Dinetah: An Early History of the Navajo People.

ERIC Educational Resources Information Center

Sundberg, Lawrence D.

Originally written for Navajo elementary school students, this book chronicles the history of the Navajo people from prehistory to 1868. The book presents a sympathetic history of a people who depended on their tenacity and creative adaptability to survive troubled times. Chapters examine how Navajo culture changed from that of an early hunting…

Early management in children with burns: Cooling, wound care and pain management.

PubMed

Baartmans, M G A; de Jong, A E E; van Baar, M E; Beerthuizen, G I J M; van Loey, N E E; Tibboel, D; Nieuwenhuis, M K

2016-06-01

Early management in burns, i.e. prior to admission in a burn center, is essential for an optimal process and outcome of burn care. Several publications have reported suboptimal early management, including low levels of pain medication after trauma, especially in children. The aim of this study was to evaluate the current practice in the Netherlands and factors related to early management in pediatric burns, i.e. cooling, wound covering and pain management. To study possible change and improvement over time, two study periods were compared. This study involved two periods; January 2002-March 2004 (period 1) and January 2007-August 2008 (period 2). All children (0-15 years of age) with acute burns admitted within 24h after burn to one of the three Dutch Burn centers with a formal referral were eligible. Data were obtained from patient records, both retrospectively and prospectively. A total of 323 and 299 children were included in periods 1 and 2, respectively. The vast majority of children in both study periods had been cooled before admission (>90%). Over time, wound covering increased significantly (from 64% to 89%) as well as pain treatment (from 68% to 79%). Predominantly paracetamol and morphine were used. Referral from ambulance services (OR=41.4, 95%CI=16.6-103.0) or general practitioners (OR=59.7, 95%CI=25.1-141.8) were strong independent predictors for not receiving pre-burn center pain medication. On the other hand, flame burns (OR=0.2, 95%CI=0.1-0.5) and more extensive burns (TBSA 5-10%: OR=0.4, 95%CI=-0.2 to 0.8; TBSA≥10%: OR=0.2, 95%CI=0.1-0.4) were independent predictors of receiving pain medication. Referring physicians of children with burns were overall well informed: they cool the wound after burns and cover it before transport to prevent hypothermia and reduce the pain. Additional studies should be conducted to clarify the duration and temperature for cooling to be effective. Furthermore, there is room and a need for improvement regarding early

History Dependence of the Microstructure on Time-Dependent Deformation During In-Situ Cooling of a Nickel-Based Single-Crystal Superalloy

NASA Astrophysics Data System (ADS)

Panwisawas, Chinnapat; D'Souza, Neil; Collins, David M.; Bhowmik, Ayan; Roebuck, Bryan

2018-05-01

Time-dependent plastic deformation through stress relaxation and creep deformation during in-situ cooling of the as-cast single-crystal superalloy CMSX-4® has been studied via neutron diffraction, transmission electron microscopy, electro-thermal miniature testing, and analytical modeling across two temperature regimes. Between 1000 °C and 900 °C, stress relaxation prevails and gives rise to softening as evidenced by a decreased dislocation density and the presence of long segment stacking faults in γ phase. Lattice strains decrease in both the γ matrix and γ' precipitate phases. A constitutive viscoplastic law derived from in-situ isothermal relaxation test under-estimates the equivalent plastic strain in the prediction of the stress and strain evolution during cooling in this case. It is thereby shown that the history dependence of the microstructure needs to be taken into account while deriving a constitutive law and which becomes even more relevant at high temperatures approaching the solvus. Higher temperature cooling experiments have also been carried out between 1300 °C and 1150 °C to measure the evolution of stress and plastic strain close to the γ' solvus temperature. In-situ cooling of samples using ETMT shows that creep dominates during high-temperature deformation between 1300 °C and 1220 °C, but below a threshold temperature, typically 1220 °C work hardening begins to prevail from increasing γ' fraction and resulting in a rapid increase in stress. The history dependence of prior accumulated deformation is also confirmed in the flow stress measurements using a single sample while cooling. The saturation stresses in the flow stress experiments show very good agreement with the stresses measured in the cooling experiments when viscoplastic deformation is dominant. This study demonstrates that experimentation during high-temperature deformation as well as the history dependence of the microstructure during cooling plays a key role in deriving

Method for early detection of cooling-loss events

DOEpatents

Bermudez, Sergio A.; Hamann, Hendrik; Marianno, Fernando J.

2015-06-30

A method of detecting cooling-loss event early is provided. The method includes defining a relative humidity limit and change threshold for a given space, measuring relative humidity in the given space, determining, with a processing unit, whether the measured relative humidity is within the defined relative humidity limit, generating a warning in an event the measured relative humidity is outside the defined relative humidity limit and determining whether a change in the measured relative humidity is less than the defined change threshold for the given space and generating an alarm in an event the change is greater than the defined change threshold.

Method for early detection of cooling-loss events

DOEpatents

Bermudez, Sergio A.; Hamann, Hendrik F.; Marianno, Fernando J.

2015-12-22

A method of detecting cooling-loss event early is provided. The method includes defining a relative humidity limit and change threshold for a given space, measuring relative humidity in the given space, determining, with a processing unit, whether the measured relative humidity is within the defined relative humidity limit, generating a warning in an event the measured relative humidity is outside the defined relative humidity limit and determining whether a change in the measured relative humidity is less than the defined change threshold for the given space and generating an alarm in an event the change is greater than the defined change threshold.

Modeling Cooling Rates of Martian Flood Basalt Columns

NASA Astrophysics Data System (ADS)

Weiss, D. K.; Jackson, B.; Milazzo, M. P.; Barnes, J. W.

2011-12-01

Columnar jointing in large basalt flows have been extensively studied and can provide important clues about the emplacement conditions and cooling history of a basalt flow. The recent discovery of basalt columns on Mars in crater walls near Marte Vallis provides an opportunity to infer conditions on early Mars when the Martian basalt flows were laid down. Comparison of the Martian columns to Earth analogs allows us to gain further insight into the early Martian climate, and among the best terrestrial analogs are the basalt columns in the Columbia River Basalt Group (CRBG) in eastern Washington. The CRBG is one of the youngest (< 17 Myrs old) and most extensively studied basalt provinces in the world, extending over 163,700 square km with total thickness exceeding 1 km in some places. The morphologies and textures of CRBG basalt columns suggest that in many places flows ~100 m thick cooled at uniform rates, even deep in the flow interior. Such cooling seems to require the presence of water in the column joints since the flow interiors should have cooled much more slowly than the flow margins if conductive cooling dominated. Secondary features, such pillow basalts, likewise suggest the basalt flows were in direct contact with standing water in many places. At the resolution provided by the orbiting HiRISE camera (0.9 m), the Martian basalt columns resemble the CRBG columns in many respects, and so, subject to important caveats, inferences linking the morphologies of the CRBG columns to their thermal histories can be extended in some respects to the Martian columns. In this presentation, we will describe our analysis of the HiRISE images of the Martian columns and what can be reasonably inferred about their thermal histories and the conditions under which they were emplaced. We will also report on a field expedition to the CRBG in eastern Washington State. During that expedition, we surveyed basalt column outcrops on the ground and from the air using Unmanned Aerial

Impact Constraints on Major Events in Early Mars History

NASA Technical Reports Server (NTRS)

Frey, H. V.

2004-01-01

MOLA data have revealed a large population of "Quasi-Circular Depressions" (QCDs) with little or no visible expression in image data. These likely buried impact basins have important implications for the age of the lowland crust, how that compares with original highland crust, and when and how the crustal dichotomy may have formed. The buried lowlands are of Early Noachian age, likely slightly younger than the buried highlands but older than the exposed (visible) highland surface. A depopulation of large visible basins at diameters 800 to 1300 km suggests some global scale event early in martian history, maybe related to the formation of the lowlands and/or the development of Tharsis. A suggested early disappearance of the global magnetic field can be placed within a temporal sequence of formation of the very largest impact basins. The global field appears to have disappeared at about the time the lowlands formed. It seems likely the topographic crustal dichotomy was produced very early in martian history by processes which operated very quickly. Thus there appears to have been a northern lowland throughout nearly all of martian history, predating the last of the really large impacts (Hellas, Argyre and Isidis) and their likely very significant environmental consequences.

Early developments in solar cooling equipment

NASA Technical Reports Server (NTRS)

Price, J. M.

1978-01-01

A brief description of a development program to design, fabricate and field test a series of solar operated or driven cooling devices, undertaken by the Marshall Space Flight Center in the context of the Solar Heating and Cooling Demonstration Act of 1974, is presented. Attention is given to two basic design concepts: the Rankine cycle principle and the use of a dessicant for cooling.

Early history of scapular fractures.

PubMed

Bartoníček, Jan; Kozánek, Michal; Jupiter, Jesse B

2016-01-01

The first to use the term Scapula was Vesalius (1514-1564) and thus it has remained ever since. Probably the oldest injured scapula, from 250 million years ago, was described by Chinese authors of a skeletal examination of a fossilised remains of a dinosaur Yangchuanosaurus hepingensis. In humans, the oldest known scapular fractures date back to the prehistoric and early historic times. In ancient times, a fracture of acromion was described in the treatises of Hippocrates. Early modern history of the treatment of scapular fractures is closely interlinked with the history of the French surgery. The first to point out the existence of these fractures were Petit, Du Verney and Desault in the 18th century. The first study devoted solely to scapular fractures was published by Traugott Karl August Vogt in 1799. Thomas Callaway published in 1849 an extensive dissertation on injuries to the shoulder girdle, in which he discussed a number of cases known at that time. The first radiograph of a scapular fracture was published by Petty in 1907. Mayo Robson (1884), Lambotte (1913) and Lane (1914) were pioneers in the surgical treatment of these fractures, followed in 1923 by the French surgeons Lenormat, Dujarrier and Basset. The first internal fixation of the glenoid fossa, including a radiograph, was published by Fischer in 1939.

Jurassic cooling ages in Paleozoic to early Mesozoic granitoids of northeastern Patagonia: 40Ar/39Ar, 40K-40Ar mica and U-Pb zircon evidence

NASA Astrophysics Data System (ADS)

Martínez Dopico, Carmen I.; Tohver, Eric; López de Luchi, Mónica G.; Wemmer, Klaus; Rapalini, Augusto E.; Cawood, Peter A.

2017-10-01

U-Pb SHRIMP zircon crystallization ages and Ar-Ar and K-Ar mica cooling ages for basement rocks of the Yaminué and Nahuel Niyeu areas in northeastern Patagonia are presented. Granitoids that cover the time span from Ordovician to Early Triassic constitute the main outcrops of the western sector of the Yaminué block. The southern Yaminué Metaigneous Complex comprises highly deformed Ordovician and Permian granitoids crosscut by undeformed leucogranite dikes (U-Pb SHRIMP zircon age of 254 ± 2 Ma). Mica separates from highly deformed granitoids from the southern sector yielded an Ar-Ar muscovite age of 182 ± 3 Ma and a K-Ar biotite age of 186 ± 2 Ma. Moderately to highly deformed Permian to Early Triassic granitoids made up the northern Yaminué Complex. The Late Permian to Early Triassic (U-Pb SHRIMP zircon age of 252 ± 6 Ma) Cabeza de Vaca Granite of the Yaminué block yielded Jurassic mica K-Ar cooling ages (198 ± 2, 191 ± 1, and 190 ± 2 Ma). At the boundary between the Yaminué and Nahuel Niyeu blocks, K-Ar muscovite ages of 188 ± 3 and 193 ± 5 Ma were calculated for the Flores Granite, whereas the Early Permian Navarrete granodiorite, located in the Nahuel Niyeu block, yielded a K-Ar biotite age of 274 ± 4 Ma. The Jurassic thermal history is not regionally uniform. In the supracrustal exposures of the Nahuel Niyeu block, the Early Permian granitoids of its western sector as well as other Permian plutons and Ordovician leucogranites located further east show no evidence of cooling age reset since mica ages suggest cooling in the wake of crystallization of these intrusive rocks. In contrast, deeper crustal levels are inferred for Permian-Early Triassic granitoids in the Yaminué block since cooling ages for these rocks are of Jurassic age (198-182 Ma). Jurassic resetting is contemporaneous with the massive Lower Jurassic Flores Granite, and the Marifil and Chon Aike volcanic provinces. This intraplate deformational pulse that affected northeastern

Learning Early Twentieth-Century History through First-Person Interviews

ERIC Educational Resources Information Center

Lark, Lisa A.

2007-01-01

For many of the students in the author's American history class, early twentieth-century American history seems far removed from their daily lives. Being first and second-generation American citizens, many of the students do not have the luxury of hearing grandparents and great-grandparents telling stories about FDR and Henry Ford. More…

Assembling the dodo in early modern natural history.

PubMed

Lawrence, Natalie

2015-09-01

This paper explores the assimilation of the flightless dodo into early modern natural history. The dodo was first described by Dutch sailors landing on Mauritius in 1598, and became extinct in the 1680s or 1690s. Despite this brief period of encounter, the bird was a popular subject in natural-history works and a range of other genres. The dodo will be used here as a counterexample to the historical narratives of taxonomic crisis and abrupt shifts in natural history caused by exotic creatures coming to Europe. Though this bird had a bizarre form, early modern naturalists integrated the dodo and other flightless birds through several levels of conceptual categorization, including the geographical, morphological and symbolic. Naturalists such as Charles L'Ecluse produced a set of typical descriptive tropes that helped make up the European dodo. These long-lived images were used for a variety of symbolic purposes, demonstrated by the depiction of the Dutch East India enterprise in Willem Piso's 1658 publication. The case of the dodo shows that, far from there being a dramatic shift away from emblematics in the seventeenth century, the implicit symbolic roles attributed to exotic beasts by naturalists constructing them from scant information and specimens remained integral to natural history.

Reversal of Fortune: Increased Star Formation Efficiencies in the Early Histories of Dwarf Galaxies?

NASA Astrophysics Data System (ADS)

Madau, Piero; Weisz, Daniel R.; Conroy, Charlie

2014-08-01

On dwarf galaxy scales, the different shapes of the galaxy stellar mass function and the dark halo mass function require a star-formation efficiency (SFE) in these systems that is currently more than 1 dex lower than that of Milky Way-size halos. Here, we argue that this trend may actually be reversed at high redshift. Specifically, by combining the resolved star-formation histories of nearby isolated dwarfs with the simulated mass-growth rates of dark matter halos, we show that the assembly of these systems occurs in two phases: (1) an early, fast halo accretion phase with a rapidly deepening potential well, characterized by a high SFE; and (2) a late, slow halo accretion phase where, perhaps as a consequence of reionization, the SFE is low. Nearby dwarfs have more old stars than predicted by assuming a constant or decreasing SFE with redshift, a behavior that appears to deviate qualitatively from the trends seen among more massive systems. Taken at face value, the data suggest that at sufficiently early epochs, dwarf galaxy halos above the atomic cooling mass limit can be among the most efficient sites of star formation in the universe.

Asperger's syndrome and autism: comparison of early history and outcome.

PubMed

Szatmari, P; Bartolucci, G; Bremner, R

1989-12-01

The authors compared children with Asperger syndrome (AS) with high-functioning autistic children and psychiatric outpatient controls on measures of early history and outcome. In terms of their early history, the autistic probands showed more social impairment, a higher frequency of echolalia and pronoun reversal, and a more restricted range of activities than the AS group. Cluster analysis suggested refinements to the diagnostic criteria, which resulted in larger differences between the groups on these early history measures. In terms of their outcome, the autistic probands spent more time in special education classes but developed fewer accessory psychiatric symptoms than the AS children. It was clear, however, that there were no substantive, qualitative differences between the AS and autistic groups, indicating that AS should be considered a mild form of high-functioning autism. The inclusion of AS among the autistic spectrum of disorders has implications both for aetiological studies and for prevalence estimates of the pervasive developmental disorders.

Increased Pre- and Early-Adolescent Stress in Youth with a Family History of Substance Use Disorder and Early Substance Use Initiation.

PubMed

Charles, Nora E; Mathias, Charles W; Acheson, Ashley; Bray, Bethany C; Ryan, Stacy R; Lake, Sarah L; Liang, Yuanyuan; Dougherty, Donald M

2015-10-01

Individuals with a family history of substance use disorders (Family History Positive) are more likely to have early-onset substance use (i.e., prior to age 15), which may contribute to their higher rates of substance use disorders. One factor that may differentiate Family History Positive youth who engage in early-onset substance use from other Family History Positive youth is exposure to stressors. The aim of this study was to quantify how exposure to stressors from age 11-15 varies as a function of family history of substance use disorders and early-onset substance use. Self-reported stressors were prospectively compared in a sample of predominately (78.9%) Hispanic youth that included 68 Family History Positive youth (50% female) who initiated substance use by age 15 and demographically matched non-users with (n = 136; 52.9% female) and without (n = 75; 54.7% female) family histories of substance use disorders. Stressors were assessed at 6-month intervals for up to 4 years. Both the severity of stressors and the degree to which stressors were caused by an individual's own behavior were evaluated. All three groups differed from one another in overall exposure to stressors and rates of increase in stressors over time, with Family History Positive youth who engaged in early-onset substance use reporting the greatest exposure to stressors. Group differences were more pronounced for stressors caused by the participants' behavior. Family History Positive users had higher cumulative severity of stressors of this type, both overall and across time. These results indicate greater exposure to stressors among Family History Positive youth with early-onset substance use, and suggest that higher rates of behavior-dependent stressors may be particularly related to early-onset use.

Increased Pre- and Early-Adolescent Stress in Youth with a Family History of Substance Use Disorder and Early Substance Use Initiation

PubMed Central

Charles, Nora E.; Mathias, Charles W.; Acheson, Ashley; Bray, Bethany C.; Ryan, Stacy R.; Lake, Sarah L.; Liang, Yuanyuan; Dougherty, Donald M.

2015-01-01

Individuals with a family history of substance use disorders (Family History Positive) are more likely to have early-onset substance use (i.e., prior to age 15), which may contribute to their higher rates of substance use disorders. One factor that may differentiate Family History Positive youth who engage in early-onset substance use from other Family History Positive youth is exposure to stressors. The aim of this study was to quantify how exposure to stressors from age 11 to 15 varies as a function of family history of substance use disorders and early-onset substance use. Self-reported stressors were prospectively compared in a sample of predominately (78.9%) Hispanic youth that included 68 Family History Positive youth (50% female) who initiated substance use by age 15 and demographically matched non-users with (n=136; 52.9% female) and without (n=75; 54.7% female) family histories of substance use disorders. Stressors were assessed at 6-month intervals for up to 4 years. Both the severity of stressors and the degree to which stressors were caused by an individual’s own behavior were evaluated. All three groups differed from one another in overall exposure to stressors and rates of increase in stressors over time, with Family History Positive youth who engaged in early-onset substance use reporting the greatest exposure to stressors. Group differences were more pronounced for stressors caused by the participants’ behavior. Family History Positive users had higher cumulative severity of stressors of this type, both overall and across time. These results indicate greater exposure to stressors among Family History Positive youth with early-onset substance use, and suggest that higher rates of behavior-dependent stressors may be particularly related to early-onset use. PMID:25788123

Early Childhood Education: History, Theory, and Practice. Second Edition

ERIC Educational Resources Information Center

Morgan, Harry

2010-01-01

Harry Morgan lays the foundations of what early childhood education is by integrating the history of the field with the philosophy and theories behind this discipline. From birth to age eight, when children become integrated into society through their education at school and at home, "Early Childhood Education" examines the education of this age…

The Littlest Historians: Early Years Programming in History Museums

ERIC Educational Resources Information Center

Leftwich, Mariruth; Haywood, Clare

2016-01-01

Working with children under five years old and the adults that accompany them is a rapidly growing area within the museum and wider cultural sector, with important emphasis being placed on early learning in both the United Kingdom and United States. For history museums in particular, early learning offers a unique set of questions and challenges,…

The Early History of Psychoanalysis in San Francisco.

PubMed

Benveniste, Daniel

2006-01-01

The early history of psychoanalysis in San Francisco begins in 1918 and ends in 1953. During those 35 years the San Francisco Bay Area witnessed the awakening of interest in psychoanalysis, the arrival of the European émigré analysts and the emergence of individuals and groups engaging in extraordinarily creative work and doing so in an ecumenical spirit and with a social commitment. This article provides an overview of this illustrious history and the people who participated in it.

Music as therapy in early history.

PubMed

Thaut, Michael H

2015-01-01

The notion of music as therapy is based on ancient cross-cultural beliefs that music can have a "healing" effect on mind and body. Explanations for the therapeutic mechanisms in music have almost always included cultural and social science-based causalities about the uses and functions of music in society. However, it is also important to note that the view of music as "therapy" was also always strongly influenced by the view and understanding of the concepts and causes of disease. Magical/mystical concepts of illness and "rational" medicine probably lived side by side for thousands of years. Not until the late-nineteenth and early-twentieth centuries were the scientific foundations of medicine established, which allowed the foundations of music in therapy to progress from no science to soft science and most recently to actual brain science. Evidence for "early music therapy" will be discussed in four broad historical-cultural divisions: preliterate cultures; early civilizations in Mesopotamia, Egypt, Israel; Greek Antiquity; Middle Ages, Renaissance, and Baroque. In reviewing "early music therapy" practice, from mostly unknown periods of early history (using preliterate cultures as a window) to increasingly better documented times, including preserved notation samples of actual "healing" music, five theories and applications of early music therapy can be differentiated. © 2015 Elsevier B.V. All rights reserved.

Acceleration of Cooling of Ice Giants by Condensation in Early Atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurosaki, Kenji; Ikoma, Masahiro, E-mail: kurosaki.k@nagoya-u.jp, E-mail: ikoma@eps.s.u-tokyo.ac.jp

The present infrared brightness of a planet originates partly from the accretion energy that the planet gained during its formation and hence provides important constraints to the planet formation process. A planet cools down from a hot initial state to the present state by losing energy through radiative emission from its atmosphere. Thus, the atmospheric properties affect the planetary cooling rate. Previous theories of giant planet cooling assume that the atmospheric composition is unchanged throughout the evolution. Planet formation theories, however, suggest that the atmospheres especially of ice giants are rich in heavy elements in the early stages. These heavy elementsmore » include condensable species such as H{sub 2}O, NH{sub 3}, and CH{sub 4}, which are expected to have a great impact on atmospheric temperature and thus on radiative emission through latent heat release. In this study we investigate the effect of such condensation on the planetary emission flux and quantify the impact on the cooling timescale. We then demonstrate that the latent heat of these species keeps the atmosphere hot and thus the emission flux high for billions of years, resulting in an acceleration of the cooling of ice giants. This sheds light on the long-standing problem that Uranus is much less bright than theoretically predicted and is different in brightness from Neptune in spite of the similarity in mass and radius. We also find that young ice giants with highly enriched atmospheres are much brighter in the mid-infrared than ice giants with non-enriched atmospheres. This provides important implications for future direct imaging of extrasolar ice giants.« less

Analysis of Mass Profiles and Cooling Flows of Bright, Early-Type Galaxies AO2, AO3 and Surface Brightness Profiles and Energetics of Intracluster Gas in Cool Galaxy Clusters AO3

NASA Technical Reports Server (NTRS)

White, Raymond E., III

1998-01-01

This final report uses ROSAT observations to analyze two different studies. These studies are: Analysis of Mass Profiles and Cooling Flows of Bright, Early-Type Galaxies; and Surface Brightness Profiles and Energetics of Intracluster Gas in Cool Galaxy Clusters.

Residual brain injury after early discontinuation of cooling therapy in mild neonatal encephalopathy.

PubMed

Lally, Peter J; Montaldo, Paolo; Oliveira, Vânia; Swamy, Ravi Shankar; Soe, Aung; Shankaran, Seetha; Thayyil, Sudhin

2018-07-01

We examined the brain injury and neurodevelopmental outcomes in a prospective cohort of 10 babies with mild encephalopathy who had early cessation of cooling therapy. All babies had MRI and spectroscopy within 2 weeks after birth and neurodevelopmental assessment at 2 years. Cooling was prematurely discontinued at a median age of 9 hours (IQR 5-13) due to rapid clinical improvement. Five (50%) had injury on MRI or spectroscopy, and two (20%) had an abnormal neurodevelopmental outcome at 2 years. Premature cessation of cooling therapy in babies with mild neonatal encephalopathy does not exclude residual brain injury and adverse long-term neurodevelopmental outcomes. This study refers to babies recruited into the MARBLE study (NCT01309711, pre-results stage). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Post-recombination early Universe cooling by translation-internal inter-conversion: The role of minor constituents.

PubMed

McCaffery, Anthony J

2015-09-14

Little is known of the mechanism by which H and H2, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H2, as Δj = - 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H2 in a H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H2 + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.

Post-recombination early Universe cooling by translation–internal inter-conversion: The role of minor constituents

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCaffery, Anthony J., E-mail: A.J.McCaffery@sussex.ac.uk

Little is known of the mechanism by which H and H{sub 2}, the principal constituents of the post-re-combination early Universe, cooled sufficiently to permit cluster formation, nucleosynthesis, and, eventually, the formation of structured objects. Radiative decay primarily cools the internal modes of H{sub 2}, as Δj = − 2 jumps accompany quadrupolar emission. This, however, would be a self-limiting mechanism. In this work, a translational energy cooling mechanism based on collision-induced, translation-to-internal mode conversion, is extended, following an earlier study [A. J. McCaffery and R. J. Marsh, J. Chem. Phys. 139, 234310 (2013)] of ensembles comprising H{sub 2} in amore » H atom bath gas. Here, the possible influence of minor species, such as HD, on this cooling mechanism is investigated. Results suggest that the influence of HD is small but not insignificant. Conversion is very rapid and an overall translation-to-internal energy conversion efficiency of some 5% could be expected. This finding may be of use in the further development of models of this complex phase of early Universe evolution. An unexpected finding in this study was that H{sub 2} + HD ensembles are capable of very rapid translation-to-internal conversion with efficiencies of >40% and relaxation rates that appear to be relatively slow. This may have potential as an energy storage mechanism.« less

Reliability of Early Magnetic Resonance Imaging (MRI) and Necessity of Repeating MRI in Noncooled and Cooled Infants With Neonatal Encephalopathy.

PubMed

Chakkarapani, Elavazhagan; Poskitt, Kenneth J; Miller, Steven P; Zwicker, Jill G; Xu, Qi; Wong, Darren S T; Roland, Elke H; Hill, Alan; Chau, Vann

2016-04-01

In cooled newborns with encephalopathy, although late magnetic resonance imaging (MRI) scan (10-14 days of age) is reliable in predicting long-term outcome, it is unknown whether early scan (3-6 days of life) is. We compared the predominant pattern and extent of lesion between early and late MRI in 89 term neonates with neonatal encephalopathy. Forty-three neonates (48%) were cooled. The predominant pattern of lesions and the extent of lesion in the watershed region agreed near perfectly in noncooled (kappa = 0.94; k = 0.88) and cooled (k = 0.89; k = 0.87) infants respectively. There was perfect agreement in the extent of lesion in the basal nuclei in noncooled infants (k = 0.83) and excellent agreement in cooled infants (k = 0.67). Changes in extent of lesions on late MRI occurred in 19 of 89 infants, with higher risk in infants with hypoglycemia and moderate-severe lesions in basal nuclei. In most term neonates with neonatal encephalopathy, early MRI (relative to late scan) robustly predicts the predominant pattern and extent of injury. © The Author(s) 2015.

Long-term subsidence, cooling, and exhumation history along the South Atlantic passive continental margin in NW-Namibia

NASA Astrophysics Data System (ADS)

Menges, Daniel; Glasmacher, Ulrich Anton; Salomon, Eric; Hackspacher, Peter Christian; Schneider, Gabi

2016-04-01

In northwest Namibia the Kaoko Belt is one of the most important Precambrian crustal segments that have stored the subsidence, cooling, and exhumation history of Namibia since the Neoproterozoic. ZFT-ages are processed to give new insights on this early evolution. Paleozoic to Mesozoic sedimentary rocks of the Karoo Supergroup and the Lower Cretaceous volcanic rocks of the Etendeka sequence overlay the Proterozoic metamorphic and intrusive rocks (1). New apatite fission-track (AFT) ages range from 390.9 (17.9) Ma to 80.8 (6.0) Ma. Along the coast apatites of Proterozoic rock samples reveal the youngest ages. Further inland the ages increase significantly. In addition, rapid change of AFT-ages occurs on both sides of major thrust and shear zones. Using the oldest thermochronological data the revealed t-T paths indicate a long era of exhumation, starting at the end of the Pan-African Orogeny in the Neoproterozoic and continuing into the Permo-Carboniferous. The subsequent sedimentation of the Karoo Supergroup initiates a new era of subsidence until the end of Triassic (2). The subsequent period of denudation ends abruptly with the rapid deposition of the Etendeka basalts in the Early Cretaceous (3). The maximum thickness of the Etendeka volcanic suite has been estimated, using the apatite fission-track data, to about 3.2 (1.2) km. With the ongoing opening of the South Atlantic and the formation of the continental margin the Kaoko Belt went through a rapid cooling event starting ~ 130 Ma and ending ~ 80 Ma, at a mean rate of 0.034 km/Ma for the western, and 0.018 km/Ma for the northern and eastern Kaoko Belt. This cooling event was accompanied by a reactivation of major fault zones, like the Purros Mylonite Zone (4). Thereafter, stable conditions were established, with denudation rates generally lower than 0.010 km/Ma, until the Neogene, where a second cooling event led to increased exhumation rates around 0.042 km/Ma. The total amount of denudation in the last 130 Ma

Long-term subsidence, cooling, and exhumation history along the South Atlantic passive continental margin in NW-Namibia

NASA Astrophysics Data System (ADS)

Menges, Daniel; Glasmacher, Ulrich Anton; Salomon, Eric; Hackspacher, Peter Christian; Schneider, Gabi

2017-04-01

In northwestern Namibia the Kaoko Belt is one of the most important Precambrian crustal segments that have stored the subsidence, cooling, and exhumation history of Namibia since the Neoproterozoic. ZFT-ages, with ages between 292.7 (46.0) and 436.8 (45.9) Ma, are giving new insights on this early evolution. Paleozoic to Mesozoic sedimentary rocks of the Karoo Supergroup and the Lower Cretaceous volcanic rocks of the Etendeka sequence overlay the Proterozoic metamorphic and intrusive rocks (1). New apatite fission-track (AFT) ages range from 390.9 (17.9) Ma to 80.8 (6.0) Ma. Along the coast apatites of Proterozoic rock samples reveal the youngest ages. Further inland the ages increase significantly. In addition, rapid change of AFT-ages occurs on both sides of major thrust and shear zones. Using the oldest thermochronological data the revealed t-T paths indicate a long era of exhumation, starting at the end of the Pan-African Orogeny in the Neoproterozoic and continuing into the Permo-Carboniferous. The subsequent sedimentation of the Karoo Supergroup initiates a new era of subsidence until the end of Triassic (2).The subsequent period of denudation ends abruptly with the rapid deposition of the Etendeka basalts in the Early Cretaceous (3). The maximum thickness of the Etendeka volcanic suite has been estimated, using the apatite fission-track data, to about 3.2 (1.2) km. With the ongoing opening of the South Atlantic and the formation of the continental margin the Kaoko Belt went through a rapid cooling event starting 130 Ma and ending 80 Ma, at a mean rate of 0.034 km/Ma for the western, and 0.018 km/Ma for the northern and eastern Kaoko Belt. This cooling event was accompanied by a reactivation of major fault zones, like the Purros Mylonite Zone (4). Thereafter, stable conditions were established, with denudation rates generally lower than 0.010 km/Ma, until the Neogene, where a second cooling event led to increased exhumation rates around 0.042 km/Ma. The total

Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland

PubMed Central

Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M.; Edvardsson, Ragnar; Pálsson, Snæbjörn

2014-01-01

Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500–1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400–1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change. PMID:24403343

Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland.

PubMed

Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M; Edvardsson, Ragnar; Pálsson, Snæbjörn

2014-02-22

Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500-1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400-1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change.

Application of Diversity Indices to Quantify Early Life-History Diversity for Chinook Salmon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.

2014-03-01

We developed an index of early life history diversity (ELHD) for Pacific salmon (Oncorhynchus spp.) Early life history diversity is the variation in morphological and behavioral traits expressed within and among populations by individual juvenile salmon during their downstream migration. A standard quantitative method does not exist for this prominent concept in salmon biology.

An Impaired View of Earth's Early History

NASA Astrophysics Data System (ADS)

Vervoort, J. D.; Kemp, A. I.; Bauer, A.; Bowring, S. A.; Fisher, C.

2014-12-01

The Hf and Nd isotope records of Earth's early history are sparse, difficult to interpret, and controversial, much like the few remnants of crust older than 4 Ga. New analytical techniques have been brought to bear on this problem but despite this recent work­-or, perhaps, because of it-the record is no clearer than it was 15 years ago. Several studies, based on highly variable calculated initial isotopic compositions, have argued for highly heterogeneous crust and mantle reservoirs in the early Earth1,2 and an ultra-depleted Eoarchean mantle3. These data come mostly from two sources: Hf-Nd isotope analyses of ultramafic rocks and Hf isotope analyses of zircons by solution or laser ablation. An important question for understanding the chemical evolution of the early Earth is: Do these data offer a unique window into the early Earth or are they artefacts not representative of crust/mantle evolution, giving an impaired view of the Earth's early history? In complex samples, measured isotopic compositions can result from open-system behavior in easily altered ultramafic compositions, in multicomponent, polymetamorphic gneisses, or in zircons with multiple generations of growth. Perhaps most importantly, accurate age assignment is often lacking, compromised, or impossible in these rocks, making calculation of initial epsilon Hf and Nd values ambiguous at best. In order to gain insight into crust mantle evolution in the early Earth we need, above all, a robust and unambiguous isotopic record to work with. This can be achieved by integrating zircon U-Pb and Hf and whole-rock Hf and Nd isotope compositions in relatively undisturbed igneous rocks with well-constrained ages. When this approach is used apparent isotopic heterogeneity decreases and a simpler model for crust-mantle evolution in the early Earth emerges. Careful screening of geological relationships, petrology, and geochemistry of samples from the early Earth should be done before interpreting isotopic data

The Cooling History and Structure of the Ordinary Chondrite Parent Bodies

NASA Technical Reports Server (NTRS)

Benoit, P. H.; Sears, D. W. G.

1996-01-01

Most major meteorite classes exhibit significant ranges of metamorphism. The effects of metamorphism have been extensively characterized, but the heat source(s) and the metamorphic environment are unknown. Proposed beat sources include Al-26, Fe-60, electromagnetic induction, and impact. It is typically assumed that metamorphism occurred in parent bodies of some sort, but it uncertain whether these bodies were highly structured ("onion skins") or were chaotic mixes of material ("rubble piles"). The lack of simple trends of metallographic cooling rates with petrologic type has been considered supportive of both concepts. In this study, we use induced thermoluminescence (TL) as an indicator of thermal history. The TL of ordinary chondrites is produced by sodic feldspar, and the induced TL peak temperature is related to its crystallographic order/disorder. Ordered feldspar has TL peak temperatures of approx. 120 C, and disordered feldspar has TL peak temperatures of approx. 220 C. While ordered feldspar can be easily disordered in the laboratory by heating above 650 C and is easily quenched in the disordered form, producing ordered feldspar requires cooling at geologic cooling rates. We have measured the induced TL properties of 101 equilibrated ordinary chondrites, including 49 H, 29 L, and 23 LL chondrites. For the H chondrites there is an apparent trend of decreasing induced TL peak temperature with increasing petrologic type. H4 chondrites exhibit a tight range of TL peak temperatures, 190 C - 200 C, while H6 chondrites exhibit TL peak temperatures between 180 C and 190 C. H5 chondrites cover the range between H4 and H6, and also extend up to 210 C. Similar results are obtained for LL chondfiles and most L6 chondrites have lower induced TL peak temperatures than L5 chondrites.

[The early history of "Ecstasy"].

PubMed

Benzenhöfer, U; Passie, T

2006-01-01

There is no consensus in the literature regarding the early history of MDMA (Methylendioxymethamphetamine, so-called "Ecstasy"). Various authors credit the first synthesis of MDMA to the German chemist Fritz Haber, but it appears neither in his doctoral thesis (Berlin 1891) nor in his accompanying articles. The man who first synthesized MDMA was the chemist Dr. Anton Köllisch, who worked for the German pharmaceutical company Merck. He created MDMA as a by-product while trying to synthesize hydrastinin, a styptic substance. In 1912, Merck filed to patent the applied method of preparation. The patent was issued in 1914, yet no pharmaceutical testing followed at that time.

[Contribution to the history of pharmacology (the early Roman empire)].

PubMed

Tesařová, Drahomíra

2014-01-01

This article is a contribution to the history of pharmacology in the early Roman empire. It contains texts mainly written in Latin: the works of Aulus Cornelius Celsus, Scribonius Largus and Plinius Maior (Pliny the Elder). It describes their structure and contributions to the history of medicine and gives examples of some prescriptions and drugs in the original language and in Czech.

Distribution and severity of hypoxic-ischaemic lesions on brain MRI following therapeutic cooling: selective head versus whole body cooling.

PubMed

Sarkar, Subrata; Donn, Steven M; Bapuraj, Jayapalli R; Bhagat, Indira; Barks, John D

2012-09-01

Whole body cooling (WBC) cools different parts of the brain uniformly, and selective head cooling (SHC) cools the superficial brain more than the deeper brain structures. In this study, the authors hypothesised that the hypoxic-ischaemic lesions on brain MRI following cooling would differ between modalities of cooling. To compare the frequency, distribution and severity of hypoxic-ischaemic lesions on brain MRI between SHC or WBC. In a single centre retrospective study, 83 infants consecutively cooled using either SHC (n=34) or WBC (n=49) underwent brain MRI. MRI images were evaluated by a neuroradiologist, who was masked to clinical parameters and outcomes, using a basal ganglia/watershed (BG/W) scoring system. Higher scores (on a scale of 0 to 4) were given for more extensive injury. The score has been reported to be predictive of neuromotor and cognitive outcome at 12 months. The two groups were similar for severity of depression as assessed by a history of an intrapartum sentinel event, Apgar scores, initial blood pH and base deficit and early neurological examination. However, abnormal MRI was more frequent in the SHC group (SHC 25 of 34, 74% vs WBC 22 of 49, 45%; p=0.0132, OR 3.4, 95% CI 1.3 to 8.8). Infants from the SHC group also had more severe hypoxic-ischaemic lesions (median BG/W score: SHC 2 vs WBC 0, p=0.0014). Hypoxic-ischaemic lesions on brain MRI following therapeutic cooling were more frequent and more severe with SHC compared with WBC.

The Invention and Early History of the N-Localizer for Stereotactic Neurosurgery

PubMed Central

Nelson, James A

2016-01-01

Nearly four decades after the invention of the N-localizer, its origin and history remain misunderstood. Some are unaware that a third-year medical student invented this technology. The following conspectus accurately chronicles the origin of the N-localizer, presents recently discovered evidence that documents its history, and corrects misconceptions related to its origin and early history. PMID:27462476

Early history of Neanderthals and Denisovans

PubMed Central

Bohlender, Ryan J.; Huff, Chad D.

2017-01-01

Extensive DNA sequence data have made it possible to reconstruct human evolutionary history in unprecedented detail. We introduce a method to study the past several hundred thousand years. Our results show that (i) the Neanderthal–Denisovan lineage declined to a small size just after separating from the modern lineage, (ii) Neanderthals and Denisovans separated soon thereafter, and (iii) the subsequent Neanderthal population was large and deeply subdivided. They also (iv) support previous estimates of gene flow from Neanderthals into modern Eurasians. These results suggest an archaic human diaspora early in the Middle Pleistocene. PMID:28784789

Cooling flows and X-ray emission in early-type galaxies

NASA Technical Reports Server (NTRS)

Sarazin, Craig L.

1990-01-01

The X-ray properties of normal early-type galaxies and the limited theoretical understanding of the physics of the hot interstellar medium in these galaxies are reviewed. A number of simple arguments about the physical state of the gas are given. Steady-state cooling flow models for these galaxies are presented, and their time-dependent evolution is discussed. The X-ray emission found in early-type galaxies indicates that they contain significant amounts of hot interstellar gas, and that they are not the gas-poor systems they were previously thought to be. In the brighter X-ray galaxies, the amounts of hot gas observed are consistent with those expected given the present rates of stellar mass loss. The required rates of heating of the gas are consistent with those expected from the motions of gas-losing stars and supernovae. The X-ray observations are generally more consistent with a lower rate of Type I supernovae than was previously thought.

NASA Microclimate Cooling Challenges

NASA Technical Reports Server (NTRS)

Trevino, Luis A.

2004-01-01

The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.

History in the Early Nineteenth Century.

PubMed

Ratcliff, Jessica

2016-09-01

At the turn of the nineteenth century, at its headquarters in the City of London, the Honourable East India Company established a new museum and library. By midcentury this museum would contain one of Europe’s most extensive collections of the natural history, arts, and sciences of Asia. This essay uses the early history of the company’s museum, focusing in particular on its natural history collections, to explore the material relationship between scientific practice and the imperial political economy. Much of the collections had been gathered in the wake of military campaigns, trade missions, or administrative surveys. Once specimens and reports arrived in Leadenhall Street and passed through the museum storage areas, this plunder would become the stuff of science, going on to feed the growth of disciplines, societies, and projects in Britain and beyond. In this way, the East India Company was integral to the information and communication infrastructures within which many sciences then operated. Collections-based disciplines and societies flourished in this period; their growth, it is argued, was coextensive with administrative and political economic change at institutions like the East India Company. The essay first explores the company’s practices and patterns of collecting and then considers the consequences of this accumulation for aspects of scientific practice—particularly the growth of scientific societies—in both London and Calcutta.

An early history of T cell-mediated cytotoxicity.

PubMed

Golstein, Pierre; Griffiths, Gillian M

2018-04-16

After 60 years of intense fundamental research into T cell-mediated cytotoxicity, we have gained a detailed knowledge of the cells involved, specific recognition mechanisms and post-recognition perforin-granzyme-based and FAS-based molecular mechanisms. What could not be anticipated at the outset was how discovery of the mechanisms regulating the activation and function of cytotoxic T cells would lead to new developments in cancer immunotherapy. Given the profound recent interest in therapeutic manipulation of cytotoxic T cell responses, it is an opportune time to look back on the early history of the field. This Timeline describes how the early findings occurred and eventually led to current therapeutic applications.

A qualitative study of early family histories and transitions of homeless youth.

PubMed

Tyler, Kimberly A

2006-10-01

Using intensive qualitative interviews with 40 homeless youth, this study examined their early family histories for abuse, neglect, and other family problems and the number and types of transitions that youth experienced. Multiple forms of child maltreatment, family alcoholism, drug use, and criminal activity characterized early family histories of many youth. Leaving home because of either running away or being removed by child protective services often resulted in multiple transitions, which regularly included moving from foster care homes to a group home, back to their parents, and then again returning to the streets. Although having experienced family disorganization set youth on trajectories for early independence, there were many unique paths that youth traveled prior to ending up on the streets.

Early history of Vesta: implications for the surface morphology and composition

NASA Astrophysics Data System (ADS)

Turrini, D.; Coradini, A.; Formisano, M.; Carli, C.; Magni, G.

2011-12-01

The Dawn mission inserted into orbit around Vesta on 15 July 2011 and is presently gathering data on the morphology and the composition of the asteroid. In order to fully exploit the data that the Dawn mission is supplying to probe the ancient past of our Solar System, we need to be able to understand how the present state of Vesta is linked to its origin and its secular evolution. The spectral connection between Vesta and the Howardite-Eurcrite-Diogenite (HED) suite of meteorites suggests that Vesta formed very early in the history of the Solar System and differentiated on a Ma-long timescale due to the decay of short-lived radioactive nuclides (see Keil 2002 and references therein). Short after the differentiation process ended, Vesta started to cool down quickly, so that on a 10 Ma timescale its molten mantle would be topped by a thick solid layer (Formisano et al. 2011). Across the same timespan, Jupiter and the other giant planets would form in the outer Solar System and trigger a primordial phase of bombardment on the other already formed planetary bodies (Turrini et al. 2011, Coradini et al. 2011). Such primordial bombardment is expected to excavate the solid crust of Vesta and to cause local to regional effusive phenomena (Turrini et al. 2011). Moreover, due to the relatively high escape speed from Vesta, most of the excavated material would fall back on the asteroid as an ejecta blanket. Here we discuss the timescale of the formation and evolution of Vesta and the implications for the interpretation of the data that the Dawn mission is collecting while orbiting the asteroid. Bibliography 1. Coradini A., Turrini D., Federico C., Magni G. (2011). Vesta and Ceres: crossing the history of the Solar System. Space Science Reviews, DOI: 10.1007/s11214-011-9792-x. 2. Formisano M., Federico C., Coradini A. (2011). Vesta Thermal Models. EPSC-DPS Joint Meeting 2011, Nantes, France. 3. Keil K. (2002). Geological History of Asteroid 4 Vesta: The Smallest Terrestrial

Microstructural and paleomagnetic insight into the cooling history of the IAB parent body

NASA Astrophysics Data System (ADS)

Nichols, Claire I. O.; Krakow, Robert; Herrero-Albillos, Julia; Kronast, Florian; Northwood-Smith, Geraint; Harrison, Richard J.

2018-05-01

The IABs represent one of only two groups of iron meteorites that did not form by fractional crystallization of liquid Fe-Ni in the core of a differentiated planetesimal. Instead, they are believed to originate from a partially differentiated body that was severely disrupted by one or more impacts during its early history. We present a detailed microstructural and paleomagnetic study of the Odessa and Toluca IAB meteorites, with a view to further constraining the complex history of the IAB parent body. X-ray photoemission electron microscopy and energy dispersive spectroscopy were used to generate high-resolution Ni/Fe maps. The crystallographic architecture of Odessa was analysed using electron backscatter diffraction. Paleomagnetic signals and the magnetic properties of several microstructures were also assessed using X-ray magnetic circular dichroism. Odessa exhibits a complex series of microstructures, requiring an unusual evolution during slow cooling. A conventional Widmanstätten microstructure, consisting of multiple generations of kamacite lamellae surrounded by M-shaped diffusion profiles, developed via continuous precipitation to temperatures below ∼400 °C. Multiple generations of pearlitic plessite nucleated from kamacite/taenite (T > 400 °C) and tetrataenite rim/taenite interfaces (T < 400 °C), via a process of discontinuous precipitation. Rounded rafts of Ni-rich taenite, observed within some regions of pearlitic plessite, are shown to have the same crystallographic orientation as the parental taenite, and a non-standard orientation relationship with the enclosing kamacite. Contrary to current theories, these rafts cannot have formed by coarsening of pre-existing pearlitic plessite. A new bowing mechanism is proposed, whereby rafts of Ni-enriched taenite form between advancing lobes of an irregular reaction front during discontinuous precipitation. Subsequent coarsening leads to the growth of the taenite rafts, and the partial or complete removal

Early history of the pre-excitation syndrome.

PubMed

Hanon, Sam; Shapiro, Michael; Schweitzer, Paul

2005-01-01

This brief review discusses the interesting early history of the pre-excitation syndrome. In 1913 Cohn and Fraser published the first patient with a short P-R interval, wide QRS complexes, and paroxysmal tachycardia. This was followed by other cases of pre-excitation syndrome, all of which were considered to be due to bundle branch blocks. In 1930 Wolff, Parkinson, and White reported 11 patients with the syndrome, which came to bear their name. Two years later, Holzmann and Scherf suggested bypass tracts as the most likely mechanism of pre-excitation syndrome. In 1942, Wood et al. documented the first accessory connection at autopsy. Despite these early studies supporting the bypass theory, the quest for alternative mechanisms continued until the 1970s when electrophysiological studies and surgical therapy confirmed accessory connections as the mechanism of pre-excitation syndrome.

A cooling neutron star crust after recurrent outbursts: modelling the accretion outburst history of Aql X-1

NASA Astrophysics Data System (ADS)

Ootes, Laura S.; Wijnands, Rudy; Page, Dany; Degenaar, Nathalie

2018-07-01

With our neutron star crust cooling code NSCOOL, we track the thermal evolution of the neutron star in Aql X-1 over the full accretion outburst history from 1996 until 2015. For the first time, we model many outbursts (23 outbursts were detected) collectively and in great detail. This allows us to investigate the influence of previous outbursts on the internal temperature evolution and to test different neutron star crust cooling scenarios. Aql X-1 is an ideal test source for this purpose, because it shows frequent, short outbursts and thermally dominated quiescence spectra. The source goes into outburst roughly once a year for a few months. Assuming that the quiescent Swift/X-Ray Telescope observations of Aql X-1 can be explained within the crust cooling scenario, we find three main conclusions. First, the data are well reproduced by our model if the envelope composition and shallow heating parameters are allowed to change between outbursts. This is not the case if both shallow heating parameters (strength and depth) are tied throughout all accretion episodes, supporting earlier results that the properties of the shallow heating mechanism are not constant between outbursts. Secondly, from our models, shallow heating could not be connected to one specific spectral state during outburst. Thirdly, and most importantly, we find that the neutron star in Aql X-1 does not have enough time between outbursts to cool down to crust-core equilibrium and that heating during one outburst influences the cooling curves of the next.

The cooling history and the depth of detachment faulting at the Atlantis Massif oceanic core complex

NASA Astrophysics Data System (ADS)

Schoolmeesters, Nicole; Cheadle, Michael J.; John, Barbara E.; Reiners, Peter W.; Gee, Jeffrey; Grimes, Craig B.

2012-10-01

Oceanic core complexes (OCCs) are domal exposures of oceanic crust and mantle interpreted to be denuded to the seafloor by large slip oceanic detachment faults. We combine previously reported U-Pb zircon crystallization ages with (U-Th)/He zircon thermochronometry and multicomponent magnetic remanence data to determine the cooling history of the footwall to the Atlantis Massif OCC (30°N, MAR) and help establish cooling rates, as well as depths of detachment faulting and gabbro emplacement. We present nine new (U-Th)/He zircon ages for samples from IODP Hole U1309D ranging from 40 to 1415 m below seafloor. These data paired with U-Pb zircon ages and magnetic remanence data constrain cooling rates of gabbroic rocks from the upper 800 m of the central dome at Atlantis Massif as 2895 (+1276/-1162) °C Myr-1 (from ˜780°C to ˜250°C); the lower 600 m of the borehole cooled more slowly at mean rates of ˜500 (+125/-102) °C Myr-1(from ˜780°C to present-day temperatures). Rocks from the uppermost part of the hole also reveal a brief period of slow cooling at rates of ˜300°C Myr-1, possibly due to hydrothermal circulation to ˜4 km depth through the detachment fault zone. Assuming a fault slip rate of 20 mm/yr (from U-Pb zircon ages of surface samples) and a rolling hinge model for the sub-surface fault geometry, we predict that the 780°C isotherm lies at ˜7 km below the axial valley floor, likely corresponding both to the depth at which the semi-brittle detachment fault roots and the probable upper limit of significant gabbro emplacement.

Conodont geothermometry in pyroclastic kimberlite: constraints on emplacement temperatures and cooling histories

NASA Astrophysics Data System (ADS)

Pell, Jennifer; Russell, James K.; Zhang, Shunxin

2018-03-01

Kimberlite pipes from Chidliak, Baffin Island, Nunavut, Canada host surface-derived Paleozoic carbonate xenoliths containing conodonts. Conodonts are phosphatic marine microfossils that experience progressive, cumulative and irreversible colour changes upon heating that are experimentally calibrated as a conodont colour alteration index (CAI). CAI values permit us to estimate the temperatures to which conodont-bearing rocks have been heated. Conodonts have been recovered from 118 samples from 89 carbonate xenoliths collected from 12 of the pipes and CAI values within individual carbonate xenoliths show four types of CAI distributions: (1) CAI values that are uniform throughout the xenolith; (2) lower CAIs in core of a xenolith than the rim; (3) CAIs that increase from one side of the xenolith to the other; and, (4) in one xenolith, higher CAIs in the xenolith core than at the rim. We have used thermal models for post-emplacement conductive cooling of kimberlite pipes and synchronous heating of conodont-bearing xenoliths to establish the temperature-time history of individual xenoliths within the kimberlite bodies. Model results suggest that the time-spans for xenoliths to reach the peak temperatures recorded by CAIs varies from hours for the smallest xenoliths to 2 or 3 years for the largest xenoliths. The thermal modelling shows the first three CAI patterns to be consistent with in situ conductive heating of the xenoliths coupled to the cooling host kimberlite. The fourth pattern remains an anomaly.

Multiple cooling episodes in the Central Tarim (Northwest China) revealed by apatite fission track analysis and vitrinite reflectance data

NASA Astrophysics Data System (ADS)

Chang, Jian; Qiu, Nansheng; Song, Xinying; Li, Huili

2016-06-01

Apatite fission track and vitrinite reflectance are integrated for the first time to study the cooling history in the Central Tarim, northwest China. The paleo-temperature profiles from vitrinite reflectance data of the Z1 and Z11 wells showed a linear relationship with depth, suggesting an approximately 24.8 °C/km paleo-geothermal gradient and 2700-3900 m of erosion during the Early Mesozoic. The measured apatite fission track ages from well Z2 in the Central Tarim range from 39 to 159 Ma and effectively record the Meso-Cenozoic cooling events that occurred in Central Tarim. Moreover, two cooling events at 190-140 Ma in the Early Jurassic-Early Cretaceous and 80-45 Ma in the Late Cretaceous-Paleocene revealed by measured AFT data and thermal modeling results are related to the collisions of the Qiangtang-Lhasa terranes and the Greater India Plate with the southern margin of the Eurasian Plate, respectively. This study provides new insights into the tectonic evolution of the Tarim Basin (and more broadly Central Asia) and for hydrocarbon generation and exploration in the Central Tarim.

History and early development of INCAP.

PubMed

Scrimshaw, Nevin S

2010-02-01

Nevin Scrimshaw was the founding Director of the Institute of Nutrition of Central America and Panama (INCAP), serving as Director from 1949 to 1961. In this article, he reviews the history of the founding of INCAP, including the role of the Rockefeller and Kellogg Foundations, the Central American governments, and the Pan American Health Organization. The objectives pursued by INCAP in its early years were to assess the nutrition and related health problems of Central America, to carry out research to find practical solutions to these problems, and to provide technical assistance to its member countries to implement solutions. INCAP pursued a strategy of selecting promising Central Americans for advanced education and training in the US who assumed positions of leadership on their return. After this early phase, talented non-Central Americans of diverse origins were brought to INCAP, as well as additional researchers from the region. Growth of INCAP, as reflected in its annual budget and in the physical plant, was rapid and this was accompanied by high scientific productivity. Several field studies were launched that contributed impetus and design elements for the Oriente Longitudinal Study, which is the focus of this supplement.

Multiplicity of the Galactic Senior Citizens: A high-resolution search for cool subdwarf companions

NASA Astrophysics Data System (ADS)

Ziegler, Carl; Law, Nicholas M.

2015-01-01

Cool subdwarfs, with spectral types late K and M, are the oldest members of the low-mass stellar population. Mostly present in the galactic halo, subdwarfs are characterized by their low metallicity and high proper-motions. Understanding their binary fraction could give key insights into the star formation process early in the Milky Way's history. However, because of their low luminosity and relative rarity in the solar neighborhood, binary surveys of cool subdwarfs have suffered from small sample sizes and large incompleteness gaps. It appears, however, that the binary fraction of red subdwarfs is much lower than for their main-sequence cousins. Using the highly efficient Robo-AO system, we present the largest high-resolution survey of subdwarfs yet. We find from 349 target cool subdwarfs, 39 are in multiple systems, 13 newly discovered, for a binary fraction of 11 ± 1.8%.

Assessment of the cooling capacity of plate tectonics and flood volcanism in the evolution of Earth, Mars and Venus

NASA Astrophysics Data System (ADS)

van Thienen, P.; Vlaar, N. J.; van den Berg, A. P.

2005-06-01

Geophysical arguments against plate tectonics in a hotter Earth, based on buoyancy considerations, require an alternative means of cooling the planet from its original hot state to the present situation. Such an alternative could be extensive flood volcanism in a more stagnant-lid like setting. Starting from the notion that all heat output of the Earth is through its surface, we have constructed two parametric models to evaluate the cooling characteristics of these two mechanisms: plate tectonics and basalt extrusion/flood volcanism. Our model results show that for a steadily (exponentially) cooling Earth, plate tectonics is capable of removing all the required heat at a rate of operation comparable to or even lower than its current rate of operation, contrary to earlier speculations. The extrusion mechanism may have been an important cooling agent in the early Earth, but requires global eruption rates two orders of magnitude greater than those of known Phanerozoic flood basalt provinces. This may not be a problem, since geological observations indicate that flood volcanism was both stronger and more ubiquitous in the early Earth. Because of its smaller size, Mars is capable of cooling conductively through its lithosphere at significant rates, and as a result may have cooled without an additional cooling mechanism. Venus, on the other hand, has required the operation of an additional cooling agent for probably every cooling phase of its possibly episodic history, with rates of activity comparable to those of the Earth.

Conversational Language Use as a Predictor of Early Reading Development: Language History as a Moderating Variable

PubMed Central

DeThorne, Laura Segebart; Petrill, Stephen A.; Schatschneider, Chris; Cutting, Laurie

2010-01-01

Purpose The present study examined the nature of concurrent and predictive associations between conversational language use and reading development during early school-age years. Method Language and reading data from 380 twins in the Western Reserve Reading Project were examined via phenotypic correlations and multilevel modeling on exploratory latent factors. Results In the concurrent prediction of children’s early reading abilities, a significant interaction emerged between children’s conversational language abilities and their history of reported language difficulties. Specifically, conversational language concurrently predicted reading development above and beyond variance accounted for by formal vocabulary scores, but only in children with a history of reported language difficulties. A similar trend was noted in predicting reading skills 1 year later, but the interaction was not statistically significant. Conclusions Findings suggest a more nuanced view of the association between spoken language and early reading than is commonly proposed. One possibility is that children with and without a history of reported language difficulties rely on different skills, or the same skills to differing degrees, when completing early reading-related tasks. Future studies should examine the causal link between conversational language and early reading specifically in children with a history of reported language difficulties. PMID:20150410

Pre-mare cratering and early solar system history

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wetherill, G.W.

