products on silver stained polyacrylamide gels. The amount of the 4977-bp deletion of mtDNA ranged from 0.00049% to 0.14% depending on age, with a correlation coefficient of r = 0.83 (P = 0.0001). In forensic practice this method can aid in the estimation of age at death with a relatively wide confidence interval, thus enabling a discrimination between young and elderly persons in the identification of human remains based solely on skeletal muscle.

  2. Stratigraphy and wiggle-matching-based age-depth model of late Holocene marine sediments in Beppu Bay, southwest Japan

    NASA Astrophysics Data System (ADS)

    Kuwae, Michinobu; Yamamoto, Masanobu; Ikehara, Ken; Irino, Tomohisa; Takemura, Keiji; Sagawa, Takuya; Sakamoto, Tatsuhiko; Ikehara, Minoru; Takeoka, Hidetaka

    2013-06-01

    We analyzed the lithology, magnetic susceptibility, bulk density, and X-ray radiographs of 14 sediment cores (1-9 m long) from Beppu Bay in the western Seto Inland Sea, Japan, to establish the late Holocene stratigraphy in the deepest part of the bay and to develop an age-depth model for the sediments there. The cores contained 18 thick (major event) high-density layers (16 turbidites and two volcanic ash; >1 cm thick), and both lithological observations and density variations in the hemipelagic mud that is dominant in the cores revealed a further 55 thin (minor event) high-density layers (<1 cm thick). Analyses of color properties and opal and sand contents of the hemipelagic mud defined nine lithological units. After stratigraphic correlation of the event layers among cores, we projected 14C dates onto a single composite core. Forty-two AMS 14C dates from bivalve mollusk shells were used to construct a wiggle-matching-based age-depth model for the late Holocene sequence and to determine the local reservoir effect (ΔR). The age-depth model showed a sedimentation rate of 0.23-0.30 cm/yr for a 7.8 m-long composite core and an age of ˜2800 cal yr BP at the base. Wiggle-matching provided ΔR values of 115-155 yr for late Holocene bivalve samples from Beppu Bay, which is consistent with previous estimates reported from coastal areas near the Kuroshio Front. Comparison of wiggle-matching-derived ages of thick turbidites with the ages of historical earthquakes showed differences within ±25 yr. Our study demonstrated that wiggle matching with optimal fitting based on either the weighted least-squares or maximum likelihood method can minimize the effect of scatter of age data due to reworking and burrowing of bivalves and thus improve the accuracy of age-depth models.

  3. Determining Stand Parameters from Uas-Based Point Clouds

    NASA Astrophysics Data System (ADS)

    Yilmaz, V.; Serifoglu, C.; Gungor, O.

    2016-06-01

    In Turkey, forest management plans are produced by terrestrial surveying techniques for 10 or 20 year periods, which can be considered quite long to maintain the sustainability of forests. For a successful forest management plan, it is necessary to collect accurate information about the stand parameters and store them in dynamic and robust databases. The position, number, height and closure of trees are among the most important stand parameters required for a forest management plan. Determining the position of each single tree is challenging in such an area consisting of too many interlocking trees. Hence, in this study, an object-based tree detection methodology has been developed in MATLAB programming language to determine the position of each tree top in a highly closed area. The developed algorithm uses the Canopy Height Model (CHM), which is computed from the Digital Terrain Model (DTM) and Digital Surface Model (DSM) generated by using the point cloud extracted from the images taken from a UAS (Unmanned Aerial System). The heights of trees have been determined by using the CHM. The closure of the trees has been determined with the written MATLAB script. The results show that the developed tree detection methodology detected more than 70% of the trees successfully. It can also be concluded that the stand parameters may be determined by using the UAS-based point clouds depending on the characteristics of the study area. In addition, determination of the stand parameters by using point clouds reduces the time needed to produce forest management plans.

  4. Age and Heat Stress as Determinants of Telomere Length in a Long-Lived Fish, the Siberian Sturgeon.

    PubMed

    Simide, Rémy; Angelier, Frédéric; Gaillard, Sandrine; Stier, Antoine

    2016-01-01

    Telomeres shorten at each cell division due to the end-replication problem but also in response to oxidative stress. Consequently, telomeres shorten with age in many endotherms, and this shortening is accelerated under stressful environmental conditions. Data in ectotherm vertebrates remain scarce so far, so our goal was to review existing data for fish and to test the influence of age and stress on telomere length in a very long-lived fish, the Siberian sturgeon (Acipenser baerii). Our review of the literature revealed age-related telomere shortening in approximately half of the published studies. In the Siberian sturgeon, we found a significant telomere shortening with age, both at the intraindividual level using red blood cells (-12.5% in 16 mo) and at the interindividual level using cross-sectional samples of fin over an age range of 8 yr. We also found that heat stress (30°C) significantly reduced telomere length by 15.0% after only 1 mo of exposure. Our results highlight that both age and stressful environmental conditions might be important determinants of telomere length in fish. PMID:27617363

  5. Age and Heat Stress as Determinants of Telomere Length in a Long-Lived Fish, the Siberian Sturgeon.

    PubMed

    Simide, Rémy; Angelier, Frédéric; Gaillard, Sandrine; Stier, Antoine

    2016-01-01

    Telomeres shorten at each cell division due to the end-replication problem but also in response to oxidative stress. Consequently, telomeres shorten with age in many endotherms, and this shortening is accelerated under stressful environmental conditions. Data in ectotherm vertebrates remain scarce so far, so our goal was to review existing data for fish and to test the influence of age and stress on telomere length in a very long-lived fish, the Siberian sturgeon (Acipenser baerii). Our review of the literature revealed age-related telomere shortening in approximately half of the published studies. In the Siberian sturgeon, we found a significant telomere shortening with age, both at the intraindividual level using red blood cells (-12.5% in 16 mo) and at the interindividual level using cross-sectional samples of fin over an age range of 8 yr. We also found that heat stress (30°C) significantly reduced telomere length by 15.0% after only 1 mo of exposure. Our results highlight that both age and stressful environmental conditions might be important determinants of telomere length in fish.

  6. Age of Zhoukoudian Homo erectus determined with (26)Al/(10)Be burial dating.

    PubMed

    Shen, Guanjun; Gao, Xing; Gao, Bin; Granger, Darryl E

    2009-03-12

    The age of Zhoukoudian Homo erectus, commonly known as 'Peking Man', has long been pursued, but has remained problematic owing to the lack of suitable dating methods. Here we report cosmogenic (26)Al/(10)Be burial dating of quartz sediments and artefacts from the lower strata of Locality 1 in the southwestern suburb of Beijing, China, where early representatives of Zhoukoudian Homo erectus were discovered. This study marks the first radioisotopic dating of any early hominin site in China beyond the range of mass spectrometric U-series dating. The weighted mean of six meaningful age measurements, 0.77 +/- 0.08 million years (Myr, mean +/- s.e.m.), provides the best age estimate for lower cultural layers 7-10. Together with previously reported U-series dating of speleothem calcite and palaeomagnetic stratigraphy, as well as sedimentological considerations, these layers may be further correlated to S6-S7 in Chinese loess stratigraphy or marine isotope stages (MIS) 17-19, in the range of approximately 0.68 to 0.78 Myr ago. These ages are substantially older than previously supposed and may imply early hominin's presence at the site in northern China through a relatively mild glacial period corresponding to MIS 18.

  7. The accumulation of stable cytogenetic rearrangements with age-determined by chromosome painting

    SciTech Connect

    Ramsey, M.J.; Lee, D.A.; Senft, J.R.; Briner, J.F.; Moore, D.H. II; Tucker, J.D.

    1994-12-31

    Chromosome painting is a rapid method of quantifying structural chromosomal rearrangements. The method is particularly useful for detecting stable aberrations which are difficult and expensive to quantify with classical methods. Translocations, being inherently stable, can be used as a biodosimeter for chronic and temporally-displaced exposure to radiation. Translocations may also be useful for quantifying chronic exposure to environmentally related agents which may result in an accumulation of cytogenetic damage with age. Because most chemical exposures are low and chronic, conventional cytogenetic methods are not expected to be informative. To understand the extent that age and lifestyle factors impact the frequency of stable aberrations, we used chromosome painting in healthy individuals who have not been occupationally or accidentally exposed to radiation or chemicals, and who have not received chemo- or radiotherapy. To date we have analyzed 15 umbilical cord bloods as well as peripheral blood samples from 83 adults aged up to 77 years. Because stable aberrations are rare in unexposed people, we have scored large numbers of cells from each subject. Thus far we have analyzed the equivalent of more than 78,000 metaphases from these 83 people, and have observed an average of 0.75% of cells with translocations or stable insertions. A significant curvilinear relationship with age is apparent (R{sup 2} = 0.69, p <0.00001). No effect with smoking was seen.

  8. Socio-economic determinants of age differences between spouses in Bangladesh.

    PubMed

    Ahmed, A U

    1989-01-01

    "This study examines socio-economic differentials in age differences between spouses in Bangladesh. The variables considered for the analysis are bride's current and childhood residences, education, work status before and after marriage; and groom's childhood residence, education and occupation. Among these variables, childhood residence, education and occupation evince the strongest differentials." (SUMMARY IN FRE AND ITA)

  9. LIFESTYLE DETERMINANTS OF C-REACTIVE PROTEIN IN MIDDLE-AGED, URBAN CHINESE MEN

    PubMed Central

    Villegas, Raquel; Xiang, Yong-Bing; Cai, Hui; Elasy, Tom; Cai, Qiuyin; Zhang, Xianglan; Fazio, Sergio; Linton, MacRae; Li, Honglan; Xu, Wang Hong; Yang, Gong; Zheng, Wei; Shu, Xiao-Ou

    2011-01-01

    Background Increased levels of C-reactive protein (CRP), common in aging populations, are associated with higher risk for chronic diseases, including diabetes and coronary heart disease. The aim of this study was to investigate associations between lifestyle factors and high CRP among middleaged men living in Shanghai, China. PMID:21111583

  10. Socio-Demographic Determinants of Economic Growth: Age-Structure, Preindustrial Heritage and Sociolinguistic Integration

    ERIC Educational Resources Information Center

    Crenshaw, Edward; Robison, Kristopher

    2010-01-01

    This study establishes a socio-demographic theory of international development derived from selected classical and contemporary sociological theories. Four hypotheses are tested: (1. population growth's effect on development depends on age-structure; (2. historic population density (used here as an indicator of preindustrial social complexity)…

  11. Aging is a more significant determinant of hepatic DNA methylation patterns than a western style diet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated how DNA methylation patterns change with aging and a Western style diet (WSD) in the liver. 2-month old male C57BL/6 mice were randomized to control diet (CD) or WSD for either the following 6 (young) or 18 months (old). WSD is high in fat and low in fiber, vitamins and minerals. Met...

  12. Determining Evidence-Based Practices in Special Education

    ERIC Educational Resources Information Center

    Cook, Bryan G.; Tankersley, Melody; Landrum, Timothy J.

    2009-01-01

    Determining evidence-based practices is a complicated enterprise that requires analyzing the methodological quality and magnitude of the available research supporting specific practices. This article reviews criteria and procedures for identifying what works in the fields of clinical psychology, school psychology, and general education; and it…

  13. Quicky location determination based on geographic keywords of natural language

    NASA Astrophysics Data System (ADS)

    Guo, Danhuai; Cui, Weihong

    2007-06-01

    In location determination based on natural language, it is common to find the location by describing relationship between the undetermined position and one or several determined position. That indicates that the uncertainty of location determination processing is derived from the one of natural language procedure, the one of spatial position description and the one of spatial relationship description. Most of current researches and regular GIS software take certainty as prerequisite and try to avoid uncertainty and its influence. The research reported in this paper is an attempt to create a new combing method of Artificial Intelligence (AI), Fuzzy set theory and spatial information science named Quickly Location Determination based on Geographic Keywords (QLDGK) to rise to the challenge of location searching technique based on natural language. QLDGK have two technical gists. The first one is geographic-keywords-library and special natural-language-separation-model-library that increases the language processing efficiency. The second one is fuzzy theory based definition of spatial relationship, spatial metric and spatial orientation that extends the searching scope and defines variant confidences on variant searching outcome. QLDGK takes consideration on both higher query efficiency and the lower omission rate. The above method has been proved workable and efficient by QLDGK prototype system which was tested by about 12000 emergency call reports from K-city, Southwest of China, and achieved the test result with 78% accuracy in highest confidence and 8% omitting ration.

  14. 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

  15. Ages of flow units in the lunar nearside maria based on Lunar Orbiter IV photographs

    NASA Technical Reports Server (NTRS)

    Boyce, J. M.

    1976-01-01

    A map dividing the lunar nearside maria into six units each of uniform age was compiled from Lunar Orbiter IV photographs. Relative ages were determined using a crater morphology technique. Relative ages were then converted to absolute ages by comparison to a curve calibrated from Apollo and Luna sample data; three of the six units, including the two youngest (about 3.1 and 2.6 b.y. old), were not sampled by Apollo or Luna. Vast regions in the western maria are covered by these young flows. The old flows (about 3.75 b.y. in age) are found to occur mostly in the eastern maria. A comparison of the age units derived from these data with those units derived from other remote-sensing data provide good agreement in the location of unit boundaries. These data also indicate that the emplacement history of mare basalt types is more complex than was earlier thought.

  16. Bone age assessment by content-based image retrieval and case-based reasoning

    NASA Astrophysics Data System (ADS)

    Fischer, Benedikt; Welter, Petra; Grouls, Christoph; Günther, Rolf W.; Deserno, Thomas M.

    2011-03-01

    Skeletal maturity is assessed visually by comparing hand radiographs to a standardized reference image atlas. Most common are the methods by Greulich & Pyle and Tanner & Whitehouse. For computer-aided diagnosis (CAD), local image regions of interest (ROI) such as the epiphysis or the carpal areas are extracted and evaluated. Heuristic approaches trying to automatically extract, measure and classify bones and distances between bones suffer from the high variability of biological material and the differences in bone development resulting from age, gender and ethnic origin. Content-based image retrieval (CBIR) provides a robust solution without delineating and measuring bones. In this work, epiphyseal ROIs (eROIS) of a hand radiograph are compared to previous cases with known age, mimicking a human observer. Leaving-one-out experiments are conducted on 1,102 left hand radiographs and 15,428 metacarpal and phalangeal eROIs from the publicly available USC hand atlas. The similarity of the eROIs is assessed by a combination of cross-correlation, image distortion model, and Tamura texture features, yielding a mean error rate of 0.97 years and a variance of below 0.63 years. Furthermore, we introduce a publicly available online-demonstration system, where queries on the USC dataset as well as on uploaded radiographs are performed for instant CAD. In future, we plan to evaluate physician with CBIR-CAD against physician without CBIR-CAD rather than physician vs. CBIR-CAD.

  17. Tile-based Level of Detail for the Parallel Age

    SciTech Connect

    Niski, K; Cohen, J D

    2007-08-15

    Today's PCs incorporate multiple CPUs and GPUs and are easily arranged in clusters for high-performance, interactive graphics. We present an approach based on hierarchical, screen-space tiles to parallelizing rendering with level of detail. Adapt tiles, render tiles, and machine tiles are associated with CPUs, GPUs, and PCs, respectively, to efficiently parallelize the workload with good resource utilization. Adaptive tile sizes provide load balancing while our level of detail system allows total and independent management of the load on CPUs and GPUs. We demonstrate our approach on parallel configurations consisting of both single PCs and a cluster of PCs.

