Archaeological Resources Overview of Shaw Air Force Base and Pointsett Electronic Combat Range, Sumter County, South Carolina

DTIC Science & Technology

2006-04-01

Upper Paleolithic assemblage seemingly without fluted projectile points, certainly an excellent candidate for a pre-Clovis assemblage on technological...America developed in place out of an Upper Paleolithic population like that hypothesized to have inhabited Meadowcroft Rockshelter. On the other hand...Columbia. Hayden, B. 1979 Paleolithic Reflections: Lithic Technology and Ethnographic Excavations Among Australian Aboriginies. Australian Institute of

Geoarchaeological and paleohydrological evidence for a clovis-age drought in North America and its bearing on extinction

NASA Astrophysics Data System (ADS)

Haynes, C. Vance

1991-05-01

At the Murray Springs Clovis site in southeastern Arizona, stratigraphic and geomorphic evidence indicates that an abnormally low water table 10,900 yr B.P. was followed soon thereafter by a water-table rise accompanied by the deposition of an algal mat (the black mat) that buried mammoth tracks, Clovis artifacts, and a well. This water-table fluctuation correlates with pluvial lake fluctuations in the Great Basin during and immediately following Clovis occupation of that region. Many elements of Pleistocene megafauna in North America became extinct during the dry period. Oxygen isotope records show a marked decrease in δ18O correlated with the Younger Dryas cold-dry event of northern Europe which ended 10,750 yr B.P., essentially the same time as the water table began to rise in southeastern Arizona. Clovis hunters may have found large game animals easier prey when concentrated at water holes and under stress. If so, both climate and human predation contributed to Pleistocene extinction in America.

Human Population Decline in North America during the Younger Dryas

NASA Astrophysics Data System (ADS)

Anderson, D. G.; Goodyear, A. C.; Stafford, T. W., Jr.; Kennett, J.; West, A.

2009-12-01

There is ongoing debate about a possible human population decline or contraction at the onset of the Younger Dryas (YD) at 12.9 ka. We used two methods to test whether the YD affected human population levels: (1) frequency analyses of Paleoindian projectile points, and (2) summed probability analyses of radiocarbon (14C) dates. The results suggest that a significant decline or reorganization of human populations occurred at 12.9 ka, continued through the initial centuries of the YD chronozone, then rebounded by the end of the YD. FREQUENCY ANALYSES: This method employed projectile point data from the Paleoindian Database of the Americas (PIDBA, http://pidba.utk.edu). We tallied diagnostic projectile points and obtained larger totals for Clovis points than for immediately post-Clovis points, which share an instrument-assisted fluting technique, typically using pressure or indirect percussion. Gainey, Vail, Debert, Redstone, and Cumberland point-styles utilized this method and are comparable to the Folsom style. For the SE U.S., the ratio of Clovis points (n=1993) to post-Clovis points (n=947) reveals a point decline of 52%. For the Great Plains, a comparison of Clovis and fluted points (n=4020) to Folsom points (n=2527) shows a point decline of 37%, which may translate into a population contraction of similar magnitude. In addition, eight major Clovis lithic quarry sites in the SE U.S. exhibit little to no evidence for immediate post-Clovis occupations, implying a major population decline. SUMMED PROBABILITIES: This method involved calibrating relevant 14C dates and combining the probabilities, after which major peaks and troughs in the trends are assumed to reflect changes in human demographics. Using 14C dates from Buchanan et al. (2008), we analyzed multiple regions, including the Southeast and Great Plains. Contrary to Buchanan et al., we found an abrupt, statistically significant decline at 12.9 ka, followed 200 to 900 years later by a rebound in the number of dates. The decline at the YD onset was more than 50%, similar in magnitude to the decline in Clovis-Folsom point ratios. While calibration and sampling factors may affect the trends, this abrupt decline is large and requires explanation. SUMMARY: Even though correlation does not equate with causation, the coeval YD decline in both points and 14C dates appears linked to significant changes in climate and biota, as represented by the megafaunal extinction. While the causes of the YD remain controversial, a human population decline appears to have occurred, at least across parts of North America. Furthermore, the YD onset is associated with the abrupt replacement of Clovis by regional or subregional scale cultural traditions, potentially reflecting decreased range mobility and increased population isolation. Projectile point distributions and summed probability analyses, we argue, are potentially useful approaches for exploring demographic changes at regional scales.

77 FR 35965 - Federal Home Loan Bank Members Selected for Community Support Review

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-15

... Belen New Mexico. Citizens Bank of Clovis Clovis New Mexico. Four Corners Community Bank Farmington New... State Bank Seneca Kansas. The Solomon State Bank Solomon Kansas. Bank of Kansas South Hutchinson Kansas..., 2012, each Bank will notify its Advisory Council and nonprofit housing developers, community groups...

78 FR 49292 - American Medical Alert Corporation, DBA Tunstall, Clovis, New Mexico; Amended Certification...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-13

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-82,859] American Medical Alert... Assistance on July 18, 2013, applicable to workers of American Medical Alert Corporation, doing business as... follows: All workers of American Medical Alert Corporation, doing business as Tunstall, Clovis, New Mexico...

On Vastness and Variability: Cultural Transmission, Historicity, and the Paleoindian Record in Eastern South America.

PubMed

Araujo, Astolfo G M

2015-01-01

Eastern South America, or what is today Brazilian territory, poses interesting questions about the early human occupation of the Americas. Three totally distinct and contemporaneous lithic technologies, dated between 11,000 and 10,000 14C BP, are present in different portions of the country: the Umbu tradition in the south, with its formal bifacial industry, with well-retouched scrapers and bifacial points; the Itaparica tradition in the central-west / northwest, totally unifacial, whose only formal artifacts are limaces; and the "Lagoa Santa" industry, completely lacking any formal artifacts, composed mainly of small quartz flakes. Our data suggests that these differences are not related to subsistence or raw-material constraints, but rather to different cultural norms and transmission of strongly divergent chaînes opératoires. Such diversity in material culture, when viewed from a cultural transmission (CT) theory standpoint, seems at odds with a simple Clovis model as the origin of these three cultural traditions given the time elapsed since the first Clovis ages and the expected population structure of the early South American settlers.

Post-Clovis survival of American Mastodon in the southern Great Lakes Region of North America

NASA Astrophysics Data System (ADS)

Woodman, Neal; Beavan Athfield, Nancy

2009-11-01

The end of the Pleistocene in North America was marked by a wave of extinctions of large mammals, with the last known appearances of many species falling between ca. 11,000-10,000 14C yr BP. Temporally, this period overlaps with the Clovis Paleoindian cultural complex (11,190-10,530 14C yr BP) and with sudden climatic changes that define the beginning of the Younger Dryas chronozone (ca. 11,000-10,000 14C yr BP), both of which have been considered as potential proximal causes of this extinction event. Radiocarbon dating of enamel and filtered bone collagen from an extinct American Mastodon ( Mammut americanum) from northern Indiana, USA, by accelerator mass spectrometer yielded direct dates of 10,055 ± 40 14C yr BP and 10,032 ± 40 14C yr BP, indicating that the animal survived beyond the Clovis time period and into the late Younger Dryas. Although the late survival of this species in mid-continental North America does not remove either humans or climatic change as contributing causes for the late Pleistocene extinctions, neither Clovis hunters nor the climatic perturbations initiating the Younger Dryas chronozone were immediately responsible for driving mastodons to extinction.

The Homeland Security Enterprise: Where Do We Fit?

DTIC Science & Technology

2009-09-01

information, including suggestions for reducing this burden, to Washington headquarters Services , Directorate for Information Operations and Reports, 1215...emphasized federalism as the nation’s guiding principle (Clovis, 2006, p. 1). Additionally, Keith Bea, Congressional Research Service , (2005, p. 5...governance, in which each jurisdiction provides the necessary goods and services for its citizens (Clovis, 2006, pp. 3–4). The power for this arrangement

Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling.

PubMed

Firestone, R B; West, A; Kennett, J P; Becker, L; Bunch, T E; Revay, Z S; Schultz, P H; Belgya, T; Kennett, D J; Erlandson, J M; Dickenson, O J; Goodyear, A C; Harris, R S; Howard, G A; Kloosterman, J B; Lechler, P; Mayewski, P A; Montgomery, J; Poreda, R; Darrah, T; Hee, S S Que; Smith, A R; Stich, A; Topping, W; Wittke, J H; Wolbach, W S

2007-10-09

A carbon-rich black layer, dating to approximately 12.9 ka, has been previously identified at approximately 50 Clovis-age sites across North America and appears contemporaneous with the abrupt onset of Younger Dryas (YD) cooling. The in situ bones of extinct Pleistocene megafauna, along with Clovis tool assemblages, occur below this black layer but not within or above it. Causes for the extinctions, YD cooling, and termination of Clovis culture have long been controversial. In this paper, we provide evidence for an extraterrestrial (ET) impact event at approximately equal 12.9 ka, which we hypothesize caused abrupt environmental changes that contributed to YD cooling, major ecological reorganization, broad-scale extinctions, and rapid human behavioral shifts at the end of the Clovis Period. Clovis-age sites in North American are overlain by a thin, discrete layer with varying peak abundances of (i) magnetic grains with iridium, (ii) magnetic microspherules, (iii) charcoal, (iv) soot, (v) carbon spherules, (vi) glass-like carbon containing nanodiamonds, and (vii) fullerenes with ET helium, all of which are evidence for an ET impact and associated biomass burning at approximately 12.9 ka. This layer also extends throughout at least 15 Carolina Bays, which are unique, elliptical depressions, oriented to the northwest across the Atlantic Coastal Plain. We propose that one or more large, low-density ET objects exploded over northern North America, partially destabilizing the Laurentide Ice Sheet and triggering YD cooling. The shock wave, thermal pulse, and event-related environmental effects (e.g., extensive biomass burning and food limitations) contributed to end-Pleistocene megafaunal extinctions and adaptive shifts among PaleoAmericans in North America.

Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling

PubMed Central

Firestone, R. B.; West, A.; Kennett, J. P.; Becker, L.; Bunch, T. E.; Revay, Z. S.; Schultz, P. H.; Belgya, T.; Kennett, D. J.; Erlandson, J. M.; Dickenson, O. J.; Goodyear, A. C.; Harris, R. S.; Howard, G. A.; Kloosterman, J. B.; Lechler, P.; Mayewski, P. A.; Montgomery, J.; Poreda, R.; Darrah, T.; Hee, S. S. Que; Smith, A. R.; Stich, A.; Topping, W.; Wittke, J. H.; Wolbach, W. S.

2007-01-01

A carbon-rich black layer, dating to ≈12.9 ka, has been previously identified at ≈50 Clovis-age sites across North America and appears contemporaneous with the abrupt onset of Younger Dryas (YD) cooling. The in situ bones of extinct Pleistocene megafauna, along with Clovis tool assemblages, occur below this black layer but not within or above it. Causes for the extinctions, YD cooling, and termination of Clovis culture have long been controversial. In this paper, we provide evidence for an extraterrestrial (ET) impact event at ≅12.9 ka, which we hypothesize caused abrupt environmental changes that contributed to YD cooling, major ecological reorganization, broad-scale extinctions, and rapid human behavioral shifts at the end of the Clovis Period. Clovis-age sites in North American are overlain by a thin, discrete layer with varying peak abundances of (i) magnetic grains with iridium, (ii) magnetic microspherules, (iii) charcoal, (iv) soot, (v) carbon spherules, (vi) glass-like carbon containing nanodiamonds, and (vii) fullerenes with ET helium, all of which are evidence for an ET impact and associated biomass burning at ≈12.9 ka. This layer also extends throughout at least 15 Carolina Bays, which are unique, elliptical depressions, oriented to the northwest across the Atlantic Coastal Plain. We propose that one or more large, low-density ET objects exploded over northern North America, partially destabilizing the Laurentide Ice Sheet and triggering YD cooling. The shock wave, thermal pulse, and event-related environmental effects (e.g., extensive biomass burning and food limitations) contributed to end-Pleistocene megafaunal extinctions and adaptive shifts among PaleoAmericans in North America. PMID:17901202

Post-Clovis survival of American Mastodon in the southern Great Lakes Region of North America

USGS Publications Warehouse

Woodman, N.; Beavan, Athfield N.

2009-01-01

The end of the Pleistocene in North America was marked by a wave of extinctions of large mammals, with the last known appearances of many species falling between ca. 11,000-10,000??14C yr BP. Temporally, this period overlaps with the Clovis Paleoindian cultural complex (11,190-10,530??14C yr BP) and with sudden climatic changes that define the beginning of the Younger Dryas chronozone (ca. 11,000-10,000??14C yr BP), both of which have been considered as potential proximal causes of this extinction event. Radiocarbon dating of enamel and filtered bone collagen from an extinct American Mastodon (Mammut americanum) from northern Indiana, USA, by accelerator mass spectrometer yielded direct dates of 10,055 ?? 40??14C yr BP and 10,032 ?? 40??14C yr BP, indicating that the animal survived beyond the Clovis time period and into the late Younger Dryas. Although the late survival of this species in mid-continental North America does not remove either humans or climatic change as contributing causes for the late Pleistocene extinctions, neither Clovis hunters nor the climatic perturbations initiating the Younger Dryas chronozone were immediately responsible for driving mastodons to extinction. ?? 2009 University of Washington.

Intensive Cultural Resource Inventory of Selected Recreation Areas in the West Portion of Lake Sakakawea, Dunn, McKenzie, Mountrail and Williams Counties, North Dakota. Volume 1.

DTIC Science & Technology

1983-01-01

populations in the Northwestern Plains. Distinctive lanceolate points such as Clovis, Folsom, and Plano were used along with scrapers, choppers, and...adjacent vicinity; fluted points tend to be concentrated in the west, while Plano points have been found throughout the state. To date, no Clovis or...Indian tradition to the Archaic tradition began with Folsom. During the Plano phase many adaptations are not sig- nificantly different from Plains

Archaeological support for the three-stage expansion of modern humans across northeastern Eurasia and into the Americas.

PubMed

Hamilton, Marcus J; Buchanan, Briggs

2010-08-30

Understanding the dynamics of the human range expansion across northeastern Eurasia during the late Pleistocene is central to establishing empirical temporal constraints on the colonization of the Americas. Opinions vary widely on how and when the Americas were colonized, with advocates supporting either a pre- or post- last glacial maximum (LGM) colonization, via either a land bridge across Beringia, a sea-faring Pacific Rim coastal route, a trans-Arctic route, or a trans-Atlantic oceanic route. Here we analyze a large sample of radiocarbon dates from the northeast Eurasian Upper Paleolithic to identify the origin of this expansion, and estimate the velocity of colonization wave as it moved across northern Eurasia and into the Americas. We use diffusion models to quantify these dynamics. Our results show the expansion originated in the Altai region of southern Siberia approximately 46kBP , and from there expanded across northern Eurasia at an average velocity of 0.16 km per year. However, the movement of the colonizing wave was not continuous but underwent three distinct phases: 1) an initial expansion from 47-32k calBP; 2) a hiatus from approximately 32-16k calBP, and 3) a second expansion after the LGM approximately 16k calBP. These results provide archaeological support for the recently proposed three-stage model of the colonization of the Americas. Our results falsify the hypothesis of a pre-LGM terrestrial colonization of the Americas and we discuss the importance of these empirical results in the light of alternative models. Our results demonstrate that the radiocarbon record of Upper Paleolithic northeastern Eurasia supports a post-LGM terrestrial colonization of the Americas falsifying the proposed pre-LGM terrestrial colonization of the Americas. We show that this expansion was not a simple process, but proceeded in three phases, consistent with genetic data, largely in response to the variable climatic conditions of late Pleistocene northeast Eurasia. Further, the constraints imposed by the spatiotemporal gradient in the empirical radiocarbon record across this entire region suggests that North America cannot have been colonized much before the existing Clovis radiocarbon record suggests.

Megafloods and Clovis cache at Wenatchee, Washington

NASA Astrophysics Data System (ADS)

Waitt, Richard B.

2016-05-01

Immense late Wisconsin floods from glacial Lake Missoula drowned the Wenatchee reach of Washington's Columbia valley by different routes. The earliest debacles, nearly 19,000 cal yr BP, raged 335 m deep down the Columbia and built high Pangborn bar at Wenatchee. As advancing ice blocked the northwest of Columbia valley, several giant floods descended Moses Coulee and backflooded up the Columbia past Wenatchee. Ice then blocked Moses Coulee, and Grand Coulee to Quincy basin became the westmost floodway. From Quincy basin many Missoula floods backflowed 50 km upvalley to Wenatchee 18,000 to 15,500 years ago. Receding ice dammed glacial Lake Columbia centuries more-till it burst about 15,000 years ago. After Glacier Peak ashfall about 13,600 years ago, smaller great flood(s) swept down the Columbia from glacial Lake Kootenay in British Columbia. The East Wenatchee cache of huge fluted Clovis points had been laid atop Pangborn bar after the Glacier Peak ashfall, then buried by loess. Clovis people came five and a half millennia after the early gigantic Missoula floods, two and a half millennia after the last small Missoula flood, and two millennia after the glacial Lake Columbia flood. People likely saw outburst flood(s) from glacial Lake Kootenay.

Tracing social interactions in Pleistocene North America via 3D model analysis of stone tool asymmetry

PubMed Central

Sholts, Sabrina B.; Gingerich, Joseph A. M.; Schlager, Stefan; Stanford, Dennis J.

2017-01-01

Stone tools, often the sole remnant of prehistoric hunter-gatherer behavior, are frequently used as evidence of ancient human mobility, resource use, and environmental adaptation. In North America, studies of morphological variation in projectile points have provided important insights into migration and interactions of human groups as early as 12–13 kya. Using new approaches to 3D imaging and morphometric analysis, we here quantify bifacial asymmetry among early North American projectile point styles to better understand changes in knapping technique and cultural transmission. Using a sample of 100 fluted bifaces of Clovis and post-Clovis styles in the eastern United States ca. 13,100–9,000 cal BP (i.e., Clovis, Debert-Vail, Bull Brook, Michaud-Neponset/Barnes, and Crowfield), we employed two different approaches for statistical shape analysis: our previously presented method for analysis of 2D flake scar contours, and a new approach for 3D surface analysis using spherical harmonics (SPHARM). Whereas bifacial asymmetry in point shape does not vary significantly across this stylistic sequence, our measure of asymmetric flake scar patterning shows temporal variation that may signify the beginning of regionalization among early New World colonists. PMID:28700598

Correlation of the Late Pleistocene Usselo Horizon (Europe) and the Clovis Layer (North America)

NASA Astrophysics Data System (ADS)

Kloosterman, J. B.

2007-05-01

In 1940, a dark charcoal-rich layer, 10 to 15cm thick, was found within the Late Pleistocene Coversands of the Netherlands, and named the Usselo Layer (de Laag van Usselo) by its discoverer, archaeologist CCJW Hijszeler (1902-1982). Usselo is a village near Enschedé, a few kilometres from the Dutch-German border. Research started after the war, and publications, both scientific and popular, came forth in the 1950s. By pollen content, the layer was dated to the Alleröd, the last interstadial of the Würm (Wisconsin) glaciation; radiocarbon dating indicated (pre-AMS) dates of about 11,200 14C BP. Identification of the layer at other localities was visual, and it was found in Belgium, France, Germany, Poland, and Belarus; it was also found in the UK and in Denmark, in which countries, however, no correlation was made with the other occurrences. Hijszeler had found the layer all over the Netherlands and abroad from Ostende to Hamburg, and he hypothesized the cause as a general wildfire provoked by the eruption of an Eiffel volcano. The European geologists and archaeologists, however, did not adopt his views and interpreted the layer as a paleosol, vitiating the chronology by representing the layer as the result of a long development, instead of as an eolian sediment laid down perhaps in a day or even less that provides us with a sharp marker horizon. The prehistoric Clovis culture of North America was found in the 1930s and dated to the Twocreekan, the last interstadial of the Wisconsin glaciation. The Clovis layer was especially investigated by archaeologist C.Vance Haynes Jr. Visually, the layer is easily identifiable with the Usselo Horizon of Europe. Its stratigraphic position is coincident with the end of the Clovis culture and with the disappearance of the Pleistocene megafauna. In Europe, there is a clear correlation with the sudden demise of the Magdalenian culture, best known for the Franco-Cantabrian cave paintings, and with megafaunal extinctions such as those of the Irish elk, the cave bear, and cave lion. Recently, Richard Firestone and Allen West in North America have carried out an intensive field and laboratory investigation, suspecting an extraterrestrial cause for the extinctions and the cultural discontinuity, with the Clovis layer as the extinction layer, an all-important witness to the catastrophe. They achieved positive results, the most spectacular one perhaps being the iridium content, because that element became well-known in the 1980s as an impact indicator in the K-T boundary layer. Other results include the presence of glass-like carbon, magnetic microspherules, and high levels of potassium-40. Being aware of the similarities in the Late Pleistocene stratigraphical records of Europe and North America, I contacted Firestone and West in 2005, and early in 2006 I sent them samples of the Usselo Horizon from Lommel, Belgium. The analyses they carried out yielded high levels of impact indicators, including magnetic grains, metallic spherules, carbon glass, charcoal, and in the magnetic fraction, high iridium content. These findings largely confirm the identity of the two ET impact layers on either side of the Atlantic Ocean. Hijszeler(1957) Geol.Mijnb.NS 19: 288-302. Haynes and Hemmings (1968) Science 159: 186-7. Wolbach, et al. (1985) Science 230: 167-170. Kloosterman (1999) Symp. New Scenarios of Solar System Evolution, Univ.Bergamo. (Abstract 2002). Kloosterman (2000) De Laag van Usselo, de Wereldbrand en de Verdwijntruc. Bres 201: 63-74. Kloosterman (2006) "De Komeetinslag van 13.000 jaar geleden." Frontier Mag. 12/1: 44- 45. Firestone, et al. (2006) The Cycle of Cosmic Catastrophes. Bear and Co., Rochester, Vermont.

An Assessment of the Impact of Hafting on Paleoindian Point Variability

PubMed Central

Buchanan, Briggs; O'Brien, Michael J.; Kilby, J. David; Huckell, Bruce B.; Collard, Mark

2012-01-01

It has long been argued that the form of North American Paleoindian points was affected by hafting. According to this hypothesis, hafting constrained point bases such that they are less variable than point blades. The results of several studies have been claimed to be consistent with this hypothesis. However, there are reasons to be skeptical of these results. None of the studies employed statistical tests, and all of them focused on points recovered from kill and camp sites, which makes it difficult to be certain that the differences in variability are the result of hafting rather than a consequence of resharpening. Here, we report a study in which we tested the predictions of the hafting hypothesis by statistically comparing the variability of different parts of Clovis points. We controlled for the potentially confounding effects of resharpening by analyzing largely unused points from caches as well as points from kill and camp sites. The results of our analyses were not consistent with the predictions of the hypothesis. We found that several blade characters and point thickness were no more variable than the base characters. Our results indicate that the hafting hypothesis does not hold for Clovis points and indicate that there is a need to test its applicability in relation to post-Clovis Paleoindian points. PMID:22666320

Megafloods and Clovis cache at Wenatchee, Washington

USGS Publications Warehouse

Waitt, Richard B.

2016-01-01

Immense late Wisconsin floods from glacial Lake Missoula drowned the Wenatchee reach of Washington's Columbia valley by different routes. The earliest debacles, nearly 19,000 cal yr BP, raged 335 m deep down the Columbia and built high Pangborn bar at Wenatchee. As advancing ice blocked the northwest of Columbia valley, several giant floods descended Moses Coulee and backflooded up the Columbia past Wenatchee. Ice then blocked Moses Coulee, and Grand Coulee to Quincy basin became the westmost floodway. From Quincy basin many Missoula floods backflowed 50 km upvalley to Wenatchee 18,000 to 15,500 years ago. Receding ice dammed glacial Lake Columbia centuries more—till it burst about 15,000 years ago. After Glacier Peak ashfall about 13,600 years ago, smaller great flood(s) swept down the Columbia from glacial Lake Kootenay in British Columbia. The East Wenatchee cache of huge fluted Clovis points had been laid atop Pangborn bar after the Glacier Peak ashfall, then buried by loess. Clovis people came five and a half millennia after the early gigantic Missoula floods, two and a half millennia after the last small Missoula flood, and two millennia after the glacial Lake Columbia flood. People likely saw outburst flood(s) from glacial Lake Kootenay.

Grinding into Soft, Powdery Rock

NASA Technical Reports Server (NTRS)

2004-01-01

This hole in a rock dubbed 'Clovis' is the deepest hole drilled so far in any rock on Mars. NASA's Mars Exploration Rover Spirit captured this view with its microscopic imager on martian sol 217 (Aug. 12, 2004) after drilling 8.9 millimeters (0.35 inch) into the rock with its rock abrasion tool. The view is a mosaic of four frames taken by the microscopic imager. The hole is 4.5 centimeters (1.8 inches) in diameter. Clovis is key to a developing story about environmental change on Mars, not only because it is among the softest rocks encountered so far in Gusev Crater, but also because it contains mineral alterations that extend relatively deep beneath its surface. In fact, as evidenced by its fairly crumbly texture, it is possibly the most highly altered volcanic rock ever studied on Mars.

Scientific analysis shows that the rock contains higher levels of the elements sulfur, chlorine, and bromine than are normally encountered in basaltic rocks, such as a rock dubbed 'Humphrey' that Spirit encountered two months after arriving on Mars. Humphrey showed elevated levels of sulfur, chlorine, and bromine only in the outermost 2 millimeters (less than 0.1 inch) of its surface. Clovis shows elevated levels of the same elements along with the associated softness of the rock within a borehole that is 4 times as deep. Scientists hope to compare Clovis to other, less-altered rocks in the vicinity to assess what sort of water-based processes altered the rock. Hypotheses include transport of sulfur, chlorine, and bromine in water vapor in volcanic gases; hydrothermal circulation (flow of volcanically heated water through rock); or saturation in a briny soup containing the same elements.

In this image, very fine-grained material from the rock has clumped together by electrostatic attraction and fallen into the borehole. NASA/JPL/Cornell/USGS

The Effect of the Younger Dryas on Paleoindian Occupations in Eastern North America Evidence from Artifactual, Pollen, and Radiocarbon Records

NASA Astrophysics Data System (ADS)

Anderson, D. G.; Meeks, S. C.; Miller, D. S.; Yerka, S. J.; Gillam, J. C.; Goodyear, A. C.; Johanson, E. N.; West, A.

2008-12-01

The Younger Dryas appears to have been a period when human populations in Eastern North America were undergoing significant stress. Attribute and locational data on Paleoindian materials from across the continent is available from the Paleoindian Database of the Americas or PIDBA, available on-line at http://pidba.utk.edu. Tallying the diagnostic projectile point sample from PIDBA in the on-line "entire sample" dated 24 April 2008, suggests that a population decline followed by a rebound may have occurred, particularly in southeastern North America. Following Clovis, fluted points with deeply indented bases and short to full flutes occur in many areas, such as the Redstone, Barnes, Cumberland, and Folsom types. In southeastern North America, these are thought to have been replaced by unfluted lanceolate and waisted forms, including the Beaver Lake, Suwannee/Simpson, and Quad types, which are in turn replaced by Dalton forms. Within the Southeast, a significant decline occurs between Clovis (N=1993 points) and presumably immediate post-Clovis full fluted forms (N=947 points). This may correspond to a similar decline in population, assuming the point types occurred for comparable periods of time, and were used in a similar fashion. Goodyear noted a similar pattern between Clovis (n=179) and presumed immediate post-Clovis Redstone (n=40) forms in South Carolina. Comparable declines have also been observed in North Carolina by Daniel and Goodyear ( and in Virginia by MacAvoy. In the PIDBA database across the Southeast, projectile point numbers increase following the immediate post Clovis decline, from 947 full fluted to 1717 unfluted and then 2594 Dalton points. The increase in the latter part of the Younger Dryas may actually be even more pronounced, since Dalton points, which are quite widespread, are only systematically recorded in a few states. Radiocarbon dates from Paleoindian and Early Archaic assemblages reveal a similar pattern. Dates falling in the initial centuries of the Younger Dryas are decidedly uncommon in the Southeast and over the larger region. In a sample of 218 dates from the Southeast and adjoining areas, only seven fall between 10,900 and 10,570 14C yr BP or between ca. 12,850 and 12,600 cal yr BP, and all of these are at the recent end of this range, between 10,570 and 10,710 14C yr BP. In the Southeast, at least, there appears to be a ca. 250-300 year 'gap' in the distribution of radiocarbon dates, with few reported from ca. 12,900-12,600 cal yr BP. Finally, analyses of fossil pollen records from the southeastern United States, although admittedly few in number, indicate that major vegetational shifts, both abrupt and characterized by oscillations, were occurring across the region during the Pleistocene/Holocene transition and that these shifts appear to be synchronic or quasi-synchronic with the Younger Dryas. The results suggests that the earliest inhabitants in the southeastern United States were faced with an environment that was anything but stable.

Archaeological Support for the Three-Stage Expansion of Modern Humans across Northeastern Eurasia and into the Americas

PubMed Central

Hamilton, Marcus J.; Buchanan, Briggs

2010-01-01

Background Understanding the dynamics of the human range expansion across northeastern Eurasia during the late Pleistocene is central to establishing empirical temporal constraints on the colonization of the Americas [1]. Opinions vary widely on how and when the Americas were colonized, with advocates supporting either a pre-[2] or post-[1], [3], [4], [5], [6] last glacial maximum (LGM) colonization, via either a land bridge across Beringia [3], [4], [5], a sea-faring Pacific Rim coastal route [1], [3], a trans-Arctic route [4], or a trans-Atlantic oceanic route [5]. Here we analyze a large sample of radiocarbon dates from the northeast Eurasian Upper Paleolithic to identify the origin of this expansion, and estimate the velocity of colonization wave as it moved across northern Eurasia and into the Americas. Methodology/Principal Findings We use diffusion models [6], [7] to quantify these dynamics. Our results show the expansion originated in the Altai region of southern Siberia ∼46kBP , and from there expanded across northern Eurasia at an average velocity of 0.16 km per year. However, the movement of the colonizing wave was not continuous but underwent three distinct phases: 1) an initial expansion from 47-32k calBP; 2) a hiatus from ∼32-16k calBP, and 3) a second expansion after the LGM ∼16k calBP. These results provide archaeological support for the recently proposed three-stage model of the colonization of the Americas [8], [9]. Our results falsify the hypothesis of a pre-LGM terrestrial colonization of the Americas and we discuss the importance of these empirical results in the light of alternative models. Conclusions/Significance Our results demonstrate that the radiocarbon record of Upper Paleolithic northeastern Eurasia supports a post-LGM terrestrial colonization of the Americas falsifying the proposed pre-LGM terrestrial colonization of the Americas. We show that this expansion was not a simple process, but proceeded in three phases, consistent with genetic data, largely in response to the variable climatic conditions of late Pleistocene northeast Eurasia. Further, the constraints imposed by the spatiotemporal gradient in the empirical radiocarbon record across this entire region suggests that North America cannot have been colonized much before the existing Clovis radiocarbon record suggests. PMID:20814574

Pre-Clovis occupation 14,550 years ago at the Page-Ladson site, Florida, and the peopling of the Americas

PubMed Central

Halligan, Jessi J.; Waters, Michael R.; Perrotti, Angelina; Owens, Ivy J.; Feinberg, Joshua M.; Bourne, Mark D.; Fenerty, Brendan; Winsborough, Barbara; Carlson, David; Fisher, Daniel C.; Stafford, Thomas W.; Dunbar, James S.

2016-01-01

Stone tools and mastodon bones occur in an undisturbed geological context at the Page-Ladson site, Florida. Seventy-one radiocarbon ages show that ~14,550 calendar years ago (cal yr B.P.), people butchered or scavenged a mastodon next to a pond in a bedrock sinkhole within the Aucilla River. This occupation surface was buried by ~4 m of sediment during the late Pleistocene marine transgression, which also left the site submerged. Sporormiella and other proxy evidence from the sediments indicate that hunter-gatherers along the Gulf Coastal Plain coexisted with and utilized megafauna for ~2000 years before these animals became extinct at ~12,600 cal yr B.P. Page-Ladson expands our understanding of the earliest colonizers of the Americas and human-megafauna interaction before extinction. PMID:27386553

Pre-Clovis occupation 14,550 years ago at the Page-Ladson site, Florida, and the peopling of the Americas.

PubMed

Halligan, Jessi J; Waters, Michael R; Perrotti, Angelina; Owens, Ivy J; Feinberg, Joshua M; Bourne, Mark D; Fenerty, Brendan; Winsborough, Barbara; Carlson, David; Fisher, Daniel C; Stafford, Thomas W; Dunbar, James S

2016-05-01

Stone tools and mastodon bones occur in an undisturbed geological context at the Page-Ladson site, Florida. Seventy-one radiocarbon ages show that ~14,550 calendar years ago (cal yr B.P.), people butchered or scavenged a mastodon next to a pond in a bedrock sinkhole within the Aucilla River. This occupation surface was buried by ~4 m of sediment during the late Pleistocene marine transgression, which also left the site submerged. Sporormiella and other proxy evidence from the sediments indicate that hunter-gatherers along the Gulf Coastal Plain coexisted with and utilized megafauna for ~2000 years before these animals became extinct at ~12,600 cal yr B.P. Page-Ladson expands our understanding of the earliest colonizers of the Americas and human-megafauna interaction before extinction.

78 FR 5821 - Final Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

... Greene County Courthouse, 306 West Court Street, Paragould, AR 72450. Curry County, New Mexico, and..., Clovis, NM 88101. Unincorporated Areas of Curry County. Curry County Administrative Office, 700 North...

Spectral Variability among Rocks in Visible and Near Infrared Multispectral Pancam Data Collected at Gusev Crater: Examinations using Spectral Mixture Analysis and Related Techniques

NASA Technical Reports Server (NTRS)

Farrand, W. H.; Bell, J. F., III; Johnson, J. R.; Squyres, S. W.; Soderblom, J.; Ming, D. W.

2006-01-01

Visible and Near Infrared (VNIR) multispectral observations of rocks made by the Mars Exploration Rover Spirit s Panoramic camera (Pancam) have been analysed using a spectral mixture analysis (SMA) methodology. Scenes have been examined from the Gusev crater plains into the Columbia Hills. Most scenes on the plains and in the Columbia Hills could be modeled as three endmember mixtures of a bright material, rock, and shade. Scenes of rocks disturbed by the rover s Rock Abrasion Tool (RAT) required additional endmembers. In the Columbia Hills there were a number of scenes in which additional rock endmembers were required. The SMA methodology identified relatively dust-free areas on undisturbed rock surfaces, as well as spectrally unique areas on RAT abraded rocks. Spectral parameters from these areas were examined and six spectral classes were identified. These classes are named after a type rock or area and are: Adirondack, Lower West Spur, Clovis, Wishstone, Peace, and Watchtower. These classes are discriminable based, primarily, on near-infrared (NIR) spectral parameters. Clovis and Watchtower class rocks appear more oxidized than Wishstone class rocks and Adirondack basalts based on their having higher 535 nm band depths. Comparison of the spectral parameters of these Gusev crater rocks to parameters of glass-dominated basaltic tuffs indicates correspondence between measurements of Clovis and Watchtower classes, but divergence for the Wishstone class rocks which appear to have a higher fraction of crystalline ferrous iron bearing phases. Despite a high sulfur content, the rock Peace has NIR properties resembling plains basalts.

Evidence for an extraterrestrial impact 12,900 years ago thatcontributed to megafaunal extinctions and the Younger Dryas cooling

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

Firestone, R.B.; West, A.; Kennett, J.P.

2007-08-06

A carbon-rich black layer, dating to ~;12.9 ka, has beenpreviously identified at ~;50 Clovis-age sites across North America andappears contemporaneous with the abrupt onset of Younger Dryas (YD)cooling. The in situ bones of extinct Pleistocene megafauna and Clovistool assemblages occur below this black layer but not within or above it.Causes for the extinctions, the YD cooling, and the termination of Clovisculture have long been controversial. In this paper, we provide evidencefor an extraterrestrial (ET) impact event at ?12.9 ka, which, wehypothesize, caused abrupt environmental changes that contributed to YDcooling, major ecological reorganization, broad-scale extinctions, andrapid human behavioral shifts at themore » end of the Clovis Period. Clovis-agesites in North American are overlain by a thin, discrete layer withvarying peak abundances of: (1) magnetic grains with iridium, (2)magnetic microspherules (3) charcoal, (4) soot, (5) carbon spherules, (6)glass-like carbon, and (7) fullerenes with ET helium, all of which areevidence for an ET impact and associated biomass burning at ~;12.9 ka.This layer also extends throughout at least fifteen Carolina Bays, whichare unique, elliptical wetlands, oriented to thenorthwest across theAtlantic Coastal Plain. We propose that one or more large, low-density ETobjects exploded over northern North America, partially destabilizing theLaurentide Ice Sheet and triggering YD cooling. The shock wave, thermalpulse, and event-related environmental effects (e.g., extensive biomassburning, food limitations) contributed to the end-Pleistocene megafaunalextinctions and adaptive shifts among PaleoAmericans in NorthAmerica.« less

Pre-coding method and apparatus for multiple source or time-shifted single source data and corresponding inverse post-decoding method and apparatus

NASA Technical Reports Server (NTRS)

Yeh, Pen-Shu (Inventor)

1997-01-01

A pre-coding method and device for improving data compression performance by removing correlation between a first original data set and a second original data set, each having M members, respectively. The pre-coding method produces a compression-efficiency-enhancing double-difference data set. The method and device produce a double-difference data set, i.e., an adjacent-delta calculation performed on a cross-delta data set or a cross-delta calculation performed on two adjacent-delta data sets, from either one of (1) two adjacent spectral bands coming from two discrete sources, respectively, or (2) two time-shifted data sets coming from a single source. The resulting double-difference data set is then coded using either a distortionless data encoding scheme (entropy encoding) or a lossy data compression scheme. Also, a post-decoding method and device for recovering a second original data set having been represented by such a double-difference data set.

Pre-coding method and apparatus for multiple source or time-shifted single source data and corresponding inverse post-decoding method and apparatus

NASA Technical Reports Server (NTRS)

Yeh, Pen-Shu (Inventor)

1998-01-01

A pre-coding method and device for improving data compression performance by removing correlation between a first original data set and a second original data set, each having M members, respectively. The pre-coding method produces a compression-efficiency-enhancing double-difference data set. The method and device produce a double-difference data set, i.e., an adjacent-delta calculation performed on a cross-delta data set or a cross-delta calculation performed on two adjacent-delta data sets, from either one of (1) two adjacent spectral bands coming from two discrete sources, respectively, or (2) two time-shifted data sets coming from a single source. The resulting double-difference data set is then coded using either a distortionless data encoding scheme (entropy encoding) or a lossy data compression scheme. Also, a post-decoding method and device for recovering a second original data set having been represented by such a double-difference data set.

Spectral variability among rocks in visible and near-infrared mustispectral Pancam data collected at Gusev crater: Examinations using spectral mixture analysis and related techniques

USGS Publications Warehouse

Farrand, W. H.; Bell, J.F.; Johnson, J. R.; Squyres, S. W.; Soderblom, J.; Ming, D. W.

2006-01-01

Visible and near-infrared (VNIR) multispectral observations of rocks made by the Mars Exploration Rover Spirit's Panoramic camera (Pancam) have been analyzed using a spectral mixture analysis (SMA) methodology. Scenes have been examined from the Gusev crater plains into the Columbia Hills. Most scenes on the plains and in the Columbia Hills could be modeled as three end-member mixtures of a bright material, rock, and shade. Scenes of rocks disturbed by the rover's Rock Abrasion Tool (RAT) required additional end-members. In the Columbia Hills, there were a number of scenes in which additional rock end-members were required. The SMA methodology identified relatively dust-free areas on undisturbed rock surfaces as well as spectrally unique areas on RAT abraded rocks. Spectral parameters from these areas were examined, and six spectral classes were identified. These classes are named after a type rock or area and are Adirondack, Lower West Spur, Clovis, Wishstone, Peace, and Watchtower. These classes are discriminable based, primarily, on near-infrared (NIR) spectral parameters. Clovis and Watchtower class rocks appear more oxidized than Wishstone class rocks and Adirondack basalts based on their having higher 535 nm band depths. Comparison of the spectral parameters of these Gusev crater rocks to parameters of glass-dominated basaltic tuffs indicates correspondence between measurements of Clovis and Watchtower classes but divergence for the Wishstone class rocks, which appear to have a higher fraction of crystalline ferrous iron-bearing phases. Despite a high sulfur content, the rock Peace has NIR properties resembling plains basalts. Copyright 2006 by the American Geophysical Union.

Making Tracks on Mars (left-eye)

NASA Technical Reports Server (NTRS)

2004-01-01

NASA's Mars Exploration Rover Spirit has been making tracks on Mars for seven months now, well beyond its original 90-day mission. The rover traveled more than 3 kilometers (2 miles) to reach the 'Columbia Hills' pictured here. In this 360-degree view of the rolling martian terrain, its wheel tracks can be seen approaching from the northwest (right side of image).

Spirit's navigation camera took the images that make up this mosaic on sols 210 and 213 (Aug. 5 and Aug. 8, 2004). The rover is now conducting scientific studies of the local geology on the 'Clovis' outcrop of the 'West Spur' region of the 'Columbia Hills.' The view is presented in a cylindrical-perspective projection with geometrical seam correction. This is the left-eye view of a stereo pair. Scientists plan for Spirit to take a color panoramic image from this location.

47 CFR 73.622 - Digital television table of allotments.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 44c Coalinga *22 Concord 63c Corona 39 Cotati *23c El Centro 22, 48 Eureka *11, 16, 17, 28 Fort Bragg..., 43 Clovis 43 Concord 14 Corona 39 Cotati *23 El Centro 9, 22 Eureka 3, *11, 17, 28 Fort Bragg 8...

47 CFR 73.622 - Digital television table of allotments.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 44c Coalinga *22 Concord 63c Corona 39 Cotati *23c El Centro 22, 48 Eureka *11, 16, 17, 28 Fort Bragg..., 43 Clovis 43 Concord 14 Corona 39 Cotati *23 El Centro 9, 22 Eureka 3, *11, 17, 28 Fort Bragg 8...

Progress in Mathematical Programming.

DTIC Science & Technology

1987-03-04

Philip Gill, Neal Glassman, Donald Goldfarb, Clovis Gonzaga, Harvey Greenberg , Peter Gritzmann, James K. Ho, Alan Hoffman, T. C. Hu, Hiroshi Imai...polar polytope P’ if 0 E P. The image trajectories are geodesics of a projectively invariant geometry on P 0 , Hilbert geometry. This work relates

A Common Origin for B-1a and B-2 Lymphocytes in Clonal Pre- Hematopoietic Stem Cells.

PubMed

Hadland, Brandon K; Varnum-Finney, Barbara; Mandal, Pankaj K; Rossi, Derrick J; Poulos, Michael G; Butler, Jason M; Rafii, Shahin; Yoder, Mervin C; Yoshimoto, Momoko; Bernstein, Irwin D

2017-06-06

Recent evidence points to the embryonic emergence of some tissue-resident innate immune cells, such as B-1a lymphocytes, prior to and independently of hematopoietic stem cells (HSCs). However, whether the full hematopoietic repertoire of embryonic HSCs initially includes these unique lineages of innate immune cells has been difficult to assess due to lack of clonal assays that identify and assess HSC precursor (pre-HSC) potential. Here, by combining index sorting of single embryonic hemogenic precursors with in vitro HSC maturation and transplantation assays, we analyze emerging pre-HSCs at the single-cell level, revealing their unique stage-specific properties and clonal lineage potential. Remarkably, clonal pre-HSCs detected between E9.5 and E11.5 contribute to the complete B cell repertoire, including B-1a lymphocytes, revealing a previously unappreciated common precursor for all B cell lineages at the pre-HSC stage and a second embryonic origin for B-1a lymphocytes. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

47 CFR 73.622 - Digital television table of allotments.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 44c Coalinga *22 Concord 63c Corona 39 Cotati *23c El Centro 22, 48 Eureka *11, 16, 17, 28 Fort Bragg... Clovis 43 Concord 14 Corona 39 Cotati *23 El Centro 9, 22 Eureka 3, *11, 17, 28 Fort Bragg 8 Fresno 7, 30...

47 CFR 73.622 - Digital television table of allotments.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 44c Coalinga *22 Concord 63c Corona 39 Cotati *23c El Centro 22, 48 Eureka *11, 16, 17, 28 Fort Bragg... Clovis 43 Concord 14 Corona 39 Cotati *23 El Centro 9, 22 Eureka 3, *11, 17, 28 Fort Bragg 8 Fresno 7, 30...

A Historical Overview for the MX Base Expansion, Clovis, New Mexico.

DTIC Science & Technology

1981-07-01

Bailey 1960-1981 L. R. Baxter 1952-1960 H. C. Delaney 1941-1952 Estelle Ruhlman 1913-1941 (Patentee) * . . . . . . . . . . . . . . SW!: Richard M...pany, Portales. Collins, Michael B. 1971 A review of Llano Estacado arciaeology and ethnohistory. Plains Anthropologist 16(52):85. Crocchiola, F. Stanley

Assessing Potential Predisposition of Elementary School Children to Heart Disease.

ERIC Educational Resources Information Center

Crow, Thomas A.; And Others

1982-01-01

A health assessment battery was developed to screen elementary school children in Clovis (California) for factors that might lead to heart disease. Students' height, blood pressure, flexibility, weight, and body fatness (by skin-fold tests) were measured. Plans call for future development of longitudinal student profiles. (Authors/PP)

Visual Arts in Community Colleges: Enhancing the Learning Environment.

ERIC Educational Resources Information Center

Gurley, Jay

Art exhibits on college campuses not only foster aesthetic appreciation and knowledge, but they also stimulate and encourage community involvement. In New Mexico, public and institutional policies permit the purchase of art to enhance public buildings, including institutions of higher education. At Eastern New Mexico University's Clovis Campus…

One-to-One in the Golden State

ERIC Educational Resources Information Center

McHale, Thomas

2007-01-01

This article relates the story of one California school district that is making laptop ownership for students a reality, despite the overwhelming financial burden. In January 1996, Clovis Unified School District found itself in a situation familiar to many districts. Fresh from a conference in Redmond, Washington, sponsored by Microsoft and…

Open chromatin structures regulate the efficiencies of pre-RC formation and replication initiation in Epstein-Barr virus

PubMed Central

Papior, Peer; Arteaga-Salas, José M.; Günther, Thomas; Grundhoff, Adam

2012-01-01

Whether or not metazoan replication initiates at random or specific but flexible sites is an unsolved question. The lack of sequence specificity in origin recognition complex (ORC) DNA binding complicates genome-scale chromatin immunoprecipitation (ChIP)-based studies. Epstein-Barr virus (EBV) persists as chromatinized minichromosomes that are replicated by the host replication machinery. We used EBV to investigate the link between zones of pre-replication complex (pre-RC) assembly, replication initiation, and micrococcal nuclease (MNase) sensitivity at different cell cycle stages in a genome-wide fashion. The dyad symmetry element (DS) of EBV’s latent origin, a well-established and very efficient pre-RC assembly region, served as an internal control. We identified 64 pre-RC zones that correlate spatially with 57 short nascent strand (SNS) zones. MNase experiments revealed that pre-RC and SNS zones were linked to regions of increased MNase sensitivity, which is a marker of origin strength. Interestingly, although spatially correlated, pre-RC and SNS zones were characterized by different features. We propose that pre-RCs are formed at flexible but distinct sites, from which only a few are activated per single genome and cell cycle. PMID:22891264

The Redemptive Role of the Community College within a Rural Society.

ERIC Educational Resources Information Center

Brandon, Judy

The Academic Career Studies (ACS) program at Clovis Community College focuses on time management, concentration and memory techniques, effective reading and note taking, test-taking skills, creativity, and the qualities of people who are "masters" at what they do. The program targets students who are working on their General Educational…

Origins and spread of fluted-point technology in the Canadian Ice-Free Corridor and eastern Beringia.

PubMed

Smith, Heather L; Goebel, Ted

2018-04-17

Fluted projectile points have long been recognized as the archaeological signature of early humans dispersing throughout the Western Hemisphere; however, we still lack a clear understanding of their appearance in the interior "Ice-Free Corridor" of western Canada and eastern Beringia. To solve this problem, we conducted a geometric morphometric shape analysis and a phylogenetic analysis of technological traits on fluted points from the archaeological records of northern Alaska and Yukon, in combination with artifacts from further south in Canada, the Great Plains, and eastern United States to investigate the plausibility of historical relatedness and evolutionary patterns in the spread of fluted-point technology in the latest Pleistocene and earliest Holocene. Results link morphologies and technologies of Clovis, certain western Canadian, and northern fluted points, suggesting that fluting technology arrived in the Arctic from a proximate source in the interior Ice-Free Corridor and ultimately from the earliest populations in temperate North America, complementing new genomic models explaining the peopling of the Americas.

NASA - Human Space Flight

NASA Technical Reports Server (NTRS)

Davis, Jeffrey R.

2006-01-01

The presentation covers five main topical areas. The first is a description of how things work in the microgravity environment such as convection and sedimentation. The second part describes the effects of microgravity on human physiology. This is followed by a description of the hazards of space flight including the environment, the space craft, and the mission. An overview of biomedical research in space, both on shuttle and ISS is the fourth section of the presentation. The presentation concludes with a history of space flight from Ham to ISS. At CART students (11th and 12th graders from Fresno Unified and Clovis Unified) are actively involved in their education. They work in teams to research real world problems and discover original solutions. Students work on projects guided by academic instructors and business partners. They will have access to the latest technology and will be expected to expand their learning environment to include the community. They will focus their studies around a career area (Professional Sciences, Advanced Communications, Engineering and Product Development, or Global Issues).

Fusion Centers and Federalism: Erosion or Enhancement?

DTIC Science & Technology

2013-03-01

DRAWBACKS OF VARIATION ................................................................29  F.  DECENTRALIZATION AND HOMELAND SECURITY INTELLIGENCE...capabilities, Samuel Clovis also found, but “the inevitable swing of the pendulum of power…moved decidedly toward the central government, with virtually no...made even more valid by the fact that disasters can be widespread affairs spilling over the borders of individual states.59 E. DRAWBACKS OF

Democracy and Leadership in Basic Writing Small Groups.

ERIC Educational Resources Information Center

Kurth, Lita

Commonly accepted ideas, on the one hand, about how small groups in a writing class should work and, on the other hand, psychological research about what makes a small group work well are not consistent. Social psychologist Clovis Shepherd claims that the "popular notion that the democratic ideal is a group in which all members exert an equal…

Performance of the rebuilt SUERC single-stage accelerator mass spectrometer

NASA Astrophysics Data System (ADS)

Shanks, Richard P.; Ascough, Philippa L.; Dougans, Andrew; Gallacher, Paul; Gulliver, Pauline; Rood, Dylan H.; Xu, Sheng; Freeman, Stewart P. H. T.

2015-10-01

The SUERC bipolar single-stage accelerator mass spectrometer (SSAMS) has been dismantled and rebuilt to accommodate an additional rotatable pre-accelerator electrostatic spherical analyser (ESA) and a second ion source injector. This is for the attachment of an experimental positive-ion electron cyclotron resonance (ECR) ion source in addition to a Cs-sputter source. The ESA significantly suppresses oxygen interference to radiocarbon detection, and remaining measurement interference is now thought to be from 13C injected as 13CH molecule scattering off the plates of a second original pre-detector ESA.

Interpretive Sourcebook, 1996. A Sense of Place, A Sense of Space: Interpretation under the Big Sky. Proceedings of the National Interpreters Workshop (Billings, Montana, October 22-26, 1996).

ERIC Educational Resources Information Center

Koopmann, Richard W., Ed.

This sourcebook is a compilation of presentations from the National Interpreters Workshop held in Billings, Montana, in 1996. In this book, interpreters share stories of American battlefields, driving tours, wetlands, clovis points, floating classrooms, perfect signs, art collaboration, and wild animals in interpretive programming. Sections…

Sample Archaeological Survey of Public Use Areas, Milford Lake, Kansas

DTIC Science & Technology

1982-09-01

6,000 B.C. Llano -(Clovis projectile points) Lindenmeier - (Folsom projectile points) Plano -(Plainview, Angostora, Hell Gap, Scotts- bluff, etc...plain, flaring or S-form rims, shell tempered, plain surfaced pottery with low rolled rims 0 and incised alternating hatched triangles on the...tempered pottery with a marked collar rim incised with zig-zags, herringbone and hatched alternating triangles; unnotched triangular arrow points; French

A nuclear-free land for Kennewick Man

NASA Astrophysics Data System (ADS)

Asmus, John

2011-06-01

In 1964 a human skeleton was discovered in the sediments of the Columbia River near Kennewick, Washington (the extreme northwest portion of the United States). Subsequently, these bones were analyzed in several scientific laboratories and dated at more than 6000 years BP. Now known as "Kennewick Man", the remains are associated with the "Clovis Period" and, indeed, a Clovis spear point was discovered imbedded in the bone of the pelvis. Equally significant were DNA results indicating the individual was of Caucasian racial origin. Consequently, this sensational archaeological discovery stimulated widespread debates concerning the populating of the Western Hemisphere: the migration routes, the eras of the waves of migration, and the peoples involved. In spite of the enormous historical and cultural significance of the Kennewick find, contemporary Native American Indian Tribes (Nez Perce, Umatilla, Yakima, Wannapum, Colville) prevailed in the courts and were awarded the bones for a "dignified" and "sacred" reburial on the Columbia River bank at the discovery location. Whereas this reburial may have been culturally sensitive, it was both dangerous and imprudent. The internment site is only a short distance downriver from one of the most contaminated nuclear repositories in the world. The Hanford Nuclear Reservation has twelve shutdown atomic reactors that were constructed almost seventy years ago and built for the production of plutonium. The facility also encompasses five chemical-processing complexes for the extraction and refining of plutonium. During the past few decades many of the reactors, as well as their single-wall waste storage tanks and ponds, have deteriorated and have been leaking radioactive and toxic-chemical waste into the local aquifer. This contaminated ground water has been seeping ever closer to the banks of the Columbia River and the resting place of Kennewick Man and other associated (yet to be found) artifacts. Without remediative steps the toxic flow will continue past Kennewick to threaten cities such as Portland with a Chernobyl-like tragedy. Consequently, a remediation program was initiated to drain the leaking tanks and ponds so that the toxic wastes could be buried elsewhere and/or transferred to more secure double-shell reservoirs. Unfortunately, hazardous substances adhere to pores and corrosion on the vessel walls after draining. This poses problems when disposing of refuse materials and hardware from the site. It has been experimentally determined that this hazardous surface contamination may be ejected by means of radiation ablation. It was concluded that this is most effectively accomplished with underwater flashlamp irradiation. In this manner the dislodged surface contamination is freed to float in the water and is then captured and concentrated by the filters of the fluid circulation systems. The final phase of the project was assistance in designing a Stonehenge-like monument to celebrate the cleanup of the Hanford Reservation and the removal of the radioactive threat to the final resting place of Kennewick Man ("The Ancient One").

Survey and Testing of Archaeological Resources at Clinton Lake, Kansas, 1978-1979.

DTIC Science & Technology

1980-08-01

Lake area. Some sites appear to be special purpose camps, while others may be more permanently or regularly occupied base camps or villages. The...96 Plate 15. Clovis-like Point Base from 14D0137. ........ 101 Plate 16. Core from Site 14D0140................110 Plate 17...that effort required for testing and evaluation should be based on some measurable parameter in order to protect both parties. A volumetric measure of

Large scale mitochondrial sequencing in Mexican Americans suggests a reappraisal of Native American origins.

