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Sample records for age possibly reflecting

  1. Reflection, dialogue, and the possibilities of space.

    PubMed

    Kumagai, Arno K; Naidu, Thirusha

    2015-03-01

    To educate physicians who are capable of delivering ethical, socially responsible, patient-centered care, there have been calls for identifying curricular space for reflection on the human and societal dimensions of medicine. These appeals, however, beg the question: What does it mean to devote space in an otherwise busy curriculum for these types of reflection? This Perspective is an attempt to understand the nature of this educational space in terms of its purpose, uses, dynamics, and limitations, and the underlying components that allow reflection and transformation to occur. Reflections on psychosocial themes often take the form of dialogues, which differ from the discussions commonly encountered in clinical settings because they require the engagement of the participants' whole selves--life experiences, backgrounds, personal values, beliefs, and perspectives--in the exchanges. Dialogues allow for the inclusion of affective and experiential dimensions in addition to intellectual/cognitive domains in learning, and for an emphasis on discovering new perspectives, insights, and questions instead of limiting participants solely to an instrumental search for solutions. Although these reflections may vary greatly in their form and settings, the reflective space requires three qualities: safety and confidentiality, an intentional designation of a time apart from the distractions of daily life for reflection and dialogue, and an awareness of the transitional nature--the liminality--of a critically important period of professional identity development. In this open space of reflection and dialogue, one's identity as a humanistic physician takes form. PMID:25426737

  2. The Malleability of Possible Selves and Expectations regarding Aging

    ERIC Educational Resources Information Center

    Bardach, Shoshana H.; Gayer, Christopher C.; Clinkinbeard, Tiffanie; Zanjani, Faika; Watkins, John F.

    2010-01-01

    Many people are apprehensive about old age and their future years. This pilot study sought to improve participants' sense of possibility in, and expectations for, old age. Students and middle-aged volunteers completed a survey including the Expectations Regarding Aging 38-item questionnaire (ERA-38) and a possible-selves questionnaire before and…

  3. Near-Earth asteroids: possible sources from reflectance spectroscopy.

    PubMed

    McFadden, L A; Gaffey, M J; McCord, T B

    1985-07-12

    Spectra of near-Earth asteroids were compared to spectra of selected asteroids, planets, and satellites to determine possible source regions. The diversity of reflectance spectra of the near-Earth asteroids implies different mineralogical compositions and hence more than one source region. The presence of near-Earth asteroid spectral signatures similar to those of certain main-belt asteroids supports models that derive some of these asteroids from the 5:2 Kirkwood gap and the Flora family by gravitational perturbations. Planetary and satellite surfaces are different in composition than the near-Earth asteroids, which is in agreement with theoretical arguments that such bodies should not be sources. Some near-Earth asteroids supply portions of Earth's meteorite flux, but other sources must also contribute.

  4. Male accessory gland inflammation prevalence in type 2 diabetic patients with symptoms possibly reflecting autonomic neuropathy

    PubMed Central

    Condorelli, Rosita A; Vicari, Enzo; Calogero, Aldo E; La Vignera, Sandro

    2014-01-01

    Male accessory gland inflammation or infection (MAGI) is a potentially underdiagnosed complication of type 2 diabetes (DM2); specifically, we reported in a recent study that the frequency of MAGI was 43% among DM2 patients. In previous studies, we have demonstrated that diabetic autonomic neuropathy (DAN) is associated with a peculiar ultrasound characterization of the seminal vesicles (SVs) in DM2 patients. The aim of the present study was to evaluate the frequency of MAGI in two different categories of DM2 patients (i.e. patients with and without symptoms that possibly reflect DAN) and the respective ultrasound characterizations. Sixty DM2 patients with a mean (± s.e.m.) age of 42.0 ± 6.0 years (range: 34–47 years) were classified according to the presence or the absence of symptoms that could possibly reflect DAN (group A: DM2 with symptoms possibly reflecting DAN, n = 28 patients and group B: DM2 without symptoms possibly reflecting DAN, n = 32 patients). The patients in Group A exhibited a significantly higher frequency of MAGI compared with those in group B patients (P < 0.05); moreover, the Group A patients exhibited a significantly higher frequency of ultrasound signs suggestive of vesiculitis (P < 0.05). Finally, the concentrations of lymphocytes but not the concentrations of the leukocytes in the semen were significantly higher (P < 0.05) in group A compared with group B. PMID:24799635

  5. Opening to Possibility: Reflectivity and Reflexivity in Our Teaching

    ERIC Educational Resources Information Center

    Wilhelm, Jeff, Ed.

    2013-01-01

    This commentary explores how teachers can create a culture of tolerance by promoting reflectivity and reflexivity, and considers classroom processes and activities for doing so. "Reflectivity" is considered to be the use of personal values, experiences, and habits to make meaning and is a central tenet of inquiry approaches: to build…

  6. Monitoring bruise age using visible diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    McMurdy, John W.; Duffy, Susan; Crawford, Gregory P.

    2007-02-01

    The ability to determine the age of a bruise of unknown age mechanism is important in matters of domestic and child abuse and forensics. While physicians are asked to make clinical judgment on the age of a bruise using color and tenderness, studies have shown that a physicians estimate is highly inaccurate and in cases no better than chance alone. We present here the temporal progression of reflection spectrum collected from accidentally inflicted contusions in adult and child study participants with a synopsis of the observed phenomena. Reflection spectra collected using a portable fiber optic reflection spectrometer can track the increase in extravasated hemoglobin from trauma caused blood vessel rupture and subsequent removal of this hemoglobin occurring concurrent with an increase in the absorption attributed to the breakdown product bilirubin. We hypothesize that this time dependent pattern can be used to determine the age of an unknown bruise in an individual provided rate constant information for the patient can be determined in a controlled calibration bruise. Using reflection spectra to estimate bruise age can provide a rapid and noninvasive method to improve the ability of physicians in dating the age of a contusion.

  7. Teachers' Reflections on Education in a Global Age

    ERIC Educational Resources Information Center

    Callis, Laura Kyser; Osborn, Daniel

    2014-01-01

    This article presents profiles of and reflections by teachers with international experience, including the authors, who offer insights on education in a global age. The respondents who were colleagues of the authors were interviewed to learn about their K-12 education, insights into and analysis of their experiences teaching abroad, and thoughts…

  8. Possibilities and Limits of Self-Reflection in the Teaching Profession.

    ERIC Educational Resources Information Center

    Bengtsson, Jan

    2003-01-01

    Investigates the possibilities of self-reflection for the teaching profession by relating the problem the philosophy of Rene Descartes, Immanuel Kant, and Edmund Husserl. Explains that in philosophy reflection has always played a major role, while it has not always had a major role in education. Concludes that it is possible to learn from mistakes…

  9. Possible systematic decreases in the age of globular clusters

    SciTech Connect

    Shi, X.; Schramm, D. N.; Dearborn, D. S.P.; Truran, J. W.

    1994-03-01

    The ages of globular clusters inferred from observations depends sensitively on assumptions like the initial helium abundance and the mass loss rate. A high helium abundance (e.g., Y\\approx0.28) or a mass loss rate of \\sim10^{-11}M_\\odot yr^{-1} near the main sequence turn-off region lowers the current age estimate from 14 Gyr to about 10--12 Gyr, significantly relaxing the constraints on the Hubble constant, allowing values as high as 60km/sec/Mpc for a universe with the critical density and 90km/sec/Mpc for a baryon-only universe. Possible mechanisms for the helium enhancement in globular clusters are discussed, as are arguments for an instability strip induced mass loss near the turn-off. Ages lower than 10 Gyr are not possible even with the operation of both of these mechanisms unless the initial helium abundance in globular clusters is >0.30, which would conflict with indirect measurements of helium abundances in globular clusters.

  10. [Authentication of Age of Bloodstains Using UV Visible Reflection Spectrum].

    PubMed

    Gao, Qian-yu; Gao, Shi-ming

    2015-08-01

    The age of bloodstains is tightly related to the time elapsed since the crime was committed. The inference of the time that the crime was committed is of great significance to solve the case, and it was also a difficult problem in judicial authentication. Therefore, establishing a method of rapid determination of bleeding time is very necessary. Using a UV-visible spectrometer with a reflection accessory called ISR-240A and whiteboard as a reference standard, the reflection spectra of blood gauze, aluminum, glass and plastic were measured every hour under the condition of 16 °C and 70% humidity within 8 hours. Using SPSS to process the data, R541/R577 was figured out and linear fitting was completed. The same method was carried on on the gauze of blood at 24 °C. The results showed that, within 8 hours, spectral reflectance values of blood at 541 and 577 nm increased gradually with the passage of injury time. In addition to the R2 of the glass with blood is 0.769, the rest of the R2 were greater than 0.900. The values of F were greater than F0.05 (1, 6) = 5.59. Therefore, the linear regression model is significant meaningful. The method of using a UV-Visible spectrometer without doing any operations of the test samples is simple. Moreover, it does no harm to the further inspection in aspects of personal information, which is suitable for the judicial practice.

  11. Possible Origin of High-Amplitude Reflection Packages (HARPs) in the Canada Basin, Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Lebedeva-Ivanova, Nina; Hutchinson, Deborah; Shimeld, John; Chian, Deping; Hart, Patrick; Jackson, Ruth; Saltus, Richard; Mosher, David

    2013-04-01

    The Canada Basin (CB) of the Arctic Ocean is a semi-enclosed ocean basin surrounded by the Alaskan and Canadian margins to the south and east, the Alpha-Mendeleev Large Igneous Province (AMLIP) to the north and the subsided continental Chukchi Borderland (ChB) to the west. During 2007-2011, US-Canada expeditions collected ~15,000 km multichannel seismic data and sonobuoy reflection and refraction seismic data with average spacing of ~80 km mostly over the CB and AMLIP. High-amplitude reflective packages (HARPs) underlie the mostly flat-lying sediments of CB. Although HARPs are discontinuous in the central CB, they become more continuous toward ChB and AMLIP. HARPs are often the most reflective events in the seismic section, exceeding even the seafloor reflection. Only rarely are reflections seen beneath HARPs. Where best developed, HARPs are ~100-300 ms TWTT, consisting of several high-amplitude wavelets with a pronounced narrow frequency band within the limits of ~10-30 Hz. This character of HARPs is consistent with patterns produced by constructive interference of thin beds (Widess, 1973). Forward modeling of sonobuoy data, synthetic tests, and frequency analysis of the tuning effect suggest that HARPs are composed of a series of alternating high- and low-velocity layers. The high-velocity layers are ~100-200 m thick with P-velocities of ~3.5-4.5 km/s. The low-velocity layers are about half as thick with velocities of ~2-3 km/s. A broad range of possible interpretations of rock composition exists from these velocities, e.g. sandstone and interbedded shale (Prince Patrick Island, Harrison and Brent, 2005); or tholeiitic basalts flows and sediments (Voring volcanic margin, Olanke and Eldholm, 1994); or sills and sediments (Newfoundland margin, Peron-Pinvidic et all, 2010). HARP can be associated with several origins. In the central and southern CB, where oceanic spreading is interpreted, HARPs are discontinuous among high-relief, but otherwise low

  12. The possible role of Brazilian promontory in Little Ice Age

    NASA Astrophysics Data System (ADS)

    Zou, Youjia; Xi, Xiangying

    2014-09-01

    The Gulf Stream, one of the strongest currents in the world, transports approximately 31 Sv of water (Kelly and Gille, 1990; Baringer and Larsen, 2001; Leaman et al., 1995) and 1.3 × 1015 W (Larsen, 1992) of heat into the Atlantic Ocean, and warms the vast European continent. Thus any change of the Gulf Stream could lead to the climate change in the European continent, and even worldwide (Bryden et al., 2005). Past studies have revealed a diminished Gulf Stream and oceanic heat transport that was possibly associated with a southward migration of intertropical convergence zone (ITCZ) and may have contributed to Little Ice Age (AD ∼1200 to 1850) in the North Atlantic (Lund et al., 2006). However, the causations of the Gulf Stream weakening due to the southward migration of the ITCZ remain uncertain. Here we use satellite observation data and employ a model (oceanic general circulation model - OGCM) to demonstrate that the Brazilian promontory in the east coast of South America may have played a crucial role in allocating the equatorial currents, while the mean position of the equatorial currents migrates between northern and southern hemisphere in the Atlantic Ocean. Northward migrations of the equatorial currents in the Atlantic Ocean have little influence on the Gulf Stream. Nevertheless, southward migrations, especially abrupt large southward migrations of the equatorial currents, can lead to the increase of the Brazil Current and the significant decrease of the North Brazil Current, in turn the weakening of the Gulf Stream. The results from the model simulations suggest the mean position of the equatorial currents in the Atlantic Ocean shifted at least 180-260 km southwards of its present-day position during the Little Ice Age based on the calculations of simple linear equations and the OGCM simulations.

  13. Reflections on the golden age of Columbia psychology.

    PubMed

    Thorne, F C

    1976-04-01

    This paper discusses the Golden Age (1920-1940) of the Columbia University psychology department and analyzes some of the sources of its strengths and weaknesses. Much of the credit goes to Robert S. Woodworth, the dean of American experimental psychology, who set up the objective eclectic orientation of the department, recruited a remarkable group of competent faculty members, and above all kept up a cooperative unified spirit in the department. Because the Columbia University psychology department was so influential during its Golden Age, its organization, staffing and departmental characteristics are analyzed. Probably the key to its success was the capability of a guiding genius, Robert S. Woodworth, who gathered a remarkable group of scholars about him. Woodworth's objective eclectic orientation provided the broadest possible approach within a rigorous experimental-statistical orientation. Woodworth's scholarly approach pervaded the department so that many of his colleagues also wrote pioneering encyclopedic works in their particular fields of specialization. The writings of the Columbia psychologists truly shaped the field.

  14. Reflections on the challenges and possibilities of journal publication in science education

    NASA Astrophysics Data System (ADS)

    Milne, Catherine; Siry, Christina; Mueller, Michael

    2015-12-01

    In this editorial we reflect on the intersections between the review and publishing policies of Cultural Studies of Science Education (CSSE) and the challenges and possibilities in global science education publishing. In particular we discuss the tensions associated with open or closed review policies, the hegemony of English as a language of publication, and reflect on some of the common challenges experienced by editors and authors from different contexts. We draw on the paper set in this issue consisting of five papers focused on publishing in various contexts, and elaborate several central questions for the field of science education and the dissemination of knowledges.

  15. Possible role of alteration of aldehyde's scavenger enzymes during aging.

    PubMed

    Davydov, Vadim V; Dobaeva, Nataly M; Bozhkov, Anatoly I

    2004-01-01

    Apoptosis in tissues is induced by different kind of signals including endogenous aldehydes, such as 4-hydroxy-2, 3-nonenal. The accumulation rate of aldehydes in the cell is affected by conditions of oxidative stress. In the cell, aldehydes can be metabolized by various isoforms of aldehyde dehydrogenase, aldehyde reductase, and glutathione-S-transferase. There is evidence suggesting that the catalytic properties of these enzymes change during ontogenesis, and that aging is accompanied by their reduced activities. These functional changes may contribute substantially to the alteration in the organism sensitivity to damaging action of stress factors during aging, to age-related modulation of the action of endogenous aldehydes as a signal for apoptosis, and finally, to the origin of diseases associated with aging. In this context, the stimulation of enzymes' expression, and the activation of the catalytic properties of enzymes responsible for catabolism of endogenous aldehydes could become a perspective direction in increasing the organism resistance to the action of damaging factors during aging.

  16. Possible spinel absorption bands in S-asteroid visible reflectance spectra

    NASA Technical Reports Server (NTRS)

    Hiroi, T.; Vilas, F.; Sunshine, J. M.

    1994-01-01

    Minor absorption bands in the 0.55 to 0.7 micron wavelength range of reflectance spectra of 10 S asteroids have been found and compared with those of spinel-group minerals using the modified Gaussian model. Most of these S asteroids are consistently shown to have two absorption bands around 0.6 and 0.67 micron. Of the spinel-group minerals examined in this study, the 0.6 and 0.67 micron bands are most consistent with those seen in chromite. Recently, the existence of spinels has also been detected from the absorption-band features around 1 and 2 micron of two S-asteroid reflectance spectra, and chromite has been found in a primitive achondrite as its major phase. These new findings suggest a possible common existence of spinel-group minerals in the solar system.

  17. Spaceflight and ageing: reflecting on Caenorhabditis elegans in space.

    PubMed

    Honda, Yoko; Honda, Shuji; Narici, Marco; Szewczyk, Nathaniel J

    2014-01-01

    The prospect of space travel continues to capture the imagination. Several competing companies are now promising flights for the general population. Previously, it was recognized that many of the physiological changes that occur with spaceflight are similar to those seen with normal ageing. This led to the notion that spaceflight can be used as a model of accelerated ageing and raised concerns about the safety of individuals engaging in space travel. Paradoxically, however, space travel has been recently shown to be beneficial to some aspects of muscle health in the tiny worm Caenorhabditis elegans. C. elegans is a commonly used laboratory animal for studying ageing. C. elegans displays age-related decline of some biological processes observed in ageing humans, and about 35% of C. elegans' genes have human homologs. Space flown worms were found to have decreased expression of a number of genes that increase lifespan when expressed at lower levels. These changes were accompanied by decreased accumulation of toxic protein aggregates in ageing worms' muscles. Thus, in addition to spaceflight producing physiological changes that are similar to accelerated ageing, it also appears to produce some changes similar to delayed ageing. Here, we put forward the hypothesis that in addition to the previously well-appreciated mechanotransduction changes, neural and endocrine signals are altered in response to spaceflight and that these may have both negative (e.g. less muscle protein) and some positive consequences (e.g. healthier muscles), at least for invertebrates, with respect to health in space. Given that changes in circulating hormones are well documented with age and in astronauts, our view is that further research into the relationship between metabolic control, ageing, and adaptation to the environment should be productive in advancing our understanding of the physiology of both spaceflight and ageing.

  18. The Possibility of Public Education in an Instrumentalist Age

    ERIC Educational Resources Information Center

    Higgins, Chris

    2011-01-01

    In our increasingly instrumentalist culture, debates over the privatization of schooling may be beside the point. Whether we hatch some new plan for chartering or funding schools, or retain the traditional model of government-run schools, the ongoing instrumentalization of education threatens the very possibility of public education. Indeed, in…

  19. Movement Planning Reflects Skill Level and Age Changes in Toddlers

    ERIC Educational Resources Information Center

    Chen, Yu-ping; Keen, Rachel; Rosander, Kerstin; Von Hofsten, Claes

    2010-01-01

    Kinematic measures of children's reaching were found to reflect stable differences in skill level for planning for future actions. Thirty-five toddlers (18-21 months) were engaged in building block towers (precise task) and in placing blocks into an open container (imprecise task). Sixteen children were retested on the same tasks a year later.…

  20. The problem of calibration: A possible way to overcome the drawbacks of age models

    NASA Astrophysics Data System (ADS)

    Goswami, B.; Heitzig, J.; Rehfeld, K.; Marwan, N.; Kurths, J.

    2012-04-01

    Constructing a meaningful age model from a set of radiocarbon age-depth measurements made on a palaeoclimatic archive is the crucial backbone of all proxy-based research carried out thereafter. Significant progress in the development of Monte Carlo based interpolation techniques and Bayesian methods has been made recently, targeting the uncertainties of radiocarbon dating, which then reflect meaningfully as time domain errors in the proxy vs. time relationship. However, one primary limitation of these approaches is the debatable assumption of Gaussianity of the errors in calibrated ages as calibration often results in highly irregular and non-trivial probability distributions of the age for every measurement. Here, we present a method that circumvents this limitation by focussing on the construction of the proxy vs. time relationship rather than emphasising on the estimation of an age-depth relation as the intermediary step. Our method is based on a simple analysis of the involved probabilistic uncertainties and the use of (preferably non-parametric) regression methods that give an estimate of the uncertainty of regression at every point as well. With the appropriate use of Bayes' Theorem we then provide a regression-based estimator for the proxy measurements and compute the respective distribution parameters (such as mean and variance) that quantify the uncertainties of the proxy in the time domain. We verify this method with the help of an artificial data set involving the accumulation history of a simulated core and noisy radiocarbon dating and proxy measurements made on it. To our best knowledge, this is the first method that manages to overcome the fundamental problem of irregular distributions induced by calibration of radiocarbon ages. We feel that this approach shall enable us to look at the problem of dating uncertainties in a new light and open up newer possibilities for studying not only speleothem proxies but, more generally, from other palaeoclimatic

  1. Effects of diffuse and specular reflections on the perceived age of facial skin

    NASA Astrophysics Data System (ADS)

    Arce-Lopera, Carlos; Igarashi, Takanori; Nakao, Keisuke; Okajima, Katsunori

    2012-05-01

    Age perception is a better biomarker of skin aging than chronological age. However, the optical cues that determine the perception of human skin age are difficult to assess given the complex interactions between light and the multi layered structure of the skin. The aim of the present study is to clarify the independent contribution of both diffuse and specular reflection components to the skin age perception. First, according to our results, subjects were able to estimate the age of skin only by using the diffuse reflection component. Moreover, we showed that inclusion of the specular reflection component added on average 5 years to their age estimation. Second, by artificially manipulating the specular component, we concluded that the luminance distribution affects the perceived age of the skin.

  2. [Is it possible to reduce health inequalities in old age?].

    PubMed

    Michel, Jean-Pierre; Herrmann, François; Zekry, Dina

    2012-01-01

    Analysis of prospective data collected between 1984 and 2008 by the CERN medical team (European Centre of Nuclear Research, Geneva) concerning 2040 former employees who were retired or had died stimulated our interest on the impact of inequalities in socioeconomic conditions, employment, lifestyle and classical risk factors on health and life expectancy. Such inequalities explain differences in life expectancy, potentially reaching several decades, between rich and poor countries (France vs Swaziland), but also within a given country (USA), a given city (Glasgow) or even a given enterprise (CERN) where all employees have the same level of healthcare insurance and access to treatment. Classical cardiovascular and neurovascular risk factors (smoking, arterial hypertension and lipid disorders) interact with socioeconomic status, intelligence, education, emotions and job responsibility/complexity, precipitating or preventing cardiovascular events. The same is true of dementia, for which midlife risk factors (obesity, arterial hypertension and hypercholesterolemia) should be considered in the psychosocioeconomic context, which influences cognitive reserves and thus affects the risk and severity of dementia in old age. Thus, in addition to lifestyle and classical risk factors, socioeconomic status appears as a major health determinant, by imposing behaviors and habits and by determining access to healthcare. PMID:23259343

  3. Movement planning reflects skill level and age changes in toddlers.

    PubMed

    Chen, Yu-ping; Keen, Rachel; Rosander, Kerstin; von Hofsten, Claes

    2010-01-01

    Kinematic measures of children's reaching were found to reflect stable differences in skill level for planning for future actions. Thirty-five toddlers (18-21 months) were engaged in building block towers (precise task) and in placing blocks into an open container (imprecise task). Sixteen children were retested on the same tasks a year later. Longer deceleration as the hand approached the block for pickup was found in the tower task compared with the imprecise task, indicating planning for the second movement. More skillful toddlers who could build high towers had a longer deceleration phase when placing blocks on the tower than toddlers who built low towers. Kinematic differences between the groups remained a year later when all children could build high towers. PMID:21077868

  4. Investigating possible earthquake-related structure beneath the southern Illinois Basin from seismic reflection

    USGS Publications Warehouse

    McBride, J.H.; Sargent, M.L.; Potter, C.J.

    1997-01-01

    The relationship between seismicity and faults observed on seismic reflection profiles from the New Madrid Seismic Zone (NMSZ) in the central Mississippi Valley has been intensively studied for the past 15 years. However, comparable studies relating reflector sequences and earthquakes in the southern Illinois Basin, located northeast of the NMSZ, have not been undertaken. This study investigates the possible relationship between the source parameters of the November 9, 1968, magnitude (mbLg) 5.5 earthquake (a NNE-trending, previously interpreted west-dipping reverse fault at 21.2 ?? 5.4 km depth) in southern Illinois, and a zone of moderately dipping reflectors in crystalline (?) basement observed on a nearby high-quality seismic reflection profile. The 1968 event was the twentieth century's largest magnitude earthquake in the southern Illinois region. The zone of dipping basement reflectors is part of a broad prominent sequence, in which reflectors are subhorizontal or inclined with a strong west-dipping component, that appears beneath the Wabash Valley Fault System and extends to the west beneath the Illinois Basin where it steepens and plunges deeper into the crust over the 1968 hypocenter. More than one interpretation of the dipping reflector zone is admissible, including intrusion of igneous sills or thrust faults or both within a localized shear zone. The dipping reflector zone cannot be traced from the basement into the overlying Phanerozoic sedimentary section or associated directly with any particular previously mapped fault. If a tectonic interpretation is correct, the correlation between the 1968 reverse fault event and the reflector zone may mean that such quakes are nucleating along a blind compressional structure in the crystalline basement of southern Illinois, possibly analogous to the recent destructive southern California earthquakes.

  5. Melodic Contour Identification Reflects the Cognitive Threshold of Aging.

    PubMed

    Jeong, Eunju; Ryu, Hokyoung

    2016-01-01

    Cognitive decline is a natural phenomenon of aging. Although there exists a consensus that sensitivity to acoustic features of music is associated with such decline, no solid evidence has yet shown that structural elements and contexts of music explain this loss of cognitive performance. This study examined the extent and the type of cognitive decline that is related to the contour identification task (CIT) using tones with different pitches (i.e., melodic contours). Both younger and older adult groups participated in the CIT given in three listening conditions (i.e., focused, selective, and alternating). Behavioral data (accuracy and response times) and hemodynamic reactions were measured using functional near-infrared spectroscopy (fNIRS). Our findings showed cognitive declines in the older adult group but with a subtle difference from the younger adult group. The accuracy of the melodic CITs given in the target-like distraction task (CIT2) was significantly lower than that in the environmental noise (CIT1) condition in the older adult group, indicating that CIT2 may be a benchmark test for age-specific cognitive decline. The fNIRS findings also agreed with this interpretation, revealing significant increases in oxygenated hemoglobin (oxyHb) concentration in the younger (p < 0.05 for Δpre - on task; p < 0.01 for Δon - post task) rather than the older adult group (n.s for Δpre - on task; n.s for Δon - post task). We further concluded that the oxyHb difference was present in the brain regions near the right dorsolateral prefrontal cortex. Taken together, these findings suggest that CIT2 (i.e., the melodic contour task in the target-like distraction) is an optimized task that could indicate the degree and type of age-related cognitive decline. PMID:27378907

  6. Melodic Contour Identification Reflects the Cognitive Threshold of Aging

    PubMed Central

    Jeong, Eunju; Ryu, Hokyoung

    2016-01-01

    Cognitive decline is a natural phenomenon of aging. Although there exists a consensus that sensitivity to acoustic features of music is associated with such decline, no solid evidence has yet shown that structural elements and contexts of music explain this loss of cognitive performance. This study examined the extent and the type of cognitive decline that is related to the contour identification task (CIT) using tones with different pitches (i.e., melodic contours). Both younger and older adult groups participated in the CIT given in three listening conditions (i.e., focused, selective, and alternating). Behavioral data (accuracy and response times) and hemodynamic reactions were measured using functional near-infrared spectroscopy (fNIRS). Our findings showed cognitive declines in the older adult group but with a subtle difference from the younger adult group. The accuracy of the melodic CITs given in the target-like distraction task (CIT2) was significantly lower than that in the environmental noise (CIT1) condition in the older adult group, indicating that CIT2 may be a benchmark test for age-specific cognitive decline. The fNIRS findings also agreed with this interpretation, revealing significant increases in oxygenated hemoglobin (oxyHb) concentration in the younger (p < 0.05 for Δpre - on task; p < 0.01 for Δon – post task) rather than the older adult group (n.s for Δpre - on task; n.s for Δon – post task). We further concluded that the oxyHb difference was present in the brain regions near the right dorsolateral prefrontal cortex. Taken together, these findings suggest that CIT2 (i.e., the melodic contour task in the target-like distraction) is an optimized task that could indicate the degree and type of age-related cognitive decline. PMID:27378907

  7. Melodic Contour Identification Reflects the Cognitive Threshold of Aging.

    PubMed

    Jeong, Eunju; Ryu, Hokyoung

    2016-01-01

    Cognitive decline is a natural phenomenon of aging. Although there exists a consensus that sensitivity to acoustic features of music is associated with such decline, no solid evidence has yet shown that structural elements and contexts of music explain this loss of cognitive performance. This study examined the extent and the type of cognitive decline that is related to the contour identification task (CIT) using tones with different pitches (i.e., melodic contours). Both younger and older adult groups participated in the CIT given in three listening conditions (i.e., focused, selective, and alternating). Behavioral data (accuracy and response times) and hemodynamic reactions were measured using functional near-infrared spectroscopy (fNIRS). Our findings showed cognitive declines in the older adult group but with a subtle difference from the younger adult group. The accuracy of the melodic CITs given in the target-like distraction task (CIT2) was significantly lower than that in the environmental noise (CIT1) condition in the older adult group, indicating that CIT2 may be a benchmark test for age-specific cognitive decline. The fNIRS findings also agreed with this interpretation, revealing significant increases in oxygenated hemoglobin (oxyHb) concentration in the younger (p < 0.05 for Δpre - on task; p < 0.01 for Δon - post task) rather than the older adult group (n.s for Δpre - on task; n.s for Δon - post task). We further concluded that the oxyHb difference was present in the brain regions near the right dorsolateral prefrontal cortex. Taken together, these findings suggest that CIT2 (i.e., the melodic contour task in the target-like distraction) is an optimized task that could indicate the degree and type of age-related cognitive decline.

  8. Life-History Related Differences in Possible Selves in Very Old Age

    ERIC Educational Resources Information Center

    Hoppmann, Christiane; Smith, Jacqui

    2007-01-01

    The impact of early life events that take place under specific historical and societal circumstances on adult development have rarely been investigated in old age. We examined whether having started a family in young adulthood was related to the contents of possible selves generated by women aged 85 to 100+ in the Berlin Aging Study (N = 129; M…

  9. Suppressed vitrinite reflectance in the Ferron coalbed gas fairway, central Utah: Possible influence of overpressure

    USGS Publications Warehouse

    Quick, J.C.; Tabet, D.E.

    2003-01-01

    Chemical and thermoplastic properties of coals in the Ferron coalbed methane fairway indicate that coals in the north are of higher rank than coals in the south. Measured vitrinite reflectance does not accurately show this variation of coal rank. Although vitrinite reflectance in the southern and central part of the fairway is consistent with other measures of coal rank, suppressed vitrinite reflectance is observed in the north where methane contents are relatively high. This coincidence of suppressed reflectance and relatively high coalbed methane yields may be significant. We speculate that the suppressed reflectance values result from a burial history where overpressure developed during the early stages of coalification and persisted until recent uplift and cooling; such instances may be diagnostic of prospective coalbed methane targets elsewhere. ?? 2003 Published by Elsevier B.V.

  10. Possible modes of coral-reef development at Molokai, Hawaii, inferred from seismic-reflection profiling

    USGS Publications Warehouse

    Barnhardt, W.A.; Richmond, B.M.; Grossman, E.E.; Hart, P.

    2005-01-01

    High-resolution, seismic-reflection data elucidate the late Quaternary development of the largest coral-reef complex in the main Hawaiian Islands. Six acoustic facies were identified from reflection characteristics and lithosome geometry. An extensive, buried platform with uniformly low relief was traced beneath fore-reef and marginal shelf environments. This highly reflective surface dips gently seaward to ???130 m depth and locally crops out on the seafloor. It probably represents a wave-cut platform or ancient reef flat. We propose alternative evolutionary models, in which sea-level changes have modulated the development of reef systems, to explain the observed stratigraphic relationships. The primary difference between the models is the origin of the underlying antecedent surface, which arguably could have formed during either regression/lowstand or subsequent transgression. ?? Springer-Verlag 2005.

  11. The Possibilities and Constraints of Multimedia as a Basis for Critical Reflection

    ERIC Educational Resources Information Center

    Jones, Liz; McNamara, Olwen

    2004-01-01

    The use of video evidence as a vehicle for promoting discussion and critical reflection is well established in educational literature in the field of professional development and is gradually becoming more accepted as a research method. There is general agreement also that in relation to image-based research the combination of video evidence of…

  12. What Is Policy? 21 Years Later: Reflections on the Possibilities of Policy Research

    ERIC Educational Resources Information Center

    Ball, Stephen J.

    2015-01-01

    This paper is a reflection on "What is policy? Texts, Trajectories and Tool Boxes," which was first published in 1993, in "Discourse: Studies in the Cultural Politics of Education." It looks back to what the 1993 paper was trying to do and at some of the developments of the ideas first sketched there in my later work, in…

  13. The Possibility of Cosmopolitan Learning: Reflecting on Future Directions for Diversity Teacher Education in Australia

    ERIC Educational Resources Information Center

    Reid, Carol; Sriprakash, Arathi

    2012-01-01

    This paper is situated in the re-visioning ethos that has been part of the genealogy of multicultural education. In the context of teacher education, the authors ask: where to now? In this paper, they reflect on their design and delivery of a new undergraduate unit offered by the School of Education, University of Western Sydney. The unit…

  14. Possible Origin of Improved High Temperature Performance of Hydrothermally Aged Cu/Beta Zeolite Catalysts

    SciTech Connect

    Peden, Charles HF; Kwak, Ja Hun; Burton, Sarah D.; Tonkyn, Russell G.; Kim, Do Heui; Lee, Jong H.; Jen, H. W.; Cavattaio, Giovanni; Cheng, Yisun; Lambert, Christine

    2012-04-30

    The hydrothermal stability of Cu/beta NH3 SCR catalysts are explored here. In particular, this paper focuses on the interesting ability of this catalyst to maintain and even enhance high-temperature performance for the "standard" SCR reaction after modest (900 °C, 2 hours) hydrothermal aging. Characterization of the fresh and aged catalysts was performed with an aim to identify possible catalytic phases responsible for the enhanced high temperature performance. XRD, TEM and 27Al NMR all showed that the hydrothermally aging conditions used here resulted in almost complete loss of the beta zeolite structure between 1 and 2 hours aging. While the 27Al NMR spectra of 2 and 10 hour hydrothermally-aged catalysts showed significant loss of a peak associated with tetrahedrally-coordinated Al species, no new spectral features were evident. Two model catalysts, suggested by these characterization data as possible mimics of the catalytic phase formed during hydrothermal aging of Cu/beta, were prepared and tested for their performance in the "standard" SCR and NH3 oxidation reactions. The similarity in their reactivity compared to the 2 hour hydrothermally-aged Cu/beta catalyst suggests possible routes for preparing multi-component catalysts that may have wider temperature windows for optimum performance than those provided by current Cu/zeolite catalysts.

  15. Bilateral force reflection for teleoperators with masters and slaves with dissimilar and possibly redundant kinematics

    NASA Astrophysics Data System (ADS)

    Jansen, J. F.; Babcock, S. M.

    1989-11-01

    Several bilateral control techniques and methods for exploiting redundant slaves are investigated as a part of research to develop and analyze bilateral, force-reflecting control methodologies for teleoperator systems with kinematic dissimilar masters and slaves. The study indicates that, with force/torque sensing at the wrist, and an impedance type of controller with the appropriate joint compensation, a significant improvement in performance and controllability of a teleoperator system can be achieved.

  16. Parents and Children Reading and Reflecting Together: The Possibilities of Family Retrospective Miscue Analysis

    ERIC Educational Resources Information Center

    Kabuto, Bobbie

    2009-01-01

    The possibilities of using Retrospective Miscue Analysis (RMA) with families to help parents and children investigate the reading process, are discussed with the goal of assisting parents to better understand their children's reading strengths. Highlighting a case study from a Family RMA project, this article illustrates how Family RMA provided a…

  17. Differential Gene Expression Profiles Reflecting Macrophage Polarization in Aging and Periodontitis Gingival Tissues.

    PubMed

    Gonzalez, O A; Novak, M J; Kirakodu, S; Stromberg, A; Nagarajan, R; Huang, C B; Chen, K C; Orraca, L; Martinez-Gonzalez, J; Ebersole, J L

    2015-01-01

    Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1 and M2) of these cells in inflammation, adaptive immune responses and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a non-human primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3-23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7 and TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype.

  18. Sporting Bodies, Ageing, Narrative Mapping and Young Team Athletes: An Analysis of Possible Selves

    ERIC Educational Resources Information Center

    Phoenix, Cassandra; Sparkes, Andrew C.

    2007-01-01

    Drawing on life history data generated from interviews with young athletes at an English university, this paper explores the narrative maps provided to them by older team members and the ways in which these influence perceptions of self-ageing. Three possible selves associated with mid-life emerged from the analysis for detailed focus. These are…

  19. The functional-cognitive meta-theoretical framework: Reflections, possible clarifications and how to move forward.

    PubMed

    Barnes-Holmes, Dermot; Hussey, Ian

    2016-02-01

    The functional-cognitive meta-theoretical framework has been offered as a conceptual basis for facilitating greater communication and cooperation between the functional/behavioural and cognitive traditions within psychology, thus leading to benefits for both scientific communities. The current article is written from the perspective of two functional researchers, who are also proponents of the functional-cognitive framework, and attended the "Building Bridges between the Functional and Cognitive Traditions" meeting at Ghent University in the summer of 2014. The article commences with a brief summary of the functional approach to theory, followed by our reflections upon the functional-cognitive framework in light of that meeting. In doing so, we offer three ways in which the framework could be clarified: (a) effective communication between the two traditions is likely to be found at the level of behavioural observations rather than effects or theory, (b) not all behavioural observations will be deemed to be of mutual interest to both traditions, and (c) observations of mutual interest will be those that serve to elaborate and extend existing theorising in the functional and/or cognitive traditions. The article concludes with a summary of what we perceive to be the strengths and weaknesses of the framework, and a suggestion that there is a need to determine if the framework is meta-theoretical or is in fact a third theoretical approach to doing psychological science.

  20. Exfoliative cytology: A possible tool in age estimation in forensic odontology

    PubMed Central

    Shetty, Devi Charan; Wadhwan, Vijay; Khanna, Kaveri Surya; Jain, Anshi; Gupta, Amit

    2015-01-01

    Introduction: Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster because the age at death, birth date, and year of death as well as gender can guide investigators to the correct identity among a large number of possible matches. Objective: The study was undertaken with an aim to estimate the age of an individual from their buccal smears by comparing the average cell size using image analysis morphometric software. Materials and Methods: Buccal smears were collected from 100 apparently healthy individuals. After fixation in 95% alcohol, the smears were stained using standard Papanicolaou laboratory procedure. The average cell size was measured using Dewinter's image analysis software version 4.3. Statistical analysis of the data was done using one-way ANOVA, Bonferroni procedures. Results: The results showed significant decrease in average cell size of individual with increase in age. The difference was highly significant in age group of above 60 years. Conclusion: Age-related alterations are observed in buccal smears. PMID:25709323

  1. Ages and possible provenance of the sediments of the Capim River kaolin, northern Brazil

    NASA Astrophysics Data System (ADS)

    Sousa, D. J. L.; Varajão, A. F. D. C.; Yvon, J.; Scheller, T.; Moura, C. A. V.

    2007-06-01

    Provenance studies carried out on the soft and flint facies of the Capim River kaolin (northern Brazil) trace the possible sources of sediments that host the ore. Pb-Pb evaporation geochronology was applied to four predominant morphologic classes of detrital zircons, and the ages obtained were compared to the main age intervals of the rocks surrounding the Capim kaolin district (CKD). Four major plateau ages (2.15, 2.02, 1.87, and 1.51 Ga) were defined for both soft and flint facies, indicating a common source for the kaolin and provenance from NE and SW. The 2.15 and 2.02 Ga ages correlate with the granitic bodies of the Gurupi region, located NE of the study area. The 1.87 and 1.51 Ga ages show provenance from the Amazon Craton, the former from the southern portion, in the Carajás region, and the latter from the southwestern portion. Although less abundant, Archean (3.18, 2.79, and 2.55 Ga) and Neoproterozoic ages (0.8 and 0.51 Ga) also correlate with the SW and NE provenances, respectively. The first corresponds to the oldest rocks of the Carajás region and the second to the rocks of the Gurupi region, corresponding to the Brasiliano orogeny.

  2. The San Gabriel mountains bright reflective zone: Possible evidence of young mid-crustal thrust faulting in southern California

    USGS Publications Warehouse

    Ryberg, T.; Fuis, G.S.

    1998-01-01

    During the Los Angeles Region Seismic Experiment (LARSE), a reflection/retraction survey was conducted along a line extending northeastward from Seal Beach, California, to the Mojave Desert, crossing the Los Angeles basin and San Gabriel Mountains. Shots and receivers were spaced most densely through the San Gabriel Mountains for the purpose of obtaining a combined reflection and refraction image of the crust in that area. A stack of common-midpoint (CMP) data reveals a bright reflective zone, 1-s thick, that dominates the stack and extends throughout most of the mid-crust of the San Gabriel Mountains. The top of this zone ranges in depth from 6 s (???18-km depth) in the southern San Gabriel Mountains to 7.5 s (???23-km depth) in the northern San Gabriel Mountains. The zone bends downward beneath the surface traces of the San Gabriel and San Andreas faults. It is brightest between these two faults, where it is given the name San Gabriel Mountains 'bright spot' (SGMBS). and becomes more poorly defined south of the San Gabriel fault and north of the San Andreas fault. The polarity of the seismic signal at the top of this zone is clearly negative, and our analysis suggests it represents a negative velocity step. The magnitude of the velocity step is approximately 1.7 km/s. In at least one location, an event with positive polarity can be observed 0.2 s beneath the top of this zone, indicating a thickness of the order of 500 m for the low-velocity zone at this location. Several factors combine to make the preferred interpretation of this bright reflective zone a young fault zone, possibly a 'master' decollement. (1) It represents a significant velocity reduction. If the rocks in this zone contain fluids, such a reduction could be caused by a differential change in fluid pressure between the caprock and the rocks in the SGMBS; near-lithostatic fluid pressure is required in the SGMBS. Such differential changes are believed to occur in the neighborhood of active fault

  3. Reflections

    NASA Astrophysics Data System (ADS)

    Greiner, Walter

    2012-01-01

    This symposium was very special. It was topical: Some of the most outstanding problems in Nuclear Physics were discussed: Superheavy elements; extremely neutron rich elements, as well as nuclei with strangeness and their possible creation in the cosmos and on earth; the nuclear equation of state has to be identified within strongly compressed and hot nuclear matter as it appears in nucleus-nucleus encounters; giant nuclear systems which are short lived (˜ 10-19 - 10-20 seconds) and extremely important for identifying the vacuum decay in overcritical electric fields (this is a very fundamental process - the most fundamental one in Quantum Electrodynamics!); astrophysical centers of extreme high density around which magnificent sun-like objects are Kepler-orbiting are discovered in our Galaxy by R. Genzel and colleagues (these centers are no black holes those don't exist at all because repulsive gravitational forces may play an important role - the pseudocomplex general relativity eliminates the Schwarzschild singularity); network physics for distributing energy (nuclear, wind, sun, tides,...) all over Europe (and over the world) is basic for energy consumption now and even more so in future. We heard wonderful talks and I am grateful to all the friends and speakers (from Russia, America, Europe and India) for coming to Goa. It was a great symposium! Particular thanks go to Professor Bikash Sinha and especially to Professor Debades Bandyopadhyay from Calcutta who had the idea for and organized this Goa-symposium....

  4. Age-associated sperm DNA methylation alterations: possible implications in offspring disease susceptibility.

    PubMed

    Jenkins, Timothy G; Aston, Kenneth I; Pflueger, Christian; Cairns, Bradley R; Carrell, Douglas T

    2014-07-01

    Recent evidence demonstrates a role for paternal aging on offspring disease susceptibility. It is well established that various neuropsychiatric disorders (schizophrenia, autism, etc.), trinucleotide expansion associated diseases (myotonic dystrophy, Huntington's, etc.) and even some forms of cancer have increased incidence in the offspring of older fathers. Despite strong epidemiological evidence that these alterations are more common in offspring sired by older fathers, in most cases the mechanisms that drive these processes are unclear. However, it is commonly believed that epigenetics, and specifically DNA methylation alterations, likely play a role. In this study we have investigated the impact of aging on DNA methylation in mature human sperm. Using a methylation array approach we evaluated changes to sperm DNA methylation patterns in 17 fertile donors by comparing the sperm methylome of 2 samples collected from each individual 9-19 years apart. With this design we have identified 139 regions that are significantly and consistently hypomethylated with age and 8 regions that are significantly hypermethylated with age. A representative subset of these alterations have been confirmed in an independent cohort. A total of 117 genes are associated with these regions of methylation alterations (promoter or gene body). Intriguingly, a portion of the age-related changes in sperm DNA methylation are located at genes previously associated with schizophrenia and bipolar disorder. While our data does not establish a causative relationship, it does raise the possibility that the age-associated methylation of the candidate genes that we observe in sperm might contribute to the increased incidence of neuropsychiatric and other disorders in the offspring of older males. However, further study is required to determine whether, and to what extent, a causative relationship exists. PMID:25010591

  5. Astrocytic plasticity as a possible mediator of the cognitive improvements after environmental enrichment in aged rats.

    PubMed

    Sampedro-Piquero, P; De Bartolo, Paola; Petrosini, Laura; Zancada-Menendez, C; Arias, J L; Begega, A

    2014-10-01

    Currently, little is known about the effect of environmental enrichment (EE) on astrocytic plasticity, especially during aging. Given the newly discovered role of the astrocytes in regulating the synaptic transmission and thereby, the cognitive functions, we aimed to study the impact of EE on the performance in a spatial memory task and on the number and morphology of GFAP immunopositive cells in the dorsal hippocampus. After two months of EE (3 h/per day), the animals were tested in the Radial-Arm Water Maze (RAWM) for four days, with six daily trials. Next, we analyzed the changes in the GFAP immunopositive cells in CA1, CA3 and Dentate Gyrus (DG). Behavioral results showed that, even in advanced ages, EE improved the performance in a spatial memory task. Also, we found that aged rats submitted to EE had more GFAP immunopositive cells in the DG and more complex astrocytes, revealed by Sholl analysis, in all hippocampal subfields with respect to the other experimental conditions. Interestingly, the learning of a spatial memory task produced more morphological complexity and higher levels of GFAP immunopositive cells with regard to a standard control group, but not at the same level of the enriched groups. Thus, it is possible that the plastic changes found in the hippocampal astrocytes after EE are involved in a brain reserve to cope with age-related cognitive impairments.

  6. Effect of Mild Heating on Human Lens Epithelial Cells: A Possible Model of Lens Aging

    PubMed Central

    Zhang, Keke; Zhu, Xiangjia; Lu, Yi

    2016-01-01

    This study aims to investigate the effect of mild heating on lens epithelial cells and to explore its possibility as an in vitro model for lens aging. Human lens epithelial cells (LECs) were heated at 50 °C for a cellular lens aging study. Analysis of the head group order of lens membranes was performed using Laurdan labeling. Immunofluorescence was performed to detect changes in α-crystallin expression and its cellular distribution. The chaperone-like activity of α-crystallin was also assessed. After mild heating, α-crystallin in LECs showed a tendency towards accumulation around the nucleus. The membrane head group environment of lens epithelial cells became more fluid with increasing time of exposure to mild heating, as indicated by increased water penetration. Furthermore, the chaperone activity of α-crystallin decreased, and suggests a relatively lower protective effect on other functional proteins in LECs. Thus, compared to the mild heating model based on lens tissue, this cellular model could provide a more convenient and accurate method for studying lens aging in vitro, including changes in membrane head group order in each cell, the real-time observation of crystallin distribution, and the monitoring of functional changes in the chaperone activity of crystallins as a result of aging. PMID:27725687

  7. Sirtuin Functions in Female Fertility: Possible Role in Oxidative Stress and Aging

    PubMed Central

    Tatone, Carla; Vitti, Maurizio; Santini, Silvano; D'Alessandro, Anna Maria

    2015-01-01

    In search for strategies aimed at preventing oxidative threat to female fertility, a possible role of sirtuins has emerged. Sirtuins (silent information regulator 2 (Sir2) proteins), NAD+ dependent enzymes with deacetylase and/or mono-ADP-ribosyltransferase activity, are emerging as key antiaging molecules and regulators in many diseases. Recently, a crucial role for SIRT1 and SIRT3, the main components of sirtuin family, as sensors and guardians of the redox state in oocytes, granulosa cells, and early embryos has emerged. In this context, the aim of the present review is to summarize current knowledge from research papers on the role of sirtuins in female fertility with particular emphasis on the impairment of SIRT1 signalling with oocyte aging. On this basis, the authors wish to build up a framework to promote research on the possible role of sirtuins as targets for future strategies for female fertility preservation. PMID:26075037

  8. Bioenergetic functions of sleep and activity rhythms and their possible relevance to aging.

    PubMed

    Berger, R J

    1975-01-01

    The hypothesis is proposed that sleep constitutes a period of dormancy in which energy is conserved to partially offset the increased energy demands of homeothermy. Phylogenetic data indicate that the complete psysiological and behavioral manifestations of sleep are unique to homeotherms; furthermore "ontogeny recapitulates phylogeny" in the parallel development of slow wave sleep and thermoregulation as exemplified in the opossum. Thus, sleep constitutes a state of reduced metabolism that may represent a variation on the theme of dormancy, functionally lying on a continuum of energy conservation processes, ranging from inactivity and estivation to torpor and hibernation. The high amounts of sleep in infancy may involve conservation of energy and its consequent availability for growth. Decreased amounts of stage 4 and total sleep with aging in humans may represent reduced energy demands reflected by parallel declines in basal metabolic rate and physical activity. Disruptions of circadian rhythms of sleep and wakefulness in humans produce impairments in mood and performance independent of total amounts of sleep obtained, and reduce the amplitude of physiological rhythms. It is suggested that aging processes might also be affected by such disruptions in activity rhythms.

  9. [Attenuated Total Reflection Infrared Spectroscopy for Degradation Profile of High Density Polyethylene after Weathering Aging].

    PubMed

    Guo, Jun-jun; Yan, Hua; Bao, He-bin; Wang, Xue-mei; Hu, Zhi-de; Yang, Jian-jian

    2015-06-01

    High density polyethylene (HDPE) was widely used as rotational packaging case in the material reserve field. The chemical changes of HDPE, exposed to particular climatic conditions of tropic marine atmosphere for one year-long in Wanning Hainan, were elucidated by the attenuated total reflection infrared spectroscopy (ATR-FTIR). The structural changes were studied qualitatively, mainly from the polymeric chain breaking, branching and oxidation to distinguish the degradation profile. The variations of crystallinity & carbonyl index were also studied quantitatively according to the characteristic peaks intensity & area ratio. Finally, the relationships between structural changes and mechanical properties were investigated. The results showed that the polymeric chain breaking & branching play a leading role before 3 months in the aging progress. Then oxidation phenomena gradually takes place during 3-6 months. The chain branching & oxidation were predominant factors after 6 months. Nine months later, the oxidation was saturated gradually. Furthermore, the aging process is positively correlated to the temperature and irradiation. After 12 months aging, the carbonyl index increased by 112 times and crystallinity was 10% higher than before. The tensile/bending modulus deceased faster than tensile/bending strength of HDPE. The linear degree of tensile modulus and carbonyl index was 0.97. The degree of linearity of tensile strength and crystallinity calculated by feature bands (720-730 cm(-1)) was 0.96. It showed that the mechanical properties of HDPE can be speculated from the structural changes by ATR-FTIR. PMID:26601359

  10. [Attenuated Total Reflection Infrared Spectroscopy for Degradation Profile of High Density Polyethylene after Weathering Aging].

    PubMed

    Guo, Jun-jun; Yan, Hua; Bao, He-bin; Wang, Xue-mei; Hu, Zhi-de; Yang, Jian-jian

    2015-06-01

    High density polyethylene (HDPE) was widely used as rotational packaging case in the material reserve field. The chemical changes of HDPE, exposed to particular climatic conditions of tropic marine atmosphere for one year-long in Wanning Hainan, were elucidated by the attenuated total reflection infrared spectroscopy (ATR-FTIR). The structural changes were studied qualitatively, mainly from the polymeric chain breaking, branching and oxidation to distinguish the degradation profile. The variations of crystallinity & carbonyl index were also studied quantitatively according to the characteristic peaks intensity & area ratio. Finally, the relationships between structural changes and mechanical properties were investigated. The results showed that the polymeric chain breaking & branching play a leading role before 3 months in the aging progress. Then oxidation phenomena gradually takes place during 3-6 months. The chain branching & oxidation were predominant factors after 6 months. Nine months later, the oxidation was saturated gradually. Furthermore, the aging process is positively correlated to the temperature and irradiation. After 12 months aging, the carbonyl index increased by 112 times and crystallinity was 10% higher than before. The tensile/bending modulus deceased faster than tensile/bending strength of HDPE. The linear degree of tensile modulus and carbonyl index was 0.97. The degree of linearity of tensile strength and crystallinity calculated by feature bands (720-730 cm(-1)) was 0.96. It showed that the mechanical properties of HDPE can be speculated from the structural changes by ATR-FTIR.

  11. Electrocortical Dynamics Reflect Age-Related Differences in Movement Kinematics among Children and Adults

    PubMed Central

    Kagerer, Florian A.; Momen, Bahram; Hatfield, Bradley D.; Clark, Jane E.

    2011-01-01

    Previous neuroimaging and behavioral studies demonstrated structural and functional changes in the motor system across childhood. However, it is unclear what functionally relevant electrocortical processes underlie developmental differences in motor planning and control during multijoint, goal-directed movements. The current study characterized age-related differences in electrocortical processes during the performance of discrete aiming movements in children and adults. Electroencephalography and movement kinematics were recorded from 3 groups of participants (n = 15 each): young children (mean 6.7 years), older children (mean 10.2 years), and adults (mean 22.1 years). Age-related differences were evident in the electroencephalographic (EEG) signals. First, young children exhibited less movement-related activity in task-relevant motor areas compared with adults (movement-related cortical potentials). Second, young children exhibited greater activation (less alpha power) of the frontal areas and less activation of the parietal areas as compared with the other groups. At the behavioral level, young children made slower and jerkier movements, with less consistent directional planning compared with older children and adults. Significant correlations were also found between EEG and movement kinematic measures. Taken together, the results of this study provide evidence that age-related differences in the quality of motor planning and performance are reflected in the differences in electrocortical dynamics among children and adults. PMID:20805237

  12. Highlighting the impact of aging on type I collagen: label-free investigation using confocal reflectance microscopy and diffuse reflectance spectroscopy in 3D matrix model.

    PubMed

    Guilbert, Marie; Roig, Blandine; Terryn, Christine; Garnotel, Roselyne; Jeannesson, Pierre; Sockalingum, Ganesh D; Manfait, Michel; Perraut, François; Dinten, Jean-Marc; Koenig, Anne; Piot, Olivier

    2016-02-23

    During aging, alterations of extracellular matrix proteins contribute to various pathological phenotypes. Among these alterations, type I collagen cross-linking and associated glycation products accumulation over time detrimentally affects its physico-chemical properties, leading to alterations of tissue biomechanical stability. Here, different-age collagen 3D matrices using non-destructive and label-free biophotonic techniques were analysed to highlight the impact of collagen I aging on 3D constructs, at macroscopic and microscopic levels. Matrices were prepared with collagens extracted from tail tendons of rats (newborns, young and old adults) to be within the physiological aging process. The data of diffuse reflectance spectroscopy reveal that aging leads to an inhibition of fibril assembly and a resulting decrease of gel density. Investigations by confocal reflectance microscopy highlight poor-fibrillar structures in oldest collagen networks most likely related to the glycation products accumulation. Complementarily, an infrared analysis brings out marked spectral variations in the Amide I profile, specific of the peptidic bond conformation and for carbohydrates vibrations as function of collagen-age. Interestingly, we also highlight an unexpected behavior for newborn collagen, exhibiting poorly-organized networks and microscopic features close to the oldest collagen. These results demonstrate that changes in collagen optical properties are relevant for investigating the incidence of aging in 3D matrix models.

  13. Highlighting the impact of aging on type I collagen: label-free investigation using confocal reflectance microscopy and diffuse reflectance spectroscopy in 3D matrix model

    PubMed Central

    Terryn, Christine; Garnotel, Roselyne; Jeannesson, Pierre; Sockalingum, Ganesh D.; Manfait, Michel; Perraut, François; Dinten, Jean-Marc; Koenig, Anne; Piot, Olivier

    2016-01-01

    During aging, alterations of extracellular matrix proteins contribute to various pathological phenotypes. Among these alterations, type I collagen cross-linking and associated glycation products accumulation over time detrimentally affects its physico-chemical properties, leading to alterations of tissue biomechanical stability. Here, different-age collagen 3D matrices using non-destructive and label-free biophotonic techniques were analysed to highlight the impact of collagen I aging on 3D constructs, at macroscopic and microscopic levels. Matrices were prepared with collagens extracted from tail tendons of rats (newborns, young and old adults) to be within the physiological aging process. The data of diffuse reflectance spectroscopy reveal that aging leads to an inhibition of fibril assembly and a resulting decrease of gel density. Investigations by confocal reflectance microscopy highlight poor-fibrillar structures in oldest collagen networks most likely related to the glycation products accumulation. Complementarily, an infrared analysis brings out marked spectral variations in the Amide I profile, specific of the peptidic bond conformation and for carbohydrates vibrations as function of collagen-age. Interestingly, we also highlight an unexpected behavior for newborn collagen, exhibiting poorly-organized networks and microscopic features close to the oldest collagen. These results demonstrate that changes in collagen optical properties are relevant for investigating the incidence of aging in 3D matrix models. PMID:26885896

  14. Old age is a part of living: student reflections on intergenerational service-learning.

    PubMed

    Kalisch, Hilary R; Coughlin, Deanna R; Ballard, Sharon M; Lamson, Angela

    2013-01-01

    Analysis of student journals examined the effect intergenerational service-learning had upon undergraduate students' attitudes and perceptions of older adults. Students (N = 102) engaged in 12 hours of service-learning with older adults that included writing structured reflection journals. Coding involved open, axial, and selective coding with common themes identified from the journals. Results revealed a positive attitude shift toward older adults over the course of the semester, greater comfort with the idea of aging, and a propensity to describe the experience as being personally and professionally influential in their own lives. Students also reported increased course understanding and a desire to continue volunteering. Implications for intergenerational service-learning are discussed.