1974-01-01

An evaluation of the application of the high extra-lunar flux in pre- mare times to more general problems of early solar system history is attempted by combining the results of dynamic studies with lunar chronological data. Dynamical studies permit separate evaluation of the possible sources for both the normal flux during the first 600 m.y. years of lunar history as well as the peak which apparently occurred 4.0 b.y. ago. Dynamical studies have been carried out in order to determine the extent to which a heliocentric flux could be confined to the Moon (and Earth). A Monte Carlo method hasmore » been used to calculate the relative impact rates of planet-crossing bodies with the moon and the terrestrial planets. It is concluded that the time-variation of the flux on these planets is closely related to that on the moon. (STAR)« less

Metallographic cooling rates of L-group ordinary chondrites

NASA Technical Reports Server (NTRS)

Bennett, Marvin E.; Mcsween, Harry Y., Jr.

1993-01-01

Shock metamorphism appears to be a ubiquitous feature in L-group ordinary chondrites. Brecciation and heterogeneous melting obscure much of the early history of this meteorite group and have caused confusion as to whether L chondrites have undergone thermal metamorphism within onion-shell or rubble-pile parent bodies. Employing the most recent shock criteria, we have examined 55 Antarctic and 24 non-Antarctic L chondrites in order to identify those which have been least affected by post-accretional shock. Six low-shock samples (those with shock grade less than S4) of petrographic types L3-L5 were selected from both populations and metallographic cooling rates were obtained following the technique of Willis and Goldstein. All non-Antarctic L6 chondrites inspected were too heavily shocked to be included in this group. However, 4 shocked L6 chondrites were analyzed in order to determine what effects shock may impose on metallographic cooling rates. Metallographic cooling rates were derived by analyzing the cores of taenite grains and then measuring the distance to the nearest grain edge. Taenites were identified using backscatter imaging on a Cameca SX-50 electron microprobe. Using backscatter we were able to locate homogeneous, rust-free, nearly spherical grains. M-shaped profiles taken from grain traverses were also used to help locate the central portions of selected grains. All points which contained phosphorus above detection limits were discarded. Plots of cooling-rate data are summarized and data from the high-shock samples are presented. The lack of coherency of cooling rates for individual samples is indicative of heterogeneous cooling following shock. The data confirms the statement expressed by numerous workers that extreme care must be taken when selecting samples of L chondrites for cooling-rate studies. Data for the 6 non-Antarctic low-shock samples are also presented. The samples display a general trend in cooling rates. The lowest metamorphic grade

Late Cenozoic cooling history of the central Menderes Massif and the contribution of erosion to rock exhumation during active continental extension

NASA Astrophysics Data System (ADS)

Nilius, Nils-Peter; Wölfler, Andreas; Heineke, Caroline; Glotzbach, Christoph; Hetzel, Ralf; Hampel, Andrea; Akal, Cüneyt; Dunkl, István

2017-04-01

The Menderes Massif constitutes the western part of the Anatolide belt in western Turkey and experienced a prolonged history of post-orogenic extension. A large amount of the extension was accommodated by the two oppositely dipping Gediz and Büyük Menderes detachment faults, which led to the exhumation of the central Menderes Massif (Gessner et al., 2013). Previous studies proposed a synchronous, bivergent exhumation of the central Menderes Massif since the Miocene (Gessner et al., 2001), although only the evolution of the north-dipping Gediz detachment is well constrained (Buscher et al., 2013). Detailed structural and thermochronological investigations from the south-dipping Büyük Menderes detachment have still been missing. Here we present results from different thermochronometers, which constrain the cooling and exhumation history of footwall and hanging wall rocks of the Büyük Menderes detachment. Our new zircon and apatite (U-Th)/He and fission track ages of footwall rocks from the Büyük Menderes detachment document two phases of increased cooling and exhumation (Wölfler et al., in revision). The first episode of increased footwall exhumation ( 0.9 km/Myr) occurred during the middle Miocene, followed by a second phase during latest Miocene and Pliocene ( 1.0 km/Myr). Apatite fission track ages yield a slip rate for the Pliocene movement along the Büyük Menderes detachment of 3.0 (+1.1/-0.6) km/Myr. Thermochronological data of hanging wall units reflect a slow phase of exhumation ( 0.2 km/Myr) in the late Oligocene and an increased exhumation rate of 1.0 km/Myr during the early to middle Miocene, when hanging wall units cooled below 80 °C. In comparison with the Gediz detachment, our thermochronological data from the Büyük Menderes detachment confirms the concurrent activity of both detachments during the late Miocene and Pliocene. With respect to the relative importance of normal faulting and erosion to rock exhumation, a comparison with 10Be

The cooling rates of pahoehoe flows: The importance of lava porosity

NASA Technical Reports Server (NTRS)

Jones, Alun C.

1993-01-01

Many theoretical models have been put forward to account for the cooling history of a lava flow; however, only limited detailed field data exist to validate these models. To accurately model the cooling of lava flows, data are required, not only on the heat loss mechanisms, but also on the surface skin development and the causes of differing cooling rates. This paper argues that the cause of such variations in the cooling rates are attributed, primarily, to the vesicle content and degassing history of the lava.

Notes on the Early History of Technical Higher

NASA Astrophysics Data System (ADS)

Teodorescu, Horia Nicolai

We perform a brief analysis of the economical and political context of establishing the first technical higher school in Romania. We urge for a revision of the current point of view on the educational level in Yashi (Iaši) and Bucharest at the epoch, highlighting that these were, at the time, important academic centers we may not recognize or may not be aware of today. We also plead for a long due serious approach about the history of early modern education in Romania.

A history of early geologic research in the Deep River Triassic Basin, North Carolina

USGS Publications Warehouse

Clark, T.W.

1998-01-01

The Deep River Triassic basin has one of the longest recorded histories of geologic research in North Carolina. A quick perusal of nineteenth century geologic literature in North Carolina reveals the Deep River basin has received a tremendous amount of attention, second only, perhaps, to the gold deposits of the Carolina slate belt. While these early researchers' primary interests were coal deposits, many other important discoveries, observations, and hypotheses resulted from their investigations. This article highlights many of the important advances made by these early geo-explorers by trying to include information from every major geologic investigation made in the Deep River basin from 1820 to 1955. This article also provides as thorough a consolidated history as is possible to preserve the exploration history of the Deep River basin for future investigators.

Post-breakup tectonics in southeast Brazil from thermochronological data and combined inverse-forward thermal history modeling

NASA Astrophysics Data System (ADS)

Cogné, Nathan; Gallagher, Kerry; Cobbold, Peter R.; Riccomini, Claudio; Gautheron, Cecile

2012-11-01

The continental margin of southeast Brazil is elevated. Onshore Tertiary basins and Late Cretaceous/Paleogene intrusions are good evidence for post breakup tectono-magmatic activity. To constrain the impact of post-rift reactivation on the geological history of the area, we carried out a new thermochronological study. Apatite fission track ages range from 60.7 ± 1.9 Ma to 129.3 ± 4.3 Ma, mean track lengths from 11.41 ± 0.23 μm to 14.31 ± 0.24 μm and a subset of the (U-Th)/He ages range from 45.1 ± 1.5 to 122.4 ± 2.5 Ma. Results of inverse thermal history modeling generally support the conclusions from an earlier study for a Late Cretaceous phase of cooling. Around the onshore Taubaté Basin, for a limited number of samples, the first detectable period of cooling occurred during the Early Tertiary. The inferred thermal histories for many samples also imply subsequent reheating followed by Neogene cooling. Given the uncertainty of the inversion results, we did deterministic forward modeling to assess the range of possibilities of this Tertiary part of the thermal history. The evidence for reheating seems to be robust around the Taubaté Basin, but elsewhere the data cannot discriminate between this and a less complex thermal history. However, forward modeling results and geological information support the conclusion that the whole area underwent cooling during the Neogene. The synchronicity of the cooling phases with Andean tectonics and those in NE Brazil leads us to assume a plate-wide compressional stress that reactivated inherited structures. The present-day topographic relief of the margin reflects a contribution from post-breakup reactivation and uplift.

Cool episode and platform demise in the Early Aptian: New insights on the links between climate and carbonate production

NASA Astrophysics Data System (ADS)

Bonin, Aurélie; Pucéat, Emmanuelle; Vennin, Emmanuelle; Mattioli, Emanuela; Aurell, Marcos; Joachimski, Michael; Barbarin, Nicolas; Laffont, Rémi

2016-01-01

The Early Aptian encountered several crises in neritic and pelagic carbonate production, major perturbations in the carbon cycle, and an oceanic anoxic event (OAE1a). Yet the causal links between these perturbations and climate changes remain poorly understood, partly because temperature records spanning the Early Aptian interval are still scant. We present new δ18O data from well-preserved bivalves from a carbonate platform of the Galve subbasin (Spain) that document a major cooling event postdating most of OAE1a. Our data show that cooling postdates the global platform demise and cannot have triggered this event that occurred during the warmest interval. The warmest temperatures coincide with the time equivalent of OAE1a and with platform biotic assemblages dominated by microbialites at Aliaga as well as on other Tethyan platforms. Coral-dominated assemblages then replace microbialites during the subsequent cooling. Nannoconids are absent during most of the time equivalent of the OAE1a, probably related to the well-known crisis affecting this group. Yet they present a transient recovery in the upper part of this interval with an increase in both size and abundance during the cool interval portion that postdates OAE1a. An evolution toward cooler and drier climatic conditions may have induced the regional change from microbial to coral assemblages as well as nannoconids size and abundance increase by limiting continent-derived input of nutrients.

Parental care mitigates carry-over effects of poor early conditions on offspring growth

USGS Publications Warehouse

Auer, Sonya K.; Martin, Thomas E.

2017-01-01

Poor developmental conditions can have long-lasting negative effects on offspring phenotypes, but impacts often differ among species. Contrasting responses may reflect disparities in experimental protocols among single-species studies or inherent differences among species in their sensitivity to early conditions and/or ability to mitigate negative impacts. We used a common experimental protocol to assess and compare the role of parental care in mitigating effects of poor early conditions on offspring among 4 sympatric bird species in the wild. We experimentally induced low incubation temperatures and examined effects on embryonic developmental rates, hatching success, nestling growth rates, and parental responses. We examined the generality of these effects across 4 species that differ in their phylogenetic history, breeding ecology, and life histories. We found that cooling led to delayed hatching in all species, but carry-over effects on offspring differed among species. Parents of some but not all species increased their offspring provisioning rates in response to experimental cooling with critical benefits for offspring growth rates. Our study shows for the first time that species exhibit clear differences in the degree to which they are affected by poor early conditions. Observed differences among species demonstrate that parental care is a critical mechanism for mitigating potential negative effects on offspring and suggest that parental responses may be constrained to varying degrees by ecology and life histories.

A Third Note: Helmholtz, Palestrina, and the Early History of Musicology.

PubMed

Kursell, Julia

2015-06-01

This contribution focuses on Hermann von Helmholtz's work on Renaissance composer Giovanni Pierluigi da Palestrina. Helmholtz used his scientific concept of distortion to analyze this music and, reversely, to find corroboration for the concept in his musical analyses. In this, his work interlocked with nineteenth-century aesthetic and scholarly ideals. His eagerness to use the latest products of historical scholarship in early music reveals a specific view of music history. Historical documents of music provide the opportunity for the discovery of new experimental research topics and thereby also reveal insights into hearing under different conditions. The essay argues that this work occupies a peculiar position in the history of musicology; it falls under the header of "systematic musicology," which eventually emerged as a discipline of musicology at the end of the nineteenth century. That this discipline has a history at all is easily overlooked, as many of its contributors were scientists with an interest in music. A history of musicology therefore must consider at least the following two caveats: parts of it take place outside the institutionalized field of musicology, and any history of musicology must, in the last instance, be embedded in a history of music.

Evolution of CO2 and H2O on Mars: A cold Early History?

NASA Technical Reports Server (NTRS)

Niles, P. B.; Michalski, J.

2011-01-01

The martian climate has long been thought to have evolved substantially through history from a warm and wet period to the current cold and dry conditions on the martian surface. This view has been challenged based primarily on evidence that the early Sun had a substantially reduced luminosity and that a greenhouse atmosphere would be difficult to sustain on Mars for long periods of time. In addition, the evidence for a warm, wet period of martian history is far from conclusive with many of the salient features capable of being explained by an early cold climate. An important test of the warm, wet early Mars hypothesis is the abundance of carbonates in the crust [1]. Recent high precision isotopic measurements of the martian atmosphere and discoveries of carbonates on the martian surface provide new constraints on the evolution of the martian atmosphere. This work seeks to apply these constraints to test the feasibility of the cold early scenario

Still Missing? History Chapters in Introductory Early Childhood Education Textbooks From the 1990s to the 2010s

ERIC Educational Resources Information Center

Prochner, Larry; Woitte, Sherry

2013-01-01

This article compares history chapters in recent introductory early childhood education textbooks with those from an earlier study, reviewing history chapters on four dimensions: the rationale for the study of history, the dominant story of the history, the facts of the history, and the image of the history. Ten textbooks are reviewed, including…

Cooling rates of lunar volcanic glass beads

NASA Astrophysics Data System (ADS)

Hui, H.; Hess, K. U.; Zhang, Y.; Peslier, A. H.; Lange, R. A.; Dingwell, D. B.; Neal, C. R.

2016-12-01

It is widely accepted that the Apollo 15 green and Apollo 17 orange glass beads are of volcanic origin. The diffusion profiles of volatiles in these glass beads are believed to be due to degassing during eruption (Saal et al., 2008). The degree of degassing depends on the initial temperature and cooling rate. Therefore, the estimations of volatiles in parental magmas of lunar pyroclastic deposits depend on melt cooling rates. Furthermore, lunar glass beads may have cooled in volcanic environments on the moon. Therefore, the cooling rates may be used to assess the atmospheric condition in an early moon, when volcanic activities were common. The cooling rates of glasses can be inferred from direct heat capacity measurements on the glasses themselves (Wilding et al., 1995, 1996a,b). This method does not require knowledge of glass cooling environments and has been applied to calculate the cooling rates of natural silicate glasses formed in different terrestrial environments. We have carried out heat capacity measurements on hand-picked lunar glass beads using a Netzsch DSC 404C Pegasus differential scanning calorimeter at University of Munich. Our preliminary results suggest that the cooling rate of Apollo 17 orange glass beads may be 12 K/min, based on the correlation between temperature of the heat capacity curve peak in the glass transition range and glass cooling rate. The results imply that the parental magmas of lunar pyroclastic deposits may have contained more water initially than the early estimations (Saal et al., 2008), which used higher cooling rates, 60-180 K/min in the modeling. Furthermore, lunar volcanic glass beads could have been cooled in a hot gaseous medium released from volcanic eruptions, not during free flight. Therefore, our results may shed light on atmospheric condition in an early moon.

Cooling Rates of Lunar Volcanic Glass Beads

NASA Technical Reports Server (NTRS)

Hui, Hejiu; Hess, Kai-Uwe; Zhang, Youxue; Peslier, Anne; Lange, Rebecca; Dingwell, Donald; Neal, Clive

2016-01-01

It is widely accepted that the Apollo 15 green and Apollo 17 orange glass beads are of volcanic origin. The diffusion profiles of volatiles in these glass beads are believed to be due to degassing during eruption (Saal et al., 2008). The degree of degassing depends on the initial temperature and cooling rate. Therefore, the estimations of volatiles in parental magmas of lunar pyroclastic deposits depend on melt cooling rates. Furthermore, lunar glass beads may have cooled in volcanic environments on the moon. Therefore, the cooling rates may be used to assess the atmospheric condition in an early moon, when volcanic activities were common. The cooling rates of glasses can be inferred from direct heat capacity measurements on the glasses themselves (Wilding et al., 1995, 1996a,b). This method does not require knowledge of glass cooling environments and has been applied to calculate the cooling rates of natural silicate glasses formed in different terrestrial environments. We have carried out heat capacity measurements on hand-picked lunar glass beads using a Netzsch DSC 404C Pegasus differential scanning calorimeter at University of Munich. Our preliminary results suggest that the cooling rate of Apollo 17 orange glass beads may be 12 K/min, based on the correlation between temperature of the heat capacity curve peak in the glass transition range and glass cooling rate. The results imply that the parental magmas of lunar pyroclastic deposits may have contained more water initially than the early estimations (Saal et al., 2008), which used higher cooling rates, 60-180 K/min in the modeling. Furthermore, lunar volcanic glass beads could have been cooled in a hot gaseous medium released from volcanic eruptions, not during free flight. Therefore, our results may shed light on atmospheric condition in an early moon.

Temporal variations in the cooling and denudation history of the Hunza plutonic complex, Karakoram Batholith, revealed by 40Ar/39Ar thermochronology

NASA Astrophysics Data System (ADS)

Krol, Michael A.; Zeitler, Peter K.; Poupeau, GéRard; Pecher, Arnaud

1996-04-01

The 40Ar/39Ar thermochronology of the Late Cretaceous Hunza plutonic complex reveals an episodic cooling and denudation history for this regional-scale pluton. The 40Ar/39Ar analyses of biotites from a vertical relief section of >3200 m reveal a pulse of rapid cooling at ˜20 Ma. In the interval of 110-27 Ma, age-elevation distributions suggest denudation rates of the order of 0.02 ± 0.003 mm/yr. At ˜20 Ma, denudation rates increased significantly to 2.7 ± 0.7 mm/yr, then returned to much slower rates until 12 Ma. A second pulse of rapid cooling beginning at 12 Ma is revealed by inverse numerical modeling of multidiffusion domain alkali feldspars from a vertical section of 1700 m. Decreasing in elevation, these samples record the onset of rapid cooling at 12, 9, and 7 Ma, respectively. All of the alkali feldspars record a period of nearly isothermal conditions prior to the onset of rapid cooling when rates increased to 30°C/m.y. Assuming a geothermal gradient of 30°C/km, these cooling rates translate into denudation rates of 1.0 mm/yr. Apatite fission track analysis indicates denudation rates of 0.7 ± 0.1 mm/yr over the interval of 6.6 Ma to 2.4 Ma in agreement with the alkali feldspar data. These data suggest denudation of 2.9 ± 0.4 km since the Plio-Pleistocene. Together, the alkali feldspar and apatite data indicate that a minimum of 10 km of overburden has been removed since the mid-late Miocene. An electronic supplement of this material may be obtained on a diskette or Anonymous FTP from KOSMOS.AGU.ORG. (LOGIN to AGU's FTP account using ANONYMOUS as the username and GUEST as the password. Go to the right directory by typing CD APEND. Type LS to see what files are available. Type GET and the name of the file to get it. Finally, type EXIT to leave the system).(Paper 95TC02424, Temporal variations in the cooling and denudation history of the Hunza plutonic complex, Karakoram Batholith, revealed by 40Ar/39Ar thermochronology, M.A. Krol, P.K. Zeitler, G

Early Wuchiapingian cooling linked to Emeishan basaltic weathering?

NASA Astrophysics Data System (ADS)

Yang, Jianghai; Cawood, Peter A.; Du, Yuansheng; Condon, Daniel J.; Yan, Jiaxin; Liu, Jianzhong; Huang, Yan; Yuan, Dongxun

2018-06-01

The last glaciation during the late Paleozoic ice age commenced at around the Guadalupian-Lopingian (G-L) boundary and is synchronous with the emplacement of the Emeishan large igneous province. Using CA-TIMS zircon U-Pb dating, we obtained an age of 259.51 ± 0.21 Ma for the uppermost tuff from the Puan volcanic sequence in the eastern Emeishan large igneous province, constraining the timing of Emeishan volcanism and providing another candidate age for the G-L boundary. In addition, we determined an age of 259.69 ± 0.72 Ma for a basal claystone in the immediately overlying Longtan Formation from a drill core section in southwest South China. These ages, along with source weathering trends of mudstones from the lower Longtan Formation, and compiled paleotemperature records, indicate an earliest Wuchiapingian cooling coinciding with the onset of the last Permian glaciation. This global cooling is associated with positive shifts in both organic and carbonate carbon isotopic records and likely a decrease in atmospheric pCO2. A hypothesised causal linkage is proposed in which the rapid post-eruptive basaltic weathering of the Emeishan province in an equatorial humid belt may accelerate the atmospheric CO2 consumption and lead to climate cooling. Our work supports the long-term climate cooling effects of large igneous provinces.

The physics and early history of the intergalactic medium

NASA Astrophysics Data System (ADS)

Barkana, Rennan; Loeb, Abraham

2007-04-01

The intergalactic medium—the cosmic gas that fills the great spaces between the galaxies—is affected by processes ranging from quantum fluctuations in the very early Universe to radiative emission from newly formed stars. This gives the intergalactic medium a dual role as a powerful probe both of fundamental physics and of astrophysics. The heading of fundamental physics includes conditions in the very early Universe and cosmological parameters that determine the age of the Universe and its matter content. The astrophysics refers to chapters of the long cosmic history of stars and galaxies that are being revealed through the effects of stellar feedback on the cosmic gas. This review describes the physics of the intergalactic medium, focusing on recent theoretical and observational developments in understanding early cosmic history. In particular, the earliest generation of stars is thought to have transformed the Universe from darkness to light and to have had an enormous impact on the intergalactic medium. Half a million years after the Big Bang the Universe was filled with atomic hydrogen. As gravity pulled gas clouds together, the first stars ignited and their radiation turned the surrounding atoms back into free electrons and ions. From the observed spectral absorption signatures of the gas between us and distant sources, we know that the process of reionization pervaded most of space a billion years after the Big Bang, so that only a small fraction of the primordial hydrogen atoms remained between galaxies. Knowing exactly when and how the reionization process happened is a primary goal of cosmologists, because this would tell us when the early stars and black holes formed and in what kinds of galaxies. The distribution and clustering of these galaxies is particularly interesting since it is driven by primordial density fluctuations in the dark matter. Cosmic reionization is beginning to be understood with the help of theoretical models and computer

Cool episodes in Early Tertiary Arctic climate: Evidence from Svalbard

NASA Astrophysics Data System (ADS)

Spielhagen, R. F.; Tripati, A.

2009-04-01

The Arctic is a climatically sensitive and important region. However, very little is known about the climatic and oceanographic evolution of the area, particularly prior to the Neogene. Until recently, the Arctic was assumed to be characterized by relatively warm conditions during the early Cenozoic. The Early Tertiary sedimentary sequence on Svalbard contains several layers with coal seams and broad-leaved plants which were commonly accepted as indicators of a generally temperate-warm climate. Here we report on the intermittent occurrence of certain temperature indicators in the succession, which may represent the first northern high-latitude record of near-freezing temperatures for the early Cenozoic. Besides the findings of probably ice-rafted erratic clasts in the Paleocene and Eocene sandstones and shales, we note especially the occurrence of glendonites which are pseudomorphs of calcite after ikaite (calcium carbonate hexahydrate). We measured the chemical composition of Svalbard glendonites which is almost identical to that of similar pseudomorphs from the Lower Cretaceaous of Northern Canada. Mass spectrometric analyses of the glendonite calcite gave very low carbon isotope values. These values suggest a provenance of the calcium carbonate from marine organic carbon and connect our glendonites to the precursor mineral ikaite which has similar low values. Since a variety of studies has demonstrated that ikaite is stable only at temperatures close to freezing point, we have to infer low temperatures also for the deepositional environment of which the sediments were deposited that now hold glendonites. These results imply the occurrence of cooling phases episodically during the warm background climate of the Paleocene and Eocene, suggesting that temperature variability was much greater than previously recognized.

History Of Self-Disclosure In Females And Early Defection From Psychotherapy

ERIC Educational Resources Information Center

Heilbrun, Alfred B., Jr.

1973-01-01

Late adolescent girls who would more likely defect from psychotherapy early had a self-rated history of greater self-disclosure than did girls who would more likely continue. This difference was especially clear with male targets. The second experimental study revealed a similar finding; terminators are higher self-disclosers to males whereas…

Pre-mare cratering and early solar system history

NASA Technical Reports Server (NTRS)

Wetherill, G. W.

1977-01-01

An evaluation of the application of the high extralunar flux in pre-mare times to more general problems of early solar system history is attempted by combining the results of dynamic studies with lunar chronological data. There is a twofold to fourfold contrast in the integral impact flux between the Apollo 14 and 16 sites and the older mare surfaces. This is judged insufficient to account for the contrasting lithology between these two sites: basalts and soil breccias in the maria, annealed breccias and impact melts in the highlands. Therefore, these rocks and their ages (3.9-4.0 b.y.) are thought to predate the surfaces in which they are found. Estimation of the flux needed to produce these lithologies, and difficulties associated with extrapolating this further back in lunar history give support to the "cataclysm" hypothesis of Tera, Papanastassiou, and Wasserburg. Dynamical studies permit separate evaluation of the possible sources for both the "normal" flux during the first 600 million years of lunar history and the "peak" that apparently occurred 4.0 billion years ago. The most likely sources for the normal flux are comets from the vicinity of Uranus and Neptune. The most promising source for the peak is tidal disruption by Earth or Venus of a Ceres-size asteroid initially in a Mars-crossing orbit. Alternative possibilities are suggested.

A brief history of early neuroanesthesia.

PubMed

Chivukula, Srinivas; Grandhi, Ramesh; Friedlander, Robert M

2014-04-01

Two key discoveries in the 19th century--infection control and the development of general anesthesia--provided an impetus for the rapid advancement of surgery, especially within the field of neurosurgery. Improvements in anesthesia and perioperative care, in particular, fostered the development of meticulous surgical technique conducive to the refinement of neuroanatomical understanding and optimization of neurosurgical procedures and outcomes. Yet, even dating back to the earliest times, some form of anesthesia or perioperative pain management was used during neurosurgical procedures. Despite a few reports on anesthesia published around the time of William Morton's now-famous public demonstration of ether anesthesia in 1846, relatively little is known or written of early anesthetics in neurosurgery. In the present article the authors discuss the history of anesthesia pertaining to neurosurgical procedures and draw parallels between the refinements and developments in anesthesia care over time with some of the concomitant advances in neurosurgery.

An early history of human breast cancer: West meets East.

PubMed

Yan, Shou-He

2013-09-01

Cancer has been increasingly recognized as a global issue. This is especially true in countries like China, where cancer incidence has increased likely because of changes in environment and lifestyle. However, cancer is not a modern disease; early cases have been recorded in ancient medical books in the West and in China. Here, we provide a brief history of cancer, focusing on cancer of the breast, and review the etymology of ai, the Chinese character for cancer. Notable findings from both Western and Chinese traditional medicine are presented to give an overview of the most important, early contributors to our evolving understanding of human breast cancer. We also discuss the earliest historical documents to record patients with breast cancer.

Los Angeles-Long Beach Harbor Areas Prehistory and Early History, Los Angeles County, California,

DTIC Science & Technology

1978-04-01

H - R136 656 LOS ANGELES-LONG BEACH HARBOR ARE AS PREHISTORY AND I/i EARLY HISTORY LO S ANGELES COUNTY CALIFORNIA(U) ARMY ENGINEER DISTRICT LOS...world. The The Early Systems Period (50,000? to 7,000 creation of this megalopolis, unfortunately, years ago) had severe impacts on the natural...called amino acid dating. Using this of early occupation. There is data which system , archeologists determined that human suggests that some of the

Workshop on Pristine Highlands Rocks and the early History of the Moon

NASA Technical Reports Server (NTRS)

Longhi, J. (Editor); Ryder, G. (Editor)

1983-01-01

Oxide composition of the Moon, evidence for an initially totally molten Moon, geophysical contraints on lunar composition, random sampling of a layered intrusion, lunar highland rocks, early evolution of the Moon, mineralogy and petrology of the pristine rocks, relationship of the pristine nonmore rocks to the highlands soils and breccias, ferroan anorthositic norite, early lunar igneous history, compositional variation in ferroan anosthosites, a lunar magma ocean, deposits of lunar pristine rocks, lunar and planetary compositions and early fractionation in the solar nebula, Moon composition models, petrogenesis in a Moon with a chondritic refractory lithophile pattern, a terrestrial analog of lunar ilmenite bearing camulates, and the lunar magma ocean are summarized.

The early Barremian warm pulse and the late Barremian cooling: a high resolution geochemical record of the Boreal Realm

NASA Astrophysics Data System (ADS)

Mutterlose, J.; Malkoc, M.

2009-04-01

A high resolution geochemical study of seven Barremian (lower Cretaceous) sections in NW Europe documents warming and cooling periods throughout the investigated interval. A total of 289 belemnite guards from localities in NE England and NW Germany were analysed for their trace elements (Mg, Sr, Fe and Mn) and their stable isotope composition (δ13C, δ18O) in order to reconstruct the palaeotemperature record and to better understand different palaeotemperature proxies (δ18O, Mg/Ca). The material has been collected bed-by-bed from bio- and lithostratigraphically well studied outcrops with a palaeolatitude of 36-38°N. The carbon isotope curve of the Barremian is described by a long term (5my) increase from 1‰ in the early Barremian to 3‰ in the late Barremian. This long term trend is thought to reflect the global signal of the carbon budget of the Barremian oceans. Superimposed on this signature is a short termed peak (~ 105kyrs) of 2.5‰ in the late early Barremian Aulacoteuthis zone. This "Aulacoteuthis peak", which goes along with the widespread deposition of TOC rich mudstones, was caused by increased productivity. It is seen as a regional signal related to warm-humid conditions and palaeoceanographically a quasi lagoonal setting. δ13C shifts of 1.5‰ from specimens collected from one horizon may reflect high resolution seasonal changes of run-off and nutrient supply. The oxygen isotope signature clearly shows similar palaeotemperature variations of the approx. 5my lasting Barremian for all sections investigated. The climatic evolution allows to recognize three different phases. An earliest Barremian cool phase (Praeoxyteuthis pugio zone) is characterized by δ18O values of - 1.2‰ to 0.3‰ (16°C to 10°C) with most data plotting around - 0.2‰ (12°C). This "P. pugio cool phase", which extends into the underlying Hauterivian, is followed by a distinctive warming event in the late early Barremian Aulacoteuthis zone. This "Aulacoteuthis warm pulse

Cooling History and Redox State of NWA 8694 Chassignite: Comparison with Chassigny and NWA 2737

NASA Technical Reports Server (NTRS)

Mikouchi, T.; Takenouchi, A.; Zolensky, M. E.

2016-01-01

NWA 8694 is a new chassignite whose constituent minerals are more Fe-rich than those in the other known chassignites (Chassigny and NWA 2737), and may suggest a petrogenetic relationship to nakhlites. In this abstract we report mineralogy of NWA 8694 to infer its cooling rate and redox state, and discuss its thermal and shock history in comparison with other chassignites. NWA 8694 is a cumulate dunite of approximately 2 mm olivine with interstitial pyroxene and feldspar. Olivine is homogeneous (Fo(sub 55-56)), but Ca decreases at the approximately 50-100 micrometer rim (0.25-0.1 wt% CaO). Because the Ca-depleted rim is narrower than those in other chassignites (approximately 50 ?micrometer), NWA 8694 may have cooled slightly faster than the others (approximately 30 C/yr), but would be in the same order. Pyroxenes are low- and high-Ca pyroxenes, both exhibiting sub-micron exsolution textures (0.2-0.3 micrometer wide lamellae with the spacing of 0.8-1.8 micrometers). Although the low-Ca pyroxene host has an orthopyroxene composition (Wo approximately 2), the EBSD analysis suggests a pigeonite structure (P2(sub 1)/c), which is also reported from the Chassigny pyroxene. The size of exsolution texture is a bit smaller, but broadly similar to those in other chassignites, implying a similar fast cooling rate (35-43 C/yr). Feldspars are isotropic (plagioclase: clustered around An25Or10, K-feldspar: approximately An19Or78), suggestive of extensive shock metamorphism, consistent with undulatory extinction of olivine. Feldspar compositions are around the equilibrium isotherm of approximately 800 C. The olivine and chromite compositions give an equilibration temperature of 760-810 C and logfO2 of QFM+/-0.3. The inferred fast cooling rate and high fO2 of NWA 8694 are both similar to those of Chassigny and NWA 2737, and suggest a common formation condition (e.g., thick lava flow or shallow intrusion) under oxidizing condition. The Fe-rich mineral compositions of NWA 8694 may be

Cretaceous–Cenozoic burial and exhumation history of the Chukchi shelf, offshore Arctic Alaska

USGS Publications Warehouse

Craddock, William H.; Houseknecht, David W.

2016-01-01

Apatite fission track (AFT) and vitrinite reflectance data from five exploration wells and three seafloor cores illuminate the thermal history of the underexplored United States Chukchi shelf. On the northeastern shelf, Triassic strata in the Chevron 1 Diamond well record apatite annealing followed by cooling, possibly during the Triassic to Middle Jurassic, which is a thermal history likely related to Canada Basin rifting. Jurassic strata exhumed in the hanging wall of the frontal Herald Arch thrust fault record a history of probable Late Jurassic to Early Cretaceous structural burial in the Chukotka fold and thrust belt, followed by rapid exhumation to near-surface temperatures at 104 ± 30 Ma. This history of contractional tectonism is in good agreement with inherited fission track ages in low-thermal-maturity, Cretaceous–Cenozoic strata in the Chukchi foreland, providing complementary evidence for the timing of exhumation and suggesting a source-to-sink relationship. In the central Chukchi foreland, inverse modeling of reset AFT samples from the Shell 1 Klondike and Shell 1 Crackerjack wells reveals several tens of degrees of cooling from maximum paleo-temperatures, with maximum heating permissible at any time from about 100 to 50 Ma, and cooling persisting to as recent as 30 Ma. Similar histories are compatible with partially reset AFT samples from other Chukchi wells (Shell 1 Popcorn, Shell 1 Burger, and Chevron 1 Diamond) and are probable in light of regional geologic evidence. Given geologic context provided by regional seismic reflection data, we interpret these inverse models to reveal a Late Cretaceous episode of cyclical burial and erosion across the central Chukchi shelf, possibly partially overprinted by Cenozoic cooling related to decreasing surface temperatures. Regionally, we interpret this kinematic history to be reflective of moderate, transpressional deformation of the Chukchi shelf during the final phases of contractional tectonism in the

Magnetic grain-size variations through an ash flow sheet: influence on magnetic properties and implications for cooling history

USGS Publications Warehouse

Rosenbaum, J.G.

1993-01-01

Rock magnetic studies of tuffs are essential to the interpretation of paleomagnetic data derived from such rocks, provide a basis for interpretation of aeromagnetic data over volcanic terranes, and yield insights into the depositional and cooling histories of ash flow sheets. A rhyolitic ash flow sheet, the Miocene-aged Tiva Canyon Member of the Paintbrush Tuff, contains both titanomagnetite phenocrysts, present in the magma prior to eruption, and cubic Fe-oxide microcrystals that grew after emplacement. Systematic variations in the quantity and magnetic grain size of the microcrystals produce large variations in magnetic properties through a section of the ash flow sheet penetrated in a borehole on the Nevada Test Site. Microcrystals are important contributors to remanent magnetization and magnetic susceptibility in two 15-m-thick zones at the top and bottom. Within these zones the size of microcrystals decreases both toward the quenched margins and toward the interior of the sheet. The decrease in microcrystal size toward the interior of the sheet is interpreted to indicate the presence of a cooling break; possibly represented by a concentration of pumice. -from Author

Geminga: A cooling superfluid neutron star

NASA Technical Reports Server (NTRS)

Page, Dany

1994-01-01

We compare the recent temperature estimate for Geminga with neutron star cooling models. Because of its age (approximately 3.4 x 10(exp 5) yr), Geminga is in the photon cooling era. We show that its surface temperature (approximately 5.2 x 10(exp 5) K) can be understood by both types of neutrino cooling scenarios, i.e., slow neutrino cooling by the modified Urca process or fast neutrino cooling by the direct Urca process or by some exotic matter, and thus does not allow us to discriminate between these two competing schemes. However, for both types of scenarios, agreement with the observed temperature can only be obtained if baryon pairing is present in most, if not all, of the core of the star. Within the slow neutrino cooling scenario, early neutrino cooling is not sufficient to explain the observed low temperature, and extensive pairing in the core is necessary to reduce the specific heat and increase the cooling rate in the present photon cooling era. Within all the fast neutrino cooling scenarios, pairing is necessary throughout the whole core to control the enormous early neutrino emission which, without pairing suppression, would result in a surface temperature at the present time much lower than observed. We also comment on the recent temperature estimates for PSR 0656+14 and PSR 1055-52, which pertain to the same photon cooling era. If one assumes that all neutron stars undergo fast neutrino cooling, then these two objects also provide evidence for extensive baryon pairing in their core; but observational uncertainties also permit a more conservative interpretation, with slow neutrino emission and no pairing at all. We argue though that observational evidence for the slow neutrino cooling model (the 'standard' model) is in fact very dim and that the interpretation of the surface temperature of all neutron stars could be done with a reasonable theoretical a priori within the fast neutrino cooling scenarios only. In this case, Geminga, PSR 0656+14, and PSR

The Cool Little Kids randomised controlled trial: population-level early prevention for anxiety disorders.

PubMed

Bayer, Jordana K; Rapee, Ronald M; Hiscock, Harriet; Ukoumunne, Obioha C; Mihalopoulos, Cathrine; Clifford, Susan; Wake, Melissa

2011-01-05

The World Health Organization predicts that by 2030 internalising problems (e.g. depression and anxiety) will be second only to HIV/AIDS in international burden of disease. Internalising problems affect 1 in 7 school aged children, impacting on peer relations, school engagement, and later mental health, relationships and employment. The development of early childhood prevention for internalising problems is in its infancy. The current study follows two successful 'efficacy' trials of a parenting group intervention to reduce internalising disorders in temperamentally inhibited preschool children. Cool Little Kids is a population-level randomised trial to determine the impacts of systematically screening preschoolers for inhibition then offering a parenting group intervention, on child internalising problems and economic costs at school entry. This randomised trial will be conducted within the preschool service system, attended by more than 95% of Australian children in the year before starting school. In early 2011, preschool services in four local government areas in Melbourne, Australia, will distribute the screening tool. The ≈16% (n≈500) with temperamental inhibition will enter the trial. Intervention parents will be offered Cool Little Kids, a 6-session group program in the local community, focusing on ways to develop their child's bravery skills by reducing overprotective parenting interactions. Outcomes one and two years post-baseline will comprise child internalising diagnoses and symptoms, parenting interactions, and parent wellbeing. An economic evaluation (cost-consequences framework) will compare incremental differences in costs of the intervention versus control children to incremental differences in outcomes, from a societal perspective. Analyses will use the intention-to-treat principle, using logistic and linear regression models (binary and continuous outcomes respectively) to compare outcomes between the trial arms. This trial addresses gaps

Early type galaxies: Mapping out the two-dimensional space of galaxy star formation histories

NASA Astrophysics Data System (ADS)

Graves, Genevieve J.

Early type galaxies form a multi-parameter family, as evidenced by the two- dimensional (2-D) Fundamental Plane relationship. However, their star formation histories are often treated as a one-dimensional mass sequence. This dissertation presents a systematic study of the relationship between the multi- parameter structural properties of early type galaxies and their star formation histoires. We demonstrate that the stellar populations of early type galaxies span a 2-D space, which means that their star formation histories form a two- parameter family. This 2-D family is then mapped onto several familiar early type galaxy scaling relations, including the color-magnitude relation, the Fundamental Plane, and a cross-section through the Fundamental Plane. We find that the stellar population properties, and therefore the star formation histories of early type galaxies depend most strongly on galaxy velocity dispersion (s), rather than on luminosity ( L ), stellar mass ( M [low *] ), or dynamical mass ( M dyn ). Interestingly, stellar populations are independent of the radius ( R e ) of the galaxies. At fixed s, they show correlated residuals through the thickness of the Fundamental Plane (FP) in the surface-brightness ( I e ) dimension, such that low-surface-brightness galaxies are older, less metal-enriched, and more enhanced in Mg relative to Fe than their counterparts at the same s and R e on the FP midplane. Similarly, high- surface-brightness galaxies are younger, more metal-rich, and less Mg-enhanced than their counterparts on the FP midplane. These differences suggest that the duration of star formation varies through the thickness of the FP. If the dynamical mass-to-light ratios of early type galaxies ( M dyn /L ) were constant for all such galaxies, the FP would be equivalent to the plane predicted by the virial relation. However, the observed FP does not exactly match the virial plane. The FP is tilted from the virial plane, indicating that M dyn /L varies

Family history of skin cancer is associated with early-onset basal cell carcinoma independent of MC1R genotype.

PubMed

Berlin, Nicholas L; Cartmel, Brenda; Leffell, David J; Bale, Allen E; Mayne, Susan T; Ferrucci, Leah M

2015-12-01

As a marker of genetic susceptibility and shared lifestyle characteristics, family history of cancer is often used to evaluate an individual's risk for developing a particular malignancy. With comprehensive data on pigment characteristics, lifestyle factors, and melanocortin 1 receptor (MC1R) gene sequence, we sought to clarify the role of family history of skin cancer in early-onset basal cell carcinoma (BCC). Early onset BCC cases (n=376) and controls with benign skin conditions (n=383) under age 40 were identified through Yale dermatopathology. Self-report data on family history of skin cancer (melanoma and non-melanoma skin cancer), including age of onset in relatives, was available from a structured interview. Participants also provided saliva samples for sequencing of MC1R. A family history of skin cancer was associated with an increased risk of early-onset BCC (OR 2.49, 95% CI 1.80-3.45). In multivariate models, family history remained a strong risk factor for early-onset BCC after adjustment for pigment characteristics, UV exposure, and MC1R genotype (OR 2.41, 95% CI 1.74-3.35). Risk for BCC varied based upon the type and age of onset of skin cancer among affected relatives; individuals with a first-degree relative diagnosed with skin cancer prior to age 50 were at highest risk for BCC (OR 4.79, 95% CI 2.90-7.90). Even after taking into account potential confounding effects of MC1R genotype and various lifestyle factors that close relatives may share, family history of skin cancer remained strongly associated with early-onset BCC. Copyright © 2015. Published by Elsevier Ltd.

Early Childhood Education and Care for Native Hawaiian Children in Hawai'i: A Brief History

ERIC Educational Resources Information Center

Grace, Donna J.; Ku'ulei Serna, Alethea

2013-01-01

This study provides a brief overview of the history of early childhood education and care for Native Hawaiian children in Hawai'i. Data sources include a literature review, examination of archival documents, and interviews with a sample of Native Hawaiian parents and community members. We trace the emergence of outside-the-home early childhood…

Crystallization history of lunar picritic basalt sample 12002 - Phase-equilibria and cooling-rate studies

NASA Technical Reports Server (NTRS)

Walker, D.; Kirkpatrick, R. J.; Longhi, J.; Hays, J. F.

1976-01-01

Experimental crystallization of a lunar picrite composition (sample 12002) at controlled linear cooling rates produces systematic changes in the temperature at which crystalline phases appear, in the texture, and in crystal morphology as a function of cooling rate. Phases crystallize in the order olivine, chromium spinel, pyroxene, plagioclase, and ilmenite during equilibrium crystallization, but ilmenite and plagioclase reverse their order of appearance and silica crystallizes in the groundmass during controlled cooling experiments. The partition of iron and magnesium between olivine and liquid is independent of cooling rate, temperature, and pressure. Comparison of the olivine nucleation densities in the lunar sample and in the experiments indicates that the sample began cooling at about 1 deg C/hr. Pyroxene size, chemistry, and growth instability spacings, as well as groundmass coarseness, all suggest that the cooling rate subsequently decreased by as much as a factor of 10 or more. The porphyritic texture of this sample, then, is produced at a decreasing, rather than a discontinuously increasing, cooling rate.

Cooling rates for glass containing lunar compositions

NASA Technical Reports Server (NTRS)

Fang, C. Y.; Yinnon, H.; Uhlmann, D. R.

1983-01-01

Cooling rates required to form glassy or partly-crystalline bodies of 14 lunar compositions have been estimated using a previously introduced, simplified model. The calculated cooling rates are found to be in good agreement with cooling rates measured for the same compositions. Measurements are also reported of the liquidus temperature and glass transition temperature for each composition. Inferred cooling rates are combined with heat flow analyses to obtain insight into the thermal histories of samples 15422, 14162, 15025, 74220, 74241, 10084, 15425, and 15427. The critical cooling rates required to form glasses of 24 lunar compositions, including the 14 compositions of the present study, are suggested to increase systematically with increasing ratio of total network modifiers/total network formers in the compositions. This reflects the importance of melt viscosity in affecting glass formation.

Constraints on early events in Martian history as derived from the cratering record

NASA Technical Reports Server (NTRS)

Barlow, Nadine G.

1990-01-01

Constrains on early events in Martian history are derived using the planet's cratering record. Variations in the shapes of the crater size-frequency distribution curves are interpreted as indicative of the size-frequency distribution of the production populations, thus providing information about the age of the unit relative to the end of the heavy bombardment period. Results from the analysis of craters superposed on heavily cratered units across the Martian surface provide constraints on the hemispheric dichotomy and the early erosional conditions on Mars.

The quantum defect: Early history and recent developments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rau, A.R.; Inokuti, M.

1997-03-01

The notion of the quantum defect is important in atomic and molecular spectroscopy and also in unifying spectroscopy with collision theory. In the latter context, the quantum defect may be viewed as an ancestor of the phase shift. However, the origin of the term {open_quotes}quantum defect{close_quotes} does not seem to be explained in standard textbooks. It occurred in a 1921 paper by Schr{umlt o}dinger, preceding quantum mechanics, yet giving the correct meaning as an index of the short-range interactions with the core of an atom. We present the early history of the quantum-defect idea, and sketch its recent developments. {copyright}more » {ital 1997 American Association of Physics Teachers.}« less

Evidence From Svalbard for Cool Episodes in Early Tertiary Arctic Climate

NASA Astrophysics Data System (ADS)

Spielhagen, R. F.; Tripati, A.; Mac Niocaill, C.

2008-12-01

The Arctic is a climatically sensitive and important region. However, very little is known about the climatic and oceanographic evolution of the area, particularly prior to the Neogene. Until recently, the Arctic was assumed to be characterized by relatively warm conditions during the early Cenozoic. The Early Tertiary sedimentary sequence on Svalbard contains several layers with coal seams and broad-leaved plants which were commonly accepted as indicators of a generally temperate-warm climate. Here we report on the intermittent occurrence of certain temperature indicators in the succession, which may represent the first northern high- latitude record of near-freezing temperatures for the early Cenozoic. Besides the findings of probably ice- rafted erratic clasts in the Paleocene and Eocene sandstones and shales, we note especially the occurrence of glendonites which are pseudomorphs of calcite after ikaite (calcium carbonate hexahydrate). Stratigraphic control for the most important glendonite layers was improved by paleomagnetic investigations on the host sediment. We measured the chemical composition of Svalbard glendonites which is almost identical to that of similar pseudomorphs from the Lower Cretaceaous of Northern Canada. Mass spectrometric analyses of the glendonite calcite gave very low carbon isotope values. These values suggest a provenance of the calcium carbonate from marine organic carbon and connect our glendonites to the precursor mineral ikaite which has similar low values. Since a variety of studies has demonstrated that ikaite is stable only at temperatures close to freezing point, we have to infer low temperatures also for the deepositional environment of which the sediments were deposited that now hold glendonites. These results imply the occurrence of cooling phases episodically during the warm background climate of the Paleocene and Eocene, suggesting that temperature variability was much greater than previously recognized.

Outcomes of patients with a pretransplant history of early-stage melanoma.

PubMed

Puza, Charles J; Barbas, Andrew S; Mosca, Paul J

2018-06-25

A history of melanoma within the preceding 5 years is commonly considered a contraindication to solid organ transplantation. We investigated how a pretransplant history of melanoma impacts patient survival and melanoma recurrence. Institutional Review Board approval was obtained, and Duke's retrospective database was used to identify 4552 patients who underwent a solid organ transplant at Duke University from 1 January 2001 to 31 December 2016. Data with regard to the transplant, melanoma characteristics, rejection episodes, and survival were recorded. Of 4552 patients who underwent a solid organ transplant, 12 (0.3%) had a history of melanoma before transplant (six with melanoma in situ and six with stage I disease). The median time between melanoma diagnosis and transplant was 4.13 years (range: 1.1-13.3 years). The study cohort consisted of four liver transplants, four lung transplants, one kidney transplant, one heart transplant, one small bowel transplant, and one multivisceral transplant. At the median follow-up time of 2.8 years, 10 (83.3%) patients were alive. In nonmelanoma cohorts, the 3-year survival is 70% for thoracic transplants, 78% for liver transplants, and 88% for kidney transplants. In well-selected patients with a history of early-stage melanoma and an appropriate time interval between melanoma treatment and transplant, post-transplant outcomes are favorable.

Continental emergence and growth on a cooling earth

NASA Astrophysics Data System (ADS)

Vlaar, N. J.

2000-07-01

Isostasy considerations are connected to a 1-D model of mantle differentiation due to pressure release partial melting to obtain a model for the evolution of the relative sea level with respect to the continent during the earth secular cooling. In this context, a new mechanism is derived for the selective exhumation of exposed ancient cratons. The model results in a quantitative scenario for sea-level fall due to the changing thicknesses of the oceanic basaltic crust and its harzburgite residual layer as a function of falling mantle temperature. It is also shown that the buoyancy of the harzburgite root of a stabilized continental craton has an important effect on sea-level and on the isostatic readjustment and exhumation of exposed continental surface during the earth's secular cooling. The model does not depend on the usual assumption of constant continental freeboard and crustal thickness and its application is not restricted to the post-Archaean. It predicts large-scale continental emergence near the end of the Archaean and the early Proterozoic. This provides an explanation for reported late Archaean emergence and the subsequent formation of late Archaean cratonic platforms and early Proterozoic sedimentary basins. For a period of secular cooling of 3.8 Ga, corresponding to the length of the geological record, the model predicts a fall of the ocean floor of some 4 km or more. For a constant ocean depth, this implies a sea-level fall of the same magnitude. A formula is derived that allows for an increasing ocean depth due to either the changing ratio of continental with respect to oceanic area, or to a possible increase of the oceanic volume during the geological history. Increasing ocean depth results in a later emergence of submarine ancient geological formations compared to the case when ocean depth is constant. Selective exhumation is studied for the case of constant ocean depth. It is shown that for this case, early exposed continental crust can be exhumed

Early parental loss and depression history: associations with recent life stress in major depressive disorder.

PubMed

Slavich, George M; Monroe, Scott M; Gotlib, Ian H

2011-09-01

Although exposure to early adversity and prior experiences with depression have both been associated with lower levels of precipitating life stress in depression, it is unclear whether these stress sensitization effects are similar for all types of stress or whether they are specific to stressors that may be particularly depressogenic, such as those involving interpersonal loss. To investigate this issue, we administered structured, interview-based measures of early adversity, depression history, and recent life stress to one hundred adults who were diagnosed with major depressive disorder. As predicted, individuals who experienced early parental loss or prolonged separation (i.e., lasting one year or longer) and persons with more lifetime episodes of depression became depressed following lower levels of life stress occurring in the etiologically-central time period of three months prior to onset of depression. Importantly, however, additional analyses revealed that these effects were unique to stressors involving interpersonal loss. These data highlight potential stressor-specific effects in stress sensitization and demonstrate for the first time that individuals exposed to early parental loss or separation, and persons with greater histories of MDD, may be selectively sensitized to stressors involving interpersonal loss. Copyright © 2011 Elsevier Ltd. All rights reserved.

Complex Cooling Histories of Lunar Troctolite 76535 and Stillwater Orthoyroxenite SC-936

NASA Technical Reports Server (NTRS)

Domeneghetti, M. Chiara; McCallum, I. S.; Schwartz, J. M.; Camara, F.; Zema, M.; McCammon, C.; Ganguly, J.

2001-01-01

Fe-Mg site occupancy determinations of orthopyroxene from troctolite 76535 yield closure temperatures of ordering of 500-550 C and cooling rates of 1-10 C per year corresponding to shallow burial. 76535 was excavated from deep lunar crust before it had cooled to approx. 550 C. Additional information is contained in the original extended abstract.

Do Children with Better Inhibitory Control Donate More? Differentiating between Early and Middle Childhood and Cool and Hot Inhibitory Control.

PubMed

Hao, Jian

2017-01-01

Inhibitory control may play an important part in prosocial behavior, such as donating behavior. However, it is not clear at what developmental stage inhibitory control becomes associated with donating behavior and which aspects of inhibitory control are related to donating behavior during development in early to middle childhood. The present study aimed to clarify these issues with two experiments. In Experiment 1, 103 3- to 5-year-old preschoolers completed cool (Stroop-like) and hot (delay of gratification) inhibitory control tasks and a donating task. The results indicated that there were no relationships between cool or hot inhibitory control and donating behavior in the whole group and each age group of the preschoolers. In Experiment 2, 140 elementary school children in Grades 2, 4, and 6 completed cool (Stroop-like) and hot (delay of gratification) inhibitory control tasks and a donating task. The results showed that inhibitory control was positively associated with donating behavior in the whole group. Cool and hot inhibitory control respectively predicted donating behavior in the second and sixth graders. Therefore, the present study reveals that donating behavior increasingly relies on specific inhibitory control, i.e., hot inhibitory control as children grow in middle childhood.

Highly ionized atoms in cooling gas. [in model for cooling of hot Galactic corona

NASA Technical Reports Server (NTRS)

Edgar, Richard J.; Chevalier, Roger A.

1986-01-01

The ionization of low density gas cooling from a high temperature was calculated. The evolution during the cooling is assumed to be isochoric, isobaric, or a combination of these cases. The calculations are used to predict the column densities and ultraviolet line luminosities of highly ionized atoms in cooling gas. In a model for cooling of a hot galactic corona, it is shown that the observed value of N(N V) can be produced in the cooling gas, while the predicted value of N(Si IV) falls short of the observed value by a factor of about 5. The same model predicts fluxes of ultraviolet emission lines that are a factor of 10 lower than the claimed detections of Feldman, Bruna, and Henry. Predictions are made for ultraviolet lines in cooling flows in early-type galaxies and clusters of galaxies. It is shown that the column densities of interest vary over a fairly narrow range, while the emission line luminosities are simply proportional to the mass inflow rate.

The Cool Little Kids randomised controlled trial: Population-level early prevention for anxiety disorders

PubMed Central

2011-01-01

Background The World Health Organization predicts that by 2030 internalising problems (e.g. depression and anxiety) will be second only to HIV/AIDS in international burden of disease. Internalising problems affect 1 in 7 school aged children, impacting on peer relations, school engagement, and later mental health, relationships and employment. The development of early childhood prevention for internalising problems is in its infancy. The current study follows two successful 'efficacy' trials of a parenting group intervention to reduce internalising disorders in temperamentally inhibited preschool children. Cool Little Kids is a population-level randomised trial to determine the impacts of systematically screening preschoolers for inhibition then offering a parenting group intervention, on child internalising problems and economic costs at school entry. Methods/Design This randomised trial will be conducted within the preschool service system, attended by more than 95% of Australian children in the year before starting school. In early 2011, preschool services in four local government areas in Melbourne, Australia, will distribute the screening tool. The ≈16% (n≈500) with temperamental inhibition will enter the trial. Intervention parents will be offered Cool Little Kids, a 6-session group program in the local community, focusing on ways to develop their child's bravery skills by reducing overprotective parenting interactions. Outcomes one and two years post-baseline will comprise child internalising diagnoses and symptoms, parenting interactions, and parent wellbeing. An economic evaluation (cost-consequences framework) will compare incremental differences in costs of the intervention versus control children to incremental differences in outcomes, from a societal perspective. Analyses will use the intention-to-treat principle, using logistic and linear regression models (binary and continuous outcomes respectively) to compare outcomes between the trial arms

Tidal friction and the early history of the moon's orbit

NASA Technical Reports Server (NTRS)

Rubincam, D. P.

1975-01-01

The present work investigates the consequences implied by various rheological models of the early earth for the orbital history of the moon subsequent to its formation. Models of the earth that yield small tidal angles, such as low-viscosity models, imply that the moon never orbited in the earth's equatorial plane, thereby ruling out an equatorial origin for the moon. A high-viscosity model is shown to permit the moon to originate in the equatorial plane and still account for the present-day characteristics of the moon's orbit.

Social Confidence in Early Adulthood among Young People with and without a History of Language Impairment

ERIC Educational Resources Information Center

Durkin, Kevin; Toseeb, Umar; Botting, Nicola; Pickles, Andrew; Conti-Ramsden, Gina

2017-01-01

Purpose: The purposes of this study were to test the predictions that lower self-esteem and higher shyness in individuals with a history of language impairment (LI) would continue from adolescence into early adulthood and that those with LI would have lower social self-efficacy in early adulthood. Method: Participants were young people with a…

The early history of the synapse: from Plato to Sherrington.

PubMed

Bennett, M R

1999-09-15

One hundred years ago, in 1897, Sherrington adopted the name synapse. However, the concept of the synapse emerged from considerations of how muscles are contracted and so locomotion affected over a period of 2400 years, from the time of Plato and Aristotle in the 4th century BC to the early part of the 20th century. This early history is considered in the present review. In terms of duration of influence, the early history was dominated by Aristotle's concept of vital pneuma. This was derived from the ether which filled all space, taken in by the lungs, transformed to vital pneuma in the heart, and then conducted in the blood stream to be transmitted to muscles. The vital pneuma then initiated the final phase of the muscle's psyche, that is, its contraction leading to locomotion. Aristotle's ideas had to be modified with the discovery by Galen and his students in the 2nd and 3rd centuries AD that nerves arising from the brain and spinal cord are necessary for the initiation of muscle contraction. They modified the Aristotlean account so that the vital pneuma delivered by blood vessels to the brain was converted there to psychic pneuma, from whence it was conducted along nerves to be transmitted to muscle, so allowing the muscle to contract. There matters rested for about 1300 years until Descartes. Descartes rejected the idea of organs and muscles possessing a psyche with a final cause that was released by the conduction and transmission of psychic pneuma in nerves, emphasising that mechanical explanations must be sought when determining the function of an organ or muscle. He argued in his corpuscular theory that fine particles derived from the blood in the brain, which he gave the unfortunate name of animal spirits, were conducted and transmitted along nerves to enter muscle during transmission, so leading to the increase in width of the muscle fibres, their shortening and contraction. This description was elaborated on in great detail by Descartes, and by his

Late Quaternary glaciation history of monsoon-dominated Dingad basin, central Himalaya, India

NASA Astrophysics Data System (ADS)

Shukla, Tanuj; Mehta, Manish; Jaiswal, Manoj K.; Srivastava, Pradeep; Dobhal, D. P.; Nainwal, H. C.; Singh, Atul K.