PubMed

Kumar, Satish; Bellis, Claire; Zlojutro, Mark; Melton, Phillip E; Blangero, John; Curran, Joanne E

2011-10-07

The Asian origin of Native Americans is largely accepted. However uncertainties persist regarding the source population(s) within Asia, the divergence and arrival time(s) of the founder groups, the number of expansion events, and migration routes into the New World. mtDNA data, presented over the past two decades, have been used to suggest a single-migration model for which the Beringian land mass plays an important role. In our analysis of 568 mitochondrial genomes, the coalescent age estimates of shared roots between Native American and Siberian-Asian lineages, calculated using two different mutation rates, are A4 (27.5 ± 6.8 kya/22.7 ± 7.4 kya), C1 (21.4 ± 2.7 kya/16.4 ± 1.5 kya), C4 (21.0 ± 4.6 kya/20.0 ± 6.4 kya), and D4e1 (24.1 ± 9.0 kya/17.9 ± 10.0 kya). The coalescent age estimates of pan-American haplogroups calculated using the same two mutation rates (A2:19.5 ± 1.3 kya/16.1 ± 1.5 kya, B2:20.8 ± 2.0 kya/18.1 ± 2.4 kya, C1:21.4 ± 2.7 kya/16.4 ± 1.5 kya and D1:17.2 ± 2.0 kya/14.9 ± 2.2 kya) and estimates of population expansions within America (~21-16 kya), support the pre-Clovis occupation of the New World. The phylogeography of sublineages within American haplogroups A2, B2, D1 and the C1b, C1c and C1d subhaplogroups of C1 are complex and largely specific to geographical North, Central and South America. However some sub-branches (B2b, C1b, C1c, C1d and D1f) already existed in American founder haplogroups before expansion into the America. Our results suggest that Native American founders diverged from their Siberian-Asian progenitors sometime during the last glacial maximum (LGM) and expanded into America soon after the LGM peak (~20-16 kya). The phylogeography of haplogroup C1 suggest that this American founder haplogroup differentiated in Siberia-Asia. The situation is less clear for haplogroup B2, however haplogroups A2 and D1 may have differentiated soon after the Native American founders divergence. A moderate population bottle neck in American founder populations just before the expansion most plausibly resulted in few founder types in America. The similar estimates of the diversity indices and Bayesian skyline analysis in North America, Central America and South America suggest almost simultaneous (~ 2.0 ky from South to North America) colonization of these geographical regions with rapid population expansion differentiating into more or less regional branches across the pan-American haplogroups.

Large scale mitochondrial sequencing in Mexican Americans suggests a reappraisal of Native American origins

PubMed Central

2011-01-01

Background The Asian origin of Native Americans is largely accepted. However uncertainties persist regarding the source population(s) within Asia, the divergence and arrival time(s) of the founder groups, the number of expansion events, and migration routes into the New World. mtDNA data, presented over the past two decades, have been used to suggest a single-migration model for which the Beringian land mass plays an important role. Results In our analysis of 568 mitochondrial genomes, the coalescent age estimates of shared roots between Native American and Siberian-Asian lineages, calculated using two different mutation rates, are A4 (27.5 ± 6.8 kya/22.7 ± 7.4 kya), C1 (21.4 ± 2.7 kya/16.4 ± 1.5 kya), C4 (21.0 ± 4.6 kya/20.0 ± 6.4 kya), and D4e1 (24.1 ± 9.0 kya/17.9 ± 10.0 kya). The coalescent age estimates of pan-American haplogroups calculated using the same two mutation rates (A2:19.5 ± 1.3 kya/16.1 ± 1.5 kya, B2:20.8 ± 2.0 kya/18.1 ± 2.4 kya, C1:21.4 ± 2.7 kya/16.4 ± 1.5 kya and D1:17.2 ± 2.0 kya/14.9 ± 2.2 kya) and estimates of population expansions within America (~21-16 kya), support the pre-Clovis occupation of the New World. The phylogeography of sublineages within American haplogroups A2, B2, D1 and the C1b, C1c andC1d subhaplogroups of C1 are complex and largely specific to geographical North, Central and South America. However some sub-branches (B2b, C1b, C1c, C1d and D1f) already existed in American founder haplogroups before expansion into the America. Conclusions Our results suggest that Native American founders diverged from their Siberian-Asian progenitors sometime during the last glacial maximum (LGM) and expanded into America soon after the LGM peak (~20-16 kya). The phylogeography of haplogroup C1 suggest that this American founder haplogroup differentiated in Siberia-Asia. The situation is less clear for haplogroup B2, however haplogroups A2 and D1 may have differentiated soon after the Native American founders divergence. A moderate population bottle neck in American founder populations just before the expansion most plausibly resulted in few founder types in America. The similar estimates of the diversity indices and Bayesian skyline analysis in North America, Central America and South America suggest almost simultaneous (~ 2.0 ky from South to North America) colonization of these geographical regions with rapid population expansion differentiating into more or less regional branches across the pan-American haplogroups. PMID:21978175

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension.

PubMed

Nieuwland, Mante S; Politzer-Ahles, Stephen; Heyselaar, Evelien; Segaert, Katrien; Darley, Emily; Kazanina, Nina; Von Grebmer Zu Wolfsthurn, Sarah; Bartolozzi, Federica; Kogan, Vita; Ito, Aine; Mézière, Diane; Barr, Dale J; Rousselet, Guillaume A; Ferguson, Heather J; Busch-Moreno, Simon; Fu, Xiao; Tuomainen, Jyrki; Kulakova, Eugenia; Husband, E Matthew; Donaldson, David I; Kohút, Zdenko; Rueschemeyer, Shirley-Ann; Huettig, Falk

2018-04-03

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment ('cloze'). In our direct replication study spanning 9 laboratories ( N =334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words. © 2018, Nieuwland et al.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension

PubMed Central

Politzer-Ahles, Stephen; Heyselaar, Evelien; Segaert, Katrien; Darley, Emily; Kazanina, Nina; Von Grebmer Zu Wolfsthurn, Sarah; Bartolozzi, Federica; Kogan, Vita; Ito, Aine; Mézière, Diane; Barr, Dale J; Rousselet, Guillaume A; Ferguson, Heather J; Busch-Moreno, Simon; Fu, Xiao; Tuomainen, Jyrki; Kulakova, Eugenia; Husband, E Matthew; Donaldson, David I; Kohút, Zdenko; Rueschemeyer, Shirley-Ann; Huettig, Falk

2018-01-01

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment (‘cloze’). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words. PMID:29631695

Cannon AFB, Clovis, New Mexico. Revised Uniform Summary of Surface Weather Observations (RUSSWO), Parts A-F

DTIC Science & Technology

1975-06-16

dry -bulb temperature, means and standard d~viatinne nf eirg-hiiih- wM~e-.h,lh (y DD 1473 ~ UNCLASSIFIED SECURIS- CLASSIFICATION OF THIS PAGE(Ifnon...Val. Entoted) 19. Percentqge frequency of distribution tables Dry -bulb temperature versus wet-bulb temperature Cumulative percentage frequency of...ATMOSPHERIC PHENOMENA EXTREME MAX & MIN TEMP PART B PRECIPITATION PSYCHROMETRIC- DRY VS WET BULB SNOWFALL MEAN & STD DEV - ( DRY BULB, WET BULB, & DEW

The Archaeology and History of Lake Ray Roberts. Volume 1. Cultural Resources Survey.

DTIC Science & Technology

1982-03-01

the survey have rendered the information they contain through the recording process and should be determined ineligible for further study. Fifty-five...clay features were actually human hearths ( Heizer and Brooks 1965), and the possibility that the Clovis point was planted ( Heizer 1974). Recent research...15:157-172. Hart, John Fraser 1976 The look of the land. Prentice-Hall, Englewood Cliffs, New Jersey. * 9-5 Heizer , R.F. 1974 Some thoughts on hoaxes

Radiocarbon and DNA evidence for a pre-Columbian introduction of Polynesian chickens to Chile

PubMed Central

Storey, Alice A.; Ramírez, José Miguel; Quiroz, Daniel; Burley, David V.; Addison, David J.; Walter, Richard; Anderson, Atholl J.; Hunt, Terry L.; Athens, J. Stephen; Huynen, Leon; Matisoo-Smith, Elizabeth A.

2007-01-01

Two issues long debated among Pacific and American prehistorians are (i) whether there was a pre-Columbian introduction of chicken (Gallus gallus) to the Americas and (ii) whether Polynesian contact with South America might be identified archaeologically, through the recovery of remains of unquestionable Polynesian origin. We present a radiocarbon date and an ancient DNA sequence from a single chicken bone recovered from the archaeological site of El Arenal-1, on the Arauco Peninsula, Chile. These results not only provide firm evidence for the pre-Columbian introduction of chickens to the Americas, but strongly suggest that it was a Polynesian introduction. PMID:17556540

Radiocarbon and DNA evidence for a pre-Columbian introduction of Polynesian chickens to Chile.

PubMed

Storey, Alice A; Ramírez, José Miguel; Quiroz, Daniel; Burley, David V; Addison, David J; Walter, Richard; Anderson, Atholl J; Hunt, Terry L; Athens, J Stephen; Huynen, Leon; Matisoo-Smith, Elizabeth A

2007-06-19

Two issues long debated among Pacific and American prehistorians are (i) whether there was a pre-Columbian introduction of chicken (Gallus gallus) to the Americas and (ii) whether Polynesian contact with South America might be identified archaeologically, through the recovery of remains of unquestionable Polynesian origin. We present a radiocarbon date and an ancient DNA sequence from a single chicken bone recovered from the archaeological site of El Arenal-1, on the Arauco Peninsula, Chile. These results not only provide firm evidence for the pre-Columbian introduction of chickens to the Americas, but strongly suggest that it was a Polynesian introduction.

Daylight Redirecting Window Film

DTIC Science & Technology

2013-12-01

Fort Bliss , TX; Clovis Vaughn and Andrew Burton at 29 Palms, CA; Doug Taber at Naval Post Graduate School (NPS), Monterey; and Mitch Hailey at Naval...Agarwal and Tim Perry for their immense contribution to this project. Finally, throughout the project, the guidance and counseling of Vern Novstrup at...and control) VA Norfolk Z-133 1 1 1 6 72 48 120 CA 29 Palms 1416 5 7 14 13 108 31 62 RI Newport Hewitt Hall 2 5 9 19 88 24 40 TX Fort Bliss

[The origins of the French neurosurgery].

PubMed

Brunon, J

2016-06-01

Modern French neurosurgery starts at the beginning of the XXth century under the motivation of Joseph Babinski. He submitted his patients to Thierry de Martel who had learned this new specialized area of medicine with H. Cushing in the États-Unis and V. Horsey in Great Britain. His first successfully treated case of an intracranial tumor was published in 1909. But the true founding father was Clovis Vincent, initially a neurologist and collaborator of de Martel, who became the first chairman in 1933 of the neurosurgical department at the Pitié hospital of Paris and the first professor of neurosurgery in 1938. After the Second World War, many departments were created outside of Paris. Neurosurgery was definitively recognized as a specialized area in medicine in 1948. Currently, more than 400 neurosurgeons work in France. Because I had the very great privilege to be present at the birth of this society in 1970 and to still be in contact with some of the second and third generation of French neurosurgeons who led it to its high international recognition, the Chairman of the French Neurosurgical Society asked me to write this short historical vignette. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Commission Review of a Proposal by the State Center Community College District to Establish the Willow-International Community College Center: A Report to the Governor and Legislature in Response to a Request from the Board of Governors of the California Community Colleges. Commission Report 03-05

ERIC Educational Resources Information Center

California Postsecondary Education Commission, 2003

2003-01-01

This report reviews a proposal by the State Center Community College District to establish a State-approved education center in the city of Fresno. The center would be named the Willow-International Community College Center, and it would replace an existing Clovis operational outreach center that is considered by the district to be insufficient…

Recent lidar measurements of stratospheric ozone and temperature within the network for the detection of stratospheric change

NASA Technical Reports Server (NTRS)

Mcgee, Thomas J.; Ferrare, Richard; Butler, James J.; Frost, Robert L.; Gross, Michael; Margitan, James

1991-01-01

The Goddard mobile lidar was deployed at Cannon Air Force Base near Clovis, New Mexico during the Spring of 1990. Measurements of stratospheric ozone and temperature were made over a period of six weeks. Data from the lidar system is compared with data from a balloon-borne, ultraviolet instrument launched from nearby Ft. Sumner, New Mexico. Along with several improvements to this instrument which are now underway, a second lidar dedicated to temperature and aerosol measurements is now being developed.

Wandering tales: evolutionary origins of mental time travel and language

PubMed Central

Corballis, Michael C.

2013-01-01

A central component of mind wandering is mental time travel, the calling to mind of remembered past events and of imagined future ones. Mental time travel may also be critical to the evolution of language, which enables us to communicate about the non-present, sharing memories, plans, and ideas. Mental time travel is indexed in humans by hippocampal activity, and studies also suggest that the hippocampus in rats is active when the animals replay or pre play activity in a spatial environment, such as a maze. Mental time travel may have ancient origins, contrary to the view that it is unique to humans. Since mental time travel is also thought to underlie language, these findings suggest that language evolved gradually from pre-existing cognitive capacities, contrary to the view of Chomsky and others that language and symbolic thought emerged abruptly, in a single step, within the past 100,000 years. PMID:23908641

Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis.

PubMed

Pigati, Jeffrey S; Latorre, Claudio; Rech, Jason A; Betancourt, Julio L; Martínez, Katherine E; Budahn, James R

2012-05-08

The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various "impact markers" were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event.

Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis

PubMed Central

Pigati, Jeffrey S.; Latorre, Claudio; Rech, Jason A.; Betancourt, Julio L.; Martínez, Katherine E.; Budahn, James R.

2012-01-01

The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various “impact markers” were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event. PMID:22529347

Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis

USGS Publications Warehouse

Pigati, Jeffrey S.; Latorre, Claudio; Rech, Jason A.; Betancourt, Julio L.; Martinez, Katherine E.; Budahn, James R.

2012-01-01

The Younger Dryas impact hypothesis contends that an extraterrestrial object exploded over North America at 12.9 ka, initiating the Younger Dryas cold event, the extinction of many North American megafauna, and the demise of the Clovis archeological culture. Although the exact nature and location of the proposed impact or explosion remain unclear, alleged evidence for the fallout comes from multiple sites across North America and a site in Belgium. At 6 of the 10 original sites (excluding the Carolina Bays), elevated concentrations of various "impact markers" were found in association with black mats that date to the onset of the Younger Dryas. Black mats are common features in paleowetland deposits and typically represent shallow marsh environments. In this study, we investigated black mats ranging in age from approximately 6 to more than 40 ka in the southwestern United States and the Atacama Desert of northern Chile. At 10 of 13 sites, we found elevated concentrations of iridium in bulk and magnetic sediments, magnetic spherules, and/or titanomagnetite grains within or at the base of black mats, regardless of their age or location, suggesting that elevated concentrations of these markers arise from processes common to wetland systems, and not a catastrophic extraterrestrial impact event.

Age profiles in elephant and mammoth bone assemblages

NASA Astrophysics Data System (ADS)

Haynes, Gary

1985-11-01

Age profiles of modern African elephant ( Loxodonta africana) populations are significantly affected by drought conditions that cause local die-offs. Subadult animals die in proportions that may be nearly twice what is recorded in live populations. Such biasing of death sample age profiles might also have occurred during late Pleistocene die-offs of Mammuthus. This comparative study of modern and fossil proboscidean age structures supports a tentative interpretation that late Pleistocene extinction of Mammuthus (at least in the southwestern United States) resulted from severe drought conditions, at which Clovis hunters were witnesses, but not necessarily frequent participants.

The Shine-Dalgarno sequence of riboswitch-regulated single mRNAs shows ligand-dependent accessibility bursts

NASA Astrophysics Data System (ADS)

Rinaldi, Arlie J.; Lund, Paul E.; Blanco, Mario R.; Walter, Nils G.

2016-01-01

In response to intracellular signals in Gram-negative bacteria, translational riboswitches--commonly embedded in messenger RNAs (mRNAs)--regulate gene expression through inhibition of translation initiation. It is generally thought that this regulation originates from occlusion of the Shine-Dalgarno (SD) sequence upon ligand binding; however, little direct evidence exists. Here we develop Single Molecule Kinetic Analysis of RNA Transient Structure (SiM-KARTS) to investigate the ligand-dependent accessibility of the SD sequence of an mRNA hosting the 7-aminomethyl-7-deazaguanine (preQ1)-sensing riboswitch. Spike train analysis reveals that individual mRNA molecules alternate between two conformational states, distinguished by `bursts' of probe binding associated with increased SD sequence accessibility. Addition of preQ1 decreases the lifetime of the SD's high-accessibility (bursting) state and prolongs the time between bursts. In addition, ligand-jump experiments reveal imperfect riboswitching of single mRNA molecules. Such complex ligand sensing by individual mRNA molecules rationalizes the nuanced ligand response observed during bulk mRNA translation.

Extracting Models in Single Molecule Experiments

NASA Astrophysics Data System (ADS)

Presse, Steve

2013-03-01

Single molecule experiments can now monitor the journey of a protein from its assembly near a ribosome to its proteolytic demise. Ideally all single molecule data should be self-explanatory. However data originating from single molecule experiments is particularly challenging to interpret on account of fluctuations and noise at such small scales. Realistically, basic understanding comes from models carefully extracted from the noisy data. Statistical mechanics, and maximum entropy in particular, provide a powerful framework for accomplishing this task in a principled fashion. Here I will discuss our work in extracting conformational memory from single molecule force spectroscopy experiments on large biomolecules. One clear advantage of this method is that we let the data tend towards the correct model, we do not fit the data. I will show that the dynamical model of the single molecule dynamics which emerges from this analysis is often more textured and complex than could otherwise come from fitting the data to a pre-conceived model.

Single Molecule Analysis of Replicated DNA Reveals the Usage of Multiple KSHV Genome Regions for Latent Replication

PubMed Central

Verma, Subhash C.; Lu, Jie; Cai, Qiliang; Kosiyatrakul, Settapong; McDowell, Maria E.; Schildkraut, Carl L.; Robertson, Erle S.

2011-01-01

Kaposi's sarcoma associated herpesvirus (KSHV), an etiologic agent of Kaposi's sarcoma, Body Cavity Based Lymphoma and Multicentric Castleman's Disease, establishes lifelong latency in infected cells. The KSHV genome tethers to the host chromosome with the help of a latency associated nuclear antigen (LANA). Additionally, LANA supports replication of the latent origins within the terminal repeats by recruiting cellular factors. Our previous studies identified and characterized another latent origin, which supported the replication of plasmids ex-vivo without LANA expression in trans. Therefore identification of an additional origin site prompted us to analyze the entire KSHV genome for replication initiation sites using single molecule analysis of replicated DNA (SMARD). Our results showed that replication of DNA can initiate throughout the KSHV genome and the usage of these regions is not conserved in two different KSHV strains investigated. SMARD also showed that the utilization of multiple replication initiation sites occurs across large regions of the genome rather than a specified sequence. The replication origin of the terminal repeats showed only a slight preference for their usage indicating that LANA dependent origin at the terminal repeats (TR) plays only a limited role in genome duplication. Furthermore, we performed chromatin immunoprecipitation for ORC2 and MCM3, which are part of the pre-replication initiation complex to determine the genomic sites where these proteins accumulate, to provide further characterization of potential replication initiation sites on the KSHV genome. The ChIP data confirmed accumulation of these pre-RC proteins at multiple genomic sites in a cell cycle dependent manner. Our data also show that both the frequency and the sites of replication initiation vary within the two KSHV genomes studied here, suggesting that initiation of replication is likely to be affected by the genomic context rather than the DNA sequences. PMID:22072974

Possible Evidence for Iron Sulfates, Iron Sulfides, and Elemental Sulfur at Gusev Crater, Mars, from Mer, Crism, and Analog Data

NASA Technical Reports Server (NTRS)

Morris, R. V.; Ming, D. W.; Yen, A.; Arvidson, R. E.; Gruener, J.; Humm, D.; Klingelhoefer, G.; Murchie, S.; Schroeder, C.; Seelos, F., IV;

Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions

NASA Astrophysics Data System (ADS)

Gibard, Clémentine; Bhowmik, Subhendu; Karki, Megha; Kim, Eun-Kyong; Krishnamurthy, Ramanarayanan

2018-02-01

Prebiotic phosphorylation of (pre)biological substrates under aqueous conditions is a critical step in the origins of life. Previous investigations have had limited success and/or require unique environments that are incompatible with subsequent generation of the corresponding oligomers or higher-order structures. Here, we demonstrate that diamidophosphate (DAP)—a plausible prebiotic agent produced from trimetaphosphate—efficiently (amido)phosphorylates a wide variety of (pre)biological building blocks (nucleosides/tides, amino acids and lipid precursors) under aqueous (solution/paste) conditions, without the need for a condensing agent. Significantly, higher-order structures (oligonucleotides, peptides and liposomes) are formed under the same phosphorylation reaction conditions. This plausible prebiotic phosphorylation process under similar reaction conditions could enable the systems chemistry of the three classes of (pre)biologically relevant molecules and their oligomers, in a single-pot aqueous environment.

Phosphorylation, oligomerization and self-assembly in water under potential prebiotic conditions

NASA Astrophysics Data System (ADS)

Gibard, Clémentine; Bhowmik, Subhendu; Karki, Megha; Kim, Eun-Kyong; Krishnamurthy, Ramanarayanan

2017-11-01

Prebiotic phosphorylation of (pre)biological substrates under aqueous conditions is a critical step in the origins of life. Previous investigations have had limited success and/or require unique environments that are incompatible with subsequent generation of the corresponding oligomers or higher-order structures. Here, we demonstrate that diamidophosphate (DAP)-a plausible prebiotic agent produced from trimetaphosphate - efficiently (amido)phosphorylates a wide variety of (pre)biological building blocks (nucleosides/tides, amino acids and lipid precursors) under aqueous (solution/paste) conditions, without the need for a condensing agent. Significantly, higher-order structures (oligonucleotides, peptides and liposomes) are formed under the same phosphorylation reaction conditions. This plausible prebiotic phosphorylation process under similar reaction conditions could enable the systems chemistry of the three classes of (pre)biologically relevant molecules and their oligomers, in a single-pot aqueous environment.

The sdA problem - I. Physical properties

NASA Astrophysics Data System (ADS)

Pelisoli, Ingrid; Kepler, S. O.; Koester, D.

2018-04-01

The so-called sdA stars are defined by having H-rich spectra and surface gravities similar to hot subdwarf stars, but effective temperature below the zero-age horizontal branch. Their evolutionary history is an enigma: their surface gravity is too high for main-sequence stars, but too low for single evolution white dwarfs. They are most likely byproducts of binary evolution, including blue-stragglers, extremely-low mass white dwarf stars (ELMs) and their precursors (pre-ELMs). A small number of ELMs with similar properties to sdAs is known. Other possibilities include metal-poor A/F dwarfs, second generation stars, or even stars accreted from dwarf galaxies. In this work, we analyse colours, proper motions, and spacial velocities of a sample of sdAs from the Sloan Digital Sky Survey to assess their nature and evolutionary origin. We define a probability of belonging to the main sequence and a probability of being a (pre-)ELM based on these properties. We find that 7 per cent of the sdAs are more likely to be (pre-)ELMs than main-sequence stars. However, the spacial velocity distribution suggests that over 35 per cent of them cannot be explained as single metal-poor A/F stars.

Rocks of the Columbia Hills

USGS Publications Warehouse

Squyres, S. W.; Arvidson, R. E.; Blaney, D.L.; Clark, B. C.; Crumpler, L.; Farrand, W. H.; Gorevan, S.; Herkenhoff, K. E.; Hurowitz, J.; Kusack, A.; McSween, H.Y.; Ming, D. W.; Morris, R.V.; Ruff, S.W.; Wang, A.; Yen, A.

2006-01-01

The Mars Exploration Rover Spirit has identified five distinct rock types in the Columbia Hills of Gusev crater. Clovis Class rock is a poorly sorted clastic rock that has undergone substantial aqueous alteration. We interpret it to be aqueously altered ejecta deposits formed by impacts into basaltic materials. Wishstone Class rock is also a poorly sorted clastic rock that has a distinctive chemical composition that is high in Ti and P and low in Cr. Wishstone Class rock may be pyroclastic or impact in origin. Peace Class rock is a sedimentary material composed of ultramafic sand grains cemented by significant quantities of Mg- and Ca-sulfates. Peace Class rock may have formed when water briefly saturated the ultramafic sands and evaporated to allow precipitation of the sulfates. Watchtower Class rocks are similar chemically to Wishstone Class rocks and have undergone widely varying degrees of near-isochemical aqueous alteration. They may also be ejecta deposits, formed by impacts into Wishstone-rich materials and altered by small amounts of water. Backstay Class rocks are basalt/trachybasalt lavas that were emplaced in the Columbia Hills after the other rock classes were, either as impact ejecta or by localized volcanic activity. The geologic record preserved in the rocks of the Columbia Hills reveals a period very early in Martian history in which volcanic materials were widespread, impact was a dominant process, and water was commonly present. Copyright 2006 by the American Geophysical Union.

The Rocks of the Columbia Hills

NASA Technical Reports Server (NTRS)

Squyres, Steven W.; Arvidson, Raymond E.; Blaney, Diana L.; Clark, Benton C.; Crumpler, Larry; Farrand, William H.; Gorevan, Stephen; Herkenhoff, Kenneth; Hurowitz, Joel; Kusack, Alastair;

The architecture of the DNA replication origin recognition complex in Saccharomyces cerevisiae

PubMed Central

Chen, Zhiqiang; Speck, Christian; Wendel, Patricia; Tang, Chunyan; Stillman, Bruce; Li, Huilin

2008-01-01

The origin recognition complex (ORC) is conserved in all eukaryotes. The six proteins of the Saccharomyces cerevisiae ORC that form a stable complex bind to origins of DNA replication and recruit prereplicative complex (pre-RC) proteins, one of which is Cdc6. To further understand the function of ORC we recently determined by single-particle reconstruction of electron micrographs a low-resolution, 3D structure of S. cerevisiae ORC and the ORC–Cdc6 complex. In this article, the spatial arrangement of the ORC subunits within the ORC structure is described. In one approach, a maltose binding protein (MBP) was systematically fused to the N or the C termini of the five largest ORC subunits, one subunit at a time, generating 10 MBP-fused ORCs, and the MBP density was localized in the averaged, 2D EM images of the MBP-fused ORC particles. Determining the Orc1–5 structure and comparing it with the native ORC structure localized the Orc6 subunit near Orc2 and Orc3. Finally, subunit–subunit interactions were determined by immunoprecipitation of ORC subunits synthesized in vitro. Based on the derived ORC architecture and existing structures of archaeal Orc1–DNA structures, we propose a model for ORC and suggest how ORC interacts with origin DNA and Cdc6. The studies provide a basis for understanding the overall structure of the pre-RC. PMID:18647841

Nucleosome occupancy as a novel chromatin parameter for replication origin functions

PubMed Central

Rodriguez, Jairo; Lee, Laura; Lynch, Bryony; Tsukiyama, Toshio

2017-01-01

Eukaryotic DNA replication initiates from multiple discrete sites in the genome, termed origins of replication (origins). Prior to S phase, multiple origins are poised to initiate replication by recruitment of the pre-replicative complex (pre-RC). For proper replication to occur, origin activation must be tightly regulated. At the population level, each origin has a distinct firing time and frequency of activation within S phase. Many studies have shown that chromatin can strongly influence initiation of DNA replication. However, the chromatin parameters that affect properties of origins have not been thoroughly established. We found that nucleosome occupancy in G1 varies greatly around origins across the S. cerevisiae genome, and nucleosome occupancy around origins significantly correlates with the activation time and efficiency of origins, as well as pre-RC formation. We further demonstrate that nucleosome occupancy around origins in G1 is established during transition from G2/M to G1 in a pre-RC-dependent manner. Importantly, the diminished cell-cycle changes in nucleosome occupancy around origins in the orc1-161 mutant are associated with an abnormal global origin usage profile, suggesting that proper establishment of nucleosome occupancy around origins is a critical step for regulation of global origin activities. Our work thus establishes nucleosome occupancy as a novel and key chromatin parameter for proper origin regulation. PMID:27895110

Hallervorden-Spatz disease: historical case presentation in the spotlight of nosological evolution.

PubMed

Van Craenenbroeck, Amaryllis; Gebruers, Marilien; Martin, Jean-Jacques; Cras, Patrick

2010-11-15

Baron Dr. Ludo van Bogaert (1897-1989) authored more than 700 publications, gave countless lectures at Belgian and foreign universities and at international congresses, and trained more than 300 specialists from all over the world in the Bunge Institute. He filmed many of his patients suffering from movement disorders. Hallervorden-Spatz disease (HSD) was first described in 1922. The recognition of this well-defined syndrome was followed by several case reports published and in 1936, a new case was reported by Ludo van Bogaert and Clovis Vincent. To the best of our knowledge, this case report can be considered as the first filmed case of HSD. © 2010 Movement Disorder Society.

Genome-wide chromatin footprinting reveals changes in replication origin architecture induced by pre-RC assembly

PubMed Central

MacAlpine, Heather K.; Lubelsky, Yoav; Hartemink, Alexander J.

2015-01-01

Start sites of DNA replication are marked by the origin recognition complex (ORC), which coordinates Mcm2–7 helicase loading to form the prereplicative complex (pre-RC). Although pre-RC assembly is well characterized in vitro, the process is poorly understood within the local chromatin environment surrounding replication origins. To reveal how the chromatin architecture modulates origin selection and activation, we “footprinted” nucleosomes, transcription factors, and replication proteins at multiple points during the Saccharomyces cerevisiae cell cycle. Our nucleotide-resolution protein occupancy profiles resolved a precise ORC-dependent footprint at 269 origins in G2. A separate class of inefficient origins exhibited protein occupancy only in G1, suggesting that stable ORC chromatin association in G2 is a determinant of origin efficiency. G1 nucleosome remodeling concomitant with pre-RC assembly expanded the origin nucleosome-free region and enhanced activation efficiency. Finally, the local chromatin environment restricts the loading of the Mcm2–7 double hexamer either upstream of or downstream from the ARS consensus sequence (ACS). PMID:25593310

Are pre-crater mounds gas-inflated?

NASA Astrophysics Data System (ADS)

Leibman, Marina; Kizyakov, Alexandr; Khomutov, Artem; Dvornikov, Yury; Babkina, Elena; Arefiev, Stanislav; Khairullin, Rustam

2017-04-01

Gas-emission craters (GEC) on Yamal peninsula, which occupied minds of researches for the last couple of years since first discovered in 2014, appeared to form on the place of specifically shaped mounds. There was a number of hypotheses involving pingo as an origin of these mounds. This arouse an interest in mapping pingo thus marking the areas of GEC formation risk. Our field research allows us to suggest that remote-sensing-based mapping of pingo may result in mix up of mounds of various origin. Thus, we started with classification of the mounds based on remote-sensing, field observations and survey from helicopter. Then we compared indicators of mounds of various classes to the properties of pre-crater mounds to conclude on their origin. Summarizing field experience, there are three main mound types on Yamal. (1) Outliers (remnant hills), separated from the main geomorphic landform by erosion. Often these mounds comprise polygonal blocks, kind of "baydzherakh". Their indicators are asymmetry (short gentle slope towards the main landform, and steep slope often descending into a small pond of thermokarst-nivation origin), often quadrangle or conic shape, and large size. (2) Pingo, appear within the khasyrei (drain lake basin); often are characterized by open cracks resulting from expansion of polygonal network formed when re-freezing of lake talik prior to pingo formation; old pingo may bear traces of collapse on the top, with depression which differs from the GEC by absence of parapet. (3) Frost-heave mounds (excluding pingo) may form on deep active layer, reducing due to moss-peat formation and forming ice lenses from an active layer water, usually they appear in the drainage hollows, valley bottoms, drain-lake basins periphery. These features are smaller than the first two types of mounds. Their tops as a rule are well vegetated. We were unable to find a single or a set of indicators unequivocally defining any specific mound type, thus indicators of pre-crater mounds are still debatable. Our hypothesis initially does not involve pingo origin of pre-crater mounds for several reasons, among which were the initial depth (70 m) and width (18 m) of the crater void, frozen walls and bottom, no traces of sub-lake talik, an important control for pingo formation, and more. Pre-crater mounds are closer to frost-heave mounds in size (4-7 m high and 30-60 m in diameter). Yet frost-heave mounds like palsa or lithalsa have segregated ice lenses closer to the surface, total thickness of these lenses is equal to the height of the mound. Pre-crater mounds have at least 20 m of tabular ground ice in the section that has no manifestation in the mound height or diameter. All above-mentioned leads to the conclusion that pre-crater mounds form because of gas inflation rather than regular frost heave process involving moisture migration towards the freezing front. This research is supported by Russian Science Foundation Grant 16-17-10203.

14. Photocopy of pre1956 photograph. Original in library of John ...

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

14. Photocopy of pre-1956 photograph. Original in library of John S. Lehmann Building, Missouri Botanical Garden. CEILING, SHOWING ORIGINAL SKYLIGHT NOW PLASTERED OVER - Missouri Botanical Garden, Museum, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

22. Photocopy of pre1891 photograph. Original in library of Lehmann ...

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

22. Photocopy of pre-1891 photograph. Original in library of Lehmann Building, Missouri Botanical Garden. HOUSE ON ORIGINAL SITE, SHOWING SOUTH WING STUCCOED - Missouri Botanical Garden, Henry Shaw Townhouse, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

Laser ablation of Dbx1 neurons in the pre-Bötzinger complex stops inspiratory rhythm and impairs output in neonatal mice

PubMed Central

Wang, Xueying; Hayes, John A; Revill, Ann L; Song, Hanbing; Kottick, Andrew; Vann, Nikolas C; LaMar, M Drew; Picardo, Maria Cristina D; Akins, Victoria T; Funk, Gregory D; Del Negro, Christopher A

2014-01-01

To understand the neural origins of rhythmic behavior one must characterize the central pattern generator circuit and quantify the population size needed to sustain functionality. Breathing-related interneurons of the brainstem pre-Bötzinger complex (preBötC) that putatively comprise the core respiratory rhythm generator in mammals are derived from Dbx1-expressing precursors. Here, we show that selective photonic destruction of Dbx1 preBötC neurons in neonatal mouse slices impairs respiratory rhythm but surprisingly also the magnitude of motor output; respiratory hypoglossal nerve discharge decreased and its frequency steadily diminished until rhythm stopped irreversibly after 85±20 (mean ± SEM) cellular ablations, which corresponds to ∼15% of the estimated population. These results demonstrate that a single canonical interneuron class generates respiratory rhythm and contributes in a premotor capacity, whereas these functions are normally attributed to discrete populations. We also establish quantitative cellular parameters that govern network viability, which may have ramifications for respiratory pathology in disease states. DOI: http://dx.doi.org/10.7554/eLife.03427.001 PMID:25027440

Analysis of proviral integration in human mammary epithelial cell lines immortalized by retroviral infection with a temperature-sensitive SV40 T-antigen construct.

PubMed

Stamps, A C; Davies, S C; Burman, J; O'Hare, M J

1994-06-15

A panel of eight conditionally immortal lines derived by infection of human breast epithelial cells with an amphotropic retrovirus transducing a ts mutant of SV40 large T-antigen was analyzed with respect to individual retroviral integration patterns. Each line contained multiple integration sites which were clonal and stable over extended passage. Similar integration patterns were observed between individual lines arising separately from the same stock of pre-immortal cells, suggesting a common progenitor. Retroviral integration analysis of pre-immortal cells at different stages of pre-crisis growth showed changes indicative of a progressive transition from polyclonality to clonality as the cells approached crisis. Each of the immortal lines contained a sub-set of the integration sites of their pre-immortal progenitors, with individual combinations and copy numbers of sites. Since all the cell lines appeared to originate from single foci in separate flasks, it is likely that each set arose from a common clone of pre-immortal cells as the result of separate genetic events. There was no evidence from this analysis to suggest that specific integration sites played any part either in the selection of pre-crisis clones or in the subsequent establishment of immortal lines.

Moessbauer Mineralogy of Rock, Soil, and Dust at Gusev Crater, Mars: Spirit's Journey through Weakly Altered Olivine Basalt on the Plains and Pervasively Altered Basalt in the Columbia Hills

NASA Technical Reports Server (NTRS)

Morris, R. V.; Klingelhoefer, G.; Schroeder, C.; Rodionov, D. S.; Yen, A.; Ming, D. W.; deSouza, P. A., Jr.; Fleischer, I.; Wdowiak, T.; Gellert, R.;

21. Photocopy of pre1891 photograph. Original in library of Lehmann ...

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

21. Photocopy of pre-1891 photograph. Original in library of Lehmann Building, Missouri Botanical Garden. EAST AND NORTH WALLS OF HOUSE ON ORIGINAL SITE AT SEVENTH AND LOCUST STREETS - Missouri Botanical Garden, Henry Shaw Townhouse, 2345 Tower Grove Avenue, Saint Louis, Independent City, MO

Gulf Coast geopressured-geothermal program summary report compilation. Volume 2-A: Resource description, program history, wells tested, university and company based research, site restoration

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

John, C.J.; Maciasz, G.; Harder, B.J.

The US Department of Energy established a geopressured-geothermal energy program in the mid 1970`s as one response to America`s need to develop alternate energy resources in view of the increasing dependence on imported fossil fuel energy. This program continued for 17 years and approximately two hundred million dollars were expended for various types of research and well testing to thoroughly investigate this alternative energy source. This volume describes the following studies: Geopressured-geothermal resource description; Resource origin and sediment type; Gulf Coast resource extent; Resource estimates; Project history; Authorizing legislation; Program objectives; Perceived constraints; Program activities and structure; Well testing; Programmore » management; Program cost summary; Funding history; Resource characterization; Wells of opportunity; Edna Delcambre No. 1 well; Edna Delcambre well recompletion; Fairfax Foster Sutter No. 2 well; Beulah Simon No. 2 well; P.E. Girouard No. 1 well; Prairie Canal No. 1 well; Crown Zellerbach No. 2 well; Alice C. Plantation No. 2 well; Tenneco Fee N No. 1 well; Pauline Kraft No. 1 well; Saldana well No. 2; G.M. Koelemay well No. 1; Willis Hulin No. 1 well; Investigations of other wells of opportunity; Clovis A. Kennedy No. 1 well; Watkins-Miller No. 1 well; Lucien J. Richard et al No. 1 well; and the C and K-Frank A. Godchaux, III, well No. 1.« less

Human footprints in Central Mexico older than 40,000 years

NASA Astrophysics Data System (ADS)

González, Silvia; Huddart, David; Bennett, Matthew R.; González-Huesca, Alberto

2006-02-01

The timing, route and origin of the first colonization to the Americas remains one of the most contentious topics in human evolution. A number of migration routes have been suggested and there are different views as to the antiquity of the earliest human occupation. Some believe that settlement happened as early as 30 ka BP, but most of the currently accepted early sites in North America date to the latest Pleistocene, related to the expansion of the Clovis culture, while the oldest directly radiocarbon dated human remains are 11.5 ka BP. In this context new evidence is presented in this paper, in the form of human footprints preserved in indurated volcanic ash, to suggest that Central Mexico was inhabited as early as over 40 ka BP. Human and animal footprints have been found within the upper bedding surfaces of the Xalnene volcanic ash layer that outcrops in the Valsequillo Basin, south of Puebla, Mexico. This ash layer was produced by a subaqueous monogenetic volcano erupting within a palaeo-lake, dammed by lava within the Valsequillo Basin during the Pleistocene. The footprints were formed during low stands in lake level along the former shorelines and indicate the presence of humans, deer, canids, big felids, and probably camels and bovids. The footprints were buried by ash and lake sediments as lake levels rose and transgressed across the site. The ash has been dated to at least 40 ka BP by OSL dating of incorporated, baked lake sediments.

Evidence for a Massive Extraterrestrial Airburst over North America 12.9 ka Ago

NASA Astrophysics Data System (ADS)

Firestone, R. B.; West, A.; Revay, Z.; Belgya, T.; Smith, A.; Que Hee, S. S.

2007-05-01

A carbon-rich black layer commonly referred to as a black mat, with a basal age of approximately 12.9 ka, has been identified at over 50 sites across North America1. The age of the base of the black mat coincides with the abrupt onset of Younger Dryas cooling and megafaunal extinctions in North America. In situ bones of extinct mammals, including mammoths, mastodons, ground sloths, horses, camels, many smaller mammals and birds, and Clovis tool assemblages occur below the black mat but not within or above it. In this paper, we provide evidence for an ejecta layer at the base of the black mat from an extraterrestrial impact event 12.9 ka ago. We have investigated nine terminal Clovis-age sites in North America and a comparable site in Lommel, Belgium that are all marked by a thin, discrete layer containing varying peak abundances of (1) magnetic grains/microspherules containing iridium concentrations up to 117 ppb, (2) charcoal, (3) soot, (4) vesicular carbon spherules, (5) glass-like carbon, and (6) fullerenes enriched in 3He. This layer also extends throughout the rims of at least fifteen Carolina Bays, unique, elliptical, oriented lakes and wetlands scattered across the Atlantic Coastal Plain whose major axes point towards the Great Lakes and Canada. Microspherules, highly enriched in titanium, were found only in or near the YD boundary (YDB) layer with greatest deposition rates (35 per cm2) occurring near the Great Lakes. Magnetic grains also peak in the YDB with maximum deposition near the Great Lakes (30 mg/cm2). Magnetic grains near the Great Lakes are enriched in magnetite (4 mg/cm2) and silicates (23 mg/cm2) but contain less ilmenite/rutile (1 mg/cm2) than distant sites where ilmentite/rutile deposition ranges up to 18 mg/cm2. Analysis of the ilmenite/rutile-rich magnetic grains and microspherules indicates that they contain considerable water, up to 28 at.% hydrogen, and have TIO2/FeO, TIO2/Zr, Al2O3/FeO+MgO, CaO/Al2O3, REE/chondrite, K/Th, FeO/MnO ratios and SIO2, Na2O, K2O, Cr2O3, Ni, Co, Ir, Th, U, and other trace element abundances that are inconsistent with all terrestrial and extraterrestrial sources except for Lunar Procellarum KREEP terrain (PKT). We propose that the YDB layer is the ejecta layer from an airburst over the Laurentide Ice Sheet that deposited local, low-speed terrestrial material near the airburst site and KREEP-like, high-speed projectile material farther away, leaving little or no permanent crater. The associated blast wave and thermal pulse would have contributed to the megafaunal extinctions and destabilized the Laurentide Ice Sheet, loading the atmosphere with dust, soot, NOx, and water vapor and triggered the YD cooling. 1 Haynes, C. V., Jr. in Murray Springs: a Clovis site with multiple activity areas in the San Pedro Valley, Arizona. C. V. Haynes, Jr. and Bruce B. Huckell, eds. Tucson: Univ. of Arizona Press, in press, 2007.

[A case of diprosopus in the cat].

PubMed

Aharon, D C; Wouda, W; van Weelden, E

1986-06-15

A case of diprosopus in a spontaneously delivered live-born kitten is reported. All facial components were completely duplicated. Fusion of the skulls had occurred in the temporal region; a single ear was present at the site of fusion. Additional defects were a cleft lip in one face and cleft palates in both faces. The cerebral hemispheres and arterior portions of the brain stem were completely duplicated, whereas the cerebellum and caudal brain stem were partially duplicated. The pathogenesis and aetiology are discussed. It is believed that disprosopus originates during the (pre)gastrulation stage of embryonic development, either by coalescence of two embryonic fields following a double process of gastrulation or by bifurcation of the axial mesoderm during a single gastrulation.

The complete mitochondrial genome of an 11,450-year-old aurochsen (Bos primigenius) from Central Italy.

PubMed

Lari, Martina; Rizzi, Ermanno; Mona, Stefano; Corti, Giorgio; Catalano, Giulio; Chen, Kefei; Vernesi, Cristiano; Larson, Greger; Boscato, Paolo; De Bellis, Gianluca; Cooper, Alan; Caramelli, David; Bertorelle, Giorgio

2011-01-31

Bos primigenius, the aurochs, is the wild ancestor of modern cattle breeds and was formerly widespread across Eurasia and northern Africa. After a progressive decline, the species became extinct in 1627. The origin of modern taurine breeds in Europe is debated. Archaeological and early genetic evidence point to a single Near Eastern origin and a subsequent spread during the diffusion of herding and farming. More recent genetic data are instead compatible with local domestication events or at least some level of local introgression from the aurochs. Here we present the analysis of the complete mitochondrial genome of a pre-Neolithic Italian aurochs. In this study, we applied a combined strategy employing both multiplex PCR amplifications and 454 pyrosequencing technology to sequence the complete mitochondrial genome of an 11,450-year-old aurochs specimen from Central Italy. Phylogenetic analysis of the aurochs mtDNA genome supports the conclusions from previous studies of short mtDNA fragments--namely that Italian aurochsen were genetically very similar to modern cattle breeds, but highly divergent from the North-Central European aurochsen. Complete mitochondrial genome sequences are now available for several modern cattle and two pre-Neolithic mtDNA genomes from very different geographic areas. These data suggest that previously identified sub-groups within the widespread modern cattle mitochondrial T clade are polyphyletic, and they support the hypothesis that modern European breeds have multiple geographic origins.

A photoelectrochemical platform for the capture and release of rare single cells.

PubMed

Parker, Stephen G; Yang, Ying; Ciampi, Simone; Gupta, Bakul; Kimpton, Kathleen; Mansfeld, Friederike M; Kavallaris, Maria; Gaus, Katharina; Gooding, J Justin

2018-06-12

For many normal and aberrant cell behaviours, it is important to understand the origin of cellular heterogeneity. Although powerful methods for studying cell heterogeneity have emerged, they are more suitable for common rather than rare cells. Exploring the heterogeneity of rare single cells is challenging because these rare cells must be first pre-concentrated and undergo analysis prior to classification and expansion. Here, a versatile capture & release platform consisting of an antibody-modified and electrochemically cleavable semiconducting silicon surface for release of individual cells of interest is presented. The captured cells can be interrogated microscopically and tested for drug responsiveness prior to release and recovery. The capture & release strategy was applied to identify rare tumour cells from whole blood, monitor the uptake of, and response to, doxorubicin and subsequently select cells for single-cell gene expression based on their response to the doxorubicin.

DNA sequence templates adjacent nucleosome and ORC sites at gene amplification origins in Drosophila

PubMed Central

Liu, Jun; Zimmer, Kurt; Rusch, Douglas B.; Paranjape, Neha; Podicheti, Ram; Tang, Haixu; Calvi, Brian R.

2015-01-01

Eukaryotic origins of DNA replication are bound by the origin recognition complex (ORC), which scaffolds assembly of a pre-replicative complex (pre-RC) that is then activated to initiate replication. Both pre-RC assembly and activation are strongly influenced by developmental changes to the epigenome, but molecular mechanisms remain incompletely defined. We have been examining the activation of origins responsible for developmental gene amplification in Drosophila. At a specific time in oogenesis, somatic follicle cells transition from genomic replication to a locus-specific replication from six amplicon origins. Previous evidence indicated that these amplicon origins are activated by nucleosome acetylation, but how this affects origin chromatin is unknown. Here, we examine nucleosome position in follicle cells using micrococcal nuclease digestion with Ilumina sequencing. The results indicate that ORC binding sites and other essential origin sequences are nucleosome-depleted regions (NDRs). Nucleosome position at the amplicons was highly similar among developmental stages during which ORC is or is not bound, indicating that being an NDR is not sufficient to specify ORC binding. Importantly, the data suggest that nucleosomes and ORC have opposite preferences for DNA sequence and structure. We propose that nucleosome hyperacetylation promotes pre-RC assembly onto adjacent DNA sequences that are disfavored by nucleosomes but favored by ORC. PMID:26227968

RNomics in Archaea reveals a further link between splicing of archaeal introns and rRNA processing

PubMed Central

Tang, Thean Hock; Rozhdestvensky, Timofey S.; d’Orval, Béatrice Clouet; Bortolin, Marie-Line; Huber, Harald; Charpentier, Bruno; Branlant, Christiane; Bachellerie, Jean-Pierre; Brosius, Jürgen; Hüttenhofer, Alexander

2002-01-01

The bulge–helix–bulge (BHB) motif recognised by the archaeal splicing endonuclease is also found in the long processing stems of archaeal rRNA precursors in which it is cleaved to generate pre-16S and pre-23S rRNAs. We show that in two species, Archaeoglobus fulgidus and Sulfolobus solfataricus, representatives from the two major archaeal kingdoms Euryarchaeota and Crenarchaeota, respectively, the pre-rRNA spacers cleaved at the BHB motifs surrounding pre-16S and pre-23S rRNAs subsequently become ligated. In addition, we present evidence that this is accompanied by circularisation of ribosomal pre-16S and pre-23S rRNAs in both species. These data reveal a further link between intron splicing and pre-rRNA processing in Archaea, which might reflect a common evolutionary origin of the two processes. One spliced RNA species designated 16S-D RNA, resulting from religation at the BHB motif of 16S pre-rRNA, is a highly abundant and stable RNA which folds into a three-stem structure interrupted by two single-stranded regions as assessed by chemical probing. It spans a region of the pre-rRNA 5′ external transcribed spacer exhibiting a highly conserved folding pattern in Archaea. Surprisingly, 16S-D RNA contains structural motifs found in archaeal C/D box small RNAs and binds to the L7Ae protein, a core component of archaeal C/D box RNPs. This supports the notion that it might have an important but still unknown role in pre-rRNA biogenesis or might even target RNA molecules other than rRNA. PMID:11842103

Differential Chromatin Structure Encompassing Replication Origins in Transformed and Normal Cells

PubMed Central

Di Paola, Domenic; Rampakakis, Emmanouil; Chan, Man Kid

2012-01-01

This study examines the chromatin structure encompassing replication origins in transformed and normal cells. Analysis of the global levels of histone H3 acetylated at K9&14 (open chromatin) and histone H3 trimethylated at K9 (closed chromatin) revealed a higher ratio of open to closed chromatin in the transformed cells. Also, the trithorax and polycomb group proteins, Brg-1 and Bmi-1, respectively, were overexpressed and more abundantly bound to chromatin in the transformed cells. Quantitative comparative analyses of episomal and in situ chromosomal replication origin activity as well as chromatin immunoprecipitation (ChIP) assays, using specific antibodies targeting members of the pre-replication complex (pre-RC) as well as open/closed chromatin markers encompassing both episomal and chromosomal origins, revealed that episomal origins had similar levels of in vivo activity, nascent DNA abundance, pre-RC protein association, and elevated open chromatin structure at the origin in both cell types. In contrast, the chromosomal origins corresponding to 20mer1, 20mer2, and c-myc displayed a 2- to 3-fold higher activity and pre-RC protein abundance as well as higher ratios of open to closed chromatin and of Brg-1 to Bmi-1 in the transformed cells, whereas the origin associated with the housekeeping lamin B2 gene exhibited similar levels of activity, pre-RC protein abundance, and higher ratios of open to closed chromatin and of Brg-1 to Bmi-1 in both cell types. Nucleosomal positioning analysis, using an MNase-Southern blot assay, showed that all the origin regions examined were situated within regions of inconsistently positioned nucleosomes, with the nucleosomes being spaced farther apart from each other prior to the onset of S phase in both cell types. Overall, the results indicate that cellular transformation is associated with differential epigenetic regulation, whereby chromatin structure is more open, rendering replication origins more accessible to initiator proteins, thus allowing increased origin activity. PMID:23050047

Structure and origin of Australian ring and dome features with reference to the search for asteroid impact events

NASA Astrophysics Data System (ADS)

Glikson, Andrew

2018-01-01

Ring, dome and crater features on the Australian continent and shelf include (A) 38 structures of confirmed or probable asteroid and meteorite impact origin and (B) numerous buried and exposed ring, dome and crater features of undefined origin. A large number of the latter include structural and geophysical elements consistent with impact structures, pending test by field investigations and/or drilling. This paper documents and briefly describes 43 ring and dome features with the aim of appraising their similarities and differences from those of impact structures. Discrimination between impact structures and igneous plugs, volcanic caldera and salt domes require field work and/or drilling. Where crater-like morphological patterns intersect pre-existing linear structural features and contain central morphological highs and unique thrust and fault patterns an impact connection needs to tested in the field. Hints of potential buried impact structures may be furnished by single or multi-ring TMI patterns, circular TMI quiet zones, corresponding gravity patterns, low velocity and non-reflective seismic zones.

Random Mutagenesis, Clonal Events, and Embryonic or Somatic Origin Determine the mtDNA Variant Type and Load in Human Pluripotent Stem Cells.

PubMed

Zambelli, Filippo; Mertens, Joke; Dziedzicka, Dominika; Sterckx, Johan; Markouli, Christina; Keller, Alexander; Tropel, Philippe; Jung, Laura; Viville, Stephane; Van de Velde, Hilde; Geens, Mieke; Seneca, Sara; Sermon, Karen; Spits, Claudia

2018-06-07

In this study, we deep-sequenced the mtDNA of human embryonic and induced pluripotent stem cells (hESCs and hiPSCs) and their source cells and found that the majority of variants pre-existed in the cells used to establish the lines. Early-passage hESCs carried few and low-load heteroplasmic variants, similar to those identified in oocytes and inner cell masses. The number and heteroplasmic loads of these variants increased with prolonged cell culture. The study of 120 individual cells of early- and late-passage hESCs revealed a significant diversity in mtDNA heteroplasmic variants at the single-cell level and that the variants that increase during time in culture are always passenger to the appearance of chromosomal abnormalities. We found that early-passage hiPSCs carry much higher loads of mtDNA variants than hESCs, which single-fibroblast sequencing proved pre-existed in the source cells. Finally, we show that these variants are stably transmitted during short-term differentiation. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Adapting the academic motivation scale for use in pre-tertiary mathematics classrooms

NASA Astrophysics Data System (ADS)

Lim, Siew Yee; Chapman, Elaine

2015-09-01

The Academic Motivation Scale ( ams) is a comprehensive and widely used instrument for assessing motivation based on the self-determination theory. Currently, no such comprehensive instrument exists to assess the different domains of motivation (stipulated by the self-determination theory) in mathematics education at the pre-tertiary level (grades 11 and 12) in Asia. This study adapted the ams for this use and assessed the properties of the adapted instrument with 1610 students from Singapore. Exploratory and confirmatory factor analyses indicated a five-factor structure for the modified instrument (the three original ams intrinsic subscales collapsed into a single factor). Additionally, the modified instrument exhibited good internal consistency (mean α = .88), and satisfactory test-retest reliability over a 1-month interval (mean r xx = .73). The validity of the modified ams was further demonstrated through correlational analyses among scores on its subscales, and with scores on other instruments measuring mathematics attitudes, anxiety and achievement.

Origins of the temperature dependence of hammerhead ribozyme catalysis.

PubMed Central

Peracchi, A

1999-01-01

The difficulties in interpreting the temperature dependence of protein enzyme reactions are well recognized. Here, the hammerhead ribozyme cleavage was investigated under single-turnover conditions between 0 and 60 degrees C as a model for RNA-catalyzed reactions. Under the adopted conditions, the chemical step appears to be rate-limiting. However, the observed rate of cleavage is affected by pre-catalytic equilibria involving deprotonation of an essential group and binding of at least one low-affinity Mg2+ion. Thus, the apparent entropy and enthalpy of activation include contributions from the temperature dependence of these equilibria, precluding a simple physical interpretation of the observed activation parameters. Similar pre-catalytic equilibria likely contribute to the observed activation parameters for ribozyme reactions in general. The Arrhenius plot for the hammerhead reaction is substantially curved over the temperature range considered, which suggests the occurrence of a conformational change of the ribozyme ground state around physiological temperatures. PMID:10390528

The Younger Dryas impact hypothesis: A requiem

NASA Astrophysics Data System (ADS)

Pinter, Nicholas; Scott, Andrew C.; Daulton, Tyrone L.; Podoll, Andrew; Koeberl, Christian; Anderson, R. Scott; Ishman, Scott E.

2011-06-01

The Younger Dryas (YD) impact hypothesis is a recent theory that suggests that a cometary or meteoritic body or bodies hit and/or exploded over North America 12,900 years ago, causing the YD climate episode, extinction of Pleistocene megafauna, demise of the Clovis archeological culture, and a range of other effects. Since gaining widespread attention in 2007, substantial research has focused on testing the 12 main signatures presented as evidence of a catastrophic extraterrestrial event 12,900 years ago. Here we present a review of the impact hypothesis, including its evolution and current variants, and of efforts to test and corroborate the hypothesis. The physical evidence interpreted as signatures of an impact event can be separated into two groups. The first group consists of evidence that has been largely rejected by the scientific community and is no longer in widespread discussion, including: particle tracks in archeological chert; magnetic nodules in Pleistocene bones; impact origin of the Carolina Bays; and elevated concentrations of radioactivity, iridium, and fullerenes enriched in 3He. The second group consists of evidence that has been active in recent research and discussions: carbon spheres and elongates, magnetic grains and magnetic spherules, byproducts of catastrophic wildfire, and nanodiamonds. Over time, however, these signatures have also seen contrary evidence rather than support. Recent studies have shown that carbon spheres and elongates do not represent extraterrestrial carbon nor impact-induced megafires, but are indistinguishable from fungal sclerotia and arthropod fecal material that are a small but common component of many terrestrial deposits. Magnetic grains and spherules are heterogeneously distributed in sediments, but reported measurements of unique peaks in concentrations at the YD onset have yet to be reproduced. The magnetic grains are certainly just iron-rich detrital grains, whereas reported YD magnetic spherules are consistent with the diffuse, non-catastrophic input of micrometeorite ablation fallout, probably augmented by anthropogenic and other terrestrial spherular grains. Results here also show considerable subjectivity in the reported sampling methods that may explain the purported YD spherule concentration peaks. Fire is a pervasive earth-surface process, and reanalyses of the original YD sites and of coeval records show episodic fire on the landscape through the latest Pleistocene, with no unique fire event at the onset of the YD. Lastly, with YD impact proponents increasingly retreating to nanodiamonds (cubic, hexagonal [lonsdaleite], and the proposed n-diamond) as evidence of impact, those data have been called into question. The presence of lonsdaleite was reported as proof of impact-related shock processes, but the evidence presented was inconsistent with lonsdaleite and consistent instead with polycrystalline aggregates of graphene and graphane mixtures that are ubiquitous in carbon forms isolated from sediments ranging from modern to pre-YD age. Important questions remain regarding the origins and distribution of other diamond forms (e.g., cubic nanodiamonds). In summary, none of the original YD impact signatures have been subsequently corroborated by independent tests. Of the 12 original lines of evidence, seven have so far proven to be non-reproducible. The remaining signatures instead seem to represent either (1) non-catastrophic mechanisms, and/or (2) terrestrial rather than extraterrestrial or impact-related sources. In all of these cases, sparse but ubiquitous materials seem to have been misreported and misinterpreted as singular peaks at the onset of the YD. Throughout the arc of this hypothesis, recognized and expected impact markers were not found, leading to proposed YD impactors and impact processes that were novel, self-contradictory, rapidly changing, and sometimes defying the laws of physics. The YD impact hypothesis provides a cautionary tale for researchers, the scientific community, the press, and the broader public.