  15. Possibility of the detection and identification of substance at long distance using the noisy reflected THz pulse under real conditions

    NASA Astrophysics Data System (ADS)

    Trofimov, Vyacheslav A.; Varentsova, Svetlana A.; Trofimov, Vladislav V.

    2015-05-01

    We show possibility of the detection and identification of substance at long distance (several metres, for example) using the THz pulse reflected from the object under the real conditions: at room temperature and humidity of about 70%. The main feature of this report consists in a demonstration of the detection and identification of substance using the computer processing of the noisy THz pulse. Amplitude of the useful signal is less than the amplitude of a noise. Nevertheless, it is possible to detect "fingerprint" frequencies of substance if these frequencies are known and the SDA method is used together with new assessments for probability estimation for presence of detected frequencies. Essential restrictions of the commonly used THz TDS method for the detection and identification under real conditions (at long distance about 3.5 m and at a high relative humidity more than 50%) are demonstrated using the physical experiment with chocolate bar and thick paper bag. We show also that the THz TDS method detects spectral features of dangerous substances even in the THz signals measured in laboratory conditions (at distance 30-40 cm from the receiver and at a low relative humidity less than 2%); the n-Si and p-Si semiconductors were used as neutral substances. However, the integral correlation and likeness criteria, based on SDA method, allow us to detect the absence of dangerous substances in the samples. Current results show feasibility of using the discussed method of the THz pulsed spectroscopy for the counter-terrorism problem.

  16. Modes of Reflection: Is It Possible to Use Both Individual and Collective Reflection to Reconcile the "Three-Party Knowledge Interests" in Workplace Learning?

    ERIC Educational Resources Information Center

    Walsh, Anita

    2009-01-01

    Reflection is a complex process that many learners do not find easy, and facilitating their reflection requires a sophisticated pedagogy. The focus in this process is normally on the development of the individual professionals and their own particular practice, with the assumption that enhanced individual performance will prove of benefit to the…

  17. Immune Responses in Age Related Macular Degeneration and a possible Long Term Therapeutic Strategy for Prevention

    PubMed Central

    Nussenblatt, Robert B.; Lee, Richard W.J.; Chew, Emily; Wei, Lai; Liu, Baoying; Sen, Nida; Dick, Andrew D.; Ferris, Frederick L.

    2014-01-01

    Purpose To describe the immune alterations associated with, age related macular degeneration (AMD). Based on these findings, to offer an approach to possibly prevent the expression of late disease. Design Perspective Methods Review of the existing literature dealing with epidemiology, models, and immunologic findings in patients. Results Significant genetic associations have been identified and reported, but environmentally induced (including epigenetic) changes are also an important consideration. Immune alterations include a strong interleukin-17 family signature as well as marked expression of these molecules in the eye. Oxidative stress as well as other homeostatic altering mechanisms occurs throughout life. With this immune dysregulation there is a rationale for considering immunotherapy. Indeed immunotherapy has been shown to affect the late stages of AMD. Conclusion Immune dysregulation appears to be an underlying alteration in AMD as in other diseases thought to be degenerative and due to aging. Parainflammation and immunosensescence may importantly contribute to the development of disease. The role of complement factor H still needs to be better defined but in light of its association with ocular inflammatory conditions such as sarcoidosis, it does not appear to be unique to AMD but rather may be a marker for retinal pigment epithelium function. With the strong interleukin-17 family signature and the need to treat early on in the disease process, oral tolerance may be considered to prevent disease progression. PMID:24709810

  18. Bone Turnover Does Not Reflect Skeletal Aging in Older Hispanic Men with Type 2 Diabetes

    NASA Technical Reports Server (NTRS)

    Rianon, N.; McCormick, J.; Ambrose, C.; Smith, S. M.; Fisher-Hoch, S.

    2016-01-01

    were identified in women. Bone turnover in older Hispanic men with DM2 in our study does not reflect normal pattern of skeletal aging. It is unclear why similar results were not identified in women. We will continue to follow this cohort to investigate longitudinal trend of changes of bone turnover and its relationship with HbA1c in both men and women of this cohort.

  19. Structural variation of proterozoic dikes in central Superior Province: A possible reflection of post-Archean shield deformation

    NASA Technical Reports Server (NTRS)

    Ernst, R. E.

    1983-01-01

    Preliminary work is reported on the use of two structural parameters, dike dip and thickness, as possible depth-of-exposure indicators in the Central Superior Province. The data demonstrate systematic variations in the dip and thickness of 2.6 and 1.14 Ga. dikes across the Central Superior Province and are tentatively interpreted to result from post intrusion deformation. Combination of these results with additional structural and paleomagnetic data from dikes of all gas may permit detailed mapping both spatially and temporally of crustal deformation in this part of the Canadian Shield. Although dike dip and thickness data apparently reflect crustal exposure level as given by host rock metamorphic grade (ranging from subgreenschist to granulite), these post-orogenic dikes themselves are at most only weakly metamorphosed. This requires that regional isotherms dropped dramatically after the Kenoran orogeny (2.65 Ga.) and prior to emplacement of the earlist post-orogenic swarm (Matachewan-Hearst) at 2.6 Ga.

  20. Cyclooxygenase inhibition augments central blood pressure and aortic wave reflection in aging humans.

    PubMed

    Barnes, Jill N; Casey, Darren P; Hines, Casey N; Nicholson, Wayne T; Joyner, Michael J

    2012-06-15

    The augmentation index and central blood pressure increase with normal aging. Recently, cyclooxygenase (COX) inhibitors, commonly used for the treatment of pain, have been associated with transient increases in the risk of cardiovascular events. We examined the effects of the COX inhibitor indomethacin (Indo) on central arterial hemodynamics and wave reflection characteristics in young and old healthy adults. High-fidelity radial arterial pressure waveforms were measured noninvasively by applanation tonometry before (control) and after Indo treatment in young (25 ± 5 yr, 7 men and 6 women) and old (64 ± 6 yr, 5 men and 6 women) subjects. Aortic systolic (control: 115 ± 3 mmHg vs. Indo: 125 ± 5 mmHg, P < 0.05) and diastolic (control: 74 ± 2 mmHg vs. Indo: 79 ± 3 mmHg, P < 0.05) pressures were elevated after Indo treatment in older subjects, whereas only diastolic pressure was elevated in young subjects (control: 71 ± 2 mmHg vs. Indo: 76 ± 1 mmHg, P < 0.05). Mean arterial pressure increased in both young and old adults after Indo treatment (P < 0.05). The aortic augmentation index and augmented pressure were elevated after Indo treatment in older subjects (control: 30 ± 5% vs. Indo 36 ± 6% and control 12 ± 1 mmHg vs. Indo: 18 ± 2 mmHg, respectively, P < 0.05), whereas pulse pressure amplification decreased (change: 8 ± 3%, P < 0.05). In addition, older subjects had a 61 ± 11% increase in wasted left ventricular energy after Indo treatment (P < 0.05). In contrast, young subjects showed no significant changes in any of the variables of interest. Taken together, these results demonstrate that COX inhibition with Indo unfavorably increases central wave reflection and augments aortic pressure in old but not young subjects. Our results suggest that aging individuals have a limited ability to compensate for the acute hemodynamic changes caused by systemic COX inhibition.

  1. Attenuation of rat ischemic brain damage by aged garlic extracts: a possible protecting mechanism as antioxidants.

    PubMed

    Numagami, Y; Sato, S; Ohnishi, S T

    1996-08-01

    Effects of an aged garlic extract and its thioallyl components on rat brain ischemia were examined using a middle cerebral artery occlusion model and a transient global ischemia model. In focal ischemia, an aged garlic extract, S-allyl cysteine (SAC), Allyl sulfide (AS) or Allyl disulfide (ADS) was administered 30 min prior to ischemic insult. Three days after ischemic insult, water contents of both ischemic and contralateral hemispheres were measured to assess the degree of ischemic damage. The water content of the ischemic control (no drug treatment) group was 81.50 +/- 0.07% (mean +/- SEM). It was significantly reduced with the administration of 300 mg/kg of SAC; the water content was 80.66 +/- 0.11% (P < 0.001). The histological observation using 2,3,5-triphenyltetrazolium chloride staining demonstrated that the administration of SAC reduced infarct volume. Neither AS nor ADS was effective. In global ischemia, the production of reactive oxygen species (ROS) was measured ex vivo using a spin-trapping agent, alpha-phenyl-N-tert-butylnitrone, and electron paramagnetic resonance spectroscopy. The production of ROS had two peaks; first at 5 min and second at 20 min after reperfusion. Both SAC and 7-nitro indazole, a nitric oxide synthase inhibitor, did not attenuate the amount of ROS produced at the first peak, but did the amount of the second peak. A possible involvement of peroxinitrite, which may be formed from superoxide and nitric oxide and is known to be highly toxic in ischemia/reperfusion injury of the brain, was suggested.

  2. Growth of the Maritime Continent and its possible contribution to recurring Ice Ages

    NASA Astrophysics Data System (ADS)

    Molnar, Peter; Cronin, Timothy W.

    2015-03-01

    The areal extent of the Maritime Continent (the islands of Indonesia and surrounding region) has grown larger by ~60% since 5 Ma. We argue that this growth might have altered global climate in two ways that would have contributed to making recurring Ice Ages possible. First, because rainfall over the islands of the Maritime Continent not only is heavier than that over the adjacent ocean but also correlates with the strength of the Walker Circulation, the growth of the Maritime Continent since 5 Ma may have contributed to the cooling of the eastern tropical Pacific since that time. Scaling relationships between the strength of the Walker Circulation and rainfall over the islands of the Maritime Continent and between sea surface temperature (SST) of the eastern tropical Pacific and the strength of easterly wind stress suggest that the increase in areal extent of islands would lead to a drop in that SST of 0.75°C. Although only a fraction of the 3-4°C decrease in SSTs between the eastern and western tropical Pacific, the growth of the Maritime Continent may have strengthened the Walker Circulation, increased the east-west temperature gradient across the Pacific and thereby enabled ice sheets to wax and wane over Canada since 3 Ma. Second, because the weathering of basaltic rock under warm, moist conditions extracts CO2 from the atmosphere more rapidly than weathering of other rock or of basalt under cooler or drier conditions, the increase in weathering due to increasing area of basalt in the Maritime Continent may have drawn down enough CO2 from the atmosphere to affect global temperatures. Simple calculations suggest that increased weathering of basalt might have lowered global temperatures by 0.25°C, possibly important for the overall cooling.

  3. Lead-uranium ratio of siliceous pitchblende from Great Bear Lake, N. W. T., Canada, and its possible age

    USGS Publications Warehouse

    Marble, J.P.

    1936-01-01

    1. A sample of pitchblende from LaBine Point, Echo Bay, Great Bear Lake, N. W. T., Canada, yields a "corrected" lead-ratio of 0.193, corresponding to an age of 1323 million years. 2. As the atomic weight and isotopic composition of the lead, and the Pa/UI ratio of this same sample have been determined, ages, etc., calculated by different methods should agree. This agreement has not been obtained in all instances, and possible reasons have been outlined. 3. The age found indicates that a possible Keewatin granite may be the source of the pitch-blende.

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

    NASA Astrophysics Data System (ADS)

    Brandt, Timothy D.; Huang, Chelsea X.

    2015-07-01

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

  5. Targeting Senescent Cells: Possible Implications for Delaying Skin Aging: A Mini-Review.

    PubMed

    Velarde, Michael C; Demaria, Marco

    2016-01-01

    Senescent cells are induced by a wide variety of stimuli. They accumulate in several tissues during aging, including the skin. Senescent cells secrete proinflammatory cytokines, chemokines, growth factors, and proteases, a phenomenon called senescence-associated secretory phenotype (SASP), which are thought to contribute to the functional decline of the skin as a consequence of aging. Due to the potential negative effects of the SASP in aged organisms, drugs that selectively target senescent cells represent an intriguing therapeutic strategy to delay aging and age-related diseases. Here, we review studies on the role of senescent cells in the skin, with particular emphasis on the age-related mechanisms and phenotypes associated with excessive accumulation of cellular senescence. We discuss the aberrant behavior of senescent cells in aging and how the different signaling pathways associated with survival and secretion of senescent cells can be engaged for the development of targeted therapies.

  6. The Possible Mechanism of Advanced Glycation End Products (AGEs) for Alzheimer’s Disease

    PubMed Central

    Ko, Shun-Yao; Ko, Hshin-An; Chu, Kuo-Hsiung; Shieh, Tzong-Ming; Chi, Tzong-Cherng; Chen, Hong-I; Chang, Weng-Cheng; Chang, Shu-Shing

    2015-01-01

    Amyloid precursor protein (APP) has been modified by β and γ-secretase that cause amyloid deposits (plaques) in neuronal cells. Glyceraldhyde-derived AGEs has been identified as a major source of neurotoxicity in Alzheimer’s disease (AD). In a previous study, we demonstrated that glyceraldehyde-derived AGEs increase APP and Aβ via ROS. Furthermore, the combination of AGEs and Aβ has been shown to enhance neurotoxicity. In mice, APP expression is increased by tail vein injection of AGEs. This evidence suggests a correlation between AGEs and the development of AD. However, the role played by AGEs in the pathogenesis of AD remains unclear. In this report, we demonstrate that AGEs up-regulate APP processing protein (BACE and PS1) and Sirt1 expression via ROS, but do not affect the expression of downstream antioxidant genes HO-1 and NQO-1. Moreover, we found that AGEs increase GRP78 expression and enhance the cell death-related pathway p53, bcl-2/bax ratio, caspase 3. These results indicate that AGEs impair the neuroprotective effects of Sirt1 and lead to neuronal cell death via ER stress. Our findings suggest that AGEs increase ROS production, which stimulates downstream pathways related to APP processing, Aβ production, Sirt1, and GRP78, resulting in the up-regulation of cell death related pathway. This in-turn enhances neuronal cell death, which leads to the development of AD. PMID:26587989

  7. Exploring Career Options and Possibilities Later in Life: Adult (Age 50-75) Career Development Survey

    ERIC Educational Resources Information Center

    Smith, Angela Carmella

    2009-01-01

    A survey instrument was developed entitled the "Adult (age 50-75) Career Development Survey" (ACDS) to provide an empirical foundation for understanding the current needs of individuals age 50-75 and learning about their attitudes toward, willingness to, and experience in using career counseling and technology in making decisions on whether or not…

  8. Ageing horses by an examination of their incisor teeth: an (im)possible task?

    PubMed

    Muylle, S; Simoens, P; Lauwers, H

    1996-03-30

    It is generally considered that the age of a horse can be determined by examining its incisor teeth. However, the criteria used to determine age from dental configurations differ widely. The existence of this variety of rules and guidelines was the challenge for the present examination. Detailed descriptions of the incisor teeth of 212 horses of registered age were recorded and the results were compared with the age criteria of various authors. The time at which teeth were shed and the appearance of dental stars seemed to be more reliable features than the disappearance of the cups. The disappearance of the marks occurred four years later than usually stated. Other criteria, such as the presence of the seven-year notch and Galvayne's groove, were too variable and inconsistent to be reliable for the determination of age. PMID:8730689

  9. Ageing horses by an examination of their incisor teeth: an (im)possible task?

    PubMed

    Muylle, S; Simoens, P; Lauwers, H

    1996-03-30

    It is generally considered that the age of a horse can be determined by examining its incisor teeth. However, the criteria used to determine age from dental configurations differ widely. The existence of this variety of rules and guidelines was the challenge for the present examination. Detailed descriptions of the incisor teeth of 212 horses of registered age were recorded and the results were compared with the age criteria of various authors. The time at which teeth were shed and the appearance of dental stars seemed to be more reliable features than the disappearance of the cups. The disappearance of the marks occurred four years later than usually stated. Other criteria, such as the presence of the seven-year notch and Galvayne's groove, were too variable and inconsistent to be reliable for the determination of age.

  10. Dark nests and egg colour in birds: a possible functional role of ultraviolet reflectance in egg detectability

    PubMed Central

    Avilés, Jesús M; Soler, Juan J; Pérez-Contreras, Tomás

    2006-01-01

    Owing to the conspicuousness of ultraviolet (UV) colour in dark environments, natural selection might have selected UV egg coloration because it would enhance egg detectability by parents in murky nests. Here, we tested this hypothesis by using comparative and experimental approaches. First, we studied variation in egg coloration of 98 species of European passerines measured using UV–visible reflectance spectrometry (300–700 nm) in relation to nesting habits. Analyses based on raw data and controlling for phylogenetic distances both at the species and the family levels revealed that hole-nester species produced eggs with higher UV reflectance than those nesting in open habitats. The experimental approach consisted of the manipulation of UV reflectance of the experimental eggs introduced outside the nest-cup of the hole-nester spotless starling Sturnus unicolor and the study of the retrieval of these eggs. Ultraviolet-reflecting eggs (controls) were more frequently retrieved to the nest-cup than non-reflecting (–UV) eggs. These results were not due to ‘–UV’ eggs being recognized by starlings as parasitic because when a parasitic egg is detected, starlings removed it from the nest-box. Therefore, these results are consistent with the hypothesis that UV egg colours are designed to provide highly detectable targets for parent birds in dark nest environments. PMID:17015364

  11. Subretinal Hyper-Reflective Material in the Comparison of Age-related Macular Degeneration Treatments Trials

    PubMed Central

    Willoughby, Alex S.; Ying, Gui-shuang; Toth, Cynthia A.; Maguire, Maureen G.; Burns, Russell E.; Grunwald, Juan E.; Daniel, Ebenezer; Jaffe, Glenn J.

    2015-01-01

    Objective To evaluate the association of subretinal hyper-reflective material (SHRM) with visual acuity (VA), geographic atrophy (GA) and scar in the Comparison of Age related Macular Degeneration Treatments Trials (CATT) Design Prospective cohort study within a randomized clinical trial. Participants The 1185 participants in CATT. Methods Participants were randomly assigned to ranibizumab or bevacizumab treatment monthly or as-needed. Masked readers graded scar and GA on fundus photography and fluorescein angiography images, SHRM on time domain (TD) and spectral domain (SD) optical coherence tomography (OCT) throughout 104 weeks. Measurements of SHRM height and width in the fovea, within the center 1mm2, or outside the center 1mm2 were obtained on SD-OCT images at 56 (n=76) and 104 (n=66) weeks. VA was measured by certified examiners. Main Outcome Measures SHRM presence, location and size, and associations with VA, scar, and GA. Results Among all CATT participants, the percentage with SHRM at enrollment was 77%, decreasing to 68% at 4 weeks after treatment and 54% at 104 weeks. At 104 weeks, scar was present more often in eyes with persistent SHRM than eyes with SHRM that resolved (64% vs. 31%; p<0.0001). Among eyes with detailed evaluation of SHRM at weeks 56 (n=76) and 104 (n=66), mean [SE] VA letter score was 73.5 [2.8], 73.1 [3.4], 65.3 [3.5], and 63.9 [3.7] when SHRM was absent, present outside the central 1mm2, present within the central 1mm2 but not the foveal center, or present at the foveal center (p=0.02). SHRM was present at the foveal center in 43 (30%), within the central 1mm2 in 21 (15%) and outside the central 1mm2 in 19 (13%). When SHRM was present, the median maximum height in microns under the fovea, within the central 1 mm2 including the fovea and anywhere within the scan was 86; 120; and 122, respectively. VA was decreased with greater SHRM height and width (p<0.05). Conclusions SHRM is common in eyes with NVAMD and often persists after anti

  12. Dwell in Possibility: PLAR and e-Portfolios in the Age of Information and Communication Technologies

    ERIC Educational Resources Information Center

    Brown, Judith O.

    2011-01-01

    Emily Dickinson wrote, "I dwell in Possibility--A fairer House than Prose--More Numerous of Windows--Superior--for Doors" (p. 657). Dickinson's simple yet profound reference to the expansive nature of poetry over prose may be taken as a metaphor for the possibilities of information and communication technologies (ICTs) over written modes of…

  13. Measles antibodies in cord blood in Portugal: Possible consequences for the recommended age of vaccination.

    PubMed

    Gonçalves, Guilherme; Nunes, Carla; Mesquita, João Rodrigo; Nascimento, Maria São José; Frade, João

    2016-05-23

    The optimum age to give the first dose of measles vaccine must balance the risks of disease and vaccine failure. Both are influenced by the levels of transplacentally acquired maternal antibodies. This study was conducted in the Obstetric service of Portuguese hospital, in 2012-2013. Mothers were recruited after informed consent. Measles IgG was measured in 206 cord sera, using a commercial immunoassay. Geometric mean concentrations (and 95% CI) were 1849mIU/ml (1196-2857) and 790mIU/ml (618-1008) in cord sera of newborns from unvaccinated and vaccinated mothers respectively. Maternal age and vaccination status were both associated with the concentration in cord sera, but maternal age was the major predictor. The likely explanation is the same already mentioned in other studies: as a vaccination program progresses, vaccination coverage increases as measles incidence decreases. That results newborns from younger vaccinated mothers having less measles antibodies while the older mothers are more likely to have been infected with the wild virus. As the proportion of vaccinated mothers increase, developed countries tend to anticipate the recommended age of the first dose to 12 months of age. Models using hypothetical measles antibody decay rates in infancy were explored. Anticipating the first dose of MMR1 in Portugal to the age of 12 months might have not been the best decision but results were not conclusive, and arguments supporting or not the anticipation were discussed. PMID:27109563

  14. [Is it possible to "cancel" aging process of cell cultures under optimal conditions for cultivation?].

    PubMed

    Bozhkov, A I; Kovaleva, M K; Menzianova, N G

    2011-01-01

    The characteristics of the cells epigenotypes Dunaliella viridis Teod. in the process of chronological and replicative aging were investigated. By 40th day of accumulative cultivation (which coincided with the stationary growth phase) DNA content in the cells of Dunaliella viridis increased 2 times, triacylglycerides 3 times, beta-carotene and carbonyl proteins 2 times, RNA content decreased in comparison with cells in exponential growth phase, i. e., the 40th day of growth of culture forms the age-related epigenotype. 4 received subcultures were being transplanted during 2 years in mid-logarithmic growth phase (subculture-10), early stationary phase of growth (subculture-20), in the mid-stationary growth phase (subculture-30), and late stationary growth phase (subculture-40). It is shown that epigenotype of subculture-10 remained unchanged over 2 years of cultivation, i. e., it does not manifest replicative aging. At the same time, the subculture-20, although long enough (at least 40 passages), maintained epigenotype characteristic of young cultures, and showed age-related changes. Pronounced age-dependent changes of epigenotype in the course of cultivation were identified for subculture-30, and subculture-40 was characterized by unstable epigenotype. Thus, cultivation conditions determine the intensity of replicative aging in Dunaliella viridis.

  15. Age of Diagnosis Influences Serologic Responses in Children with Crohn Disease: A Possible Clue to Etiology?

    PubMed Central

    Markowitz, James; Kugathasan, Subra; Dubinsky, Marla; Mei, Ling; Crandall, Wallace; LeLeiko, Neal; Oliva-Hemker, Maria; Rosh, Joel; Evans, Jonathan; Mack, David; Otley, Anthony; Pfefferkorn, Marian; Bahar, Ron; Vasiliauskas, Eric; Wahbeh, Ghassan; Silber, Gary; Quiros, J. Antonio; Wrobel, Iwona; Nebel, Justin; Landers, Carol; Picornell, Yoanna; Targan, Stephan; Lerer, Trudy; Hyams, Jeffrey

    2009-01-01

    Crohn disease (CD) is often associated with antibodies to microbial antigens. Differences in immune response may offer clues to the pathogenesis of the disease. AIM To examine the influence of age at diagnosis on serologic response in children with CD. METHODS Data were drawn from 3 North American multicenter pediatric IBD research consortia. At or shortly after diagnosis, pANCA, ASCA IgA, ASCA IgG, anti-ompC and anti-CBir1 were assayed. Results were compared as a function of age at CD diagnosis (0–7 years vs 8–15 years). RESULTS 705 children (79 <8 yr of age at diagnosis, 626 ≥8yr) were studied. Small bowel CD was less frequent in the younger group (48.7% vs 72.6%; p<0.0001) while colonic involvement was comparable (91.0% vs 86.5%). ASCA IgA and IgG were seen in <20% of those 0–7 yr compared to nearly 40% of those 8–15 yr (p<0.001), while anti-CBir1 was more frequent in the younger children (66% vs 54%, p<0.05). Anti-CBir1 detected a significant number of children in both age groups who otherwise were serologically negative. Both age at diagnosis and site of CD involvement were independently associated with expression of ASCA and anti-CBir1. CONCLUSIONS Compared to children 8–15 yr of age at diagnosis, those 0–7 yr are more likely to express anti-CBir1 but only half as likely to express ASCA. These age-associated differences in antimicrobial seropositivity suggest that there may be different, and as yet unrecognized, genetic, immunologic and/or microbial factors leading to CD in the youngest children. PMID:19107777

  16. Is there a possible single mediator in modulating neuroendocrine-thymus interaction in ageing?

    PubMed

    Mocchegiani, Eugenio; Malavolta, Marco; Costarelli, Laura; Giacconi, Robertina; Piacenza, Francesco; Lattanzio, Fabrizia; Basso, Andrea

    2013-02-01

    The restoration of the thymic functions and the thymic re-growth may be achieved in old mice by some endocrinological (melatonin) or nutritional interventions (arginine or zinc), suggesting that the thymic involution in old age is a phenomenon secondary to age-related alterations occurring in neuroendocrine-thymus interactions. The targets for the thymic restoration may be hormone receptors and cytokines, strictly related to the presence of two nutritional factors, such as arginine and zinc, which are in turn essential for the efficiency of neuroendocrine-immune network both in ontogeny and ageing. The effect of melatonin is largely due to the presence of its specific receptors on cell membrane of thymocytes and Thymic Epithelial Cells (TECs). TECs synthesize thymulin peptide that is required for T-cell differentiation and maturation within the thymus gland. In this context, the role of zinc is pivotal because it is involved, through "zinc finger motifs", in the gene expression of melatonin receptors, in cell proliferation, apoptosis and thymulin reactivation. Zinc is also required for the biological action of arginine, via Nitric Oxide pathway. Therefore, the beneficial effect of melatonin or arginine on neuroendocrine-thymus interaction in ageing can also occur via a better zinc pool redistribution within the body where the capability of the zinc-binding proteins Metallothioneins (MT) in zinc release has a key role. These findings suggest that zinc, via MT buffering, can be a single mediator in modulating neuroendocrine-thymus interaction in ageing.

  17. Possible Mesozoic age of Ellenville Zn-Pb-Cu(Ag) deposit, Shawangunk Mountains, New York

    USGS Publications Warehouse

    Friedman, J.D.; Conrad, J.E.; McKee, E.H.; Mutschler, F.E.; Zartman, R.E.

    1994-01-01

    Ore textures, epithermal open-space filling of Permian structures of the Alleghanian orogeny, and largely postorogenic mineralization of the Ellenville, New York, composite Zn-Pb-Cu(Ag) vein system, provide permissive evidence for post-Permian mineralization. Isochron ages determined by 40Ar/39Ar laser-fusion techniques for K-bearing liquid inclusions in main-stage quartz from the Ellenville deposit additionally suggest a Mesozoic time of mineralization, associated with extensional formation of the Newark basin. The best 40Ar/39Ar total-fusion age range is 165 ?? 30 to 193 ?? 35 Ma. The Mesozoic 40Ar/39Ar age agrees with that of many other dated northern Appalachian Zn-Pb-Cu(Ag) deposits with near-matching lead isotope ratios, and adds new evidence of Jurassic tectonism and mineralization as an overprint to Late Paleozoic tectonism at least as far north as Ellenville (lat. 41??43???N). ?? 1994 Springer-Verlag.

  18. Retaining the wisdom: Academic nurse leaders' reflections on extending the working life of aging nurse faculty.

    PubMed

    Falk, Nancy L

    2014-01-01

    Aging nurse faculty members are vital human resources who serve as educators, researchers, and leaders within baccalaureate nursing (BSN) programs. On average, aging nurse faculty members are over 50 years of age and face key retirement decisions over the next decade. The purpose of this study was to begin to build substantive theory about academic nurse leaders' perceptions of extending the academic working life of aging nurse faculty members. Nine academic nurse leaders from BSN programs nationwide were interviewed in this grounded theory study. Data were analyzed using constant comparative analysis. Four categories emerged: valuing aging nurse faculty, enduring environmental challenges, recognizing stakeholder incongruence, and readjusting. Findings reveal that aging nurse faculty members are highly valued by academic nurse leaders, bringing wisdom, experience, and institutional, historical, and cultural awareness to their many roles. Yet, some aging nurse faculty fail to keep knowledge, skills, and teaching modes current, which is problematic given the multiple environmental challenges that academic nurse leaders face. Stakeholder incongruence arises as a mismatch between the needs of the BSN program and the skills and contributions of aging nurse faculty members. BSN programs, program leaders, and aging nurse faculty members can lessen incongruence by readjusting to address the pressures, tensions, and ongoing change. PMID:24503313

  19. Vegetation mapping using high resolution MSS (Multispectral Scanner) data: Canopy reflectance and shadow problems encountered and possible solutions

    SciTech Connect

    Jensen, J.R.; Hodgson, M.E.; Pinder, J.; Collins, B.S.; Mackey, H.E. Jr.

    1988-01-01

    High resolution Multispectral Scanner (MSS) data were acquired for an old field, successional habitat in South Carolina. The instrument used was a Daedalus Model DS-1268 having 1.5 x 1.5 m spatial resolution and 11 spectral bands. The goal was to map the vegetation of the study area and compute standing biomass. Upon examination of the MSS data, it became apparent that additional information would be required to accurately discriminate between the vegetation types because of (1) nonuniformity of canopy reflectance from individual trees due to sun angle and azimuth, and (2) shadows cast by trees. This paper describes the nature of the canopy reflectance problem, methods of removing the effects of shadows in high resolution MSS data, and the computation of biomass for the study area.

  20. Donor/Recipient Delta Age: A Possible Risk for Arterial Stenosis in Renal Transplantation

    PubMed Central

    Pallotti, Giovanni; Donati, Gabriele; Capelli, Irene; Baraldi, Olga; Comai, Giorgia; Agati, Patrizia; Nichelatti, Michele; Cianciolo, Giuseppe; La Manna, Gaetano

    2015-01-01

    Different arterial wall properties can significantly increase the risk of blood turbulent fluxes leading to complications such as atherosclerosis. Since the mechanical properties of arterial vessels are influenced by age, we investigated, in a retrospective study, the effects on renal artery stenosis of an age difference >15 years between donor and recipient in a cohort of 164 patients undergoing renal transplantation between 1981 and 1991. The age difference between donor and recipient was ≤15 years in 87 patients (53.0%) (Group A) and >15 years in 77 patients (47.0%) (Group B, p = ns). None of the Group A patients developed an anastomotic arterial stenosis, whereas 8/77 Group B patients (10.4%) had an anastomotic arterial stenosis (p < 0.001). This study shows that an age difference >15 years is significantly linked to the risk of developing arterial stenosis after renal transplantation. Indeed, different wall properties can significantly increase the risk of generation of blood turbulent fluxes and involve, in the arterial vessels, the development of complications such as atherosclerosis. PMID:26933444

  1. A drug-induced accelerated senescence (DIAS) is a possibility to study aging in time lapse.

    PubMed

    Alili, Lirija; Diekmann, Johanna; Giesen, Melanie; Holtkötter, Olaf; Brenneisen, Peter

    2014-06-01

    Currently, the oxidative stress (or free radical) theory of aging is the most popular explanation of how aging occurs at the molecular level. Accordingly, a stress-induced senescence-like phenotype of human dermal fibroblasts can be induced in vitro by the exposure of human diploid fibroblasts to subcytotoxic concentrations of hydrogen peroxide. However, several biomarkers of replicative senescence e.g. cell cycle arrest and enlarged morphology are abrogated 14 days after treatment, indicating that reactive oxygen species (ROS) rather acts as a trigger for short-term senescence (1-3 days) than being responsible for the maintenance of the senescence-like phenotype. Further, DNA-damaging factors are discussed resulting in a permanent senescent cell type. To induce long-term premature senescence and to understand the molecular alterations occurring during the aging process, we analyzed mitomycin C (MMC) as an alkylating DNA-damaging agent and ROS producer. Human dermal fibroblasts (HDF), used as model for skin aging, were exposed to non-cytotoxic concentrations of MMC and analyzed for potential markers of cellular aging, for example enlarged morphology, activity of senescence-associated-ß-galactosidase, cell cycle arrest, increased ROS production and MMP1-activity, which are well-documented for HDF in replicative senescence. Our data show that mitomycin C treatment results in a drug-induced accelerated senescence (DIAS) with long-term expression of senescence markers, demonstrating that a combination of different susceptibility factors, here ROS and DNA alkylation, are necessary to induce a permanent senescent cell type.

  2. Old Age Is a Part of Living: Student Reflections on Intergenerational Service-Learning

    ERIC Educational Resources Information Center

    Kalisch, Hilary R.; Coughlin, Deanna R.; Ballard, Sharon M.; Lamson, Angela

    2013-01-01

    Analysis of student journals examined the effect intergenerational service-learning had upon undergraduate students' attitudes and perceptions of older adults. Students (N = 102) engaged in 12 hours of service-learning with older adults that included writing structured reflection journals. Coding involved open, axial, and selective coding with…

  3. Adult Hippocampal Neurogenesis, Aging and Neurodegenerative Diseases: Possible Strategies to Prevent Cognitive Impairment.

    PubMed

    Vivar, Carmen

    2015-01-01

    The adult brain of humans and other mammals continuously generates new neurons throughout life. However, this neurogenic capacity is limited to two brain areas, the dentate gyrus (DG of the hippocampus and the subventricular zone (SVZ of the lateral ventricle. Although the DG generates new neurons, its neurogenic capacity declines with age and neurodegenerative diseases such as Alzheimer's disease (AD and Huntington's disease (HD. This review focuses on the role of newly-born neurons in cognitive processes, and discusses some of the strategies proposed in humans and animals to enhance neurogenesis and counteract age-related cognitive deficits, such as physical exercise and intake of natural products like omega-3 fatty acids, curcumin and flavanols. PMID:26059358

  4. The impact of sleep on age-related sarcopenia: Possible connections and clinical implications.

    PubMed

    Piovezan, Ronaldo D; Abucham, Julio; Dos Santos, Ronaldo Vagner Thomatieli; Mello, Marco Tulio; Tufik, Sergio; Poyares, Dalva

    2015-09-01

    Sarcopenia is a geriatric condition that comprises declined skeletal muscle mass, strength and function, leading to the risk of multiple adverse outcomes, including death. Its pathophysiology involves neuroendocrine and inflammatory factors, unfavorable nutritional habits and low physical activity. Sleep may play a role in muscle protein metabolism, although this hypothesis has not been studied extensively. Reductions in duration and quality of sleep and increases in prevalence of circadian rhythm and sleep disorders with age favor proteolysis, modify body composition and increase the risk of insulin resistance, all of which have been associated with sarcopenia. Data on the effects of age-related slow-wave sleep decline, circadian rhythm disruptions and obstructive sleep apnea (OSA) on hypothalamic-pituitary-adrenal (HPA), hypothalamic-pituitary-gonadal (HPG), somatotropic axes, and glucose metabolism indicate that sleep disorder interventions may affect muscle loss. Recent research associating OSA with the risk of conditions closely related to the sarcopenia process, such as frailty and sleep quality impairment, indirectly suggest that sleep can influence skeletal muscle decline in the elderly. Several protein synthesis and degradation pathways are mediated by growth hormone (GH), insulin-like growth factor-1 (IGF-1), testosterone, cortisol and insulin, which act on the cellular and molecular levels to increase or reestablish muscle fiber, strength and function. Age-related sleep problems potentially interfere intracellularly by inhibiting anabolic hormone cascades and enhancing catabolic pathways in the skeletal muscle. Specific physical exercises combined or not with nutritional recommendations are the current treatment options for sarcopenia. Clinical studies testing exogenous administration of anabolic hormones have not yielded adequate safety profiles. Therapeutic approaches targeting sleep disturbances to normalize circadian rhythms and sleep homeostasis may

  5. The impact of sleep on age-related sarcopenia: Possible connections and clinical implications.

    PubMed

    Piovezan, Ronaldo D; Abucham, Julio; Dos Santos, Ronaldo Vagner Thomatieli; Mello, Marco Tulio; Tufik, Sergio; Poyares, Dalva

    2015-09-01

    Sarcopenia is a geriatric condition that comprises declined skeletal muscle mass, strength and function, leading to the risk of multiple adverse outcomes, including death. Its pathophysiology involves neuroendocrine and inflammatory factors, unfavorable nutritional habits and low physical activity. Sleep may play a role in muscle protein metabolism, although this hypothesis has not been studied extensively. Reductions in duration and quality of sleep and increases in prevalence of circadian rhythm and sleep disorders with age favor proteolysis, modify body composition and increase the risk of insulin resistance, all of which have been associated with sarcopenia. Data on the effects of age-related slow-wave sleep decline, circadian rhythm disruptions and obstructive sleep apnea (OSA) on hypothalamic-pituitary-adrenal (HPA), hypothalamic-pituitary-gonadal (HPG), somatotropic axes, and glucose metabolism indicate that sleep disorder interventions may affect muscle loss. Recent research associating OSA with the risk of conditions closely related to the sarcopenia process, such as frailty and sleep quality impairment, indirectly suggest that sleep can influence skeletal muscle decline in the elderly. Several protein synthesis and degradation pathways are mediated by growth hormone (GH), insulin-like growth factor-1 (IGF-1), testosterone, cortisol and insulin, which act on the cellular and molecular levels to increase or reestablish muscle fiber, strength and function. Age-related sleep problems potentially interfere intracellularly by inhibiting anabolic hormone cascades and enhancing catabolic pathways in the skeletal muscle. Specific physical exercises combined or not with nutritional recommendations are the current treatment options for sarcopenia. Clinical studies testing exogenous administration of anabolic hormones have not yielded adequate safety profiles. Therapeutic approaches targeting sleep disturbances to normalize circadian rhythms and sleep homeostasis may

  6. Medical education in the digital age: personal reflection on a simulation fellowship.

    PubMed

    Simpson, Thomas

    2015-11-01

    Technology-advanced learning in healthcare has advanced dramatically in the last 10 years, with an increasing ability to recreate complex scenarios with clinical fidelity. Other technological developments can help to advance simulation-based training as part of a resilient approach to both common scenarios and rare events. In this article, I reflect on the some of the challenges of the developing paradigm of inter-professional high-fidelity simulation and the potential affordances of this modality.

  7. Medical education in the digital age: personal reflection on a simulation fellowship.

    PubMed

    Simpson, Thomas

    2015-11-01

    Technology-advanced learning in healthcare has advanced dramatically in the last 10 years, with an increasing ability to recreate complex scenarios with clinical fidelity. Other technological developments can help to advance simulation-based training as part of a resilient approach to both common scenarios and rare events. In this article, I reflect on the some of the challenges of the developing paradigm of inter-professional high-fidelity simulation and the potential affordances of this modality. PMID:26449923

  8. Evidence of a possible NNE-trending fault zone in the Summerville, South Carolina, area from shallow seismic reflection surveys

    SciTech Connect

    Marple, R.T.; Talwani, P. . Geology Dept.)

    1994-03-01

    Five high-resolution seismic-reflection surveys trending approximately WNW-ESE and totaling about 31 km were acquired in the Summerville, South Carolina, area. The surveys trend across the postulated Woodstock fault zone. These newly acquired data together with earlier data revealed the existence of an [approximately]50-km-long feature associated with gentle warping of the shallow sediments that lies along a recently described zone of river anomalies (ZRA). The first ([approximately]5.9-km-long) seismic reflection profile located about 14 km NNE of Summerville revealed that the J reflector (basalt) at about 670 m depth is offset about 30--40 m with the west side up. The overlying sediments displayed upwarping rather than brittle offset. A second ([approximately]6.7-km-long) survey located along interstate Highway 26 revealed as much as 30--40 m of upwarping of the sediments above about 450 m depth. A third ([approximately]7.3-km-long) profile acquired through the town of Summerville revealed four, [approximately]200--300 m wide, nearly vertical zones in which the reflectors are noncoherent. Away from these zones the reflectors are relatively flat and are slightly higher on the west side of each zone. The fourth (3-km-long) survey was located about 5 km SW of Middleton Gardens and indicated minor faulting at about 500 m depth. The fifth ([approximately]6.4-km-long) seismic survey acquired just north of Ravenel revealed an [approximately]0.5-km-wide zone in which the reflectors in the top 350 m displayed as much as 20 m of upwarping. On all the surveys, except for the first, the basalt was at too great a depth to be resolved.

  9. Researching to make a difference: possibilities for social science research in the age of AIDS.

    PubMed

    de Lange, Naydene

    2012-12-01

    HIV and AIDS is recognized as one of the most devastating pandemics of sub-Saharan Africa, and South Africa in particular, with adverse effect on individuals, families, schools, communities and society at large. Research is therefore required to provide a deeper understanding of the complexities of HIV and AIDS in order to mitigate the effect of the pandemic. Much of the excellent research that has been done has been undertaken within a positivist paradigm and has focused on the biomedical aspects of HIV and AIDS, as well as the social aspects of the pandemic. This theoretical position paper draws on various projects in the field of HIV and AIDS education in rural KwaZulu-Natal to argue that more social science research should be framed within a participatory research paradigm, foregrounding participant engagement and process, and which simultaneously has a "research-as-intervention" focus.Such research adheres to the requirement of knowledge production, but also engages the participants as knowledge producers who, through the research process, are enabled to shift towards taking up their own agency. Reflecting on the findings from the various projects suggests that visual participatory methodologies are particularly useful when working with marginalized persons whose voices are seldom heard especially when exploring topics which are difficult to discuss. Furthermore, it brings issues to the fore and opens up debate, while at the same time democratizing research and allowing universities to take up their social responsibility and to contribute towards making a difference in the communities they serve. PMID:23362539

  10. Researching to make a difference: possibilities for social science research in the age of AIDS.

    PubMed

    de Lange, Naydene

    2012-12-01

    HIV and AIDS is recognized as one of the most devastating pandemics of sub-Saharan Africa, and South Africa in particular, with adverse effect on individuals, families, schools, communities and society at large. Research is therefore required to provide a deeper understanding of the complexities of HIV and AIDS in order to mitigate the effect of the pandemic. Much of the excellent research that has been done has been undertaken within a positivist paradigm and has focused on the biomedical aspects of HIV and AIDS, as well as the social aspects of the pandemic. This theoretical position paper draws on various projects in the field of HIV and AIDS education in rural KwaZulu-Natal to argue that more social science research should be framed within a participatory research paradigm, foregrounding participant engagement and process, and which simultaneously has a "research-as-intervention" focus.Such research adheres to the requirement of knowledge production, but also engages the participants as knowledge producers who, through the research process, are enabled to shift towards taking up their own agency. Reflecting on the findings from the various projects suggests that visual participatory methodologies are particularly useful when working with marginalized persons whose voices are seldom heard especially when exploring topics which are difficult to discuss. Furthermore, it brings issues to the fore and opens up debate, while at the same time democratizing research and allowing universities to take up their social responsibility and to contribute towards making a difference in the communities they serve.

  11. Choosing among possible persons: The ethics of prenatal selection in the postgenomic age.

    PubMed

    Mauron, Alex

    2015-01-01

    The "spectre of eugenics" is often raised about various current reproductive practices that imply a form of choice between future possible persons. Some of these practices are linked to genetic technologies such as pre-implantation genetic diagnosis, others merely entail the choice of a procreator having specific traits, such as in artificial insemination with donor. The weight and limits of this reproof of eugenics are examined, with special attention to the conceptual problems resulting from confusing choices involving virtual persons with the selection of existing persons.

  12. Choosing among possible persons: The ethics of prenatal selection in the postgenomic age.

    PubMed

    Mauron, Alex

    2015-01-01

    The "spectre of eugenics" is often raised about various current reproductive practices that imply a form of choice between future possible persons. Some of these practices are linked to genetic technologies such as pre-implantation genetic diagnosis, others merely entail the choice of a procreator having specific traits, such as in artificial insemination with donor. The weight and limits of this reproof of eugenics are examined, with special attention to the conceptual problems resulting from confusing choices involving virtual persons with the selection of existing persons. PMID:26228932

  13. Bridging the Digital Divide: Reflections on "Teaching and Learning in the Digital Age"

    ERIC Educational Resources Information Center

    Pomerantz, Linda

    2001-01-01

    In 1998 the American Historical Association began an ambitious project, "Teaching and Learning in the Digital Age," designed to allow groups of historians in different parts of the country to experiment with the use of computer-based technologies to enhance the teaching of undergraduate survey courses. It aimed to enable these historians to…

  14. Transformations and Self-Discovery: Mature-Age Women's Reflections on Returning to University Study

    ERIC Educational Resources Information Center

    O'Shea, S.; Stone, C.

    2011-01-01

    Research has highlighted the challenges that women face as mature-age students in higher education. The challenges are particularly acute when a woman is the first in her family to go to university. Many women begin their journey as students with considerable self-doubt and lack of confidence. They may also face an ongoing struggle to find a way…

  15. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed

    Michel, Jean-Pierre

    2016-09-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published.

  16. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed Central

    2016-01-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published. PMID:27688858

  17. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed

    Michel, Jean-Pierre

    2016-09-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published. PMID:27688858

  18. Is It Possible to Delay or Prevent Age-Related Cognitive Decline?

    PubMed Central

    2016-01-01

    Already in the 90s, Khachaturian stated that postponing dementia onset by five years would decrease the prevalence of the late onset dementia by 50%. After two decades of lack of success in dementia drug discovery and development, and knowing that worldwide, currently 36 million patients have been diagnosed with Alzheimer's disease, a number that will double by 2030 and triple by 2050, the World Health Organization and the Alzheimer's Disease International declared that prevention of cognitive decline was a 'public health priority.' Numerous longitudinal studies and meta-analyses were conducted to analyze the risk and protective factors for dementia. Among the 93 identified risk factors, seven major modifiable ones should be considered: low education, sedentary lifestyle, midlife obesity, midlife smoking, hypertension, diabetes, and midlife depression. Three other important modifiable risk factors should also be added to this list: midlife hypercholesterolemia, late life atrial fibrillation, and chronic kidney disease. After their identification, numerous authors attempted to establish dementia risk scores; however, the proposed values were not convincing. Identifying the possible interventions, able to either postpone or delay dementia has been an important challenge. Observational studies focused on a single life-style intervention increased the global optimism concerning these possibilities. However, a recent extensive literature review of the randomized control trials (RCTs) conducted before 2014 yielded negative results. The first results of RCTs of multimodal interventions (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability, Multidomain Alzheimer Prevention Study, and Prediva) brought more optimism. Lastly, interventions targeting compounds of beta amyloid started in 2012 and no results have yet been published.

  19. Analogical reflection as a source for the science of life: Kant and the possibility of the biological sciences.

    PubMed

    Nassar, Dalia

    2016-08-01

    In contrast to the previously widespread view that Kant's work was largely in dialogue with the physical sciences, recent scholarship has highlighted Kant's interest in and contributions to the life sciences. Scholars are now investigating the extent to which Kant appealed to and incorporated insights from the life sciences and considering the ways he may have contributed to a new conception of living beings. The scholarship remains, however, divided in its interest: historians of science are concerned with the content of Kant's claims, and the ways in which they may or may not have contributed to the emerging science of life, while historians of philosophy focus on the systematic justifications for Kant's claims, e.g., the methodological and theoretical underpinnings of Kant's statement that living beings are mechanically inexplicable. My aim in this paper is to bring together these two strands of scholarship into dialogue by showing how Kant's methodological concerns (specifically, his notion of reflective judgment) contributed to his conception of living beings and to the ontological concern with life as a distinctive object of study. I argue that although Kant's explicit statement was that biology could not be a science, his implicit and more fundamental claim was that the study of living beings necessitates a distinctive mode of thought, a mode that is essentially analogical. I consider the implications of this view, and argue that it is by developing a new methodology for grasping organized beings that Kant makes his most important contribution to the new science of life.

  20. Analogical reflection as a source for the science of life: Kant and the possibility of the biological sciences.

    PubMed

    Nassar, Dalia

    2016-08-01

    In contrast to the previously widespread view that Kant's work was largely in dialogue with the physical sciences, recent scholarship has highlighted Kant's interest in and contributions to the life sciences. Scholars are now investigating the extent to which Kant appealed to and incorporated insights from the life sciences and considering the ways he may have contributed to a new conception of living beings. The scholarship remains, however, divided in its interest: historians of science are concerned with the content of Kant's claims, and the ways in which they may or may not have contributed to the emerging science of life, while historians of philosophy focus on the systematic justifications for Kant's claims, e.g., the methodological and theoretical underpinnings of Kant's statement that living beings are mechanically inexplicable. My aim in this paper is to bring together these two strands of scholarship into dialogue by showing how Kant's methodological concerns (specifically, his notion of reflective judgment) contributed to his conception of living beings and to the ontological concern with life as a distinctive object of study. I argue that although Kant's explicit statement was that biology could not be a science, his implicit and more fundamental claim was that the study of living beings necessitates a distinctive mode of thought, a mode that is essentially analogical. I consider the implications of this view, and argue that it is by developing a new methodology for grasping organized beings that Kant makes his most important contribution to the new science of life. PMID:27474186

  1. Arsenic Exposure and Immunotoxicity: a Review Including the Possible Influence of Age and Sex.

    PubMed

    Ferrario, Daniele; Gribaldo, Laura; Hartung, Thomas

    2016-03-01

    Increasing evidence suggests that inorganic arsenic, a major environmental pollutant, exerts immunosuppressive effects in epidemiological, in vitro, and animal models. The mechanisms, however, remain unclear, and little is known about variation in susceptibilities due to age and sex. We performed a review of the experimental and epidemiologic evidence on the association of arsenic exposure and immune diseases. The majority of the studies described arsenic as a potent immunosuppressive compound, though others have reported an increase in allergy and autoimmune diseases, suggesting that arsenic may also act as an immune system stimulator, depending on the dose or timing of exposure. Limited information, due to either the high concentrations of arsenic used in in vitro studies or the use of non-human data for predicting human risks, is available from experimental studies. Moreover, although there is emerging evidence that health effects of arsenic manifest differently between men and women, we found limited information on sex differences on the immunotoxic effects of arsenic. In conclusion, preliminary data show that chronic early-life exposure to arsenic might impair immune responses, potentially leading to increased risk of infections and inflammatory-like diseases during childhood and in adulthood. Further investigation to evaluate effects of arsenic exposure on the developing immune system of both sexes, particularly in human cells and using concentrations relevant to human exposure, should be a research priority.

  2. Awareness of the earth and possibilities for new science education in the Internet age.

    PubMed

    Takemura, S

    1999-01-01

    The internet as "the nervous system of global size" and multimedia technology have changed our global experience radically and suggests possibilities of entirely new approaches to the conventional education of sciences and the environment. They are not merely the changes where printed text books are converted into dynamic things with vivid appeal to our senses and information about the world's museums and art galleries, digitalized and shared by all. If the seismic activities occurring every day in various parts of the world can be seen in real form directly through the internet by all the people of the world, how will children's views of the earth change and how will their scientific understanding improved? If there was a system whereby one could monitor, in real time, how one member or others of the world net surf the global home pages, and if one could follow the "moving" process on the internet, children would certainly appreciate the presence of the internet as a global network of information. The web site "Sensorium" (http://www.sensorium.org) was created by us in an effort to put these live experiences of the internet into design. Sensorium is not a site merely to digitalize and list the existing knowledge and data. It is an experiment for the Digital Museum as a new "forum" where we may experience and share a moment. It is also an attempt to create tools for science and environment education which are only available on the network.

  3. Neural Activation During Submaximal Contractions Seems More Reflective of Neuromuscular Ageing than Maximal Voluntary Activation

    PubMed Central

    Scaglioni, Gil; Narici, Marco V.; Martin, Alain

    2016-01-01

    This study aimed at testing the hypothesis that differences in neural activation strategy during submaximal but not maximal plantarflexions exist between young and older men. Eleven young men (YM, 26 ± 4 years) and thirteen old men (OM, 76 ± 3 years) volunteered for the investigation. Maximal voluntary torque (MVT) was 38.2%, lower (p < 0.001) in OM than in YM, while voluntary activation was equivalent (~97%). The relationship between the interpolated twitch-torque and the voluntary torque (IT-VT relationship) was composite (curvilinear + exponential) for both age-groups. However, the OM showed accentuated concavity, as attested by the occurrence of the deviation from linearity at a lower contraction intensity (OM: 54.9 vs. YM: 71.9% MVT). In conclusion, ageing does not affect the capacity to fully activate the plantar flexors during maximal performances, but it alters the activation pattern for submaximal levels of effort. The greater age-related concavity of the IT-VT relationship suggests that, during submaximal contractions, OM need to reach a level of activation higher than YM to develop an equivalent relative torque. PMID:26941638

  4. Can injury prevention efforts go too far? Reflections on some possible implications of Vision Zero for road accident fatalities.

    PubMed

    Elvik, R

    1999-05-01

    The Swedish National Road Administration has launched a long term vision of a road transport system in which nobody is killed or sustains an injury resulting in permanent impairment (Vision Zero). This paper examines some possible implications of Vision Zero for traffic fatalities. The main points of the paper can be summarised as follows: An objective of eliminating traffic deaths can be interpreted as an application of a general principle of minimising mortality. Minimising overall mortality implies that a survival lottery must be introduced, at any rate as long as there is a shortage of organs for transplants. A survival lottery is a scheme in which people are drawn at random to sacrifice their life for the benefit of others. An objective of eliminating a certain cause of death, like traffic accidents, may be so expensive to realise that there is so much less resources available to control other causes of death that general mortality increases. Several analyses of the relationship between income per capita and general mortality based on Norwegian data document a negative relationship between income and mortality. The loss of income that induces an additional statistical death, due to economic inefficiency, is estimated to between 25 and 317 million NOK (3.8-47.5 million US dollars). These estimates are in line with those of most previous studies. No study of the relationship between income and mortality fully satisfies commonly used criteria of causality. However, the balance of evidence suggests that the relationship between income and mortality is a causal one. A hypothetical programme designed to implement Vision Zero for traffic fatalities was developed and its effects on the number of fatalities estimated. Implementing the whole programme could reduce the number of traffic deaths in Norway from about 300 per year to about 90 per year. Applying the lowest estimate of the income loss that induces an additional death (25 million NOK), it was estimated that

  5. Megalandslide in the Northern Caucasus foredeep (Uspenskoye, Russia): geomorphology, possible mechanism and age constraints

    NASA Astrophysics Data System (ADS)

    Pánek, T.; Hradecký, J.; Šilhán, K..; Strom, A. L.; Smolková, V.; Zerkal, O.

    2012-04-01

    Although worldwide datasets reveal that majority of giant landslides have occurred within the steepest portion of the Earth's landsurface, recent observations have brought evidence that some of the largest landslides originated in the low-relief landscapes and moved upon very gently inclined slip surfaces. Extremely large landslide with volume ~2.8 km3 was detected on the right bank of the Kuban river in the Northern Caucasus foredeep (Russian Federation). Megalandslide with gently inclined (<5°) slip surface originated within the low-gradient landscape formed by weak, nearly horizontally inclined clay-rich Miocene strata. Field analysis of numerous outcrops within the landslide body together with interpretations of DEM and satellite images revealed two stages of gravitational emplacement. Major phase was connected with rather catastrophic rotational blockslide transforming in the distal part to the earthflow. Secondary phase was attributed to the steepening of the landslide toe due to the lateral erosion of the Kuban river. As a consequence, multiply rotational collapse of the distal part of megalandslide took place. OSL and radiocarbon dating of both deformed soil and loess-like deposits overlying landslide body suggest possible formation of the Uspenskoye megalandslide between ~18-35 ka BP. Inferring trigger of the major megalandslide movement remains rather speculative, but we prefer palaeoseismic hypothesis in connection with rupture of some Late Quaternary fault in the vicinity of landslide area. Area of megalandslide is recently subject of intensive denudation marked by activity of numerous shallow landslides, gully erosion and dynamic aggradation (>2 m during last ~300 years) of material within valley floors.