2018-02-01

The study presents the Late Quaternary glaciation history of monsoon-dominated Dokriani Glacier valley, Dingad basin, central Himalaya, India. The basin is tested for the mechanism of landforms preservation in high relief and abundant precipitation regimes of the Higher Himalaya. Field geomorphology and remote sensing data, supported by Optical Stimulated Luminescence (OSL) dating enabled identification of five major glacial events of decreasing magnitude. The oldest glacial stage, Dokriani Glacial Stage I (DGS-I), extended down to ∼8 km (2883 m asl) from present-day snout (3965 m asl) followed by other four glaciations events viz. DGS-II, DGS-III, DGS-IV and DGS-V terminating at ∼3211, 3445, 3648 and ∼3733 m asl respectively. The DGS-I glaciation (∼25-∼22 ka BP) occurred during early Marine Isotope Stage (MIS) -2, characterized as Last Glacial Maximum (LGM) extension of the valley. Similarly, DGS-II stage (∼14-∼11 ka BP) represents the global cool and dry Older Dryas and Younger Dryas event glaciation. The DGS-III glaciation (∼8 ka BP) coincides with early Holocene 8.2 ka cooling event, the DGS-IV glaciations (∼4-3.7 ka BP) corresponds to 4.2 ka cool and drier event, DGS-V (∼2.7-∼1 ka BP) represents the cool and moist late Holocene glacial advancement of the valley. This study suggests that the Dokriani Glacier valley responded to the global lowering of temperature and variable precipitation conditions. This study also highlights the close correlation between the monsoon-dominated valley glaciations and Northern Hemisphere cooling events influenced by North Atlantic climate.

Post-rift Tectonic History of the Songliao Basin, NE China: Cooling Events and Post-rift Unconformities Driven by Orogenic Pulses From Plate Boundaries

NASA Astrophysics Data System (ADS)

Song, Ying; Stepashko, Andrei; Liu, Keyu; He, Qingkun; Shen, Chuanbo; Shi, Bingjie; Ren, Jianye

2018-03-01

The classic lithosphere-stretching model predicts that the post-rift evolution of extensional basin should be exclusively controlled by decaying thermal subsidence. However, the stratigraphy of the Songliao Basin in northeastern China shows that the post-rift evolution was punctuated by multiple episodes of uplift and exhumation events, commonly attributed to the response to regional tectonic events, including the far-field compression from plate margins. Three prominent tectonostratigraphic post-rift unconformities are recognized in the Late Cretaceous strata of the basin: T11, T03, and T02. The subsequent Cenozoic history is less constrained due to the incomplete record of younger deposits. In this paper, we utilize detrital apatite fission track (AFT) thermochronology to unravel the enigmatic timing and origin of post-rift unconformities. Relating the AFT results to the unconformities and other geological data, we conclude that in the post-rift stage, the basin experienced a multiepisodic tectonic evolution with four distinct cooling and exhumation events. The thermal history and age pattern document the timing of the unconformities in the Cretaceous succession: the T11 unconformity at 88-86 Ma, the T03 unconformity at 79-75 Ma, and the T02 unconformity at 65-50 Ma. A previously unrecognized Oligocene unconformity is also defined by a 32-24 Ma cooling event. Tectonically, all the cooling episodes were regional, controlled by plate boundary stresses. We propose that Pacific dynamics influenced the wider part of eastern Asia during the Late Cretaceous until Cenozoic, whereas the far-field effects of the Neo-Tethys subduction and collision processes became another tectonic driver in the later Cenozoic.

Impact melting early in lunar history

NASA Technical Reports Server (NTRS)

Lange, M. A.; Ahrens, T. J.

1979-01-01

The total amount of impact melt produced during early lunar history is examined in light of theoretically and experimentally determined relations between crater diameter (D) and impact melt volume. The time dependence of the melt production is given by the time dependent impact rate as derived from cratering statistics for two different crater-size classes. Results show that small scale cratering (D less than or equal to 30 km) leads to melt volumes which fit selected observations specifying the amount of impact melt contained in the lunar regolith and in craters with diameters less than 10 km. Larger craters (D greater than 30 km) are capable of forming the abundant impact melt breccias found on the lunar surface. The group of large craters (D greater than 30 km) produces nearly 10 times as much impact melt as all the smaller craters, and thus, the large impacts dominate the modification of the lunar surface. A contradiction between the distribution of radiometric rock ages and a model of exponentially decreasing cratering rate going back to 4.5 b.y. is reflected in uncertainty in the distribution of impact melt as a function of time on the moon.

Surgical management of early pregnancy failure: history, politics, and safe, cost-effective care.

PubMed

Harris, Lisa H; Dalton, Vanessa K; Johnson, Timothy R B

2007-05-01

Early pregnancy failure and induced abortion are often managed differently, even though safe uterine evacuation is the goal in both. Early pregnancy failure is commonly treated by curettage in operating room settings in anesthetized patients. Induced abortion is most commonly managed by office vacuum aspiration in awake or sedated patients. Medical evidence does not support routine operating room management of early pregnancy failure. This commentary reviews historical origins of these different care standards, explores political factors responsible for their perpetuation, and uses experience at University of Michigan to dramatize the ways in which history, politics, and biomedicine intersect to produce patient care. The University of Michigan initiated office uterine evacuations for early pregnancy failure treatment. Patients previously went to the operating room. These changes required faculty, staff, and resident education. Our efforts blurred the lines between spontaneous and induced abortion management, improved patient care and better utilized hospital resources.

Approaches to the History of Patients: From the Ancient World to Early Modern Europe.

PubMed

Stolberg, Michael

2016-01-01

This chapter looks from an early modernist's perspective at some of the major questions and methodological issues that writing the history of patients in the ancient world shares with similar work on Patientengeschichte in medieval and early modern Europe. It addresses, in particular, the problem of finding adequate sources that give access to the patients' experience of illness and medicine and highlights the potential as well as the limitations of using physicians' case histories for that purpose. It discusses the doctor-patient relationship as it emerges from these sources, and the impact of the patient's point of view on learned medical theory and practice. In conclusion, it pleads for a cautious and nuanced approach to the controversial issue of retrospective diagnosis, recommending that historians consistently ask in which contexts and in what way the application of modern diagnostic labels to pre-modern accounts of illness can truly contribute to a better historical understanding rather than distort it.

Telomere biology in aging and cancer: early history and perspectives.

PubMed

Hayashi, Makoto T

2018-01-20

The ends of eukaryotic linear chromosomes are protected from undesired enzymatic activities by a nucleoprotein complex called the telomere. Expanding evidence indicates that telomeres have central functions in human aging and tumorigenesis. While it is undoubtedly important to follow current advances in telomere biology, it is also fruitful to be well informed in seminal historical studies for a comprehensive understanding of telomere biology, and for the anticipation of future directions. With this in mind, I here summarize the early history of telomere biology and current advances in the field, mostly focusing on mammalian studies relevant to aging and cancer.

Associations of personal and family preeclampsia history with the risk of early-, intermediate- and late-onset preeclampsia.

PubMed

Boyd, Heather A; Tahir, Hassaan; Wohlfahrt, Jan; Melbye, Mads

2013-12-01

Preeclampsia encompasses multiple conditions of varying severity. We examined the recurrence and familial aggregation of preeclampsia by timing of onset, which is a marker for severity. We ascertained personal and family histories of preeclampsia for women who delivered live singletons in Denmark in 1978-2008 (almost 1.4 million pregnancies). Using log-linear binomial regression, we estimated risk ratios for the associations between personal and family histories of preeclampsia and the risk of early-onset (before 34 weeks of gestation, which is typically the most severe), intermediate-onset (at 34-36 weeks of gestation), and late-onset (after 36 weeks of gestation) preeclampsia. Previous early-, intermediate-, or late-onset preeclampsia increased the risk of recurrent preeclampsia with the same timing of onset 25.2 times (95% confidence interval (CI): 21.8, 29.1), 19.7 times (95% CI: 17.0, 22.8), and 10.3 times (95% CI: 9.85, 10.9), respectively, compared with having no such history. Preeclampsia in a woman's family was associated with a 24%-163% increase in preeclampsia risk, with the strongest associations for early- and intermediate-onset preeclampsia in female relatives. Preeclampsia in the man's family did not affect a woman's risk of early-onset preeclampsia and was only weakly associated with her risks of intermediate- and late-onset preeclampsia. Early-onset preeclampsia appears to have the largest genetic component, whereas environmental factors likely contribute most to late-onset preeclampsia. The role of paternal genes in the etiology of preeclampsia appears to be limited.

Sequence stratigraphy on an early wet Mars

NASA Astrophysics Data System (ADS)

Barker, Donald C.; Bhattacharya, Janok P.

2018-02-01

The evolution of Mars as a water-bearing body is of considerable interest for the understanding of its early history and evolution. The principles of terrestrial sequence stratigraphy provide a useful conceptual framework to hypothesize about the stratigraphic history of the planets northern plains. We present a model based on the hypothesized presence of an early ocean and the accumulation of lowland sediments eroded from highland terrain during the time of the valley networks and later outflow channels. Ancient, global environmental changes, induced by a progressively cooling climate would have led to a protracted loss of surface and near surface water from low-latitudes and eventual cold-trapping at higher latitudes - resulting in a unique and prolonged, perpetual forced regression within basins and lowland depositional environments. The Messinian Salinity Crisis (MSC) serves as a potential terrestrial analogue of the depositional and environmental consequences relating to the progressive removal of large standing bodies of water. We suggest that the evolution of similar conditions on Mars would have led to the emplacement of diagnostic sequences of deposits and regional scale unconformities, consistent with intermittent resurfacing of the northern plains and the progressive loss of an early ocean by the end of the Hesperian era.

Late Pliocene Depositional History and Paleoclimate Reconstructions of the Southwest Pacific

NASA Astrophysics Data System (ADS)

Royce, B.; Patterson, M. O.; Pietras, J.

2017-12-01

Drift deposits off the eastern margin of New Zealand are important archives for the paleoclimate and paleoceanographic history of the southwest Pacific. Ocean Drilling Program (ODP) Site 1123 is located on the North Chatham rise drift just North of the westerly wind driven Subtropical Front (STF) and provides a record of near continuous sediment deposition since the Miocene along the southwest Pacific deep western boundary current (DWBC). While the Miocene and Late Pleistocene portion of this record have been well studied, the Late Pliocene record is less well developed. Southern Ocean geological records demonstrate that Late Pliocene cooling is the transient time bracketing the warmer than present Early Pliocene and bipolar glaciation at 2.7 Ma. A newly developed, robust, and astronomically tuned long-term record of benthic δ13C from ODP Site 1123 spanning the Early to Late Pliocene implies a reduction in Southern Ocean ventilation and lowering of preformed values from waters sourced along the Antarctic margin during the Late Pliocene. Thus, Late Pliocene Southern Hemisphere cooling and sea ice expansion may have drastically reduced outgassing and increased the burial of heat into the deep ocean. South Atlantic records off the west coast of Africa demonstrate an increase in the flux of iron to the open ocean during this time potentially enhancing surface ocean productivity and providing an additional cooling mechanism. Currently, atmospheric transport of dust to the Southern Ocean is dominated by persistent mid-latitude circumpolar westerly winds; this is particularly relevant for dust sourced from New Zealand. The Late Pliocene to Early Pleistocene uplift of the North Island axial ranges and South Island southern alps potentially provided a greater amount of not only sediment to the deep ocean, but also wind blow dust to the Pacific sector of the Southern Ocean. We will present a detailed high-resolution sedimentological study on the development of the Chatham

Cation ordering in orthopyroxenes and cooling rates of meteorites: Low temperature cooling rates of Estherville, Bondoc and Shaw

NASA Technical Reports Server (NTRS)

Ganguly, J.; Yang, H.; Ghose, S.

1993-01-01

The cooling rates of meteorites provide important constraints on the size of their parent bodies, and their accretionary and evolutionary histories. However, the cooling rates obtained so far from the commonly used metallographic, radiometric and fission-track methods have been sometimes quite controversial, such as in the case of the mesosiderites and the meteorite Shaw. We have undertaken a systematic study of the cooling rates of meteorites using a different approach, which involves single crystal x-ray determination of Fe(2+)-Mg ordering in orthopyroxenes (OP(x)) in meteorites, subject to bulk compositional constraints, and numerical simulation of the evolution of the ordering state as a function of cooling rate, within the framework of the thermodynamic and kinetic principles governing cation ordering. We report the results obtained for OP(x) crystals from Shaw and two mesosiderites, Estherville and Bondoc.

Tensions in Constructions of Quality in Australian Early Childhood Education and Care Policy History

ERIC Educational Resources Information Center

Logan, Helen

2017-01-01

In pronouncements of early childhood education and care (ECEC) policy the importance of quality appears as a seemingly irrefutable concept. Yet, attention to ECEC policy history reveals tensions between discourses that construct quality in ways that endure whereas other ways are ostensibly forgotten. Drawing on a Foucauldian-influenced…

Non-lethal effects of an invasive species in the marine environment: the importance of early life-history stages.

PubMed

Rius, Marc; Turon, Xavier; Marshall, Dustin J

2009-04-01

Studies examining the effects of invasive species have focussed traditionally on the direct/lethal effects of the invasive on the native community but there is a growing recognition that invasive species may also have non-lethal effects. In terrestrial systems, non-lethal effects of invasive species can disrupt early life-history phases (such as fertilisation, dispersal and subsequent establishment) of native species, but in the marine environment most studies focus on adult rather than early life-history stages. Here, we examine the potential for an introduced sessile marine invertebrate (Styela plicata) to exert both lethal and non-lethal effects on a native species (Microcosmus squamiger) across multiple early life-history stages. We determined whether sperm from the invasive species interfered with the fertilisation of eggs from the native species and found no effect. However, we did find strong effects of the invasive species on the post-fertilisation performance of the native species. The invasive species inhibited the settlement of native larvae and, in the field, the presence of the invasive species was associated with a ten-fold increase in the post-settlement mortality of the native species, as well as an initial reduction of growth in the native. Our results suggest that larvae of the native species avoid settling near the invasive species due to reduced post-settlement survival in its presence. Overall, we found that invasive species can have complex and pervasive effects (both lethal and non-lethal) across the early life-history stages of the native species, which are likely to result in its displacement and to facilitate further invasion.

The fascinating early history of optics! Archaeological optics 2009: our knowledge of the early history of lenses, mirrors, and artificial eyes!

NASA Astrophysics Data System (ADS)

Enoch, Jay M.

2009-08-01

The early history of optics and vision science (older term: physiological optics) is indeed fascinating. The earliest known true lenses have been found in "eyes" of Egyptian statues which contain superb, complex, and well-polished eye-lens units. The oldest ones known are dated circa 2575 BCE = BC, Dynasty IV, Old Kingdom. These eye-lens units induce a fascinating and powerful visual illusion, but they are just too good to have been the first lenses, or even the first lenses of this design! So saying, no earlier dateable lenses have been found in Egypt or elsewhere. Recently, at the Boston Museum of Fine Arts, the writer noted a previously undetected lens in this series (a first in the Western Hemisphere). Oddly, dateable simpler magnifying lenses and burning glasses seem to have appeared later in time (?)! Manufactured mirrors are quite a bit older, dating from circa 6000 BCE in atal Hyk, located in south-central modern-day Turkey. Using these ancient mirrors, the image quality obtained is remarkable! Recently discovered ancient artificial eyes, located, in situ, in exhumed corpses, have been dated circa 3000 BCE (one discovered in Iran) 5000 BCE (one found in Spain). On the 3000 BCE artificial eye, there are drawn light rays (the writer believes these to be the oldest known depiction of light rays!) spreading out from (or passing into) the iris/ pupil border! Added interesting aspects associated with the early development of light-rays are considered. Thus, early optics can be readily traced back to the Neolithic era (the new stone age), and in some cases before that time period. We have deep roots indeed!

Trace elements record complex histories in diogenites

NASA Astrophysics Data System (ADS)

Balta, J. B.; Beck, A. W.; McSween, H. Y.

2012-12-01

Diogenite meteorites are cumulate rocks composed mostly of orthopyroxene and chemically linked to eucrites (basaltic) and howardites (brecciated mixtures of diogenites and eucrites). Together, they represent the largest single family of achondrite meteorites delivered to Earth, and have been spectrally linked to the asteroid 4 Vesta, the largest remaining basaltic protoplanet. However, this spectral link is non-unique as many basaltic asteroids likely formed and were destroyed in the early solar system. Recent work suggested that Vesta may be an unlikely parent body for the diogenites based on correlations between trace elements and short-lived isotope decay products, which would be unlikely to survive on a body as large as Vesta due to its long cooling history [1]. Recent analyses of terrestrial and martian olivines have demonstrated that trace element spatial distributions can preserve evidence of their crystallization history even when major elements have been homogenized [2]. We have mapped minor elements including Cr, Al, and Ti in seemingly homogeneous diogenite orthopyroxenes and found a variety of previously unobserved textures. The pyroxenes in one sample (GRA 98108) are seemingly large grains of variable shapes and sizes, but the trace elements reveal internal grain boundaries between roughly-equal sized original subgrains, with equilibrated metamorphic triple junctions between them and trace element depletions at the boundaries. These trends suggest extraction of trace elements by a magma along those relict grain boundaries during a reheating event. Two other samples show evidence of fracturing and annealing, with trace element mobility within grains. One sample appears to have remained a closed system during annealing (MET 01084), while the other has interacted with a fluid or magma to move elements along annealed cracks (LEW 88679). These relict features establish that the history of diogenite pyroxenes is more complex than their homogeneous major

A review of noble gas geochemistry in relation to early Earth history

NASA Technical Reports Server (NTRS)

Kurz, M. D.

1985-01-01

One of the most fundamental noble gas constraints on early Earth history is derived from isotopic differences in (129)Xe/(130)Xe between various terrestrial materials. The short half life (17 m.y.) of extinct (129I, parent of (129)Xe, means that these differences must have been produced within the first 100 m.y. after terrestrial accretion. The identification of large anomalies in (129)Xe/(130)Xe in mid ocean ridge basalts (MORB), with respect to atmospheric xenon, suggests that the atmosphere and upper mantle have remained separate since that time. This alone is a very strong argument for early catastrophic degassing, which would be consistent with an early fractionation resulting in core formation. However, noble gas isotopic systematics of oceanic basalts show that the mantle cannot necessarily be regarded as a homogeneous system, since there are significant variations in (3)He/(4)He, (40)Ar/(36)Ar, and (129)Xe/(130)Xe. Therefore, the early degassing cannot be considered to have acted on the whole mantle. The specific mechanisms of degassing, in particular the thickness and growth of the early crust, is an important variable in understanding present day noble gas inventories. Another constraint can be obtained from rocks that are thought to be derived from near the lithosphere asthenosphere boundary: ultramafic xenoliths.

Development and Early Usage Patterns of a Consumer-Facing Family Health History Tool

PubMed Central

Hulse, Nathan C.; Ranade-Kharkar, Pallavi; Post, Herman; Wood, Grant M.; Williams, Marc S.; Haug, Peter J.

2011-01-01

Personalized medicine will require detailed clinical patient profiles, and a particular focus on capturing data that is useful in forecasting risk. A detailed family health history is considered a critical component of these profiles, insomuch that it has been coined as ‘the best genetic test available’. Despite this, tools aimed at capturing this information for use in electronic health records have been characterized as inadequate. In this manuscript we detail the creation of a patient-facing family health history tool known as OurFamilyHealth, whose long-term emphasis is to facilitate risk assessment and clinical decision support. We present the rationale for such a tool, describe its development and release as a component of Intermountain Healthcare’s patient portal, and detail early usage statistics surrounding the application. Data derived from the tool since its release are also compared against family history charting patterns in Intermountain’s electronic health records, revealing differences in data availability. PMID:22195113

DESI focal plate mechanical integration and cooling

NASA Astrophysics Data System (ADS)

Lambert, A. R.; Besuner, R. W.; Claybaugh, T. M.; Silber, J. H.

2016-08-01

The Dark Energy Spectroscopic Instrument (DESI) is under construction to measure the expansion history of the Universe using the Baryon Acoustic Oscillation technique[1]. The spectra of 40 million galaxies over 14000 sq. deg will be measured during the life of the experiment. A new prime focus corrector for the KPNO Mayall telescope will deliver light to 5000 fiber optic positioners. The fibers in turn feed ten broad-band spectrographs. This paper describes the mechanical integration of the DESI focal plate and the thermal system design. The DESI focal plate is comprised of ten identical petal assemblies. Each petal contains 500 robotic fiber positioners. Each petal is a complete, self-contained unit, independent from the others, with integrated power supply, controllers, fiber routing, and cooling services. The major advantages of this scheme are: (1) supports installation and removal of complete petal assemblies in-situ, without disturbing the others, (2) component production, assembly stations, and test procedures are repeated and parallelizable, (3) a complete, full-scale prototype can be built and tested at an early date, (4) each production petal can be surveyed and tested as a complete unit, prior to integration, from the fiber tip at the focal surface to the fiber slit at the spectrograph. The ten petal assemblies will be installed in a single integration ring, which is mounted to the DESI corrector. The aluminum integration ring attaches to the steel corrector barrel via a flexured steel adapter, isolating the focal plate from differential thermal expansions. The plate scale will be kept stable by conductive cooling of the petal assembly. The guider and wavefront sensors (one per petal) will be convectively cooled by forced flow of air. Heat will be removed from the system at ten liquid-cooled cold plates, one per petal, operating at ambient temperature. The entire focal plate structure is enclosed in an insulating shroud, which serves as a thermal barrier

The "Starch Wars" and the Early History of DNA Profiling.

PubMed

Aronson, J D

2006-01-01

Just as the movie Star Wars had a prequel, so did the "DNA Wars"-the series of legal, scientific, and personal battles that took place over the admissibility of forensic DNA evidence from 1989 to 1994. Between the late 1970s and the mid-1980s, another forensic identification technique became mired in controversy: electrophoresis-based blood protein analysis. Although the debates over blood analysis were every bit as rancorous and frustrating to almost everybody involved - so much so that they became known as the "Starch Wars" - their importance has not been adequately appreciated in the recent history of forensic science. After reviewing the early history of blood typing, I will describe the development of the Multi-System approach to blood protein analysis that took place in California from 1977 to 1978. I will then elucidate the history of the Starch Wars, and demonstrate the ways that they shaped subsequent disputes over DNA evidence, especially in California. I will show that: (a) many of the forensic scientists, law enforcement officials, and lawyers who became prominent players in the DNA Wars were deeply involved in the court cases involving protein electrophoresis; and (b) many of the issues that became controversial in the disputes over DNA evidence first emerged in the Starch Wars. In the conclusion, I will suggest various ways to improve the quality of forensic science based on my analysis of the Starch Wars. Copyright © 2006 Central Police University.

Relative value of race, family history and prostate specific antigen as indications for early initiation of prostate cancer screening.

PubMed

Vertosick, Emily A; Poon, Bing Ying; Vickers, Andrew J

2014-09-01

Many guidelines suggest earlier screening for prostate cancer in men at high risk, with risk defined in terms of race and family history. Recent evidence suggests that baseline prostate specific antigen is strongly predictive of the long-term risk of aggressive prostate cancer. We compared the usefulness of risk stratifying early screening by race, family history and prostate specific antigen at age 45 years. Using estimates from the literature we calculated the proportion of men targeted for early screening using family history, black race or prostate specific antigen as the criterion for high risk. We calculated the proportion of prostate cancer deaths that would occur in those men by age 75 years. Screening based on family history involved 10% of men, accounting for 14% of prostate cancer deaths. Using black race as a risk criterion involved 13% of men, accounting for 28% of deaths. In contrast, 44% of prostate cancer deaths occurred in the 10% of men with the highest prostate specific antigen at age 45 years. In no sensitivity analysis for race and family history did the ratio of risk group size to number of prostate cancer deaths in that risk group approach that of prostate specific antigen. Basing decisions for early screening on prostate specific antigen at age 45 years provided the best ratio between men screened and potential cancer deaths avoided. Given the lack of evidence that race or family history affects the relationship between prostate specific antigen and risk, prostate specific antigen based risk stratification would likely include any black men or men with a family history who are destined to experience aggressive disease. Differential screening based on risk should be informed by baseline prostate specific antigen. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Highly ionized atoms in cooling gas

NASA Technical Reports Server (NTRS)

Edgar, R. J.; Chevalier, R. A.

1986-01-01

The ionization of low density gas cooling from a high temperature was calculated. The evolution during the cooling is assumed to be isochoric, isobaric, or a combination of these cases. The calculations are used to predict the column densities and ultraviolet line luminosities of highly ionized atoms in cooling gas. In a model for cooling of a hot galactic corona, it is shown that the observed value of N(N V) can be produced in the cooling gas, while the predicted value of N(Si IV) falls short of the observed value by a factor of about 5. The same model predicts fluxes of ultraviolet emission lines that are a factor of 10 lower than the claimed detections of Feldman, Brune, and Henry. Predictions are made for ultraviolet lines in cooling flows in early-type galaxies and clusters of galaxies. It is shown that the column densities of interest vary over a fairly narrow range, while the emission line luminosities are simply proportional to the mass inflow rate.

300 million years of basin evolution - the thermotectonic history of the Ukrainian Donbas Foldbelt

NASA Astrophysics Data System (ADS)

Spiegel, C.; Danisik, M.; Sachsenhofer, R.; Frisch, W.; Privalov, V.

2009-04-01

The Ukrainian-Russian Pripyat-Dniepr-Donets Basin is a large intracratonic rift structure formed during the Late Devonian. It is situated at the southern margin of the Precambrian East European Craton, adjacent to the Hercynian Tethyan belt in the Black Sea area and the Alpine Caucasus orogen. With a sediment thickness of more than 20 km, it is one of the deepest sedimentary basins on earth. The eastern part of the Pripyat-Dniepr-Donets Basin - called Donbas foldbelt - is strongly folded and inverted. Proposed models of basin evolution are often controversial and numerous issues are still a matter of speculation, particularly the erosion history and the timing of basin inversion. Basin inversion may have taken place during the Permian related to the Uralian orogeny, or in response to Alpine tectonics during the Late Cretaceous to Early Tertiary. We investigated the low-temperature thermal history of the Donbas Foldbelt and the adjacent Ukrainian shield by a combination of zircon fission track, apatite fission track and apatite (U-Th)/He thermochronology. Although apatite fission track ages of all sedimentary samples were reset shortly after deposition during the Carboniferous, we took advantage of the fact that samples contained kinetically variable apatites, which are sensitive to different temperatures. By using statistic-based component analysis incorporating physical properties of individual grains we identified several distinct age population, ranging from late Permian (~265 Ma) to the Late Cretaceous (70 Ma). We could thus constrain the thermal history of the Donbas Foldbelt and the adjacent basement during a ~300 Myr long time period. The Precambrian crystalline basement of the Ukrainian shield was affected by a Permo-Triassic thermal event associated with magmatic activity, which also strongly heated the sediments of the Donbas Foldbelt. The basement rocks cooled to near-surface conditions during the Early to Middle Triassic and since then was thermally

Effect of Impacts on the Cooling Rates of Differentiated Planetesimals

NASA Astrophysics Data System (ADS)

Lyons, R. J.; Bowling, T. J.; Ciesla, F. J.; Davison, T. M.; Collins, G. S.

2018-05-01

I have modeled planetismal impacts in the early solar system, following their formation, differentiation, and cooling. I found that small collisions can expose the core, resulting in more than an order of magnitude increase in the cooling rates.

Thermal and exhumation history of the central Tianshan (NW China): Constraints by U-Pb geochronology and Ar-Ar and (U-Th)/He thermochronology

NASA Astrophysics Data System (ADS)

Yin, J.; Chen, W.; Hodges, K. V.; Xiao, W.; Van Soest, M. C.; Cai, K.; Zhang, B.; Mercer, C. M.; Yuan, C.

2015-12-01

Geochronology and thermochronology using multiple mineral-isotopic chronometers reveals the thermo-tectonic history of the central Tianshan (NW China) from emplacement to exhumation. Granites from the central Tianshan, which are associated with the southward subduction of the northern Tianshan Ocean, have been dated at 362-354 Ma using the LA-ICP-MS Zircon U-Pb method. A younger diorite sample (282 ± 1 Ma, Zircon U-Pb method by LA-ICP-MS) from northern Tianshan formed during the final closure of the Northern Tianshan Ocean when the Junggar Block collided with the Yili-Central Tianshan Block. 40Ar/39Ar step-wise heating plateau dates (biotite Ar/Ar: 312-293 Ma; Plagioclase Ar/Ar: 270-229 Ma) from the Central Tianshan show rapid post-magmatic cooling during the Late Carboniferous-Early Permian followed by a more modest rate of cooling from the middle Permian to the middle Jurassic. The northern Tianshan diorite (biotite Ar/Ar: 240 ± 1 Ma) also reveals a middle Jurassic cooling. Apatite (U-Th )/He dates from the central Tianshan samples range from ca. 130 Ma to ca. 116 Ma. The Apatite (U-Th )/He date for the northern Tianshan sample is ca. 27 Ma. Previous studies also reported Apatite (U-Th)/He ages of ca. 44 Ma-11 Ma in the Baluntai area of the southern Central Tianshan[1]. Two episodes of cooling are distinguished by thermal history modelling: (1) Mesozoic cooling occurred as the result of the exhumation and tectonic reactivation of the central Tianshan; and (2) The Tianshan orogenic belt has been rapidly exhumed since the Middle Cenozoic. References [1] Lü, H.H., Chang, Y., Wang, W., Zhou, Z.Y., 2013. Rapid exhumation of the Tianshan Mountains since the early Miocene: Evidence from combined apatite fission track and (U-Th)/He thermochronology. Science China: Earth Sciences, 43(12): 1964-1974 (in Chinese).

Francis Bacon's natural history and the Senecan natural histories of early modern Europe.

PubMed

Jalobeanu, Dana

2012-01-01

At various stages in his career, Francis Bacon claimed to have reformed and changed traditional natural history in such a way that his new "natural and experimental history" was unlike any of its ancient or humanist predecessors. Surprisingly, such claims have gone largely unquestioned in Baconian scholarship. Contextual readings of Bacon's natural history have compared it, so far, only with Plinian or humanist natural history. This paper investigates a different form of natural history, very popular among Bacon's contemporaries, but yet unexplored by contemporary students of Bacon's works. I have provisionally called this form of natural history'Senecan' natural history, partly because it took shape in the Neo-Stoic revival of the sixteenth-century, partly because it originates in a particular cosmographical reading of Seneca's Naturales quaestiones. I discuss in this paper two examples of Senecan natural history: the encyclopedic and cosmographical projects of Pierre de la Primaudaye (1546-1619) and Samuel Purchas (1577-1626). I highlight a number of similarities between these two projects and Francis Bacon's natural history, and argue that Senecan natural history forms an important aspect in the historical and philosophical background that needs to be taken into consideration if we want to understand the extent to which Bacon's project to reform natural history can be said to be new.

Cumulative Effects of Nutrient Enrichment and Elevated Temperature Compromise the Early Life History Stages of the Coral Acropora tenuis

PubMed Central

Noonan, Sam H. C.; Willis, Bette L.; Fabricius, Katharina E.; Negri, Andrew P.

2016-01-01

Inshore coral reefs are experiencing the combined pressures of excess nutrient availability associated with coastal activities and warming seawater temperatures. Both pressures are known to have detrimental effects on the early life history stages of hard corals, but studies of their combined effects on early demographic stages are lacking. We conducted a series of experiments to test the combined effects of nutrient enrichment (three levels) and elevated seawater temperature (up to five levels) on early life history stages of the inshore coral Acropora tenuis, a common species in the Indo-Pacific and Red Sea. Gamete fertilization, larval survivorship and larval settlement were all significantly reduced as temperature increased, but only fertilization was further affected by simultaneous nutrient enrichment. Combined high temperatures and nutrient enrichment affected fertilization in an additive manner, whereas embryo abnormalities increased synergistically. Higher than normal temperatures (32°C) increased coral juvenile growth rates 1.6-fold, but mortality also increased by 50%. The co-occurrence of nutrient enrichment with high temperatures reduced juvenile mortality to 36%, ameliorating temperature stress (antagonistic interaction). Overall, the types of effect (additive vs synergistic or antagonistic) and their magnitude varied among life stages. Gamete and embryo stages were more affected by temperature stress and, in some cases, also by nutrient enrichment than juveniles. The data suggest that coastal runoff events might exacerbate the impacts of warming temperatures on fertilization if these events co-occur during corals spawning. The cumulative impacts of simultaneous exposure to nutrient enrichment and elevated temperatures over all early life history stages increases the likelihood for failure of larval supply and recruitment for this coral species. Our results suggest that improving the water quality of river discharges into coastal areas might help to

Building an Evidence-Based Mental Health Program for Children with History of Early Adversity

ERIC Educational Resources Information Center

Kroupina, Maria; Vermeulen, Marlous; Moberg, Stephanie

2015-01-01

Adoption is a major intervention in a child's life, however internationally adopted (IA) children remain at risk for long-term neurodevelopmental and mental health issues due to the fact that most of them have a history of early adversity prior to their adoption. In the last 20 years, extensive research with this population has increased the…

Cooling and exhumation of continents at billion-year time scales

NASA Astrophysics Data System (ADS)

Blackburn, T.; Bowring, S. A.; Perron, T.; Mahan, K. H.; Dudas, F. O.

2011-12-01

The oldest rocks on Earth are preserved within the continental lithosphere, where assembled fragments of ancient orogenic belts have survived erosion and destruction by plate tectonic and surface processes for billions of years. Though the rate of orogenic exhumation and erosion has been measured for segments of an orogenic history, it remains unclear how these exhumation rates have changed over the lifetime of any terrane. Because the exhumation of the lithospheric surface has a direct effect on the rate of heat loss within the lithosphere, a continuous record of lithosphere exhumation can be reconstructed through the use of thermochronology. Thermochronologic studies have typically employed systems sensitive to cooling at temperatures <300 °C, such as the (U-Th)/He and 40Ar/39Ar systems. This largely restricts their application to measuring cooling in rocks from the outer 10 km of the Earth's crust, resulting in a thermal history that is controlled by either upper crustal flexure and faulting and/or isotherm inflections related to surface topography. Combining these biases with the uplift, erosion and recycling of these shallow rocks results in a poor preservation potential of any long-term record. Here, an ancient and long-term record of lithosphere exhumation is constructed using U-Pb thermochronology, a geochronologic system sensitive to cooling at temperatures found at 20-50 km depth (400-650 °C). Lower crustal xenoliths provide material that resided at these depths for billions of years or more, recording a thermal history that is buried deep enough to remain insensitive to upper crustal deformation and instead is dominated by the vertical motions of the continents. We show how this temperature-sensitive system can produce a long-term integrated measure of continental exhumation and erosion. Preserved beneath Phanerozoic sedimentary rocks within Montana, USA, the Great Falls Tectonic Zone formed when two Archean cratons, the Wyoming Province and Medicine

Early life history pelagic exposure profiles of selected commercially important fish species in the Gulf of Alaska

NASA Astrophysics Data System (ADS)

Doyle, Miriam J.; Mier, Kathryn L.

2016-10-01

A synthesis of nearly four decades of ichthyoplankton survey data from the Gulf of Alaska was undertaken to provide the most comprehensive information available on the early life history ecology of five focal species: Pacific Cod (Gadus macrocephalus), Walleye Pollock (Gadus chalcogrammus), Pacific Ocean Perch (Sebastes alutus), Sablefish (Anoplopoma fimbria), and Arrowtooth Flounder (Atheresthes stomias). This analysis of historical data, along with information from published studies, is presented here in the form of ecological reviews of the species during their planktonic phase. The reviews include descriptions of temporal and spatial patterns of exposure to the environment, and interpretation regarding associated sensitivities to environmental forcing. On a temporal scale, patterns in abundance of eggs and larvae are synthesized that characterize seasonal exposure to the pelagic environment, and interannual variation that is presumed to incorporate responses to long-term environmental forcing. Spatial patterns are synthesized to identify horizontal and vertical extent of egg and larval distributions, delineate areas of primary larval habitat, and illuminate egg and larval drift pathways. The observed patterns are discussed with respect to characterizing species early life history strategies, identifying long-term adaptations to the Gulf of Alaska environment, and associated resilience and vulnerability factors that may modulate early life responses to environmental forcing in this region. For each species, gaps in knowledge are identified and are concerned primarily with the period of transition between the larval and juvenile stage, and feeding habits and ecology across seasons, habitats and sub-intervals of early ontogeny. These early life history reviews advance our ecological understanding of the pelagic phase, and fine-tune our focus for the investigation of potential response mechanisms to environmental forcing at appropriate, species-specific temporal

Interview with Paul W. Kruse on the Early History of HgCdTe, Conducted on October 22, 1980

NASA Astrophysics Data System (ADS)

Reine, Marion B.

2015-09-01

This paper presents an interview with Dr Paul W. Kruse (1927-2012) on the early history of the semiconductor alloy mercury cadmium telluride (HgCdTe or Hg1- x Cd x Te) at the Honeywell Corporate Research Center near Minneapolis, Minnesota. Conducted on October 22, 1980, the interview covers two main areas. One area is the story of how the HgCdTe research effort came about at the Honeywell Research Center in the early 1960s, what technical choices were made and when, and what technical challenges were overcome and how. The other area is the organization, culture, environment and personnel at the Honeywell Research Center that made the early HgCdTe research programs so successful. HgCdTe has emerged as the highest-performance, most widely applicable infrared detector material. HgCdTe continues to satisfy a broad variety of advanced military and space applications. It is illustrative to look back on the early history of this remarkable semiconductor alloy to help to understand why its technological development as an infrared detector has been so successful.

Origin of two maxima in specific heat in enthalpy relaxation under thermal history composed of cooling, annealing, and heating.

PubMed

Sakatsuji, Waki; Konishi, Takashi; Miyamoto, Yoshihisa

2016-12-01

The origin of two maxima in specific heat observed at the higher and the lower temperatures in the glass-transition region in the heating process has been studied for polymethyl methacrylate and polyvinyl chloride using differential scanning calorimetry, and the calculation was done using the phenomenological model equation under a thermal history of the typical annealing experiment composed of cooling, annealing, and heating. The higher maximum is observed above the glass-transition temperature, and it remains almost unchanged independent of annealing time t_{a}, while the lower one is observed above an annealing temperature T_{a} and shifts toward the higher one, increasing its magnitude with t_{a}. The analysis by the phenomenological model equation proposed in order to interpret the memory effect in the glassy state clarifies that under a typical annealing history, two maxima in specific heat essentially appear. The shift of the lower maximum toward higher temperatures from above T_{a} is caused by an increase in the amount of relaxation during annealing with t_{a}. The annealing temperature and the amount of relaxation during annealing play a major role in the determination of the number of maxima in the specific heat.

Genomic evidence for rod monochromacy in sloths and armadillos suggests early subterranean history for Xenarthra

PubMed Central

Emerling, Christopher A.; Springer, Mark S.

2015-01-01

Rod monochromacy is a rare condition in vertebrates characterized by the absence of cone photoreceptor cells. The resulting phenotype is colourblindness and low acuity vision in dim-light and blindness in bright-light conditions. Early reports of xenarthrans (armadillos, sloths and anteaters) suggest that they are rod monochromats, but this has not been tested with genomic data. We searched the genomes of Dasypus novemcinctus (nine-banded armadillo), Choloepus hoffmanni (Hoffmann's two-toed sloth) and Mylodon darwinii (extinct ground sloth) for retinal photoreceptor genes and examined them for inactivating mutations. We performed PCR and Sanger sequencing on cone phototransduction genes of 10 additional xenarthrans to test for shared inactivating mutations and estimated the timing of inactivation for photoreceptor pseudogenes. We concluded that a stem xenarthran became an long-wavelength sensitive-cone monochromat following a missense mutation at a critical residue in SWS1, and a stem cingulate (armadillos, glyptodonts and pampatheres) and stem pilosan (sloths and anteaters) independently acquired rod monochromacy early in their evolutionary history following the inactivation of LWS and PDE6C, respectively. We hypothesize that rod monochromacy in armadillos and pilosans evolved as an adaptation to a subterranean habitat in the early history of Xenarthra. The presence of rod monochromacy has major implications for understanding xenarthran behavioural ecology and evolution. PMID:25540280

Fracture patterns at lava-ice contacts on Kokostick Butte, OR, and Mazama Ridge, Mount Rainier, WA: Implications for flow emplacement and cooling histories

NASA Astrophysics Data System (ADS)

Lodge, Robert W. D.; Lescinsky, David T.

2009-09-01

Cooling lava commonly develop polygonal joints that form equant hexagonal columns. Such fractures are formed by thermal contraction resulting in an isotropic tensional stress regime. However, certain linear cooling fracture patterns observed at some lava-ice contacts do not appear to fit the model for formation of cooling fractures and columns because of their preferred orientations. These fracture types include sheet-like (ladder-like rectangular fracture pattern), intermediate (pseudo-aligned individual column-bounding fractures), and pseudopillow (straight to arcuate fractures with perpendicular secondary fractures caused by water infiltration) fractures that form the edges of multiple columns along a single linear fracture. Despite the relatively common occurrence of these types of fractures at lava-ice contacts, their significance and mode of formation have not been fully explored. This study investigates the stress regimes responsible for producing these unique fractures and their significance for interpreting cooling histories at lava-ice contacts. Data was collected at Kokostick Butte dacite flow at South Sister, OR, and Mazama Ridge andesite flow at Mount Rainier, WA. Both of these lava flows have been interpreted as being emplaced into contact with ice and linear fracture types have been observed on their ice-contacted margins. Two different mechanisms are proposed for the formation of linear fracture networks. One possible mechanism for the formation of linear fracture patterns is marginal bulging. Melting of confining ice walls will create voids into which flowing lava can deform resulting in margin-parallel tension causing margin-perpendicular fractures. If viewed from the ice-wall, these fractures would be steeply dipping, linear fractures. Another possible mechanism for the formation of linear fracture types is gravitational settling. Pure shear during compression and settling can result in a tensional environment with similar consequences as

Molecular processes in astrophysics: Calculations of hydrogen + hydrogen gas excitation, de-excitation, and cooling

NASA Astrophysics Data System (ADS)

Kelley, Matthew Thomas

The implications of H+H2 cooling in astrophysics is important to several applications. One of the most significant and pure applications is its role in cooling in the early universe. Other applications would include molecular dynamics in nebulae and their collapse into stars and astrophysical shocks. Shortly after the big bang, the universe was a hot primordial gas of photons, electrons, and nuclei among other ingredients. By far the most dominant nuclei in the early universe was hydrogen. In fact, in the early universe the matter density was 90 percent hydrogen and only 10 percent helium with small amounts of lithium and deuterium. In order for structure to form in the universe, this primordial gas must form atoms and cool. One of the significant cooling mechanisms is the collision of neutral atomic hydrogen with a neutral diatomic hydrogen molecule. This work performs calculations to determine collisional cooling rates of hydrogen using two potential surfaces.

Cooled radiofrequency ablation for bilateral greater occipital neuralgia.

PubMed

Vu, Tiffany; Chhatre, Akhil

2014-01-01

This report describes a case of bilateral greater occipital neuralgia treated with cooled radiofrequency ablation. The case is considered in relation to a review of greater occipital neuralgia, continuous thermal and pulsed radiofrequency ablation, and current medical literature on cooled radiofrequency ablation. In this case, a 35-year-old female with a 2.5-year history of chronic suboccipital bilateral headaches, described as constant, burning, and pulsating pain that started at the suboccipital region and radiated into her vertex. She was diagnosed with bilateral greater occipital neuralgia. She underwent cooled radiofrequency ablation of bilateral greater occipital nerves with minimal side effects and 75% pain reduction. Cooled radiofrequency ablation of the greater occipital nerve in challenging cases is an alternative to pulsed and continuous RFA to alleviate pain with less side effects and potential for long-term efficacy.

Cooled Radiofrequency Ablation for Bilateral Greater Occipital Neuralgia

PubMed Central

Chhatre, Akhil

2014-01-01

This report describes a case of bilateral greater occipital neuralgia treated with cooled radiofrequency ablation. The case is considered in relation to a review of greater occipital neuralgia, continuous thermal and pulsed radiofrequency ablation, and current medical literature on cooled radiofrequency ablation. In this case, a 35-year-old female with a 2.5-year history of chronic suboccipital bilateral headaches, described as constant, burning, and pulsating pain that started at the suboccipital region and radiated into her vertex. She was diagnosed with bilateral greater occipital neuralgia. She underwent cooled radiofrequency ablation of bilateral greater occipital nerves with minimal side effects and 75% pain reduction. Cooled radiofrequency ablation of the greater occipital nerve in challenging cases is an alternative to pulsed and continuous RFA to alleviate pain with less side effects and potential for long-term efficacy. PMID:24716017

An early history of the Gestalt factors of organisation.

PubMed

Vezzani, Stefano; Marino, Barbara F M; Giora, Enrico

2012-01-01

Wertheimer's (1923, Psychologische Forschung 4 301 - 350) idea that the perceptual world is articulated according to factors of organisation is widely acknowledged as one of the most original contributions of Gestalt psychology and stands as a milestone in the history of vision research. An inquiry focused on the forerunners of some of Wertheimer's factors of perceptual organisation is documented here. In fact, in 1900 Schumann described grouping by proximity and by vertical symmetry, and in 1903 G E Müller identified the factors of sameness/similarity and contour. Other authors contributed to the early description of these factors, such as Rubin, who in 1922 originally illustrated grouping by similarity. Even though Wertheimer himself granted these authors due recognition, later psychologists have paid little attention to their contributions. Some possible reasons for this negligence are briefly discussed.

Transient three-dimensional startup side load analysis of a regeneratively cooled nozzle

NASA Astrophysics Data System (ADS)

Wang, Ten-See

2009-07-01

The objective of this effort is to develop a computational methodology to capture the side load physics and to anchor the computed aerodynamic side loads with the available data by simulating the startup transient of a regeneratively cooled, high-aspect-ratio nozzle, hot-fired at sea level. The computational methodology is based on an unstructured-grid, pressure-based, reacting flow computational fluid dynamics and heat transfer formulation, and a transient inlet history based on an engine system simulation. Emphases were put on the effects of regenerative cooling on shock formation inside the nozzle, and ramp rate on side load reduction. The results show that three types of asymmetric shock physics incur strong side loads: the generation of combustion wave, shock transitions, and shock pulsations across the nozzle lip, albeit the combustion wave can be avoided with sparklers during hot-firing. Results from both regenerative cooled and adiabatic wall boundary conditions capture the early shock transitions with corresponding side loads matching the measured secondary side load. It is theorized that the first transition from free-shock separation to restricted-shock separation is caused by the Coanda effect. After which the regeneratively cooled wall enhances the Coanda effect such that the supersonic jet stays attached, while the hot adiabatic wall fights off the Coanda effect, and the supersonic jet becomes detached most of the time. As a result, the computed peak side load and dominant frequency due to shock pulsation across the nozzle lip associated with the regeneratively cooled wall boundary condition match those of the test, while those associated with the adiabatic wall boundary condition are much too low. Moreover, shorter ramp time results show that higher ramp rate has the potential in reducing the nozzle side loads.

The Role of Residential Early Parenting Services in Increasing Parenting Confidence in Mothers with A History of Infertility.

PubMed

Khajehei, Marjan; Finch, Lynette

2016-01-01

Mothers with a history of infertility may experience parenting difficulties and challenges. This study was conducted to investigate the role of residential early parenting services in increasing parenting confidence in mothers with a history of infertility. This was a retrospective chart review study using the quantitative data from the clients attending the Karitane Residential Units and Parenting Services (known as Karitane RUs) during 2013. Parenting confidence (using Karitane Parenting Confidence Scale-KPCS), depression, demographics, reproductive and medical history, as well as child's information were assessed from a sample of 27 mothers who had a history of infertility and who attended the Karitane RUs for support and assistance. The data were analyzed using SPSS version 19. More than half of the women (59.3%) reported a relatively low level of parenting confidence on the day of admission. The rate of low parenting confidence, however, dropped to 22.2% after receiving 4-5 days support and training in the Karitane RUs. The mean score of the KPCS increased from 36.9 ± 5.6 before the intervention to 41.1 ± 3.4 after the intervention, indicating an improvement in the parenting confidence of the mothers after attending the Karitane RUs (P<0.0001). No statistically significant association was found between maternal low parenting confidence with parental demographics (including age, country of birth, and employment status), a history of help-seeking, symptoms of depression, as well as child's information [including gender, age, siblings, diagnosis of gastroesophageal reflux disease (GORD) and use of medication]. Having a child after a period of infertility can be a stressful experience for some mothers. This can result in low parenting confidence and affect parent-child attachment. Our findings emphasized on the role of the residential early parenting services in promoting the level of parenting confidence and highlighted the need for early recognition and

The Role of Residential Early Parenting Services in Increasing Parenting Confidence in Mothers with A History of Infertility

PubMed Central

Khajehei, Marjan; Finch, Lynette

2016-01-01

Background Mothers with a history of infertility may experience parenting difficulties and challenges. This study was conducted to investigate the role of residential early parenting services in increasing parenting confidence in mothers with a history of infertility. Materials and Methods This was a retrospective chart review study using the quantitative data from the clients attending the Karitane Residential Units and Parenting Services (known as Karitane RUs) during 2013. Parenting confidence (using Karitane Parenting Confidence Scale-KPCS), depression, demographics, reproductive and medical history, as well as child’s information were assessed from a sample of 27 mothers who had a history of infertility and who attended the Karitane RUs for support and assistance. The data were analyzed using SPSS version 19. Results More than half of the women (59.3%) reported a relatively low level of parenting confidence on the day of admission. The rate of low parenting confidence, however, dropped to 22.2% after receiving 4-5 days support and training in the Karitane RUs. The mean score of the KPCS increased from 36.9 ± 5.6 before the intervention to 41.1 ± 3.4 after the intervention, indicating an improvement in the parenting confidence of the mothers after attending the Karitane RUs (P<0.0001). No statistically significant association was found between maternal low parenting confidence with parental demographics (including age, country of birth, and employment status), a history of help-seeking, symptoms of depression, as well as child’s information [including gender, age, siblings, diagnosis of gastroesophageal reflux disease (GORD) and use of medication]. Conclusion Having a child after a period of infertility can be a stressful experience for some mothers. This can result in low parenting confidence and affect parent-child attachment. Our findings emphasized on the role of the residential early parenting services in promoting the level of parenting confidence

Cooling rate dependence of the glass transition at free surfaces

NASA Astrophysics Data System (ADS)

Streit-Nierobisch, S.; Gutt, C.; Paulus, M.; Tolan, M.

2008-01-01

In situ x-ray reflectivity measurements are used to determine the cooling rate dependent freezing of capillary waves on the oligomer poly(propylene glycol). Only above the glass transition temperature TG can the surface roughness σ be described by the capillary wave model for simple liquids, whereas the surface fluctuations are frozen-in at temperatures below TG . As the state of a glass forming liquid strongly depends on its thermal history, this effect occurs for fast cooling rates already at a higher temperature than for slow cooling. For the fastest cooling rates a very large shift of TG up to 240K compared to the bulk value of 196K was observed.

Hydration and Cooling Practices Among Farmworkers in Oregon and Washington.

PubMed

Bethel, Jeffrey W; Spector, June T; Krenz, Jennifer

2017-01-01

Although recommendations for preventing occupational heat-related illness among farmworkers include hydration and cooling practices, the extent to which these recommendations are universally practiced is unknown. The objective of this analysis was to compare hydration and cooling practices between farmworkers in Oregon and Washington. A survey was administered to a purposive sample of Oregon and Washington farmworkers. Data collected included demographics, work history and current work practices, hydration practices, access and use of cooling measures, and headwear and clothing worn. Oregon farmworkers were more likely than those in Washington to consume beverages containing sugar and/or caffeine. Workers in Oregon more frequently reported using various cooling measures compared with workers in Washington. Availability of cooling measures also varied between the two states. These results highlight the large variability between workers in two states regarding access to and use of methods to stay cool while working in the heat.

Cool in the Kitchen: Radiation, Conduction, and the Newton "Hot Block" Experiment.

ERIC Educational Resources Information Center

Silverman, Mark P.; Silverman, Christopher R.

2000-01-01

Discusses the history of the development of Newton's Law of Cooling. Describes an experiment conducted in the kitchen that is designed to test the rate of cooling of a hot block of iron. Finds that Newton's law does not represent very well the mechanism of heat loss. (Contains over 10 references.) (WRM)

Biospheric Cooling and the Emergence of Intelligence

NASA Astrophysics Data System (ADS)

Schwartzman, David; Middendorf, George

The long-term cooling history of the Earth's biosphere implies a temperature constraint on the timing of major events in biologic evolution, e.g., emergence of cyanobacteria, eucaryotes and Metazoa apparently occurred at times when temperatures were near their upper growth limits. Could biospheric cooling also have been a necessary condition for the emergence of veterbrates and their encephalization? The upper temperature limit for vertebrate growth is about 10 degrees below the limit for Metazoa (50 degrees C). Heterothermy followed by full homeothermy was likely a necessary condition for greater encephalization because of the energy requirement of larger brains. The temperature differential between an animal and a cooler environment, all other factors equal, will increase the efficiency of heat loss from the brain, but too large a differential will shift metabolic energy away from the brain to the procurement of food. Encephalization has also entailed the evolution of internal cooling mechanisms to avoid overheating the brain. The two periods of pronounced Phanerozoic cooling, the PermoCarboniferous and late Cenozoic, corresponded to the emergence of mammal-like reptiles and hominids respectively, with a variety of explanations offered for the apparent link. The origin of highly encephalized whales, dolphins and porpoises occurred with the drop in ocean temperatures 25-30 mya. Of course, other possible paths to encephalization are conceivable, with radically different solutions to the problem of heat dissipation. But the intrinsic requirements for information processing capacity necessary for intelligence suggest our terrestrial pattern may resemble those of alien biospheres given similar histories.

New insight into the thermal-tectonic history of the southern Antarctic Peninsula: (Uranium-Thorium-Samarium)/Helium and fission-track thermochronologic results from northwest Palmer Land and Alexander Island

NASA Astrophysics Data System (ADS)

Savrda, Amanda Marie

2011-12-01

This study examines the thermal history of the southern Antarctic Peninsula through the application of thermochronometry, and presents the first high-resolution thermochronologic dataset for arc rocks of northwest Palmer Land. I present 19 new thermochronologic ages obtained via (U-Th-Sm)/He and fission-track analyses of apatite and zircon from arc granitoids of northwest Palmer Land and fore-arc rocks of the LeMay and Fossil Bluff Groups of Alexander Island. These data were modeled via Monte Carlo simulations to generate time-temperature pathways. Thermal models generated for arc granitoids of northwest Palmer Land reveal a Late Cretaceous-Early Cenozoic episode of accelerated cooling from ca. 78--55 Ma not previously recognized in the southern Antarctic Peninsula. Here, faster cooling at an average rate of ˜15°C/Myr is bracketed by slower cooling at rates <3°C/Myr. Modeled thermal histories of metamorphosed fore-arc sedimentary rocks of Alexander Island reveal rapid cooling throughout the Eocene at an average rate of ˜13°C/Myr, preceded and followed by slower rates of cooling on the order of <3°C/Myr. The spatial and temporal distribution of the observed cooling trends may reflect localized variations in the thermal regime due to regional changes in plate kinematics, subduction dynamics, and related magmatism, but the cooling rates are also within range of those typical of exhumational processes such as normal faulting, ductile thinning, and erosion.

On the early history of the Finnish Meteorological Institute

NASA Astrophysics Data System (ADS)

Nevanlinna, H.

2014-03-01

This article is a review of the foundation (in 1838) and later developments of the Helsinki (Finland) magnetic and meteorological observatory, today the Finnish Meteorological Institute (FMI). The main focus of the study is in the early history of the FMI up to the beginning of the 20th century. The first director of the observatory was Physics Professor Johan Jakob Nervander (1805-1848). He was a famous person of the Finnish scientific, academic and cultural community in the early decades of the 19th century. Finland was an autonomously part of the Russian Empire from 1809 to 1917, but the observatory remained organizationally under the University of Helsinki, independent of Russian scientific institutions, and funded by the Finnish Government. Throughout the late-19th century the Meteorological Institute was responsible of nationwide meteorological, hydrological and marine observations and research. The observatory was transferred to the Finnish Society of Sciences and Letters under the name the Central Meteorological Institute in 1881. The focus of the work carried out in the Institute was changed gradually towards meteorology. Magnetic measurements were still continued but in a lower level of importance. The culmination of Finnish geophysical achievements in the 19th century was the participation to the International Polar Year programme in 1882-1883 by setting up a full-scale meteorological and magnetic observatory in Sodankylä, Lapland.

EARLY IMPACT MELTING AND SPACE EXPOSURE HISTORY OF THE PAT91501 LCHONDRITE

NASA Technical Reports Server (NTRS)

Bogard, Donald D.; Garrison, D. H.; Herzog, G. F.; Xue, S.; Klein, J.; Middleton, R.