The Complete Mitochondrial Genome of an 11,450-year-old Aurochsen (Bos primigenius) from Central Italy

PubMed Central

2011-01-01

Background Bos primigenius, the aurochs, is the wild ancestor of modern cattle breeds and was formerly widespread across Eurasia and northern Africa. After a progressive decline, the species became extinct in 1627. The origin of modern taurine breeds in Europe is debated. Archaeological and early genetic evidence point to a single Near Eastern origin and a subsequent spread during the diffusion of herding and farming. More recent genetic data are instead compatible with local domestication events or at least some level of local introgression from the aurochs. Here we present the analysis of the complete mitochondrial genome of a pre-Neolithic Italian aurochs. Results In this study, we applied a combined strategy employing both multiplex PCR amplifications and 454 pyrosequencing technology to sequence the complete mitochondrial genome of an 11,450-year-old aurochs specimen from Central Italy. Phylogenetic analysis of the aurochs mtDNA genome supports the conclusions from previous studies of short mtDNA fragments - namely that Italian aurochsen were genetically very similar to modern cattle breeds, but highly divergent from the North-Central European aurochsen. Conclusions Complete mitochondrial genome sequences are now available for several modern cattle and two pre-Neolithic mtDNA genomes from very different geographic areas. These data suggest that previously identified sub-groups within the widespread modern cattle mitochondrial T clade are polyphyletic, and they support the hypothesis that modern European breeds have multiple geographic origins. PMID:21281509

A Study into the Design of a Pre-Laboratory Software Resource in Effectively Assisting in the Chemistry Proficiency of Students of Chinese Origin Undertaking Post 16 Chemistry in the UK

ERIC Educational Resources Information Center

O'Sullivan, Saskia Katarina Emily; Harrison, Timothy Guy

2016-01-01

This qualitative study indicates that Chinese origin students completing their pre-university education in a British school have particular difficulties related to sociocultural change, pedagogical differences, affective aspects, cognitive demand and language learning. These are discussed. The use of a pre-laboratory software resource to support…

Stability, chromatin association and functional activity of mammalian pre-replication complex proteins during the cell cycle

PubMed Central

Okuno, Yukiko; McNairn, Adrian J.; den Elzen, Nicole; Pines, Jonathon; Gilbert, David M.

2001-01-01

We have examined the behavior of pre-replication complex (pre-RC) proteins in relation to key cell cycle transitions in Chinese Hamster Ovary (CHO) cells. ORC1, ORC4 and Cdc6 were stable (T1/2 >2 h) and associated with a chromatin-containing fraction throughout the cell cycle. Green fluorescent protein-tagged ORC1 associated with chromatin throughout mitosis in living cells and co-localized with ORC4 in metaphase spreads. Association of Mcm proteins with chromatin took place during telophase, ∼30 min after the destruction of geminin and cyclins A and B, and was coincident with the licensing of chromatin to replicate in geminin-supplemented Xenopus egg extracts. Neither Mcm recruitment nor licensing required protein synthesis throughout mitosis. Moreover, licensing could be uncoupled from origin specification in geminin-supplemented extracts; site-specific initiation within the dihydrofolate reductase locus required nuclei from cells that had passed through the origin decision point (ODP). These results demonstrate that mammalian pre-RC assembly takes place during telophase, mediated by post-translational modifications of pre-existing proteins, and is not sufficient to select specific origin sites. A subsequent, as yet undefined, step selects which pre-RCs will function as replication origins. PMID:11483529

Condensing Raman spectrum for single-cell phenotype analysis.

PubMed

Sun, Shiwei; Wang, Xuetao; Gao, Xin; Ren, Lihui; Su, Xiaoquan; Bu, Dongbo; Ning, Kang

2015-01-01

In recent years, high throughput and non-invasive Raman spectrometry technique has matured as an effective approach to identification of individual cells by species, even in complex, mixed populations. Raman profiling is an appealing optical microscopic method to achieve this. To fully utilize Raman proling for single-cell analysis, an extensive understanding of Raman spectra is necessary to answer questions such as which filtering methodologies are effective for pre-processing of Raman spectra, what strains can be distinguished by Raman spectra, and what features serve best as Raman-based biomarkers for single-cells, etc. In this work, we have proposed an approach called rDisc to discretize the original Raman spectrum into only a few (usually less than 20) representative peaks (Raman shifts). The approach has advantages in removing noises, and condensing the original spectrum. In particular, effective signal processing procedures were designed to eliminate noise, utilising wavelet transform denoising, baseline correction, and signal normalization. In the discretizing process, representative peaks were selected to signicantly decrease the Raman data size. More importantly, the selected peaks are chosen as suitable to serve as key biological markers to differentiate species and other cellular features. Additionally, the classication performance of discretized spectra was found to be comparable to full spectrum having more than 1000 Raman shifts. Overall, the discretized spectrum needs about 5storage space of a full spectrum and the processing speed is considerably faster. This makes rDisc clearly superior to other methods for single-cell classication.

Pre-Columbian origins of Native American dog breeds, with only limited replacement by European dogs, confirmed by mtDNA analysis.

PubMed

van Asch, Barbara; Zhang, Ai-bing; Oskarsson, Mattias C R; Klütsch, Cornelya F C; Amorim, António; Savolainen, Peter

2013-09-07

Dogs were present in pre-Columbian America, presumably brought by early human migrants from Asia. Studies of free-ranging village/street dogs have indicated almost total replacement of these original dogs by European dogs, but the extent to which Arctic, North and South American breeds are descendants of the original population remains to be assessed. Using a comprehensive phylogeographic analysis, we traced the origin of the mitochondrial DNA lineages for Inuit, Eskimo and Greenland dogs, Alaskan Malamute, Chihuahua, xoloitzcuintli and perro sín pelo del Peru, by comparing to extensive samples of East Asian (n = 984) and European dogs (n = 639), and previously published pre-Columbian sequences. Evidence for a pre-Columbian origin was found for all these breeds, except Alaskan Malamute for which results were ambigous. No European influence was indicated for the Arctic breeds Inuit, Eskimo and Greenland dog, and North/South American breeds had at most 30% European female lineages, suggesting marginal replacement by European dogs. Genetic continuity through time was shown by the sharing of a unique haplotype between the Mexican breed Chihuahua and ancient Mexican samples. We also analysed free-ranging dogs, confirming limited pre-Columbian ancestry overall, but also identifying pockets of remaining populations with high proportion of indigenous ancestry, and we provide the first DNA-based evidence that the Carolina dog, a free-ranging population in the USA, may have an ancient Asian origin.

Inhibitive effects of anti-oxidative vitamins on mannitol-induced apoptosis of vascular endothelial cells.

PubMed

Pan, Kai-yu; Shen, Mei-ping; Ye, Zhi-hong; Dai, Xiao-na; Shang, Shi-qiang

2006-10-01

Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins. Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was performed with normal saline (group B), vitamin C (group C) and vitamin E (group D). Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline (sample B), vitamin C (sample C) and vitamin E (sample D). Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression. In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only, and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes. Vitamin C can protect vascular endothelial cells from mannitol-induced injury.

SCF(FBXW7α) modulates the intra-S-phase DNA-damage checkpoint by regulating Polo like kinase-1 stability.

PubMed

Giráldez, Servando; Herrero-Ruiz, Joaquín; Mora-Santos, Mar; Japón, Miguel Á; Tortolero, Maria; Romero, Francisco

2014-06-30

The intra-S-checkpoint is essential to control cell progression through S phase under normal conditions and in response to replication stress. When DNA lesions are detected, replication fork progression is blocked allowing time for repair to avoid genomic instability and the risk of cancer. DNA replication initiates at many origins of replication in eukaryotic cells, where a series of proteins form pre-replicative complexes (pre-RCs) that are activated to become pre-initiation complexes and ensure a single round of replication in each cell cycle. PLK1 plays an important role in the regulation of DNA replication, contributing to the regulation of pre-RCs formation by phosphorylating several proteins, under both normal and stress conditions. Here we report that PLK1 is ubiquitinated and degraded by SCFFBXW7α/proteasome. Moreover, we identified a new Cdc4 phosphodegron in PLK1, conserved from yeast to humans, whose mutation prevents PLK1 destruction. We established that endogenous SCFFBXW7α degrades PLK1 in the G1 and S phases of an unperturbed cell cycle and in S phase following UV irradiation. Furthermore, we showed that FBXW7α overexpression or UV irradiation prevented the loading of proteins onto chromatin to form pre-RCs and, accordingly, reduced cell proliferation. We conclude that PLK1 degradation mediated by SCFFBXW7α modulates the intra-S-phase checkpoint.

SCFFBXW7α modulates the intra-S-phase DNA-damage checkpoint by regulating Polo like kinase-1 stability

PubMed Central

Giráldez, Servando; Herrero-Ruiz, Joaquín; Mora-Santos, Mar; Japón, Miguel Á.; Tortolero, Maria; Romero, Francisco

2014-01-01

The intra-S-checkpoint is essential to control cell progression through S phase under normal conditions and in response to replication stress. When DNA lesions are detected, replication fork progression is blocked allowing time for repair to avoid genomic instability and the risk of cancer. DNA replication initiates at many origins of replication in eukaryotic cells, where a series of proteins form pre-replicative complexes (pre-RCs) that are activated to become pre-initiation complexes and ensure a single round of replication in each cell cycle. PLK1 plays an important role in the regulation of DNA replication, contributing to the regulation of pre-RCs formation by phosphorylating several proteins, under both normal and stress conditions. Here we report that PLK1 is ubiquitinated and degraded by SCFFBXW7α/proteasome. Moreover, we identified a new Cdc4 phosphodegron in PLK1, conserved from yeast to humans, whose mutation prevents PLK1 destruction. We established that endogenous SCFFBXW7α degrades PLK1 in the G1 and S phases of an unperturbed cell cycle and in S phase following UV irradiation. Furthermore, we showed that FBXW7α overexpression or UV irradiation prevented the loading of proteins onto chromatin to form pre-RCs and, accordingly, reduced cell proliferation. We conclude that PLK1 degradation mediated by SCFFBXW7α modulates the intra-S-phase checkpoint. PMID:24970797

Pleistocene glaciers, lakes, and floods in north-central Washington State

USGS Publications Warehouse

Waitt, Richard B.; Haugerud, Ralph A.; Kelsey, Harvey M.

2017-01-01

The Methow, Chelan, Wenatchee, and other terrane blocks accreted in late Mesozoic to Eocene times. Methow valley is excavated in an exotic terrane of folded Mesozoic sedimentary and volcanic rocks faulted between crystalline blocks. Repeated floods of Columbia River Basalt about 16 Ma drowned a backarc basin to the southeast. Cirques, aretes, and U-shaped hanging troughs brand the Methow, Skagit, and Chelan headwaters. The Late Wisconsin Cordilleran icesheet beveled the alpine topography and deposited drift. Cordilleran ice flowed into the heads of Methow tributaries and overflowed from Skagit tributaries to greatly augment Chelan trough's glacier. Joined Okanogan and Methow ice flowed down Columbia valley and up lower Chelan trough. This tongue met the icesheet tongue flowing southeast down Chelan valley. Successively lower ice-marginal channels and kame terraces show that the icesheet withered away largely by downwasting. Immense late Wisconsin floods from glacial Lake Missoula occasionally swept the Chelan-Vantage reach of Columbia valley by different routes. The earliest debacles, nearly 19,000 cal yr BP (by radiocarbon methods), raged 335 m deep down the Columbia and built high Pangborn bar at Wenatchee. As Cordilleran ice blocked the northwest of Columbia valley, several giant floods descended Moses Coulee and backflooded up the Columbia. As advancing ice then blocked Moses Coulee, Grand Coulee to Quincy basin became the westmost floodway. From Quincy basin many Missoula floods backflowed 50 km upvalley past Wenatchee 18,000 to 15,500 years ago. Receding ice dammed glacial Lake Columbia centuries more--till it burst about 15,000 years ago. After Glacier Peak ashfall about 13,600 years ago, smaller great flood(s) swept down the Columbia from glacial Lake Kootenay in British Columbia. A cache of huge fluted Clovis points had been laid atop Pangborn bar (East Wenatchee) after the Glacier Peak ashfall. Clovis people came two and a half millennia after the last small Missoula flood, two millennia after the glacial Lake Columbia flood. This timing by radiocarbon methods is under review by newer exposure dating--10Be, 26Al, and 36Cl methods.

18 CFR 4.38 - Consultation requirements.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Consultation... original license commences first stage pre-filing consultation on or after July 23, 2005 it shall file a... potential applicant for an original license that commences pre-filing consultation on or after July 23, 2005...

18 CFR 4.38 - Consultation requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Consultation... original license commences first stage pre-filing consultation on or after July 23, 2005 it shall file a... potential applicant for an original license that commences pre-filing consultation on or after July 23, 2005...

18 CFR 4.38 - Consultation requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Consultation... original license commences first stage pre-filing consultation on or after July 23, 2005 it shall file a... potential applicant for an original license that commences pre-filing consultation on or after July 23, 2005...

18 CFR 4.38 - Consultation requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Consultation... original license commences first stage pre-filing consultation on or after July 23, 2005 it shall file a... potential applicant for an original license that commences pre-filing consultation on or after July 23, 2005...

18 CFR 4.38 - Consultation requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Consultation... original license commences first stage pre-filing consultation on or after July 23, 2005 it shall file a... potential applicant for an original license that commences pre-filing consultation on or after July 23, 2005...

Investigation of modification design of the fan stage in axial compressor

NASA Astrophysics Data System (ADS)

Zhou, Xun; Yan, Peigang; Han, Wanjin

2010-04-01

The S2 flow path design method of the transonic compressor is used to design the one stage fan in order to replace the original designed blade cascade which has two-stage transonic fan rotors. In the modification design, the camber line is parameterized by a quartic polynomial curve and the thickness distribution of the blade profile is controlled by the double-thrice polynomial. Therefore, the inlet flow has been pre-compressed and the location and intensity of the shock wave at supersonic area have been controlled in order to let the new blade profiles have better aerodynamic performance. The computational results show that the new single stage fan rotor increases the efficiency by two percent at the design condition and the total pressure ratio is slightly higher than that of the original design. At the same time, it also meets the mass flow rate and the geometrical size requirements for the modification design.

I know I've seen you before: Distinguishing recent-single-exposure-based familiarity from pre-existing familiarity

PubMed Central

Gimbel, Sarah I.; Brewer, James B.; Maril, Anat

2018-01-01

This study examines how individuals differentiate recent-single-exposure-based familiarity from pre-existing familiarity. If these are two distinct cognitive processes, are they supported by the same neural bases? This study examines how recent-single-exposure-based familiarity and multiple-previous-exposure-based familiarity are supported and represented in the brain using functional MRI. In a novel approach, we first behaviorally show that subjects can divide retrieval of items in pre-existing memory into judgments of recollection and familiarity. Then, using functional magnetic resonance imaging, we examine the differences in blood oxygen level dependent activity and regional connectivity during judgments of recent-single-exposure-based and pre-existing familiarity. Judgments of these two types of familiarity showed distinct regions of activation in a whole-brain analysis, in medial temporal lobe (MTL) substructures, and in MTL substructure functional-correlations with other brain regions. Specifically, within the MTL, perirhinal cortex showed increased activation during recent-single-exposure-based familiarity while parahippocampal cortex showed increased activation during judgments of pre-existing familiarity. We find that recent-single-exposure-based and pre-existing familiarity are represented as distinct neural processes in the brain; this is supported by differing patterns of brain activation and regional correlations. This spatially distinct regional brain involvement suggests that the two separate experiences of familiarity, recent-exposure-based familiarity and pre-existing familiarity, may be cognitively distinct. PMID:28073651

Correction: Gan, L.; Denecke, B. Profiling Pre-MicroRNA and Mature MicroRNA Expressions Using a Single Microarray and Avoiding Separate Sample Preparation. Microarrays 2013, 2, 24-33.

PubMed

Gan, Lin; Denecke, Bernd

2013-06-24

It came to our attention that a paper has recently been published concerning one of the GEO datasets (GSE34413) we cited in our published paper [1]. The original reference (reference 27) cited for this dataset leads to a paper about a similar study from the same research group [2]. In order to provide readers with exact citation information, we would like to update reference 27 in our previous paper to the new published paper concerning GSE34413 [3]. The authors apologize for this inconvenience. [...].

Continuous bioluminescent monitoring of cytoplasmic ATP in single isolated rat hepatocytes during metabolic poisoning.

PubMed Central

Koop, A; Cobbold, P H

1993-01-01

We have devised a technique for monitoring cytoplasmic ATP continuously in single hepatocytes. Single isolated rat hepatocytes were injected with the ATP-dependent luminescent protein firefly luciferase, and then superfused with 45 microM luciferin in air-equilibrated medium. Signals of approx. 10-200 photoelectron counts per second could be recorded from individual healthy cells for up to 3 h. The response of the luminescent signal to chemical hypoxia (2-5 mM CN- and 5-10 mM 2-deoxyglucose) was monitored. We found a great cell-to-cell variability in the time course of the ATP decline in response to CN-, 2-deoxyglucose or to their combination; the time for the signal to fall to 10% of the original (corresponding to approx. 100 microM ATP) ranged from approx. 20 to 75 min. This resistance of the cytoplasmic ATP concentration to depletion after blockade of oxidative phosphorylation and glycolysis could be abolished by pretreatment of the cells with etomoxir, which blocks mitochondrial beta-oxidation. Etomoxir alone had no effect on the luciferase signal, but etomoxir-pre-treated cells showed a prompt fall in the luciferase signal starting within 1-2 min of application of cyanide and 2-deoxyglucose and falling to 10% of the original signal in approx. 6-10 min. The technique allows cytoplasmic ATP changes to be monitored in single hepatocytes at concentrations of 1 mM or lower, but more precise calibration of the signal will require correction for the effects of cytoplasmic pH changes. PMID:8216212

I know I've seen you before: Distinguishing recent-single-exposure-based familiarity from pre-existing familiarity.

PubMed

Gimbel, Sarah I; Brewer, James B; Maril, Anat

2017-03-01

This study examines how individuals differentiate recent-single-exposure-based familiarity from pre-existing familiarity. If these are two distinct cognitive processes, are they supported by the same neural bases? This study examines how recent-single-exposure-based familiarity and multiple-previous-exposure-based familiarity are supported and represented in the brain using functional MRI. In a novel approach, we first behaviorally show that subjects can divide retrieval of items in pre-existing memory into judgments of recollection and familiarity. Then, using functional magnetic resonance imaging, we examine the differences in blood oxygen level dependent activity and regional connectivity during judgments of recent-single-exposure-based and pre-existing familiarity. Judgments of these two types of familiarity showed distinct regions of activation in a whole-brain analysis, in medial temporal lobe (MTL) substructures, and in MTL substructure functional-correlations with other brain regions. Specifically, within the MTL, perirhinal cortex showed increased activation during recent-single-exposure-based familiarity while parahippocampal cortex showed increased activation during judgments of pre-existing familiarity. We find that recent-single-exposure-based and pre-existing familiarity are represented as distinct neural processes in the brain; this is supported by differing patterns of brain activation and regional correlations. This spatially distinct regional brain involvement suggests that the two separate experiences of familiarity, recent-exposure-based familiarity and pre-existing familiarity, may be cognitively distinct. Copyright © 2017 Elsevier B.V. All rights reserved.

A tale of two mechanisms. Strain-softening versus strain-hardening in single crystals under small stressed volumes

DOE PAGES

Bei, Hongbin; Xia, Yuzhi; Barabash, Rozaliya; ...

2015-08-10

Pre-straining defect-free single crystals will introduce heterogeneous dislocation nucleation sources that reduce the measured strength from the theoretical value, while pre-straining bulk samples will lead to strain hardening. Their competition is investigated by nanoindentation pop-in tests on variously pre-strained Mo single crystals with several indenter radii (~micrometer). Pre-straining primarily shifts deformation mechanism from homogeneous dislocation nucleation to a stochastic behavior, while strain hardening plays a secondary role, as summarized in a master plot of pop-in strength versus normalized indenter radius.

Ultrastructural analyses of somatic embryo initiation, development and polarity establishment from mesophyll cells of Dactylis glomerata

NASA Technical Reports Server (NTRS)

Vasilenko, A.; McDaniel, J. K.; Conger, B. V.

2000-01-01

Somatic embryos initiate and develop directly from single mesophyll cells in in vitro-cultured leaf segments of orchardgrass (Dactylis glomerata L.). Embryogenic cells establish themselves in the predivision stage by formation of thicker cell walls and dense cytoplasm. Electron microscopy observations for embryos ranging from the pre-cell-division stage to 20-cell proembryos confirm previous light microscopy studies showing a single cell origin. They also confirm that the first division is predominantly periclinal and that this division plane is important in establishing embryo polarity and in determining the embryo axis. If the first division is anticlinal or if divisions are in random planes after the first division, divisions may not continue to produce an embryo. This result may produce an embryogenic cell mass, callus formation, or no structure at all. Grant numbers: NAGW-3141, NAG10-0221.

Can Propensity Score Analysis Approximate Randomized Experiments Using Pretest and Demographic Information in Pre-K Intervention Research?

PubMed

Dong, Nianbo; Lipsey, Mark W

2017-01-01

It is unclear whether propensity score analysis (PSA) based on pretest and demographic covariates will meet the ignorability assumption for replicating the results of randomized experiments. This study applies within-study comparisons to assess whether pre-Kindergarten (pre-K) treatment effects on achievement outcomes estimated using PSA based on a pretest and demographic covariates can approximate those found in a randomized experiment. Data-Four studies with samples of pre-K children each provided data on two math achievement outcome measures with baseline pretests and child demographic variables that included race, gender, age, language spoken at home, and mother's highest education. Research Design and Data Analysis-A randomized study of a pre-K math curriculum provided benchmark estimates of effects on achievement measures. Comparison samples from other pre-K studies were then substituted for the original randomized control and the effects were reestimated using PSA. The correspondence was evaluated using multiple criteria. The effect estimates using PSA were in the same direction as the benchmark estimates, had similar but not identical statistical significance, and did not differ from the benchmarks at statistically significant levels. However, the magnitude of the effect sizes differed and displayed both absolute and relative bias larger than required to show statistical equivalence with formal tests, but those results were not definitive because of the limited statistical power. We conclude that treatment effect estimates based on a single pretest and demographic covariates in PSA correspond to those from a randomized experiment on the most general criteria for equivalence.

The gene and the genon concept: a functional and information-theoretic analysis

PubMed Central

Scherrer, Klaus; Jost, Jürgen

2007-01-01

‘Gene' has become a vague and ill-defined concept. To set the stage for mathematical analysis of gene storage and expression, we return to the original concept of the gene as a function encoded in the genome, basis of genetic analysis, that is a polypeptide or other functional product. The additional information needed to express a gene is contained within each mRNA as an ensemble of signals, added to or superimposed onto the coding sequence. To designate this programme, we introduce the term ‘genon'. Individual genons are contained in the pre-mRNA forming a pre-genon. A genomic domain contains a proto-genon, with the signals of transcription activation in addition to the pre-genon in the transcripts. Some contain several mRNAs and hence genons, to be singled out by RNA processing and differential splicing. The programme in the genon in cis is implemented by corresponding factors of protein or RNA nature contained in the transgenon of the cell or organism. The gene, the cis programme contained in the individual domain and transcript, and the trans programme of factors, can be analysed by information theory. PMID:17353929

Simultaneous data pre-processing and SVM classification model selection based on a parallel genetic algorithm applied to spectroscopic data of olive oils.

PubMed

Devos, Olivier; Downey, Gerard; Duponchel, Ludovic

2014-04-01

Classification is an important task in chemometrics. For several years now, support vector machines (SVMs) have proven to be powerful for infrared spectral data classification. However such methods require optimisation of parameters in order to control the risk of overfitting and the complexity of the boundary. Furthermore, it is established that the prediction ability of classification models can be improved using pre-processing in order to remove unwanted variance in the spectra. In this paper we propose a new methodology based on genetic algorithm (GA) for the simultaneous optimisation of SVM parameters and pre-processing (GENOPT-SVM). The method has been tested for the discrimination of the geographical origin of Italian olive oil (Ligurian and non-Ligurian) on the basis of near infrared (NIR) or mid infrared (FTIR) spectra. Different classification models (PLS-DA, SVM with mean centre data, GENOPT-SVM) have been tested and statistically compared using McNemar's statistical test. For the two datasets, SVM with optimised pre-processing give models with higher accuracy than the one obtained with PLS-DA on pre-processed data. In the case of the NIR dataset, most of this accuracy improvement (86.3% compared with 82.8% for PLS-DA) occurred using only a single pre-processing step. For the FTIR dataset, three optimised pre-processing steps are required to obtain SVM model with significant accuracy improvement (82.2%) compared to the one obtained with PLS-DA (78.6%). Furthermore, this study demonstrates that even SVM models have to be developed on the basis of well-corrected spectral data in order to obtain higher classification rates. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Effect of Phosphoric Acid Pre-etching Times on Bonding Performance and Surface Free Energy with Single-step Self-etch Adhesives.

PubMed

Tsujimoto, A; Barkmeier, W W; Takamizawa, T; Latta, M A; Miyazaki, M

2016-01-01

The purpose of this study was to evaluate the effect of phosphoric acid pre-etching times on shear bond strength (SBS) and surface free energy (SFE) with single-step self-etch adhesives. The three single-step self-etch adhesives used were: 1) Scotchbond Universal Adhesive (3M ESPE), 2) Clearfil tri-S Bond (Kuraray Noritake Dental), and 3) G-Bond Plus (GC). Two no pre-etching groups, 1) untreated enamel and 2) enamel surfaces after ultrasonic cleaning with distilled water for 30 seconds to remove the smear layer, were prepared. There were four pre-etching groups: 1) enamel surfaces were pre-etched with phosphoric acid (Etchant, 3M ESPE) for 3 seconds, 2) enamel surfaces were pre-etched for 5 seconds, 3) enamel surfaces were pre-etched for 10 seconds, and 4) enamel surfaces were pre-etched for 15 seconds. Resin composite was bonded to the treated enamel surface to determine SBS. The SFEs of treated enamel surfaces were determined by measuring the contact angles of three test liquids. Scanning electron microscopy was used to examine the enamel surfaces and enamel-adhesive interface. The specimens with phosphoric acid pre-etching showed significantly higher SBS and SFEs than the specimens without phosphoric acid pre-etching regardless of the adhesive system used. SBS and SFEs did not increase for phosphoric acid pre-etching times over 3 seconds. There were no significant differences in SBS and SFEs between the specimens with and without a smear layer. The data suggest that phosphoric acid pre-etching of ground enamel improves the bonding performance of single-step self-etch adhesives, but these bonding properties do not increase for phosphoric acid pre-etching times over 3 seconds.

HIDING IN THE SHADOWS: SEARCHING FOR PLANETS IN PRE-TRANSITIONAL AND TRANSITIONAL DISKS

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

Dobinson, Jack; Leinhardt, Zoë M.; Dodson-Robinson, Sarah E.

Transitional and pre-transitional disks can be explained by a number of mechanisms. This work aims to find a single observationally detectable marker that would imply a planetary origin for the gap and, therefore, indirectly indicate the presence of a young planet. N-body simulations were conducted to investigate the effect of an embedded planet of one Jupiter mass on the production of instantaneous collisional dust derived from a background planetesimal disk. Our new model allows us to predict the dust distribution and resulting observable markers with greater accuracy than previous works. Dynamical influences from a planet on a circular orbit aremore » shown to enhance dust production in the disk interior and exterior to the planet orbit, while removing planetesimals from the orbit itself, creating a clearly defined gap. In the case of an eccentric planet, the gap opened by the planet is not as clear as the circular case, but there is a detectable asymmetry in the dust disk.« less

Establishment of a new human pre-B acute lymphoblastic leukemia cell line (KMO-90) with 1;19 translocation carrying p53 gene alterations.

PubMed

Sotomatsu, M; Hayashi, Y; Kawamura, M; Yugami, S; Shitara, T

1993-10-01

A new human pre-B acute lymphoblastic leukemia cell line (KMO-90) was established from the bone marrow sample of a 12-year-old girl with acute lymphoblastic leukemia (ALL) carrying 1;19 chromosome translocation. KMO-90 cells expressed HLA-DR, CD10, CD19, and CD22 antigens. These cells had also cytoplasmic immunoglobulin lacking surface immunoglobulin, indicating that these had a pre-B phenotype. Chromosome analysis of this cell line showed 48, XX, +8, +19, t(1;19)(q23;p13). Southern blot analysis showed the same sized rearrangements of the E2A gene in KMO-90 cells as those in the original leukemic cells. By means of reverse transcriptase-polymerase chain reaction analysis, we detected E2A/PBX1 fusion transcripts in KMO-90 cells. KMO-90 is useful when studying the role of the 1;19 translocation in the etiology of pre-B ALL. Furthermore, we studied alterations of the p53 gene in this cell line by polymerase chain reaction, single-strand conformation polymorphism analysis. KMO-90 cells were identified to have a point mutation at codon 177 (CCC-->TCC) of the p53 gene, suggesting that alterations of the p53 gene may have an important role in the establishment of this cell line.

Factors favoring regain of the lost vertical spinal height through posterior spinal fusion in adolescent idiopathic scoliosis.

PubMed

Shi, Benlong; Mao, Saihu; Xu, Leilei; Sun, Xu; Liu, Zhen; Zhu, Zezhang; Lam, Tsz Ping; Cheng, Jack Cy; Ng, Bobby; Qiu, Yong

2016-07-04

Height gain is a common beneficial consequence following correction surgery in adolescent idiopathic scoliosis (AIS), yet little is known concerning factors favoring regain of the lost vertical spinal height (SH) through posterior spinal fusion. A consecutive series of AIS patients from February 2013 to August 2015 were reviewed. Surgical changes in SH (ΔSH), as well as the multiple coronal and sagittal deformity parameters were measured and correlated. Factors associated with ΔSH were identified through Pearson correlation analysis and multivariate regression analysis. A total of 172 single curve and 104 double curve patients were reviewed. The ΔSH averaged 2.5 ± 0.9 cm in single curve group and 2.9 ± 1.0 cm in double curve group. The multivariate regression analysis revealed the following pre-operative variables contributed significantly to ΔSH: pre-op Cobb angle, pre-op TK (single curve group only), pre-op GK (double curve group only) and pre-op LL (double curve group only) (p < 0.05). Thus change in height (in cm) = 0.044 × (pre-op Cobb angle) + 0.012 × (pre-op TK) (Single curve, adjusted R(2) = 0.549) or 0.923 + 0.021 × (pre-op Cobb angle1) + 0.028 × (pre-op Cobb angle2) + 0.015 × (pre-op GK)-0.012 × (pre-op LL) (Double curve, adjusted R(2) = 0.563). Severer pre-operative coronal Cobb angle and greater sagittal curves were beneficial factors favoring more contribution to the surgical lengthening effect in vertical spinal height in AIS.

Evolving gene regulation networks into cellular networks guiding adaptive behavior: an outline how single cells could have evolved into a centralized neurosensory system

PubMed Central

Fritzsch, Bernd; Jahan, Israt; Pan, Ning; Elliott, Karen L.

2014-01-01

Understanding the evolution of the neurosensory system of man, able to reflect on its own origin, is one of the major goals of comparative neurobiology. Details of the origin of neurosensory cells, their aggregation into central nervous systems and associated sensory organs, their localized patterning into remarkably different cell types aggregated into variably sized parts of the central nervous system begin to emerge. Insights at the cellular and molecular level begin to shed some light on the evolution of neurosensory cells, partially covered in this review. Molecular evidence suggests that high mobility group (HMG) proteins of pre-metazoans evolved into the definitive Sox [SRY (sex determining region Y)-box] genes used for neurosensory precursor specification in metazoans. Likewise, pre-metazoan basic helix-loop-helix (bHLH) genes evolved in metazoans into the group A bHLH genes dedicated to neurosensory differentiation in bilaterians. Available evidence suggests that the Sox and bHLH genes evolved a cross-regulatory network able to synchronize expansion of precursor populations and their subsequent differentiation into novel parts of the brain or sensory organs. Molecular evidence suggests metazoans evolved patterning gene networks early and not dedicated to neuronal development. Only later in evolution were these patterning gene networks tied into the increasing complexity of diffusible factors, many of which were already present in pre-metazoans, to drive local patterning events. It appears that the evolving molecular basis of neurosensory cell development may have led, in interaction with differentially expressed patterning genes, to local network modifications guiding unique specializations of neurosensory cells into sensory organs and various areas of the central nervous system. PMID:25416504

Earth Systems Science Curriculum Choices for Pre-Service Teachers at San Jose State University

NASA Astrophysics Data System (ADS)

Messina, P.; Metzger, E. P.

2008-12-01

San José State University was a member of the original ESSEA consortium (2003-05), and it continues its participation with the broadening ESSEA community. Having hosted the original Middle- and High School Teachers' ESSEA courses, the Geology Department and Program in Science Education have maintained their commitments toward supporting pre- and in-service teachers in geoscience concept competency and effective pedagogy. We have witnessed an encouraging trend in the numbers of K-8 (multiple subject) pre-service teachers who have enrolled in our in-house ESSEA-inspired course: Geology 103 (Earth Systems and the Environment). We have also seen an influx of prospective secondary (single subject) teachers seeking credentials in non- geoscience disciplines. California teacher credentialing requirements, especially when layered on the increasing demands of major fields of study and the California State University System's hefty General Education mandates, give prospective teachers little latitude in their academic programs. Geology 103 was developed to satisfy three logistical objectives: to comply with "geoscience content competency" as defined by the California Commission on Teacher Credentialing (CCTC); to fulfill one of the CSU's upper-division General Education requirements, and to develop science process skills in a population that may never have had similar prior opportunities. The course is offered in two modalities: online and on-campus. The Web-based sections are currently comparing the relative effectiveness of two dissimilar online learning modalities and assessments: one delivers video/audio/animated "podcasts," while the other requires student involvement through interactive Flash media. The course is taught by professors with joint appointments in the Department of Geology and Program in Science Education, and by current and former classroom teachers to ensure that geoscience content knowledge is achieved through inquiry, systems analyses, and other methods promoting enduring understandings.

Evolving gene regulatory networks into cellular networks guiding adaptive behavior: an outline how single cells could have evolved into a centralized neurosensory system.

PubMed

Fritzsch, Bernd; Jahan, Israt; Pan, Ning; Elliott, Karen L

2015-01-01

Understanding the evolution of the neurosensory system of man, able to reflect on its own origin, is one of the major goals of comparative neurobiology. Details of the origin of neurosensory cells, their aggregation into central nervous systems and associated sensory organs and their localized patterning leading to remarkably different cell types aggregated into variably sized parts of the central nervous system have begun to emerge. Insights at the cellular and molecular level have begun to shed some light on the evolution of neurosensory cells, partially covered in this review. Molecular evidence suggests that high mobility group (HMG) proteins of pre-metazoans evolved into the definitive Sox [SRY (sex determining region Y)-box] genes used for neurosensory precursor specification in metazoans. Likewise, pre-metazoan basic helix-loop-helix (bHLH) genes evolved in metazoans into the group A bHLH genes dedicated to neurosensory differentiation in bilaterians. Available evidence suggests that the Sox and bHLH genes evolved a cross-regulatory network able to synchronize expansion of precursor populations and their subsequent differentiation into novel parts of the brain or sensory organs. Molecular evidence suggests metazoans evolved patterning gene networks early, which were not dedicated to neuronal development. Only later in evolution were these patterning gene networks tied into the increasing complexity of diffusible factors, many of which were already present in pre-metazoans, to drive local patterning events. It appears that the evolving molecular basis of neurosensory cell development may have led, in interaction with differentially expressed patterning genes, to local network modifications guiding unique specializations of neurosensory cells into sensory organs and various areas of the central nervous system.

Origin of life: hypothesized roles of high-energy electrical discharges, infrared radiation, thermosynthesis and pre-photosynthesis.

PubMed

Trevors, J T

2012-12-01

The hypothesis is proposed that during the organization of pre-biotic bacterial cell(s), high-energy electrical discharges, infrared radiation (IR), thermosynthesis and possibly pre-photosynthesis were central to the origin of life. High-energy electrical discharges generated some simple organic molecules available for the origin of life. Infrared radiation, both incoming to the Earth and generated on the cooling Earth with day/night and warming/cooling cycles, was a component of heat engine thermosynthesis before enzymes and the genetic code were present. Eventually, a primitive forerunner of photosynthesis and the capability to capture visible light emerged. In addition, the dual particle-wave nature of light is discussed from the perspective that life requires light acting both as a wave and particle.

Phylogenomics of palearctic Formica species suggests a single origin of temporary parasitism and gives insights to the evolutionary pathway toward slave-making behaviour.

PubMed

Romiguier, Jonathan; Rolland, Jonathan; Morandin, Claire; Keller, Laurent

2018-03-28

The ants of the Formica genus are classical model species in evolutionary biology. In particular, Darwin used Formica as model species to better understand the evolution of slave-making, a parasitic behaviour where workers of another species are stolen to exploit their workforce. In his book "On the Origin of Species" (1859), Darwin first hypothesized that slave-making behaviour in Formica evolved in incremental steps from a free-living ancestor. The absence of a well-resolved phylogenetic tree of the genus prevent an assessment of whether relationships among Formica subgenera are compatible with this scenario. In this study, we resolve the relationships among the 4 palearctic Formica subgenera (Formica str. s., Coptoformica, Raptiformica and Serviformica) using a phylogenomic dataset of 945 genes for 16 species. We provide a reference tree resolving the relationships among the main Formica subgenera with high bootstrap supports. The branching order of our tree suggests that the free-living lifestyle is ancestral in the Formica genus and that parasitic colony founding could have evolved a single time, probably acting as a pre-adaptation to slave-making behaviour. This phylogenetic tree provides a solid backbone for future evolutionary studies in the Formica genus and slave-making behaviour.

A Single-Batch Fermentation System to Simulate Human Colonic Microbiota for High-Throughput Evaluation of Prebiotics

PubMed Central

Sasaki, Daisuke; Fukuda, Itsuko; Tanaka, Kosei; Yoshida, Ken-ichi; Kondo, Akihiko; Osawa, Ro

2016-01-01

We devised a single-batch fermentation system to simulate human colonic microbiota from fecal samples, enabling the complex mixture of microorganisms to achieve densities of up to 1011 cells/mL in 24 h. 16S rRNA gene sequence analysis of bacteria grown in the system revealed that representatives of the major phyla, including Bacteroidetes, Firmicutes, and Actinobacteria, as well as overall species diversity, were consistent with those of the original feces. On the earlier stages of fermentation (up to 9 h), trace mixtures of acetate, lactate, and succinate were detectable; on the later stages (after 24 h), larger amounts of acetate accumulated along with some of propionate and butyrate. These patterns were similar to those observed in the original feces. Thus, this system could serve as a simple model to simulate the diversity as well as the metabolism of human colonic microbiota. Supplementation of the system with several prebiotic oligosaccharides (including fructo-, galacto-, isomalto-, and xylo-oligosaccharides; lactulose; and lactosucrose) resulted in an increased population in genus Bifidobacterium, concomitant with significant increases in acetate production. The results suggested that this fermentation system may be useful for in vitro, pre-clinical evaluation of the effects of prebiotics prior to testing in humans. PMID:27483470

[The brothers of Jumiege--the peripheral nervous system in early French mythology].

PubMed

Brean, Are

2002-03-20

This article reviews the process of discovery of the nervous system from Pythagoras (570-500 BC) to Galen (130-201 AD). After Galen, no anatomical studies were performed before the renaissance. According to a legend, probably produced for political reasons, two brothers, sons of the French king Clovis II, revolted against their father and were sentenced to loose their physical powers by having the nerves of their arms and legs cut. They were then set adrift on the river Seine, stranding at the Jumiège monastery. The earliest written version of this legend stems from the fourteenth century; it was probably a part of the local French mythology. This indicates that the existence of the peripheral nervous system, and therefore also in part the knowledge contained in the early anatomical works, quite early may have been more or less known outside academic circles.

Extinction of Harrington's mountain goat

PubMed Central

Mead, Jim I.; Martin, Paul S.; Euler, Robert C.; Long, Austin; Jull, A. J. T.; Toolin, Laurence J.; Donahue, Douglas J.; Linick, T. W.

1986-01-01

Keratinous horn sheaths of the extinct Harrington's mountain goat, Oreamnos harringtoni, were recovered at or near the surface of dry caves of the Grand Canyon, Arizona. Twenty-three separate specimens from two caves were dated nondestructively by the tandem accelerator mass spectrometer (TAMS). Both the TAMS and the conventional dates indicate that Harrington's mountain goat occupied the Grand Canyon for at least 19,000 years prior to becoming extinct by 11,160 ± 125 radiocarbon years before present. The youngest average radiocarbon dates on Shasta ground sloths, Nothrotheriops shastensis, from the region are not significantly younger than those on extinct mountain goats. Rather than sequential extinction with Harrington's mountain goat disappearing from the Grand Canyon before the ground sloths, as one might predict in view of evidence of climatic warming at the time, the losses were concurrent. Both extinctions coincide with the regional arrival of Clovis hunters. Images PMID:16593655

Academic Achievement of Legal Immigrants’ Children: The Roles of Parents’ Pre- and Post-migration Characteristics in Origin-Group Differences

PubMed Central

Pong, Suet-ling; Landale, Nancy S.

2012-01-01

Using data from the New Immigrant Survey, a study based on a nationally representative sample of legal immigrants, the present study extends prior research on the academic outcomes of immigrants’ children by examining the roles of pre- and post-migration parent characteristics and the home environment. An analysis of 2,147 children ages 6-12 shows that parents’ pre-migration education is more strongly associated with children’s academic achievement than any other pre- or post-migration attribute. Pre-migration parental attributes account for the test score disadvantage of Mexican-origin children of legal immigrants, relative to their non-Latino counterparts. The findings reveal continuities and discontinuities in parental SES and demonstrate that what parents bring to the United States and their experiences after arrival influence children’s academic achievement. PMID:22966922

The Origin of Life from the Astrophysical Point of View

NASA Astrophysics Data System (ADS)

Yeghikyan, Ararat

2017-11-01

Тhe problem of the origin of life is discussed from the astrophysical point of view. Most biologists and geologists up to the present time believe that Life was originated on the Earth in some initial natural chemical pre-reactors, where a mixture of water, ammonia, methane containing species and some other substances, under the influence of an energy source like, e.g. lightning, turned into quite complex compounds such as amino acids and complex hydrocarbons. In fact, under conditions of the primordial Earth, it is not possible to obtain such pre-biological molecules by a-bio-chemical methods, as discussed in this lecture. Instead, an astrophysical view of the problem of the origin of life on the Earth is proposed and it is recalled that the biological evolution on the Earth was preceded by the chemical evolution of complex chemical compounds, mostly under extraterrestrial conditions, where it is only possible to form optically active amino acids, sugars and hydrocarbon is necessary for constructing the first pre-biomolecules .

Origin Licensing Requires ATP Binding and Hydrolysis by the MCM Replicative Helicase

PubMed Central

Coster, Gideon; Frigola, Jordi; Beuron, Fabienne; Morris, Edward P.; Diffley, John F.X.

2014-01-01

Summary Loading of the six related Minichromosome Maintenance (MCM) proteins as head-to-head double hexamers during DNA replication origin licensing is crucial for ensuring once-per-cell-cycle DNA replication in eukaryotic cells. Assembly of these prereplicative complexes (pre-RCs) requires the Origin Recognition Complex (ORC), Cdc6, and Cdt1. ORC, Cdc6, and MCM are members of the AAA+ family of ATPases, and pre-RC assembly requires ATP hydrolysis. Here we show that ORC and Cdc6 mutants defective in ATP hydrolysis are competent for origin licensing. However, ATP hydrolysis by Cdc6 is required to release nonproductive licensing intermediates. We show that ATP binding stabilizes the wild-type MCM hexamer. Moreover, by analyzing MCM containing mutant subunits, we show that ATP binding and hydrolysis by MCM are required for Cdt1 release and double hexamer formation. This work alters our view of how ATP is used by licensing factors to assemble pre-RCs. PMID:25087873

Emerging functions of alternative splicing coupled with nonsense-mediated decay.

PubMed

Hamid, Fursham M; Makeyev, Eugene V

2014-08-01

Higher eukaryotes rely on AS (alternative splicing) of pre-mRNAs (mRNA precursors) to generate more than one protein product from a single gene and to regulate mRNA stability and translational activity. An important example of the latter function involves an interplay between AS and NMD (nonsense-mediated decay), a cytoplasmic quality control mechanism eliminating mRNAs containing PTCs (premature translation termination codons). Although originally identified as an error surveillance process, AS-NMD additionally provides an efficient strategy for deterministic regulation of gene expression outputs. In this review, we discuss recently published examples of AS-NMD and delineate functional contexts where recurrent use of this mechanism orchestrates expression of important genes.

The plant cell cycle: Pre-Replication complex formation and controls

PubMed Central

Brasil, Juliana Nogueira; Costa, Carinne N. Monteiro; Cabral, Luiz Mors; Ferreira, Paulo C. G.; Hemerly, Adriana S.

2017-01-01

Abstract The multiplication of cells in all living organisms requires a tight regulation of DNA replication. Several mechanisms take place to ensure that the DNA is replicated faithfully and just once per cell cycle in order to originate through mitoses two new daughter cells that contain exactly the same information from the previous one. A key control mechanism that occurs before cells enter S phase is the formation of a pre-replication complex (pre-RC) that is assembled at replication origins by the sequential association of the origin recognition complex, followed by Cdt1, Cdc6 and finally MCMs, licensing DNA to start replication. The identification of pre-RC members in all animal and plant species shows that this complex is conserved in eukaryotes and, more importantly, the differences between kingdoms might reflect their divergence in strategies on cell cycle regulation, as it must be integrated and adapted to the niche, ecosystem, and the organism peculiarities. Here, we provide an overview of the knowledge generated so far on the formation and the developmental controls of the pre-RC mechanism in plants, analyzing some particular aspects in comparison to other eukaryotes. PMID:28304073

The Chelyabinsk superbolide: a fragment of asteroid 2011 EO40?

NASA Astrophysics Data System (ADS)

de la Fuente Marcos, C.; de la Fuente Marcos, R.

2013-11-01

Bright fireballs or bolides are caused by meteoroids entering the Earth's atmosphere at high speed. Some have a cometary origin, a few may have originated within the Venus-Earth-Mars region as a result of massive impacts in the remote past but a relevant fraction is likely the result of the break-up of asteroids. Disrupted asteroids produce clusters of fragments or asteroid families and meteoroid streams. Linking a bolide to a certain asteroid family may help to understand its origin and pre-impact dynamical evolution. On 2013 February 15, a superbolide was observed in the skies near Chelyabinsk, Russia. Such a meteor could be the result of the decay of an asteroid and here we explore this possibility applying a multistep approach. First, we use available data and Monte Carlo optimization (validated using 2008 TC3 as template) to obtain a robust solution for the pre-impact orbit of the Chelyabinsk impactor (a = 1.62 au, e = 0.53, i = 3.82°, Ω = 326.41° and ω = 109.44°). Then, we use this most probable orbit and numerical analysis to single out candidates for membership in, what we call, the Chelyabinsk asteroid family. Finally, we perform N-body simulations to either confirm or reject any dynamical connection between candidates and impactor. We find reliable statistical evidence on the existence of the Chelyabinsk cluster. It appears to include multiple small asteroids and two relatively large members: 2007 BD7 and 2011 EO40. The most probable parent body for the Chelyabinsk superbolide is 2011 EO40. The orbits of these objects are quite perturbed as they experience close encounters not only with the Earth-Moon system but also with Venus, Mars and Ceres. Under such conditions, the cluster cannot be older than about 20-40 kyr.

The very young resolved stellar populations around stripped-envelope supernovae

NASA Astrophysics Data System (ADS)

Maund, Justyn R.

2018-05-01

The massive star origins for Type IIP supernovae (SNe) have been established through direct detection of their red supergiants progenitors in pre-explosion observations; however, there has been limited success in the detection of the progenitors of H-deficient SNe. The final fate of more massive stars, capable of undergoing a Wolf-Rayet phase, and the origins of Type Ibc SNe remain debated, including the relative importance of single massive star progenitors or lower mass stars stripped in binaries. We present an analysis of the ages and spatial distributions of massive stars around the sites of 23 stripped-envelope SNe, as observed with the Hubble Space Telescope, to probe the possible origins of the progenitors of these events. Using a Bayesian stellar populations analysis scheme, we find characteristic ages for the populations observed within 150 pc of the target Type IIb, Ib, and Ic SNe to be log (t) = 7.20, 7.05, and 6.57, respectively. The Type Ic SNe in the sample are nearly all observed within 100 pc of young, dense stellar populations. The environment around SN 2002ap is an important exception both in terms of age and spatial properties. These findings may support the hypothesis that stars with Minit > 30 M⊙ produce a relatively large proportion of Type Ibc SNe, and that these SN subtypes arise from progressively more massive progenitors. Significantly higher extinctions are derived towards the populations hosting these SNe than previously used in analysis of constraints from pre-explosion observations. The large initial masses inferred for the progenitors are in stark contrast with the low ejecta masses estimated from SN light curves.

Agreement between pre-operative and intra-operative bacteriological samples in 85 chronic peri-prosthetic infections.

PubMed

Matter-Parrat, V; Ronde-Oustau, C; Boéri, C; Gaudias, J; Jenny, J-Y

2017-04-01

Whether pre-operative microbiological sampling contributes to the management of chronic peri-prosthetic infection remains controversial. We assessed agreement between the results of pre-operative and intra-operative samples in patients undergoing single-stage prosthesis exchange to treat chronic peri-prosthetic infection. Agreement between pre-operative and intra-operative samples exceeds 75% in patients undergoing single-stage exchange of a hip or knee prosthesis to treat chronic peri-prosthetic infection. This single-centre retrospective study included 85 single-stage prosthesis exchange procedures in 82 patients with chronic peri-prosthetic infection at the hip or knee. Agreement between pre-operative and intra-operative sample results was evaluated. Changes to the initial antibiotic regimen made based on the intra-operative sample results were recorded. Of 149 pre-operative samples, 109 yielded positive cultures, in 75/85 cases. Of 452 intra-operative samples, 354 yielded positive cultures, in 85/85 cases. Agreement was complete in 54 (63%) cases and partial in 9 (11%) cases; there was no agreement in the remaining 22 (26%) cases. The complete agreement rate was significantly lower than 75% (P=0.01). The initial antibiotic regimen was inadequate in a single case. Pre-operative sampling may contribute to the diagnosis of peri-prosthetic infection but is neither necessary nor sufficient to confirm the diagnosis and identify the causative agent. The spectrum of the initial antibiotic regimen cannot be safely narrowed based on the pre-operative sample results. We suggest the routine prescription of a probabilistic broad-spectrum antibiotic regimen immediately after the prosthesis exchange, even when a pathogen was identified before surgery. IV, retrospective study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Postnatal Environmental Tobacco Smoke Exposure Related to Behavioral Problems in Children.

PubMed

Chastang, Julie; Baïz, Nour; Cadwallader, Jean Sébastien; Cadwalladder, Jean Sébastien; Robert, Sarah; Dywer, John L; Dywer, John; Charpin, Denis André; Caillaud, Denis; de Blay, Frédéric; Raherison, Chantal; Lavaud, François; Annesi-Maesano, Isabella

2015-01-01

The purpose of this study was to examine the association between pre and post environmental tobacco smoke (ETS) exposure and behavioral problems in schoolchildren. In the cross-sectional 6 cities Study conducted in France, 5221 primary school children were investigated. Pre- and postnatal exposure to secondhand tobacco smoke at home was assessed using a parent questionnaire. Child's behavioral outcomes (emotional symptoms and conduct problems) were evaluated by the Strengths and Difficulties Questionnaire (SDQ) completed by the parents. ETS exposure during the postnatal period and during both pre- and postnatal periods was associated with behavioral problems in children. Abnormal emotional symptoms (internalizing problems) were related to ETS exposure in children who were exposed during the pre- and postnatal periods with an OR of 1.72 (95% Confidence Interval (CI)= 1.36-2.17), whereas the OR was estimated to be 1.38 (95% CI= 1.12-1.69) in the case of postnatal exposure only. Abnormal conduct problems (externalizing problems) were related to ETS exposure in children who were exposed during the pre- and postnatal periods with an OR of 1.94 (95% CI= 1.51-2.50), whereas the OR was estimated to be 1.47 (95% CI=1.17-1.84) in the case of postnatal exposure only. Effect estimates were adjusted for gender, study center, ethnic origin, child age, low parental education, current physician diagnosed asthma, siblings, preterm birth and single parenthood. Postnatal ETS exposure, alone or in association with prenatal exposure, increases the risk of behavioral problems in school-age children.

Rapid amino acid quantitation with pre-column derivatization; ultra-performance reverse phase liquid chromatography and single quadrupole mass spectrometry.

PubMed

Pretorius, Carel J; McWhinney, Brett C; Sipinkoski, Bilyana; Wilce, Alice; Cox, David; McWhinney, Avis; Ungerer, Jacobus P J

2018-03-01

We optimized a quantitative amino acid method with pre-column derivatization, norvaline (nva) internal standard and reverse phase ultra-performance liquid chromatography by replacing the ultraviolet detector with a single quadrupole mass spectrometer (MS nva ). We used 13 C 15 N isotopically labeled amino acid internal standards and a C18 column with 1.6μm particles to optimize the chromatography and to confirm separation of isobaric compounds (MS lis ). We compared the analytical performance of MS nva with MS lis and the original method (UV nva ) with clinical samples. The chromatography time per sample of MS nva was 8min, detection capabilities were <1μmol/L for most components, intermediate imprecisions at low concentrations were <10% and there was negligible carryover. MS nva was linear up to a total amino acid concentration in a sample of approximately 9500μmol/L. The agreements between most individual amino acids were satisfactory compared to UV nva with the latter prone to outliers and suboptimal quantitation of urinary arginine, aspartate, glutamate and methionine. MS nva reliably detected argnininosuccinate, β-alanine, citrulline and cysteine-s-sulfate. MS nva resulted in a more than fivefold increase in operational efficiency with accurate detection of amino acids and metabolic intermediates in clinical samples. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Characterization of dislocation structures and deformation mechanisms in as-grown and deformed directionally solidified NiAl–Mo composites

DOE PAGES

Kwon, J.; Bowers, M. L.; Brandes, M. C.; ...