  6. A megalandslide in the Northern Caucasus foredeep (Uspenskoye, Russia): Geomorphology, possible mechanism and age constraints

    NASA Astrophysics Data System (ADS)

    Pánek, Tomáš; Šilhán, Karel; Hradecký, Jan; Strom, Alexander; Smolková, Veronika; Zerkal, Oleg

    2012-12-01

    An extremely large landslide, ~ 2.8 km3 in volume and 32 km2 in area, has been detected on the right bank of the Kuban River in the Northern Caucasus foredeep (Russian Federation). The megalandslide has a very gently inclined slip surface (< 5°) and originated in a low-gradient landscape formed by weak, nearly horizontally inclined Miocene limestones overlying clay-rich strata. It is one of the largest documented slope failures in the world originating in low-gradient settings outside of high-relief mountain regions. Field analysis of 22 outcrops within the landslide body and interpretations of a 3″ SRTM digital elevation model and satellite images indicate at least two stages of emplacement. It started as a catastrophic rotational blockslide and turned into an earthflow in the distal part of the landslide. The secondary phase is attributed to a steepening of the landslide toe due to lateral erosion of the Kuban River. As a consequence, multiple rotational collapses of the distal part of the megalandslide occurred. OSL and AMS radiocarbon dating of deformed soil and loess overlying the landslide body suggest possible formation of the megalandslide between ~ 13 and 35 ka BP. Although the trigger of the megalandslide is difficult to establish, we hypothesise that during the slightly moister interval of the Last Glacial, it may have been triggered by an earthquake associated with the rupture of the Late Quaternary Kazminskiy Fault nearby. Fragmented and weakened material from the megalandslide has recently been subjected to intensive denudation by numerous shallow landslides, gully erosion and subsequent aggradation of material on valley floors.

  7. Attenuated total reflectance fourier transform infrared analysis of fly ash geopolymer gel aging.

    PubMed

    Rees, Catherine A; Provis, John L; Lukey, Grant C; van Deventer, Jannie S J

    2007-07-17

    Structural changes in fly ash geopolymers activated with different sodium hydroxide and silicate concentrations are investigated using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy over a period of 200 days. A strong correlation is found between the concentration of silicate monomer in the activating solution and the position of the main Si-O-T stretching band in the FTIR spectrum, which gives an indication of the relative changes in the gel Si/Al ratio. The FTIR spectra of geopolymer samples with activating solution concentrations of up to 1.2 M SiO2 indicate that an Al-rich gel forms before the final gel composition is reached. The time required for the system to reach a steady gel composition depends on the silicate activating solution concentration and speciation. Geopolymers activated with solutions containing predominantly high-order silicate species rapidly reach a steady gel composition without first forming an Al-rich gel. A minimum silicate monomer concentration of approximately 0.6 M is required to shift the geopolymer synthesis mechanism from hydroxide activation to silicate activation. Silicate speciation in the activating solutions also affects zeolite formation and geopolymer microstructures, with a more homogeneous microstructure and less zeolite formation observed at a higher SiO2 content.

  8. Transfer of Nature of Science Understandings into Similar Contexts: Promises and Possibilities of an Explicit Reflective Approach

    NASA Astrophysics Data System (ADS)

    Khishfe, Rola

    2013-11-01

    The purpose of this study was to (a) investigate the effectiveness of explicit nature of science (NOS) instruction in the context of controversial socioscientific issues and (b) explore whether the transfer of acquired NOS understandings, which were explicitly taught in the context of one socioscientific context, into other similar contexts (familiar and unfamiliar) was possible. Participants were 10th grade students in two intact sections at one high school. The treatment involved teaching a six-week unit about genetic engineering. For one group (non-NOS group), there was no explicit instruction about NOS. For the other group (NOS group), explicit instruction about three NOS aspects (subjective, empirical, and tentative) was dispersed across the genetic engineering unit. A questionnaire including two open-ended scenarios, in conjunction with semi-structured interviews, was used to assess the change in participants' understandings of NOS and their ability to transfer their acquired understandings into similar contexts. The first scenario involved a familiar context about genetically modified food and the second one focused on an unfamiliar context about water fluoridation. Results showed no improvement in NOS understandings of participants in the non-NOS group in relation to the familiar and unfamiliar contexts. On the other hand, there was a general improvement in the NOS understandings of participants in the NOS group in relation to both the familiar and unfamiliar contexts. Implications about the transfer of participants' acquired NOS understandings on the basis of the distance between the context of learning and that of application are highlighted and discussed in link with the classroom learning environment.

  9. U-Pb Detrital Zircon Ages from Sarawak: Changes in Provenance Reflecting the Tectonic Evolution of Southeast Asia

    NASA Astrophysics Data System (ADS)

    Breitfeld, H. T.; Galin, T.; Hall, R.

    2014-12-01

    Sarawak is located on the northern edge of Sundaland in NW Borneo. Five sedimentary basins are distinguished with ages from Triassic to Cenozoic. New light mineral, heavy mineral and U-Pb detrital zircon ages show differences in provenance reflecting the tectonic evolution of the region. The oldest clastic sediments are Triassic of the Sadong-Kuching Basin and were sourced by a Carnian to Norian volcanic arc and erosion of Cathaysian rocks containing zircons of Paleoproterozoic age. Sandstones of the Upper Jurassic to Cretaceous Bau-Pedawan Basin have distinctive zircon populations indicating a major change of tectonic setting, including initiation of subduction below present-day West Sarawak in the Late Jurassic. A wide range of inherited zircon ages indicates various Cathaysian fragments as major source areas and the arrival of the SW Borneo Block following subduction beneath the Schwaner Mountains in the early Late Cretaceous. After collision of the SW Borneo Block and the microcontinental fragments with Sundaland in the early Late Cretaceous, deep marine sedimentation (Pedawan Formation) ceased, and there was uplift forming the regional Pedawan-Kayan unconformity. Two episodes of extension were responsible for basin development on land from the latest Cretaceous onwards, probably in a strike-slip setting. The first episode formed the Kayan Basin in the Latest Cretaceous (Maastrichtian) to Early Paleocene, and the second formed the Ketungau Basin and the Penrissen Sandstone in the Middle to Late Eocene. Zircons indicate nearby volcanic activity throughout the Early Cenozoic in NW Borneo. Inherited zircon ages indicate an alternation between Borneo and Tin Belt source rocks. A large deep marine basin, the Rajang Basin, formed north of the Lupar Line fault. Zircons from sediments of the Rajang Basin indicate they are of similar age and provenance as the contemporaneous terrestrial sediments to the south suggesting a narrow steep continental Sundaland margin at the

  10. Three-dimensional structure of axonal mitochondria reflects the age of drosophila☆

    PubMed Central

    Zhu, Honglian; Sun, Xiaojiang

    2013-01-01

    This study aimed to reconstruct a three-dimensional map of axonal mitochondria using Fiji and Neurolucida software, and to observe directly the morphology and distribution of mitochondria in axons of motor neurons in dorsal longitudinal flight muscles of drosophila aged 5 days and 20 days, using electron microscopy. Results indicated that there was no difference in the total area and volume of mitochondria between 5-day-old drosophila and 20-day-old drosophila in all sections, but the ratio of mitochondrial total areas to axon total areas, as well as mitochondrial density of 20-day-old drosophila, was lower than that of 5-day-old drosophila. The number of mitochondria, whose volume was less than 1 000 000 μm3, and between 1 000 000 μm3 and 10 000 000 μm3, was higher in 20-day-old drosophila than that in 5-day-old drosophila. The number of mitochondria with a volume between 1 000 000 μm3 and 100 000 000 μm3 was apparently higher than those with a volume less than 1 000 000 μm3 or larger than 100 000 000 μm3. In addition, the number of mitochondria with a volume more than 100 000 000 μm3 was small; however, the volume was nearly 70% of the total volume in both 5-day-old and 20-day-old drosophila. In contrast, the number of mitochondria with a volume between 1 000 000 μm3 and 10 000 000 μm3 was large, but the volume was less than 30% of the total volume. These experimental findings suggest that changes in mitochondrial morphology and number in motor neurons from the dorsal longitudinal muscle of drosophila are present during different ages. PMID:25206706

  11. Possible effects of anthropogenically-increased CO2 on the dynamics of climate - Implications for ice age cycles

    NASA Technical Reports Server (NTRS)

    Saltzman, Barry; Maasch, Kirk A.; Verbitsky, Mikhail YA.

    1993-01-01

    A dynamical model, developed to account for the observed major variations of global ice mass and atmospheric CO2 during the late Cenozoic, is used to provide a quantitative demonstration of the possibility that the anthropogenically-forced increase of atmospheric CO2, if maintained over a long period of time (perhaps by tectonic forcing), could displace the climatic system from an unstable regime of oscillating ice ages into a more stable regime representative of the pre-Pleistocene. This stable regime is characterized by orbitally-forced oscillations that are of much weaker amplitude than prevailed during the Pleistocene.

  12. Multiple imputation for national public-use datasets and its possible application for gestational age in United States Natality files.

    PubMed

    Parker, Jennifer D; Schenker, Nathaniel

    2007-09-01

    Multiple imputation (MI) is a technique that can be used for handling missing data in a public-use dataset. With MI, two or more completed versions of the dataset are created, containing possibly different but reasonable replacements for the missing data. Users analyse the completed datasets separately with standard techniques and then combine the results using simple formulae in a way that allows the extra uncertainty due to missing data to be assessed. An advantage of this approach is that the resulting public-use data can be analysed by a variety of users for a variety of purposes, without each user needing to devise a method to deal with the missing data. A recent example for a large public-use dataset is the MI of the family income and personal earnings variables in the National Health Interview Survey. We propose an approach to utilise MI to handle the problems of missing gestational ages and implausible birthweight-gestational age combinations in national vital statistics datasets. This paper describes MI and gives examples of MI for public-use datasets, summarises methods that have been used for identifying implausible gestational age values on birth records, and combines these ideas by setting forth scenarios for identifying and then imputing missing and implausible gestational age values multiple times. Because missing and implausible gestational age values are not missing completely at random, using multiple imputations and, thus, incorporating both the existing relationships among the variables and the uncertainty added from the imputation, may lead to more valid inferences in some analytical studies than simply excluding birth records with inadequate data.

  13. Symmetry of the face in old age reflects childhood social status.

    PubMed

    Hope, David; Bates, Timothy; Penke, Lars; Gow, Alan J; Starr, John M; Deary, Ian J

    2013-03-01

    The association of socioeconomic status (SES) with a range of lifecourse outcomes is robust, but the causes of these associations are not well understood. Research on the developmental origins of health and disease has led to the hypothesis that early developmental disturbance might permanently affect the lifecourse, accounting for some of the burden of chronic diseases such as coronary heart disease. Here we assessed developmental disturbance using bodily and facial symmetry and examined its association with socioeconomic status (SES) in childhood, and attained status at midlife. Symmetry was measured at ages 83 (facial symmetry) and 87 (bodily symmetry) in a sample of 292 individuals from the Lothian Birth Cohort 1921 (LBC1921). Structural equation models indicated that poorer SES during early development was significantly associated with lower facial symmetry (standardized path coefficient -.25, p=.03). By contrast, midlife SES was not significantly associated with symmetry. The relationship was stronger in men (-.44, p=.03) than in women (-.12, p=.37), and the effect sizes were significantly different in magnitude (p=.004). These findings suggest that SES in early life (but not later in life) is associated with developmental disturbances. Facial symmetry appears to provide an effective record of early perturbations, whereas bodily symmetry seems relatively imperturbable. As bodily and facial symmetries were sensitive to different influences, they should not be treated as interchangeable. However, markers of childhood disturbance remain many decades later, suggesting that early development may account in part for associations between SES and health through the lifecourse. Future research should clarify which elements of the environment cause these perturbations.

  14. Effects of leaf age within growth stages of pepper and sorghum plants on leaf thickness, water, chlorophyll, and light reflectance. [in spectral vegetation discrimination

    NASA Technical Reports Server (NTRS)

    Gausman, H. W.; Cardenas, R.; Berumen, A.

    1974-01-01

    Pepper and sorghum plants (characterized by porous and compact leaf mesophylls, respectively) were used to study the influence of leaf age on light reflectance. Measurements were limited to the upper five nodal positions within each growth stage, since upper leaves make up most of the reflectance surfaces remotely sensed. The increase in leaf thickness and water content with increasing leaf age was taken into consideration, since each of these factors affects the reflectance as well as the selection of spectral wavelength intervals for optimum discrimination of vegetation.

  15. Modification of DNA by reducing sugars: a possible mechanism for nucleic acid aging and age-related dysfunction in gene expression.

    PubMed

    Bucala, R; Model, P; Cerami, A

    1984-01-01

    Reducing sugars react nonenzymatically with protein amino groups to initiate a process called nonenzymatic browning. Long-lived proteins, such as collagen and the lens crystallins, accumulate sufficient modification in vivo that they acquire many of the chemical properties characteristic of aged proteins. We have obtained evidence that nucleic acids also can undergo nonenzymatic modification by sugars. Incubation of DNA or nucleotides with glucose 6-phosphate (Glc-6-P) produces spectral changes similar to those described for nonenzymatic browning proteins. The occurrence of chemical modification was verified by measuring the transfection efficiency of viral DNA after incubation with glucose and Glc-6-P. A loss of transfection potential occurred that was first order with respect to time and sugar concentration. The rate of inactivation by Glc-6-P was 25 times that of glucose; 8 days of incubation with 150 mM Glc-6-P decreased transfection by 4 orders of magnitude. Glc-6-P also produced strand scission in a time- and concentration-dependent manner. We conclude that glucose, Glc-6-P, and possibly other sugars can react with DNA to produce significant structural and biological alterations. Since nucleic acids are long-lived molecules in the resting cell, the accumulation of these addition products might be a mechanism for the decreased genetic viability characteristic of the aged organism. PMID:6582469

  16. Implementing preventive iron-folic acid supplementation among women of reproductive age in some Western Pacific countries: possibilities and challenges.

    PubMed

    Smitasiri, Suttilak; Solon, Florentino S

    2005-12-01

    Lack of effective implementation mechanisms is identified as a major obstacle in the prevention and control of iron-deficiency anemia. This paper discusses experiences gained from implementing iron-folic acid supplementation in the Philippines, Vietnam, and Cambodia. The understanding of contextual elements is proposed as a foundation for planning interventions. Moreover, it is suggested that a social marketing framework should provide a way of thinking about how to influence related behaviors. The application of a social marketing framework applied using a "5 P's" approach: public relations and collaboration, product, price, place, and promotion, is described, as well as enabling factors (possibilities) and inhibiting factors (challenges) of this approach. Although a program to improve iron nutrition among women of reproductive age may not be simple to implement, it is essential to enhancing health, human development, and economic advancement in developing countries.

  17. Reflection and reflective practice.

    PubMed

    Schutz, Sue

    2007-09-01

    Reflection is an approach to the generation of understanding about practice that has become a largely accepted part of nursing education at both undergraduate and post-qualifying levels. It is also increasingly common now for healthcare professionals to use reflection in their practice communities as a part of their daily professional work. The literature is replete with accounts of the possible benefits to practitioners and clients of using reflection in practice, yet this amounts to a rather scant evidence base. For community nurses there are several challenges in the practical application of reflective practice, but these are not insurmountable. Issues such as lone-working and geographical distance may be a challenge. There are some key skills that will help public health and community practitioners get started in reflection and some important issues that should be addressed before beginning. Reflective practice has, however, the potential to help practitioners in all fields unlock the tacit knowledge and understanding that they have of their practice and use this to generate knowledge for future practice.

  18. Tackling the aging process with bio-molecules: a possible role for caloric restriction, food-derived nutrients, vitamins, amino acids, peptides, and minerals.

    PubMed

    Dabhade, Prachi; Kotwal, Swati

    2013-01-01

    Aging is a multifactorial process leading to general deterioration in many tissues and organs, accompanied by an increased incidence and severity of a wide variety of chronic, incurable, and often fatal diseases. A possibility of slowing down the aging process and improving the quality of life in old age by nutritional intervention has renewed the interest of the scientific world in anti-aging therapies. These include potential dietary interventions, adherence to nutrition, hormonal and cell-based therapies, genetic manipulations, and anti-aging supplements or nutrients. This review addresses strategies to slow the aging process by caloric restriction and the use of nutritional supplements.

  19. Red tide detection by means of peak shift of remote sensing reflectance and possibility of red tide detection with polarized radiance measurements

    NASA Astrophysics Data System (ADS)

    Arai, Kohei; Terayama, Yasunori

    2010-11-01

    A method for detection of red tide by means of remote sensing reflectance peak shift is proposed together with suspended solid influence eliminations. Although remote sensing reflectance peak is situated at around 550nm for sea water without suffered from red tide, the peak is shifted to the longer wavelength when sea water is suffered from red tide. Based on this fact, it is capable to detect red tide using high wavelength resolution of spectral-radiometers. The proposed system uses web camera with band-pass filter on the optics surface. Acquired imagery data can be transmitted through wireless LAN to Internet terminal and can be archived in server through Internet. Validity of the proposed method is confirmed with the system deployed in Ariake Sea which is situated in northern Kyushu, Japan. Also a method for red tide detection with satellite imagery data is attempted with suspended solid influence eliminations. Furthermore, a possibility of red tide detection with polarized radiance measurements is discussed through polarization camera derived sue surface imagery data, in particular, for non-spherical shape of red tide.

  20. Study of the possibility of increasing the probing depth by the method of reflection confocal microscopy upon immersion clearing of near-surface human skin layers

    SciTech Connect

    Meglinskii, I V; Bashkatov, A N; Genina, Elina A; Tuchin, Valerii V; Churmakov, D Yu

    2002-10-31

    The possibility of increasing the human-skin probing depth by the method of reflection confocal microscopy (RCM) upon decreasing the amplitude of spatial fluctuations of the refractive index of the upper skin layers is considered. A change in the probing depth is estimated by analysing the spatial distribution of the probability density of the effective optical paths of detected photons calculated by the Monte Carlo method. The results of the numerical simulation are interpreted within the framework of the possible application of RCM to the study of the human skin exposed to an immersion liquid compatible to it. A diffusion of the immersion agent into the skin depth involves the equalising of the refractive indices of the structural elements of near-surface skin layers, which in turn causes a decrease in the scattering intensity and a certain increase in the transparency of the upper tissue layers. It is shown that a decrease in the light scattering in the near-surface skin layers leads to a significant increase in the probing depth obtained with the RCM technique.

  1. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001-2009 MISR imagery of Borneo

    NASA Astrophysics Data System (ADS)

    Zender, C. S.; Krolewski, A. G.; Tosca, M. G.; Randerson, J. T.

    2011-11-01

    Land clearing for crops and plantations and grazing results in anthropogenic burning of tropical forests and peatlands in Indonesia, where images of fire-generated aerosol plumes have been captured by the Multi-angle Imaging SpectroRadiometer (MISR) since 2001. Our modeling studies show this smoke increases atmospheric heating, and reduces regional SST and dry-season precipitation, causing a potential feedback that increases drought-stress and air quality problems during El Niño years. Here we analyze the size, shape, optical properties, and age of fire-generated plumes in Borneo from 2001-2009. Most smoke flows with the prevailing southeasterly surface winds at 3-4 m s-1, and forms ovoid plumes whose mean length, height, and cross-plume width are 41 ± 1.4 (mean ± std. error) km, 708 ± 13 m, and 27 ± 0.75% of the plume length, respectively. Borneo smoke plume heights are similar to previously reported plume heights, yet Borneo plumes are nearly three times longer than previously studied plumes, possibly due to more persistent fires and greater fuel loads in peatlands than in other tropical forests. Plume area (median 169 ± 15 km2) varies exponentially with length, though for most plumes a linear relation provides a good approximation. The MISR-estimated plume optical properties involve greater uncertainties than the geometric properties, and show patterns consistent with smoke aging. Optical depth increases by 15-25% in the down-plume direction, consistent with hygroscopic growth and nucleation overwhelming the effects of particle dispersion. Both particle single-scattering albedo and top-of-atmosphere albedo peak about halfway down-plume, at values about 3% and 10% greater than at the origin, respectively. The initially oblong plumes become brighter and more circular with time, increasingly resembling smoke clouds. Wind speed does not explain a significant fraction of the variation in plume geometry. We provide a parameterization of plume shape that can help

  2. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001-2009 MISR imagery of Borneo

    NASA Astrophysics Data System (ADS)

    Zender, C. S.; Krolewski, A. G.; Tosca, M. G.; Randerson, J. T.

    2012-04-01

    Land clearing for crops, plantations and grazing results in anthropogenic burning of tropical forests and peatlands in Indonesia, where images of fire-generated aerosol plumes have been captured by the Multi-angle Imaging SpectroRadiometer (MISR) since 2001. Here we analyze the size, shape, optical properties, and age of distinct fire-generated plumes in Borneo from 2001-2009. The local MISR overpass at 10:30 a.m. misses the afternoon peak of Borneo fire emissions, and may preferentially sample longer plumes from persistent fires burning overnight. Typically the smoke flows with the prevailing southeasterly surface winds at 3-4 m s-1, and forms ovoid plumes whose mean length, height, and cross-plume width are 41 km, 708 m, and 27% of the plume length, respectively. 50% of these plumes have length between 24 and 50 km, height between 523 and 993 m and width between 18% and 30% of plume length. Length and cross-plume width are lognormally distributed, while height follows a normal distribution. Borneo smoke plume heights are similar to previously reported plume heights, yet Borneo plumes are on average nearly three times longer than previously studied plumes. This could be due to sampling or to more persistent fires and greater fuel loads in peatlands than in other tropical forests. Plume area (median 169 km2, with 25th and 75th percentiles at 99 km2 and 304 km2, respectively) varies exponentially with length, though for most plumes a linear relation provides a good approximation. The MISR-estimated plume optical properties involve greater uncertainties than the geometric properties, and show patterns consistent with smoke aging. Optical depth increases by 15-25% in the down-plume direction, consistent with hygroscopic growth and nucleation overwhelming the effects of particle dispersion. Both particle single-scattering albedo and top-of-atmosphere reflectance peak about halfway down-plume, at values about 3% and 10% greater than at the origin, respectively. The

  3. The Primacy of Child-Directed Pretend Play on Cognitive Competence in a Mixed-Age Environment: Possible Interpretations

    ERIC Educational Resources Information Center

    Gmitrova, Vlasta; Gmitrov, Juraj

    2004-01-01

    The goal was to study the impact of a teacher-directed and a child-directed pretend play on cognitive performance in a mixed-age environment. Twenty-six observations were performed on fifty-one kindergarten children with a mean age of 4.6 years (age span from three to six years) in two mixed-aged classrooms. Data were collected regarding…

  4. Microglial AGE-albumin is critical for neuronal death in Parkinson’s disease: a possible implication for theranostics

    PubMed Central

    Bayarsaikhan, Enkhjargal; Bayarsaikhan, Delger; Lee, Jaesuk; Son, Myeongjoo; Oh, Seyeon; Moon, Jeongsik; Park, Hye-Jeong; Roshini, Arivazhagan; Kim, Seung U; Song, Byoung-Joon; Jo, Seung-Mook; Byun, Kyunghee; Lee, Bonghee

    2015-01-01

    Advanced glycation end products (AGEs) are known to play an important role in the pathogenesis of neurodegenerative diseases, including Parkinson’s disease (PD), by inducing protein aggregation and cross-link, formation of Lewy body, and neuronal death. In this study, we observed that AGE-albumin, the most abundant AGE product in the human PD brain, is synthesized in activated microglial cells and accumulates in the extracellular space. AGE-albumin synthesis in human-activated microglial cells is distinctly inhibited by ascorbic acid and cytochalasin treatment. Accumulated AGE-albumin upregulates the receptor to AGE, leading to apoptosis of human primary dopamine (DA) neurons. In animal experiments, we observed reduced DA neuronal cell death by treatment with soluble receptor to AGE. Our study provides evidence that activated microglial cells are one of the main contributors in AGE-albumin accumulation, deleterious to DA neurons in human and animal PD brains. Finally, activated microglial AGE-albumin could be used as a diagnostic and therapeutic biomarker with high sensitivity for neurodegenerative disorders, including PD. PMID:27601894

  5. Microglial AGE-albumin is critical for neuronal death in Parkinson’s disease: a possible implication for theranostics

    PubMed Central

    Bayarsaikhan, Enkhjargal; Bayarsaikhan, Delger; Lee, Jaesuk; Son, Myeongjoo; Oh, Seyeon; Moon, Jeongsik; Park, Hye-Jeong; Roshini, Arivazhagan; Kim, Seung U; Song, Byoung-Joon; Jo, Seung-Mook; Byun, Kyunghee; Lee, Bonghee

    2015-01-01

    Advanced glycation end products (AGEs) are known to play an important role in the pathogenesis of neurodegenerative diseases, including Parkinson’s disease (PD), by inducing protein aggregation and cross-link, formation of Lewy body, and neuronal death. In this study, we observed that AGE-albumin, the most abundant AGE product in the human PD brain, is synthesized in activated microglial cells and accumulates in the extracellular space. AGE-albumin synthesis in human-activated microglial cells is distinctly inhibited by ascorbic acid and cytochalasin treatment. Accumulated AGE-albumin upregulates the receptor to AGE, leading to apoptosis of human primary dopamine (DA) neurons. In animal experiments, we observed reduced DA neuronal cell death by treatment with soluble receptor to AGE. Our study provides evidence that activated microglial cells are one of the main contributors in AGE-albumin accumulation, deleterious to DA neurons in human and animal PD brains. Finally, activated microglial AGE-albumin could be used as a diagnostic and therapeutic biomarker with high sensitivity for neurodegenerative disorders, including PD.

  6. Windows on Martian dynamo history: electron reflection (ER) magnetic signatures and crater retention ages of basins and volcanoes

    NASA Astrophysics Data System (ADS)

    Lillis, R. J.; Frey, H. V.; Manga, M.; Halekas, J. S.; Mitchell, D. L.; Lin, R. P.

    2006-12-01

    A picture continues to emerge of a Martian dynamo that began extremely early in the planet's history. After reversing polarity at least once and possibly varying significantly in strength, it permanently ceased operating prior to 4 billion years ago (using the Hartmann-Neukum chronology), when the core could no longer sustain the required convective motion. By combining ER magnetometry and MOLA topography, we use the derived magnetic signatures and crater retention ages (CRAs) of large basins and volcanoes to constrain the ambient magnetic conditions present during their formation. Here we present results that support the above picture; in particular case studies involving several large visible and buried basins and highland volcanoes, implying that Mars' last dynamo activity likely ceased prior to 4.07 ± 0.04 Gyr ago and later than 4.15 ± 0.05 Gyr ago and that this cessation was, within uncertainties, coincident with the formation of the 3 giant northern lowland basins Acidalia, Chryse and Utopia. We also present a statistical study of the magnetic signatures and CRAs of the ~500 largest basins on Mars which tentatively suggests that the dynamo may have weakened considerably for a period during its active lifetime.

  7. Identification of possible recent water/lava source fissures in the Cerberus Plains: stratigraphic and crater count age constraints

    NASA Astrophysics Data System (ADS)

    Thomas, Rebecca J.

    2013-04-01

    The Cerberus plains are one of the youngest surfaces on Mars. They are thought to have been formed by lava and/or water flows, but there is considerable debate regarding the source of this material. Much of the material forming the western plains, including the Athabasca Valles outflow channels, appears to have flowed from the region of the Cerberus Fossae graben system [1,2,3] and limited areas forming the eastern plains may have been erupted by low shield volcanoes [4,5]. However, flow of material from west to east is obstructed by a ridge centred on 157°E, 7°N and, prior to this study, vents which might be the source of fluid of a low enough viscosity to form the majority of the flat eastern plains had not been identified. We studied new HiRISE (25cm/px, High Resolution Science Imaging Experiment) images of the ridge between the east and west plains and observed possible source vents for this material: the ridge is cut by a series of pits and fissures which lie at the heads of flows and channels extending towards the surrounding plains. In order to establish the stratigraphic relationships between the vents and plains, this study produced large scale geomorphological maps based on the HiRISE images. The mapping showed that both incised channels and leveed flows extend onto the plain to the south of the ridge and that these were the final phase of plains-forming activity in that region. Conversely, to the north, ridge-sourced deposits only form the plains surface close to the ridge - beyond that, they are overlain by large-scale regional flows that appear to have originated from the direction of Athabasca Valles. In the southeast, a large-scale flow which does not emanate from this ridge forms the plains surface, but there is evidence that the youngest outflow activity from the ridge was contemporaneous with emplacement of this unit. We also performed crater counts to age-date the surfaces and these indicate that plains-forming and ridge-sourced units are of a

  8. Possible Influences of Arabic-Islamic Culture on the Reflective Practices Proposed for an Education Degree at the Higher Colleges of Technology in the United Arab Emirates

    ERIC Educational Resources Information Center

    Richardson, Patricia M.

    2004-01-01

    This article critically examines the compatibility of United Arab Emirates culture and values with the assumptions of reflective practice currently being written into a new teacher education degree programme. The curriculum that is being developed relies heavily on the notions of reflective practice as a method of professional development. The…

  9. Soiling of building envelope surfaces and its effect on solar reflectance – Part II: Development of an accelerated aging method for roofing materials

    SciTech Connect

    Sleiman, Mohamad; Kirchstetter, Thomas W.; Berdahl, Paul; Gilbert, Haley E.; Quelen, Sarah; Marlot, Lea; Preble, Chelsea V.; Chen, Sharon; Montalbano, Amandine; Rosseler, Olivier; Akbari, Hashem; Levinson, Ronnen; Destaillats, Hugo

    2014-01-09

    Highly reflective roofs can decrease the energy required for building air conditioning, help mitigate the urban heat island effect, and slow global warming. However, these benefits are diminished by soiling and weathering processes that reduce the solar reflectance of most roofing materials. Soiling results from the deposition of atmospheric particulate matter and the growth of microorganisms, each of which absorb sunlight. Weathering of materials occurs with exposure to water, sunlight, and high temperatures. This study developed an accelerated aging method that incorporates features of soiling and weathering. The method sprays a calibrated aqueous soiling mixture of dust minerals, black carbon, humic acid, and salts onto preconditioned coupons of roofing materials, then subjects the soiled coupons to cycles of ultraviolet radiation, heat and water in a commercial weatherometer. Three soiling mixtures were optimized to reproduce the site-specific solar spectral reflectance features of roofing products exposed for 3 years in a hot and humid climate (Miami, Florida); a hot and dry climate (Phoenix, Arizona); and a polluted atmosphere in a temperate climate (Cleveland, Ohio). A fourth mixture was designed to reproduce the three-site average values of solar reflectance and thermal emittance attained after 3 years of natural exposure, which the Cool Roof Rating Council (CRRC) uses to rate roofing products sold in the US. This accelerated aging method was applied to 25 products₋single ply membranes, factory and field applied coatings, tiles, modified bitumen cap sheets, and asphalt shingles₋and reproduced in 3 days the CRRC's 3-year aged values of solar reflectance. In conclusion, this accelerated aging method can be used to speed the evaluation and rating of new cool roofing materials.

  10. Defective stretch-induced release of atrial natriuretic peptide from aging hypertensive rat heart: possible role of phosphatidylinositol pathway.

    PubMed

    Brunner, F; Mouton, R; Lochner, A; Opie, L H

    1995-01-01

    Because the phosphatidylinositol pathway may be part of the signaling system associated with stretch-induced release of atrial natriuretic peptide (ANP), we tested the hypothesis that formation of the intermediate inositol-1,4,5-trisphosphate (IP3) is impaired when ANP release is decreased in response to atrial stretch in hearts from aging genetically hypertensive (GH) rats. Immunoreactive ANP release into the coronary effluent and IP3 levels were studied in cardiac tissues of isolated perfused hearts from normotensive control (WAG) or GH rats aged 4, 11, or 16 months. Left atria were repeatedly distended and released with a latex balloon. ANP was measured in coronary effluent, and IP3 was measured in cardiac tissues. In all age groups, stretch and relief of stretch evoked considerably less ANP release in spontaneously beating hearts from GH than from WAG rats. Hearts from GH rats aged 16 months released no ANP, but electrical pacing restored some stretch-induced ANP secretion. With repeated stretch and release of stretch of the left atrium for 2 min, IP3 levels increased in left atrial tissue in WAG but not in GH hearts of all age groups. IP3 levels in (unstretched) left ventricles were much lower than in left atria and were unaltered by atrial stretch. In aging GH rats, the capacity to release ANP on atrial stretch is largely lost, in association with complete suppression of stimulus-induced increase in IP3 levels. These data support a role for IP3 in stretch-mediated atrial ANP secretion and suggest a progressive uncoupling of this signaling pathway in aging hypertensive rats. PMID:7723347

  11. Omega-3 fatty acids and brain resistance to ageing and stress: body of evidence and possible mechanisms.

    PubMed

    Denis, I; Potier, B; Vancassel, S; Heberden, C; Lavialle, M

    2013-03-01

    The increasing life expectancy in the populations of rich countries raises the pressing question of how the elderly can maintain their cognitive function. Cognitive decline is characterised by the loss of short-term memory due to a progressive impairment of the underlying brain cell processes. Age-related brain damage has many causes, some of which may be influenced by diet. An optimal diet may therefore be a practical way of delaying the onset of age-related cognitive decline. Nutritional investigations indicate that the ω-3 poyunsaturated fatty acid (PUFA) content of western diets is too low to provide the brain with an optimal supply of docosahexaenoic acid (DHA), the main ω-3 PUFA in cell membranes. Insufficient brain DHA has been associated with memory impairment, emotional disturbances and altered brain processes in rodents. Human studies suggest that an adequate dietary intake of ω-3 PUFA can slow the age-related cognitive decline and may also protect against the risk of senile dementia. However, despite the many studies in this domain, the beneficial impact of ω-3 PUFA on brain function has only recently been linked to specific mechanisms. This review examines the hypothesis that an optimal brain DHA status, conferred by an adequate ω-3 PUFA intake, limits age-related brain damage by optimizing endogenous brain repair mechanisms. Our analysis of the abundant literature indicates that an adequate amount of DHA in the brain may limit the impact of stress, an important age-aggravating factor, and influences the neuronal and astroglial functions that govern and protect synaptic transmission. This transmission, particularly glutamatergic neurotransmission in the hippocampus, underlies memory formation. The brain DHA status also influences neurogenesis, nested in the hippocampus, which helps maintain cognitive function throughout life. Although there are still gaps in our knowledge of the way ω-3 PUFA act, the mechanistic studies reviewed here indicate that

  12. New compounds able to control hepatic cholesterol metabolism: Is it possible to avoid statin treatment in aged people?

    PubMed Central

    Trapani, Laura; Segatto, Marco; Pallottini, Valentina

    2013-01-01

    Aging is characterized by the loss of homeostasis that leads to changes in the biochemical composition of tissues, reduced ability to respond adaptively to environmental stimuli, and increased susceptibility and vulnerability to diseases including coronary artery diseases, carotid artery disease and brain vessel disease. Hypercholesterolemia is one of the primary risk factors for these pathologies, whose incidence is highly related to aging. Almost 25% of men and 42% of women older than 65 years have a serum total cholesterol level greater than 240 mg/dL. The mechanisms behind this age-related increase in plasma cholesterol are still incompletely understood, thus, the control of plasma cholesterol content in aged people is more challenging than in adults. In this review the different pharmacological approaches to reduce plasma cholesterol levels, particularly in aged people, will be discussed. In brief, current therapies are mostly based on the prescription of statins (3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) that are pretty effective but that exert several side effects. More attention should be given to potential drug interactions, potential age-related changes in drug pharmacokinetics, adverse effects such as myopathy and competing risks when statins are prescribed to old patients. In combination or in alternative to statin therapy, other agents might be required to reduce low density lipoprotein (LDL) cholesterol levels. Among the available drugs, the most commonly prescribed are those addressed to reduce cholesterol absorption, to modulate lipoprotein lipase activity and bile acid sequestrants: even these pharmacological interventions are not exempt from side effects. The use of antioxidants or organoselenium compounds and the discovery of new proteins able to modulate exclusively LDL receptor recycling such as Proprotein convertase subtilisin kexin 9 and SEC24 offer new pharmacological approaches to selectively reduce the main causes of

  13. Aging in cultural context and as narrative process: conceptual foundations of the anthropology of aging as reflected in the works of Margaret Clark and Sharon Kaufman.

    PubMed

    Perkinson, Margaret A; Solimeo, Samantha L

    2014-02-01

    Although the discipline of anthropology has much to contribute to the understanding of the nature and experience of aging, it is a relative latecomer to gerontology. After briefly discussing why this is the case, the authors discuss the contributions of two anthropologists who brought a substantive anthropological voice to gerontological discussion of aging. Examining the "ancestral roots" of the anthropology of aging, we spotlight the intellectual heritage of Margaret Clark, arguably the "mother" of this anthropological subfield, and that of Sharon Kaufman, her student, colleague, and a pioneer in her own right. Clark and Anderson's Culture and aging: an anthropological study of older Americans (1967; Springfield, IL: Charles C. Thomas) remains a touchstone for the concept of situated aging. This examination of value orientations and mental health of older San Franciscans is foundational for understanding aging as an interactive, socially embedded process that is adapted to specific sociocultural contexts. Research and therapies grounded in narrativity and meaning benefit from Sharon Kaufman's The ageless self: sources of meaning in late life (1986; Madison, WI: University of Wisconsin Press), which articulated narrative thinking as a conduit for understanding, performing, and constructing identity and meaning. Kaufman's work has ongoing relevance to gerontological research on embodiment, chronic illness, and later life social transitions. Their research has continued relevance to contemporary gerontological scholarship and practice, signaling both prevailing and emergent agendas for anthropologically informed gerontology.

  14. Integrating Curriculum and Practice with Students and Their Field Supervisors: Reflections on Spirituality and The Aging (Rosa) Model

    ERIC Educational Resources Information Center

    Birkenmaier, Julie; Behrman, Gary; Berg-Weger, Marla

    2005-01-01

    Knowledge and sensitivity about diverse aging populations is a rapidly emerging area of interest in higher education. The next decades will see dramatic increases in the number of older adults in the United States (Administration on Aging (AOA), 2000). Recognizing and utilizing spiritual and religious traditions holds special significance when…

  15. Empowering Youth through a Responsibility-Based Cross-Age Teacher Program: An Investigation into Impact and Possibilities

    ERIC Educational Resources Information Center

    Hammond-Diedrich, Krista C.; Walsh, David

    2006-01-01

    A Responsibility Model-based (RM) (Hellison, 2003) cross-age teaching program was developed to promote the leadership of a selected group of youth from underserved communities. The participants, called the "Urban Youth Leaders," were eight 11 to 15 year old boys who taught various physical activity skills to a group of 40 fourth graders for eight…

  16. Critical Pedagogy in the New Dark Ages: Challenges and Possibilities. Counterpoints: Studies in the Postmodern Theory of Education. Volume 422

    ERIC Educational Resources Information Center

    Nikolakaki, Maria, Ed.

    2012-01-01

    This book unmasks the neoliberal ideology that led modern civilization to withdraw from its previous accomplishments into what may be called the new Dark Ages. The international group of contributors to this volume aggressively rejects the siege of society by capitalism and the resulting deterioration. These authors engage a critical pedagogy that…

  17. miR-23a-3p causes cellular senescence by targeting hyaluronan synthase 2: possible implication for skin aging.

    PubMed

    Röck, Katharina; Tigges, Julia; Sass, Steffen; Schütze, Alexandra; Florea, Ana-Maria; Fender, Anke C; Theis, Florian J; Krutmann, Jean; Boege, Fritz; Fritsche, Ellen; Reifenberger, Guido; Fischer, Jens W

    2015-02-01

    Even though aging and cellular senescence appear to be linked, the biological mechanisms interconnecting these two processes remain to be unravelled. Therefore, microRNA (miRNA/miR) profiles were analyzed ex vivo by means of gene array in fibroblasts isolated from young and old human donors. Expression of several miRNAs was positively correlated with donor age. Among them, miR-23a-3p was shown to target hyaluronan synthase 2 (HAS2). HA is a polysaccharide of the extracellular matrix that critically regulates the phenotype of fibroblasts. Indeed, both aged and senescent fibroblasts showed increased miR-23a-3p expression and secreted significantly lower amounts of HA compared with young and non-senescent fibroblasts. Ectopic overexpression of miR-23a-3p in non-senescent fibroblasts led to decreased HAS2-mediated HA synthesis, upregulation of senescence-associated markers, and decreased proliferation. In addition, siRNA-mediated downregulation of HAS2 and pharmacological inhibition of HA synthesis by 4-methylumbelliferone mimicked the effects of miR-23a-3p. In vivo, miR-23a-3p was upregulated and HAS2 was downregulated in the skin of old mice compared with young mice. Inhibition of HA synthesis by 4-methylumbelliferone in mice reduced dermal hydration and viscoelasticity, thereby mimicking an aged skin phenotype. Taken together, these findings appear to link miR-23a-3p and the HA microenvironment as effector mechanisms in both dermal aging and senescence.

  18. A Reflection on Aging: A Portfolio of Change in Attitudes toward Geriatric Patients during a Clerkship Rotation

    ERIC Educational Resources Information Center

    Del Duca, Danny; Duque, Gustavo

    2006-01-01

    The process of students' evaluation in medical schools has changed from a tutor-led evaluation system based on students' performance to a student-based evaluation that involves self-reflection and their level of change in skills and attitudes. At the McGill University Division of Geriatric Medicine, we developed an innovative system of evaluation…

  19. Frailty's Place in Ethics and Law: Some Thoughts on Equality and Autonomy and on Limits and Possibilities for Aging Citizens.

    PubMed

    McNally, Mary; Lahey, William

    2015-01-01

    Consideration of ethical and legal themes relating to frailty must engage with the concern that frailty is a pejorative concept that validates and reinforces the disadvantage and vulnerability of aging adults. In this chapter, we consider whether a greater focus on frailty may indeed be part of the solution to the disadvantages that aging adults face in achieving equality and maintaining their autonomy within systems that have used their frailty to deny them equality and autonomy. First, by examining equality both as an ethical norm and as a requirement for protections against discrimination, we raise questions about the grounds on which health providers and health systems can be required to give equal concern and respect to the needs of frail older persons. Second, we explore autonomy and identify the tension between meaningful self-determination and prevailing ethical and legal norms associated with informed choice. Third, we argue that a proper understanding of frailty is essential within both of these themes; it respects equality by enabling health providers and systems to identify and address the distinct care needs of aging adults and helps to align informed choice theory with appropriate processes for decision-making about those needs. PMID:26301989

  20. Frailty's Place in Ethics and Law: Some Thoughts on Equality and Autonomy and on Limits and Possibilities for Aging Citizens.

    PubMed

    McNally, Mary; Lahey, William

    2015-01-01

    Consideration of ethical and legal themes relating to frailty must engage with the concern that frailty is a pejorative concept that validates and reinforces the disadvantage and vulnerability of aging adults. In this chapter, we consider whether a greater focus on frailty may indeed be part of the solution to the disadvantages that aging adults face in achieving equality and maintaining their autonomy within systems that have used their frailty to deny them equality and autonomy. First, by examining equality both as an ethical norm and as a requirement for protections against discrimination, we raise questions about the grounds on which health providers and health systems can be required to give equal concern and respect to the needs of frail older persons. Second, we explore autonomy and identify the tension between meaningful self-determination and prevailing ethical and legal norms associated with informed choice. Third, we argue that a proper understanding of frailty is essential within both of these themes; it respects equality by enabling health providers and systems to identify and address the distinct care needs of aging adults and helps to align informed choice theory with appropriate processes for decision-making about those needs.

  1. Possible Mechanisms Underlying Aging-Related Changes in Early Diastolic Filling and Long Axis Motion—Left Ventricular Length and Blood Pressure

    PubMed Central

    Peverill, Roger E.; Chou, Bon; Donelan, Lesley; Mottram, Philip M.; Gelman, John S.

    2016-01-01

    Background The transmitral E wave and the peak velocity of early diastolic mitral annular motion (e`) both decrease with age, but the mechanisms underlying these age-related changes are incompletely understood. This study investigated the possible contributions of blood pressure (BP) and left ventricular end-diastolic length (LVEDL) to age-related reductions in E and e`. Methods The study group were 82 healthy adult subjects <55 years of age who were not obese or hypertensive. Transmitral flow and mitral annular motion were recorded using pulsed-wave Doppler. LVEDL was measured from the mitral annular plane to the apical endocardium. Results Age was positively correlated with diastolic BP and septal wall thickness (SWT), inversely correlated with LVEDL (β = -0.25) after adjustment for sex and body surface area, but was not related to left ventricular end-diastolic diameter (LVEDD). Age was also inversely correlated with E (r = -0.36), septal e`(r = -0.53) and lateral e`(r = -0.53). On multivariable analysis, E was inversely correlated with diastolic BP and LVEDD, septal e`was inversely correlated with diastolic BP and positively correlated with SWT and LVEDL, after adjusting for body mass index, whilst lateral e`was inversely correlated with diastolic BP and positively correlated with LVEDL. Conclusion The above findings are consistent with higher BP being a contributor to age-related reductions in both E and e`and shortening of LVEDL with age being a contributor to the age-related reduction in e`. An implication of these findings is that slowing of myocyte relaxation is unlikely to be the sole, and may not be the main, mechanism underlying age-related decreases in E and e`. PMID:27351745

  2. Possible secondary apatite fission track age standard from altered volcanic ash beds in the middle Jurassic Carmel Formation, Southwestern Utah

    USGS Publications Warehouse

    Kowallis, B.J.; Christiansen, E.H.; Everett, B.H.; Crowley, K.D.; Naeser, C.W.; Miller, D.S.; Deino, A.L.

    1993-01-01

    Secondary age standards are valuable in intra- and interlaboratory calibration. At present very few such standards are available for fission track dating that is older than Tertiary. Several altered volcanic ash beds occur in the Middle Jurassic Carmel Formation in southwestern Utah. The formation was deposited in a shallow marine/sabhka environment. Near Gunlock, Utah, eight ash beds have been identified. Sanidines from one of the ash beds (GUN-F) give a single-crystal laser-probe 40Ar/39Ar age of 166.3??0.8 Ma (2??). Apatite and zircon fission track ages range from 152-185 Ma with typically 15-20 Ma errors (2??). Track densities in zircons are high and most grains are not countable. Apatites are fairly common in most of the ash beds and have reasonable track densities ranging between 1.2-1.5 ?? 106 tracks/cm2. Track length distributions in apatites are unimodal, have standard deviations <1??m, and mean track lengths of about 14-14.5 ??m. High Cl apatites (F:Cl:OH ratio of 39:33:28) are particularly abundant and large in ash GUN-F, and are fairly easy to concentrate, but the concentrates contain some siderite, most of which can be removed by sieving. GUN-F shows evidence of some reworking and detriaal contamination based on older single grain 40Ar/39Ar analyses and some rounding of grains, but the apatite population appears to be largely uncontaminated. At present BJK has approximately 12 of apatite separate from GUN-F. ?? 1993.

  3. Age and provenance of the target materials for tektites and possible impactites as inferred from Sm-Nd and Rb-Sr systematics

    NASA Technical Reports Server (NTRS)

    Shaw, H. F.; Wasserburg, G. J.

    1982-01-01

    Chemical, trace element, and isotopic compositions of tektites are consistent with production by melting of sediments derived from the old terrestrial continental crust. Each tektite group is characterized by a uniform Nd model age, interpreted as the time of formation of the crustal segment which weathered to form the parent sediment for the tektites. Sr model ages are variable within each group, reflecting Rb-Sr fractionation, and, in the favorable limit of very high Rb/Sr ratios, approach the time of sedimentation of the parent material which melted to form the tektites. Unlike tektites, which are dense homogeneous objects, sanidine spherules are porous, fine grained inhomogeneous objects. The leaching experiment employed by the present study shows that the sanidine spherules could have been formed by an oceanic impact involving basaltic crust and overlying sediments or seawater.

  4. Age and dynamics of the Namib Sand Sea: A review of chronological evidence and possible landscape development models

    NASA Astrophysics Data System (ADS)

    Stone, A. E. C.

    2013-06-01

    The Namib Sand Sea constitutes a major physiographic feature of the Namib Desert on the west of Namibia, covering a 50-160 km wide region of the coast between Lüderitz and Walvis Bay. It is widely considered to be one of the oldest desert regions, with a Tertiary-aged fossil desert underlying the modern sand sea. The sand sea has been well studied, benefiting from the presence of the Gobabeb Training and Research Centre during the past 50 years. Whilst much is understood about its sediments and geomorphology, it is only recently that new chronological information, using cosmogenic-nuclide burial dating and optically stimulated luminescence dating have offered new insights, and this calls for an updated review of the age and landscape development of the sand sea. This assessment of the geomorphological and Quaternary dynamics of the region is complemented by developments in the description and analysis of sediment composition. New age control from cosmogenic dating indicates that the sand sea is in excess of a million years old. Initial data from luminescence dating yields depositional ages for dune sediments from three broad areas of the sand sea that include MIS 5, later in the Pleistocene around the Last Glacial Maximum and the Holocene, although it is not expected that these will be the only, or discrete age groupings. Detailed dating and application of ground penetrating radar in the far northern reaches reveals extensive dune migration and deposition during the Holocene. It is important to stress that the upper limit of luminescence dating here is about ˜200 ka (depending on the environmental dose rate of the site) and that migration and reworking of dunes resets the luminescence signal (so what is recorded is(are) the last phase(s) of preserved sediment accumulation). Whilst there are three potential sources of material for the Namib Sand Sea (reworked Tsondab Sandstone (TSS), material from the Great Escarpment derived by rivers and water and wind

  5. Aging and magnetism: Presenting a possible new holistic paradigm for ameliorating the aging process and the effects thereof, through externally applied physiologic PicoTesla magnetic fields.

    PubMed

    Jacobson, Jerry; Sherlag, Benjamin

    2015-09-01

    A new holistic paradigm is proposed for slowing our genomic-based biological clocks (e.g. regulation of telomere length), and decreasing heat energy exigencies for maintenance of physiologic homeostasis. Aging is considered the result of a progressive slow burn in small volumes of tissues with increase in the quantum entropic states; producing desiccation, microscopic scarring, and disruption of cooperative coherent states. Based upon piezoelectricity, i.e. photon-phonon transductions, physiologic PicoTesla range magnetic fields may decrease the production of excessive heat energy through target specific, bio molecular resonant interactions, renormalization of intrinsic electromagnetic tissue profiles, and autonomic modulation. Prospectively, we hypothesize that deleterious effects of physical trauma, immunogenic microbiological agents, stress, and anxiety may be ameliorated. A particle-wave equation is cited to ascertain magnetic field parameters for application to the whole organism thereby achieving desired homeostasis; secondary to restoration of structure and function on quantum levels. We hypothesize that it is at the atomic level that physical events shape the flow of signals and the transmission of energy in bio molecular systems. References are made to experimental data indicating the aspecific efficacy of non-ionizing physiologic magnetic field profiles for treatment of various pathologic states. PMID:26092501

  6. Aging and magnetism: Presenting a possible new holistic paradigm for ameliorating the aging process and the effects thereof, through externally applied physiologic PicoTesla magnetic fields.

    PubMed

    Jacobson, Jerry; Sherlag, Benjamin

    2015-09-01

    A new holistic paradigm is proposed for slowing our genomic-based biological clocks (e.g. regulation of telomere length), and decreasing heat energy exigencies for maintenance of physiologic homeostasis. Aging is considered the result of a progressive slow burn in small volumes of tissues with increase in the quantum entropic states; producing desiccation, microscopic scarring, and disruption of cooperative coherent states. Based upon piezoelectricity, i.e. photon-phonon transductions, physiologic PicoTesla range magnetic fields may decrease the production of excessive heat energy through target specific, bio molecular resonant interactions, renormalization of intrinsic electromagnetic tissue profiles, and autonomic modulation. Prospectively, we hypothesize that deleterious effects of physical trauma, immunogenic microbiological agents, stress, and anxiety may be ameliorated. A particle-wave equation is cited to ascertain magnetic field parameters for application to the whole organism thereby achieving desired homeostasis; secondary to restoration of structure and function on quantum levels. We hypothesize that it is at the atomic level that physical events shape the flow of signals and the transmission of energy in bio molecular systems. References are made to experimental data indicating the aspecific efficacy of non-ionizing physiologic magnetic field profiles for treatment of various pathologic states.

  7. Motivational systems in adolescence: Possible implications for age differences in substance abuse and other risk-taking behaviors

    PubMed Central

    Doremus-Fitzwater, Tamara L.; Varlinskaya, Elena I.; Spear, Linda P.

    2009-01-01

    Adolescence is an evolutionarily conserved developmental phase characterized by hormonal, physiological, neural and behavioral alterations evident widely across mammalian species. For instance, adolescent rats, like their human counterparts, exhibit elevations in peer-directed social interactions, risk-taking/novelty seeking and drug and alcohol use relative to adults, along with notable changes in motivational and reward-related brain regions. After reviewing these topics, the present paper discusses conditioned preference and aversion data showing adolescents to be more sensitive than adults to positive rewarding properties of various drugs and natural stimuli, while less sensitive to the aversive properties of these stimuli. Additional experiments designed to parse specific components of reward-related processing using natural rewards have yielded more mixed findings, with reports of accentuated positive hedonic sensitivity during adolescence contrasting with studies showing less positive hedonic affect and reduced incentive salience at this age. Implications of these findings for adolescent substance abuse will be discussed. PMID:19762139

  8. Do Individual Differences and Aging Effects in the Estimation of Geographical Slant Reflect Cognitive or Perceptual Effects?

    PubMed Central

    Dean, Abigail M.; Oh, Jaehyun; Thomson, Christopher J.; Norris, Catherine J.

    2016-01-01

    Several individual differences including age have been suggested to affect the perception of slant. A cross-sectional study of outdoor hill estimation (N = 106) was analyzed using individual difference measures of age, experiential knowledge, fitness, personality traits, and sex. Of particular note, it was found that for participants who reported any experiential knowledge about slant, estimates decreased (i.e., became more accurate) as conscientiousness increased, suggesting that more conscientious individuals were more deliberate about taking their experiential knowledge (rather than perception) into account. Effects of fitness were limited to those without experiential knowledge, suggesting that they, too, may be cognitive rather than perceptual. The observed effects of age, which tended to produce lower, more accurate estimates of hill slant, provide more evidence that older adults do not see hills as steeper. The main effect of age was to lower slant estimates; such effects may be due to implicit experiential knowledge acquired over a lifetime. The results indicate the impact of cognitive, rather than perceptual factors on individual differences in slant estimation. PMID:27698978

  9. Human Aging and Retirement: Questions Unresolved and Resolved. Some Reflections on Contemporary Gerontology and its Relevance to Retirement Policy.

    ERIC Educational Resources Information Center

    Rhee, H. A.

    The report is a general multidisciplinary survey of current areas of interest in the field of gerontology, especially those having to do with retirement and the provision of social security. Chapter 1 discusses social security as an issue in gerontology and the concern of social security with retirement and aging. Chapter 2 discusses the "Third…

  10. Do Individual Differences and Aging Effects in the Estimation of Geographical Slant Reflect Cognitive or Perceptual Effects?

    PubMed Central

    Dean, Abigail M.; Oh, Jaehyun; Thomson, Christopher J.; Norris, Catherine J.

    2016-01-01

    Several individual differences including age have been suggested to affect the perception of slant. A cross-sectional study of outdoor hill estimation (N = 106) was analyzed using individual difference measures of age, experiential knowledge, fitness, personality traits, and sex. Of particular note, it was found that for participants who reported any experiential knowledge about slant, estimates decreased (i.e., became more accurate) as conscientiousness increased, suggesting that more conscientious individuals were more deliberate about taking their experiential knowledge (rather than perception) into account. Effects of fitness were limited to those without experiential knowledge, suggesting that they, too, may be cognitive rather than perceptual. The observed effects of age, which tended to produce lower, more accurate estimates of hill slant, provide more evidence that older adults do not see hills as steeper. The main effect of age was to lower slant estimates; such effects may be due to implicit experiential knowledge acquired over a lifetime. The results indicate the impact of cognitive, rather than perceptual factors on individual differences in slant estimation.

  11. Decreasing period-length of the endogenous circadian rhythm of oxygen evolution in Acetabularia and its possible relation to aging.

    PubMed

    von Lindern, L; Berger, S

    1996-11-01

    Endogenous circadian rhythms observed under constant conditions normally show period length variations. However, a general trend is difficult to identify when cells or organisms are entrained with the usual 24-h-period light/dark cycles. Therefore, these variations in time have been considered as fluctuations. In order to gain more insight into this phenomenon, individual Acetabularia cells were exposed to light/dark cycles of 16 h (LD 8:8) and 33.6 h (LD 16.8:16.8), respectively, i.e., periods which lie distinctly outside the range of the normal circadian entrainment. Employing a high-resolution procedure for data analysis, decreasing period lengths could consistently be detected when cells were kept under constant conditions for several weeks. Possible causes of this decrease are discussed.

  12. ApoE genotype and familial Alzheimer's disease: a possible influence on age of onset in APP717 Val-->Ile mutated families.

    PubMed

    Nacmias, B; Latorraca, S; Piersanti, P; Forleo, P; Piacentini, S; Bracco, L; Amaducci, L; Sorbi, S

    1995-01-01

    Recent studies have shown a genetic association of the apolipoprotein E (ApoE) epsilon 4 allele with late onset familial and sporadic Alzheimer's disease (AD). In this study we analysed the possible association of the genetic polymorphism of the ApoE gene with age of onset in Italian familial Alzheimer's disease (FAD) families including two early onset familial Alzheimer's (EOFAD) families with the APP717 Val-->Ile mutation in the amyloid precursor protein (APP) gene on chromosome 21. In none of the FAD families analysed was there a significant effect of the ApoE genotype on the age of onset with the exception of one of the two mutated EOFAD families in which the epsilon 2 allele delayed the age of onset. PMID:7746463

  13. Early sponges and toxic protists: possible sources of cryostane, an age diagnostic biomarker antedating Sturtian Snowball Earth.