  18. DNA methylation-based measures of biological age: meta-analysis predicting time to death

    PubMed Central

    Chen, Brian H.; Marioni, Riccardo E.; Colicino, Elena; Peters, Marjolein J.; Ward-Caviness, Cavin K.; Tsai, Pei-Chien; Roetker, Nicholas S.; Just, Allan C.; Demerath, Ellen W.; Guan, Weihua; Bressler, Jan; Fornage, Myriam; Studenski, Stephanie; Vandiver, Amy R.; Moore, Ann Zenobia; Tanaka, Toshiko; Kiel, Douglas P.; Liang, Liming; Vokonas, Pantel; Schwartz, Joel; Lunetta, Kathryn L.; Murabito, Joanne M.; Bandinelli, Stefania; Hernandez, Dena G.; Melzer, David; Nalls, Michael; Pilling, Luke C.; Price, Timothy R.; Singleton, Andrew B.; Gieger, Christian; Holle, Rolf; Kretschmer, Anja; Kronenberg, Florian; Kunze, Sonja; Linseisen, Jakob; Meisinger, Christine; Rathmann, Wolfgang; Waldenberger, Melanie; Visscher, Peter M.; Shah, Sonia; Wray, Naomi R.; McRae, Allan F.; Franco, Oscar H.; Hofman, Albert; Uitterlinden, André G.; Absher, Devin; Assimes, Themistocles; Levine, Morgan E.; Lu, Ake T.; Tsao, Philip S.; Hou, Lifang; Manson, JoAnn E.; Carty, Cara L.; LaCroix, Andrea Z.; Reiner, Alexander P.; Spector, Tim D.; Feinberg, Andrew P.; Levy, Daniel; Baccarelli, Andrea; van Meurs, Joyce; Bell, Jordana T.; Peters, Annette; Deary, Ian J.; Pankow, James S.; Ferrucci, Luigi; Horvath, Steve

    2016-01-01

    Estimates of biological age based on DNA methylation patterns, often referred to as “epigenetic age”, “DNAm age”, have been shown to be robust biomarkers of age in humans. We previously demonstrated that independent of chronological age, epigenetic age assessed in blood predicted all-cause mortality in four human cohorts. Here, we expanded our original observation to 13 different cohorts for a total sample size of 13,089 individuals, including three racial/ethnic groups. In addition, we examined whether incorporating information on blood cell composition into the epigenetic age metrics improves their predictive power for mortality. All considered measures of epigenetic age acceleration were predictive of mortality (p≤8.2×10−9), independent of chronological age, even after adjusting for additional risk factors (p<5.4×10−4), and within the racial/ethnic groups that we examined (non-Hispanic whites, Hispanics, African Americans). Epigenetic age estimates that incorporated information on blood cell composition led to the smallest p-values for time to death (p=7.5×10−43). Overall, this study a) strengthens the evidence that epigenetic age predicts all-cause mortality above and beyond chronological age and traditional risk factors, and b) demonstrates that epigenetic age estimates that incorporate information on blood cell counts lead to highly significant associations with all-cause mortality. PMID:27690265

  19. DETERMINING THE EFFECTS OF RADIATION ON AGING CONCRETE STRUCTURES OF NUCLEAR REACTORS

    SciTech Connect

    Serrato, M.

    2010-01-29

    The U.S. Department of Energy Office of Environmental Management (DOE-EM) is responsible for the Decontamination and Decommissioning (D&D) of nuclear facilities throughout the DOE Complex. Some of these facilities will be completely dismantled, while others will be partially dismantled and the remaining structure will be stabilized with cementitious fill materials. The latter is a process known as In-Situ Decommissioning (ISD). The ISD decision process requires a detailed understanding of the existing facility conditions, and operational history. System information and material properties are need for aged nuclear facilities. This literature review investigated the properties of aged concrete structures affected by radiation. In particular, this review addresses the Savannah River Site (SRS) isotope production nuclear reactors. The concrete in the reactors at SRS was not seriously damaged by the levels of radiation exposure. Loss of composite compressive strength was the most common effect of radiation induced damage documented at nuclear power plants.

  20. Geochemical implications from Sr isotopes and K-Ar age determinations for the cook-austral islands chain

    NASA Astrophysics Data System (ADS)

    Matsuda, Jun-Ichi; Notsu, Kenji; Okano, Jun; Yaskawa, Katsumi; Chungue, Leonard

    1984-04-01

    Sr isotopes and K-Ar ages were determined for volcanic rocks from three islands, Samoa, Rarotonga and Rurutu in the Austral-Gilbert-Marshall chain. We have established that Rurutu originated from the same "hot spot" as Tubuai and Raivavae in the Cook-Austral chain as indicated by its 11 m.y. K-Ar age and ( {87Sr }/{86Sr }) ratios. The ( {87Sr }/{86Sr }) ratios for Rurutu, Tubuai and Raivavae lie in the restricted range 0.7026-0.7035. K-Ar ages of all volcanic rocks from Samoa and Rarotonga are all less than 4 m.y. and their ( {87Sr }/{86Sr }) ratios are much higher than those in Rurutu, Tubuai and Raivavae. These findings suggest that Samoa and Rarotonga did not originate in a single hot spot for the Cook-Austral islands.

  1. Interaction between PNPLA3 I148M Variant and Age at Infection in Determining Fibrosis Progression in Chronic Hepatitis C

    PubMed Central

    Aghemo, Alessio; Cheroni, Cristina; D'Ambrosio, Roberta; Pedrazzini, Michele; Marabita, Francesco; Donnici, Lorena; Maggioni, Marco; Fargion, Silvia; Colombo, Massimo; De Francesco, Raffaele; Valenti, Luca

    2014-01-01

    Background and Aims The PNPLA3 I148M sequence variant favors hepatic lipid accumulation and confers susceptibility to hepatic fibrosis and hepatocellular carcinoma. The aim of this study was to estimate the effect size of homozygosity for the PNPLA3 I148M variant (148M/M) on the fibrosis progression rate (FPR) and the interaction with age at infection in chronic hepatitis C (CHC). Methods FPR was estimated in a prospective cohort of 247 CHC patients without alcohol intake and diabetes, with careful estimation of age at infection and determination of fibrosis stage by Ishak score. Results Older age at infection was the strongest determinant of FPR (p<0.0001). PNPLA3 148M/M was associated with faster FPR in individuals infected at older age (above the median, 21 years; −0.64±0.2, n = 8 vs. −0.95±0.3, n = 166 log10 FPR respectively; p = 0.001; confirmed for lower age thresholds, p<0.05), but not in those infected at younger age (p = ns). The negative impact of PNPLA3 148M/M on fibrosis progression was more marked in subjects at risk of altered hepatic lipid metabolism (those with grade 2–3 steatosis, genotype 3, and overweight; p<0.05). At multivariate analysis, PNPLA3 148M/M was associated with FPR (incremental effect 0.08±0.03 log10 fibrosis unit per year; p = 0.022), independently of several confounders, and there was a significant interaction between 148M/M and older age at infection (p = 0.025). The association between 148M/M and FPR remained significant even after adjustment for steatosis severity (p = 0.032). Conclusions We observed an interaction between homozygosity for the PNPLA3 I148M variant and age at infection in determining fibrosis progression in CHC patients. PMID:25171251

  2. [Influence of age on blood glucose levels: percentile reference intervals determined on ambulatory patients].

    PubMed

    Sapigni, T; Astolfi, G; Cavallini, L; Cremonini, F

    1981-06-15

    Data of routine chemical and hematological laboratory tests regarding outpatients were collected in four different hospitals of the provinces of Ferrara, Rovigo and Bologna. Data of about 1500 subjects per hospital were cumulated without preliminary selection of patients; sex, age and pregnancy status were also recorded. At the end of the collection, the second (and third) record of the same patient was discarded; only those referring to the first examination were retained. In this report we consider only the values of the blood sugar level which were obtained by enzymatic methods. Descriptive statistics and regression analysis were performed utilizing a CDC CYBER 70/76 computer. The means and the variances of the data collected at the four hospital laboratories were very similar (Tab 1). The interlaboratory analysis of variance was poorly significant. All frequency distributions were leptocurtic and skewed to the right (Fig. 1). The blood sugar level tend to increase with age (Tab. 2). This correlation is graphically depicted in a two-dimensional plot (Fig 2) in which the regression line and the 2, 5 and 97,5 percentile levels corrected for age were also reported. We think that this diagram may be more helpful to the clinicians interpreting laboratory results than the usual "normal values". PMID:7284101

  3. Controlling for Landform Age When Determining the Settlement History of the Kuril Islands

    PubMed Central

    MacInnes, Breanyn; Fitzhugh, Ben; Holman, Darryl

    2014-01-01

    Archaeological investigations of settlement patterns in dynamic landscapes can be strongly biased by the evolution of the Earth’s surface. The Kuril Island volcanic arc exemplifies such a dynamic landscape, where landscape-modifying geological forces were active during settlement, including sea-level changes, tectonic emergence, volcanic eruptive processes, coastal aggradation, and dune formation. With all these ongoing processes, in this paper we seek to understand how new landscape formation in the Holocene might bias archaeological interpretations of human settlement in the Kurils. Resolving this issue is fundamental to any interpretation of human settlement history derived from the distribution and age of archaeological sites from the region. On the basis of a comparison of landform ages and earliest archaeological occupation ages on those landforms, we conclude that landform creation did not significantly bias our aggregate archaeological evidence for earliest settlement. Some sections of the archipelago have larger proportions of landform creation dates closer to archaeological evidence of settlement and undoubtedly some archaeological sites have been lost to geomorphic processes. However, comparisons between regions reveal comparable archaeological establishment patterns irrespective of geomorphic antiquity. PMID:25684855

  4. Age determination of vessel wall hematoma in spontaneous cervical artery dissection: A multi-sequence 3T Cardiovascular Magnetic resonance study

    PubMed Central

    2011-01-01

    Background Previously proposed classifications for carotid plaque and cerebral parenchymal hemorrhages are used to estimate the age of hematoma according to its signal intensities on T1w and T2w MR images. Using these classifications, we systematically investigated the value of cardiovascular magnetic resonance (CMR) in determining the age of vessel wall hematoma (VWH) in patients with spontaneous cervical artery dissection (sCAD). Methods 35 consecutive patients (mean age 43.6 ± 9.8 years) with sCAD received a cervical multi-sequence 3T CMR with fat-saturated black-blood T1w-, T2w- and TOF images. Age of sCAD was defined as time between onset of symptoms (stroke, TIA or Horner's syndrome) and the CMR scan. VWH were categorized into hyperacute, acute, early subacute, late subacute and chronic based on their signal intensities on T1w- and T2w images. Results The mean age of sCAD was 2.0, 5.8, 15.7 and 58.7 days in patients with acute, early subacute, late subacute and chronic VWH as classified by CMR (p < 0.001 for trend). Agreement was moderate between VWH types in our study and the previously proposed time scheme of signal evolution for cerebral hemorrhage, Cohen's kappa 0.43 (p < 0.001). There was a strong agreement of CMR VWH classification compared to the time scheme which was proposed for carotid intraplaque hematomas with Cohen's kappa of 0.74 (p < 0.001). Conclusions Signal intensities of VWH in sCAD vary over time and multi-sequence CMR can help to determine the age of an arterial dissection. Furthermore, findings of this study suggest that the time course of carotid hematomas differs from that of cerebral hematomas. PMID:22122756

  5. Using a Novel Absolute Ontogenetic Age Determination Technique to Calculate the Timing of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis.

    PubMed

    Wysocki, M Aleksander; Feranec, Robert S; Tseng, Zhijie Jack; Bjornsson, Christopher S

    2015-01-01

    Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month). Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates absolute ontogenetic age ranges of tooth development and eruption in S. fatalis. The timing of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo). Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for absolute ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the timing of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation.

  6. Using a Novel Absolute Ontogenetic Age Determination Technique to Calculate the Timing of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis

    PubMed Central

    Wysocki, M. Aleksander; Feranec, Robert S.; Tseng, Zhijie Jack; Bjornsson, Christopher S.

    2015-01-01

    Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month). Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates absolute ontogenetic age ranges of tooth development and eruption in S. fatalis. The timing of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo). Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for absolute ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the timing of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation. PMID:26132165

  7. 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

  8. 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.

  9. 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.

  10. A clinic-based study of refractive errors, strabismus, and amblyopia in pediatric age-group

    PubMed Central

    Al-Tamimi, Elham R.; Shakeel, Ayisha; Yassin, Sanaa A.; Ali, Syed I.; Khan, Umar A.

    2015-01-01

    Purpose: The purpose of this cross-sectional observational study was to determine the distribution and patterns of refractive errors, strabismus, and amblyopia in children seen at a pediatric eye care. Materials and Methods: The study was conducted in a Private Hospital in Dammam, Kingdom of Saudi Arabia, from March to July 2013. During this period, a total of 1350 children, aged 1–15 years were seen at this Center's Pediatric Ophthalmology Unit. All the children underwent complete ophthalmic examination with cycloplegic refraction. Results: Refractive errors accounted for 44.4% of the cases, the predominant refractive error being hypermetropia which represented 83%. Strabismus and amblyopia were present in 38% and 9.1% of children, respectively. Conclusions: In this clinic-based study, the focus was on the frequency of refractive errors, strabismus, and amblyopia which were considerably high. Hypermetropia was the predominant refractive error in contrast to other studies in which myopia was more common. This could be attributed to the criteria for sample selection since it was clinic-based rather than a population-based study. However, it is important to promote public education on the significance of early detection of refractive errors, and have periodic screening in schools. PMID:26392796

  11. 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

  12. Genome-Based Microbial Taxonomy Coming of Age.

    PubMed

    Hugenholtz, Philip; Skarshewski, Adam; Parks, Donovan H

    2016-01-01

    Reconstructing the complete evolutionary history of extant life on our planet will be one of the most fundamental accomplishments of scientific endeavor, akin to the completion of the periodic table, which revolutionized chemistry. The road to this goal is via comparative genomics because genomes are our most comprehensive and objective evolutionary documents. The genomes of plant and animal species have been systematically targeted over the past decade to provide coverage of the tree of life. However, multicellular organisms only emerged in the last 550 million years of more than three billion years of biological evolution and thus comprise a small fraction of total biological diversity. The bulk of biodiversity, both past and present, is microbial. We have only scratched the surface in our understanding of the microbial world, as most microorganisms cannot be readily grown in the laboratory and remain unknown to science. Ground-breaking, culture-independent molecular techniques developed over the past 30 years have opened the door to this so-called microbial dark matter with an accelerating momentum driven by exponential increases in sequencing capacity. We are on the verge of obtaining representative genomes across all life for the first time. However, historical use of morphology, biochemical properties, behavioral traits, and single-marker genes to infer organismal relationships mean that the existing highly incomplete tree is riddled with taxonomic errors. Concerted efforts are now needed to synthesize and integrate the burgeoning genomic data resources into a coherent universal tree of life and genome-based taxonomy. PMID:26988968

  13. Nanoscale dynamics and aging of fibrous peptide-based gels

    SciTech Connect

    Dudukovic, Nikola A.; Zukoski, Charles F.

    2014-10-28

    Solutions of the aromatic dipeptide derivative molecule fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) in dimethyl sulfoxide produce fibrous gels when mixed with water. We study the evolution of density fluctuations of this three-component system using X-ray photon correlation spectroscopy (XPCS) and compare these results to the macroscopic rheology of the gels and optical observations of the microstructure evolution. At the investigated scattering angles, the intensity autocorrelation functions do not follow behavior expected for simple diffusion of individual Fmoc-FF molecules localized within cages of nearest neighbors. Instead, the dynamics are associated with density fluctuations on length scales of ∼10–100 nm arising from disaggregation and reformation of fibers, leading to an increasingly uniform network. This process is correlated with the growth of the elastic modulus, which saturates at long times. Autocorrelation functions and relaxation times acquired from XPCS measurements are consistent with relaxation rates of structures at dynamic equilibrium. This study provides further support to the concept of exploring peptide-based gelators as valence-limited patchy particles capable of forming equilibrium gels.

  14. Nanoscale dynamics and aging of fibrous peptide-based gels.

    PubMed

    Dudukovic, Nikola A; Zukoski, Charles F

    2014-10-28

    Solutions of the aromatic dipeptide derivative molecule fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) in dimethyl sulfoxide produce fibrous gels when mixed with water. We study the evolution of density fluctuations of this three-component system using X-ray photon correlation spectroscopy (XPCS) and compare these results to the macroscopic rheology of the gels and optical observations of the microstructure evolution. At the investigated scattering angles, the intensity autocorrelation functions do not follow behavior expected for simple diffusion of individual Fmoc-FF molecules localized within cages of nearest neighbors. Instead, the dynamics are associated with density fluctuations on length scales of ~10-100 nm arising from disaggregation and reformation of fibers, leading to an increasingly uniform network. This process is correlated with the growth of the elastic modulus, which saturates at long times. Autocorrelation functions and relaxation times acquired from XPCS measurements are consistent with relaxation rates of structures at dynamic equilibrium. This study provides further support to the concept of exploring peptide-based gelators as valence-limited patchy particles capable of forming equilibrium gels.

  15. Assessment of MRI-Based Automated Fetal Cerebral Cortical Folding Measures in Prediction of Gestational Age in the Third Trimester

    PubMed Central

    Wu, J.; Awate, S.P.; Licht, D.J.; Clouchoux, C.; du Plessis, A.J.; Avants, B.B.; Vossough, A.; Gee, J.C.; Limperopoulos, C.