2015-02-26

In this paper, directionally solidified (DS) NiAl–Mo eutectic composites were strained to plastic strain values ranging from 0% to 12% to investigate the origin of the previously observed stochastic versus deterministic mechanical behaviors of Mo-alloy micropillars in terms of the development of dislocation structures at different pre-strain levels. The DS composites consist of long, [1 0 0] single-crystal Mo-alloy fibers with approximately square cross-sections embedded in a [1 0 0] single-crystal NiAl matrix. Scanning transmission electron microscopy (STEM) and computational stress state analysis were conducted for the current study. STEM of the as-grown samples (without pre-straining) reveal no dislocations inmore » the investigated Mo-alloy fibers. In the NiAl matrix, on the other hand, a(1 0 0)-type dislocations exist in two orthogonal orientations: along the [1 0 0] Mo fiber axis, and wrapped around the fiber axis. They presumably form to accommodate the different thermal contractions of the two phases during cool down after eutectic solidification. At intermediate pre-strain levels (4–8%), a/2(1 1 1)-type dislocations are present in the Mo-alloy fibers and the pre-existing dislocations in the NiAl matrix seem to be swept toward the interphase boundary. Some of the dislocations in the Mo-alloy fibers appear to be transformed from a(1 0 0)-type dislocations present in the NiAl matrix. Subsequently, the transformed dislocations in the fibers propagate through the NiAl matrix as a(1 1 1) dislocations and aid in initiating additional slip bands in adjacent fibers. Thereafter, co-deformation presumably occurs by (1 1 1) slip in both phases. With a further increase in the pre-strain level (>10%), multiple a/2(1 1 1)-type dislocations are observed in many locations in the Mo-alloy fibers. Interactions between these systems upon subsequent deformation could lead to stable junctions and persistent dislocation sources. Finally, the transition from stochastic to deterministic, bulk-like behavior in sub-micron Mo-alloy pillars may therefore be related to an increasing number of multiple a(1 1 1) dislocation systems within the Mo fibers with increasing pre-strain, considering that the bulk-like behavior is governed by the forest hardening of these junctions.« less

Pre-terrestrial origin of rust in the Nakhla meteorite

NASA Technical Reports Server (NTRS)

Wentworth, Susan J.; Gooding, James L.

1990-01-01

The authors present quantative elemental compositions and summarize textural evidence for the pre-terrestrial origin of rust on the Nakhla meteorite. The material in question is called 'rust' because its phase composition remains unknown. Compelling evidence for the pre-terrestrial origin of the rust is found in rust veins truncated by fusion crust and preserved as faults in sutured igneous crystals. Rust veins that approach the meteorite's fusion crust become discontinuous and exhibit vugs that suggest partial decrepitation; no veins that penetrate the fusion crust have been found. Because the rust probably contains volatile compounds, it is reasonable to expect that heating near the ablation surface (formed during atmospheric entry to Earth) would encourage devolatilization of the rust. Hence, the absence of rust veins in fusion crust and vugs in rust veins near fusion crust clearly imply that the rust existed in the meteorite before atmospheric entry.

Effectiveness of Child Protection Training for Pre-Service Early Childhood Educators

ERIC Educational Resources Information Center

McKee, Bronagh E.; Dillenburger, Karola

2012-01-01

International evidence confirms that early childhood educators can enter professional practice unprepared for child protection due to inadequate pre-service preparation. This paper makes an original contribution by using the Child Protection Questionnaire for Educators (CPQE) to examine the pre- and post-intervention child maltreatment and…

Alaska Imagery (GOES-WEST) - Satellite Services Division / Office of

Science.gov Websites

-- Dissemination Schedules METEOSAT MTSAT-1R POES -- Satellite Operations -- Satellite Status Pre-Processing Status Pre-Processing -- Dissemination Schedules Original SSD Links SSD Fire Products Precipitation

Hawaii Imagery (GOES-WEST) - Satellite Services Division / Office of

Science.gov Websites

-- Dissemination Schedules METEOSAT MTSAT-1R POES -- Satellite Operations -- Satellite Status Pre-Processing Status Pre-Processing -- Dissemination Schedules Original SSD Links SSD Fire Products Precipitation

Does a single session of reading literary fiction prime enhanced mentalising performance? Four replication experiments of Kidd and Castano (2013).

PubMed

Samur, Dalya; Tops, Mattie; Koole, Sander L

2018-02-01

Prior experiments indicated that reading literary fiction improves mentalising performance relative to reading popular fiction, non-fiction, or not reading. However, the experiments had relatively small sample sizes and hence low statistical power. To address this limitation, the present authors conducted four high-powered replication experiments (combined N = 1006) testing the causal impact of reading literary fiction on mentalising. Relative to the original research, the present experiments used the same literary texts in the reading manipulation; the same mentalising task; and the same kind of participant samples. Moreover, one experiment was pre-registered as a direct replication. In none of the experiments did reading literary fiction have any effect on mentalising relative to control conditions. The results replicate earlier findings that familiarity with fiction is positively correlated with mentalising. Taken together, the present findings call into question whether a single session of reading fiction leads to immediate improvements in mentalising.

Single n-GaN microwire/p-Silicon thin film heterojunction light-emitting diode.

PubMed

Ahn, Jaehui; Mastro, Michael A; Klein, Paul B; Hite, Jennifer K; Feigelson, Boris; Eddy, Charles R; Kim, Jihyun

2011-10-24

The emission and waveguiding properties of individual GaN microwires as well as devices based on an n-GaN microwire/p-Si (100) junction were studied for relevance in optoelectronics and optical circuits. Pulsed photoluminescence of the GaN microwire excited in the transverse or longitudinal direction demonstrated gain. These n-type GaN microwires were positioned mechanically or by dielectrophoretic force onto pre-patterned electrodes on a p-type Si (100) substrate. Electroluminescence from this p-n point junction was characteristic of a heterostructure light-emitting diode. Additionally, waveguiding was observed along the length of the microwire for light originating from photoluminescence as well as from electroluminescence generated at the p-n junction. © 2011 Optical Society of America

Evidence of tungiasis in pre-Hispanic America.

PubMed

Maco, Vicente; Tantaleán, Manuel; Gotuzzo, Eduardo

2011-05-01

Ancient parasites of the genus Tunga originated in America and, during the first half of the 19th century, were transported to the Eastern Hemisphere on transatlantic voyages. Although they were first documented by Spanish chroniclers after the arrival of Columbus, little is known about their presence in pre-Hispanic America. To evaluate the antiquity of tungiasis in America, we assessed several kinds of early documentation, including written evidence and pre-Incan earthenware reproductions. We identified 17 written documents and 4 anthropomorphic figures, of which 3 originated from the Chimu culture and 1 from the Maranga culture. Tungiasis has been endemic to Peru for at least 14 centuries. We also identified a pottery fragment during this study. This fragment is the fourth representation of tungiasis in pre-Hispanic America identified and provides explicit evidence of disease endemicity in ancient Peru.

Evidence of Tungiasis in Pre-Hispanic America

PubMed Central

Tantaleán, Manuel; Gotuzzo, Eduardo

2011-01-01

Ancient parasites of the genus Tunga originated in America and, during the first half of the 19th century, were transported to the Eastern Hemisphere on transatlantic voyages. Although they were first documented by Spanish chroniclers after the arrival of Columbus, little is known about their presence in pre-Hispanic America. To evaluate the antiquity of tungiasis in America, we assessed several kinds of early documentation, including written evidence and pre-Incan earthenware reproductions. We identified 17 written documents and 4 anthropomorphic figures, of which 3 originated from the Chimu culture and 1 from the Maranga culture. Tungiasis has been endemic to Peru for at least 14 centuries. We also identified a pottery fragment during this study. This fragment is the fourth representation of tungiasis in pre-Hispanic America identified and provides explicit evidence of disease endemicity in ancient Peru. PMID:21529395

PrE (Person-Relative-to-Event) Theory of Coping with Threat.

ERIC Educational Resources Information Center

Mulilis, John-Paul; Duval, T. Shelley

The generalizability of Person-Relative-to-Event (PrE) theory, originally applied to disaster-related situations, is investigated in a non-disaster simulation. The PrE theory of coping with threat emphasizes the relationship between level of appraised threat relative to person resources and personal responsibility. This theory has previously been…

26 CFR 1.679-5 - Pre-immigration trusts.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Pre-immigration trusts. 1.679-5 Section 1.679-5...) INCOME TAXES Grantors and Others Treated As Substantial Owners § 1.679-5 Pre-immigration trusts. (a) In... transferring property to a foreign trust (the original transfer), the individual is treated as having...

Unemployment in Iraqi Refugees: The Interaction of Pre and Post-Displacement Trauma

PubMed Central

Wright, A. Michelle; Dhalimi, Abir; Lumley, Mark A.; Jamil, Hikmet; Pole, Nnamdi; Arnetz, Judith E.; Arnetz, Bengt B.

2016-01-01

Previous refugee research has been unable to link pre-displacement trauma with unemployment in the host country. The current study assessed the role of pre-displacement trauma, post-displacement trauma, and the interaction of both trauma types to prospectively examine unemployment in a random sample of newly-arrived Iraqi refugees. Participants (N=286) were interviewed three times over the first two years post-arrival. Refugees were assessed for pre-displacement trauma exposure, post-displacement trauma exposure, a history of unemployment in the country of origin and host country, and symptoms of posttraumatic stress disorder (PTSD) and depression. Analyses found that neither pre-displacement nor post-displacement trauma independently predicted unemployment 2 years post-arrival; however, the interaction of pre and post-displacement trauma predicted 2-year unemployment. Refugees with high levels of both pre and post-displacement trauma had a 91% predicted probability of unemployment, whereas those with low levels of both traumas had a 20% predicted probability. This interaction remained significant after controlling for sociodemographic variables and mental health upon arrival to the U.S. Resettlement agencies and community organizations should consider the interactive effect of encountering additional trauma after escaping the hardships of the refugee's country of origin. PMID:27535348

Continuing dental education in radiation protection: knowledge retention following a postgraduate course.

PubMed

Absi, E G; Drage, N A; Thomas, H S; Newcombe, R G; Cowpe, J

2011-08-01

To evaluate medium-term knowledge retention of dental personnel following attendance at a postgraduate course in radiation protection. Knowledge was measured using identical pre- and post-course validated single best-answer multiple-choice instruments, administered immediately before and after training and at follow-up at 6 or 12 months. These comprise 16 questions each with 5 choices. The range of possible scores was from 0 to 16, and scores were scaled to percentages. Participants were predominantly dental practitioners, but a minority consisted of dental care professionals (dental nurses, hygienists and therapists). Of 285 participants, 272 (95.4%) completed both pre- and post-course questionnaires. One hundred and seventeen (43%) of these also completed the follow-up test, but only 109 (40%) individuals could be linked to the original course. Mean (standard deviation) pre-, post-course and follow-up-corrected percentage scores were 39.1 (16.1), 74.6 (16.9) and 58.9 (22.7), respectively. There was attrition in knowledge at follow-up: the average increase in adjusted score after training was 35.5 points, but only 56% of this was retained at follow-up. Paired t-tests confirmed that the mean score at follow-up was firmly intermediate between the pre- and post-course scores. Of the 109 participants, 7 (6%) achieved a satisfactory score pre-training, 82 (75%) immediately post-training and 41 (38%) at follow-up. There were gross differences between the levels of performance achieved for the eight subject areas tested. Immediate post-course assessments have indicated that current postgraduate courses in radiation protection are effective. However, a substantial amount of knowledge is lost by 6-12 months following course attendance. To achieve long-term knowledge retention, early or repeated reinforcement may be necessary. © 2011 John Wiley & Sons A/S.

Advanced linear and nonlinear compensations for 16QAM SC-400G unrepeatered transmission system

NASA Astrophysics Data System (ADS)

Zhang, Junwen; Yu, Jianjun; Chien, Hung-Chang

2018-02-01

Digital signal processing (DSP) with both linear equalization and nonlinear compensations are studied in this paper for the single-carrier 400G system based on 65-GBaud 16-quadrature amplitude modulation (QAM) signals. The 16-QAM signals are generated and pre-processed with pre-equalization (Pre-EQ) and Look-up-Table (LUT) based pre-distortion (Pre-DT) at the transmitter (Tx)-side. The implementation principle of training-based equalization and pre-distortion are presented here in this paper with experimental studies. At the receiver (Rx)-side, fiber-nonlinearity compensation based on digital backward propagation (DBP) are also utilized to further improve the transmission performances. With joint LUT-based Pre-DT and DBP-based post-compensation to mitigate the opto-electronic components and fiber nonlinearity impairments, we demonstrate the unrepeatered transmission of 1.6Tb/s based on 4-lane 400G single-carrier PDM-16QAM over 205-km SSMF without distributed amplifier.

RecQL4 is required for the association of Mcm10 and Ctf4 with replication origins in human cells

PubMed Central

Im, Jun-Sub; Park, Soon-Young; Cho, Won-Ho; Bae, Sung-Ho; Hurwitz, Jerard; Lee, Joon-Kyu

2015-01-01

Though RecQL4 was shown to be essential for the initiation of DNA replication in mammalian cells, its role in initiation is poorly understood. Here, we show that RecQL4 is required for the origin binding of Mcm10 and Ctf4, and their physical interactions and association with replication origins are controlled by the concerted action of both CDK and DDK activities. Although RecQL4-dependent binding of Mcm10 and Ctf4 to chromatin can occur in the absence of pre-replicative complex, their association with replication origins requires the presence of the pre-replicative complex and CDK and DDK activities. Their association with replication origins and physical interactions are also targets of the DNA damage checkpoint pathways which prevent initiation of DNA replication at replication origins. Taken together, the RecQL4-dependent association of Mcm10 and Ctf4 with replication origins appears to be the first important step controlled by S phase promoting kinases and checkpoint pathways for the initiation of DNA replication in human cells. PMID:25602958

Pre- and post-head processing for single- and double-scrambled sentences of a head-final language as measured by the eye tracking method.

PubMed

Tamaoka, Katsuo; Asano, Michiko; Miyaoka, Yayoi; Yokosawa, Kazuhiko

2014-04-01

Using the eye-tracking method, the present study depicted pre- and post-head processing for simple scrambled sentences of head-final languages. Three versions of simple Japanese active sentences with ditransitive verbs were used: namely, (1) SO₁O₂V canonical, (2) SO₂O₁V single-scrambled, and (3) O₁O₂SV double-scrambled order. First pass reading times indicated that the third noun phrase just before the verb in both single- and double-scrambled sentences required longer reading times compared to canonical sentences. Re-reading times (the sum of all fixations minus the first pass reading) showed that all noun phrases including the crucial phrase before the verb in double-scrambled sentences required longer re-reading times than those required for single-scrambled sentences; single-scrambled sentences had no difference from canonical ones. Therefore, a single filler-gap dependency can be resolved in pre-head anticipatory processing whereas two filler-gap dependencies require much greater cognitive loading than a single case. These two dependencies can be resolved in post-head processing using verb agreement information.

Latino Immigrants' Biological Parents' Histories of Substance Use Problems in Their Country of Origin Predict Their Pre- and Post-Immigration Alcohol Use Problems.

PubMed

Blackson, Timothy C; De La Rosa, Mario; Sanchez, Mariana; Li, Tan

2015-01-01

No studies to date have assessed whether recent young adult (aged 18-34) Latino immigrants' biological parents' histories of substance use problems (BPHSUP) in their country of origin predict their alcohol use problems at pre- and post-immigration to the United States (US). BPHSUP in their country of origin were assessed via interviews conducted by bilingual Latino researchers with recent Latino immigrants primarily from Cuba and Central and South America recruited through respondent-driven sampling at the time of their immigration to southeastern US. Three waves of data were collected to document Latino immigrants' severity of alcohol use problems at pre-immigration and 2 annual post-immigration follow-up assessments. BPHSUP+/- status was used as a predictor of Latinos' (N = 452; 45.8% female, 54.2% male) Alcohol Use Disorders Identification Test (AUDIT) scores at pre- and post-immigration with age, education, and income as covariates as wells as odds ratios for AUDIT classifications of hazardous use, harmful use, and dependence. BPHSUP+ status predicted Latino immigrants' higher AUDIT scores pre- and post-immigration by gender (P < .01) compared with Latino immigrants of BPHSUP- status, controlling for age, education, and income. BPHSUP+ status predicted odds ratios of 3.45 and 2.91 for AUDIT alcohol dependence classification for men and women, respectively. This study documents that BPHSUP+/- status in their country of origin predict their young adult Latino offspring's severity of alcohol use problems pre- and post-immigration. These results may inform (1) community-based health care providers to screen recent young adult Latino immigrants for their BPHSUP+/- status and severity of alcohol use problems to redirect trajectories away from alcohol use disorders toward more normative post-immigration outcomes through culturally relevant prevention services and (2) future research advantages of differential susceptibility theory. Implications for future research and the need for replication studies in other geographic regions of the US are discussed.

Scientific Evidence as Content Knowledge: A Replication Study with English and Turkish Pre-Service Primary Teachers

ERIC Educational Resources Information Center

Roberts, Ros; Sahin-Pekmez, Esin

2012-01-01

Pre-service teachers around the world need to develop their content knowledge of scientific evidence to meet the requirements of recent school curriculum developments which prepare pupils to be scientifically literate. This research reports a replication study in Turkey of an intervention originally carried out with pre-service primary teachers in…

Evolution Born of Moisture: Analogies and Parallels Between Anaximander's Ideas on Origin of Life and Man and Later Pre-Darwinian and Darwinian Evolutionary Concepts.

PubMed

Kočandrle, Radim; Kleisner, Karel

2013-01-01

This study focuses on the origin of life as presented in the thought of Anaximander of Miletus but also points to some parallel motifs found in much later conceptions of both the pre-Darwinian German romantic science and post-Darwinian biology. According to Anaximander, life originated in the moisture associated with earth (mud). This moist environment hosted the first living creatures that later populated the dry land. In these descriptions, one can trace the earliest hints of the notion of environmental adaptation. The origin of humans was seen as connected in some way with fish: ancient humans were supposed to have developed inside fish-like animals. Anaximander took into account changes in the development of living creatures (adaptations) and speculated on the origins of humans. Similar ideas are found also in the writings of much later, eighteenth and nineteenth century authors who were close to the tradition of German romantic science. We do not argue that these later concepts are in any way directly linked with those of the pre-Socratics, but they show surprising parallels in, e.g., the hypothesis that life originated in a moist environment or the supposition that human developed from fish-like ancestors. These transformations are seen as a consequence of timeless logic rather than as evolution in historical terms. Despite the accent on the origin of living things, both Anaximander and the later Naturphilosophen lack in their notions the element most characteristic of Darwin's thought, that is, the emphasis on historicity and uniqueness of all that comes into being.

Methods for producing silicon carbide architectural preforms

NASA Technical Reports Server (NTRS)

DiCarlo, James A. (Inventor); Yun, Hee (Inventor)

2010-01-01

Methods are disclosed for producing architectural preforms and high-temperature composite structures containing high-strength ceramic fibers with reduced preforming stresses within each fiber, with an in-situ grown coating on each fiber surface, with reduced boron within the bulk of each fiber, and with improved tensile creep and rupture resistance properties for each fiber. The methods include the steps of preparing an original sample of a preform formed from a pre-selected high-strength silicon carbide ceramic fiber type, placing the original sample in a processing furnace under a pre-selected preforming stress state and thermally treating the sample in the processing furnace at a pre-selected processing temperature and hold time in a processing gas having a pre-selected composition, pressure, and flow rate. For the high-temperature composite structures, the method includes additional steps of depositing a thin interphase coating on the surface of each fiber and forming a ceramic or carbon-based matrix within the sample.

Partial removal of correlated noise in thermal imagery

NASA Astrophysics Data System (ADS)

Borel, Christoph C.; Cooke, Bradly J.; Laubscher, Bryan E.

1996-05-01

Correlated noise occurs in many imaging systems such as scanners and push-broom imagers. The sources of correlated noise can be from the detectors, pre-amplifiers and sampling circuits. Correlated noise appears as streaking along the scan direction of a scanner or in the along track direction of a push-broom imager. We have developed algorithms to simulate correlated noise and pre-filter to reduce the amount of streaking while not destroying the scene content. The pre-filter in the Fourier domain consists of the product of two filters. One filter models the correlated noise spectrum, the other is a windowing function, e.g. Gaussian or Hanning window with variable width to block high frequency noise away from the origin of the Fourier Transform of the image data. We have optimized the filter parameters for various scenes and find improvements of the RMS error of the original minus the pre-filtered noisy image.

Methods of Science Investigation Part 2: Results of Implementation of a Curriculum Fostering Original Scientific Research

NASA Astrophysics Data System (ADS)

Danch, J. M.

2008-12-01

Originally designed to allow secondary students with special needs to participate in original scientific research, the Methods of Science Curriculum was piloted in 2008. Students participating included those with special needs, English language learners, and the general population. Students were incrementally graduated from traditional inquiry activities towards authentic student-generated research projects. Students were evaluated via class work grades, an in-school symposium and a pre/post test. 100 percent of participants successfully completed and presented their original research. The pre/post evaluation demonstrated improvement for 91 percent of participants. An unanticipated result was the performance and growth of English language learners, possibly because of the emphasis on the creative and active process of science rather than vocabulary. A teacher-training program is being developed for expansion of the curriculum to additional schools in 2009.

Postglacial viability and colonization in North America’s ice-free corridor

NASA Astrophysics Data System (ADS)

Pedersen, Mikkel W.; Ruter, Anthony; Schweger, Charles; Friebe, Harvey; Staff, Richard A.; Kjeldsen, Kristian K.; Mendoza, Marie L. Z.; Beaudoin, Alwynne B.; Zutter, Cynthia; Larsen, Nicolaj K.; Potter, Ben A.; Nielsen, Rasmus; Rainville, Rebecca A.; Orlando, Ludovic; Meltzer, David J.; Kjær, Kurt H.; Willerslev, Eske

2016-09-01

During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr BP), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor. We find evidence of steppe vegetation, bison and mammoth by approximately 12.6 cal. kyr BP, followed by open forest, with evidence of moose and elk at about 11.5 cal. kyr BP, and boreal forest approximately 10 cal. kyr BP. Our findings reveal that the first Americans, whether Clovis or earlier groups in unglaciated North America before 12.6 cal. kyr BP, are unlikely to have travelled by this route into the Americas. However, later groups may have used this north-south passageway.

Postglacial viability and colonization in North America's ice-free corridor.

PubMed

Pedersen, Mikkel W; Ruter, Anthony; Schweger, Charles; Friebe, Harvey; Staff, Richard A; Kjeldsen, Kristian K; Mendoza, Marie L Z; Beaudoin, Alwynne B; Zutter, Cynthia; Larsen, Nicolaj K; Potter, Ben A; Nielsen, Rasmus; Rainville, Rebecca A; Orlando, Ludovic; Meltzer, David J; Kjær, Kurt H; Willerslev, Eske

2016-09-01

During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr bp), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor. We find evidence of steppe vegetation, bison and mammoth by approximately 12.6 cal. kyr bp, followed by open forest, with evidence of moose and elk at about 11.5 cal. kyr bp, and boreal forest approximately 10 cal. kyr bp. Our findings reveal that the first Americans, whether Clovis or earlier groups in unglaciated North America before 12.6 cal. kyr bp, are unlikely to have travelled by this route into the Americas. However, later groups may have used this north-south passageway.

Comparative study of antioxidant properties and total phenolic content of 30 plant extracts of industrial interest using DPPH, ABTS, FRAP, SOD, and ORAC assays.

PubMed

Dudonné, Stéphanie; Vitrac, Xavier; Coutière, Philippe; Woillez, Marion; Mérillon, Jean-Michel

2009-03-11

Aqueous extracts of 30 plants were investigated for their antioxidant properties using DPPH and ABTS radical scavenging capacity assay, oxygen radical absorbance capacity (ORAC) assay, superoxide dismutase (SOD) assay, and ferric reducing antioxidant potential (FRAP) assay. Total phenolic content was also determined by the Folin-Ciocalteu method. Antioxidant properties and total phenolic content differed significantly among selected plants. It was found that oak (Quercus robur), pine (Pinus maritima), and cinnamon (Cinnamomum zeylanicum) aqueous extracts possessed the highest antioxidant capacities in most of the methods used, and thus could be potential rich sources of natural antioxidants. These extracts presented the highest phenolic content (300-400 mg GAE/g). Mate (Ilex paraguariensis) and clove (Eugenia caryophyllus clovis) aqueous extracts also showed strong antioxidant properties and a high phenolic content (about 200 mg GAE/g). A significant relationship between antioxidant capacity and total phenolic content was found, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants.

The Arrival of Homo sapiens into the Southern Cone at 14,000 Years Ago.

PubMed

Politis, Gustavo G; Gutiérrez, María A; Rafuse, Daniel J; Blasi, Adriana

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America.

Mössbauer spectroscopy on Mars: goethite in the Columbia Hills at Gusev crater

NASA Astrophysics Data System (ADS)

Klingelhöfer, G.; Degrave, E.; Morris, R. V.; van Alboom, A.; de Resende, V. G.; de Souza, P. A.; Rodionov, D.; Schröder, C.; Ming, D. W.; Yen, A.

2005-11-01

In January 2004 the USA space agency NASA landed two rovers on the surface of Mars, both carrying the Mainz Mössbauer spectrometer MIMOS II. The instrument on the Mars-Exploration-Rover (MER) Spirit analyzed soils and rocks on the plains and in the Columbia Hills of Gusev crater landing site on Mars. The surface material in the plains have an olivine basaltic signature [1, 5] suggesting physical rather than chemical weathering processes present in the plains. The Mössbauer signature for the Columbia Hills surface material is very different ranging from nearly unaltered material to highly altered material. Some of the rocks, in particular a rock named Clovis, contain a significant amount of the Fe oxyhydroxide goethite, α-FeOOH, which is mineralogical evidence for aqueous processes because it is formed only under aqueous conditions. In this paper we describe the analysis of these data using hyperfine field distributions (HFD) and discuss the results in comparison to terrestrial analogues.

Single cell cultures of Drosophila neuroectodermal and mesectodermal central nervous system progenitors reveal different degrees of developmental autonomy.

PubMed

Lüer, Karin; Technau, Gerhard M

2009-08-03

The Drosophila embryonic central nervous system (CNS) develops from two sets of progenitor cells, neuroblasts and ventral midline progenitors, which behave differently in many respects. Neuroblasts derive from the neurogenic region of the ectoderm and form the lateral parts of the CNS. Ventral midline precursors are formed by two rows of mesectodermal cells and build the CNS midline. There is plenty of evidence that individual identities are conferred to precursor cells by positional information in the ectoderm. It is unclear, however, how far the precursors can maintain their identities and developmental properties in the absence of normal external signals. To separate the respective contributions of autonomous properties versus extrinsic signals during their further development, we isolated individual midline precursors and neuroectodermal precursors at the pre-mitotic gastrula stage, traced their development in vitro, and analyzed the characteristics of their lineages in comparison with those described for the embryo. Although individually cultured mesectodermal cells exhibit basic characteristics of CNS midline progenitors, the clones produced by these progenitors differ from their in situ counterparts with regard to cell numbers, expression of molecular markers, and the separation of neuronal and glial fate. In contrast, clones derived from individually cultured precursors taken from specific dorsoventral zones of the neuroectoderm develop striking similarities to the lineages of neuroblasts that normally delaminate from these zones and develop in situ. This in vitro analysis allows for the first time a comparison of the developmental capacities in situ and in vitro of individual neural precursors of defined spatial and temporal origin. The data reveal that cells isolated at the pre-mitotic and pre-delamination stage express characteristics of the progenitor type appropriate to their site of origin in the embryo. However, presumptive neuroblasts, once specified in the neuroectoderm, exhibit a higher degree of autonomy regarding generation of their lineages compared to mesectodermal midline progenitors.

Origin and Function of Circulating Plasmablasts during Acute Viral Infections.

PubMed

Fink, Katja

2012-01-01

Activated B cells proliferate and differentiate into antibody-producing cells, long-lived plasma cells, and memory B cells after immunization or infection. Repeated encounter of the same antigen triggers the rapid re-activation of pre-existing specific memory B cells, which then potentially enter new germinal center reactions and differentiate into short-lived plasmablasts or remain in the system as memory B cells. Short-lived class-switched IgG and IgA plasmablasts appear in the circulation transiently and the frequency of these cells can be remarkably high. The specificities and affinities of single plasmablasts in humans have been reported for several viral infections, so far most extensively for influenza and HIV. In general, the immunoglobulin variable regions of plasmablasts are highly mutated and diverse, suggesting that plasmablasts are derived from memory B cells, yet it is unclear which memory B cell subsets are activated and whether activated memory B cells adapt or mature before differentiation. This review summarizes what is known about the phenotype and the origin of human plasmablasts in the context of viral infections and whether these cells can be predictors of long-lived immunity.

Single-Cell Analysis Reveals Early Manifestation of Cancerous Phenotype in Pre-Malignant Esophageal Cells

PubMed Central

Wang, Jiangxin; Shi, Xu; Johnson, Roger H.; Kelbauskas, Laimonas; Zhang, Weiwen; Meldrum, Deirdre R.

2013-01-01

Cellular heterogeneity plays a pivotal role in a variety of functional processes in vivo including carcinogenesis. However, our knowledge about cell-to-cell diversity and how differences in individual cells manifest in alterations at the population level remains very limited mainly due to the lack of appropriate tools enabling studies at the single-cell level. We present a study on changes in cellular heterogeneity in the context of pre-malignant progression in response to hypoxic stress. Utilizing pre-malignant progression of Barrett’s esophagus (BE) as a disease model system we studied molecular mechanisms underlying the progression from metaplastic to dysplastic (pre-cancerous) stage. We used newly developed methods enabling measurements of cell-to-cell differences in copy numbers of mitochondrial DNA, expression levels of a set of mitochondrial and nuclear genes involved in hypoxia response pathways, and mitochondrial membrane potential. In contrast to bulk cell studies reported earlier, our study shows significant differences between metaplastic and dysplastic BE cells in both average values and single-cell parameter distributions of mtDNA copy numbers, mitochondrial function, and mRNA expression levels of studied genes. Based on single-cell data analysis, we propose that mitochondria may be one of the key factors in pre-malignant progression in BE. PMID:24116039

Pre-analytic evaluation of volumetric absorptive microsampling and integration in a mass spectrometry-based metabolomics workflow.

PubMed

Volani, Chiara; Caprioli, Giulia; Calderisi, Giovanni; Sigurdsson, Baldur B; Rainer, Johannes; Gentilini, Ivo; Hicks, Andrew A; Pramstaller, Peter P; Weiss, Guenter; Smarason, Sigurdur V; Paglia, Giuseppe

2017-10-01

Volumetric absorptive microsampling (VAMS) is a novel approach that allows single-drop (10 μL) blood collection. Integration of VAMS with mass spectrometry (MS)-based untargeted metabolomics is an attractive solution for both human and animal studies. However, to boost the use of VAMS in metabolomics, key pre-analytical questions need to be addressed. Therefore, in this work, we integrated VAMS in a MS-based untargeted metabolomics workflow and investigated pre-analytical strategies such as sample extraction procedures and metabolome stability at different storage conditions. We first evaluated the best extraction procedure for the polar metabolome and found that the highest number and amount of metabolites were recovered upon extraction with acetonitrile/water (70:30). In contrast, basic conditions (pH 9) resulted in divergent metabolite profiles mainly resulting from the extraction of intracellular metabolites originating from red blood cells. In addition, the prolonged storage of blood samples at room temperature caused significant changes in metabolome composition, but once the VAMS devices were stored at - 80 °C, the metabolome remained stable for up to 6 months. The time used for drying the sample did also affect the metabolome. In fact, some metabolites were rapidly degraded or accumulated in the sample during the first 48 h at room temperature, indicating that a longer drying step will significantly change the concentration in the sample. Graphical abstract Volumetric absorptive microsampling (VAMS) is a novel technology that allows single-drop blood collection and, in combination with mass spectrometry (MS)-based untargeted metabolomics, represents an attractive solution for both human and animal studies. In this work, we integrated VAMS in a MS-based untargeted metabolomics workflow and investigated pre-analytical strategies such as sample extraction procedures and metabolome stability at different storage conditions. The latter revealed that prolonged storage of blood samples at room temperature caused significant changes in metabolome composition, but if VAMS devices were stored at - 80 °C, the metabolome remained stable for up to 6 months.

Effect of 17 days of bed rest on peak isometric force and unloaded shortening velocity of human soleus fibers

NASA Technical Reports Server (NTRS)

Widrick, J. J.; Romatowski, J. G.; Bain, J. L.; Trappe, S. W.; Trappe, T. A.; Thompson, J. L.; Costill, D. L.; Riley, D. A.; Fitts, R. H.

1997-01-01

The purpose of this study was to examine the effect of prolonged bed rest (BR) on the peak isometric force (P0) and unloaded shortening velocity (V0) of single Ca(2+)-activated muscle fibers. Soleus muscle biopsies were obtained from eight adult males before and after 17 days of 6 degrees head-down BR. Chemically permeabilized single fiber segments were mounted between a force transducer and position motor, activated with saturating levels of Ca2+, and subjected to slack length steps. V0 was determined by plotting the time for force redevelopment vs. the slack step distance. Gel electrophoresis revealed that 96% of the pre- and 87% of the post-BR fibers studied expressed only the slow type I myosin heavy chain isoform. Fibers with diameter > 100 microns made up only 14% of this post-BR type I population compared with 33% of the pre-BR type I population. Consequently, the post-BR type I fibers (n = 147) were, on average, 5% smaller in diameter than the pre-BR type I fibers (n = 218) and produced 13% less absolute P0. BR had no overall effect on P0 per fiber cross-sectional area (P0/CSA), even though half of the subjects displayed a decline of 9-12% in P0/CSA after BR. Type I fiber V0 increased by an average of 34% with BR. Although the ratio of myosin light chain 3 to myosin light chain 2 also rose with BR, there was no correlation between this ratio and V0 for either the pre- or post-BR fibers. In separate fibers obtained from the original biopsies, quantitative electron microscopy revealed a 20-24% decrease in thin filament density, with no change in thick filament density. These results raise the possibility that alterations in the geometric relationships between thin and thick filaments may be at least partially responsible for the elevated V0 of the post-BR type I fibers.

Experimental Investigations on Subsequent Yield Surface of Pure Copper by Single-Sample and Multi-Sample Methods under Various Pre-Deformation.

PubMed

Liu, Gui-Long; Huang, Shi-Hong; Shi, Che-Si; Zeng, Bin; Zhang, Ke-Shi; Zhong, Xian-Ci

2018-02-10

Using copper thin-walled tubular specimens, the subsequent yield surfaces under pre-tension, pre-torsion and pre-combined tension-torsion are measured, where the single-sample and multi-sample methods are applied respectively to determine the yield stresses at specified offset strain. The rule and characteristics of the evolution of the subsequent yield surface are investigated. Under the conditions of different pre-strains, the influence of test point number, test sequence and specified offset strain on the measurement of subsequent yield surface and the concave phenomenon for measured yield surface are studied. Moreover, the feasibility and validity of the two methods are compared. The main conclusions are drawn as follows: (1) For the single or multi-sample method, the measured subsequent yield surfaces are remarkably different from cylindrical yield surfaces proposed by the classical plasticity theory; (2) there are apparent differences between the test results from the two kinds of methods: the multi-sample method is not influenced by the number of test points, test order and the cumulative effect of residual plastic strain resulting from the other test point, while those are very influential in the single-sample method; and (3) the measured subsequent yield surface may appear concave, which can be transformed to convex for single-sample method by changing the test sequence. However, for the multiple-sample method, the concave phenomenon will disappear when a larger offset strain is specified.

Unemployment in Iraqi refugees: The interaction of pre and post-displacement trauma.

PubMed

Wright, A Michelle; Dhalimi, Abir; Lumley, Mark A; Jamil, Hikmet; Pole, Nnamdi; Arnetz, Judith E; Arnetz, Bengt B

2016-12-01

Previous refugee research has been unable to link pre-displacement trauma with unemployment in the host country. The current study assessed the role of pre-displacement trauma, post-displacement trauma, and the interaction of both trauma types to prospectively examine unemployment in a random sample of newly-arrived Iraqi refugees. Participants (N = 286) were interviewed three times over the first two years post-arrival. Refugees were assessed for pre-displacement trauma exposure, post-displacement trauma exposure, a history of unemployment in the country of origin and host country, and symptoms of posttraumatic stress disorder (PTSD) and depression. Analyses found that neither pre-displacement nor post-displacement trauma independently predicted unemployment 2 years post-arrival; however, the interaction of pre and post-displacement trauma predicted 2-year unemployment. Refugees with high levels of both pre and post-displacement trauma had a 91% predicted probability of unemployment, whereas those with low levels of both traumas had a 20% predicted probability. This interaction remained significant after controlling for sociodemographic variables and mental health upon arrival to the US. Resettlement agencies and community organizations should consider the interactive effect of encountering additional trauma after escaping the hardships of the refugee's country of origin. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Morphological evidence for local microcircuits in rat vestibular maculae

NASA Technical Reports Server (NTRS)

Ross, M. D.

1997-01-01

Previous studies suggested that intramacular, unmyelinated segments of vestibular afferent nerve fibers and their large afferent endings (calyces) on type I hair cells branch. Many of the branches (processes) contain vesicles and are presynaptic to type II hair cells, other processes, intramacular nerve fibers, and calyces. This study used serial section transmission electron microscopy and three-dimensional reconstruction methods to document the origins and distributions of presynaptic processes of afferents in the medial part of the adult rat utricular macula. The ultrastructural research focused on presynaptic processes whose origin and termination could be observed in a single micrograph. Results showed that calyces had 1) vesiculated, spine-like processes that invaginated type I cells and 2) other, elongate processes that ended on type II cells pre- as well as postsynaptically. Intramacular, unmyelinated segments of afferent nerve fibers gave origin to branches that were presynaptic to type II cells, calyces, calyceal processes, and other nerve fibers in the macula. Synapses with type II cells occurred opposite subsynaptic cisternae (C synapses); all other synapses were asymmetric. Vesicles were pleomorphic but were differentially distributed according to process origin. Small, clear-centered vesicles, approximately 40-60 nm in diameter, predominated in processes originating from afferent nerve fibers and basal parts of calyces. Larger vesicles approximately 70-120 nm in diameter having approximately 40-80 nm electron-opaque cores were dominant in processes originating from the necks of calyces. Results are interpreted to indicate the existence of a complex system of intrinsic feedforward (postsynaptic)-feedback (presynaptic) connections in a network of direct and local microcircuits. The morphological findings support the concept that maculae dynamically preprocess linear acceleratory information before its transmission to the central nervous system.

The value of integrating pre-clinical data to predict nausea and vomiting risk in humans as illustrated by AZD3514, a novel androgen receptor modulator

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

Grant, Claire, E-mail: claire.grant@astrazeneca.com; Ewart, Lorna; Muthas, Daniel

Nausea and vomiting are components of a complex mechanism that signals food avoidance and protection of the body against the absorption of ingested toxins. This response can also be triggered by pharmaceuticals. Predicting clinical nausea and vomiting liability for pharmaceutical agents based on pre-clinical data can be problematic as no single animal model is a universal predictor. Moreover, efforts to improve models are hampered by the lack of translational animal and human data in the public domain. AZD3514 is a novel, orally-administered compound that inhibits androgen receptor signaling and down-regulates androgen receptor expression. Here we have explored the utility ofmore » integrating data from several pre-clinical models to predict nausea and vomiting in the clinic. Single and repeat doses of AZD3514 resulted in emesis, salivation and gastrointestinal disturbances in the dog, and inhibited gastric emptying in rats after a single dose. AZD3514, at clinically relevant exposures, induced dose-responsive “pica” behaviour in rats after single and multiple daily doses, and induced retching and vomiting behaviour in ferrets after a single dose. We compare these data with the clinical manifestation of nausea and vomiting encountered in patients with castration-resistant prostate cancer receiving AZD3514. Our data reveal a striking relationship between the pre-clinical observations described and the experience of nausea and vomiting in the clinic. In conclusion, the emetic nature of AZD3514 was predicted across a range of pre-clinical models, and the approach presented provides a valuable framework for predicition of clinical nausea and vomiting. - Highlights: • Integrated pre-clinical data can be used to predict clinical nausea and vomiting. • Data integrated from standard toxicology studies is sufficient to make a prediction. • The use of the nausea algorithm developed by Parkinson (2012) aids the prediction. • Additional pre-clinical studies can be used to confirm and quantify the risk.« less

Porous materials with pre-designed single-molecule traps for CO2 selective adsorption

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

Li, JR; Yu, JM; Lu, WG

2013-02-26

Despite tremendous efforts, precise control in the synthesis of porous materials with pre-designed pore properties for desired applications remains challenging. Newly emerged porous metal-organic materials, such as metal-organic polyhedra and metal-organic frameworks, are amenable to design and property tuning, enabling precise control of functionality by accurate design of structures at the molecular level. Here we propose and validate, both experimentally and computationally, a precisely designed cavity, termed a 'single-molecule trap', with the desired size and properties suitable for trapping target CO2 molecules. Such a single-molecule trap can strengthen CO2-host interactions without evoking chemical bonding, thus showing potential for CO2 capture.more » Molecular single-molecule traps in the form of metal-organic polyhedra are designed, synthesised and tested for selective adsorption of CO2 over N-2 and CH4, demonstrating the trapping effect. Building these pre-designed single-molecule traps into extended frameworks yields metal-organic frameworks with efficient mass transfer, whereas the CO2 selective adsorption nature of single-molecule traps is preserved.« less

Fluid modeling of a high-voltage nanosecond pulsed xenon microdischarge

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

Levko, Dmitry; Raja, Laxminarayan L.

2016-07-15

A computational modeling study of high-voltage nanosecond pulsed microdischarge in xenon gas at 10 atm is presented. The discharge is observed to develop as two streamers originating from the cathode and the anode, and propagating toward each other until they merge to form a single continuous discharge channel. The peak plasma density obtained in the simulations is ∼10{sup 24 }m{sup −3}, i.e., the ionization degree of plasma does not exceed 1%. The influence of the initial gas pre-ionization is established. It is seen that an increase in the seeded plasma density results in an increase in the streamer propagation velocity andmore » an increase in the plasma density obtained after the merging of two streamers.« less

Evaluation of a novel triple-channel radiochromic film analysis procedure using EBT2.

PubMed

van Hoof, Stefan J; Granton, Patrick V; Landry, Guillaume; Podesta, Mark; Verhaegen, Frank

2012-07-07

A novel approach to read out radiochromic film was introduced recently by the manufacturer of GafChromic film. In this study, the performance of this triple-channel film dosimetry method was compared against the conventional single-red-channel film dosimetry procedure, with and without inclusion of a pre-irradiation (pre-IR) film scan, using EBT2 film and kilo- and megavoltage photon beams up to 10 Gy. When considering regions of interest averaged doses, the triple-channel method and both single-channel methods produced equivalent results. Absolute dose discrepancies between the triple-channel method, both single-channel methods and the treatment planning system calculated dose values, were no larger than 5 cGy for dose levels up to 2.2 Gy. Signal to noise in triple-channel dose images was found to be similar to signal to noise in single-channel dose images. The accuracy of resulting dose images from the triple- and single-channel methods with inclusion of pre-IR film scan was found to be similar. Results of a comparison of EBT2 data from a kilovoltage depth dose experiment to corresponding Monte Carlo depth dose data produced dose discrepancies of 9.5 ± 12 cGy and 7.6 ± 6 cGy for the single-channel method with inclusion of a pre-IR film scan and the triple-channel method, respectively. EBT2 showed to be energy sensitive at low kilovoltage energies with response differences of 11.9% and 15.6% in the red channel at 2 Gy between 50-225 kVp and 80-225 kVp photon spectra, respectively. We observed that the triple-channel method resulted in non-uniformity corrections of ±1% and consistency values of 0-3 cGy for the batches and dose levels studied. Results of this study indicate that the triple-channel radiochromic film read-out method performs at least as well as the single-channel method with inclusion of a pre-IR film scan, reduces film non-uniformity and saves time with elimination of a pre-IR film scan.

Use of the Single Particle Soot Photometer (SP2) as a pre-filter for ice nucleation measurements: effect of particle mixing state and determination of SP2 conditions to fully vaporize refractory black carbon

NASA Astrophysics Data System (ADS)

Schill, Gregory P.; DeMott, Paul J.; Levin, Ezra J. T.; Kreidenweis, Sonia M.

2018-05-01

Ice nucleation is a fundamental atmospheric process that impacts precipitation, cloud lifetimes, and climate. Challenges remain to identify and quantify the compositions and sources of ice-nucleating particles (INPs). Assessment of the role of black carbon (BC) as an INP is particularly important due to its anthropogenic sources and abundance at upper-tropospheric cloud levels. The role of BC as an INP, however, is unclear. This is, in part, driven by a lack of techniques that directly determine the contribution of refractory BC (rBC) to INP concentrations. One previously developed technique to measure this contribution uses the Single Particle Soot Photometer (SP2) as a pre-filter to an online ice-nucleating particle counter. In this technique, rBC particles are selectively heated to their vaporization temperature in the SP2 cavity by a 1064 nm laser. From previous work, however, it is unclear under what SP2 conditions, if any, the original rBC particles were fully vaporized. Furthermore, previous work also left questions about the effect of the SP2 laser on the ice-nucleating properties of several INP proxies and their mixtures with rBC.To answer these questions, we sampled the exhaust of an SP2 with a Scanning Mobility Particle Sizer and a Continuous Flow Diffusion Chamber. Using Aquadag® as an rBC proxy, the effect of several SP2 instrument parameters on the size distribution and physical properties of particles in rBC SP2 exhaust were explored. We found that a high SP2 laser power (930 nW/(220 nm PSL)) is required to fully vaporize a ˜ 0.76 fg rBC particle. We also found that the exhaust particle size distribution is minimally affected by the SP2 sheath-to-sample ratio; the size of the original rBC particle, however, greatly influences the size distribution of the SP2 exhaust. The effect of the SP2 laser on the ice nucleation efficiency of Snomax®, NX-illite, and Suwannee River Fulvic Acid was studied; these particles acted as proxies for biological, illite-rich mineral dust, and brown carbon INPs, respectively. The original size distribution and ice nucleation efficiency of all non-rBC proxies were unaffected by the SP2 laser. Furthermore, the ice nucleation efficiencies of all proxies were not affected when externally mixed with rBC. These proxies, however, always show a reduction in ice-nucleating ability when internally mixed with rBC. We end this work with recommendations for users who wish to use the SP2 as a pre-filter to remove large rBC particles from an aerosol stream.

Prereplicative complexes assembled in vitro support origin-dependent and independent DNA replication

PubMed Central

On, Kin Fan; Beuron, Fabienne; Frith, David; Snijders, Ambrosius P; Morris, Edward P; Diffley, John F X

2014-01-01

Eukaryotic DNA replication initiates from multiple replication origins. To ensure each origin fires just once per cell cycle, initiation is divided into two biochemically discrete steps: the Mcm2-7 helicase is first loaded into prereplicative complexes (pre-RCs) as an inactive double hexamer by the origin recognition complex (ORC), Cdt1 and Cdc6; the helicase is then activated by a set of “firing factors.” Here, we show that plasmids containing pre-RCs assembled with purified proteins support complete and semi-conservative replication in extracts from budding yeast cells overexpressing firing factors. Replication requires cyclin-dependent kinase (CDK) and Dbf4-dependent kinase (DDK). DDK phosphorylation of Mcm2-7 does not by itself promote separation of the double hexamer, but is required for the recruitment of firing factors and replisome components in the extract. Plasmid replication does not require a functional replication origin; however, in the presence of competitor DNA and limiting ORC concentrations, replication becomes origin-dependent in this system. These experiments indicate that Mcm2-7 double hexamers can be precursors of replication and provide insight into the nature of eukaryotic DNA replication origins. PMID:24566989

Pre-procedural antibiotics for endoscopic urological procedures: Initial experience in individuals with spinal cord injury and asymptomatic bacteriuria.

PubMed

Chong, Julio T; Klausner, Adam P; Petrossian, Albert; Byrne, Michael D; Moore, Jewel R; Goetz, Lance L; Gater, David R; Grob, B Mayer

2015-03-01

The objective of this study was to compare the safety, efficacy, quality-of-life impact, and costs of a single dose or a longer course of pre-procedural antibiotics prior to elective endoscopic urological procedures in individuals with spinal cord injury and disorders (SCI/D) and asymptomatic bacteriuria. A prospective observational study. Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, Virginia, USA. Sixty persons with SCI/D and asymptomatic bacteriuria scheduled to undergo elective endoscopic urological procedures. A single pre-procedural dose of antibiotics vs. a 3-5-day course of pre-procedural antibiotics. Objective and subjective measures of health, costs, and quality of life. There were no significant differences in vital signs, leukocytosis, adverse events, and overall satisfaction in individuals who received short-course vs. long-course antibiotics. There was a significant decrease in antibiotic cost (33.1 ± 47.6 vs. 3.6 ± 6.1 US$, P = 0.01) for individuals in the short-course group. In addition, there was greater pre-procedural anxiety (18 vs. 0%, P < 0.05) for individuals who received long-course antibiotics. SCI/D individuals with asymptomatic bacteriuria may be able to safely undergo most endoscopic urological procedures with a single dose of pre-procedural antibiotics. However, further research is required and even appropriate pre-procedural antibiotics may not prevent severe infections.

Profiling Pre-MicroRNA and Mature MicroRNA Expressions Using a Single Microarray and Avoiding Separate Sample Preparation

PubMed Central

Gan, Lin; Denecke, Bernd

2013-01-01

Mature microRNA is a crucial component in the gene expression regulation network. At the same time, microRNA gene expression and procession is regulated in a precise and collaborated way. Pre-microRNAs mediate products during the microRNA transcription process, they can provide hints of microRNA gene expression regulation or can serve as alternative biomarkers. To date, little effort has been devoted to pre-microRNA expression profiling. In this study, three human and three mouse microRNA profile data sets, based on the Affymetrix miRNA 2.0 array, have been re-analyzed for both mature and pre-microRNA signals as a primary test of parallel mature/pre-microRNA expression profiling on a single platform. The results not only demonstrated a glimpse of pre-microRNA expression in human and mouse, but also the relationship of microRNA expressions between pre- and mature forms. The study also showed a possible application of currently available microRNA microarrays in profiling pre-microRNA expression in a time and cost effective manner. PMID:27605179

Next-generation sequencing traces human induced pluripotent stem cell lines clonally generated from heterogeneous cancer tissue.

PubMed

Ishikawa, Tetsuya

2017-05-26

To investigate genotype variation among induced pluripotent stem cell (iPSC) lines that were clonally generated from heterogeneous colon cancer tissues using next-generation sequencing. Human iPSC lines were clonally established by selecting independent single colonies expanded from heterogeneous primary cells of S-shaped colon cancer tissues by retroviral gene transfer ( OCT3/4 , SOX2 , and KLF4 ). The ten iPSC lines, their starting cancer tissues, and the matched adjacent non-cancerous tissues were analyzed using next-generation sequencing and bioinformatics analysis using the human reference genome hg19. Non-synonymous single-nucleotide variants (SNVs) (missense, nonsense, and read-through) were identified within the target region of 612 genes related to cancer and the human kinome. All SNVs were annotated using dbSNP135, CCDS, RefSeq, GENCODE, and 1000 Genomes. The SNVs of the iPSC lines were compared with the genotypes of the cancerous and non-cancerous tissues. The putative genotypes were validated using allelic depth and genotype quality. For final confirmation, mutated genotypes were manually curated using the Integrative Genomics Viewer. In eight of the ten iPSC lines, one or two non-synonymous SNVs in EIF2AK2 , TTN , ULK4 , TSSK1B , FLT4 , STK19 , STK31 , TRRAP , WNK1 , PLK1 or PIK3R5 were identified as novel SNVs and were not identical to the genotypes found in the cancer and non-cancerous tissues. This result suggests that the SNVs were de novo or pre-existing mutations that originated from minor populations, such as multifocal pre-cancer (stem) cells or pre-metastatic cancer cells from multiple, different clonal evolutions, present within the heterogeneous cancer tissue. The genotypes of all ten iPSC lines were different from the mutated ERBB2 and MKNK2 genotypes of the cancer tissues and were identical to those of the non-cancerous tissues and that found in the human reference genome hg19. Furthermore, two of the ten iPSC lines did not have any confirmed mutated genotypes, despite being derived from cancerous tissue. These results suggest that the traceability and preference of the starting single cells being derived from pre-cancer (stem) cells, stroma cells such as cancer-associated fibroblasts, and immune cells that co-existed in the tissues along with the mature cancer cells. The genotypes of iPSC lines derived from heterogeneous cancer tissues can provide information on the type of starting cell that the iPSC line was generated from.

Impact of ozonation and biological activated carbon filtration on ceramic membrane fouling.

PubMed

Ibn Abdul Hamid, Khaled; Sanciolo, Peter; Gray, Stephen; Duke, Mikel; Muthukumaran, Shobha

2017-12-01

Ozone pre-treatment (ozonation, ozonisation) and biological activated carbon (BAC) filtration pre-treatment for the ceramic microfiltration (CMF) treatment of secondary effluent (SE) were studied. Ozone pre-treatment was found to result in higher overall removal of UV absorbance (UVA 254 ) and colour, and higher permeability than BAC pre-treatment or the combined use of ozone and BAC (O3+BAC) pre-treatment. The overall removal of colour and UVA 254 by ceramic filtration of the ozone pre-treated water was 97% and 63% respectively, compared to 86% and 48% respectively for BAC pre-treatment and 29% and 6% respectively for the untreated water. Ozone pre-treatment, however, was not effective in removal of dissolved organic carbon (DOC). The permeability of the ozone pre-treated water through the ceramic membrane was found to decrease to 50% of the original value after 200 min of operation, compared to approximately 10% of the original value for the BAC pre-treated, O3+BAC pre-treated water and the untreated water. The higher permeability of the ozone pre-treated water was attributed to the excellent removal of biopolymer particles (100%) and high removal of humic substances (84%). The inclusion of a BAC stage between ozone pre-treatment and ceramic filtration was detrimental. The O3+BAC+CMF process was found to yield higher biopolymer removal (96%), lower humic substance (HS) component removal (66%) and lower normalized permeability (0.1) after 200 min of operation than the O3+CMF process (86%, 84% and 0.5 respectively). This was tentatively attributed to the chemical oxidation effect of ozone on the BAC biofilm and adsorbed components, leading to the generation of foulants that are not generated in the O3+CMF process. This study demonstrated the potential of ozone pre-treatment for reducing organic fouling and thus improving flux for the CMF of SE compared to O3+BAC pre-treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Single-Molecule Analysis of Pre-mRNA Splicing with Colocalization Single-Molecule Spectroscopy (CoSMoS).

PubMed

Braun, Joerg E; Serebrov, Victor

2017-01-01

Recent development of single-molecule techniques to study pre-mRNA splicing has provided insights into the dynamic nature of the spliceosome. Colocalization single-molecule spectroscopy (CoSMoS) allows following spliceosome assembly in real time at single-molecule resolution in the full complexity of cellular extracts. A detailed protocol of CoSMoS has been published previously (Anderson and Hoskins, Methods Mol Biol 1126:217-241, 2014). Here, we provide an update on the technical advances since the first CoSMoS studies including slide surface treatment, data processing, and representation. We describe various labeling strategies to generate RNA reporters with multiple dyes (or other moieties) at specific locations.

Evidence from the northwestern Venezuelan Andes for extraterrestrial impact: The black mat enigma

NASA Astrophysics Data System (ADS)

Mahaney, W. C.; Kalm, V.; Krinsley, D. H.; Tricart, P.; Schwartz, S.; Dohm, J.; Kim, K. J.; Kapran, B.; Milner, M. W.; Beukens, R.; Boccia, S.; Hancock, R. G. V.; Hart, K. M.; Kelleher, B.

2010-03-01

A carbon-rich black layer encrusted on a sandy pebbly bed of outwash in the northern Venezuelan Andes, previously considered the result of an alpine grass fire, is now recognized as a 'black mat' candidate correlative with Clovis Age sites in North America, falling within the range of 'black mat' dated sites (~ 12.9 ka cal BP). As such, the bed at site MUM7B, which dates to < 11.8 ka 14C years BP (raw dates) and appears to be contemporaneous with the Younger Dryas (YD) cooling event, marks a possibly much more extensive occurrence than previously identified. No fossils (megafauna) or tool assemblages were observed at this newly identified candidate site (3800 a.m.s.l.), as in the case of the North American sites. Here, evidence is presented for an extraterrestrial impact event at ~ 12.9 ka. The impact-related Andean bed, located ~ 20 cm above 13.7-13.3 ka cal BP alluvial and glaciolacustrine deposits, falls within the sediment characteristics and age range of 'black mat' dated sites (~ 12.9 ka cal BP) in North America. Site sediment characteristics include: carbon, glassy spherules, magnetic microspherules, carbon mat 'welded' onto coarse granular material, occasional presence of platinum group metals (Rh and Ru), planar deformation features (pdfs) in fine silt-size fragmental grains of quartz, as well as orthoclase, and monazite (with an abundance of Rare Earth Elements—REEs). If the candidate site is 'black mat', correlative with the 'black mat' sites of North America, such an extensive occurrence may support the hypothesized airburst/impact over the Laurentide Glacier, which led to a reversal of Allerød warming and the onset of YD cooling and readvance of glaciers. While this finding does not confirm such, it merits further investigation, which includes the reconnaissance for additional sites in South America. Furthermore, if confirmed, such an extensive occurrence may corroborate an impact origin.