2004-01-01

Collisions probably occurred frequently in the early history of the asteroid belt. Their effects, which should be recorded in meteorites, must have included heating and melting along with shock alteration of mineral textures. Some non-chondritic meteorite types e.g., eucrites and IIE and IAB irons - do indeed give evidence of extensive impact heating more than 3.4 Gyr ago. The ordinary chondrites, in contrast, show little evidence of early impact heating. The Ar-Ar and Rb-Sr ages of ordinary chondrites that experienced intense shock are for the most part relatively young, many less than 1.5 Gyr. The numerous L-chondrites with Ar- Ar ages clustering near 0.5 Gy are a well-known example. One of them, the 105-kg Chico Lchondrite, shows the effects of unusually intense heating. It is approximately 60% impact melt and likely formed as a dyke beneath a large crater when the L-chondrite parent body underwent a very large impact approximately 0.5 Gyr ago. In rare instances, older shock dates are indicated for ordinary chondrites. Dixon et al show early impact resetting of Ar-Ar ages of a few LL-chondrites including MIL 99301 at 4.23 0.03 Gyr, but in none of these stones did shock lead to extensive melting. As of 2003, searches for chondritic melts attributable to early shock had turned up only the Shaw L-chondrite, which has an Ar-Ar age of approximately 4.42 Gyr. PAT91501 is an 8.55-kg L-chondrite containing vesicles and metal-troilite nodules. It is a unique, near-total impact melt, unshocked, depleted in siderophile and chalcophile elements, and contains only approximately 10% relic chondritic material. The authors conclude that PAT91501 crystallized rapidly and from a much more homogeneous melt than did Shaw. They suggest that PAT resembles Chico and likely formed as an impact melt vein within an impact crater. To define the history of PAT, we have determined its Ar-39-Ar-40 age and measured several radioactive and stable nuclides produced during its space exposure to

Early volcanic history of the Rabaul area

NASA Astrophysics Data System (ADS)

McKee, Chris O.; Duncan, Robert A.

2016-04-01

We conducted an extensive program of 40Ar-39Ar age determinations on a suite of 27 volcanic rock samples from key stratigraphic units at Rabaul, Papua New Guinea in order to improve understanding of the early eruption history of the multiple volcanic systems present in the area. Analyses of whole rock, plagioclase and groundmass separates yielded statistically significant ages for 24 samples. Replicate analyses (groundmass, plagioclase) for 17 of the samples provided concordant ages. The oldest systems in the Rabaul area (>1 Ma to ≈300 ka) are in the south, associated with the caldera-like Varzin Depression, and in the north, at the stratovolcanoes Watom and Tovanumbatir. The earliest known activity of the Rabaul system occurred between about 330 and 200 ka and involved emplacement of lava flows and scoria deposits. Major explosive activity at the Rabaul system commenced at about 200 ka and produced a sequence of dacitic ignimbrites that culminated with the emplacement of the large-volume Malaguna Pyroclastics at about 160 ka. Calderas may have been formed as a consequence of the large volumes of tephra produced during some of these eruptions. Products of the early activity are found in the northern and northeastern walls of Rabaul Caldera and on the northeastern flank of Tovanumbatir. This leads to the conclusion that the source of the early activity at Rabaul probably was located in the northern part of the present caldera complex. A shift in the focus of activity at the Rabaul system took place between about 160 and 125 ka. All of the younger (<125 ka) major pyroclastic formations, including the Karavia Welded Tuff, the Barge Tunnel Ignimbrite and the Latlat Pyroclastics, which make up the bulk of the exposure in the southern and western walls of Rabaul Caldera, were erupted from a source or sources in the south-central part of the complex. The stratovolcanoes Palangiangia and Kabiu, which flank the northeastern part of the complex, had commenced activity by

CHROMOSOME 11 ABERRATIONS IN SMALL COLONY L5178Y TK-/-MUTANTS EARLY IN THEIR CLONAL HISTORY

EPA Science Inventory

The authors have developed a cytogenetic technique that allows observation of chromosome rearrangements associated with TK-/- mutagenesis of the L5178Y/TK+/-3.7.2C cell line early in mutant clonal history. For a series of mutagenic treatments they show that the major proportion (...

Pyroxenes in Serra de Mage - Cooling history in comparison with Moama and Moore County

NASA Technical Reports Server (NTRS)

Harlow, G. E.; Prinz, M.; Nehru, C. E.; Taylor, G. J.; Keil, K.

1979-01-01

Thin sections and single grains of pyroxenes from the Serra de Mage feldspar cumulate eucrites were studied by X-ray crystallography, electron microprobe and optical techniques. It was concluded that the pyroxene crystallized as pigeonite. On cooling augite was exsolved along (001) and inverted to hypersthene, with exsolution of (100) augite from hypersthene during continued slow cooling. The estimated original bulk composition of the pigeonite pyroxene is Wo10En51Fs39. The compositional data, textural relations, and existence of P2 sub 1 ca hypersthene suggest very low cooling (about 0.0004 deg C/year) below 800 deg. The Serra de Mage augite lamellae were found to be as thick or thicker than those of Moore County and Moama meteorites.

The known knowns, the known unknowns, and beyond: early life history perspective for the Laurentian Great Lakes

EPA Science Inventory

Early life history research has been crucial for understanding and managing fisheries in the Laurentian Great Lakes and beyond. Much is known about spawning sites, temperatures at spawning, incubation periods, spawning substrates, and other factors surrounding reproduction for ma...

Industrial Process Cooling Towers: National Emission Standards for Hazardous Air Pollutants

EPA Pesticide Factsheets

Standards limiting discharge of chromium compound air emissions from industrial process cooling towers (IPCT's). Includes rule history, Federal Registry citations, implementation information and additional resources.

Reflexivity, the role of history, and the case of mesmerism in early Victorian Britain.

PubMed

Lamont, Peter

2010-11-01

As part of a wider argument that history is essential to psychological understanding because of the reflexive nature of psychological knowledge, this article examines the case of mesmerism in early Victorian Britain as an example of how psychological knowledge is both constructive and constructed. It is argued that the shift from "mesmerism" to "hypnotism" was a change in understanding that created a new kind of psychological experience. It is also argued that demonstrations of mesmerism, far from being self-evident facts, could be framed as evidence either for or against the central claims of mesmerism. It is concluded that the case of mesmerism in early Victorian Britain provides a further example of the need for historical understanding within Psychology.

Cooling metals to the microkelvin regime, then and now

NASA Astrophysics Data System (ADS)

Pickett, G. R.

2000-05-01

Better understanding of the behaviour of materials and the techniques of nuclear cooling, gained in recent years, now allows us to cool metallic samples to the microkelvin regime, with hold times at the higher temperatures of tens of hours. In the early days of nuclear cooling when sources of heat leaks were hardly understood, such performance would have appeared an impossible dream. However, we are now at the point where solid state experiments can be realistically contemplated in the sub- 10 μK regime.

Density-dependent coral recruitment displays divergent responses during distinct early life-history stages

PubMed Central

Evensen, Nicolas R.; Gómez-Lemos, Luis A.; Babcock, Russell C.

2017-01-01

Population growth involves demographic bottlenecks that regulate recruitment success during various early life-history stages. The success of each early life-history stage can vary in response to population density, interacting with intrinsic (e.g. behavioural) and environmental (e.g. competition, predation) factors. Here, we used the common reef-building coral Acropora millepora to investigate how density-dependence influences larval survival and settlement in laboratory experiments that isolated intrinsic effects, and post-settlement survival in a field experiment that examined interactions with environmental factors. Larval survival was exceptionally high (greater than 80%) and density-independent from 2.5 to 12 days following spawning. By contrast, there was a weak positive effect of larval density on settlement, driven by gregarious behaviour at the highest density. When larval supply was saturated, settlement was three times higher in crevices compared with exposed microhabitats, but a negative relationship between settler density and post-settlement survival in crevices and density-independent survival on exposed surfaces resulted in similar recruit densities just one month following settlement. Moreover, a negative relationship was found between turf algae and settler survival in crevices, whereas gregarious settlement improved settler survival on exposed surfaces. Overall, our findings reveal divergent responses by coral larvae and newly settled recruits to density-dependent regulation, mediated by intrinsic and environmental interactions. PMID:28573015

Hydration and Cooling Practices Among Farmworkers in Oregon and Washington

PubMed Central

Bethel, Jeffrey W.; Spector, June T.; Krenz, Jennifer

2018-01-01

Objectives Although recommendations for preventing occupational heat-related illness among farmworkers include hydration and cooling practices, the extent to which these recommendations are universally practiced is unknown. The objective of this analysis was to compare hydration and cooling practices between farmworkers in Oregon and Washington. Methods A survey was administered to a purposive sample of Oregon and Washington farmworkers. Data collected included demographics, work history and current work practices, hydration practices, access and use of cooling measures, and headwear and clothing worn. Results Oregon farmworkers were more likely than those in Washington to consume beverages containing sugar and/or caffeine. Workers in Oregon more frequently reported using various cooling measures compared with workers in Washington. Availability of cooling measures also varied between the two states. Conclusions These results highlight the large variability between workers in two states regarding access to and use of methods to stay cool while working in the heat. PMID:28402203

Contrasting cooling and exhumation histories of tectonic blocks in the eastern part of the Eastern Alps and its possible relationships with lithospheric dynamics

NASA Astrophysics Data System (ADS)

Wölfler, Andreas; Glotzbach, Christoph

2017-04-01

In the European Alps two fundamental changes in the lithospheric structure controlled the geodynamic evolution of the orogen: (1) Late Eocene to Early Oligocene rupturing of the European slab and (2) Early Miocene change in subduction polarity between the Western and Eastern Alps. In particular, the eastern part of the Eastern Alps is a key area which will provide both, information about the surface response to the Eocene/Oligocene slab breakoff and the response to a proposed isostatic rebound due to slab detachment of the European lithosphere in the Miocene (Handy et al., 2015). The eastern part of the Eastern Alps is characterized by fault-bounded blocks with different thermochronological ages, mean elevations and hillslope angles, indicating a variable spatial and temporal evolution throughout the Cenozoic era. The topographic pattern of the study area can be described in terms of (1) high relief with a rugged surface and steep slopes in the Niedere Tauern and (2) lower relief and distinctly smoother topography in the Seckauer Tauern, the Gurktal, Saualpe and Koralpe blocks. Generally, tectonic blocks with higher relief and rugged topography display the youngest apatite fission track (AFT) and apatite (U-Th)/He data (AHe); the Niedere Tauern concurs with middle Miocene AFT and late Miocene/Pliocene AHe ages (Wölfler et al., 2016). The other tectonic blocks generally show Eocene to Oligocene AFT ages (Wölfler et al., 2016 and references therein) and Oligocene to early Miocene AHe ages (Legrain et al., 2014, own preliminary work). New AFT and AHe data from the Gurktal block and Seckauer Tauern indicate that substantial parts of the study area where at near-surface conditions since the Eocene and Oligocene. Thermal history models suggest fast cooling through the AFT and AHe closure temperatures in the Oligocene as a possible response to slab breakoff that was followed by thermal stagnation until the present. In contrast, the neighboring Niedere Tauern experienced

Constraining the thermal history of the North American Midcontinent Rift System using carbonate clumped isotopes and organic thermal maturity indices

USGS Publications Warehouse

Gallagher, Timothy M.; Sheldon, Nathan D.; Mauk, Jeffrey L.; Petersen, Sierra V.; Gueneli, Nur; Brocks, Jochen J.

2017-01-01

The Midcontinent Rift System (MRS) is a Late Mesoproterozoic (∼1.1 Ga) sequence of volcanic and sedimentary rocks exposed in the Lake Superior Region of North America. The MRS continues to be the focus of much research due to its economic mineral deposits as well as its archive of Precambrian life and tectonic processes. In order to constrain the post-depositional thermal history of the MRS, samples were analyzed for carbonate clumped isotope composition and organic thermal maturity. Clumped isotope values from sedimentary/early-diagenetic samples were partially reset during burial to temperatures between 68 and 75 °C. Solid-state reordering models indicate that maximum burial temperatures of 125–155 °C would reset the clumped isotope values to the observed temperature range prior to the onset of regional cooling and uplift. Clumped isotope results from late-stage veins in the White Pine Mine encompass a greater temperature range (49–116 °C), indicative of spatially variable hydrothermal activity and vein emplacement after burial temperatures fell below 100 °C during regional cooling and uplift. Clumped isotope and organic thermal maturity data do not indicate significant spatial differences in thermal history along the MRS. Observed variability in bulk organic matter composition and biomarker indices are therefore more likely a result of shifts in primary productivity or early-degradation processes. These results demonstrate that the MRS experienced a spatially consistent, relatively mild thermal history (125–155 °C) and is therefore a valuable archive for understanding the Late Mesoproterozoic environment.

TEACHERS' GUIDES. WORLD HISTORY FOR THE ACADEMICALLY TALENTED. ADVANCED PLACEMENT EUROPEAN HISTORY.

ERIC Educational Resources Information Center

AUGSPURGER, EVERETT F.; AND OTHERS

PREPARED BY TEACHERS AND SUPERVISORS WORKING WITH A 2-YEAR DEMONSTRATION PROJECT, THIS DOCUMENT CONTAINS GUIDES FOR A WORLD HISTORY COURSE (PREHISTORY TO EARLY 20TH CENTURY) FOR THE GIFTED AND AN ADVANCED PLACEMENT COURSE IN EUROPEAN HISTORY (ANCIENT CIVILIZATION TO EARLY 20TH CENTURY). STUDENTS ARE EXPECTED TO STUDY HISTORICAL ISSUES AND DEVELOP…

The early history of ideas on brief interventions for alcohol

PubMed Central

McCambridge, Jim; Cunningham, John A

2014-01-01

Aims This study explores the early development of brief interventions for alcohol using a history of ideas approach with a particular focus on intervention content. Methods The source publications of the key primary studies published from approximately 1962 to 1992 were examined, followed by a brief review of the earliest reviews in this field. These studies were placed in the context of developments in alcohol research and in public health. Results After early pioneering work on brief interventions, further advances were not made until thinking about alcohol problems and their treatment, most notably on controlled drinking, along with wider changes in public health, created new conditions for progress. There was then a golden era of rapid advance in the late 1980s and early 1990s, when preventing the development of problem drinking became important for public health reasons, in addition to helping already problematic drinkers. Many research challenges identified at that time remain to be met. The content of brief interventions changed over the period of study, although not in ways well informed by research advances, and there were also obvious continuities, with a renewed emphasis on the facilitation of self-change being one important consequence of the development of internet applications. Conclusions Ideas about brief interventions have changed in important ways. Brief interventions have been studied with different populations of drinkers, with aims embracing both individual and population-level perspectives, and without well-specified contents. The brief intervention field is an appropriate target for further historical investigations, which may help thinking about addressing alcohol and other problems. PMID:24354855

Cooling of Accretion-Heated Neutron Stars

NASA Astrophysics Data System (ADS)

Wijnands, Rudy; Degenaar, Nathalie; Page, Dany

2017-09-01

We present a brief, observational review about the study of the cooling behaviour of accretion-heated neutron stars and the inferences about the neutron-star crust and core that have been obtained from these studies. Accretion of matter during outbursts can heat the crust out of thermal equilibrium with the core and after the accretion episodes are over, the crust will cool down until crust-core equilibrium is restored. We discuss the observed properties of the crust cooling sources and what has been learned about the physics of neutron-star crusts. We also briefly discuss those systems that have been observed long after their outbursts were over, i.e, during times when the crust and core are expected to be in thermal equilibrium. The surface temperature is then a direct probe for the core temperature. By comparing the expected temperatures based on estimates of the accretion history of the targets with the observed ones, the physics of neutron-star cores can be investigated. Finally, we discuss similar studies performed for strongly magnetized neutron stars in which the magnetic field might play an important role in the heating and cooling of the neutron stars.

Experimental cooling during incubation leads to reduced innate immunity and body condition in nestling tree swallows.

PubMed

Ardia, Daniel R; Pérez, Jonathan H; Clotfelter, Ethan D

2010-06-22

Nest microclimate can have strong effects that can carry over to later life-history stages. We experimentally cooled the nests of tree swallows (Tachycineta bicolor). Females incubating in cooled nests reduced incubation time and allowed egg temperatures to drop, leading to extended incubation periods. We partially cross-fostered nestlings to test carry-over effects of cooling during incubation on nestling innate constitutive immunity, assessed through bacteria killing ability (BKA) of blood. Nestlings that had been cooled as eggs showed a lower ability to kill bacteria than control nestlings, regardless of the treatment of their foster mother. However, there was no effect of treatment of rearing females on nestling BKA in control nestlings, even though cooled females made significantly fewer feeding visits than did control females. This suggests that the effect of cooling occurred during incubation and was not due to carry-over effects on nestling condition. Nestlings that were exposed to experimental cooling as embryos had lower residual body mass and absolute body mass at all four ages measured. Our results indicate that environmental conditions and trade-offs experienced during one stage of development can have important carry-over effects on later life-history stages.

[Evaluation of quality of life in school children with a history of early severe malnutrition].

PubMed

De Grandis, E S; Armelini, P A; Cuestas, E

2014-12-01

Severe malnutrition in young children may lead to long-term complications, in particular learning and psychosocial disorders linked to health related quality of life (HRQOL). The aim of this study was to evaluate HRQOL in children whit a history of severe malnutrition before 2 years of life, expecting to find lower scores in these patients. A comparative study was performed on schoolchildren between 5 and 12 years with a history of early severe malnutrition, excluding those with chronic diseases. The Controls were healthy siblings of patients. The sample size was estimated as 26 subjects per group (Total=52). Sociodemographic variables were recorded and the HRQOL was assessed with PedsQL4.0. Chi square and Student t test were applied. Significance level: P<.05. A total of 25 patients and 28 controls were studied. The HRQOL scores obtained from PedsQL for children with history of malnutrition, compared with their healthy siblings, were: Total: 80.82±1.94 vs 89.18±1.84 P<.0001), physical health/dimension: 87.75±3.37 vs 94.75±1.87 (P<.0001), psychosocial health: 77.77±2.90 vs 86.57±1.42 (P<.0001), emotional dimension: 67.80±4.40 vs 78.75±2.96 (P<.0001), social dimension: 88.80±3.05 vs 95.71±1.52 (P<.0001), and school dimension: 74.58±3.80 vs 85.00±3.51 (P<.0001). Patients with a history of early severe malnutrition, showed significantly lower HRQOL scores compared with controls. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

Droplet Impact Sub-cavity Histories and PDPA Spray Experiments for Spray Cooling Modeling

NASA Astrophysics Data System (ADS)

Hillen, Nicholas Lee

Spray cooling is a topic of current interest for its ability to uniformly remove high levels of waste heat from densely packed microelectronics. It has demonstrated the ability to achieve very high heat fluxes, up to 500 W/cm2 with water as the coolant, making it an attractive active thermal management tool. Full Computational Fluid Dynamic (CFD) simulations of spray cooling are infeasible due to the complexity of the spray (drops fluxes of 106 drops/cm2-sec) and heater surface physics requiring impractical resources. Thus a Monte-Carlo (MC) spray cooling simulation model based on empirical data is under development to serve as a cost effective design tool. The initial MC model shows promise, but it lacks additional physics necessary to predict accurate heat fluxes based on nozzle conditions and heated surface geometry. This work reports spray and single drop experiments with the goal of computing the volume beneath a droplet impact cavity (the sub-cavity volume) created by a single impinging droplet on an initial liquid layer. A Phase Doppler Particle Analyzer (PDPA) was utilized to characterize a spray of interest in terms of integrated global Weber, Reynolds, and Froude numbers for varying flow conditions. Results showed that the spray droplet diameters decreased and velocities increased with increasing nozzle gage pressure. A relevant test plan for the single drop experiments has been created from the measured PDPA spray profiles combined with residual spray film thickness measurements from literature resulting in: 140≤We≤1,000, 1,200≤ Re≤3,300, and 0.2≤h0*≤1.0. Froude numbers were not able to be matched for the current single drop experiments (spray: 32,800≤Fr≤275,000). Liquid film thicknesses under the cavity formed by a single droplet have been measured versus radius and time via a non-contact optical thickness sensor for the selected range of dimensionless numbers (We, Re, and h0*). Sub-cavity radius histories have also been analyzed

Multiplicity of the Galactic Senior Citizens: A High-resolution Search for Cool Subdwarf Companions

NASA Astrophysics Data System (ADS)

Ziegler, Carl; Law, Nicholas M.; Baranec, Christoph; Riddle, Reed L.; Fuchs, Joshua T.

2015-05-01

Cool subdwarfs are the oldest members of the low-mass stellar population. Mostly present in the galactic halo, subdwarfs are characterized by their low-metallicity. Measuring their binary fraction and comparing it to solar-metallicity stars could give key insights into the star formation process early in the Milky Way’s history. However, because of their low luminosity and relative rarity in the solar neighborhood, binarity surveys of cool subdwarfs have suffered from small sample sizes and incompleteness. Previous surveys have suggested that the binary fraction of red subdwarfs is much lower than for their main-sequence cousins. Using the highly efficient Robo-AO system, we present the largest high-resolution survey of subdwarfs, sensitive to angular separations (ρ ≥slant 0.″ 15) and contrast ratios ({Δ }{{m}i} ≤slant 6) invisible in past surveys. Of 344 target cool subdwarfs, 43 are in multiple systems, 19 of which are newly discovered, for a binary fraction of 12.5 ± 1.9%. We also discovered seven triple star systems for a triplet fraction of 2.0 ± 0.8%. Comparisons to similar surveys of solar-metallicity dwarf stars gives a ∼3σ disparity in luminosity between companion stars, with subdwarfs displaying a shortage of low-contrast companions. We also observe a lack of close subdwarf companions in comparison to similar-mass dwarf multiple systems.

Social Confidence in Early Adulthood Among Young People With and Without a History of Language Impairment

PubMed Central

Durkin, Kevin; Toseeb, Umar; Botting, Nicola; Pickles, Andrew

2017-01-01

Purpose The purposes of this study were to test the predictions that lower self-esteem and higher shyness in individuals with a history of language impairment (LI) would continue from adolescence into early adulthood and that those with LI would have lower social self-efficacy in early adulthood. Method Participants were young people with a history of LI and a comparison group of age-matched peers. Both groups were tested at ages 17 and 24 years. Participants completed measures of language ability, nonverbal IQ, shyness, global self-esteem, and (at age 24 years only) social self-efficacy. Results Young adults with LI scored lower than age-matched peers on self-esteem, higher on shyness, and lower on social self-efficacy (medium to large effect sizes). In line with expectations, in the group with LI, language ability in adolescence predicted shyness in young adulthood, which, in turn, was negatively associated with self-esteem. There was also a direct association between language ability in adolescence and self-esteem in young adulthood. Conclusions Young people with a history of LI are likely to be entering adulthood less socially confident than their peers. Interventions may be desirable for young adults with LI, and the present findings indicate social self-efficacy as a key area of social confidence that calls for practitioners' attention. PMID:28586830

Hydrogen-nitrogen greenhouse warming in Earth's early atmosphere.

PubMed

Wordsworth, Robin; Pierrehumbert, Raymond

2013-01-04

Understanding how Earth has sustained surface liquid water throughout its history remains a key challenge, given that the Sun's luminosity was much lower in the past. Here we show that with an atmospheric composition consistent with the most recent constraints, the early Earth would have been significantly warmed by H(2)-N(2) collision-induced absorption. With two to three times the present-day atmospheric mass of N(2) and a H(2) mixing ratio of 0.1, H(2)-N(2) warming would be sufficient to raise global mean surface temperatures above 0°C under 75% of present-day solar flux, with CO(2) levels only 2 to 25 times the present-day values. Depending on their time of emergence and diversification, early methanogens may have caused global cooling via the conversion of H(2) and CO(2) to CH(4), with potentially observable consequences in the geological record.

Simulation of Cooling Rate Effects on Ti-48Al-2Cr-2Nb Crack Formation in Direct Laser Deposition

NASA Astrophysics Data System (ADS)

Yan, Lei; Li, Wei; Chen, Xueyang; Zhang, Yunlu; Newkirk, Joe; Liou, Frank; Dietrich, David

2017-03-01

Transient temperature history is vital in direct laser deposition (DLD) as it reveals the cooling rate at specific temperatures. Cooling rate directly relates to phase transformation and types of microstructure formed in deposits. In this paper, finite element analysis simulation was employed to study the transient temperature history and cooling rate at different experimental setups in the Ti-48Al-2Cr-2Nb DLD process. An innovative prediction strategy was developed to model with a moving Gaussian distribution heat source and element birth and death technology in ANSYS®, and fabricate crack-free deposits. This approach helps to understand and analyze the impact of cooling rate and also explain phase information gathered from x-ray diffraction.

The early history of ideas on brief interventions for alcohol.

PubMed

McCambridge, Jim; Cunningham, John A

2014-04-01

This study explores the early development of brief interventions for alcohol using a history of ideas approach with a particular focus on intervention content. The source publications of the key primary studies published from approximately 1962 to 1992 were examined, followed by a brief review of the earliest reviews in this field. These studies were placed in the context of developments in alcohol research and in public health. After early pioneering work on brief interventions, further advances were not made until thinking about alcohol problems and their treatment, most notably on controlled drinking, along with wider changes in public health, created new conditions for progress. There was then a golden era of rapid advance in the late 1980s and early 1990s, when preventing the development of problem drinking became important for public health reasons, in addition to helping already problematic drinkers. Many research challenges identified at that time remain to be met. The content of brief interventions changed over the period of study, although not in ways well informed by research advances, and there were also obvious continuities, with a renewed emphasis on the facilitation of self-change being one important consequence of the development of internet applications. Ideas about brief interventions have changed in important ways. Brief interventions have been studied with different populations of drinkers, with aims embracing both individual and population-level perspectives, and without well-specified contents. The brief intervention field is an appropriate target for further historical investigations, which may help thinking about addressing alcohol and other problems. © 2013 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

Active cooling from the sixties to NASP

NASA Technical Reports Server (NTRS)

Kelly, H. Neale; Blosser, Max L.

1992-01-01

Vehicles, such as the X-15 or National Aero-Space Plane, traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of this paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years--from early engine structures, which were intended to be tested on the X-15, to structural--are described. Many of the lessons learned from these research efforts are presented.

Paleofluid-flow circulation within a Triassic rift basin: Evidence from oil inclusions and thermal histories

USGS Publications Warehouse

Tseng, H.-Y.; Burruss, R.C.; Onstott, T.C.; Omar, G.

1999-01-01

The migration of subsurface fluid flow within continental rift basins has been increasingly recognized to significantly affect the thermal history of sediments and petroleum formation. To gain insight into these paleofluid flow effects, the thermal history of the Taylorsville basin in Virginia was reconstructed from fluid-inclusion studies, apatite fission-track data, and vitrinite reflectance data. Models of thermal history indicate that the basin was buried to the thermal maximum at 200 Ma; a cooling event followed during which the eastern side of the basin cooled earlier and faster than the western side, suggesting that there was a differential uplift and topographically driven fluid flow. This hypothesis is supported by analyses of secondary oil and aqueous inclusions trapped in calcite and quartz veins during the uplift stage. Gas chromatograms of inclusion oils exhibit variable but extensive depletion of light molecular-weight hydrocarbons. The relative abundance of n-alkanes, petrographic observations, and the geological data indicate that the alteration process on these inclusion oils was probably neither phase separation nor biodegradation, but water washing. Water:oil ratios necessary to produce the observed alteration are much greater than 10000:1. These exceedingly high ratios are consistent with the migration of inclusion oils along with fluid flow during the early stages of basin evolution. The results provide significant evidence about the role of a subsurface flow system in modifying the temperature structure of the basin and the composition of petroleum generated within the basin.

Turbine airfoil cooling system with cooling systems using high and low pressure cooling fluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marsh, Jan H.; Messmann, Stephen John; Scribner, Carmen Andrew

A turbine airfoil cooling system including a low pressure cooling system and a high pressure cooling system for a turbine airfoil of a gas turbine engine is disclosed. In at least one embodiment, the low pressure cooling system may be an ambient air cooling system, and the high pressure cooling system may be a compressor bleed air cooling system. In at least one embodiment, the compressor bleed air cooling system in communication with a high pressure subsystem that may be a snubber cooling system positioned within a snubber. A delivery system including a movable air supply tube may be usedmore » to separate the low and high pressure cooling subsystems. The delivery system may enable high pressure cooling air to be passed to the snubber cooling system separate from low pressure cooling fluid supplied by the low pressure cooling system to other portions of the turbine airfoil cooling system.« less

FORTRAN 77 programs for conductive cooling of dikes with temperature-dependent thermal properties and heat of crystallization

USGS Publications Warehouse

Delaney, P.T.

1988-01-01

Temperature histories obtained from transient heat-conduction theory are applicable to most dikes despite potential complicating effects related to magma flow during emplacement, groundwater circulation, and metamorphic reaction during cooling. Here. machine-independent FORTRAN 77 programs are presented to calculate temperatures in and around dikes as they cool conductively. Analytical solutions can treat thermal-property contrasts between the dike and host rocks, but cannot address the release of magmatic heat of crystallization after the early stages of cooling or the appreciable temperature dependence of thermal conductivity and diffusivity displayed by most rock types. Numerical solutions can incorporate these additional factors. The heat of crystallization can raise the initial temperature at the dike contact, ??c1, about 100??C above that which would be estimated if it were neglected, and can decrease the rate at which the front of solidified magma moves to the dike center by a factor of as much as three. Thermal conductivity and diffusivity of rocks increase with decreasing temperature and, at low temperatures, these properties increase more if the rocks are saturated with water. Models that treat these temperature dependencies yield estimates of ??c1 that are as much as 75??C beneath those which would be predicted if they were neglected. ?? 1988.

Holocene temperature history of northern Iceland inferred from subfossil midges

NASA Astrophysics Data System (ADS)

Axford, Yarrow; Miller, Gifford H.; Geirsdóttir, Áslaug; Langdon, Peter G.

2007-12-01

The Holocene temperature history of Iceland is not well known, despite Iceland's climatically strategic location at the intersection of major surface currents in the high-latitude North Atlantic. Existing terrestrial records reveal spatially heterogeneous changes in Iceland's glacier extent, vegetation cover, and climate over the Holocene, but these records are temporally discontinuous and mostly qualitative. This paper presents the first quantitative estimates of temperatures throughout the entire Holocene on Iceland. Mean July temperatures are inferred based upon subfossil midge (Chironomidae) assemblages from three coastal lakes in northern Iceland. Midge data from each of the three lakes indicate broadly similar temperature trends, and suggest that the North Icelandic coast experienced relatively cool early Holocene summers and gradual warming throughout the Holocene until after 3 ka. This contrasts with many sites on Iceland and around the high-latitude Northern Hemisphere that experienced an early to mid-Holocene "thermal maximum" in response to enhanced summer insolation forcing. Our results suggest a heightened temperature gradient across Iceland in the early Holocene, with suppressed terrestrial temperatures along the northern coastal fringe, possibly as a result of sea surface conditions on the North Iceland shelf.

Thermal history and differential exhumation across the Eastern Musgrave Province, South Australia: Insights from low-temperature thermochronology

NASA Astrophysics Data System (ADS)

Glorie, Stijn; Agostino, Kate; Dutch, Rian; Pawley, Mark; Hall, James; Danišík, Martin; Evans, Noreen J.; Collins, Alan S.

2017-04-01

Multi-method geo- and thermochronological data obtained for Palaeo- and Mesoproterozoic granitoids traversing the main structural architecture of the eastern Musgrave Province within South Australia reveal multiphase cooling histories. Apatite U-Pb dating on six samples yield consistent ages of 1075-1025 Ma, suggesting a thermal reset coinciding with mantle-derived magmatism of the greater Warakurna Large Igneous Province ( 1080-1040 Ma). Apatite fission track (AFT) analysis indicate that four discrete thermal events affected the study area, inducing cooling through the AFT partial annealing zone ( 60-120 °C), supported by apatite and zircon (U-Th-Sm)/He data. Late Neoproterozoic cooling from deep crustal levels to temperatures < 200 °C was discerned, which is thought to be related to exhumation and denudation during the Petermann Orogeny. Subsequent cooling events at 450-400 Ma (Silurian-Devonian) and 310-290 Ma (Late Carboniferous) are interpreted to represent exhumation associated with the Alice Springs Orogeny. The latter event exhumed the sampled plutons to shallow crustal depths. An additional Triassic - early Jurassic thermal event, likely recording elevated geothermal gradients at that time, was observed throughout the study area, however, more data is needed to further support this interpretation. The high sample density across the structural architecture of the study area furthermore reveals patterns of fault reactivation and resulting differential exhumation, indicating shallower exhumation levels in the centre and deeper exhumation towards the margins of the sampled transect. The observed differential exhumation patterns match with existing seismic data and fit a model of an inverted graben system for the Phanerozoic evolution of the eastern Musgraves. The results highlight a complex Phanerozoic thermal history for the eastern Musgraves and help to elucidate the poorly appreciated tectonic evolution of inland Australia. This study further demonstrates

Dwarf galaxy populations in present-day galaxy clusters - II. The history of early-type and late-type dwarfs

NASA Astrophysics Data System (ADS)

Lisker, Thorsten; Weinmann, Simone M.; Janz, Joachim; Meyer, Hagen T.

2013-06-01

How did the dwarf galaxy population of present-day galaxy clusters form and grow over time? We address this question by analysing the history of dark matter subhaloes in the Millennium II cosmological simulation. A semi-analytic model serves as the link to observations. We argue that a reasonable analogue to early morphological types or red-sequence dwarf galaxies are those subhaloes that experienced strong mass-loss, or alternatively those that have spent a long time in massive haloes. This approach reproduces well the observed morphology-distance relation of dwarf galaxies in the Virgo and Coma clusters, and thus provides insight into their history. Over their lifetime, present-day late types have experienced an amount of environmental influence similar to what the progenitors of dwarf ellipticals had already experienced at redshifts above 2. Therefore, dwarf ellipticals are more likely to be a result of early and continuous environmental influence in group- and cluster-size haloes, rather than a recent transformation product. The observed morphological sequences of late-type and early-type galaxies have developed in parallel, not consecutively. Consequently, the characteristics of today's late-type galaxies are not necessarily representative for the progenitors of today's dwarf ellipticals. Studies aiming to reproduce the present-day dwarf population thus need to start at early epochs, model the influence of various environments, and also take into account the evolution of the environments themselves.

Abundances of volatile-bearing phases in carbonaceous chondrites and cooling rates of meteorites based on cation ordering of orthopyroxenes

NASA Technical Reports Server (NTRS)

Ganguly, Jibamitra

1989-01-01

Results of preliminary calculations of volatile abundances in carbonaceous chondrites are discussed. The method (Ganguly 1982) was refined for the calculation of cooling rate on the basis of cation ordering in orthopyroxenes, and it was applied to the derivation of cooling rates of some stony meteorites. Evaluation of cooling rate is important to the analysis of condensation, accretion, and post-accretionary metamorphic histories of meteorites. The method of orthopyroxene speedometry is widely applicable to meteorites and would be very useful in the understanding of the evolutionary histories of carbonaceous chondrites, especially since the conventional metallographic and fission track methods yield widely different results in many cases. Abstracts are given which summarize the major conclusions of the volatile abundance and cooling rate calculations.

Active cooling from the sixties to NASP

NASA Technical Reports Server (NTRS)

Kelly, H. Neale; Blosser, Max L.

1994-01-01

Vehicles, such as the X-15 or the National Aerospace Plane (NASP), traveling at hypersonic speeds through the earth's atmosphere experience aerodynamic heating. The heating can be severe enough that a thermal protection system is required to limit the temperature of the vehicle structure. Although several categories of thermal protection systems are mentioned briefly, the majority of the present paper describes convectively cooled structures for large areas. Convective cooling is a method of limiting structural temperatures by circulating a coolant through the vehicle structure. Efforts to develop convectively cooled structures during the past 30 years, from early engine structures which were intended to be tested on the X-15 to structural panels fabricated and tested under the NASP program, are described. Many of the lessons learned from these research efforts are presented.

The relevance of the early history of probability theory to current risk assessment practices in mental health care.

PubMed

Large, Matthew

2013-12-01

Probability theory is at the base of modern concepts of risk assessment in mental health. The aim of the current paper is to review the key developments in the early history of probability theory in order to enrich our understanding of current risk assessment practices.

Retaining Meanings of Quality in Australian Early Childhood Education and Care Policy History: Perspectives from Policy Makers

ERIC Educational Resources Information Center

Logan, Helen

2018-01-01

This paper presents lesser known accounts from policy makers whose experiences as elite informants span 40 or so years in Australian early childhood education and care (ECEC) policy history between 1972 and 2009. Drawing on a post-structuralist theoretical frame, this paper employs a Foucauldian-influenced approach to discourse analysis. Given the…

Cooling strategies for brazilian flounder Paralichthys orbignyanus embryos.

PubMed

Varela, A S; Cardoso, T F; Fernandes E Silva, E; Goularte, K L; Okamoto, M H; Sampaio, L A; Jardim, R D; Corcini, C D

Paralichthys orbignyanus is the species of the greatest potential for marine and estuarine fish farming in southern Brazil. Consequently, embryo cryopreservation becomes an important tool for increasing their production. To evaluate the effects of cooling protocols on the viability of embryos of P. orbignyanus at two stages of development (neurula and early differentiation of the tail). Control embryos were maintained at 23 degree C and treated embryos were cooled to 15 degree C, 10 degree C and 5 degree C at rapid, moderate and slow cooling rates. Then embryos were maintained at these different temperatures for 30, 60 and 90 min and the loss of viability assessed as hatching rates (HR) and morphologically normal larvae (MNL). The average HR for embryos following cooling was higher for those at the tail stage compared to the neurula stage (P<0.05). In both stages there was no statistical difference between the HR of control embryos and those exposed to rapid cooling. Also for tail stage embryos, there was no difference between MNL of control and rapidly cooled embryos. As first steps in the development of cryopreservation methods for P. orbignyanus embryos, the use of a rapid cooling and holding at 5 degree C for 30 min are recommended.

The accretion and impact history of the ordinary chondrite parent bodies

NASA Astrophysics Data System (ADS)

Blackburn, Terrence; Alexander, Conel M. O'D.; Carlson, Richard; Elkins-Tanton, Linda T.

2017-03-01

A working timeline for the history of ordinary chondrites includes chondrule formation as early as 0-2 Ma after our Solar System's earliest forming solids (CAIs), followed by rapid accretion into undifferentiated planetesimals that were heated internally by 26Al decay and cooled over a period of tens of millions of years. There remains conflict, however, between metallographic cooling rate (Ni-metal) and radioisotopic thermochronometric data over the sizes and lifetimes of the chondrite parent bodies, as well as the timing of impact related disruptions. The importance of establishing the timing of parent body disruption is heightened by the use of meteorites as recorders of asteroid belt wide disruption events and their use to interpret Solar System dynamical models. Here we attempt to resolve these records by contributing new 207Pb-206Pb data obtained on phosphates isolated from nine previously unstudied ordinary chondrites. These new results, along with previously published Pb-phosphate, Ni-metal and thermometry data, are interpreted with a series of numerical models designed to simulate the thermal evolution for a chondrite parent body that either remains intact or is disrupted by impact prior to forming smaller unsorted "rubble piles". Our thermal model and previously published thermometry data limit accretion time to 2.05-2.25 Ma after CAIs. Measured Pb-phosphate data place minimum estimates on parent body diameters of ∼260-280 km for both the L and H chondrite parent bodies. They also consistently show that petrologic Type 6 (highest thermal metamorphism) chondrites from both the H and L bodies have younger ages and, therefore, cooled more slowly than Type 5 (lesser metamorphism) chondrites. This is interpreted as evidence for Type 5 chondrite origination from shallower depths than Type 6 chondrites within initially concentrically zoned bodies. This contrasts metallographic cooling rate data that are inconsistent with such a simple onion shell scenario. One

Cooling of a magmatic system under thermal chaotic mixing

NASA Astrophysics Data System (ADS)

Petrelli, Maurizio; El Omari, Kamal; Le Guer, Yves; Perugini, Diego

2015-04-01

The cooling of a melt undergoing chaotic advection is studied numerically for a magma with a temperature-dependent viscosity in a 2D cavity with moving boundary. Different statistical mixing and energy indicators are used to characterize the efficiency of cooling by thermal chaotic mixing. We show that different cooling rates can be obtained during the thermal mixing even of a single basaltic magmatic batch undergoing chaotic advection. This process can induce complex temperature patterns inside the magma chamber. The emergence of chaotic dynamics strongly affects the temperature field during time and greatly increases the cooling rates. This mechanism has implications for the lifetime of a magmatic body and may favor the appearance of chemical heterogeneities in igneous systems as a result of different crystallization rates. Results from this study also highlight that even a single magma batch can develop, under chaotic thermal advection, complex thermal and therefore compositional patterns resulting from different cooling rates, which can account for some natural features that, to date, have received unsatisfactory explanations. Among them, the production of magmatic enclaves showing completely different cooling histories compared with the host magma, compositional zoning in mineral phases, and the generation of large-scale compositionally zoning observed in many plutons worldwide.

Cooling of a Magmatic System Under Thermal Chaotic Mixing

NASA Astrophysics Data System (ADS)

El Omari, Kamal; Le Guer, Yves; Perugini, Diego; Petrelli, Maurizio

2015-07-01

The cooling of a basaltic melt undergoing chaotic advection is studied numerically for a magma with a temperature-dependent viscosity in a two-dimensional (2D) cavity with moving boundary. Different statistical mixing and energy indicators are used to characterize the efficiency of cooling by thermal chaotic mixing. We show that different cooling rates can be obtained during the thermal mixing of a single basaltic magmatic batch undergoing chaotic advection. This process can induce complex temperature patterns inside the magma chamber. The emergence of chaotic dynamics strongly modulates the temperature fields over time and greatly increases the cooling rates. This mechanism has implications for the thermal lifetime of the magmatic body and may favor the appearance of chemical heterogeneities in the igneous system as a result of different crystallization rates. Results from this study also highlight that even a single magma batch can develop, under chaotic thermal advection, complex thermal and therefore compositional patterns resulting from different cooling rates, which can account for some natural features that, to date, have received unsatisfactory explanations, including the production of magmatic enclaves showing completely different cooling histories compared with the host magma, compositional zoning in mineral phases, and the generation of large-scale compositional zoning observed in many plutons worldwide.

Early life history and spatiotemporal changes in distribution of the rediscovered Suwannee moccasinshell Medionidus walkeri (Bivalvia: Unionidae)

USGS Publications Warehouse

Johnson, Nathan A.; Mcleod, John; Holcomb, Jordan; Rowe, Matthew T.; Williams, James D.

2016-01-01

Accurate distribution data are critical to the development of conservation and management strategies for imperiled species, particularly for narrow endemics with life history traits that make them vulnerable to extinction. Medionidus walkeri is a rare freshwater mussel endemic to the Suwannee River Basin in southeastern North America. This species was rediscovered in 2012 after a 16-year hiatus between collections and is currently proposed for listing under the Endangered Species Act. Our study fills knowledge gaps regarding changes in distribution and early life history requirements of M. walkeri. Spatiotemporal changes in M. walkeri distribution were displayed using a conservation status assessment map incorporating metadata from 98 historical (1916–1999) and 401 recent (2000–2015) site surveys from museums and field notes representing records for 312 specimens. Recent surveys detected M. walkeri only in the middle Suwannee subbasin (n = 86, 22 locations) and lower Santa Fe subbasin (n = 2, 2 locations), and it appears the species may be extirpated from 67% of historically occupied 10-digit HUCs. In our laboratory experiments, M. walkeri successfully metamorphosed on Percina nigrofasciata (56.2% ± 8.9) and Etheostoma edwini (16.1% ± 7.9) but not on Trinectes maculatus, Lepomis marginatus, Notropis texanus, Noturus leptacanthus, Etheostoma fusiforme, or Gambusia holbrooki. We characterize M. walkeri as a lure-displaying host fish specialist and a long-term brooder (bradytictic), gravid from fall to early summer of the following year. The early life history and distribution data presented here provide the baseline framework for listing decisions and future efforts to conserve and recover the species.

Evidence for an agitated-aggressive syndrome in early-onset psychosis correlated with antisocial personality disorder, forensic history, and substance use disorder.

PubMed

Huber, Christian G; Hochstrasser, Lisa; Meister, Klara; Schimmelmann, Benno G; Lambert, Martin

2016-08-01

Agitation, aggression, and violence are increased in psychotic disorders. Additionally, an earlier age at onset may be associated with aggressive behavior. However, the relationship of age at onset, an agitated-aggressive syndrome as measured with the Positive And Negative Syndrome Scale for Schizophrenia - Excited Component (PANSS-EC), and its potential correlates in first-episode psychosis (FEP) has not been studied. This study assessed the association between age at onset, an agitated-aggressive syndrome, and its potential correlates in a prospective sample of 52 FEP patients with early-onset and adult-onset followed up for 12months. Twenty-six patients conformed to the criteria of early-onset psychosis. Early age at onset was associated with antisocial personality disorder (p=0.004; φc=0.39), a history of legal involvement (p=0.005; φc=0.39), and higher rates of lifetime substance use disorder (SUD; p=0.002; φc=0.42). Early-onset patients had significantly higher PANSS-EC scores over the course of observation (F(1,44.4)=5.39; p=0.025; d=0.656), but no significant group differences emerged for the remaining PANSS subscores. PANSS-EC scores were correlated positively with antisocial personality disorder and forensic history at 6weeks, 3months, 6months, and 12months, and with lifetime substance use disorder at 3months and 6months. Patients with early onset psychosis may have increased levels of agitation/aggressiveness, and, more likely, antisocial personality disorder, forensic history, and lifetime substance use disorder. These variables were linked to suicidality, aggressiveness, and involuntary treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

Crustal formation and recycling in an oceanic environment in the early Earth

NASA Astrophysics Data System (ADS)

van Thienen, P.; van den Berg, A. P.; Vlaar, N. J.

2003-04-01

Several lines of evidence indicate higher mantle temperatures (by some hundreds of degrees) during the early history of the Earth. Due to the strong effect of temperature on viscosity as well as on the degree of melting, this enforces a geodynamic regime which is different from the present plate tectonics, and in which smaller scale processes play a more important role. Upwelling of a hotter mantle produces a thicker oceanic crust, of which the lower part may reside in the eclogite stability field. This facilitates delamination, making room for fresh mantle material which may partly melt and add new material to the crust (Vlaar et al., 1994). We present results of numerical thermo-chemical convection models including a simple approximate melt segregation mechanism in which we investigate this alternative geodynamic regime, and its effect on the cooling history and chemical evolution of the mantle. Our results show that the mechanism is capable of working on two scales. On a small scale, involving the lower boundary of the crust, delaminations and downward transport of eclogite into the upper mantle takes place. On a larger scale, involving the entire crustal column, (parts of) the crust may episodically sink into the mantle and be replaced by a fresh crust. Both are capable of significantly and rapidly cooling a hot upper mantle by driving partial melting and thus the generation of new crust. After some hundreds of millions of years, as the temperature drops, the mechanism shuts itself off, and the cooling rate significantly decreases. Vlaar, N.J., P.E. van Keken and A.P. van den Berg (1994), Cooling of the Earth in the Archaean: consequences of pressure-release melting in a hotter mantle, Earth and Planetary Science Letters, vol 121, pp. 1-18

Global cooling?

PubMed

Damon, P E; Kunen, S M

1976-08-06

The world's inhabitants, including Scientists, live primarily in the Northern Hemisphere. It is quite natural to be concerned about events that occur close to home and neglect faraway events. Hence, it is not surprising that so little attention has been given to the Southern Hemisphere. Evidence for global cooling has been based, in large part, on a severe cooling trend at high northern latitudes. This article points out that the Northern Hemisphere cooling trend appears to be out of phase with a warming trend at high latitudes in the Southern Hemisphere. The data are scanty. We cannot be sure that these temperature fluctuations are be not the result of natural causes. How it seems most likely that human activity has already significantly perturbed the atmospheric weather system. The effect of particulate matter pollution should be most severe in the highly populated and industrialized Northern Hemisphere. Because of the rapid diffusion of CO(2) molecules within the atmosphere, both hemispheres will be subject to warming due to the atmospheric (greenhouse) effect as the CO(2) content of the atmosphere builds up from the combustion of fossil fuels. Because of the differential effects of the two major sources of atmospheric pollution, the CO(2) greenhouse effect warming trend should first become evident in the Southern Hemisphere. The socioeconomic and political consequences of climate change are profound. We need an early warning system such as would be provided by a more intensive international world weather watch, particularly at high northern and southern latitudes.

Effect of core cooling on the radius of sub-Neptune planets

NASA Astrophysics Data System (ADS)

Vazan, A.; Ormel, C. W.; Dominik, C.

2018-02-01

Sub-Neptune planets are very common in our Galaxy and show a large diversity in their mass-radius relation. In sub-Neptunes most of the planet mass is in the rocky part (hereafter, core), which is surrounded by a modest hydrogen-helium envelope. As a result, the total initial heat content of such a planet is dominated by that of the core. Nonetheless, most studies contend that the core cooling only has a minor effect on the radius evolution of the gaseous envelope because the cooling of the core is in sync with the envelope; that is most of the initial heat is released early on timescales of 10-100 Myr. In this Letter we examined the importance of the core cooling rate for the thermal evolution of the envelope. Thus, we relaxed the early core cooling assumption and present a model in which the core is characterized by two parameters: the initial temperature and the cooling time. We find that core cooling can significantly enhance the radius of the planet when it operates on a timescale similar to the observed age, i.e. Gyr. Consequently, the interpretation of the mass-radius observations of sub-Neptunes depends on the assumed core thermal properties and the uncertainty therein. The degeneracy of composition and core thermal properties can be reduced by obtaining better estimates of the planet ages (in addition to their radii and masses) as envisioned by future observations.

Influencing factors for early acute cerebrovascular accidents in patients with stroke history following off-pump coronary artery bypass grafting.

PubMed

Wang, Bin; Jia, Ming; Jia, Shijie; Wan, Jiuhe; Zhou, Xiao; Luo, Zhimin; Zhou, Ye; Zhang, Jianqun

2014-06-01

To analyse risk factors for early acute cerebrovascular accidents following off-pump coronary artery bypass grafting (OPCAB) in patients with stroke history, and to propose preventive measures to reduce the incidence of these events. A total of 468 patients with a history of stroke underwent OPCAB surgery in Beijing Anzhen Hospital of China from January 2010 to September 2012. They were retrospectively divided into two groups according to the occurrence of early acute cerebrovascular accidents within 48 hours following OPCAB. Multivariate logistic regression analysis was used to find risk or protective factors for early acute cerebrovascular accidents following the OPCAB. Fifty-two patients (11.1%) suffered from early acute cerebrovascular accidents in 468 patients, including 39 cases of cerebral infarction, two cases of cerebral haemorrhage, 11 cases of transient ischaemic attack (TIA). There were significant differences between the two groups in preoperative left ventricular ejection fraction ≤ 35%, severe bilateral carotid artery stenosis, poorly controlled hypertension, intraoperative application of Enclose® II proximal anastomotic device, postoperative acute myocardial infarction, atrial fibrillation, hypotension, ventilation time > 48h, ICU duration >48h and mortality. Multivariate logistic regression analysis showed that preoperative severe bilateral carotid stenosis (OR=6.378, 95%CI: 2.278-20.987) and preoperative left ventricular ejection fraction ≤ 35% (OR=2.737, 95%CI: 1.267-6.389), postoperative acute myocardial infarction (OR=3.644, 95%CI: 1.928-6.876), postoperative atrial fibrillation (OR=3.104, 95%CI:1.135∼8.016) and postoperative hypotension (OR=4.173, 95%CI: 1.836∼9.701) were independent risk factors for early acute cerebrovascular accidents in patients with a history of stroke following OPCAB procedures, while intraoperative application of Enclose® II proximal anastomotic device was protective factor (OR=0.556, 95%CI: 0.337-0.925). This

Class Climate Moderates Peer Relations and Emotional Adjustment in Children with an Early History of Anxious Solitude: A Child x Environment Model

ERIC Educational Resources Information Center

Gazelle, Heidi

2006-01-01

Classroom emotional climate was hypothesized to moderate psychosocial adjustment in 1st grade for children with an early childhood history of anxious solitude. Participants were 1,364 children in the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and their mothers, child-care providers, and teachers.…

Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias

NASA Astrophysics Data System (ADS)

Medezinski, Elinor; Battaglia, Nicholas; Coupon, Jean; Cen, Renyue; Gaspari, Massimo; Strauss, Michael A.; Spergel, David N.

2017-02-01

There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (I.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determining their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine the origin of the bimodality.

Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medezinski, Elinor; Battaglia, Nicholas; Cen, Renyue

2017-02-10

There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (i.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determiningmore » their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6 σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine the origin of the bimodality.« less

The Early History of Life

NASA Astrophysics Data System (ADS)

Nisbet, E. G.; Fowler, C. M. R.

2003-12-01

ago, for the most part the planet was peaceful. Even the most active volcanoes are mostly quiet; meteorites large enough to extinguish all dinosaurs may have hit as often as every few thousand years, but this is not enough to be a nuisance to a bacterium (except when the impact boiled the ocean); while to the photosynthesizer long-term shifts in the solar spectrum may be less of a problem than cloudy hazy days. Though, admittedly, green is junk light to biology, the excretion from the photosynthetic antennae, nevertheless even a green sky would have had other wavelengths also in its spectrum.Most important of all, like all good houses, this planet had location: Earth was just in the right spot. Not too far from the faint young Sun (Sagan and Chyba, 1997), it was also far enough away still to be in the comfort zone ( Kasting et al., 1993) when the mature Sun brightened. As many have pointed out, when Goldilocks arrived, she found everything just right. But what is less obvious is that as she grew and changed, and the room changed too, she commenced to rearrange the furniture to make it ever righter for her. Thus far, the bears have not arrived, though they may have reclaimed Mars from Goldilocks's sister see ( Figure 1). (3K)Figure 1. The habitable zone (Kasting et al., 1993). Too close to the Sun, a planet's surface is too hot to be habitable; too far, it is too cold. Early in the history of the solar system, the Sun was faint and the habitable zone was relatively close; 4.5 Ga later, with a brighter Sun, planets formerly habitable are now too hot, and the habitable zone has shifted out. Note that boundaries can shift. By changing its albedo and by altering the greenhouse gas content of the air, the planet can significantly widen the bounds of the habitable zone (Lovelock, 1979, 1988).

Diagenetic history of late Oligocene-early Miocene carbonates in East Sabah, Malaysia

NASA Astrophysics Data System (ADS)

Zainal Abidin, N. S.; Raymond, R. R.; Bashah, N. S. I.

2017-10-01

Limestones are particularly susceptible to drastic early diagenesis modifications, mainly cementation and dissolution. During the early Miocene, a major tectonic deformation has caused a widespread of uplift in Sabah. This has resulted change in depositional environment from deep to shallow marine, which favours the deposition of Gomantong Limestone. This study aims to investigate the diagenetic history of Gomantong Limestone in East Sabah. Thorough understanding of the diagenetic processes may provide data to unravel the tectonic activities which affected the reservoir quality of the carbonates. Combining the data from comprehensive petrographic analysis, and Scanning Electron Microscopy (SEM) of 30 samples, two main cements type were identified. These are microcrystalline cement and Mg-calcite cement of granular and blocky mosaics which are dominantly seen in all samples. The sequence of diagenesis events are determined as (1) micritization; (2) grain scale compaction; (3) cementation (pore-filling); (4) mechanical compaction and cementation infilling fractures and (5) chemical compaction. These diagenetic events are interpreted as reflection of changes in diagenetic environment from shallow marine to deep burial. The massive cementation in the Gomantong Limestone has resulted into a poor reservoir quality.

Alkenone-based reconstructions show four-phase Holocene temperature history for Arctic Svalbard

NASA Astrophysics Data System (ADS)

van der Bilt, W. G. M.; D'Andrea, W. J.; Bakke, J.; Balascio, N.; Werner, J.; Bradley, R. S.

2016-12-01

Situated at the crossroads of global oceanic and atmospheric circulation patterns, the Arctic is a key component of Earth`s climate system. Amplified by sea-ice feedbacks, even modest shifts in regional heat budget drive large climate responses. This is highlighted by the dramatic response of the Arctic to global warming. Assessing the signature of underlying forcings require paleoclimate records, allowing us to expand our knowledge beyond the short instrumental period and contextualize ongoing warming. However, such data are scarce and sparse in the Arctic, limiting our ability to address these issues. We present two quantitative Holocene-length summer temperature reconstructions from the Arctic Svalbard archipelago. Temperature estimates are based on alkenone unsaturation ratios measured on sediment cores from two lakes. Our data reveal a dynamic Holocene temperature history, with reconstructed lake water temperatures spanning a range of 6-8 °C, and characterized by four phases. The Early Holocene was marked by an early ( 10.5 ka cal. BP) onset of insolation-driven Hypsithermal conditions, likely compounded by strengthening oceanic heat transport. This warm interval was interrupted by cooling between 10.5-8.3 ka cal. BP that we attribute to cooling effects from the melting Northern Hemisphere ice sheets. Temperatures declined throughout the Middle Holocene, following a gradual trend that was accentuated by two cooling steps between 7.8-7 ka cal. BP and 4.4-3.5 ka cal. BP. These transitions coincide with a strengthening influence of Arctic water and sea-ice in the adjacent eastern Fram Strait. During the Late Holocene (past 4 ka), temperature change decoupled from the still-declining insolation, and fluctuated around cold mean conditions. This study improves our understanding of Arctic climate dynamics by demonstrating that Holocene Svalbard temperatures were governed by an alternation of forcing mechanism.