    PubMed

    Brocks, J J; Jarrett, A J M; Sirantoine, E; Kenig, F; Moczydłowska, M; Porter, S; Hope, J

    2016-03-01

    The period 800-717 million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian successions across the supercontinent Rodinia: the ca. 780 Ma Kanpa Formation of the Western Australian Officer Basin, the ca. 800-740 Ma Visingsö Group of Sweden, and the 740 Ma Chuar Group in Arizona, USA. The distribution of eukaryotic steranes is remarkably similar in the three successions but distinct from all other known younger and older sterane assemblages. Cholestane was the only conventional structure, while indigenous steranes alkylated in position C-24, such as ergostane, stigmastane, dinosterane and isopropylcholestane, and n-propylcholestane, were not observed. This sterane distribution appears to be age diagnostic for the pre-Sturtian Neoproterozoic. It attests to the distinct evolutionary state of pre-Snowball eukaryotes, pointing to a taxonomic disparity that was still lower than in the Ediacaran (635-541 Ma). All three basins also show the presence of a new C28 sterane that was tentatively identified as 26-methylcholestane, here named cryostane. The only known extant organisms that can methylate sterols in the 26-position are demosponges. This assignment is plausible as molecular clocks place the appearance of the earliest animals into the pre-Sturtian Neoproterozoic. The unusual 26-methylsterol may have protected sponges, but also other eukaryotes, against their own membranolytic toxins. Some protists release lytic toxins to deter predators and kill eukaryotic prey. As conventional membrane sterols can be the site of attack for these toxins, sterols with unusual side-chain modification protect the cell. This interpretation of cryostane supports fossil evidence of predation in the Chuar Group and promotes hypotheses about the

  14. Reflecting Reflective Practice

    ERIC Educational Resources Information Center

    Galea, Simone

    2012-01-01

    This paper demystifies reflective practice on teaching by focusing on the idea of reflection itself and how it has been conceived by two philosophers, Plato and Irigaray. It argues that reflective practice has become a standardized method of defining the teacher in teacher education and teacher accreditation systems. It explores how practices of…

  15. Early sponges and toxic protists: possible sources of cryostane, an age diagnostic biomarker antedating Sturtian Snowball Earth.

    PubMed

    Brocks, J J; Jarrett, A J M; Sirantoine, E; Kenig, F; Moczydłowska, M; Porter, S; Hope, J

    2016-03-01

    The period 800-717 million years (Ma) ago, in the lead-up to the Sturtian Snowball glaciation, saw an increase in the diversity of eukaryotic microfossils. To afford an independent and complementary view of this evolutionary period, this study presents the distribution of eukaryotic biomarkers from three pre-Sturtian successions across the supercontinent Rodinia: the ca. 780 Ma Kanpa Formation of the Western Australian Officer Basin, the ca. 800-740 Ma Visingsö Group of Sweden, and the 740 Ma Chuar Group in Arizona, USA. The distribution of eukaryotic steranes is remarkably similar in the three successions but distinct from all other known younger and older sterane assemblages. Cholestane was the only conventional structure, while indigenous steranes alkylated in position C-24, such as ergostane, stigmastane, dinosterane and isopropylcholestane, and n-propylcholestane, were not observed. This sterane distribution appears to be age diagnostic for the pre-Sturtian Neoproterozoic. It attests to the distinct evolutionary state of pre-Snowball eukaryotes, pointing to a taxonomic disparity that was still lower than in the Ediacaran (635-541 Ma). All three basins also show the presence of a new C28 sterane that was tentatively identified as 26-methylcholestane, here named cryostane. The only known extant organisms that can methylate sterols in the 26-position are demosponges. This assignment is plausible as molecular clocks place the appearance of the earliest animals into the pre-Sturtian Neoproterozoic. The unusual 26-methylsterol may have protected sponges, but also other eukaryotes, against their own membranolytic toxins. Some protists release lytic toxins to deter predators and kill eukaryotic prey. As conventional membrane sterols can be the site of attack for these toxins, sterols with unusual side-chain modification protect the cell. This interpretation of cryostane supports fossil evidence of predation in the Chuar Group and promotes hypotheses about the

  16. From 'the thing to do' to 'defying the ravages of age': older women reflect on the use of lipstick.

    PubMed

    Clarke, Laura Hurd; Bundon, Andrea

    2009-01-01

    Using data from in-depth interviews with 36 women, aged 71 to 93, this manuscript examines older women's use of lipstick. The most ubiquitously used cosmetic by the women we interviewed, lipstick was a taken-for-granted practice in the women's performance of gender. In the women's youth, the performance of gender through lipstick usage was related to rebellion and peer acceptance. In contrast, the use of lipstick in later life was related to the maintenance of an attractive and respectable appearance. We discuss our findings in light of interpretative feminist theorizing concerning beauty work, doing gender, and the presentation of self.

  17. From 'the thing to do' to 'defying the ravages of age': older women reflect on the use of lipstick.

    PubMed

    Clarke, Laura Hurd; Bundon, Andrea

    2009-01-01

    Using data from in-depth interviews with 36 women, aged 71 to 93, this manuscript examines older women's use of lipstick. The most ubiquitously used cosmetic by the women we interviewed, lipstick was a taken-for-granted practice in the women's performance of gender. In the women's youth, the performance of gender through lipstick usage was related to rebellion and peer acceptance. In contrast, the use of lipstick in later life was related to the maintenance of an attractive and respectable appearance. We discuss our findings in light of interpretative feminist theorizing concerning beauty work, doing gender, and the presentation of self. PMID:20183145

  18. Modeling the relative roles of the foehn wind and urban expansion in the 2002 Beijing heat wave and possible mitigation by high reflective roofs

    NASA Astrophysics Data System (ADS)

    Ma, Hongyun; Shao, Haiyan; Song, Jie

    2014-02-01

    Rapid urbanization has intensified summer heat waves in recent decades in Beijing, China. In this study, effectiveness of applying high-reflectance roofs on mitigating the warming effects caused by urban expansion and foehn wind was simulated for a record-breaking heat wave occurred in Beijing during July 13-15, 2002. Simulation experiments were performed using the Weather Research and Forecast (WRF version 3.0) model coupled with an urban canopy model. The modeled diurnal air temperatures were compared well with station observations in the city and the wind convergence caused by urban heat island (UHI) effect could be simulated clearly. By increasing urban roof albedo, the simulated UHI effect was reduced due to decreased net radiation, and the simulated wind convergence in the urban area was weakened. Using WRF3.0 model, the warming effects caused by urban expansion and foehn wind were quantified separately, and were compared with the cooling effect due to the increased roof albedo. Results illustrated that the foehn warming effect under the northwesterly wind contributed greatly to this heat wave event in Beijing, while contribution from urban expansion accompanied by anthropogenic heating was secondary, and was mostly evident at night. Increasing roof albedo could reduce air temperature both in the day and at night, and could more than offset the urban expansion effect. The combined warming caused by the urban expansion and the foehn wind could be potentially offset with high-reflectance roofs by 58.8 % or cooled by 1.4 °C in the early afternoon on July 14, 2002, the hottest day during the heat wave.

  19. Late quaternary distribution of the Cycladophora davisiana radiolarian species: Reflection of possible ventilation of the North Pacific intermediate water during the Last Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Matul, A. G.; Abelmann, A.; Gersonde, R.; Nürnberg, D.; Tiedemann, R.; Kruglikova, S. B.

    2015-02-01

    A comparison of micropaleontological data on the distribution of the Cycladophora davisiana radiolarian species in the surface sediment layer and the Late Quaternary sediments from the Subarctic Pacific and Far East marginal seas allowed conclusions concerning the possible conditions and occurrence of intermediate waters during the last glacial maximum. We used the modern data on the C. davisiana species, which is a micro-paleontological indicator of the cold oxygen-rich upper intermediate water mass, which is now forming only in the Sea of Okhotsk. The high amount of C. davisiana in sediments of the last glacial maximum may point to the possible formation and expansion of the ventilated intermediate water in the most part of the Subarctic paleo-Pacific: the Bering Sea, the Sea of Okhotsk, within the NW Gyre, and in the Gulf of Alaska.

  20. Update: Interim Guidance for Health Care Providers Caring for Women of Reproductive Age with Possible Zika Virus Exposure--United States, 2016.

    PubMed

    Petersen, Emily E; Polen, Kara N D; Meaney-Delman, Dana; Ellington, Sascha R; Oduyebo, Titilope; Cohn, Amanda; Oster, Alexandra M; Russell, Kate; Kawwass, Jennifer F; Karwowski, Mateusz P; Powers, Ann M; Bertolli, Jeanne; Brooks, John T; Kissin, Dmitry; Villanueva, Julie; Muñoz-Jordan, Jorge; Kuehnert, Matthew; Olson, Christine K; Honein, Margaret A; Rivera, Maria; Jamieson, Denise J; Rasmussen, Sonja A

    2016-04-01

    CDC has updated its interim guidance for U.S. health care providers caring for women of reproductive age with possible Zika virus exposure to include recommendations on counseling women and men with possible Zika virus exposure who are interested in conceiving. This guidance is based on limited available data on persistence of Zika virus RNA in blood and semen. Women who have Zika virus disease should wait at least 8 weeks after symptom onset to attempt conception, and men with Zika virus disease should wait at least 6 months after symptom onset to attempt conception. Women and men with possible exposure to Zika virus but without clinical illness consistent with Zika virus disease should wait at least 8 weeks after exposure to attempt conception. Possible exposure to Zika virus is defined as travel to or residence in an area of active Zika virus transmission ( http://www.cdc.gov/zika/geo/active-countries.html), or sex (vaginal intercourse, anal intercourse, or fellatio) without a condom with a man who traveled to or resided in an area of active transmission. Women and men who reside in areas of active Zika virus transmission should talk with their health care provider about attempting conception. This guidance also provides updated recommendations on testing of pregnant women with possible Zika virus exposure. These recommendations will be updated when additional data become available.

  1. Update: Interim Guidance for Health Care Providers Caring for Women of Reproductive Age with Possible Zika Virus Exposure--United States, 2016.

    PubMed

    Petersen, Emily E; Polen, Kara N D; Meaney-Delman, Dana; Ellington, Sascha R; Oduyebo, Titilope; Cohn, Amanda; Oster, Alexandra M; Russell, Kate; Kawwass, Jennifer F; Karwowski, Mateusz P; Powers, Ann M; Bertolli, Jeanne; Brooks, John T; Kissin, Dmitry; Villanueva, Julie; Muñoz-Jordan, Jorge; Kuehnert, Matthew; Olson, Christine K; Honein, Margaret A; Rivera, Maria; Jamieson, Denise J; Rasmussen, Sonja A

    2016-01-01

    CDC has updated its interim guidance for U.S. health care providers caring for women of reproductive age with possible Zika virus exposure to include recommendations on counseling women and men with possible Zika virus exposure who are interested in conceiving. This guidance is based on limited available data on persistence of Zika virus RNA in blood and semen. Women who have Zika virus disease should wait at least 8 weeks after symptom onset to attempt conception, and men with Zika virus disease should wait at least 6 months after symptom onset to attempt conception. Women and men with possible exposure to Zika virus but without clinical illness consistent with Zika virus disease should wait at least 8 weeks after exposure to attempt conception. Possible exposure to Zika virus is defined as travel to or residence in an area of active Zika virus transmission ( http://www.cdc.gov/zika/geo/active-countries.html), or sex (vaginal intercourse, anal intercourse, or fellatio) without a condom with a man who traveled to or resided in an area of active transmission. Women and men who reside in areas of active Zika virus transmission should talk with their health care provider about attempting conception. This guidance also provides updated recommendations on testing of pregnant women with possible Zika virus exposure. These recommendations will be updated when additional data become available. PMID:27031943

  2. Symptom Clusters in Patients Presenting to the Emergency Department with Possible Acute Coronary Syndrome Differ by Sex, Age, and Discharge Diagnosis

    PubMed Central

    Rosenfeld, Anne G.; Knight, Elizabeth P.; Steffen, Alana; Burke, Larisa; Daya, Mohamud; DeVon, Holli A.

    2015-01-01

    Objectives To identify classes of individuals presenting to the ED for suspected ACS who shared similar symptoms and clinical characteristics. Background Describing symptom clusters in undiagnosed patients with suspected ACS is a novel and clinically relevant approach, reflecting real-world emergency department evaluation procedures Methods Symptoms were measured using a validated 13-item symptom checklist. Latent class analysis was used to describe symptom clusters. Results The sample of 874 was 37% female with a mean age of 59.9 years. Four symptom classes were identified: Heavy Symptom Burden (Class 1), Chest Symptoms and Shortness of Breath (Class 2), Chest Symptoms Only (Class 3), and Weary (Class 4). Patients with ACS were more likely to cluster in Classes 2 and 3. Women and younger patients were more likely to group in Class 1. Conclusions Further research is needed to determine the value of symptom clusters in the ED triage and management of suspected ACS. PMID:26118542

  3. Evaluating Computer Screen Time and Its Possible Link to Psychopathology in the Context of Age: A Cross-Sectional Study of Parents and Children

    PubMed Central

    Ross, Sharon; Silman, Zmira; Maoz, Hagai; Bloch, Yuval

    2015-01-01

    Background Several studies have suggested that high levels of computer use are linked to psychopathology. However, there is ambiguity about what should be considered normal or over-use of computers. Furthermore, the nature of the link between computer usage and psychopathology is controversial. The current study utilized the context of age to address these questions. Our hypothesis was that the context of age will be paramount for differentiating normal from excessive use, and that this context will allow a better understanding of the link to psychopathology. Methods In a cross-sectional study, 185 parents and children aged 3–18 years were recruited in clinical and community settings. They were asked to fill out questionnaires regarding demographics, functional and academic variables, computer use as well as psychiatric screening questionnaires. Using a regression model, we identified 3 groups of normal-use, over-use and under-use and examined known factors as putative differentiators between the over-users and the other groups. Results After modeling computer screen time according to age, factors linked to over-use were: decreased socialization (OR 3.24, Confidence interval [CI] 1.23–8.55, p = 0.018), difficulty to disengage from the computer (OR 1.56, CI 1.07–2.28, p = 0.022) and age, though borderline-significant (OR 1.1 each year, CI 0.99–1.22, p = 0.058). While psychopathology was not linked to over-use, post-hoc analysis revealed that the link between increased computer screen time and psychopathology was age-dependent and solidified as age progressed (p = 0.007). Unlike computer usage, the use of small-screens and smartphones was not associated with psychopathology. Conclusions The results suggest that computer screen time follows an age-based course. We conclude that differentiating normal from over-use as well as defining over-use as a possible marker for psychiatric difficulties must be performed within the context of age. If verified by

  4. Impact of age on aortic wave reflection responses to metaboreflex activation and its relationship with leg lean mass in post-menopausal women.

    PubMed

    Figueroa, Arturo; Jaime, Salvador J; Johnson, Sarah A; Alvarez-Alvarado, Stacey; Campbell, Jeremiah C; Feresin, Rafaela G; Elam, Marcus L; Arjmandi, Bahram H

    2015-10-01

    Wave reflection (augmentation pressure [AP] and index [AIx]) is greater in older women than men. Resting AP is a better wave reflection index than AIx in older adults. The negative relationship between wave reflection and lean mass (LM) has been inconsistent. We investigated the impact of age and LM on aortic hemodynamic responses to metaboreflex activation in post-menopausal women. Post-menopausal women, younger and older (n=20 per group) than 60 years, performed 2-min isometric handgrip at 30% of maximal force followed by 3-min post-exercise muscle ischemia (PEMI). We measured carotid-femoral pulse wave velocity (cfPWV) and femoral-ankle PWV (faPWV) at rest, and aortic systolic blood pressure (aSBP), pulse pressure (aPP), AP, AIx, and AIx-adjusted for heart rate (AIx@75) at rest and during PEMI using tonometry. Arm and leg LM were measured by DEXA. Resting cfPWV, aSBP, and aPP were higher, while AIx@75 and leg LM were lower in older than younger women. aSBP and aPP increased similarly during PEMI in both groups. Increases in AP (P<0.05), AIx (P<0.05), and AIx@75 (P<0.01) during PEMI were greater in older than younger women. From these responses, only AP during PEMI was correlated (P<0.05) positively with aSBP and aPP responses, and negatively with leg LM. Resting faPWV, but not cfPWV, was correlated (P<0.01) with AP, aSBP, and aPP during PEMI. Therefore, PEMI induces greater wave reflection responses in older than younger post-menopausal women. Our findings suggest that the increased AP response to PEMI is related to leg arterial stiffness and muscle loss in older women.

  5. [ACOUSTIC FEATURES OF VOCALIZATIONS, REFLECTING THE DISCOMFORT AND COMFORT STATE OF INFANTS AGED THREE AND SIX MONTHS].

    PubMed

    Pavlikova, M I; Makarov, A K; Lyakso, E E

    2015-08-01

    The paper presented the possibility of recognition by adult the comfort and discomfort state of 3 and 6 months old infant's on the base of their vocalizations. The acoustic features of the vocalizations that are important for the recognition of the infant state of the characteristics of voice was described. It is shown that discomfort vocalizations differ from comfort ones on the basis of the average and maximum values of pitch, pitch values in the central and final part of the vocalization. A mathematical model is proposed and described a classification function signal of discomfort and comfort. Was found that the vocalizations of infants attributable adults with a probability of 0.75 and above the categories of comfort and discomfort with high reliability are recognized by the mathematical model based on a classification function.

  6. Does the myth of Phaethon reflect an impact? Revising the fall of Phaethon and considering a possible relation to the Chiemgau Impact

    NASA Astrophysics Data System (ADS)

    Rappenglock, B.; Rappenglock, M.

    In Greek Mythology there exists one story that has repeatedly been interpreted to describe the fall of a celestial body: the story of Phaethon, who undertakes a disastrous drive with the sun-chariot of his father Helios. First, the article presents the arguments given by ancient authors for interpreting this story as the reflection of a natural phenomenon. Then details given in the old descriptions of Phaethon's fall are compared with nowadays knowledge of impact phenomena. Furthermore the texts are examined for clues to the time and the location of the hypothesized impact. These considerations called Chiemgau Impact. The impact struck the south-east of Bavaria Germany at some time during the Celtic period and left an extended crater-strewnfield of about 100 craters. A conspicuous intersection between the tradition of the Phaethon story and the up to now known time-frame for the Chiemgau Impact gives new clues for dating the Chiemgau Impact to the time between 600 and 428 B.C.

  7. Possible relationship of cranial traumatic injuries with violence in the south-east Iberian Peninsula from the Neolithic to the Bronze Age.

    PubMed

    Jiménez-Brobeil, S A; du Souich, Ph; Al Oumaoui, I

    2009-11-01

    The main aim of this study was to analyze the presence and distribution of cranial trauma, as possible evidence of violence, in remains from the Neolithic to Bronze Age from the SE Iberian Peninsula. The sample contains skulls, crania, and cranial vaults belonging to 410 prehistoric individuals. We also studied 267 crania from medieval and modern times for comparative purposes. All lesions in the prehistoric crania are healed and none of them can be attributed to a specific weapon. In all studied populations, injuries were more frequent in adults than in subadults and also in males than in females, denoting a sexual division in the risk of suffering accidents or intentional violence. According to the archeological record, the development of societies in the SE Iberian Peninsula during these periods must have entailed an increase in conflict. However, a high frequency of cranial traumatic injuries was observed in the Neolithic series, theoretically a less conflictive time, and the lowest frequency was in crania from the 3rd millennium B.C. (Copper Age), which is characterized by the archeologists as a period of increasing violence. The relatively large size and the high rate of injuries in Neolithic crania and the practice of cannibalism are strongly suggestive of episodes of interpersonal or intergroup conflict. The number and distribution of injuries in Bronze Age is consistent with the increase in violence at that time described by most archeologists. PMID:19425096

  8. Possible relationship of cranial traumatic injuries with violence in the south-east Iberian Peninsula from the Neolithic to the Bronze Age.

    PubMed

    Jiménez-Brobeil, S A; du Souich, Ph; Al Oumaoui, I

    2009-11-01

    The main aim of this study was to analyze the presence and distribution of cranial trauma, as possible evidence of violence, in remains from the Neolithic to Bronze Age from the SE Iberian Peninsula. The sample contains skulls, crania, and cranial vaults belonging to 410 prehistoric individuals. We also studied 267 crania from medieval and modern times for comparative purposes. All lesions in the prehistoric crania are healed and none of them can be attributed to a specific weapon. In all studied populations, injuries were more frequent in adults than in subadults and also in males than in females, denoting a sexual division in the risk of suffering accidents or intentional violence. According to the archeological record, the development of societies in the SE Iberian Peninsula during these periods must have entailed an increase in conflict. However, a high frequency of cranial traumatic injuries was observed in the Neolithic series, theoretically a less conflictive time, and the lowest frequency was in crania from the 3rd millennium B.C. (Copper Age), which is characterized by the archeologists as a period of increasing violence. The relatively large size and the high rate of injuries in Neolithic crania and the practice of cannibalism are strongly suggestive of episodes of interpersonal or intergroup conflict. The number and distribution of injuries in Bronze Age is consistent with the increase in violence at that time described by most archeologists.

  9. The expression of NLRX1 in C57BL/6 mice cochlear hair cells: Possible relation to aging- and neomycin-induced deafness.

    PubMed

    Yang, Qianqian; Sun, Gaoying; Cao, Zhixin; Yin, Haiyan; Qi, Qi; Wang, Jinghan; Liu, Wenwen; Bai, Xiaohui; Wang, Haibo; Li, Jianfeng

    2016-03-11

    Nucleotide-binding domain and leucine-rich-repeat-containing family member X1 (NLRX1) is a cytoplasmic pattern recognition receptor that is predominantly located in mitochondria, which is tightly related to mitochondrial damage, reactive oxygen species (ROS) production, inflammation and apoptosis. The present study was designed to explore whether NLRX1 expresses in C57BL/6 mice cochlear hair cells and, if so, to investigate the possible correlations between NLRX1 and hearing. The location and dynamic expression of NLRX1 were investigated by immunofluorescence, real-time PCR and Western blotting. Hearing thresholds of C57BL/6 mice were measured by auditory brainstem response (ABR). Moreover, the downstream inflammatory and apoptotic pathways regulated by NLRX1 were examined in age-related and neomycin-induced hair cell damage. Data showed that NLRX1 expressed in cytoplasm of C57BL/6 cochlear hair cells, especially in the cilia, which were essential for sound sensation. The expression of NLRX1 in hair cells increased as the mice grew up, and, decreased as they aged. Additionally, the activated apoptotic JNK pathway was detected in 9-month old mice with worse-hearing and 3-month old mice treated with neomycin. Overall, results indicate that NLRX1 may relate to hair cell maturity, hearing formation and maintenance, and promote hair cell apoptosis through JNK pathway induced by aging and neomycin.

  10. The expression of NLRX1 in C57BL/6 mice cochlear hair cells: Possible relation to aging- and neomycin-induced deafness.

    PubMed

    Yang, Qianqian; Sun, Gaoying; Cao, Zhixin; Yin, Haiyan; Qi, Qi; Wang, Jinghan; Liu, Wenwen; Bai, Xiaohui; Wang, Haibo; Li, Jianfeng

    2016-03-11

    Nucleotide-binding domain and leucine-rich-repeat-containing family member X1 (NLRX1) is a cytoplasmic pattern recognition receptor that is predominantly located in mitochondria, which is tightly related to mitochondrial damage, reactive oxygen species (ROS) production, inflammation and apoptosis. The present study was designed to explore whether NLRX1 expresses in C57BL/6 mice cochlear hair cells and, if so, to investigate the possible correlations between NLRX1 and hearing. The location and dynamic expression of NLRX1 were investigated by immunofluorescence, real-time PCR and Western blotting. Hearing thresholds of C57BL/6 mice were measured by auditory brainstem response (ABR). Moreover, the downstream inflammatory and apoptotic pathways regulated by NLRX1 were examined in age-related and neomycin-induced hair cell damage. Data showed that NLRX1 expressed in cytoplasm of C57BL/6 cochlear hair cells, especially in the cilia, which were essential for sound sensation. The expression of NLRX1 in hair cells increased as the mice grew up, and, decreased as they aged. Additionally, the activated apoptotic JNK pathway was detected in 9-month old mice with worse-hearing and 3-month old mice treated with neomycin. Overall, results indicate that NLRX1 may relate to hair cell maturity, hearing formation and maintenance, and promote hair cell apoptosis through JNK pathway induced by aging and neomycin. PMID:26836140

  11. Dying in a rural residential aged care facility: an action research and reflection project to improve end-of-life care to residents with a non-malignant disease.

    PubMed

    Rowley, Joanne; Taylor, Beverley

    2011-12-01

    This article describes a qualitative research project that explored issues around end-of-life care provided to residents dying from non-malignant diseases in two, rural Australian, residential aged care facilities. Reflective processes and action research were combined to work in collaboration with 14 aged nurses, associated staff and relatives of dying residents. Reflection featured in the research and included group reflection on practice stories, critical reflection during thematic analysis and reflection on action research cycles. Themes and subthemes emerged, indicating that aspects of end-of-life care needed further improvement. Major thematic concerns were prioritized for action and included the need for better pain management practices which will be discussed. Identifying these clinical issues was an important step in creating, implementing and evaluating actions. Participants reported varying degrees of success in attempting to improve end-of-life care.

  12. Late Pleistocene sediments and fossils near the mouth of Mad River, Humboldt County, California: Facies analysis, sequence development, and possible age correlation

    SciTech Connect

    Harvey, E.W. . Dept. of Geological Sciences)

    1994-04-01

    Study of late Pleistocene-age sediments near the mouth of the Mad River revealed a sequence of nearshore marine and shallow bay deposits. This sequence, bounded by unconformities, is informally named the Mouth of Mad unit. The Mouth of mad unit can be divided into four distinct depositional facies at the study site. The lowest facies are the Nearshore Sand and Estuarine Mud, which lie unconformably on a paleosol. The sand facies grades upward into a high-energy, interbedded Nearshore Sand and Gravel facies containing storm and rip-channel deposits. Above the sand and gravel is a Strand-Plain Sand facies. This sand is overlain by a laterally variable sequence of shell-rich Bay facies. The bay deposits can be further divided into five subfacies: (1) a Bioturbated Sand; (2) a Lower Tidal Flat Mud; (3) a Mixed Sand and Mud; (4) an oyster-rich Bay Mud; and (5) an Upper Tidal Flat Mud. The bay sequence is overlain unconformably by younger late Pleistocene-age marine terrace deposits. The depositional environments represented by these facies progress from a shoreline estuary to nearshore deposits, above storm wave base, and slowly back to shoreline and finally shallow bay conditions. The Mouth of Mad unit represents a transgressive-regressive sequence, involving the development of a protective spit. The uppermost mud within the Mouth of Mad unit has been dated, using thermoluminescence age estimation, at 176 [+-] 33 ka, placing it in the late Pleistocene. The Mouth of Mad unit appears to be younger than the fossiliferous deposits at Elk Head, Crannell Junction, Trinidad Head, Moonstone Beach, and the Falor Formation near Maple Creek, and possibly time equivalent with gravel deposits exposed at the western end of School Road in McKinleyville.

  13. Elemental analysis of human amniotic fluid and placenta by total-reflection X-ray fluorescence and energy-dispersive X-ray fluorescence: child weight and maternal age dependence

    NASA Astrophysics Data System (ADS)

    Carvalho, M. L.; Custódio, P. J.; Reus, U.; Prange, A.

    2001-11-01

    This work is an attempt to evaluate the possible influence of the mother's age in trace element concentrations in human amniotic fluid and placenta and whether these concentrations are correlated to the weight of the newborn infants. Total-reflection X-ray fluorescence (TXRF) was used to analyze 16 amniotic fluid samples, and the placenta samples were analyzed by energy dispersive X-ray fluorescence (EDXRF). The whole samples were collected during delivery from healthy mothers and healthy infants and full-term pregnancies. According to the age of the mother, three different groups were considered: 20-25, 25-30 and 30-40 years old. Only two mothers were aged more than 35 years. The weight of the infants ranged from 2.56 to 4.05 kg and three groups were also considered: 2.5-3, 3-3.5 and 3.5-4 kg. The organic matrix of the amniotic fluid samples was removed by treatment with HNO 3 followed by oxygen plasma ashing. Yttrium was used as the internal standard for TXRF analysis. Placenta samples were lyophilized and analyzed by EDXRF without any chemical treatment. Very low levels of Ni and Sr were found in the amniotic fluid samples, and were independent of the age of the mother and weight of the child. Cr, Mn, Se and Pb were at the level of the detection limit. Zn, considered one of the key elements in neonatal health, was not significantly different in the samples analyzed; however, it was weakly related to birth weigh. The concentrations obtained ranged from 0.11 to 0.92 mg/l and 30 to 65 μg/g in amniotic fluid and placenta, respectively. The only two elements which seemed to be significantly correlated with mother's age and newborn weight were Ca and Fe for both types of sample: Ca levels were increased in heavier children and older mothers; however, Fe increased with increasing maternal age, but decreased for heavier babies. The same conclusions were obtained for placenta and amniotic fluid samples. Cu is closely associated with Fe in its function in the organism

  14. The relationship between parental education and adolescents' soft drink intake from the age of 11-13 years, and possible mediating effects of availability and accessibility.

    PubMed

    Totland, Torunn H; Lien, Nanna; Bergh, Ingunn H; Bjelland, Mona; Gebremariam, Mekdes K; Klepp, Knut-Inge; Andersen, Lene F

    2013-09-14

    The present study examined the prospective relationship between parental education and adolescents' soft drink intake over 20 months, and possible mediating effects of adolescents' availability and accessibility of soft drinks at home. A total of 866 adolescents, with data on two time points in the Norwegian HEalth In Adolescents (HEIA) cohort study (2007-9), were included in the analyses. Data on intake and determinants of soft drinks were collected from adolescents and both parents by questionnaires. Mediation analyses using linear regression investigated the total and direct effects of parental education on adolescents' soft drink intake from the age of 11-13 years. In order to investigate prospective relationships, two models were set up to measure the (1) prediction and (2) change in consumption over 20 months. Possible mediation effects of availability and perceived accessibility at home were further examined in both models. The results showed that a lower level of parental education predicted a higher intake of soft drinks among adolescents after 20 months, and that higher perceived accessibility of soft drinks reported by adolescents and mothers explained 39 % of the total effect. No relationship was observed between parental education and the change in adolescents' intake of soft drinks over 20 months. Interventions aimed at families with low parental education should target the perceived accessibility of soft drinks at home in order to diminish social differences in adolescents' soft drink consumption.

  15. Reflective Teaching

    ERIC Educational Resources Information Center

    Farrell, Thomas S. C.

    2013-01-01

    Thomas Farrell's "Reflective Teaching" outlines four principles that take teachers from just doing reflection to making it a way of being. Using the four principles, Reflective Practice Is Evidence Based, Reflective Practice Involves Dialogue, Reflective Practice Links Beliefs and Practices, and Reflective Practice Is a Way of Life,…

  16. Evidence that glucose metabolism is decreased in the cerebrum of aged female senescence-accelerated mouse; possible involvement of a low hexokinase activity.

    PubMed

    Kurokawa, T; Sato, E; Inoue, A; Ishibashi, S

    1996-08-16

    d-Glucose metabolism in cerebral cells prepared from aged senescence-accelerated mouse (SAM), was investigated in consideration of a sex difference. The production of 14CO2 from 6-[14C]D-glucose was reduced in female senescence-accelerated-prone mouse (SAMP) 8, a prone substrain, in comparison with that in female senescence-accelerated-resistant mouse (SAMR) 2, a control substrain, whereas there was no difference in males. The 2-deoxy-D-glucose uptake into cerebral cells from female SAMP8 was also lower than that of control mice. But, the 3-O-methyl-D-glucose uptake in SAMP8 was higher than that of SAMR2, suggesting that the low hexokinase activity was involved in the decreased glucose metabolism in cerebrum of SAMP8 females irrespective of glucose transporter. This possibility was supported by the finding that the contents of glucose 6-phosphate produced from glucose added to cerebral cells from SAMP8 was lower than that in ICR mice. PMID:8873128

  17. Reflection Coefficients.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1994-01-01

    Discusses and provides an example of reflectivity approximation to determine whether reflection will occur. Provides a method to show thin-film interference on a projection screen. Also applies the reflectivity concepts to electromagnetic wave systems. (MVL)

  18. New Constraints on the Age of the Opening of the South Atlantic Basin As Revealed By Recently Acquired Magnetic, Gravity and Seismic Reflection Data

    NASA Astrophysics Data System (ADS)

    Hall, S. A.; Bird, D. E.; Danque, H. A.; Grant, J. V.; McLean, D. J.; Towle, P. J.

    2014-12-01

    Detailed, high quality, marine total field magnetic data has been recently acquired over parts of the South Atlantic ocean off the southwestern margin of South Africa. These data display a pattern of well-defined, NW-SE striking linear magnetic anomalies along the margin that can be traced with confidence over distances > 150 km. The anomalies are interpreted to be M-series seafloor spreading anomalies M9 to M11, which are consistent with the initiation of seafloor spreading around 135 Ma (Late Valanginian). Corresponding M-series anomalies M9 and M10 have previously been reported for the conjugate South American margin offshore Argentina, however the presence of the M11 series SE of the Cape Lineament suggests an earlier opening of the southern South Atlantic basin than previously recognized. Breaks in the continuity of the linear anomaly pattern, observed in map view, have generally NE-SW trends and are considered sites of possible fracture zones. One such discontinuity, which we have termed the "Cape Lineament" (CL), marks a significant change in crustal character and Cretaceous depositional history, as revealed by gravity data and seismic reflection data respectively. Crust NW of CL appears to be characterized by greater thicknesses and the presence of seaward dipping reflectors (SDRs), whereas crust SE of CL has more "normal" oceanic thicknesses and SDRs that are either absent or more limited in areal extent. Although linear magnetic anomalies are observed both NW and SE of CL, anomalies to the SE display a better correlation with those predicted by our seafloor spreading model.

  19. The release of sympathetic neurotransmitters is impaired in aged rats after an inflammatory stimulus. A possible link between cytokine production and sympathetic transmission

    PubMed Central

    Donoso, Verónica; Gomez, Christian R.; Orriantia, Miguel Ángel; Pérez, Viviana; Torres, Claudio; Coddou, Claudio; Nelson, Pablo; Maisey, Kevin; Morales, Bernardo; Fernandez, Ricardo; Imarai, Mónica; Huidobro-Toro, Juan Pablo; Sierra, Felipe; Acuña-Castillo, Claudio

    2009-01-01

    Aging results in a general decline in the response to external insults, including acute inflammatory challenges. In young animals, the inflammatory response requires activation of the sympathetic system, including neurotransmitters such as ATP, and catecholamines (epinephrine and norepinephrine). To test whether aging affects activation of this axis, and whether this in turn might affect cytokine release, we administered lipopolysaccharide (LPS) i.p. to adult, middle-aged and aged Fisher 344 rats (6, 15 and 23-month old, respectively) and evaluated the early (0–12 hours) serum levels of Neuropeptide-Y (NP-Y), ATP and vanillyl mandelic acid (VMA, as an indirect measurement of catecholamine levels). In addition, we evaluated the association between these factors and serum levels of the cytokines tumor necrosis factor-alpha (TNFα)3 and interleukin-10 (IL-10). Induction of both ATP and NP-Y was markedly reduced in the serum of aged animals, when compared to their younger counterparts, while induction of VMA was not affected by age. In spite of these changes, serum levels of TNFα and IL-10 were strongly hyper induced and delayed in aged rats. The results suggest that during aging there is a dysregulation in sympathetic neurotransmitter regulatory mechanisms, and this might play a role in the impairment of the inflammatory response. PMID:18973771

  20. Posttranscriptional Suppression of Lipopolysaccharide-Stimulated Inflammatory Responses by Macrophages in Middle-Aged Mice: A Possible Role for Eukaryotic Initiation Factor 2 α.

    PubMed

    Shirato, Ken; Imaizumi, Kazuhiko

    2014-01-01

    The intensities of macrophage inflammatory responses to bacterial components gradually decrease with age. Given that a reduced rate of protein synthesis is a common age-related biochemical change, which is partially mediated by increased phosphorylation of eukaryotic initiation factor-2 α (eIF-2 α ), we investigated the mechanism responsible for the deterioration of macrophage inflammatory responses, focusing specifically on the age-related biochemical changes in middle-aged mice. Peritoneal macrophages isolated from 2-month-old (young) and 12-month-old (middle-aged) male BALB/c mice were stimulated with lipopolysaccharide (LPS). Although LPS-stimulated secretion of tumor necrosis factor- α (TNF- α ) by the macrophages from middle-aged mice was significantly lower than that from young mice, LPS caused marked increases in levels of TNF- α mRNA in macrophages from middle-aged as well as young mice. Moreover, LPS evoked similar levels of phosphorylation of c-Jun N-terminal kinase (JNK) and nuclear factor- κ B (NF- κ B) in young and middle-aged mice. In contrast, the basal level of phosphorylated eIF-2 α in macrophages from middle-aged mice was higher than that in macrophages from young mice. Salubrinal, an inhibitor of the phosphatase activity that dephosphorylates eIF-2 α , suppressed the LPS-stimulated inflammatory responses in a murine macrophage cell line RAW264.7. These results suggest that posttranscriptional suppression of macrophage inflammatory responses during middle age requires phosphorylation of eIF-2 α . PMID:24808968

  1. The Reflective Learning Continuum: Reflecting on Reflection

    ERIC Educational Resources Information Center

    Peltier, James W.; Hay, Amanda; Drago, William

    2005-01-01

    The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

  2. Age- and gender-related changes in the distribution of osteocalcin in the extracellular matrix of normal male and female bone. Possible involvement of osteocalcin in bone remodeling.

    PubMed Central

    Ingram, R T; Park, Y K; Clarke, B L; Fitzpatrick, L A

    1994-01-01

    With increasing age, bone undergoes changes in remodeling that ultimately compromise the structural integrity of the skeleton. The presence of osteocalcin in bone matrix may alter bone remodeling by promoting osteoclast activity. Whether age- and/or gender-related differences exist in the distribution of osteocalcin within individual bone remodeling units is not known. In this study, we determined the immunohistochemical distribution of osteocalcin in the extracellular matrix of iliac crest bone biopsies obtained from normal male and female volunteers, 20-80 yr old. Four different distribution patterns of osteocalcin within individual osteons were arbitrarily defined as types I, II, III, or IV. The frequency of appearance of each osteon type was determined as a percent of the total osteons per histologic section. The proportion of osteons that stained homogeneously throughout the concentric lamellae (type I) decreased in females and males with increasing age. The proportion of osteons that lack osteocalcin in the matrix immediately adjacent to Haversian canals (type III) increased in females and males with age. Osteons staining intensely in the matrix adjacent to Haversian canals (type II) increased in females and was unchanged in aging males. Osteons that contained osteocalcin-positive resting lines (type IV) increased in bone obtained from males with increasing age but were unchanged in females. Sections of bone immunostained for osteopontin (SPP-I), osteonectin, and decorin did not reveal multiple patterns or alterations in staining with gender or increasing age. We suggest that the morphology of individual bone remodeling units is heterogeneous and the particular morphologic pattern of osteocalcin distribution changes with age and gender. These results suggest that differences in the distribution of osteocalcin in bone matrix may be responsible, in part, for the altered remodeling of bone associated with gender and aging. Images PMID:8132785

  3. [Substrates and possible mechanisms of pineal gland moon-sensory function in context of redusome hypothesis of aging and control of biological time in ontogenesis].

    PubMed

    Ivanov, S V

    2008-01-01

    As a result of comparison of the normative factors on human pineal gland volume (8 age groups, n=411) with similar factors obtained in the days of the moon phase extremes (n=49) the following phenomena have been determined. As a rule all the moon phase extremes, in particular the new moon, are accompanied by an appreciable reduce of pineal gland volume, a sort of systole. These changes depend on the age factor. The results of the research advance indirect arguments for the redusome hypothesis of aging.

  4. Protein kinase Mζ-dependent maintenance of GluA2 at the synapse: a possible target for preventing or treating age-related memory decline?

    PubMed

    Aicardi, Giorgio

    2013-08-01

    Age-related functional alterations in the perforant path projection from the entorhinal cortex to the dentate gyrus (DG) of the hippocampus play a major role in age-related memory impairments, but little is known about the molecular mechanisms responsible for these changes. In a recent interesting study, Hara and colleagues (J Neurosci 2012;32:7336-7344) tested young and aged monkeys on the visual recognition memory test "delayed nonmatching-to-sample" (DNMS). Then they performed electron microscopy immunocytochemistry in the hippocampal DG to determine the subcellular localization of the GluA2 subunit of the glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR) and protein kinase Mζ (PKMζ), which promotes memory storage by regulating GluA2-containing AMPAR trafficking. The results obtained suggest that age-related deficits in visual recognition memory are coupled with impairment in PKMζ-dependent maintenance of GluA2 at the synapse. Together with previous evidence of the critical role of PKMζ in memory consolidation, these data render this enzyme an attractive potential therapeutic target for preventing or treating age-related memory decline, and support the view that the pharmacological manipulation of AMPAR trafficking in the synapses may provide new insights in the search of memory enhancers for aged individuals, including those affected by Alzheimer disease.

  5. Possible causes and consequences of variation in age and size at metamorphosis in flatfishes (pleuronectiformes): An analysis at the individual, population, and species levels

    NASA Astrophysics Data System (ADS)

    Chambers, R. C.; Leggett, W. C.

    Observations on metamorphic ages and sizes in flatfishes are synthesized within a hierarchical framework which ascends from individual to population to species levels. Examples of observations and inferences are given for each level with emphasis on variation among individuals within populations. At the species level, size at metamorphosis ranges from ≈4 to 120 mm and is log-normally distributed. Species-level estimates of ages at metamorphosis from field-collected flatfish are of low resolution if they are derived as the difference between approximate spawning and inferred settling dates. Temperature is the only environmental factor whose effects on metamorphic traits have been evaluated at the population level. Age at metamorphosis increases by more than twofold and metamorphic size is expected to increase slightly as temperature decreases across the viable range. At the individual level, data are available for starry flounder, Platichthys stellatus, and winter flounder, Pseudopleuronectes americanus. Bivariate distributions of metamorphic ages and sizes for these flounders, schematized as metamorphic envelopes, have different locations and orientations, but similar shapes. Metamorphic age has greater within-population variation and is less influenced by parentage than is metamorphic length. Furthermore, maternal contributions to metamorphic traits exceed paternal ones. Effects of metamorphic trait variation on size distributions of young-of-the-year juveniles were evaluated by simulations. In a benign environment lacking mortality bias, the effect of metamorphic age on juvenile size variation was ≈sixfold greater than the effect of metamorphic size. The impact of metamorphic age on juvenile size variation lessened with extension of the spawning interval and with increased duration of juvenile life prior to capture.

  6. A possible role of collagen fibrils in the process of calcification observed in the capsule of the pineal gland in aging rats.

    PubMed

    Humbert, W; Cuisinier, F; Voegel, J C; Pévet, P

    1997-06-01

    The relationship between collagen fibrils and calcified concretions exclusively appearing in the pineal gland of adult/aging rats has been investigated. Deposits of lanthanum, which replace calcium ions are distributed along collagen fibrils with a repeating period of about 70 nm. Calcium has been detected histochemically between collagen bundles surrounding extracellular concretions by means of the pyroantimonate method and by X-ray microanalysis. It is associated with phosphorus. The data presented here suggest that collagen fibrils are involved in the genesis and growth of extracellular concretions located in the connective tissue surrounding the pineal gland of aging rats. PMID:9134857

  7. 3D constraints on a possible deep > 2.5 km massive sulphide mineralization from 2D crooked-line seismic reflection data in the Kristineberg mining area, northern Sweden

    NASA Astrophysics Data System (ADS)

    Malehmir, Alireza; Schmelzbach, Cedric; Bongajum, Emmanuel; Bellefleur, Gilles; Juhlin, Christopher; Tryggvason, Ari

    2009-12-01

    2D crooked-line seismic reflection surveys in crystalline environments are often considered challenging in their processing and interpretation. These challenges are more evident when complex diffraction signals that can originate from out-of-the-plane and a variety of geological features are present. A seismic profile in the Kristineberg mining area in northern Sweden shows an impressive diffraction package, covering an area larger than 25 km 2 in the subsurface at depths greater than 2.5 km. We present here a series of scenarios in which each can, to some extent, explain the nature of this extraordinarily large package of diffractions. Cross-dip analysis, diffraction imaging and modeling, as well as 3D processing of the crooked-line data provided constraints on the interpretation of the diffraction package. Overall, the results indicate that the diffraction package can be associated with at least four main short south-dipping diffractors in a depth range of 2.5-4.5 km. Candidate scenarios for the origin of the diffraction package are: (1) a series of massive sulphide deposits, (2) a series of mafic-ultramafic intrusions, (3) a major shear-zone and (4) multiple contact lithologies. We have also investigated the possible contribution of mode-converted scattered energy in the diffraction package using a modified converted-wave 3D prestack depth migration algorithm with the results indicating that a majority of the diffractions are P-wave diffractions. The 3D prestack migration of the data provided improved images of a series of steeply north-dipping mafic-ultramafic sill intrusions to a depth of about 4 km, where the diffractions appear to focus after the migration. The results and associated interpretations presented in this paper have improved our understanding of this conspicuous package of diffractions and may lead to re-evaluation of the 3D geological model of the Kristineberg mining area.

  8. Location in Cognitive and Residential Space at Age 70 Reflects a Lifelong Trait over Parental and Environmental Circumstances: The Lothian Birth Cohort 1936

    ERIC Educational Resources Information Center

    Johnson, Wendy; Gow, Alan J.; Corley, Janie; Starr, John M.; Deary, Ian J.

    2010-01-01

    Though mental ability tends to be relatively stable throughout the lifespan, many still argue that late life cognitive function largely reflects education, social class, and environmental circumstances. Instead, it may be that early life cognitive function contributes to each of these in turn, as well as to late life cognitive function. This paper…

  9. Ex vivo diffusion tensor MRI reflects microscopic structural remodeling associated with aging and disease progression in normal and cardiomyopathic Syrian hamsters

    PubMed Central

    Li, Wen; Lu, Ming; Banerjee, Suhanti; Zhong, Jia; Ye, Allen; Molter, Joseph; Yu, Xin

    2010-01-01

    Dilated cardiomyopathy (DCM) is a major cause of mortality and morbidity in cardiac patients. Aging is often an ignored etiology of pathological conditions. Quantification of DCM and aging associated cardiac structural remodeling is important in guiding and evaluating therapeutic interventions. Diffusion tensor magnetic resonance imaging (DTMRI) has recently been used for nondestructive characterization of three-dimensional myofiber structure. In this study, we explored the potential of DTMRI in delineating microscopic structural remodeling in aging and DCM hearts. Six month (n = 10) and nine month old (n = 11) DCM (TO-2) hamsters and their age-matched controls (F1β) were characterized. Both aging and DCM hearts showed increased diffusivity and decreased diffusion anisotropy. DTMRI images of DCM hearts also revealed a subgroup of imaging pixels characterized by decreased radial diffusivity and increased FA. The location of these pixels showed qualitative agreement with regions of calcium deposition determined by X-ray CT imaging. Histological analysis confirmed expanded extracellular space in aging and DCM hearts as well as substantial calcium deposition in DCM hearts. These results suggest that DTMRI may provide a noninvasive technique to delineate structural remodeling associated with aging and DCM progression at the tissue and cellular level without the use of an exogenous contrast agent. PMID:19434665

  10. [Growing up in the digital age].

    PubMed

    Huerre, Patrice; Vlachopoulou, Xanthie

    2015-01-01

    Virtual reality is at the heart of our daily lives at every age. The proliferation of screens and their use at an ever earlier age requires reflection on how to give the best possible support to children and teenagers with regard to their modern virtual practices. Health professionals have their role to play in combining their knowledge of these age groups with in-depth understanding of the issues surroundingvirtual realities. PMID:25771593

  11. Delta N-15 of N[sub 2] in air trapped in polar ice - a tracer of gas transport in the firn and a possible constraint on ice age-gas age differences

    SciTech Connect

    Sowers, T.; Bender, M.; Raynaud, D.; Korotkevich, IU.S. CNRS, Lab. de Glaciologie et Geophysique de l'Environnement, St.-Martin-d'Heres Arctic and Antarctic Research Inst., St. Petersburg )

    1992-10-01

    Factors which influence the distribution of air in present-day firn are examined on the basis of the analysis of delta N-15 of trapped N[sub 2] in 12 ice-core samples taken from Greenland and Antarctica, and this information is used to determine how air may have been mixed in glacial firn. The upper and the lower limits of ice-age/gas-age differences (Delta age) are then calculated for the ice core at the Vostok, the Dome C, and the Byrd locations, and the results are compared with previous estimates. Finally, the surface-temperature and CO[sub 2] records from Byrd and Vostok over the last 30,000 years are compared to provide independent means of establishing the best estimates of the Delta age difference for Vostok, and of the nature of gas transport in firn during the last glacial termination. 39 refs.

  12. Possible age-related hearing loss (presbycusis) and corresponding change in echolocation parameters in a stranded Indo-Pacific humpback dolphin.

    PubMed

    Li, Songhai; Wang, Ding; Wang, Kexiong; Hoffmann-Kuhnt, Matthias; Fernando, Nimal; Taylor, Elizabeth A; Lin, Wenzhi; Chen, Jialin; Ng, Timothy

    2013-11-15

    The hearing and echolocation clicks of a stranded Indo-Pacific humpback dolphin (Sousa chinensis) in Zhuhai, China, were studied. This animal had been repeatedly observed in the wild before it was stranded and its age was estimated to be ~40 years. The animal's hearing was measured using a non-invasive auditory evoked potential (AEP) method. Echolocation clicks produced by the dolphin were recorded when the animal was freely swimming in a 7.5 m (width)×22 m (length)×4.8 m (structural depth) pool with a water depth of ~2.5 m. The hearing and echolocation clicks of the studied dolphin were compared with those of a conspecific younger individual, ~13 years of age. The results suggested that the cut-off frequency of the high-frequency hearing of the studied dolphin was ~30-40 kHz lower than that of the younger individual. The peak and centre frequencies of the clicks produced by the older dolphin were ~16 kHz lower than those of the clicks produced by the younger animal. Considering that the older dolphin was ~40 years old, its lower high-frequency hearing range with lower click peak and centre frequencies could probably be explained by age-related hearing loss (presbycusis).

  13. A noninflammatory immune response in aged DNA Aβ42-immunized mice supports its safety for possible use as immunotherapy in AD patients.

    PubMed

    Lambracht-Washington, Doris; Rosenberg, Roger N

    2015-03-01

    Aging in the immune system results in tendency to proinflammatory responses. Intradermal DNA immunization showed Th2 polarized noninflammatory immune responses. We tested here 18-month-old mice which were immunized with Aβ42 peptide, DNA Aβ42 trimer, or 2 different prime boost protocols identical to previous experiments. High Aβ42 antibody levels were found in aged mice which had received peptide immunizations (900 μg/mL plasma), and in mice which had received peptide prime and DNA boost immunizations (500 μg/mL), compared with antibodies in DNA Aβ42 immunized mice with 50 μg/mL. Although we found T-cell proliferation and inflammatory cytokines in mice which had received peptide or prime boost immunization, these were not found in DNA-immunized mice. The results are concordant with proinflammatory responses because of immunosenescence and contraindicate the use of Aβ42 peptide immunizations or prime boost immunization protocols for the use in elderly Alzheimer's disease patients. DNA Aβ42 immunization only on the other hand does lead to effective levels of antibodies without inflammatory cytokine or T-cell responses in the aged animal model tested. PMID:25725942

  14. A noninflammatory immune response in aged DNA Aβ42-immunized mice supports its safety for possible use as immunotherapy in AD patients.

    PubMed

    Lambracht-Washington, Doris; Rosenberg, Roger N

    2015-03-01

    Aging in the immune system results in tendency to proinflammatory responses. Intradermal DNA immunization showed Th2 polarized noninflammatory immune responses. We tested here 18-month-old mice which were immunized with Aβ42 peptide, DNA Aβ42 trimer, or 2 different prime boost protocols identical to previous experiments. High Aβ42 antibody levels were found in aged mice which had received peptide immunizations (900 μg/mL plasma), and in mice which had received peptide prime and DNA boost immunizations (500 μg/mL), compared with antibodies in DNA Aβ42 immunized mice with 50 μg/mL. Although we found T-cell proliferation and inflammatory cytokines in mice which had received peptide or prime boost immunization, these were not found in DNA-immunized mice. The results are concordant with proinflammatory responses because of immunosenescence and contraindicate the use of Aβ42 peptide immunizations or prime boost immunization protocols for the use in elderly Alzheimer's disease patients. DNA Aβ42 immunization only on the other hand does lead to effective levels of antibodies without inflammatory cytokine or T-cell responses in the aged animal model tested.

  15. Aging decreases collagen IV expression in vivo in the dermo-epidermal junction and in vitro in dermal fibroblasts: possible involvement of TGF-β1.

    PubMed

    Feru, Jezabel; Delobbe, Etienne; Ramont, Laurent; Brassart, Bertrand; Terryn, Christine; Dupont-Deshorgue, Aurelie; Garbar, Christian; Monboisse, Jean-Claude; Maquart, Francois-Xavier; Brassart-Pasco, Sylvie

    2016-08-01

    Collagen IV is a major component of the dermo-epidermal junction (DEJ). To study expression of collagen IV upon aging in the DEJ and dermal fibroblasts isolated from the same patients. A model of senescent fibroblasts was developed in order to identify biological compounds that might restore the level of collagen IV. Skin fragments of women (30 to 70 years old) were collected. Localisation of collagen IV expression in the DEJ was studied by immunofluorescence. Fibroblast collagen IV expression was studied by real-time PCR, ELISA, and western blotting. Premature senescence was simulated by exposing fibroblasts to subcytotoxic H2O2 concentrations. Collagen IV decreased in the DEJ and fibroblasts relative to age. TGF-β1 treatment significantly increased collagen IV gene and protein expression in fibroblasts and restored expression in the model of senescence. Addition of TGF-β1-neutralizing antibody to fibroblast cultures decreased collagen IV expression. Taken together, the results suggest that the decrease in collagen IV in the DEJ, relative to age, could be due to a decrease in collagen IV expression by senescent dermal fibroblasts and may involve TGF-β1 signalling. PMID:27124123

  16. (U-Th)/He Age Elevation Profiles from the Adamello Batholith (Southern Alps, Italy): Possible Insights into the Miocene Landscape Development of the European Alps

    NASA Astrophysics Data System (ADS)

    Reverman, R.

    2009-12-01

    Alpine landscapes are developed through the complex interplay between tectonics and climate. However, the nature of this interplay is still poorly understood. Age elevation profiles, especially those for low temperature thermochronometers, provide high resolution near surface exhumation rates. These rates can be used to constrain the rate of surface relief development in response to climatic and/or tectonic events. In this study we present the first apatite (U-TH) /He ages for two vertical profiles from the Adamello batholith (Southern Alps, Italy). These initial ages span the Miocene and suggest at least two periods of accelerated cooling. The Adamello batholith is the largest of the Tertiary intrusions along the Insubric line in the European Alps and is bound by two major faults, the Tonale line and the Giudicarie line. Major river systems within the massif drain south to the Po Plain. This makes it an ideal location to determine the role and magnitude of known tectonic events (Giudicarie phase shortening in the Tortonian) and climatic events (Messinian Salinity crisis and Neogene glaciation) in the recent development of alpine relief. Further work will include 4He/3He analysis, zircon (U-Th)/He dating and apatite fission-track analysis.

  17. How Possibly Do Leisure and Social Activities Impact Mental Health of Middle-Aged Adults in Japan?: An Evidence from a National Longitudinal Survey

    PubMed Central

    Takeda, Fumi; Noguchi, Haruko; Monma, Takafumi; Tamiya, Nanako

    2015-01-01

    Objectives This study aimed to investigate longitudinal relations between leisure and social activities and mental health status, considering the presence or absence of other persons in the activity as an additional variable, among middle-aged adults in Japan. This study used nationally representative data in Japan with a five-year follow-up period. Methods This study focused on 16,642 middle-aged adults, age 50–59 at baseline, from a population-based, six-year panel survey conducted by the Japanese Ministry of Health, Labour and Welfare. To investigate the relations between two leisure activities (‘hobbies or cultural activities’ and ‘exercise or sports’) and four social activities (‘community events’, ‘support for children’, ‘support for elderly individuals’ and ‘other social activities’) at baseline and mental health status at follow-up, multiple logistic regression analysis was used. We also used multiple logistic regression analysis to investigate the association between ways of participating in these activities (‘by oneself’, ‘with others’, or ‘both’ (both ‘by oneself’ and ‘with others’)) at baseline and mental health status at follow-up. Results Involvement in both leisure activity categories, but not in social activities, was significantly and positively related to mental health status in both men and women. Furthermore, in men, both ‘hobbies or cultural activities’ and ‘exercise or sports’ were significantly related to mental health status only when conducted ‘with others’. In women, the effects of ‘hobbies or cultural activities’ on mental health status were no differences regardless of the ways of participating, while the result of ‘exercise or sports’ was same as that in men. Conclusions Leisure activities appear to benefit mental health status among this age group, whereas specific social activities do not. Moreover, participation in leisure activities would be effective especially if

  18. Composite Aging Markers Can Be Used for Quantitative Profiling of Aging.

    PubMed

    Shamir, Lior

    2015-01-01

    In the absence of a single marker that reliably reflects biological aging, or even an exact definition of biological age, compound aging scores that combine multiple aging biomarkers into a single composite aging score can quantitatively reflect the age-related changes over time. If aging is viewed as the broad accumulation of alterations over time, a composite score that reflects numerous diverse aspects of these alterations can be used as a quantitative approximation of aging. Profiling the changes of the composite aging score over time shows variations in the pace of aging at different chronological ages, such that the changes over time show distinct stages separated by a short period of rapid aging. These observations are difficult to explain by molecular entropy or stochastic accumulation of irreparable environmental damage alone, as a process driven solely by entropy or stochasticity is not expected to have signs of distinct stages or leaps in aging. These results are in agreement with some previous observations in other organisms, indicating the possibility of the involvement of pathways in the process of aging. Given this evidence, the contention that aging can be driven also by biological pathways should be considered. PMID:26088420

  19. Age-dependent changes in cocaine sensitivity across early ontogeny in male and female rats: Possible role of dorsal striatal D2High receptors

    PubMed Central

    McDougall, Sanders A.; Eaton, Shannon E.; Mohd-Yusof, Alena; Crawford, Cynthia A.