The Ryan/Harley site: Sedimentology of an inundated Paleoindian site in north Florida

USGS Publications Warehouse

Balsillie, J.H.; Means, G.H.; Dunbar, J.S.

2006-01-01

The Ryan/Harley site (Florida Master Site File Number: 8Je-1004) is a Middle Paleoindian habitation site containing Suwannee points. Based on stratigraphic correlation and diagnostic artifact seriation, Suwannee-age sites have been relatively dated from ??? 10,900 14C yr B.P to ??? 10,500 14C yr B.P. Clovis-like traits on the Suwannee points and other stone tools from the Ryan/Harley site suggest it dates to the earlier end of the Suwannee timeframe. The currently inundated site is partially buried beneath a sediment column located in a swamp forest and partially exposed in a side channel section of the Wacissa River, Jefferson County, Florida. Research done prior to this analysis determined that the artifact assemblage appeared to be unsorted and was contained in a midden-like unit. Our purpose here is to assess the issue of site integrity further. Unconsolidated sediment samples collected from the artifact-bearing horizon and from horizons immediately above and below the artifact horizon were analyzed using granulometric techniques. Arithmetic probability plots of the grain-size distributions show that the sediments were transported and deposited by fluvial processes. Thus, the Suwannee points and associated artifacts, and faunal remains appear to have accumulated during a time of subaerial exposure perhaps after a regional water-table decline, and have remained largely or essentially intact, with little or no postdepositional reworking. The artifacts and faunal remains recovered from the artifact-bearing horizon at Ryan/Harley are distributed randomly, showing no sign of sorting. In the fossil suite, two articulated white-tailed deer (Odocoileus virginianus) vertebra were recovered in situ. The unsorted nature of artifacts and articulated faunal remains that are contained within the fluvially deposited sediments suggests the Suwannee point level of the Ryan/Harley site has remained undisturbed since original deposition. ?? 2006 Wiley Periodicals, Inc.

Genome-wide mapping reveals single-origin chromosome replication in Leishmania, a eukaryotic microbe.

PubMed

Marques, Catarina A; Dickens, Nicholas J; Paape, Daniel; Campbell, Samantha J; McCulloch, Richard

2015-10-19

DNA replication initiates on defined genome sites, termed origins. Origin usage appears to follow common rules in the eukaryotic organisms examined to date: all chromosomes are replicated from multiple origins, which display variations in firing efficiency and are selected from a larger pool of potential origins. To ask if these features of DNA replication are true of all eukaryotes, we describe genome-wide origin mapping in the parasite Leishmania. Origin mapping in Leishmania suggests a striking divergence in origin usage relative to characterized eukaryotes, since each chromosome appears to be replicated from a single origin. By comparing two species of Leishmania, we find evidence that such origin singularity is maintained in the face of chromosome fusion or fission events during evolution. Mapping Leishmania origins suggests that all origins fire with equal efficiency, and that the genomic sites occupied by origins differ from related non-origins sites. Finally, we provide evidence that origin location in Leishmania displays striking conservation with Trypanosoma brucei, despite the latter parasite replicating its chromosomes from multiple, variable strength origins. The demonstration of chromosome replication for a single origin in Leishmania, a microbial eukaryote, has implications for the evolution of origin multiplicity and associated controls, and may explain the pervasive aneuploidy that characterizes Leishmania chromosome architecture.

Fluorescence Resonance Energy Transfer-Based Photonic Circuits Using Single-Stranded Tile Self-Assembly and DNA Strand Displacement.

PubMed

Zhang, Xuncai; Ying, Niu; Shen, Chaonan; Cui, Guangzhao

2017-02-01

Structural DNA nanotechnology has great potential in the fabrication of complicated nanostructures and devices capable of bio-sensing and logic function. A variety of nanostructures with desired shapes have been created in the past few decades. But the application of nanostructures remains to be fully studied. Here, we present a novel biological information processing system constructed on a self-assembled, spatially addressable single-stranded tile (SST) nanostructure as DNA nano-manipulation platform that created by SST self-assembly technology. Utilizing DNA strand displacement technology, the fluorescent dye that is pre-assembled in the nano-manipulation platform is transferred from the original position to the destination, which can achieve photonic logic circuits by FRET signal cascades, including logic AND, OR, and NOT gates. And this transfer process is successfully validated by visual DSD software. The transfer process proposed in this study may provide a novel method to design complicated biological information processing system constructed on a SST nanostructure, and can be further used to develop intelligent delivery of drug molecules in vivo.

Xenopus origin recognition complex (ORC) initiates DNA replication preferentially at sequences targeted by Schizosaccharomyces pombe ORC

PubMed Central

Kong, Daochun; Coleman, Thomas R.; DePamphilis, Melvin L.

2003-01-01

Budding yeast (Saccharomyces cerevisiae) origin recognition complex (ORC) requires ATP to bind specific DNA sequences, whereas fission yeast (Schizosaccharomyces pombe) ORC binds to specific, asymmetric A:T-rich sites within replication origins, independently of ATP, and frog (Xenopus laevis) ORC seems to bind DNA non-specifically. Here we show that despite these differences, ORCs are functionally conserved. Firstly, SpOrc1, SpOrc4 and SpOrc5, like those from other eukaryotes, bound ATP and exhibited ATPase activity, suggesting that ATP is required for pre-replication complex (pre-RC) assembly rather than origin specificity. Secondly, SpOrc4, which is solely responsible for binding SpORC to DNA, inhibited up to 70% of XlORC-dependent DNA replication in Xenopus egg extract by preventing XlORC from binding to chromatin and assembling pre-RCs. Chromatin-bound SpOrc4 was located at AT-rich sequences. XlORC in egg extract bound preferentially to asymmetric A:T-sequences in either bare DNA or in sperm chromatin, and it recruited XlCdc6 and XlMcm proteins to these sequences. These results reveal that XlORC initiates DNA replication preferentially at the same or similar sites to those targeted in S.pombe. PMID:12840006

Comparative assessment of laparoscopic single-site surgery instruments to conventional laparoscopic in laboratory setting.

PubMed

Stolzenburg, Jens-Uwe; Kallidonis, Panagiotis; Oh, Min-A; Ghulam, Nabi; Do, Minh; Haefner, Tim; Dietel, Anja; Till, Holger; Sakellaropoulos, George; Liatsikos, Evangelos N

2010-02-01

Laparoendoscopic single-site surgery (LESS) represents the latest innovation in laparoscopic surgery. We compare in dry and animal laboratory the efficacy of recently introduced pre-bent instruments with conventional laparoscopic and flexible instruments in terms of time requirement, maneuverability, and ease of handling. Participants of varying laparoscopic experience were included in the study and divided in groups according to their experience. The participants performed predetermined tasks in dry laboratory using all sets of instruments. An experienced laparoscopic surgeon performed 24 nephrectomies in 12 pigs using all sets of instruments. Single port was used for all instrument sets except for the conventional instruments, which were inserted through three ports. The time required for the performance of dry laboratory tasks and the porcine nephrectomies was recorded. Errors in the performance of dry laboratory tasks of each instrument type were also recorded. Pre-bent instruments had a significant advantage over flexible instruments in terms of time requirement to accomplish tasks and procedures as well as maneuverability. Flexible instruments were more time consuming in comparison to the conventional laparoscopic instruments during the performance of the tasks. There were no significant differences in the time required for the accomplishment of dry laboratory tasks or steps of nephrectomy using conventional instruments through appropriate number of ports in comparison to pre-bent instruments through single port. Pre-bent instruments were less time consuming and with better maneuverability in comparison to flexible instruments in experimental single-port access surgery. Further clinical investigations would elucidate the efficacy of pre-bent instruments.

Using optical tweezers to relate the chemical and mechanical cross-bridge cycles.

PubMed

Steffen, Walter; Sleep, John

2004-12-29

In most current models of muscle contraction there are two translational steps, the working stroke, whereby an attached myosin cross-bridge moves relative to the actin filament, and the repriming step, in which the cross-bridge returns to its original orientation. The development of single molecule methods has allowed a more detailed investigation of the relationship of these mechanical steps to the underlying biochemistry. In the normal adenosine triphosphate cycle, myosin.adenosine diphosphate.phosphate (M.ADP.Pi) binds to actin and moves it by ca. 5 nm on average before the formation of the end product, the rigor actomyosin state. All the other product-like intermediate states tested were found to give no net movement indicating that M.ADP.Pi alone binds in a pre-force state. Myosin states with bound, unhydrolysed nucleoside triphosphates also give no net movement, indicating that these must also bind in a post-force conformation and that the repriming, post- to pre-transition during the forward cycle must take place while the myosin is dissociated from actin. These observations fit in well with the structural model in which the working stroke is aligned to the opening of the switch 2 element of the ATPase site.

Review of pre-rift continental fits and plate kinematic models for the Gulf of Mexico opening

NASA Astrophysics Data System (ADS)

Steier, A.; Mann, P.

2016-12-01

We review models for the opening of the Gulf of Mexico (GOM) by: 1) subdividing them into historical groupings; 2) demonstrating their strengths and weaknesses using GPlates; and 3) illustrating the compatibility of models for GOM opening with the surrounding plate mosaic in the Central Atlantic and Caribbean. Tectonic models for GOM opening during the 1970's and 1980's disagreed on whether the Yucatan continental block originated inside or outside the GOM, but difficulties in filling the continental underlap in reconstructions of pre-rift Pangea eventually led to a consensus that the Yucatan block originated inside the GOM. The 1980's saw the advent of the "piggyback model" for GOM evolution based on the assumption that the Jurassic opening of the GOM formed a southwestward extension of the Central Atlantic spreading system and opened about its same pole of rotation. This single-phase model eventually fell out of favor as refraction surveys determined that the existence of a wedge-shaped area of oceanic crust in the deep GOM (widening from east to west) was not compatible with the single, NW-SE opening direction proposed by the piggyback model. The early 2000's saw the appearance of a two-phase opening model as a solution to the existence of a broad zone of NW-SE continental extension in the northern GOM that was succeeded by a more NS-directed phase of extension that in some areas cut at right angles across structures produced during the first rift phase. The second phase of late Jurassic rifting and oceanic crust formation is the outcome of counterclockwise rotation of the Yucatan block that is thought to have been caused by forces acting on the edges of the block. By the earliest Cretaceous rifting in the GOM has ended although tectonic events in Mexico and the northern Caribbean reactivate and influence GOM sedimentation. We provide a GPlates restoration from Triassic to Recent that takes into account all available geologic and geophysical data and illustrates the two-phase GOM opening model which appears to be the tectonic model that can explain the most geologic and geophysical datasets from the Caribbean.

Methods for Producing High-Performance Silicon Carbide Fibers, Architectural Preforms, and High-Temperature Composite Structures

NASA Technical Reports Server (NTRS)

Yun, Hee-Mann (Inventor); DiCarlo, James A. (Inventor)

2014-01-01

Methods are disclosed for producing architectural preforms and high-temperature composite structures containing high-strength ceramic fibers with reduced preforming stresses within each fiber, with an in-situ grown coating on each fiber surface, with reduced boron within the bulk of each fiber, and with improved tensile creep and rupture resistance properties tier each fiber. The methods include the steps of preparing an original sample of a preform formed from a pre-selected high-strength silicon carbide ceramic fiber type, placing the original sample in a processing furnace under a pre-selected preforming stress state and thermally treating the sample in the processing furnace at a pre-selected processing temperature and hold time in a processing gas having a pre-selected composition, pressure, and flow rate. For the high-temperature composite structures, the method includes additional steps of depositing a thin interphase coating on the surface of each fiber and forming a ceramic or carbon-based matrix within the sample.

Is Exercise Stress Testing a Cost-Saving Strategy For Risk Assessment of Pediatric Wolff-Parkinson-White Syndrome Patients?

PubMed Central

Moltedo, Jose M.; Iyer, Ramesh V.; Forman, Howard; Fahey, John; Rosenthal, Geoffrey; Snyder, Christopher S.

2006-01-01

Background: In Wolff-Parkinson-White syndrome (WPW) patients the loss of pre-excitation in a single heartbeat during exercise stress testing (EST) is a predictor of low risk of sudden death. The purpose of this study was to: 1) assess the frequency of loss of pre-excitation in a single heartbeat during exercise testing, and 2) compare the cost of EST versus trans-catheter electrophysiology study (EPS) in the risk assessment of WPW patients. Methods: A retrospective review of 50 cases of patients with WPW who underwent EST was conducted including demographics, history of supraventricular tachycardia, associated congenital heart disease, maximum heart rate achieved, and loss of pre-excitation in a single heartbeat. Hospital costs of EST and EPS were compared. Results: Of the 50 patients who underwent EST, 4 (8%), lost pre-excitation in a single heartbeat during EST. No differences were found regarding gender, age at diagnosis or EST, history of supraventricular tachycardia, presence of congenital heart disease or maximal heart rate. A cost comparison, utilizing the cost data: EST ($62.75) and EPS ($5,597) found EST to be a cost-saving approach in WPW patients. With 4 patients losing pre-excitation during EST, the cost saving of EST was $22,388 for this population of WPW patients. Conclusions: A frequency of 8% loss of pre-excitation was found in a pediatric sample that underwent EST. Additionally, EST was shown to be a cost-saving strategy in risk assessment of pediatric WPW patients. PMID:21845141

Our Year of Dissonance: Teacher Identity and the Transition to Teaching Pre-K

ERIC Educational Resources Information Center

Delaney, Katherine K.

2014-01-01

This dissertation is a single case study of a teacher, Wanda, transitioning from teaching Kindergarten to teaching pre-K. A veteran public school Kindergarten teacher with more than ten years experience, Wanda saw teaching pre-K as an opportunity for professional growth and development. Wanda's transition to teaching pre-K was also a transition…

The Pre-K Debates: Current Controversies and Issues

ERIC Educational Resources Information Center

Zigler, Edward, Ed.; Gilliam, Walter S., Ed.; Barnett, W. Steven, Ed.

2011-01-01

Targeted or universal pre-K? Direct instruction or learning through play? These and other debates are heating up as more and more young children across the country gain access to pre-K programs. Now there's a single volume that spotlights today's most urgent pre-K debates, explores each one from all sides, and paves the way for sound, educated…

Latino Immigrants’ Biological Parents’ Histories Of Substance Use Problems In Their Country Of Origin Predict Their Pre- And Post-Immigration Alcohol Use Problems

PubMed Central

Blackson, Timothy C.; De La Rosa, Mario; Sanchez, Mariana; Li, Tan

2014-01-01

Background No studies to date have assessed whether recent young adult (ages 18–34) Latino immigrants’ biological parents’ histories of substance use problems (BPHSUP) in their country of origin predict their alcohol use problems at pre- and post-immigration to the United States (U.S.). Methods BPHSUP in their country of origin was assessed via interviews conducted by bilingual Latino researchers with recent Latino immigrants primarily from Cuba, Central and South America recruited through respondent driven sampling at the time of their immigration to southeastern U.S. Three-waves of data were collected to document Latino immigrants’ severity of alcohol use problems at pre-immigration and two annual post-immigration follow-up assessments. BPHSUP +/− status was used as a predictor of Latinos’ (N=452; 45.8% female, 54.2% male) Alcohol Use Disorders Identification Test (AUDIT) scores at pre- and post-immigration with age, education and income as covariates as wells as odds ratios for AUDIT classifications of hazardous use, harmful use and dependence. Results BPHSUP+ status predicted Latino immigrants’ higher AUDIT scores pre- and post-immigration by gender (p<.01) compared to Latino immigrants of BPHSUP− status controlling for age, education and income. BPHSUP+ status predicted odds ratios of 3.45 and 2.91 for alcohol dependence AUDIT classification for men and women respectively (T3). Conclusions This study documents that BPHSUP +/− status in their country of origin predict their young adult Latino offspring’s severity of alcohol use problems pre-and post-immigration. These results may inform (1) community-based health care providers to screen recent young adult Latino immigrants for their BPHSUP+/− status and severity of alcohol use problems to redirect trajectories away from alcohol use disorders toward more normative post-immigration outcomes through culturally relevant prevention services and (2) future research advantages of differential susceptibility theory. Implications for future research and the need for replication studies in other geographic regions of the U.S. are discussed. PMID:24960302

PEG spacer gel and adaptive planning vs single plan in external prostate radiotherapy—clinical dosimetry evaluation

PubMed Central

2015-01-01

Objective: Spacer gel is used to reduce the rectal dose in prostate radiotherapy. It is injected to increase the distance between the prostate and rectum. During the course of external radiotherapy treatment, physiological changes in rectal volume exist. When using polyethylene glycol material, such as DuraSeal® (Covidien, Mansfield, MA), gel resorption also occurs. Together, these factors alter the original dose plan distribution. Methods: External dose planning and calculations were simulated using images acquired from 10 patients who were treated with brachytherapy and gel. The CT series was taken relative to gel injection: pre 1 day, post 1 day, post 1 month and post 2 months. Adaptive planning was compared with a single plan. Results: Adaptive planning shows better results compared with the single plan used in the total treatment course; however, the effect is minor. Conclusion: Gel usage is clearly favourable to rectal DVH. Using adaptive planning with gel improves rectal DVH but is not necessary according to this study. Advances in knowledge: Spacer gel is used in prostate radiotherapy to increase distance between the prostate and the rectum, thus reducing the rectal doses. During the treatment course, gel resorption exists which affects the rectal doses. The usefulness of adaptive planning to compensate this resorption effect has not been studied before. PMID:26370300

Adiposity and hyperglycaemia in pregnancy and related health outcomes in European ethnic minorities of Asian and African origin: a review

PubMed Central

Jenum, Anne Karen; Sommer, Christine; Sletner, Line; Mørkrid, Kjersti; Bærug, Anne; Mosdøl, Annhild

2013-01-01

Background Ethnic minorities in Europe have high susceptibility to type 2 diabetes (T2DM) and, in some groups, also cardiovascular disease (CVD). Pregnancy can be considered a stress test that predicts future morbidity patterns in women and that affects future health of the child. Objective To review ethnic differences in: 1) adiposity, hyperglycaemia, and pre-eclampsia during pregnancy; 2) future risk in the mother of obesity, T2DM and CVD; and 3) prenatal development and possible influences of maternal obesity, hyperglycaemia, and pre-eclampsia on offspring's future disease risk, as relevant for ethnic minorities in Europe of Asian and African origin. Design Literature review. Results Maternal health among ethnic minorities is still sparsely documented. Higher pre-pregnant body mass index (BMI) is found in women of African and Middle Eastern descent, and lower BMI in women from East and South Asia compared with women from the majority population. Within study populations, risk of gestational diabetes mellitus (GDM) is considerably higher in many minority groups, particularly South Asians, than in the majority population. This increased risk is apparent at lower BMI and younger ages. Women of African origin have higher risk of pre-eclampsia. A GDM pregnancy implies approximately seven-fold higher risk of T2DM than normal pregnancies, and both GDM and pre-eclampsia increase later risk of CVD. Asian neonates have lower birth weights, and mostly also African neonates. This may translate into increased risks of later obesity, T2DM, and CVD. Foetal overgrowth can promote the same conditions. Breastfeeding represents a possible strategy to reduce risk of T2DM in both the mother and the child. Conclusions Ethnic minority women in Europe with Asian and African origin and their offspring seem to be at increased risk of T2DM and CVD, both currently and in the future. Pregnancy is an important window of opportunity for short and long-term disease prevention. PMID:23467680

Effects of the Original Versus Revised Bloom's Taxonomy on Lesson Planning Skills: A Turkish Study Among Pre-Service Teachers

NASA Astrophysics Data System (ADS)

Bümen, Nilay T.

2007-07-01

The original taxonomy of educational objectives, developed by Benjamin S.␣Bloom and his associates in the 1950s, was revised several decades later by a group of educationists and cognitive psychologists, who developed a revised taxonomy (RT). This article describes a Turkish study carried out among a group of pre-service teachers in order to compare the influence of the two systems on lesson planning skills. The results confirmed other studies that have indicated a number of advantages of the revised system over the earlier one.

Universal Temporal Profile of Replication Origin Activation in Eukaryotes

NASA Astrophysics Data System (ADS)

Goldar, Arach

2011-03-01

The complete and faithful transmission of eukaryotic genome to daughter cells involves the timely duplication of mother cell's DNA. DNA replication starts at multiple chromosomal positions called replication origin. From each activated replication origin two replication forks progress in opposite direction and duplicate the mother cell's DNA. While it is widely accepted that in eukaryotic organisms replication origins are activated in a stochastic manner, little is known on the sources of the observed stochasticity. It is often associated to the population variability to enter S phase. We extract from a growing Saccharomyces cerevisiae population the average rate of origin activation in a single cell by combining single molecule measurements and a numerical deconvolution technique. We show that the temporal profile of the rate of origin activation in a single cell is similar to the one extracted from a replicating cell population. Taking into account this observation we exclude the population variability as the origin of observed stochasticity in origin activation. We confirm that the rate of origin activation increases in the early stage of S phase and decreases at the latter stage. The population average activation rate extracted from single molecule analysis is in prefect accordance with the activation rate extracted from published micro-array data, confirming therefore the homogeneity and genome scale invariance of dynamic of replication process. All these observations point toward a possible role of replication fork to control the rate of origin activation.

The Impact of Origin and Host Country Schooling on the Economic Performance of Immigrants

ERIC Educational Resources Information Center

Kanas, Agnieszka; van Tubergen, Frank

2009-01-01

This study examines the economic returns to schooling acquired in the country of origin and the country of destination. It uses large-scale survey data on Turkish, Moroccan, Surinamese and Antillean immigrants in the Netherlands, which contain direct measures of pre- and post migration schooling. It is studied whether the returns to origin-country…

The Effect of Learning the History of Physics on the Scientific Epistemological Beliefs of Pre-Service Teachers

ERIC Educational Resources Information Center

Tanel, Zafer

2013-01-01

This study examined the effect of learning the history of physics on the epistemological beliefs of pre-service physics teachers. The research was conducted with 25 pre-service physics teachers using a single-group pre-test/post-test experimental model. The quantitative data of the research were collected using the Turkish version of the…

Lunar crater arcs. [origins, distribution and age classification of Pre-Imbrian families

NASA Technical Reports Server (NTRS)

Jaffe, L. D.; Bulkley, E. O.

1976-01-01

An analysis has been made of the tendency of large lunar craters to lie along circles. A catalog of the craters at least 50 km in diameter was prepared first, noting position, diameter, rim sharpness and completion, nature of underlying surface, and geological age. The subset of those craters 50-400 km in diameter was then used as input to computer programs which identified each 'family' of four or more craters of selected geological age lying on a circular arc. For comparison, families were also identified for randomized crater models in which the crater spatial density was matched to that on the moon, either overall or separately for mare and highland areas. The observed frequency of lunar arcuate families was statistically highly significantly greater than for the randomized models, for craters classified as either late-pre-Imbrian (Nectarian), middle pre-Imbrian, or early pre-Imbrian, as well as for a number of larger age-classes. The lunar families tend to center in specific areas of the moon; these lie in highlands rather than maria and are different for families of Nectarian craters than for pre-Nectarian. The origin of the arcuate crater groupings is not understood.

SU-E-T-230: Creating a Large Number of Focused Beams with Variable Patient Head Tilt to Improve Dose Fall-Off for Brain Radiosurgery

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

Chiu, J; Ma, L

2015-06-15

Purpose: To develop a treatment delivery and planning strategy by increasing the number of beams to minimize dose to brain tissue surrounding a target, while maximizing dose coverage to the target. Methods: We analyzed 14 different treatment plans via Leksell PFX and 4C. For standardization, single tumor cases were chosen. Original treatment plans were compared with two optimized plans. The number of beams was increased in treatment plans by varying tilt angles of the patient head, while maintaining original isocenter and the beam positions in the x-, y- and z-axes, collimator size, and beam blocking. PFX optimized plans increased beammore » numbers with three pre-set tilt angles, 70, 90, 110, and 4C optimized plans increased beam numbers with tilt angles increasing arbitrarily from range of 30 to 150 degrees. Optimized treatment plans were compared dosimetrically with original treatment plans. Results: Comparing total normal tissue isodose volumes between original and optimized plans, the low-level percentage isodose volumes decreased in all plans. Despite the addition of multiple beams up to a factor of 25, beam-on times for 1 tilt angle versus 3 or more tilt angles were comparable (<1 min.). In 64% (9/14) of the studied cases, the volume percentage decrease by >5%, with the highest value reaching 19%. The addition of more tilt angles correlates to a greater decrease in normal brain irradiated volume. Selectivity and coverage for original and optimized plans remained comparable. Conclusion: Adding large number of additional focused beams with variable patient head tilt shows improvement for dose fall-off for brain radiosurgery. The study demonstrates technical feasibility of adding beams to decrease target volume.« less

MMSET is dynamically regulated during cell-cycle progression and promotes normal DNA replication.

PubMed

Evans, Debra L; Zhang, Haoxing; Ham, Hyoungjun; Pei, Huadong; Lee, SeungBaek; Kim, JungJin; Billadeau, Daniel D; Lou, Zhenkun

2016-01-01

The timely and precise duplication of cellular DNA is essential for maintaining genome integrity and is thus tightly-regulated. During mitosis and G1, the Origin Recognition Complex (ORC) binds to future replication origins, coordinating with multiple factors to load the minichromosome maintenance (MCM) complex onto future replication origins as part of the pre-replication complex (pre-RC). The pre-RC machinery, in turn, remains inactive until the subsequent S phase when it is required for replication fork formation, thereby initiating DNA replication. Multiple myeloma SET domain-containing protein (MMSET, a.k.a. WHSC1, NSD2) is a histone methyltransferase that is frequently overexpressed in aggressive cancers and is essential for normal human development. Several studies have suggested a role for MMSET in cell-cycle regulation; however, whether MMSET is itself regulated during cell-cycle progression has not been examined. In this study, we report that MMSET is degraded during S phase in a cullin-ring ligase 4-Cdt2 (CRL4(Cdt2)) and proteasome-dependent manner. Notably, we also report defects in DNA replication and a decreased association of pre-RC factors with chromatin in MMSET-depleted cells. Taken together, our results suggest a dynamic regulation of MMSET levels throughout the cell cycle, and further characterize the role of MMSET in DNA replication and cell-cycle progression.

Acoustic transducer

DOEpatents

Drumheller, Douglas S.

2000-01-01

An active acoustic transducer tool for use down-hole applications. The tool includes a single cylindrical mandrel including a shoulder defining the boundary of a narrowed portion over which is placed a sandwich-style piezoelectric tranducer assembly. The piezoelectric transducer assembly is prestressed by being placed in a thermal interference fit between the shoulder of the mandrel and the base of an anvil which is likewise positioned over the narrower portion of the mandrel. In the preferred embodiment, assembly of the tool is accomplished using a hydraulic jack to stretch the mandrel prior to emplacement of the cylindrical sandwich-style piezoelectric transducer assembly and anvil. After those elements are positioned and secured, the stretched mandrel is allowed to return substantially to its original (pre-stretch) dimensions with the result that the piezoelectric transducer elements are compressed between the anvil and the shoulder of the mandrel.

Nitro stretch probing of a single molecular layer to monitor shock compression with picosecond time resolution

NASA Astrophysics Data System (ADS)

Berg, Christopher; Lagutchev, Alexei; Fu, Yuanxi; Dlott, Dana

2012-03-01

Ultrafast shock compression vibrational spectroscopy experiments with molecular monolayers provide atomic-scale time and space resolution, which enables critical testing of reactive molecular simulations. Since the origination of this project, we have greatly improved the ability to detect shocked monolayers by nonlinear coherent vibrational spectroscopy with nonresonant suppression. In this study, we show new results on a nitroaromatic monolayer, where the nitro symmetric stretch is probed. A small frequency blue-shift under shock conditions compared to measurements with static high pressure shows the shock is ~1 GPa. The ability to flash-preheat the monolayer by several hundred K is demonstrated. In order to observe shock monolayer chemistry in real time, along with pre-heating, the shock pressure needs to be increased and methods to do so are described.

28 CFR 345.35 - Assignments to FPI.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., color, religion, ethnic origin, age, or disability. (b) The SOI ordinarily makes assignments based on... course in pre-industrial training or on-the-job training (as available) before promotion to pay grade four. (2) An inmate who has not successfully completed pre-industrial or on-the-job training remains at...

41 CFR 105-56.004 - Pre-offset notice.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Pre-offset notice. 105-56.004 Section 105-56.004 Public Contracts and Property Management Federal Property Management... from disposable pay informing him or her of— (a) The nature, origin and amount of the indebtedness...

75 FR 64654 - Extension of Import Restrictions Imposed on Certain Categories of Archaeological Material From...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-20

... Categories of Archaeological Material From the Pre-Hispanic Cultures of the Republic of Nicaragua AGENCY... cultures of the Republic of Nicaragua. The restrictions, which were originally imposed by Treasury Decision... material representing Pre-Hispanic cultures of Nicaragua to which the restrictions apply. DATES: Effective...

15 CFR 760.3 - Exceptions to prohibitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... origin at the time of their entry into the boycotting country by (a) uniqueness of design or appearance... by a United States person does not come within this exception. (6) The provision of so-called “pre-selection” or “pre-award” services, such as providing lists of qualified suppliers, subcontractors, or...

15 CFR 760.3 - Exceptions to prohibitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... origin at the time of their entry into the boycotting country by (a) uniqueness of design or appearance... by a United States person does not come within this exception. (6) The provision of so-called “pre-selection” or “pre-award” services, such as providing lists of qualified suppliers, subcontractors, or...

15 CFR 760.3 - Exceptions to prohibitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... origin at the time of their entry into the boycotting country by (a) uniqueness of design or appearance... by a United States person does not come within this exception. (6) The provision of so-called “pre-selection” or “pre-award” services, such as providing lists of qualified suppliers, subcontractors, or...

125. Pre1911. Crew on main deck, starboard side at main ...

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

125. Pre-1911. Crew on main deck, starboard side at main hatch, looking aft. Note dark object in center of photo that may be original main deck capstan. Fred Heick collection. (K9.9571) - Ship BALCLUTHA, 2905 Hyde Street Pier, San Francisco, San Francisco County, CA

The value of integrating pre-clinical data to predict nausea and vomiting risk in humans as illustrated by AZD3514, a novel androgen receptor modulator.

PubMed

Grant, Claire; Ewart, Lorna; Muthas, Daniel; Deavall, Damian; Smith, Simon A; Clack, Glen; Newham, Pete

2016-04-01

Nausea and vomiting are components of a complex mechanism that signals food avoidance and protection of the body against the absorption of ingested toxins. This response can also be triggered by pharmaceuticals. Predicting clinical nausea and vomiting liability for pharmaceutical agents based on pre-clinical data can be problematic as no single animal model is a universal predictor. Moreover, efforts to improve models are hampered by the lack of translational animal and human data in the public domain. AZD3514 is a novel, orally-administered compound that inhibits androgen receptor signaling and down-regulates androgen receptor expression. Here we have explored the utility of integrating data from several pre-clinical models to predict nausea and vomiting in the clinic. Single and repeat doses of AZD3514 resulted in emesis, salivation and gastrointestinal disturbances in the dog, and inhibited gastric emptying in rats after a single dose. AZD3514, at clinically relevant exposures, induced dose-responsive "pica" behaviour in rats after single and multiple daily doses, and induced retching and vomiting behaviour in ferrets after a single dose. We compare these data with the clinical manifestation of nausea and vomiting encountered in patients with castration-resistant prostate cancer receiving AZD3514. Our data reveal a striking relationship between the pre-clinical observations described and the experience of nausea and vomiting in the clinic. In conclusion, the emetic nature of AZD3514 was predicted across a range of pre-clinical models, and the approach presented provides a valuable framework for predicition of clinical nausea and vomiting. Copyright © 2016 Elsevier Inc. All rights reserved.

Single transcriptional and translational preQ1 riboswitches adopt similar pre-folded ensembles that follow distinct folding pathways into the same ligand-bound structure

PubMed Central

Suddala, Krishna C.; Rinaldi, Arlie J.; Feng, Jun; Mustoe, Anthony M.; Eichhorn, Catherine D.; Liberman, Joseph A.; Wedekind, Joseph E.; Al-Hashimi, Hashim M.; Brooks, Charles L.; Walter, Nils G.

2013-01-01

Riboswitches are structural elements in the 5′ untranslated regions of many bacterial messenger RNAs that regulate gene expression in response to changing metabolite concentrations by inhibition of either transcription or translation initiation. The preQ1 (7-aminomethyl-7-deazaguanine) riboswitch family comprises some of the smallest metabolite sensing RNAs found in nature. Once ligand-bound, the transcriptional Bacillus subtilis and translational Thermoanaerobacter tengcongensis preQ1 riboswitch aptamers are structurally similar RNA pseudoknots; yet, prior structural studies have characterized their ligand-free conformations as largely unfolded and folded, respectively. In contrast, through single molecule observation, we now show that, at near-physiological Mg2+ concentration and pH, both ligand-free aptamers adopt similar pre-folded state ensembles that differ in their ligand-mediated folding. Structure-based Gō-model simulations of the two aptamers suggest that the ligand binds late (Bacillus subtilis) and early (Thermoanaerobacter tengcongensis) relative to pseudoknot folding, leading to the proposal that the principal distinction between the two riboswitches lies in their relative tendencies to fold via mechanisms of conformational selection and induced fit, respectively. These mechanistic insights are put to the test by rationally designing a single nucleotide swap distal from the ligand binding pocket that we find to predictably control the aptamers′ pre-folded states and their ligand binding affinities. PMID:24003028

Influence of different pre-etching times on fatigue strength of self-etch adhesives to dentin.

PubMed

Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Suzuki, Takayuki; Scheidel, Donal D; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

2016-04-01

The purpose of this study was to use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the influence on dentin bonding of phosphoric acid pre-etching times before the application of self-etch adhesives. Two single-step self-etch universal adhesives [Prime & Bond Elect (EL) and Scotchbond Universal (SU)], a conventional single-step self-etch adhesive [G-aenial Bond (GB)], and a two-step self-etch adhesive [OptiBond XTR (OX)] were used. The SBS and SFS values were obtained with phosphoric acid pre-etching times of 3, 10, or 15 s before application of the adhesives, and for a control without pre-etching. For groups with 3 s of pre-etching, SU and EL showed higher SBS values than control groups. No significant difference was observed for GB among the 3 s, 10 s, and control groups, but the 15 s pre-etching group showed significantly lower SBS and SFS values than the control group. No significant difference was found for OX among the pre-etching groups. Reducing phosphoric acid pre-etching time can minimize the adverse effect on dentin bonding durability for the conventional self-etch adhesives. Furthermore, a short phosphoric acid pre-etching time enhances the dentin bonding performance of universal adhesives. © 2016 Eur J Oral Sci.

Methylxanthines do not affect rhythmogenic preBötC inspiratory network activity but impair bursting of preBötC-driven motoneurons.

PubMed

Panaitescu, B; Kuribayashi, J; Ruangkittisakul, A; Leung, V; Iizuka, M; Ballanyi, K

2013-01-01

Clinical stimulation of preterm infant breathing with methylxanthines like caffeine and theophylline can evoke seizures. It is unknown whether underlying neuronal hyperexcitability involves the rhythmogenic inspiratory active pre-Bötzinger complex (preBötC) in the brainstem or preBötC-driven motor networks. Inspiratory-related preBötC interneuronal plus spinal (cervical/phrenic) or cranial hypoglossal (XII) motoneuronal bursting was studied in newborn rat en bloc brainstem-spinal cords and brainstem slices, respectively. Non-respiratory bursting perturbed inspiratory cervical nerve activity in en bloc models at >0.25mM theophylline or caffeine. Rhythm in the exposed preBötC of transected en bloc preparations was less perturbed by 10mM theophylline than cervical root bursting which was more affected than phrenic nerve activity. In the preBötC of slices, even 10mM methylxanthine did not evoke seizure-like bursting whereas >1mM masked XII rhythm via large amplitude 1-10Hz oscillations. Blocking A-type γ-aminobutyric (GABAA) receptors evoked seizure-like cervical activity whereas in slices neither XII nor preBötC rhythm was disrupted. Methylxanthines (2.5-10mM), but not blockade of adenosine receptors, phosphodiesterase-4 or the sarcoplasmatic/endoplasmatic reticulum ATPase countered inspiratory depression by muscimol-evoked GABAA receptor activation that was associated with a hyperpolarization and input resistance decrease silencing preBötC neurons in slices. The latter blockers did neither affect preBötC or cranial/spinal motor network bursting nor evoke seizure-like activity or mask corresponding methylxanthine-evoked discharges. Our findings show that methylxanthine-evoked hyperexcitability originates from motor networks, leaving preBötC activity largely unaffected, and suggest that GABAA receptors contribute to methylxanthine-evoked seizure-like perturbation of spinal motoneurons whereas non-respiratory XII motoneuron oscillations are of different origin. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists

PubMed Central

Sengupta, Sanghamitra; Zhivotovsky, Lev A.; King, Roy; Mehdi, S. Q.; Edmonds, Christopher A.; Chow, Cheryl-Emiliane T.; Lin, Alice A.; Mitra, Mitashree; Sil, Samir K.; Ramesh, A.; Usha Rani, M. V.; Thakur, Chitra M.; Cavalli-Sforza, L. Luca; Majumder, Partha P.; Underhill, Peter A.

2006-01-01

Although considerable cultural impact on social hierarchy and language in South Asia is attributable to the arrival of nomadic Central Asian pastoralists, genetic data (mitochondrial and Y chromosomal) have yielded dramatically conflicting inferences on the genetic origins of tribes and castes of South Asia. We sought to resolve this conflict, using high-resolution data on 69 informative Y-chromosome binary markers and 10 microsatellite markers from a large set of geographically, socially, and linguistically representative ethnic groups of South Asia. We found that the influence of Central Asia on the pre-existing gene pool was minor. The ages of accumulated microsatellite variation in the majority of Indian haplogroups exceed 10,000–15,000 years, which attests to the antiquity of regional differentiation. Therefore, our data do not support models that invoke a pronounced recent genetic input from Central Asia to explain the observed genetic variation in South Asia. R1a1 and R2 haplogroups indicate demographic complexity that is inconsistent with a recent single history. Associated microsatellite analyses of the high-frequency R1a1 haplogroup chromosomes indicate independent recent histories of the Indus Valley and the peninsular Indian region. Our data are also more consistent with a peninsular origin of Dravidian speakers than a source with proximity to the Indus and with significant genetic input resulting from demic diffusion associated with agriculture. Our results underscore the importance of marker ascertainment for distinguishing phylogenetic terminal branches from basal nodes when attributing ancestral composition and temporality to either indigenous or exogenous sources. Our reappraisal indicates that pre-Holocene and Holocene-era—not Indo-European—expansions have shaped the distinctive South Asian Y-chromosome landscape. PMID:16400607

Meteorological, atmospheric and climatic perturbations during major dust storms over Indo-Gangetic Basin

NASA Astrophysics Data System (ADS)

Kumar, Sarvan; Kumar, Sanjay; Kaskaoutis, D. G.; Singh, Ramesh P.; Singh, Rajeev K.; Mishra, Amit K.; Srivastava, Manoj K.; Singh, Abhay K.

2015-06-01

During the pre-monsoon season (April-June), the Indo-Gangetic Basin (IGB) suffers from frequent and intense dust storms originated from the arid and desert regions of southwest Asia (Iran, Afghanistan), Arabia and Thar desert blanketing IGB and Himalayan foothills. The present study examines the columnar and vertical aerosol characteristics and estimates the shortwave (0.25-4.0 μm) aerosol radiative forcing (ARF) and atmospheric heating rates over Kanpur, central IGB, during three intense dust-storm events in the pre-monsoon season of 2010. MODIS images, meteorological and AERONET observations clearly show that all the dust storms either originated from the Thar desert or transported over, under favorable meteorological conditions (low pressure and strong surface winds) affecting nearly the whole IGB and modifying the aerosol loading and characteristics (Ångström exponent, single scattering albedo, size distribution and refractive index). CALIPSO observations reveal the presence of high-altitude (up to 3-5 km) dust plumes that strongly modify the vertical aerosol profile and are transported over Himalayan foothills with serious climate implications (atmospheric warming, enhanced melting of glaciers). Shortwave ARF calculations over Kanpur using SBDART model show large negative forcing values at the surface (-93.27, -101.60 and -66.71 W m-2) during the intense dusty days, associated with planetary (top of atmosphere) cooling (-18.16, -40.95, -29.58 W m-2) and significant atmospheric heating (75.11, 60.65, 37.13 W m-2), which is translated to average heating rates of 1.57, 1.41 and 0.78 K day-1, respectively in the lower atmosphere (below ∼3.5 km). The ARF estimates are in satisfactory agreement with the AERONET ARF retrievals over Kanpur.

Constraining the Origin and Heating Mechanism of Dust in Type IIn Supernovae

NASA Astrophysics Data System (ADS)

Fox, Ori; Skrutskie, Michael; Filippenko, Alex

2012-12-01

More than any other supernova subclass, Type IIn supernovae tend to exhibit late-time (>1 year) infrared emission from warm dust. Identifying the origin and heating mechanism of the dust provides an important probe of the supernova explosion, circumstellar environment, and progenitor system. Yet mid-infrared observations, which span the peak of the thermal emission, are rare. Three years ago, we executed a warm Spitzer survey (P60122) that uncovered a unique sample of ten supernovae with unreported late-time infrared excesses, in some cases more than 5 years post-explosion. The data from this single epoch are most consistent with a pre-existing dust shell that is continuously heated by visible and/or X-ray emission generated by ongoing shock interaction. Furthermore, the lack of any detections beyond ~2000 days suggests the dust is destroyed once the forward shock overruns the pre-existing shell. The actual shell sizes remain unknown, however, since the derived blackbody radii offer only lower limits. Last year, we obtained second epoch observations of these ten re-discovered SNe IIn (plus the well-studied Type IIn SN 2010jl). The project aimed for non-detections to constrain the light-curve ``turn-off'' times and, thereby, the shell sizes and progenitor mass-loss models. Only two SNe (2005gn and 2008J), however, went undetected. The other nine SNe remain bright at mid-IR wavelengths, which means the dust shell radii are larger than expected. Here we propose continued monitoring of these nine SNe IIn to constrain the size of the circumstellar dust shell and characterize the supernova progenitor system. We can obtain all the necessary data in only 6.1 hours of observation.

Revision Roux-en-Y Gastric Bypass to Biliopancreatic Long-Limb Gastric Bypass for Inadequate Weight Response: Case Series and Analysis.

PubMed

Buchwald, Henry; Oien, Danette M

2017-09-01

The long-limb Roux-en-Y gastric bypass (LLRYGB) was introduced in 1987 as a salvage operation for inadequate weight loss after a standard Roux-en-Y gastric bypass (RYGB). We report on 53 consecutive patients (44 females) with conversion of a failed RYGB to a LLRYGB performed by a single surgeon between 2002 and 2014. No patient had an ascertainable anatomic abnormality to explain his/her weight regain. LLRYGB revision consisted of a 75-cm to 100-cm alimentary Roux limb and a 75-cm to 100-cm common channel; after 2011, in suitable patients, the Roux limb was lengthened to greater than 250 cm. Average values for weight (lbs) were as follows: pre-original RYGB = 329; lowest measured after RYGB = 196; at time of LLRYGB = 285; and at 1, 2, 3, 4, >5 years post LLRYGB = 225, 207, 199, 197, 195, for a sustained weight loss >90 lbs. Average values for BMI (kg/m 2 ) were as follows: pre-original RYGB = 54.3; lowest measured after RYGB = 32.3; at time of LLRYGB = 47.2; and at 1, 2, 3, 4, >5 years post LLRYGB = 37.1, 34.4, 33.0, 32.8, 31.4, for a sustained BMI reduction >16.5 kg/m 2 . Zero operative mortality; 3 (5.7%) late deaths; 7 (13.2%) 30-day complications; 33 (62.3%) long-term complications with 23 (43.4%) needing TPN; and 14 (26.4%) requiring operative revision. A salvage LLRYGB procedure can be performed safely and is weight successful, but fraught with long-term nutritional problems and a high necessity for revision. A Roux segment over 250 cm may improve outcomes.

Using Google Earth To Interpret The Southern Taiwan Hsiaolin Village Catastrophe

NASA Astrophysics Data System (ADS)

Lin, Y. H.; Huang, C. M.; Keck, J.; Wei, L. W.; Pan, K. L.

2012-04-01

The August, 2009 Typhoon Morakot resulted in accumulated rainfalls exceeding 2000 mm and the triggering of a massive debris flow that buried Hsiaolin village. Hundreds of people were killed and both domestic and international natural disaster prevention agencies took note of this large scale disaster that was not prevented. Interpretation of Google Earth satellite images reveals that the Hsiaolin debris flow originated in a single location and then split into two parts. The northern debris flow, the smaller of the two parts, flowed within a ravine. The southern part of the debris flow, much larger than the northern part, was responsible for the burial of Hsiaolin village. The movement of the debris flow can be divided into three processes. First a slope failure and subsequent debris flow occurred within a curved ravine. Second, the debris flow eroded the bank of the ravine laterally, causing translational failure of the ravine walls. A massive debris flow, made up of a combination of materials from both the original debris flow and the ravine walls, jammed within the ravine. Finally, as a result of the jam, the debris flow was redirected towards Hsiaolin village. Overlaying locations of the post-Hsiaolin debris flow landforms on top of pre-failure satellite images reveals that characteristics of the post failure landforms match perfectly with characteristics observed in the pre-failure satellite images. This finding supports the thought that large scale geologic disasters are reoccurring. This finding also suggests that areas near villages can use simple satellite image analysis to rapidly identify ancient landslides and that such information may help early evacuation planning. With such planning, property and life losses due to natural disasters can be reduced. Key word: Hsiaolin Village, Debris Flow, Remote Sensing, Image Interpretation, Cause of Disaster, Disaster Recovery, Deep-Seated Landslide, Ancient Debris Flow

Development and validation of a Hindi language health-related quality of life questionnaire for melasma in Indian patients.

PubMed

Sarkar, Rashmi; Garg, Shilpa; Dominguez, Arturo; Balkrishnan, Rajesh; Jain, R K; Pandya, Amit G

2016-01-01

Melasma, which is fairly common in Indians, causes significant emotional and psychological impact. A Hindi instrument would be useful to assess the impact of melasma on the quality of life in Indian patients. To create a semantic equivalent of the original MELASQOL questionnaire in Hindi and validate it. A Hindi adaptation of the original MELASQOL (Hi-MELASQOL) was prepared using previously established guidelines. After pre-testing, the Hi-MELASQOL questionnaire was administered to 100 women with melasma visiting the out-patient registration counter of Safdarjung Hospital, Delhi. These women were also administered a Hindi equivalent of the Health Related Quality of Life (HRQOL) questionnaire. Melasma area severity index (MASI) of all the participants was calculated. The mean MASI score was 20.0 ± 7.5 and Hi-MELASQOL score was 37.19 ± 18.15; both were highly, positively and significantly correlated. Reliability analysis showed satisfactory results. Physical health, emotional well-being and social life were the most adversely affected life domains. It was a single-center study and the number of patients studied could have been larger. Hi-MELASQOL is a reliable and validated tool to measure the quality of life in Indians with melasma.

Influence of Pre-etching Times on Fatigue Strength of Self-etch Adhesives to Enamel.

PubMed

Takamizawa, Toshiki; Barkmeier, Wayne W; Tsujimoto, Akimasa; Endo, Hajime; Tsuchiya, Kenji; Erickson, Robert L; Latta, Mark A; Miyazaki, Masashi

To use shear bond strength (SBS) and shear fatigue strength (SFS) testing to determine the influence of phosphoric acid pre-etching times prior to application of self-etch adhesives on enamel bonding. Two single-step self-etch universal adhesives (Prime&Bond Elect and Scotchbond Universal), a conventional single-step self-etch adhesive (G-ӕnial Bond), and a conventional two-step self-etch adhesive (OptiBond XTR) were used. The SBS and SFS were obtained with phosphoric acid pre-etching for 3, 10, or 15 s prior to application of the adhesives, and without pre-etching (0 s) as a control. A staircase method was used to determine the SFS with 10 Hz frequency for 50,000 cycles or until failure occurred. The mean demineralization depth for each treated enamel surface was also measured using a profilometer. For all the adhesives, the groups with pre-etching showed significantly higher SBS and SFS than groups without pre-etching. However, there was no significant difference in SBS and SFS among groups with > 3 s of preetching. In addition, although the groups with pre-etching showed significantly deeper demineralization depths than groups without pre-etching, there was no significant difference in depth among groups with > 3 s of pre-etching. Three seconds of phosphoric acid pre-etching prior to application of self-etch adhesive can enhance enamel bonding effectiveness.

Visual awareness suppression by pre-stimulus brain stimulation; a neural effect.

PubMed

Jacobs, Christianne; Goebel, Rainer; Sack, Alexander T

2012-01-02

Transcranial magnetic stimulation (TMS) has established the functional relevance of early visual cortex (EVC) for visual awareness with great temporal specificity non-invasively in conscious human volunteers. Many studies have found a suppressive effect when TMS was applied over EVC 80-100 ms after the onset of the visual stimulus (post-stimulus TMS time window). Yet, few studies found task performance to also suffer when TMS was applied even before visual stimulus presentation (pre-stimulus TMS time window). This pre-stimulus TMS effect, however, remains controversially debated and its origin had mainly been ascribed to TMS-induced eye-blinking artifacts. Here, we applied chronometric TMS over EVC during the execution of a visual discrimination task, covering an exhaustive range of visual stimulus-locked TMS time windows ranging from -80 pre-stimulus to 300 ms post-stimulus onset. Electrooculographical (EoG) recordings, sham TMS stimulation, and vertex TMS stimulation controlled for different types of non-neural TMS effects. Our findings clearly reveal TMS-induced masking effects for both pre- and post-stimulus time windows, and for both objective visual discrimination performance and subjective visibility. Importantly, all effects proved to be still present after post hoc removal of eye blink trials, suggesting a neural origin for the pre-stimulus TMS suppression effect on visual awareness. We speculate based on our data that TMS exerts its pre-stimulus effect via generation of a neural state which interacts with subsequent visual input. Copyright © 2011 Elsevier Inc. All rights reserved.

Revalidation of game for teaching blood pressure auscultatory measurement: a pilot study.

PubMed

Bellan, Margarete Consorti; Alves, Vanessa Cortez; Neves, Mayza Luzia Dos Santos; Lamas, José Luiz Tatagiba

2017-01-01

To adapt a pre-existing educational game, making it specific to the teaching of blood pressure auscultatory measurement, and to apply this game in a pilot study. The original game cards were altered by the authors and submitted to content validation by six experts in the field. After redesigns, the game was applied to 30 subjects, who answered a questionnaire (pre-test and post-test) on auscultatory measurement. Data were analyzed descriptively and by the paired Student's t-test and paired Wilcoxon test. Throughout the content validation process, 17 of the 28 original cards were modified. Of these 17 cards, 13 obtained 80% agreement, and the rest were modified according to the judges' suggestions. The obtained grades significantly increased between pre- and the post-test. It was concluded that the reformulated game presented satisfactory evidence of content validity. Its use as a teaching-learning method was effective for this sample.

Origin of the pre-tropical storm Debby (2006) African easterly wave-mesoscale convective system

NASA Astrophysics Data System (ADS)

Lin, Yuh-Lang; Liu, Liping; Tang, Guoqing; Spinks, James; Jones, Wilson

2013-05-01

The origins of the pre-Debby (2006) mesoscale convective system (MCS) and African easterly wave (AEW) and their precursors were traced back to the southwest Arabian Peninsula, Asir Mountains (AS), and Ethiopian Highlands (EH) in the vicinity of the ITCZ using satellite imagery, GFS analysis data and ARW model. The sources of the convective cloud clusters and vorticity perturbations were attributed to the cyclonic convergence of northeasterly Shamal wind and the Somali jet, especially when the Mediterranean High shifted toward east and the Indian Ocean high strengthened and its associated Somali jet penetrated farther to the north. The cyclonic vorticity perturbations were strengthened by the vorticity stretching associated with convective cloud clusters in the genesis region—southwest Arabian Peninsula. A conceptual model was proposed to explain the genesis of convective cloud clusters and cyclonic vorticity perturbations preceding the pre-Debby (2006) AEW-MCS system.

12 CFR Appendix A to Subpart B of... - Risk-Based Capital Stress Test

Code of Federal Regulations, 2010 CFR

2010-01-01

... Loan Number Ending Scheduled Balance Group Pre/Post Act Property State Product Type Origination Date... program assets post-1996 Act Swap balances; (iii) Farmer Mac I program assets pre-1996 Act; (iv) Farmer... stress test applies quarterly updates of the weighted average guarantee rates for post-1996 Farmer Mac I...

12 CFR Appendix A to Subpart B of... - Risk-Based Capital Stress Test

Code of Federal Regulations, 2011 CFR

2011-01-01

... Loan Number Ending Scheduled Balance Group Pre/Post Act Property State Product Type Origination Date... program assets post-1996 Act Swap balances; (iii) Farmer Mac I program assets pre-1996 Act; (iv) Farmer... stress test applies quarterly updates of the weighted average guarantee rates for post-1996 Farmer Mac I...

123. Pre1911. View forward from near mizzen hatch, starboard side ...

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

123. Pre-1911. View forward from near mizzen hatch, starboard side showing crew standing on a load of lumber. Note main fife rail, small hatch with cover (possibly original 'lime juice hatch') just aft. Fred Heick Collection. - Ship BALCLUTHA, 2905 Hyde Street Pier, San Francisco, San Francisco County, CA

Biblio-Therapeutic Book Creations by Pre-Service Student Teachers: Helping Elementary School Children Cope

ERIC Educational Resources Information Center

Haeseler, Lisa Ann

2009-01-01

Many elementary school children may cope with difficult life struggles such as disabilities, abuse, loss, and identity issues. This article details original, student generated, biblio-therapeutic book creations and how this genre teaches positive ways for children at-risk to cope with tough life circumstances. Pre-service, elementary college…

75 FR 10411 - Extension of Import Restrictions Imposed on Certain Categories of Archaeological Material From...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-08

... Categories of Archaeological Material From the Pre-Hispanic Cultures of the Republic of El Salvador AGENCIES...-Hispanic cultures of the Republic of El Salvador (El Salvador). The restrictions, which were originally... List of archaeological material representing Pre-Hispanic cultures of El Salvador, and describes the...

Are We Making "PROGRESS"? A Critical Literacies Framework to Engage Pre-Service Teachers for Social Justice

ERIC Educational Resources Information Center

Matteson, Holly C.; Boyd, Ashley S.

2017-01-01

In this article, authors describe an original framework aimed to acquaint pre-service English teachers with concepts related to social justice to facilitate their critical literacies related to eight components: positionality, race, orientation, gender, relationships, environment, social class, and stereotypes (PROGRESS). Authors then illustrate…

My Teaching Partner-Secondary: A Video-Based Coaching Model

ERIC Educational Resources Information Center

Gregory, A.; Ruzek, E.; Hafen, C. A.; Mikami, A. Y.; Allen, J. P.; Pianta, R. C.

2017-01-01

In the My Teaching Partner (MTP) program, coaches engage teachers in 6 to 9 coaching cycles across a school year. Guided by the program's theory, coaches help teachers reflect on the emotional, organizational, and instructional features of classrooms. MTP was originally developed for pre-K and early elementary classrooms (MTP Pre-K), but this…

Late Pleistocene to Holocene lake levels of Lake Warner, Oregon (USA) and their effect on archaeological site distribution patterns

NASA Astrophysics Data System (ADS)

Wriston, T.; Smith, G. M.

2017-12-01

Few chronological controls are available for the rise and fall of small pluvial lake systems in the Northwestern Great Basin. Within Warner Basin this control was necessary for interpretation of known archaeological sites and for predicting where evidence of its earliest inhabitants might be expected. We trenched along relic beach ridges of Lake Warner, surveyed a stratified sample of the area for archaeological sites, and excavated some sites and a nearby rockshelter. These efforts produced new ages that we used to construct a lake level curve for Lake Warner. We found that the lake filled the valley floor between ca. 30,000 cal yr BP and ca. 10,300 cal yr BP. In nearby basins, several oscillations are evident before ca. 21,100 cal yr BP, but a steep rise to the LGM maximum occurred between 21,000 and 20,000 cal yr BP. Lake Warner likely mirrored these changes, dropped to the valley floor ca. 18,340 cal yr BP, and then rose to its maximum highstand when its waters briefly reached 1454 m asl. After this highstand the lake receded to moderately high levels. Following ca. 14,385 cal yr BP, the lake oscillated between moderate to moderately-high levels through the Bolling-Allerod interstadials and into the Younger Dryas stadial. The basin's first occupants arrived along its shore around this time, while the lake still filled the valley floor. These earliest people carried either Western Stemmed or Clovis projectile points, both of which are found along the lake margin. The lake receded into the valley floor ca. 10,300 cal yr BP and dune development began, ringing wetlands and small lakes that persisted in the footprint of the once large lake. By the time Mazama tephra fell 7,600 cal yr BP it blanketed pre-existing dunes and marsh peats. Our Lake Warner lake level curve facilitates interdisciplinary testing and refinement of it and similar curves throughout the region while helping us understand the history of lake and the people who lived along its shores.