On the non-existence of a sharp cooling break in gamma-ray burst afterglow spectra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uhm, Z. Lucas; Zhang, Bing, E-mail: uhm@physics.unlv.edu, E-mail: zhang@physics.unlv.edu

Although the widely used analytical afterglow model of gamma-ray bursts (GRBs) predicts a sharp cooling break ν {sub c} in its afterglow spectrum, the GRB observations so far rarely show clear evidence for a cooling break in their spectra or a corresponding temporal break in their light curves. Employing a Lagrangian description of the blast wave, we conduct a sophisticated calculation of the afterglow emission. We precisely follow the cooling history of non-thermal electrons accelerated into each Lagrangian shell. We show that a detailed calculation of afterglow spectra does not in fact give rise to a sharp cooling break atmore » ν {sub c}. Instead, it displays a very mild and smooth transition, which occurs gradually over a few orders of magnitude in energy or frequency. The main source of this slow transition is that different mini shells have different evolutionary histories of the comoving magnetic field strength B, so that deriving the current value of ν {sub c} of each mini shell requires an integration of its cooling rate over the time elapsed since its creation. We present the time evolution of optical and X-ray spectral indices to demonstrate the slow transition of spectral regimes and discuss the implications of our result in interpreting GRB afterglow data.« less

A history of early life parental loss or separation is associated with successful cognitive-behavioral therapy in major depressive disorder.

PubMed

Niciu, Mark J; Abdallah, Chadi G; Fenton, Lisa R; Fasula, Madonna K; Black, Anne; Anderson, George M; Sanacora, Gerard

2015-11-15

There is a clinical need for evidence-based psychotherapy response biomarkers in major depressive disorder (MDD). Based on previous studies, we hypothesized that lower 24-h urinary cortisol levels and a history of early life stress/trauma would predict an improved antidepressant response to cognitive-behavioral therapy (CBT). 50 currently depressed MDD subjects were enrolled. 24-h urine was collected and measured for cortisol levels by radioimmunoassay (RIA). Subjects were also administered early life stress/trauma measures at baseline: Global Perceived Early-Life Stress (GPELS), The Early Life Trauma Inventory (ELTI) and Klein Loss Scale (KLS). The efficacy of a twelve-week course of once-weekly CBT was evaluated by the primary outcome measure, the 24-item Hamilton Depression Rating Scale (HDRS24), at baseline and every four weeks, and the Beck Depression Inventory at baseline and weekly thereafter. 42 subjects had at least one complete follow-up visit (≥4 weeks of CBT), and 30 subjects completed the full 12-week course. Baseline 24-h urinary cortisol levels did not correlate with CBT's antidepressant response. Higher KLS scores, a measure of early life parental loss or separation, correlated with delta HDRS24 (rs=-0.39, padjusted=0.05). Complementary general linear model analysis revealed enhanced CBT efficacy in patients with a history of early life parental loss or separation [F(1,35)=6.65, p=0.01]. Small sample size, Treatment-naïve population. Early life parental separation or loss positively correlated with CBT's antidepressant efficacy in our sample and may warrant further study in larger clinical samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Microbial analysis of meatballs cooled with vacuum and conventional cooling.

PubMed

Ozturk, Hande Mutlu; Ozturk, Harun Kemal; Koçar, Gunnur

2017-08-01

Vacuum cooling is a rapid evaporative cooling technique and can be used for pre-cooling of leafy vegetables, mushroom, bakery, fishery, sauces, cooked food, meat and particulate foods. The aim of this study was to apply the vacuum cooling and the conventional cooling techniques for the cooling of the meatball and to show the vacuum pressure effect on the cooling time, the temperature decrease and microbial growth rate. The results of the vacuum cooling and the conventional cooling (cooling in the refrigerator) were compared with each other for different temperatures. The study shows that the conventional cooling was much slower than the vacuum cooling. Moreover, the microbial growth rate of the vacuum cooling was extremely low compared with the conventional cooling. Thus, the lowest microbial growth occurred at 0.7 kPa and the highest microbial growth was observed at 1.5 kPa for the vacuum cooling. The mass loss ratio for the conventional cooling and vacuum cooling was about 5 and 9% respectively.

Testing Numerical Models of Cool Core Galaxy Cluster Formation with X-Ray Observations

NASA Astrophysics Data System (ADS)

Henning, Jason W.; Gantner, Brennan; Burns, Jack O.; Hallman, Eric J.

2009-12-01

Using archival Chandra and ROSAT data along with numerical simulations, we compare the properties of cool core and non-cool core galaxy clusters, paying particular attention to the region beyond the cluster cores. With the use of single and double β-models, we demonstrate a statistically significant difference in the slopes of observed cluster surface brightness profiles while the cluster cores remain indistinguishable between the two cluster types. Additionally, through the use of hardness ratio profiles, we find evidence suggesting cool core clusters are cooler beyond their cores than non-cool core clusters of comparable mass and temperature, both in observed and simulated clusters. The similarities between real and simulated clusters supports a model presented in earlier work by the authors describing differing merger histories between cool core and non-cool core clusters. Discrepancies between real and simulated clusters will inform upcoming numerical models and simulations as to new ways to incorporate feedback in these systems.

Maternal dental history and child’s birth outcome and early cognitive development

PubMed Central

Daniels, JL; Rowland, AS; Longnecker, MP; Crawford, P; Golding, J

2013-01-01

Summary Prenatal exposure to high levels of mercury, radiation, and inflammation have been associated with adverse reproductive outcomes such as increases in preterm delivery, low birthweight, and delayed neurodevelopment. Few data are available to evaluate the potential effects of prenatal low-level exposure to these factors as might occur during dental care. We evaluated maternal dental history prior to and during pregnancy in relation to birth outcomes and early communicative development among offspring in a large cohort (n=7375) of British children born in 1991–1992. Dental history was assessed by questionnaire. The child’s communicative development was assessed using the MacArthur Communicative Development Inventory at 15 months of age. Total mercury was measured in umbilical cord tissue for a subset of the children. Overall, dental care, including amalgam fillings, was not associated with birth outcomes or language development. Having x-rays taken during pregnancy was not associated with birthweight measured continuously (β=14.7, p=0.4), but was associated with slightly increased odds of having a term, low birthweight baby (OR 1.9, 95%CI 1.0–3.4). More detailed evaluation of the potential adverse effects of elective dental treatment during pregnancy, particularly dental x-rays, may be warranted. PMID:17697075

Rate dependency and role of nitric oxide in the vascular response to direct cooling in human skin.

PubMed

Yamazaki, Fumio; Sone, Ryoko; Zhao, Kun; Alvarez, Guy E; Kosiba, Wojciech A; Johnson, John M

2006-01-01

Local cooling of nonglabrous skin without functional sympathetic nerves causes an initial vasodilation followed by vasoconstriction. To further characterize these responses to local cooling, we examined the importance of the rate of local cooling and the effect of nitric oxide synthase (NOS) inhibition in intact skin and in skin with vasoconstrictor function inhibited. Release of norepinephrine was blocked locally (iontophoresis) with bretylium tosylate (BT). Skin blood flow was monitored from the forearm by laser-Doppler flowmetry (LDF). Cutaneous vascular conductance (CVC) was calculated as the ratio of LDF to blood pressure. Local temperature was controlled over 6.3 cm2 around the sites of LDF measurement. Local cooling was applied at -0.33 or -4 degrees C/min. At -4 degrees C/min, CVC increased (P < 0.05) at BT sites in the early phase. At -0.33 degrees C/min, there was no early vasodilator response, but there was a delay in the onset of vasoconstriction relative to intact skin. The NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) (intradermal microdialysis) decreased (P < 0.05) CVC by 28.3 +/- 3.8% at untreated sites and by 46.9 +/- 6.3% at BT-treated sites from the value before infusion. Rapid local cooling (-4 degrees C/min) to 24 degrees C decreased (P < 0.05) CVC at both untreated (saline) sites and L-NAME only sites from the precooling levels, but it transiently increased (P < 0.05) CVC at both BT + saline sites and BT + L-NAME sites in the early phase. After 35-45 min of local cooling, CVC decreased at BT + saline sites relative to the precooling levels (P < 0.05), but at BT + L-NAME sites CVC was not reduced below the precooling level (P = 0.29). These findings suggest that the rate of local cooling, but not functional NOS, is an important determinant of the early non-adrenergic vasodilator response to local cooling and that functional NOS, adrenergic nerves, as well as other mechanisms play roles in vasoconstriction during prolonged local

Early Earth slab stagnation

NASA Astrophysics Data System (ADS)

Agrusta, R.; Van Hunen, J.

2016-12-01

At present day, the Earth's mantle exhibits a combination of stagnant and penetrating slabs within the transition zone, indicating a intermittent convection mode between layered and whole-mantle convection. Isoviscous thermal convection calculations show that in a hotter Earth, the natural mode of convection was dominated by double-layered convection, which may imply that slabs were more prone to stagnate in the transition zone. Today, slab penetration is to a large extent controlled by trench mobility for a plausible range of lower mantle viscosity and Clapeyron slope of the mantle phase transitions. Trench mobility is, in turn, governed by slab strength and density and upper plate forcing. In this study, we systematically investigate the slab-transition zone internation in the Early Earth, using 2D self-consistent numerical subduction models. Early Earth's higher mantle temperature facilitates decoupling between the plates and the underlying asthenosphere, and may result in slab sinking almost without trench retreat. Such behaviour together with a low resistance of a weak lower mantle may allow slabs to penetrate. The ability of slab to sink into the lower mantle throughout Earth's history may have important implications for Earth's evolution: it would provide efficient mass and heat flux through the transition zone therefore provide an efficient way to cool and mix the Earth's mantle.

Early Lactation and Infant Feeding Practices Differ by Maternal Gestational Diabetes History.

PubMed

Oza-Frank, Reena; Moreland, Jennifer J; McNamara, Kelly; Geraghty, Sheela R; Keim, Sarah A

2016-11-01

Detailed data on lactation practices by gestational diabetes mellitus (GDM) history are lacking, precluding potential explanations and targets for interventions to improve lactation intensity and duration and, ultimately, long-term maternal and child health. This study aimed to examine breastfeeding practices through 12 months postpartum by GDM history. Women who delivered a singleton, liveborn infant at The Ohio State University Wexner Medical Center (Columbus, OH), in 2011 completed a postal questionnaire to assess lactation and infant feeding practices and difficulties. Bivariate and multivariate associations between GDM history and lactation and infant feeding practices were examined. The sample included 432 women (62% response rate), including 7.9% who had GDM during the index pregnancy. Women with GDM initiated breastfeeding (at-the-breast or pumping) as often as women without any diabetes but were more likely to report introduction of formula within the first 2 days of life (79.4% vs 53.8%, P < .01; adjusted odds ratio: 3.48; 95% confidence interval, 1.47-8.26). Women with GDM initiated pumping 4 days earlier than women without diabetes ( P < .05), which was confirmed in adjusted analyses. There was no difference in the proportion of women reporting breastfeeding difficulty (odds ratio: 2.08; 95% confidence interval, 0.78-5.52). However, there was a trend toward women with GDM reporting more formula feeding and less at-the-breast feeding as strategies to address difficulty compared with women without diabetes. Additional research is needed to understand why women with GDM engage in different early lactation and infant feeding practices, and how best to promote and sustain breastfeeding among these women.

Oxygenation history of the Neoproterozoic to early Phanerozoic and the rise of land plants

NASA Astrophysics Data System (ADS)

Wallace, Malcolm W.; Hood, Ashleigh vS.; Shuster, Alice; Greig, Alan; Planavsky, Noah J.; Reed, Christopher P.

2017-05-01

There has been extensive debate about the history of Earth's oxygenation and the role that land plant evolution played in shaping Earth's ocean-atmosphere system. Here we use the rare earth element patterns in marine carbonates to monitor the structure of the marine redox landscape through the rise and diversification of animals and early land plants. In particular, we use the relative abundance of cerium (Ceanom), the only redox-sensitive rare earth element, in well-preserved marine cements and other marine precipitates to track seawater oxygen levels. Our results indicate that there was only a moderate increase in oceanic oxygenation during the Ediacaran (average Cryogenian Ceanom = 1.1, average Ediacaran Ceanom = 0.62), followed by a decrease in oxygen levels during the early Cambrian (average Cryogenian Ceanom = 0.90), with significant ocean anoxia persisting through the early and mid Paleozoic (average Early Cambrian-Early Devonian Ceanom = 0.84). It was not until the Late Devonian that oxygenation levels are comparable to the modern (average of all post-middle Devonian Ceanom = 0.55). Therefore, this work confirms growing evidence that the oxygenation of the Earth was neither unidirectional nor a simple two-stage process. Further, we provide evidence that it was not until the Late Devonian, when large land plants and forests first evolved, that oxygen levels reached those comparable to the modern world. This is recorded with the first modern-like negative Ceanom (values <0.6) occurring at around 380 Ma (Frasnian). This suggests that land plants, rather than animals, are the 'engineers' responsible for the modern fully oxygenated Earth system.

Early Days of Superfluid ^3He: An Experimenter's View

NASA Astrophysics Data System (ADS)

Lee, David

2010-03-01

The formulation of the BCS theory led theorists to investigate possible non-S-wave pairing in liquid ^3He. Unfortunately as time went on, estimates for the pairing temperature became unattainably low. Nevertheless, the push to lower temperatures by experimentalists continued and was facilitated by the invention of the dilution refrigerator. Nuclear adiabatic demagnetization could then be used to cool liquid ^3He to ˜1 mK as demonstrated by Goodkind. An alternate approach, suggested by Pomeranchuk, involved adiabatic compression of liquid ^3He into the solid phase. Efforts to develop this technique at the Kapitza Institute, La Jolla and Cornell achieved success in demonstrating cooling of mixtures of liquid and solid ^3He to ˜ 1 mK following dilution refrigerator pre-cooling. Although there was great pessimism regarding the possible observation of pairing in liquid ^3He, the unsettled problem of magnetic ordering in solid ^3He beckoned. Ultimately two phase transition along the melting curve were observed by Osheroff et al at Cornell. Although first associated with solid ^3He, extensive NMR studies showed them to be two new phases of liquid ^3He. A brief history of experiments at various laboratories following the discovery is given, along with early interpretations given by Anderson and Morel and Balian and Werthamer. The key role of Leggett's spin dynamics is also discussed.

Mapping Early American History: Beyond What Happened Where

ERIC Educational Resources Information Center

Milson, Andrew J.

2014-01-01

American history demands to be mapped. The stories of exploration, the colonies, the Louisiana Purchase, and so on are incomplete without maps to locate historical places, events, and conflicts. Yet maps can do more for the history teacher than simply illustrating what happened where or what territory was acquired when. Maps also provide clues…

An Hour in History

NASA Image and Video Library

2011-03-22

John C. Stennis Space Center historian Marco Giardino speaks to center employees during the first An Hour in History session March 22. The Stennis History Office launched the series as part of the rocket engine test facility's yearlong 50th anniversary celebration. The inaugural session focused on Stennis history during the early 1960s. Subsequent sessions will focus on other aspects of Stennis history as part of the '50 Years of Powering Dreams' anniversary theme.

Cooling, exhumation, and deformation in the Hindu Kush, NW Pakistan: New constraints from preliminary 40Ar/39Ar and fission track analyses

NASA Astrophysics Data System (ADS)

Faisal, Shah; Larson, Kyle P.; Camacho, Alfredo; Coutand, Isabelle

2018-06-01

Asian crust in the Hindu Kush region in northern Pakistan records a protracted history of rifting, subduction and collision not commonly preserved within the Himalaya. Because of this, it is key to understanding the development of the southern Eurasian margin both prior to and after collision with India. New mica 40Ar/39Ar and apatite fission track geochronologic data from this region provide constraints on the kinematics of the Hindu Kush. 40Ar/39Ar muscovite and biotite ages from the late Cambrian Kafiristan pluton are 379.7 ± 1.7 Ma and 47.2 ± 0.3 Ma, respectively. The muscovite age may record cooling or partial resetting, while the biotite age is interpreted to record a thermal disruption associated with the early stages of continental collision in the Himalayan system. A 111.0 ± 0.6 Ma muscovite age from the northern part of the Tirich Mir pluton (∼123 Ma old; U-Pb) is interpreted to indicate a recrystallization event ∼12 Myrs after its intrusion. In addition, a younger muscovite age of 47.5 ± 0.2 Ma was derived from the opposite side of the same pluton in the immediate hanging wall of the Tirich Mir fault. This Eocene age is interpreted to represent the time of recrystallization during fault (re)activation in the early stages of India-Asia continent-continent collision. 40Ar/39Ar biotite analysis from the Buni-Zom pluton yields an age of 61.6 ± 1.1 Ma and is interpreted to reflect cooling at mid-upper crustal levels subsequent to the pluton's emplacement in the middle Cretaceous. Finally, 17.1-21.3 Ma 40Ar/39Ar ages from the Garam Chasma pluton and surrounding metapelites indicate cooling immediately following crystallization of the leucogranite body in the earliest Miocene/latest Oligocene. The younger cooling history is resolved by fission track dating of apatite (AFT). In the vicinity of the bounding Tirich Mir fault, the Tirich Mir pluton yields an AFT age of 1.4 ± 0.3 Ma, which is consistent with active exhumation associated with the surface

European dry cooling tower operating experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeSteese, J.G.; Simhan, K.

1976-03-01

Interviews were held with representatives of major plants and equipment manufacturers to obtain current information on operating experience with dry cooling towers in Europe. The report documents the objectives, background, and organizational details of the study, and presents an itemized account of contacts made to obtain information. Plant selection was based on a merit index involving thermal capacity and length of service. A questionnaire was used to organize operational data, when available, into nine major categories of experience. Information was also solicited concerning the use of codes and standards to ensure the achievement of cooling tower performance. Several plant operatorsmore » provided finned-tube samples for metallographic analysis. Additionally, information on both operating experience and developing technology was supplied by European technical societies and research establishments. Information obtained from these contacts provides an updated and representative sample of European experience with dry cooling towers, which supplements some of the detailed reviews already available in the literature. In addition, the study presents categorized operating experience with installations which have not been reviewed so extensively, but nevertheless, have significant operational histories when ranked by the merit index. The contacts and interviews reported in the survey occurred between late March and October 1975. The study was motivated by the expressed interest of U.S. utility industry representatives who expect European experience to provide a basis of confidence that dry cooling is a reliable technology, applicable when necessary, to U.S. operating requirements.« less

Bichordites from the early Eocene of Cuba: significance in the evolutionary history of the spatangoids

NASA Astrophysics Data System (ADS)

Villegas-Martín, Jorge; Netto, Renata Guimarães

2017-12-01

The trace fossil Bichordites monastiriensis is found in early Eocene turbiditic sandstones of the upper-slope deposits from the Capdevila Formation in Los Palacios Basin, Pinar del Río region, western Cuba. The potential tracemakers of B. monastiriensis include fossil spatangoids from the family Eupatagidae. The record of Bichordites in the deposits from Cuba allows to suppose that Eupatagidae echinoids were the oldest potential tracemakers of Bichordites isp. and reinforce the hypothesis that the ichnological record are relevant in envisaging the evolutionary history of the spatangoids.

Classification of extremely metal-poor stars: absent region in A(C)-[Fe/H] plane and the role of dust cooling

NASA Astrophysics Data System (ADS)

Chiaki, Gen; Tominaga, Nozomu; Nozawa, Takaya

2017-11-01

Extremely metal-poor (EMP) stars are the living fossils with records of chemical enrichment history at the early epoch of galaxy formation. By the recent large observation campaigns, statistical samples of EMP stars have been obtained. This motivates us to reconsider their classification and formation conditions. From the observed lower limits of carbon and iron abundances of Acr(C) ∼ 6 and [Fe/H]cr ∼ -5 for C-enhanced EMP (CE-EMP) and C-normal EMP (CN-EMP) stars, we confirm that gas cooling by dust thermal emission is indispensable for the fragmentation of their parent clouds to form such low mass, i.e. long-lived stars, and that the dominant grain species are carbon and silicate, respectively. We constrain the grain radius r_i^cool of a species i and condensation efficiency fij of a key element j as r_C^cool / f_C,C = 10 {μ m} and r_Sil^cool / f_Sil,Mg = 0.1 {μ m} to reproduce Acr(C) and [Fe/H]cr, which give a universal condition 10[C/H] - 2.30 + 10[Fe/H] > 10-5.07 for the formation of every EMP star. Instead of the conventional boundary [C/Fe] = 0.7 between CE-EMP and CN-EMP stars, this condition suggests a physically meaningful boundary [C/Fe]b = 2.30 above and below which carbon and silicate grains are dominant coolants, respectively.

Characterizing the early life history of an imperiled freshwater mussel (Ptychobranchus jonesi) with host-fish determination and fecundity estimation

USGS Publications Warehouse

Mcleod, John; Jelks, Howard L.; Pursifull, Sandra; Johnson, Nathan A.

2017-01-01

Conservation of imperiled species is frequently challenged by insufficient knowledge of life history and environmental factors that affect various life stages. The larvae (glochidia) of most freshwater mussels in the family Unionidae are obligate ectoparasites of fishes. We described the early life history of the federally endangered Southern Kidneyshell Ptychobranchus jonesi and compared methods for estimating fecundity and conducting host trials on this conglutinate-producing mussel species. Glochidial inoculation baths and direct feeding of conglutinates to Percina nigrofasciata, Etheostoma edwini, and Etheostoma fusiforme resulted in successful metamorphosis to the juvenile life stage. Ptychobranchus jonesi glochidia did not metamorphose on 25 other species of fishes tested representing 11 families. Three juveniles were recovered from Gambusia holbrooki resulting in a metamorphosis rate <1%. We characterize P. jonesi as a host-fish specialist that fractionally releases conglutinates from late January to early June. Intact P. jonesi conglutinates resemble simuliid fly larvae attached to an egg-like structure, but most conglutinates were released as segments representing separate egg or larva mimics. Viability of glochidia encased within a conglutinate was >90% for ≥5 d. Feeding conglutinates directly to fishes allowed us to estimate seminatural infestation rates and calculate average numbers of juveniles produced per conglutinate, unlike the traditional approach of infesting fish hosts in an inoculation bath. Regressions based on the physical dimensions of each conglutinate or conglutinate segment were the most practical method used to estimate fecundity. Species distribution information, early life-history description, and methods developed for determining fecundity and conducting host trials may assist in the conservation of P. jonesi during recovery options that include captive propagation, augmentation, and reestablishment.

NASA Marshall Space Flight Center Improves Cooling System Performance: Best Management Practice Case Study #10: Cooling Towers (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) has a longstanding sustainability program that revolves around energy and water efficiency as well as environmental protection. MSFC identified a problematic cooling loop with six separate compressor heat exchangers and a history of poor efficiency. The facility engineering team at MSFC partnered with Flozone Services, Incorporated to implement a comprehensive water treatment platform to improve the overall efficiency of the system.

Exhumation history of the western Kyrgyz Tien Shan: Implications for intramontane basin formation

NASA Astrophysics Data System (ADS)

Bande, Alejandro; Sobel, Edward R.; Mikolaichuk, Alexander; Schmidt, Alexander; Stockli, Daniel F.

2017-01-01

The dextral Talas-Fergana Fault separates the western from the central Tien Shan. Recent work has shed light on the Cenozoic evolution of the eastern and central Tien Shan; much less attention has been paid to the western Tien Shan. In this contribution we present new thermochronological ages for the Fergana and Alai ranges that, combined with the available data set, constrain the Cenozoic exhumation history of the western Tien Shan. Following a tectonically quiet early Cenozoic period, we suggest an onset of exhumation at 25 Ma. This early onset was followed by a period of slower exhumation and in some areas minor reheating. A final, strong late Miocene rapid cooling event is well represented in the western Tien Shan as in other sectors of the range. The early onset of uplift of the western Tien Shan dissected the previously continuous westernmost Parathethyan Sea, progressively isolating basins (e.g., Fergana, Tarim, and Alai basins) in the central Asian hinterland. Moreover, the coeval timing of late Miocene uplift along the length of entire Tien Shan implies that neither the Pamir nor Tarim can be the sole driver for exhumation of the entire range.

[An early history of Japanese amyotrophic lateral sclerosis (ALS)-related diseases and the current development].

PubMed

Abe, Koji

2018-03-28

The present review focuses an early history of Japanese amyotrophic lateral sclerosis (ALS)-related diseases and the current development. In relation to foreign previous reports, five topics are introduced and discussed on ALS with dementia, ALS/Parkinsonism dementia complex (ALS/PDC), familial ALS (FALS), spinal bulbar muscular atrophy (SBMA), and multisystem involvement especially in cerebellar system of ALS including ALS/SCA (spinocerebellar ataxia) crossroad mutation Asidan. This review found the great contribution of Japanese reports on the above five topics, and confirmed the great development of ALS-related diseases over the past 120 years.

Comparing Social Stories™ to Cool versus Not Cool

ERIC Educational Resources Information Center

Leaf, Justin B.; Mitchell, Erin; Townley-Cochran, Donna; McEachin, John; Taubman, Mitchell; Leaf, Ronald

2016-01-01

In this study we compared the cool versus not cool procedure to Social Stories™ for teaching various social behaviors to one individual diagnosed with autism spectrum disorder. The researchers randomly assigned three social skills to the cool versus not cool procedure and three social skills to the Social Stories™ procedure. Naturalistic probes…

Impact History of the Moon

NASA Astrophysics Data System (ADS)

Cohen, B. A.; Bottke, W. F.; Norman, M. V.; van der Bogert, C. H.; Fassett, C. I.; Hiesinger, H.; Joy, K. H.; Mazrouei, S. A.; Nemchin, A.; Neumann, G. A.; Zellner, N. E. B.

2018-04-01

Establishing an absolute planetary chronology has important ramifications for understanding the early structure of the solar system and the geologic history of the planets. The Moon is the cornerstone for understanding this impact history.

The Application of Downdraught Cooling in Vernacular Skywell Dwellings in China

NASA Astrophysics Data System (ADS)

Xuan, H.; Lv, A. M.

2017-05-01

Traditional skywell dwellings in the hot climate regions of China represent an important cultural heritage. Achieving indoor comfort meeting occupants’ expectations, can contribute to the preservation of this unique traditional architecture. Improvement of ventilation and indoor temperatures through natural, sustainable and low impact solutions is an opportunity in achieving building thermal comfort in these traditional dwellings. The existence of skywells provides a good opportunity for the incorporation of downdraught cooling with minor interventions, and thus by avoiding extensive ductwork, saving energy and improving indoor temperatures, it can contribute to the preservation of traditional dwellings. Applicability of downdraught cooling, the history of traditional ventilation solutions, layout and space features of skywell dwelling are discussed and the way of incorporating downdraught cooling as an alternative to air-conditioning into these buildings is investigated.

Film cooling for a closed loop cooled airfoil

DOEpatents

Burdgick, Steven Sebastian; Yu, Yufeng Phillip; Itzel, Gary Michael

2003-01-01

Turbine stator vane segments have radially inner and outer walls with vanes extending therebetween. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upper surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. At least one film cooling hole is defined through a wall of at least one of the cavities for flow communication between an interior of the cavity and an exterior of the vane. The film cooling hole(s) are defined adjacent a potential low LCF life region, so that cooling medium that bleeds out through the film cooling hole(s) reduces a thermal gradient in a vicinity thereof, thereby the increase the LCF life of that region.

Liquid metal cooled nuclear reactors with passive cooling system

DOEpatents

Hunsbedt, Anstein; Fanning, Alan W.

1991-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of cooling medium flow circuits which cooperate to remove and carry heat away from the fuel core upon loss of the normal cooling flow circuit to areas external thereto.

The early history of the lunar inclination. [effect of tidal friction

NASA Technical Reports Server (NTRS)

Rubincam, D. P.

1973-01-01

The effect of tidal friction on the inclination of the lunar orbit to the earth's equator for earth-moon distances of less than 10 earth radii is examined. The results obtained bear on a conclusion drawn by Gerstenkorn and others which has been raised as a fatal objection to the fission hypothesis of lunar origin, namely, that the present nonzero inclination of the moon's orbit to the ecliptic implies a steep inclination of the moon's orbit to the earth's equatorial plane in the early history of the earth-moon system. This conclusion is shown to be valid only for particular rheological models of the earth. The earth is assumed to behave like a highly viscous fluid in response to tides raised in it by the moon. The moon is assumed to be tideless and in a circular orbit about the earth. The equations of tidal friction are integrated numerically to give inclination of the lunar orbit as a function of earth-moon distance.

Early diversification trend and Asian origin for extent bat lineages.

PubMed

Yu, W; Wu, Y; Yang, G

2014-10-01

Bats are a unique mammalian group, which belong to one of the largest and most diverse mammalian radiations, but their early diversification is still poorly understood, and conflicting hypotheses have emerged regarding their biogeographic history. Understanding their diversification is crucial for untangling the enigmatic evolutionary history of bats. In this study, we elucidated the rate of diversification and the biogeographic history of extant bat lineages using genus-level chronograms. The results suggest that a rapid adaptive radiation persisted from the emergence of crown bats until the Early Eocene Climatic Optimum, whereas there was a major deceleration in diversification around 35-49 Ma. There was a positive association between changes in the palaeotemperature and the net diversification rate until 35 Ma, which suggests that the palaeotemperature may have played an important role in the regulation of ecological opportunities. By contrast, there were unexpectedly higher diversification rates around 25-35 Ma during a period characterized by intense and long-lasting global cooling, which implies that intrinsic innovations or adaptations may have released some lineages from the intense selective pressures associated with these severe conditions. Our reconstruction of the ancestral distribution suggests an Asian origin for bats, thereby indicating that the current panglobal but disjunct distribution pattern of extant bats may be related to events involving seriate cross-continental dispersal and local extinction, as well as the influence of geological events and the expansion and contraction of megathermal rainforests during the Tertiary. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Cooling circuit for steam and air-cooled turbine nozzle stage

DOEpatents

Itzel, Gary Michael; Yu, Yufeng

2002-01-01

The turbine vane segment includes inner and outer walls with a vane extending therebetween. The vane includes leading and trailing edge cavities and intermediate cavities. An impingement plate is spaced from the outer wall to impingement-cool the outer wall. Post-impingement cooling air flows through holes in the outer wall to form a thin air-cooling film along the outer wall. Cooling air is supplied an insert sleeve with openings in the leading edge cavity for impingement-cooling the leading edge. Holes through the leading edge afford thin-film cooling about the leading edge. Cooling air is provided the trailing edge cavity and passes through holes in the side walls of the vane for thin-film cooling of the trailing edge. Steam flows through a pair of intermediate cavities for impingement-cooling of the side walls. Post-impingement steam flows to the inner wall for impingement-cooling of the inner wall and returns the post-impingement cooling steam through inserts in other intermediate cavities for impingement-cooling the side walls of the vane.

Making History Local: The Efficacy of Local History for Student Interest, Success, and Multicultural Awareness

ERIC Educational Resources Information Center

Paysinger, Christopher Browning

2012-01-01

This study was an action research design which examined the effects of infusing the local history of North Alabama into the traditional Early American History curriculum to assess the effect on student interest, multicultural awareness, and success on the Alabama High School Graduation Exam history portion. This study found no significance when…

Intracellular ice formation in mouse zygotes and early morulae vs. cooling rate and temperature-experimental vs. theory.

PubMed

Jin, Bo; Seki, Shinsuke; Paredes, Estefania; Qiu, Juan; Shi, Yanbin; Zhang, Zhenqiang; Ma, Chao; Jiang, Shuyan; Li, Jiaqi; Yuan, Feng; Wang, Shu; Shao, Xiaoguang; Mazur, Peter

2016-10-01

In this study, mature female mice of the ICR strain were induced to superovultate, mated, and collected at either zygote or early morula stages. Embryos suspended in 1 M ethylene glycol in PBS containing 10 mg/L Snomax for 15 min, then transferred in sample holder to Linkam cryostage, cooled to and seeded at 7 °C, and then observed and photographed while being cooled to -70 °C at 0.5-20 °C/min. Intracellular ice formation (IIF) was observed as abrupt ''flashing''. Two types of flashing or IIF were observed in this study. Extracellular freezing occurred at a mean of -7.7 °C. In morulae, about 25% turned dark within ±1 °C of extracellular ice formation (EIF). These we refer to as "high temperature'' flashers. In zygotes, there were no high temperature flashers. All the zygotes flashed at temperatures well below the temperature for EIF. Presumably high temperature flashers were a consequence of membrane damage prior to EIF or damage from EIF. We shall not discuss them further. In the majority of cases, IIF occurred well below -7.7 °C; these we call ''low temperature'' flashers. None flashed with cooling rate (CR) of 0.5 °C/min in either zygotes or morulae. Nearly all flashed with CR of 4 °C/min or higher, but the distribution of temperatures is much broader with morulae than with zygotes. Also, the mean flashing temperature is much higher with morulae (-20.9 °C) than with zygotes (-40.3 °C). We computed the kinetics of water loss with respect to CR and temperature in both mouse zygotes and in morulae based on published estimates of Lp and it is Ea. The resulting dehydration curves combined with knowledge of the embryo nucleation temperature permits an estimate of the likelihood of IIF as a function of CR and subzero temperature. The agreement between these computed probabilities and the observed values are good. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Parents' and Teachers' Views on the Psychosocial Adjustment of Students with and without a History of Early Grade Retention

ERIC Educational Resources Information Center

Anastasiou, Andri I.; Papachristou, Eleni M.; Diakidoy, Irene-Anna N.

2017-01-01

The study compared teachers' and parents' views about elementary school children's psychosocial adjustment with and without a history of early grade retention. The sample included retained and non-retained students currently in Grades Two and Four (age range 7.5 to 11.6 years) in Cypriot public schools. The retained students experienced early…

Early life history and survival of natural subyearling fall chinook salmon in the Snake and Clearwater rivers in 1995

USGS Publications Warehouse

Connor, William P.; Bjornn, Theodore C.; Burge, Howard L.; Garcia, Aaron P.; Rondorf, Dennis W.

1997-01-01

The objectives of this segment of our study were to (1) describe the early life history characteristics of naturally produced subyearling fall chinook salmon in the Snake and Clearwater rivers, and (2) estimate survival for juvenile fall chinook salmon emigrating from the Snake and Clearwater rivers to the tail race of Lower Granite Dam.

Thermal and impact history of the H chondrite parent asteroid during metamorphism: Constraints from metallic Fe-Ni

NASA Astrophysics Data System (ADS)

Scott, Edward R. D.; Krot, Tatiana V.; Goldstein, Joseph I.; Wakita, Shigeru

2014-07-01

We have studied cloudy taenite, metallographic cooling rates, and shock effects in 30 H3-6 chondrites to elucidate the thermal and early impact history of the H chondrite parent body. We focused on H chondrites with old Ar-Ar ages (>4.4 Gyr) and unshocked and mildly shocked H chondrites, as strongly shocked chondrites with such old ages are very rare. Cooling rates for most H chondrites at 500 °C are 10-50 °C/Myr and do not decrease systematically with increasing petrologic type as predicted by the onion-shell model in which types 3-5 are arranged in concentric layers around a type 6 core. Some type 4 chondrites cooled slower than some type 6 chondrites and type 3 chondrites did not cool faster than other types, contrary to the onion-shell model. Cloudy taenite particle sizes, which range from 40 to 120 nm, are inversely correlated with metallographic cooling rates and show that the latter were not compromised by shock heating. The three H4 chondrites that were used to develop the onion-shell model, Ste. Marguerite, Beaver Creek, and Forest Vale, cooled through 500 °C at ⩾5000 °C/Myr. Our thermal modeling shows that these rates are 50× higher than could be achieved in a body that was heated by 26Al and cooled without disturbance by impact. Published Ar-Ar ages do not decrease systematically with increasing petrologic type but do correlate inversely with cloudy taenite particle size suggesting that impact mixing decreased during metamorphism. Metal and silicate compositions in regolith breccias show that impacts mixed material after metamorphism without causing significant heating. Impacts during metamorphism created Portales Valley and two other H6 chondrites with large metallic veins, excavated the fast-cooled H4 chondrites around 3-4 Myr after accretion, and mixed petrologic types. Metallographic data do not require catastrophic disruption by impact during cooling.

Influences of spawning timing, water temperature, and climatic warming on early life history phenology in western Alaska sockeye salmon

USGS Publications Warehouse

Sparks, Morgan M.; Falke, Jeffrey A.; Quinn, Thomas P.; Adkison, Milo D.; Schindler, Daniel E.; Bartz, Krista K.; Young, Daniel B.; Westley, Peter A. H.

2018-01-01

We applied an empirical model to predict hatching and emergence timing for 25 western Alaska sockeye salmon (Oncorhynchus nerka) populations in four lake-nursery systems to explore current patterns and potential responses of early life history phenology to warming water temperatures. Given experienced temperature regimes during development, we predicted hatching to occur in as few as 58 d to as many as 260 d depending on spawning timing and temperature. For a focal lake spawning population, our climate-lake temperature model predicted a water temperature increase of 0.7 to 1.4 °C from 2015 to 2099 during the incubation period, which translated to a 16 d to 30 d earlier hatching timing. The most extreme scenarios of warming advanced development by approximately a week earlier than historical minima and thus climatic warming may lead to only modest shifts in phenology during the early life history stage of this population. The marked variation in the predicted timing of hatching and emergence among populations in close proximity on the landscape may serve to buffer this metapopulation from climate change.

Postexercise Cooling Rates in 2 Cooling Jackets

PubMed Central

Brade, Carly; Dawson, Brian; Wallman, Karen; Polglaze, Ted

2010-01-01

Abstract Context: Cooling jackets are a common method for removing stored heat accumulated during exercise. To date, the efficiency and practicality of different types of cooling jackets have received minimal investigation. Objective: To examine whether a cooling jacket containing a phase-change material (PC17) results in more rapid postexercise cooling than a gel cooling jacket and a no-jacket (control) condition. Design: Randomized, counterbalanced design with 3 experimental conditions. Setting: Participants exercised at 75% V̇o2max workload in a hot climate chamber (temperature  =  35.0 ± 1.4°C, relative humidity  =  52 ± 4%) for 30 minutes, followed by postexercise cooling for 30 minutes in cool laboratory conditions (ambient temperature  =  24.9 ± 1.8°C, relative humidity  =  39% ± 10%). Patients or Other Participants: Twelve physically active men (age  =  21.3 ± 1.1 years, height  =  182.7 ± 7.1 cm, body mass  =  76.2 ± 9.5 kg, sum of 6 skinfolds  =  50.5 ± 6.9 mm, body surface area  =  1.98 ± 0.14 m2, V̇o2max  =  49.0 ± 7.0 mL·kg−1·min−1) participated. Intervention(s): Three experimental conditions, consisting of a PC17 jacket, a gel jacket, and no jacket. Main Outcome Measure(s): Core temperature (TC), mean skin temperature (TSk), and TC cooling rate (°C/min). Results: Mean peak TC postexercise was 38.49 ± 0.42°C, 38.57 ± 0.41°C, and 38.55 ± 0.40°C for the PC17 jacket, gel jacket, and control conditions, respectively. No differences were observed in peak TC cooling rates among the PC17 jacket (0.038 ± 0.007°C/min), gel jacket (0.040 ± 0.009°C/min), and control (0.034 ± 0.010°C/min, P > .05) conditions. Between trials, no differences were calculated for mean TSk cooling. Conclusions: Similar cooling rates for all 3 conditions indicate that there is no benefit associated with wearing the PC17 or gel jacket. PMID:20210620

History + Mystery = Inquiring Young Historians

ERIC Educational Resources Information Center

Kirchner, Jana; Helm, Allison; Pierce, Kristin; Galloway, Michele

2011-01-01

While social studies content about communities, neighborhood jobs, and maybe even some state history is taught in the early elementary grades, often the upper elementary grades are the first time students learn about the larger progression of history. How do teachers begin to teach the progression of U.S. history and the themes and questions that…

Early Cenozoic "dome like" exhumation around the Irish Sea

NASA Astrophysics Data System (ADS)

Doepke, Daniel; Cogné, Nathan; Chew, David; Stuart, Fin

2016-04-01

Despite decades of research the Early Cenozoic exhumation history of Ireland and Britain is still poorly understood and subject to contentious debate (see Davis et al., 2012 and subsequent comments). Previous studies have attributed the Cenozoic exhumation history of Ireland and Britain mainly to: (a) Paleogene - Neogene far-field stress between the opening of the North Atlantic Ocean and the Alpine collision (Ziegler et al., 1995; Hillis et al., 2008) or (b) early Paleogene mantle driven magmatic underplating associated with the development of the proto-Iceland mantle plume beneath the Irish Sea (Brodie and White, 1994; Al-Kindi et al., 2003). The major differences between the two hypotheses are the pattern and timing of spatial exhumation. This project thus seeks to investigate the timing and mechanisms of late Mesozoic - early Cenozoic exhumation on the onshore part of the British Isles by using a combination of apatite fission track (AFT) and apatite (U-Th-Sm)/He (AHe) data, which we then model using the QTQt program of Gallagher (2012) to better constrain the modelled thermal histories. Our studied area centres on the margins of the Irish Sea, but includes all Ireland and western Britain. Overall we analysed 74 samples for AFT and 66 samples for AHe dating. In particular, our results include ten pseudo-vertical profiles. The AFT ages display a wide range of ages from early Carboniferous in Scotland to early Eocene in central Ireland. Our AHe ages range from mid Permian on Shetland to Eocene Ft-corrected. The AFT data do not show any specific spatial distribution, however, the Ft-corrected AHe ages around the Irish Sea only focus around late Cretaceous to Eocene suggesting an important thermal event around this time. The modelled thermal histories of samples located around the Irish Sea and western Scotland show a clear late Cretaceous to early Paleogene cooling event which is not present elsewhere. The distribution of this cooling event is broadly consistent

An integrated study on microtectonics, geothermometry and thermochronology of the Çataldaǧ Core Complex (NW Turkey): Implications for cooling, deformation and uplift history

NASA Astrophysics Data System (ADS)

Kamaci, Omer; Altunkaynak, Safak

2017-04-01

We present an integrated study on structure, microstructure, geothermometry and thermochronology of the Çataldaǧ Core Complex (ÇCC) in NW Turkey in order to understand the cooling, deformation and uplift mechanisms. ÇCC is formed from an Eo-Oligocene granite-gneiss-migmatite complex (GGMC) and an Early Miocene I-type granodioritic body (ÇG: Çataldaǧ granodiorite) which were exhumed as a dome-shaped core complex in the footwall of a ring-shaped low-angle detachment zone (The Çataldaǧ Detachment Fault Zone; ÇDFZ) in the Early Miocene. New U-Pb zircon (LA-ICPMS) and monazite ages of GGMC yielded magmatic ages of 33.8 and 30.1 Ma (Latest Eocene-Early Oligocene). 40Ar/39Ar muscovite, biotite and K-feldspar from the GGMC yielded the deformation age span 21.38±0,05 Ma and 20.81±0.04 Ma, which is also the emplacement age (20.84±0.13 Ma and 21.6±0.04 Ma) of ÇG. ÇDFZ is responsible for mainly top-to-the-north sense kinematic processes. The microstructural features of quartz, feldspar and mica indicate that the ÇCC has undergone continuous deformations during its cooling, from submagmatic to cataclastic conditions. Five microstructural grades have been classified under ductile (DZ) and ductile-to-brittle shear zone (SZ), according to the estimated deformation temperature and intensity of the strain. Microcline twinning, marginally replacement myrmekite and flame-perthite are predominant features for feldspar while chessboard extinction, grain boundary migration and subgrain rotation recrystallization is common for quartz in the DZ which has a deformation temperature range of >600°C to 400°C. Grain size reduction is an important factor for the ductile to brittle shear zone (SZ). Feldspar is represented by bulging recrystallization (BLG), feldspar-fish and domino-type microfracture/microfaulting and quartz show more elongated structures such as ribbons with high aspect ratios. Mineral-fish (muscovite, biotite and feldspar) structures indicate a temperature

An organismal concept for Sengelia radicans gen. et sp. nov. – morphology and natural history of an Early Devonian lycophyte

PubMed Central

Tomescu, Alexandru M. F.

2017-01-01

Abstract Background and Aims Fossil plants are found as fragmentary remains and understanding them as natural species requires assembly of whole-organism concepts that integrate different plant parts. Such concepts are essential for incorporating fossils in hypotheses of plant evolution and phylogeny. Plants of the Early Devonian are crucial to reconstructing the initial radiation of tracheophytes, yet few are understood as whole organisms. Methods This study assembles a whole-plant concept for the Early Devonian lycophyte Sengelia radicans gen. et sp. nov., based on morphometric data and taphonomic observations from >1000 specimens collected in the Beartooth Butte Formation (Wyoming, USA). Key Results Sengelia radicans occupies a key position between stem-group and derived lycophyte lineages. Sengelia had a rooting system of downward-growing root-bearing stems, formed dense monotypic mats of prostrate shoots in areas that experienced periodic flooding, and was characterized by a life-history strategy adapted for survival after floods, dominated by clonality, and featuring infrequent sexual reproduction. Conclusions Sengelia radicans is the oldest among the very few early tracheophytes for which a detailed, rigorous whole-plant concept integrates morphology, growth habit, life history and growth environment. This plant adds to the diversity of body plans documented among lycophytes and may help elucidate patterns of morphological evolution in the clade. PMID:28334100

AP American History and the History Major: Keeping Body and Soul Together.

ERIC Educational Resources Information Center

Holbo, Paul S.

For college-level American History, in the high school advanced placement (AP) program and on university campuses, these are the best of times and the worst of times. For the American History AP program, the early 1970's were difficult times, with the examinations under attack as elitist and irrelevant to contemporary problems. The program…

Quantum enhanced feedback cooling of a mechanical oscillator using nonclassical light.

PubMed

Schäfermeier, Clemens; Kerdoncuff, Hugo; Hoff, Ulrich B; Fu, Hao; Huck, Alexander; Bilek, Jan; Harris, Glen I; Bowen, Warwick P; Gehring, Tobias; Andersen, Ulrik L

2016-11-29

Laser cooling is a fundamental technique used in primary atomic frequency standards, quantum computers, quantum condensed matter physics and tests of fundamental physics, among other areas. It has been known since the early 1990s that laser cooling can, in principle, be improved by using squeezed light as an electromagnetic reservoir; while quantum feedback control using a squeezed light probe is also predicted to allow improved cooling. Here we show the implementation of quantum feedback control of a micro-mechanical oscillator using squeezed probe light. This allows quantum-enhanced feedback cooling with a measurement rate greater than it is possible with classical light, and a consequent reduction in the final oscillator temperature. Our results have significance for future applications in areas ranging from quantum information networks, to quantum-enhanced force and displacement measurements and fundamental tests of macroscopic quantum mechanics.

Preventing Early Child Maltreatment: Implications from a Longitudinal Study of Maternal Abuse History, Substance Use Problems, and Offspring Victimization

PubMed Central

Appleyard, Karen; Berlin, Lisa J.; Rosanbalm, Katherine D.; Dodge, Kenneth A.

2013-01-01

In the interest of improving child maltreatment prevention science, this longitudinal, community based study of 499 mothers and their infants tested the hypothesis that mothers’ childhood history of maltreatment would predict maternal substance use problems, which in turn would predict offspring victimization. Mothers (35% White/non-Latina, 34% Black/non-Latina, 23% Latina, 7% other) were recruited and interviewed during pregnancy, and child protective services records were reviewed for the presence of the participants’ target infants between birth and age 26 months. Mediating pathways were examined through structural equation modeling and tested using the products of the coefficients approach. The mediated pathway from maternal history of sexual abuse to substance use problems to offspring victimization was significant (standardized mediated path [ab]=.07, 95% CI [.02, .14]; effect size=.26), as was the mediated pathway from maternal history of physical abuse to substance use problems to offspring victimization (standardized mediated path [ab]=.05, 95% CI [.01, .11]; effect size =.19). There was no significant mediated pathway from maternal history of neglect. Findings are discussed in terms of specific implications for child maltreatment prevention, including the importance of assessment and early intervention for maternal history of maltreatment and substance use problems, targeting women with maltreatment histories for substance use services, and integrating child welfare and parenting programs with substance use treatment. PMID:21240556

Preventing early child maltreatment: implications from a longitudinal study of maternal abuse history, substance use problems, and offspring victimization.

PubMed

Appleyard, Karen; Berlin, Lisa J; Rosanbalm, Katherine D; Dodge, Kenneth A

2011-06-01

In the interest of improving child maltreatment prevention science, this longitudinal, community based study of 499 mothers and their infants tested the hypothesis that mothers' childhood history of maltreatment would predict maternal substance use problems, which in turn would predict offspring victimization. Mothers (35% White/non-Latina, 34% Black/non-Latina, 23% Latina, 7% other) were recruited and interviewed during pregnancy, and child protective services records were reviewed for the presence of the participants' target infants between birth and age 26 months. Mediating pathways were examined through structural equation modeling and tested using the products of the coefficients approach. The mediated pathway from maternal history of sexual abuse to substance use problems to offspring victimization was significant (standardized mediated path [ab] = .07, 95% CI [.02, .14]; effect size = .26), as was the mediated pathway from maternal history of physical abuse to substance use problems to offspring victimization (standardized mediated path [ab] = .05, 95% CI [.01, .11]; effect size = .19). There was no significant mediated pathway from maternal history of neglect. Findings are discussed in terms of specific implications for child maltreatment prevention, including the importance of assessment and early intervention for maternal history of maltreatment and substance use problems, targeting women with maltreatment histories for substance use services, and integrating child welfare and parenting programs with substance use treatment.

History of Science and History of Philologies.

PubMed

Daston, Lorraine; Most, Glenn W

2015-06-01

While both the sciences and the humanities, as currently defined, may be too heterogeneous to be encompassed within a unified historical framework, there is good reason to believe that the history of science and the history of philologies both have much to gain by joining forces. This collaboration has already yielded striking results in the case of the history of science and humanist learning in early modern Europe. This essay argues that first, philology and at least some of the sciences (e.g., astronomy) remained intertwined in consequential ways well into the modern period in Western cultures; and second, widening the scope of inquiry to include other philological traditions in non-Western cultures offers rich possibilities for a comparative history of learned practices. The focus on practices is key; by shifting the emphasis from what is studied to how it is studied, deep commonalities emerge among disciplines--and intellectual traditions--now classified as disparate.

A Regeneratively Cooled Thrust Chamber For The Fastrac Engine

NASA Technical Reports Server (NTRS)

Brown, Kendall K.; Sparks, Dave; Woodcock, Gordon

2000-01-01

Abstract This paper presents the development of a low-cost, regeneratively-cooled thrust chamber for the Fastrac engine. The chamber was fabricated using hydraformed copper tubing to form the coolant jacket and wrapped with a fiber reinforced polymer composite Material to form a structural jacket. The thrust chamber design and fabrication approach was based upon Space America. Inc.'s 12,000 lb regeneratively-cooled LOX/kerosene rocket engine. Fabrication of regeneratively cooled thrust chambers by tubewall construction dates back to the early US ballistic missile programs. The most significant innovations in this design was the development of a low-cost process for fabrication from copper tubing (nickel alloy was the usual practice) and use of graphite composite overwrap as the pressure containment, which yields an easily fabricated, lightweight pressure jacket around the copper tubes A regeneratively-cooled reusable thrust chamber can benefit the Fastrac engine program by allowing more efficient (cost and scheduler testing). A proof-of-concept test article has been fabricated and will he tested at Marshall Space Flight Center in the late Summer or Fall of 2000.

Temperature profiles of different cooling methods in porcine pancreas procurement.

PubMed

Weegman, Bradley P; Suszynski, Thomas M; Scott, William E; Ferrer Fábrega, Joana; Avgoustiniatos, Efstathios S; Anazawa, Takayuki; O'Brien, Timothy D; Rizzari, Michael D; Karatzas, Theodore; Jie, Tun; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

2014-01-01

Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. This study examines the effect of four different cooling Methods on core porcine pancreas temperature (n = 24) and histopathology (n = 16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all three cooling Methods. Surface cooling alone (Method A) gradually decreased core pancreas temperature to <10 °C after 30 min. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15-20 °C within the first 2 min of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (P = 0.36). Histological scores were different between the cooling Methods (P = 0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (P = 0.02) and Methods A and D (P = 0.02), but not between Methods C and D (P = 0.95), which may highlight the importance of early cooling using an intraductal infusion. In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature profiles during procurement and

Temperature Profiles of Different Cooling Methods in Porcine Pancreas Procurement

PubMed Central

Weegman, Brad P.; Suszynski, Thomas M.; Scott, William E.; Ferrer, Joana; Avgoustiniatos, Efstathios S.; Anazawa, Takayuki; O’Brien, Timothy D.; Rizzari, Michael D.; Karatzas, Theodore; Jie, Tun; Sutherland, David ER.; Hering, Bernhard J.; Papas, Klearchos K.

2014-01-01

Background Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. Methods This study examines the effect of 4 different cooling Methods on core porcine pancreas temperature (n=24) and histopathology (n=16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all 3 cooling Methods. Results Surface cooling alone (Method A) gradually decreased core pancreas temperature to < 10 °C after 30 minutes. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15–20 °C within the first 2 minutes of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (p=0.36). Histological scores were different between the cooling Methods (p=0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (p=0.02) and Methods A and D (p=0.02), but not between Methods C and D (p=0.95), which may highlight the importance of early cooling using an intraductal infusion. Conclusions In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature

Microwave tumor ablation: cooperative academic-industry development of a high-power gas-cooled system with early clinical results

NASA Astrophysics Data System (ADS)

Brace, Christopher L.; Ziemlewicz, Timothy J.; Schefelker, Rick; Hinshaw, J. L.; Lubner, Meghan G.; Lee, Fred T.

2013-02-01

Microwave tumor ablation continues to evolve into a viable treatment option for many cancers. Current systems are poised to supplant radiofrequency ablation as the dominant percutaneous thermal therapy. Here is provided an overview of technical details and early clinical results with a high-powered, gas-cooled microwave ablation system. The system was developed with academic-industry collaboration using federal and private funding. The generator comprises three synchronous channels that each produce up to 140W at 2.45GHz. A mountable power distribution module facilitates CT imaging guidance and monitoring and reduces clutter in the sterile field. Cryogenic carbon-dioxide cools the coaxial applicator, permitting a thin applicator profile (~1.5 mm diameter) and high power delivery. A total of 106 liver tumors were treated (96 malignant, 10 benign) from December 2010 to June 2012 at a single academic institution. Mean tumor size +/- standard deviation was 2.5+/-1.3cm (range 0.5-13.9cm). Treatment time was 5.4+/-3.3min (range 1-20min). Median follow-up was 6 months (range 1-16 months). Technical success was reported in 100% of cases. Local tumor progression was noted in 4/96 (4.3%) of malignancies. The only major complication was a pleural effusion that was treated with thoracentesis. Microwave ablation with this system is an effective treatment for liver cancer. Compared to previous data from the same institution, these results suggest an increased efficacy and equivalent safety to RF ablation. Additional data from the lung and kidney support this conclusion.

Novel cardiovascular biomarkers in women with a history of early preeclampsia.

PubMed

Drost, José T; Maas, Angela H E M; Holewijn, Suzanne; Joosten, Leo A B; van Eyck, Jim; van der Schouw, Yvonne T; de Graaf, Jacqueline

2014-11-01

Women with a history of preeclampsia are at increased risk for future cardiovascular disease. Determination of cardiovascular biomarkers may be useful to understand the pathophysiological mechanism of cardiovascular disease development in these women. We performed an analysis in the Preeclampsia Risk EValuation in FEMales study, a retrospective cohort consisting of 339 women with a history of early preeclampsia and 332 women after normotensive pregnancy. Women attended a follow-up visit ten years after the index pregnancy. A subset of 8 different cardiovascular biomarkers was investigated, reflecting inflammatory, metabolic, thrombotic and endothelial function markers. Associations between PE and these novel biomarkers were analyzed by linear regression analysis and adjusted for traditional cardiovascular risk factors. Mean age of 671 women of the PREVFEM cohort was 39 years and women were on average 10 years post index pregnancy. Women post preeclampsia had significantly higher levels of SE-selectin (adjusted difference 4.55, 99%CI 0.37; 8.74) and PAPPA (adjusted difference 19.08; 99%CI 13.18; 24.99), whereas ApoB (adjusted difference -0.23 99%CI -0.32; -0.14) was inversely associated with preeclampsia, compared to women with a previous normotensive pregnancy. Adiponectin, leptin, sICAM-1, sVCAM-1 and PAI-1 were not different between both groups. We demonstrated an independent association of preeclampsia with SE-selectin and PAPPA (markers of vascular dysfunction), which may contribute to future cardiovascular events in women post preeclampsia. However, ApoB (an apolipoprotein) was significantly lower and could point at a protective mechanism in our PE study women. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Preserving History: The Construction of History in the K-16 Classroom

ERIC Educational Resources Information Center

Waring, Scott Monroe

2011-01-01

What and how to teach in the K-16 classroom history has been a perennial and, at times, heated debate. Beginning as early as 1892, the question of what knowledge is of the most worth and what should be the central function of the history curriculum became a focus of many interested in education. It was felt that the teachers needed to move away…

Diverging Histories of the Liberty Creek and Iceberg Lake Blueschist Bodies, south central Alaska

NASA Astrophysics Data System (ADS)

Day, E. M.; Pavlis, T. L.; Amato, J. M.

2011-12-01

New studies of the Liberty Creek and Iceberg Lake blueschist bodies of south central Alaska indicate that despite structural similarities, these blueschist bodies are derived from a different protolith and were metamorphosed to blueschist facies at distinctly different times. Both blueschists are located just south of the Border Ranges Fault (BRF) within outcrop belts of the McHugh Complex, a low-grade mélange assemblage that is now known from detrital zircon studies to consist of two distinct assemblages: a Jurassic to Earliest Cretaceous assemblage and a Late Cretaceous assemblage. The BRF is a megathrust system that represents the Late Triassic-Early Jurassic initiation of southern Alaskan subduction. Large scale (1:24,000) mapping revealed similar fabric overprint histories, epitomized by a previously undescribed youngest vertical N-S trending crenulation cleavage in both blueschist bodies which implies a structural correlation despite their separation of ~100 kilometers along strike. Despite structural similarities detrital zircon studies show that the Liberty Creek and Iceberg Lake blueschists do not have a similar maximum age of deposition. Thirteen samples from the Iceberg Lake blueschist were processed, none of which produced detrital zircons. Samples from the McHugh Complex greenschists that surround the Iceberg Lake blueschist produced numerous zircons indicating a Late Jurassic (~160 Ma) maximum age of deposition. Three out of sixteen samples from the Liberty creek blueschist produced detrital zircons indicating maximum depositional ages ranging from Late Jurassic (~160.1 Ma, n=64 grains; ~152.25 Ma, n=68 grains) to Early Cretaceous (~137.1 Ma, n=95 grains). The Late Jurassic dates are consistent with maximum depositional ages determined by Amato and Pavlis (2010) for McHugh Complex rocks along Turnagain Arm near Anchorage, AK. Sisson and Onstott (1986) reported a metamorphic cooling age of 185 Ma for the Iceberg Lake blueschist, thus, although no

Rethinking the early history of post-Vygotskian psychology: the case of the Kharkov school.