    2016-01-01

    BACKGROUND AND PURPOSE Traditional methods of dating a pregnancy based on history or sonographic assessment have a large variation in the third trimester. We aimed to assess the ability of various quantitative measures of brain cortical folding on MR imaging in determining fetal gestational age in the third trimester. MATERIALS AND METHODS We evaluated 8 different quantitative cortical folding measures to predict gestational age in 33 healthy fetuses by using T2-weighted fetal MR imaging. We compared the accuracy of the prediction of gestational age by these cortical folding measureswiththeaccuracyofpredictionbybrainvolumemeasurementandbyapreviouslyreportedsemiquantitativevisualscaleofbrain maturity. Regression models were constructed, and measurement biases and variances were determined via a cross-validation procedure. RESULTS The cortical folding measures are accurate in the estimation and prediction of gestational age (mean of the absolute error, 0.43 ± 0.45 weeks) and perform better than (P = .024) brain volume (mean of the absolute error, 0.72 ± 0.61 weeks) or sonography measures (SDs approximately 1.5 weeks, as reported in literature). Prediction accuracy is comparable with that of the semiquantitative visual assessment score (mean, 0.57 ± 0.41 weeks). CONCLUSIONS Quantitative cortical folding measures such as global average curvedness can be an accurate and reliable estimator of gestational age and brain maturity for healthy fetuses in the third trimester and have the potential to be an indicator of brain-growth delays for at-risk fetuses and preterm neonates. PMID:26045578

  16. Blood Glucose, Diet-Based Glycemic Load and Cognitive Aging Among Dementia-Free Older Adults

    PubMed Central

    Andel, Ross; McEvoy, Cathy; Dahl Aslan, Anna K.; Finkel, Deborah; Pedersen, Nancy L.

    2015-01-01

    Background. Although evidence indicates that Type II Diabetes is related to abnormal brain aging, the influence of elevated blood glucose on long-term cognitive change is unclear. In addition, the relationship between diet-based glycemic load and cognitive aging has not been extensively studied. The focus of this study was to investigate the influence of diet-based glycemic load and blood glucose on cognitive aging in older adults followed for up to 16 years. Methods. Eight-hundred and thirty-eight cognitively healthy adults aged ≥50 years (M = 63.1, SD = 8.3) from the Swedish Adoption/Twin Study of Aging were studied. Mixed effects growth models were utilized to assess overall performance and change in general cognitive functioning, perceptual speed, memory, verbal ability, and spatial ability as a function of baseline blood glucose and diet-based glycemic load. Results. High blood glucose was related to poorer overall performance on perceptual speed as well as greater rates of decline in general cognitive ability, perceptual speed, verbal ability, and spatial ability. Diet-based glycemic load was related to poorer overall performance in perceptual speed and spatial ability. Conclusion. Diet-based glycemic load and, in particular, elevated blood glucose appear important for cognitive performance/cognitive aging. Blood glucose control (perhaps through low glycemic load diets) may be an important target in the detection and prevention of age-related cognitive decline. PMID:25149688

  17. Equilibrium population dynamics when mating is by mutual choice based on age.

    PubMed

    Alpern, Steve; Katrantzi, Ioanna; Ramsey, David

    2014-06-01

    We consider a steady state model of mutual mate choice in which an individual's mate preferences depend on his/her age, and the preferences are over the ages of prospective mates of the opposite sex. We present a discrete time (and age) model corresponding to successive mating seasons. Males are fertile for m periods (corresponding to 'age' i=1 to m) and females for n≤m periods (they have ages j=1 to n), which is all that distinguishes the sexes. Although we can deal with arbitrary preferences, we concentrate on a simple fertility model where the common utility to a male age i and female age j who mate is the number K=min(m-i+1,n-j+1) of future periods of joint fertility. The incoming sex ratio R of age 1 males to age 1 females is given exogenously. In each period individuals are randomly (non assortatively) matched and form a mated couple by mutual consent; otherwise they go into the next period unmated and older. We derive properties of equilibrium threshold acceptance strategies and establish the existence of time-invariant age distributions. Our methods determine the age distribution of couples at marriage (mating) and the population sex ratio (OSR) at equilibrium. Since this can be determined empirically in a population, our model can be used to rule out most systems of age preferences (those not consistent with the observed distribution). This extends earlier models of mutual choice with one dimensional types of Alpern and Reyniers [1999. Strategic mating with homotypic preferences. J. Theor. Biol. 198, 71-88; 2005. Strategic mating with common preferences. J. Theor. Biol. 237, 337-354] where individuals sought, respectively, individuals with similar or high types, but in those models an individual's type was fixed over time. Under the simple fertility model, at equilibrium the maximum age of an acceptable partner is increasing in the age of the searcher. Our results relate to discussions in the literature regarding optimal parental age differences, age

  18. Equilibrium population dynamics when mating is by mutual choice based on age.

    PubMed

    Alpern, Steve; Katrantzi, Ioanna; Ramsey, David

    2014-06-01

    We consider a steady state model of mutual mate choice in which an individual's mate preferences depend on his/her age, and the preferences are over the ages of prospective mates of the opposite sex. We present a discrete time (and age) model corresponding to successive mating seasons. Males are fertile for m periods (corresponding to 'age' i=1 to m) and females for n≤m periods (they have ages j=1 to n), which is all that distinguishes the sexes. Although we can deal with arbitrary preferences, we concentrate on a simple fertility model where the common utility to a male age i and female age j who mate is the number K=min(m-i+1,n-j+1) of future periods of joint fertility. The incoming sex ratio R of age 1 males to age 1 females is given exogenously. In each period individuals are randomly (non assortatively) matched and form a mated couple by mutual consent; otherwise they go into the next period unmated and older. We derive properties of equilibrium threshold acceptance strategies and establish the existence of time-invariant age distributions. Our methods determine the age distribution of couples at marriage (mating) and the population sex ratio (OSR) at equilibrium. Since this can be determined empirically in a population, our model can be used to rule out most systems of age preferences (those not consistent with the observed distribution). This extends earlier models of mutual choice with one dimensional types of Alpern and Reyniers [1999. Strategic mating with homotypic preferences. J. Theor. Biol. 198, 71-88; 2005. Strategic mating with common preferences. J. Theor. Biol. 237, 337-354] where individuals sought, respectively, individuals with similar or high types, but in those models an individual's type was fixed over time. Under the simple fertility model, at equilibrium the maximum age of an acceptable partner is increasing in the age of the searcher. Our results relate to discussions in the literature regarding optimal parental age differences, age

  19. The impact of base excision DNA repair in age-related neurodegenerative diseases.

    PubMed

    Leandro, Giovana S; Sykora, Peter; Bohr, Vilhelm A

    2015-06-01

    The aging process and several age-related neurodegenerative disorders have been linked to elevated levels of DNA damage induced by ROS and deficiency in DNA repair mechanisms. DNA damage induced by ROS is a byproduct of cellular respiration and accumulation of damage over time, is a fundamental aspect of a main theory of aging. Mitochondria have a pivotal role in generating cellular oxidative stress, and mitochondrial dysfunction has been associated with several diseases. DNA base excision repair is considered the major pathway for repair of oxidized bases in DNA both in the nuclei and in mitochondria, and in neurons this mechanism is particularly important because non-diving cells have limited back-up DNA repair mechanisms. An association between elevated oxidative stress and a decrease in BER is strongly related to the aging process and has special relevance in age-related neurodegenerative diseases. Here, we review the role of DNA repair in aging, focusing on the implications of the DNA base excision repair pathways and how alterations in expression of these DNA repair proteins are related to the aging process and to age-related neurodegenerative diseases.

  20. Radiological age estimation: based on third molar mineralization and eruption in Turkish children and young adults.

    PubMed

    Karadayi, Beytullah; Kaya, Ahsen; Kolusayın, Melek Ozlem; Karadayi, Sükriye; Afsin, Hüseyin; Ozaslan, Abdi

    2012-11-01

    Radiographic evaluation of mineralization and eruption stages of third molars using dental panoramic radiographies can be an efficient tool for chronological age estimation in both forensic sciences and legal medicine. The third molar tooth is utilized for dental age estimation about the age span of 15-23 years because it represents the only tooth still in development. The aim of this study is to obtain and analyze data regarding third molar development and eruption in Turkish population for dental age estimation. A total of 744 dental panoramic radiographies of 394 female and 350 male subjects aged between 8 and 22 years were examined. Third molar development was determined according to the Nolla classification system, and eruption was assessed relative to the alveolar bone level. Mandibular and maxillary third molars were generally found at similar stages of development on both sides. Nolla stage 6 (completed crown calcification) was reached at around the age of 15 in both maxillary and mandibular third molars in both sexes. Alveolar emergence was at around the age of 16 in males and around age of 17 in females. Although third molars' eruption shows greater variability than development of third molars, data which were obtained from this study about eruption of these teeth can be supportive to development data for age estimation.

  1. Genetic determinants of fibro-osseous lesions in aged inbred mice.

    PubMed

    Berndt, Annerose; Ackert-Bicknell, Cheryl; Silva, Kathleen A; Kennedy, Victoria E; Sundberg, Beth A; Cates, Justin M; Schofield, Paul N; Sundberg, John P

    2016-02-01

    Fibro-osseous lesions in mice are progressive aging changes in which the bone marrow is replaced to various degrees by fibrovascular stroma and bony trabeculae in a wide variety of bones. The frequency and severity varied greatly among 28 different inbred mouse stains, predominantly affecting females, ranging from 0% for 10 strains to 100% for KK/HlJ and NZW/LacJ female mice. Few lesions were observed in male mice and for 23 of the strains, no lesions were observed in males for any of the cohorts. There were no significant correlations between strain-specific severities of fibro-osseous lesions and ovarian (r=0.11; P=0.57) or endometrial (r=0.03; P=0.89) cyst formation frequency or abnormalities in parathyroid glands. Frequency of fibro-osseous lesions was most strongly associated (P<10(-6)) with genome variations on chromosome (Chr) 8 at 90.6 and 90.8Mb (rs33108071, rs33500669; P=5.0·10(-10), 1.3·10(-6)), Chr 15 at 23.6 and 23.8Mb (rs32087871, rs45770368; P=7.3·10(-7), 2.7·10(-6)), and Chr 19 at 33.2, 33.4, and 33.6Mb (rs311004232, rs30524929, rs30448815; P=2.8·10(-6), 2.8·10(-6), 2.8·10(-6)) in genome-wide association studies (GWAS). The relatively large number of candidate genes identified in the GWAS analyses suggests that this may be an extremely complex polygenic disease. These results indicate that fibro-osseous lesions are surprisingly common in many inbred strains of laboratory mice as they age. While this presents little problem in most studies that utilize young animals, it may complicate aging studies, particularly those focused on bone. PMID:26589134

  2. Track studies of samples 72255 and 72275. [age determination for lunar rocks

    NASA Technical Reports Server (NTRS)

    Hutcheon, I. D.

    1974-01-01

    Optical microscopic studies of two intermediate pieces of 72255, located 1 to 3 cm below the surface, indicate an upper limit to the track exposure age of 15 to 20 m.y. A striking feature of the track studies of breccias 72255 and 72275 is the peculiar etching behavior of many of the feldspar and olivine crystals. After standard etching procedures, crystal surfaces are frequently irregular and bumpy, presumably owing to nonuniform dissolution of the surface. Although this effect was not observed in feldspars or olivines in samples from other missions, it is apparently widespread among Apollo 17 samples.

  3. Paleoglaciation of the Tibetan Plateau based on exposure ages and ELA depression estimates

    NASA Astrophysics Data System (ADS)

    Heyman, Jakob

    2014-05-01

    The Tibetan Plateau holds a major part of all glaciers outside the polar regions and an ample record of past glaciations. The glacial history of the Tibetan Plateau has attracted significant interest, with a large body of research investigating the extent, timing, and climatic implications of past glaciations. Here I present an extensive compilation of exposure ages and equilibrium line altitude (ELA) depression estimates from glacial deposits across the Tibetan Plateau to address the timing and degree of past glaciations. I compiled Be-10 exposure age data for a total of 1877 samples and recalculated exposure ages using an updated (lower) global Be-10 production rate. All samples were organized in groups of individual glacial deposits where each deposit represents one glacial event enabling evaluation of the exposure age clustering. For each glacial deposit I estimated the ELA depression based on a simple toe to headwall ratio approach using Google Earth. To discriminate good (well-clustered) from poor (scattered) exposure age groups the glacial deposits were divided into three groups based on exposure age clustering. A major part of the glacial deposits have scattered exposure ages affected by prior or incomplete exposure, complicating exposure age interpretations. The well-clustered exposure age groups are primarily from mountain ranges along the margins of the Tibetan Plateau with a main peak in age between 10 and 30 ka, indicating glacial advances during the global last glacial maximum (LGM). A large number of exposure ages older than 30 ka indicates maximum glaciation predating the LGM, but the exposure age scatter generally prohibits accurate definition of the glacial chronology. The ELA depression estimates scatter significantly, but a major part is remarkably low. Average ELA depressions of 333 ± 191 m for the LGM and 494 ± 280 m for the pre-LGM exposure indicate restricted glacier expansion and limited glacial cooling.

  4. Recent methods for the determination of peroxide-based explosives.

    PubMed

    Schulte-Ladbeck, Rasmus; Vogel, Martin; Karst, Uwe

    2006-10-01

    In the last few years, the need to determine peroxide-based explosives in solid samples and air samples has resulted in the development of a series of new analytical methods for triacetonetriperoxide (TATP, acetone peroxide) and hexamethylenetriperoxidediamine (HMTD). In this review, after a short introduction describing the state of the art in the field, these new analytical methods are critically discussed. Particular emphasis is placed on spectroscopic and mass spectrometric methods as well as on chromatographic techniques with selective detection schemes. The potential of these methods to analyse unknown solid samples that might contain one or more of the explosives and to analyse peroxide-based explosives in air is evaluated.

  5. Variations in Community Prevalence and Determinants of Recreational and Utilitarian Walking in Older Age

    PubMed Central

    Procter-Gray, Elizabeth; Leveille, Suzanne G.; Hannan, Marian T.; Cheng, Jie; Kane, Kevin; Li, Wenjun

    2015-01-01

    Background. Regular walking is critical to maintaining health in older age. We examined influences of individual and community factors on walking habits in older adults. Methods. We analyzed walking habits among participants of a prospective cohort study of 745 community-dwelling men and women, mainly aged 70 years or older. We estimated community variations in utilitarian and recreational walking, and examined whether the variations were attributable to community differences in individual and environmental factors. Results. Prevalence of recreational walking was relatively uniform while prevalence of utilitarian walking varied across the 16 communities in the study area. Both types of walking were associated with individual health and physical abilities. However, utilitarian walking was also strongly associated with several measures of neighborhood socioeconomic status and access to amenities while recreational walking was not. Conclusions. Utilitarian walking is strongly influenced by neighborhood environment, but intrinsic factors may be more important for recreational walking. Communities with the highest overall walking prevalence were those with the most utilitarian walkers. Public health promotion of regular walking should take this into account. PMID:26339507

  6. Elephants can determine ethnicity, gender, and age from acoustic cues in human voices.

    PubMed

    McComb, Karen; Shannon, Graeme; Sayialel, Katito N; Moss, Cynthia

    2014-04-01

    Animals can accrue direct fitness benefits by accurately classifying predatory threat according to the species of predator and the magnitude of risk associated with an encounter. Human predators present a particularly interesting cognitive challenge, as it is typically the case that different human subgroups pose radically different levels of danger to animals living around them. Although a number of prey species have proved able to discriminate between certain human categories on the basis of visual and olfactory cues, vocalizations potentially provide a much richer source of information. We now use controlled playback experiments to investigate whether family groups of free-ranging African elephants (Loxodonta africana) in Amboseli National Park, Kenya can use acoustic characteristics of speech to make functionally relevant distinctions between human subcategories differing not only in ethnicity but also in sex and age. Our results demonstrate that elephants can reliably discriminate between two different ethnic groups that differ in the level of threat they represent, significantly increasing their probability of defensive bunching and investigative smelling following playbacks of Maasai voices. Moreover, these responses were specific to the sex and age of Maasai presented, with the voices of Maasai women and boys, subcategories that would generally pose little threat, significantly less likely to produce these behavioral responses. Considering the long history and often pervasive predatory threat associated with humans across the globe, it is likely that abilities to precisely identify dangerous subcategories of humans on the basis of subtle voice characteristics could have been selected for in other cognitively advanced animal species.

  7. Age determination of blood spots in forensic medicine by force spectroscopy.

    PubMed

    Strasser, Stefan; Zink, Albert; Kada, Gerald; Hinterdorfer, Peter; Peschel, Oliver; Heckl, Wolfgang M; Nerlich, Andreas G; Thalhammer, Stefan

    2007-07-20

    We present a new tool for the estimation of the age of bloodstains, which could probably be used during forensic casework. For this, we used atomic force microscopy (AFM) for high-resolution imaging of erythrocytes in a blood sample and the detection of elasticity changes on a nanometer scale. For the analytic procedure we applied a fresh blood spot on a glass slide and started the AFM detection after drying of the blood drop. In a first step, an overview image was generated showing the presence of several red blood cells, which could easily be detected due to their typical "doughnut-like" appearance. The consecutively morphological investigations in a timeframe of 4 weeks could not show any alterations. Secondly, AFM was used to test the elasticity by recording force-distance curves. The measurements were performed immediately after drying, 1.5 h, 30 h and 31 days. The conditions were kept constant at room temperature (20 degrees C) and a humidity of 30%. The obtained elasticity parameters were plotted against a timeline and repeated several times. The elasticity pattern showed a decrease over time, which are most probably influenced by the alteration of the blood spot during the drying and coagulation process. The preliminary data demonstrates the capacity of this method to use it for development of calibration curves, which can be used for estimation of bloodstain ages during forensic investigations.