The Arrival of Homo sapiens into the Southern Cone at 14,000 Years Ago

PubMed Central

Politis, Gustavo G.; Gutiérrez, María A.; Blasi, Adriana

2016-01-01

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America. PMID:27683248

Comparability of the effect of storage time and temperature on serum anti-Müllerian hormone measurement between original and modified enzyme-linked immunosorbent assay.

PubMed

Yue, Chao-Yan; Ying, Chun-Mei

2017-01-01

To explore the effect of modified enzyme-linked immunosorbent assay on the AMH results is increased or decreased, and to investigate the effect of storage time and temperature on AMH measurements with and without sample premixing assay buffer using the Kangrun ELISA method. Serum AMH concentration were measured by ELISA, consistency between two kits, and comparability between original and the modified assay under different stored conditions were analyzed by Passing-Bablok regression analysis and Bland-Altman bias evaluation. There was a strong consistency between AMH concentrations measured in Kangrun ELISA and Ansh Labs ultra-sensitive AMH ELISA. Pre-mixing serum specimens with assay buffer gave consistent results compared with original assay. Modified protocol can reduce the amplitude of increase affected by sample aged and give the most consistent results regardless of storage conditions. Pre-mixing protocol did not influence the results of fresh serum or frozen serum incubation <3days at 4°C and -80°C, but when specimens detected after collection and stored in other storage conditions, should be pre-mixed with assay buffer to insure its accuracy. Copyright © 2016 Elsevier B.V. All rights reserved.

Boston University Pre-Majors Program (BU Pre-Map): Promoting Diversity through First-Year Undergraduate Research

NASA Astrophysics Data System (ADS)

West, Andrew A.

2014-06-01

One of largest points of attrition for underrepresented minorities in STEM fields is the transition from high school to college. A report from Building Engineering and Science Talent (BEST) demonstrates that underrepresented minorities begin college interested in STEM fields at rates equal to (if nor slightly above) their representation in both college and the population (25%). However, by the time they graduate, underrepresented minorities make up only 15% of STEM majors and only 9% of the STEM advanced degrees. Most of the attrition occurs during the first year of college, when large classes, a lack of mentors and challenging courses lead many students (from all backgrounds) to consider other majors.In 2011 I started the Boston University Pre-Majors Program (or BU Pre-MaP), which is modeled after the University of Washington Pre-Majors in Astronomy Program (UW Pre-MAP), a program for recruiting, mentoring and training underrepresented, first-year introductory astronomy students (and of which I was an architect). As a significant part of the Pre-MAP (or Pre-MaP) model, first-year students are engaged in a research project with a faculty or grad-student mentor and learn many of the skills needed to be successful in science.The BU Pre-MaP uses weekly seminars to introduce students to BU and the college environment, discuss ways to be successful in and out of the classroom, highlights the importance of peer mentoring and cohort building and serves as a mechanism to introduce first-year students to research skills. In teams of two, the Pre-MaP students select (with assistance) a research mentor and work with him/her on a original research project.In addition, Pre-MaP students attend several field trips including (but not limited to) viewing original science documents at the Boston Public Library (including a first edition Copernicus) and an observing run at Lowell Observatory in Arizona.

Boston University Pre-Majors Program (BU Pre-Map): Promoting Diversity through First-Year Undergraduate Research

NASA Astrophysics Data System (ADS)

West, Andrew A.

2015-01-01

One of largest points of attrition for underrepresented minorities in STEM fields is the transition from high school to college. A report from Building Engineering and Science Talent (BEST) demonstrates that underrepresented minorities begin college interested in STEM fields at rates equal to (if nor slightly above) their representation in both college and the population (25%). However, by the time they graduate, underrepresented minorities make up only 15% of STEM majors and only 9% of the STEM advanced degrees. Most of the attrition occurs during the first year of college, when large classes, a lack of mentors and challenging courses lead many students (from all backgrounds) to consider other majors.In 2012 I started the Boston University Pre-Majors Program (or BU Pre-MaP), which is modeled after the University of Washington Pre-Majors in Astronomy Program (UW Pre-MAP), a program for recruiting, mentoring and training underrepresented, first-year introductory astronomy students (and of which I was an architect). As a significant part of the Pre-MAP (or Pre-MaP) model, first-year students are engaged in a research project with a faculty or grad-student mentor and learn many of the skills needed to be successful in science.The BU Pre-MaP uses weekly seminars to introduce students to BU and the college environment, discuss ways to be successful in and out of the classroom, highlights the importance of peer mentoring and cohort building and serves as a mechanism to introduce first-year students to research skills. In teams of two, the Pre-MaP students select (with assistance) a research mentor and work with him/her on a original research project.In addition, Pre-MaP students attend several field trips including (but not limited to) viewing original science documents at the Boston Public Library (including a first edition Copernicus) and an observing run at Lowell Observatory in Arizona.

Behavioral and neural bases of extinction learning in Hermissenda

PubMed Central

Cavallo, Joel S.; Hamilton, Brittany N.; Farley, Joseph

2014-01-01

Extinction of classical conditioning is thought to produce new learning that masks or interferes with the original memory. However, research in the nudibranch Hermissenda crassicornis (H.c.) has challenged this view, and instead suggested that extinction erased the original associative memory. We have re-examined extinction in H.c. to test whether extinguished associative memories can be detected on the behavioral and cellular levels, and to characterize the temporal variables involved. Associative conditioning using pairings of light (CS) and rotation (US) produced characteristic suppression of H.c. phototactic behavior. A single session of extinction training (repeated light-alone presentations) reversed suppressed behavior back to pre-training levels when administered 15 min after associative conditioning. This effect was abolished if extinction was delayed by 23 h, and yet was recovered using extended extinction training (three consecutive daily extinction sessions). Extinguished phototactic suppression did not spontaneously recover at any retention interval (RI) tested (2-, 24-, 48-, 72-h), or after additional US presentations (no observed reinstatement). Extinction training (single session, 15 min interval) also reversed the pairing-produced increases in light-evoked spike frequencies of Type B photoreceptors, an identified site of associative memory storage that is causally related to phototactic suppression. These results suggest that the behavioral effects of extinction training are not due to temporary suppression of associative memories, but instead represent a reversal of the underlying cellular changes necessary for the expression of learning. In the companion article, we further elucidate mechanisms responsible for extinction-produced reversal of memory-related neural plasticity in Type B photoreceptors. PMID:25191236

Magnetic Flux Cancellation as the Origin of Solar Quiet-region Pre-jet Minifilaments

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

Panesar, Navdeep K.; Sterling, Alphonse C.; Moore, Ronald L., E-mail: navdeep.k.panesar@nasa.gov

We investigate the origin of 10 solar quiet-region pre-jet minifilaments , using EUV images from the Solar Dynamics Observatory ( SDO )/Atmospheric Imaging Assembly (AIA) and magnetograms from the SDO Helioseismic and Magnetic Imager (HMI). We recently found that quiet-region coronal jets are driven by minifilament eruptions, where those eruptions result from flux cancellation at the magnetic neutral line under the minifilament. Here, we study the longer-term origin of the pre-jet minifilaments themselves. We find that they result from flux cancellation between minority-polarity and majority-polarity flux patches. In each of 10 pre-jet regions, we find that opposite-polarity patches of magneticmore » flux converge and cancel, with a flux reduction of 10%–40% from before to after the minifilament appears. For our 10 events, the minifilaments exist for periods ranging from 1.5 hr to 2 days before erupting to make a jet. Apparently, the flux cancellation builds a highly sheared field that runs above and traces the neutral line, and the cool transition region plasma minifilament forms in this field and is suspended in it. We infer that the convergence of the opposite-polarity patches results in reconnection in the low corona that builds a magnetic arcade enveloping the minifilament in its core, and that the continuing flux cancellation at the neutral line finally destabilizes the minifilament field so that it erupts and drives the production of a coronal jet. Thus, our observations strongly support that quiet-region magnetic flux cancellation results in both the formation of the pre-jet minifilament and its jet-driving eruption.« less

Alternative Fuels Data Center: Plug-In Electric Vehicle Deployment Policy

Science.gov Websites

addendum to a pre-existing zoning ordinance to specify permissible use of EVSE in single- and multi-family -ready requirements may include EVSE installation, pre-wiring, or space reservation. California building charging infrastructure. Examples include the scope of EVSE pre-wiring or installation from a

Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification

PubMed Central

Brewer, Bonita J.; Payen, Celia; Di Rienzi, Sara C.; Higgins, Megan M.; Ong, Giang; Dunham, Maitreya J.; Raghuraman, M. K.

2015-01-01

DNA replication errors are a major driver of evolution—from single nucleotide polymorphisms to large-scale copy number variations (CNVs). Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model—Origin-Dependent Inverted-Repeat Amplification (ODIRA)—proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error—the ligation of leading and lagging nascent strands to create “closed” forks—can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent—a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins of interstitial, inverted CNVs pivotal in human health and evolution. PMID:26700858

Origin-Dependent Inverted-Repeat Amplification: Tests of a Model for Inverted DNA Amplification.

PubMed

Brewer, Bonita J; Payen, Celia; Di Rienzi, Sara C; Higgins, Megan M; Ong, Giang; Dunham, Maitreya J; Raghuraman, M K

2015-12-01

DNA replication errors are a major driver of evolution--from single nucleotide polymorphisms to large-scale copy number variations (CNVs). Here we test a specific replication-based model to explain the generation of interstitial, inverted triplications. While no genetic information is lost, the novel inversion junctions and increased copy number of the included sequences create the potential for adaptive phenotypes. The model--Origin-Dependent Inverted-Repeat Amplification (ODIRA)-proposes that a replication error at pre-existing short, interrupted, inverted repeats in genomic sequences generates an extrachromosomal, inverted dimeric, autonomously replicating intermediate; subsequent genomic integration of the dimer yields this class of CNV without loss of distal chromosomal sequences. We used a combination of in vitro and in vivo approaches to test the feasibility of the proposed replication error and its downstream consequences on chromosome structure in the yeast Saccharomyces cerevisiae. We show that the proposed replication error-the ligation of leading and lagging nascent strands to create "closed" forks-can occur in vitro at short, interrupted inverted repeats. The removal of molecules with two closed forks results in a hairpin-capped linear duplex that we show replicates in vivo to create an inverted, dimeric plasmid that subsequently integrates into the genome by homologous recombination, creating an inverted triplication. While other models have been proposed to explain inverted triplications and their derivatives, our model can also explain the generation of human, de novo, inverted amplicons that have a 2:1 mixture of sequences from both homologues of a single parent--a feature readily explained by a plasmid intermediate that arises from one homologue and integrates into the other homologue prior to meiosis. Our tests of key features of ODIRA lend support to this mechanism and suggest further avenues of enquiry to unravel the origins of interstitial, inverted CNVs pivotal in human health and evolution.

Constraining the Origin and Heating Mechanism of Dust in Type IIn Supernovae

NASA Astrophysics Data System (ADS)

Fox, Ori; Skrutskie, Michael; Chevalier, Roger; Moseley, Samuel Harvey

2011-05-01

More than any other supernova subclass, Type IIn supernovae tend to exhibit late-time (>100 days) infrared emission from warm dust. Identifying the origin and heating mechanism of the dust provides an important probe of the supernova explosion, circumstellar environment, and progenitor system. Yet mid-infrared observations, which span the peak of the thermal emission, are rare. Two years ago, we executed a warm Spitzer survey (P60122) of sixty-eight Type IIn events from the past ten years. The survey uncovered nine supernovae with unreported late-time infrared excesses, in some cases more than 5 years post-explosion. From this single epoch of data, and ground-based optical data, we have determined the likely origin of the mid-infrared emission to be pre-existing dust that is continuously heated by optical emission generated by ongoing circumstellar interaction between the forward shock and circumstellar medium. Furthermore, we noticed an emerging trend suggests these supernovae ``turn off'' at ~1000-2000 days post-discovery once the forward shock overruns the dust shell. Now is the ideal time to build upon this work with a second epoch of observations, which will be necessary to constrain our models. If we catch even a single supernova turning off between the first and second epochs of observation, we will be able to both measure the size of the circumstellar dust shell and characterize of the supernova progenitor system. We can obtain all the necessary data in only 9.3 hours of observation. Our team has extensive experience in infrared supernovae observations. We have already published two papers on one Type IIn supernovae (SN 2005ip) and authored two successful proposal for Spitzer observations of this subclass. This is an ideal application for the Spitzer warm mission, as the 3.6 and 4.5 micron bands span the peak of the thermal emission and provide the necessary constraints on the dust temperature, mass, and luminosity.

Pre- and Post-Head Processing for Single- and Double-Scrambled Sentences of a Head-Final Language as Measured by the Eye Tracking Method

ERIC Educational Resources Information Center

Tamaoka, Katsuo; Asano, Michiko; Miyaoka, Yayoi; Yokosawa, Kazuhiko

2014-01-01

Using the eye-tracking method, the present study depicted pre- and post-head processing for simple scrambled sentences of head-final languages. Three versions of simple Japanese active sentences with ditransitive verbs were used: namely, (1) SO[subscript 1]O[subscript 2]V canonical, (2) SO[subscript 2]O[subscript 1]V single-scrambled, and (3)…

Pre-pregnancy body mass index and inter-pregnancy weight change among women of Russian, Somali and Kurdish origin and the general Finnish population.

PubMed

Bastola, Kalpana; Koponen, Päivikki; Härkänen, Tommi; Gissler, Mika; Kinnunen, Tarja I

2017-05-01

We studied the differences in the mean pre-pregnancy body mass index (BMI) and mean inter-pregnancy weight change in women of Russian, Somali and Kurdish origin and women in the general Finnish population. The population-based samples were from the Migrant Health and Wellbeing Study and the Health 2011 Survey conducted in six cities in Finland in 2010-2012. This study included women with at least one birth in Finland. Data on their previous pregnancies in Finland were obtained from the National Medical Birth Register for 318 Russian, 584 Somali and 373 Kurdish origin women and for 243 women in the general Finnish population (reference group). Data on pre-pregnancy weight and height were self-reported in early pregnancy. Linear logistic regression was the main method of analysis. The unadjusted mean pre-pregnancy BMI was higher in Somali (27.0 kg/m 2 , p<0.001) and Kurdish (25.8 kg/m 2 , p<0.001) women, but lower in Russian (22.2 kg/m 2 , p<0.001) women than in the reference group (24.1 kg/m 2 ). The adjusted coefficients for the difference in the mean pre-pregnancy BMI were -1.93 (95% CI -2.77 to -1.09) for Russian, 1.82 (95% CI 0.89-2.75) for Somali and 1.30 (95% CI 0.43-2.17) for Kurdish women compared with the reference group. Among women with at least two births, no statistically significant difference was observed in the mean inter-pregnancy weight change between the migrant groups and the reference group. Somali and Kurdish women had higher mean pre-pregnancy BMIs than women in the general Finnish population and may need special support and health promotion strategies for weight management.

Playing My Heart Out: Original Play as Adventure.

ERIC Educational Resources Information Center

Donaldson, O. Fred

1999-01-01

"Original" play denotes play that is pre-cultural--before conceptualizations and learned responses. Four anecdotes about play with an infant with Down's syndrome, a child with leukemia, a lioness, and a dying woman illustrate the connections between beings and between the ordinary and the sacred during trusting, fearless, playful encounters. (SV)

Tracing the origin of disseminated tumor cells in breast cancer using single-cell sequencing.

PubMed

Demeulemeester, Jonas; Kumar, Parveen; Møller, Elen K; Nord, Silje; Wedge, David C; Peterson, April; Mathiesen, Randi R; Fjelldal, Renathe; Zamani Esteki, Masoud; Theunis, Koen; Fernandez Gallardo, Elia; Grundstad, A Jason; Borgen, Elin; Baumbusch, Lars O; Børresen-Dale, Anne-Lise; White, Kevin P; Kristensen, Vessela N; Van Loo, Peter; Voet, Thierry; Naume, Bjørn

2016-12-09

Single-cell micro-metastases of solid tumors often occur in the bone marrow. These disseminated tumor cells (DTCs) may resist therapy and lay dormant or progress to cause overt bone and visceral metastases. The molecular nature of DTCs remains elusive, as well as when and from where in the tumor they originate. Here, we apply single-cell sequencing to identify and trace the origin of DTCs in breast cancer. We sequence the genomes of 63 single cells isolated from six non-metastatic breast cancer patients. By comparing the cells' DNA copy number aberration (CNA) landscapes with those of the primary tumors and lymph node metastasis, we establish that 53% of the single cells morphologically classified as tumor cells are DTCs disseminating from the observed tumor. The remaining cells represent either non-aberrant "normal" cells or "aberrant cells of unknown origin" that have CNA landscapes discordant from the tumor. Further analyses suggest that the prevalence of aberrant cells of unknown origin is age-dependent and that at least a subset is hematopoietic in origin. Evolutionary reconstruction analysis of bulk tumor and DTC genomes enables ordering of CNA events in molecular pseudo-time and traced the origin of the DTCs to either the main tumor clone, primary tumor subclones, or subclones in an axillary lymph node metastasis. Single-cell sequencing of bone marrow epithelial-like cells, in parallel with intra-tumor genetic heterogeneity profiling from bulk DNA, is a powerful approach to identify and study DTCs, yielding insight into metastatic processes. A heterogeneous population of CNA-positive cells is present in the bone marrow of non-metastatic breast cancer patients, only part of which are derived from the observed tumor lineages.

Important considerations in the use of carbon and hydrogen stable isotopes to determine the origin of hydrocarbons in groundwater – A case study from pre-shale gas Tioga County

EPA Pesticide Factsheets

stable carbon and hydrogen isotopic compositional ranges of methanes (δ13C and δ2H (D)) enable us to distinguish between microbial and thermogenic origin of natural gases. To identify stray gas origins, identify possible gas sources, create baseline, carry out site-specific monitoring, and monitor long-term changes

Comparing Binaural Pre-processing Strategies III

PubMed Central

Warzybok, Anna; Ernst, Stephan M. A.

2015-01-01

A comprehensive evaluation of eight signal pre-processing strategies, including directional microphones, coherence filters, single-channel noise reduction, binaural beamformers, and their combinations, was undertaken with normal-hearing (NH) and hearing-impaired (HI) listeners. Speech reception thresholds (SRTs) were measured in three noise scenarios (multitalker babble, cafeteria noise, and single competing talker). Predictions of three common instrumental measures were compared with the general perceptual benefit caused by the algorithms. The individual SRTs measured without pre-processing and individual benefits were objectively estimated using the binaural speech intelligibility model. Ten listeners with NH and 12 HI listeners participated. The participants varied in age and pure-tone threshold levels. Although HI listeners required a better signal-to-noise ratio to obtain 50% intelligibility than listeners with NH, no differences in SRT benefit from the different algorithms were found between the two groups. With the exception of single-channel noise reduction, all algorithms showed an improvement in SRT of between 2.1 dB (in cafeteria noise) and 4.8 dB (in single competing talker condition). Model predictions with binaural speech intelligibility model explained 83% of the measured variance of the individual SRTs in the no pre-processing condition. Regarding the benefit from the algorithms, the instrumental measures were not able to predict the perceptual data in all tested noise conditions. The comparable benefit observed for both groups suggests a possible application of noise reduction schemes for listeners with different hearing status. Although the model can predict the individual SRTs without pre-processing, further development is necessary to predict the benefits obtained from the algorithms at an individual level. PMID:26721922

Pheromones and Pheromone Receptors Are Required for Proper Sexual Development in the Homothallic Ascomycete Sordaria macrospora

PubMed Central

Mayrhofer, Severine; Weber, Jan M.; Pöggeler, Stefanie

2006-01-01

The homothallic, filamentous ascomycete Sordaria macrospora is self-fertile and produces sexual fruiting bodies (perithecia) without a mating partner. Even so, S. macrospora transcriptionally expresses two pheromone-precursor genes (ppg1 and ppg2) and two pheromone-receptor genes (pre1 and pre2). The proteins encoded by these genes are similar to α-factor-like and a-factor-like pheromones and to G-protein-coupled pheromone receptors of the yeast Saccharomyces cerevisiae. It has been suggested that in S. macrospora, PPG1/PRE2 and PPG2/PRE1 form two cognate pheromone–receptor pairs. To investigate their function, we deleted (Δ) pheromone-precursor genes (Δppg1, Δppg2) and receptor genes (Δpre1, Δpre2) and generated single- as well as double-knockout strains. No effect on vegetative growth, fruiting-body, and ascospore development was seen in the single pheromone-mutant and receptor-mutant strains, respectively. However, double-knockout strains lacking any compatible pheromone-receptor pair (Δpre2/Δppg2, Δpre1/Δppg1) and the double-pheromone mutant (Δppg1/Δppg2) displayed a drastically reduced number of perithecia and sexual spores, whereas deletion of both receptor genes (Δpre1/Δpre2) completely eliminated fruiting-body and ascospore formation. The results suggest that pheromones and pheromone receptors are required for optimal sexual reproduction of the homothallic S. macrospora. PMID:16387884

Pheromones and pheromone receptors are required for proper sexual development in the homothallic ascomycete Sordaria macrospora.

PubMed

Mayrhofer, Severine; Weber, Jan M; Pöggeler, Stefanie

2006-03-01

The homothallic, filamentous ascomycete Sordaria macrospora is self-fertile and produces sexual fruiting bodies (perithecia) without a mating partner. Even so, S. macrospora transcriptionally expresses two pheromone-precursor genes (ppg1 and ppg2) and two pheromone-receptor genes (pre1 and pre2). The proteins encoded by these genes are similar to alpha-factor-like and a-factor-like pheromones and to G-protein-coupled pheromone receptors of the yeast Saccharomyces cerevisiae. It has been suggested that in S. macrospora, PPG1/PRE2 and PPG2/PRE1 form two cognate pheromone-receptor pairs. To investigate their function, we deleted (delta) pheromone-precursor genes (delta ppg1, delta ppg2) and receptor genes (delta pre1, delta pre2) and generated single- as well as double-knockout strains. No effect on vegetative growth, fruiting-body, and ascospore development was seen in the single pheromone-mutant and receptor-mutant strains, respectively. However, double-knockout strains lacking any compatible pheromone-receptor pair (delta pre2/delta ppg2, delta pre1/delta ppg1) and the double-pheromone mutant (delta ppg1/delta ppg2) displayed a drastically reduced number of perithecia and sexual spores, whereas deletion of both receptor genes (delta pre1/delta pre2) completely eliminated fruiting-body and ascospore formation. The results suggest that pheromones and pheromone receptors are required for optimal sexual reproduction of the homothallic S. macrospora.

Potentiometric surfaces, summer 2013 and winter 2015, and select hydrographs for the Southern High Plains aquifer, Cannon Air Force Base, Curry County, New Mexico

USGS Publications Warehouse

Collison, Jake

2016-04-07

Cannon Air Force Base (Cannon AFB) is located in the High Plains physiographic region of east-central New Mexico, about 5 miles west of Clovis, New Mexico. The area surrounding Cannon AFB is primarily used for agriculture, including irrigated cropland and dairies. The Southern High Plains aquifer is the principal source of water for Cannon AFB, for the nearby town of Clovis, and for local agriculture and dairies. The Southern High Plains aquifer in the vicinity of Cannon AFB consists of three subsurface geological formations: the Chinle Formation of Triassic age, the Ogallala Formation of Tertiary age, and the Blackwater Draw Formation of Quaternary age. The Ogallala Formation is the main water-yielding formation of the Southern High Plains aquifer. Groundwater-supplied, center-pivot irrigation dominates pumping from the Southern High Plains aquifer in the area surrounding Cannon AFB, where the irrigation season typically extends from early March through October. The U.S. Geological Survey has been monitoring groundwater levels in the vicinity of Cannon AFB since 1954 and has developed general potentiometric-surface maps that show groundwater flow from northwest to southeast in the study area. While previous potentiometric-surface maps show the general direction of groundwater flow, a denser well network is needed to show details of groundwater flow at a local scale. Groundwater levels were measured in 93 wells during summer 2013 and 100 wells during winter 2015.The summer and winter potentiometric-surface maps display the presence of what is interpreted to be a groundwater trough trending from the northwest to the southeast through the study area. This groundwater trough may be the hydraulic expression of a Tertiary-age paleochannel. Groundwater north of the trough flows in a southerly direction into the trough, and groundwater south of the trough flows in an easterly direction into the trough.During the 18-month period between summer 2013 and winter 2015, changes in groundwater levels ranged from a rise of 10.0 to a decline of 3.8 feet. The regions to the north and south of the groundwater trough contained the majority of the rises in groundwater levels, whereas the regions within the trough contained the majority of the declines in groundwater levels. In contrast, the long-term groundwater-level trend in wells with 20 to 60 years of record is a steady decline in average annual water levels, with declines ranging from 0.41 to 2.81 feet per year. Overall, the northwestern part of the study area exhibits the smallest average annual declines, while the southeastern part of the study area exhibits the largest average annual declines.

12 CFR Appendix A to Subpart B of... - Risk-Based Capital Stress Test

Code of Federal Regulations, 2013 CFR

2013-01-01

... Loan Number Ending Scheduled Balance Group Pre/Post Act Property State Product Type Origination Date... t-test 2 of the differences in the means for the group of defaulted loans and active loans indicated... of pre-1996 loan volume being transferred to post-1996 loan volume. The interest rate risk and credit...

12 CFR Appendix A to Subpart B of... - Risk-Based Capital Stress Test

Code of Federal Regulations, 2012 CFR

2012-01-01

... Loan Number Ending Scheduled Balance Group Pre/Post Act Property State Product Type Origination Date... t-test 2 of the differences in the means for the group of defaulted loans and active loans indicated... of pre-1996 loan volume being transferred to post-1996 loan volume. The interest rate risk and credit...

12 CFR Appendix A to Subpart B of... - Risk-Based Capital Stress Test

Code of Federal Regulations, 2014 CFR

2014-01-01

... Loan Number Ending Scheduled Balance Group Pre/Post Act Property State Product Type Origination Date... t-test 2 of the differences in the means for the group of defaulted loans and active loans indicated... of pre-1996 loan volume being transferred to post-1996 loan volume. The interest rate risk and credit...

Understanding the Alternative Conceptions of Pre-Service Secondary Science Teachers about Tidal Phenomena Based on Toulmin's Argumentation

ERIC Educational Resources Information Center

Oh, Jun-Young

2014-01-01

Constructing explanations and participating in argumentative discourse are seen as essential practices of scientific inquiry. The objective of this study was to explore the elements and origins of pre-service secondary science teachers' alternative conceptions of tidal phenomena based on the elements used in Toulmin's Argument Model through…

76 FR 28499 - 30-Day Notice of Proposed Information Collection: Form DS-6561, Pre-Assignment for Overseas Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-17

... DEPARTMENT OF STATE [Public Notice 7459] 30-Day Notice of Proposed Information Collection: Form DS-6561, Pre-Assignment for Overseas Duty, OMB 1405-XXXX ACTION: Notice of request for public comments.... OMB Control Number: 1405-XXXX. Type of Request: New. Originating Office: Office of Medical Services, M...

78 FR 55069 - Whitewater Green Energy, LLC; Notice of Intent to File License Application, Filing of Pre...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-09

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14383-005] Whitewater Green... Application for an Original License and Commencing Pre-filing Process. b. Project No.: 14383-005. c. Dated Filed: July 8, 2013. d. Submitted By: Whitewater Green Energy, LLC. e. Name of Project: Whitewater Creek...

TPACK for Pre-Service Science and Mathematics Teachers

ERIC Educational Resources Information Center

Kafyulilo, Ayoub C.

2010-01-01

This article is focused on unveiling the concept of TPACK in relation to teaching and learning in science and mathematics as well as the meaning of TPACK for pre-service science and mathematics teachers training. In describing this, different literatures were consulted on the meaning of TPACK, its origin and the way it can be integrated in…

Study of Aerosol Optical Properties Over Two Sites in the Foothills of the Central Himalayas

NASA Astrophysics Data System (ADS)

Rupakheti, D.; Kang, S.; Cong, Z.; Rupakheti, M.; Tripathee, L.; Panday, A. K.; Holben, B.

2018-04-01

Atmospheric aerosol possesses impacts on climate system and ecological environments, human health and agricultural productivity. The environment over Himalayas and Tibetan Plateau region are continuously degraded due to the transport of pollution from the foothills of the Himalayas; mostly the Indo-Gangetic Plain (IGP). Thus, analysis of aerosol optical properties over two sites; Lumbini and Kathmandu (the southern slope of central Himalayas) using AERONET's CIMEL sun photometer were conducted in this study. Aerosol optical depth (AOD at 500 nm), angstrom exponent (α or AE), volume size distribution (VSD), single scattering albedo (SSA) and asymmetry parameter (AP) were studied for 2013-2014 and the average AOD was found to be: 0.64 ± 0.41 (Lumbini) and 0.45 ± 0.30 (Kathmandu). The average AE was found to be: 1.25 ± 0.24 and 1.26 ± 0.18 respectively for two sites. The relation between AOD and AE was used to discriminate the aerosol types over these sites which indicated anthropogenic, mixed and biomass burning origin aerosol constituted the major aerosol types in Lumbini and Kathmandu. A clear bi-modal distribution of aerosol volume size was observed with highest volume concentration during the post-monsoon season in fine mode and pre-monsoon season in coarse mode (Lumbini) and highest value over both modes during pre-monsoon season in Kathmandu. The single scattering albedo (SSA) and asymmetry parameter (AP) analyses suggested aerosols over the Himalayan foothills sites are dominated by absorbing and anthropogenic aerosols from urban and industrial activities and biomass burning. Long-term studies are essential to understand and characterize the nature of aerosol over this research gap zone.

Epstein-Barr virus infection and nasopharyngeal carcinoma.

PubMed

Tsao, Sai Wah; Tsang, Chi Man; Lo, Kwok Wai

2017-10-19

Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Author(s).

Probing the Molecular Outflows of the Coldest Known Object in the Universe: The Boomerang Nebula

NASA Astrophysics Data System (ADS)

Sahai, Raghvendra; Vlemmings, W.; Nyman, L. A.; Huggins, P.

2012-05-01

The Boomerang Nebula is the coldest known object in the Universe, and an extreme member of the class of Pre-Planetary Nebulae, objects which represent a short-lived transitional phase between the AGB and Planetary Nebula evolutionary stages. The Boomerang's estimated prodigious mass-loss rate (0.001 solar masses/year) and low-luminosity (300 Lsun) lack an explanation in terms of current paradigms for dusty mass-loss and standard evolutionary theory of intermediate-mass stars. Single-dish CO J=1-0 observations (with a 45 arcsec beam) show that the high-speed outflow in this object has cooled to a temperature significantly below the temperature of the cosmic background radiation. We report on our high-resolution ALMA mapping of the CO lines in this ultra-cold nebula to determine the origin of these extreme conditions and robustly confirm current estimates of the fundamental physical properties of its ultra-cold outflow.

Membrane rupture generates single open membrane sheets during vaccinia virus assembly.

PubMed

Chlanda, Petr; Carbajal, Maria Alejandra; Cyrklaff, Marek; Griffiths, Gareth; Krijnse-Locker, Jacomine

2009-07-23

The biogenesis and dynamics of cellular membranes are governed by fusion and fission processes that ensure the maintenance of closed compartments. These principles also apply to viruses during acquisition of their envelope. Based on conventional electron microscopy (EM), however, it has been proposed that poxviruses assemble from membranes made de novo with "free" ends in the cytoplasm. Here, we analyze the origin and structure of poxvirus membranes in a close-to-native state and in three dimensions by using cryopreservation and electron tomography (ET). By cryo-EM, the precursor membrane of poxviruses appears as an open membrane sheet stabilized by a protein scaffold. ET shows that this membrane is derived from pre-existing cellular membranes that rupture to generate an open compartment, rather than being made de novo. Thus, poxvirus infection represents an excellent system to study how cytoplasmic membranes can form open sheets by a process distinct from well-defined mechanisms of membrane biogenesis.

Development and Validation of a Spanish Version of the Grit-S Scale

PubMed Central

Arco-Tirado, Jose L.; Fernández-Martín, Francisco D.; Hoyle, Rick H.

2018-01-01

This paper describes the development and initial validation of a Spanish version of the Short Grit (Grit-S) Scale. The Grit-S Scale was adapted and translated into Spanish using the Translation, Review, Adjudication, Pre-testing, and Documentation model and responses to a preliminary set of items from a large sample of university students (N = 1,129). The resultant measure was validated using data from a large stratified random sample of young adults (N = 1,826). Initial validation involved evaluating the internal consistency of the adapted scale and its subscales and comparing the factor structure of the adapted version to that of the original scale. The results were comparable to results from similar analyses of the English version of the scale. Although the internal consistency of the subscales was low, the internal consistency of the full scale was well-within the acceptable range. A two-factor model offered an acceptable account of the data; however, when a single correlated error involving two highly similar items was included, a single factor model fit the data very well. The results support the use of overall scores from the Spanish Grit-S Scale in future research. PMID:29467705

Understanding auditory distance estimation by humpback whales: a computational approach.

PubMed

Mercado, E; Green, S R; Schneider, J N

2008-02-01

Ranging, the ability to judge the distance to a sound source, depends on the presence of predictable patterns of attenuation. We measured long-range sound propagation in coastal waters to assess whether humpback whales might use frequency degradation cues to range singing whales. Two types of neural networks, a multi-layer and a single-layer perceptron, were trained to classify recorded sounds by distance traveled based on their frequency content. The multi-layer network successfully classified received sounds, demonstrating that the distorting effects of underwater propagation on frequency content provide sufficient cues to estimate source distance. Normalizing received sounds with respect to ambient noise levels increased the accuracy of distance estimates by single-layer perceptrons, indicating that familiarity with background noise can potentially improve a listening whale's ability to range. To assess whether frequency patterns predictive of source distance were likely to be perceived by whales, recordings were pre-processed using a computational model of the humpback whale's peripheral auditory system. Although signals processed with this model contained less information than the original recordings, neural networks trained with these physiologically based representations estimated source distance more accurately, suggesting that listening whales should be able to range singers using distance-dependent changes in frequency content.

Single Group, Pre- and Post-Test Research Designs: Some Methodological Concerns

ERIC Educational Resources Information Center

Marsden, Emma; Torgerson, Carole J.

2012-01-01

This article provides two illustrations of some of the factors that can influence findings from pre- and post-test research designs in evaluation studies, including regression to the mean (RTM), maturation, history and test effects. The first illustration involves a re-analysis of data from a study by Marsden (2004), in which pre-test scores are…

40 CFR Appendix B to Part 434 - Baseline Determination and Compliance Monitoring for Pre-existing Discharges at Remining Operations

Code of Federal Regulations, 2014 CFR

2014-07-01

... Monitoring for Pre-existing Discharges at Remining Operations B Appendix B to Part 434 Protection of.... B Appendix B to Part 434—Baseline Determination and Compliance Monitoring for Pre-existing... monthly (single-observation) procedure and an annual procedure shall be applied, as described below. b. In...

A generalized parametric response mapping method for analysis of multi-parametric imaging: A feasibility study with application to glioblastoma.

PubMed

Lausch, Anthony; Yeung, Timothy Pok-Chi; Chen, Jeff; Law, Elton; Wang, Yong; Urbini, Benedetta; Donelli, Filippo; Manco, Luigi; Fainardi, Enrico; Lee, Ting-Yim; Wong, Eugene

2017-11-01

Parametric response map (PRM) analysis of functional imaging has been shown to be an effective tool for early prediction of cancer treatment outcomes and may also be well-suited toward guiding personalized adaptive radiotherapy (RT) strategies such as sub-volume boosting. However, the PRM method was primarily designed for analysis of longitudinally acquired pairs of single-parameter image data. The purpose of this study was to demonstrate the feasibility of a generalized parametric response map analysis framework, which enables analysis of multi-parametric data while maintaining the key advantages of the original PRM method. MRI-derived apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) maps acquired at 1 and 3-months post-RT for 19 patients with high-grade glioma were used to demonstrate the algorithm. Images were first co-registered and then standardized using normal tissue image intensity values. Tumor voxels were then plotted in a four-dimensional Cartesian space with coordinate values equal to a voxel's image intensity in each of the image volumes and an origin defined as the multi-parametric mean of normal tissue image intensity values. Voxel positions were orthogonally projected onto a line defined by the origin and a pre-determined response vector. The voxels are subsequently classified as positive, negative or nil, according to whether projected positions along the response vector exceeded a threshold distance from the origin. The response vector was selected by identifying the direction in which the standard deviation of tumor image intensity values was maximally different between responding and non-responding patients within a training dataset. Voxel classifications were visualized via familiar three-class response maps and then the fraction of tumor voxels associated with each of the classes was investigated for predictive utility analogous to the original PRM method. Independent PRM and MPRM analyses of the contrast-enhancing lesion (CEL) and a 1 cm shell of surrounding peri-tumoral tissue were performed. Prediction using tumor volume metrics was also investigated. Leave-one-out cross validation (LOOCV) was used in combination with permutation testing to assess preliminary predictive efficacy and estimate statistically robust P-values. The predictive endpoint was overall survival (OS) greater than or equal to the median OS of 18.2 months. Single-parameter PRM and multi-parametric response maps (MPRMs) were generated for each patient and used to predict OS via the LOOCV. Tumor volume metrics (P ≥ 0.071 ± 0.01) and single-parameter PRM analyses (P ≥ 0.170 ± 0.01) were not found to be predictive of OS within this study. MPRM analysis of the peri-tumoral region but not the CEL was found to be predictive of OS with a classification sensitivity, specificity and accuracy of 80%, 100%, and 89%, respectively (P = 0.001 ± 0.01). The feasibility of a generalized MPRM analysis framework was demonstrated with improved prediction of overall survival compared to the original single-parameter method when applied to a glioblastoma dataset. The proposed algorithm takes the spatial heterogeneity in multi-parametric response into consideration and enables visualization. MPRM analysis of peri-tumoral regions was shown to have predictive potential supporting further investigation of a larger glioblastoma dataset. © 2017 American Association of Physicists in Medicine.

Diffusion maps for high-dimensional single-cell analysis of differentiation data.

PubMed

Haghverdi, Laleh; Buettner, Florian; Theis, Fabian J

2015-09-15

Single-cell technologies have recently gained popularity in cellular differentiation studies regarding their ability to resolve potential heterogeneities in cell populations. Analyzing such high-dimensional single-cell data has its own statistical and computational challenges. Popular multivariate approaches are based on data normalization, followed by dimension reduction and clustering to identify subgroups. However, in the case of cellular differentiation, we would not expect clear clusters to be present but instead expect the cells to follow continuous branching lineages. Here, we propose the use of diffusion maps to deal with the problem of defining differentiation trajectories. We adapt this method to single-cell data by adequate choice of kernel width and inclusion of uncertainties or missing measurement values, which enables the establishment of a pseudotemporal ordering of single cells in a high-dimensional gene expression space. We expect this output to reflect cell differentiation trajectories, where the data originates from intrinsic diffusion-like dynamics. Starting from a pluripotent stage, cells move smoothly within the transcriptional landscape towards more differentiated states with some stochasticity along their path. We demonstrate the robustness of our method with respect to extrinsic noise (e.g. measurement noise) and sampling density heterogeneities on simulated toy data as well as two single-cell quantitative polymerase chain reaction datasets (i.e. mouse haematopoietic stem cells and mouse embryonic stem cells) and an RNA-Seq data of human pre-implantation embryos. We show that diffusion maps perform considerably better than Principal Component Analysis and are advantageous over other techniques for non-linear dimension reduction such as t-distributed Stochastic Neighbour Embedding for preserving the global structures and pseudotemporal ordering of cells. The Matlab implementation of diffusion maps for single-cell data is available at https://www.helmholtz-muenchen.de/icb/single-cell-diffusion-map. fbuettner.phys@gmail.com, fabian.theis@helmholtz-muenchen.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

"GFL2"! The Updated "Geography for Life: National Geography Standards, Second Edition"

ERIC Educational Resources Information Center

Heffron, Susan Gallagher

2012-01-01

"Geography for Life: National Geography Standards, Second Edition" ("GFL2") is the recently released update of the original edition published in 1994. The original edition of "Geography for Life" provided excellent guidance on geographic content for teachers, curriculum designers, publishers, and pre-service teachers as well as many other…

Mangala Valles, Mars: A reassessment of formation processes based on a new geomorphological and stratigraphic analysis of the geological units

NASA Astrophysics Data System (ADS)

Leone, Giovanni

2017-05-01

Mangala Valles has always been viewed as the typical outflow channel formed by catastrophic floods of water. A new analysis has shown that the geomorphological traces of fluvial or lacustrine processes within Mangala Valles can be better explained by fluid lava flooding the channels and filling pre-existing impact craters. As for the circum-Chryse outflow channels, where no clear source of water or mechanism able to replenish water at its hydraulic head is observed, there is no geologic trace of a sudden removal of a volume of water (ice) necessary to carve Mangala Valles. Neither maars nor rootless cones, typical volcanic features indicative of interaction between lava and ground ice, were found. Past works suggested that the formation of Mangala Valles occurred in late Amazonian age when the climate of Mars was similar to that seen today, that is absolutely not liquid water friendly. The present work shows how the origin of Mangala Valles may go back to Noachian or even Pre-Noachian when other studies have concluded that the climate was not liquid water friendly. Even assuming limited periods of obliquity favourable to liquid water in the history of Mars, which is at odds with the widespread presence of unaltered olivine and jarosite, it is very difficult to find plausible mechanisms of aquifer recharge or signs of catastrophic water release at the Notch of Mangala Valles that could feed the multiple episodes, or even a single episode, of fluvial flooding suggested in the literature. This evidence and other analysis will show that the presence of water and, eventually, ground ice is not incontrovertible in the equatorial regions and should not be given for granted as commonly done so far in the literature. The geomorphological analysis of the Mars Reconnaissance Orbiter (MRO) images provided in this paper, combined with THEMIS and MOLA data, show how Mangala Fossa, from which Mangala Valles originated as a breakout, is an erosional channel formed by the flow of lava in a original tube coming from Daedalia Planum rather than a tectonic graben or the sign of a dike rupturing to the surface.

Reversibly constraining spliceosome-substrate complexes by engineering disulfide crosslinks.

PubMed

McCarthy, Patrick; Garside, Erin; Meschede-Krasa, Yonatan; MacMillan, Andrew; Pomeranz Krummel, Daniel

2017-08-01

The spliceosome is a highly dynamic mega-Dalton enzyme, formed in part by assembly of U snRNPs onto its pre-mRNA substrate transcripts. Early steps in spliceosome assembly are challenging to study biochemically and structurally due to compositional and conformational dynamics. We detail an approach to covalently and reversibly constrain or trap non-covalent pre-mRNA/protein spliceosome complexes. This approach involves engineering a single disulfide bond between a thiol-bearing cysteine sidechain and a proximal backbone phosphate of the pre-mRNA, site-specifically modified with an N-thioalkyl moiety. When distance and angle between reactants is optimal, the sidechain will react with the single N-thioalkyl to form a crosslink upon oxidation. We provide protocols detailing how this has been applied successfully to trap an 11-subunit RNA-protein assembly, the human U1 snRNP, in complex with a pre-mRNA. Copyright © 2017 Elsevier Inc. All rights reserved.

Pre-Steady-State Kinetic Analysis of Single-Nucleotide Incorporation by DNA Polymerases

PubMed Central

Su, Yan; Guengerich, F. Peter

2016-01-01

Pre-steady-state kinetic analysis is a powerful and widely used method to obtain multiple kinetic parameters. This protocol provides a step-by-step procedure for pre-steady-state kinetic analysis of single-nucleotide incorporation by a DNA polymerase. It describes the experimental details of DNA substrate annealing, reaction mixture preparation, handling of the RQF-3 rapid quench-flow instrument, denaturing polyacrylamide DNA gel preparation, electrophoresis, quantitation, and data analysis. The core and unique part of this protocol is the rationale for preparation of the reaction mixture (the ratio of the polymerase to the DNA substrate) and methods for conducting pre-steady-state assays on an RQF-3 rapid quench-flow instrument, as well as data interpretation after analysis. In addition, the methods for the DNA substrate annealing and DNA polyacrylamide gel preparation, electrophoresis, quantitation and analysis are suitable for use in other studies. PMID:27248785

A probable case of congenital syphilis from pre-Columbian Austria.

PubMed

Gaul, Johanna Sophia; Grossschmidt, Karl; Gusenbauer, Christian; Kanz, Fabian

2015-01-01

This study examines the skeletal remains of a subadult from an archeological site in Austria. Radiocarbon dating and archeological attribution indicate that this individual is of pre-Columbian origin. Most of the skeleton was recovered, and only the teeth and the orbital roofs show changes. Dental defects such as the mulberry molar and a tapered, fang-like canine suggest a diagnosis of congenital syphilis. This is the first probable case of congenital syphilis from pre-Columbian Central Europe. Our findings contribute to the pre-Columbian theory, offering counter evidence to the assumption that syphilis was carried from Columbus' crew from the New to the Old World.

Pre-equilibrium Longitudinal Flow in the IP-Glasma Framework for Pb+Pb Collisions at the LHC

NASA Astrophysics Data System (ADS)

McDonald, Scott; Shen, Chun; Fillion-Gourdeau, François; Jeon, Sangyong; Gale, Charles

2017-08-01

In this work, we debut a new implementation of IP-Glasma and quantify the pre-equilibrium longitudinal flow in the IP-Glasma framework. The saturation physics based IP-Glasma model naturally provides a non-zero initial longitudinal flow through its pre-equilibrium Yang-Mills evolution. A hybrid IP-Glasma+MUSIC+UrQMD frame-work is employed to test this new implementation against experimental data and to make further predictions about hadronic flow observables in Pb+Pb collisions at 5.02 TeV. Finally, the non-zero pre-equilibrium longitudinal flow of the IP-Glasma model is quantified, and its origin is briefly discussed.

Mapping yeast origins of replication via single-stranded DNA detection.

PubMed

Feng, Wenyi; Raghuraman, M K; Brewer, Bonita J

2007-02-01

Studies in th Saccharomyces cerevisiae have provided a framework for understanding how eukaryotic cells replicate their chromosomal DNA to ensure faithful transmission of genetic information to their daughter cells. In particular, S. cerevisiae is the first eukaryote to have its origins of replication mapped on a genomic scale, by three independent groups using three different microarray-based approaches. Here we describe a new technique of origin mapping via detection of single-stranded DNA in yeast. This method not only identified the majority of previously discovered origins, but also detected new ones. We have also shown that this technique can identify origins in Schizosaccharomyces pombe, illustrating the utility of this method for origin mapping in other eukaryotes.

Molecular recognition of pre-tRNA by Arabidopsis protein-only Ribonuclease P.

PubMed

Klemm, Bradley P; Karasik, Agnes; Kaitany, Kipchumba J; Shanmuganathan, Aranganathan; Henley, Matthew J; Thelen, Adam Z; Dewar, Allison J L; Jackson, Nathaniel D; Koutmos, Markos; Fierke, Carol A

2017-12-01

Protein-only ribonuclease P (PRORP) is an enzyme responsible for catalyzing the 5' end maturation of precursor transfer ribonucleic acids (pre-tRNAs) encoded by various cellular compartments in many eukaryotes. PRORPs from plants act as single-subunit enzymes and have been used as a model system for analyzing the function of the metazoan PRORP nuclease subunit, which requires two additional proteins for efficient catalysis. There are currently few molecular details known about the PRORP-pre-tRNA complex. Here, we characterize the determinants of substrate recognition by the single subunit Arabidopsis thaliana PRORP1 and PRORP2 using kinetic and thermodynamic experiments. The salt dependence of binding affinity suggests 4-5 contacts with backbone phosphodiester bonds on substrates, including a single phosphodiester contact with the pre-tRNA 5' leader, consistent with prior reports of short leader requirements. PRORPs contain an N-terminal pentatricopeptide repeat (PPR) domain, truncation of which results in a >30-fold decrease in substrate affinity. While most PPR-containing proteins have been implicated in single-stranded sequence-specific RNA recognition, we find that the PPR motifs of PRORPs recognize pre-tRNA substrates differently. Notably, the PPR domain residues most important for substrate binding in PRORPs do not correspond to positions involved in base recognition in other PPR proteins. Several of these residues are highly conserved in PRORPs from algae, plants, and metazoans, suggesting a conserved strategy for substrate recognition by the PRORP PPR domain. Furthermore, there is no evidence for sequence-specific interactions. This work clarifies molecular determinants of PRORP-substrate recognition and provides a new predictive model for the PRORP-substrate complex. © 2017 Klemm et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Acute response of plasma markers of bone turnover to a single bout of resistance training or plyometrics.

PubMed

Rogers, Robert S; Dawson, Andrew W; Wang, Ze; Thyfault, John P; Hinton, Pamela S

2011-11-01

The time course of changes in plasma bone turnover markers following an acute bout of resistance training (RT) or plyometrics (PLY) has not been well characterized. This study is the first to compare the acute response of bone formation and resorption markers to a single bout of RT or PLY. Using a partially randomized, cross-over study design, 12 recreationally active men, aged 43 ± 5 yr, each completed four exercise trials: RT (Fed/Fasted) and PLY (Fed/Fasted). In addition to the RT and PLY trials, 5 of the original 12 participants also completed a fasted, no-exercise control trial to examine time-of-day variation. For each trial, blood was drawn immediately before exercise (PRE), immediately following exercise, and 15 min, 30 min, 1 h, 2 h, and 24 h following PRE for determination of plasma bone-specific alkaline phosphatase (BAP), osteocalcin (OC), tartrate-resistant acid phosphatase 5b (TRAP5b), COOH-terminal telopeptide of type I collagen (CTX), testosterone, parathyroid hormone, and cortisol. A one-factor repeated-measures ANOVA was performed for each trial to detect changes in bone markers during the 2 h following RT or PLY. TRAP5b transiently decreased during the 2 h following all exercise trials (main effect for time, P < 0.05), but returned to PRE concentrations 2 h postexercise. BAP, CTX, and OC remained unchanged, except for reductions in BAP and CTX following PLY-Fasted and PLY-Fed, respectively. During the control trial, BAP decreased, while TRAP5b, CTX, and OC remained unchanged. In general, plasma hormone concentrations decreased during the 2 h following PLY or RT, and cumulative decreases in TRAP5b during the 2 h following exercise were positively correlated with cumulative decreases in parathyroid hormone. The results of the present study suggest that the timing of the measurement of bone turnover markers relative to the last exercise bout is important for detection of exercise-associated changes in bone turnover markers, as the markers returned to preexercise values within 2 h of RT or PLY.

Pre-integrated structures for Space Station Freedom

NASA Technical Reports Server (NTRS)

Cruz, Jonathan N.; Monell, Donald W.; Mutton, Philip; Troutman, Patrick A.

1991-01-01

An in-space construction (erectable) approach to assembling Freedom is planned but the increasing complexity of the station design along with a decrease in shuttle capability over the past several years has led to an assembly sequence that requires more resources (EVA, lift, volume) than the shuttle can provide given a fixed number of flights. One way to address these issues is to adopt a pre-integrated approach to assembling Freedom. A pre-integrated approach combines station primary structure and distributed systems into discrete sections that are assembled and checked out on the ground. The section is then launched as a single structural entity on the shuttle and attached to the orbiting station is then launched as a single structural entity on the shuttle and attached to the orbiting station with a minimum of EVA. The feasibility of a pre-integrated approach to assembling Freedon is discussed. The structural configuration, packaging, and shuttle integration of discrete pre-integrated elements for Freedom assembly are discussed. It is shown that the pre-integrated approach to assembly reduces EVA and increases shuttle margin with respect to mass, volume, and center of gravity limits when compared to the baseline Freedom assembly sequence.

The evolution of floral scent and olfactory preferences in pollinators: coevolution or pre-existing bias?

PubMed

Schiestl, Florian P; Dötterl, Stefan

2012-07-01

Coevolution is thought to be a major factor in shaping plant-pollinator interactions. Alternatively, plants may have evolved traits that fitted pre-existing preferences or morphologies in the pollinators. Here, we test these two scenarios in the plant family of Araceae and scarab beetles (Coleoptera, Scarabaeidae) as pollinators. We focused on floral volatile organic compounds (VOCs) and production/detection of VOCs by scarab beetles. We found phylogenetic structure in the production/detection of methoxylated aromatics in scarabs, but not plants. Within the plants, most of the compounds showed a well-supported pattern of correlated evolution with scarab-beetle pollination. In contrast, the scarabs showed no correlation between VOC production/detection and visitation to Araceae flowers, with the exception of the VOC skatole. Moreover, many VOCs were found in nonpollinating beetle groups (e.g., Melolonthinae) that are ancestors of pollinating scarabs. Importantly, none of the tested VOCs were found to have originated in pollinating taxa. Our analysis indicates a Jurassic origin of VOC production/detection in scarabs, but a Cretaceous/Paleocene origin of floral VOCs in plants. Therefore, we argue against coevolution, instead supporting the scenario of sequential evolution of floral VOCs in Araceae driven by pre-existing bias of pollinators. © 2012 The Author(s).

The Child Suicide Risk Assessment: A Screening Measure of Suicide Risk in Pre-Adolescents

ERIC Educational Resources Information Center

Larzelere, Robert E.; Andersen, Jamie J.; Ringle, Jay L.; Jorgensen, Dan D.

2004-01-01

This study documents the initial reliability and validity of the Child Suicide Risk Assessment (CSRA) for children under the age of 13. The revised CSRA retained 18 of 20 original items based on item-specific psychometric data from 140 pre-adolescents in out-of-home treatment programs. The CSRA demonstrated adequate internal consistency (alpha =…

The Origins of Molecular Biology: A Pedagogical Tool for the Professional Development of Pre-College Science Teachers

ERIC Educational Resources Information Center

Silverman, Philip M.

2003-01-01

We examine the science and pedagogy behind a historical approach to the professional development of pre-college science (primarily biology) teachers. Our intention is to reach professional scientists, who, as a group, are uniquely qualified to provide experience and insights essential to this approach. The underlying research for this article has…

"With Percentages the 100 Is Always in the Denominator": From the Field to Pre-Service Teachers

ERIC Educational Resources Information Center

Cincinatus, Ronit Bassan; Sheffet, Malka

2016-01-01

The ubiquity of the subject of percentages in our everyday life demands that math teachers and pre-service math teachers demonstrate a profound knowledge and thorough understanding of the concept of percentages. This work, which originated from one specific lesson in an 8th grade math class, studies the conceptual understanding and problem-solving…

Efficacy of the Lexicon Pirate Strategy Therapy for Improving Lexical Learning in School-Age Children: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Motsch, Hans-Joachim; Marks, Dana-Kristin

2015-01-01

Lexicon Pirate was originally developed as a strategy intervention programme to treat lexical disorders of pre-school children. To evaluate the therapy's effectiveness for school-age students, a randomized controlled trial (RCT, N = 157) was conducted. Based on a pre--post-test design, the programme's impacts were compared with a control group…

Early Writing among Ancient Vikings and Today's Pre-Schoolers: A Cognitive Developmental Perspective on Reading Acquisition and Alphabets as Effective Artefacts

ERIC Educational Resources Information Center

Olofsson, Ake

2008-01-01

The present paper reports some observations on pre-school children's spontaneous as well as adult-supported spelling behaviour and makes comparisons between aspects of these early literacy activities and some features of spellings from mostly twelfth- to fourteenth-century Norwegian runic inscriptions. The runic inscriptions originate from a…

An enhanced TIMESAT algorithm for estimating vegetation phenology metrics from MODIS data

USGS Publications Warehouse

Tan, B.; Morisette, J.T.; Wolfe, R.E.; Gao, F.; Ederer, G.A.; Nightingale, J.; Pedelty, J.A.

2011-01-01

An enhanced TIMESAT algorithm was developed for retrieving vegetation phenology metrics from 250 m and 500 m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indexes (VI) over North America. MODIS VI data were pre-processed using snow-cover and land surface temperature data, and temporally smoothed with the enhanced TIMESAT algorithm. An objective third derivative test was applied to define key phenology dates and retrieve a set of phenology metrics. This algorithm has been applied to two MODIS VIs: Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). In this paper, we describe the algorithm and use EVI as an example to compare three sets of TIMESAT algorithm/MODIS VI combinations: a) original TIMESAT algorithm with original MODIS VI, b) original TIMESAT algorithm with pre-processed MODIS VI, and c) enhanced TIMESAT and pre-processed MODIS VI. All retrievals were compared with ground phenology observations, some made available through the National Phenology Network. Our results show that for MODIS data in middle to high latitude regions, snow and land surface temperature information is critical in retrieving phenology metrics from satellite observations. The results also show that the enhanced TIMESAT algorithm can better accommodate growing season start and end dates that vary significantly from year to year. The TIMESAT algorithm improvements contribute to more spatial coverage and more accurate retrievals of the phenology metrics. Among three sets of TIMESAT/MODIS VI combinations, the start of the growing season metric predicted by the enhanced TIMESAT algorithm using pre-processed MODIS VIs has the best associations with ground observed vegetation greenup dates. ?? 2010 IEEE.