PubMed

Yasnitsky, Anton; Ferrari, Michel

2008-05-01

Between the death of Vygotsky in 1934 and the discovery of Vygotsky's work in the West in 1962, Vygotskian psychology was developed through research done by the first generation of Vygotsky's students and their followers, primarily associated with the Kharkov School. Surprisingly, these studies carried out in the 1930s, of great importance for the development of virtually all subsequent Vygotskian psychology, still remain largely unknown; this represents a significant gap in understanding the history of Vygotskian psychology as an empirical study of consciousness. This paper provides a systematic overview of the research agenda of the Kharkov group between 1931 and 1941 and provides new insights into the early development of Vygotskian psychology.

Confirmation of shutdown cooling effects

NASA Astrophysics Data System (ADS)

Sato, Kotaro; Tabuchi, Masato; Sugimura, Naoki; Tatsumi, Masahiro

2015-12-01

After the Fukushima accidents, all nuclear power plants in Japan have gradually stopped their operations and have long periods of shutdown. During those periods, reactivity of fuels continues to change significantly especially for high-burnup UO2 fuels and MOX fuels due to radioactive decays. It is necessary to consider these isotopic changes precisely, to predict neutronics characteristics accurately. In this paper, shutdown cooling (SDC) effects of UO2 and MOX fuels that have unusual operation histories are confirmed by the advanced lattice code, AEGIS. The calculation results show that the effects need to be considered even after nuclear power plants come back to normal operation.

Prevalence study of Simkania negevensis in cooling towers in Spain.

PubMed

Pérez, Leonardo Martín; Codony, Francesc; Ríos, Karina; Adrados, Bárbara; Fittipaldi, Mariana; De Dios, Gregori; Peñuela, Gustavo; Morató, Jordi

2011-06-01

Simkania negevensis is an obligate intracellular bacterium grouped into the order Chlamydiales. This new amoeba-resistant intracellular bacterium might represent a novel etiologic agent of bronchiolitis and community-acquired pneumonia and occurs in aquatic habitats such as drinking water and reclaimed wastewater. Another amoeba-related bacterium, Legionella pneumophila, is an etiologic agent of pneumonia transmitted by environmental aerosols or contaminated water/air cooling systems. These transmission pathways are important in the natural history of Legionellae infections and possibly other intracellular microorganisms such as Parachlamydiaceae; thus, understanding the feasibility of Simkania infection by these routes is relevant. In the present work, we investigated the prevalence of this newly identified pathogenic bacterium in cooling towers by quantitative PCR (qPCR) and its possible relationship with Legionella pneumophila co-infection. Our results show Simkania detection in 2 of 70 cooling towers analyzed. To our knowledge, this report is the first describing Simkania negevensis detection in this category of environmental water samples.

(See symbol in text) in early modern discussions of the passions: Stoicism, Christianity and natural history.

PubMed

Kraye, Jill

2012-01-01

This paper examines the reception of the Stoic theory of the passions in the early modern period, highlighting various differences between the way notions such as (see symbol in text) (complete freedom from passions) and(see symbol in text) (pre-passions) were handled and interpreted by Continental and English authors. Both groups were concerned about the compatibility of Stoicism with Christianity, but came to opposing conclusions; and while the Continental scholars drew primarily on ancient philosophical texts, the English ones relied, in addition, on experience and observation, developing a natural history of the passions.

Challenges and Opportunities in Gen3 Embedded Cooling with High-Quality Microgap Flow

NASA Technical Reports Server (NTRS)

Bar-Cohen, Avram; Robinson, Franklin L.; Deisenroth, David C.

2018-01-01

Gen3, Embedded Cooling, promises to revolutionize thermal management of advanced microelectronic systems by eliminating the sequential conductive and interfacial thermal resistances which dominate the present 'remote cooling' paradigm. Single-phase interchip microfluidic flow with high thermal conductivity chips and substrates has been used successfully to cool single transistors dissipating more than 40kW/sq cm, but efficient heat removal from transistor arrays, larger chips, and chip stacks operating at these prodigious heat fluxes would require the use of high vapor fraction (quality), two-phase cooling in intra- and inter-chip microgap channels. The motivation, as well as the challenges and opportunities associated with evaporative embedded cooling in realistic form factors, is the focus of this paper. The paper will begin with a brief review of the history of thermal packaging, reflecting the 70-year 'inward migration' of cooling technology from the computer-room, to the rack, and then to the single chip and multichip module with 'remote' or attached air- and liquid-cooled coldplates. Discussion of the limitations of this approach and recent results from single-phase embedded cooling will follow. This will set the stage for discussion of the development challenges associated with application of this Gen3 thermal management paradigm to commercial semiconductor hardware, including dealing with the effects of channel length, orientation, and manifold-driven centrifugal acceleration on the governing behavior.

Magnetic neutron star cooling and microphysics

NASA Astrophysics Data System (ADS)

Potekhin, A. Y.; Chabrier, G.

2018-01-01

Aims: We study the relative importance of several recent updates of microphysics input to the neutron star cooling theory and the effects brought about by superstrong magnetic fields of magnetars, including the effects of the Landau quantization in their crusts. Methods: We use a finite-difference code for simulation of neutron-star thermal evolution on timescales from hours to megayears with an updated microphysics input. The consideration of short timescales (≲1 yr) is made possible by a treatment of the heat-blanketing envelope without the quasistationary approximation inherent to its treatment in traditional neutron-star cooling codes. For the strongly magnetized neutron stars, we take into account the effects of Landau quantization on thermodynamic functions and thermal conductivities. We simulate cooling of ordinary neutron stars and magnetars with non-accreted and accreted crusts and compare the results with observations. Results: Suppression of radiative and conductive opacities in strongly quantizing magnetic fields and formation of a condensed radiating surface substantially enhance the photon luminosity at early ages, making the life of magnetars brighter but shorter. These effects together with the effect of strong proton superfluidity, which slows down the cooling of kiloyear-aged neutron stars, can explain thermal luminosities of about a half of magnetars without invoking heating mechanisms. Observed thermal luminosities of other magnetars are still higher than theoretical predictions, which implies heating, but the effects of quantizing magnetic fields and baryon superfluidity help to reduce the discrepancy.

Effects of maternal history of depression and early life maltreatment on children's health-related quality of life.

PubMed

Dittrich, Katja; Fuchs, Anna; Bermpohl, Felix; Meyer, Justus; Führer, Daniel; Reichl, Corinna; Reck, Corinna; Kluczniok, Dorothea; Kaess, Michael; Hindi Attar, Catherine; Möhler, Eva; Bierbaum, Anna-Lena; Zietlow, Anna-Lena; Jaite, Charlotte; Winter, Sibylle Maria; Herpertz, Sabine C; Brunner, Romuald; Bödeker, Katja; Resch, Franz

2018-01-01

There is a well-established link between maternal depression and child mental health. Similar effects have been found for maternal history of early life maltreatment (ELM). However, studies investigating the relationship of children's quality of life and maternal depression are scarce and none have been conducted for the association with maternal ELM. The aim of the present study was to investigate the effects of maternal history of ELM and depression on children's health-related quality of life and to identify mediating factors accounting for these effects. Our study involved 194 mothers with and without history of depression and/or ELM and their children between five and 12 years. Children's health-related quality of life was assessed by maternal proxy- and child self-ratings using the KIDSCREEN. We considered maternal sensitivity and maternal parenting stress as potential mediators. We found an effect of maternal history of depression but not of maternal history of ELM on health-related quality of life. Maternal stress and sensitivity mediated the effects of maternal depression on child global health-related quality of life, as well as on the dimensions Autonomy & Parent Relation, School Environment (maternal and child rating), and Physical Wellbeing (child rating). Due to the cross-sectional design of the study, causal interpretations must be made with caution. Some scales yielded low internal consistency. Maternal impairments in areas of parenting which possibly developed during acute depression persist even after remission of acute affective symptoms. Interventions should target parenting stress and sensitivity in parents with prior depression. Copyright © 2017 Elsevier B.V. All rights reserved.

Earliest evidence of modern human life history in North African early Homo sapiens.

PubMed

Smith, Tanya M; Tafforeau, Paul; Reid, Donald J; Grün, Rainer; Eggins, Stephen; Boutakiout, Mohamed; Hublin, Jean-Jacques

2007-04-10

Recent developmental studies demonstrate that early fossil hominins possessed shorter growth periods than living humans, implying disparate life histories. Analyses of incremental features in teeth provide an accurate means of assessing the age at death of developing dentitions, facilitating direct comparisons with fossil and modern humans. It is currently unknown when and where the prolonged modern human developmental condition originated. Here, an application of x-ray synchrotron microtomography reveals that an early Homo sapiens juvenile from Morocco dated at 160,000 years before present displays an equivalent degree of tooth development to modern European children at the same age. Crown formation times in the juvenile's macrodont dentition are higher than modern human mean values, whereas root development is accelerated relative to modern humans but is less than living apes and some fossil hominins. The juvenile from Jebel Irhoud is currently the oldest-known member of Homo with a developmental pattern (degree of eruption, developmental stage, and crown formation time) that is more similar to modern H. sapiens than to earlier members of Homo. This study also underscores the continuing importance of North Africa for understanding the origins of human anatomical and behavioral modernity. Corresponding biological and cultural changes may have appeared relatively late in the course of human evolution.

An organismal concept for Sengelia radicans gen. et sp. nov. - morphology and natural history of an Early Devonian lycophyte.

PubMed

Matsunaga, Kelly K S; Tomescu, Alexandru M F

2017-05-01

Fossil plants are found as fragmentary remains and understanding them as natural species requires assembly of whole-organism concepts that integrate different plant parts. Such concepts are essential for incorporating fossils in hypotheses of plant evolution and phylogeny. Plants of the Early Devonian are crucial to reconstructing the initial radiation of tracheophytes, yet few are understood as whole organisms. This study assembles a whole-plant concept for the Early Devonian lycophyte Sengelia radicans gen. et sp. nov., based on morphometric data and taphonomic observations from >1000 specimens collected in the Beartooth Butte Formation (Wyoming, USA). Sengelia radicans occupies a key position between stem-group and derived lycophyte lineages. Sengelia had a rooting system of downward-growing root-bearing stems, formed dense monotypic mats of prostrate shoots in areas that experienced periodic flooding, and was characterized by a life-history strategy adapted for survival after floods, dominated by clonality, and featuring infrequent sexual reproduction. Sengelia radicans is the oldest among the very few early tracheophytes for which a detailed, rigorous whole-plant concept integrates morphology, growth habit, life history and growth environment. This plant adds to the diversity of body plans documented among lycophytes and may help elucidate patterns of morphological evolution in the clade. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Cooling Flows

NASA Astrophysics Data System (ADS)

Fabian, A.; Murdin, P.

2000-11-01

A subsonic cooling flow occurs when the hot gaseous atmosphere of a galaxy, group or cluster of galaxies cools slowly. Such atmospheres occur as a result of gas having fallen into the DARK MATTER well of the object and heated by gravitational energy release. A dominant cooling process is the emission of radiation by the gas. As cooling proceeds the gas sinks further in the potential well, giving ...

Cooling rate effects in sodium silicate glasses: Bridging the gap between molecular dynamics simulations and experiments

NASA Astrophysics Data System (ADS)

Li, Xin; Song, Weiying; Yang, Kai; Krishnan, N. M. Anoop; Wang, Bu; Smedskjaer, Morten M.; Mauro, John C.; Sant, Gaurav; Balonis, Magdalena; Bauchy, Mathieu

2017-08-01

Although molecular dynamics (MD) simulations are commonly used to predict the structure and properties of glasses, they are intrinsically limited to short time scales, necessitating the use of fast cooling rates. It is therefore challenging to compare results from MD simulations to experimental results for glasses cooled on typical laboratory time scales. Based on MD simulations of a sodium silicate glass with varying cooling rate (from 0.01 to 100 K/ps), here we show that thermal history primarily affects the medium-range order structure, while the short-range order is largely unaffected over the range of cooling rates simulated. This results in a decoupling between the enthalpy and volume relaxation functions, where the enthalpy quickly plateaus as the cooling rate decreases, whereas density exhibits a slower relaxation. Finally, we show that, using the proper extrapolation method, the outcomes of MD simulations can be meaningfully compared to experimental values when extrapolated to slower cooling rates.

Cooling Spheres and Accumulating Lead: The History of Attempts to Date the Earth's Formation.

ERIC Educational Resources Information Center

Brush, Stephen G.

1987-01-01

Presents a chronology of scientific efforts designed to determine the age of the earth. Summarizes scientists' attempts at dating the planet's formation, including the examination of lead in the environment, the calculation of the earth's cooling temperature and time, the study of geological sedimentation and the analysis of moon rocks. (TW)

Multifrequency VLA observations of PKS 0745 - 191 - The archetypal 'cooling flow' radio source?

NASA Technical Reports Server (NTRS)

Baum, S. A.; O'Dea, C. P.

1991-01-01

Ninety-, 20-, 6- and 2-cm VLA observations of the high-radio-luminosity cooling-flow radio source PKS 0745 - 191 are presented. The radio source was found to have a core with a very steep spectrum (alpha is approximately -1.5) and diffuse emission with an even steeper spectrum (alpha is approximately -1.5 to -2.3) without clear indications of the jets, hotspots, or double lobes found in the other radio sources of comparable luminosity. It is inferred that the energy to power the radio source comes from the central engine, but the source's structure may be heavily influenced by the past history of the galaxy and the inflowing intracluster medium. It is shown that, while the radio source is energetically unimportant for the cluster as a whole, it is important on the scale of the cooling flow. The mere existence of cosmic rays and magnetic fields within a substantial fraction of the volume inside the cooling radius has important consequences for cooling-flow models.

The evolution of cooling flows. I - Self-similar cluster flows. [of gas in intergalactic medium

NASA Technical Reports Server (NTRS)

Chevalier, Roger A.

1987-01-01

The evolution of a cooling flow from an initial state of hydrostatic equilibrium in a cluster of galaxies is investigated. After gas mass and energy are injected into the cluster at an early phase, the gas approaches hydrostatic equilibrium over most of the cluster and cooling becomes important in the dense central regions. As time passes, cooling strongly affects an increasing amount of gas. The effects of mass removal from the flow, the inclusion of magnetic or cosmic-ray pressure, and heat conduction are considered individually.

Some consequences of a liquid water saturated regolith in early Martian history

NASA Technical Reports Server (NTRS)

Fuller, A. O.; Hargraves, R. B.

1978-01-01

Flooding of low-lying areas of the Martian regolith may have occurred early in the planet's history when a comparatively dense primitive atmosphere existed. If this model is valid, the following are some pedogenic and mineralogical consequences to be expected. Fluctuation of the water table in response to any seasonal or longer term causes would have resulted in precipitation of ferric oxyhydroxides with the development of a vesicular duricrust (or hardpan). Disruption of such a crust by scarp undercutting or frost heaving accompanied by wind deflation of fines could account for the boulders visible on Utopia Planitia in the vicinity of the second Viking lander site. Laboratory and field evidence on earth suggests that under weakly oxidizing conditions lepidocrocite (rather than goethite) would have preferentially formed in the Martian regolith from the weathering of ferrous silicates, accompanied by montmorillonite, nontronite, and cronstedtite. Maghemite may have formed as a low-temperature dehydrate of lepidocrocite or directly from ferrous precursors.

Thermal History of CBb Chondrules and Cooling Rate Distributions of Ejecta Plumes

NASA Astrophysics Data System (ADS)

Hewins, R. H.; Condie, C.; Morris, M.; Richardson, M. L. A.; Ouellette, N.; Metcalf, M.

2018-03-01

It has been proposed that some meteorites, CB and CH chondrites, contain material formed as a result of a protoplanetary collision during accretion. Their melt droplets (chondrules) and FeNi metal are proposed to have formed by evaporation and condensation in the resulting impact plume. We observe that the skeletal olivine (SO) chondrules in CBb chondrites have a blebby texture and an enrichment in refractory elements not found in normal chondrules. Because the texture requires complete melting, their maximum liquidus temperature of 1928 K represents a minimum temperature for the putative plume. Dynamic crystallization experiments show that the SO texture can be created only by brief reheating episodes during crystallization, giving a partial dissolution of olivine. The ejecta plume formed in a smoothed particle hydrodynamics simulation served as the basis for 3D modeling with the adaptive mesh refinement code FLASH4.3. Tracer particles that move with the fluid cells are used to measure the in situ cooling rates. Their cooling rates are ∼10,000 K hr‑1 briefly at peak temperature and, in the densest regions of the plume, ∼100 K hr‑1 for 1400–1600 K. A small fraction of cells is seen to be heating at any one time, with heating spikes explained by the compression of parcels of gas in a heterogeneous patchy plume. These temperature fluctuations are comparable to those required in crystallization experiments. For the first time, we find an agreement between experiments and models that supports the plume model specifically for the formation of CBb chondrules.

DNA fingerprinting on trial: the dramatic early history of a new forensic technique.

PubMed

Aronson, Jay D

2005-09-01

The early history of "DNA fingerprinting" in the UK might have been different were it not for the accounts of two dramatic courtroom trials, made by the participants and the media, in the mid-1980s. But these reports, which misrepresented the importance DNA evidence had in the trials, left a strong impression on the British public and on judges on both sides of the Atlantic. These trials, widely considered to be the first "victories" for DNA fingerprinting, have been frequently cited as proof of the utility and reliability of the technique, in both the UK and beyond. But in reality, it was the threat of DNA evidence being used rather than the integrity or validity of it that resolved these cases. At that time, DNA fingerprinting was still in its infancy, an untried and untested technology.

Experimental evaluation of cooling efficiency of the high performance cooling device

NASA Astrophysics Data System (ADS)

Nemec, Patrik; Malcho, Milan

2016-06-01

This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heat of electronic components in range from 250 to 740 W.

Asteroid Impacts, Microbes, and the Cooling of the Atmosphere

NASA Technical Reports Server (NTRS)

Oberbeck, Verne R.; Mancinelli, Rocco L.

1994-01-01

Earth's surface temperature constrained microbial evolution, according to Schwartzman et al. (1993). Their hypothesis states that the maximal temperature that extant organisms of a given type tolerate is the surface temperature occurring when that type of organism arose. Schwartzman and his colleagues concluded that the temperature changed from 100 C to 50 C between 3.75 billion years ago (BYA) and 1 BYA. These temperatures are consistent with those derived from oxygen isotope ratios in ancient sediments (Karhu and Epstein 1986, Knauth and Lowe 1978). The 100 C surface temperature they derive for 3.75 BYA is also the same as Earth's surface temperature 4.4 BYA (Kosting and Ackerman 1986). In this article, we address the cause of the delay in surface cooling until 3.75 BYA, and we explore the implications for microbial evolution of a high temperature on early Earth. We propose that three effects of the early heavy bombardment of Earth by asteroids and comets, until 3.8 BYA, could have delayed onset of surface cooling.

Onset and establishment of diazotrophs and other bacterial associates in the early life history stages of the coral Acropora millepora.

PubMed

Lema, Kimberley A; Bourne, David G; Willis, Bette L

2014-10-01

Early establishment of coral-microbial symbioses is fundamental to the fitness of corals, but comparatively little is known about the onset and succession of bacterial communities in their early life history stages. In this study, bacterial associates of the coral Acropora millepora were characterized throughout the first year of life, from larvae and 1-week-old juveniles reared in laboratory conditions in the absence of the dinoflagellate endosymbiont Symbiodinium to field-outplanted juveniles with established Symbiodinium symbioses, and sampled at 2 weeks and at 3, 6 and 12 months. Using an amplicon pyrosequencing approach, the diversity of both nitrogen-fixing bacteria and of bacterial communities overall was assessed through analysis of nifH and 16S rRNA genes, respectively. The consistent presence of sequences affiliated with diazotrophs of the order Rhizobiales (23-58% of retrieved nifH sequences; 2-12% of 16S rRNA sequences), across all samples from larvae to 12-month-old coral juveniles, highlights the likely functional importance of this nitrogen-fixing order to the coral holobiont. Dominance of Roseobacter-affiliated sequences (>55% of retrieved 16S rRNA sequences) in larvae and 1-week-old juveniles, and the consistent presence of sequences related to Oceanospirillales and Altermonadales throughout all early life history stages, signifies their potential importance as coral associates. Increased diversity of bacterial communities once juveniles were transferred to the field, particularly of Cyanobacteria and Deltaproteobacteria, demonstrates horizontal (environmental) uptake of coral-associated bacterial communities. Although overall bacterial communities were dynamic, bacteria with likely important functional roles remain stable throughout early life stages of Acropora millepora. © 2014 John Wiley & Sons Ltd.

Modeling the early evolution of Vesta

NASA Astrophysics Data System (ADS)

Weisfeiler, Marie; Turcotte, Donald L.; Kellogg, Louise H.

2017-05-01

The early evolution of the asteroid Vesta has been extensively studied because of the availability of relevant data, especially important new studies of HED meteorites which originated from Vesta and the Dawn mission to Vesta in 2011-2012. These studies have concluded that an early melting episode led to the differentiation of Vesta into crust, mantle, and core. This melting episode is attributed to the decay of 26Al, which has a half-life of 7.17 × 105 yr. This heating produced a global magma ocean. Surface cooling of this magma ocean will produce a solid crust. In this paper, we propose a convective heat-transfer mechanism that effectively cools the asteroid when the degree of melting reaches about 50%. We propose that a cool solid surface crust, which is gravitationally unstable, will founder into the solid-liquid mix beneath and will very effectively transfer heat that prevents further melting of the interior. In this paper, we quantify this process. If Vesta had a very early formation, melting would commence at an age of about 1,30,000 yr, and solidification would occur at an age of about 10 Myr. If Vesta formed with a time delay greater than about 2 Myr, no melting would have occurred. An important result of our model is that the early melting episode is restricted to the first 10 Myr. This result is in good agreement with the radiometric ages of the HED meteorites.

High-Altitude Flight Cooling Investigation of a Radial Air-Cooled Engine

NASA Technical Reports Server (NTRS)

Manganiello, Eugene J; Valerino, Michael F; Bell, E Barton

1947-01-01

An investigation of the cooling of an 18-cylinder, twin-row, radial, air-cooled engine in a high-performance pursuit airplane has been conducted for variable engine and flight conditions at altitudes ranging from 5000 to 35,000 feet in order to provide a basis for predicting high-altitude cooling performance from sea-level or low altitude experimental results. The engine cooling data obtained were analyzed by the usual NACA cooling-correlation method wherein cylinder-head and cylinder-barrel temperatures are related to the pertinent engine and cooling-air variables. A theoretical analysis was made of the effect on engine cooling of the change of density of the cooling air across the engine (the compressibility effect), which becomes of increasing importance as altitude is increased. Good agreement was obtained between the results of the theoretical analysis and the experimental data.

Simulation of the Continuous Casting and Cooling Behavior of Metallic Glasses

PubMed Central

Pei, Zhipu; Ju, Dongying

2017-01-01

The development of melt spinning technique for preparation of metallic glasses was summarized. The limitations as well as restrictions of the melt spinning embodiments were also analyzed. As an improvement and variation of the melt spinning method, the vertical-type twin-roll casting (VTRC) process was discussed. As the thermal history experienced by the casting metals to a great extent determines the qualities of final products, cooling rate in the quenching process is believed to have a significant effect on glass formation. In order to estimate the ability to produce metallic glasses by VTRC method, temperature and flow phenomena of the melt in molten pool were computed, and cooling rates under different casting conditions were calculated with the simulation results. Considering the fluid character during casting process, the material derivative method based on continuum theory was adopted in the cooling rate calculation. Results show that the VTRC process has a good ability in continuous casting metallic glassy ribbons. PMID:28772779

Simulation of the Continuous Casting and Cooling Behavior of Metallic Glasses.

PubMed

Pei, Zhipu; Ju, Dongying

2017-04-17

The development of melt spinning technique for preparation of metallic glasses was summarized. The limitations as well as restrictions of the melt spinning embodiments were also analyzed. As an improvement and variation of the melt spinning method, the vertical-type twin-roll casting (VTRC) process was discussed. As the thermal history experienced by the casting metals to a great extent determines the qualities of final products, cooling rate in the quenching process is believed to have a significant effect on glass formation. In order to estimate the ability to produce metallic glasses by VTRC method, temperature and flow phenomena of the melt in molten pool were computed, and cooling rates under different casting conditions were calculated with the simulation results. Considering the fluid character during casting process, the material derivative method based on continuum theory was adopted in the cooling rate calculation. Results show that the VTRC process has a good ability in continuous casting metallic glassy ribbons.

Crystallization, flow and thermal histories of lunar and terrestrial compositions

NASA Technical Reports Server (NTRS)

Uhlmann, D. R.

1979-01-01

Contents: a kinetic treatment of glass formation; effects of nucleating heterogeneities on glass formation; glass formation under continuous cooling conditions; crystallization statistics; kinetics of crystal nucleation; diffusion controlled crystal growth; crystallization of lunar compositions; crystallization between solidus and liquidus; crystallization on reheating a glass; temperature distributions during crystallization; crystallization of anorthite and anorthite-albite compositions; effect of oxidation state on viscosity; diffusive creep and viscous flow; high temperature flow behavior of glass-forming liquids, a free volume interpretation; viscous flow behavior of lunar compositions; thermal history of orange soil material; breccias formation by viscous sintering; viscous sintering; thermal histories of breccias; solute partitioning and thermal history of lunar rocks; heat flow in impact melts; and thermal histories of olivines.

Temperatures and cooling rates recorded in REE in coexisting pyroxenes in ophiolitic and abyssal peridotites

NASA Astrophysics Data System (ADS)

Dygert, Nick; Liang, Yan

2015-06-01

Mantle peridotites from ophiolites are commonly interpreted as having mid-ocean ridge (MOR) or supra-subduction zone (SSZ) affinity. Recently, an REE-in-two-pyroxene thermometer was developed (Liang et al., 2013) that has higher closure temperatures (designated as TREE) than major element based two-pyroxene thermometers for mafic and ultramafic rocks that experienced cooling. The REE-in-two-pyroxene thermometer has the potential to extract meaningful cooling rates from ophiolitic peridotites and thus shed new light on the thermal history of the different tectonic regimes. We calculated TREE for available literature data from abyssal peridotites, subcontinental (SC) peridotites, and ophiolites around the world (Alps, Coast Range, Corsica, New Caledonia, Oman, Othris, Puerto Rico, Russia, and Turkey), and augmented the data with new measurements for peridotites from the Trinity and Josephine ophiolites and the Mariana trench. TREE are compared to major element based thermometers, including the two-pyroxene thermometer of Brey and Köhler (1990) (TBKN). Samples with SC affinity have TREE and TBKN in good agreement. Samples with MOR and SSZ affinity have near-solidus TREE but TBKN hundreds of degrees lower. Closure temperatures for REE and Fe-Mg in pyroxenes were calculated to compare cooling rates among abyssal peridotites, MOR ophiolites, and SSZ ophiolites. Abyssal peridotites appear to cool more rapidly than peridotites from most ophiolites. On average, SSZ ophiolites have lower closure temperatures than abyssal peridotites and many ophiolites with MOR affinity. We propose that these lower temperatures can be attributed to the residence time in the cooling oceanic lithosphere prior to obduction. MOR ophiolites define a continuum spanning cooling rates from SSZ ophiolites to abyssal peridotites. Consistent high closure temperatures for abyssal peridotites and the Oman and Corsica ophiolites suggests hydrothermal circulation and/or rapid cooling events (e.g., normal

Southwest USA Exhumation History Recorded Below the Great Unconformity

NASA Astrophysics Data System (ADS)

Heizler, M. T.; Karlstrom, K. E.

2002-05-01

The Southwestern USA Precambrian terranes preserve a long and variable exhumation history that can be tracked using thermochronological methods. This exhumation history is controlled on two interrelated scales. At first order, it is recognized that 1.7 to 1.4 Ga mid-crustal (10 km, 2-4 kbar) rocks were ultimately exhumed and reside below unconformities of variable age. In Arizona, Mesoproterozoic Apache Group and Neoproterozoic Supergroup sedimentary rocks lie directly on basement and thus indicate exhumation of some regions relatively soon following the 1.4 Ga events. In the Rocky Mountains of Colorado and the Rio Grande rift uplifts of New Mexico, basement is generally overlain by Cambrian to Mississippian strata. The unconformities are useful markers of net exhumation; however do not reveal a time-integrated path. Using published, and hundreds of new 40Ar/39Ar analyses of hornblende, muscovite, biotite and K-feldspar, and a growing U/Pb accessory mineral thermochronology database, we are extracting exhumation information with great detail. The thermochronological data continue to support the claim that relatively low net exhumation occurred following 1.7 to 1.6 Ga accretion of volcanic arc terranes to the southern margin of Laurentia. Mid-crustal (2-4 kbar) rocks stabilized soon after accretion, whereas in some regions like the Upper Granite Gorge, Grand Canyon deeper (6 kbar) metamorphic terranes decompressed to 3 kbar before stabilization. The cooling history of these mid-crustal rocks post 1.65 Ga remains somewhat unknown. Overall slow-cooling models (550 \\deg C to 300 \\deg C from 1.7 to 1.4 Ga) require high geothermal gradients in order to maintain 10 km deep rocks at high temperatures for 100's of Ma. Alternatively, isobaric cooling models to more normal geothermal gradients (i.e. 25 \\deg C/km) at ca. 1.65 Ga require later (1.4 Ga) thermal pulses and/or Mesoproterozoic vertical displacements to explain highly discordant thermochronological data. Either

Forming chondrules in impact splashes. I. Radiative cooling model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dullemond, Cornelis Petrus; Stammler, Sebastian Markus; Johansen, Anders

2014-10-10

The formation of chondrules is one of the oldest unsolved mysteries in meteoritics and planet formation. Recently an old idea has been revived: the idea that chondrules form as a result of collisions between planetesimals in which the ejected molten material forms small droplets that solidify to become chondrules. Pre-melting of the planetesimals by radioactive decay of {sup 26}Al would help produce sprays of melt even at relatively low impact velocity. In this paper we study the radiative cooling of a ballistically expanding spherical cloud of chondrule droplets ejected from the impact site. We present results from numerical radiative transfermore » models as well as analytic approximate solutions. We find that the temperature after the start of the expansion of the cloud remains constant for a time t {sub cool} and then drops with time t approximately as T ≅ T {sub 0}[(3/5)t/t {sub cool} + 2/5]{sup –5/3} for t > t {sub cool}. The time at which this temperature drop starts t {sub cool} depends via an analytical formula on the mass of the cloud, the expansion velocity, and the size of the chondrule. During the early isothermal expansion phase the density is still so high that we expect the vapor of volatile elements to saturate so that no large volatile losses are expected.« less

Early fire history near Seguin Falls, Ontario

Treesearch

Daniel C. Dey; Richard P. Guyette

1996-01-01

This report is one of a series of site-specfic fire histories being developed for red oak (Quercus rubra L.)-pine ecosystems in central Ontario. Collectively, these studies documents the role of fire in upland oak forests. this information also provides an ecological basis for developing silviculture prescriptions that use prescribed burning to...

Passive wall cooling panel with phase change material as a cooling agent

NASA Astrophysics Data System (ADS)

Majid, Masni A.; Tajudin, Rasyidah Ahmad; Salleh, Norhafizah; Hamid, Noor Azlina Abd

2017-11-01

The study was carried out to the determine performance of passive wall cooling panels by using Phase Change Materials as a cooling agent. This passive cooling system used cooling agent as natural energy storage without using any HVAC system. Eight full scale passive wall cooling panels were developed with the size 1500 mm (L) × 500 mm (W) × 100 mm (T). The cooling agent such as glycerine were filled in the tube with horizontal and vertical arrangement. The passive wall cooling panels were casting by using foamed concrete with density between 1200 kg/m3 - 1500 kg/m3. The passive wall cooling panels were tested in a small house and the differences of indoor and outdoor temperature was recorded. Passive wall cooling panels with glycerine as cooling agent in vertical arrangement showed the best performance with dropped of indoor air temperature within 3°C compared to outdoor air temperature. The lowest indoor air temperature recorded was 25°C from passive wall cooling panels with glycerine in vertical arrangement. From this study, the passive wall cooling system could be applied as it was environmental friendly and less maintenance.

Restaurant Food Cooling Practices†

PubMed Central

BROWN, LAURA GREEN; RIPLEY, DANNY; BLADE, HENRY; REIMANN, DAVE; EVERSTINE, KAREN; NICHOLAS, DAVE; EGAN, JESSICA; KOKTAVY, NICOLE; QUILLIAM, DANIELA N.

2017-01-01

Improper food cooling practices are a significant cause of foodborne illness, yet little is known about restaurant food cooling practices. This study was conducted to examine food cooling practices in restaurants. Specifically, the study assesses the frequency with which restaurants meet U.S. Food and Drug Administration (FDA) recommendations aimed at reducing pathogen proliferation during food cooling. Members of the Centers for Disease Control and Prevention’s Environmental Health Specialists Network collected data on food cooling practices in 420 restaurants. The data collected indicate that many restaurants are not meeting FDA recommendations concerning cooling. Although most restaurant kitchen managers report that they have formal cooling processes (86%) and provide training to food workers on proper cooling (91%), many managers said that they do not have tested and verified cooling processes (39%), do not monitor time or temperature during cooling processes (41%), or do not calibrate thermometers used for monitoring temperatures (15%). Indeed, 86% of managers reported cooling processes that did not incorporate all FDA-recommended components. Additionally, restaurants do not always follow recommendations concerning specific cooling methods, such as refrigerating cooling food at shallow depths, ventilating cooling food, providing open-air space around the tops and sides of cooling food containers, and refraining from stacking cooling food containers on top of each other. Data from this study could be used by food safety programs and the restaurant industry to target training and intervention efforts concerning cooling practices. These efforts should focus on the most frequent poor cooling practices, as identified by this study. PMID:23212014

Restaurant food cooling practices.

PubMed

Brown, Laura Green; Ripley, Danny; Blade, Henry; Reimann, Dave; Everstine, Karen; Nicholas, Dave; Egan, Jessica; Koktavy, Nicole; Quilliam, Daniela N

2012-12-01

Improper food cooling practices are a significant cause of foodborne illness, yet little is known about restaurant food cooling practices. This study was conducted to examine food cooling practices in restaurants. Specifically, the study assesses the frequency with which restaurants meet U.S. Food and Drug Administration (FDA) recommendations aimed at reducing pathogen proliferation during food cooling. Members of the Centers for Disease Control and Prevention's Environmental Health Specialists Network collected data on food cooling practices in 420 restaurants. The data collected indicate that many restaurants are not meeting FDA recommendations concerning cooling. Although most restaurant kitchen managers report that they have formal cooling processes (86%) and provide training to food workers on proper cooling (91%), many managers said that they do not have tested and verified cooling processes (39%), do not monitor time or temperature during cooling processes (41%), or do not calibrate thermometers used for monitoring temperatures (15%). Indeed, 86% of managers reported cooling processes that did not incorporate all FDA-recommended components. Additionally, restaurants do not always follow recommendations concerning specific cooling methods, such as refrigerating cooling food at shallow depths, ventilating cooling food, providing open-air space around the tops and sides of cooling food containers, and refraining from stacking cooling food containers on top of each other. Data from this study could be used by food safety programs and the restaurant industry to target training and intervention efforts concerning cooling practices. These efforts should focus on the most frequent poor cooling practices, as identified by this study.

Distribution of early life history stages of fishes in selected pools of the upper Mississippi River

USGS Publications Warehouse

Holland, L.E.

1986-01-01

Effective management of the fishery resources of the Upper Mississippi River and successful mitigation of the loss of critical habitat depend in part on an understanding of the reproductive and early life history requirements of the affected fishes. However, little is known about the use of nursery areas by fishes in the river. Of the nearly 130 species identified in the adult ichthyofauna, only a few are represented proportionally in the available data on early life stages because study designs have not included consideration of the early stages, collection gears have not adequately sampled the young, and eggs and larvae of some species are difficult to sample by conventional approaches. For the species collected, information is available on seasonal variations in total densities, composition, and catch among different habitat types. However, the data are most accurate for species with buoyant early life stages, such as freshwater drum (Aplodinotus grunniens) and gizzard shad (Dorosoma cepedianum). Eggs and larvae of freshwater drum dominate collections made in the main channel, whereas other larval fishes are usually most abundant in backwater habitats. The species found there usually deposit eggs on the substrate or on vegetation. Habitat preferences (as indicated by relative abundance) often shift as development proceeds and physical and behavioral changes occur in the larvae. Only limited information is available on the distribution of larvae within habitats, but it is clear that variations within habitats are significant.

Rethinking Controls on the Long-Term Cenozoic Carbonate Compensation Depth: Case Studies across Late Paleocene - Early Eocene Warming and Late Eocene - Early Oligocene Cooling

NASA Astrophysics Data System (ADS)

Greene, S. E.; Ridgwell, A. J.; Schmidt, D. N.; Kirtland Turner, S.; Paelike, H.; Thomas, E.

2014-12-01

The carbonate compensation depth (CCD) is the depth below which negligible calcium carbonate is preserved in marine sediments. The long-term position of the CCD is often considered to be a powerful constraint on palaeoclimate and atmospheric CO2 concentration due to the requirement that carbonate burial balance riverine weathering over long timescales. The requirement that weathering and burial be in balance is clear, but it is less certain that burial compensates for changes in weathering via shoaling or deepening of the CCD. Because most carbonate burial occurs well above the CCD , changes in weathering fluxes may be primarily accommodated by increasing or decreasing carbonate burial at shallower depths, i.e., at or near the lysocline, the depth range over which carbonate dissolution markedly increases. Indeed, recent earth system modelling studies have suggested that the position of the CCD is relatively insensitive to changes in atmospheric pCO2. Additionally, studies have questioned the nature and strength of the relationship between the CCD, carbonate saturation state in the water column, and lysocline. To test the relationship between palaeoclimate and the location of the CCD, we reconstructed the global, long-term CCD behaviour across major Cenozoic climate transitions: the late Paleocene - early Eocene long-term warming trend (study interval ~58 to 49 Ma) and the late Eocene - early Oligocene cooling and glaciation (study interval ~38 to 27 Ma). We use Earth system modelling (GENIE) to explore the links between atmospheric pCO2 and the CCD, isolating and teasing apart the roles of total dissolved inorganic carbon, temperature, circulation, and productivity in determining the CCD.

The ATLAS3D Project - XXX. Star formation histories and stellar population scaling relations of early-type galaxies

NASA Astrophysics Data System (ADS)

McDermid, Richard M.; Alatalo, Katherine; Blitz, Leo; Bournaud, Frédéric; Bureau, Martin; Cappellari, Michele; Crocker, Alison F.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnović, Davor; Kuntschner, Harald; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Scott, Nicholas; Serra, Paolo; Weijmans, Anne-Marie; Young, Lisa M.

2015-04-01

We present the stellar population content of early-type galaxies from the ATLAS3D survey. Using spectra integrated within apertures covering up to one effective radius, we apply two methods: one based on measuring line-strength indices and applying single stellar population (SSP) models to derive SSP-equivalent values of stellar age, metallicity, and alpha enhancement; and one based on spectral fitting to derive non-parametric star formation histories, mass-weighted average values of age, metallicity, and half-mass formation time-scales. Using homogeneously derived effective radii and dynamically determined galaxy masses, we present the distribution of stellar population parameters on the Mass Plane (MJAM, σe, R^maj_e), showing that at fixed mass, compact early-type galaxies are on average older, more metal-rich, and more alpha-enhanced than their larger counterparts. From non-parametric star formation histories, we find that the duration of star formation is systematically more extended in lower mass objects. Assuming that our sample represents most of the stellar content of today's local Universe, approximately 50 per cent of all stars formed within the first 2 Gyr following the big bang. Most of these stars reside today in the most massive galaxies (>1010.5 M⊙), which themselves formed 90 per cent of their stars by z ˜ 2. The lower mass objects, in contrast, have formed barely half their stars in this time interval. Stellar population properties are independent of environment over two orders of magnitude in local density, varying only with galaxy mass. In the highest density regions of our volume (dominated by the Virgo cluster), galaxies are older, alpha-enhanced, and have shorter star formation histories with respect to lower density regions.

History of Higher Education: Curriculum.

ERIC Educational Resources Information Center

Harada, Myra

This paper reviews the history of undergraduate curriculum in the United States from the colonial period to the present, arguing that the drive for utility has been the main force shaping curricular trends. It discusses the purpose of early colonial colleges and their curricula, which emphasized Latin, Greek, Hebrew, ancient history, theology,…

A Structural History of English.

ERIC Educational Resources Information Center

Nist, John

This book combines a traditional history-of-the-language approach with modern linguistic analysis to discuss the history of English from Old English through Middle English, Early Modern English, Authoritarian English, Mature Modern English, to American English. The book begins with a discussion of the present status and structure of English. Each…

Variations in early life history traits of Japanese anchovy Engraulis japonicus in the Yangtze River Estuary.

PubMed

Liu, Chunlong; Xian, Weiwei; Liu, Shude; Chen, Yifeng

2018-01-01

Resources of Japanese anchovy ( Engraulis japonicus Temminck & Schlegel, 1846) are undergoing dramatic recessions in China as the consequence of intensifying anthropogenic activities. Elucidating the influences of local-scale environmental factors on early life history traits is of great importance to design strategies conserving and restoring the declining anchovy resources. In this research, we studied hatching date and early growth of anchovy in the Yangtze River Estuary (YRE) using information obtained from otolith microstructure. Onset of hatching season and growth rates of anchovy was compared to populations in Japan and Taiwan. In YRE, the hatching date of anchovy ranged from February 26th to April 6th and mean growth rate ranged from 0.27 to 0.77 mm/d. Anchovies hatching later had higher growth rates than individuals hatching earlier before the 25th day. Among populations, hatching onsets of anchovy from the higher latitude were later than populations in the lower latitude, and growth rates of anchovy in YRE were much lower than populations in Japan and Taiwan. Variations in hatching onsets and early growth patterns of anchovy thus provide important knowledge on understanding the adaptation of anchovy in YRE and designing management strategies on conserving China's anchovy resources.

Reproductive ecology and early life history traits of the brooding coral, Porites astreoides, from shallow to mesophotic zones

NASA Astrophysics Data System (ADS)

Goodbody-Gringley, Gretchen; Wong, Kevin H.; Becker, Danielle M.; Glennon, Keegan; de Putron, Samantha J.

2018-06-01

Early life history traits of brooding corals are often affected by the environmental conditions experienced by parental colonies. Such parental effects can impact offspring survival, which influences the overall success of a population as well as resilience to environmental challenges. This study examines the reproductive ecology and early life history traits of the brooding coral Porites astreoides across a depth gradient in Bermuda. Fecundity, larval size, larval Symbiodinium density, and settlement success, as well as post-metamorphic juvenile survival, growth, and Symbiodinium density were compared across three reef sites representing an inshore patch reef (2-5 m), an offshore rim reef (8-10 m), and an upper-mesophotic reef (30-33 m). Although fecundity did not differ across sites, larvae produced by colonies on the patch reef site were smaller, had lower Symbiodinium densities, and had lower rates of settlement and juvenile survival compared to larvae from colonies on the rim and upper-mesophotic reef sites. Larvae produced by colonies from the rim and upper-mesophotic sites did not differ in size or Symbiodinium densities; however, rates of settlement, growth, and survival were higher for larvae from the upper-mesophotic site compared to those from the rim reef site. These results indicate that offspring quality and success vary among sites with differing environmental conditions and may imply higher recruitment potential and resilience for upper-mesophotic corals.

Developmental trends of hot and cool executive function in school-aged children with and without autism spectrum disorder: Links with theory of mind.

PubMed

Kouklari, Evangelia-Chrysanthi; Tsermentseli, Stella; Monks, Claire P

2018-03-26

The development of executive function (EF) in autism spectrum disorder (ASD) has been investigated using only "cool"-cognitive EF tasks while there is limited knowledge regarding the development of "hot"-affective EF. Although cool EF development and its links to theory of mind (ToM) have been widely examined, understanding of the influence of hot EF to ToM mechanisms is minimal. The present study introduced a longitudinal design to examine the developmental changes in cool and hot EF of children with ASD (n = 45) and matched (to age and IQ) controls (n = 37) as well as the impact of EF on ToM development over a school year. For children with ASD, although selective cool (working memory and inhibition) and hot (affective decision making) EF domains presented age-related improvements, they never reached the performance level of the control group. Early cool working memory predicted later ToM in both groups but early hot delay discounting predicted later ToM only in the ASD group. No evidence was found for the reverse pattern (early ToM predicting later EF). These findings suggest that improvements in some EF aspects are evident in school age in ASD and highlight the crucial role that both cool and hot EF play in ToM development.

Passive cooling system for top entry liquid metal cooled nuclear reactors

DOEpatents

Boardman, Charles E.; Hunsbedt, Anstein; Hui, Marvin M.

1992-01-01

A liquid metal cooled nuclear fission reactor plant having a top entry loop joined satellite assembly with a passive auxiliary safety cooling system for removing residual heat resulting from fuel decay during shutdown, or heat produced during a mishap. This satellite type reactor plant is enhanced by a backup or secondary passive safety cooling system which augments the primary passive auxiliary cooling system when in operation, and replaces the primary cooling system when rendered inoperative.

An Ecological Analysis of the Effects of Deviant Peer Clustering on Sexual Promiscuity, Problem Behavior, and Childbearing from Early Adolescence to Adulthood: An Enhancement of the Life History Framework

PubMed Central

Dishion, Thomas J.; Ha, Thao; Véronneau, Marie-Hélène

2012-01-01

This study proposes the inclusion of peer relationships in a life history perspective on adolescent problem behavior. Longitudinal analyses were used to examine deviant peer clustering as the mediating link between attenuated family ties, peer marginalization, and social disadvantage in early adolescence and sexual promiscuity in middle adolescence and childbearing by early adulthood. Specifically, 998 youth and their families were assessed at age 11 years and periodically through age 24 years. Structural equation modeling revealed that the peer-enhanced life history model provided a good fit to the longitudinal data, with deviant peer clustering strongly predicting adolescent sexual promiscuity and other correlated problem behaviors. Sexual promiscuity, as expected, also strongly predicted the number of children by age 22–24 years. Consistent with a life history perspective, family social disadvantage directly predicted deviant peer clustering and number of children in early adulthood, controlling for all other variables in the model. These data suggest that deviant peer clustering is a core dimension of a fast life history strategy, with strong links to sexual activity and childbearing. The implications of these findings are discussed with respect to the need to integrate an evolutionary-based model of self-organized peer groups in developmental and intervention science. PMID:22409765

An ecological analysis of the effects of deviant peer clustering on sexual promiscuity, problem behavior, and childbearing from early adolescence to adulthood: an enhancement of the life history framework.

PubMed

Dishion, Thomas J; Ha, Thao; Véronneau, Marie-Hélène

2012-05-01

The authors propose that peer relationships should be included in a life history perspective on adolescent problem behavior. Longitudinal analyses were used to examine deviant peer clustering as the mediating link between attenuated family ties, peer marginalization, and social disadvantage in early adolescence and sexual promiscuity in middle adolescence and childbearing by early adulthood. Specifically, 998 youths, along with their families, were assessed at age 11 years and periodically through age 24 years. Structural equation modeling revealed that the peer-enhanced life history model provided a good fit to the longitudinal data, with deviant peer clustering strongly predicting adolescent sexual promiscuity and other correlated problem behaviors. Sexual promiscuity, as expected, also strongly predicted the number of children by ages 22-24 years. Consistent with a life history perspective, family social disadvantage directly predicted deviant peer clustering and number of children in early adulthood, controlling for all other variables in the model. These data suggest that deviant peer clustering is a core dimension of a fast life history strategy, with strong links to sexual activity and childbearing. The implications of these findings are discussed with respect to the need to integrate an evolutionary-based model of self-organized peer groups in developmental and intervention science.

Early fire history near Papineau lake, Ontario

Treesearch

Daniel C. Dey; Richard P. Guyette

1996-01-01

Research that defines the role of fire in upland red oak-pine ecosystems in central Ontario is being conducted by the Great Lakes-St. Lawrence Silviculture program. Site-specific fire histories are being developed that document fire frequency, fire behavior, fire effects on forest regeneration and grwoth, and the influnce of human activites on fire disturbances. This...

Ejector gas cooling. Phase 1. Final report, 1 April 1987-30 April 1988

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacCracken, C.D.; Silvetti, B.M.; Hrbek, R.

1988-11-01

Closed-circuit ejector cooling systems have never in the past achieved acceptable operating efficiencies in their vapor-compression cycle using standard refrigerants. Despite their long history, relative simplicity, quietness, rugged design, low maintenance and low cost, they could not compete with electric-motor-driven compressors. Phase I is an assessment of two immiscible fluids in an ejector cooling system with different latent heat capacity and molecular weights intended to require less heat in the boiler producing the propellant and taking more heat out in the evaporator cooling fluid. Actual tests corrected to standard conditions and neglecting thermal losses showed 0.5 closed-cycle thermal COP (excludingmore » stack losses), higher than ever previously achieved but below original expectations. Computer programs developed indicate higher COP values are attainable along with competitive first costs.« less

Personality over Policy: A Comparative History of the Founding and Early Development of Four Significant American Manuscript Repositories of Business, Industry, and Technology

ERIC Educational Resources Information Center

Nordberg, Erik C.

2017-01-01

This dissertation compares and contrasts the founding and early manuscript collecting activities of four publicly accessible American archival repositories known for their extensive holdings in business, industrial, and technological history: the Baker Library at Harvard University in Boston, Massachusetts; the Hagley Library and Museum in…

Film cooling air pocket in a closed loop cooled airfoil

DOEpatents

Yu, Yufeng Phillip; Itzel, Gary Michael; Osgood, Sarah Jane; Bagepalli, Radhakrishna; Webbon, Waylon Willard; Burdgick, Steven Sebastian

2002-01-01

Turbine stator vane segments have radially inner and outer walls with vanes extending between them. The inner and outer walls are compartmentalized and have impingement plates. Steam flowing into the outer wall plenum passes through the impingement plate for impingement cooling of the outer wall upper surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. To provide for air film cooing of select portions of the airfoil outer surface, at least one air pocket is defined on a wall of at least one of the cavities. Each air pocket is substantially closed with respect to the cooling medium in the cavity and cooling air pumped to the air pocket flows through outlet apertures in the wall of the airfoil to cool the same.

Closed circuit steam cooled turbine shroud and method for steam cooling turbine shroud

DOEpatents

Burdgick, Steven Sebastian; Sexton, Brendan Francis; Kellock, Iain Robertson

2002-01-01

A turbine shroud cooling cavity is partitioned to define a plurality of cooling chambers for sequentially receiving cooling steam and impingement cooling of the radially inner wall of the shoud. An impingement baffle is provided in each cooling chamber for receiving the cooling media from a cooling media inlet in the case of the first chamber or from the immediately upstream chamber in the case of the second through fourth chambers and includes a plurality of impingement holes for effecting the impingement cooling of the shroud inner wall.

Classroom Wall Charts and Biblical History: A Study of Educational Technology in Elementary Schools in Late Nineteenth- and Early Twentieth-Century Sweden

ERIC Educational Resources Information Center

Evertsson, Jakob

2014-01-01

This article considers the emergence of classroom wall charts as a teaching technology in Swedish elementary schools in the late nineteenth and early twentieth centuries, using Biblical history teaching as an example. There has been some work done internationally on wall charts as an instructional technology, but few studies have looked at their…

Internally heated mantle convection and the thermal and degassing history of the earth

NASA Technical Reports Server (NTRS)

Williams, David R.; Pan, Vivian

1992-01-01

An internally heated model of parameterized whole mantle convection with viscosity dependent on temperature and volatile content is examined. The model is run for 4l6 Gyr, and temperature, heat flow, degassing and regassing rates, stress, and viscosity are calculated. A nominal case is established which shows good agreement with accepted mantle values. The effects of changing various parameters are also tested. All cases show rapid cooling early in the planet's history and strong self-regulation of viscosity due to the temperature and volatile-content dependence. The effects of weakly stress-dependent viscosity are examined within the bounds of this model and are found to be small. Mantle water is typically outgassed rapidly to reach an equilibrium concentration on a time scale of less than 200 Myr for almost all models, the main exception being for models which start out with temperatures well below the melting temperature.

To cool, but not too cool: that is the question--immersion cooling for hyperthermia.

PubMed

Taylor, Nigel A S; Caldwell, Joanne N; Van den Heuvel, Anne M J; Patterson, Mark J

2008-11-01

Patient cooling time can impact upon the prognosis of heat illness. Although ice-cold-water immersion will rapidly extract heat, access to ice or cold water may be limited in hot climates. Indeed, some have concerns regarding the sudden cold-water immersion of hyperthermic individuals, whereas others believe that cutaneous vasoconstriction may reduce convective heat transfer from the core. It was hypothesized that warmer immersion temperatures, which induce less powerful vasoconstriction, may still facilitate rapid cooling in hyperthermic individuals. Eight males participated in three trials and were heated to an esophageal temperature of 39.5 degrees C by exercising in the heat (36 degrees C, 50% relative humidity) while wearing a water-perfusion garment (40 degrees C). Subjects were cooled using each of the following methods: air (20-22 degrees C), cold-water immersion (14 degrees C), and temperate-water immersion (26 degrees C). The time to reach an esophageal temperature of 37.5 degrees C averaged 22.81 min (air), 2.16 min (cold), and 2.91 min (temperate). Whereas each of the between-trial comparisons was statistically significant (P < 0.05), cooling in temperate water took only marginally longer than that in cold water, and one cannot imagine that the 45-s cooling time difference would have any meaningful physiological or clinical implications. It is assumed that this rapid heat loss was due to a less powerful peripheral vasoconstrictor response, with central heat being more rapidly transported to the skin surface for dissipation. Although the core-to-water thermal gradient was much smaller with temperate-water cooling, greater skin and deeper tissue blood flows would support a superior convective heat delivery. Thus, a sustained physiological mechanism (blood flow) appears to have countered a less powerful thermal gradient, resulting in clinically insignificant differences in heat extraction between the cold and temperate cooling trials.

Impact of smoking history on the outcomes of women with early-stage breast cancer: a secondary analysis of a randomized study.

PubMed

Abdel-Rahman, Omar; Cheung, Winson Y

2018-04-11

To assess the impact of smoking history on the outcomes of early-stage breast cancer patients treated with sequential anthracyclines-taxanes in a randomized study. This is a secondary analysis of patient-level data of 1242 breast cancer patients referred for adjuvant chemotherapy in the BCIRG005 clinical trial. Overall survival was assessed according to smoking history through Kaplan-Meier analysis. Univariate and multivariate Cox regression analyses of factors affecting overall and relapse-free survival were subsequently conducted. Factors that were evaluated included: age, performance status, number of chemotherapy cycles, T stage, lymph node ratio, estrogen receptor status, adjuvant radiotherapy and smoking history. Kaplan-Meier analysis of overall survival according to smoking status (ever smoker vs. never smoker) was conducted. There was a trend toward a better overall survival among never smokers compared to ever smokers; however, it was not statistically significant (P = 0.098). The following factors were associated with better overall survival in multivariate analysis: older age (P = 0.011), complete chemotherapy course (P = 0.002), lower T stage (P < 0.0001), lower lymph node ratio (P < 0.0001) and positive estrogen receptor status (P = 0.006). Otherwise, the following factors were associated with better relapse-free survival in multivariate analysis: older age (P = 0.001), never smoking status (P = 0.021), lower T stage (P = 0.028), lower lymph node ratio (P < 0.0001) and positive estrogen receptor status (P < 0.0001). Early-stage breast cancer patients with a positive smoking history experienced worse relapse-free survival compared to never smokers. Physicians managing breast cancer patients should prioritize discussion about the benefits of smoking cessation when counseling their patients.

Performance characteristic of hybrid cooling system based on cooling pad and evaporator

NASA Astrophysics Data System (ADS)

Yoon, J. I.; Son, C. H.; Choi, K. H.; Kim, Y. B.; Sung, Y. H.; Roh, S. J.; Kim, Y. M.; Seol, S. H.

2018-01-01

In South Korea, most of domestic animals such as pigs and chickens might die due to thermal diseases if they are exposed to the high temperature consistently. In order to save them from the heat wave, numerous efforts have been carried out: installing a shade net, adjusting time of feeding, spraying mist and setting up a circulation fan. However, these methods have not shown significant improvements. Thus, this study proposes a hybrid cooling system combining evaporative cooler and air-conditioner in order to resolve the conventional problems caused by the high temperature in the livestock industry. The problem of cooling systems using evaporative cooling pads is that they are not effective for eliminating huge heat load due to their limited capacity. And, temperature of the supplied air cannot be low enough compared to conventional air-conditioning systems. On the other hand, conventional air-conditioning systems require relatively expensive installation cost, and high operating cost compared to evaporative cooling system. The hybrid cooling system makes up for the lack of cooling capacity of the evaporative cooler by employing the conventional air-conditioner. Additionally, temperature of supplied air can be lowered enough. In the hybrid cooling system, induced air by a fan is cooled by the evaporation of water in the cooling pad, and it is cooled again by an evaporator in the air-conditioner. Therefore, the more economical operation is possible due to additionally obtained cooling capacity from the cooling pads. Major results of experimental analysis of hybrid cooling system are as follows. The compressor power consumption of the hybrid cooling system is about 23% lower, and its COP is 17% higher than that of the conventional air-conditioners. Regarding the condition of changing ambient temperature, the total power consumption decreased by about 5% as the ambient temperature changed from 28.7°C to 31.7°C. Cooling capacity and COP also presented about 3% and 1

Early Thermal History of Rhea: The Role of Serpentinization and Liquid State Convection

NASA Astrophysics Data System (ADS)

Czechowski, Leszek; Łosiak, Anna

2016-12-01

Early thermal history of Rhea is investigated. The role of the following parameters of the model is investigated: time of beginning of accretion, tini, duration of accretion, tac, viscosity of ice close to the melting point, η0, activation energy in the formula for viscosity, E, thermal conductivity of silicate component, ksil, ammonia content, XNH3, and energy of serpentinization, cserp. We found that tini and tac are crucial for evolution. All other parameters are also important, but no dramatic differences are found for realistic values. The process of differentiation is also investigated. It is found that liquid state convection could delay the differentiation for hundreds of My. The results are confronted with observational data from Cassini spacecraft. It is possible that differentiation is fully completed but the density of formed core is close to the mean density. If this interpretation is correct, then Rhea could have accreted any time before 3-4 My after formation of CAI.