  8. Reproductive and socioeconomic determinants of child survival: confounded, interactive, and age-dependent effects.

    PubMed

    Kost, K; Amin, S

    1992-01-01

    Studies of infant and child mortality have evolved to distinguish between two sets of explanatory variables-factors related to reproductive or maternal characteristics and socioeconomic factors, generally described as characteristics of the family or household. Almost all multivariate analyses include variables from each of these two sets, but there has been little consideration of the relationship between them. We examine how these two sets of variables jointly affect mortality. We test first for confounded effects by examining socioeconomic effects while excluding and then including reproductive variables in nested multivariate models. Next, we look for age-dependent effects among the explanatory variables and find that reproductive and socioeconomic factors affect mortality at differing ages of children. Finally, we examine interactive effects of the two sets of variables. We conclude that the higher mortality observed among the low status groups is not a result of greater concentration of poor reproductive patterns in those groups. Instead, higher status groups probably have more resources available for combating the negative effects of the same high-risk reproductive patterns. PMID:1514117

  9. Elephants can determine ethnicity, gender, and age from acoustic cues in human voices.

    PubMed

    McComb, Karen; Shannon, Graeme; Sayialel, Katito N; Moss, Cynthia

    2014-04-01

    Animals can accrue direct fitness benefits by accurately classifying predatory threat according to the species of predator and the magnitude of risk associated with an encounter. Human predators present a particularly interesting cognitive challenge, as it is typically the case that different human subgroups pose radically different levels of danger to animals living around them. Although a number of prey species have proved able to discriminate between certain human categories on the basis of visual and olfactory cues, vocalizations potentially provide a much richer source of information. We now use controlled playback experiments to investigate whether family groups of free-ranging African elephants (Loxodonta africana) in Amboseli National Park, Kenya can use acoustic characteristics of speech to make functionally relevant distinctions between human subcategories differing not only in ethnicity but also in sex and age. Our results demonstrate that elephants can reliably discriminate between two different ethnic groups that differ in the level of threat they represent, significantly increasing their probability of defensive bunching and investigative smelling following playbacks of Maasai voices. Moreover, these responses were specific to the sex and age of Maasai presented, with the voices of Maasai women and boys, subcategories that would generally pose little threat, significantly less likely to produce these behavioral responses. Considering the long history and often pervasive predatory threat associated with humans across the globe, it is likely that abilities to precisely identify dangerous subcategories of humans on the basis of subtle voice characteristics could have been selected for in other cognitively advanced animal species. PMID:24616492

  10. Variations in Community Prevalence and Determinants of Recreational and Utilitarian Walking in Older Age.

    PubMed

    Procter-Gray, Elizabeth; Leveille, Suzanne G; Hannan, Marian T; Cheng, Jie; Kane, Kevin; Li, Wenjun

    2015-01-01

    Background. Regular walking is critical to maintaining health in older age. We examined influences of individual and community factors on walking habits in older adults. Methods. We analyzed walking habits among participants of a prospective cohort study of 745 community-dwelling men and women, mainly aged 70 years or older. We estimated community variations in utilitarian and recreational walking, and examined whether the variations were attributable to community differences in individual and environmental factors. Results. Prevalence of recreational walking was relatively uniform while prevalence of utilitarian walking varied across the 16 communities in the study area. Both types of walking were associated with individual health and physical abilities. However, utilitarian walking was also strongly associated with several measures of neighborhood socioeconomic status and access to amenities while recreational walking was not. Conclusions. Utilitarian walking is strongly influenced by neighborhood environment, but intrinsic factors may be more important for recreational walking. Communities with the highest overall walking prevalence were those with the most utilitarian walkers. Public health promotion of regular walking should take this into account. PMID:26339507

  11. Elephants can determine ethnicity, gender, and age from acoustic cues in human voices

    PubMed Central

    McComb, Karen; Shannon, Graeme; Sayialel, Katito N.; Moss, Cynthia

    2014-01-01

    Animals can accrue direct fitness benefits by accurately classifying predatory threat according to the species of predator and the magnitude of risk associated with an encounter. Human predators present a particularly interesting cognitive challenge, as it is typically the case that different human subgroups pose radically different levels of danger to animals living around them. Although a number of prey species have proved able to discriminate between certain human categories on the basis of visual and olfactory cues, vocalizations potentially provide a much richer source of information. We now use controlled playback experiments to investigate whether family groups of free-ranging African elephants (Loxodonta africana) in Amboseli National Park, Kenya can use acoustic characteristics of speech to make functionally relevant distinctions between human subcategories differing not only in ethnicity but also in sex and age. Our results demonstrate that elephants can reliably discriminate between two different ethnic groups that differ in the level of threat they represent, significantly increasing their probability of defensive bunching and investigative smelling following playbacks of Maasai voices. Moreover, these responses were specific to the sex and age of Maasai presented, with the voices of Maasai women and boys, subcategories that would generally pose little threat, significantly less likely to produce these behavioral responses. Considering the long history and often pervasive predatory threat associated with humans across the globe, it is likely that abilities to precisely identify dangerous subcategories of humans on the basis of subtle voice characteristics could have been selected for in other cognitively advanced animal species. PMID:24616492

  12. Intellectual Disability in a Birth Cohort: Prevalence, Etiology, and Determinants at the Age of 4 Years

    PubMed Central

    Karam, Simone M.; Barros, Aluísio J.D.; Matijasevich, Alícia; dos Santos, Iná S.; Anselmi, Luciana; Barros, Fernando; Leistner-Segal, Sandra; Félix, Têmis M.; Riegel, Mariluce; Maluf, Sharbel W.; Giugliani, Roberto; Black, Maureen M.

    2016-01-01

    Background Intellectual disability (ID), characterized by impairments in intellectual function and adaptive behavior, affects 1-3% of the population. Many studies investigated its etiology, but few are cohort studies in middle-income countries. Aims To estimate prevalence, etiology, and factors related to ID among children prospectively followed since birth in a Southern Brazilian city (Pelotas). Methods In 2004, maternity hospitals were visited daily and births were identified. Live-born infants (n = 4,231) whose family lived in the urban area have been followed for several years. At the age of 2 and 4 years, performances in development and intelligence tests were evaluated using the Battelle Developmental Inventory and Wechsler Intelligence Scale, respectively. Children considered as having developmental delay were invited to attend a genetic evaluation. Results At 4 years of age, the prevalence of ID was 4.5%, and the etiology was classified into 5 groups: environmental (44.4%), genetic (20.5%), idiopathic (12.6%), neonatal sequelae (13.2%), other diseases (9.3%). Most children presented impairment in two or more areas of adaptive behavior. There was no difference in prenatal care attendance or maternal schooling among the groups. Conclusion For about 40% of children, ID was attributed to nonbiological factors, suggesting that the rate may be reduced with appropriate interventions early in life. PMID:27595410

  13. Analysis of the age of Panax ginseng based on telomere length and telomerase activity.

    PubMed

    Liang, Jiabei; Jiang, Chao; Peng, Huasheng; Shi, Qinghua; Guo, Xiang; Yuan, Yuan; Huang, Luqi

    2015-01-23

    Ginseng, which is the root of Panax ginseng (Araliaceae), has been used in Oriental medicine as a stimulant and dietary supplement for more than 7,000 years. Older ginseng plants are substantially more medically potent, but ginseng age can be simulated using unscrupulous cultivation practices. Telomeres progressively shorten with each cell division until they reach a critical length, at which point cells enter replicative senescence. However, in some cells, telomerase maintains telomere length. In this study, to determine whether telomere length reflects ginseng age and which tissue is best for such an analysis, we examined telomerase activity in the main roots, leaves, stems, secondary roots and seeds of ginseng plants of known age. Telomere length in the main root (approximately 1 cm below the rhizome) was found to be the best indicator of age. Telomeric terminal restriction fragment (TRF) lengths, which are indicators of telomere length, were determined for the main roots of plants of different ages through Southern hybridization analysis. Telomere length was shown to be positively correlated with plant age, and a simple mathematical model was formulated to describe the relationship between telomere length and age for P. ginseng.

  14. Estimating the age of Calliphora vicina eggs (Diptera: Calliphoridae): determination of embryonic morphological landmarks and preservation of egg samples.

    PubMed

    Martín-Vega, Daniel; Hall, Martin J R

    2016-05-01

    Blow fly eggs may sometimes be the only entomological evidence recovered in a forensic case, especially in cooler weather when hatching might take several days: hence, a method for estimating their age is greatly needed. However, developmental data on blow fly eggs are mainly limited to records of the time to larval hatching. The current paper describes the morphological changes occurring during embryogenesis of the blow fly Calliphora vicina Robineau-Desvoidy and their timing in relation to temperature, in order to determine those characters which can be used for simple egg age estimation using light microscopy. At 7.3 and 25 °C, 15 easily visualised morphological landmarks were determined in C. vicina living embryos, allowing for their age estimation with a resolution of 10-20% of total egg developmental time. The observed age intervals were compared to the embryonic stages described for the fruit fly Drosophila melanogaster Meigen, which are used as reference data in multiple developmental studies. Moreover, current guidelines for preservation of egg samples, which recommend the placement of living eggs directly into 80% ethanol, were tested against the hot water killing (HWK) method prior to preservation in 80% ethanol, recommended for larval and pupal specimens. Direct placement of eggs into 80% ethanol caused marked decomposition of samples, and no morphological landmarks were discernible. On the other hand, HWK fixation prior to preservation in 80% ethanol enabled visualisation of 11 of the 15 age-specific morphological landmarks that were discernible in living embryos. Therefore, HWK fixation prior to preservation in 80% ethanol is recommended for egg samples, thus unifying the protocols for collecting entomological evidence.

  15. Socialization and Self- Determination in Different-Age Dyads of Students Who Are Deafblind

    ERIC Educational Resources Information Center

    Bruce, Susan M.; Zatta, Mary C.; Gavin, Mary; Stelzer, Sharon

    2016-01-01

    Introduction: Deafblindness limits access to social cues and social feedback, thus restricting the development of social skills. Many children with CHARGE syndrome, a leading cause of deafblindness, experience challenges with emotional self-regulation and anxiety that may interfere with socialization. Learning about self-determination skills such…

  16. Determining Intensity Levels of Selected Wii Fit Activities in College Aged Individuals

    ERIC Educational Resources Information Center

    Grieser, Joshua D.; Gao, Yong; Ransdell, Lynda; Simonson, Shawn

    2012-01-01

    The purpose of this study was to determine the intensity of Nintendo Wii Fit games using indirect calorimetry. Twenty-five college students completed Wii Fit activity sessions at two difficulty levels within aerobics, strength, and yoga categories. Resting metabolic rate and exercise oxygen uptake were measured, and metabolic equivalents were…

  17. Resilience of aging populations after devastating earthquake event and its determinants - A case study of the Chi-Chi earthquake in Taiwan

    NASA Astrophysics Data System (ADS)

    Hung, Chih-Hsuan; Hung, Hung-Chih

    2016-04-01

    1.Background Major portions of urban areas in Asia are highly exposed and vulnerable to devastating earthquakes. Many studies identify ways to reduce earthquake risk by concentrating more on building resilience for the particularly vulnerable populations. By 2020, as the United Nations' warning, many Asian countries would become 'super-aged societies', such as Taiwan. However, local authorities rarely use resilience approach to frame earthquake disaster risk management and land use strategies. The empirically-based research about the resilience of aging populations has also received relatively little attention. Thus, a challenge arisen for decision-makers is how to enhance resilience of aging populations within the context of risk reduction. This study aims to improve the understanding of the resilience of aging populations and its changes over time in the aftermath of a destructive earthquake at the local level. A novel methodology is proposed to assess the resilience of aging populations and to characterize their changes of spatial distribution patterns, as well as to examine their determinants. 2.Methods and data An indicator-based assessment framework is constructed with the goal of identifying composite indicators (including before, during and after a disaster) that could serve as proxies for attributes of the resilience of aging populations. Using the recovery process of the Chi-Chi earthquake struck central Taiwan in 1999 as a case study, we applied a method combined a geographical information system (GIS)-based spatial statistics technique and cluster analysis to test the extent of which the resilience of aging populations is spatially autocorrelated throughout the central Taiwan, and to explain why clustering of resilient areas occurs in specific locations. Furthermore, to scrutinize the affecting factors of resilience, we develop an aging population resilience model (APRM) based on existing resilience theory. Using the APRM, we applied a multivariate

  18. Improving predictions of root biomechanical properties, is age a better determinant than diameter?

    NASA Astrophysics Data System (ADS)

    Loades, Kenneth; Hallett, Paul; Lynch, Jonathan; Chimungu, Joseph; Bengough, Anthony

    2014-05-01

    Roots mechanically reinforce many soils. Root tensile strength and stiffness is critical for soil stabilisation with plants potentially providing civil engineers a 'green' alternative for soil stabilisation. Relatively little is known on factors influencing root tensile strength. Through a better understanding of these factors the adoption of 'green engineering' techniques by civil engineers will improve. Existing models are limited in their accuracy due to simplistic assumptions to derive root contributions to the resistance of soil to failure. Current models typically use relationships between strength and diameter, however, there are a number of other factors potentially influencing root biomechanical properties. The effects of root age on biomechanical properties have largely been overlooked. Barley (Hordeum vulgare) was grown under differing soil conditions, waterlogged, moderate mechanical impedance and in unimpeded, control, conditions. The root system was excavated and tensile tests performed on root sections along the length of each root axis. Root tensile strength increased with increasing distance along the root axes in control soil from 0.5 MPa to 7.0 MPa at a distance of 800mm from the root tip and from 1.0 Mpa to 8.0 MPa, 500mm from the root tip when under moderate mechanical impedance. Increases in strength were also observed when plants were subjected to waterlogging with tensile strength increasing from 1.0 MPa to 3.0 MPa, 200mm from the root tip. Young's modulus increased from ~10 MPa at the root tip to ~60 MPa 400mm and 800mm from the root tip in mechanically impeded and control treatments respectively. Distance from root tip explained over 47% of the variance in root tensile strength and 34% of root stiffness. Including root diameter in the model led to further improvements in predicting root properties, explaining ~54% of root strength variance and ~49% of root stiffness. Root age has been shown to improve predictions of root tensile strength

  19. Age at first oral contraceptive use as a major determinant of vertebral bone mass in female endurance athletes.

    PubMed

    Hartard, Manfred; Kleinmond, Christine; Kirchbichler, Alexander; Jeschke, Dieter; Wiseman, Michael; Weissenbacher, Ernst Rainer; Felsenberg, Dieter; Erben, Reinhold G

    2004-10-01

    It was the aim of this retrospective analysis to examine the influence of low-dose monophasic oral contraceptives (OCs) on bone mineral density (BMD) of the femoral neck and of the spine in young female endurance athletes. Data on training intensity, dietary intake, menarche, menstrual cycle disorders, years of OC use, and age at first OC use were determined by a self-report questionnaire. Only athletes performing regular endurance exercise for more than 3 years with more than 3 h of exercise per week were included in this study and underwent a clinical assessment including measurement of weight, height, spine, and hip BMD by dual-energy X-ray absorptiometry, and collection of a blood sample. The data from 75 regularly exercising endurance athletes aged 18-35 years (26.5 +/- 4.8 years) were initially included in this analysis. Six athletes were later excluded due to oligo-/amenorrhea. Subjects were allocated into the OC group when they reported OC use for more than 3 years in women younger than 22 years of age, or when they reported OC use for more than 50% of the time after menarche in women aged 22-35 years. There were no differences in age, weight, height, body mass index (BMI), body fat, menarche, training intensity, age at start of training, or any serum parameters between OC users (n = 31) and control subjects (n = 38). However, OC users had 7.9% lower spine BMD and 8.8% lower proximal femur BMD (P < 0.01 for both sites). When the relationship between BMD of the spine and OC use was further analyzed by a stepwise model of multiple regression analysis using OC years, age at OC initiation, BMI, and menarche as independent variables, age at first OC use was found to be the best predictor of vertebral BMD, while the only significant predictor of femoral neck BMD was BMI. We conclude that OC use is associated with decreased BMD of the spine and the femoral neck in female endurance athletes, and that early age at initiation of OC use may be an important risk factor

  20. Prioritization of pesticides based on daily dietary exposure potential as determined from the SHEDS model.

    PubMed

    Melnyk, Lisa Jo; Wang, Zhaohui; Li, Zhilin; Xue, Jianping

    2016-10-01

    A major pathway for exposure to many pesticides is through diet. The objectives were to rank pesticides by comparing their calculated daily dietary exposure as determined by EPA's Stochastic Human Exposure and Dose Simulation (SHEDS) to single pesticides for different age groups to acceptable daily intakes (ADI), characterize pesticide trends in exposures over different time periods, and determine commodities contributing to pesticide exposures. SHEDS was applied, using Pesticide Data Program (PDP) (1991-2011) and pesticide usage data on crops from USDA combined with NHANES dietary consumption data, to generate exposure estimates by age group. ADI data collected from EPA, WHO, and other sources were used to rank pesticides based on relativeness of the dietary exposure potential to ADI by age groups. Sensitivity analysis provided trends in pesticide exposures. Within SHEDS, commodities contributing the majority of pesticides with greatest exposure potential were determined. The results indicated that the highest ranking pesticides were methamidophos and diazinon which exceeded 100% of the ADI. Sensitivity analysis indicated that exposure to methamidophos, diazinon, malathion, ethion and formetanate hydrochloride had a marked decrease from 1991-1999 to 2000-2011. Contributions analysis indicated that apples, mushroom, carrots, and lettuce contributed to diazinon exposure. Beans and pepper contributed to methamidophos exposure. PMID:27497764

  1. Anti-Bacterial effect of Aqueous Garlic Extract (AGE) determined by Disc Diffusion Method against Escherichia coli.

    PubMed

    Saha, S; Saha, S K; Hossain, M A; Paul, S K; Gomes, R R; Imtiaz, M; Islam, M M; Nahar, H; Begum, S A; Mirza, T T

    2016-01-01

    The study was performed to determine the antibacterial effect of aqueous extract of garlic (Allium sativum) against standard strain of Escherichia coli ATCC 25922. An interventional study was conducted in Department of Pharmacology and Therapeutics in collaboration with Department of Microbiology, Mymensingh Medical College, Mymensingh. Antibacterial effect of AGE was determined by disc diffusion method. Sensitivity of AGE determined in disc diffusion and the zone of inhibition (ZOI) was 4 mm, 10 mm and 20 mm at 25 μg/10 μl, 50 μg/10 μl and 100 μg/10 μl concentrations respectively. From the findings it is clearly determined the extract has definite antibacterial effect upon Escherichia coli. Further studies are required to detect and isolate the active ingredients present in the Garlic extract as well as detail steps of mechanism responsible for antibacterial effect. Then their effects against the studied organism should be studied in vivo separately and its toxicity profile should also be taken into account.