An Enhanced TIMESAT Algorithm for Estimating Vegetation Phenology Metrics from MODIS Data

NASA Technical Reports Server (NTRS)

Tan, Bin; Morisette, Jeffrey T.; Wolfe, Robert E.; Gao, Feng; Ederer, Gregory A.; Nightingale, Joanne; Pedelty, Jeffrey A.

2012-01-01

An enhanced TIMESAT algorithm was developed for retrieving vegetation phenology metrics from 250 m and 500 m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indexes (VI) over North America. MODIS VI data were pre-processed using snow-cover and land surface temperature data, and temporally smoothed with the enhanced TIMESAT algorithm. An objective third derivative test was applied to define key phenology dates and retrieve a set of phenology metrics. This algorithm has been applied to two MODIS VIs: Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). In this paper, we describe the algorithm and use EVI as an example to compare three sets of TIMESAT algorithm/MODIS VI combinations: a) original TIMESAT algorithm with original MODIS VI, b) original TIMESAT algorithm with pre-processed MODIS VI, and c) enhanced TIMESAT and pre-processed MODIS VI. All retrievals were compared with ground phenology observations, some made available through the National Phenology Network. Our results show that for MODIS data in middle to high latitude regions, snow and land surface temperature information is critical in retrieving phenology metrics from satellite observations. The results also show that the enhanced TIMESAT algorithm can better accommodate growing season start and end dates that vary significantly from year to year. The TIMESAT algorithm improvements contribute to more spatial coverage and more accurate retrievals of the phenology metrics. Among three sets of TIMESAT/MODIS VI combinations, the start of the growing season metric predicted by the enhanced TIMESAT algorithm using pre-processed MODIS VIs has the best associations with ground observed vegetation greenup dates.

Single Molecule Cluster Analysis Identifies Signature Dynamic Conformations along the Splicing Pathway

PubMed Central

Blanco, Mario R.; Martin, Joshua S.; Kahlscheuer, Matthew L.; Krishnan, Ramya; Abelson, John; Laederach, Alain; Walter, Nils G.

2016-01-01

The spliceosome is the dynamic RNA-protein machine responsible for faithfully splicing introns from precursor messenger RNAs (pre-mRNAs). Many of the dynamic processes required for the proper assembly, catalytic activation, and disassembly of the spliceosome as it acts on its pre-mRNA substrate remain poorly understood, a challenge that persists for many biomolecular machines. Here, we developed a fluorescence-based Single Molecule Cluster Analysis (SiMCAn) tool to dissect the manifold conformational dynamics of a pre-mRNA through the splicing cycle. By clustering common dynamic behaviors derived from selectively blocked splicing reactions, SiMCAn was able to identify signature conformations and dynamic behaviors of multiple ATP-dependent intermediates. In addition, it identified a conformation adopted late in splicing by a 3′ splice site mutant, invoking a mechanism for substrate proofreading. SiMCAn presents a novel framework for interpreting complex single molecule behaviors that should prove widely useful for the comprehensive analysis of a plethora of dynamic cellular machines. PMID:26414013

Using Single-trial EEG to Predict and Analyze Subsequent Memory

PubMed Central

Noh, Eunho; Herzmann, Grit; Curran, Tim; de Sa, Virginia R.

2013-01-01

We show that it is possible to successfully predict subsequent memory performance based on single-trial EEG activity before and during item presentation in the study phase. Two-class classification was conducted to predict subsequently remembered vs. forgotten trials based on subjects’ responses in the recognition phase. The overall accuracy across 18 subjects was 59.6 % by combining pre- and during-stimulus information. The single-trial classification analysis provides a dimensionality reduction method to project the high-dimensional EEG data onto a discriminative space. These projections revealed novel findings in the pre- and during-stimulus period related to levels of encoding. It was observed that the pre-stimulus information (specifically oscillatory activity between 25–35Hz) −300 to 0 ms before stimulus presentation and during-stimulus alpha (7–12 Hz) information between 1000–1400 ms after stimulus onset distinguished between recollection and familiarity while the during-stimulus alpha information and temporal information between 400–800 ms after stimulus onset mapped these two states to similar values. PMID:24064073

Patient-specific surgical simulator for the pre-operative planning of single-incision laparoscopic surgery with bimanual robots.

PubMed

Turini, Giuseppe; Moglia, Andrea; Ferrari, Vincenzo; Ferrari, Mauro; Mosca, Franco

2012-01-01

The trend of surgical robotics is to follow the evolution of laparoscopy, which is now moving towards single-incision laparoscopic surgery. The main drawback of this approach is the limited maneuverability of the surgical tools. Promising solutions to improve the surgeon's dexterity are based on bimanual robots. However, since both robot arms are completely inserted into the patient's body, issues related to possible unwanted collisions with structures adjacent to the target organ may arise. This paper presents a simulator based on patient-specific data for the positioning and workspace evaluation of bimanual surgical robots in the pre-operative planning of single-incision laparoscopic surgery. The simulator, designed for the pre-operative planning of robotic laparoscopic interventions, was tested by five expert surgeons who evaluated its main functionalities and provided an overall rating for the system. The proposed system demonstrated good performance and usability, and was designed to integrate both present and future bimanual surgical robots.

Pre-Exposure Prophylaxis YouTube Videos: Content Evaluation.

PubMed

Kecojevic, Aleksandar; Basch, Corey; Basch, Charles; Kernan, William

2018-02-16

Antiretroviral (ARV) medicines reduce the risk of transmitting the HIV virus and are recommended as daily pre-exposure prophylaxis (PrEP) in combination with safer sex practices for HIV-negative individuals at a high risk for infection, but are underused in HIV prevention. Previous literature suggests that YouTube is extensively used to share health information. While pre-exposure prophylaxis (PrEP) is a novel and promising approach to HIV prevention, there is limited understanding of YouTube videos as a source of information on PrEP. The objective of this study was to describe the sources, characteristics, and content of the most widely viewed PrEP YouTube videos published up to October 1, 2016. The keywords "pre-exposure prophylaxis" and "Truvada" were used to find 217 videos with a view count >100. Videos were coded for source, view count, length, number of comments, and selected aspects of content. Videos were also assessed for the most likely target audience. The total cumulative number of views was >2.3 million, however, a single Centers for Disease Control and Prevention video accounted for >1.2 million of the total cumulative views. A great majority (181/217, 83.4%) of the videos promoted the use of PrEP, whereas 60.8% (132/217) identified the specific target audience. In contrast, only 35.9% (78/217) of the videos mentioned how to obtain PrEP, whereas less than one third addressed the costs, side effects, and safety aspects relating to PrEP. Medical and academic institutions were the sources of the largest number of videos (66/217, 30.4%), followed by consumers (63/217, 29.0%), community-based organizations (CBO; 48/217, 22.1%), and media (40/217, 18.4%). Videos uploaded by the media sources were more likely to discuss the cost of PrEP (P<.001), whereas the use of PrEP was less likely to be promoted in videos uploaded by individual consumers (P=.002) and more likely to be promoted in videos originated by CBOs (P=.009). The most common target audience for the videos was gay and bisexual men. YouTube videos can be used to share reliable PrEP information with individuals. Further research is needed to identify the best practices for using this medium to promote and increase PrEP uptake. ©Aleksandar Kecojevic, Corey Basch, Charles Basch, William Kernan. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 16.02.2018.

The Macromolecular Concept and the Origins of Molecular Biology

ERIC Educational Resources Information Center

Olby, Robert

1970-01-01

Traces the origins of molecular biology to the work of 19th century biophysicists, ultrastructurists and collodial chemists. The development of the Aggregate Theory,and its overthrow by the Macromolecule Concept is described. Research in molecular genetics in the pre-second world war period, and the effects of the war on it, are briefly reviewed.…

Working in the Methodological "Outfield": The Case of Bourdieu and Occupational Therapy

ERIC Educational Resources Information Center

Watson, Jo; Grenfell, Michael

2016-01-01

The article reports on a study of methodological innovation involving occupational therapy (OT) students in higher education (HE). It is based on an original project which examined the experiences and outcomes of non-traditional entrants to pre-registration OT education. A feature of the original project was the application of the epistemological…

12. Photocopy of antique postcard. (Original postcard is in the ...

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

12. Photocopy of antique postcard. (Original postcard is in the possession of the Venice Branch of the Los Angeles Public Library, publisher/photographer unknown.) VIEW OF PRE-EXISTING GRAND CANAL COURT PEDESTRIAN BRIDGE OVER CARROLL CANAL, LOOKING EAST TOWARD DELL AVENUE VEHICULAR BRIDGE - Venice Canals, Community of Venice, Los Angeles, Los Angeles County, CA

[Merkel cell carcinoma: cutaneous manifestation of a highly malignant pre-/pro-B cell neoplasia? : Novel concept about the cellular origin of Merkel cell carcinoma].

PubMed

Sauer, C M; Chteinberg, E; Rennspiess, D; Kurz, A K; Zur Hausen, A

2017-03-01

Merkel cell carcinoma (MCC) is a relatively rare but highly malignant non-melanoma skin cancer of the elderly and immunosuppressed patients. The discovery of the Merkel cell polyomavirus (MCPyV) in 2008 significantly impacted the understanding of the etiopathogenesis of MCC. MCPyV is clonally integrated into the MCC genome and approximately 80% of MCC are MCPyV-positive. Recent results of clinical trials using blockade of the PD-1 immune modulatory pathway are promising for the future treatment of MCC. Despite this major progress of the past few years, the cellular origin of MCC still remains obscure. Based on histomorphology, gene expression profiling, and molecular analyses, we have recently hypothesized that MCC originates from pre‑/pro-B cells. Here we review putative cells of MCC, including Merkel cells, (epi‑)dermal stem cells, and pro‑/pre-B cells. In the present work, the focus is on the concept of pre‑/pro-B cells as the cellular origin of MCC, which might also impact the understanding of other human small cell malignancies of unknown cellular origin, such as small cell carcinomas of the lung and other anatomical locations. In addition, this concept might pave the way for novel treatment options, especially for advanced MCC.

Applicability of an established management algorithm for destructive colon injuries after abbreviated laparotomy: a 17-year experience.

PubMed

Sharpe, John P; Magnotti, Louis J; Weinberg, Jordan A; Shahan, Charles P; Cullinan, Darren R; Marino, Katy A; Fabian, Timothy C; Croce, Martin A

2014-04-01

For more than a decade, operative decisions (resection plus anastomosis vs diversion) for colon injuries, at our institution, have followed a defined management algorithm based on established risk factors (pre- or intraoperative transfusion requirements of more than 6 units packed RBCs and/or presence of significant comorbid diseases). However, this management algorithm was originally developed for patients managed with a single laparotomy. The purpose of this study was to evaluate the applicability of this algorithm to destructive colon injuries after abbreviated laparotomy (AL) and to determine whether additional risk factors should be considered. Consecutive patients over a 17-year period with colon injuries after AL were identified. Nondestructive injuries were managed with primary repair. Destructive wounds were resected at the initial laparotomy followed by either a staged diversion (SD) or a delayed anastomosis (DA) at the subsequent exploration. Outcomes were evaluated to identify additional risk factors in the setting of AL. We identified 149 patients: 33 (22%) patients underwent primary repair at initial exploration, 42 (28%) underwent DA, and 72 (49%) had SD. Two (1%) patients died before re-exploration. Of those undergoing DA, 23 (55%) patients were managed according to the algorithm and 19 (45%) were not. Adherence to the algorithm resulted in lower rates of suture line failure (4% vs 32%, p = 0.03) and colon-related morbidity (22% vs 58%, p = 0.03) for patients undergoing DA. No additional specific risk factors for suture line failure after DA were identified. Adherence to an established algorithm, originally defined for destructive colon injuries after single laparotomy, is likewise efficacious for the management of these injuries in the setting of AL. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Variability of single bean coffee volatile compounds of Arabica and robusta roasted coffees analysed by SPME-GC-MS.

PubMed

Caporaso, Nicola; Whitworth, Martin B; Cui, Chenhao; Fisk, Ian D

2018-06-01

We report on the analysis of volatile compounds by SPME-GC-MS for individual roasted coffee beans. The aim was to understand the relative abundance and variability of volatile compounds between individual roasted coffee beans at constant roasting conditions. Twenty-five batches of Arabica and robusta species were sampled from 13 countries, and 10 single coffee beans randomly selected from each batch were individually roasted in a fluidised-bed roaster at 210 °C for 3 min. High variability (CV = 14.0-53.3%) of 50 volatile compounds in roasted coffee was obtained within batches (10 beans per batch). Phenols and heterocyclic nitrogen compounds generally had higher intra-batch variation, while ketones were the most uniform compounds (CV < 20%). The variation between batches was much higher, with the CV ranging from 15.6 to 179.3%. The highest variation was observed for 2,3-butanediol, 3-ethylpyridine and hexanal. It was also possible to build classification models based on geographical origin, obtaining 99.5% and 90.8% accuracy using LDA or MLR classifiers respectively, and classification between Arabica and robusta beans. These results give further insight into natural variation of coffee aroma and could be used to obtain higher quality and more consistent final products. Our results suggest that coffee volatile concentration is also influenced by other factors than simply the roasting degree, especially green coffee composition, which is in turn influenced by the coffee species, geographical origin, ripening stage and pre- and post-harvest processing. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Seismogenic structures activated during the pre-eruptive and intrusive swarms of Piton de la Fournaise volcano (La Réunion island) between 2008 and 2011

NASA Astrophysics Data System (ADS)

Battaglia, J.; Brenguier, F.

2011-12-01

Piton de la Fournaise is a frequently active basaltic volcano with more than 30 fissure eruptions since 1998. These eruptions are always preceded by pre-eruptive swarms of volcano-tectonic earthquakes which accompany dike propagation. Occasionally, intrusion swarms occur without leading to any eruption. From October 2008 to May 2011, as part of the research project Undervolc, a temporary network of 15 broadband stations has been installed on the volcano to complement the local monitoring network. We examined in detail the 6 intrusive and 5 pre-eruptive swarms which occurred during the temporary experiment. All the crises lasted for a few hours and only included shallow events clustered below the summit craters, around and above sea level, showing no signs of deeper magma transfers. These characteristics are common to most swarms observed at Piton de la Fournaise arising questions about the origin of the seismicity which seems to be poorly linked with dike propagation. With the aim to identify the main seismogenic structures active during the swarms, we applied precise earthquake detection and classification techniques based on waveform cross-correlation. For each swarm, the onsets of all transients, including small amplitude ones, have been precisely detected at a single station by scanning the continuous data with reference waveforms. The classification of the detected transients indicates the presence of several families of similar earthquakes. The two main families (F01 and F02) include several hundred events. They are systematically activated at the beginning of each pre-eruptive swarm but are inactive during the intrusive ones. They group more than 50 percent of the detected events for the corresponding crises. The other clusters are mostly associated with single swarms. To determine the spatial characteristics of the structures corresponding to the main families, we applied precise relocation techniques. Based on the one-station classification, the events have first been picked at all available stations by cross-correlating waveforms with those of master events whose arrival times have been manually determined. All events have been located using a 3D velocity model to determine accurate hypocentral azimuths and take-off angles. Precise relative locations have been computed for each multiplet using cross-correlation delays calculated for all available stations between all pairs of events. The results indicate the presence at sea level of a major structure grouping families F01 and F02 and describing an East-West elongated pattern with sub-vertical extension. Small scale earthquake migrations, mostly horizontal, occur during the pre-eruptive swarms along that structure. The smaller multiplets define vertically elongated patterns extending around and above the main F01-F02 multiplet. Our results show that different processes are involved in pre-eruptive and intrusive crises and that a structure located around 2.5 km below the summit controls the occurrence of recent eruptions of Piton de la Fournaise volcano.

Strontium Isotopes and the Reconstruction of the Chaco Regional System: Evaluating Uncertainty with Bayesian Mixing Models

PubMed Central

Drake, Brandon Lee; Wills, Wirt H.; Hamilton, Marian I.; Dorshow, Wetherbee

2014-01-01

Strontium isotope sourcing has become a common and useful method for assigning sources to archaeological artifacts. In Chaco Canyon, an Ancestral Pueblo regional center in New Mexico, previous studies using these methods have suggested that significant portion of maize and wood originate in the Chuska Mountains region, 75 km to the East. In the present manuscript, these results were tested using both frequentist methods (to determine if geochemical sources can truly be differentiated) and Bayesian methods (to address uncertainty in geochemical source attribution). It was found that Chaco Canyon and the Chuska Mountain region are not easily distinguishable based on radiogenic strontium isotope values. The strontium profiles of many geochemical sources in the region overlap, making it difficult to definitively identify any one particular geochemical source for the canyon's pre-historic maize. Bayesian mixing models support the argument that some spruce and fir wood originated in the San Mateo Mountains, but that this cannot explain all 87Sr/86Sr values in Chaco timber. Overall radiogenic strontium isotope data do not clearly identify a single major geochemical source for maize, ponderosa, and most spruce/fir timber. As such, the degree to which Chaco Canyon relied upon outside support for both food and construction material is still ambiguous. PMID:24854352

Monitoring single coffee bean roasting by direct volatile compound analysis with proton transfer reaction time-of-flight mass spectrometry.

PubMed

Yener, Sine; Navarini, Luciano; Lonzarich, Valentina; Cappellin, Luca; Märk, Tilmann D; Bonn, Günther K; Biasioli, Franco

2016-09-01

This study applies proton transfer reaction time-of-flight mass spectrometry for the rapid analysis of volatile compounds released from single coffee beans. The headspace volatile profiles of single coffee beans (Coffeea arabica) from different geographical origins (Brazil, Guatemala and Ethiopia) were analyzed via offline profiling at different stages of roasting. The effect of coffee geographical origin was reflected on volatile compound formation that was supported by one-way ANOVA. Clear origin signatures were observed in the formation of different coffee odorants. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Supporting Transition or Playing Catch-Up in Grade 4? Implications for Standards in Education and Training

ERIC Educational Resources Information Center

Pretorius, Elizabeth J.

2014-01-01

This paper describes an intervention programme that was originally intended to support transition to English as language of learning and teaching (LoLT) in Grade 4 in a township school, using a pre- and post-test design. Because the pre-tests revealed very poor literacy levels in both Zulu home language and English, the intervention programme was…

Social, moral, and temporal qualities: Pre-service teachers' considerations of evolution and creation

NASA Astrophysics Data System (ADS)

Hahn, Deirdre

The introduction of the theories of evolution into public education has created a history of misinterpretation and uncertainty about its application to understanding deep time and human origins. Conceptions about negative social and moral outcomes of evolution itself along with cognitive temporal constraints may be difficult for many individuals to uncouple from the scientific theory, serving to provoke the ongoing debate about the treatment of evolution in science education. This debate about teaching evolution is strongly influenced by groups who strive to add creationism to the science curriculum for a balanced treatment of human origins and to mediate implied negative social and moral outcomes of evolution. Individual conceptualization of evolution and creation may influence the choice of college students to teach science. This study is designed to examine if pre-service teachers' conceptualize an evolutionary and creationist process of human development using certain social, moral or temporal patterns; and if the patterns follow a negative conceptual theme. The pilot study explored 21 pre-service teachers' conceptual representation of an evolutionary process through personal narratives. Participants tended to link evolutionary changes with negative social and moral consequences and seemed to have difficulty envisioning change over time. The pilot study was expanded to include a quantitative examination of attribute patterns of an evolutionary and creationist developmental process. Seventy-three pre-service teachers participated in the second experiment and tended to fall evenly along a continuum of creationist and evolutionist beliefs about life. Using a chi-square and principle components analysis, participants were found to map concepts of evolution and creation onto each other using troubling attributes of development to distinguish negative change over time. A strong negative social and moral pattern of human development was found in the creation condition, though only a vague negative human developmental process was found for the evolution condition. Based on these results, pre-service teachers may not use evolution as a viable explanation of human origins, which may serve to contribute to evolution theory debates and discourage pre-service teachers' choice of being science instructors.

The central uplift of Elorza Crater: Insights into its geology and possible relationships to the Valles Marineris and Tharsis regions

NASA Astrophysics Data System (ADS)

Hopkins, R. T.; Tornabene, L. L.; Osinski, G. R.

2017-03-01

The majority of hydrated silicate occurrences on Mars are associated with impact craters (Ehlmann et al., 2011; Carter et al., 2013). Three formation mechanisms have been suggested to account for this correlation: (1) aqueous alteration occurred pre-impact, and was subsequently exposed via the impact (pre-impact; Bibring et al., 2006; Ehlmann et al., 2011), (2) heat generated from the impact facilitated the formation of a hydrothermal system, leading to alteration products (syn-impact; e.g. Marzo et al., 2010; Osinski et al., 2013), and/or (3) altered materials were deposited after crater formation, or formed within the crater well after the impact had taken place (post-impact). In this study, we analyze the central uplift of Elorza Crater, a ∼40 km diameter impact crater located ∼300 km north of Valles Marineris. To determine whether hydrated minerals found within the uplift were generated pre-, syn-, or post-impact, we used a data synthesis approach, utilizing High Resolution Imaging Science Experiment (HiRISE), Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), Context Camera (CTX), and Thermal Emission Imaging System (THEMIS) imagery. Opaline silica is observed in two locations on the southwestern side of the uplift and is interpreted to have been pre-existing or formed via hydrothermal alteration due to stratigraphic relationships with the overlying impact melt unit. Both Fe/Mg smectite and low-calcium pyroxene (LCP) are found throughout the uplift. Bedrock exposures on the northern wall of Coprates Chasma containing Fe/Mg smectite and LCP suggest an uplifted origin for these units. In all cases, although a pre-existing origin is probable, it is difficult to rule out the possibility of an impact-generated hydrothermal origin. Using the observed stratigraphy exposed in Coprates Chasma and bedrock exposures analyzed in nearby craters, we were able to constrain the pre-impact stratigraphy around Elorza. The near-subsurface consists of Hesperian-aged, discontinuous lava/ash deposits that may be interposed with opaline silica-bearing deposits, overlying Noachian basement consisting of smectite-bearing bedrock and LCP- bearing light-toned fractured bedrock.

Classification of java tea (Orthosiphon aristatus) quality using FTIR spectroscopy and chemometrics

NASA Astrophysics Data System (ADS)

Heryanto, R.; Pradono, D. I.; Marlina, E.; Darusman, L. K.

2017-05-01

Java tea (Orthosiphon aristatus) is a plant that widely used as a medicinal herb in Indonesia. Its quality is varying depends on various factors, such as cultivating area, climate and harvesting time. This study aimed to investigate the effectiveness of FTIR spectroscopy coupled with chemometrics for discriminating the quality of java tea from different cultivating area. FTIR spectra of ethanolic extracts were collected from five different regions of origin of java tea. Prior to chemometrics evaluation, spectra were pre-processed by using baselining, normalization and derivatization. Principal Components Analysis (PCA) was used to reduce the spectra to two PCs, which explained 73% of the total variance. Score plot of two PCs showed groupings of the samples according to their regions of origin. Furthermore, Partial Least Squares-Discriminant Analysis (PLSDA) was applied to the pre-processed data. The approach produced an external validation success rate of 100%. This study shows that FTIR analysis and chemometrics has discriminatory power to classify java tea based on its quality related to the region of origin.

A Historical Taxonomy of Origin of Species Problems and Its Relevance to the Historiography of Evolutionary Thought.

PubMed

Tanghe, Koen B

2017-11-01

Historians tend to speak of the problem of the origin of species or the species question, as if it were a monolithic problem. In reality, the phrase (or similar variants) refers to a, historically, surprisingly fluid and pluriform scientific issue. It has, in the course of the past five centuries, been used in no less than ten different ways or contexts. A clear taxonomy of these separate problems is useful or relevant in two ways. It certainly helps to disentangle confusions that have inevitably emerged in the literature in its absence. It may, secondly, also help us to gain a more thorough understanding, or sharper view, of the (pre)history of evolutionary thought. A consequent problem-centric look at that (pre)history through the lens of various origin of species problems certainly yields intriguing results, including and particularly for our understanding of the genesis of the Wallace-Darwin theory of evolution through natural selection.

A new method suitable for calculating accurately wetting temperature over a wide range of conditions: Based on the adaptation of continuation algorithm to classical DFT

NASA Astrophysics Data System (ADS)

Zhou, Shiqi

2017-11-01

A new scheme is put forward to determine the wetting temperature (Tw) by utilizing the adaptation of arc-length continuation algorithm to classical density functional theory (DFT) used originally by Frink and Salinger, and its advantages are summarized into four points: (i) the new scheme is applicable whether the wetting occurs near a planar or a non-planar surface, whereas a zero contact angle method is considered only applicable to a perfectly flat solid surface, as demonstrated previously and in this work, and essentially not fit for non-planar surface. (ii) The new scheme is devoid of an uncertainty, which plagues a pre-wetting extrapolation method and originates from an unattainability of the infinitely thick film in the theoretical calculation. (iii) The new scheme can be similarly and easily applied to extreme instances characterized by lower temperatures and/or higher surface attraction force field, which, however, can not be dealt with by the pre-wetting extrapolation method because of the pre-wetting transition being mixed with many layering transitions and the difficulty in differentiating varieties of the surface phase transitions. (iv) The new scheme still works in instance wherein the wetting transition occurs close to the bulk critical temperature; however, this case completely can not be managed by the pre-wetting extrapolation method because near the bulk critical temperature the pre-wetting region is extremely narrow, and no enough pre-wetting data are available for use of the extrapolation procedure.

Pre-dispersal predation effect on seed packaging strategies and seed viability.

PubMed

DeSoto, Lucía; Tutor, David; Torices, Rubén; Rodríguez-Echeverría, Susana; Nabais, Cristina

2016-01-01

An increased understanding of intraspecific seed packaging (i.e. seed size/number strategy) variation across different environments may improve current knowledge of the ecological forces that drive seed evolution in plants. In particular, pre-dispersal seed predation may influence seed packaging strategies, triggering a reduction of the resources allocated to undamaged seeds within the preyed fruits. Assessing plant reactions to pre-dispersal seed predation is crucial to a better understanding of predation effects, but the response of plants to arthropod attacks remains unexplored. We have assessed the effect of cone predation on the size and viability of undamaged seeds in populations of Juniperus thurifera with contrasting seed packaging strategies, namely, North African populations with single-large-seeded cones and South European populations with multi-small-seeded cones. Our results show that the incidence of predation was lower on the single-large-seeded African cones than on the multi-small-seeded European ones. Seeds from non-preyed cones were also larger and had a higher germination success than uneaten seeds from preyed cones, but only in populations with multi-seeded cones and in cones attacked by Trisetacus sp., suggesting a differential plastic response to predation. It is possible that pre-dispersal seed predation has been a strong selective pressure in European populations with high cone predation rates, being a process which maintains multi-small-seeded cones and empty seeds as a strategy to save some seeds from predation. Conversely, pre-dispersal predation might not have a strong effect in the African populations with single-large-seeded cones characterized by seed germination and filling rates higher than those in the European populations. Our results indicate that differences in pre-dispersal seed predators and predation levels may affect both selection on and intraspecific variation in seed packaging.

The first whole transcriptomic exploration of pre-oviposited early chicken embryos using single and bulked embryonic RNA-sequencing.

PubMed

Hwang, Young Sun; Seo, Minseok; Choi, Hee Jung; Kim, Sang Kyung; Kim, Heebal; Han, Jae Yong

2018-04-01

The chicken is a valuable model organism, especially in evolutionary and embryology research because its embryonic development occurs in the egg. However, despite its scientific importance, no transcriptome data have been generated for deciphering the early developmental stages of the chicken because of practical and technical constraints in accessing pre-oviposited embryos. Here, we determine the entire transcriptome of pre-oviposited avian embryos, including oocyte, zygote, and intrauterine embryos from Eyal-giladi and Kochav stage I (EGK.I) to EGK.X collected using a noninvasive approach for the first time. We also compare RNA-sequencing data obtained using a bulked embryo sequencing and single embryo/cell sequencing technique. The raw sequencing data were preprocessed with two genome builds, Galgal4 and Galgal5, and the expression of 17,108 and 26,102 genes was quantified in the respective builds. There were some differences between the two techniques, as well as between the two genome builds, and these were affected by the emergence of long intergenic noncoding RNA annotations. The first transcriptome datasets of pre-oviposited early chicken embryos based on bulked and single embryo sequencing techniques will serve as a valuable resource for investigating early avian embryogenesis, for comparative studies among vertebrates, and for novel gene annotation in the chicken genome.

Genomic mapping of single-stranded DNA in hydroxyurea-challenged yeasts identifies origins of replication.

PubMed

Feng, Wenyi; Collingwood, David; Boeck, Max E; Fox, Lindsay A; Alvino, Gina M; Fangman, Walton L; Raghuraman, Mosur K; Brewer, Bonita J

2006-02-01

During DNA replication one or both strands transiently become single stranded: first at the sites where initiation of DNA synthesis occurs (known as origins of replication) and subsequently on the lagging strands of replication forks as discontinuous Okazaki fragments are generated. We report a genome-wide analysis of single-stranded DNA (ssDNA) formation in the presence of hydroxyurea during DNA replication in wild-type and checkpoint-deficient rad53 Saccharomyces cerevisiae cells. In wild-type cells, ssDNA was first observed at a subset of replication origins and later 'migrated' bi-directionally, suggesting that ssDNA formation is associated with continuously moving replication forks. In rad53 cells, ssDNA was observed at virtually every known origin, but remained there over time, suggesting that replication forks stall. Telomeric regions seemed to be particularly sensitive to the loss of Rad53 checkpoint function. Replication origins in Schizosaccharomyces pombe were also mapped using our method.

Lung transplantation in idiopathic pulmonary fibrosis: a systematic review of the literature

PubMed Central

2014-01-01

Background Idiopathic pulmonary fibrosis (IPF) is a distinct form of interstitial pneumonia with unknown origin and poor prognosis. Current pharmacologic treatments are limited and lung transplantation is a viable option for appropriate patients. The aim of this review was to summarize lung transplantation survival in IPF patients overall, between single (SLT) vs. bilateral lung transplantation (BLT), pre- and post Lung Allocation Score (LAS), and summarize wait-list survival. Methods A systematic review of English-language studies published in Medline or Embase between 1990 and 2013 was performed. Eligible studies were those of observational design reporting survival post-lung transplantation or while on the wait list among IPF patients. Results Median survival post-transplantation among IPF patients is estimated at 4.5 years. From ISHLT and OPTN data, one year survival ranged from 75% - 81%; 3-year: 59% - 64%; and 5-year: 47% - 53%. Post-transplant survival is lower for IPF vs. other underlying pre-transplant diagnoses. The proportion of IPF patients receiving BLT has steadily increased over the last decade and a half. Unadjusted analyses suggest improved long-term survival for BLT vs. SLT; after adjustment for patient characteristics, the differences tend to disappear. IPF patients account for the largest proportion of patients on the wait list and while wait list time has decreased, the number of transplants for IPF patients has increased over time. OPTN data show that wait list mortality is higher for IPF patients vs. other diagnoses. The proportion of IPF patients who died while awaiting transplantation ranged from 14% to 67%. While later transplant year was associated with increased survival, no significant differences were noted pre vs. post LAS implementation; however a high LAS vs low LAS was associated with decreased one-year survival. Conclusions IPF accounts for the largest proportion of patients awaiting lung transplants, and IPF is associated with higher wait-list and post-transplant mortality vs. other diagnoses. Improved BLT vs. SLT survival may be the result of selection bias. Survival pre- vs. post LAS appears to be similar except for IPF patients with high LAS, who have lower survival compared to pre-LAS. Data on post-transplant morbidity outcomes are sparse. PMID:25127540

Anchoring durum wheat diversity in the reality of traditional agricultural systems: varieties, seed management, and farmers’ perception in two Moroccan regions

PubMed Central

2014-01-01

Background Traditional agrosystems are the places were crop species have evolved and continue to evolve under a combination of human and environmental pressures. A better knowledge of the mechanisms underlying the dynamics of crop diversity in these agrosystems is crucial to sustain food security and farmers’ self-reliance. It requires as a first step, anchoring a description of the available diversity in its geographical, environmental, cultural and socio-economic context. Methods We conducted interviews with farmers cultivating durum wheat in two contrasted traditional agrosystems of Morocco in the Pre-Rif (163 farmers) and in the oases of the Atlas Mountains (110 farmers). We documented the varietal diversity of durum wheat, the main characteristics of the farms, the farming and seed management practices applied to durum wheat, and the farmers’ perception of their varieties. Results As expected in traditional agrosystems, farmers largely practiced diversified subsistence agriculture on small plots and relied on on-farm seed production or informal seed exchange networks. Heterogeneity nevertheless prevailed on many variables, especially on the modernization of practices in the Pre-Rif region. Fourteen (resp. 11) traditional and 5 (resp. 3) modern varieties were identified in the Pre-Rif region (resp. in the Atlas Mountains). The majority of farmers grew a single variety, and most traditional varieties were distributed in restricted geographical areas. At the farm level, more than half of the varieties were renewed in the last decade in the Pre-Rif, a more rapid renewal than in the Atlas Mountain. Modern varieties were more prevalent in the Pre-Rif region and were integrated in the traditional practices of seed production, selection and exchange. They were clearly distinguished by the farmers from the landraces, the last ones being appreciated for their quality traits. Conclusions The surveyed traditional agrosystems constitute open, dynamic and heterogeneous entities. We suggest that competing factors could favour or limit the cultivation of improved varieties and the erosion of original durum wheat diversity. This first description opens the way to focused further investigations, including complementing variety names with cultural, genetic and phenotypic information and unravelling the multidimensional factors and consequences of modern variety adoption. PMID:25027694

The Single Period Inventory Model: Origins, Solutions, Variations, and Applications.

DTIC Science & Technology

1977-09-01

IN OPERATIONS RESEARCH from the NAVAL POSTGRADUATE SCHOOL September 1977 Author Approved by: :c^L*S /y^td^US^C. f. :t.’.".S,. Chairman...Department of Operations Research Dean of Information/and Policy Sciences "•>.’• • . ABSTRACT The classic newspaper boy or single period inventory... Research , expended while assisting me in my thesis effort. I. INTRODUCTION This thesis is devoted to the origins and development of a single

Bi-specific splice-switching PMO oligonucleotides conjugated via a single peptide active in a mouse model of Duchenne muscular dystrophy

PubMed Central

Shabanpoor, Fazel; McClorey, Graham; Saleh, Amer F.; Järver, Peter; Wood, Matthew J.A.; Gait, Michael J.

2015-01-01

The potential for therapeutic application of splice-switching oligonucleotides (SSOs) to modulate pre-mRNA splicing is increasingly evident in a number of diseases. However, the primary drawback of this approach is poor cell and in vivo oligonucleotide uptake efficacy. Biological activities can be significantly enhanced through the use of synthetically conjugated cationic cell penetrating peptides (CPPs). Studies to date have focused on the delivery of a single SSO conjugated to a CPP, but here we describe the conjugation of two phosphorodiamidate morpholino oligonucleotide (PMO) SSOs to a single CPP for simultaneous delivery and pre-mRNA targeting of two separate genes, exon 23 of the Dmd gene and exon 5 of the Acvr2b gene, in a mouse model of Duchenne muscular dystrophy. Conjugations of PMOs to a single CPP were carried out through an amide bond in one case and through a triazole linkage (‘click chemistry’) in the other. The most active bi-specific CPP–PMOs demonstrated comparable exon skipping levels for both pre-mRNA targets when compared to individual CPP–PMO conjugates both in cell culture and in vivo in the mdx mouse model. Thus, two SSOs with different target sequences conjugated to a single CPP are biologically effective and potentially suitable for future therapeutic exploitation. PMID:25468897

Effects of menarcheal age on the anterior cruciate ligament injury risk factors during single-legged drop landing in female artistic elite gymnasts.

PubMed

Kim, Kew-Wan; Lim, Bee-Oh

2014-11-01

Although numerous studies have demonstrated the relationship between maturation and lower extremity biomechanics during landing in team sport athletes, we are presently uninformed of any research that examined the single-legged drop landing biomechanics of gymnasts. The purpose of this study is to investigate the effects of the menarcheal age on the lower extremity biomechanics during a single-legged drop landing in female artistic elite gymnasts. Twenty-two female artistic elite gymnasts, between 9 and 36 years of age, participated in this study. The participants were divided into two groups pre- (n = 11) and post- (n = 11) menarche and asked to perform a single-legged drop landing on top of a 30 cm platform and land on a force plate. The statistical analysis consisted of the multivariate analysis with the level of significance set at p < 0.05. The post-menarche group showed a decrease in their maximum knee flexion angle and increase in their maximum knee abduction angle, maximum internal tibial rotation angle, maximum knee abduction moment, and hamstring-quadriceps muscle activity ratio compared with the pre-menarche group during the single-legged drop landing. The post-menarche group showed an increased noncontact anterior cruciate ligament injury risk, due to their greater knee loads, compared with the pre-menarche group.

The association between radiographic severity and pre-operative function in patients undergoing primary knee replacement for osteoarthritis.

PubMed

Dowsey, Michelle M; Dieppe, Paul; Lohmander, Stefan; Castle, David; Liew, Danny; Choong, Peter F M

2012-12-01

To determine the association between radiographic osteoarthritis (OA) and pre-operative function in patients undergoing primary knee replacement. Single centre study examining pre-operative outcomes in a consecutive series of 525 patients who underwent primary knee replacement for OA between January 2006 and December 2007. Pre-operative data included: demographics, American Society of Anaesthesiologists (ASA) status and OA in the contralateral knee. The International Knee Society (IKS) rating and Short Form-12 (SF-12) were recorded for each patient. Pre-operative radiographs were read by a single observer for Kellgren and Lawrence (K&L) grading and Osteoarthritis Research Society International (OARSI) atlas features. Multiple linear regression was used to assess the strength of associations between radiographic OA severity and function, adjusting for clinically relevant variables. Lateral tibiofemoral osteophyte grade was an independent predictor of pre-operative function as determined by the functional sub-scale of the IKS in patients undergoing primary knee replacement (coefficient=2.58, p=0.033). No associations were evident between pre-operative function and modified K&L, joint space narrowing, Ahlbäck attrition and coronal plane deformity. Other statistically significant predictors of poorer pre-operative function included: advancing age, female gender, knee pain and poorer SF-12 mental component summary scores which including osteophyte grade accounted for 24.6% of the variation in functional scores, (r=0.496). Osteophytes in the lateral compartment of the knee were associated with pre-operative function in patients with advanced knee OA. Further studies are required which examine individual radiographic features specifically in patients with advanced knee OA to determine their relationship to pre-operative pain and function. Copyright © 2012 Elsevier B.V. All rights reserved.

The Effect of Special Teaching Methods Class on the Level of Teachers' Self-Efficacy Perception of Pre-Service Teacher

ERIC Educational Resources Information Center

Gökdag Baltaoglu, Meltem

2015-01-01

The purpose of this study is to evaluate the change in the level of teachers' self-efficacy perception of primary school Social Studies pre-service teachers who take the special teaching methods class. Single group pretest-posttest model from pre-experimental patterns was applied in the research. The study group of the research consisted of 59…

Single-cell RNA sequencing highlights transcription activity of autophagy-related genes during hematopoietic stem cell formation in mouse embryos.

PubMed

Hu, Yongfei; Huang, Yan; Yi, Ying; Wang, Hongwei; Liu, Bing; Yu, Jia; Wang, Dong

2017-04-03

Accumulating evidence has demonstrated that macroautophagy/autophagy plays an essential role in self-renewal and differentiation in embryonic hematopoiesis. Here, according to the RNA sequencing data sets of 5 population cells related to hematopoietic stem cell (HSC) formation during mouse embryogenesis (endothelial cells, PTPRC/CD45 - and PTPRC/CD45 + pre-HSCs in the E11 aorta-gonad-mesonephros (AGM) region, mature HSCs in E12 and E14 fetal liver), we explored the dynamic expression of mouse autophagy-related genes in this course at the single-cell level. Our results revealed that the transcription activity of autophagy-related genes had a substantial increase when endothelial cells (ECs) specified into pre-HSCs, and the upregulation of autophagy-essential genes correlated with reduced NOTCH signaling in pre-HSCs, suggesting the autophagy activity may be greatly enhanced during pre-HSC specification from endothelial precursors. In summary, our results presented strong evidence that autophagy plays a critical role in HSC emergence during mouse midgestation.

Improved ICU design reduces acquisition of antibiotic-resistant bacteria: a quasi-experimental observational study

PubMed Central

2011-01-01

Introduction The role of ICU design and particularly single-patient rooms in decreasing bacterial transmission between ICU patients has been debated. A recent change in our ICU allowed further investigation. Methods Pre-move ICU-A and pre-move ICU-B were open-plan units. In March 2007, ICU-A moved to single-patient rooms (post-move ICU-A). ICU-B remained unchanged (post-move ICU-B). The same physicians cover both ICUs. Cultures of specified resistant organisms in surveillance or clinical cultures from consecutive patients staying >48 hours were compared for the different ICUs and periods to assess the effect of ICU design on acquisition of resistant organisms. Results Data were collected for 62, 62, 44 and 39 patients from pre-move ICU-A, post-move ICU-A, pre-move ICU-B and post-move ICU-B, respectively. Fewer post-move ICU-A patients acquired resistant organisms (3/62, 5%) compared with post-move ICU-B patients (7/39, 18%; P = 0.043, P = 0.011 using survival analysis) or pre-move ICU-A patients (14/62, 23%; P = 0.004, P = 0.012 on survival analysis). Only the admission period was significant for acquisition of resistant organisms comparing pre-move ICU-A with post-move ICU-A (hazard ratio = 5.18, 95% confidence interval = 1.03 to 16.06; P = 0.025). More antibiotic-free days were recorded in post-move ICU-A (median = 3, interquartile range = 0 to 5) versus post-move ICU-B (median = 0, interquartile range = 0 to 4; P = 0.070) or pre-move ICU-A (median = 0, interquartile range = 0 to 4; P = 0.017). Adequate hand hygiene was observed on 140/242 (58%) occasions in post-move ICU-A versus 23/66 (35%) occasions in post-move ICU-B (P < 0.001). Conclusions Improved ICU design, and particularly use of single-patient rooms, decreases acquisition of resistant bacteria and antibiotic use. This observation should be considered in future ICU design. PMID:21914222

Improved ICU design reduces acquisition of antibiotic-resistant bacteria: a quasi-experimental observational study.

PubMed

Levin, Phillip D; Golovanevski, Mila; Moses, Allon E; Sprung, Charles L; Benenson, Shmuel

2011-01-01

The role of ICU design and particularly single-patient rooms in decreasing bacterial transmission between ICU patients has been debated. A recent change in our ICU allowed further investigation. Pre-move ICU-A and pre-move ICU-B were open-plan units. In March 2007, ICU-A moved to single-patient rooms (post-move ICU-A). ICU-B remained unchanged (post-move ICU-B). The same physicians cover both ICUs. Cultures of specified resistant organisms in surveillance or clinical cultures from consecutive patients staying >48 hours were compared for the different ICUs and periods to assess the effect of ICU design on acquisition of resistant organisms. Data were collected for 62, 62, 44 and 39 patients from pre-move ICU-A, post-move ICU-A, pre-move ICU-B and post-move ICU-B, respectively. Fewer post-move ICU-A patients acquired resistant organisms (3/62, 5%) compared with post-move ICU-B patients (7/39, 18%; P = 0.043, P = 0.011 using survival analysis) or pre-move ICU-A patients (14/62, 23%; P = 0.004, P = 0.012 on survival analysis). Only the admission period was significant for acquisition of resistant organisms comparing pre-move ICU-A with post-move ICU-A (hazard ratio = 5.18, 95% confidence interval = 1.03 to 16.06; P = 0.025). More antibiotic-free days were recorded in post-move ICU-A (median = 3, interquartile range = 0 to 5) versus post-move ICU-B (median = 0, interquartile range = 0 to 4; P = 0.070) or pre-move ICU-A (median = 0, interquartile range = 0 to 4; P = 0.017). Adequate hand hygiene was observed on 140/242 (58%) occasions in post-move ICU-A versus 23/66 (35%) occasions in post-move ICU-B (P < 0.001). Improved ICU design, and particularly use of single-patient rooms, decreases acquisition of resistant bacteria and antibiotic use. This observation should be considered in future ICU design.

Event-related brain potentials, bilateral electrodermal activity and Mangina-Test performance in learning disabled/ADHD pre-adolescents with severe behavioral disorders as compared to age-matched normal controls.

PubMed

Mangina, C A; Beuzeron-Mangina, J H; Grizenko, N

2000-07-01

The most frequently encountered developmental problems of learning disabilities/ADHD often co-exist with severe behavioral disorders. As a direct consequence, this condition opens the way to delinquency, school drop-out, depression, suicide, substance abuse, work absenteeism, and other psycho-social complications. In this paper, we are presenting a selective overview of our previous research and its clinical applications in this field as it relates to our present research data pertaining to the effects of our original Memory Workload Paradigm on the event-related brain potentials in differentiating normal and pathological pre-adolescents (learning disabled/ADHD with concomitant severe behavioral disorders such as oppositional and conduct). In addition, it provides data on the bilateral electrodermal activity during cognitive workload and Mangina-Test performance of pathological and normal pre-adolescents conducted in separate sessions. The results of our present research indicate that a significant memory load effect for the P450 latency (F(3,27)=4.98, P<0.01) and the P450 amplitude (F(3,27)=3.57, P<0.05) was present for normal pre-adolescents which was absent in pathological pre-adolescents. Moreover, enhanced N450 ERP amplitudes to our Memory Workload Paradigm in pre-frontal and frontal regions clearly differentiated normal from pathological pre-adolescents (F(1, 18)=12.21, P<0.004). Furthermore, significant differences between normal and pathological groups were found in bilateral electrodermal activity (F(1,18)=23.86, P<0.001) and on the Mangina-Test performance (F(1,18)=75.35, P<0.001). Our present research findings provide an original and valuable demonstration of an integrative and effective clinical psychophysiological application of central (ERPs), autonomic (bilateral electrodermal activity) and neuro-psychometric aspects (Mangina-Test) which characterize normal and pathological pre-adolescents and underpin the neurophysiological basis of learning disabled/ADHD with severe behavioral disorders as opposed to normal subjects.

A genome wide association study for backfat thickness in Italian Large White pigs highlights new regions affecting fat deposition including neuronal genes

PubMed Central

2012-01-01

Background Carcass fatness is an important trait in most pig breeding programs. Following market requests, breeding plans for fresh pork consumption are usually designed to reduce carcass fat content and increase lean meat deposition. However, the Italian pig industry is mainly devoted to the production of Protected Designation of Origin dry cured hams: pigs are slaughtered at around 160 kg of live weight and the breeding goal aims at maintaining fat coverage, measured as backfat thickness to avoid excessive desiccation of the hams. This objective has shaped the genetic pool of Italian heavy pig breeds for a few decades. In this study we applied a selective genotyping approach within a population of ~ 12,000 performance tested Italian Large White pigs. Within this population, we selectively genotyped 304 pigs with extreme and divergent backfat thickness estimated breeding value by the Illumina PorcineSNP60 BeadChip and performed a genome wide association study to identify loci associated to this trait. Results We identified 4 single nucleotide polymorphisms with P≤5.0E-07 and additional 119 ones with 5.0E-07

The effect of dyad versus individual simulation-based ultrasound training on skills transfer.

PubMed

Tolsgaard, Martin G; Madsen, Mette E; Ringsted, Charlotte; Oxlund, Birgitte S; Oldenburg, Anna; Sorensen, Jette L; Ottesen, Bent; Tabor, Ann

2015-03-01

Dyad practice may be as effective as individual practice during clinical skills training, improve students' confidence, and reduce costs of training. However, there is little evidence that dyad training is non-inferior to single-student practice in terms of skills transfer. This study was conducted to compare the effectiveness of simulation-based ultrasound training in pairs (dyad practice) with that of training alone (single-student practice) on skills transfer. In a non-inferiority trial, 30 ultrasound novices were randomised to dyad (n = 16) or single-student (n = 14) practice. All participants completed a 2-hour training programme on a transvaginal ultrasound simulator. Participants in the dyad group practised together and took turns as the active practitioner, whereas participants in the single group practised alone. Performance improvements were evaluated through pre-, post- and transfer tests. The transfer test involved the assessment of a transvaginal ultrasound scan by one of two clinicians using the Objective Structured Assessment of Ultrasound Skills (OSAUS). Thirty participants completed the simulation-based training and 24 of these completed the transfer test. Dyad training was found to be non-inferior to single-student training: transfer test OSAUS scores were significantly higher than the pre-specified non-inferiority margin (delta score 7.8%, 95% confidence interval -3.8-19.6%; p = 0.04). More dyad (71.4%) than single (30.0%) trainees achieved OSAUS scores above a pre-established pass/fail level in the transfer test (p = 0.05). There were significant differences in performance scores before and after training in both groups (pre- versus post-test, p < 0.01) with large effect sizes (Cohen's d = 3.85) and no significant interactions between training type and performance (p = 0.59). The dyad group demonstrated higher training efficiency in terms of simulator score per number of attempts compared with the single-student group (p = 0.03). Dyad practice improves the efficiency of simulation-based training and is non-inferior to individual practice in terms of skills transfer. © 2015 John Wiley & Sons Ltd.

A comparison of the original Rappaport medium (R medium) and the Rappaport-Vassiliadis medium (RV medium) in the isolation of salmonellae from meat products.

PubMed Central

Vassiliadis, P.; Kalapothaki, V.; Mavrommati, C.; Trichopoulos, D.

1984-01-01

The Rappaport-Vassiliadis enrichment medium (RV medium) in 10 ml quantities (RV/43 degrees C, 10 ml) inoculated with 0.1 ml of pre-enrichment medium (P medium) was found more efficient in the isolation of salmonellae from 409 pre-enriched samples (mainly meat products), than the original Rappaport medium incubated at 43 degrees C (R/43 degrees C) and the RV medium in 5 ml quantities (RV/43 degrees C, 5 ml) inoculated with 0.01 ml of P medium (P less than 0.001, in both instances). Therefore, the inoculum from pre-enriched foods should not be less than 0.1 ml in 10 ml of RV medium. The RV/43 degrees, 10 ml was also better (P less than 0.01) in detecting samples containing salmonellas than the original Rappaport medium incubated at 37 degrees C (R/37 degrees C, 10 ml) and the modification R25 of R medium incubated at 37 degrees C. The R25 modification was used in 10 ml quantities (R25/37 degrees C, 10 ml) inoculated with 0.1 ml of P medium and in 5 ml quantities (R25/37 degrees, 5 ml) inoculated with 0.01 ml of P medium. The last two R25 procedures were of the same efficiency in isolating salmonellas from meat products. PMID:6747286

Origin of malaria cases: a 7-year audit of global trends in indigenous and imported cases in relation to malaria elimination.

PubMed

Velarde-Rodríguez, Mar; Van den Bergh, Rafael; Fergus, Cristin; Casellas, Aina; Sanz, Sergi; Cibulskis, Richard; Ramsay, Andrew R; Bissell, Karen; Zachariah, Rony

2015-01-01

Countries in the different stages of pre-elimination, elimination, and prevention of reintroduction are required to report the number of indigenous and imported malaria cases to the World Health Organization (WHO). However, these data have not been systematically analysed at the global level. For the period 2007 to 2013, we aimed to report on 1) the proportion of countries providing data on the origin of malaria cases and 2) the origin of malaria cases in countries classified as being in the stages of pre-elimination, elimination and prevention of reintroduction. An observational study using annual data reported through routine health information systems to the WHO Global Malaria Programme between 2007 and 2013. For all countries classified as being in pre-elimination, elimination, and prevention of reintroduction in the year 2013, there has been a substantial decrease in the total number of indigenous malaria cases, from more than 15,000 cases reported in 2007 to less than 4,000 cases reported in 2013. However, the total number of imported malaria cases has increased over that time period, from 5,600 imported cases in 2007 to approximately 6,800 in 2013. Vigilant monitoring of the numbers of imported and indigenous malaria cases at national and global levels as well as appropriate strategies to target these cases will be critical to achieve malaria eradication.

Technical innovation: Intragastric Single Port Sleeve Gastrectomy (IGSG). A feasibility survival study on porcine model.

PubMed

Estupinam, Oscar; Oliveira, André Lacerda de Abreu; Antunes, Fernanda; Galvão, Manoel; Phillips, Henrique; Scheffer, Jussara Peters; Rios, Marcelo; Zorron, Ricardo

2018-01-01

To perform technically the laparoscopic sleeve gastrectomy (LSG) using a unique Intragastric Single Port (IGSG) in animal swine model, evidencing an effective and safe procedure, optimizing the conventional technique. IGSG was performed in 4 minipigs, using a percutaneous intragastric single port located in the pre-pyloric region. The gastric stapling of the greater curvature started from the pre-pyloric region towards the angle of His by Endo GIA™ system and the specimen was removed through the single port. In the postoperative day 30, the animals were sacrificed and submitted to autopsy. All procedures were performed without conversion, and all survived 30 days. The mean operative time was 42 min. During the perioperative period no complications were observed during invagination and stapling. No postoperative complications occurred. Post-mortem examination showed no leaks or infectious complications. Intragastric Single Port is a feasible procedure that may be a suitable alternative technique of sleeve gastrectomy for the treatment of morbid obesity.

Quantitative Connection between Ensemble Thermodynamics and Single-Molecule Kinetics: A Case Study Using Cryogenic Electron Microscopy and Single-Molecule Fluorescence Resonance Energy Transfer Investigations of the Ribosome.

PubMed

Thompson, Colin D Kinz; Sharma, Ajeet K; Frank, Joachim; Gonzalez, Ruben L; Chowdhury, Debashish

2015-08-27

At equilibrium, thermodynamic and kinetic information can be extracted from biomolecular energy landscapes by many techniques. However, while static, ensemble techniques yield thermodynamic data, often only dynamic, single-molecule techniques can yield the kinetic data that describe transition-state energy barriers. Here we present a generalized framework based upon dwell-time distributions that can be used to connect such static, ensemble techniques with dynamic, single-molecule techniques, and thus characterize energy landscapes to greater resolutions. We demonstrate the utility of this framework by applying it to cryogenic electron microscopy (cryo-EM) and single-molecule fluorescence resonance energy transfer (smFRET) studies of the bacterial ribosomal pre-translocation complex. Among other benefits, application of this framework to these data explains why two transient, intermediate conformations of the pre-translocation complex, which are observed in a cryo-EM study, may not be observed in several smFRET studies.

General Model Study of Scour at Proposed Pier Extensions - Santa Ana River at BNSF Bridge, Corona, California

DTIC Science & Technology

2017-11-01

model of the bridge piers, other related structures, and the adjacent channel. Data from the model provided a qualitative and quantitative evaluation of...minus post-test lidar survey . ......................... 42 Figure 38. Test 1 (30,000 cfs existing conditions) pre- minus post-test lidar survey ...43 Figure 39. Test 7 (15,000 cfs original proposed conditions) pre- minus post-test lidar survey

Weak Value Amplification of a Post-Selected Single Photon

NASA Astrophysics Data System (ADS)

Hallaji, Matin

Weak value amplification (WVA) is a measurement technique in which the effect of a pre- and post-selected system on a weakly interacting probe is magnified. In this thesis, I present the first experimental observation of WVA of a single photon. We observed that a signal photon --- sent through a polarization interferometer and post-selected by photodetection in the almost-dark port --- can act like eight photons. The effect of this single photon is measured as a nonlinear phase shift on a separate laser beam. The interaction between the two is mediated by a sample of laser- cooled 85Rb atoms. Electromagnetically induced transparency (EIT) is used to enhance the nonlinearity and overcome resonant absorption. I believe this work to be the first demonstration of WVA where a deterministic interaction is used to entangle two distinct optical systems. In WVA, the amplification is contingent on discarding a large portion of the original data set. While amplification increases measurement sensitivity, discarding data worsens it. Questioning whether these competing effects conspire to improve or diminish measurement accuracy has resulted recently in controversy. I address this question by calculating the maximum amount of information achievable with the WVA technique. By comparing this information to that achievable by the standard technique, where no post-selection is employed, I show that the WVA technique can be advantageous under a certain class of noise models. Finally, I propose a way to optimally apply the WVA technique.