    2015-01-01

    Rationale Responsiveness to acute psychostimulant administration varies across ontogeny. Objective The purpose of the present study was to determine if age-dependent changes in D2High receptors may be responsible for the ontogeny of cocaine sensitivity in preweanling, adolescent, and adult rats. Methods [3H]-Domperidone/dopamine competition assays were used to determine ontogenetic changes in the proportion of D2High receptors in male and female preweanling [postnatal day (PD) 5, 10, 15, and 20], adolescent (PD 40), and adult rats (PD 80). In the behavioral experiment, responsiveness to cocaine (2.5, 5, 10, or 20 mg/kg) was assessed on PD 20, PD 40, and PD 80 for 60 min. Male and female rats were habituated to the apparatus on the two days prior to testing. Distance traveled data were presented both untransformed and as percent of saline controls. Results Male and female preweanling rats (PD 5–PD 20) had a significantly greater percentage of dorsal striatal D2High receptors than adolescent or adult rats. Likewise, preweanling rats (PD 20) were more sensitive to the behavioral effects of cocaine than the two older age groups. Adolescent and adult rats responded in a generally similar manner, however analysis of the untransformed locomotor activity data suggested that adolescent rats were hyporesponsive to 2.5 and 20 mg/kg cocaine when compared to adults. Conclusions Data from the present study are consistent with the hypothesis that ontogenetic changes in D2High receptors are responsible for age-dependent differences in psychostimulant sensitivity. PMID:25589144

  20. Prevention of age-related endothelial dysfunction by habitual aerobic exercise in healthy humans: possible role of nuclear factor κB.

    PubMed

    Walker, Ashley E; Kaplon, Rachelle E; Pierce, Gary L; Nowlan, Molly J; Seals, Douglas R

    2014-12-01

    Habitual aerobic exercise prevents age-related impairments in endothelium-dependent dilation (EDD). We have hypothesized that the pro-inflammatory transcription factor nuclear factor κB (NF-κB) impairs EDD with sedentary aging, and habitual aerobic exercise prevents this age-related suppression of EDD by NF-κB. To test this hypothesis, we have inhibited NF-κB signalling via oral salsalate administration in healthy older aerobic exercise-trained adults (OT, n=14, 58 ± 2 years), older non-exercising adults (ON, n=16, 61 ± 1 years) and young non-exercising controls (YN, n=8, 23 ± 1 years). Salsalate reduced endothelial cell expression of NF-κB p65 by ~25% in ON (P<0.05) but did not significantly change expression in OT or YN (P>0.05). EDD, assessed by brachial artery flow-mediated dilation (FMD), was improved by salsalate in ON (4.0 ± 0.7% compared with 6.8 ± 0.7%, placebo compared with salsalate, P<0.001) but did not change with salsalate in OT or YN (OT: 7.2 ± 0.7% compared with 7.7 ± 0.6%; YN: 7.6 ± 0.9% compared with 8.1 ± 0.8%; placebo compared with salsalate, P>0.05). Endothelium-independent dilation was not affected by salsalate in any group (P>0.05). In ON, vitamin C infusion improved FMD by ~30% during placebo (P<0.001) but had no affect during salsalate (P>0.05). In OT and YN, vitamin C infusion did not affect FMD during either placebo or salsalate (P>0.05). Salsalate reduced endothelial cell nitrotyrosine content by ~25% and NADPH oxidase p47phox expression by ~30% in ON (P<0.05) but had no effect in OT or YN (P>0.05). Our results suggest that endothelial NF-κB signalling is associated with oxidative stress-related impairment of EDD in healthy non-exercising but not aerobically exercising older adults. This may be a key mechanism by which regular aerobic exercise preserves endothelial function and reduces cardiovascular risk with aging.

  1. Reflected Glory

    ERIC Educational Resources Information Center

    Forster, Colin

    2006-01-01

    The scientific model of how people see things is far removed from children's real-world experience. They know that light is needed in order to see an object, but may not know that light is reflected off the object and some of that light enters the eyes. In this article, the author explores children's understanding of reflection and how to develop…

  2. Update: Interim Guidelines for Health Care Providers Caring for Pregnant Women and Women of Reproductive Age with Possible Zika Virus Exposure - United States, 2016.

    PubMed

    Oduyebo, Titilope; Petersen, Emily E; Rasmussen, Sonja A; Mead, Paul S; Meaney-Delman, Dana; Renquist, Christina M; Ellington, Sascha R; Fischer, Marc; Staples, J Erin; Powers, Ann M; Villanueva, Julie; Galang, Romeo R; Dieke, Ada; Muñoz, Jorge L; Honein, Margaret A; Jamieson, Denise J

    2016-02-12

    CDC has updated its interim guidelines for U.S. health care providers caring for pregnant women during a Zika virus outbreak (1). Updated guidelines include a new recommendation to offer serologic testing to asymptomatic pregnant women (women who do not report clinical illness consistent with Zika virus disease) who have traveled to areas with ongoing Zika virus transmission. Testing can be offered 2-12 weeks after pregnant women return from travel. This update also expands guidance to women who reside in areas with ongoing Zika virus transmission, and includes recommendations for screening, testing, and management of pregnant women and recommendations for counseling women of reproductive age (15-44 years). Pregnant women who reside in areas with ongoing Zika virus transmission have an ongoing risk for infection throughout their pregnancy. For pregnant women with clinical illness consistent with Zika virus disease,* testing is recommended during the first week of illness. For asymptomatic pregnant women residing in areas with ongoing Zika virus transmission, testing is recommended at the initiation of prenatal care with follow-up testing mid-second trimester. Local health officials should determine when to implement testing of asymptomatic pregnant women based on information about levels of Zika virus transmission and laboratory capacity. Health care providers should discuss reproductive life plans, including pregnancy intention and timing, with women of reproductive age in the context of the potential risks associated with Zika virus infection.

  3. Decreased cerebrospinal fluid levels of neurosin (KLK6), an aging-related protease, as a possible new risk factor for Alzheimer's disease.

    PubMed

    Mitsui, Shinichi; Okui, Akira; Uemura, Hidetoshi; Mizuno, Toshiki; Yamada, Tatsuo; Yamamura, Yoshio; Yamaguchi, Nozomi

    2002-11-01

    Neurosin is a kallikrein-like serine protease expressed preferentially in the human brain. It is localized in senile plaques and neurofibrillary tangles in the brains of individuals with Alzheimer's disease (AD) and in Lewy bodies in patients with Parkinson's disease. Neurosin is present in the cerebrospinal fluid (CSF) as a proenzyme and does not show any enzymatic activity. We have developed a sandwich ELISA system using monoclonal and polyclonal antibodies against human neurosin and have measured neurosin levels in the CSF from AD and non-CNS disease patients. Both male and female patients with peripheral neuropathy showed statistically positive correlations between CSF neurosin concentrations and age (males, n = 52, r = 0.482, p < 0.005; females, n = 43, r = 0.365, p < 0.005). In contrast, such positive correlation was not observed in the CSF from patients with AD. Further, some such patients showed extremely low levels of CSF neurosin. Our results suggest that neurosin is an aging-related protease and that a decreased CSF concentration of neurosin may be a risk factor for developing AD.

  4. Age-Associated Weight Gain, Leptin, and SIRT1: A Possible Role for Hypothalamic SIRT1 in the Prevention of Weight Gain and Aging through Modulation of Leptin Sensitivity

    PubMed Central

    Sasaki, Tsutomu

    2015-01-01

    The hypothalamus is the principal regulator of body weight and energy balance. It modulates both energy intake and energy expenditure by sensing the energy status of the body through neural inputs from the periphery as well as direct humoral inputs. Leptin, an adipokine, is one of the humoral factors responsible for alerting the hypothalamus that enough energy is stored in the periphery. Plasma leptin levels are positively linked to adiposity; leptin suppress energy intake and stimulates energy expenditure. However, prolonged increases in plasma leptin levels due to obesity cause leptin resistance, affecting both leptin access to hypothalamic neurons and leptin signal transduction within hypothalamic neurons. Decreased sensing of peripheral energy status through leptin may lead to a positive energy balance and gradual gains in weight and adiposity, further worsening leptin resistance. Leptin resistance, increased adiposity, and weight gain are all associated with aging in both humans and animals. Central insulin resistance is associated with similar observations. Therefore, improving the action of humoral factors in the hypothalamus may prevent gradual weight gain, especially during middle age. SIRT1 is a NAD+-dependent protein deacetylase with numerous substrates, including histones, transcription factors, co-factors, and various enzymes. SIRT1 improves both leptin sensitivity and insulin sensitivity by decreasing the levels of several molecules that impair leptin and insulin signal transduction. SIRT1 and NAD+ levels decrease with age in the hypothalamus; increased hypothalamic SIRT1 levels prevent age-associated weight gain and improve leptin sensitivity in mice. Therefore, preventing the age-dependent loss of SIRT1 function in the hypothalamus could improve the action of humoral factors in the hypothalamus as well as central regulation of energy balance. PMID:26236282

  5. [Possibilities for modifying risk factors for chromosome abnormalities--advantages of the so-called "triple" marker studies in comparison with pure "maternal age screening"].

    PubMed

    Holzgreve, W; Schloo, R; Veress, L; Schlegel, W; Tercanli, S; Schneider, H P

    1994-01-01

    We have offered the so-called "triple-marker screening" since May 1991 to all patients who came for prenatal care and did not select an invasive procedure primarily. First evaluation of 5210 cases revealed that 3.7% were test-positive for neural tube defects, 13.8% for Down's syndrome and 0.5% for both at the same time. The explanation for the comparatively high "test-positive" rate of 13.5% is the maternal age distribution with the median at 31.4 years. The highest number of women selecting triple-marker determinations was in the age group of 35 years. We detected 16 cases of Down's syndrome and in this group the majority of women was below 35 years. The decision of women to have an invasive procedure was obviously very much influenced by the actual risk assessment, because amniocentesis was chosen by 72/85 (84.8%) of women with a risk of more than 1:50, 192/290 (66.2%) of women in the risk category of 1:51 to 1:200 and 182/333 (54.6%) in the risk category of 1:201 to 1:400. The follow-up is not yet complete, but there is already good evidence for the efficiency of the screening program. Triple-marker screening also proved predictive in 10 cases of trisomy 18 and 8 cases of triploidy in this series. As a cut-off value we chose the risk of 1:386 which is equivalent to the odds of a 35 year old to have a child with Down's syndrome at birth.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7871918

  6. Reflecting on Reflecting on Practice

    ERIC Educational Resources Information Center

    Wilson, Arthur L.

    2009-01-01

    This article discusses three broad themes--reflection, power, and negotiation--that are evidenced in all of the articles in this issue. In this article, the author tries to transgress the articles at some middling altitude to seek some broader thematics. His observations about reflection, power, and negotiation do transcend individual efforts,…

  7. Radar reflectivity

    NASA Astrophysics Data System (ADS)

    1986-07-01

    This TOP describes a method for measuring the radar reflectivity characteristics of aircraft. It uses a rotating platform and various radar systems to obtain calibrated radar Automatic Gain Control values for each degree of aspect angle for the aircraft. The purpose of this test is to provide comparable values of radar reflectivity for Army aircraft at various radar frequencies and parameter for fixed positions and aspect angles on the aircraft. Data collected on each specific aircraft can be used to evaluate radar reflectivity characteristics of aircraft skin material, paint, and structural changes such as flat versus curved surfaces.

  8. Accretionary Complexes: Recorders of Plate Tectonism and Environmental Conditions Through Time on Earth and Possibly Those Early Noachian (Hadean-equivalent) in Age on Mars

    NASA Astrophysics Data System (ADS)

    Dohm, J. M.; Maruyama, S.; Miyamoto, H.; Viviano-Beck, C. E.; Anderson, R. C.

    2014-12-01

    On Earth, highlighted in Japan, North America, Europe, and Greenland, accretionary complexes comprehensively record information compiled while the oceanic crust is en route from the mid-oceanic ridge to the subduction zone, spanning hundreds of millions of years. At the zone, oceanic crustal materials are stacked along thrust faults and/or subducted to be eventually recycled into the mantle. The surviving accretionary-complex materials include Ocean Plate Stratigraphy (OPS). The ideal succession of the OPS (from oldest to youngest) is mid-ocean ridge basalt, pelagic sediment including radiolarian chert, hemipelagic sediment including siliceous shale, and trench turbidite deposits. Therefore, accretionary complexes often record diverse environmental conditions from deep- to shallow-marine environments, including those perturbed by magmatic, impact, and possibly extrasolar events. Stratigraphic, impact-crater, paleotectonic, and magnetic-anomaly information point to Early Noachian (Hadean-equivalent) Martian geologic terrains; they are extremely ancient environmental records compared to those destroyed on Earth due to differences in planetary mass and evolutional states. Such record a dynamic phase of the evolution of Mars, including interacting ocean, landmass, and atmosphere, as well as possible plate tectonism during an operating dynamo. A candidate accretionary complex and nearby outcrops of steeply dipping beds comprising olistostrome-like blocks, nearby and in the Claritas rise, respectively, may be key evidence of major crustal shortening related to plate tectonism, in addition to being extremely ancient environmental records. Claritas rise is a rugged promontory about 250 km across, which forms the northwest part of an extremely ancient and large mountain range, Thaumasia highlands, with a length nearing 2,400 km, or approximating that of the Himalayas. Future investigation of the ancient Martian basement, which includes geochemical analyses for possible OPS

  9. Petrology, geochemistry, and age of low-Ti mare-basalt meteorite Northeast Africa 003-A: A possible member of the Apollo 15 mare basaltic suite

    NASA Astrophysics Data System (ADS)

    Haloda, Jakub; Týcová, Patricie; Korotev, Randy L.; Fernandes, Vera A.; Burgess, Ray; Thöni, Martin; Jelenc, Monika; Jakeš, Petr; Gabzdyl, Pavel; Košler, Jan

    2009-06-01

    C/h) suggest that the parent melt of NEA 003-A crystallized in the lower part of a lava flow containing cumulate olivine (˜10%) and was probably derived from more primitive picritic magma by fractional crystallization processes. Sm-Nd dating yields an age of 3.09 ± 0.06 Ga which corresponds to the period of lower Eratosthenian lunar volcanic activity, and the near-chondritic ɛNd value of -0.4 ± 0.3 indicates that the meteorite could be derived from a slightly enriched mantle source similar to the Apollo 15 green glasses. Ar-Ar step release results are inconsistent with Sm-Nd ages suggesting that NEA 003-A was exposed to one or more impact events. The most extensive event took place at 1.8 Ga and the shock intensity was likely between 28 and 45 GPa. The absence of solar Ar suggests that NEA 003-A has not been directly exposed at the lunar surface but the cosmic ray exposure age of 209 ± 6 Ma suggests that NEA 003-A resided in the upper regolith for part of its history.

  10. Clearance of autophagy-associated dying retinal pigment epithelial cells – a possible source for inflammation in age-related macular degeneration

    PubMed Central

    Szatmári-Tóth, M; Kristóf, E; Veréb, Z; Akhtar, S; Facskó, A; Fésüs, L; Kauppinen, A; Kaarniranta, K; Petrovski, G

    2016-01-01

    Retinal pigment epithelial (RPE) cells can undergo different forms of cell death, including autophagy-associated cell death during age-related macular degeneration (AMD). Failure of macrophages or dendritic cells (DCs) to engulf the different dying cells in the retina may result in the accumulation of debris and progression of AMD. ARPE-19 and primary human RPE cells undergo autophagy-associated cell death upon serum depletion and oxidative stress induced by hydrogen peroxide (H2O2). Autophagy was revealed by elevated light-chain-3 II (LC3-II) expression and electron microscopy, while autophagic flux was confirmed by blocking the autophago-lysosomal fusion using chloroquine (CQ) in these cells. The autophagy-associated dying RPE cells were engulfed by human macrophages, DCs and living RPE cells in an increasing and time-dependent manner. Inhibition of autophagy by 3-methyladenine (3-MA) decreased the engulfment of the autophagy-associated dying cells by macrophages, whereas sorting out the GFP-LC3-positive/autophagic cell population or treatment by the glucocorticoid triamcinolone (TC) enhanced it. Increased amounts of IL-6 and IL-8 were released when autophagy-associated dying RPEs were engulfed by macrophages. Our data suggest that cells undergoing autophagy-associated cell death engage in clearance mechanisms guided by professional and non-professional phagocytes, which is accompanied by inflammation as part of an in vitro modeling of AMD pathogenesis. PMID:27607582

  11. Subjective Sleep Quality as a Possible Mediator in the Relationship between Personality Traits and Depressive Symptoms in Middle-Aged Adults.

    PubMed

    Huang, Vivian; Peck, Katlyn; Mallya, Sasha; Lupien, Sonia J; Fiocco, Alexandra J

    2016-01-01

    This study explored the mediating role of sleep in the relationship between personality traits and depressive symptoms in a group of community-dwelling men and women (Mage = 57.92, SD = 4.00). Participants completed the short form NEO Five Factor Inventory (NEO-FFI), Pittsburgh Sleep Quality Index (PSQI), and the Center for Epidemiologic Studies Depression Scale (CES-D). High neuroticism and low conscientiousness was associated with poor sleep, as well as greater depressive symptom severity. Partial indirect mediation effects were found between personality traits (i.e., neuroticism and conscientiousness) and depressive symptoms through self-report sleep measures. An alternative model was also explored, entering depression as the mediator; however a smaller portion of the variance was explained by this model, compared with the hypothesized model. The current study provides preliminary information regarding the mechanisms that influence the relationship between personality traits, sleep, and depression among a group of community-dwelling middle-aged adults. Implications and future directions are discussed. PMID:27285159

  12. Clearance of autophagy-associated dying retinal pigment epithelial cells - a possible source for inflammation in age-related macular degeneration.

    PubMed

    Szatmári-Tóth, M; Kristóf, E; Veréb, Z; Akhtar, S; Facskó, A; Fésüs, L; Kauppinen, A; Kaarniranta, K; Petrovski, G

    2016-01-01

    Retinal pigment epithelial (RPE) cells can undergo different forms of cell death, including autophagy-associated cell death during age-related macular degeneration (AMD). Failure of macrophages or dendritic cells (DCs) to engulf the different dying cells in the retina may result in the accumulation of debris and progression of AMD. ARPE-19 and primary human RPE cells undergo autophagy-associated cell death upon serum depletion and oxidative stress induced by hydrogen peroxide (H2O2). Autophagy was revealed by elevated light-chain-3 II (LC3-II) expression and electron microscopy, while autophagic flux was confirmed by blocking the autophago-lysosomal fusion using chloroquine (CQ) in these cells. The autophagy-associated dying RPE cells were engulfed by human macrophages, DCs and living RPE cells in an increasing and time-dependent manner. Inhibition of autophagy by 3-methyladenine (3-MA) decreased the engulfment of the autophagy-associated dying cells by macrophages, whereas sorting out the GFP-LC3-positive/autophagic cell population or treatment by the glucocorticoid triamcinolone (TC) enhanced it. Increased amounts of IL-6 and IL-8 were released when autophagy-associated dying RPEs were engulfed by macrophages. Our data suggest that cells undergoing autophagy-associated cell death engage in clearance mechanisms guided by professional and non-professional phagocytes, which is accompanied by inflammation as part of an in vitro modeling of AMD pathogenesis. PMID:27607582

  13. Subjective Sleep Quality as a Possible Mediator in the Relationship between Personality Traits and Depressive Symptoms in Middle-Aged Adults

    PubMed Central

    Peck, Katlyn; Mallya, Sasha; Lupien, Sonia J.

    2016-01-01

    This study explored the mediating role of sleep in the relationship between personality traits and depressive symptoms in a group of community-dwelling men and women (Mage = 57.92, SD = 4.00). Participants completed the short form NEO Five Factor Inventory (NEO-FFI), Pittsburgh Sleep Quality Index (PSQI), and the Center for Epidemiologic Studies Depression Scale (CES-D). High neuroticism and low conscientiousness was associated with poor sleep, as well as greater depressive symptom severity. Partial indirect mediation effects were found between personality traits (i.e., neuroticism and conscientiousness) and depressive symptoms through self-report sleep measures. An alternative model was also explored, entering depression as the mediator; however a smaller portion of the variance was explained by this model, compared with the hypothesized model. The current study provides preliminary information regarding the mechanisms that influence the relationship between personality traits, sleep, and depression among a group of community-dwelling middle-aged adults. Implications and future directions are discussed. PMID:27285159

  14. Being as Normal as Possible: How Young People Ages 16–25 Years Evaluate the Risks and Benefits of Treatment for Inflammatory Arthritis

    PubMed Central

    McDonagh, Janet E.; Thompson, Ben; Foster, Helen E.; Kay, Lesley; Myers, Andrea; Rapley, Tim

    2016-01-01

    Objective To explore how young people (ages 16–25 years) with inflammatory arthritis evaluate the risks and benefits of treatment, particularly treatment with biologic therapies. Methods This qualitative study involved in‐depth interviews (n = 44) with young people, trusted others (e.g., parents), and health professionals; audio‐recordings (n = 4) of biologic therapy–related consultations; and focus groups (n = 4). Analysis used techniques from grounded theory (open and focused coding, constant comparison, memoing, and mapping). Results Young people aspired to live what they perceived as a “normal” life. They saw treatment as presenting both an opportunity for and a threat to achieving this. Treatment changes were therefore subject to complex and ongoing evaluation, covering administration, associated restrictions, anticipated effects, and side effects. Information sources included expert opinion (of professionals and other patients) and personal experience. Previous treatments provided important reference points. Faced with uncertain outcomes, young people made provisional decisions. Both trusted others and health professionals expressed concern that young people were too focused on short‐term outcomes. Conclusion Young people value treatment that helps them to live a “normal” life. There is more to this than controlling disease. The emotional, social, and vocational consequences of treatment can be profound and lasting: opportunities to discuss the effects of treatment should be provided early and regularly. While making every effort to ensure understanding of the long‐term clinical consequences of taking or not taking medication, the wider impact of treatment should not be dismissed. Only through understanding young people's values, preferences, and concerns can a sustainable balance between disease control and treatment burden be achieved. PMID:27040737

  15. Puerarin suppresses AGEs-induced inflammation in mouse mesangial cells: A possible pathway through the induction of heme oxygenase-1 expression

    SciTech Connect

    Kim, Ki Mo; Jung, Dong Ho; Jang, Dae Sik; Kim, Young Sook; Kim, Jong Min; Kim, Ha-Na; Surh, Young-Joon; Kim, Jin Sook

    2010-04-15

    Puerarin is a natural product isolated from Puerarin lobata and has various pharmacological effects, including anti-hyperglycemic and anti-allergic properties. In the present study, we investigated the effect of puerarin against advanced glycation end products (AGEs)-induced inflammation in mouse mesangial cells. Puerarin acts by inducing the expression of heme oxygenase-1 (HO-1) in a dose- and time-dependent manner. Puerarin was able to enhance phosphorylation of protein kinase C (PKC) delta, but not PKC alpha/beta II, in a time-dependent manner. Induction of HO-1 expression by puerarin was suppressed by GF109203X, a general inhibitor of PKC, and by rottlerin, a specific inhibitor of PKC delta. However, induction was not suppressed by Goe6976, a selective inhibitor for PKC alpha/beta II. Additionally, the knockdown of endogenous PKC delta by small interfering RNA (siRNA) resulted in the inhibition of HO-1 expression and Akt phosphorylation. Puerarin increased antioxidant response element (ARE)-Luciferase activity in a dose- and time-dependent manner in transfected mouse mesangial cells. Mutation of the ARE sequence abolished puerarin-induced HO-1 expression. Furthermore, puerarin treatments resulted in a marked increase in NF-E2 related factor-2 (Nrf-2) translocation, leading to up-regulation of HO-1 expression. However, transfection of Nrf-2 specific siRNA abolished HO-1 expression. Pretreatment with puerarin inhibited the expressions of COX-2, MMP-2 and MMP-9. But, these effects were reversed by ZnPP, an inhibitor of HO-1. Taken together, our results demonstrate that puerarin-induced expression of HO-1 is mediated by the PKC delta-Nrf-2-HO-1 pathway and inhibits N-carboxymethyllysine (CML)-induced inflammation in mouse mesangial cells.

  16. Three-micron extinction of the Titan haze in the 250-700 km altitude range: Possible evidence of a particle-aging process

    NASA Astrophysics Data System (ADS)

    Courtin, Régis; Kim, Sang Joon; Bar-Nun, Akiva

    2015-01-01

    Context. The chemical nature of the Titan haze is poorly understood. The investigation carried out by the Cassini-Huygens suite of instruments is bringing new insights into this question. Aims: This work aims at deriving the vertical variation of the spectral structure of the 3.3-3.4 μm absorption feature of the Titan haze from Cassini VIMS solar occultation data recorded between 250 and 700 km altitude. Methods: We computed the transmittance of Titan's atmosphere using a spherical shell model and a radiative transfer code including the influence of CH4, CH3D, and C2H6, as well as the effects of absorption and scattering by the haze particles. We derived the haze extinction from a comparison of the synthetic spectra with the VIMS solar occultation spectra. Results: We find a marked change in the relative amplitudes of the 3.33 and 3.38 μm features, which are characteristic of aromatic (double C=C chains or rings) or aliphatic (single C-C chains) structural groups, respectively. The pseudo-ratio of aromatics to aliphatics (uncorrected for the absolute band strengths) varies from 3.3 ± 1.9 at 580-700 km to 0.9 ± 0.1 at 350-450 km, and is 0.5 ± 0.1 around 250 km. The structural change from the aromatic to the aliphatic type between 580 and 480 km appears to correspond to a spontaneous aging of the particles - a transition between unannealed and hardened particles - while the further decrease of the pseudo-ratio of aromatics to aliphatics below 480 km may be related to the coating of the core particles by condensates such as heavy alkanes. VIMS transmission spectra data are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/573/A21

  17. Aging, frailty and age-related diseases.

    PubMed

    Fulop, T; Larbi, A; Witkowski, J M; McElhaney, J; Loeb, M; Mitnitski, A; Pawelec, G

    2010-10-01

    The concept of frailty as a medically distinct syndrome has evolved based on the clinical experience of geriatricians and is clinically well recognizable. Frailty is a nonspecific state of vulnerability, which reflects multisystem physiological change. These changes underlying frailty do not always achieve disease status, so some people, usually very elderly, are frail without a specific life threatening illness. Current thinking is that not only physical but also psychological, cognitive and social factors contribute to this syndrome and need to be taken into account in its definition and treatment. Together, these signs and symptoms seem to reflect a reduced functional reserve and consequent decrease in adaptation (resilience) to any sort of stressor and perhaps even in the absence of extrinsic stressors. The overall consequence is that frail elderly are at higher risk for accelerated physical and cognitive decline, disability and death. All these characteristics associated with frailty can easily be applied to the definition and characterization of the aging process per se and there is little consensus in the literature concerning the physiological/biological pathways associated with or determining frailty. It is probably true to say that a consensus view would implicate heightened chronic systemic inflammation as a major contributor to frailty. This review will focus on the relationship between aging, frailty and age-related diseases, and will highlight possible interventions to reduce the occurrence and effects of frailty in elderly people. PMID:20559726

  18. Mosaic aging

    PubMed Central

    Walker, Lary C.; Herndon, James G.

    2010-01-01

    Summary Although all multicellular organisms undergo structural and functional deterioration with age, senescence is not a uniform process. Rather, each organism experiences a constellation of changes that reflect the heterogeneous effects of age on molecules, cells, organs and systems, an idiosyncratic pattern that we refer to as mosaic aging. Varying genetic, epigenetic and environmental factors (local and extrinsic) contribute to the aging phenotype in a given individual, and these agents influence the type and rate of functional decline, as well as the likelihood of developing age-associated afflictions such as cardiovascular disease, arthritis, cancer, and neurodegenerative disorders. Identifying key factors that drive aging, clarifying their activities in different systems, and in particular understanding how they interact will enhance our comprehension of the aging process, and could yield insights into the permissive role that senescence plays in the emergence of acute and chronic diseases of the elderly. PMID:20110150

  19. Reflections on the theory of "silver bullet" octreotide tracers: implications for ligand-receptor interactions in the age of peptides, heterodimers, receptor mosaics, truncated receptors, and multifractal analysis

    PubMed Central

    2011-01-01

    The classical attitude of Nuclear Medicine practitioners on matters of peptide-receptor interactions has maintained an intrinsic monogamic character since many years. New advances in the field of biochemistry and even in clinical Nuclear Medicine have challenged this type of thinking, which prompted me to work on this review. The central issue of this paper will be the use of somatostatin analogs, i.e., octreotide, in clinical imaging procedures as well as in relation to neuroendocirne tumors. Newly described characteristics of G-protein coupled receptors such as the formation of receptor mosaics will be discussed. A small section will enumerate the regulatory processes found in the cell membrane. Possible new interpretations, other than tumor detection, based on imaging procedures with somatostatin analogs will be presented. The readers will be taken to situations such as inflammation, nociception, mechanosensing, chemosensing, fibrosis, taste, and vascularity where somatostatin is involved. Thyroid-associated orbitopathy will be used as a model for the development of multi-agent therapeutics. The final graphical summary depicts the multifactorial properties of ligand binding. PMID:22214590

  20. Possible people.

    PubMed

    Hare, R M

    1988-10-01

    Where we have a choice between bringing someone into existence and not doing so, the interests of the possible person must be considered. The implications of this view for population policy are explored, concluding with a version of utilitarianism that proposes increasing the population of a society while increasing the total utility, without altering its proportionate distribution, until the lowest segment of the population comes below the break-even point at which life is just worth living. Questions of whether poverty is the chief cause of misery and how great an obligation is owed to reducing social and economic inequalities are examined.

  1. Selectively reflective transparent sheets

    NASA Astrophysics Data System (ADS)

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  2. Disc reflection and a possible disc wind during a soft X-ray state in the neutron star low-mass X-ray binary 1RXS J180408.9-342058

    NASA Astrophysics Data System (ADS)

    Degenaar, N.; Altamirano, D.; Parker, M.; Miller-Jones, J. C. A.; Miller, J. M.; Heinke, C. O.; Wijnands, R.; Ludlam, R.; Parikh, A.; Hessels, J. W. T.; Gusinskaia, N.; Deller, A. T.; Fabian, A. C.

    2016-10-01

    1RXS J180408.9-342058 is a transient neutron star low-mass X-ray binary that exhibited a bright accretion outburst in 2015. We present NuSTAR, Swift, and Chandra observations obtained around the peak brightness of this outburst. The source was in a soft X-ray spectral state and displayed an X-ray luminosity of LX ≃ (2-3) × 1037(D/5.8 kpc)2 erg s-1 (0.5-10 keV). The NuSTAR data reveal a broad Fe-K emission line that we model as relativistically broadened reflection to constrain the accretion geometry. We found that the accretion disc is viewed at an inclination of i ≃ 27°-35° and extended close to the neutron star, down to Rin ≃ 5-7.5 gravitational radii (≃11-17 km). This inner disc radius suggests that the neutron star magnetic field strength is B ≲ 2 × 108 G. We find a narrow absorption line in the Chandra/HEG data at an energy of ≃7.64 keV with a significance of ≃4.8σ. This feature could correspond to blueshifted Fe XXVI and arise from an accretion disc wind, which would imply an outflow velocity of vout ≃ 0.086c (≃25 800 km s-1). However, this would be extreme for an X-ray binary and it is unclear if a disc wind should be visible at the low inclination angle that we infer from our reflection analysis. Finally, we discuss how the X-ray and optical properties of 1RXS J180408.9-342058 are consistent with a relatively small (Porb ≲ 3 h) binary orbit.

  3. Haitian reflections.

    PubMed

    Docrat, Fathima

    2010-08-01

    Natural disasters and acts of terrorism demonstrate a similar critical need for national preparedness. As one of a team of volunteers with a local South African NGO who recently went on a medical mission, I would like to share glimpses of our experience and reflect on the mistakes - and also to state the obvious: that we do not learn from our mistakes. A simple literature search has shown that the same mistakes happen repeatedly. 'Humanitarian disasters occur with frightening regularity, yet international responses remain fragmented, with organizations and responders being forced to "reinvent the wheel" with every new event'. This is the result of an obvious lack of preparedness.

  4. Reflective Packaging

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The aluminized polymer film used in spacecraft as a radiation barrier to protect both astronauts and delicate instruments has led to a number of spinoff applications. Among them are aluminized shipping bags, food cart covers and medical bags. Radiant Technologies purchases component materials and assembles a barrier made of layers of aluminized foil. The packaging reflects outside heat away from the product inside the container. The company is developing new aluminized lines, express mailers, large shipping bags, gel packs and insulated panels for the building industry.

  5. Cold-induced thermoregulation and biological aging.

    PubMed

    Florez-Duquet, M; McDonald, R B

    1998-04-01

    Aging is associated with diminished cold-induced thermoregulation (CIT). The mechanisms accounting for this phenomenon have yet to be clearly elucidated but most likely reflect a combination of increased heat loss and decreased metabolic heat production. The inability of the aged subject to reduce heat loss during cold exposure is associated with diminished reactive tone of the cutaneous vasculature and, to a lesser degree, alterations in the insulative properties of body fat. Cold-induced metabolic heat production via skeletal muscle shivering thermogenesis and brown adipose tissue nonshivering thermogenesis appears to decline with age. Few investigations have directly linked diminished skeletal muscle shivering thermogenesis with the age-related reduction in cold-induced thermoregulatory capacity. Rather, age-related declines in skeletal muscle mass and metabolic activity are cited as evidence for decreased heat production via shivering. Reduced mass, GDP binding to brown fat mitochondria, and uncoupling protein (UCP) levels are cited as evidence for attenuated brown adipose tissue cold-induced nonshivering thermogenic capacity during aging. The age-related reduction in brown fat nonshivering thermogenic capacity most likely reflects altered cellular signal transduction rather than changes in neural and hormonal signaling. The discussion in this review focuses on how alterations in CIT during the life span may offer insight into possible mechanisms of biological aging. Although the preponderance of evidence presented here demonstrates that CIT declines with chronological time, the mechanism reflecting this attenuated function remains to be elucidated. The inability to draw definitive conclusions regarding biological aging and CIT reflects the lack of a clear definition of aging. It is unlikely that the mechanisms accounting for the decline in cold-induced thermoregulation during aging will be determined until biological aging is more precisely defined. PMID

  6. Cold-induced thermoregulation and biological aging.

    PubMed

    Florez-Duquet, M; McDonald, R B

    1998-04-01

    Aging is associated with diminished cold-induced thermoregulation (CIT). The mechanisms accounting for this phenomenon have yet to be clearly elucidated but most likely reflect a combination of increased heat loss and decreased metabolic heat production. The inability of the aged subject to reduce heat loss during cold exposure is associated with diminished reactive tone of the cutaneous vasculature and, to a lesser degree, alterations in the insulative properties of body fat. Cold-induced metabolic heat production via skeletal muscle shivering thermogenesis and brown adipose tissue nonshivering thermogenesis appears to decline with age. Few investigations have directly linked diminished skeletal muscle shivering thermogenesis with the age-related reduction in cold-induced thermoregulatory capacity. Rather, age-related declines in skeletal muscle mass and metabolic activity are cited as evidence for decreased heat production via shivering. Reduced mass, GDP binding to brown fat mitochondria, and uncoupling protein (UCP) levels are cited as evidence for attenuated brown adipose tissue cold-induced nonshivering thermogenic capacity during aging. The age-related reduction in brown fat nonshivering thermogenic capacity most likely reflects altered cellular signal transduction rather than changes in neural and hormonal signaling. The discussion in this review focuses on how alterations in CIT during the life span may offer insight into possible mechanisms of biological aging. Although the preponderance of evidence presented here demonstrates that CIT declines with chronological time, the mechanism reflecting this attenuated function remains to be elucidated. The inability to draw definitive conclusions regarding biological aging and CIT reflects the lack of a clear definition of aging. It is unlikely that the mechanisms accounting for the decline in cold-induced thermoregulation during aging will be determined until biological aging is more precisely defined.

  7. Deep seismic reflection profiling and continental growth curves

    NASA Technical Reports Server (NTRS)

    Klemperer, Simon L.

    1988-01-01

    The results of deep seismic reflection profiling is discussed which shows that the lower crust is prominently layered, in many continental areas, regardless of the age of the surface rocks. The seismic Moho is commonly shallower than the petrological Moho, leading to the question of the nature and origin of this prominent reflector in the deep crust. The lower crust is much less well defined in Phanerozoic and Proterozoic accreted terranes, suggesting possible differences in types of lower crusts.

  8. Reflected Glory

    NASA Astrophysics Data System (ADS)

    2011-02-01

    The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO's Hidden Treasures 2010 astrophotography competition with his image of this stunning object. Messier 78 is a fine example of a reflection nebula. The ultraviolet radiation from the stars that illuminate it is not intense enough to ionise the gas to make it glow - its dust particles simply reflect the starlight that falls on them. Despite this, Messier 78 can easily be observed with a small telescope, being one of the brightest reflection nebulae in the sky. It lies about 1350 light-years away in the constellation of Orion (The Hunter) and can be found northeast of the easternmost star of Orion's belt. This new image of Messier 78 from the MPG/ESO 2.2-metre telescope at the La Silla Observatory is based on data selected by Igor Chekalin in his winning entry to the Hidden Treasures competition [1]. The pale blue tint seen in the nebula in this picture is an accurate representation of its dominant colour. Blue hues are commonly seen in reflection nebulae because of the way the starlight is scattered by the tiny dust particles that they contain: the shorter wavelength of blue light is scattered more efficiently than the longer wavelength red light. This image contains many other striking features apart from the glowing nebula. A thick band of obscuring dust stretches across the image from the upper left to the lower right, blocking the light from background stars. In the bottom right corner, many curious pink structures are also visible, which are created by jets of material being ejected from stars that have recently formed and are still buried deep in dust clouds. Two bright stars, HD 38563A and

  9. Reflected Glory

    NASA Astrophysics Data System (ADS)

    2011-02-01

    The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO's Hidden Treasures 2010 astrophotography competition with his image of this stunning object. Messier 78 is a fine example of a reflection nebula. The ultraviolet radiation from the stars that illuminate it is not intense enough to ionise the gas to make it glow - its dust particles simply reflect the starlight that falls on them. Despite this, Messier 78 can easily be observed with a small telescope, being one of the brightest reflection nebulae in the sky. It lies about 1350 light-years away in the constellation of Orion (The Hunter) and can be found northeast of the easternmost star of Orion's belt. This new image of Messier 78 from the MPG/ESO 2.2-metre telescope at the La Silla Observatory is based on data selected by Igor Chekalin in his winning entry to the Hidden Treasures competition [1]. The pale blue tint seen in the nebula in this picture is an accurate representation of its dominant colour. Blue hues are commonly seen in reflection nebulae because of the way the starlight is scattered by the tiny dust particles that they contain: the shorter wavelength of blue light is scattered more efficiently than the longer wavelength red light. This image contains many other striking features apart from the glowing nebula. A thick band of obscuring dust stretches across the image from the upper left to the lower right, blocking the light from background stars. In the bottom right corner, many curious pink structures are also visible, which are created by jets of material being ejected from stars that have recently formed and are still buried deep in dust clouds. Two bright stars, HD 38563A and

  10. Involvement of peroxisome proliferator-activated receptor β/δ (PPAR β/δ) in BDNF signaling during aging and in Alzheimer disease: possible role of 4-hydroxynonenal (4-HNE).

    PubMed

    Benedetti, Elisabetta; D'Angelo, Barbara; Cristiano, Loredana; Di Giacomo, Erica; Fanelli, Francesca; Moreno, Sandra; Cecconi, Francesco; Fidoamore, Alessia; Antonosante, Andrea; Falcone, Roberta; Ippoliti, Rodolfo; Giordano, Antonio; Cimini, Annamaria

    2014-01-01

    Aging and many neurological disorders, such as AD, are linked to oxidative stress, which is considered the common effector of the cascade of degenerative events. In this phenomenon, reactive oxygen species play a fundamental role in the oxidative decomposition of polyunsaturated fatty acids, resulting in the formation of a complex mixture of aldehydic end products, such as malondialdehyde, 4-hydroxynonenal, and other alkenals. Interestingly, 4-HNE has been indicated as an intracellular agonist of peroxisome proliferator-activated receptor β/δ. In this study, we examined, at early and advanced AD stages (3, 9, and 18 months), the pattern of 4-HNE and its catabolic enzyme glutathione S-transferase P1 in relation to the expression of PPARβ/δ, BDNF signaling, as mRNA and protein, as well as on their pathological forms (i.e., precursors or truncated forms). The data obtained indicate a novel detrimental age-dependent role of PPAR β/δ in AD by increasing pro-BDNF and decreasing BDNF/TrkB survival pathways, thus pointing toward the possibility that a specific PPARβ/δ antagonist may be used to counteract the disease progression. PMID:24621497

  11. A Reflective Look at Reflecting Teams

    ERIC Educational Resources Information Center

    Pender, Rebecca L.; Stinchfield, Tracy

    2012-01-01

    This article reviewed existing literature and research on the reflecting team process. There is a dearth of empirical research that explores the reflecting team process and the outcome of counseling that uses reflecting teams. Implications of using reflecting teams for counselors, counselor educators, and clients will be discussed. A call for…

  12. Nondestructive Determination of the Age of 20th-Century Oil-Binder Ink Prints Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FT-IR): A Case Study with Postage Stamps from the Łódź Ghetto.

    PubMed

    Bower, Nathan W; Blanchet, Conor J K; Epstein, Michael S

    2016-01-01

    The ability to determine the production date for a painting or print would be of great benefit in the forensic detection of fakes and forgeries as well as in art history and conservation. Changes in the pigments used at different times have been invaluable in detecting incongruities that suggest fraud, but relatively little work has been published that uses the chemical changes in oil binders as they dry to determine when an ink print or an oil painting was made. Using attenuated total reflectance-Fourier transform infrared (ATR FT-IR) spectroscopy and samples with known dates, we calibrate the drying of oil binders in inks and paints and cross-validate the paints with pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS). We apply the ink calibration to a case study involving the age determination of possible philatelic counterfeits from a World War II Jewish Ghetto in Occupied Poland, obtaining a date of 1946 ± 6 (1 s, n = 9) for the genuine stamps, and 1963 ± 16 (1 s, n = 19) for the various reproductions. PMID:26767642

  13. Reflected Ceiling Plan/Reflected Deck Plan 2009; Reflected Ceiling Plan/Reflected Deck ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Reflected Ceiling Plan/Reflected Deck Plan 2009; Reflected Ceiling Plan/Reflected Deck Plan 2010 - Gilpin's Falls Covered Bridge, Spanning North East Creek at Former (Bypassed) Section of North East Road (SR 272), North East, Cecil County, MD

  14. English Education and Aging.

    ERIC Educational Resources Information Center

    Gillis, Candida

    1983-01-01

    Suggests that English teachers are in an excellent position to help students learn about the aged and aging because they know literature that treats the joys and pains of later life and they understand how language shapes and reflects cultural attitudes. Proposes objectives and presents samples of activities to be used in an aging unit. (MM)

  15. Quality Self-Reflection through Reflection Training

    ERIC Educational Resources Information Center

    Gun, Bahar

    2011-01-01

    This research study discusses the importance of "reflection training" in teacher education programmes. The main premise of the study is that although teachers are constantly encouraged to "reflect" on their teaching, they are unable to do so effectively unless they are specifically trained in how to reflect (they tend to "react" rather than…

  16. Reflections on Reflective Learning in Professional Formation

    ERIC Educational Resources Information Center

    Warhurst, Russell

    2008-01-01

    Reflective learning is a standard and largely unquestioned pedagogy of initial in-service professional education. This case study problematises the processes of reflective learning and examines the constraints on beginning professionals' reflection. The paper outlines a theoretical framework to enable understanding of the nature of reflective…

  17. Orientations to Reflective Practice.

    ERIC Educational Resources Information Center

    Wellington, Bud; Austin, Patricia

    1996-01-01

    Delineates five orientations to reflective practice: immediate, technical, deliberative, dialectic, and transpersonal, each reflecting different social science bases and beliefs and values about education. Views them as interactive, interdependent, noncompeting, aspects of reflective practice. (SK)

  18. Scintillator reflective layer coextrusion

    DOEpatents

    Yun, Jae-Chul; Para, Adam

    2001-01-01

    A polymeric scintillator has a reflective layer adhered to the exterior surface thereof. The reflective layer comprises a reflective pigment and an adhesive binder. The adhesive binder includes polymeric material from which the scintillator is formed. A method of forming the polymeric scintillator having a reflective layer adhered to the exterior surface thereof is also provided. The method includes the steps of (a) extruding an inner core member from a first amount of polymeric scintillator material, and (b) coextruding an outer reflective layer on the exterior surface of the inner core member. The outer reflective layer comprises a reflective pigment and a second amount of the polymeric scintillator material.

  19. Venus: global surface radar reflectivity.

    PubMed

    Pettengill, G H; Ford, P G; Nozette, S

    1982-08-13

    Observations of the surface of Venus, carried out by the Pioneer Venus radar mapper at a wavelength of 17 centimeters, reveal a global mean reflectivity at normal incidence of 0.13 +/- 0.03. Over the surface, variations from a low of 0.03 +/- 0.01 to a high of 0.4 +/- 0.1 are found, with Theia Mons, previously identified as possibly volcanic, showing a value of 0.28 +/- 0.07. Regions of high reflectivity may consist of rocks with substantial inclusions of highly conductive sulfides. PMID:17817535

  20. Reflectivity, Reflexivity and Situated Reflective Practice

    ERIC Educational Resources Information Center

    Malthouse, Richard; Roffey-Barentsen, Jodi; Watts, Mike

    2014-01-01

    This paper describes an aspect of reflective practice referred to as situated reflective practice. The overarching theory is derived from social theories of structuration and reflexivity. In particular, from Giddens' theory of structuration, which sees social life as an interplay of agency and structure. Discussion of the research reported…

  1. Exploring the Possibilities of Technology

    ERIC Educational Resources Information Center

    Fanton, Jonathan F.

    2006-01-01

    Over the last few years, the Board and staff of the MacArthur Foundation have been exploring the implications of the digital age. They are engaged in a continuous and purposeful meditation on technological innovations and their possibilities for all the work they do. Their working hypothesis is that the digital revolution will rank with the…

  2. Planar Reflection of Gaseous Detonations

    NASA Astrophysics Data System (ADS)

    Damazo, Jason Scott

    Pipes containing flammable gaseous mixtures may be subjected to internal detonation. When the detonation normally impinges on a closed end, a reflected shock wave is created to bring the flow back to rest. This study built on the work of Karnesky (2010) and examined deformation of thin-walled stainless steel tubes subjected to internal reflected gaseous detonations. A ripple pattern was observed in the tube wall for certain fill pressures, and a criterion was developed that predicted when the ripple pattern would form. A two-dimensional finite element analysis was performed using Johnson-Cook material properties; the pressure loading created by reflected gaseous detonations was accounted for with a previously developed pressure model. The residual plastic strain between experiments and computations was in good agreement. During the examination of detonation-driven deformation, discrepancies were discovered in our understanding of reflected gaseous detonation behavior. Previous models did not accurately describe the nature of the reflected shock wave, which motivated further experiments in a detonation tube with optical access. Pressure sensors and schlieren images were used to examine reflected shock behavior, and it was determined that the discrepancies were related to the reaction zone thickness extant behind the detonation front. During these experiments reflected shock bifurcation did not appear to occur, but the unfocused visualization system made certainty impossible. This prompted construction of a focused schlieren system that investigated possible shock wave-boundary layer interaction, and heat-flux gauges analyzed the boundary layer behind the detonation front. Using these data with an analytical boundary layer solution, it was determined that the strong thermal boundary layer present behind the detonation front inhibits the development of reflected shock wave bifurcation.

  3. [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

  4. Perfect anti-reflection from first principles

    NASA Astrophysics Data System (ADS)

    Kim, Kyoung-Ho; Q-Han Park

    2013-01-01

    Reducing unwanted reflections through impedance matching, called anti-reflection, has long been an important challenge in optics and electrical engineering. Beyond trial and error optimization, however, a systematic way to realize anti-reflection is still absent. Here, we report the discovery of an analytic solution to this long standing problem. For electromagnetic waves, we find the graded permittivity and permeability that completely remove any given impedance mismatch. We demonstrate that perfect broadband anti-reflection is possible when a dispersive, graded refractive index medium is used for the impedance-matching layer. We also present a design rule for the ultra-thin anti-reflection coating which we confirm experimentally by showing the anti-reflection behavior of an exemplary λ/25-thick coating made of metamaterials. This work opens a new path to anti-reflection applications in optoelectronic device, transmission line and stealth technologies.

  5. Snow reflectance from thematic mapper

    NASA Technical Reports Server (NTRS)

    Dozier, J.

    1983-01-01

    Calculations of snow reflectance in all 6 TM reflective bands (i.e., 1,2,3,4,5, and 7) using a delta Eddington model show that snow reflectance in bands 4,5, and 7 is sensitive to grain size. Efforts to interpret the surface optical grain size for the spectral extension of albedo are described. Results show the TM data include spectral channels suitable for snow/cloud discrimination and for snow albedo measurements that can be extended throughout the solar spectrum. Except for band 1, the dynamic range is large enough that saturation occurs only occasionally. The finer resolution gives much better detail on the snowcovered area and might make it possible to use textural information instead of the snowline as an index to the amount of snow melt runoff.

  6. Reflections in art

    PubMed Central

    CAVANAGH, PATRICK; CHAO, JESSICA; WANG, DINA

    2009-01-01

    When artists depict a mirror in a painting, it necessarily lacks the most obvious property of a mirror: as we move around the painting of the mirror, the reflections we see in it do not change. And yet representations of mirrors and other reflecting surfaces can be quite convincing in paintings. Here, we will examine the rules of reflection, the many ways that painters can break those rules without losing the impression of reflection and the rules that cannot be broken. The rules that govern the perception of reflection are a small subset of the physical rules of reflection. PMID:18534102

  7. Digital Storytelling: Expanding Media Possibilities for Learning

    ERIC Educational Resources Information Center

    McLellan, Hilary, Ed.

    2008-01-01

    Stories offer a powerful framework for engagement, reflection, and other important skills that young people need to learn. As digital media have expanded, so have the possibilities for creating stories. Here, several examples of those new possibilities are examined, examples that highlight student-produced online broadcasting initiatives,…

  8. UV, stress and aging.

    PubMed

    Debacq-Chainiaux, Florence; Leduc, Cedric; Verbeke, Alix; Toussaint, Olivier

    2012-07-01

    Skin is a model of choice in studies on aging. Indeed, skin aging can be modulated by internal and external factors, reflecting its complexity. Two types of skin aging have been identified: intrinsic, mainly genetically determined and extrinsic-also called "photo-aging"-resulting on the impact of environmental stress and more precisely of UV rays. Simplified in vitro models, based on cellular senescence, have been developed to study the relationship between UV and aging. These models vary on the cell type (fibroblasts or keratinocytes, normal or immortalized) and the type of UV used (UVA or UVB). PMID:23467762

  9. UV, stress and aging.

    PubMed

    Debacq-Chainiaux, Florence; Leduc, Cedric; Verbeke, Alix; Toussaint, Olivier

    2012-07-01

    Skin is a model of choice in studies on aging. Indeed, skin aging can be modulated by internal and external factors, reflecting its complexity. Two types of skin aging have been identified: intrinsic, mainly genetically determined and extrinsic-also called "photo-aging"-resulting on the impact of environmental stress and more precisely of UV rays. Simplified in vitro models, based on cellular senescence, have been developed to study the relationship between UV and aging. These models vary on the cell type (fibroblasts or keratinocytes, normal or immortalized) and the type of UV used (UVA or UVB).

  10. Reflection Positivity for Parafermions

    NASA Astrophysics Data System (ADS)

    Jaffe, Arthur; Pedrocchi, Fabio L.

    2015-07-01

    We establish reflection positivity for Gibbs trace states for a class of gauge-invariant, reflection-invariant Hamiltonians describing parafermion interactions on a lattice. We relate these results to recent work in the condensed-matter physics literature.

  11. Age-related responses to mild restraint in the rat.

    PubMed

    Rattner, B A; Michael, S D; Altland, P D

    1983-11-01

    Immature, postpubertal, young adult, and middle-aged rats were lightly restrained for 4 h. Relative to untreated controls, restraint uniformly reduced body weight and plasma luteinizing hormone concentration and elevated plasma corticosterone concentration in all age groups. However, restraint increased activities of plasma alanine and aspartate aminotransferase, creatine phosphokinase, and fructose-diphosphate aldolase in only immature and middle-aged animals. This age-related release of tissue enzymes is hypothesized to reflect enhanced responsiveness to catecholamines in immature rats, and possible ischemia related to diminished vasodilatory activity in middle-aged rats. On the basis of these changes, tolerance to restraint in postpubertal and young adults appears to be slightly greater than that of immature and middle-aged rats.

  12. Neutron reflecting supermirror structure

    DOEpatents

    Wood, J.L.

    1992-12-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

  13. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

  14. Reflective Learning in Practice.

    ERIC Educational Resources Information Center

    Brockbank, Anne, Ed.; McGill, Ian, Ed.; Beech, Nic, Ed.

    This book contains 22 papers on reflective learning in practice. The following papers are included: "Our Purpose" (Ann Brockbank, Ian McGill, Nic Beech); "The Nature and Context of Learning" (Ann Brockbank, Ian McGill, Nic Beech); "Reflective Learning and Organizations" (Ann Brockbank, Ian McGill, Nic Beech); "Reflective Learning in Practice" (Ann…

  15. Liberating Moral Reflection

    ERIC Educational Resources Information Center

    Horell, Harold D.

    2013-01-01

    The author argues that if we are to foster life-giving and liberating moral reflection, we must first liberate moral reflection from distortions; specifically, from the distorting effects of moral insensitivity, destructive moral relativism, and confusions resulting from a failure to understand the dynamics of moral reflection. The author proposes…

  16. Teaching Critical Reflection

    ERIC Educational Resources Information Center

    Smith, Elizabeth

    2011-01-01

    Despite long-standing commitment to the notion of critical reflection across the healthcare professions it is unusual for critical theory and practice to be taught as explicit subjects in healthcare higher education. There is evidence to show that reflective techniques such as critical portfolios and reflective diaries can help students to…

  17. Active Ageing: Intergenerational Relationships and Social Generativity.

    PubMed

    Rossi, Giovanna; Boccacin, Lucia; Bramanti, Donatella; Meda, Stefania G

    2014-01-01

    This contribution is a reflection on the concept of active ageing from the perspective of relational sociology. At the same time, it offers practical implications and outlines possible future courses of action, in the face of demographic and relational scenarios rapidly changing, and the challenges that each day people of all generations are called to cope with. Active ageing is quite a recent concept and indicates an attitude towards ageing that enhances the quality of life as people become older. The goal of active ageing is to enable people to realise their potential for physical, social and mental well-being and to participate in social life also in the last stage of the life cycle. In this phase, the presence of a network of support, security and care adequate to the possible onset of problems and criticalities is crucial. Relational sociology frames the phenomenon of an ageing population in a dense network of social relations, primarily at the level of family and community. For this reason, as supported by the most recent sociological literature and evidence from studies conducted in Italy and abroad (cf. SHARE), it is extremely important to investigate the link between active ageing, intergenerational orientation (solidarity and exchanges) and practices of prosociality (i.e. engagement in third-sector activities and volunteering in later life).

  18. Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population

    PubMed Central

    Mandas, Antonella; Mereu, Rosa Maria; Catte, Olga; Saba, Antonio; Serchisu, Luca; Costaggiu, Diego; Peiretti, Enrico; Caminiti, Giulia; Vinci, Michela; Casu, Maura; Piludu, Stefania; Fossarello, Maurizio; Manconi, Paolo Emilio; Dessí, Sandra

    2014-01-01

    Neurological disorders (Alzheimer’s disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer’s disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer’s disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer’s disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision

  19. Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population.