  2. Anti-Bacterial effect of Aqueous Garlic Extract (AGE) determined by Disc Diffusion Method against Escherichia coli.

    PubMed

    Saha, S; Saha, S K; Hossain, M A; Paul, S K; Gomes, R R; Imtiaz, M; Islam, M M; Nahar, H; Begum, S A; Mirza, T T

    2016-01-01

    The study was performed to determine the antibacterial effect of aqueous extract of garlic (Allium sativum) against standard strain of Escherichia coli ATCC 25922. An interventional study was conducted in Department of Pharmacology and Therapeutics in collaboration with Department of Microbiology, Mymensingh Medical College, Mymensingh. Antibacterial effect of AGE was determined by disc diffusion method. Sensitivity of AGE determined in disc diffusion and the zone of inhibition (ZOI) was 4 mm, 10 mm and 20 mm at 25 μg/10 μl, 50 μg/10 μl and 100 μg/10 μl concentrations respectively. From the findings it is clearly determined the extract has definite antibacterial effect upon Escherichia coli. Further studies are required to detect and isolate the active ingredients present in the Garlic extract as well as detail steps of mechanism responsible for antibacterial effect. Then their effects against the studied organism should be studied in vivo separately and its toxicity profile should also be taken into account. PMID:26931244

  3. Radiometric age determinations on Pliocene/Pleistocene formations in the lower Omo basin, Ethiopia

    USGS Publications Warehouse

    Brown, F.H.; Lajoie, K.R.

    1971-01-01

    THE potassium-argon ages presented here were obtained during 1966 to 1969 in order to provide an absolute time scale for the stratigraphic work by the international Omo Research Expedition in the Pliocene/Pleistocene formations (unpublished work of F. H. B., J. de Heinzelin and F. C. Howell) in south-west Ethiopia. Although some of these dates are not new1-3, most of the analytical procedures and data have not been presented. We also present a list of fossil localities recorded by the University of Chicago contingent of the expedition within the Shungura Formation. Preliminary descriptions of the Hominidae have been published already3,4. ?? 1971 Nature Publishing Group.

  4. Age and growth of largemouth bass in a thermally altered reservoir, as determined from otoliths

    SciTech Connect

    Perry, L.G.; Tranquilli, J.A.

    1984-01-01

    Comparative growth rates of largemouth bass (Micropterus salmoides) from heated and ambient areas of Coffeen Lake, Illinois, were estimated by back calculation of lengths at annuli using transverse sections of otoliths and by recovery of marked fish after one growing season. Calculated lengths at otolith annuli were judged to be representative of the population growth, indicating that this technique was a reliable approach to obtaining growth information on largemouth bass from thermally affected environments. Growth of the Coffeen Lake population was more rapid than most other midwest populations. Fish recaptured in heated areas generally exhibited greater annual growth increments than those recaptured in ambient areas. Young largemouth bass (ages 1-4) from heated areas had significantly greater (P < 0.05) mean lengths than those from ambient areas according to back-calculated estimates. This was attributed to a longer growing season and earlier hatching time in thermally affected areas. 33 references, 6 figures, 3 tables.

  5. Physicochemical composition of osteoporotic bone in the trichothiodystrophy premature aging mouse determined by confocal Raman microscopy.

    PubMed

    van Apeldoorn, Aart A; de Boer, Jan; van Steeg, Harry; Hoeijmakers, Jan H J; Otto, Cees; van Blitterswijk, Clemens A

    2007-01-01

    Although it has been established that premature aging trichothiodystrophy (TTD) mice display typical signs of osteoporosis, exact changes in physicochemical properties of these mice have not been elucidated. We used confocal Raman microscopy and histology to study femora of TTD mice. We measured femora isolated from xeroderma pigmentosum group A (XPA)/TTD double mutant mice to establish that Raman microscopy can be applied to measure differences in bone composition. Raman data from XPA/TTD mice showed remarkable changes in bone mineral composition. Moreover, we observed a severe form of osteoporosis, with strongly reduced cortical bone thickness. We used Raman microscopy to analyze bone composition in eight wild-type and eight TTD animals, and observed decreased levels of phosphate and carbonate in the cortex of femora isolated from TTD mice. In contrast, the bands representing the bone protein matrix were not affected in these mice.

  6. Folic acid age correlation established on folates determinations in cell homogenates.

    PubMed

    Atanasiu, V; Vătafu, A

    1994-01-01

    From the available data, there has resulted that folic acid quantity in homogenate, coming from various organs, collected from young animals is much larger than for the other age categories. These results may be correlated with intense cell proliferation and development processes that take place in the young tissues as compared to rather low values established from grown-ups and old ranges. When comparing the folates quantity found in homogenate resulting from various organs we may ascertain that, if the folates are related to grams of tissue under the test, they are more in spleen than in kidneys, liver and brains respectively. If the folates are reported to tissue protein milligrams it may be ascertained that a larger quantity of folates is found in the brains than in the other studied organs that may be due to big dilution of the proteins in the brains.

  7. Determinants of locomotor disability in people aged 55 years and over: the Rotterdam Study.

    PubMed

    Odding, E; Valkenburg, H A; Stam, H J; Hofman, A

    2001-01-01

    Locomotor disability, as defined by difficulties in activities of daily living related to lower limb function, can be the consequence of diseases and impairments of the cardiovascular, pulmonary, nervous, sensory and musculoskeletal system. We estimated the associations between specific diseases and impairments and locomotor disability, and the proportion of disability attributable to each condition, controlling for age and comorbidity. The Rotterdam Study is a prospective follow-up study among people aged 55 years and over in the general population. Locomotor disability in 1219 men and 1856 women was assessed with the Stanford Health Assessment Questionnaire. Diseases and impairments were radiological osteoarthritis, pain of the hips and knees, morning stiffness, fractures, hypertension, vascular disease, ischemic heart disease, stroke, heart failure, chronic obstructive pulmonary disease (COPD), depression, Parkinson's disease, osteoporosis, diabetes mellitus, overweight, and low vision. Adjusted odds ratios, etiologic and attributable fractions were calculated for locomotor disability. The occurrence of locomotor disability can partly be ascribed to joint pain, COPD, morning stiffness, diabetes and heart failure in both men and women. In addition in women osteoarthritis, osteoporosis, low vision, fractures, stroke and Parkinson's disease are significant etiologic fractions. In men with morning stiffness, joint pain, heart failure, diabetes mellitus, and COPD a significant proportion of their disability is attributable to this impairment. In women this was the case for Parkinson's disease, morning stiffness, low vision, heart failure, joint pain, diabetes, radiological osteoarthritis, stroke, COPD, osteoporosis, and fractures of the lower limbs, in that order. We conclude that locomotor complaints, heart failure, COPD and diabetes mellitus contribute considerably to locomotor disability in non-institutionalized elderly people. PMID:12380718

  8. Textile-based sampling for potentiometric determination of ions.

    PubMed

    Lisak, Grzegorz; Arnebrant, Thomas; Ruzgas, Tautgirdas; Bobacka, Johan

    2015-06-01

    Potentiometric sensing utilizing textile-based micro-volume sampling was applied and evaluated for the determination of clinically (Na(+), K(+), Cl(-)) and environmentally (Cd(2+), Pb(2+) and pH) relevant analytes. In this technological design, calibration solutions and samples were absorbed into textiles while the potentiometric cells (ion-selective electrodes and reference electrode) were pressed against the textile. Once the liquid, by wicking action, reached the place where the potentiometric cell was pressed onto the textile, hence closing the electric circuit, the potentiometric response was obtained. Cotton, polyamide, polyester and their blends with elastane were applied for micro-volume sampling. The textiles were found to influence the determination of pH in environmental samples with pH close to neutral and Pb(2+) at low analyte concentrations. On the other hand, textile-based micro-volume sampling was successfully applied in measurements of Na(+) using solid-contact sodium-selective electrodes utilizing all the investigated textiles for sampling. It was found that in order to extend the application of textile-based sampling toward environmental analysis of ions it will be necessary to tailor the physio-chemical properties of the textile materials. In general, textile-based sampling opens new possibilities for direct chemical analysis of small-volume samples and provide a simple and low-cost method to screen various textiles for their effects on samples to identify which textiles are the most suitable for on-body sensing.

  9. MicroRNA-Based Linkage between Aging and Cancer: from Epigenetics View Point.

    PubMed

    Saeidimehr, Saeid; Ebrahimi, Ammar; Saki, Najmaldin; Goodarzi, Parisa; Rahim, Fakher

    2016-01-01

    Ageing is a complex process and a broad spectrum of physical, psychological, and social changes over time. Accompanying diseases and disabilities, which can interfere with cancer treatment and recovery, occur in old ages. MicroRNAs (miRNAs) are a set of small non-coding RNAs, which have considerable roles in post-transcriptional regulation at gene expression level. In this review, we attempted to summarize the current knowledge of miRNAs functions in ageing, with mainly focuses on malignancies and all underlying genetic, molecular and epigenetics mechanisms. The evidences indicated the complex and dynamic nature of miRNA-based linkage of ageing and cancer at genomics and epigenomics levels which might be generally crucial for understanding the mechanisms of age-related cancer and ageing. Recently in the field of cancer and ageing, scientists claimed that uric acid can be used to regulate reactive oxygen species (ROS), leading to cancer and ageing prevention; these findings highlight the role of miRNA-based inhibition of the SLC2A9 antioxidant pathway in cancer, as a novel way to kill malignant cells, while a patient is fighting with cancer. PMID:27540517

  10. MicroRNA-Based Linkage between Aging and Cancer: from Epigenetics View Point

    PubMed Central

    Saeidimehr, Saeid; Ebrahimi, Ammar; Saki, Najmaldin; Goodarzi, Parisa; Rahim, Fakher

    2016-01-01

    Ageing is a complex process and a broad spectrum of physical, psychological, and social changes over time. Accompanying diseases and disabilities, which can interfere with cancer treatment and recovery, occur in old ages. MicroRNAs (miRNAs) are a set of small non-coding RNAs, which have considerable roles in post-transcriptional regulation at gene expression level. In this review, we attempted to summarize the current knowledge of miRNAs functions in ageing, with mainly focuses on malignancies and all underlying genetic, molecular and epigenetics mechanisms. The evidences indicated the complex and dynamic nature of miRNA-based linkage of ageing and cancer at genomics and epigenomics levels which might be generally crucial for understanding the mechanisms of age-related cancer and ageing. Recently in the field of cancer and ageing, scientists claimed that uric acid can be used to regulate reactive oxygen species (ROS), leading to cancer and ageing prevention; these findings highlight the role of miRNA-based inhibition of the SLC2A9 antioxidant pathway in cancer, as a novel way to kill malignant cells, while a patient is fighting with cancer. PMID:27540517

  11. [A comparison of skilled methods to determine gestational age in pregnancy].

    PubMed

    van Rensburg, Y Janse; Botha, D; Nel, R; Fichardt, A

    2003-05-01

    A group of 208 antenatal women at a primary health care clinic in Bloemfontein was selected for the study. Fundal height was determined by measuring the height of the fundus as well as using the uterine fundus height in relation to weeks method. The above-mentioned methods were compared with a sonar date to determine whether a specific method is more accurate in a specific stage of pregnancy. It seems as if measuring of the height of the fundus is more accurate in the second trimester. In the third trimester of pregnancy a tendency exists for both the uterine fundus height in relation to weeks method and measuring of the height of the fundus to be accurate until the 36th week of pregnancy. After the 36th week of pregnancy the uterine fundus height in relation to weeks method seems to be more accurate.

  12. Age Determination by X-ray Fluorescence Rubidium-Strontium Ratio Measurement in Lepidolite.

    PubMed

    Herzog, L F

    1960-07-29

    X-ray fluorescence analysis of several lepidolites whose rubidium and strontium concentrations had already been determined by neutron activation and stable isotope dilution, or both, indicates that this technique can be used for rapid nondestructive reconnaissance rubidiumstrontium studies, and that an x-ray analysis method comparable in accuracy to isotope dilution can probably be developed for dating Precambrian lepidolites, as the simple technique presently used has many obvious possibilities for improvement.

  13. Exploring the limitations of age-based models for health care planning.

    PubMed

    Mason, Thomas; Sutton, Matt; Whittaker, William; Birch, Stephen

    2015-05-01

    Health care decision makers are required to make planning decisions over a medium to long term planning horizon. Whilst population ageing is an important consideration for planners, age-stratified demographic models may produce misleading estimates of future resource requirements if the actual relationship between age and health is not fixed. We present a methodology which tests whether the assumption of a fixed age-health relationship is valid and estimate the magnitude of planning errors using a long time-series of measures of chronic health and service utilisation (N = 2419) taken from the Great British General Household Survey (1980-2008). We find that age-only models contain significant omitted variable bias, and that the relationship between age and health varies significantly across birth cohorts. Chronic sickness has fallen across birth cohorts born between 1890 and 2008, particularly before birth year 1930. Generational health improvements have mitigated the effects of population ageing, meaning that the population rate of sickness fell between 1980 and 2008. Planning based only on age leads to overestimation of the population level of health care need if successive cohorts are becoming healthier. Many alternative approaches exist which allow planners to relax the assumption of a fixed relationship between age and health. PMID:25780858

  14. Maintenance of age in human neurons generated by microRNA-based neuronal conversion of fibroblasts

    PubMed Central

    Huh, Christine J; Zhang, Bo; Victor, Matheus B; Dahiya, Sonika; Batista, Luis FZ; Horvath, Steve; Yoo, Andrew S

    2016-01-01

    Aging is a major risk factor in many forms of late-onset neurodegenerative disorders. The ability to recapitulate age-related characteristics of human neurons in culture will offer unprecedented opportunities to study the biological processes underlying neuronal aging. Here, we show that using a recently demonstrated microRNA-based cellular reprogramming approach, human fibroblasts from postnatal to near centenarian donors can be efficiently converted into neurons that maintain multiple age-associated signatures. Application of an epigenetic biomarker of aging (referred to as epigenetic clock) to DNA methylation data revealed that the epigenetic ages of fibroblasts were highly correlated with corresponding age estimates of reprogrammed neurons. Transcriptome and microRNA profiles reveal genes differentially expressed between young and old neurons. Further analyses of oxidative stress, DNA damage and telomere length exhibit the retention of age-associated cellular properties in converted neurons from corresponding fibroblasts. Our results collectively demonstrate the maintenance of age after neuronal conversion. DOI: http://dx.doi.org/10.7554/eLife.18648.001 PMID:27644593

  15. Effects of velocity-based resistance training on young soccer players of different ages.

    PubMed

    González-Badillo, Juan J; Pareja-Blanco, Fernando; Rodríguez-Rosell, David; Abad-Herencia, José L; Del Ojo-López, Juan J; Sánchez-Medina, Luis

    2015-05-01

    This study aimed to analyze the effect of velocity-based resistance training (RT) with moderate loads and few repetitions per set combined with jumps and sprints on physical performance in young soccer players of different ages. A total of 44 elite youth soccer players belonging to 3 teams participated in this study: an under-16 team (U16, n = 17) and an under-18 team (U18, n = 16) performed maximal velocity RT program for 26 weeks in addition to typical soccer training, whereas an under-21 team (U21, n = 11) did not perform RT. Before and after the training program, all players performed 20-m running sprint (T20), countermovement jump (CMJ), a progressive isoinertial loading test in squat to determine the load that elicited a ∼ 1 m · s(-1) velocity (V1LOAD) and an incremental field test to determine maximal aerobic speed (MAS). U16 showed significantly (p = 0.000) greater gains in V1LOAD than U18 and U21 (100/0/0%). Only U16 showed significantly (p = 0.01) greater gains than U21 (99/1/0%) in CMJ height. U18 obtained a likely better effect on CMJ performance than U21 (89/10/1%). The beneficial effects on T20 between groups were unclear. U16 showed a likely better effect on MAS than U21 (80/17/3%), whereas the rest of comparisons were unclear. The changes in CMJ correlated with the changes in T20 (r = -0.49) and V1LOAD (r = 0.40). In conclusion, velocity-based RT with moderate load and few repetitions per set seems to be an adequate method to improve physical performance in young soccer players.