Effect of thermal history on Mossbauer signature and hyperfine interaction parameters of copper ferrite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Modi, K. B., E-mail: kunalbmodi2003@yahoo.com; Raval, P. Y.; Dulera, S. V.

Two specimens of copper ferrite, CuFe{sub 2}O{sub 4}, have been synthesized by double sintering ceramic technique with different thermal history i.e. slow cooled and quenched. X-ray diffractometry has confirmed single phase fcc spinel structure for slow cooled sample while tetragonal distortion is present in quenched sample. Mossbauer spectral analysis for slow-cooled copper ferrite reveals super position of two Zeeman split sextets along with paramagnetic singlet in the centre position corresponds to delafossite (CuFeO{sub 2}) phase that is completely absent in quenched sample. The hyperfine interaction parameters are highly influenced by heat treatment employed.

Thermal and exhumation history of the central Rwenzori Mountains, Western Rift of the East African Rift System, Uganda

NASA Astrophysics Data System (ADS)

Bauer, F. U.; Glasmacher, U. A.; Ring, U.; Schumann, A.; Nagudi, B.

2010-10-01

The Rwenzori Mountains (Mtns) in west Uganda are the highest rift mountains on Earth and rise to more than 5,000 m. We apply low-temperature thermochronology (apatite fission-track (AFT) and apatite (U-Th-Sm)/He (AHe) analysis) for tracking the cooling history of the Rwenzori Mtns. Samples from the central and northern Rwenzoris reveal AFT ages between 195.0 (±8.4) Ma and 85.3 (±5.3) Ma, and AHe ages between 210.0 (±6.0) Ma to 24.9 (±0.5) Ma. Modelled time-temperature paths reflect a protracted cooling history with accelerated cooling in Permo-Triassic and Jurassic times, followed by a long period of constant and slow cooling, than succeeded by a renewed accelerated cooling in the Neogene. During the last 10 Ma, differentiated erosion and surface uplift affected the Rwenzori Mtns, with more pronounced uplift along the western flank. The final rock uplift of the Rwenzori Mtns that partly led to the formation of the recent topography must have been fast and in the near past (Pliocene to Pleistocene). Erosion could not compensate for the latest rock uplift, resulting in Oligocene to Miocene AHe ages.

Cool-flame Extinction During N-Alkane Droplet Combustion in Microgravity

NASA Technical Reports Server (NTRS)

Nayagam, Vedha; Dietrich, Daniel L.; Hicks, Michael C.; Williams, Forman A.

2014-01-01

Recent droplet combustion experiments onboard the International Space Station (ISS) have revealed that large n-alkane droplets can continue to burn quasi-steadily following radiative extinction in a low-temperature regime, characterized by negative-temperaturecoefficient (NTC) chemistry. In this study we report experimental observations of n-heptane, n-octane, and n-decane droplets of varying initial sizes burning in oxygen/nitrogen/carbon dioxide and oxygen/helium/nitrogen environments at 1.0, 0.7, and 0.5 atmospheric pressures. The oxygen concentration in these tests varied in the range of 14% to 25% by volume. Large n-alkane droplets exhibited quasi-steady low-temperature burning and extinction following radiative extinction of the visible flame while smaller droplets burned to completion or disruptively extinguished. A vapor-cloud formed in most cases slightly prior to or following the "cool flame" extinction. Results for droplet burning rates in both the hot-flame and cool-flame regimes as well as droplet extinction diameters at the end of each stage are presented. Time histories of radiant emission from the droplet captured using broadband radiometers are also presented. Remarkably the "cool flame" extinction diameters for all the three n-alkanes follow a trend reminiscent of the ignition delay times observed in previous studies. The similarities and differences among the n-alkanes during "cool flame" combustion are discussed using simplified theoretical models of the phenomenon

Cooling of Gas Turbines. 2; Effectiveness of Rim Cooling of Blades

NASA Technical Reports Server (NTRS)

Wolfenstein, Lincoln; Meyer, Gene L.; McCarthy, John S.

1945-01-01

An analysis of rim cooling, which cools the blade by condition alone, was conducted. Gas temperatures ranged from 1300 degrees to 1900 degrees F and rim temperatures from 0 degrees to 1000 degrees F below gas temperatures. Results show that gas temperature increases up to 200 degrees F are permissible provided that the blades are cooled by 400 degrees to 500 degrees F below the gas temperature. Relatively small amounts of blade cooling, at constant gas temperature, give large increases in blade life. Dependence of rim cooling on heat-transfer coefficient, blade dimensions, and thermal conductivity is determined by a single parameter.

How Should Clinicians Counsel a Woman with a Strong Family History of Early-Onset Alzheimer's Disease about Her Pregnancy?

PubMed

Mapes, Marianna V; O'Brien, Barbara M; King, Louise P

2017-07-01

Counseling patients regarding the benefits, harms, and dilemmas of genetic testing is one of the greatest ethical challenges facing reproductive medicine today. With or without test results, clinicians grapple with how to communicate potential genetic risks as patients weigh their reproductive options. Here, we consider a case of a woman with a strong family history of early-onset Alzheimer's disease (EOAD). She is early in her pregnancy and unsure about learning her own genetic status. We address the ethical ramifications of each of her options, which include genetic testing, genetic counseling, and termination versus continuation of the pregnancy. Our analysis foregrounds clinicians' role in helping to ensure autonomous decision making as the patient reflects on these clinical options in light of her goals and values. © 2017 American Medical Association. All Rights Reserved.

History of ``NANO''-Scale VERY EARLY Solid-State (and Liquid-State) Physics/Chemistry/Metallurgy/ Ceramics; Interstitial-Alloys Carbides/Nitrides/Borides/...Powders and Cermets, Rock Shocks, ...

NASA Astrophysics Data System (ADS)

Maiden, Colin; Siegel, Edward

History of ``NANO'': Siegel-Matsubara-Vest-Gregson[Mtls. Sci. and Eng. 8, 6, 323(`71); Physica Status Solidi (a)11,45(`72)] VERY EARLY carbides/nitrides/borides powders/cermets solid-state physics/chemistry/metallurgy/ ceramics FIRST-EVER EXPERIMENTAL NANO-physics/chemistry[1968 ->Physica Status Solidi (a)11,45(`72); and EARLY NANO-``physics''/NANO-``chemistry'' THEORY(after: Kubo(`62)-Matsubara(`60s-`70s)-Fulde (`65) [ref.: Sugano[Microcluster-Physics, Springer('82 `98)

Passive cooling safety system for liquid metal cooled nuclear reactors

DOEpatents

Hunsbedt, Anstein; Boardman, Charles E.; Hui, Marvin M.; Berglund, Robert C.

1991-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

Indirect passive cooling system for liquid metal cooled nuclear reactors

DOEpatents

Hunsbedt, Anstein; Boardman, Charles E.

1990-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

A Qualitative Application of the Belsky Model to Explore Early Care and Education Teachers' Mealtime History, Beliefs, and Interactions.

PubMed

Swindle, Taren M; Patterson, Zachary; Boden, Carrie J

Studies on factors associated with nutrition practices in early care and education settings often focus on sociodemographic and programmatic characteristics. This qualitative study adapted and applied Belsky's determinants of parenting model to inform a broader exploration of Early Care and Education Teachers (ECETs) practices. Qualitative cross-sectional study with ECETs. The researchers interviewed ECETs in their communities across a Southern state. Purposive sampling was employed to recruit ECETs (n = 28) from Head Start or state-funded centers serving low-income families. Developmental histories of ECETs regarding food and nutrition, beliefs about child nutrition, and teaching interactions related to food. Qualitative interviews were coded using a deductive content analysis approach. Three distinct interrelationships were observed across the themes. First, rules and routines regarding food and mealtime in the educators' childhood often aligned with educator beliefs and behaviors at meals in their classroom. Second, some ECETs described motivations to leave a healthy food legacy for children in their class. Finally, an experience of food insecurity appeared in narratives that also emphasized making sure children got enough through various strategies. The influence of ECET developmental histories and their related beliefs can be addressed through professional development and ongoing support. Future study should quantify model constructs in a larger sample and study their relationships over time. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Cooling of the North Atlantic by Saharan Dust

NASA Technical Reports Server (NTRS)

Lau, K. M.; Kim, K. M.

2007-01-01

Using aerosol optical depth, sea surface temperature, top-of-the-atmosphere solar radiation flux, and oceanic mixed-layer depth from diverse data sources that include NASA satellites, NCEP reanalysis, in situ observations, as well as long-term dust records from Barbados, we examine the possible relationships between Saharan dust and Atlantic sea surface temperature. Results show that the estimated anomalous cooling pattern of the Atlantic during June 2006 relative to June 2005 due to attenuation of surface solar radiation by Saharan dust remarkably resemble observations, accounting for approximately 30-40% of the observed change in sea surface temperature. Historical data analysis show that there is a robust negative correlation between atmospheric dust loading and Atlantic SST consistent with the notion that increased (decreased) Saharan dust is associated with cooling (warming) of the Atlantic during the early hurricane season (July- August-September).

Bayesian analysis of the astrobiological implications of life's early emergence on Earth.

PubMed

Spiegel, David S; Turner, Edwin L

2012-01-10

Life arose on Earth sometime in the first few hundred million years after the young planet had cooled to the point that it could support water-based organisms on its surface. The early emergence of life on Earth has been taken as evidence that the probability of abiogenesis is high, if starting from young Earth-like conditions. We revisit this argument quantitatively in a bayesian statistical framework. By constructing a simple model of the probability of abiogenesis, we calculate a bayesian estimate of its posterior probability, given the data that life emerged fairly early in Earth's history and that, billions of years later, curious creatures noted this fact and considered its implications. We find that, given only this very limited empirical information, the choice of bayesian prior for the abiogenesis probability parameter has a dominant influence on the computed posterior probability. Although terrestrial life's early emergence provides evidence that life might be abundant in the universe if early-Earth-like conditions are common, the evidence is inconclusive and indeed is consistent with an arbitrarily low intrinsic probability of abiogenesis for plausible uninformative priors. Finding a single case of life arising independently of our lineage (on Earth, elsewhere in the solar system, or on an extrasolar planet) would provide much stronger evidence that abiogenesis is not extremely rare in the universe.

Cooled-Spool Piston Compressor

NASA Technical Reports Server (NTRS)

Morris, Brian G.

1994-01-01

Proposed cooled-spool piston compressor driven by hydraulic power and features internal cooling of piston by flowing hydraulic fluid to limit temperature of compressed gas. Provides sufficient cooling for higher compression ratios or reactive gases. Unlike conventional piston compressors, all parts of compressed gas lie at all times within relatively short distance of cooled surface so that gas cooled more effectively.

Radial turbine cooling

NASA Technical Reports Server (NTRS)

Roelke, Richard J.

1992-01-01

The technology of high temperature cooled radial turbines is reviewed. Aerodynamic performance considerations are described. Heat transfer and structural analysis are addressed, and in doing so the following topics are covered: cooling considerations, hot side convection, coolant side convection, and rotor mechanical analysis. Cooled rotor concepts and fabrication are described, and the following are covered in this context: internally cooled rotor, hot isostatic pressure bonded rotor, laminated rotor, split blade rotor, and the NASA radial turbine program.

Cooling circuit for and method of cooling a gas turbine bucket

DOEpatents

Jacala, Ariel C. P.

2002-01-01

A closed internal cooling circuit for a gas turbine bucket includes axial supply and return passages in the dovetail of the bucket. A first radial outward supply passage provides cooling medium to and along a passageway adjacent the leading edge and then through serpentine arranged passageways within the airfoil to a chamber adjacent the airfoil tip. A second radial passage crosses over the radial return passage for supplying cooling medium to and along a pair of passageways along the trailing edge of the airfoil section. The last passageway of the serpentine passageways and the pair of passageways communicate one with the other in the chamber for returning spent cooling medium radially inwardly along divided return passageways to the return passage. In this manner, both the leading and trailing edges are cooled using the highest pressure, lowest temperature cooling medium.

What Does Dance History Have to Do with Dancing? Making College Dance History Usable for Dancers

ERIC Educational Resources Information Center

Kattner, Elizabeth

2016-01-01

This paper explores methods for bringing dance history directly into the studio. It shows how the movement components that have proven successful in introductory courses can be extended to in-depth studies of dance history with dancers who have formal training. Through the example of a research project on the early work of George Balanchine, it…

Comments on ionization cooling channels

DOE PAGES

Neuffer, David

2017-09-25

Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the linear ionization cooling theory developed previously. In this study, we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

Comments on ionization cooling channels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neuffer, David

Ionization cooling channels with a wide variety of characteristics and cooling properties are being developed. These channels can produce cooling performances that are largely consistent with the linear ionization cooling theory developed previously. In this study, we review ionization cooling theory, discuss its application to presently developing cooling channels, and discuss criteria for optimizing cooling.

Cooling of Compact Stars with Nucleon Superfluidity and Quark Superconductivity

NASA Astrophysics Data System (ADS)

Noda, Tsuneo; Hashimoto, Masa-aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka

We show a cooling scenario of compact stars to satisfy recent observations of compact stars. The central density of compact stars can exceed the nuclear density, and it is considered that many hadronic phases appear at such a density. It is discussed that neutron superfluidity (1S0 for lower density, and 3P2 for higher density) and proton superfluidity/superconductivity (1S0) appears in all compact stars. And some "Exotic" states are considered to appear in compact stars, such as meson condensation, hyperon mixing, deconfinement of quarks and quark colour superconductivity. These exotic states appear at the density region above the threshold densities of each state. We demonstrate the thermal evolution of isolated compact stars, adopting the effects of nucleon superfluidity and quark colour superconductivity. We assume large gap energy (Δ > 10 MeV) for colour superconducting quark phase, and include the effects of nucleon superfluidity with parametrised models. We simulate the cooling history of compact stars, and shows that the heavier star does not always cool faster than lighter one, which is determined by the parameters of neutron 3P2 superfluidity.

Cyclic stress analysis of an air-cooled turbine vane

NASA Technical Reports Server (NTRS)

Kaufman, A.; Gauntner, D. J.; Gauntner, J. W.

1975-01-01

The effects of gas pressure level, coolant temperature, and coolant flow rate on the stress-strain history and life of an air-cooled vane were analyzed using measured and calculated transient metal temperatures and a turbine blade stress analysis program. Predicted failure locations were compared to results from cyclic tests in a static cascade and engine. The results indicate that a high gas pressure was detrimental, a high coolant flow rate somewhat beneficial, and a low coolant temperature the most beneficial to vane life.

New Ar/Ar single grain mineral ages from Korean orogenic belts with implications for the Triassic cooling and exhumation history

NASA Astrophysics Data System (ADS)

de Jong, Koenraad; Ruffet, Gilles; Han, Seokyoung

2013-04-01

ductily deformed rocks in the mylonitised top of the Gyeonggi Massif yielded different 1? plateau ages: 242.8 ± 1.0 Ma and 240.3 ± 1.0 Ma for two chlorite-mica schists, and 219.7 ± 0.9 Ma for a garnet-bearing micaceous quartzite. Two amphibolites from Neoproterozoic orthogneiss in the Hongseong area yielded concordant 1? plateau ages of 228.1 ± 1.0 (biotite), 230.1 ± 1.0 (hornblende), and 229.8 ± 1.0 Ma (hornblende from a foliated garnet-bearing corona-textured amphibolite). 40Ar/39Ar laser-probe dating produced robust evidence that cooling and exhumation of once deeply buried rocks in different parts of Korea essentially occurred in middle to late Triassic time. The concordance of hornblende and mica ages in each of the target areas implies a rapid cooling, during at least part of the history, which seems not to have been coeval. This corroborates the observation that our Ar/Ar mineral ages are only a couple of million years younger than CHIME and SHRIMP U-Pb ages in accessory minerals, which are in the 230-255 Ma range in the uppermost Gyeonggi Massif and Imjingang Belt, and between 225-235 Ma in the Hongseong area. However, the much younger muscovite age from the mylonitic quartzite implies a prolonged recrystallization in the ductile shear zone in the uppermost Gyeonggi Massif. This is subject of ongoing research.

Cooling characteristics of air cooled radial turbine blades

NASA Astrophysics Data System (ADS)

Sato, T.; Takeishi, K.; Matsuura, M.; Miyauchi, J.

The cooling design and the cooling characteristics of air cooled radial turbine wheels, which are designed for use with the gas generator turbine for the 400 horse power truck gas turbine engine, are presented. A high temperature and high speed test was performed under aerodynamically similar conditions to that of the prototype engine in order to confirm the metal temperature of the newly developed integrated casting wheels constructed of the superalloys INCO 713C. The test results compared with the analytical value, which was established on the basis of the results of the heat transfer test and the water flow test, are discussed.

Cool Vest

NASA Technical Reports Server (NTRS)

1982-01-01

ILC, Dover Division's lightweight cooling garment, called Cool Vest was designed to eliminate the harmful effects of heat stress; increases tolerance time in hot environments by almost 300 percent. Made of urethane-coated nylon used in Apollo, it works to keep the body cool, circulating chilled water throughout the lining by means of a small battery-powered pump. A pocket houses the pump, battery and the coolant which can be ice or a frozen gel, a valve control allows temperature regulation. One version is self-contained and portable for unrestrained movement, another has an umbilical line attached to an external source of coolant, such as standard tap water, when extended mobility is not required. It is reported from customers that the Cool Vest pays for itself in increased productivity in very high temperatures.

Tough Adults, Frail Babies: An Analysis of Stress Sensitivity across Early Life-History Stages of Widely Introduced Marine Invertebrates

PubMed Central

Pineda, M. Carmen; McQuaid, Christopher D.; Turon, Xavier; López-Legentil, Susanna; Ordóñez, Víctor; Rius, Marc

2012-01-01

All ontogenetic stages of a life cycle are exposed to environmental conditions so that population persistence depends on the performance of both adults and offspring. Most studies analysing the influence of abiotic conditions on species performance have focussed on adults, while studies covering early life-history stages remain rare. We investigated the responses of early stages of two widely introduced ascidians, Styela plicata and Microcosmus squamiger, to different abiotic conditions. Stressors mimicked conditions in the habitats where both species can be found in their distributional ranges and responses were related to the selection potential of their populations by analysing their genetic diversity. Four developmental stages (egg fertilisation, larval development, settlement, metamorphosis) were studied after exposure to high temperature (30°C), low salinities (26 and 22‰) and high copper concentrations (25, 50 and 100 µg/L). Although most stressors effectively led to failure of complete development (fertilisation through metamorphosis), fertilisation and larval development were the most sensitive stages. All the studied stressors affected the development of both species, though responses differed with stage and stressor. S. plicata was overall more resistant to copper, and some stages of M. squamiger to low salinities. No relationship was found between parental genetic composition and responses to stressors. We conclude that successful development can be prevented at several life-history stages, and therefore, it is essential to consider multiple stages when assessing species' abilities to tolerate stress. Moreover, we found that early development of these species cannot be completed under conditions prevailing where adults live. These populations must therefore recruit from elsewhere or reproduce during temporal windows of more benign conditions. Alternatively, novel strategies or behaviours that increase overall reproductive success might be

Hybrid radiator cooling system

DOEpatents

France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

2016-03-15

A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

Assessment of visual perception in adolescents with a history of central coordination disorder in early life – 15-year follow-up study

PubMed Central

Kowalski, Ireneusz M.; Domagalska, Małgorzata; Szopa, Andrzej; Dwornik, Michał; Kujawa, Jolanta; Stępień, Agnieszka; Śliwiński, Zbigniew

2012-01-01

Introduction Central nervous system damage in early life results in both quantitative and qualitative abnormalities of psychomotor development. Late sequelae of these disturbances may include visual perception disorders which not only affect the ability to read and write but also generally influence the child's intellectual development. This study sought to determine whether a central coordination disorder (CCD) in early life treated according to Vojta's method with elements of the sensory integration (S-I) and neuro-developmental treatment (NDT)/Bobath approaches affects development of visual perception later in life. Material and methods The study involved 44 participants aged 15-16 years, including 19 diagnosed with moderate or severe CCD in the neonatal period, i.e. during the first 2-3 months of life, with diagnosed mild degree neonatal encephalopathy due to perinatal anoxia, and 25 healthy people without a history of developmental psychomotor disturbances in the neonatal period. The study tool was a visual perception IQ test comprising 96 graphic tasks. Results The study revealed equal proportions of participants (p < 0.05) defined as very skilled (94-96), skilled (91-94), aerage (71-91), poor (67-71), and very poor (0-67) in both groups. These results mean that adolescents with a history of CCD in the neonatal period did not differ with regard to the level of visual perception from their peers who had not demonstrated psychomotor development disorders in the neonatal period. Conclusions Early treatment of children with CCD affords a possibility of normalising their psychomotor development early enough to prevent consequences in the form of cognitive impairments in later life. PMID:23185199

Early Depositional History of the Eocene Izu-Bonin Mariana Arc, Western Pacific Ocean

NASA Astrophysics Data System (ADS)

Waldman, R.; Marsaglia, K. M.; Tepley, F. J., III

2015-12-01

Expedition 351 of the International Ocean Discovery Program cored an Eocene section at Site U1438 in the Philippine Sea that provides insight into the early history of the Izu-Bonin arc. Subduction here is hypothesized to have initiated spontaneously, leaving a characteristic depositional sequence of post-subduction-initiation localized extension and volcanism. We conducted detailed macroscopic and microscopic study of the cores of the lowermost 100m of volcaniclastic and sedimentary rocks (Unit IV) directly overlying subduction initiation igneous basement, to identify depositional facies and trends. We subdivided Unit IV into three subunits based on lithologic characteristics. Transitions between the subunits are relatively abrupt, occurring within the length of a single core. The lowermost subunit (IVA) consists of 4 meters of laminated pelagic claystone with thin beds of graded volcaniclastic siltstone, and fine-grained tuff laminae composed of plagioclase feldspar and green-brown amphibole. The middle subunit (IVB) comprises 51 meters of texturally variable, thick-bedded, coarse-grained gravity flow deposits. These are composed of volcaniclastic sandstone and conglomerate containing glassy and tachylitic volcanic grains as well as sedimentary lithic fragments, along with traces of shallow-water carbonate bioclasts. Subunit IVB sediments are poorer in feldspar than IVA and contain only trace amphibole. They show variable grain rounding and an upsection increase in vitric components. Tachylite grains range from sub-angular to well rounded throughout, and other volcanic grain types show upward increases in angularity and vesicularity. The abrupt transition from pelagic sediments in subunit IVA to shallow-water-sourced gravity flows in subunit IVB suggests a rapid emergence of shallow-water to subaerial volcanic center early in the arc's development. The upper part of subunit IVB also contains igneous intrusions, providing possible evidence for more proximal

Reconstructed ancestral enzymes suggest long-term cooling of Earth's photic zone since the Archean

NASA Astrophysics Data System (ADS)

Garcia, Amanda K.; Schopf, J. William; Yokobori, Shin-ichi; Akanuma, Satoshi; Yamagishi, Akihiko

2017-05-01

Paleotemperatures inferred from the isotopic compositions (δ18O and δ30Si) of marine cherts suggest that Earth’s oceans cooled from 70 ± 15 °C in the Archean to the present ˜15 °C. This interpretation, however, has been subject to question due to uncertainties regarding oceanic isotopic compositions, diagenetic or metamorphic resetting of the isotopic record, and depositional environments. Analyses of the thermostability of reconstructed ancestral enzymes provide an independent method by which to assess the temperature history inferred from the isotopic evidence. Although previous studies have demonstrated extreme thermostability in reconstructed archaeal and bacterial proteins compatible with a hot early Earth, taxa investigated may have inhabited local thermal environments that differed significantly from average surface conditions. We here present thermostability measurements of reconstructed ancestral enzymatically active nucleoside diphosphate kinases (NDKs) derived from light-requiring prokaryotic and eukaryotic phototrophs having widely separated fossil-based divergence ages. The ancestral environmental temperatures thereby determined for these photic-zone organisms--shown in modern taxa to correlate strongly with NDK thermostability--are inferred to reflect ancient surface-environment paleotemperatures. Our results suggest that Earth's surface temperature decreased over geological time from ˜65-80 °C in the Archean, a finding consistent both with previous isotope-based and protein reconstruction-based interpretations. Interdisciplinary studies such as those reported here integrating genomic, geologic, and paleontologic data hold promise for providing new insight into the coevolution of life and environment over Earth history.

Reconstructed ancestral enzymes suggest long-term cooling of Earth's photic zone since the Archean.

PubMed

Garcia, Amanda K; Schopf, J William; Yokobori, Shin-Ichi; Akanuma, Satoshi; Yamagishi, Akihiko

2017-05-02

Paleotemperatures inferred from the isotopic compositions (δ 18 O and δ 30 Si) of marine cherts suggest that Earth's oceans cooled from 70 ± 15 °C in the Archean to the present ∼15 °C. This interpretation, however, has been subject to question due to uncertainties regarding oceanic isotopic compositions, diagenetic or metamorphic resetting of the isotopic record, and depositional environments. Analyses of the thermostability of reconstructed ancestral enzymes provide an independent method by which to assess the temperature history inferred from the isotopic evidence. Although previous studies have demonstrated extreme thermostability in reconstructed archaeal and bacterial proteins compatible with a hot early Earth, taxa investigated may have inhabited local thermal environments that differed significantly from average surface conditions. We here present thermostability measurements of reconstructed ancestral enzymatically active nucleoside diphosphate kinases (NDKs) derived from light-requiring prokaryotic and eukaryotic phototrophs having widely separated fossil-based divergence ages. The ancestral environmental temperatures thereby determined for these photic-zone organisms--shown in modern taxa to correlate strongly with NDK thermostability--are inferred to reflect ancient surface-environment paleotemperatures. Our results suggest that Earth's surface temperature decreased over geological time from ∼65-80 °C in the Archean, a finding consistent both with previous isotope-based and protein reconstruction-based interpretations. Interdisciplinary studies such as those reported here integrating genomic, geologic, and paleontologic data hold promise for providing new insight into the coevolution of life and environment over Earth history.

Cooled Water Production System,

DTIC Science & Technology

The invention refers to the field of air conditioning and regards an apparatus for obtaining cooled water . The purpose of the invention is to develop...such a system for obtaining cooled water which would permit the maximum use of the cooling effect of the water -cooling tower.

The Exhumation of the Central Lhasa, Tibet: Evidence from the Low-temperature Thermochronology

NASA Astrophysics Data System (ADS)

Sun, G.; Xiumian, H.; Sinclair, H. D.; Stuart, F. M.

2017-12-01

The modern Tibetan Plateau has an average elevation of 4500 m above the sea level. But its early growth history still remains debate, despite its significance to the global climate system. In common, the early growth of the Tibetan Plateau has been attributed to the India-Asia collision in the early Paleocene. However, the structural reconstruction, Late Cretaceous sedimentation, and petrology studies, imply there would be a paleo-plateau or the high-elevation gain in the Lhasa terrane prior to the India-Asia collision. In order to examine this model, the zircon/apatite U-Th-He (ZHe and AHe) and apatite fission track (AFT) are employed to the mid-Cretaceous granites in Coqen area, central Lhasa. Eight samples from the plateau surface yield ZHe ages ranging from 88 to 54 Ma, while the AHe ages ranging from 70 to 45 Ma. Five samples from the above have been conducted the AFT analysis and yielded AFT ages ranging between 73 and 62 Ma, showing the similar age ranges with the corresponding AHe ages. Single-sample inverse thermal kinetic modeling reveal that these intrusive rocks have undergone the rapid cooling history since 85 Ma, after when, the relatively slow cooling process has been established at 45 Ma. Inverse thermal-kinetic modeling of these data, recorded in the context of the Late Cretaceous rapid cooling history, is best interpreted by the early plateau growth in the central Lhasa. In consideration of the substantial crustal thickening and shortening in the Lhasa terrane during the Cretaceous, this Late Cretaceous-Early Paleogene rapid cooling history reveal that the exhumation of the central Lhasa has initiated before the India-Asia collision. This scenario is consistent with a 30 Ma ( 90-60 Ma) sedimentation hiatus since the Late Cretaceous terrestrial conglomerate deposition in the central Lhasa terrane.

Cool Cities, Cool Planet (LBNL Science at the Theater)

ScienceCinema

Rosenfeld, Arthur; Pomerantz, Melvin; Levinson, Ronnen

2018-06-14

Science at the Theater: Berkeley Lab scientists discuss how cool roofs can cool your building, your city ... and our planet. Arthur Rosenfeld, Professor of Physics Emeritus at UC Berkeley, founded the Berkeley Lab Center for Building Science in 1974. He served on the California Energy Commission from 2000 to 2010 and is commonly referred to as California's godfather of energy efficiency. Melvin Pomerantz is a member of the Heat Island Group at Berkeley Lab. Trained as a physicist at UC Berkeley, he specializes in research on making cooler pavements and evaluating their effects. Ronnen Levinson is a staff scientist at Berkeley Lab and the acting leader of its Heat Island Group. He has developed cool roofing and paving materials and helped bring cool roof requirements into building energy efficiency standards.

Oral History as Educational Technology Research

ERIC Educational Resources Information Center

Butler, Rebecca P.

2008-01-01

Oral history is a significant type of historical research. Its use in retaining records of the early days of educational technology provides another way to look at the history of this field. The remembrances of its founders inform everyone today of, not only of what went on before, but also of how current and future technologies evolve. There are…

Solid-State Laser Cooling of Ytterbium-Doped Tungstate Crystals

DTIC Science & Technology

2001-01-01

namely the heavy metal fluoride glass ZBLAN and yttrium aluminum garnet . Favorable properties of the ytterbium-tungstates include exceptionally high...Optical refrigeration in Nd-doped yttrium aluminum garnet ,” Phys. Rev. Lett. 21, 1172 (1968). 2M.S. Chang, S.S. Elliott, T.K. Gustafson, C. Hu, and...idea gained experimental feasibility. Even with this tool, early failures to optically cool condensed media such as Nd3+ doped in yttrium aluminum

Tarp-Assisted Cooling as a Method of Whole-Body Cooling in Hyperthermic Individuals.

PubMed

Hosokawa, Yuri; Adams, William M; Belval, Luke N; Vandermark, Lesley W; Casa, Douglas J

2017-03-01

We investigated the efficacy of tarp-assisted cooling as a body cooling modality. Participants exercised on a motorized treadmill in hot conditions (ambient temperature 39.5°C [103.1°F], SD 3.1°C [5.58°F]; relative humidity 38.1% [SD 6.7%]) until they reached exercise-induced hyperthermia. After exercise, participants were cooled with either partial immersion using a tarp-assisted cooling method (water temperature 9.20°C [48.56°F], SD 2.81°C [5.06°F]) or passive cooling in a climatic chamber. There were no differences in exercise duration (mean difference=0.10 minutes; 95% CI -5.98 to 6.17 minutes or end exercise rectal temperature (mean difference=0.10°C [0.18°F]; 95% CI -0.05°C to 0.25°C [-0.09°F to 0.45°F] between tarp-assisted cooling (48.47 minutes [SD 8.27 minutes]; rectal temperature 39.73°C [103.51°F], SD 0.27°C [0.49°F]) and passive cooling (48.37 minutes [SD 7.10 minutes]; 39.63°C [103.33°F], SD 0.40°C [0.72°F]). Cooling time to rectal temperature 38.25°C (100.85°F) was significantly faster in tarp-assisted cooling (10.30 minutes [SD 1.33 minutes]) than passive cooling (42.78 [SD 5.87 minutes]). Cooling rates for tarp-assisted cooling and passive cooling were 0.17°C/min (0.31°F/min), SD 0.07°C/min (0.13°F/min) and 0.04°C/min (0.07°F/min), SD 0.01°C/min (0.02°F/min), respectively (mean difference=0.13°C [0.23°F]; 95% CI 0.09°C to 0.17°C [0.16°F to 0.31°F]. No sex differences were observed in tarp-assisted cooling rates (men 0.17°C/min [0.31°F/min], SD 0.07°C/min [0.13°F/min]; women 0.16°C/min [0.29°F/min], SD 0.07°C/min [0.13°F/min]; mean difference=0.02°C/min [0.04°F/min]; 95% CI -0.06°C/min to 0.10°C/min [-0.11°F/min to 0.18°F/min]). Women (0.04°C/min [0.07°F/min], SD 0.01°C/min [0.02°F/min]) had greater cooling rates than men (0.03°C/min [0.05°F/min], SD 0.01°C/min [0.02°F/min]) in passive cooling, with negligible clinical effect (mean difference=0.01°C/min [0.02°F/min]; 95% CI 0.001�

Cool Flame Quenching

NASA Technical Reports Server (NTRS)

Pearlman, Howard; Chapek, Richard

2001-01-01

Cool flame quenching distances are generally presumed to be larger than those associated with hot flames, because the quenching distance scales with the inverse of the flame propagation speed, and cool flame propagation speeds are often times slower than those associated with hot flames. To date, this presumption has never been put to a rigorous test, because unstirred, non-isothermal cool flame studies on Earth are complicated by natural convection. Moreover, the critical Peclet number (Pe) for quenching of cool flames has never been established and may not be the same as that associated with wall quenching due to conduction heat loss in hot flames, Pe approx. = 40-60. The objectives of this ground-based study are to: (1) better understand the role of conduction heat loss and species diffusion on cool flame quenching (i.e., Lewis number effects), (2) determine cool flame quenching distances (i.e, critical Peclet number, Pe) for different experimental parameters and vessel surface pretreatments, and (3) understand the mechanisms that govern the quenching distances in premixtures that support cool flames as well as hot flames induced by spark-ignition. Objective (3) poses a unique fire safety hazard if conditions exist where cool flame quenching distances are smaller than those associated with hot flames. For example, a significant, yet unexplored risk, can occur if a multi-stage ignition (a cool flame that transitions to a hot flame) occurs in a vessel size that is smaller than that associated with the hot quenching distance. To accomplish the above objectives, a variety of hydrocarbon-air mixtures will be tested in a static reactor at elevated temperature in the laboratory (1g). In addition, reactions with chemical induction times that are sufficiently short will be tested aboard NASA's KC-135 microgravity (mu-g) aircraft. The mu-g results will be compared to a numerical model that includes species diffusion, heat conduction, and a skeletal kinetic mechanism

Cool Girls, Inc.: Promoting the Positive Development of Urban Preadolescent and Early Adolescent Girls

ERIC Educational Resources Information Center

Kuperminc, Gabriel P.; Thomason, Jessica; DiMeo, Michelle; Broomfield-Massey, Kimberley

2011-01-01

The past two decades have seen a transformation in youth programming toward a comprehensive positive youth development (YD) framework. Cool Girls, Inc., a YD program, focuses on improving girls' life chances by promoting positive behaviors and attitudes in multiple domains. These include self-concept, academic orientation, future orientation, and…

Turbine blade cooling

DOEpatents

Staub, Fred Wolf; Willett, Fred Thomas

1999-07-20

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Turbine blade cooling

DOEpatents

Staub, Fred Wolf; Willett, Fred Thomas

2000-01-01

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number.

Turbine blade cooling

DOEpatents

Staub, F.W.; Willett, F.T.

1999-07-20

A turbine rotor blade comprises a shank portion, a tip portion and an airfoil. The airfoil has a pressure side wall and a suction side wall that are interconnected by a plurality of partition sidewalls, defining an internal cooling passageway within the airfoil. The internal cooling passageway includes at least one radial outflow passageway to direct a cooling medium flow from the shank portion towards the tip portion and at least one radial inflow passageway to direct a cooling medium flow from the tip portion towards the shank portion. A number of mixing ribs are disposed on the partition sidewalls within the radial outflow passageways so as to enhance the thermal mixing of the cooling medium flow, thereby producing improved heat transfer over a broad range of the Buoyancy number. 13 figs.

Bayesian analysis of the astrobiological implications of life’s early emergence on Earth

PubMed Central

Spiegel, David S.; Turner, Edwin L.

2012-01-01

Life arose on Earth sometime in the first few hundred million years after the young planet had cooled to the point that it could support water-based organisms on its surface. The early emergence of life on Earth has been taken as evidence that the probability of abiogenesis is high, if starting from young Earth-like conditions. We revisit this argument quantitatively in a Bayesian statistical framework. By constructing a simple model of the probability of abiogenesis, we calculate a Bayesian estimate of its posterior probability, given the data that life emerged fairly early in Earth’s history and that, billions of years later, curious creatures noted this fact and considered its implications. We find that, given only this very limited empirical information, the choice of Bayesian prior for the abiogenesis probability parameter has a dominant influence on the computed posterior probability. Although terrestrial life's early emergence provides evidence that life might be abundant in the universe if early-Earth-like conditions are common, the evidence is inconclusive and indeed is consistent with an arbitrarily low intrinsic probability of abiogenesis for plausible uninformative priors. Finding a single case of life arising independently of our lineage (on Earth, elsewhere in the solar system, or on an extrasolar planet) would provide much stronger evidence that abiogenesis is not extremely rare in the universe. PMID:22198766

Genome sequencing highlights the dynamic early history of dogs.

PubMed

Freedman, Adam H; Gronau, Ilan; Schweizer, Rena M; Ortega-Del Vecchyo, Diego; Han, Eunjung; Silva, Pedro M; Galaverni, Marco; Fan, Zhenxin; Marx, Peter; Lorente-Galdos, Belen; Beale, Holly; Ramirez, Oscar; Hormozdiari, Farhad; Alkan, Can; Vilà, Carles; Squire, Kevin; Geffen, Eli; Kusak, Josip; Boyko, Adam R; Parker, Heidi G; Lee, Clarence; Tadigotla, Vasisht; Wilton, Alan; Siepel, Adam; Bustamante, Carlos D; Harkins, Timothy T; Nelson, Stanley F; Ostrander, Elaine A; Marques-Bonet, Tomas; Wayne, Robert K; Novembre, John

2014-01-01

To identify genetic changes underlying dog domestication and reconstruct their early evolutionary history, we generated high-quality genome sequences from three gray wolves, one from each of the three putative centers of dog domestication, two basal dog lineages (Basenji and Dingo) and a golden jackal as an outgroup. Analysis of these sequences supports a demographic model in which dogs and wolves diverged through a dynamic process involving population bottlenecks in both lineages and post-divergence gene flow. In dogs, the domestication bottleneck involved at least a 16-fold reduction in population size, a much more severe bottleneck than estimated previously. A sharp bottleneck in wolves occurred soon after their divergence from dogs, implying that the pool of diversity from which dogs arose was substantially larger than represented by modern wolf populations. We narrow the plausible range for the date of initial dog domestication to an interval spanning 11-16 thousand years ago, predating the rise of agriculture. In light of this finding, we expand upon previous work regarding the increase in copy number of the amylase gene (AMY2B) in dogs, which is believed to have aided digestion of starch in agricultural refuse. We find standing variation for amylase copy number variation in wolves and little or no copy number increase in the Dingo and Husky lineages. In conjunction with the estimated timing of dog origins, these results provide additional support to archaeological finds, suggesting the earliest dogs arose alongside hunter-gathers rather than agriculturists. Regarding the geographic origin of dogs, we find that, surprisingly, none of the extant wolf lineages from putative domestication centers is more closely related to dogs, and, instead, the sampled wolves form a sister monophyletic clade. This result, in combination with dog-wolf admixture during the process of domestication, suggests that a re-evaluation of past hypotheses regarding dog origins is

Genome Sequencing Highlights the Dynamic Early History of Dogs

PubMed Central

Freedman, Adam H.; Gronau, Ilan; Schweizer, Rena M.; Ortega-Del Vecchyo, Diego; Han, Eunjung; Silva, Pedro M.; Galaverni, Marco; Fan, Zhenxin; Marx, Peter; Lorente-Galdos, Belen; Beale, Holly; Ramirez, Oscar; Hormozdiari, Farhad; Alkan, Can; Vilà, Carles; Squire, Kevin; Geffen, Eli; Kusak, Josip; Boyko, Adam R.; Parker, Heidi G.; Lee, Clarence; Tadigotla, Vasisht; Siepel, Adam; Bustamante, Carlos D.; Harkins, Timothy T.; Nelson, Stanley F.; Ostrander, Elaine A.; Marques-Bonet, Tomas; Wayne, Robert K.; Novembre, John

2014-01-01

To identify genetic changes underlying dog domestication and reconstruct their early evolutionary history, we generated high-quality genome sequences from three gray wolves, one from each of the three putative centers of dog domestication, two basal dog lineages (Basenji and Dingo) and a golden jackal as an outgroup. Analysis of these sequences supports a demographic model in which dogs and wolves diverged through a dynamic process involving population bottlenecks in both lineages and post-divergence gene flow. In dogs, the domestication bottleneck involved at least a 16-fold reduction in population size, a much more severe bottleneck than estimated previously. A sharp bottleneck in wolves occurred soon after their divergence from dogs, implying that the pool of diversity from which dogs arose was substantially larger than represented by modern wolf populations. We narrow the plausible range for the date of initial dog domestication to an interval spanning 11–16 thousand years ago, predating the rise of agriculture. In light of this finding, we expand upon previous work regarding the increase in copy number of the amylase gene (AMY2B) in dogs, which is believed to have aided digestion of starch in agricultural refuse. We find standing variation for amylase copy number variation in wolves and little or no copy number increase in the Dingo and Husky lineages. In conjunction with the estimated timing of dog origins, these results provide additional support to archaeological finds, suggesting the earliest dogs arose alongside hunter-gathers rather than agriculturists. Regarding the geographic origin of dogs, we find that, surprisingly, none of the extant wolf lineages from putative domestication centers is more closely related to dogs, and, instead, the sampled wolves form a sister monophyletic clade. This result, in combination with dog-wolf admixture during the process of domestication, suggests that a re-evaluation of past hypotheses regarding dog origins is

Electron Cooling and Isotropization during Magnetotail Current Sheet Thinning: Implications for Parallel Electric Fields

NASA Astrophysics Data System (ADS)

Lu, San; Artemyev, A. V.; Angelopoulos, V.

2017-11-01

Magnetotail current sheet thinning is a distinctive feature of substorm growth phase, during which magnetic energy is stored in the magnetospheric lobes. Investigation of charged particle dynamics in such thinning current sheets is believed to be important for understanding the substorm energy storage and the current sheet destabilization responsible for substorm expansion phase onset. We use Time History of Events and Macroscale Interactions during Substorms (THEMIS) B and C observations in 2008 and 2009 at 18 - 25 RE to show that during magnetotail current sheet thinning, the electron temperature decreases (cooling), and the parallel temperature decreases faster than the perpendicular temperature, leading to a decrease of the initially strong electron temperature anisotropy (isotropization). This isotropization cannot be explained by pure adiabatic cooling or by pitch angle scattering. We use test particle simulations to explore the mechanism responsible for the cooling and isotropization. We find that during the thinning, a fast decrease of a parallel electric field (directed toward the Earth) can speed up the electron parallel cooling, causing it to exceed the rate of perpendicular cooling, and thus lead to isotropization, consistent with observation. If the parallel electric field is too small or does not change fast enough, the electron parallel cooling is slower than the perpendicular cooling, so the parallel electron anisotropy grows, contrary to observation. The same isotropization can also be accomplished by an increasing parallel electric field directed toward the equatorial plane. Our study reveals the existence of a large-scale parallel electric field, which plays an important role in magnetotail particle dynamics during the current sheet thinning process.

Maternal abuse history and self-regulation difficulties in preadolescence

PubMed Central

Delker, Brianna C.; Noll, Laura K.; Kim, Hyoun K.; Fisher, Philip A.

2014-01-01

Although poor parenting is known to be closely linked to self-regulation difficulties in early childhood, comparatively little is understood about the role of other risk factors in the early caregiving environment (such as a parent’s own experiences of childhood abuse) in developmental pathways of self-regulation into adolescence. Using a longitudinal design, this study aimed to examine how a mother’s history of abuse in childhood relates to her offspring’s self-regulation difficulties in preadolescence. Maternal controlling parenting and exposure to intimate partner aggression in the child’s first 24–36 months were examined as important early social and environmental influences that may explain the proposed connection between maternal abuse history and preadolescent self-regulation. An ethnically diverse sample of mothers (N = 488) who were identified as at-risk for child maltreatment was recruited at the time of their children’s birth. Mothers and their children were assessed annually from the child’s birth through 36 months, and at age 9–11 years. Structural equation modeling and bootstrap tests of indirect effects were conducted to address the study aims. Findings indicated that maternal abuse history indirectly predicted their children’s self-regulation difficulties in preadolescence mainly through maternal controlling parenting in early childhood, but not through maternal exposure to aggression by an intimate partner. Maternal history of childhood abuse and maternal controlling parenting in her child’s early life may have long-term developmental implications for child self-regulation. PMID:25459984

Cooling water distribution system

DOEpatents

Orr, Richard

1994-01-01

A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

Astrobiology in Brazil: early history and perspectives

NASA Astrophysics Data System (ADS)

Rodrigues, Fabio; Galante, Douglas; Paulino-Lima, Ivan G.; Duarte, Rubens T. D.; Friaça, Amancio C. S.; Lage, Claudia; Janot-Pacheco, Eduardo; Teixeira, Ramachrisna; Horvath, Jorge E.

2012-10-01

This review reports the Brazilian history in astrobiology, as well as the first delineation of a vision of the future development of the field in the country, exploring its abundant biodiversity, highly capable human resources and state-of-the-art facilities, reflecting the last few years of stable governmental investments in science, technology and education, all conditions providing good perspectives on continued and steadily growing funding for astrobiology-related research. Brazil is growing steadily and fast in terms of its worldwide economic power, an effect being reflected in different areas of the Brazilian society, including industry, technology, education, social care and scientific production. In the field of astrobiology, the country has had some important landmarks, more intensely after the First Brazilian Workshop on Astrobiology in 2006. The history of astrobiology in Brazil, however, is not so recent and had its first occurrence in 1958. Since then, researchers carried out many individual initiatives across the country in astrobiology-related fields, resulting in an ever growing and expressive scientific production. The number of publications, including articles and theses, has particularly increased in the last decade, but still counting with the effort of researchers working individually. That scenario started to change in 2009, when a formal group of Brazilian researchers working with astrobiology was organized, aiming at congregating the scientific community interested in the subject and to promote the necessary interactions to achieve a multidisciplinary work, receiving facilities and funding from the University de Sao Paulo and other funding agencies.

Cooling of Gas Turbines. 2; Effectiveness of Rim Cooling of Blades

NASA Technical Reports Server (NTRS)

Wolfenstein, Lincoln; Meyer, Gene L.; McCarthy, John S.

1947-01-01

An analysis is presented of rim cooling of gas-turbine blades; that is, reducing the temperature at the base of the blade (wheel rim), which cools the blade by conduction alone. Formulas for temperature and stress distributions along the blade are derived and, by the use of experimental stress-rupture data for a typical blade alloy, a relation is established between blade life (time for rupture), operating speed, and amount of rim cooling for several gas temperatures. The effect of blade parameter combining the effects of blade dimensions, blade thermal conductivity, and heat-transfer coefficient is determined. The effect of radiation on the results is approximated. The gas temperatures ranged from 1300F to 1900F and the rim temperature, from 0F to 1000F below the gas temperature. This report is concerned only with blades of uniform cross section, but the conclusions drawn are generally applicable to most modern turbine blades. For a typical rim-cooled blade, gas temperature increases are limited to about 200F for 500F of cooling of the blade base below gas temperature, and additional cooling brings progressively smaller increases. In order to obtain large increases in thermal conductivity or very large decreases in heat-transfer coefficient or blade length or necessary. The increases in gas temperature allowable with rim cooling are particularly small for turbines of large dimensions and high specific mass flows. For a given effective gas temperature, substantial increases in blade life, however, are possible with relatively small amounts of rim cooling.

Omotic Peoples and the Early History of Agriculture in Southern Ethiopia

ERIC Educational Resources Information Center

Assefa, Shiferaw Alemu

2011-01-01

The primary objective of this dissertation is to reconstruct the history of the Omotic societies of southwestern Ethiopia. Although historical, anthropological, and linguistic studies exist for this region, the gaps in our knowledge are great. Information on the history of Omotic people, their economic and political systems, beliefs and values,…

Reading skills in young adolescents with a history of Specific Language Impairment: The role of early semantic capacity.

PubMed

Buil-Legaz, Lucía; Aguilar-Mediavilla, Eva; Rodríguez-Ferreiro, Javier

2015-01-01

This study assessed the reading skills of 19 Spanish-Catalan children with Specific Language Impairment (SLI) and 16 age-matched control children. Children with SLI have difficulties with oral language comprehension, which may affect later reading acquisition. We conducted a longitudinal study examining reading acquisition in these children between 8 and 12 years old and we relate this data with early oral language acquisition at 6 years old. Compared to the control group, the SLI group presented impaired decoding and comprehension skills at age 8, as evidenced by poor scores in all the assessed tasks. Nevertheless, only text comprehension abilities appeared to be impaired at age 12. Individual analyses confirmed the presence of comprehension deficits in most of the SLI children. Furthermore, early semantic verbal fluency at age 6 appeared to significantly predict the reading comprehension capacity of SLI participants at age 12. Our results emphasize the importance of semantic capacity at early stages of oral language development over the consolidation of reading acquisition at later stages. Readers will recognize the relevance of prior oral language impairment, especially semantic capacity, in children with a history of SLI as a risk factor for the development of later reading difficulties. Copyright © 2015 Elsevier Inc. All rights reserved.

Prader-Willi syndrome and early-onset morbid obesity NIH rare disease consortium: A review of natural history study.

PubMed

Butler, Merlin G; Kimonis, Virginia; Dykens, Elisabeth; Gold, June A; Miller, Jennifer; Tamura, Roy; Driscoll, Daniel J

2018-02-01

We describe the National Institutes of Health rare disease consortium for Prader-Willi syndrome (PWS) developed to address concerns regarding medical care, diagnosis, growth and development, awareness, and natural history. PWS results from errors in genomic imprinting leading to loss of paternally expressed genes due to 15q11-q13 deletion, maternal disomy 15 or imprinting defects. The 8 year study was conducted at four national sites on individuals with genetically confirmed PWS and early-onset morbid obesity (EMO) with data accumulated to gain a better understanding of the natural history, cause and treatment of PWS. Enrollment of 355 subjects with PWS and 36 subjects with EMO began in September 2006 with study completion in July 2014. Clinical, genetic, cognitive, behavior, and natural history data were systematically collected along with PWS genetic subtypes, pregnancy and birth history, mortality, obesity, and cognitive status with study details as important endpoints in both subject groups. Of the 355 individuals with PWS, 217 (61%) had the 15q11-q13 deletion, 127 (36%) had maternal disomy 15, and 11 (3%) had imprinting defects. Six deaths were reported in our PWS cohort with 598 cumulative years of study exposure and one death in the EMO group with 42 years of exposure. To our knowledge, this description of a longitudinal study in PWS represents the largest and most comprehensive cohort useful for investigators in planning comparable studies in other rare disorders. Ongoing studies utilizing this database should have a direct impact on care and services, diagnosis, treatment, genotype-phenotype correlations, and clinical outcomes in PWS. © 2017 Wiley Periodicals, Inc.

Thermal and impact histories of reheated group IVA, IVB, and ungrouped iron meteorites and their parent asteroids

NASA Astrophysics Data System (ADS)

Yang, J.; Goldstein, J. I.; Scott, E. R. D.; Michael, J. R.; Kotula, P. G.; Pham, T.; McCoy, T. J.

2011-09-01

cause of reheating. Cooling over years rather than hours precludes shock during the impacts that exposed the irons to cosmic rays. If the reheated irons that we studied are representative, the IVA irons may have been shocked soon after they cooled below 200 °C at 4.5 Gyr in an impact that created a rubblepile asteroid with fragments from diverse depths. The primary cooling rates of the IVA irons and the proposed early history are remarkably consistent with the Pb-Pb ages of troilite inclusions in two IVA irons including the oldest known differentiated meteorite (Blichert-Toft et al. 2010).

Turbomachine rotor with improved cooling

DOEpatents

Hultgren, Kent Goran; McLaurin, Leroy Dixon; Bertsch, Oran Leroy; Lowe, Perry Eugene

1998-01-01

A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn.

Using data to attribute episodes of warming and cooling in instrumental records.

PubMed

Tung, Ka-Kit; Zhou, Jiansong

2013-02-05

The observed global-warming rate has been nonuniform, and the cause of each episode of slowing in the expected warming rate is the subject of intense debate. To explain this, nonrecurrent events have commonly been invoked for each episode separately. After reviewing evidence in both the latest global data (HadCRUT4) and the longest instrumental record, Central England Temperature, a revised picture is emerging that gives a consistent attribution for each multidecadal episode of warming and cooling in recent history, and suggests that the anthropogenic global warming trends might have been overestimated by a factor of two in the second half of the 20th century. A recurrent multidecadal oscillation is found to extend to the preindustrial era in the 353-y Central England Temperature and is likely an internal variability related to the Atlantic Multidecadal Oscillation (AMO), possibly caused by the thermohaline circulation variability. The perspective of a long record helps in quantifying the contribution from internal variability, especially one with a period so long that it is often confused with secular trends in shorter records. Solar contribution is found to be minimal for the second half of the 20th century and less than 10% for the first half. The underlying net anthropogenic warming rate in the industrial era is found to have been steady since 1910 at 0.07-0.08 °C/decade, with superimposed AMO-related ups and downs that included the early 20th century warming, the cooling of the 1960s and 1970s, the accelerated warming of the 1980s and 1990s, and the recent slowing of the warming rates. Quantitatively, the recurrent multidecadal internal variability, often underestimated in attribution studies, accounts for 40% of the observed recent 50-y warming trend.

Using data to attribute episodes of warming and cooling in instrumental records

PubMed Central

Tung, Ka-Kit; Zhou, Jiansong

2013-01-01

The observed global-warming rate has been nonuniform, and the cause of each episode of slowing in the expected warming rate is the subject of intense debate. To explain this, nonrecurrent events have commonly been invoked for each episode separately. After reviewing evidence in both the latest global data (HadCRUT4) and the longest instrumental record, Central England Temperature, a revised picture is emerging that gives a consistent attribution for each multidecadal episode of warming and cooling in recent history, and suggests that the anthropogenic global warming trends might have been overestimated by a factor of two in the second half of the 20th century. A recurrent multidecadal oscillation is found to extend to the preindustrial era in the 353-y Central England Temperature and is likely an internal variability related to the Atlantic Multidecadal Oscillation (AMO), possibly caused by the thermohaline circulation variability. The perspective of a long record helps in quantifying the contribution from internal variability, especially one with a period so long that it is often confused with secular trends in shorter records. Solar contribution is found to be minimal for the second half of the 20th century and less than 10% for the first half. The underlying net anthropogenic warming rate in the industrial era is found to have been steady since 1910 at 0.07–0.08 °C/decade, with superimposed AMO-related ups and downs that included the early 20th century warming, the cooling of the 1960s and 1970s, the accelerated warming of the 1980s and 1990s, and the recent slowing of the warming rates. Quantitatively, the recurrent multidecadal internal variability, often underestimated in attribution studies, accounts for 40% of the observed recent 50-y warming trend. PMID:23345448

A Life History Assessment of Early Childhood Sexual Abuse in Women

ERIC Educational Resources Information Center

Vigil, Jacob M.; Geary, David C.; Byrd-Craven, Jennifer

2005-01-01

Life history theory provided a framework for examining the relations among child sexual abuse (CSA), childhood adversity, and patterns of reproductive development and behavior. A community survey that assessed CSA, life history variables (e.g., age of menarche), and social and family background was administered to 623 women (mean age=26.9 years).…

History of the National Weather Service - Public Affairs - NOAA's National

Science.gov Websites

enter or select the go button to submit request City, St Go About NWS -Mission -Strategic Plan -History and local government web resources and services. Home >> History History of the National Weather Service The National Weather Service has its beginnings in the early history of the United States. Weather

Determination of heat transfer coefficient for an interaction of sub-cooled gas and metal

NASA Astrophysics Data System (ADS)

Zaidi Sidek, Mohd; Syahidan Kamarudin, Muhammad

2016-02-01

Heat transfer coefficient (HTC) for a hot metal surface and their surrounding is one of the need be defined parameter in hot forming process. This study has been conducted to determine the HTC for an interaction between sub-cooled gas sprayed on a hot metal surface. Both experiments and finite element have been adopted in this work. Initially, the designated experiment was conducted to obtain temperature history of spray cooling process. Then, an inverse method was adopted to calculate the HTC value before we validate in a finite element simulation model. The result shows that the heat transfer coefficient for interaction of subcooled gas and hot metal surface is 1000 W/m2K.

Gas turbine cooling system

DOEpatents

Bancalari, Eduardo E.

2001-01-01

A gas turbine engine (10) having a closed-loop cooling circuit (39) for transferring heat from the hot turbine section (16) to the compressed air (24) produced by the compressor section (12). The closed-loop cooling system (39) includes a heat exchanger (40) disposed in the flow path of the compressed air (24) between the outlet of the compressor section (12) and the inlet of the combustor (14). A cooling fluid (50) may be driven by a pump (52) located outside of the engine casing (53) or a pump (54) mounted on the rotor shaft (17). The cooling circuit (39) may include an orifice (60) for causing the cooling fluid (50) to change from a liquid state to a gaseous state, thereby increasing the heat transfer capacity of the cooling circuit (39).