    PubMed

    Mandas, Antonella; Mereu, Rosa Maria; Catte, Olga; Saba, Antonio; Serchisu, Luca; Costaggiu, Diego; Peiretti, Enrico; Caminiti, Giulia; Vinci, Michela; Casu, Maura; Piludu, Stefania; Fossarello, Maurizio; Manconi, Paolo Emilio; Dessí, Sandra

    2014-01-01

    Neurological disorders (Alzheimer's disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer's disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer's disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer's disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision disorders but

  20. Mapping sea ice using reflected GNSS signals in a bistatic radar system

    NASA Astrophysics Data System (ADS)

    Chew, Clara; Zuffada, Cinzia; Shah, Rashmi; Mannucci, Anthony

    2016-04-01

    Global Navigation Satellite System (GNSS) signals can be used as a kind of bistatic radar, with receivers opportunistically recording ground-reflected signals transmitted by the GNSS satellites themselves. This technique, GNSS-Reflectometry (GNSS-R), has primarily been explored using receivers flown on aircraft or balloons, or in modeling studies. Last year's launch of the TechDemoSat-1 (TDS-1) satellite represents an enormous opportunity to investigate the potential of using spaceborne GNSS receivers to sense changes in the land and ocean surface. Here, we examine the ability of reflected GNSS signals to estimate sea ice extent and sea ice age, as well as comment on the possibility of using GNSS-R to detect leads and polynyas within the ice. In particular, we quantify how the peak power of Delay Doppler Maps (DDMs) generated within the GNSS receiver responds as the satellite flies over the Polar Regions. To compute the effective peak power of each DDM, we first normalize the peak power of the DDM by the noise floor. We also correct for antenna gain, range, and incidence angle. Once these corrections are made, the effective peak power across DDMs may be used as a proxy for changes in surface permittivity and surface roughness. We compare our calculations of reflected power to existing sea ice remote sensing products such as data from the SSMI/S as well as Landsat imagery. Our analysis shows that GNSS reflections are extremely sensitive to the sea ice edge, with increases in reflected power of more than 10 dB relative to reflected power over the open ocean. As the sea ice ages, it thickens and roughens, and reflected power decreases, though it does not decrease below the power over the open ocean. Given the observed sensitivity of GNSS reflections to small features over land and the sensitivity to the sea ice edge, we hypothesize that reflection data could help map the temporal evolution of leads and polynyas.

  1. Worlds of Possibilities in Response to Literature, Film, and Life.

    ERIC Educational Resources Information Center

    Cox, Carole; Many, Joyce E.

    1989-01-01

    Examines the interrelationships between cinematic and literary works in terms of possible responses, or the possible worlds created when children encounter and create literary discourse. Notes that these responses reflect previous encounters with literature, film, and life. (MM)

  2. 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 ...

  3. Weak shock wave reflection from concave surfaces

    NASA Astrophysics Data System (ADS)

    Gruber, Sebastien; Skews, Beric

    2013-07-01

    The reflection of very weak shock waves from concave curved surfaces has not been well documented in the past, and recent studies have shown the possible existence of a variation in the accepted reflection configuration evolution as a shock wave encounters an increasing gradient on the reflecting surface. The current study set out to investigate this anomaly using high-resolution photography. Shock tube tests were done on various concave circular and parabolic geometries, all with zero initial ramp angle. Although the results have limitations due to the achievable image resolution, the results indicate that for very weak Mach numbers, M S < 1.1, there may be a region in which the reflection configuration resembles that of a regular reflection, unlike for the stronger shock wave case. This region exists after the triple point of the Mach reflection meets the reflecting surface and prior to the formation of the additional shock structures that represent a transitioned regular reflection. The Mach and transitioned regular reflections at 1.03 < M s < 1.05 also exhibit no signs of a visible shear layer, or a clear discontinuity at the triple point, and are thus also apparently different in the weak shock regime than what has been described for stronger shocks, similar to what has been shown for weak shocks reflecting off a plane wedge.

  4. Reflections on Reflective Abstractions in Creative Thinking.

    ERIC Educational Resources Information Center

    Cohen, Leonora Marx

    This report proposes a modification of Jean Piaget's concept of "creative abstraction," the mechanism of creative thought, which develops both intelligence and creative ideas. By reflecting on one's actions and the coordinations of actions, the individual constructs new relationships, links, rules, or correspondences between and among them.…

  5. Red and near-infrared spectral reflectance of snow

    NASA Technical Reports Server (NTRS)

    Obrien, H. W.; Munis, R. H.

    1975-01-01

    The spectral reflectance of snow in the range of 0.60 to 2.50 microns wavelengths was studied in a cold laboratory using natural snow and simulated preparations of snow. A white barium sulfate powder was used as the standard for comparison. The high reflectance (usually nearly 100%) of fresh natural snow in visible wavelengths declines rapidly at wavelengths longer than the visible, as the spectral absorption coefficients of ice increase. Aging snow becomes only somewhat less reflective than fresh snow in the visible region and usually retains a reflectance greater than 80%. In the near infrared, aging snow tends to become considerably less reflective than fresh snow.

  6. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, I.J.; Wendt, J.R.

    1994-09-06

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors. 8 figs.

  7. Tandem resonator reflectance modulator

    DOEpatents

    Fritz, Ian J.; Wendt, Joel R.

    1994-01-01

    A wide band optical modulator is grown on a substrate as tandem Fabry-Perot resonators including three mirrors spaced by two cavities. The absorption of one cavity is changed relative to the absorption of the other cavity by an applied electric field, to cause a change in total reflected light, as light reflecting from the outer mirrors is in phase and light reflecting from the inner mirror is out of phase with light from the outer mirrors.

  8. Reflective diffraction grating

    DOEpatents

    Lamartine, Bruce C.

    2003-06-24

    Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

  9. Distinguishing major lithologic types in rocks of precambrian age in central Wyoming using multilevel sensing, with a chapter on possible economic significance of iron formation discovered by use of aircraft images in the Granite Mountains of Wyoming

    NASA Technical Reports Server (NTRS)

    Houston, R. S. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Information obtained by remote sensing from three altitude levels: ERTS-1 (565 miles), U-2 (60,000 feet), and C-130 aircraft (15,000 feet) illustrates the possible application of multilevel sensing in mineral exploration. Distinction can be made between rocks of greenstone belts and rocks of granite-granite gneiss areas by using ERTS-1 imagery in portions of the Precambrian of central Wyoming. Study of low altitude color and color infrared photographs of the mafic terrain revealed the presence of metasedimentary rocks with distinct layers that were interpreted as amphibolite by photogeologic techniques. Some of the amphibolite layers were found to be iron formation when examined in the field. To our knowledge this occurrence of iron formation has not been previously reported in the literature.

  10. Neutron reflecting supermirror structure

    DOEpatents

    Wood, James L.

    1992-01-01

    An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

  11. Dynamic properties of bovine temporomandibular joint disks change with age.

    PubMed

    Tanaka, E; Aoyama, J; Tanaka, M; Murata, H; Hamada, T; Tanne, K

    2002-09-01

    The temporomandibular joint disk exhibits morphological and biochemical age-related changes. However, the possible age-related changes of the dynamic viscoelasticity in the disk are unclear. We tested the hypothesis that the dynamic viscoelastic properties of the disk change with age. Thirty-six disks from young-adult, adult, and mature-adult cattle were used for dynamic tensile tests. In all disks, the magnitudes of the complex modulus, the storage modulus, and the loss modulus increased as the frequency increased. The mature-adult disks had higher values of these moduli than did the younger disks. The loss tangent ranged from 0.1 to 0.3, which means that the disk has relatively large elasticity and relatively small viscosity. It was concluded that both the elasticity and viscosity of the disk increase with age. This may reflect age-related changes in biochemical composition.

  12. Thoughts on the Psycho-biology of Aging

    ERIC Educational Resources Information Center

    Jarvik, Ussy F.

    1975-01-01

    Reflections on psychological perspectives of aging are focused around issues of biological changes and mental functioning, genetic factors in aging, psychological changes with aging, individual differences in mental functioning and the intellectual decline of the aged. (EH)

  13. Persistent Possible Science Selves

    ERIC Educational Resources Information Center

    Mills, Leila A.; Lin, Lin

    2014-01-01

    This paper examines literature on the development of self-knowledge for possible selves--how an individual thinks about oneself and one's potential future selves (Markus & Nurius, 1986). Future science selves research, a recent offshoot of possible selves theories, centers on the development and loss of future possible scientific selves and…

  14. Biochemical markers of aging for longitudinal studies in humans.

    PubMed

    Engelfriet, Peter M; Jansen, Eugène H J M; Picavet, H Susan J; Dollé, Martijn E T

    2013-01-01

    Much progress has been made in the past decades in unraveling the mechanisms that are responsible for aging. The discovery that particular gene mutations in experimental species such as yeast, flies, and nematodes are associated with longevity has led to many important insights into pathways that regulate aging processes. However, extrapolating laboratory findings in experimental species to knowledge that is valid for the complexity of human physiology remains a major challenge. Apart from the restricted experimental possibilities, studying aging in humans is further complicated by the development of various age-related diseases. The availability of a set of biomarkers that really reflect underlying aging processes would be of much value in disentangling age-associated pathology from specific aging mechanisms. In this review, we survey the literature to identify promising biochemical markers of aging, with a particular focus on using them in longitudinal studies of aging in humans that entail repeated measurements on easily obtainable material, such as blood samples. Our search strategy was a 2-pronged approach, one focused on general mechanisms of aging and one including studies on clinical biomarkers of age-related diseases.

  15. Biochemical Markers of Aging for Longitudinal Studies in Humans

    PubMed Central

    Engelfriet, Peter M.; Jansen, Eugène H. J. M.; Picavet, H. Susan J.; Dollé, Martijn E. T.

    2013-01-01

    Much progress has been made in the past decades in unraveling the mechanisms that are responsible for aging. The discovery that particular gene mutations in experimental species such as yeast, flies, and nematodes are associated with longevity has led to many important insights into pathways that regulate aging processes. However, extrapolating laboratory findings in experimental species to knowledge that is valid for the complexity of human physiology remains a major challenge. Apart from the restricted experimental possibilities, studying aging in humans is further complicated by the development of various age-related diseases. The availability of a set of biomarkers that really reflect underlying aging processes would be of much value in disentangling age-associated pathology from specific aging mechanisms. In this review, we survey the literature to identify promising biochemical markers of aging, with a particular focus on using them in longitudinal studies of aging in humans that entail repeated measurements on easily obtainable material, such as blood samples. Our search strategy was a 2-pronged approach, one focused on general mechanisms of aging and one including studies on clinical biomarkers of age-related diseases. PMID:23382477

  16. [The Ability to Successfully Perform Different Kinds of Cognitive Activity Is Reflected in the Topological Features of Intracortical Interactions (Sex Differences in Boys and Girls Aged 5-6 Years)].

    PubMed

    Panasevich, E A; Tsitseroshin, M N

    2015-01-01

    We studied the correlation of intellectual development according to The Wechsler Intelligence Scale for Children (WISC test) with the spatial organization of resting EEG in 52 children aged 5-6 years. It was found that the patterns of interregional interactions of different parts of the cortex which correspond with the best performance in the subtests in boys (n = 23) and girls (n = 29) have significant topological differences. In girls, successful subtest performance positively correlated to a greater extent with interhemispheric interactions; in boys--long longitudinal rostral-caudal interactions between various regions of the cortex. The results showed that there are important gender differences in the spatial organization of brain activity associated with the performance of different cognitive activities in preschool children. The successful performance of various subtests by boys required considerable variability in the organization of spatial patterns of interregional interactions; on the contrary, the spatial structure of these patterns in girls was relatively invariable. Obviously, for the successful performance of various cognitive activities at this age in boys, the cortex need to form highly specialized organization of intracortical interactions, while in girls the brain uses relatively similar reorganization of interactions. The data suggest that 5-6-year-old boys and girls use different cognitive strategies when performing the same subtests of the WISC test.

  17. Transparencies and Reflections.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    1999-01-01

    Discusses the use of perspective, or showing things as the human eye sees them, when creating reflections and transparencies in works of art. Provides examples of artwork using transparency, reflection, and refraction by M. C. Escher, Richard Estes, and Janet Fish to give students an opportunity to learn about these three art techniques. (CMK)

  18. Earth's Reflection: Albedo

    ERIC Educational Resources Information Center

    Gillette, Brandon; Hamilton, Cheri

    2011-01-01

    When viewing objects of different colors, you might notice that some appear brighter than others. This is because light is reflected differently from various surfaces, depending on their physical properties. The word "albedo" is used to describe how reflective a surface is. The Earth-atmosphere has a combined albedo of about 30%, a number that is…

  19. Renewable liquid reflection grating

    DOEpatents

    Ryutov, Dmitri D.; Toor, Arthur

    2003-10-07

    A renewable liquid reflection grating. Electrodes are operatively connected to a conducting liquid in an arrangement that produces a reflection grating and driven by a current with a resonance frequency. In another embodiment, the electrodes create the grating by a resonant electrostatic force acting on a dielectric liquid.

  20. Reflective Writing through the Use of Guiding Questions

    ERIC Educational Resources Information Center

    Moussa-Inaty, Jase

    2015-01-01

    Reflections can be seen as powerful tools for growth and intellectual development. It is no surprise that the writing of reflections is common practice at a Federal Institute in the United Arab Emirates (UAE). The research presented sought to explore possible differences in reflective writing once guidelines were presented to a group of interns in…

  1. Positronium reflection and positronium beams

    NASA Technical Reports Server (NTRS)

    Weber, M.; Tang, S.; Khatri, R.; Berko, S.; Canter, K. F.; Lynn, K. G.; Mills, A. P., Jr.; Roellig, L. O.; Viescas, A. J.

    1990-01-01

    Specular reflection of positronium, Ps was observed and that there is adequate intensity at higher energies to make further study worthwhile was established. The scattering appears to be restricted to the outermost surface with a mean free path of (0.75 + or - 0.15)A for Ps in LiF(100). With a greater intensity Ps beam one should see higher order diffraction beams as the result of the periodicity of the surface. Ps diffraction thus offers the possibility of being a novel and valuable probe to study the outermost surface and to study adsorbants on it. Two methods for producing Ps beams are described.

  2. Positronium reflection and positronium beams

    SciTech Connect

    Weber, M.; Tang, S.; Khatri, R.; Roellig, L.O.; Viescas, A.J. ); Berko, S.; Canter, K.F. ); Lynn, K.G. ); Mills, A.P. Jr. )

    1989-01-01

    We have observed specular reflection of positronium, Ps, and established that there is adequate intensity at higher energies to make further study worthwhile. The scattering appears to be restricted to the outermost surface with a mean free path of (0.75 {plus minus} 0.15){Angstrom} for Ps in LiF(100). With a greater intensity Ps beam one should see higher order diffraction beams as the result of the periodicity of the surface. Ps diffraction thus offers the possibility of being a novel and valuable probe to study the outermost surface and to study adsorbents on it. Two methods for producing Ps beams are described. 29 refs., 11 figs.

  3. Dwelling in Possibilities

    ERIC Educational Resources Information Center

    Edmundson, Mark

    2008-01-01

    Following an encounter with a student at the beginning of fall term, the writer reflects that today's student generation is a singular one: its members want to study, travel, make friends, make more friends, read everything (superfast), take in all the movies, listen to every hot band, keep up with everyone they've ever known. They live to…

  4. Verification of reflectance models in turbid waters

    NASA Technical Reports Server (NTRS)

    Tanis, F. J.; Lyzenga, D. R.

    1981-01-01

    Inherent optical parameters of very turbid waters were used to evaluate existing water reflectance models. Measured upwelling radiance spectra and Monte Carlo simulations of the radiative transfer equations were compared with results from models based upon two flow, quasi-single scattering, augmented isotropic scattering, and power series approximation. Each model was evaluated for three separate components of upwelling radiance: (1) direct sunlight; (2) diffuse skylight; and (3) internally reflected light. Limitations of existing water reflectance models as applied to turbid waters and possible applications to the extraction of water constituent information are discussed.

  5. A note on weak shock wave reflection

    NASA Astrophysics Data System (ADS)

    Viero, D. P.; Susin, F. M.; Defina, A.

    2013-09-01

    This work discusses the possibility of reconstructing, both numerically and experimentally, the steady state flow field and shock reflection pattern close to the triple point of von Neumann, Guderley and Vasilev reflections. First, a criterion for the orientation of shock wave fronts, even in the case of subcritical/subsonic flow downstream the front, is introduced and formalized. Then, a technique for obtaining a close view of the above reflection patterns centered about the triple point is described and a numerical example, within the framework of shallow water flow, is presented and discussed.

  6. Gompertz' survivorship law as an intrinsic principle of aging.

    PubMed

    Sas, Arthur A; Snieder, Harold; Korf, Jakob

    2012-05-01

    We defend the hypothesis that life-spanning population survivorship curves, as described by Gompertz' law and composed from cross-sectional data (here mortality), reflect an intrinsic aging principle active in each subject of that population. In other words Gompertz' law reflects aging of a prototypical subject, provided minimal (or no) external causes of death (i.e. fatal infections, starvation, accidents). Our approach deviates from the traditional (exponential) Gompertz' hazard function. For instance, the here formulated Gompertz' law accurately describes old-age deceleration of both all-cause mortality and the incidence of some ageing-associated cancers, as illustrated for the Dutch population. We consider the possibility that the old-age expression and progression of cancer and other pathologies becomes suppressed, because of random (and exponential) accumulation of damage during life. Gompertz' law may trigger new concepts and models describing life-spanning physiological and pathological processes of aging. We discuss (and reject) various aging models (e.g. a predominant role of individual variations at birth; reliability theory) and point to the explanatory potential of network models and systemic regulatory models.

  7. Weak shock reflection

    NASA Astrophysics Data System (ADS)

    Hunter, John K.; Brio, Moysey

    2000-05-01

    We present numerical solutions of a two-dimensional inviscid Burgers equation which provides an asymptotic description of the Mach reflection of weak shocks. In our numerical solutions, the incident, reflected, and Mach shocks meet at a triple point, and there is a supersonic patch behind the triple point, as proposed by Guderley for steady weak-shock reflection. A theoretical analysis indicates that there is an expansion fan at the triple point, in addition to the three shocks. The supersonic patch is extremely small, and this work is the first time it has been resolved.

  8. Our Visions of Possibility for Literacy

    ERIC Educational Resources Information Center

    O'Keefe, Tim; Reinier, Rise; Gallagher, Kevin; Morgan, Bruce; Lopez-Robertson, Julia; Santman, Donna; Wong-Kam, JoAnn; Hill, Sharon; Christensen, Linda

    2006-01-01

    Tim O'Keefe, Rise Reinier and Kevin Gallagher, Bruce Morgan, Julia Lopez-Robertson, Donna Santman, JoAnn Wong-Kam, Sharon Hill, and Linda Christensen provide short essays describing their personal visions of possibility about literacy and how they maintain that passion and vision. Across a range of contexts, they reflect on the ways in which their…

  9. Envy, politics, and age.

    PubMed

    Harris, Christine R; Henniger, Nicole E

    2013-01-01

    In the last 5 years, the phrase "politics of envy" has appeared more than 621 times in English-language newspapers, generally in opinion essays contending that political liberalism reflects and exploits feelings of envy. Oddly, this assertion has not been tested empirically. We did so with a large adult sample (n = 357). Participants completed a Dispositional Envy Scale and questions about political ideology, socioeconomic status, and age. Envy and age were moderately correlated; younger people reported greater envy. Political ideology and envy were weakly correlated; however, this relationship was not significant when controlling for age. PMID:23471177

  10. Encouraging Counsellor Reflection.

    ERIC Educational Resources Information Center

    Upton, David; Asch, Rachel

    1999-01-01

    Describes the evolution and testing of an "attributes checklist" tool for assisting counselor development. These attributes relate to characteristics of case notes that indicate evidence of counselor reflection and consideration of the counseling process. (Author/GCP)

  11. Seasonal soybean crop reflectance

    NASA Technical Reports Server (NTRS)

    Lemaster, E. W. (Principal Investigator); Chance, J. E.

    1983-01-01

    Data are presented from field measurements of 1980 including 5 acquisitions of handheld radiometer reflectance measurements, 7 complete sets of parameters for implementing the Suits mode, and other biophysical parameters to characterize the soybean canopy. LANDSAT calculations on the simulated Brazilian soybean reflectance are included along with data collected during the summer and fall on 1981 on soybean single leaf optical parameters for three irrigation treatments. Tests of the Suits vegetative canopy reflectance model for the full hemisphere of observer directions as well as the nadir direction show moderate agreement for the visible channels of the MSS and poor agreement in the near infrared channel. Temporal changes in the spectral characteristics of the single leaves were seen to occur as a function of maturity which demonstrates that the absorptance of a soybean single leaf is more a function of thetransmittancee characteristics than the seasonally consistent single leaf reflectance.

  12. Reflectance of aqueous solutions

    NASA Technical Reports Server (NTRS)

    Querry, M. R.

    1972-01-01

    The optical properties and optical constants of water and aqueous solutions were studied to develop an accurate tabulation of graphical representations of the optical constants through a broad spectrum. Manuscripts of articles are presented concerning extinction coefficients, relative specular reflectance, and temperature effect on the water spectrum. Graphs of absolute reflectance, phase shifts, index of refraction, and extinction coefficients for water, heavy water and aqueous solutions are included.

  13. Managing Diversity: Reflections of Tourette Syndrome Sufferers.

    ERIC Educational Resources Information Center

    Wilson, Jeni; Shrimpton, Bradley

    This paper discusses a study that investigated the management of Tourette Syndrome (TS), particularly how self-reflection and instruction affects the frequency of TS behaviors. The study included 3 girls and 24 boys (ages 7-17) with TS from Victoria and New South Wales, Australia. When students were asked to indicate their general self-image and…

  14. The essence of aging

    PubMed Central

    Vijg, Jan; Kennedy, Brian K.

    2015-01-01

    The idea that aging is a purposeful, programmed series of events is intuitively appealing based on its many conserved aspects and the demonstrated feasibility of modifying life span by manipulating single genes or pathways. Yet, the case for a non-adaptive basis of aging is strong and now all but generally accepted in the field. Here, we briefly review why the case for programmed aging is weak, with a focus on the lack of possible evolutionary beneficial effects. PMID:26389968

  15. Analytical elimination of substrate backside reflections from reflectance measurements.

    PubMed

    Wilbrandt, Steffen; Stenzel, Olaf

    2016-09-01

    An analytical approach to eliminate substrate backside reflections from measured reflectance of an unknown optical coating has been deducted. Thereby, measured transmittance, reflectance, and backside reflectance of the coating and transmittance and reflectance of the uncoated substrate at the desired angle of incidence and polarization state are required as input data. In the underlying theory, layer and substrate materials may be absorbing. PMID:27607274

  16. Reflection of a birth reflections midwife.

    PubMed

    Cooper, Meg

    2015-10-01

    Supporting a woman's emotional recovery following what can sometimes be a traumatic event is becoming an important part of postnatal care. That simple question, "How was the birth?" can be the first step in allowing a woman to acknowledge and voice her innermost anxieties around the birth of her baby, and put her on the right path towards feeling better about it, if need be. The birth reflections service has been running in our area for almost six years and its purpose is two fold: firstly it provides women with a safe environment in which to talk about their labour and birth, where they can become better informed about the birth and where they can express themselves freely. Secondly, it provides first hand feedback for the maternity service about the care that's been given, enabling us to change practice for the better.

  17. The solar reflectance of a snow field

    NASA Technical Reports Server (NTRS)

    Choudhury, B. J.; Chang, A. T. C.

    1978-01-01

    The radiative transfer equation was solved using a modified Schuster-Schwartzschild approximation to obtain an expression for the solar reflectance of a snow field. The parameters in the reflectance formula are the single scattering albedo and the fraction of energy scattered in the backward direction. The single scattering albedo is calculated from the crystal size using a geometrical optics formula and the fraction of energy scattered in the backward direction is calculated from the Mie scattering theory. Numerical results for reflectance are obtained for visible and near infrared radiation for different snow conditions. Good agreement was found with the whole spectral range. The calculation also shows the observed effect of aging on the snow reflectance.

  18. Understanding aging in Korea.

    PubMed

    Yoon, G; Eun, K

    1995-12-01

    "This study discusses demographic trends, sociocultural characteristics, and policy choices of aging in [South] Korea.... Although the proportion of the elderly was not so high as to worry about aging before 1990, it is projected that one in eight Koreans will be aged 65 or more in 2020. Because the care for the elderly is mostly expected to be provided by each family, not by the state or Korean society, the role of the family is pivotal in coping with [the] aging problem.... Although adult children currently understand that their aged parents need assistance and support from them, they want to solve the issue of support for the elderly in a way different from the traditional.... This paper examines how the changing attitude toward the old is reflected in family life in terms of living arrangement and physical contacts. This paper also describes and discusses the current situation of various welfare policies on the elderly in Korea."

  19. Healthy Aging

    MedlinePlus

    ... About Us Contact Us Text size | Print | Healthy Aging This information in Spanish ( en español ) A healthy ... Aging email updates. Enter email address Submit Healthy Aging news Accessibility | Privacy policy | Disclaimers | FOIA | Link to ...

  20. Healthy Aging

    MedlinePlus

    ... A Change Contrast print sign up Share Healthy Aging This category offers tips on how to stay ... with Smell Problems with Taste Skin Care and Aging Sleep and Aging Taking Medicines Talking with Your ...

  1. Aging, anti-aging, and hormesis.

    PubMed

    Rattan, Suresh I S

    2004-04-01

    As a result of almost 50 years of efforts in collecting descriptive data, biogerontologists are now able to construct general principles of aging and to explore possibilities of gerontomodulation. Most of the data indicate that aging is characterized by a stochastic accumulation of molecular damage and a progressive failure of maintenance and repair, and the genes involved in homeodynamic pathways are the most likely candidate virtual gerontogenes. Several approaches are being tried and tested to modulate aging in a wide variety of organisms, but with the ultimate aim of improving the quality of human life in old age. These approaches include gene therapy, hormonal supplementation, nutritional modulation, and intervention by antioxidants and other molecules. A recent approach is that of applying hormesis in aging research and therapy, which is based on the principle of stimulation of maintenance and repair pathways by repeated exposure to mild stress.

  2. Radar reflectivity of titan.

    PubMed

    Muhleman, D O; Grossman, A W; Butler, B J; Slade, M A

    1990-05-25

    The present understanding of the atmosphere and surface conditions on Saturn's largest moon, Titan, including the stability of methane, and an application of thermodynamics leads to a strong prediction of liquid hydrocarbons in an ethane-methane mixture on the surface. Such a surface would have nearly unique microwave reflection properties due to the low dielectric constant. Attempts were made to obtain reflections at a wavelength of 3.5 centimeters by means of a 70-meter antenna in California as the transmitter and the Very Large Array in New Mexico as the receiving instrument. Statistically significant echoes were obtained that show Titan is not covered with a deep, global ocean of ethane, as previously thought. The experiment yielded radar cross sections normalized by the Titan disk of 0.38 +/- 0.15, 0.78 +/- 0.15, and 0.25 +/- 0.15 on three consecutive nights during which the sub-Earth longitude on Titan moved 50 degrees. The result for the combined data for the entire experiment is 0.35 +/- 0.08. The cross sections are very high, most consistent with those of the Galilean satellites; no evidence of the putative liquid ethane was seen in the reflection data. A global ocean as shallow as about 200 meters would have exhibited reflectivities smaller by an order of magnitude, and below the detection limit of the experiment. The measured emissivity at similar wavelengths of about 0.9 is somewhat inconsistent with the high reflectivity.

  3. Headache and ADHD in Pediatric Age: Possible Physiopathological Links.

    PubMed

    Paolino, Maria Chiara; Ferretti, Alessandro; Villa, Maria Pia; Parisi, Pasquale

    2015-07-01

    Primary headache and attention-deficit/hyperactivity disorder (ADHD) are common disorders in children and adolescences, frequently associated to severe cognitive, emotional, and behavioral impairments. They both are a disabling condition with consequences on family and child's quality of life. Literature data on their association are contrasting. Dopaminergic system dysfunction, brain iron deficiency, and sleep disturbance should be considered to better understand headache and ADHD overlap. In this review, we analyze the complex association between these two diseases and the potential impact on child neurodevelopment. PMID:26049768

  4. Interference reflection microscopy.

    PubMed

    Barr, Valarie A; Bunnell, Stephen C

    2009-12-01

    Interference reflection microscopy (IRM) is an optical technique used to study cell adhesion or cell mobility on a glass coverslip. The interference of reflected light waves generates images with high contrast and definition. IRM can be used to examine almost any cell that will rest upon a glass surface, although it is most useful in examining sites of close contact between a cell and substratum. This unit presents methods for obtaining IRM images of cells with particular emphasis on IRM imaging with a laser scanning confocal microscope (LSCM), as most LSCM are already capable of recording these images without any modification of the instrument. Techniques are presented for imaging fixed and live cells, as well as simultaneous multi-channel capture of fluorescence and reflection images.

  5. Biology Reflective Assessment Curriculum

    NASA Astrophysics Data System (ADS)

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  6. Making Aging "Real" for Undergraduates.

    ERIC Educational Resources Information Center

    Altpeter, Mary; Marshall, Victor W.

    2003-01-01

    Part of an undergraduate introductory aging course was an experiential web-based exercise on calculating life expectancy, which used transformative learning methods. Data from 12 undergraduates revealed the reflective exercise stimulated thinking and increased awareness of and sensitivity to aging. (Contains 11 references.) (SK)

  7. Design for reflection.

    PubMed

    Bagnara, Sebastiano; Pozzi, Simone

    2012-01-01

    Since a few years, a number of academic papers have been proposing to shift from user-centered design to human-centered (or person) design. In this contribution, we discuss as the common tread underlying these works the idea that design should also address the reflective part of our human experience, and not only aim to maximize the experiential aspects. Our review is complemented with examples derived from the internet world and from ICT consumer products. The main research areas we see as promising for the approach of "design for reflection" are: design for pauses, design for detachment, design for serendipity. PMID:22316867

  8. Reflections on a Changing Educational Environment

    ERIC Educational Resources Information Center

    Awender, Michael

    1978-01-01

    Reflects on some serious educational problems--a lack of time, a lack of promotional possibilities that leads to morale and motivational difficulties, a lack of clear relevant curriculum, and a lack of leadership--faced by teachers. (Author/RK)

  9. Reflections on Learning in Interdisciplinary Settings

    ERIC Educational Resources Information Center

    Andersson, Asa; Kalman, Hildur

    2010-01-01

    In the present article, we will reflect on some didactic challenges and possibilities that emerge when teaching in interdisciplinary settings, and we will use and discuss the journey as a metaphor for learning. We argue that teaching in interdisciplinary studies rests on movements between different understandings, and that it gives ample…

  10. Interactive Reflective Logs

    ERIC Educational Resources Information Center

    Deaton, Cynthia Minchew; Deaton, Benjamin E.; Leland, Katina

    2010-01-01

    The authors created an interactive reflective log (IRL) to provide teachers with an opportunity to use a journal approach to record, evaluate, and communicate student understanding of science concepts. Unlike a traditional journal, the IRL incorporates prompts to encourage students to discuss their understanding of science content and science…

  11. Renew, Reflect, and Refresh

    ERIC Educational Resources Information Center

    Texley, Juliana

    2005-01-01

    Is that the sound of the last bus leaving the schoolyard? Or the staff's collective sigh of relief? School's out. Now it's time to nurture the lifelong learner deep inside with a summer reading list that will allow teachers to renew, reflect, and refresh. The National Science Education Standards reminds us, "Becoming an effective science teacher…

  12. Reflections: Children and Literature.

    ERIC Educational Resources Information Center

    And Others; Cianciolo, Patricia J.

    1980-01-01

    Six educational leaders--Patricia J. Cianciolo, Lee Bennett Hopkins, Nancy Larrick, Alan C. Purves, Morton Schindel, and James R. Squire--offer reflections on signficiant developments in children's literature during the 1970s, their hopes for the 1980s, and references that constitute required reading for elementary language arts teachers. (ET)

  13. Lights, Camera, Reflection!

    ERIC Educational Resources Information Center

    Mourlam, Daniel

    2013-01-01

    There are many ways to critique teaching, but few are more effective than video. Personal reflection through the use of video allows one to see what really happens in the classrooms--good and bad--and provides a visual path forward for improvement, whether it be in one's teaching, work with a particular student, or learning environment. This…

  14. Reflections on 1972

    ERIC Educational Resources Information Center

    Gutierrez, Ramon A.

    2007-01-01

    In this article, the author reflects on the events that took place in the year 1972. The author was a junior at the University of New Mexico back then, refusing to eat or buy grapes and lettuce, picketing grocers who did not carry United Farm Workers of America produce. He and his buddies cast their votes against granting Richard Nixon a second…

  15. Clinical Linguistics: Conversational Reflections

    ERIC Educational Resources Information Center

    Crystal, David

    2013-01-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference…

  16. Reflections, 15 Years Later

    ERIC Educational Resources Information Center

    Knox, George

    2016-01-01

    George Knox reflects on his 15-year career as president of Labette Community College in Parsons, Kansas. Knox writes that, as a first-time president coming into a brand new system, he was very fortunate to have many seasoned presidents and mentors in Kansas and from the American Association of Community Colleges' (AACC) Presidents Academy. He says…

  17. Reflections on "La Esperanza"

    ERIC Educational Resources Information Center

    Cortez, Anita

    2007-01-01

    The author was recently asked to reflect on her "educational journey." As far as she can remember she has been hungry to learn. A friend once described her as having "hambres atrasadas," which he described as a kind of "hunger nipping at her heels." It goes back, of course, to her parents: Her father's and her early journeys scavenging the Wyoming…

  18. Reflecting on Data

    ERIC Educational Resources Information Center

    Kraus, Rudolf V.

    2014-01-01

    This article describes a two-day optics laboratory activity that investigates the scientific phenomenon of reflection, which students are generally familiar with but usually have not studied in depth. This investigation can be used on its own or as part of a larger unit on optics. This lesson encourages students to think critically and…

  19. Reflecting on Writing Autobiography

    ERIC Educational Resources Information Center

    Begg, Andy

    2011-01-01

    The following reflections relate to the reasons for and an approach to an autobiographic task, the notions that underpin it, and some thoughts about the quality and value of such a project. The focus was on the ways one views curriculum change over time; and the intention was to provide an example that others may sense as either familiar or at…

  20. Reflective Database Access Control

    ERIC Educational Resources Information Center

    Olson, Lars E.

    2009-01-01

    "Reflective Database Access Control" (RDBAC) is a model in which a database privilege is expressed as a database query itself, rather than as a static privilege contained in an access control list. RDBAC aids the management of database access controls by improving the expressiveness of policies. However, such policies introduce new interactions…

  1. Reflection by Porro Prisms

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2010-04-01

    Students all know that reflection from a plane mirror produces an image that is reversed right to left and so cannot be read by anyone but Leonardo da Vinci, who kept his notes in mirror writing. A useful counter-example is the Porro prism, which produces an image that is not reversed.

  2. Reflecting through Peshkin's I's

    ERIC Educational Resources Information Center

    Savage, Jonathan

    2007-01-01

    Reflection is an appropriate way of accounting for professional practice and is a standard way in which one can "become better acquainted with one's own story". Defining "subjectivity" as "the quality of an investigator that affects the results of observational investigation", Peshkin highlights the requirement for any observer of, or participant…

  3. First Amendment Reflections.

    ERIC Educational Resources Information Center

    Update on Law-Related Education, 1998

    1998-01-01

    Offers seven reflections on the First Amendment and related issues by attorneys, a professor, project directors, and a university president. Highlights an activity where pairs of students prepare either a pro or con argument for each of the seven excerpts and then participate in a debate. (CMK)

  4. Reflections on "Higher Education"

    ERIC Educational Resources Information Center

    Gilbert, Felix

    1974-01-01

    The elitist, professional, and philosophical elements of higher education are reflected upon with stress on the differences between higher education and higher learning, where education is concerned with giving wider groups a share in a broad image of man, and learning is concerned with increasing specialization. (JH)

  5. Possible markets for dirigibles

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The use of mini, small, medium, and heavy dirigibles for the transportation of passengers and cargo, for aerial handling of materials, for the support of scientific platforms, and for use in agriculture and forest management is evaluated. The operational efficiency of one or more dirigibles in view of possible integration into the general transport system is described.

  6. Income, age and financial satisfaction.

    PubMed

    Hsieh, Chang-ming

    2003-01-01

    Although the effects of income and age on subjective well-being have been widely studied, research on the effects of income and age on financial satisfaction, a major life domain to which income has direct relevance, remains limited. Analyzing data from the General Social Surveys, this article empirically examined the effects of income and age on financial satisfaction. These findings suggest that the social-psychological mechanisms underlying the age differences in the effects of income on financial satisfaction might not reflect a clear-cut status attainment versus status maintenance framework. The findings also served to caution future financial satisfaction research in the choice of income measures and the age grouping.

  7. Doppler-shifted self-reflected wave from a semiconductor

    NASA Astrophysics Data System (ADS)

    Schuelzgen, Alex; Hughes, S.; Peyghambarian, Nasser

    1997-06-01

    We report the first experimental observation of a self- reflected wave inside a very dense saturable absorber. An intense femtosecond pulse saturates the absorption and causes a density front moving into the semiconductor sample. Due to the motion of the boundary between saturated and unsaturated areas of the sample the light reflected at this boundary is red-shifted by the Doppler effect. The spectrally shifted reflection makes it possible to distinguish between surface reflection and self-reflection and is used to proof the concept of the dynamic nonlinear skin effect experimentally. Quite well agreement with model calculations is found.

  8. Dispersion effects on infrared spectra in attenuated total reflection

    NASA Astrophysics Data System (ADS)

    Belali, Rabah; Vigoureux, Jean-Marie; Morvan, Joseph

    1995-12-01

    A potential problem with the attenuated total reflection that is used to measure infrared spectra is described. The problem is the possibility that the anomalous dispersion associated with an infrared absorption band may cause the experimental configuration to move from the attenuated total reflection regime to the specular reflection regime, with consequent distortion of the apparent absorption bands and consequent error in the interpretation of the bands if the problem is not recognized. Key infrared spectra, attenuated total reflection, specular reflection, polyethylene terephtalate. Copyright (c) 1995 Optical Society of America

  9. Engaging Young Students in Scientific Investigations: Prompting for Meaningful Reflection

    ERIC Educational Resources Information Center

    Wilson, Travis; Perry, Michelle; Anderson, Carolyn J.; Grosshandler, Dean

    2012-01-01

    This study examined the verbal prompts a tutor used to promote reflection and young students' responses to these prompts. Seven children (ages 8-12) participated in 260 min of one-on-one tutoring to learn scientific concepts related to gear movement; the tutor spontaneously provided these students with 763 prompts for reflection. Prompts reliably…

  10. Parenting and Adolescent Adjustment: The Role of Parental Reflective Function

    ERIC Educational Resources Information Center

    Benbassat, Naomi; Priel, Beatriz

    2012-01-01

    Reflective function (RF) is the capacity to reflect on one's own mental experiences and those of others. This study examined the relationship between parental RF and adolescent adjustment. One hundred and five adolescents, aged 14-18, and their mothers and fathers were interviewed and completed questionnaires during home visits. We measured…

  11. A Small as Possible

    NASA Technical Reports Server (NTRS)

    Tibbitts, Scott

    2003-01-01

    This story begins with a bit of serendipity: I was on a trip to see a Shuttle launch and I happened to sit next to a guy who was in charge of batteries for Space Systems/Loral. He told me that they needed to create a new battery bypass switch, the device that takes a battery out of commission if it goes bad. After discussing the conversation back at my company, we decided that we could create the switch. We contacted the folks at Loral and they said, 'Okay, let s see what you can come up with. We need it as small as possible.' We asked, 'How small?' They said, 'We need it as small as you can possibly make it.'

  12. Normal-reflection image

    SciTech Connect

    Huang, L.; Fehler, Michael C.

    2003-01-01

    Common-angle wave-equation migration using the double-square-root is generally less accurate than the common-shot migration because the wavefield continuation equation for thc former involves additional approximations compared to that for the latter. We present a common-angle wave-equation migration that has the same accuracy as common-shot wave-equation migration. An image obtained from common-angle migration is a four- to five-dimensional output volume for 3D cases. We propose a normal-reflection imaging condition for common-angle migration to produce a 3D output volume for 3D migration. The image is closely related to the normal-reflection coefficients at interfaces. This imaging condition will allow amplitude-preserving migration to generate an image with clear physical meaning.

  13. Trifid reflection nebulae

    SciTech Connect

    Lynds, B.T.; Oneil, E.J. Jr.

    1986-11-01

    CCD frames of reflected starlight in the blue continuum, 4693 A, associated with the Trifid emission nebulae have been used to deduce the optical depth, albedo, and phase function of the dust grains. The northern component of the Trifid, centered on the supergiant HD 164514, apparently has grains of higher albedo than those associated with the southern O star HD 164492A. IRAS data add further arguments to the assumption that the northern reflection nebula is illuminated by the supergiant, and that the dust grains surrounding the O star have a higher grain temperature. The entire complex is probably part of the Sgr OB I association and the short lifetime of the association puts constraints on the manner in which the properties of the grains can be modified by associated young stars. 26 references.

  14. The Trifid reflection nebulae

    NASA Astrophysics Data System (ADS)

    Lynds, Beverly T.; Oneil, Earl J., Jr.

    1986-11-01

    CCD frames of reflected starlight in the blue continuum, λ 4693, associated with the Trifid emission nebulae have been used to deduce the optical depth, albedo, and phase function of the dust grains. The northern component of the Trifid, centered on the supergiant HD 164514, apparently has grains of higher albedo than those associated with the southern O star HD 164492A. IRAS data add further arguments to the assumption that the northern reflection nebula is illuminated by the supergiant and that the dust grains surrounding the O star have a higher grain temperature. The entire complex is probably part of the Sgr OB I association and the short lifetime of the association puts constraints on the manner in which the properties of the grains can be modified by associated young stars.

  15. Clinical linguistics: conversational reflections.

    PubMed

    Crystal, David

    2013-04-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference participants during that time.

  16. Landsat surface reflectance data

    USGS Publications Warehouse

    ,

    2015-01-01

    Landsat satellite data have been produced, archived, and distributed by the U.S. Geological Survey since 1972. Users rely on these data for historical study of land surface change and require consistent radiometric data processed to the highest science standards. In support of the guidelines established through the Global Climate Observing System, the U.S. Geological Survey has embarked on production of higher-level Landsat data products to support land surface change studies. One such product is Landsat surface reflectance.

  17. Shape and Reflectance Estimation in the Wild.

    PubMed

    Oxholm, Geoffrey; Nishino, Ko

    2016-02-01

    Our world is full of objects with complex reflectances situated in rich illumination environments. Though stunning, the diversity of appearance that arises from this complexity is also daunting. For this reason, past work on geometry recovery has tried to frame the problem into simplistic models of reflectance (such as Lambertian, mirrored, or dichromatic) or illumination (one or more distant point light sources). In this work, we directly tackle the problem of joint reflectance and geometry estimation under known but uncontrolled natural illumination by fully exploiting the surface orientation cues that become embedded in the appearance of the object. Intuitively, salient scene features (such as the sun or stained glass windows) act analogously to the point light sources of traditional geometry estimation frameworks by strongly constraining the possible orientations of the surface patches reflecting them. By jointly estimating the reflectance of the object, which modulates the illumination, the appearance of a surface patch can be used to derive a nonparametric distribution of its possible orientations. If only a single image exists, these strongly constrained surface patches may then be used to anchor the geometry estimation and give context to the less-descriptive regions. When multiple images exist, the distribution of possible surface orientations becomes tighter as additional context is given, though integrating the separate views poses additional challenges. In this paper we introduce two methods, one for the single image case, and another for the case of multiple images. The effectiveness of our methods is evaluated extensively on synthetic and real-world data sets that span the wide range of real-world environments and reflectances that lies between the extremes that have been the focus of past work. PMID:26761741

  18. Troubling Muddy Waters: Problematizing Reflective Practice in Global Medical Education.

    PubMed

    Naidu, Thirusha; Kumagai, Arno K

    2016-03-01

    The idea of exporting the concept of reflective practice for a global medical education audience is growing. However, the uncritical export and adoption of Western concepts of reflection may be inappropriate in non-Western societies. The emphasis in Western medical education on the use of reflection for a specific end--that is, the improvement of individual clinical practice--tends to ignore the range of reflective practice, concentrating on reflection alone while overlooking critical reflection and reflexivity. This Perspective places the concept of reflective practice under a critical lens to explore a broader view for its application in medical education outside the West. The authors suggest that ideas about reflection in medicine and medical education may not be as easily transferable from Western to non-Western contexts as concepts from biomedical science are. The authors pose the question, When "exporting" Western medical education strategies and principles, how often do Western-trained educators authentically open up to the possibility that there are alternative ways of seeing and knowing that may be valuable in educating Western physicians? One answer lies in the assertion that educators should aspire to turn exportation of educational theory into a truly bidirectional, collaborative exchange in which culturally conscious views of reflective practice contribute to humanistic, equitable patient care. This discussion engages in troubling the already-muddy waters of reflective practice by exploring the global applicability of reflective practice as it is currently applied in medical education. The globalization of medical education demands critical reflection on reflection itself.

  19. Skin Aging

    MedlinePlus

    ... too. Sunlight is a major cause of skin aging. You can protect yourself by staying out of ... person has smoked. Many products claim to revitalize aging skin or reduce wrinkles, but the Food and ...

  20. Reflections on 25 Years of Journal Editorship

    NASA Astrophysics Data System (ADS)

    Matthews, Michael R.

    2015-07-01

    These reflections range over some distinctive features of the journal Science & Education, they acknowledge in a limited way the many individuals who over the past 25 years have contributed to the success and reputation of the journal, they chart the beginnings of the journal, and they dwell on a few central concerns—clear writing and the contribution of HPS to teacher education. The reflections also revisit the much-debated and written-upon philosophical and pedagogical arguments occasioned by the rise and possible demise of constructivism in science education.

  1. Quantitative Analyses of Planetary Reflectance Spectra

    NASA Technical Reports Server (NTRS)

    Johnson, P. E.

    1985-01-01

    The development of a set of quantitative models to analyze planetary reflectance spectra as a function of microscopic and macroscopic mineral mixtures, particle size, and illumination geometry is considered. The approach has been to simplify more sophisticated algorithms to include the smallest number of parameters possible, consistent with being able to use them to produce useful results. This means that they should be able to model the data to within the accuracy obtainable by laboratory, telescopic, and space instrumentation (roughly 1%). The algorithms are ideally given in terms of parameters that are directly measureable (such as spectral reflectance or particle size).

  2. Teaching Reflection Seismic Processing

    NASA Astrophysics Data System (ADS)

    Forel, D.; Benz, T.; Pennington, W. D.

    2004-12-01

    Without pictures, it is difficult to give students a feeling for wave propagation, transmission, and reflection. Even with pictures, wave propagation is still static to many. However, when students use and modify scripts that generate wavefronts and rays through a geologic model that they have modified themselves, we find that students gain a real feeling for wave propagation. To facilitate teaching 2-D seismic reflection data processing (from acquisition through migration) to our undergraduate and graduate Reflection Seismology students, we use Seismic Un*x (SU) software. SU is maintained and distributed by Colorado School of Mines, and it is freely available (at www.cwp.mines.edu/cwpcodes). Our approach includes use of synthetic and real seismic data, processing scripts, and detailed explanation of the scripts. Our real data were provided by Gregory F. Moore of the University of Hawaii. This approach can be used by any school at virtually no expense for either software or data, and can provide students with a sound introduction to techniques used in processing of reflection seismic data. The same software can be used for other purposes, such as research, with no additional expense. Students who have completed a course using SU are well equipped to begin using it for research, as well. Scripts for each processing step are supplied and explained to the students. Our detailed description of the scripts means students do not have to know anything about SU to start. Experience with the Unix operating system is preferable but not necessary -- our notes include Computer Hints to help the beginner work with the Unix operating system. We include several examples of synthetic model building, acquiring shot gathers through synthetic models, sorting shot gathers to CMP gathers, gain, 1-D frequency filtering, f-k filtering, deconvolution, semblance displays and velocity analysis, flattening data (NMO), stacking the CMPs, and migration. We use two real (marine) data sets. One

  3. Software for a GPS-Reflection Remote-Sensing System

    NASA Technical Reports Server (NTRS)

    Lowe, Stephen

    2003-01-01

    A special-purpose software Global Positioning System (GPS) receiver designed for remote sensing with reflected GPS signals is described in Delay/Doppler-Mapping GPS-Reflection Remote-Sensing System (NPO-30385), which appears elsewhere in this issue of NASA Tech Briefs. The input accepted by this program comprises raw (open-loop) digitized GPS signals sampled at a rate of about 20 MHz. The program processes the data samples to perform the following functions: detection of signals; tracking of phases and delays; mapping of delay, Doppler, and delay/Doppler waveforms; dual-frequency processing; coherent integrations as short as 125 s; decoding of navigation messages; and precise time tagging of observable quantities. The software can perform these functions on all detectable satellite signals without dead time. Open-loop data collected over water, land, or ice and processed by this software can be further processed to extract geophysical information. Possible examples include mean sea height, wind speed and direction, and significant wave height (for observations over the ocean); bistatic-radar terrain images and measures of soil moisture and biomass (for observations over land); and estimates of ice age, thickness, and surface density (for observations over ice).

  4. Characterizing mechanical effects of aging damage

    SciTech Connect

    Sewell, T.D.; Chen, S.P.; Schoonover, J.R.; Trent, B.C.; Howe, P.M.; Hjelm, R.P.; Browning, R.V.

    1998-12-01

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal was to develop and apply several different experimental and theoretical/computational tools to better understand physical and chemical aging phenomena in plastic-bonded high explosives, and to develop a methodology for predicting the likely effects of aging on the mechanical properties of the composite based on input from these fundamental studies. Initial comparisons were done for spectra of fresh and aged Esane, as well as PBX-9501, and the authors found differences in the carbonyl region of the spectrum, which possibly reflect differences in hydrogen bonding due to aging phenomena. The micromechanical model of composites was extended to study various volume fractions of HMX with binders. The results showed that, as the binder fraction increases, there is a decrease in the maximum stress that can be supported but an increase in the percent strain at final fracture. A more realistic microstructural model was obtained through the use of a phase field model. Using this model, the authors have studied the microstructural evolution as a function of the grain boundary energy vs. misorientation relationship. The initial results indicate that there are some changes in the grain growth rate when the grain-boundary energy dependence on the angle is not constant. They also find that solute tends to segregate at the grain boundary and slows the grain growth kinetics.

  5. Possibilities of Engineering Ethics Education

    NASA Astrophysics Data System (ADS)

    Matsuki, Junya

    This paper discusses the possibilities of teaching engineering ethics in universities. This is based on the teaching experience of a newly developed course that has been introduced to the Department of Electrical and Electronic Engineering at the University of Fukui, since April 2004. Entitled “ethics for engineers”, the course targeted senior-level students and makes use of a newly written textbook that emphasizes social aspects of science and technology. To encourage students to think and form their own opinions with regards to their role as engineers in a modern technological society, the book is complemented by other materials such as videos, newspaper articles and some other relevant books. Students are also encouraged to write reports that reflect their own opinion on subjects such as what kind of engineers they intend to be, or what do ethics mean to them? The paper will conclude by giving a course evaluation including students' response, highlighting valuable experiences and stating the importance of further developing this topic in engineering education.

  6. Seismic reflection imaging, accounting for primary and multiple reflections

    NASA Astrophysics Data System (ADS)

    Wapenaar, Kees; van der Neut, Joost; Thorbecke, Jan; Broggini, Filippo; Slob, Evert; Snieder, Roel

    2015-04-01

    Imaging of seismic reflection data is usually based on the assumption that the seismic response consists of primary reflections only. Multiple reflections, i.e. waves that have reflected more than once, are treated as primaries and are imaged at wrong positions. There are two classes of multiple reflections, which we will call surface-related multiples and internal multiples. Surface-related multiples are those multiples that contain at least one reflection at the earth's surface, whereas internal multiples consist of waves that have reflected only at subsurface interfaces. Surface-related multiples are the strongest, but also relatively easy to deal with because the reflecting boundary (the earth's surface) is known. Internal multiples constitute a much more difficult problem for seismic imaging, because the positions and properties of the reflecting interfaces are not known. We are developing reflection imaging methodology which deals with internal multiples. Starting with the Marchenko equation for 1D inverse scattering problems, we derived 3D Marchenko-type equations, which relate reflection data at the surface to Green's functions between virtual sources anywhere in the subsurface and receivers at the surface. Based on these equations, we derived an iterative scheme by which these Green's functions can be retrieved from the reflection data at the surface. This iterative scheme requires an estimate of the direct wave of the Green's functions in a background medium. Note that this is precisely the same information that is also required by standard reflection imaging schemes. However, unlike in standard imaging, our iterative Marchenko scheme retrieves the multiple reflections of the Green's functions from the reflection data at the surface. For this, no knowledge of the positions and properties of the reflecting interfaces is required. Once the full Green's functions are retrieved, reflection imaging can be carried out by which the primaries and multiples are

  7. Study on Reflection as a Source of Teacher Development: Pre-Service and Experienced Teachers

    ERIC Educational Resources Information Center

    Yaman, Saziye

    2016-01-01

    This study traces evidence of reflection in teacher education and teaching practice by measuring reflection of preservice teachers and experienced teachers and clarifying reflection-oriented reactions to possible confusions or problematic situations considering whether or not they are reflective practitioners. The data were collected from 514…

  8. Bragg Reflection of Ocean Waves from Sandbars

    NASA Astrophysics Data System (ADS)

    Elgar, S.; Raubenheimer, B.; Herbers, T. H.

    2002-12-01

    Resonant Bragg reflection of surface waves from a field of roughly shore-parallel sandbars was observed in Cape Cod Bay near Truro, MA during low energy wave conditions and during a storm. Although the Bragg resonance mechanism for wave reflection has been demonstrated convincingly in the laboratory, the corresponding impact of natural sandbars on ocean waves is not known. Multiple shore-parallel sandbars frequently are found in bays and gulfs, but observations of associated wave reflection have not been reported. Here, we present the first observations of resonant Bragg reflection of ocean surface waves by a natural field of sandbars. The waves were reflected both from the bars and from the steep beach shoreward of the bars, causing complicated interference patterns of seaward and shoreward propagating waves. The observed cross-shore variations in the onshore- and offshore-directed energy fluxes are consistent with theory (Yu and Mei JFM 2000) for resonant Bragg reflection, including a 20% decay of the incident wave energy flux that is an order of magnitude greater than expected for wave-orbital velocity induced bottom friction. When offshore wave heights were small (less than 0.25 m) there was no wave breaking across the sandbars, and the near-bottom velocities associated with the Bragg reflecting waves likely were too small to cause significant sediment transport. However, sediment mobilized during storms may be transported by velocity convergences and divergences associated with nodes and antinodes of the reflecting Bragg waves, possibly resulting in growth of the sandbars. Funding was provided by the Mellon Foundation, ONR, and NSF.

  9. Binary phase digital reflection holograms - Fabrication and potential applications

    NASA Technical Reports Server (NTRS)

    Gallagher, N. C., Jr.; Angus, J. C.; Coffield, F. E.; Edwards, R. V.; Mann, J. A., Jr.

    1977-01-01

    A novel technique for the fabrication of binary-phase computer-generated reflection holograms is described. By use of integrated circuit technology, the holographic pattern is etched into a silicon wafer and then aluminum coated to make a reflection hologram. Because these holograms reflect virtually all the incident radiation, they may find application in machining with high-power lasers. A number of possible modifications of the hologram fabrication procedure are discussed.

  10. Propagator for finite range potentials: The case of reflection

    SciTech Connect

    Cacciari, Ilaria; Moretti, Paolo

    2007-04-15

    Following a previous study on the transmission propagator for a finite range potential, the problem of reflection is considered. It is found that the Laplace transform of the reflection propagator can be expressed in terms of the usual Fredholm determinant {delta} and of a new similar determinant {gamma}, containing the peculiar characteristics of reflection. As an example, an array of delta potentials is considered. Moreover, a possible application to the calculation of quantum traversal time is shown.

  11. Seasonal variation in the structure of red reflectance of leaves from yellow poplar, red oak, and red maple

    NASA Technical Reports Server (NTRS)

    Brakke, Thomas W.; Wergin, William P.; Erbe, Eric F.; Harnden, Joann M.

    1993-01-01

    The light scattered from leaves was measured as a function of view angle in the principal plane for yellow poplar, red oak, and red maple. The source was a parallel-polarized helium-neon laser. Yellow poplar leaves had the highest reflectance of the three species, which may have been due to its shorter palisade cells and more extensive spongy mesophyll. Prior to senescence, there was a significant decrease, but not total extinction, in the reflectance of the beam incident at 60 deg from nadir on the adaxial side of the leaves of all three species. Low-temperature SEM observations showed differences in the surface wax patterns among the three species but did not indicate a cause of the reflectance changes other than possibly the accumulation and aging of the wax.

  12. Hyperparathyroidism and psychosis: possible prelude to murder.

    PubMed

    Bresler, S A; Logan, W S; Washington, D

    2000-05-01

    The authors present a case of a middle aged attorney who suffered from hyperparathyroidism and a psychotic disorder. It is possible that the hyperparathyroidism may have precipitated an acute psychotic delusional rage leading to an attempted mass murder. They discuss the relationship between hyperparathyroidism and neuropsychiatric symptoms in consideration of available research.