  16. Video-Based Sensor for Robotic Position and Attitude determination

    NASA Technical Reports Server (NTRS)

    Howard, Richard T.; Bryan, Thomas C.; Book, Michael L.; Roe, Fred D., Jr. (Technical Monitor)

    2001-01-01

    NASA's Marshall Space Flight Center (MSFC) has, for the last ten years, developed various video-based sensors for use in automated docking systems. The latest generation of sensor will operate at rates of up to 100 Hz, determining the relative position (X, Y, and Z) and attitude (Roll, Pitch, and Yaw) between the sensor and a small 3-dimensional target, making it suitable for applications in robotic sensing. The Advanced Video Guidance Sensor (AVGS) is designed to track multiple targets at different ranges and determine the position and attitude of each one. The previous generation of video sensor, the Video Guidance Sensor (VGS), was flown twice on the Space Shuttle to test its performance on orbit. One of the tests performed was determining the relative positions and attitudes between the VGS and its target, which was moved to various positions using the Remote Manipulator System (RMS). The RMS position data and VGS measured data were analyzed after the flights, with good correlation between the position and attitude data of the two data sets. The test using the RMS gives a good idea of the ability of the use of the AVGS as a sensor for end-effector position and attitude determination.

  17. The calibration of photographic and spectroscopic films. The utilization of the digital image processor in the determination of aging of the surf clam (Spisula solidissima)

    NASA Technical Reports Server (NTRS)

    Peters, Kevin A.; Hammond, Ernest C., Jr.

    1987-01-01

    The age of the surf clam (Spisula solidissima) can be determined with the use of the Digital Image Processor. This technique is used in conjunction with a modified method for aging, refined by John Ropes of the Woods Hole Laboratory, Massachusetts. This method utilizes a thinned sectioned chondrophore of the surf clam which contains annual rings. The rings of the chondrophore are then counted to determine age. By digitizing the chondrophore, the Digital Image Processor is clearly able to separate these annual rings more accurately. This technique produces an easier and more efficient way to count annual rings to determine the age of the surf clam.

  18. Lifetime number of mates interacts with female age to determine reproductive success in female guppies.

    PubMed

    Evans, Jonathan P

    2012-01-01

    In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies.

  19. Genetic and environmental determinants of growth of school-aged children in a rural Colombian population.

    PubMed

    Mueller, W H; Titcomb, M

    1977-01-01

    Parent-offspring correlations and heritabilities of body measurements from midparent-offspring regressions are presented for school-aged children from the village of Tenza, Colombia (N = 403 families). Parent-child correlations and midparent regressions in this subsistence farming sample, are similar in magnitude to those for well nourished, urban industrial samples, suggesting that the environmental component of variability in body size is the same regardless of the environment. Tenza children are significantly shorter and lighter than upper class Bogota children, and Tenza parents have mean heights and weights similar to those of other lower class Colombian samples. Thus, chronic undernutrition has affected the growth of parents and continues to affect the growth of the present generation. Although it has been hypothesized that heritability of growth might be reduced in samples experiencing malnutrition and its sequelae, such a reduction may only be observable where environment of parents during their development is different from that of their offspring, which is not the case here. The pattern of heritabilities with respect to different body measurements in Tenza, is similar to that seen in well nourished samples, except that measurements of breadth (biacromial, bicristal, bicondylar) have heritabilities similar in magnitude to those of linear measurements (height, sitting-height, subischial length) especially in males; and heritabilities of some measurements related to adiposity are significantly higher in daughters than in sons.

  20. Lifetime number of mates interacts with female age to determine reproductive success in female guppies.

    PubMed

    Evans, Jonathan P

    2012-01-01

    In many species, mating with multiple males confers benefits to females, but these benefits may be offset by the direct and indirect costs associated with elevated mating frequency. Although mating frequency (number of mating events) is often positively associated with the degree of multiple mating (actual number of males mated), most studies have experimentally separated these effects when exploring their implications for female fitness. In this paper I describe an alternative approach using the guppy Poecilia reticulata, a livebearing freshwater fish in which females benefit directly and indirectly from mating with multiple males via consensual matings but incur direct and indirect costs of mating as a consequence of male sexual harassment. In the present study, females were experimentally assigned different numbers of mates throughout their lives in order to explore how elevated mating frequency and multiple mating combine to influence lifetime reproductive success (LRS) and survival (i.e. direct components of female fitness). Under this mating design, survival and LRS were not significantly affected by mating treatment, but there was a significant interaction between brood size and reproductive cycle (a correlate of female age) because females assigned to the high mating treatment produced significantly fewer offspring later in life compared to their low-mating counterparts. This negative effect of mating treatment later in life may be important in these relatively long-lived fishes, and this effect may be further exacerbated by the known cross-generational fitness costs of sexual harassment in guppies. PMID:23071816

  1. Body size variation of four latitudinally-separated populations of a toad species: age and growth rate as the proximate determinants.

    PubMed

    Yu, Tonglei; Lu, Xin

    2013-09-01

    Age and growth rate are critical parameters determining the body size of adult anurans, which grow indeterminately. Therefore, evaluating their relative importance and selective pressures acting on them may help to explain variation in body size of anurans across geographical populations. Based on the data on body size and skeletochronological age of 4 Asiatic toad (Bufo gargarizans) populations that are widely separated in latitude, the present study showed that toads at the northern extremity of the range were the oldest, on average, and grew relatively fast, toads at the southern end of the range were relatively old but grew fastest, whereas mid-latitude toads were intermediate in both traits. These results indicated that relative contributions of age and growth rate to body size differed among populations. From a life history perspective, greater age attained by toads at higher latitudes should result from delayed maturation, and faster growth from an adaptive response to strong seasonal time constraints; in contrast, selective pressures on the 2 parameters at lower latitudes might be associated, respectively, with low adult death rates and longer favorable growing seasons.

  2. The development of a colorimetric scale as a visual aid for the bruise age determination of bite marks and blunt trauma.

    PubMed

    Nuzzolese, E; Di Vella, G

    2012-12-01

    Medical examiners and forensic odontologists are frequently asked to establish the age of a bruise or bitemark on either a living and deceased subjects. The age of bruising has an important medico-legal significance and may be relevant in the investigations related to such crimes as child abuse, domestic violence and homicide. A colorimetric scale for forensic photography based on the colors of the bruise itself, has never been proposed due to the fact that photographic reproduction of color is unreliable and depends on several factors; the camera used, lighting, printer and photo-editing color calibration. The authors propose two colorimetric scales, both with and without linear measurements, and with 90° angulations, six bruise colors, and three circles with black and white calibrators, which are to be used for the forensic photography of injuries involving the epidermis of Caucasian subjects. The two scales could also be employed on living subjects during different stages of the healing process, or on cadavers in order to provide evidential documentation, image verification and analysis. Such an aid would provide a reliable standard condition and allow for color calibration. The colors represented on the scales would be an aid for the interpretation and objectivity required in estimating the age of the bruise, particularly when the analysis is made directly onto computer images prior to printing. The proposed colorimetric scales do not attempt to give a definitive account of the diverse scientific methods available for the assessment of the age of bruising. The observation of a large sample of blunt trauma and bite mark injuries employing the proposed colorimetric scales would be needed in order to verify and validate the use of these scales. It should be borne in mind that bruise age estimation requires an expert opinion with several degrees of accuracy and variability involved. The age of a bruise cannot be determined by color alone. PMID:23474503

  3. Determinants of Short Interbirth Interval among Reproductive Age Mothers in Arba Minch District, Ethiopia.

    PubMed

    Hailu, Desta; Gulte, Teklemariam

    2016-01-01

    Background. One of the key strategies to reduce fertility and promote the health status of mothers and their children is adhering to optimal birth spacing. However, women still have shorter birth intervals and studies addressing their determinants were scarce. The objective of this study, therefore, was to assess determinants of birth interval among women who had at least two consecutive live births. Methods. Case control study was conducted from February to April 2014. Cases were women with short birth intervals (<3 years), whereas controls were women having history of optimal birth intervals (3 to 5 years). Bivariate and multivariable analyses were performed. Result. Having no formal education (AOR = 2.36, 95% CL: [1.23-4.52]), duration of breast feeding for less than 24 months (AOR: 66.03, 95% CI; [34.60-126]), preceding child being female (AOR: 5.73, 95% CI; [3.18-10.310]), modern contraceptive use (AOR: 2.79, 95% CI: [1.58-4.940]), and poor wealth index (AOR: 4.89, 95% CI; [1.81-13.25]) of respondents were independent predictors of short birth interval. Conclusion. In equalities in education, duration of breast feeding, sex of the preceding child, contraceptive method use, and wealth index were markers of unequal distribution of inter birth intervals. Thus, to optimize birth spacing, strategies of providing information, education and communication targeting predictor variables should be improved. PMID:27239553

  4. Determinants of Short Interbirth Interval among Reproductive Age Mothers in Arba Minch District, Ethiopia

    PubMed Central

    Hailu, Desta; Gulte, Teklemariam

    2016-01-01

    Background. One of the key strategies to reduce fertility and promote the health status of mothers and their children is adhering to optimal birth spacing. However, women still have shorter birth intervals and studies addressing their determinants were scarce. The objective of this study, therefore, was to assess determinants of birth interval among women who had at least two consecutive live births. Methods. Case control study was conducted from February to April 2014. Cases were women with short birth intervals (<3 years), whereas controls were women having history of optimal birth intervals (3 to 5 years). Bivariate and multivariable analyses were performed. Result. Having no formal education (AOR = 2.36, 95% CL: [1.23–4.52]), duration of breast feeding for less than 24 months (AOR: 66.03, 95% CI; [34.60–126]), preceding child being female (AOR: 5.73, 95% CI; [3.18–10.310]), modern contraceptive use (AOR: 2.79, 95% CI: [1.58–4.940]), and poor wealth index (AOR: 4.89, 95% CI; [1.81–13.25]) of respondents were independent predictors of short birth interval. Conclusion. In equalities in education, duration of breast feeding, sex of the preceding child, contraceptive method use, and wealth index were markers of unequal distribution of inter birth intervals. Thus, to optimize birth spacing, strategies of providing information, education and communication targeting predictor variables should be improved. PMID:27239553

  5. College-Based Inclusion Programming for Transition-Age Students with Autism

    ERIC Educational Resources Information Center

    Zager, Dianne; Alpern, Carol S.

    2010-01-01

    Considerations for college-based programming for transition-age students with autism spectrum disorders (ASD) are addressed in this article, with particular attention to social communication supports necessary to facilitate student success. An overview of current literature related to college-based programming and support for students with ASD in…

  6. Age of Eocene/Oligocene boundary based on extrapolation from North American microtektite layer

    SciTech Connect

    Glass, B.P.; Crosbie, J.R.

    1982-04-01

    Microtektites believed to belong to the North American tektite strewn field have been found in upper Eocene sediments in cores from nine Deep Sea Drilling Project sites in the Caribbean Sea, Gulf of Mexico, equatorial Pacific, and eastern equatorial Indian Ocean. The microtektite layer has an age of 34.2 +- 0.6 m.y. based on fission-track dating of the microtektites and K-Ar and fission-track dating of the North American tektites. Extrapolation from the microtektite layer to the overlying Eocene/Oligocene boundary indicates an age of 32.3 +- 0.9 m.y. for the Eocene/Oligocene boundary as defined at each site in the Initial Reports of the Deep Sea Drilling Project. This age is approximately 5 m.y. younger than the age of 37.5 m.y. that is generally assigned to the boundary based on recently published Cenozoic time scales. 3 figures, 5 tables.

  7. Age Determination of the Remaining Peat in the Sacramento-San Joaquin Delta, California, USA

    USGS Publications Warehouse

    Drexler, Judith Z.; de Fontaine, Christian S.; Knifong, Donna L.

    2007-01-01

    Introduction The Sacramento-San Joaquin Delta of California was once a 1,400 square kilometer (km2) tidal marsh, which contained a vast layer of peat ranging up to 15 meters (m) thick (Atwater and Belknap, 1980). Because of its favorable climate and highly fertile peat soils, the majority of the Delta was drained and reclaimed for agriculture during the late 1800s and early 1900s. Drainage of the peat soils changed the conditions in the surface layers of peat from anaerobic (having no free oxygen present) to aerobic (exposed to the atmosphere). This change in conditions greatly increased the decomposition rate of the peat, which consists largely of organic (plant) matter. Thus began the process of land-surface subsidence, which initially was a result of peat shrinkage and compaction, and later largely was a result of oxidation by which organic carbon in the peat essentially vaporized to carbon dioxide (Deverel and others, 1998; Ingebritsen and Ikehara, 1999). Because of subsidence, the land-surface elevation on farmed islands in the Delta has decreased from a few meters to as much as 8 m below local mean sea level (California Department of Water Resources, 1995; Steve Deverel, Hydrofocus, Inc., written commun., 2007). The USGS, in collaboration with the University of California at Davis, and Hydrofocus Inc. of Davis, California, has been studying the formation of the Delta and the impact of wetland reclamation on the peat column as part of a project called Rates and Evolution of Peat Accretion through Time (REPEAT). The purpose of this report is to provide results on the age of the remaining peat soils on four farmed islands in the Delta.

  8. A review of Model Production Function age determinations on the Mercury surface

    NASA Astrophysics Data System (ADS)

    Massironi, Matteo; Cremonese, Gabriele; Marchi, Simone; Martellato, Elena; Giacomini, Lorenza; Ferrari, Sabrina

    The Model Production Function (MPF) chronology relies on the estimate of the crater size-frequency distribution for a specific planet on the basis of theoretical prediction of the impactor flux (Marchi et al., 2009). Hence it is a readily and flexible method to infer ages on any planets also considering a variable impact flux through time. In addition the methodology derive crater size distribution function from the distribution of impactors applying only once the Holsapple and Housen (2007) scaling law; this allows a consistent control of the function itself and an improved fit of the crater statistics, which, on its own, may give even some insights for the uppermost layering and rheology of the investigated crusts (Massironi et al. 2009). During the here proposed presentation, we will discuss all the applications of MPF method realized on the hermean surface so far. This will give us the opportunity to explain the importance of the geological interpretation required to correctly apply this methodology as well as to illustrate strength and weakness of such an approach. References Holsapple, K. A., and Housen K. R. (2007). A crater and its ejecta: An interpreta-tion of Deep Impact, ICARUS, 187, 345 -356. Marchi S, Mottola S, Cremonese G, Massironi M., Martellato E (2009). A New Chronology for the Moon and Mercury. THE ASTRONOM-ICAL JOURNAL, vol. 137; p. 4936-4948. Massironi M., Cremonese G, Marchi S, Martellato E, Mottola S, Wagner RJ (2009). Mercury's geochronology revised by applying Model Pro-duction Function to Mariner 10 data: Geological implications. GEOPHYSICAL RESEARCH LETTERS, vol. 36; L21204.