Curved film cooling admission tube

NASA Astrophysics Data System (ADS)

Graham, R. W.; Papell, S. S.

1980-10-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Curved film cooling admission tube

NASA Technical Reports Server (NTRS)

Graham, R. W.; Papell, S. S. (Inventor)

1980-01-01

Effective film cooling to protect a wall surface from a hot fluid which impinges on or flows along the surface is provided. A film of cooling fluid having increased area is provided by changing the direction of a stream of cooling fluid through an angle of from 135 deg. to 165 deg. before injecting it through the wall into the hot flowing gas. The 1, cooling fluid is injected from an orifice through a wall into a hot flowing gas at an angle to form a cooling fluid film. Cooling fluid is supplied to the orifice from a cooling fluid source via a turbulence control passageway having a curved portion between two straight portions. The angle through which the direction of the cooling fluid is turned results in less mixing of the cooling fluid with the hot gas, thereby substantially increasing the length of the film in a downstream direction.

Turbomachine rotor with improved cooling

DOEpatents

Hultgren, K.G.; McLaurin, L.D.; Bertsch, O.L.; Lowe, P.E.

1998-05-26

A gas turbine rotor has an essentially closed loop cooling air scheme in which cooling air drawn from the compressor discharge air that is supplied to the combustion chamber is further compressed, cooled, and then directed to the aft end of the turbine rotor. Downstream seal rings attached to the downstream face of each rotor disc direct the cooling air over the downstream disc face, thereby cooling it, and then to cooling air passages formed in the rotating blades. Upstream seal rings attached to the upstream face of each disc direct the heated cooling air away from the blade root while keeping the disc thermally isolated from the heated cooling air. From each upstream seal ring, the heated cooling air flows through passages in the upstream discs and is then combined and returned to the combustion chamber from which it was drawn. 5 figs.

Effect of thermal history on mechanical properties of polyetheretherketone below the glass transition temperature

NASA Technical Reports Server (NTRS)

Cebe, Peggy; Chung, Shirley Y.; Hong, Su-Don

1987-01-01

The effect of thermal history on the tensile properties of polyetheretherketone neat resin films was investigated at different test temperatures (125, 25, and -100) using four samples: fast-quenched amorphous (Q); quenched, then crystallized at 180 C (C180); slowly cooled (for about 16 h) from the melt (SC); and air-cooled (2-3 h) from the melt (AC). It was found that thermal history significantly affects the tensile properties of the material below the glass transition. Fast quenched amorphous films were most tough, could be drawn to greatest strain before rupture, and undergo densification during necking; at the test temperature of -100 C, these films had the best ultimate mechanical properties. At higher temperatures, the semicrystalline films AC and C180 had properties that compared favorably with the Q films. The SC films exhibited poor mechanical properties at all test temperatures.

Exhumation History Of Brasilian Highlands After Late Cretaceous Alcaline Magmatism

NASA Astrophysics Data System (ADS)

Doranti Tiritan, Carolina; Hackspacher, Peter Christian; Carina Siqueira Ribeiro, Marli; Glasmacher, Ulrich Anton; Françoso de Godoy, Daniel

2017-04-01

The southeast Brazilian margin recorded a long history of tectonic and magmatic events after the Gondwana continent break up. The drifting of the South American Platform over a thermal anomaly generated a series of alkaline intrusions that are distributed from the interior to the coast from west to east. Several exhumation events are recorded on the region and we are providing insights on the landscape evolution of the region since Late Cretaceous, comparing low temperature thermochronology results from two alkaline intrusions regions. Poços de Caldas Alkaline Massif (PCAM), is lied in the interior, 300km from the coastline, covering over 800km2 intruding the Precambrian basement around 83Ma, nepheline syenites, phonolites and tinguaites intruded in a continuous and rapid sequence lasting between 1 to 2 Ma. São Sebastião Island (SSI) on the other hand is located at the coast, 200 km southeast of São Paulo. It is characterized by an intrusion in Precambrian/Brazilian orogen and intruded by Early Cretaceous sub-alkaline basic and acid dykes, as well as by Late Cretaceous alkaline stocks (syenites) and dykes (basanite to phonolite). Will be presenting the apatite fission track (AFT) and (U-Th)/He results that shows the main difference between the areas is that PCAM region register older history then the coastal area of SSI, where thermal history starts register cooling event after the South Atlantic rifting process, while in the PCAM area register a previous history, since Carboniferous. The results are giving support to studies that indicate the development of the relief in Brazil being strongly influenced by the local and regional tectonic movements and the lithological and structural settings. The landscape at the Late Cretaceous was witness of heating process between 90 and 60Ma due the intense uplift of South American Platform. The elevation of the isotherms is associated with the mantellic plumes and the crustal thickness that caused thermal anomalies due

Cool Shelter

ERIC Educational Resources Information Center

Praeger, Charles E.

2005-01-01

Amid climbing energy costs and tightening budgets, administrators at school districts, colleges and universities are looking for all avenues of potential savings while promoting sustainable communities. Cool metal roofing can save schools money and promote sustainable design at the same time. Cool metal roofing keeps the sun's heat from collecting…

Fifty years of IAA History Symposia (1967-2016)

NASA Astrophysics Data System (ADS)

Skoog, A. Ingemar; Hall, R. Cargill

2017-05-01

The International Academy of Astronautics (IAA) Symposia on the History of Rocketry and Astronautics have been held annually at the International Astronautical Congresses since 1967. During these past 50 years nearly 800 papers have been presented and subsequently published in the proceedings. With a 20-year rule imposed for historical presentations, the first 10 symposia concentrated on pre-World War II and early 1950s activities. A surprisingly large number of papers on early, less well-known Soviet-Russian contributions to rocketry and astronautics were presented in the first symposia, despite the ongoing Space Race between the U.S and USSR. Another important element in these symposia involved memoir papers offered by pre- and post-war rocket and astronautics pioneers from many countries, and the participation of many of these pioneers in person. In sum, the history of national space and rocket projects from some 40 countries were presented over the years in IAA History Symposia. These 50 symposia have provided a platform for scholars and professional and non-professional historians to meet and discuss the history of rocketry and astronautics, and to personally interview many space pioneers, most of whom today are deceased. Their personal recollections have since been shared with a large audience. Over time, IAA history papers divided into recognizable periods: ancient times through the 19th century, and the 20th and 21st centuries, which separate among actions and events that took place before 1945, in 1945 to 1957, and after 1957 (which marked the beginning of the space age). Proceedings of the IAA History Symposia have been published in English, ultimately in the History Series of the American Astronautical Society (AAS) and its publishing arm, Univelt Inc., under an agreement secured with the IAA. This paper presents an overview of the IAA History Symposia. It examines the early years of the history committee and its first symposium, the evolution of

Renewable Heating and Cooling

EPA Pesticide Factsheets

Find information on the benefits of renewable heating and cooling technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

Superfluid 3He—the Early Days

NASA Astrophysics Data System (ADS)

Lee, D. M.; Leggett, A. J.

2011-08-01

A history is given of liquid 3He research from the time when 3He first became available following World War II through 1972 when the discovery of the superfluid phases was made. The Fermi liquid nature was established early on, and the Landau Fermi liquid theory provided a framework for understanding the interactions between the Fermions (quasiparticles). The theory's main triumph was to predict zero sound, which was soon discovered experimentally. Experimental techniques are treated, including adiabatic demagnetization, dilution refrigerator technology, and Pomeranchuk cooling. A description of the superfluid 3He discovery experiments using the latter two of these techniques is given. While existing theories provided a basis for understanding the newly discovered superfluid phases in terms of ℓ>0 Cooper pairs, the unexpected stability of the A phase in the high- P, high- T region of the phase diagram needed for its explanation a creative leap beyond the BCS paradigm. The use of sum rules to interpret some of the unusual magnetic resonance in liquid 3He is discussed. Eventually a complete theory of the spin dynamics of superfluid 3He was developed, which predicted many of the exciting phenomena subsequently discovered.

Cooling of gas turbines IX : cooling effects from use of ceramic coatings on water-cooled turbine blades

NASA Technical Reports Server (NTRS)

Brown, W Byron; Livingood, John N B

1948-01-01

The hottest part of a turbine blade is likely to be the trailing portion. When the blades are cooled and when water is used as the coolant, the cooling passages are placed as close as possible to the trailing edge in order to cool this portion. In some cases, however, the trailing portion of the blade is so narrow, for aerodynamic reasons, that water passages cannot be located very near the trailing edge. Because ceramic coatings offer the possibility of protection for the trailing part of such narrow blades, a theoretical study has been made of the cooling effect of a ceramic coating on: (1) the blade-metal temperature when the gas temperature is unchanged, and (2) the gas temperature when the metal temperature is unchanged. Comparison is also made between the changes in the blade or gas temperatures produced by ceramic coatings and the changes produced by moving the cooling passages nearer the trailing edge. This comparison was made to provide a standard for evaluating the gains obtainable with ceramic coatings as compared to those obtainable by constructing the turbine blade in such a manner that water passages could be located very near the trailing edge.

Renewable Heating And Cooling

EPA Pesticide Factsheets

Renewable heating and cooling is a set of alternative resources and technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

Non-intrusive cooling system

DOEpatents

Morrison, Edward F.; Bergman, John W.

2001-05-22

A readily replaceable heat exchange cooling jacket for applying fluid to a system conduit pipe. The cooling jacket comprises at least two members, separable into upper and lower portions. A chamber is formed between the conduit pipe and cooling jacket once the members are positioned about the pipe. The upper portion includes a fluid spray means positioned above the pipe and the bottom portion includes a fluid removal means. The heat exchange cooling jacket is adaptable with a drain tank, a heat exchanger, a pump and other standard equipment to provide a system for removing heat from a pipe. A method to remove heat from a pipe, includes the steps of enclosing a portion of the pipe with a jacket to form a chamber between an outside surface of the pipe and the cooling jacket; spraying cooling fluid at low pressure from an upper portion of the cooling jacket, allowing the fluid to flow downwardly by gravity along the surface of the pipe toward a bottom portion of the chamber; and removing the fluid at the bottom portion of the chamber.

Oral history of Florence Downs; the early years.

PubMed

Fairman, J; Mahon, M M

2001-01-01

Florence Downs is a well-recognized nursing leader, educator, editor, and scholar who helped shape nursing as an intellectual discipline, and wrote extensively about the importance of links between research and practice. Through the use of oral history data garnered over 15 hours of interviews, we constructed a narrative that describes some of Downs' formative experiences. Oral history is used to place the "stories" of an individual into a social and cultural context, in this case, the development of the profession of nursing. From the interviews, several strands emerged that defined Downs' extended career, including the importance of developing a community of scholars both in and outside of nursing, the dangers of parochialism, and the necessity of a perspective on life that melded a keen sense of humor. Factors that affected Downs' style and choice, especially her mother, and her educational experiences, were revealed. From the interviews we gained a sense of how Downs constructed her conceptual universe of nursing, as well as the language and political effectiveness to overcome barriers confronting the intellectual growth of nursing mounted by other nursing leaders as well as traditional academic disciplines.

Cooling Performance Analysis of ThePrimary Cooling System ReactorTRIGA-2000Bandung

NASA Astrophysics Data System (ADS)

Irianto, I. D.; Dibyo, S.; Bakhri, S.; Sunaryo, G. R.

2018-02-01

The conversion of reactor fuel type will affect the heat transfer process resulting from the reactor core to the cooling system. This conversion resulted in changes to the cooling system performance and parameters of operation and design of key components of the reactor coolant system, especially the primary cooling system. The calculation of the operating parameters of the primary cooling system of the reactor TRIGA 2000 Bandung is done using ChemCad Package 6.1.4. The calculation of the operating parameters of the cooling system is based on mass and energy balance in each coolant flow path and unit components. Output calculation is the temperature, pressure and flow rate of the coolant used in the cooling process. The results of a simulation of the performance of the primary cooling system indicate that if the primary cooling system operates with a single pump or coolant mass flow rate of 60 kg/s, it will obtain the reactor inlet and outlet temperature respectively 32.2 °C and 40.2 °C. But if it operates with two pumps with a capacity of 75% or coolant mass flow rate of 90 kg/s, the obtained reactor inlet, and outlet temperature respectively 32.9 °C and 38.2 °C. Both models are qualified as a primary coolant for the primary coolant temperature is still below the permitted limit is 49.0 °C.

The incorporation of focused history in checklist for early recognition and treatment of acute illness and injury.

PubMed

Jayaprakash, Namita; Ali, Rashid; Kashyap, Rahul; Bennett, Courtney; Kogan, Alexander; Gajic, Ognjen

2016-08-31

Diagnostic error and delay are critical impediments to the safety of critically ill patients. Checklist for early recognition and treatment of acute illness and injury (CERTAIN) has been developed as a tool that facilitates timely and error-free evaluation of critically ill patients. While the focused history is an essential part of the CERTAIN framework, it is not clear how best to choreograph this step in the process of evaluation and treatment of the acutely decompensating patient. An un-blinded crossover clinical simulation study was designed in which volunteer critical care clinicians (fellows and attendings) were randomly assigned to start with either obtaining a focused history choreographed in series (after) or in parallel to the primary survey. A focused history was obtained using the standardized SAMPLE model that is incorporated into American College of Trauma Life Support (ATLS) and Pediatric Advanced Life Support (PALS). Clinicians were asked to assess six acutely decompensating patients using pre - determined clinical scenarios (three in series choreography, three in parallel). Once the initial choreography was completed the clinician would crossover to the alternative choreography. The primary outcome was the cognitive burden assessed through the NASA task load index. Secondary outcome was time to completion of a focused history. A total of 84 simulated cases (42 in parallel, 42 in series) were tested on 14 clinicians. Both the overall cognitive load and time to completion improved with each successive practice scenario, however no difference was observed between the series versus parallel choreographies. The median (IQR) overall NASA TLX task load index for series was 39 (17 - 58) and for parallel 43 (27 - 52), p = 0.57. The median (IQR) time to completion of the tasks in series was 125 (112 - 158) seconds and in parallel 122 (108 - 158) seconds, p = 0.92. In this clinical simulation study assessing the incorporation of a focused history

Data center cooling system

DOEpatents

Chainer, Timothy J; Dang, Hien P; Parida, Pritish R; Schultz, Mark D; Sharma, Arun

2015-03-17

A data center cooling system may include heat transfer equipment to cool a liquid coolant without vapor compression refrigeration, and the liquid coolant is used on a liquid cooled information technology equipment rack housed in the data center. The system may also include a controller-apparatus to regulate the liquid coolant flow to the liquid cooled information technology equipment rack through a range of liquid coolant flow values based upon information technology equipment temperature thresholds.

Temperature histories from tree rings and corals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, E.R.

1995-05-01

Recent temperature trends in long tree-ring and coral proxy temperature histories are evaluated and compared in an effort to objectively determine how anomalous twentieth century temperature changes have been. These histories mostly reflect regional variations in summer warmth from the tree rings and annual warmth from the corals. In the Northern Hemisphere. the North American tree-ring temperature histories and those from the north Polar Urals, covering the past 1000 or more years, indicate that the twentieth century has been anomalously warm relative to the past. In contrast, the tree-ring history from northern Fennoscandia indicates that summer temperatures during the {open_quote}Medievalmore » Warm Period{close_quote} were probably warmer on average than those than during this century. In the Southern Hemisphere, the tree-ring temperature histories from South America show no indication of recent warming, which is in accordance with local instrumental records. In contrast, the tree-ring, records from Tasmania and New Zealand indicate that the twentieth century has been unusually warm particularly since 1960. The coral temperature histories from the Galapagos Islands and the Great Barrier Reef are in broad agreement with the tree-ring temperature histories in those sectors, with the former showing recent cooling and the latter showing recent warming that may be unprecedented. Overall, the regional temperature histories evaluated here broadly support the larger-scale evidence for anomalous twentieth century warming based on instrumental records. However, this warming cannot be confirmed as an unprecedented event in all regions. 38 refs., 3 figs., 2 tabs.« less

Fragmentation inside atomic cooling haloes exposed to Lyman-Werner radiation

NASA Astrophysics Data System (ADS)

Regan, John A.; Downes, Turlough P.

2018-04-01

Supermassive stars born in pristine environments in the early Universe hold the promise of being the seeds for the supermassive black holes observed as high redshift quasars shortly after the epoch of reionisation. H2 suppression is thought to be crucial in order to negate normal Population III star formation and allow high accretion rates to drive the formation of supermassive stars. Only in the cases where vigorous fragmentation is avoided will a monolithic collapse be successful, giving rise to a single massive central object. We investigate the number of fragmentation sites formed in collapsing atomic cooling haloes subject to various levels of background Lyman-Werner flux. The background Lyman-Werner flux manipulates the chemical properties of the gas in the collapsing halo by destroying H2. We find that only when the collapsing gas cloud shifts from the molecular to the atomic cooling regime is the degree of fragmentation suppressed. In our particular case, we find that this occurs above a critical Lyman-Werner background of J ˜ 10 J21. The important criterion being the transition to the atomic cooling regime rather than the actual value of J, which will vary locally. Once the temperature of the gas exceeds T ≳ 104 K and the gas transitions to atomic line cooling, then vigorous fragmentation is strongly suppressed.

A history of the early days of personality testing in American industry: an obsession with adjustment.

PubMed

Gibby, Robert E; Zickar, Michael J

2008-08-01

Objective personality testing began with Woodworth's Personal Data Sheet in 1917. That test was developed to identify soldiers prone to nervous breakdowns during enemy bombardment in World War I (WWI). Soon after, many competing personality tests were developed for use in industry. Many of these tests, like Woodworth's, focused on the construct of employee maladjustment and were deemed important in screening out applicants who would create workplace disturbances. In this article, the authors review the history of these early personality tests, especially the Bernreuter Personality Inventory and the Humm-Wadsworth Temperament Scale, and discuss the implications of personality testers' obsession with the construct of employee maladjustment. In addition, the authors discuss the industry's obsession with emotional maladjustment and how this obsession coincided with a cultural shift in norms relating to cultural expression.

Laser cooling of molecular anions.

PubMed

Yzombard, Pauline; Hamamda, Mehdi; Gerber, Sebastian; Doser, Michael; Comparat, Daniel

2015-05-29

We propose a scheme for laser cooling of negatively charged molecules. We briefly summarize the requirements for such laser cooling and we identify a number of potential candidates. A detailed computation study with C_{2}^{-}, the most studied molecular anion, is carried out. Simulations of 3D laser cooling in a gas phase show that this molecule could be cooled down to below 1 mK in only a few tens of milliseconds, using standard lasers. Sisyphus cooling, where no photodetachment process is present, as well as Doppler laser cooling of trapped C_{2}^{-}, are also simulated. This cooling scheme has an impact on the study of cold molecules, molecular anions, charged particle sources, and antimatter physics.

An ion microprobe study of the intra-crystalline behavior of REE and selected trace elements in pyroxene from mare basalts with different cooling and crystallization histories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shearer, C.K.; Papike, J.J.; Simon, S.B.

1989-05-01

To study the effects of crystallization sequence and rate on trace element zoning characteristics of pyroxenes, the authors used combined electron microprobe-ion microprobe techniques on four nearly isochemical Apollo 12 and 15 pigeonite basalts with different cooling rates and crystallization histories. Major and minor element zoning characteristics are nearly identical to those reported in the literature. All the pyroxenes have similar chondrite-normalized REE patterns: negative Eu anomalies, positive slopes as defined by Yb/Ce, and slopes of REE patterns from Ce to Sm much steeper than from Gd to Yb. These trace element zoning characteristics in pyroxene and the partitioning ofmore » trace elements between pyroxene and the melt are intimately related to the interplay among the efficiency of the crystallization process, the kinetics at the crystal-melt interface, the kinetics of plagioclase nucleation and the characteristics of the crystal chemical substitutions within both the pyroxene and the associated crystallizing phases (i.e. plagioclase).« less

Cooled railplug

DOEpatents

Weldon, W.F.

1996-05-07

The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers. 10 figs.

Cooling Vest

NASA Technical Reports Server (NTRS)

1983-01-01

Because quadriplegics are unable to perspire below the level of spinal injury, they cannot tolerate heat stress. A cooling vest developed by Ames Research Center and Upjohn Company allows them to participate in outdoor activities. The vest is an adaptation of Ames technology for thermal control garments used to remove excess body heat of astronauts. The vest consists of a series of corrugated channels through which cooled water circulates. Its two outer layers are urethane coated nylon, and there is an inner layer which incorporates the corrugated channels. It can be worn as a backpack or affixed to a wheelchair. The unit includes a rechargeable battery, mini-pump, two quart reservoir and heat sink to cool the water.

Cooled railplug

DOEpatents

Weldon, William F.

1996-01-01

The railplug is a plasma ignitor capable of injecting a high energy plasma jet into a combustion chamber of an internal combustion engine or continuous combustion system. An improved railplug is provided which has dual coaxial chambers (either internal or external to the center electrode) that provide for forced convective cooling of the electrodes using the normal pressure changes occurring in an internal combustion engine. This convective cooling reduces the temperature of the hot spot associated with the plasma initiation point, particularly in coaxial railplug configurations, and extends the useful life of the railplug. The convective cooling technique may also be employed in a railplug having parallel dual rails using dual, coaxial chambers.

History of Rotating Machine Development and Foresight

NASA Astrophysics Data System (ADS)

Tari, Makoto; Nagano, Susumu; Amemori, Shiro; Aso, Toshiyuki

The history of electrical rotating machines such as generators and motors in Japan is around one hundred years. At early stage, all machines were imported from foreign countries, but now domestic industries introduce new concept of machines and are leading these kinds of technology. Reviewing of history and development and foresight seems meaningful for further development.

A cool Southwest Indian Ocean connection to El Niño events

NASA Astrophysics Data System (ADS)

Wieners, Claudia; Manola, Iris; Ridderinkhof, Wim; Dijkstra, Henk; von der Heydt, Anna; Kirtman, Benjamin; Selten, Frank; de Ruijter, Wilhelmus

2014-05-01

Recent studies have shown that anomalously high sea surface temperatures (SST) in the southeastern equatorial Indian Ocean (IO) can influence early El Niño development by modulating the winds over the western Pacific. We have collected observational evidence for a dynamic connection between relatively cool SST developments in the southwestern Indian Ocean and the following years' El Niño. These cool anomalies appear over the so-called Seychelles thermocline Dome. Depending on strength and timing they generate a fast atmospheric response by stimulating an Indo-Pacific atmospheric bridge that leads to enhanced convection over the western Pacific. The slow oceanic response involves a pathway of upwelling Rossby and Kelvin waves that propagate towards and across the equator. We will present the first results of a series of dedicated climate model experiments. They were designed to stimulate the response of the coupled system to the SST cooling using a global climate model. First results seem to support the observational analysis.

Stacking with stochastic cooling

NASA Astrophysics Data System (ADS)

Caspers, Fritz; Möhl, Dieter

2004-10-01

Accumulation of large stacks of antiprotons or ions with the aid of stochastic cooling is more delicate than cooling a constant intensity beam. Basically the difficulty stems from the fact that the optimized gain and the cooling rate are inversely proportional to the number of particles 'seen' by the cooling system. Therefore, to maintain fast stacking, the newly injected batch has to be strongly 'protected' from the Schottky noise of the stack. Vice versa the stack has to be efficiently 'shielded' against the high gain cooling system for the injected beam. In the antiproton accumulators with stacking ratios up to 105 the problem is solved by radial separation of the injection and the stack orbits in a region of large dispersion. An array of several tapered cooling systems with a matched gain profile provides a continuous particle flux towards the high-density stack core. Shielding of the different systems from each other is obtained both through the spatial separation and via the revolution frequencies (filters). In the 'old AA', where the antiproton collection and stacking was done in one single ring, the injected beam was further shielded during cooling by means of a movable shutter. The complexity of these systems is very high. For more modest stacking ratios, one might use azimuthal rather than radial separation of stack and injected beam. Schematically half of the circumference would be used to accept and cool new beam and the remainder to house the stack. Fast gating is then required between the high gain cooling of the injected beam and the low gain stack cooling. RF-gymnastics are used to merge the pre-cooled batch with the stack, to re-create free space for the next injection, and to capture the new batch. This scheme is less demanding for the storage ring lattice, but at the expense of some reduction in stacking rate. The talk reviews the 'radial' separation schemes and also gives some considerations to the 'azimuthal' schemes.

Time development in the early history of social networks: link stabilization, group dynamics, and segregation.

PubMed

Bruun, Jesper; Bearden, Ian G

2014-01-01

Studies of the time development of empirical networks usually investigate late stages where lasting connections have already stabilized. Empirical data on early network history are rare but needed for a better understanding of how social network topology develops in real life. Studying students who are beginning their studies at a university with no or few prior connections to each other offers a unique opportunity to investigate the formation and early development of link patterns and community structure in social networks. During a nine week introductory physics course, first year physics students were asked to identify those with whom they communicated about problem solving in physics during the preceding week. We use these students' self reports to produce time dependent student interaction networks. We investigate these networks to elucidate possible effects of different student attributes in early network formation. Changes in the weekly number of links show that while roughly half of all links change from week to week, students also reestablish a growing number of links as they progress through their first weeks of study. Using the Infomap community detection algorithm, we show that the networks exhibit community structure, and we use non-network student attributes, such as gender and end-of-course grade to characterize communities during their formation. Specifically, we develop a segregation measure and show that students structure themselves according to gender and pre-organized sections (in which students engage in problem solving and laboratory work), but not according to end-of-coure grade. Alluvial diagrams of consecutive weeks' communities show that while student movement between groups are erratic in the beginning of their studies, they stabilize somewhat towards the end of the course. Taken together, the analyses imply that student interaction networks stabilize quickly and that students establish collaborations based on who is immediately

Toward Cooling Uniformity: Investigation of Spiral, Sweeping Holes, and Unconventional Cooling Paradigms

NASA Technical Reports Server (NTRS)

Shyam, Vikram; Thurman, Douglas R.; Poinsatte, Philip E.; Ameri, Ali A.; Culley, Dennis E.

2018-01-01

Surface infrared thermography, hotwire anemometry, and thermocouple surveys were performed on two new film cooling hole geometries: spiral/rifled holes and fluidic sweeping holes. Ways to quantify the efficacy of novel cooling holes that are asymmetric, not uniformly spaced or that show variation from hole to hole are presented. The spiral holes attempt to induce large-scale vorticity to the film cooling jet as it exits the hole to prevent the formation of the kidney shaped vortices commonly associated with film cooling jets. The fluidic sweeping hole uses a passive in-hole geometry to induce jet sweeping at frequencies that scale with blowing ratios. The spiral hole performance is compared to that of round holes with and without compound angles. The fluidic hole is of the diffusion class of holes and is therefore compared to a 777 hole and square holes. A patent-pending spiral hole design showed the highest potential of the nondiffusion type hole configurations. Velocity contours and flow temperature were acquired at discreet cross-sections of the downstream flow field. The passive fluidic sweeping hole shows the most uniform cooling distribution but suffers from low span-averaged effectiveness levels due to enhanced mixing. The data was taken at a Reynolds number of 11,000 based on hole diameter and freestream velocity. Infrared thermography was taken for blowing ratios of 1.0, 1.5, 2.0, and 2.5 at a density ratio of 1.05. The flow inside the fluidic sweeping hole was studied using 3D unsteady RANS. A section on ideas for future work is included that addresses issues of quantifying cooling uniformity and provides some ideas for changing the way we think about cooling such as changing the direction of cooling or coupling acoustic devices to cooling holes to regulate frequency.

Cooling Duct Analysis for Transpiration/Film Cooled Liquid Propellant Rocket Engines

NASA Technical Reports Server (NTRS)

Micklow, Gerald J.

1996-01-01

The development of a low cost space transportation system requires that the propulsion system be reusable, have long life, with good performance and use low cost propellants. Improved performance can be achieved by operating the engine at higher pressure and temperature levels than previous designs. Increasing the chamber pressure and temperature, however, will increase wall heating rates. This necessitates the need for active cooling methods such as film cooling or transpiration cooling. But active cooling can reduce the net thrust of the engine and add considerably to the design complexity. Recently, a metal drawing process has been patented where it is possible to fabricate plates with very small holes with high uniformity with a closely specified porosity. Such a metal plate could be used for an inexpensive transpiration/film cooled liner to meet the demands of advanced reusable rocket engines, if coolant mass flow rates could be controlled to satisfy wall cooling requirements and performance. The present study investigates the possibility of controlling the coolant mass flow rate through the porous material by simple non-active fluid dynamic means. The coolant will be supplied to the porous material by series of constant geometry slots machined on the exterior of the engine.

Water cooled steam jet

DOEpatents

Wagner, Jr., Edward P.

1999-01-01

A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed therebetween. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock.

Water cooled steam jet

DOEpatents

Wagner, E.P. Jr.

1999-01-12

A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed there between. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock. 2 figs.

Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

NASA Technical Reports Server (NTRS)

Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 C temperature increase from the nominal vapor temperature. The 19 C temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

NASA Technical Reports Server (NTRS)

Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

2013-01-01

In a Stirling Radioisotope Power System (RPS), heat must be continuously removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. The Stirling convertor normally provides this cooling. If the Stirling convertor stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS at the cost of an early termination of the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) can be used to passively allow multiple stops and restarts of the Stirling convertor. In a previous NASA SBIR Program, Advanced Cooling Technologies, Inc. (ACT) developed a series of sodium VCHPs as backup cooling systems for Stirling RPS. The operation of these VCHPs was demonstrated using Stirling heater head simulators and GPHS simulators. In the most recent effort, a sodium VCHP with a stainless steel envelope was designed, fabricated and tested at NASA Glenn Research Center (GRC) with a Stirling convertor for two concepts; one for the Advanced Stirling Radioisotope Generator (ASRG) back up cooling system and one for the Long-lived Venus Lander thermal management system. The VCHP is designed to activate and remove heat from the stopped convertor at a 19 degC temperature increase from the nominal vapor temperature. The 19 degC temperature increase from nominal is low enough to avoid risking standard ASRG operation and spoiling of the Multi-Layer Insulation (MLI). In addition, the same backup cooling system can be applied to the Stirling convertor used for the refrigeration system of the Long-lived Venus Lander. The VCHP will allow the refrigeration system to: 1) rest during transit at a lower temperature than nominal; 2) pre-cool the modules to an even lower temperature before the entry in Venus atmosphere; 3) work at nominal temperature on Venus surface; 4) briefly stop multiple times on the Venus surface to allow scientific measurements. This paper presents the experimental

World History. Volumes I and II. [Sahuarita High School Career Curriculum Project].

ERIC Educational Resources Information Center

Hoffman, Judy

Volumes I and II of a world history course, part of a high school career curriculum project, are outlined. Objectives are listed by course title. Course titles include: Early Communication - Languages and Writing; World History; Law and Order in Ancient Times; Early Transportation; Women in Ancient Times; Art and Literature in Ancient Times;…

Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haihua Zhao; Hongbin Zhang; Phil Sharpe

2010-06-01

economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ice thermal storage systems can effectively reduce the efficiency loss and water consumption during hot weather so that new LWRs could be considered in regions without enough cooling water. \\ This paper presents the feasibility study of using ice thermal storage systems for LWR supplemental cooling and peak power shifting. LWR cooling issues and ITS application status will be reviewed. Two ITS application case studies will be presented and compared with alternative options: one for once-through cooling without enough cooling for short time, and the other with dry cooling. Because capital cost, especially the ice storage structure/building cost, is the major cost for ITS, two different cost estimation models are developed: one based on scaling method, and the other based on a preliminary design using Building Information Modeling (BIM), an emerging technology in Architecture/Engineering/Construction, which enables design options, performance analysis and cost estimating in the early design stage.« less

Bipolar affective disorder and borderline personality disorder: Differentiation based on the history of early life stress and psychoneuroendocrine measures.

PubMed

Mazer, Angela Kaline; Cleare, Anthony J; Young, Allan H; Juruena, Mario F

2018-04-24

Borderline Personality Disorder (BPD) and Bipolar Affective Disorder (BD) have clinical characteristics in common which often make their differential diagnosis difficult. The history of early life stress (ELS) may be a differentiating factor between BPD and BD, as well as its association with clinical manifestations and specific neuroendocrine responses in each of these diagnoses. Assessing and comparing patients with BD and BPD for factors related to symptomatology, etiopathogenesis and neuroendocrine markers. The study sample consisted of 51 women, divided into 3 groups: patients with a clinical diagnosis of BPD (n = 20) and BD (n = 16) and healthy controls (HC, n = 15). Standardized instruments were used for the clinical evaluation, while the history of ELS was quantified with the Childhood Trauma Questionnaire (CTQ), and classified according to the subtypes: emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect. The functioning of the hypothalamic-pituitary-adrenal (HPA) axis was evaluated by measuring a single plasma cortisol sample. Patients with BPD presented with more severe psychiatric symptoms of: anxiety, impulsivity, depression, hopelessness and suicidal ideation than those with BD. The history of ELS was identified as significantly more prevalent and more severe in patients (BPD and BP) than in HC. Emotional abuse, emotional neglect and physical neglect also showed differences and were higher in BPD than BD patients. BPD patients had greater severity of ELS overall and in the subtypes of emotional abuse, emotional neglect and physical neglect than BD patients. The presence of ELS in patients with BPD and BP showed significant difference with lower cortisol levels when compared to HC. The endocrine evaluation showed no significant differences between the diagnoses of BPD and BD. Cortisol measured in patients with BPD was significantly lower compared to HC in the presence of emotional neglect and physical

Method for passive cooling liquid metal cooled nuclear reactors, and system thereof

DOEpatents

Hunsbedt, Anstein; Busboom, Herbert J.

1991-01-01

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel.

Cooling, degassing and compaction of rhyolitic ash flow tuffs: a computational model

USGS Publications Warehouse

Riehle, J.R.; Miller, T.F.; Bailey, R.A.

1995-01-01

Previous models of degassing, cooling and compaction of rhyolitic ash flow deposits are combined in a single computational model that runs on a personal computer. The model applies to a broader range of initial and boundary conditions than Riehle's earlier model, which did not integrate heat and mass flux with compaction and which for compound units was limited to two deposits. Model temperatures and gas pressures compare well with simple measured examples. The results indicate that degassing of volatiles present at deposition occurs within days to a few weeks. Compaction occurs for weeks to two to three years unless halted by devitrification; near-emplacement temperatures can persist for tens of years in the interiors of thick deposits. Even modest rainfall significantly chills the upper parts of ash deposits, but compaction in simple cooling units ends before chilling by rainwater influences cooling of the interior of the sheet. Rainfall does, however, affect compaction at the boundaries of deposits in compound cooling units, because the influx of heat from the overlying unit is inadequate to overcome heat previously lost to vaporization of water. Three density profiles from the Matahina Ignimbrite, a compound cooling unit, are fairly well reproduced by the model despite complexities arising from numerous cooling breaks. Uncertainties in attempts to correlate in detail among the profiles may be the result of the non-uniform distribution of individual deposits. Regardless, it is inferred that model compaction is approximately valid. Thus the model should be of use in reconstructing the emplacement history of compound ash deposits, for inferring the depositional environments of ancient deposits and for assessing how long deposits of modern ash flows are capable of generating phreatic eruptions or secondary ash flows. ?? 1995 Springer-Verlag.

A 100-kWt NaK-Cooled Space Reactor Concept for an Early-Flight Mission

NASA Astrophysics Data System (ADS)

Poston, David I.

2003-01-01

A stainless-steel (SS) sodium-potassium (NaK) cooled reactor could potentially be the first step in utilizing fission technology in space. The sum of all system-level experience for liquid-metal-cooled space reactors has been with NaK, including the SNAP-10a, the only reactor ever launched by the US. This paper describes a 100-kWt NaK reactor, the NaK-100, which is designed to be developed with minimal technical risk. In additional to NaK technology heritage, the NaK-100 uses a proven fuel-form (SS/UO2) and is designed for simplified system integration and testing. The pins are placed within a solid SS prism, and the NaK flows in an annulus between the pins and the prism. The nuclear and thermal-hydraulic performance of the NaK-100 is presented, as well as the major differences between the NaK-100 and SNAP-10a.

Thermal and collisional history of Tishomingo iron meteorite: More evidence for early disruption of differentiated planetesimals

NASA Astrophysics Data System (ADS)

Yang, Jijin; Goldstein, Joseph I.; Scott, Edward R. D.; Michael, Joseph R.; Kotula, Paul G.; Grimberg, Ansgar; Leya, Ingo

2014-01-01

Tishomingo is a chemically and structurally unique iron with 32.5 wt.% Ni that contains 20% residual taenite and 80% martensite plates, which formed on cooling to between -75 and -200 °C, probably the lowest temperature recorded by any meteorite. Our studies using transmission (TEM) and scanning electron microscopy (SEM), X-ray microanalysis (AEM) and electron backscatter diffraction (EBSD) show that martensite plates in Tishomingo formed in a single crystal of taenite and decomposed during reheating forming 10-100 nm taenite particles with ∼50 wt.% Ni, kamacite with ∼4 wt.%Ni, along with martensite or taenite with 32 wt.% Ni. EBSD data and experimental constraints show that Tishomingo was reheated to 320-400 °C for about a year transforming some martensite to kamacite and to taenite particles and some martensite directly to taenite without composition change. Fizzy-textured intergrowths of troilite, kamacite with 2.7 wt.% Ni and 2.6 wt.% Co, and taenite with 56 wt.% Ni and 0.15 wt.% Co formed by localized shock melting. A single impact probably melted the sub-mm sulfides, formed stishovite, and reheated and decomposed the martensite plates. Tishomingo and its near-twin Willow Grove, which has 28 wt.% Ni, differ from IAB-related irons like Santa Catharina and San Cristobal that contain 25-36 wt.% Ni, as they are highly depleted in moderately volatile siderophiles and enriched in Ir and other refractory elements. Tishomingo and Willow Grove therefore resemble IVB irons but are chemically distinct. The absence of cloudy taenite in these two irons shows that they cooled through 250 °C abnormally fast at >0.01 °C/yr. Thus this grouplet, like the IVA and IVB irons, suffered an early impact that disrupted their parent body when it was still hot. Our noble gas data show that Tishomingo was excavated from its parent body about 100 to 200 Myr ago and exposed to cosmic rays as a meteoroid with a radius of ∼50-85 cm.

Impact of Life History on Fear Memory and Extinction

PubMed Central

Remmes, Jasmin; Bodden, Carina; Richter, S. Helene; Lesting, Jörg; Sachser, Norbert; Pape, Hans-Christian; Seidenbecher, Thomas

2016-01-01

Behavioral profiles are strongly shaped by an individual's whole life experience. The accumulation of negative experiences over lifetime is thought to promote anxiety-like behavior in adulthood (“allostatic load hypothesis”). In contrast, the “mismatch hypothesis” of psychiatric disease suggests that high levels of anxiety-like behavior are the result of a discrepancy between early and late environment. The aim of the present study was to investigate how different life histories shape the expression of anxiety-like behavior and modulate fear memory. In addition, we aimed to clarify which of the two hypotheses can better explain the modulation of anxiety and fear. For this purpose, male mice grew up under either adverse or beneficial conditions during early phase of life. In adulthood they were further subdivided in groups that either matched or mismatched the condition experienced before, resulting in four different life histories. The main results were: (i) Early life benefit followed by late life adversity caused decreased levels of anxiety-like behavior. (ii) Accumulation of adversity throughout life history led to impaired fear extinction learning. Late life adversity as compared to late life benefit mainly affected extinction training, while early life adversity as compared to early life benefit interfered with extinction recall. Concerning anxiety-like behavior, the results do neither support the allostatic load nor the mismatch hypothesis, but rather indicate an anxiolytic effect of a mismatched early beneficial and later adverse life history. In contrast, fear memory was strongly affected by the accumulation of adverse experiences over the lifetime, therefore supporting allostatic load hypothesis. In summary, this study highlights that anxiety-like behavior and fear memory are differently affected by specific combinations of adverse or beneficial events experienced throughout life. PMID:27757077

Copper, zinc, gallium and germanium distributions in taenite lamellae of iron meteorites and their importance for cooling rate estimations

NASA Astrophysics Data System (ADS)

Braun-Dullaeus, Karl-Ulrich; Traxel, Kurt

1995-02-01

One method forestimating cooling rates of meteorite parent bodies is to model measured nickel distributions in taenite lamellae of iron meteorites. Goldstein and Ogilvie ( Geochim. Cosmochim. Acta29, 893, 1965) and Rasmussen ( Icarus45, 564, 1981) developed techniques based on this idea to examine the cooling history in the temperature range between ˜700 and ˜400°C. As a result of Instrumental Neutron Activation Analysis (INAA) Rasmussen et al. ( Meteoritics23, 105, 1988) postulated that some trace elements would also be good cooling rate indicators. They argued that elements with distinct diffusion behavior are sensitive to different temperature ranges. The new Heidelberg proton microprobe uses the method of Proton Induced X-ray Emission (PIXE) for elemental analysis. This microprobe is an appropriate instrument to measure distributions of trace elements with a spatial resolution of 2 μm. We demonstrated on the iron meteorites Cape York (Agpalilik), Toluca and Odessa that the elements copper, zinc, gallium and germanium imitate the profiles of nickel in taenite lamella. The interpretation of the Zn, Ga and Ge profiles leads to the conclusion that these elements undergo diffusion mechanisms comparable to those of Ni. The numerical simulation of Cu distributions with a simplified model points out that little new information can be obtained about the cooling history of the meteorites by modelling Cu profiles. To simulate Zn, Ga or Ge distributions, the use of ternary phase diagrams is necessary.

Evolutionary demography and the population history of the European early Neolithic.

PubMed

Shennan, Stephen

2009-04-01

In this paper I propose that evolutionary demography and associated theory from human behavioral ecology provide a strong basis for explaining the available evidence for the patterns observed in the first agricultural settlement of Europe in the 7th-5th millennium cal. BC, linking together a variety of what have previously been disconnected observations and casting doubt on some long-standing existing models. An outline of relevant aspects of life history theory, which provides the foundation for understanding demography, is followed by a review of large-scale demographic patterns in the early Neolithic, which point to rapid population increase and a process of demic diffusion. More localized socioeconomic and demographic patterns suggesting rapid expansion to local carrying capacities and an associated growth of inequality in the earliest farming communities of central Europe (the Linear Pottery Culture, or LBK) are then outlined and shown to correspond to predictions of spatial population ecology and reproductive skew theory. Existing models of why it took so long for farming to spread to northern and northwest Europe, which explain the spread in terms of the gradual disruption of hunter-gatherer ways of life, are then questioned in light of evidence for population collapse at the end of the LBK. Finally, some broader implications of the study are presented, including the suggestion that the pattern of an initial agricultural boom followed by a bust may be relevant in other parts of the world.

Heating, cooling, and uplift during Tertiary time, northern Sangre de Cristo Range, Colorado ( USA).

USGS Publications Warehouse

Lindsay, D.A.; Andriessen, P.A.M.; Wardlaw, B.R.

1986-01-01

Paleozoic sedimentary rocks in a wide area of the northern Sangre de Cristo Range show effects of heating during Tertiary time. Heating is tentatively interpreted as a response to burial during Laramide folding and thrusting and also to high heat flow during Rio Grande rifting. Fission-track ages of apatite across a section of the range show that rocks cooled abruptly below 120oC, the blocking temperature for apatite, approx 19 Ma ago. Cooling was probably in response to rapid uplift and erosion of the northern Sangre de Cristo Range during early Rio Grande rifting.-from Authors

Effect of Silver or Copper Nanoparticles-Dispersed Silane Coatings on Biofilm Formation in Cooling Water Systems

PubMed Central

Ogawa, Akiko; Kanematsu, Hideyuki; Sano, Katsuhiko; Sakai, Yoshiyuki; Ishida, Kunimitsu; Beech, Iwona B.; Suzuki, Osamu; Tanaka, Toshihiro

2016-01-01

Biofouling often occurs in cooling water systems, resulting in the reduction of heat exchange efficiency and corrosion of the cooling pipes, which raises the running costs. Therefore, controlling biofouling is very important. To regulate biofouling, we focus on the formation of biofilm, which is the early step of biofouling. In this study, we investigated whether silver or copper nanoparticles-dispersed silane coatings inhibited biofilm formation in cooling systems. We developed a closed laboratory biofilm reactor as a model of a cooling pipe and used seawater as a model for cooling water. Silver or copper nanoparticles-dispersed silane coating (Ag coating and Cu coating) coupons were soaked in seawater, and the seawater was circulated in the laboratory biofilm reactor for several days to create biofilms. Three-dimensional images of the surface showed that sea-island-like structures were formed on silane coatings and low concentration Cu coating, whereas nothing was formed on high concentration Cu coatings and low concentration Ag coating. The sea-island-like structures were analyzed by Raman spectroscopy to estimate the components of the biofilm. We found that both the Cu coating and Ag coating were effective methods to inhibit biofilm formation in cooling pipes. PMID:28773758

Performance of Air-cooled Engine Cylinders Using Blower Cooling

NASA Technical Reports Server (NTRS)

Schey, Oscar W; Ellerbrock, Herman H , Jr

1936-01-01

An investigation was made to obtain information on the minimum quantity of air and power required to cool conventional air cooled cylinders at various operating conditions when using a blower. The results of these tests show that the minimum power required for satisfactory cooling with an overall blower efficiency of 100 percent varied from 2 to 6 percent of the engine power depending on the operating conditions. The shape of the jacket had a large effect on the cylinder temperatures. Increasing the air speed over the front of the cylinder by keeping the greater part of the circumference of the cylinder covered by the jacket reduced the temperatures over the entire cylinder.

On the Lower Limit of Chondrule Cooling Rates: The Significance of Iron Loss in Dynamic Crystallization Experiments

NASA Technical Reports Server (NTRS)

Paque, Julie M.; Connolly, Harold C., Jr.; Lofgren, Gary E.

1998-01-01

It is unlikely that the presence of chondrules, and thus their formation, within the protoplanetary nebula would be predicted if it were not for their ubiquitous presence in most chondritic meteorites. The study of these enigmatic, igneous objects has a direct influence on how meteoritic and solar system researchers model the processes operating and the materials present within our protoplanetary nebula. Key to understanding chondrule formation is a determination of constraints on their thermal histories. The three important variables in this history are their peak melting temperatures, the duration of their melting at peak temperatures, and the rate at which these object cool. Although these three variables are interdependent, it is cooling rate that provides the most powerful constraint. Cooling rate has a direct affect on the development of both crystal morphology and the elemental distributions within these grains. To date, experiments have indicated that chondrule cooling rates are in the range of 10's to 100's of degrees per hour for porphyritic chondrules (the most abundant type). The cooling rate for radial and barred chondrules is thought to be more rapid. To generate these cooling rates (rapid relative to the cooling of the nebula as a whole, but slow compared to simple black body radiation) the environment of chondrule formation must have been localized, and the abundance of solid materials must have been greatly enhanced above a gas of solar composition. Thus accurate determinations of chondrule cooling rates is critical in understanding both their formation and the nebular environment in which they formed. In a quest to more accurately determine the lower limit on cooling rates and to determine in more detail the effects of Fe loss from a molten sample to Pt wire loops, Weinbruch et al. have explored this issue experimentally and reevaluated the findings of Radomsky and Hewins in light of their new results. The basic conclusions of their paper are an

Contrastive analysis of cooling performance between a high-level water collecting cooling tower and a typical cooling tower

NASA Astrophysics Data System (ADS)

Wang, Miao; Wang, Jin; Wang, Jiajin; Shi, Cheng

2018-02-01

A three-dimensional (3D) numerical model is established and validated for cooling performance optimization between a high-level water collecting natural draft wet cooling tower (HNDWCT) and a usual natural draft wet cooling tower (UNDWCT) under the actual operation condition at Wanzhou power plant, Chongqing, China. User defined functions (UDFs) of source terms are composed and loaded into the spray, fill and rain zones. Considering the conditions of impact on three kinds of corrugated fills (Double-oblique wave, Two-way wave and S wave) and four kinds of fill height (1.25 m, 1.5 m, 1.75 m and 2 m), numerical simulation of cooling performance are analysed. The results demonstrate that the S wave has the highest cooling efficiency in three fills for both towers, indicating that fill characteristics are crucial to cooling performance. Moreover, the cooling performance of the HNDWCT is far superior to that of the UNDWCT with fill height increases of 1.75 m and above, because the air mass flow rate in the fill zone of the HNDWCT improves more than that in the UNDWCT, as a result of the rain zone resistance declining sharply for the HNDWCT. In addition, the mass and heat transfer capacity of the HNDWCT is better in the tower centre zone than in the outer zone near the tower wall under a uniform fill layout. This behaviour is inverted for the UNDWCT, perhaps because the high-level collection devices play the role of flow guiding in the inner zone. Therefore, when non-uniform fill layout optimization is applied to the HNDWCT, the inner zone increases in height from 1.75 m to 2 m, the outer zone reduces in height from 1.75 m to 1.5 m, and the outlet water temperature declines approximately 0.4 K compared to that of the uniform layout.

Analysis of Radiant Cooling System Configurations Integrated with Cooling Tower for Different Indian Climatic Zones

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathur, Jyotirmay; Bhandari, Mahabir S; Jain, Robin

Radiant cooling system has proven to be a low energy consumption system for building cooling needs. This study describes the use of cooling tower in radiant cooling system to improve the overall system efficiency. A comprehensive simulation feasibility study of the application of cooling tower in radiant cooling system was performed for the fifteen cities in different climatic zones of India. It was found that in summer, the wet bulb temperature (WBT) of the different climatic zones except warm-humid is suitable for the integration of cooling tower with radiant cooling system. In these climates, cooling tower can provide on averagemore » 24 C to 27 C water In order to achieve the energy saving potential, three different configurations of radiant cooling system have been compared in terms of energy consumption. The different configurations of the radiant cooling system integrated with cooling tower are: (1) provide chilled water to the floor, wall and ceiling mounted tubular installation. (2) provide chilled water to the wall and ceiling mounted tabular installation. In this arrangement a separate chiller has also been used to provide chilled water at 16 C to the floor mounted tubular installation. (3) provide chilled water to the wall mounted tabular installation and a separate chiller is used to provide chilled water at 16 C to the floor and ceiling mounted tabular installation. A dedicated outdoor air system is also coupled for dehumidification and ventilation in all three configurations. A conventional all-air system was simulated as a baseline to compare these configurations for assessing the energy saving potential.« less

How to write a history of Europe: Europe, Europes, Eurasia

NASA Astrophysics Data System (ADS)

Burke, Peter

2006-05-01

This article looks at the history of European culture from three angles, those of European uniqueness, European variety and European consciousness. The first section discusses the question of whether the fundamental unit of study, for cultural as well as economic historians, is not Eurasia. The second section is concerned with cultural divisions within Europe, with Europes in the plural. It asks whether it is more illuminating to distinguish two Europes (like Leopold von Ranke), or three (like Jeno Szucs), or even five (like Hugo Hassinger), and examine both centripetal and centrifugal forces in early modern history. The final section deals with the history of the idea of Europe, or more exactly with the rise of consciousness of being European, as it is revealed in early modern histories, geographies, journals and newspapers.

Experiment attributes to establish tube with twisted tape insert performance cooling plasma facing components

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, Emily; Ramirez, Emilio; Ruggles, Art E.

The modeling capability for tubes with twisted tape inserts is reviewed with reference to the application of cooling plasma facing components in magnetic confinement fusion devices. The history of experiments examining the cooling performance of tubes with twisted tape inserts is reviewed with emphasis on the manner of heating, flow stability limits and the details of the test section and fluid delivery system. Models for heat transfer, burnout, and onset of net vapor generation in straight tube flows and tube with twisted tape are compared. As a result, the gaps in knowledge required to establish performance limits of the plasmamore » facing components are identified and attributes of an experiment to close those gaps are presented.« less

Experiment attributes to establish tube with twisted tape insert performance cooling plasma facing components

DOE PAGES

Clark, Emily; Ramirez, Emilio; Ruggles, Art E.; ...

2015-08-18

The modeling capability for tubes with twisted tape inserts is reviewed with reference to the application of cooling plasma facing components in magnetic confinement fusion devices. The history of experiments examining the cooling performance of tubes with twisted tape inserts is reviewed with emphasis on the manner of heating, flow stability limits and the details of the test section and fluid delivery system. Models for heat transfer, burnout, and onset of net vapor generation in straight tube flows and tube with twisted tape are compared. As a result, the gaps in knowledge required to establish performance limits of the plasmamore » facing components are identified and attributes of an experiment to close those gaps are presented.« less

Cold perception and cutaneous microvascular response to local cooling at different cooling temperatures.

PubMed

Music, Mark; Finderle, Zarko; Cankar, Ksenija

2011-05-01

The aim of the present study was to investigate the effect of quantitatively measured cold perception (CP) thresholds on microcirculatory response to local cooling as measured by direct and indirect response of laser-Doppler (LD) flux during local cooling at different temperatures. The CP thresholds were measured in 18 healthy males using the Marstock method (thermode placed on the thenar). The direct (at the cooling site) and indirect (on contralateral hand) LD flux responses were recorded during immersion of the hand in a water bath at 20°C, 15°C, and 10°C. The cold perception threshold correlated (linear regression analysis, Pearson correlation) with the indirect LD flux response at cooling temperatures 20°C (r=0.782, p<0.01) and 15°C (r=0.605, p<0.01). In contrast, there was no correlation between the CP threshold and the indirect LD flux response during cooling in water at 10°C. The results demonstrate that during local cooling, depending on the cooling temperature used, cold perception threshold influences indirect LD flux response. Copyright © 2011 Elsevier Inc. All rights reserved.

Bringing history to life: simulating landmark experiments in psychology.

PubMed

Boynton, David M; Smith, Laurence D

2006-05-01

The course in history of psychology can be challenging for students, many of whom enter it with little background in history and faced with unfamiliar names and concepts. The sheer volume of material can encourage passive memorization unless efforts are made to increase student involvement. As part of a trend toward experiential history, historians of science have begun to supplement their lectures with demonstrations of classic physics experiments as a way to bring the history of science to life. Here, the authors report on computer simulations of five landmark experiments from early experimental psychology in the areas of reaction time, span of attention, and apparent motion. The simulations are designed not only to permit hands-on replication of historically important results but also to reproduce the experimental procedures closely enough that students can gain a feel for the nature of early research and the psychological processes being studied.

Black Contributions to the Early History of Western Medicine: Lack of Recognition as a Cause of Black Under-Representation in US Medical Schools

PubMed Central

Newsome, Frederick

1979-01-01

During several millenia, blacks in ancient Egypt made numerous contributions to medicine and were acknowledged as the inventors of the art of medicine. They produced the earliest physicians, medical knowledge, and medical literature. They contributed to the development of medicine in ancient Greece. Ancient writers, including Herodotus, Isocrates, and Diodorus, affirm this. Modern presentations of ancient medicine, however, deprive blacks of the knowledge of their early contributions to medicine by ignoring or subtly misrepresenting the black identity of the ancient Egyptians. Blacks are currently under-represented in US medical schools. It is proposed that the recognition of the contributions of blacks to the early history of Western medicine would inspire black students to study medicine. PMID:423296

Compressor bleed cooling fluid feed system

DOEpatents

Donahoo, Eric E; Ross, Christopher W

2014-11-25

A compressor bleed cooling fluid feed system for a turbine engine for directing cooling fluids from a compressor to a turbine airfoil cooling system to supply cooling fluids to one or more airfoils of a rotor assembly is disclosed. The compressor bleed cooling fluid feed system may enable cooling fluids to be exhausted from a compressor exhaust plenum through a downstream compressor bleed collection chamber and into the turbine airfoil cooling system. As such, the suction created in the compressor exhaust plenum mitigates boundary layer growth along the inner surface while providing flow of cooling fluids to the turbine airfoils.

Development of an integrated model for heat transfer and dynamic growth of Clostridium perfringens during the cooling of cooked boneless ham.

PubMed

Amézquita, A; Weller, C L; Wang, L; Thippareddi, H; Burson, D E

2005-05-25

Numerous small meat processors in the United States have difficulties complying with the stabilization performance standards for preventing growth of Clostridium perfringens by 1 log10 cycle during cooling of ready-to-eat (RTE) products. These standards were established by the Food Safety and Inspection Service (FSIS) of the US Department of Agriculture in 1999. In recent years, several attempts have been made to develop predictive models for growth of C. perfringens within the range of cooling temperatures included in the FSIS standards. Those studies mainly focused on microbiological aspects, using hypothesized cooling rates. Conversely, studies dealing with heat transfer models to predict cooling rates in meat products do not address microbial growth. Integration of heat transfer relationships with C. perfringens growth relationships during cooling of meat products has been very limited. Therefore, a computer simulation scheme was developed to analyze heat transfer phenomena and temperature-dependent C. perfringens growth during cooling of cooked boneless cured ham. The temperature history of ham was predicted using a finite element heat diffusion model. Validation of heat transfer predictions used experimental data collected in commercial meat-processing facilities. For C. perfringens growth, a dynamic model was developed using Baranyi's nonautonomous differential equation. The bacterium's growth model was integrated into the computer program using predicted temperature histories as input values. For cooling cooked hams from 66.6 degrees C to 4.4 degrees C using forced air, the maximum deviation between predicted and experimental core temperature data was 2.54 degrees C. Predicted C. perfringens growth curves obtained from dynamic modeling showed good agreement with validated results for three different cooling scenarios. Mean absolute values of relative errors were below 6%, and deviations between predicted and experimental cell counts were within 0.37 log10

Liquid-Cooled Garment

NASA Technical Reports Server (NTRS)

1977-01-01

A liquid-cooled bra, offshoot of Apollo moon suit technology, aids the cancer-detection technique known as infrared thermography. Water flowing through tubes in the bra cools the skin surface to improve resolution of thermograph image.

Cooling Water Intakes

EPA Pesticide Factsheets

Industries use large volumes of water for cooling. The water intakes pull large numbers of fish and other organisms into the cooling systems. EPA issues regulations on intake structures in order to minimize adverse environmental impacts.