  13. Education: A Possibility for Empowering Older Adults

    ERIC Educational Resources Information Center

    Kump, Sonja; Krasovec, Sabina Jelenc

    2007-01-01

    Educating older adults (in the so-called third age) is becoming an increasingly important activity for the elderly, above all because it empowers them, while at the same time reducing their social exclusion. The aim of this paper is to closely examine the actual state of affairs and the education possibilities for older adults in Slovenia. The…

  14. Learning to integrate versus inhibiting information is modulated by age.

    PubMed

    Cappelletti, Marinella; Pikkat, Helen; Upstill, Emily; Speekenbrink, Maarten; Walsh, Vincent

    2015-02-01

    Cognitive training aiming at improving learning is often successful, but what exactly underlies the observed improvements and how these differ across the age spectrum are currently unknown. Here we asked whether learning in young and older people may reflect enhanced ability to integrate information required to perform a cognitive task or whether it may instead reflect the ability to inhibit task-irrelevant information for successful task performance. We trained 30 young and 30 aging human participants on a numerosity discrimination task known to engage the parietal cortex and in which cue-integration and inhibitory abilities can be distinguished. We coupled training with parietal, motor, or sham transcranial random noise stimulation, known for modulating neural activity. Numerosity discrimination improved after training and was maintained long term, especially in the training + parietal stimulation group, regardless of age. Despite the quantitatively similar improvement in the two age groups, the content of learning differed remarkably: aging participants improved more in inhibitory abilities, whereas younger subjects improved in cue-integration abilities. Moreover, differences in the content of learning were reflected in different transfer effects to untrained but related abilities: in the younger group, improvements in cue integration paralleled improvements in continuous quantity (time and space), whereas in the elderly group, improvements in numerosity-based inhibitory abilities generalized to other measures of inhibition and corresponded to a decline in space discrimination, possibly because conflicting learning resources are used in numerosity and continuous quantity processing. These results indicate that training can enhance different, age-dependent cognitive processes and highlight the importance of identifying the exact processes underlying learning for effective training programs.

  15. Is homeopathy possible?

    PubMed

    Milgrom, Lionel R

    2006-09-01

    As a therapeutic intervention, homeopathy is the target of increased scepticism because in the main, its remedies are diluted and succussed (potentized) out of material existence. This puts homeopathy seemingly at odds with the paradigm of conventional science, in particular, that atoms and molecules are the fundamental building blocks of all matter. Accordingly, homeopathy cannot work, so that any reported beneficial effects must, at best, be due to the placebo effect. The purpose of this article is to challenge that conclusion and to suggest that there may well be conventional science-based explanations of how homeopathy could be possible. Homeopathy's key principles are first described. Then the double-blind randomized controlled trial (RCT), the chief means by which homeopathic remedies and prescribing are tested, is shown to be based on a linear reductionism that is too blunt an instrument with which to test the efficacy of complex interventions such as homeopathy The memory of water hypothesis, as a mechanism for how potentized remedies might work, is reviewed, along with some evidence for its existence. A possible rationale for the water memory effect is proposed in terms of a dynamic 'ordering' of water's constantly switching network of intermolecular hydrogen bonds, induced by the manufacturing process of homeopathic remedies. This could lead to a long-range molecular 'coherence' between trillions of mobile water molecules. However, the water memory effect is an essentially pharmacological explanation of homeopathy's putative efficacy. It is pointed out that healing also entails an interaction between consenting beings. From this point of view, an explanation of any therapeutic procedure should include an attempt to describe the nature of the patient-practitioner interaction. From this perspective, a quantum theoretical treatment of the therapeutic process, involving a form of macro-entanglement between patient, practitioner and remedy (PPR), is advanced

  16. Reflections on Rodent Implantation.

    PubMed

    Cha, Jeeyeon M; Dey, Sudhansu K

    2015-01-01

    Embryo implantation is a complex process involving endocrine, paracrine, autocrine, and juxtacrine modulators that span cell-cell and cell-matrix interactions. The quality of implantation is predictive for pregnancy success. Earlier observational studies formed the basis for genetic and molecular approaches that ensued with emerging technological advances. However, the precise sequence and details of the molecular interactions involved have yet to be defined. This review reflects briefly on aspects of our current understanding of rodent implantation as a tribute to Roger Short's lifelong contributions to the field of reproductive physiology. PMID:26450495

  17. Promoting Critical Reflection in Teacher Education through Popular Media

    ERIC Educational Resources Information Center

    Ryan, Patrick A.; Townsend, Jane S.

    2012-01-01

    Recognizing the possible influences of media narratives upon self-concepts, teacher educators have used films and television programs about teachers to promote preservice teachers' reflections on their professional identities and instructional practices. Theoretical models of reflection, in conjunction with media analysis, have the potential to…

  18. Progress Toward Roll Processing of Solar Reflective Material (Presentation)

    SciTech Connect

    Smilgys, R.; Wallace, S.; Kennedy, C.

    2001-04-01

    This presentation discusses the goal of this project which was to demonstrate that it is possible to cost-effectively produce high performance solar reflective material using vacuum deposition techniques.

  19. Reflections on Wilderness Therapy.

    ERIC Educational Resources Information Center

    Eggleston, Erin J.

    Te Whakapakari Youth Programme on Great Barrier Island, New Zealand, is a Maori initiative initially designed to help young Maori, particularly those involved in drug abuse. The program now accepts adjudicated youth, aged 13-18, from many cultures who experience drug, physical, or sexual abuse and exhibit antisocial or violent tendencies. The…

  20. Possibility of hyperbolic tunneling

    SciTech Connect

    Lobo, Francisco S. N.; Mimoso, Jose P.

    2010-08-15

    Traversable wormholes are primarily useful as 'gedanken experiments' and as a theoretician's probe of the foundations of general relativity. In this work, we analyze the possibility of having tunnels in a hyperbolic spacetime. We obtain exact solutions of static and pseudo-spherically symmetric spacetime tunnels by adding exotic matter to a vacuum solution referred to as a degenerate solution of class A. The physical properties and characteristics of these intriguing solutions are explored, and through the mathematics of embedding it is shown that particular constraints are placed on the shape function, that differ significantly from the Morris-Thorne wormhole. In particular, it is shown that the energy density is always negative, and the radial pressure is positive, at the throat, contrary to the Morris-Thorne counterpart. Specific solutions are also presented by considering several equations of state, and by imposing restricted choices for the shape function or the redshift function.

  1. Nebulizer possibilities and limitations.

    PubMed

    Matthys, H

    1991-01-01

    The ban of chlorofluorocarbon (CFC) propellants in metered dose inhalers (MDIs) gives rise to many alternatives and innovations: 1. CFC substitution by non-CFC propellants in MDIs. 2. battery driven miniaturized mechanical and piezoelectric nebulizers 3. revitalization of hand driven pocket nebulizers 4. self actuated dry powder inhalers (DPI's). All devices can be used with or without spacers. The choice for solid or liquid particles, e.g. powder or droplet aerosols, will also depend on the drug properties and the availability on the market for aerosol use. The nebulizer device will be chosen according to the medical need (emergency or long term treatment), the technical alternatives available in different countries, the possibility of patient cooperation (children, severely ill patients), and last not least marketing strategies and costs. The bronchial circulation is an important distribution system for medicine deposited by aerosol routes in the lung.

  2. Honesty in critically reflective essays: an analysis of student practice.

    PubMed

    Maloney, Stephen; Tai, Joanna Hong-Meng; Lo, Kristin; Molloy, Elizabeth; Ilic, Dragan

    2013-10-01

    In health professional education, reflective practice is seen as a potential means for self-improvement from everyday clinical encounters. This study aims to examine the level of student honesty in critical reflection, and barriers and facilitators for students engaging in honest reflection. Third year physiotherapy students, completing summative reflective essays on clinical encounters using the modified Gibbs cycle, were invited to participate in an anonymous online survey. Student knowledge and beliefs about reflective practice, and disclosure of the truthfulness of their reflections, were assessed using a mixed method approach. A total of 34 students, from a maximum possible of 48 (71 %), participated in the study activities. A total of 68 % stated that they were at least 80 % truthful about their experiences. There was general student consensus that reflective practice was important for their growth as a clinician. Students questioned the belief that the reflection needed to be based on a factual experience. Reflective practice can be a valuable addition to the clinical education of health care professionals, although this value can be diminished through dishonest reflections if it is not carefully implemented. Student influences on honest reflection include; (1) the design of any assessment criteria, and (2) student knowledge and competency in applying critical reflection.

  3. The albedo of particles in reflection nebulae

    NASA Technical Reports Server (NTRS)

    Rush, W. F.

    1974-01-01

    The relation between the apparent angular extent of a reflection nebula and the apparent magnitude of its illuminating star was reconsidered under a less restrictive set of assumptions. A computational technique was developed which permits the use of fits to the observed m-log a values to determine the albedo of particles composing reflection nebulae, providing only that a phase function and average optical thickness are assumed. Multiple scattering, anisotropic phase functions, and illumination by the general star field are considered, and the albedo of reflection nebular particles appears to be the same as that for interstellar particles in general. The possibility of continuous fluorescence contributions to the surface brightness is also considered.

  4. Soft tissue differentiation by diffuse reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Zam, Azhar; Stelzle, Florian; Nkenke, Emeka; Tangermann-Gerk, Katja; Schmidt, Michael; Adler, Werner; Douplik, Alexandre

    2009-07-01

    Laser surgery gives the possibility to work remotely which leads to high precision, little trauma and high level sterility. However these advantages are coming with the lack of haptic feedback during the laser ablation of tissue. Therefore additional means are required to control tissue-specific ablation during laser surgery supporting the surgeon regardless of experience and skills. Diffuse Reflectance Spectroscopy provides a straightforward and simple approach for optical tissue differentiation. We measured diffuse reflectance from four various tissue types ex vivo. We applied Linear Discriminant Analysis (LDA) to differentiate the four tissue types and computed the area under the ROC curve (AUC). Special emphasis was taken on the identification of nerve as the most crucial tissue for maxillofacial surgery. The results show a promise for differentiating soft tissues as guidance for tissue-specific laser surgery by means of the diffuse reflectance.

  5. Turkish students' self concepts and reflected appraisals of significant others.

    PubMed

    Hortaçsu, N

    1989-01-01

    It was argued that self concept, being a social construct, should be investigated with instruments developed within the culture studied. A measure based on self descriptions of Turkish students was used to investigate self concepts of Turkish adolescents. Two subsamples of subjects reported on parents' and friends/strangers' reflected appraisals respectively in addition to ideal self concepts. Regression analyses performed on data from male and female subsamples reporting on parents reflected appraisals revealed that mothers reflected appraisals were significant predictors for both sexes, whereas fathers' reflected appraisals and ideal self concepdts were significant for females and males respectively. Regression analyses performed on the second subsample demonstrated that friends' and strangers' reflected appraisals were significant for both males and females. Ideal self concept was a significant predictor for males but not for females. Analyses of variance (Sex × Age × SES) revealed that females reported more positive self concepts than males. Significant effects of Age and SES also emerged. PMID:23336787

  6. Reflected Deck Plan, Reflected Roof Plan, Deck Plan Bridgeport ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Reflected Deck Plan, Reflected Roof Plan, Deck Plan - Bridgeport Covered Bridge, Spanning South Fork of Yuba River at bypassed section of Pleasant Valley Road (originally Virginia Turnpike) in South Yuba River State Park , Bridgeport, Nevada County, CA

  7. Longitudinal Section AA; Reflected Deck Plan; Reflected Ceiling Plan ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Longitudinal Section A-A; Reflected Deck Plan; Reflected Ceiling Plan - Shoreham Railroad Bridge, Former Addison County Railroad (later, Rutland Railroad, Addison Branch), spanning Lemon Fair River above Richville Pond, west of East Shoreham Road, Shoreham, Addison County, VT

  8. Teaching Reflective Care in Japanese Early Childhood Settings

    ERIC Educational Resources Information Center

    Hellman, Anette

    2016-01-01

    The purpose of this article is to explore the way preschool teachers teach reflective care in Japan. The article builds on a two-month ethnographic study conducted in Japanese kindergartens and nurseries among children aged 3-6 years. The data were analysed using concepts of age and gender. The results show that care in Japan, in contrast to…

  9. Aging: overview.

    PubMed

    Harman, D

    2001-04-01

    Aging is a universal process that began with the origination of life about 3.5 billion years ago. Accumulation of the diverse deleterious changes produced by aging throughout the cells and tissues progressively impairs function and can eventually cause death. Aging changes can be attributed to development, genetic defects, the environment, disease, and an inborn process--the aging process. The chance of death at a given age serves as a measure of the average number of aging changes accumulated by persons of that age, that is, of physiologic age, and the rate of change of this measure as the rate of aging. Chances for death are decreased by improvements in general living conditions. As a result, during the past two millennia average life expectancy at birth (ALE-B), determined by the chances for death, of humans has risen from 30 years, in ancient Rome, to almost 80 years today in the developed countries. Chances for death in the developed countries are now near limiting values and ALE-Bs are approaching plateau values that are 6-9 years less than the potential maximum of about 85 years. Chances for death are now largely determined by the inherent aging process after age 28. Only 1.1% of female cohorts in Sweden die before this age; the remainder die off at an exponentially increasing rate with advancing age. The inherent aging process limits ALE-B to around 85 years, and the maximum life span (MLS) to about 122 years. Past efforts to increase ALE-B did not require an understanding of aging. Such knowledge will be necessary in the future to significantly increase ALE-B and MLS, and to satisfactorily ameliorate the medical, economic, and social problems associated with advancing age. The many theories advanced to account for aging should be used, to the extent it is feasible, to help with these important practical problems, including applications of the free radical theory of aging. Past measures evolved by societies to ensure adequate care for older individuals are

  10. Learning about reflection.

    PubMed

    Smith, A

    1998-10-01

    An understanding of the nature and function of reflection in recognizing and developing nursing knowledge is a key concern. This paper describes a longitudinal study investigating the ways in which undergraduate student nurses reflected about practice as they progressed through a 3-year programme in adult nursing. The method was qualitative, with data gained from written critical incidents based on practice experiences and classroom discussions, and analysed using the constant comparative method. Findings revealed the range of issues students perceived as most important, and to some extent, changes in levels of thinking. A strong theme occurring throughout related to the complexity of learning what it means to be a professional and, in consequence, what they learn about themselves. Students' preoccupation with emotional aspects of learning and nursing care was evident. They had difficulty in disentangling 'personal' and 'professional' involvement but later data indicates that they had begun to learn to differentiate between involvement as a general characteristic of nursing practice and a overwhelming personal attachment. They generally use their own and each others' experiences to examine meaning, in preference to formal theoretical explanations although there is evidence students moved from acceptance of information to the questioning and critiquing of arguments and professional assumptions, particularly concerning their relevance and appropriateness for practice.

  11. Quantitative Hyperspectral Reflectance Imaging

    PubMed Central

    Klein, Marvin E.; Aalderink, Bernard J.; Padoan, Roberto; de Bruin, Gerrit; Steemers, Ted A.G.

    2008-01-01

    Hyperspectral imaging is a non-destructive optical analysis technique that can for instance be used to obtain information from cultural heritage objects unavailable with conventional colour or multi-spectral photography. This technique can be used to distinguish and recognize materials, to enhance the visibility of faint or obscured features, to detect signs of degradation and study the effect of environmental conditions on the object. We describe the basic concept, working principles, construction and performance of a laboratory instrument specifically developed for the analysis of historical documents. The instrument measures calibrated spectral reflectance images at 70 wavelengths ranging from 365 to 1100 nm (near-ultraviolet, visible and near-infrared). By using a wavelength tunable narrow-bandwidth light-source, the light energy used to illuminate the measured object is minimal, so that any light-induced degradation can be excluded. Basic analysis of the hyperspectral data includes a qualitative comparison of the spectral images and the extraction of quantitative data such as mean spectral reflectance curves and statistical information from user-defined regions-of-interest. More sophisticated mathematical feature extraction and classification techniques can be used to map areas on the document, where different types of ink had been applied or where one ink shows various degrees of degradation. The developed quantitative hyperspectral imager is currently in use by the Nationaal Archief (National Archives of The Netherlands) to study degradation effects of artificial samples and original documents, exposed in their permanent exhibition area or stored in their deposit rooms.

  12. Reflection: Journals and Reflective Questions: A Strategy for Professional Learning

    ERIC Educational Resources Information Center

    Clarke, Maggie

    2004-01-01

    Reflective journals have been used widely in teacher education programs to promote reflective thinking (Freidus, 1998; Carter & Francis, 2000; Yost, Senter & Forlenzo-Bailey, 2000). Smyth (1992) advocated that posing a series of questions to be answered in written journals could enhance reflective thinking. It was for this reason that…

  13. Reflecting on Reflective Practice: (Re)Visiting Dewey and Schon

    ERIC Educational Resources Information Center

    Farrell, Thomas S. C.

    2012-01-01

    Since the author began work in reflective practice, at first informally in the late 1970s and then more formally in the mid-1980s, he has always looked at reflective practice as a compass of sorts to guide teachers when they may be seeking direction as to what they are doing in their classrooms. The metaphor of reflection as a compass enables…

  14. Robust reflective pupil slicing technology

    NASA Astrophysics Data System (ADS)

    Meade, Jeffrey T.; Behr, Bradford B.; Cenko, Andrew T.; Hajian, Arsen R.

    2014-07-01

    Tornado Spectral Systems (TSS) has developed the High Throughput Virtual Slit (HTVSTM), robust all-reflective pupil slicing technology capable of replacing the slit in research-, commercial- and MIL-SPEC-grade spectrometer systems. In the simplest configuration, the HTVS allows optical designers to remove the lossy slit from pointsource spectrometers and widen the input slit of long-slit spectrometers, greatly increasing throughput without loss of spectral resolution or cross-dispersion information. The HTVS works by transferring etendue between image plane axes but operating in the pupil domain rather than at a focal plane. While useful for other technologies, this is especially relevant for spectroscopic applications by performing the same spectral narrowing as a slit without throwing away light on the slit aperture. HTVS can be implemented in all-reflective designs and only requires a small number of reflections for significant spectral resolution enhancement-HTVS systems can be efficiently implemented in most wavelength regions. The etendueshifting operation also provides smooth scaling with input spot/image size without requiring reconfiguration for different targets (such as different seeing disk diameters or different fiber core sizes). Like most slicing technologies, HTVS provides throughput increases of several times without resolution loss over equivalent slitbased designs. HTVS technology enables robust slit replacement in point-source spectrometer systems. By virtue of pupilspace operation this technology has several advantages over comparable image-space slicer technology, including the ability to adapt gracefully and linearly to changing source size and better vertical packing of the flux distribution. Additionally, this technology can be implemented with large slicing factors in both fast and slow beams and can easily scale from large, room-sized spectrometers through to small, telescope-mounted devices. Finally, this same technology is directly

  15. Reflections on Aesthetic Teaching

    ERIC Educational Resources Information Center

    Sotiropoulou-Zormpala, Marina

    2012-01-01

    This article examines how it is possible to use the aesthetic process to enrich teaching practices in preschool and elementary school education. What is under scrutiny is the aesthetic dimension of a core curricular subject, the ultimate goal being to achieve an understanding of curricular content through aesthetic learning processes. For this…

  16. Teaching: A Reflective Process

    ERIC Educational Resources Information Center

    German, Susan; O'Day, Elizabeth

    2009-01-01

    In this article, the authors describe how they used formative assessments to ferret out possible misconceptions among middle-school students in a unit about weather-related concepts. Because they teach fifth- and eighth-grade science, this assessment also gives them a chance to see how student understanding develops over the years. This year they…

  17. Reflections and New Directions

    ERIC Educational Resources Information Center

    Black, Paul; McCormick, Robert

    2010-01-01

    In introducing the articles in this issue, Black and McCormick are struck by two features. The first is that they comprise a rich set of resources for stimulating further thinking about tertiary education. The second, which follows from the first, is that they raise possibilities for further development of this field. They draw attention, in…

  18. Of possible cheminformatics futures.

    PubMed

    Oprea, Tudor I; Taboureau, Olivier; Bologa, Cristian G

    2012-01-01

    For over a decade, cheminformatics has contributed to a wide array of scientific tasks from analytical chemistry and biochemistry to pharmacology and drug discovery; and although its contributions to decision making are recognized, the challenge is how it would contribute to faster development of novel, better products. Here we address the future of cheminformatics with primary focus on innovation. Cheminformatics developers often need to choose between "mainstream" (i.e., accepted, expected) and novel, leading-edge tools, with an increasing trend for open science. Possible futures for cheminformatics include the worst case scenario (lack of funding, no creative usage), as well as the best case scenario (complete integration, from systems biology to virtual physiology). As "-omics" technologies advance, and computer hardware improves, compounds will no longer be profiled at the molecular level, but also in terms of genetic and clinical effects. Among potentially novel tools, we anticipate machine learning models based on free text processing, an increased performance in environmental cheminformatics, significant decision-making support, as well as the emergence of robot scientists conducting automated drug discovery research. Furthermore, cheminformatics is anticipated to expand the frontiers of knowledge and evolve in an open-ended, extensible manner, allowing us to explore multiple research scenarios in order to avoid epistemological "local information minimum trap". PMID:22207193

  19. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-01-01

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  20. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-04-04

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  1. Ageing and immortality.

    PubMed

    Rose, M R; Mueller, L D

    2000-11-29

    The concept of the force of natural selection was developed to explain the evolution of ageing. After ageing, however, comes a period in which mortality rates plateau and some individual organisms could, in theory, live forever. This late-life immortality has no presently agreed upon explanation. Two main theories have been offered. The first is heterogeneity within ageing cohorts, such that only extremely robust individuals survive ageing. This theory can be tested by comparisons of more and less robust cohorts. It can also be tested by fitting survival data to its models. The second theory is that late-life plateaus in mortality reflect the inevitable late-life plateau in the force of natural selection. This theory can be tested by changing the force of natural selection in evolving laboratory populations, particularly the age at which the force plateaus. This area of research has great potential for elucidating the overall structure of life-history evolution, particularly the interrelationship between the three life-history phases of development, ageing and immortality. PMID:11127912

  2. Magnesium and healthy aging.

    PubMed

    Veronese, Nicola; Zanforlini, Bruno Micael; Manzato, Enzo; Sergi, Giuseppe

    2015-01-01

    Magnesium (Mg) is relatively stable in the intracellular compartment, although decreases linearly with advancing age. This begs the question as to whether Mg could be used as biomarker of aging. A biomarker of aging is a biological parameter of an organism that, in the absence of disease, better predicts functional capability at a later age than the chronological age. Bone and muscle Mg content might be useful biomarkers, but the need for biopsies and the heterogeneous distribution of Mg in bones and muscles strongly limit the application of these methods in clinical practice. Similar considerations can be made for urinary Mg assessment, particularly after a loading test. Markers of Mg in blood seem fairly unreliable as biomarkers of aging since they are strongly dependent upon renal function, do not reflect the intracellular Mg status, and, in some investigations, are within normal ranges although other Mg parameters are not. Other investigations (e.g. nuclear magnetic resonance with fluorescent probes) seem to be promising, but their availability remains limited. PMID:26446714

  3. Reflecting on 80 years of excellence

    PubMed Central

    Savla, Ushma

    2004-01-01

    A small group of members of the American Society for Clinical Investigation began chatting in 1916 about the possibility of launching a new biomedical research journal. By October 1924, they managed to make the idea a reality with the publication of the first issue of the Journal of Clinical Investigation. Our 80th birthday seems an appropriate time to reflect on the history of biomedical science as it has been played out on our pages. PMID:15489943

  4. Reflections on conformal spectra

    NASA Astrophysics Data System (ADS)

    Kim, Hyungrok; Kravchuk, Petr; Ooguri, Hirosi

    2016-04-01

    We use modular invariance and crossing symmetry of conformal field theory to reveal approximate reflection symmetries in the spectral decompositions of the partition function in two dimensions in the limit of large central charge and of the four-point function in any dimension in the limit of large scaling dimensions Δ0 of external operators. We use these symmetries to motivate universal upper bounds on the spectrum and the operator product expansion coefficients, which we then derive by independent techniques. Some of the bounds for four-point functions are valid for finite Δ0 as well as for large Δ0. We discuss a similar symmetry in a large spacetime dimension limit. Finally, we comment on the analogue of the Cardy formula and sparse light spectrum condition for the four-point function.

  5. Structures for Facilitating Student Reflection

    ERIC Educational Resources Information Center

    Grossman, Robert

    2009-01-01

    The goal of this article is to describe a continuum of levels of reflection. It briefly focuses on Deanna Kuhn's research into the development of scientific thinking and Robert Kegan's Object-Subject Theory of Development applied to the problems of inspiring students to be able to reflect. Assignments for improving students' ability to reflect are…

  6. Reflections From a Fresnel Lens

    ERIC Educational Resources Information Center

    Keeports, David

    2005-01-01

    Reflection of light by a convex Fresnel lens gives rise to two distinct images. A highly convex inverted real reflective image forms on the object side of the lens, while an upright virtual reflective image forms on the opposite side of the lens. I describe here a set of laser experiments performed upon a Fresnel lens. These experiments provide…

  7. Reflective writing and nursing education.

    PubMed

    Craft, Melissa

    2005-02-01

    Reflective writing is a valued tool for teaching nursing students and for documentation, support, and generation of nursing knowledge among experienced nurses. Expressive or reflective writing is becoming widely accepted in both professional and lay publications as a mechanism for coping with critical incidents. This article explores reflective writing as a tool for nursing education.

  8. [Stress and optimal ageing].

    PubMed

    Gogol, Manfred

    2015-08-01

    Stress is a stimulus or incident which has an exogenic or endogenic influence on an organism and leads to a biological and/or psychological adaptation from the organism by adaptation. Stressors can be differentiated by the temporal impact (e.g. acute, chronic or acute on chronic), strength and quality. The consequences of stress exposure and adaptation can be measured at the cellular level and as (sub) clinical manifestations, where this process can be biologically seen as a continuum. Over the course of life there is an accumulation of stress incidents resulting in a diminution of the capability for adaptation and repair mechanisms. By means of various interventions it is possible to improve the individual capability for adaptation but it is not currently definitively possible to disentangle alterations due to ageing and the development of diseases. As a consequence the term "healthy ageing" should be replaced by the concept of "optimal ageing". PMID:26208575

  9. Aging Parents.

    ERIC Educational Resources Information Center

    Frazier, Billie H.

    This document contains a brief bibliography of peer-reviewed literature, with abstracts, on aging parents. It is one of 12 bibliographies on aging prepared by the National Agricultural Library for its "Pathfinders" series of publications. Topics covered by the other 11 bibliographies include adult children, dementia and Alzheimer's disease in the…

  10. The natural, the normal and the normative: contested terrains in ageing and old age.

    PubMed

    Jones, Ian Rees; Higgs, Paul F

    2010-10-01

    Improvements in health and longevity in countries such as the UK and USA have radically destabilised notions of ageing and old age. From the 19th century onwards the idea of a natural lifecourse following normatively understood stages ending in infirmity and death has been challenged by social and bio-medical developments. Breakthroughs in bio-gerontology and in bio-medicine have created the possibility of an increasingly differentiated idea of normal ageing. The potential to overcome or significantly reduce the age-associated effects of bodies growing older has led many social gerontologists to argue for a return to a more 'normatively' based conception of ageing and old age. This paper examines and outlines the tensions between these different discourses and points out that our understanding of the norm is also fast changing as it intersects with the somatic diversity inherent in contemporary consumer society. Drawing on the theoretical work of Ulrich Beck and Zygmunt Bauman, this paper argues that the normalization of diversity leads to a reworking of the idea of normativity which in turn is reflected in profound transformations at the level of institutional arrangements and legal systems. Such changes not only lead to more discussion of what is legally and socially acceptable but also potentially lead to greater calls for regulation concerning outcomes. In this paper we argue that we need to distinguish between the newly reconfigured domains of the natural, the normal and the normative now being utilised in the understanding of ageing if we are to understand this important field of health. PMID:20728972

  11. Reflections on replacement.

    PubMed

    Ryder, N B

    1993-01-01

    In the United States, the total fertility rate is about 1.9 births per woman, down from a peak of 3.2 a generation ago and below the replacement level of 2.1 children. The proportion of women who will never have children has risen from 8% a generation ago to approximately 18% in 1993. The increase in the proportion of women in the labor force, a proximate explanation of the recent decline in intended fertility, is expected to continue. The demographic consequence is declining population with an older age structure. A pronatalist policy to alleviate this outcome, through monetary transfers from taxpayers to potential parents, is not only unlikely to succeed, it is politically unfeasible. An alternative solution, immediately effective but politically unpalatable, would be a generous immigration policy. Even with replacement level fertility, the population is destined to become much older. This inevitable aging of the population should be countered by appropriate institutional transformations: 1) with lower fertility, a larger proportion of women will be available to participate in the labor force to generate taxes needed to support a larger number of pensioners; 2) the institutional practice of ascribing a dependent status to anyone above a particular age can be changed; 3) concerns that an older labor force will have an obsolete education (and fewer years of it) can be countered by changing access to education. Yet, the most serious question is not merely the net reproduction rate, but producing adequate numbers of new adult citizens with responsibility and technical training in the modern world. The fundamental process of socializing children may be jeopardized by replacing the full-time parent with the hired care-giver, the peer group, and the television set. The attenuation of the bonds between parent and child may devalue the worth of childbearing itself. These portentous consequences deserve consideration. PMID:8313953

  12. Possibilities with today's reproductive technologies.

    PubMed

    Johnson, S K

    2005-08-01

    Reproductive efficiency is critical to economic viability for cow/calf producers; however, very few producers take advantage of available reproductive technologies that can increase profitability. Today, more opportunities are available for producers who want to capture value from known genetics. Through the use of artificial insemination (AI), the average producer has access to a wide range of high-accuracy sires that can be selected to match production goals. Systems to synchronize estrus and ovulation can now produce pregnancy rates to a single fixed-timed AI that are 10-15% greater than those of the previous generation. Increased age and weight of calves at weaning is sufficient in some situations to pay for the cost of synchronization and AI. As a result of synchronization, more cows calve early the next year and in subsequent years of synchronization. The breeding season can be shortened without reducing end-of-season pregnancy rates, since synchronized cows have one more chance to conceive than unsynchronized cows in a 22-25 day interval. Cow nutrition can be more economically and precisely managed with a shorter breeding period. Producers that establish AI programs now will be prepared to take advantage of newly identified superior genetics or other technologies, e.g. sexed semen, when they become available. Trends towards more value-based marketing and improvements in pregnancy rates from synchronization systems, make this a key time to be aware of the possibilities using reproductive technologies. PMID:16002131

  13. Bidirectional reflectance of zinc oxide

    NASA Technical Reports Server (NTRS)

    Scott, R.

    1973-01-01

    This investigation was undertaken to determine original and useful information about the bidirection reflectance of zinc oxide. The bidirectional reflectance will be studied for the spectra between .25-2.5 microns and the hemisphere above the specimen. The following factors will be considered: (1) surface conditions; (2) specimen preparation; (3) specimen substrate, (4) polarization; (5) depolarization; (6) wavelength; and (7) angles of incident and reflection. The bidirectional reflectance will be checked by experimentally determined angular hemispherical measurements or hemispherical measurements will be used to obtain absolute bidirectional reflectance.

  14. [The reflective experience and education].

    PubMed

    Viniegra-Velázquez, Leonardo

    2008-01-01

    The reflective experience is proposed in this article as the way to approach the elaboration of knowledge. The concept of vital experience is proposed to make reference to the links with a great affective significance that characterizes each person in his/her relation with the world. Some considerations are made about perception with its affective, cognitive and evaluative components and its implications in the knowledge process. The idea of knowledge as the use and consumption of information is discussed. This idea that prevails at school corresponds with the passive perspective of education. We propose the idea of knowledge as an elaboration of the person in knowledge situation which originates the participative perspective of education. The characteristics of both perspectives of education are contrasted with respect to the role of theory and practice, the role of the professor and the student, the main purposes and the type of society that they aspire. The more relevant aspects of participative education are shown: the practice of criticism and self-criticism; the development of solid points of view about problem situations of experience, the development of methodological and practical aptitudes, with emphasis on medical education. Considerations are made about in what way the participative perspective concerns pre-graduate and post-graduate medical education and its possible incorporation to the programs.

  15. Placental measurements associated with intelligence quotient at age 7 years.

    PubMed

    Misra, D P; Salafia, C M; Charles, A K; Miller, R K

    2012-06-01

    We hypothesized that placental villous branching that is measured by disk chorionic plate expansion and disk thickness is correlated with factors also involved in regulation of branching growth of other fetal viscera (e.g. lung, kidney) including neuronal dendrites, and thus may be associated with variation in childhood intelligence quotient (IQ). IQ at age 7 years was assessed using the Wechsler Intelligence Scale for Children. Placental measures [placental weight (g), thickness (mm), chorionic plate surface diameters (cm), area (cm2), shape, and cord length and cord eccentricity] were independent variables in regression analyses of age 7-year IQ in 12,926 singleton term live born infants with complete placental data. Analyses were stratified on gender with adjustment for socioeconomic status, race, parity, gestational age, exact age at testing and centered parental ages. After adjustment for covariates, placental measurements were independently associated with IQ at age 7 years but results varied by gender. Chorionic plate diameters were only associated with higher IQ in girls. Placental thickness was positively associated with higher IQ for boys and girls. We have previously shown that placental measures affect age 7-year body mass index and diastolic blood pressure. Here we demonstrate that specific measures, placental chorionic plate diameters in girls and disk thickness, independent of gender, are correlated with age 7-year IQ. Further exploration of the possible interaction of these factors on the placental villous arborization reflected by the chorionic plate expansion and placental thickness that correlate with age 7-year IQ, as well as other age 7 somatic features as previously addressed, is indicated.

  16. Age-dependent diet choice in an avian top predator.

    PubMed

    Rutz, Christian; Whittingham, Mark J; Newton, Ian

    2006-03-01

    Age-dependent breeding performance is arguably one of the best-documented phenomena in ornithology. The existence of age-related trends has major implications for life-history theory, but the proximate reasons for these patterns remain poorly understood. It has been proposed that poor breeding performance of young individuals might reflect lack of foraging skills. We investigated this possibility in a medium-sized, powerful raptor-the northern goshawk Accipiter gentilis. Male goshawks are responsible for providing their females and their offspring with food. We hypothesized that young males may generally show poor breeding performance or even delay breeding, because they lack the experience to hunt efficiently-especially, their principal avian prey, the feral pigeon Columba livia. Our study exploited a rare 'natural experiment', the expansion phase of an urban population, where intraspecific interference was negligible and many young males bred successfully. This enabled us to examine the improvement of foraging skills in a larger sample of young individuals, and in more controlled conditions than usually possible. Using data from individually identified male breeders, we show that, consistent with our hypothesis, the proportion of pigeons in the diet increased significantly with male age, for at least the first three years of life. Other studies have shown a parallel increase in productivity, and a positive effect of a pigeon-rich diet on brood size and nestling condition, stressing the potential fitness relevance of this prey species for goshawks. Our results suggest a causal link between patterns of age-dependence in foraging ecology and reproductive performance. Furthermore, our study is, to our knowledge, the first demonstration that prey choice of breeders, which might reflect individual hunting skills, is age-dependent in a raptor. PMID:16537129

  17. Reflective Fourier ptychography.

    PubMed

    Pacheco, Shaun; Zheng, Guoan; Liang, Rongguang

    2016-02-01

    The Fourier ptychography technique in reflection mode has great potential applications in tissue imaging and optical inspection, but the current configuration either has a limitation on cut-off frequency or is not practical. By placing the imaging aperture stop outside the illumination path, the illumination numerical aperture (NA) can be greater than the imaging NA of the objective lens. Thus, the cut-off frequency achieved in the proposed optical system is greater than twice the objective's NA divided by the wavelength (2NAobj/λ ), which is the diffraction limit for the cut-off frequency in an incoherent epi-illumination configuration. We experimentally demonstrated that the synthesized NA is increased by a factor of 4.5 using the proposed optical concept. The key advantage of the proposed system is that it can achieve high-resolution imaging over a large field of view with a simple objective. It will have a great potential for applications in endoscopy, biomedical imaging, surface metrology, and industrial inspection. PMID:26891601

  18. Venus Highland Anomalous Reflectivity

    NASA Astrophysics Data System (ADS)

    Simpson, Richard A.; Tyler, G. L.; Häusler, B.; Mattei, R.; Patzold, M.

    2009-09-01

    Maxwell Montes was one of several unusually bright areas identified from early Venus radar backscatter observations. Pioneer Venus' orbiting radar associated low emissivity with the bright areas and established a correlation between reflectivity and altitude. Magellan, using an oblique bistatic geometry, showed that the bright surface dielectric constant was not only large but also imaginary -- i.e., the material was conducting, at least near Cleopatra Patera (Pettengill et al., Science, 272, 1996). Venus Express (VEX) repeated Magellan's bistatic observations over Maxwell, using the more conventional circular polarization carried by most spacecraft. Although VEX signal-to-noise ratio was lower than Magellan's, echoes were sufficiently strong to verify the Magellan conclusions near Cleopatra (see J. Geophys. Res., 114, E00B41, doi:10.1029/2008JE003156). Only about 40% of the surface at Cleopatra scatters specularly, opening the Fresnel (specular) interpretation model to question. Elsewhere in Maxwell, the specular percentage may be even lower. Nonetheless, the echo polarization is reversed throughout Maxwell, a result that is consistent with large dielectric constants and difficult to explain without resorting qualitatively (if not quantitatively) to specular models. VEX was scheduled to explore other high altitude regions when its S-Band (13-cm wavelength) radio system failed in late 2006, so further probing of high altitude targets awaits arrival of a new spacecraft.

  19. Reproductive ageing in women.

    PubMed

    Djahanbakhch, O; Ezzati, M; Zosmer, A

    2007-01-01

    The traditional view in respect to female reproduction is that the number of oocytes at birth is fixed and continuously declines towards the point when no more oocytes are available after menopause. In this review we briefly discuss the embryonic development of female germ cells and ovarian follicles. The ontogeny of the hypothalamic-pituitary-gonadal axis is then discussed, with a focus on pubertal transition and normal ovulatory menstrual cycles during female adult life. Biochemical markers of menopausal transition are briefly examined. We also examine the effects of age on female fertility, the contribution of chromosomal abnormalities of the oocyte to the observed decline in female fertility with age and the possible biological basis for the occurrence of such abnormalities. Finally, we consider the effects of maternal age on obstetric complications and perinatal outcome. New data that have the potential to revolutionize our understanding of mammalian oogenesis and follicular formation, and of the female reproductive ageing process, are also briefly considered.

  20. Spectral reflectance and photometric properties of selected rocks

    USGS Publications Warehouse

    Watson, Robert D.

    1971-01-01

    Studies of the spectral reflectance and photometric properties of selected rocks at the USGS Mill Creek, Oklahoma, remote sensing test site demonstrate that discrimination of rock types is possible through reflection measurements, but that the discrimination is complicated by surface conditions, such as weathering and lichen growth. Comparisons between fresh-broken, weathered, and lichen-covered granite show that whereas both degree of weathering and amount of lichen cover change the reflectance quality of the granite, lichen cover also considerably changes the photometric properties of the granite. Measurements of the spectral reflectance normal to the surface of both limestone and dolomite show limestone to be more reflective than dolomite in the wavelength range from 380 to 1550 nanometers. The reflectance difference decreases at view angles greater than 40° owing to the difference in the photometric properties of dolomite and limestone.

  1. Simulation Tool for GNSS Ocean Surface Reflections

    NASA Astrophysics Data System (ADS)

    Høeg, Per; von Benzon, Hans-Henrik; Durgonics, Tibor

    2015-04-01

    GNSS coherent and incoherent reflected signals have the potential of deriving large scale parameters of ocean surfaces, as barotropic variability, eddy currents and fronts, Rossby waves, coastal upwelling, mean ocean surface heights, and patterns of the general ocean circulation. In the reflection zone the measurements may derive parameters as sea surface roughness, winds, waves, heights and tilts from the spectral measurements. Previous measurements from the top of mountains and airplanes have shown such results leading. The coming satellite missions, CYGNSS, COSMIC-2, and GEROS on the International Space Station, are focusing on GNSS ocean reflection measurements. Thus, simulation studies highlighting the assumptions for the data retrievals and the precision and the accuracy of such measurements are of interest for assessing the observational method. The theory of propagation of microwaves in the atmosphere is well established, and methods for propagation modeling range from ray tracing to numerical solutions to the wave equation. Besides ray tracing there are propagation methods that use mode theory and a finite difference solution to the parabolic equation. The presented propagator is based on the solution of the parabolic equation. The parabolic equation in our simulator is solved using the split-step sine transformation. The Earth's surface is modeled with the use of an impedance model. The value of the Earth impedance is given as a function of the range along the surface of the Earth. This impedance concept gives an accurate lower boundary condition in the determination of the electromagnetic field, and makes it possible to simulate reflections and the effects of transitions between different mediums. A semi-isotropic Philips spectrum is used to represent the air-sea interaction. Simulated GPS ocean surface reflections will be presented and discussed based on different ocean characteristics. The spectra of the simulated surface reflections will be analyzed

  2. Functions and possible provenance of primordial proteins.

    PubMed

    Sommer, Andrei P; Miyake, Norimune; Wickramasinghe, N Chandra; Narlikar, Jayant V; Al-Mufti, Shirwan

    2004-01-01

    Nanobacteria or living nanovesicles are of great interest to the scientific community because of their dual nature: on the one hand, they appear as primal biosystems originating life; on the other hand, they can cause severe diseases. Their survival as well as their pathogenic potential is apparently linked to a self-synthesized protein-based slime, rich in calcium and phosphate (when available). Here, we provide challenging evidence for the occurrence of nanobacteria in the stratosphere, reflecting a possibly primordial provenance of the slime. An analysis of the slime's biological functions may lead to novel strategies suitable to block adhesion modalities in modern bacterial populations. PMID:15595742

  3. Behavior analysis and the study of human aging

    PubMed Central

    Derenne, Adam; Baron, Alan

    2002-01-01

    As the population of older adults continues to rise, psychologists along with other behavioral and social scientists have shown increasing interest in this age group. Although behavior analysts have contributed to research on aging, the focus has been on applications that remedy age-related deficits, rather than a concern with aging as a developmental process. In particular, there has been little interest in the central theoretical questions that have guided gerontologists. How does behavior change with advancing years, and what are the sources of those changes? We consider the possibility that this neglect reflects the long-standing commitment of behavior analysts to variables that can be experimentally manipulated, a requirement that excludes the key variable—age itself. We review the options available to researchers and present strategies that minimize deviations from the traditional features of behavior-analytic designs. Our comments are predicated on the view that aging issues within contemporary society are far too important for behavior analysts to ignore. PMID:22478383

  4. Immunological Aging

    EPA Science Inventory

    Immunosenescence is associated with an increased incidence and severity of infections with common pathogens, neoplastic disease and autoimmunity. In general, aging is associated with a decline in function at the cellular level, rather than cell loss, although thymic atrophy and ...

  5. Organizational Climate for Successful Aging.

    PubMed

    Zacher, Hannes; Yang, Jie

    2016-01-01

    Research on successful aging at work has neglected contextual resources such as organizational climate, which refers to employees' shared perceptions of their work environment. We introduce the construct of organizational climate for successful aging (OCSA) and examine it as a buffer of the negative relationship between employee age and focus on opportunities (i.e., beliefs about future goals and possibilities at work). Moreover, we expected that focus on opportunities, in turn, positively predicts job satisfaction, organizational commitment, and motivation to continue working after official retirement age. Data came from 649 employees working in 120 companies (M age = 44 years, SD = 13). We controlled for organizational tenure, psychological climate for successful aging (i.e., individuals' perceptions), and psychological and organizational age discrimination climate. Results of multilevel analyses supported our hypotheses. Overall, our findings suggest that OCSA is an important contextual resource for successful aging at work. PMID:27458405

  6. Organizational Climate for Successful Aging.

    PubMed

    Zacher, Hannes; Yang, Jie

    2016-01-01

    Research on successful aging at work has neglected contextual resources such as organizational climate, which refers to employees' shared perceptions of their work environment. We introduce the construct of organizational climate for successful aging (OCSA) and examine it as a buffer of the negative relationship between employee age and focus on opportunities (i.e., beliefs about future goals and possibilities at work). Moreover, we expected that focus on opportunities, in turn, positively predicts job satisfaction, organizational commitment, and motivation to continue working after official retirement age. Data came from 649 employees working in 120 companies (M age = 44 years, SD = 13). We controlled for organizational tenure, psychological climate for successful aging (i.e., individuals' perceptions), and psychological and organizational age discrimination climate. Results of multilevel analyses supported our hypotheses. Overall, our findings suggest that OCSA is an important contextual resource for successful aging at work.

  7. Variable area light reflecting assembly

    DOEpatents

    Howard, Thomas C.

    1986-01-01

    Device for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles.

  8. Variable area light reflecting assembly

    DOEpatents

    Howard, T.C.

    1986-12-23

    Device is described for tracking daylight and projecting it into a building. The device tracks the sun and automatically adjusts both the orientation and area of the reflecting surface. The device may be mounted in either a wall or roof of a building. Additionally, multiple devices may be employed in a light shaft in a building, providing daylight to several different floors. The preferred embodiment employs a thin reflective film as the reflecting device. One edge of the reflective film is fixed, and the opposite end is attached to a spring-loaded take-up roller. As the sun moves across the sky, the take-up roller automatically adjusts the angle and surface area of the film. Additionally, louvers may be mounted at the light entrance to the device to reflect incoming daylight in an angle perpendicular to the device to provide maximum reflective capability when daylight enters the device at non-perpendicular angles. 9 figs.

  9. Baffle system employing reflective surfaces

    NASA Astrophysics Data System (ADS)

    Linlor, W. I.

    1983-12-01

    Reflective baffles are proposed to reject off-axis light entering a telescope. Toroidal surfaces and adjacent cones are positioned so that off-axis rays make multiple reflections between these two surfaces. Meridional rays are reflected approximately parallel to the entering direction. Skew rays are reflected obliquely, but leave the telescope aperture. The range of incident angles for which these reflections are obtained is approximately 45 deg. A system is described that is designed specifically for the Space Shuttle Infrared Telescope Facility (SIRTF). Because of its reflective properties, the proposed baffle system rejects about 90 deg of the heat load from the SIRTF sunshade that would be absorbed in systems of conventional black baffles.

  10. Spectral reflectance measurements in the genus Sphagnum

    SciTech Connect

    Vogelmann, J.E.; Moss, D.M. . Complex Systems/Institute for the Study of Earth Oceans and Space)

    1993-09-01

    High-spectral resolution reflectance data were acquired in the laboratory for four species of Sphagnum (peat moss): S. cuspidatum, S. papillosum, S. fallax, and S. capillifolium. All four species had different spectral reflectance properties. Species differences were noted especially in the visible portion of the spectrum from 0.45 [mu]m to 0.70 [mu]m; some major spectral differences were also noted in the near infrared. Samples analyzed had much lower reflectance than typical green vegetation in the midinfrared region of the spectrum from 1.30 [mu]m to 2.40 [mu]m. In addition, Sphagnum had very pronounced water-related absorption features at about 1.00m [mu] and 1.20 [mu]m, unlike typical green vegetation. Spectral data acquired as samples were dried indicated large spectral increases with increasing dryness, especially in the midinfrared. Simulated Landsat Thematic Mapper 5/4 band ratio data were linearly related to the log of wet weight/dry weight. Reflectance from vegetation in the midinfrared region of the electromagnetic spectrum is strongly modified by water content. Peatlands are major sources of global methane and it has been found that methane evolution within these peatlands is related to water status within these peatlands is related to water status within the wetland. It may be possible to indirectly estimate methane flux using remote sensing data.

  11. [Care in Heidegger: an ontological possibility for nursing].

    PubMed

    de Oliveira, Marília de Fátima Vieira; Carraro, Telma Elisa

    2011-01-01

    Given the dimensions involving human care, this study aimed at providing a reflection on nursing care as an ontological possibility. In Heidegger we consider the concepts that underlie the foundation of his thought. These reflections offer theoretical resource that allows the recognition that live in the everyday actions of nursing is a challenge that leads us to a new look at the magnitude of care. However, the actions of care should not target only the perspective of a philosopher, but live with that thought in search of reflection, and find, scrutinizing everything you contribute to a nursing care committed to the right, with ethics, and with respect for others.

  12. Atlas of soil reflectance properties

    NASA Technical Reports Server (NTRS)

    Stoner, E. R.; Baumgardner, M. F.; Biehl, L. L.; Robinson, B. F.

    1979-01-01

    A compendium of soil spectral reflectance curves together with soil test results and site information is presented in an abbreviated manner listing those soil properties most important in influencing soil reflectance. Results are presented for 251 soils from 39 states and Brazil. A narrative key describes relationships between soil parameters and reflectance curves. All soils are classified according to the U.S. soil taxonomy and soil series name for ease of identification.

  13. Practicing Possibilities: Parents' Explanations of Unusual Events and Children's Possibility Thinking

    ERIC Educational Resources Information Center

    Nolan-Reyes, Charlotte; Callanan, Maureen A.; Haigh, Kirsten A.

    2016-01-01

    Young children tend to judge improbable events to be impossible, yet there is variability across age and across individuals. Our study examined parent-child conversations about impossible and improbable events and links between parents' explanations about those events and children's possibility judgments in a reasoning task. Regression analyses…

  14. Weak-shock reflection factors

    SciTech Connect

    Reichenbach, H.; Kuhl, A.L.

    1993-09-07

    The purpose of this paper is to compare reflection factors for weak shocks from various surfaces, and to focus attention on some unsolved questions. Three different cases are considered: square-wave planar shock reflection from wedges; square-wave planar shock reflection from cylinders; and spherical blast wave reflection from a planar surface. We restrict ourselves to weak shocks. Shocks with a Mach number of M{sub O} < 1.56 in air or with an overpressure of {Delta}{sub PI} < 25 psi (1.66 bar) under normal ambient conditions are called weak.

  15. Studies of the Reflection, Refraction and Internal Reflection of Light

    ERIC Educational Resources Information Center

    Lanchester, P. C.

    2014-01-01

    An inexpensive apparatus and associated experiments are described for studying the basic laws of reflection and refraction of light at an air-glass interface, and multiple internal reflections within a glass block. In order to motivate students and encourage their active participation, a novel technique is described for determining the refractive…

  16. Embodied Reflection and the Epistemology of Reflective Practice

    ERIC Educational Resources Information Center

    Kinsella, Elizabeth Anne

    2007-01-01

    Donald Schon's theory of reflective practice has been extensively referred to and has had enormous impact in education and related fields. Nonetheless, there continues to be tremendous conceptual and practical confusion surrounding interpretations of reflective practice and philosophical assumptions underlying the theory. In this paper, I argue…

  17. Calculating the reflected paths of radiation in high reflectivity enclosures

    SciTech Connect

    Shaughnessy, B.M.; Newborough, M.

    1999-07-01

    A novel method of calculating the reflected paths of radiation in Monte Carlo simulations is described. This method is well suited to high reflectivity (e.g., p > 0.5) systems, which tend to have strong directional and bidirectional characteristics. The prime advantage of the described approach is that it retains the inherent flexibility of the traditional Monte Carlo approach, but allows the paths of reflected radiation to be evaluated without the need for ray-surface intersection calculations. The paths of reflected radiation can therefore be evaluated much more rapidly, and Monte Carlo simulation times can be substantially reduced. Simulations of an enclosure containing an obstruction, exhibiting directional emission and reflection, and bi-directional reflection, are described and compared with solutions obtained by traditional Monte Carlo. For the studied cases, predictions from the new and traditional methods are in close agreement. Application of the new method resulted in computational speeds being improved by up to a factor of eight, depending upon the chosen reflection function (directional, specular, or bi-directional) and the desired accuracy of radiative exchange-factor calculation. For example, to achieve an average exchange-factor uncertainty of {+-} 10% (95% confidence), computational performance improvements of approximately twofold for the bi-directional case and threefold for the specular case were attained. For an uncertainty of {+-} 5% (99% confidence), the performance improvements increased to six and eightfold for bi-directional and specular reflection respectively.

  18. Postgraduate Education to Support Organisation Change: A Reflection on Reflection

    ERIC Educational Resources Information Center

    Stewart, Jim; Keegan, Anne; Stevens, Pam

    2008-01-01

    Purpose: This paper aims to explore how teaching and assessing reflective learning skills can support postgraduate practitioners studying organisational change and explores the challenges for tutors in assessing these journals. Design/methodology/approach: Assessment criteria were developed from the literature on reflective practice and…

  19. Age Rules

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.

    2015-10-01

    The ages of rocks from the lunar highlands vary widely, even for a single rock sample. This makes it difficult to quantitatively test ideas for early lunar differentiation and formation of the crust. Lars Borg and Amy Gaffney (Lawrence Livermore National Laboratory), and Charles Shearer (University of New Mexico) have devised a set of guidelines to apply to geochronological data that leads to a relative ranking of the reliability of the age determined for a sample. Applying their guidelines to existing data for lunar highland rocks shows an upper limit on rock ages between 4340 and 4370 million years. This is essentially the same as the so-called model ages of the formation of KREEP (a chemical component enriched in potassium, rare earth elements, and phosphorous) and of the formation of the deep source regions that melted to produce mare basalts. The numerous ages close to 4370 million years suggests a complicated and protracted cooling of the primordial lunar magma ocean or a widespread vigorous period of magmatic activity in the Moon.

  20. Modern Biological Theories of Aging

    PubMed Central

    Jin, Kunlin

    2010-01-01

    Despite recent advances in molecular biology and genetics, the mysteries that control human lifespan are yet to be unraveled. Many theories, which fall into two main categories: programmed and error theories, have been proposed to explain the process of aging, but neither of them appears to be fully satisfactory. These theories may interact with each other in a complex way. By understanding and testing the existing and new aging theories, it may be possible to promote successful aging. PMID:21132086

  1. Martian ages

    NASA Technical Reports Server (NTRS)

    Neukum, G.; Hiller, K.

    1981-01-01

    Four discussions are conducted: (1) the methodology of relative age determination by impact crater statistics, (2) a comparison of proposed Martian impact chronologies for the determination of absolute ages from crater frequencies, (3) a report on work dating Martian volcanoes and erosional features by impact crater statistics, and (4) an attempt to understand the main features of Martian history through a synthesis of crater frequency data. Two cratering chronology models are presented and used for inference of absolute ages from crater frequency data, and it is shown that the interpretation of all data available and tractable by the methodology presented leads to a global Martian geological history that is characterized by two epochs of activity. It is concluded that Mars is an ancient planet with respect to its surface features.

  2. Martian ages

    NASA Astrophysics Data System (ADS)

    Neukum, G.; Hiller, K.

    1981-04-01

    Four discussions are conducted: (1) the methodology of relative age determination by impact crater statistics, (2) a comparison of proposed Martian impact chronologies for the determination of absolute ages from crater frequencies, (3) a report on work dating Martian volcanoes and erosional features by impact crater statistics, and (4) an attempt to understand the main features of Martian history through a synthesis of crater frequency data. Two cratering chronology models are presented and used for inference of absolute ages from crater frequency data, and it is shown that the interpretation of all data available and tractable by the methodology presented leads to a global Martian geological history that is characterized by two epochs of activity. It is concluded that Mars is an ancient planet with respect to its surface features.

  3. Plutonium aging

    SciTech Connect

    Olivas, J.D.

    1999-03-01

    The author describes the plutonium aging program at the Los Alamos National Laboratory. The aging of plutonium components in the US nuclear weapons stockpile has become a concern due to several events: the end of the cold war, the cessation of full scale underground nuclear testing as a result of the Comprehensive Test Ban Treaty (CTBT) and the closure of the Rocky Flats Plant--the site where the plutonium components were manufactured. As a result, service lifetimes for nuclear weapons have been lengthened. Dr. Olivas will present a brief primer on the metallurgy of plutonium, and will then describe the technical approach to ascertaining the long-term changes that may be attributable to self-radiation damage. Facilities and experimental techniques which are in use to study aging will be described. Some preliminary results will also be presented.

  4. Troubling Muddy Waters: Problematizing Reflective Practice in Global Medical Education.

    PubMed

    Naidu, Thirusha; Kumagai, Arno K

    2016-03-01

    The idea of exporting the concept of reflective practice for a global medical education audience is growing. However, the uncritical export and adoption of Western concepts of reflection may be inappropriate in non-Western societies. The emphasis in Western medical education on the use of reflection for a specific end--that is, the improvement of individual clinical practice--tends to ignore the range of reflective practice, concentrating on reflection alone while overlooking critical reflection and reflexivity. This Perspective places the concept of reflective practice under a critical lens to explore a broader view for its application in medical education outside the West. The authors suggest that ideas about reflection in medicine and medical education may not be as easily transferable from Western to non-Western contexts as concepts from biomedical science are. The authors pose the question, When "exporting" Western medical education strategies and principles, how often do Western-trained educators authentically open up to the possibility that there are alternative ways of seeing and knowing that may be valuable in educating Western physicians? One answer lies in the assertion that educators should aspire to turn exportation of educational theory into a truly bidirectional, collaborative exchange in which culturally conscious views of reflective practice contribute to humanistic, equitable patient care. This discussion engages in troubling the already-muddy waters of reflective practice by exploring the global applicability of reflective practice as it is currently applied in medical education. The globalization of medical education demands critical reflection on reflection itself. PMID:26630601

  5. Understanding aging.

    PubMed

    Strehler, B L

    2000-01-01

    Enormous advances in our understanding of human aging have occurred during the last 50 yr. From the late 19th to the mid-20th centuries only four comprehensive and important sources of information were available: 1. August Weismann's book entitled Essays on Heredity and Kindred Biological Problems (the first of these essays dealt with The Duration of Life; 1). Weissmann states (p. 10) "In the first place in regulating the length of life, the advantage to the species, and not to the individual, is alone of any importance. This must be obvious to any one who has once thoroughly thought out the process of natural selection_". 2. A highly systematized second early source of information on aging was the collection of essays edited by Cowdry and published in 1938. This 900+ page volume contains 34 chapters and was appropriately called Problems of Aging. 3. At about the same time Raymond Pearl published his book on aging (2). Pearl believed that aging was the indirect result of cell specialization and that only the germ line was resistant to aging. Unfortunately Pearl died in the late 1930s and is largely remembered now for having been the founding editor of Quarterly Review of Biology while he was at the Johns Hopkins University, this author's alma mater. 4. Alexis Carrel wrote a monumental scientific and philosophical book, Man, the Unknown (3). Carrel believed that he had demonstrated that vertebrate cells could be kept in culture and live indefinitely, a conclusion challenged by others (more on this later). PMID:22351262

  6. Internal reflection sensors with high angular resolution

    NASA Astrophysics Data System (ADS)

    Shavirin, I.; Strelkov, O.; Vetskous, A.; Norton-Wayne, L.; Harwood, R.