  9. Social and health behavioural determinants of maternal child-feeding patterns in preschool-aged children.

    PubMed

    Moreira, Isabel; Severo, Milton; Oliveira, Andreia; Durão, Catarina; Moreira, Pedro; Barros, Henrique; Lopes, Carla

    2016-04-01

    Parental child-feeding attitudes and practices may compromise the development of healthy eating habits and adequate weight status in children. This study aimed to identify maternal child-feeding patterns in preschool-aged children and to evaluate their association with maternal social and health behavioural characteristics. Trained interviewers evaluated 4724 dyads of mothers and their 4-5-year-old child from the Generation XXI cohort. Maternal child-feeding attitudes and practices were assessed through the Child Feeding Questionnaire and the Overt/Covert Control scale. Associations were estimated using linear regression [adjusted for maternal education, body mass index (BMI), fruit and vegetables (F&V) intake and child's BMI z-score]. Principal component analysis defined a three-factor structure explaining 58% of the total variance of maternal child-feeding patterns: perceived monitoring - representing mothers with higher levels of monitoring, perceived responsibility and overt control; restriction - characterizing mothers with higher covert control, restriction and concerns about child's weight; pressure to eat - identifying mothers with higher levels of pressure to eat and overt control. Lower socioeconomic status, better health perception, higher F&V intake and offspring cohabitation were associated with more 'perceived monitoring' mothers. Higher maternal F&V intake and depression were associated with more 'restrictive' mothers. Younger mothers, less educated, with poorer health perception and offspring cohabiting, were associated with higher use of 'pressure to eat'. Maternal socioeconomic indicators and family environment were more associated with perceived monitoring and pressure to eat, whereas maternal health behavioural characteristics were mainly associated with restriction. These findings will be helpful in future research and public health programmes on child-feeding patterns.

  10. Aging-related elevation of sphingoid bases shortens yeast chronological life span by compromising mitochondrial function

    PubMed Central

    Yi, Jae Kyo; Xu, Ruijuan; Jeong, Eunmi; Mileva, Izolda; Truman, Jean-Philip; Lin, Chih-li; Wang, Kai; Snider, Justin; Wen, Sally; Obeid, Lina M.; Hannun, Yusuf A.; Mao, Cungui

    2016-01-01

    Sphingoid bases (SBs) as bioactive sphingolipids, have been implicated in aging in yeast. However, we know neither how SBs are regulated during yeast aging nor how they, in turn, regulate it. Herein, we demonstrate that the yeast alkaline ceramidases (YPC1 and YDC1) and SB kinases (LCB4 and LCB5) cooperate in regulating SBs during the aging process and that SBs shortens chronological life span (CLS) by compromising mitochondrial functions. With a lipidomics approach, we found that SBs were increased in a time-dependent manner during yeast aging. We also demonstrated that among the enzymes known for being responsible for the metabolism of SBs, YPC1 was upregulated whereas LCB4/5 were downregulated in the course of aging. This inverse regulation of YPC1 and LCB4/5 led to the aging-related upregulation of SBs in yeast and a reduction in CLS. With the proteomics-based approach (SILAC), we revealed that increased SBs altered the levels of proteins related to mitochondria. Further mechanistic studies demonstrated that increased SBs inhibited mitochondrial fusion and caused fragmentation, resulting in decreases in mtDNA copy numbers, ATP levels, mitochondrial membrane potentials, and oxygen consumption. Taken together, these results suggest that increased SBs mediate the aging process by impairing mitochondrial structural integrity and functions. PMID:27008706

  11. BUILDING REALISTIC BIOLOGICALLY-BASED PHARMACOKINETIC MODELS FOR PREDICTING SUSCEPTIBILITY IN THE AGED POPULATIONS

    EPA Science Inventory

    Detoxification and elimination of xenobiotics is a major function of the liver and is important in maintaining the metabolic homeostasis of the organism. The degree to which aging affects hepatic metabolism is not known. The expression of XMEs, in part, determines the fate of the...

  12. Determinants of nonimmunization of children under 5 years of age in Pakistan

    PubMed Central

    Murtaza, Fowad; Mustafa, Tajammal; Awan, Rabia

    2016-01-01

    Background: Child vaccination is perhaps the first line of defense to ensure a healthy society. Unfortunately, the coverage of child vaccination in Pakistan is poor resulting in unnecessary yet preventable deaths. This study investigated the determinants and reasons for not vaccinating children in Pakistan. Materials and Methods: The study used the Pakistan Integrated Household Survey/Household Integrated Economic Survey 2001–2002 data. Demographic, distance to health facility, poverty status, literacy and education, and location of residence were used as determinants of nonimmunization of children. Descriptive statistics including frequency distribution, proportions for categorical variables and mean for continuous variables, and logistic regression analysis were done using the Stata 11.0. Results: Almost 7.73% children in Pakistan were never immunized. More than 87.4% of these lived in the rural areas. Prevalence of nonimmunization was highest in Balochistan compared to other provinces. Large households appeared to have increased risk of a child not being vaccinated. Moreover, low literacy and education of the head of the household and the spouse was also associated with low vaccination coverage. Distance from the health facility was found to be another factor related to nonimmunization of children. Increase in per capita income significantly decreased the risk of missing vaccinations. Conclusions: Prevention and immunization programs should focus more on high-risk regions such as Balochistan and rural areas. Literacy, education, and economic status were among the other significant factors associated with low vaccination rates, which need a special focus in the public policy to achieve the target of a healthy society. PMID:26929727

  13. Age determines the effects of blood pressure lowering during the acute phase of ischemic stroke: the TICA study.

    PubMed

    Leira, Rogelio; Millán, Mónica; Díez-Tejedor, Exuperio; Blanco, Miguel; Serena, Joaquín; Fuentes, Blanca; Rodríguez-Yáñez, Manuel; Castellanos, Mar; Lago, Aida; Dávalos, Antonio; Castillo, José

    2009-10-01

    To increase understanding of the influence of blood pressure (BP) changes on functional outcome, we designed a multicenter, prospective, observational study involving patients with ischemic stroke. We included 1092 patients with ischemic stroke. BP was measured on admission and after 8, 16, 24, 32, 40, and 48 hours, and the averages of the readings were taken every 8 hours on days 3 to 7, at the day of discharge, and at 3 months. The main study variable was modified Rankin scale at 3 months. Systolic BPs >181 mm Hg at the emergency department and after 24 hours were associated with poor prognosis (odds ratio [OR]: 2.2, 95% CI: 1.2 to 4.2 and OR: 1.3, 95% CI: 1.1 to 2.3, respectively); systolic BP <136 mm Hg at the emergency department also determined worse prognosis at 3 months (OR: 1.3; 95% CI: 1.1 to 2.9). The influence of systolic BP changes in the first hours depended on patient age. In elder patients (>70 years), reductions in systolic BP determined a significant increase in the proportion of patients with worse prognosis. In patients >80 years of age, decreases in systolic BP >27.2 mm Hg determined a worse prognosis in patients with antihypertensive treatment at the emergency department (n=91) compared with those who did not receive treatment (n=106; OR: 21.7, 95% CI: 13.6 to 33.5 versus OR: 8.5, 95% CI: 3.2 to 19.6). In summary, the effect of BP modification during the acute phase of ischemic stroke on functional outcome is strongly dependent on age.

  14. Human iPSC-based Modeling of Late-Onset Disease via Progerin-induced Aging

    PubMed Central

    Miller, Justine D.; Ganat, Yosif M.; Kishinevsky, Sarah; Bowman, Robert L.; Liu, Becky; Tu, Edmund Y.; Mandal, Pankaj; Vera, Elsa; Shim, Jae-won; Kriks, Sonja; Taldone, Tony; Fusaki, Noemi; Tomishima, Mark J.; Krainc, Dimitri; Milner, Teresa A.; Rossi, Derrick J.; Studer, Lorenz

    2014-01-01

    Summary Reprogramming somatic cells to induced pluripotent stem cells (iPSCs), resets their identity back to an embryonic age, and thus presents a significant hurdle for modeling late-onset disorders. In this study, we describe a strategy for inducing aging-related features in human iPSC-derived lineages and apply it to the modeling of Parkinson’s disease (PD). Our approach involves expression of progerin, a truncated form of lamin A associated with premature aging. We found that expression of progerin in iPSC-derived fibroblasts and neurons induces multiple aging-related markers and characteristics, including dopamine-specific phenotypes such as neuromelanin accumulation. Induced aging in PD-iPSC-derived dopamine neurons revealed disease phenotypes that require both aging and genetic susceptibility, such as pronounced dendrite degeneration, progressive loss of tyrosine-hydroxylase (TH) expression and enlarged mitochondria or Lewy body-precursor inclusions. Thus, our study suggests that progerin-induced aging can be used to reveal late-onset age-related disease features in hiPSC-based disease models. PMID:24315443

  15. Satisfaction with web-based training in an integrated healthcare delivery network: do age, education, computer skills and attitudes matter?

    PubMed Central

    Atreja, Ashish; Mehta, Neil B; Jain, Anil K; Harris, CM; Ishwaran, Hemant; Avital, Michel; Fishleder, Andrew J

    2008-01-01

    Background Healthcare institutions spend enormous time and effort to train their workforce. Web-based training can potentially streamline this process. However the deployment of web-based training in a large-scale setting with a diverse healthcare workforce has not been evaluated. The aim of this study was to evaluate the satisfaction of healthcare professionals with web-based training and to determine the predictors of such satisfaction including age, education status and computer proficiency. Methods Observational, cross-sectional survey of healthcare professionals from six hospital systems in an integrated delivery network. We measured overall satisfaction to web-based training and response to survey items measuring Website Usability, Course Usefulness, Instructional Design Effectiveness, Computer Proficiency and Self-learning Attitude. Results A total of 17,891 healthcare professionals completed the web-based training on HIPAA Privacy Rule; and of these, 13,537 completed the survey (response rate 75.6%). Overall course satisfaction was good (median, 4; scale, 1 to 5) with more than 75% of the respondents satisfied with the training (rating 4 or 5) and 65% preferring web-based training over traditional instructor-led training (rating 4 or 5). Multivariable ordinal regression revealed 3 key predictors of satisfaction with web-based training: Instructional Design Effectiveness, Website Usability and Course Usefulness. Demographic predictors such as gender, age and education did not have an effect on satisfaction. Conclusion The study shows that web-based training when tailored to learners' background, is perceived as a satisfactory mode of learning by an interdisciplinary group of healthcare professionals, irrespective of age, education level or prior computer experience. Future studies should aim to measure the long-term outcomes of web-based training. PMID:18922178

  16. Color difference threshold determination for acrylic denture base resins.

    PubMed

    Ren, Jiabao; Lin, Hong; Huang, Qingmei; Liang, Qifan; Zheng, Gang

    2015-01-01

    This study aimed to set evaluation indicators, i.e., perceptibility and acceptability color difference thresholds, of color stability for acrylic denture base resins for a spectrophotometric assessing method, which offered an alternative to the visual method described in ISO 20795-1:2013. A total of 291 disk specimens 50±1 mm in diameter and 0.5±0.1 mm thick were prepared (ISO 20795-1:2013) and processed through radiation tests in an accelerated aging chamber (ISO 7491:2000) for increasing times of 0 to 42 hours. Color alterations were measured with a spectrophotometer and evaluated using the CIE L*a*b* colorimetric system. Color differences were calculated through the CIEDE2000 color difference formula. Thirty-two dental professionals without color vision deficiencies completed perceptibility and acceptability assessments under controlled conditions in vitro. An S-curve fitting procedure was used to analyze the 50:50% perceptibility and acceptability thresholds. Furthermore, perceptibility and acceptability against the differences of the three color attributes, lightness, chroma, and hue, were also investigated. According to the S-curve fitting procedure, the 50:50% perceptibility threshold was 1.71ΔE00 (r(2)=0.88) and the 50:50% acceptability threshold was 4.00 ΔE00 (r(2)=0.89). Within the limitations of this study, 1.71/4.00 ΔE00 could be used as perceptibility/acceptability thresholds for acrylic denture base resins.

  17. Dependency of magnetocardiographically determined fetal cardiac time intervals on gestational age, gender and postnatal biometrics in healthy pregnancies

    PubMed Central

    van Leeuwen, Peter; Lange, Silke; Klein, Anita; Geue, Daniel; Grönemeyer, Dietrich HW

    2004-01-01

    Background Magnetocardiography enables the precise determination of fetal cardiac time intervals (CTI) as early as the second trimester of pregnancy. It has been shown that fetal CTI change in course of gestation. The aim of this work was to investigate the dependency of fetal CTI on gestational age, gender and postnatal biometric data in a substantial sample of subjects during normal pregnancy. Methods A total of 230 fetal magnetocardiograms were obtained in 47 healthy fetuses between the 15th and 42nd week of gestation. In each recording, after subtraction of the maternal cardiac artifact and the identification of fetal beats, fetal PQRST courses were signal averaged. On the basis of therein detected wave onsets and ends, the following CTI were determined: P wave, PR interval, PQ interval, QRS complex, ST segment, T wave, QT and QTc interval. Using regression analysis, the dependency of the CTI were examined with respect to gestational age, gender and postnatal biometric data. Results Atrioventricular conduction and ventricular depolarization times could be determined dependably whereas the T wave was often difficult to detect. Linear and nonlinear regression analysis established strong dependency on age for the P wave and QRS complex (r2 = 0.67, p < 0.001 and r2 = 0.66, p < 0.001) as well as an identifiable trend for the PR and PQ intervals (r2 = 0.21, p < 0.001 and r2 = 0.13, p < 0.001). Gender differences were found only for the QRS complex from the 31st week onward (p < 0.05). The influence on the P wave or QRS complex of biometric data, collected in a subgroup in whom recordings were available within 1 week of birth, did not display statistical significance. Conclusion We conclude that 1) from approximately the 18th week to term, fetal CTI which quantify depolarization times can be reliably determined using magnetocardiography, 2) the P wave and QRS complex duration show a high dependency on age which to a large part reflects fetal growth and 3) fetal gender

  18. Dental age estimation in Malay children based on all permanent teeth types.

    PubMed

    Yusof, M Y P M; Thevissen, P W; Fieuws, S; Willems, G

    2014-03-01

    The applicability of the Willems et al. model was verified on a collected sample of Malay (Malaysian nationality) children. This sample was split in a reference sample to develop a Malay-specific prediction model based on the Willems et al. method and in a test sample to validate this new developed model. Next, the incorporation of third molars into this model was analyzed. Panoramic radiographs (n = 1,403) of Malay children aged between 4 and 14.99 years (n = 702) and subadults aged between 15 and 23.99 years (n = 701) were collected. The left mandibular seven permanent teeth of the children were scored based on the staging technique described by Demirjian and converted to age using the Willems et al. method. Third molar development of all individuals was staged based on the technique described by Gleiser and Hunt modified by Kohler. Differences between dental age and chronological age were calculated and expressed in mean error (ME), mean absolute error (MAE), and root mean square error (RMSE). The Willems et al. model verified on the collected Malay children overestimated chronological age with a ME around 0.45 year. Small differences in ME, MAE, and RMSE between the verified Malay-specific prediction model and the Willems et al. model were observed. An overall neglected decrease in RMSE was detected adding third molar stages to the developed permanent teeth model.

  19. Crustal subsidence rate off Hawaii determined from sup 234 U/ sup 238 U ages of drowned coral reefs

    SciTech Connect

    Ludwig, K.R.; Szabo, B.J.; Simmons, K.R. ); Moore, J.G. )

    1991-02-01

    A series of submerged coral reefs off northwestern Hawaii was formed during (largely glacial) intervals when the rate of local sea-level rise was less than the maximum upward growth rate of the reefs. Mass-spectrometric {sup 234}U/{sup 238}U ages for samples from six such reefs range from 17 to 475 ka and indicate that this part of the Hawaiian Ridge has been subsiding at a roughly uniform rate of 2.6 mm/yr for the past 475 ka. The {sup 234}U/{sup 238}U ages are in general agreement with model ages of reef drowning (based on estimates of paleo-sea-level stands derived from oxygen-isotope ratios of deep-sea sediments), but there are disagreements in detail. The high attainable precision ({plus minus}10 ka or better on samples younger than {approximately}800 ka), large applicable age range, relative robustness against open-system behavior, and ease of analysis for this technique hold great promise for future applications of dating of 50-1,000 ka coral.

  20. Feasibility of a Home-Based Speed of Processing Training Program in Middle-Aged and Older Adults With HIV.

    PubMed

    Cody, Shameka L; Fazeli, Pariya L; Vance, David E

    2015-08-01

    There has been much optimism over the positive impact of combination antiretroviral therapy (cART) on life expectancy for people with HIV; however, those aging with HIV fear potential day-to-day challenges associated with the development of cognitive deficits. The presence of cognitive deficits has generated major safety concerns because it has been shown to impact driving, mobility, and employment. Given the efficacy of a computerized speed of processing training program administered in the laboratory to older adults and adults with HIV, this study was designed to determine the feasibility of using a home-based speed of processing training program to improve cognitive function in middle-aged and older adults with HIV. In this within-subject pre-post experimental design, 20 middle-aged and older adults (i.e., age of 40+ years) with HIV were administered a brief neuropsychological assessment to gauge their baseline cognitive function before participating in a 10-hour home-based computerized cognitive remediation training program. In addition to self-reported cognitive gains, a 6-week posttest indicated significant improvements on the Useful Field of View, a measure of speed of processing and possible transfer to the Timed Instrumental Activities of Daily Living test, a measure of everyday functioning. These findings show that speed of processing training can successfully improve cognitive function in this vulnerable population even when administered in remote settings such as the privacy of one's home.

  1. Residual stress determination from a laser-based curvature measurement

    SciTech Connect

    W. D. Swank; R. A. Gavalya; J. K. Wright; R. N. Wright

    2000-05-08

    Thermally sprayed coating characteristics and mechanical properties are in part a result of the residual stress developed during the fabrication process. The total stress state in a coating/substrate is comprised of the quench stress and the coefficient of thermal expansion (CTE) mismatch stress. The quench stress is developed when molten particles impact the substrate and rapidly cool and solidify. The CTE mismatch stress results from a large difference in the thermal expansion coefficients of the coating and substrate material. It comes into effect when the substrate/coating combination cools from the equilibrated deposit temperature to room temperature. This paper describes a laser-based technique for measuring the curvature of a coated substrate and the analysis required to determine residual stress from curvature measurements. Quench stresses were determined by heating the specimen back to the deposit temperature thus removing the CTE mismatch stress. By subtracting the quench stress from the total residual stress at room temperature, the CTE mismatch stress was estimated. Residual stress measurements for thick (>1mm) spinel coatings with a Ni-Al bond coat on 304 stainless steel substrates were made. It was determined that a significant portion of the residual stress results from the quenching stress of the bond coat and that the spinel coating produces a larger CTE mismatch stress than quench stress.

  2. Residual Stress Determination from a Laser-Based Curvature Measurement

    SciTech Connect

    Swank, William David; Gavalya, Rick Allen; Wright, Julie Knibloe; Wright, Richard Neil

    2000-05-01

    Thermally sprayed coating characteristics and mechanical properties are in part a result of the residual stress developed during the fabrication process. The total stress state in a coating/substrate is comprised of the quench stress and the coefficient of thermal expansion (CTE) mismatch stress. The quench stress is developed when molten particles impact the substrate and rapidly cool and solidify. The CTE mismatch stress results from a large difference in the thermal expansion coefficients of the coating and substrate material. It comes into effect when the substrate/coating combination cools from the equilibrated deposit temperature to room temperature. This paper describes a laser-based technique for measuring the curvature of a coated substrate and the analysis required to determine residual stress from curvature measurements. Quench stresses were determined by heating the specimen back to the deposit temperature thus removing the CTE mismatch stress. By subtracting the quench stress from the total residual stress at room temperature, the CTE mismatch stress was estimated. Residual stress measurements for thick (>1mm) spinel coatings with a Ni-Al bond coat on 304 stainless steel substrates were made. It was determined that a significant portion of the residual stress results from the quenching stress of the bond coat and that the spinel coating produces a larger CTE mismatch stress than quench stress.

  3. Determinants of undernutrition in children under 2 years of age from rural Bangladesh.

    PubMed

    Ahmed, A M Shamsir; Ahmed, Tahmeed; Roy, S K; Alam, Nurul; Hossain, Md Iqbal

    2012-10-01

    This study aimed to assess the determinants of under nutrition among under-two year old children of rural Bangladesh. The data of the National Nutrition Program baseline survey conducted in 2004 was analyzed, which included 8,885 under-two children and their mothers. Among the children studied, 41%, 35% and 18% were stunted, underweight, and wasted; and 16%, 11.5% and 3% were severely-stunted, underweight, and wasted, respectively. Multivariate analysis revealed that undernourished children were less likely to be female and having received measles vaccination, more likely to have suffered from diarrhea in the previous two weeks, and more likely to have older (>30 years), shorter (<145 cm), undernourished (BMI <18.5 kg/m²) and illiterate/less educated mother. Children with moderate stunting and underweight were more likely to reside in households with unhygienic toilet. Children with all forms of under nutrition were more often from families with lowest quintile of asset index. The identified associated/risk factors can be used for designing and targeting preventive programs for undernutrition. PMID:22728631

  4. Human locomotion on snow: determinants of economy and speed of skiing across the ages

    PubMed Central

    Formenti, Federico; Ardigò, Luca P; Minetti, Alberto E

    2005-01-01

    We explore here the evolution of skiing locomotion in the last few thousand years by investigating how humans adapted to move effectively in lands where a cover of snow, for several months every year, prevented them from travelling as on dry ground. Following historical research, we identified the sets of skis corresponding to the ‘milestones’ of skiing evolution in terms of ingenuity and technology, built replicas of them and measured the metabolic energy associated to their use in a climate-controlled ski tunnel. Six sets of skis were tested, covering a span from 542 AD to date. Our results show that: (i) the history of skiing is associated with a progressive decrease in the metabolic cost of transport, (ii) it is possible today to travel at twice the speed of ancient times using the same amount of metabolic power and (iii) the cost of transport is speed-independent for each ski model, as during running. By combining this finding with the relationship between time of exhaustion and the sustainable fraction of metabolic power, a prediction of the maximum skiing speed according to the distance travelled is provided for all past epochs, including two legendary historical journeys (1206 and 1520 AD) on snow. Our research shows that the performances in races originating from them (Birkebeiner and Vasaloppet) and those of other modern competitions (skating versus classical techniques) are well predicted by the evolution of skiing economy. Mechanical determinants of the measured progression in economy are also discussed in the paper. PMID:16048771

  5. Genetic Determinants of Age-Related Macular Degeneration in Diverse Populations From the PAGE Study

    PubMed Central

    Restrepo, Nicole A.; Spencer, Kylee L.; Goodloe, Robert; Garrett, Tiana A.; Heiss, Gerardo; Bůžková, Petra; Jorgensen, Neal; Jensen, Richard A.; Matise, Tara C.; Hindorff, Lucia A.; Klein, Barbara E. K.; Klein, Ronald; Wong, Tien Y.; Cheng, Ching-Yu; Cornes, Belinda K.; Tai, E.-Shyong; Ritchie, Marylyn D.; Haines, Jonathan L.; Crawford, Dana C.

    2014-01-01

    Purpose. Substantial progress has been made in identifying susceptibility variants for AMD in European populations; however, few studies have been conducted to understand the role these variants play in AMD risk in diverse populations. The present study aims to examine AMD risk across diverse populations in known and suspected AMD complement factor and lipid-related loci. Methods. Targeted genotyping was performed across study sites for AMD and lipid trait-associated single nucleotide polymorphism (SNPs). Genetic association tests were performed at individual sites and then meta-analyzed using logistic regression assuming an additive genetic model stratified by self-described race/ethnicity. Participants included cases with early or late AMD and controls with no signs of AMD as determined by fundus photography. Populations included in this study were European Americans, African Americans, Mexican Americans, and Singaporeans from the Population Architecture using Genomics and Epidemiology (PAGE) study. Results. Index variants of AMD, rs1061170 (CFH) and rs10490924 (ARMS2), were associated with AMD at P = 3.05 × 10−8 and P = 6.36 × 10−6, respectively, in European Americans. In general, none of the major AMD index variants generalized to our non-European populations with the exception of rs10490924 in Mexican Americans at an uncorrected P value < 0.05. Four lipid-associated SNPS (LPL rs328, TRIB1 rs6987702, CETP rs1800775, and KCTD10/MVK rs2338104) were associated with AMD in African Americans and Mexican Americans (P < 0.05), but these associations did not survive strict corrections for multiple testing. Conclusions. While most associations did not generalize in the non-European populations, variants within lipid-related genes were found to be associated with AMD. This study highlights the need for larger well-powered studies in non-European populations. PMID:25205864

  6. Achieving Motor Development Milestones at the Age of Three Months May Determine, but Does Not Guarantee, Proper Further Development

    PubMed Central

    Gajewska, Ewa; Sobieska, Magdalena; Kaczmarek, Elżbieta; Suwalska, Aleksandra; Steinborn, Barbara

    2013-01-01

    Proper motor performance at 3rd month is necessary for further motor development. The paper aims to demonstrate the reliability, sensitivity, and predictive value of an original motor performance assessment tool in comparison with the neurological assessment at 3, 6, and 9 months. Children (n = 123), born at term without pre- or perinatal complications, born at term with pre- or perinatal complications, or born preterm, were assessed at the age of 3, 6, and 9 months, by a neurologist and a physiotherapist. The physiotherapist evaluated 15 qualitative features typical for the age of 3 months in the prone and supine positions. The final neurological assessment determined the degree of developmental disorder. Neurological and global physiotherapeutic assessments showed a statistically significant correlation. Qualitative assessment results were very good in healthy children and decreased with worsening neurological diagnoses. Children diagnosed with cerebral palsy did not show proper qualitative features of 3 months when analyzed at 3, 6, and 9 months. Children with delayed motor development revealed minor qualitative performance impairments as early as 3 months but improved with age. Qualitative assessment at 3 months not only facilitates diagnosis of major developmental disorders but is also a good predictor of delayed motor development in children. PMID:24385875

  7. Determinants of suboptimal complementary feeding practices among children aged 6-23 months in four anglophone West African countries.

    PubMed

    Issaka, Abukari I; Agho, Kingsley E; Page, Andrew N; Burns, Penelope L; Stevens, Garry J; Dibley, Michael J

    2015-10-01

    Suboptimal complementary feeding practices have a detrimental impact on a child's growth, health and development in the first two years of life. They lead to child malnutrition, which contributes to the high prevalence of stunting (38%) and underweight (28%) reported for children <5 years of age in Sub-Saharan Africa. This study analysed complementary feeding practices in four anglophone West African countries (Ghana, Liberia, Nigeria and Sierra Leone) using the most recent Demographic and Health Surveys. The study covered 12 623 children aged 6-23 months from four anglophone West African countries (Ghana: 822 children: Liberia: 1458 children, Nigeria: 8786 children and Sierra Leone: 1557 children). Four complementary feeding indicators were examined against a set of individual-, household- and community-level factors, using multiple regression analysis. Multivariate analyses found that lack of post-natal contacts with health workers, maternal illiteracy and geographical region were common determinants of delayed introduction of solid, semi-solid or soft foods across all four countries. Predictors for minimum dietary diversity, minimum meal frequency and minimum acceptable diet included children aged 6-11 months, administrative/geographical region, poorer household income and limited access to media. The authors recommend that the four anglophone West African countries studied should prioritise efforts to improve complementary feeding practices in order to reduce child morbidity and mortality. Interventional studies on complementary feeding should target those from poor and illiterate households.

  8. Determinants of times of appearance of radium-induced osteosarcomas in humans: age at appearance and dose

    SciTech Connect

    Stebbings, J.H.; Lucas, H.F.

    1983-01-01

    Determinants of time-until-tumor for osteosarcoma in US radium cases have been reevaluated. Classically, a minimum induction period (latency period) of about five years has been recognized, but not an expression period. Lack of long induction periods at igh doses has been ascribed to scarcity of subjects at risk. Recent experiments have suggested that induction periods are directly lengthened as doses decrease. Reanalyses of time-until-tumor data for 57 measured female osteosarcoma cases exposed to /sup 226/Ra and /or /sup 228/Ra support new interpretations: time-until-tumor for osteosarcomas is best described by age at tumor appearance, not by induction period; age at diagnosis increases as estimated initial radium intake decreases; and, there exists an expression period which can be truncated at the low end by the minimum induction period (or by age at exposure). The downturn in sarcoma incidence at very high doses is describable as the truncation of the expression period on its early side by the minimum induction period. These results depend strongly on the assumption of homogeneity of time-until-tumor processes in diial workers and in iatrogenic radium exposure cases.

  9. Comparison of DXA Scans and Conventional X-rays for Spine Morphometry and Bone Age Determination in Children.

    PubMed

    Hoyer-Kuhn, Heike; Knoop, Kai; Semler, Oliver; Kuhr, Kathrin; Hellmich, Martin; Schoenau, Eckhard; Koerber, Friederike

    2016-01-01

    Conventional lateral spine and hand radiographs are the standard tools to evaluate vertebral morphometry and bone age in children. Beside bone mineral density analyses, dual-energy X-ray absorptiometry (DXA) measurements with lower radiation exposure provide high-resolution scans which are not approved for diagnostic purposes. Data about the comparability of conventional radiographs and DXA in children are missing yet. The purpose of the trial was to evaluate whether conventional hand and spine radiographs can be replaced by DXA scans to diminish radiation exposure. Thirty-eight children with osteogenesis imperfecta or secondary osteoporosis or short stature (male, n=20; age, 5.0-17.0 yr) were included and assessed once by additional DXA (GE iDXA) of the spine or the left hand. Intraclass correlation coefficients (ICCs) were used to express agreement between X-ray and iDXA assessment. Evaluation of the spine morphometry showed reasonable agreement between iDXA and radiography (ICC for fish-shape, 0.75; for wedge-shape, 0.65; and for compression fractures, 0.70). Bone age determination showed excellent agreement between iDXA and radiography (ICC, 0.97). IDXA-scans of the spine in a pediatric population should be used not only to assess bone mineral density but also to evaluate anatomic structures and vertebral morphometry. Therefore, iDXA can replace some radiographs in children with skeletal diseases.

  10. A germline knowledge based computational approach for determining antibody complementarity determining regions.

    PubMed

    Zhao, Shanrong; Lu, Jin

    2010-01-01

    Determination of framework regions (FRs) and complementarity determining regions (CDRs) in an antibody is essential for understanding the underlying biology as well as antibody engineering and optimization. However, there are no computational algorithms available to delimit an antibody sequence or a library of sequences into FRs and CDRs in a coherent and automatic fashion. Based upon the mapping relationships among mature antibody sequences and their corresponding germline gene segments, a novel computational algorithm has been developed for automatic determination of CDRs. Even though a human can make more than 10(12) different antibody molecules in its preimmune repertoire to fight off invading pathogens, these antibodies are generated from rearrangements of a very limited number of germline variable (V) gene, diversity (D) gene and joining (J) gene segments followed by somatic hypermutation. The framework regions FR1, FR2 and FR3 in mature antibodies are encoded by germline V gene segments, while FR4 is encoded by J gene segments. Since there are only a limited number of germline gene segments, these genes can be pre-delimited to generate a knowledge base of FRs and CDRs. Then for a given antibody sequence, the algorithm scans each pre-delimited gene in knowledge base, finds the best matching V and J segments, and accordingly, identifies the FRs and CDRs. The described algorithm is stringently tested using nearly 25,000 human antibody sequences from NCBI, and it is proven to be very robust. Over 99.7% of antibody sequences can be delimited computationally. Of those delimited sequences, only 0.28% of them have somatic insertions and deletions in FRs, and their corresponding delimited results need manual checking. Another feature of the algorithm is that it is CDR definition independent, and can be easily extended to other CDR definitions besides the most widely used Kabat, Chothia and IMGT definitions. In addition to delimitation of antibody sequences into FRs

  11. Age compositions of flatfish stocks as determined by a new otolithometric method, its application in the estimation of growth, spawning potential and fisheries management

    NASA Astrophysics Data System (ADS)

    Katayama, Satoshi; Yamamoto, Masayuki; Gorie, Shigeaki

    2010-11-01

    We developed an ageing methodology and examined age composition of three flatfish stocks inhabiting the Seto Inland Sea, Japan. Ages were difficult to determine for three-lined tongue sole ( Cynoglossus abbreviates) and ridged-eye flounder ( Pleuronichthys cornutus) because the first year annulus ring was often indistinct; therefore, we used directional change in otolith growth to distinguish it. Sectioning and etching methods were powerful tools for identifying annual checks for red tongue sole ( Cynoglossus joyneri). Using these ageing methods, we determined age-length relationships and growth curves. The age composition of the populations studied and of the landings showed that a large proportion of the latter consisted of individuals under the mean age of sexual maturity, thereby reducing the percent spawning potential ratio (%SPR) to ≈ 20% for all species. These findings suggest that fishing pressure on immature fish is leading to overfishing of these flatfish stocks.

  12. A Novel Physiology-Based Mathematical Model to Estimate Red Blood Cell Lifespan in Different Human Age Groups.

    PubMed

    An, Guohua; Widness, John A; Mock, Donald M; Veng-Pedersen, Peter

    2016-09-01

    Direct measurement of red blood cell (RBC) survival in humans has improved from the original accurate but limited differential agglutination technique to the current reliable, safe, and accurate biotin method. Despite this, all of these methods are time consuming and require blood sampling over several months to determine the RBC lifespan. For situations in which RBC survival information must be obtained quickly, these methods are not suitable. With the exception of adults and infants, RBC survival has not been extensively investigated in other age groups. To address this need, we developed a novel, physiology-based mathematical model that quickly estimates RBC lifespan in healthy individuals at any age. The model is based on the assumption that the total number of RBC recirculations during the lifespan of each RBC (denoted by N max) is relatively constant for all age groups. The model was initially validated using the data from our prior infant and adult biotin-labeled red blood cell studies and then extended to the other age groups. The model generated the following estimate