    1996-07-01

    We discuss the use of total internal reflection for the production of sensors with high angular resolution. These sensors are intended for measurement of the angle between a sensor's axis and the direction to a source of radiation or reflecting object. Sensors of this type are used in controlling the position of machine parts in robotics and industry, orienting space vehicles and astronomic devices in relation to the Sun, and as autocollimators for checking angles of deviation. This kind of sensor was used in the Apollo space vehicle some 20 years ago. Using photodetectors with linear and area CCD arrays has opened up new application possibilities for appropriately designed sensors. A generalized methodology is presented applicable to a wide range of tasks. Some modifications that can improve the performance of the basic design are described.

  7. The aging heart.

    PubMed

    Klausner, S C; Schwartz, A B

    1985-02-01

    Pathologic studies of the myocardium and valvular structures have failed to provide convincing evidence of gross or microscopic changes that can be ascribed to aging alone. Lipofuscin accumulation and basophilic degeneration in cardiac muscle cells appear to be the most consistent findings associated with aging, but they are found in other conditions. Without doubt, pathologic changes in the myocardium, valves, and coronary arteries are found more frequently in the hearts of elderly persons, but those changes are caused by disease processes associated with an aging population rather than the aging process itself. Both the sinus and atrioventricular nodes decrease in size with age owing to a loss of cellularity. These structures become infiltrated with collagen, elastic tissue, and reticular fibers. Some have found infiltration also with fat. Amyloid deposition, basophilic degeneration of cells, and lipofuscin accumulation occur but probably do not cause functional abnormalities. Similar but less dramatic changes occur in the bundle of His and individual bundle branches. Most of the data suggests that these aging changes are not due to vascular insufficiency. Age-related changes in intrinsic mechanical function have been identified as a prolongation of contraction duration, decreased inotropic responses to catecholamines and cardiac glycosides, and an increase in mechanical refractoriness. Other possible age-related changes include alterations in relaxation, which may or may not be independent of the prolongation of contraction, and changes in the viscoelastic properties of cardiac muscle. When examined in the context of the components of a model of excitation-contraction coupling, changes in action potential duration and the function of the sarcoplasmic reticulum emerge as the most likely bases for the changes. The electrical characteristics of sinus, atrioventricular, and His-Purkinje cells as well as atrial and ventricular muscle cells change with age. The sinus

  8. Resist Characterization On Reflecting Substrates

    NASA Astrophysics Data System (ADS)

    Hayes, John; Bell, William R.; Ferguson, Richard; Neureuther, Andrew R.

    1986-07-01

    The bottleneck of quantitative characterization of resist materials is being relieved by the introduction of a commercial system with multiple channel capabilities working directly on silicon wafers. This convenience for the process engineer comes at considerable inconvenience in data analysis, primarily due to exposure standing wave effects from substrate reflection. On silicon, for example, an exposure variation of a factor of 8 occurs over a vertical distance of 65 nm within the resist. Data from this very thin layer can span almost the entire range of exposure state M of the resist and two orders of magnitude change in development rates. Experimental and software techniques developed in a benchmark study of the well characterized Kodak 820 resist are reported. Several software techniques were established for data analysis. A depth-dependent filtering technique was used to improve the signal-to-noise ratio of the rate vs depth data from the slowly developing channels. This noise is due to the high sampling rates, which are necessary to simultaneously monitor the most rapidly developing areas. A post processor for SAMPLE was developed to process the normal output of exposure state M versus depth and generate M values for the exposures specified in the data from the measurement system. A three column vector of development rate R, exposure state M and depth z is then generated for plotting R(M,z) and numerically fitting algebraic models. Measurements and data reduction were made on silicon wafers with various thin film coatings. A hard-baked resist coating was sufficiently absorbing that very little oscillation in the development rate with depth was observed. For aluminum coatings, it was not possible to get good thickness vs time or rate data. The rate versus depth on bare silicon wafers could be made well behaved after filtering. The resulting R(M,z) curve for bare silicon was somewhat noisy. Thus the use of a hard-baked coating is indicated in practice for

  9. Diet and healthy ageing.

    PubMed

    McKevith, Brigid

    2005-12-01

    In the future there will be more people aged 65 years and over ('older adults'). Although the exact mechanisms underlying normal ageing are not fully understood, ageing is generally associated with an increase in chronic diseases, such as cardiovascular disease, diabetes, cancer and osteoporosis. It is becoming clear that it is possible to prevent, slow or reverse the onset of many these by modifying lifestyle factors such as diet. Studies of older adults in a range of countries have highlighted a number of areas in which dietary quality could be improved. It is important to identify dietary patterns in addition to specific dietary components that offer protection against chronic disease. The challenge in the area of diet and healthy ageing is twofold: first, there is a need to improve the diet of older adults; and second, as most chronic diseases begin earlier in life, there is a need to encourage other age groups to adapt their diet so they can enter old age in better health.

  10. [Sexuality in aging].

    PubMed

    Berner, Yitshal N

    2002-07-01

    During aging, impairment in many physiological functions is manifested. This is exhibited in sexual functioning, which is an intricate interaction involving a number of systems: endocrinal, motor, sensor, physical and sensual. Sexual activity is a component of the well-being of the individual, while sexuality is part of self-identity at any age. Sexual activity is a primary base to human relations, and it is a basic right of every person in society. Sexuality and sexual activity are considered to be part of youth, hence, the combination of sexuality and aging is considered strange. In many instances, sexual activity in the elderly is considered exceptional and possibly requiring certain intervention of the society establishment. Recent technological advances enable sexual activity, despite physiological and even anatomical shortcomings. Knowledge of the changes in sexual activity with aging, as well as having open communication on the subject, are the best tools for maintaining sexual activity with appropriate limitation during aging. The purpose of this short review is to present the different aspects of sexuality and sexual activity in aging.

  11. Children's Literature-Some Reflections.

    ERIC Educational Resources Information Center

    Root, Shelton L., Jr.

    Ten reflections may be made regarding children's literature and its teaching. The reflections are as follows: (1) Teachers can make a profound difference in the lives of students and should attempt to do so. (2) Teachers of children's literature are a badly fragmented lot and need a common meeting ground where they can share their thinking. (3)…

  12. Reflectivity in Supervision and Teaching.

    ERIC Educational Resources Information Center

    Pavlovic, Steve; Friedland, Billie

    This paper reports on a strategy for encouraging preservice teachers to use reflective techniques when developing lesson plans. A focus on reflective practice incorporates and integrates the minimal teaching competencies required by West Virginia State Teacher Certification. Practicum students must provide evidence demonstrating at least minimal…

  13. Flexible Bistable Cholesteric Reflective Displays

    NASA Astrophysics Data System (ADS)

    Yang, Deng-Ke

    2006-03-01

    Cholesteric liquid crystals (ChLCs) exhibit two stable states at zero field condition-the reflecting planar state and the nonreflecting focal conic state. ChLCs are an excellent candidate for inexpensive and rugged electronic books and papers. This paper will review the display cell structure,materials and drive schemes for flexible bistable cholesteric (Ch) reflective displays.

  14. Ethical Reflections on Becoming Teachers

    ERIC Educational Resources Information Center

    Joseph, Pamela Bolotin

    2016-01-01

    This study analyzes narratives written in a culminating graduate seminar on reflective practice by 36 new secondary teachers who were asked to consider their moral beliefs, moral values and system of ethics as they reflected on their recent student teaching experiences. The findings explore how the participants depicted their constructed moral…

  15. Reflections on Justice in Schooling

    ERIC Educational Resources Information Center

    First, Patricia F.

    2012-01-01

    This article is a reflection on the concept of justice as practiced in the public schools in the United States. Examples of justice denied or misconstrued are included. Cases, stories, and concepts invite educational leaders to reflect anew on delivering justice in education to all children. Underlying the article is the belief that understanding…

  16. Can Reflective Practice Be Taught?

    ERIC Educational Resources Information Center

    Edwards, Gail; Thomas, Gary

    2010-01-01

    Almost ubiquitous in discourses about the development of teachers, reflective practice describes the process that occurs when persons are apprenticed to any meaningful activity. But reflective practice is a descriptive term for that process: it does not imply that the process is itself open to dissection and instruction. We contend that mistaken…

  17. Classroom Renewal through Teacher Reflection.

    ERIC Educational Resources Information Center

    Schoenbach, Ruth

    1994-01-01

    Describes a high school staff development project that successfully improved student communication skills. In the project, teacher reflection was critical in changing classroom practice, and it led to improved student outcomes. The article describes the project, vehicles for supporting teacher reflection, and lessons learned in using reflective…

  18. Vulnerable Neural Systems and the Borderland of Brain Aging and Neurodegeneration

    PubMed Central

    Jagust, William

    2013-01-01

    Brain aging is characterized by considerable heterogeneity, including varying degrees of dysfunction in specific brain systems, notably a medial temporal lobe memory system, and a frontostriatal executive system. These same systems are also affected by neurodegenerative diseases of late life. Recent work using techniques for presymptomatic detection of disease in cognitively normal older people has shown that some of the late life alterations in cognition, neural structure and function attributed to aging probably reflects early neurodegeneration. However, it has become clear that these same brain systems are also vulnerable to aging itself in the absence of even subtle disease. Thus, fundamental systemic limitations appear to confer vulnerability of these neural systems to a variety of insults, including those recognized as typical disease and those that are attributed to age. By focusing on the fundamental causes of neural system vulnerability, the prevention or treatment of a wide range of late-life neural dysfunction might be possible. PMID:23352159

  19. Aging Secret

    ERIC Educational Resources Information Center

    Journal of College Science Teaching, 2005

    2005-01-01

    The canny world of advertising has caught on to the free radical theory of aging, marketing a whole array of antioxidants for preventing anything from wrinkles to dry hair to reducing the risk of heart disease--promising to help slow the hands of time. Working with genetically engineered mice--to produce a natural antioxidant enzyme called…

  20. Gay Aging

    ERIC Educational Resources Information Center

    Haber, David

    2009-01-01

    The oldest of the baby boomers (boomers) were age 63 in 2009 and on the verge of retirement. This cohort has had a history of making societal changes throughout its life cycle, and it is unlikely that retirement, as we know it, will remain unscathed. This article highlights two events--the Stonewall Inn riots and two prominent professional…

  1. Geoacoustic reflectivity inversion: A Bayesian approach

    NASA Astrophysics Data System (ADS)

    Dettmer, Jan

    Propagation and reverberation of acoustic fields in shallow water depend strongly on the spatial variability of seabed geoacoustic parameters; and lack of knowledge of seabed variability is often a limiting factor in acoustic modelling applications. However, direct sampling (e.g., coring) of vertical and lateral variability is expensive and laborious, and matched-field and other long-range inversion methods fail to provide sufficient resolution. This thesis develops a new joint time/frequency domain inversion for high-resolution single-bounce reflection data. The inversion approach has the potential to resolve fine-scale sediment profiles over small seafloor footprints (˜100 m). The approach utilises sequential Bayesian inversion of time- and frequency-domain reflectivity data, employing ray-tracing inversion for reflection travel times and a layer-packet stripping method for spherical-wave reflection coefficient inversion. Rigorous uncertainty estimation is of key importance to yield high quality inversion results. Quantitative geoacoustic uncertainties are provided by a nonlinear Gibbs sampling approach together with full data error covariance estimation (including non-stationary effects). The small footprint of the measurement technique combined with the rigorous inversion of both time and frequency domain data provides a powerful new tool to examine seabed structure on finer scales than heretofore possible. The Bayesian inversion is applied to two data sets collected on the Malta Plateau and the Strait of Sicily during the SCARAB98 experiment. The first application aims to recover multi-layered seabed structure and the second application recovers density and sound velocity gradient structure in the uppermost sediment layer. An interesting new method of deriving reflectivity data from ambient noise measurements is briefly considered in simulation to examine the resolving power and limits of the approach.

  2. Lithosphere-asthenosphere P-wave reflectivity across Australia

    NASA Astrophysics Data System (ADS)

    Kennett, B. L. N.

    2015-12-01

    A direct image of P-wave reflectivity in the lithosphere and asthenosphere beneath seismic stations is extracted from stacked autocorrelograms of continuous component records. The autocorrelograms emphasise near vertically travelling waves, so that multiples are more muted than in receiver function studies and it is possible to work at higher frequencies than for receiver functions. Across a wide range of geological environments in Australia, in the 0.5-4.0 Hz frequency band, distinct reflections are seen in the crust underlain by weaker reflectivity in the lithosphere and asthenosphere. The base of crustal reflectivity fits well with Moho estimates from other classes of information. Few mantle reflectors have been seen in conventional reflection profiling at frequencies above 10 Hz; the presence of reflections in the 0.5-4.0 Hz band suggests variations on vertical scales of a few hundred metres with amplitudes of the order of 1%. There are slight indications of a change of reflection character in the lower part of the lithosphere in the transition to the asthenosphere. At a few stations there is a very clear lamination at asthenospheric depth, as well as reflections from the base of the S wave low velocity zone. Reflection bands often occur at depths where discontinuities have been inferred from S wave receiver function work at the same station, but would not by themselves be distinctive of a mid-lithosphere discontinuity.

  3. Active Aging Promotion: Results from the Vital Aging Program

    PubMed Central

    Caprara, Mariagiovanna; Molina, María Ángeles; Schettini, Rocío; Santacreu, Marta; Orosa, Teresa; Mendoza-Núñez, Víctor Manuel; Rojas, Macarena; Fernández-Ballesteros, Rocío

    2013-01-01

    Active aging is one of the terms in the semantic network of aging well, together with others such as successful, productive, competent aging. All allude to the new paradigm in gerontology, whereby aging is considered from a positive perspective. Most authors in the field agree active aging is a multidimensional concept, embracing health, physical and cognitive fitness, positive affect and control, social relationships and engagement. This paper describes Vital Aging, an individual active aging promotion program implemented through three modalities: Life, Multimedia, and e-Learning. The program was developed on the basis of extensive evidence about individual determinants of active aging. The different versions of Vital Aging are described, and four evaluation studies (both formative and summative) are reported. Formative evaluation reflected participants' satisfaction and expected changes; summative evaluations yielded some quite encouraging results using quasi-experimental designs: those who took part in the programs increased their physical exercise, significantly improved their diet, reported better memory, had better emotional balance, and enjoyed more cultural, intellectual, affective, and social activities than they did before the course, thus increasing their social relationships. These results are discussed in the context of the common literature within the field and, also, taking into account the limitations of the evaluations accomplished. PMID:23476644

  4. Organizational Climate for Successful Aging

    PubMed Central

    Zacher, Hannes; Yang, Jie

    2016-01-01

    Research on successful aging at work has neglected contextual resources such as organizational climate, which refers to employees’ shared perceptions of their work environment. We introduce the construct of organizational climate for successful aging (OCSA) and examine it as a buffer of the negative relationship between employee age and focus on opportunities (i.e., beliefs about future goals and possibilities at work). Moreover, we expected that focus on opportunities, in turn, positively predicts job satisfaction, organizational commitment, and motivation to continue working after official retirement age. Data came from 649 employees working in 120 companies (Mage = 44 years, SD = 13). We controlled for organizational tenure, psychological climate for successful aging (i.e., individuals’ perceptions), and psychological and organizational age discrimination climate. Results of multilevel analyses supported our hypotheses. Overall, our findings suggest that OCSA is an important contextual resource for successful aging at work. PMID:27458405

  5. Utilizing Calibrated GPS Reflected Signals to Estimate Soil Reflectivity and Dielectric Constant: Results from SMEX02

    NASA Technical Reports Server (NTRS)

    Katzberg, Stephen J.; Torres, Omar; Grant, Michael S.; Masters, Dallas

    2006-01-01

    Extensive reflected GPS data was collected using a GPS reflectometer installed on an HC130 aircraft during the Soil Moisture Experiment 2002 (SMEX02) near Ames, Iowa. At the same time, widespread surface truth data was acquired in the form of point soil moisture profiles, areal sampling of near-surface soil moisture, total green biomass and precipitation history, among others. Previously, there have been no reported efforts to calibrate reflected GPS data sets acquired over land. This paper reports the results of two approaches to calibration of the data that yield consistent results. It is shown that estimating the strength of the reflected signals by either (1) assuming an approximately specular surface reflection or (2) inferring the surface slope probability density and associated normalization constants give essentially the same results for the conditions encountered in SMEX02. The corrected data is converted to surface reflectivity and then to dielectric constant as a test of the calibration approaches. Utilizing the extensive in-situ soil moisture related data this paper also presents the results of comparing the GPS-inferred relative dielectric constant with the Wang-Schmugge model frequently used to relate volume moisture content to dielectric constant. It is shown that the calibrated GPS reflectivity estimates follow the expected dependence of permittivity with volume moisture, but with the following qualification: The soil moisture value governing the reflectivity appears to come from only the top 1-2 centimeters of soil, a result consistent with results found for other microwave techniques operating at L-band. Nevertheless, the experimentally derived dielectric constant is generally lower than predicted. Possible explanations are presented to explain this result.

  6. Anisotropy as cause for polarity reversals of D" reflections

    NASA Astrophysics Data System (ADS)

    Thomas, Christine; Wookey, James

    2013-04-01

    Seismic reflections from structures in the D" region - the lowest 200-400 km of the Earth's mantle - can provide information on the velocity contrast of this region. Using the waveforms and polarities of the D" reflections in P and S-waves we can distinguish between different possibilities that may cause the observed structures, such as phase transitions, aligned material or thermal anomalies. Here we use recordings of seismic events that reflect beneath the Caribbean and Eurasia. Both P and S reflected waves are used where possible. The source-receiver combinations provide reflections off D" in two fast velocity regions. Under Eurasia three crossing paths are used. The polarities of reflections in both regions differ and can therefore help to further discriminate the cause for the observed reflections. In one region, we find apparent positive S-velocity contrasts but negative P-wave velocity contrasts for the D" reflector. In the second fast velocity region we detect positive P- and S-wave velocity contrasts in two orthogonal paths crossing in the lowermost mantle indicating a different scenario for the structures in D". A third intersecting path shows negative polarities of the reflected P wave. One possible explanation to reconcile observations in both regions is a phase transition from perovskite to post-perovskite with 12 percent of alignment in the post-perovskite phase. Depending on the travel direction of the waves with respect to the flow direction in the lower mantle, apparent positive or negative velocity jumps (reflectivity) can be expected. Other isotropic and anisotropic models are tested but cannot fully explain the range of observations we find in the data.

  7. Perceptions of and Attitudes towards Ageing in Zambia

    ERIC Educational Resources Information Center

    Mapoma, Christopher C.; Masaiti, Gift

    2012-01-01

    This paper reflects part of the wider outlook on ageing in general in Zambia and was intended to investigate perceptions of and attitudes towards the aged and ageing in Zambia by members of the community who, by definition and chronologically are not classified as aged i.e. not yet 60 years and over. Focus Group Discussions (FGD) were used to…

  8. The near-infrared continuum emission of visual reflection nebulae

    NASA Technical Reports Server (NTRS)

    Sellgren, K.

    1984-01-01

    In the past, reflection nebulae have provided an astrophysical laboratory well suited for the study of the reflection properties of interstellar dust grains at visual and ultraviolet wavelengths. The present investigation is concerned with observations which were begun with the objective to extend to near-infrared wavelengths the study of grains in reflection. Observations of three classical visual reflection nebulae were conducted in the wavelength range from 1.25 to 2.2 microns, taking into account NGC 7023, 2023, and 2068. All three nebulae were found to have similar near-infrared colors, despite widely different colors of their illuminating stars. The brightness level shown by two of the nebulae at 2.2 microns was too high to be easily accounted for on the basis of reflected light. Attention is given to a wide variety of possible emission mechanisms.

  9. Near-100 percent Bragg Reflectivity of X-rays

    SciTech Connect

    Y Shvydko; S Stoupin; V Blank; S Terentyev

    2011-12-31

    Ultrahigh-reflectance mirrors are essential optical elements of the most sophisticated optical instruments devised over the entire frequency spectrum. In the X-ray regime, super-polished mirrors with close to 100% reflectivity are routinely used at grazing angles of incidence. However, at large angles of incidence, and particularly at normal incidence, such high reflectivity has not yet been achieved. Here, we demonstrate by direct measurements that synthetic, nearly defect-free diamond crystals reflect more than 99% of hard X-ray photons backwards in Bragg diffraction, with a remarkably small variation in magnitude across the sample. This is a quantum leap in the largest reflectivity measured to date, which is at the limit of what is theoretically possible. This accomplishment is achieved under the most challenging conditions of normal incidence and with extremely hard X-ray photons.

  10. Polarization-ratio reflectance measurements in the extreme ultraviolet.

    PubMed

    Brimhall, N; Heilmann, N; Ware, M; Peatross, J

    2009-05-01

    We demonstrate a technique for determining optical constants of materials in the extreme UV from the ratio of p-polarized to s-polarized reflectance. The measurements are based on laser-generated high-order harmonics, which have easily rotatable linear polarization but that are prone to brightness fluctuations and systematic drifts during measurement. Rather than measure the absolute reflectance, we extract the optical constants of a material from the ratio of p-polarized to s-polarized reflectance at multiple incident angles. This has the advantage of dividing out long-term fluctuations and possible systematic errors. We show that the reflectance ratio is as sensitive as the absolute reflectance to material optical properties.

  11. Reflective Practice and Its Implications for Pharmacy Education

    PubMed Central

    Bosnic-Anticevich, Sinthia; Smith, Lorraine

    2014-01-01

    Pharmacy students require critical-thinking and problem-solving skills to integrate theory learned in the classroom with the complexities of practice, yet many pharmacy students fall short of acquiring these skills.1-2 Reflective practice activities encourage learning from the student’s own experiences and those of others, and offer a possible solution for the integration of knowledge-based curricula with the ambiguities of practice, as well as enhance communication and collaboration within a multidisciplinary team. Although reflective practices have been embraced elsewhere in health professions education, their strengths and shortcomings need to be considered when implementing such practices into pharmacy curricula. This review provides an overview of the evolution of theories related to reflective practice, critically examines the use of reflective tools (such as portfolios and blogs), and discusses the implications of implementing reflective practices in pharmacy education. PMID:24558286

  12. Reflective practice and its implications for pharmacy education.

    PubMed

    Tsingos, Cherie; Bosnic-Anticevich, Sinthia; Smith, Lorraine

    2014-02-12

    Pharmacy students require critical-thinking and problem-solving skills to integrate theory learned in the classroom with the complexities of practice, yet many pharmacy students fall short of acquiring these skills.(1-2) Reflective practice activities encourage learning from the student's own experiences and those of others, and offer a possible solution for the integration of knowledge-based curricula with the ambiguities of practice, as well as enhance communication and collaboration within a multidisciplinary team. Although reflective practices have been embraced elsewhere in health professions education, their strengths and shortcomings need to be considered when implementing such practices into pharmacy curricula. This review provides an overview of the evolution of theories related to reflective practice, critically examines the use of reflective tools (such as portfolios and blogs), and discusses the implications of implementing reflective practices in pharmacy education.

  13. Tribal Aging Programs: A Basic Guide.

    ERIC Educational Resources Information Center

    National Indian Council on Aging, Albuquerque, NM.

    A national training session for administrators of tribal aging programs held by the National Indian Council on Aging in November 1979 was the basis for the training manual. The seven chapter titles reflect workshop topics with the text of each chapter incorporating material presented in the workshops and examples of model programs on reservations.…

  14. [Medical drug abuse and aging].

    PubMed

    Nubukpo, Philippe; Clément, Jean-Pierre

    2013-09-01

    Drug addiction is often underestimated among the aged. Opiate drugs (mostly pain killers) are the most frequently implicated in drug addiction after benzodiazepines (BZD) in the aged. The subjects aged of 65 years or more are the most represented among the BZD users in France. Frequency of BZD use varies according to various studies from 39 to 55% in this age group. Leading a lonely life is associated with the use of psychotropic drugs among retired people (OR=1.7). Vulnerability at this age must take into account not only polypathology, but also the faster aging of a minority of the population under opiate drugs substitution treatment (OST), more subjects to drugs interaction. Drug addiction among elderly often reflects the drift of "lawful" doctor's instructions that leads to an increase in drugs use. The difficulty has to do with a lack of specificity of diagnosis of addiction at this age, but perhaps also with physicans'instructions in the aged. Some authors suggest that continued and prolonged use should be considered the main criterion for BZD addiction at this age, with or without increase in doses and failed attempt at cessation. Besides, the prescription of BZD increases after retirement and loneliness.

  15. Differential phase measurements of D-region partial reflections

    NASA Technical Reports Server (NTRS)

    Wiersma, D. J.; Sechrist, C. F., Jr.

    1972-01-01

    Differential phase partial reflection measurements were used to deduce D region electron density profiles. The phase difference was measured by taking sums and differences of amplitudes received on an array of crossed dipoles. The reflection model used was derived from Fresnel reflection theory. Seven profiles obtained over the period from 13 October 1971 to 5 November 1971 are presented, along with the results from simultaneous measurements of differential absorption. Some possible sources of error and error propagation are discussed. A collision frequency profile was deduced from the electron concentration calculated from differential phase and differential absorption.

  16. Aging & Health.

    PubMed

    2016-09-01

    By 2050 an estimated 83.7 million Americans will be ages sixty-five and older, up from 40.3 million in 2010. The shock wave of aging Americans will have profound implications for older people, their families, health care providers, and the economy. Researchers, policy makers, health care leaders, and others are designing responses to the challenges these actuarial shifts will create. For example, delivering health care at home could help keep more older Americans out of costly emergency departments and nursing homes. But such steps require more health care providers, a broader distribution of providers than currently exists, and better use of the resources we have. PMID:27605632

  17. Reflectance anisotropy for nadir observations of coniferous forest canopies

    SciTech Connect

    Syren, P. . Lab. of Remote Sensing)

    1994-07-01

    Nadir-viewed reflectances from forest canopies in four spectral bands, centered at 485 nm, 654 nm, 841 nm, and 1,676 nm were measured at different sun angles. Reflectances were measured made from a helicopter ca. 10 km NE of Stockholm, Sweden, over mature and young stands of Scotch pine (Pinus sylvestris) and Norway spruce (Picea abies). The results show a significant increase in nadir reflectance with decreasing solar zenith angle. On the average, reflectance factors increased by 1--2% for each degree of decreasing solar zenith angle. Band ratios showed that there is a disproportional reflectance response in several of the spectral bands at varying zenith angles, differently expressed according to stand type and age. Within the solar zenith angle interval 30--70[degree], canopy reflectance was expressed as linear functions for each spectral band. These functions were used to calculate factors for reflectance standardization. Nomograms, containing reflectance correction factors for mature spruce stands, are presented. These can be directly applied in time-series analysis of multitemporal spectral data.

  18. Nursing students' reflections on racism.

    PubMed

    Schaefer, Karen Moore

    2008-01-01

    Racism is the systematic oppression of people of color at personal/interpersonal, institutional, and/or cultural levels. Discussions about racism often become emotional and personal. A discussion related to the accurate labeling of students on the basis of their heritage in an undergraduate professional issues class became emotionally charged. To prevent any further escalation of emotions, the author brought closure by asking students to read and write a reflective response to the Black Prayer. This article is a summary of urban nursing students' reflections and how giving voice to such reflections is a way of opening the door to frank discussions of racism and its effects.

  19. Plant canopy specular reflectance model

    NASA Technical Reports Server (NTRS)

    Vanderbilt, V. C.; Grant, L.

    1985-01-01

    A model is derived for the amount of light specularly reflected and polarized by a plant canopy. The model is based on the morphological and phenological characteristics of the canopy and upon the Fresnel equations of optics. The theory demonstrates that the specular reflectance of the plant canopy is a function of the angle of incidence and potentially contains information to help discriminate between species. The theory relates the specular reflectance to botanical condition of the canopy - to factors such as development stage, plant vigor, and leaf area index (LAI).

  20. Reflections from an International Immersion Trip: New Possibilities to Institutionalize Curriculum

    ERIC Educational Resources Information Center

    Rodriguez, Encarna

    2011-01-01

    One of the main challenges confronted by higher education in the 21st century is to internationalize its programs and to make students more globally competent. This challenge is not new, but it has become increasingly complex. Gutek (1993) explains how the efforts to internationalize the university in the United States became particularly…

  1. Citizenship Education Research in Varied Contexts: Reflections and Future Possibilities. A Review Essay

    ERIC Educational Resources Information Center

    Tudball, Libby

    2015-01-01

    Three books are the subject of this review essay: (1) Avril Keating's (2014) publication, "Education for Citizenship in Europe: European Policies, National Adaptations and Young People's Attitudes"; (2) "The Political Classroom: Evidence and Ethics in Democratic Education", Diana Hess and Paula McAvoy (2015); and (3) "We…

  2. A Time for Silence? Its Possibilities for Dialogue and for Reflective Learning

    ERIC Educational Resources Information Center

    Zimmermann, Ana Cristina; Morgan, W. John

    2016-01-01

    From the beginning of history sounds have played a fundamentally important role in humanity's development as ways of expression and of communication. However in contemporary western society, and indeed globally, we are experiencing an excess of speech and a relentless encouragement to expression. Such excess indicates a misunderstanding about what…

  3. Reflections on Focus Group Sessions Regarding Inclusive Education: Reconsidering Focus Group Research Possibilities

    ERIC Educational Resources Information Center

    Nel, Norma M.; Romm, Norma R. A.; Tlale, L. D. N.

    2015-01-01

    In this article we deliberate upon our way of facilitating focus group sessions with teachers concerning their views on inclusive education, by referring also to feedback that we received from the participants when they commented upon their experiences of the sessions. (The teacher participants were from three separate primary schools in South…

  4. The Possible Selves of Young Fathers in Prison

    ERIC Educational Resources Information Center

    Meek, Rosie

    2011-01-01

    Drawing on the social psychological concept of possible selves, this study explores the future self concept of young fathers in prison. In considering life after release from prison, qualitative data relating to hoped-for, feared and expected possible selves was generated by 34 young fathers aged between 18 and 21 years. The most common categories…

  5. Individual and age-related variation in chromatic contrast adaptation

    PubMed Central

    Elliott, Sarah L.; Werner, John S.; Webster, Michael A.

    2012-01-01

    Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected age-related changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18–22 years of age) and 15 older individuals (66–82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast

  6. [Strategies for successful ageing].

    PubMed

    Orozco Ríos, Adriana Martha; López Velarde Peña, Tatiana; Martínez Gallardo Prieto, Lorenza

    2016-01-01

    There has been an increase in the interest of anti-ageing medicine in the last few years, with a growth in the industry of products that promise to prolong life and restore all the suffering or "defects" produced by age. The understanding of ageing has changed over the years, giving rise to the possibility of intervening in different metabolic and cellular pathways, and thus, delaying the appearance of the degenerative chronic diseases that appear with age, and that are finally the causing factors of the vulnerability that leads to our death. It is hoped that we can help the clinician to orientate their patients, who, due to the overwhelming amount of information they receive by the Internet, arrive at the clinic full of questions, waiting to receive absolute answer from their physician in order to increase their longevity and quality of life. This article presents an analysis of the physical activity, diets, supplements and drugs that are being investigated as anti-ageing measures and of the many clinical studies that have produced encouraging, measurable and reproducible results.

  7. Immunity, ageing and cancer

    PubMed Central

    Derhovanessian, Evelyna; Solana, Rafael; Larbi, Anis; Pawelec, Graham

    2008-01-01

    Compromised immunity contributes to the decreased ability of the elderly to control infectious disease and to their generally poor response to vaccination. It is controversial as to how far this phenomenon contributes to the well-known age-associated increase in the occurrence of many cancers in the elderly. However, should the immune system be important in controlling cancer, for which there is a great deal of evidence, it is logical to propose that dysfunctional immunity in the elderly would contribute to compromised immunosurveillance and increased cancer occurrence. The chronological age at which immunosenescence becomes clinically important is known to be influenced by many factors, including the pathogen load to which individuals are exposed throughout life. It is proposed here that the cancer antigen load may have a similar effect on "immune exhaustion" and that pathogen load and tumor load may act additively to accelerate immunosenescence. Understanding how and why immune responsiveness changes in humans as they age is essential for developing strategies to prevent or restore dysregulated immunity and assure healthy longevity, clearly possible only if cancer is avoided. Here, we provide an overview of the impact of age on human immune competence, emphasizing T-cell-dependent adaptive immunity, which is the most sensitive to ageing. This knowledge will pave the way for rational interventions to maintain or restore appropriate immune function not only in the elderly but also in the cancer patient. PMID:18816370

  8. [Strategies for successful ageing].

    PubMed

    Orozco Ríos, Adriana Martha; López Velarde Peña, Tatiana; Martínez Gallardo Prieto, Lorenza

    2016-01-01

    There has been an increase in the interest of anti-ageing medicine in the last few years, with a growth in the industry of products that promise to prolong life and restore all the suffering or "defects" produced by age. The understanding of ageing has changed over the years, giving rise to the possibility of intervening in different metabolic and cellular pathways, and thus, delaying the appearance of the degenerative chronic diseases that appear with age, and that are finally the causing factors of the vulnerability that leads to our death. It is hoped that we can help the clinician to orientate their patients, who, due to the overwhelming amount of information they receive by the Internet, arrive at the clinic full of questions, waiting to receive absolute answer from their physician in order to increase their longevity and quality of life. This article presents an analysis of the physical activity, diets, supplements and drugs that are being investigated as anti-ageing measures and of the many clinical studies that have produced encouraging, measurable and reproducible results. PMID:26656211

  9. Age Distribution of Groundwater

    NASA Astrophysics Data System (ADS)

    Morgenstern, U.; Daughney, C. J.

    2012-04-01

    Groundwater at the discharge point comprises a mixture of water from different flow lines with different travel time and therefore has no discrete age but an age distribution. The age distribution can be assessed by measuring how a pulse shaped tracer moves through the groundwater system. Detection of the time delay and the dispersion of the peak in the groundwater compared to the tracer input reveals the mean residence time and the mixing parameter. Tritium from nuclear weapons testing in the early 1960s resulted in a peak-shaped tritium input to the whole hydrologic system on earth. Tritium is the ideal tracer for groundwater because it is an isotope of hydrogen and therefore is part of the water molecule. Tritium time series data that encompass the passage of the bomb tritium pulse through the groundwater system in all common hydrogeologic situations in New Zealand demonstrate a semi-systematic pattern between age distribution parameters and hydrologic situation. The data in general indicate high fraction of mixing, but in some cases also indicate high piston flow. We will show that still, 45 years after the peak of the bomb tritium, it is possible to assess accurately the parameters of age distributions by measuring the tail of the bomb tritium.

  10. Politics, Practices, and Possibilities of Open Educational Resources

    ERIC Educational Resources Information Center

    Phelan, Liam

    2012-01-01

    In this article, I reflect on the politics, practices and possibilities of the open educational resources (OER). OER raise important implications for current and potential students, for postsecondary education institutions, and for those currently teaching in higher education. The key questions raised by OER centre on the role of teaching in…

  11. Student Voice and Teacher Accountability: Possibilities and Problematics

    ERIC Educational Resources Information Center

    Keddie, Amanda

    2015-01-01

    The focus in this paper is on a student voice initiative at an English secondary school designed to improve the quality of teaching and learning. The initiative invites Year 8 students to train and work as "lesson observers" who provide feedback to teachers about their practice. The possibilities of this initiative to reflect a rich and…

  12. Reflection of cylindrical surface waves.

    PubMed

    Gordon, Reuven

    2009-10-12

    The reflection of the radially polarized surface wave on a metal wire at an abrupt end is derived. This theory allows for straightforward calculation of the reflection coefficient, including the phase and the amplitude, which will prove useful to the many applications in nanoplasmonics and terahertz spectroscopy. The theory shows excellent quantitative agreement with past comprehensive numerical simulations for small wires and for predicting the minima in reflection for larger wires. Using this theory, the wavelength dependent reflection is calculated for gold rods of diameter 10 nm, 26 nm and 85 nm, from which the Fabry-Perot resonance wavelengths are found. The Fabry-Perot resonances show good agreement with experimentally measured surface plasmon resonances in nanorods. This demonstrates the predictive ability of the theory for applications involving widely-used nanorods, optical antennas and plasmonic resonators. PMID:20372593

  13. Parental reflective functioning: an introduction.

    PubMed

    Slade, Arietta

    2005-09-01

    Reflective functioning refers to the essential human capacity to understand behavior in light of underlying mental states and intentions. The construct, introduced by Fonagy, Steele, Steele, Moran, and Higgitt in 1991, and elaborated by Fonagy and his colleagues over the course of the next decade, has had an enormous impact on developmental theory and clinical practice. This paper introduces the construct of parental reflective functioning, which refers to the parent's capacity to hold the child's mental states in mind, and begins with a review of Fonagy and his colleagues' essential ideas regarding the reflective function. Next, the applicability of this construct to parental representations of the child and the parent-child relationship is considered. A system for coding parental reflective functioning, which will serve as the organizing framework for this special issue, is described. Finally, the three papers that make up this special section are introduced.

  14. Reflections on wisdom and self.

    PubMed

    Samuel, Sophie

    2012-12-01

    The end of the year is often a time of reflection. For most of us, 2012 will have brought events that were planned, perhaps for years, as well as others that were full of serendipity or unexpected misfortune. We are invariably older than we were in January. We approach December with our own rituals: summer holidays, Hanukkah, Christmas or New Year's Eve. We may reflect on our joys and disappointments, or our actions and lessons learnt. PMID:23342382

  15. Reflections on wisdom and self.

    PubMed

    Samuel, Sophie

    2012-12-01

    The end of the year is often a time of reflection. For most of us, 2012 will have brought events that were planned, perhaps for years, as well as others that were full of serendipity or unexpected misfortune. We are invariably older than we were in January. We approach December with our own rituals: summer holidays, Hanukkah, Christmas or New Year's Eve. We may reflect on our joys and disappointments, or our actions and lessons learnt.

  16. Age-Related Changes in Predictive Capacity Versus Internal Model Adaptability: Electrophysiological Evidence that Individual Differences Outweigh Effects of Age.

    PubMed

    Bornkessel-Schlesewsky, Ina; Philipp, Markus; Alday, Phillip M; Kretzschmar, Franziska; Grewe, Tanja; Gumpert, Maike; Schumacher, Petra B; Schlesewsky, Matthias

    2015-01-01

    Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age-related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs) were measured in a group of older adults (60-81 years; n = 40) as they read sentences of the form "The opposite of black is white/yellow/nice." Replicating previous work in young adults, results showed a target-related P300 for the expected antonym ("white"; an effect assumed to reflect a prediction match), and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, "nice," versus the incongruous associated condition, "yellow"). These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that - at both a neurophysiological and a functional level - the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive performance. PMID

  17. Motherhood, Choice and the British Media: A Time to Reflect

    ERIC Educational Resources Information Center

    Hadfield, L.; Rudoe, N.; Sanderson-Mann, J.

    2007-01-01

    In this paper we ask: How is motherhood being represented in the British media, especially in relation to choice, age and fertility? Do media discourses reflect a redefinition or transformation of "motherhood" in the twenty-first century, and what implications do they have for feminist research into maternal identity and motherhood? As three Ph.D.…

  18. Reflections of a Lifelong Learner Teaching in Italy

    ERIC Educational Resources Information Center

    Kroth, Michael

    2014-01-01

    This article describes and summarizes the author's experience of teaching in Italy for three months and the impact it had on him and his learning. The author, at the age of 61, lived in Italy for three months and here he reflects on what he learned and how it relates to adult learning theory concepts.

  19. Body and Bulimia Revisited: Reflections on "A Secret Life"

    ERIC Educational Resources Information Center

    Tillmann, Lisa M.

    2009-01-01

    In 1996, the author published "A Secret Life in a Culture of Thinness: Reflections on Body, Food, and Bulimia" (Tillmann-Healy, 1996), an account of her struggle with binging and purging from ages 15 to 25. She came to understand bulimia as a communicative act, expressing fear, anxiety, and grief. From 25 to 35, her recovery from bulimia involved…

  20. A Reflective Conversation with Ugur Sak: Gifted Education in Turkey

    ERIC Educational Resources Information Center

    Shaughnessy, Michael F.; Sak, Ugur

    2015-01-01

    In this reflective conversation, Ugur Sak discusses the current "state of the art" of gifted education in Turkey. He reviews the use of enrichment, discusses acceleration and reviews curricular procedures in Turkey. He responds to questions about the identification of gifted students and discusses the age old debate of talent versus…

  1. Capacity Differences Reflected in the Recall Performance of Adults.

    ERIC Educational Resources Information Center

    Attig, Mary S.

    Recent theories in cognitive psychology have emphasized the role of capacity requirements in encoding tasks. To examine the notion that age-related differences in the recall performance reflect differences in cognitive capacity, 80 adults (40 undergraduates, and 40 senior citizens) recalled newspaper advertisements under free recall and cued…

  2. Experiments on Guderley Mach reflection

    NASA Astrophysics Data System (ADS)

    Skews, Beric William; Li, Gavin; Paton, Randall

    2009-06-01

    Experiments have been conducted in a large shock tube to examine the four-wave shock reflection pattern, now known as Guderley reflection (GR). The fourth wave, an expansion, is clearly identified, as is the supersonic patch behind the reflected wave. A shocklet terminating the supersonic patch behind the reflected wave is identified, which forms a second triple point further down the Mach stem. Evidence is presented showing the presence of more than one expansion wave and more than one shocklet, thus indicating the existence of more than one supersonic patch. In order to distinguish between cases with a single patch without the shocklet as originally proposed by Guderley and found in some computations, and the indications of a multi-patch geometry found here, and also in other computations, this latter case is designated Guderley Mach reflection (GMR). Multi-exposure images of the shock propagation superimposed on a single image frame enable estimates to be made of the strength of the major waves, and it is shown that the reflected wave is very weak.

  3. Reflections on intuition and expertise.

    PubMed

    Perry, M A

    2000-01-01

    Reflective practice now appears firmly established in the English speaking world of professional nursing practice and development. Outside this linguistic context, however, the concept seems less well-known. This paper describes an experience drawn from clinical practice and education in French-speaking Switzerland followed by explicit reflection grounded in questions generated by Johns' model for structured reflection. Thus, a concept well-described in the English-language literature underpins an innovative approach to a French-language clinical teaching situation. The professional implications of this situation are explored through meaningful reflection providing new insight into familiar circumstances as they relate to the nurse tutor's role. This exploration is followed by a critical approach to the experience and the subsequent structured reflection in order to address relationships between intuition and expertise and self-awareness through reflection. A hermeneutic perspective provides additional insight into the nurse-patient relationship where both come to the situation with their own 'pre-understandings'. Individual horizons thus endorse a new understanding going beyond taken-for-granted meanings.

  4. "Aging bull'.

    PubMed

    Geelhoed, G W

    1996-12-01

    An old bull, it is said by those who know, can have his troubles. Included among these are vertebral osteosclerosis and ankylosing spondylosis; this stiffening up limits, rather than accentuates, the value and reproductive potential of a stud bull past his prime. Associated with these abnormalities, however-and not seen in age-matched cows of comparable breeds-are fascinating endocrine neoplasms suggestive of a pattern that could be productive as a model of human hereditary endocrine abnormalities. Adjacent to the thyroid gland in other vertebrates are ultimobranchial bodies that are incorporated into the lateral thyroid lobes in primates as the parafollicular "C cells' of the thyroid. These are the cells in man that give rise to medullary thyroid cancer and are associated with calcitonin secretion, useful as a tumor marker. In aging bulls of whatever breed, nearly half exhibit abnormality of these ultimobranchial bodies: 20% show hyperplasia, and 30% have frank neoplasia. These ultimobranchial tumors appear in bulls passing 6 1/2 years in age, and are absent in young bulls and all cows of any age. Calcitonin can be demonstrated in the ultimobranchial tumors from bulls, and secretion is stimulated by calcium infusion, though serum calcium remains normal. The ultimobranchial tumors themselves can range from hyperplasia through adenoma to metastasizing carcinoma-in fact, representing one of the commoner cattle cancers. Parathyroid glands taken from bulls with these ultimobranchial tumors initially show evidence of inhibited secretory activity and morphologic atrophy, but later go on to develop hyperplasia and, eventually, autonomy. Cattle forage on calcium-rich diets. Bulls appear to respond to this calcium excess from the positive balance, but breeding cows have the unique calcium deficits of the high net loss of calcium through lactation and the large requirements of calcifying a fetal skeleton. Chronic stimulation of the APUD-derived ultimobranchial bodies by high

  5. Combined aging of beryllium bronze

    SciTech Connect

    Duraev, P.P.; Kaplun, Yu.A.; Pastukhova, Zh.P.; Rakhshtadt, A.G.

    1986-01-01

    This article evaluates the possibility of increasing the resistance of beryllium bronze to small plastic deformations as a result of the application of stepped aging under stress. Low-temperature aging under conditions of bending under a stress of about 100 MPa was applied to alloy BrBNT1, 9Mg at 150, 180, and 210 /sup 0/C, high-temperature aging at 300 and 340 /sup 0/C under stress and without stress. As a result of applying stepped aging under stress, the elastic limit of the alloy BrBNT1, 9Mg was raised to 900 MPa. Stepped aging under stress has a substantial effect on the relaxation stability of the alloy. The procedure suggested in the article for aging may be used efficiently for treating elastic elements made of other brands of bronze as well.

  6. Resonant diffraction of synchrotron radiation: New possibilities

    NASA Astrophysics Data System (ADS)

    Ovchinnikova, E. N.; Mukhamedzhanov, E. Kh.

    2016-09-01

    Resonant diffraction of synchrotron radiation (SR) is a modern method of studying the structure and properties of condensed matter that can be implemented on third-generation synchrotrons. This method allows one to investigate local properties of media (including magnetic and electronic ones) and observe thermal vibrations, defects, and orbital and charge orderings. A brief review of the advance provided by SR resonant diffraction is presented, and the capabilities of this method for analyzing phase transitions are considered in more detail by the example of potassium dihydrogen phosphate and rubidium dihydrogen phosphate crystals. It is shown that the investigation of the temperature dependence of forbidden reflections not only makes it possible to observe the transition from para- to ferroelectric phase, but also gives information about the proton distribution at hydrogen bonds.

  7. As Old as You Feel: Age Identity in Middle and Later Life.

    ERIC Educational Resources Information Center

    Logan, John R.; And Others

    1992-01-01

    Interviewed 1,200 adults aged 40 and older to study age identity (labels reflecting self-perception in terms of age) and its relationship to well-being. Chronological age, poor health, and widow or divorce status are associated with older age identity. Having children is related to middle-aged identity. (KS)

  8. Alpha-Synuclein Levels in Blood Plasma Decline with Healthy Aging

    PubMed Central

    Koehler, Niklas K. U.; Stransky, Elke; Meyer, Mirjam; Gaertner, Susanne; Shing, Mona; Schnaidt, Martina; Celej, Maria S.; Jovin, Thomas M.; Leyhe, Thomas; Laske, Christoph; Batra, Anil; Buchkremer, Gerhard; Fallgatter, Andreas J.; Wernet, Dorothee; Richartz-Salzburger, Elke

    2015-01-01

    There is unequivocal evidence that alpha-synuclein plays a pivotal pathophysiological role in neurodegenerative diseases, and in particular in synucleinopathies. These disorders present with a variable extent of cognitive impairment and alpha-synuclein is being explored as a biomarker in CSF, blood serum and plasma. Considering key events of aging that include proteostasis, alpha-synuclein may not only be useful as a marker for differential diagnosis but also for aging per se. To explore this hypothesis, we developed a highly specific ELISA to measure alpha-synuclein. In healthy males plasma alpha-synuclein levels correlated strongly with age, revealing much lower concentrations in older (avg. 58.1 years) compared to younger (avg. 27.6 years) individuals. This difference between the age groups was enhanced after acidification of the plasmas (p<0.0001), possibly reflecting a decrease of alpha-synuclein-antibody complexes or chaperone activity in older individuals. Our results support the concept that alpha-synuclein homeostasis may be impaired early on, possibly due to disturbance of the proteostasis network, a key component of healthy aging. Thus, alpha-synuclein may be a novel biomarker of aging, a factor that should be considered when analyzing its presence in biological specimens. PMID:25844871

  9. Well posedness and physical possibility

    NASA Astrophysics Data System (ADS)

    Gyenis, Balazs

    There is a sentiment shared among physicists that well posedness is a necessary condition for physical possibility. The arguments usually offered for well posedness have an epistemic flavor and thus they fall short of establishing the metaphysical claim that lack of well posedness implies physical impossibility. In this work we analyze the relationship of well posedness to prediction and confirmation as well as the notion of physical possibility and we devise three novel and independent argumentative strategies that may succeed where the usual epistemic arguments fail. Keywords: determinism, laws of nature, metaphysics, philosophy of physics, physical possibility, prediction, well posed problem.

  10. Seasonal Variations of Stratospheric Age Spectra in GEOSCCM

    NASA Technical Reports Server (NTRS)

    Li, Feng; Waugh, Darryn; Douglass, Anne R.; Newman, Paul A.; Pawson, Steven; Stolarski, Richard S.; Strahan, Susan E.; Nielsen, J. Eric

    2011-01-01

    There are many pathways for an air parcel to travel from the troposphere to the stratosphere, each of which takes different time. The distribution of all the possible transient times, i.e. the stratospheric age spectrum, contains important information on transport characteristics. However, it is computationally very expensive to compute seasonally varying age spectra, and previous studies have focused mainly on the annual mean properties of the age spectra. To date our knowledge of the seasonality of the stratospheric age spectra is very limited. In this study we investigate the seasonal variations of the stratospheric age spectra in the Goddard Earth Observing System Chemistry Climate Model (GEOSCCM). We introduce a method to significantly reduce the computational cost for calculating seasonally dependent age spectra. Our simulations show that stratospheric age spectra in GEOSCCM have strong seasonal cycles and the seasonal cycles change with latitude and height. In the lower stratosphere extratropics, the average transit times and the most probable transit times in the winter/early spring spectra are more than twice as old as those in the summer/early fall spectra. But the seasonal cycle in the subtropical lower stratosphere is nearly out of phase with that in the extratropics. In the middle and upper stratosphere, significant seasonal variations occur in the sUbtropics. The spectral shapes also show dramatic seasonal change, especially at high latitudes. These seasonal variations reflect the seasonal evolution of the slow Brewer-Dobson circulation (with timescale of years) and the fast isentropic mixing (with timescale of days to months).

  11. Reflections

    ERIC Educational Resources Information Center

    Bartell, Carol A.

    2015-01-01

    From 1998-2000, Carol Bartell served as President of the California Council on the Education of Teachers. However, election to office in this organization is generally a six-year commitment, because an individual will serve for two years as President Elect, two years as President, and two more as Past President. In this article, she expresses that…

  12. Reflections.

    ERIC Educational Resources Information Center

    Li Preti, Franca

    1994-01-01

    Discusses the promise and problems of conflict resolution programs operating in the schools. Argues that, with open channels of communication, ongoing evaluation, and student control, such programs can bring long-term benefits to schools and communities. (SR)

  13. Age Relationship

    NASA Technical Reports Server (NTRS)

    2006-01-01

    12 June 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a group of impact craters in Aonia Planum, Mars. Remarkably, two of the craters are approximately equal in size, however, they clearly differ in age. The left (west) crater has a well-defined rim and its ejecta blanket overlies part of the less pronounced crater to its immediate east. The one with the ejecta blanket is younger. Other circular depressions in this bouldery scene are also old, eroded impact craters.

    Location near: 59.5oS, 78.5oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Autumn

  14. DNA damage and ageing: new-age ideas for an age-old problem

    PubMed Central

    Garinis, George A.; van der Horst, Gijsbertus T. J.; Vijg, Jan; Hoeijmakers, Jan H. J.

    2015-01-01

    Loss of genome maintenance may causally contribute to ageing, as exemplified by the premature appearance of multiple symptoms of ageing in a growing family of human syndromes and in mice with genetic defects in genome maintenance pathways. Recent evidence revealed a similarity between such prematurely ageing mutants and long-lived mice harbouring mutations in growth signalling pathways. At first sight this seems paradoxical as they represent both extremes of ageing yet show a similar ‘survival’ response that is capable of delaying age-related pathology and extending lifespan. Understanding the mechanistic basis of this response and its connection with genome maintenance would open exciting possibilities for counteracting cancer or age-related diseases, and for promoting longevity. PMID:18978832

  15. Low reflectance radio frequency load

    DOEpatents

    Ives, R. Lawrence; Mizuhara, Yosuke M

    2014-04-01

    A load for traveling microwave energy has an absorptive volume defined by cylindrical body enclosed by a first end cap and a second end cap. The first end cap has an aperture for the passage of an input waveguide with a rotating part that is coupled to a reflective mirror. The inner surfaces of the absorptive volume consist of a resistive material or are coated with a coating which absorbs a fraction of incident RF energy, and the remainder of the RF energy reflects. The angle of the reflector and end caps is selected such that reflected RF energy dissipates an increasing percentage of the remaining RF energy at each reflection, and the reflected RF energy which returns to the rotating mirror is directed to the back surface of the rotating reflector, and is not coupled to the input waveguide. Additionally, the reflector may have a surface which generates a more uniform power distribution function axially and laterally, to increase the power handling capability of the RF load. The input waveguide may be corrugated for HE11 mode input energy.

  16. Reflectance spectra of subarctic lichens

    NASA Technical Reports Server (NTRS)

    Petzold, Donald E.; Goward, Samuel N.

    1988-01-01

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the midlatitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 microns, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future.

  17. Asteroid family ages

    NASA Astrophysics Data System (ADS)

    Spoto, Federica; Milani, Andrea; Knežević, Zoran

    2015-09-01

    A new family classification, based on a catalog of proper elements with ∼384,000 numbered asteroids and on new methods is available. For the 45 dynamical families with >250 members identified in this classification, we present an attempt to obtain statistically significant ages: we succeeded in computing ages for 37 collisional families. We used a rigorous method, including a least squares fit of the two sides of a V-shape plot in the proper semimajor axis, inverse diameter plane to determine the corresponding slopes, an advanced error model for the uncertainties of asteroid diameters, an iterative outlier rejection scheme and quality control. The best available Yarkovsky measurement was used to estimate a calibration of the Yarkovsky effect for each family. The results are presented separately for the families originated in fragmentation or cratering events, for the young, compact families and for the truncated, one-sided families. For all the computed ages the corresponding uncertainties are provided, and the results are discussed and compared with the literature. The ages of several families have been estimated for the first time, in other cases the accuracy has been improved. We have been quite successful in computing ages for old families, we have significant results for both young and ancient, while we have little, if any, evidence for primordial families. We found 2 cases where two separate dynamical families form together a single V-shape with compatible slopes, thus indicating a single collisional event. We have also found 3 examples of dynamical families containing multiple collisional families, plus a dubious case: for these we have obtained discordant slopes for the two sides of the V-shape, resulting in distinct ages. We have found 2 cases of families containing a conspicuous subfamily, such that it is possible to measure the slope of a distinct V-shape, thus the age of the secondary collision. We also provide data on the central gaps appearing in

  18. Value of Reflected Light Microscopy in Teaching.

    ERIC Educational Resources Information Center

    Pasteris, Jill Dill

    1983-01-01

    Briefly reviews some optical and other physical properties of minerals that can be determined in reflected/incident light. Topics include optical properties of minerals, reflectance, internal reflections, color, bireflectance and reflection pleochroism, anisotropism, zonation, and reflected light microscopy as a teaching tool in undergraduate…

  19. Closeness Possible through Computer Networking.

    ERIC Educational Resources Information Center

    Dodd, Julie E.

    1989-01-01

    Points out the benefits of computer networking for scholastic journalism. Discusses three systems currently offering networking possibilities for publications: the Student Press Information Network; the Youth Communication Service; and the Dow Jones Newspaper Fund's electronic mail system. (MS)

  20. Is extinction age dependent?

    USGS Publications Warehouse

    Doran, N.A.; Arnold, A.J.; Parker, W.C.; Huffer, F.W.

    2006-01-01

    Age-dependent extinction is an observation with important biological implications. Van Valen's Red Queen hypothesis triggered three decades of research testing its primary implication: that age is independent of extinction. In contrast to this, later studies with species-level data have indicated the possible presence of age dependence. Since the formulation of the Red Queen hypothesis, more powerful tests of survivorship models have been developed. This is the first report of the application of the Cox Proportional Hazards model to paleontological data. Planktonic foraminiferal morphospecies allow the taxonomic and precise stratigraphic resolution necessary for the Cox model. As a whole, planktonic foraminiferal morphospecies clearly show age-dependent extinction. In particular, the effect is attributable to the presence of shorter-ranged species (range < 4 myr) following extinction events. These shorter-ranged species also possess tests with unique morphological architecture. The morphological differences are probably epiphenomena of underlying developmental and heterochronic processes of shorter-ranged species that survived various extinction events. Extinction survivors carry developmental and morphological characteristics into postextinction recovery times, and this sets them apart from species populations established independently of extinction events. Copyright ?? 2006, SEPM (Society for Sedimentary Geology).