Bar code-based pre-transfusion check in pre-operative autologous blood donation.

PubMed

Ohsaka, Akimichi; Furuta, Yoshiaki; Ohsawa, Toshiya; Kobayashi, Mitsue; Abe, Katsumi; Inada, Eiichi

2010-10-01

The objective of this study was to demonstrate the feasibility of a bar code-based identification system for the pre-transfusion check at the bedside in the setting of pre-operative autologous blood donation (PABD). Between July 2003 and December 2008 we determined the compliance rate and causes of failure of electronic bedside checking for PABD transfusion. A total of 5627 (9% of all transfusions) PABD units were administered without a single mistransfusion. The overall rate of compliance with electronic checking was 99%. The bar code-based identification system was applicable to the pre-transfusion check for PABD transfusion. Copyright © 2010 Elsevier Ltd. All rights reserved.

Heterologous Prime-Boost HIV-1 Vaccination Regimens in Pre-Clinical and Clinical Trials

PubMed Central

Brown, Scott A.; Surman, Sherri L.; Sealy, Robert; Jones, Bart G.; Slobod, Karen S.; Branum, Kristen; Lockey, Timothy D.; Howlett, Nanna; Freiden, Pamela; Flynn, Patricia; Hurwitz, Julia L.

2010-01-01

Currently, there are more than 30 million people infected with HIV-1 and thousands more are infected each day. Vaccination is the single most effective mechanism for prevention of viral disease, and after more than 25 years of research, one vaccine has shown somewhat encouraging results in an advanced clinical efficacy trial. A modified intent-to-treat analysis of trial results showed that infection was approximately 30% lower in the vaccine group compared to the placebo group. The vaccine was administered using a heterologous prime-boost regimen in which both target antigens and delivery vehicles were changed during the course of inoculations. Here we examine the complexity of heterologous prime-boost immunizations. We show that the use of different delivery vehicles in prime and boost inoculations can help to avert the inhibitory effects caused by vector-specific immune responses. We also show that the introduction of new antigens into boost inoculations can be advantageous, demonstrating that the effect of ‘original antigenic sin’ is not absolute. Pre-clinical and clinical studies are reviewed, including our own work with a three-vector vaccination regimen using recombinant DNA, virus (Sendai virus or vaccinia virus) and protein. Promising preliminary results suggest that the heterologous prime-boost strategy may possibly provide a foundation for the future prevention of HIV-1 infections in humans. PMID:20407589

Pre-Study Walkthrough with a Commercial Pilot for a Preliminary Single Pilot Operations Experiment

NASA Technical Reports Server (NTRS)

O'Connor-Dreher, Ryan; Roberts, Z.; Ziccardi, J.; Vu, K-P. L.; Strybel, T.; Koteskey, Robert William; Lachter, Joel B.; Vi Dao, Quang; Johnson, Walter W.; Battiste, V.

2013-01-01

The number of crew members in commercial flights has decreased to two members, down from the five-member crew required 50 years ago. One question of interest is whether the crew should be reduced to one pilot. In order to determine the critical factors involved in safely transitioning to a single pilot, research must examine whether any performance deficits arise with the loss of a crew member. With a concrete understanding of the cognitive and behavioral role of a co-pilot, aeronautical technologies and procedures can be developed that make up for the removal of the second aircrew member. The current project describes a pre-study walkthrough process that can be used to help in the development of scenarios for testing future concepts and technologies for single pilot operations. Qualitative information regarding the tasks performed by the pilots can be extracted with this technique and adapted for future investigations of single pilot operations.

Growth Asymmetry, Head Circumference, and Neurodevelopmental Outcomes in Infants with Single Ventricles.

PubMed

Miller, Thomas A; Zak, Victor; Shrader, Peter; Ravishankar, Chitra; Pemberton, Victoria L; Newburger, Jane W; Shillingford, Amanda J; Dagincourt, Nicholas; Cnota, James F; Lambert, Linda M; Sananes, Renee; Richmond, Marc E; Hsu, Daphne T; Miller, Stephen G; Zyblewski, Sinai C; Williams, Richard V

2016-01-01

To assess the variability in asymmetric growth and its association with neurodevelopment in infants with single ventricle (SV). We analyzed weight-for-age z-score minus head circumference-for-age z-score (HCAZ), relative head growth (cm/kg), along with individual growth variables in subjects prospectively enrolled in the Infant Single Ventricle Trial. Associations between growth indices and scores on the Psychomotor Developmental Index (PDI) and Mental Developmental Index (MDI) of the Bayley Scales of Infant Development-II (BSID-II) at 14 months were assessed. Of the 230 subjects enrolled in the Infant Single Ventricle trial, complete growth data and BSID-II scores were available in 168 (73%). Across the cohort, indices of asymmetric growth varied widely at enrollment and before superior cavopulmonary connection (SCPC) surgery. BSID-II scores were not associated with these asymmetry indices. In bivariate analyses, greater pre-SCPC HCAZ correlated with higher MDI (r = 0.21; P = .006) and PDI (r = 0.38; P < .001) and a greater HCAZ increase from enrollment to pre-SCPC with higher PDI (r = 0.15; P = .049). In multivariable modeling, pre-SCPC HCAZ was an independent predictor of PDI (P = .03), but not MDI. In infants with SV, growth asymmetry was not associated with neurodevelopment at 14 months, but pre-SCPC HCAZ was associated with PDI. Asymmetric growth, important in other high-risk infants, is not a brain-sparing adaptation in infants with SV. Clinicaltrials.gov: NCT00113087. Copyright © 2016 Elsevier Inc. All rights reserved.

Role of the hydrophilic channels of simian virus 40 T-antigen helicase in DNA replication.

PubMed

Wang, Weiping; Manna, David; Simmons, Daniel T

2007-05-01

The simian virus 40 (SV40) hexameric helicase consists of a central channel and six hydrophilic channels located between adjacent large tier domains within each hexamer. To study the function of the hydrophilic channels in SV40 DNA replication, a series of single-point substitutions were introduced at sites not directly involved in protein-protein contacts. The mutants were characterized biochemically in various ways. All mutants oligomerized normally in the absence of DNA. Interestingly, 8 of the 10 mutants failed to unwind an origin-containing DNA fragment and nine of them were totally unable to support SV40 DNA replication in vitro. The mutants fell into four classes based on their biochemical properties. Class A mutants bound DNA normally and had normal ATPase and helicase activities but failed to unwind origin DNA and support SV40 DNA replication. Class B mutants were compromised in single-stranded DNA and origin DNA binding at low protein concentrations. They were defective in helicase activity and unwinding of the origin and in supporting DNA replication. Class C and D mutants possessed higher-than-normal single-stranded DNA binding activity at low protein concentrations. The class C mutants failed to separate origin DNA and support DNA replication. The class D mutants unwound origin DNA normally but were compromised in their ability to support DNA replication. Taken together, these results suggest that the hydrophilic channels have an active role in the unwinding of SV40 DNA from the origin and the placement of the resulting single strands within the helicase.

Tackling Drug Resistant Infection Outbreaks of Global Pandemic Escherichia coli ST131 Using Evolutionary and Epidemiological Genomics

PubMed Central

Downing, Tim

2015-01-01

High-throughput molecular screening is required to investigate the origin and diffusion of antimicrobial resistance in pathogen outbreaks. The most frequent cause of human infection is Escherichia coli, which is dominated by sequence type 131 (ST131)—a set of rapidly radiating pandemic clones. The highly infectious clades of ST131 originated firstly by a mutation enhancing conjugation and adhesion. Secondly, single-nucleotide polymorphisms occurred enabling fluoroquinolone-resistance, which is near-fixed in all ST131. Thirdly, broader resistance through beta-lactamases has been gained and lost frequently, symptomatic of conflicting environmental selective effects. This flexible approach to gene exchange is worrying and supports the proposition that ST131 will develop an even wider range of plasmid and chromosomal elements promoting antimicrobial resistance. To stop ST131, deep genome sequencing is required to understand the origin, evolution and spread of antimicrobial resistance genes. Phylogenetic methods that decipher past events can predict future patterns of virulence and transmission based on genetic signatures of adaptation and gene exchange. Both the effect of partial antimicrobial exposure and cell dormancy caused by variation in gene expression may accelerate the development of resistance. High-throughput sequencing can decode measurable evolution of cell populations within patients associated with systems-wide changes in gene expression during treatments. A multi-faceted approach can enhance assessment of antimicrobial resistance in E. coli ST131 by examining transmission dynamics between hosts to achieve a goal of pre-empting resistance before it emerges by optimising antimicrobial treatment protocols. PMID:27682088

Endodontic flare-ups: comparison of incidence between single and multiple visits procedures in patients attending a Nigerian teaching hospital.

PubMed

Oginni, Ao; Udoye, C I

2004-12-01

The present study was performed to compare the incidence of endodontic flare ups in single with multiple visits treatment procedures, to establish the relationship between pre-operative and post obturation pain in patients attending for endodontic therapy in a Nigerian teaching Hospital. Patients were randomly assigned to either single visit or multiple visits group. Data collected at root canal treatment appointment and recall visits (1st, 7th and 30th day post obturation) include pulp vitality status, the presence or absence of pre-operative pain, presence and degree of post obturation pain. Presence of endodontic flare-ups (defined as either patient's report of pain not controlled with over the counter medication and or increasing swelling). The compiled data were analyzed using chi-square where applicable. P level < 0.05 was taken as significant. Ten endodontic flare-ups (8.1 %) were recorded in the multiple visits group compared to 19 (18,3%) flare-ups for the single visit group, P = 0.02. For both single and multiple visits procedures, there were statistically significant correlations between pre operative and post obturation pain (P = 0.002 and P = 0.0004 respectively). Teeth with vital pulps reported the lowest frequency of post obturation pain (48.8%), while those with non vital pulps were found to have the highest frequency oh post obturation pain (50,3%), P = 0.9. Although the present study reported higher incidences for post obturation pain and flare-ups following the single visit procedures, single visit endodontic therapy has been shown to be a safe and effective alternative to multiple visits treatment.

Comparison of Alcohol Use Disorder Screens During College Athlete Pre-Participation Evaluations.

PubMed

Majka, Erek; Graves, Travis; Diaz, Vanessa A; Player, Marty S; Dickerson, Lori M; Gavin, Jennifer K; Wessell, Andrea

2016-05-01

The US Preventive Services Task Force (USPSTF) recommends screening adults for alcohol misuse, a challenge among young adults who may not have regular primary care. The pre-participation evaluation (PPE) provides an opportunity for screening, but traditional screening tools require extra time in an already busy visit. The objective of this study was to compare the 10-item Alcohol Use Disorders Identification Test (AUDIT) with a single-question alcohol misuse screen in a population of college-aged athletes. This cross-sectional study was performed during an athletic PPE clinic at a college in the Southeastern United States among athletes ages 18 years and older. Written AUDIT and single-question screen "How many times in the past year have you had X or more drinks in a day?" (five for men, four for women) asked orally were administered to each participant. Sensitivity, specificity, and positive and negative predictive values for the single-question screen were compared to AUDIT. A total of 225 athletes were screened; 60% were female; 29% screened positive by AUDIT; 59% positive by single-question instrument. Males were more likely to screen positive by both methods. Compared to the AUDIT, the brief single-question screen had 92% sensitivity for alcohol misuse and 55% specificity. The negative predictive value of the single-question screen was 95% compared to AUDIT. A single-question screen for alcohol misuse in college-aged athletes had a high sensitivity and negative predictive value compared to the more extensive AUDIT screen. Ease of administration of this screening tool is ideal for use within the pre-participation physical among college-aged athletes who may not seek regular medical care.

Decoupling control of vehicle chassis system based on neural network inverse system

NASA Astrophysics Data System (ADS)

Wang, Chunyan; Zhao, Wanzhong; Luan, Zhongkai; Gao, Qi; Deng, Ke

2018-06-01

Steering and suspension are two important subsystems affecting the handling stability and riding comfort of the chassis system. In order to avoid the interference and coupling of the control channels between active front steering (AFS) and active suspension subsystems (ASS), this paper presents a composite decoupling control method, which consists of a neural network inverse system and a robust controller. The neural network inverse system is composed of a static neural network with several integrators and state feedback of the original chassis system to approach the inverse system of the nonlinear systems. The existence of the inverse system for the chassis system is proved by the reversibility derivation of Interactor algorithm. The robust controller is based on the internal model control (IMC), which is designed to improve the robustness and anti-interference of the decoupled system by adding a pre-compensation controller to the pseudo linear system. The results of the simulation and vehicle test show that the proposed decoupling controller has excellent decoupling performance, which can transform the multivariable system into a number of single input and single output systems, and eliminate the mutual influence and interference. Furthermore, it has satisfactory tracking capability and robust performance, which can improve the comprehensive performance of the chassis system.

Sunflower domestication alleles support single domestication center in eastern North America

PubMed Central

Blackman, Benjamin K.; Scascitelli, Moira; Kane, Nolan C.; Luton, Harry H.; Rasmussen, David A.; Bye, Robert A.; Lentz, David L.; Rieseberg, Loren H.

2011-01-01

Phylogenetic analyses of genes with demonstrated involvement in evolutionary transitions can be an important means of resolving conflicting hypotheses about evolutionary history or process. In sunflower, two genes have previously been shown to have experienced selective sweeps during its early domestication. In the present study, we identified a third candidate early domestication gene and conducted haplotype analyses of all three genes to address a recent, controversial hypothesis about the origin of cultivated sunflower. Although the scientific consensus had long been that sunflower was domesticated once in eastern North America, the discovery of pre-Columbian sunflower remains at archaeological sites in Mexico led to the proposal of a second domestication center in southern Mexico. Previous molecular studies with neutral markers were consistent with the former hypothesis. However, only two indigenous Mexican cultivars were included in these studies, and their provenance and genetic purity have been questioned. Therefore, we sequenced regions of the three candidate domestication genes containing SNPs diagnostic for domestication from large, newly collected samples of Mexican sunflower landraces and Mexican wild populations from a broad geographic range. The new germplasm also was genotyped for 12 microsatellite loci. Our evidence from multiple evolutionarily important loci and from neutral markers supports a single domestication event for extant cultivated sunflower in eastern North America. PMID:21844335

Drilling Rig Operation Mode Recognition by an Artificial Neuronet

NASA Astrophysics Data System (ADS)

Abu-Abed, Fares; Borisov, Nikolay

2017-11-01

The article proposes a way to develop a drilling rig operation mode classifier specialized to recognize pre-emergency situations appearable in commercial oil-and-gas well drilling. The classifier is based on the theory of image recognition and artificial neuronet taught on real geological and technological information obtained while drilling. To teach the neuronet, a modified backpropagation algorithm that can teach to reach the global extremum of a target function has been proposed. The target function was a relative recognition error to minimize in the teaching. Two approaches to form the drilling rig pre-emergency situation classifier based on a taught neuronet have been considered. The first one involves forming an output classifier of N different signals, each of which corresponds to a single recognizable situation and, and can be formed on the basis of the analysis of M indications, that is using a uniform indication vocabulary for all recognized situations. The second way implements a universal classifier comprising N specialized ones, each of which can recognize a single pre-emergency situation and having a single output.

Scater: pre-processing, quality control, normalization and visualization of single-cell RNA-seq data in R.

PubMed

McCarthy, Davis J; Campbell, Kieran R; Lun, Aaron T L; Wills, Quin F

2017-04-15

Single-cell RNA sequencing (scRNA-seq) is increasingly used to study gene expression at the level of individual cells. However, preparing raw sequence data for further analysis is not a straightforward process. Biases, artifacts and other sources of unwanted variation are present in the data, requiring substantial time and effort to be spent on pre-processing, quality control (QC) and normalization. We have developed the R/Bioconductor package scater to facilitate rigorous pre-processing, quality control, normalization and visualization of scRNA-seq data. The package provides a convenient, flexible workflow to process raw sequencing reads into a high-quality expression dataset ready for downstream analysis. scater provides a rich suite of plotting tools for single-cell data and a flexible data structure that is compatible with existing tools and can be used as infrastructure for future software development. The open-source code, along with installation instructions, vignettes and case studies, is available through Bioconductor at http://bioconductor.org/packages/scater . davis@ebi.ac.uk. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press.

A novel pre-sintering technique for the growth of Y-Ba-Cu-O superconducting single grains from raw metal oxides

NASA Astrophysics Data System (ADS)

Li, Jiawei; Shi, Yun-Hua; Dennis, Anthony R.; Namburi, Devendra Kumar; Durrell, John H.; Yang, Wanmin; Cardwell, David A.

2017-09-01

Most established top seeded melt growth (TSMG) processes of bulk, single grain Y-Ba-Cu-O (YBCO) superconductors are performed using a mixture of pre-reacted precursor powders. Here we report the successful growth of large, single grain YBCO samples by TSMG with good superconducting properties from a simple precursor composition consisting of a sintered mixture of the raw oxides. The elimination of the requirement to synthesize precursor powders in a separate process prior to melt processing has the potential to reduce significantly the cost of bulk superconductors, which is essential for their commercial exploitation. The growth morphology, microstructure, trapped magnetic field and critical current density, J c, at different positions within the sample and maximum levitation force of the YBCO single grains fabricated by this process are reported. Measurements of the superconducting properties show that the trapped filed can reach 0.45 T and that a zero field J c of 2.5 × 104 A cm-2 can be achieved in these samples. These values are comparable to those observed in samples fabricated using pre-reacted, high purity commercial oxide precursor powders. The experimental results are discussed and the possibility of further improving the melt process using raw oxides is outlined.

Meal frequency of pre-exercise carbohydrate feedings.

PubMed

Chryssanthopoulos, C; Petridou, A; Maridaki, M; Mougios, V

2008-04-01

This study compared the effect of single and multiple carbohydrate feedings before exercise on biochemical and physiological responses during exercise. Eight males performed 3 runs for 1 h at 70 % VO(2max) after consuming a meal containing 2.5 g carbohydrate per kg body mass in a single dose 3 h before exercise (SF), the same meal in 5 equal doses at 3, 2.5, 2, 1.5, and 1 h before exercise (MF), or a liquid placebo 3 h before exercise (P). RER and carbohydrate oxidation rates were higher in SF and MF compared to P trials, but there was no difference between SF and MF trials. Pre-exercise insulin was 2.0- and 3.4- fold higher in SF and MF, respectively, compared to P, and 1.7-fold higher in MF compared to SF. Glycerol and NEFA were higher in P compared to SF and MF trials before and at the end of exercise. In conclusion, a carbohydrate meal containing 2.5 g . kg(-1) ingested in doses over 3 h before running produced higher hyperinsulinemia pre-exercise than that produced when the meal was consumed in a single dose. Nevertheless, estimated carbohydrate utilization and adipose tissue lipolysis during exercise after multiple feedings seemed to be as high as after a single feeding.

Reticulated origin of domesticated emmer wheat supports a dynamic model for the emergence of agriculture in the fertile crescent.

PubMed

Civáň, Peter; Ivaničová, Zuzana; Brown, Terence A

2013-01-01

We used supernetworks with datasets of nuclear gene sequences and novel markers detecting retrotransposon insertions in ribosomal DNA loci to reassess the evolutionary relationships among tetraploid wheats. We show that domesticated emmer has a reticulated genetic ancestry, sharing phylogenetic signals with wild populations from all parts of the wild range. The extent of the genetic reticulation cannot be explained by post-domestication gene flow between cultivated emmer and wild plants, and the phylogenetic relationships among tetraploid wheats are incompatible with simple linear descent of the domesticates from a single wild population. A more parsimonious explanation of the data is that domesticated emmer originates from a hybridized population of different wild lineages. The observed diversity and reticulation patterns indicate that wild emmer evolved in the southern Levant, and that the wild emmer populations in south-eastern Turkey and the Zagros Mountains are relatively recent reticulate descendants of a subset of the Levantine wild populations. Based on our results we propose a new model for the emergence of domesticated emmer. During a pre-domestication period, diverse wild populations were collected from a large area west of the Euphrates and cultivated in mixed stands. Within these cultivated stands, hybridization gave rise to lineages displaying reticulated genealogical relationships with their ancestral populations. Gradual movement of early farmers out of the Levant introduced the pre-domesticated reticulated lineages to the northern and eastern parts of the Fertile Crescent, giving rise to the local wild populations but also facilitating fixation of domestication traits. Our model is consistent with the protracted and dispersed transition to agriculture indicated by the archaeobotanical evidence, and also with previous genetic data affiliating domesticated emmer with the wild populations in southeast Turkey. Unlike other protracted models, we assume that humans played an intuitive role throughout the process.

Enhancing QKD security with weak measurements

NASA Astrophysics Data System (ADS)

Farinholt, Jacob M.; Troupe, James E.

2016-10-01

Publisher's Note: This paper, originally published on 10/24/2016, was replaced with a corrected/revised version on 11/8/2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance. In the late 1980s, Aharonov and colleagues developed the notion of a weak measurement of a quantum observable that does not appreciably disturb the system.1, 2 The measurement results are conditioned on both the pre-selected and post-selected state of the quantum system. While any one measurement reveals very little information, by making the same measurement on a large ensemble of identically prepared pre- and post-selected (PPS) states and averaging the results, one may obtain what is known as the weak value of the observable with respect to that PPS ensemble. Recently, weak measurements have been proposed as a method of assessing the security of QKD in the well-known BB84 protocol.3 This weak value augmented QKD protocol (WV-QKD) works by additionally requiring the receiver, Bob, to make a weak measurement of a particular observable prior to his strong measurement. For the subset of measurement results in which Alice and Bob's measurement bases do not agree, the weak measurement results can be used to detect any attempt by an eavesdropper, Eve, to correlate her measurement results with Bob's. Furthermore, the well-known detector blinding attacks, which are known to perfectly correlate Eve's results with Bob's without being caught by conventional BB84 implementations, actually make the eavesdropper more visible in the new WV-QKD protocol. In this paper, we will introduce the WV-QKD protocol and discuss its generalization to the 6-state single qubit protocol. We will discuss the types of weak measurements that are optimal for this protocol, and compare the predicted performance of the 6- and 4-state WV-QKD protocols.

Cohort Profile Update: The China Jintan Child Cohort Study

PubMed Central

Liu, Jianghong; Cao, Siyuan; Chen, Zehang; Raine, Adrian; Hanlon, Alexandra; Ai, Yuexian; Zhou, Guoping; Yan, Chonghuai; Leung, Patrick W; McCauley, Linda; Pinto-Martin, Jennifer

2015-01-01

The China Jintan Child Cohort study began in 2004 with 1656 pre-school participants and a research focus on studying the impact of environmental exposures, such as lead, on children’s neurobehavioural outcomes. This population cohort now includes around 1000 of the original participants, who have been assessed three times over a period of 10 years. Since the original IJE cohort profile publication in 2010, participants have experienced a critical developmental transition from pre-school to school age and then adolescence. The study has also witnessed an increase in breadth and depth of data collection from the original aim of risk assessment. This cohort has added new directions to investigate the mechanisms and protective factors for the relationship between early health factors and child physical and mental health outcomes, with an emphasis on neurobehavioural consequences. The study now encompasses 11 domains, composed of repeated measures of the original variables and new domains of biomarkers, sleep, psychophysiology, neurocognition, personality, peer relationship, mindfulness and family dynamics. Depth of evaluation has increased from parent/teacher report to self/peer report and intergenerational family report. Consequently, the cohort has additional directions to include: (i) classmates of the original cohort participants for peer relationship assessment; and (ii) parental and grandparental measures to assess personality and dynamics within families. We welcome interest in our study and ask investigators to contact the corresponding author for additional information on data acquisition. PMID:26323725

Single-cell PCR of genomic DNA enabled by automated single-cell printing for cell isolation.

PubMed

Stumpf, F; Schoendube, J; Gross, A; Rath, C; Niekrawietz, S; Koltay, P; Roth, G

2015-07-15

Single-cell analysis has developed into a key topic in cell biology with future applications in personalized medicine, tumor identification as well as tumor discovery (Editorial, 2013). Here we employ inkjet-like printing to isolate individual living single human B cells (Raji cell line) and load them directly into standard PCR tubes. Single cells are optically detected in the nozzle of the microfluidic piezoelectric dispenser chip to ensure printing of droplets with single cells only. The printing process has been characterized by using microbeads (10µm diameter) resulting in a single bead delivery in 27 out of 28 cases and relative positional precision of ±350µm at a printing distance of 6mm between nozzle and tube lid. Process-integrated optical imaging enabled to identify the printing failure as void droplet and to exclude it from downstream processing. PCR of truly single-cell DNA was performed without pre-amplification directly from single Raji cells with 33% success rate (N=197) and Cq values of 36.3±2.5. Additionally single cell whole genome amplification (WGA) was employed to pre-amplify the single-cell DNA by a factor of >1000. This facilitated subsequent PCR for the same gene yielding a success rate of 64% (N=33) which will allow more sophisticated downstream analysis like sequencing, electrophoresis or multiplexing. Copyright © 2015 Elsevier B.V. All rights reserved.

Paleomagnetic Constraints on the age of the Lisheen Zn-Pb Deposit, Ireland: A Pre- Variscan Metamorphosed "MVT" Versus an Epigenetic Variscan Model for Ore Genesis

NASA Astrophysics Data System (ADS)

Pannalal, S. J.; Symons, D. T.; Sangster, D. F.

2009-05-01

Lower Carboniferous carbonate units in the Irish Midlands host major Zn-Pb ore deposits in two units, the Navan Group and the Waulsortian Limestone. The age and, therefore, the genesis of these ore deposits remains controversial because of the lack of absolute geochronological constraints. In addition, the effect of the Early Permian Variscan thermal episode, observed by elevated conodont color alteration indices in all Carboniferous strata in Ireland, on the Zn-Pb ore deposits is not clearly understood. This paleomagnetic study was undertaken to date and, thereby, constrain the genesis of the Waulsortian Limestone-hosted Lisheen Zn- Pb ore deposit. Specimens (432) from 12 sites in ore mineralization and 10 sites in host rocks at Lisheen were subjected to alternating-field and thermal step demagnetization protocols. Analysis of these specimens isolated a well-defined stable shallow and southerly-up paleomagnetic characteristic remanent magnetization (ChRM) direction. Saturation remanence tests, thermal decay data, and a paleomagnetic tilt test indicate a post-folding ChRM that is carried dominantly by single-domain magnetite. The ChRM directions from 8 host rock and 11 Zn-Pb mineralized sites are indistinguishable at 95% confidence, and give a mean paleopole at 41.6° S, 18.8° W (dp = 1.7°, dm = 3.3° ) with a paleomagnetic age of 277 ± 7 (2 σ) Ma on the apparent polar wander path for Laurentia in European coordinates. This Early Permian magnetization postdates peak-Variscan orogenic heating to ˜ 350° C in the surrounding region, suggesting two basic genetic models for Lisheen's Zn-Pb mineralization i.e. Variscan and metamorphosed pre-Variscan. The Variscan model, our preferred interpretation, suggests that the Zn-Pb mineralizing event occurred at 277 Ma during cooling from the regional Variscan thermal episode. This model, in conjunction with other thermal data, supports an entirely epigenetic origin that invokes a topographically-driven fluid flow, either from the south of Ireland or from closer to the deposit, that was modified by localized convection during the Variscan Orogeny. In contrast, the pre-Variscan model - favoured by previous authors - requires heating of the original Carboniferous Zn-Pb deposit to temperatures equivalent to chlorite-facies greenschist metamorphism during the Variscan Orogeny.

Supervision of Pre-Service Teacher: Using Internet Collaborative Tools to Support Their Return to Their Region of Origin

ERIC Educational Resources Information Center

Hamel, Christine

2012-01-01

As part of the bachelor's degree in Secondary Education at Laval University, students have the option of completing a final practicum in their region of origin. The structure of this final practicum requires new configurations in order to meet not only the requirements of practical training in teaching, but also the needs of remote communities who…

Neck strength recovery after a single bout of specific strengthening exercise.

PubMed

Netto, Kevin; Carstairs, Greg; Kidgell, Dawson; Aisbett, Brad

2010-08-01

To determine the level of neck strength decrement and the rate of strength recovery of the neck muscles after a single bout of specific neck conditioning exercise in both males and females. A decrement in neck strength may be evident after a bout of strengthening exercise. Intervention study with pre-and-post design. Biomechanics laboratory. Twenty healthy participants (10 male and 10 female, mean +/- standard deviation age 22 +/- 1.2 years). Participants performed a single bout of neck strengthening exercise. Neck strength testing using an isokinetic dynamometer was performed pre and at five time points (1 h, one, three, five and seven days) post-exercise to assess the level of neck strength decrement and neck strength recovery rate from pre-exercise levels. Statistically significant (p > or = 0.036) decreases in neck extension strength were recorded in all participants 1 h and one day post-exercise. The level of neck extension strength returned to pre-exercise levels three days post-exercise and surpassed pre-exercise levels five and seven days post-exercise. The male participants' neck flexion strength decrement and recovery followed a similar pattern to that displayed in neck extension but more variability in neck flexion strength recovery rates were recorded in the female participants in this study. The consistent strength recovery times for the male participants recorded in this study idealise the prescription of neck strengthening exercises in a periodised fashion. More investigation needs to be instigated for the female neck musculature as consistent strength recovery rates were not identified in this study. 2010 Elsevier Ltd. All rights reserved.

Pre-operative urinary tract infection: is it a risk factor for early surgical site infection with hip fracture surgery? A retrospective analysis.

PubMed

Yassa, Rafik Rd; Khalfaoui, Mahdi Y; Veravalli, Karunakar; Evans, D Alun

2017-03-01

The aims of the current study were to determine whether pre-operative urinary tract infections in patients presenting acutely with neck of femur fractures resulted in a delay to surgery and whether such patients were at increased risk of developing post-operative surgical site infections. A retrospective review of all patients presenting with a neck of femur fracture, at a single centre over a one-year period. The hospital hip fracture database was used as the main source of data. UK University Teaching Hospital. All patients ( n  = 460) presenting across a single year study period with a confirmed hip fracture. The presence of pre-operative urinary tract infection, the timing of surgical intervention, the occurrence of post-operative surgical site infection and the pathogens identified. A total of 367 patients were operated upon within 24 hours of admission. Urinary infections were the least common cause of delay. A total of 99 patients (21.5%) had pre-operative urinary tract infection. Post-operatively, a total of 57 (12.4%) patients developed a surgical site infection. Among the latter, 31 (54.4%) did not have a pre-operative urinary infection, 23 (40.4%) patients had a pre-operative urinary tract infection, 2 had chronic leg ulcers and one patient had a pre-operative chest infection. Statistically, there was a strong relationship between pre-operative urinary tract infection and the development of post-operative surgical site infection ( p -value: 0.0005). The results of our study indicate that pre-operative urinary tract infection has a high prevalence amongst those presenting with neck of femur fractures, and this is a risk factor for the later development of post-operative surgical site infection.

Evaluation of biomarkers for the prediction of pre-eclampsia in women with type 1 diabetes mellitus: A systematic review.

PubMed

Wotherspoon, Amy C; Young, Ian S; McCance, David R; Holmes, Valerie A

2016-07-01

Pre-eclampsia is a leading cause of maternal and perinatal morbidity and mortality. Women with type 1 diabetes are considered a high-risk group for developing pre-eclampsia. Much research has focused on biomarkers as a means of screening for pre-eclampsia in the general maternal population; however, there is a lack of evidence for women with type 1 diabetes. To undertake a systematic review to identify potential biomarkers for the prediction of pre-eclampsia in women with type 1 diabetes. We searched Medline, EMBASE, Maternity and Infant Care, Scopus, Web of Science and CINAHL SELECTION CRITERIA: Studies were included if they measured biomarkers in blood or urine of women who developed pre-eclampsia and had pre-gestational type 1 diabetes mellitus Data collection and analysis A narrative synthesis was adopted as a meta-analysis could not be performed, due to high study heterogeneity. A total of 72 records were screened, with 21 eligible studies being included in the review. A wide range of biomarkers was investigated and study size varied from 34 to 1258 participants. No single biomarker appeared to be effective in predicting pre-eclampsia; however, glycaemic control was associated with an increased risk while a combination of angiogenic and anti-angiogenic factors seemed to be potentially useful. Limited evidence suggests that combinations of biomarkers may be more effective in predicting pre-eclampsia than single biomarkers. Further research is needed to verify the predictive potential of biomarkers that have been measured in the general maternal population, as many studies exclude women with diabetes preceding pregnancy. Copyright © 2016 Elsevier Inc. All rights reserved.

PREMAQ: A NEW PRE-PROCESSOR TO CMAQ FOR AIR-QUALITY FORECASTING

EPA Science Inventory

A new pre-processor to CMAQ (PREMAQ) has been developed as part of the national air-quality forecasting system. PREMAQ combines the functionality of MCIP and parts of SMOKE in a single real-time processor. PREMAQ was specifically designed to link NCEP's Eta model with CMAQ, and...

Conventional radiotherapy with concurrent weekly Cisplatin in locally advanced head and neck cancers of squamous cell origin - a single institution experience.

PubMed

Dimri, Kislay; Pandey, Awadhesh Kumar; Trehan, Romeeta; Rai, Bhavana; Kumar, Anup

2013-01-01

Platinum based concurrent chemo-radiation is the de-facto standard of care in the non-surgical management of locally-advanced head and neck cancer of squamous origin. Three-weekly single agent cisplatin at 100 mg/m2 concurrent with radical radiotherapy has demonstrated consistent improvement in loco-regional control and survival. This improvement is however at the cost of considerable hematologic toxicity and poor overall compliance. The routine use of this regime is improbable in developing countries with limited resources. We therefore aimed to determine the safety and efficacy of an alternative regime of weekly cisplatin and concurrent radiotherapy in such patients. January-05 and April-12, 188 patients of locally-advanced head and neck cancer of squamous origin were treated with concurrent weekly-cisplatin at 35 mg/m2 and conventional radiotherapy 60-66Gy/30-33 fractions/5 days per week. Overall, 95% patients received planned doses of RT while 74% completed within the stipulated overall treatment time of <50 days. Eighty-two percent received at-least 5 weekly cycles. Grade-III/IV mucositis was seen in 58%/9% respectively, which resulted in mean weight loss of 9.2% from a pre-treatment mean of 54.5 kg. Grade-III hematologic toxicity-0.5%; grade II nephrotoxicity-2.5% and grade III emesis-3% were also seen. Grade-III/IV subcutaneous toxicity-10%/1% and grade-III/IV xerostomia-10%/0% were observed. Complete responses at the primary site, regional nodes and overall disease were seen in 86%, 89% and 83% patients respectively. The median and 5-years disease-free survival were 26 months and 39.4% respectively, while the median and overall survival were 27 months and 41.8% respectively. Weekly-cisplatin at 35 mg /m2 when delivered concurrently with conventional radical RT (at-least 66y/33 fractions) in locally-advanced head and neck cancer is well tolerated with minimal hematologic and neprologic toxicity and can be routinely delivered on an out-patient basis. It is an effective alternative to the standard 3-weekly cisplatin especially in the context of developing countries.

Mutations in CDC45, Encoding an Essential Component of the Pre-initiation Complex, Cause Meier-Gorlin Syndrome and Craniosynostosis.

PubMed

Fenwick, Aimee L; Kliszczak, Maciej; Cooper, Fay; Murray, Jennie; Sanchez-Pulido, Luis; Twigg, Stephen R F; Goriely, Anne; McGowan, Simon J; Miller, Kerry A; Taylor, Indira B; Logan, Clare; Bozdogan, Sevcan; Danda, Sumita; Dixon, Joanne; Elsayed, Solaf M; Elsobky, Ezzat; Gardham, Alice; Hoffer, Mariette J V; Koopmans, Marije; McDonald-McGinn, Donna M; Santen, Gijs W E; Savarirayan, Ravi; de Silva, Deepthi; Vanakker, Olivier; Wall, Steven A; Wilson, Louise C; Yuregir, Ozge Ozalp; Zackai, Elaine H; Ponting, Chris P; Jackson, Andrew P; Wilkie, Andrew O M; Niedzwiedz, Wojciech; Bicknell, Louise S

2016-07-07

DNA replication precisely duplicates the genome to ensure stable inheritance of genetic information. Impaired licensing of origins of replication during the G1 phase of the cell cycle has been implicated in Meier-Gorlin syndrome (MGS), a disorder defined by the triad of short stature, microtia, and a/hypoplastic patellae. Biallelic partial loss-of-function mutations in multiple components of the pre-replication complex (preRC; ORC1, ORC4, ORC6, CDT1, or CDC6) as well as de novo stabilizing mutations in the licensing inhibitor, GMNN, cause MGS. Here we report the identification of mutations in CDC45 in 15 affected individuals from 12 families with MGS and/or craniosynostosis. CDC45 encodes a component of both the pre-initiation (preIC) and CMG helicase complexes, required for initiation of DNA replication origin firing and ongoing DNA synthesis during S-phase itself, respectively, and hence is functionally distinct from previously identified MGS-associated genes. The phenotypes of affected individuals range from syndromic coronal craniosynostosis to severe growth restriction, fulfilling diagnostic criteria for Meier-Gorlin syndrome. All mutations identified were biallelic and included synonymous mutations altering splicing of physiological CDC45 transcripts, as well as amino acid substitutions expected to result in partial loss of function. Functionally, mutations reduce levels of full-length transcripts and protein in subject cells, consistent with partial loss of CDC45 function and a predicted limited rate of DNA replication and cell proliferation. Our findings therefore implicate the preIC as an additional protein complex involved in the etiology of MGS and connect the core cellular machinery of genome replication with growth, chondrogenesis, and cranial suture homeostasis. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Effects of seasonal variability in across- and alongshore transport of anchoveta ( Engraulis ringens) larvae on model-based pre-recruitment indices off central Chile

NASA Astrophysics Data System (ADS)

Parada, Carolina; Colas, Francois; Soto-Mendoza, Samuel; Castro, Leonardo

2012-01-01

An individual-based model (IBM) of anchoveta ( Engraulis ringens) larvae was coupled to a climatological hydrodynamic (Regional Oceanic Modeling System, ROMS) model for central-southern Chile to answer the question as to whether or not across- and alongshore transport off central-southern Chile enhances retention in the spawning areas during the winter and summer reproductive periods, using model-based pre-recruitment indices (simulated transport success to nursery areas). The hydrodynamic model validation showed that ROMS captures the mean Seas Surface Temperature and Eddie Kinetic Energy observed in satellite-based data over the entire region. The IBM was used to simulate the transport of eggs and larvae from spawning zones in central Chile (Constitución, Dichato, Gulf of Arauco and Lebu-Corral) to historical nursery areas (HRZ, region between 35°S and 37°S). Model results corroborated HRZ as the most successful pre-recruitment zone (particles originated in the Dichato and Gulf of Arauco spawning areas), as well as identifying Lebu-Corral as a zone of high retention with a high associated pre-recruitment index (particles originated in the Lebu-Corral spawning zone). The highest pre-recruitment values were mainly found in winter. The Constitución and Dichato spawning zones displayed a typical summer upwelling velocity pattern, while the Gulf of Arauco in summertime showed strong offshore and alongshore velocity components. The Lebu-Corral region in winter presented important near-surface cross-shore transport towards the coast (associated with downwelling events), this might be one of the major mechanisms leading to high retention levels and a high pre-recruitment index for Lebu-Corral spawning zone. The limitations of the modeling approach are discussed and put into perspective for future work.

Origin of the defects-induced ferromagnetism in un-doped ZnO single crystals

NASA Astrophysics Data System (ADS)

Zhan, Peng; Xie, Zheng; Li, Zhengcao; Wang, Weipeng; Zhang, Zhengjun; Li, Zhuoxin; Cheng, Guodong; Zhang, Peng; Wang, Baoyi; Cao, Xingzhong

2013-02-01

We clarified, in this Letter, that in un-doped ZnO single crystals after thermal annealing in flowing argon, the defects-induced room-temperature ferromagnetism was originated from the surface defects and specifically, from singly occupied oxygen vacancies denoted as F+, by the optical and electrical properties measurements as well as positron annihilation analysis. In addition, a positive linear relationship was observed between the ferromagnetism and the F+ concentration, which is in support with the above clarification.

Single left coronary artery with separate origins of proximal and distal right coronary arteries from left anterior descending and circumflex arteries--a previously undescribed coronary circulation.

PubMed

Kaul, Pankaj; Javangula, Kalyana

2007-04-20

A single left coronary artery with right coronary artery arising from either left main stem (LMS) or left anterior descending artery (LAD) or circumflex artery (Cx) is an extremely rare coronary anomaly. This is the first report of separate origins of proximal and distal RCA from LAD and circumflex arteries respectively in a patient with a single left coronary artery. This 57 year old patient presented with unstable angina and severe stenotic disease of LAD and Cx arteries and underwent urgent successful quadruple coronary artery bypass grafting. The anomalies of right coronary artery in terms of their origin, number and distribution are reviewed.

Delphian node metastasis in head and neck cancers--oracle or myth?

PubMed

Iyer, N Gopalakrishna; Shaha, Ashok R; Ferlito, Alfio; Thomas Robbins, K; Medina, Jesus E; Silver, Carl E; Rinaldo, Alessandra; Takes, Robert P; Suárez, Carlos; Rodrigo, Juan P; Bradley, Patrick J; Werner, Jochen A

2010-09-15

Delphian node (DN) refers to the pre-laryngeal or pre-cricoid nodal tissue often identified during laryngeal or thyroid surgery. The original nomenclature is based on the assumption that metastasis to this node was predictive of aggressive disease and poor outcome for patients. In this article, we review the existing literature on the topic to determine the significance of DN metastasis in laryngeal, hypopharyngeal and thyroid cancers. (c) 2010 Wiley-Liss, Inc.

Effects of pre-creep on the dislocations of 316LN Austenite stainless steel

NASA Astrophysics Data System (ADS)

Pei, Hai-xiang; Hui, Jun; Hua, Hou; Feng, Zai-xin; Xu, Xiao-long

2017-09-01

The 316LN Austenite stainless steels (316LNASS) were pre-creep treated, the evolution of microstructure were investigated. The samples were pre-creep at 593 K and from 500 to 2000 h at 873 K with a stress in the range of 20 to 150 MPa, Then the evolution of microstructure and precipitation were investigated by optical microscope (OM), and transmission electron microscope (TEM). The results show that the crystal surface slipping resulted in dislocations and original dislocations decomposition during the pre-creep process, and generate quadrilateral or hexagonal dislocation network was obviously. The sub-grain boundary gradually became narrow with the increasing of pre-creep treatment time and temperature. When the pre-creep temperature was 593 K and 873 K, dislocation network gradually disappear with the increasing of pre-creep time and load. When the pre-creep temperature was 873 K under 120 MPa, and the treatment time was 2000 h, the hexagonal dislocation network (HDN) would completely disappeared. When the pre-creep temperature was 593 K under 20 MPa, and the treatment time was 500 h, the quadrilateral dislocation network (QDN) would completely disappeared.

Zinc oxide nanowire gamma ray detector with high spatiotemporal resolution

NASA Astrophysics Data System (ADS)

Mayo, Daniel C.; Nolen, J. Ryan; Cook, Andrew; Mu, Richard R.; Haglund, Richard F.

2016-03-01

Conventional scintillation detectors are typically single crystals of heavy-metal oxides or halides doped with rare-earth ions that record the recombination of electron-hole pairs by photon emission in the visible to ultraviolet. However, the light yields are typically low enough to require photomultiplier detection with the attendant instrumental complications. Here we report initial studies of gamma ray detection by zinc oxide (ZnO) nanowires, grown by vapor-solid deposition. The nanowires grow along the c-axis in a wurtzite structure; they are typically 80 nm in diameter and have lengths of 1- 2 μm. The nanowires are single crystals of high quality, with a photoluminescence (PL) yield from band-edge exciton emission in the ultraviolet that is typically one hundred times larger than the PL yield from defect centers in the visible. Nanowire ensembles were irradiated by 662 keV gamma rays from a Cs-137 source for periods of up to ten hours; gamma rays in this energy range interact by Compton scattering, which in ZnO creates F+ centers that relax to form singly-charged positive oxygen vacancies. Following irradiation, we fit the PL spectra of the visible emission with a sum of Gaussians at the energies of the known defects. We find highly efficient PL from the irradiated area, with a figure of merit approaching 106 photons/s/MeV of deposited energy. Over a period of days, the singly charged O+ vacancies relax to the more stable doubly charged O++ vacancies. However, the overall defect PL returns to pre-irradiation values after about a week, as the vacancies diffuse to the surface of these very thin nanowires, indicating that a self-healing process restores the nanowires to their original state.

MHD simulations of homologous and cannibalistic coronal mass ejections

NASA Astrophysics Data System (ADS)

Fan, Yuhong; Chatterjee, Piyali

2014-06-01

We present magneto-hydrodynamic simulations of the development of a homologous sequence of coronal mass ejections (CMEs) and demonstrate their so-called cannibalistic behavior. These CMEs originate from the repeated formations and partial eruptions of kink unstable flux ropes as a result of the continued emergence of a twisted flux rope across the lower boundary into a pre-existing coronal potential arcade field. The simulations show that a CME erupting into the open magnetic field created by a preceding CME has a higher speed, and therefore tends to be cannibalistic, catching up and merging with the preceding one into a single fast CME. All the CMEs attained speeds of about 1000 km/s as they exit the domain. The reformation of a twisted flux rope after each CME eruption during the sustained flux emergence can naturally explain the X-ray observations of repeated reformations of sigmoids and “sigmoid-under-cusp” configurations at a low-coronal source of homologous CMEs.

Physical re-examination of parameters on a molecular collisions-based diffusion model for diffusivity prediction in polymers.

PubMed

Ohashi, Hidenori; Tamaki, Takanori; Yamaguchi, Takeo

2011-12-29

Molecular collisions, which are the microscopic origin of molecular diffusive motion, are affected by both the molecular surface area and the distance between molecules. Their product can be regarded as the free space around a penetrant molecule defined as the "shell-like free volume" and can be taken as a characteristic of molecular collisions. On the basis of this notion, a new diffusion theory has been developed. The model can predict molecular diffusivity in polymeric systems using only well-defined single-component parameters of molecular volume, molecular surface area, free volume, and pre-exponential factors. By consideration of the physical description of the model, the actual body moved and which neighbor molecules are collided with are the volume and the surface area of the penetrant molecular core. In the present study, a semiempirical quantum chemical calculation was used to calculate both of these parameters. The model and the newly developed parameters offer fairly good predictive ability. © 2011 American Chemical Society

Model for the orientational ordering of the plant microtubule cortical array

NASA Astrophysics Data System (ADS)

Hawkins, Rhoda J.; Tindemans, Simon H.; Mulder, Bela M.

2010-07-01

The plant microtubule cortical array is a striking feature of all growing plant cells. It consists of a more or less homogeneously distributed array of highly aligned microtubules connected to the inner side of the plasma membrane and oriented transversely to the cell growth axis. Here, we formulate a continuum model to describe the origin of orientational order in such confined arrays of dynamical microtubules. The model is based on recent experimental observations that show that a growing cortical microtubule can interact through angle dependent collisions with pre-existing microtubules that can lead either to co-alignment of the growth, retraction through catastrophe induction or crossing over the encountered microtubule. We identify a single control parameter, which is fully determined by the nucleation rate and intrinsic dynamics of individual microtubules. We solve the model analytically in the stationary isotropic phase, discuss the limits of stability of this isotropic phase, and explicitly solve for the ordered stationary states in a simplified version of the model.

High-level expression of Camelid nanobodies in Nicotiana benthamiana.

PubMed

Teh, Yi-Hui Audrey; Kavanagh, Tony A

2010-08-01

Nanobodies (or VHHs) are single-domain antigen-binding fragments derived from Camelid heavy chain-only antibodies. Their small size, monomeric behaviour, high stability and solubility, and ability to bind epitopes not accessible to conventional antibodies make them especially suitable for many therapeutic and biotechnological applications. Here we describe high-level expression, in Nicotiana benthamiana, of three versions of an anti-hen egg white lysozyme (HEWL) nanobody which include the original VHH from an immunized library (cAbLys3), a codon-optimized derivative, and a codon-optimized hybrid nanobody comprising the CDRs of cAbLys3 grafted onto an alternative 'universal' nanobody framework. His6- and StrepII-tagged derivatives of each nanobody were targeted for accumulation in the cytoplasm, chloroplast and apoplast using different pre-sequences. When targeted to the apoplast, intact functional nanobodies accumulated at an exceptionally high level (up to 30% total leaf protein), demonstrating the great potential of plants as a nanobody production system.

Severe motor and vocal tics controlled with Sativex®.

PubMed

Trainor, David; Evans, Lois; Bird, Rupert

2016-12-01

A single case report on cannabinoid treatment for treatment-resistant Tourette syndrome (TS). Our subject received 10.8 mg Tetrahydocannabinol and 10 mg cannabidiol daily, in the form of two oro-mucosal sprays of 'Sativex ® ', twice daily. Assessment was pre-treatment and at week one, two, and four during treatment. He completed the Yale Global Tic Severity Scale as a subjective measure, and was videoed at each stage. The videos were objectively rated by two assessors, blind to the stage of treatment, using the Original Rush Videotape Rating Scale. Both subjective and objective measures demonstrated marked improvement in the frequency and severity of motor and vocal tics post-treatment. There was good interrater reliability of results. Our results support previous research suggesting that cannabinoids are a safe and effective treatment for TS and should be considered in treatment-resistant cases. Further studies are needed to substantiate our findings. © The Royal Australian and New Zealand College of Psychiatrists 2016.

CoP/WS2 nanoflake heterostructures as efficient electrocatalysts for significant improvement in hydrogen evolution activity

NASA Astrophysics Data System (ADS)

Chen, Yajie; Kang, Chuanhong; Wang, Ruihong; Ren, Zhiyu; Fu, Huiying; Xiao, Yuting; Tian, Guohui

2018-06-01

The CoP/WS2 nanoflake composites were synthesized via the sulfuration and subsequent phosphidation using the pre-prepared WO2.72 nanowires as precursors. Originally, WO2.72 nanowires were prepared and followed by sulfuration to obtain WS2 nanoflakes. The as-prepared WS2 nanoflakes were used as substrates, on which the Co3O4 nanoparticles were uniformly anchored to construct the Co3O4/WS2 nanoflakes. Finally, the Co3O4/WS2 composites were subjected to phosphidation and in-situ converted into CoP/WS2 nanoflakes. Because of the dual functionalities of both CoP and WS2, the abundant interfaces as well as their synergy, the CoP/WS2 nanoflakes exhibited much higher electrocatalytic activity, smaller overpotential (-81 mV), lower Tafel slope (62 mV decade-1), and higher stability toward hydrogen-evolution reaction than those for the single CoP and WS2.

A new simple /spl infin/OH neuron model as a biologically plausible principal component analyzer.

PubMed

Jankovic, M V

2003-01-01

A new approach to unsupervised learning in a single-layer neural network is discussed. An algorithm for unsupervised learning based upon the Hebbian learning rule is presented. A simple neuron model is analyzed. A dynamic neural model, which contains both feed-forward and feedback connections between the input and the output, has been adopted. The, proposed learning algorithm could be more correctly named self-supervised rather than unsupervised. The solution proposed here is a modified Hebbian rule, in which the modification of the synaptic strength is proportional not to pre- and postsynaptic activity, but instead to the presynaptic and averaged value of postsynaptic activity. It is shown that the model neuron tends to extract the principal component from a stationary input vector sequence. Usually accepted additional decaying terms for the stabilization of the original Hebbian rule are avoided. Implementation of the basic Hebbian scheme would not lead to unrealistic growth of the synaptic strengths, thanks to the adopted network structure.

Advanced Extraction of Spatial Information from High Resolution Satellite Data

NASA Astrophysics Data System (ADS)

Pour, T.; Burian, J.; Miřijovský, J.

2016-06-01

In this paper authors processed five satellite image of five different Middle-European cities taken by five different sensors. The aim of the paper was to find methods and approaches leading to evaluation and spatial data extraction from areas of interest. For this reason, data were firstly pre-processed using image fusion, mosaicking and segmentation processes. Results going into the next step were two polygon layers; first one representing single objects and the second one representing city blocks. In the second step, polygon layers were classified and exported into Esri shapefile format. Classification was partly hierarchical expert based and partly based on the tool SEaTH used for separability distinction and thresholding. Final results along with visual previews were attached to the original thesis. Results are evaluated visually and statistically in the last part of the paper. In the discussion author described difficulties of working with data of large size, taken by different sensors and different also thematically.

Automatic Structural Parcellation of Mouse Brain MRI Using Multi-Atlas Label Fusion

PubMed Central

Ma, Da; Cardoso, Manuel J.; Modat, Marc; Powell, Nick; Wells, Jack; Holmes, Holly; Wiseman, Frances; Tybulewicz, Victor; Fisher, Elizabeth; Lythgoe, Mark F.; Ourselin, Sébastien

2014-01-01

Multi-atlas segmentation propagation has evolved quickly in recent years, becoming a state-of-the-art methodology for automatic parcellation of structural images. However, few studies have applied these methods to preclinical research. In this study, we present a fully automatic framework for mouse brain MRI structural parcellation using multi-atlas segmentation propagation. The framework adopts the similarity and truth estimation for propagated segmentations (STEPS) algorithm, which utilises a locally normalised cross correlation similarity metric for atlas selection and an extended simultaneous truth and performance level estimation (STAPLE) framework for multi-label fusion. The segmentation accuracy of the multi-atlas framework was evaluated using publicly available mouse brain atlas databases with pre-segmented manually labelled anatomical structures as the gold standard, and optimised parameters were obtained for the STEPS algorithm in the label fusion to achieve the best segmentation accuracy. We showed that our multi-atlas framework resulted in significantly higher segmentation accuracy compared to single-atlas based segmentation, as well as to the original STAPLE framework. PMID:24475148

Independent CMEs from a Single Solar Active Region - The Case of the Super-Eruptive NOAA AR11429

NASA Astrophysics Data System (ADS)

Chintzoglou, Georgios; Patsourakos, Spiros; Vourlidas, Angelos

2014-06-01

In this investigation we study AR 11429, the origin of the twin super-fast CME eruptions of 07-Mar-2012. This AR fulfills all the requirements for the 'perfect storm'; namely, Hale's law incompatibility and a delta-magnetic configuration. In fact, during its limb-to-limb transit, AR 11429 spawned several eruptions which caused geomagnetic storms, including the biggest in Cycle 24 so far. Magnetic Flux Ropes (MFRs) are twisted magnetic structures in the corona, best seen in ~10MK hot plasma emission and are often considered as the culprit causing such super-eruptions. However, their 'dormant' existence in the solar atmosphere (i.e. prior to eruptions), is a matter of strong debate. Aided by multi-wavelength and multi-spacecraft observations (SDO/HMI & AIA, HINODE/SOT/SP, STEREO B/EUVI) and by using a Non-Linear Force-Free (NLFFF) model for the coronal magnetic field, our work shows two separate, weakly-twisted magnetic flux systems which suggest the existence of possible pre-eruption MFRs.

System performance enhancement with pre-distorted OOFDM signal waveforms in DM/DD systems.

PubMed

Sánchez, C; Ortega, B; Capmany, J

2014-03-24

In this work we propose a pre-distortion technique for the mitigation of the nonlinear distortion present in directly modulated/detected OOFDM systems and explore the system performance achieved under varying system parameters. Simulation results show that the proposed pre-distortion technique efficiently mitigates the nonlinear distortion, achieving transmission information rates around 40 Gbits/s and 18.5 Gbits/s over 40 km and 100 km of single mode fiber links, respectively, under optimum operating conditions. Moreover, the proposed pre-distortion technique can potentially provide higher system performance to that obtained with nonlinear equalization at the receiver.

Identification of pre-leukaemic haematopoietic stem cells in acute leukaemia.

PubMed

Shlush, Liran I; Zandi, Sasan; Mitchell, Amanda; Chen, Weihsu Claire; Brandwein, Joseph M; Gupta, Vikas; Kennedy, James A; Schimmer, Aaron D; Schuh, Andre C; Yee, Karen W; McLeod, Jessica L; Doedens, Monica; Medeiros, Jessie J F; Marke, Rene; Kim, Hyeoung Joon; Lee, Kwon; McPherson, John D; Hudson, Thomas J; Brown, Andrew M K; Yousif, Fouad; Trinh, Quang M; Stein, Lincoln D; Minden, Mark D; Wang, Jean C Y; Dick, John E

2014-02-20

In acute myeloid leukaemia (AML), the cell of origin, nature and biological consequences of initiating lesions, and order of subsequent mutations remain poorly understood, as AML is typically diagnosed without observation of a pre-leukaemic phase. Here, highly purified haematopoietic stem cells (HSCs), progenitor and mature cell fractions from the blood of AML patients were found to contain recurrent DNMT3A mutations (DNMT3A(mut)) at high allele frequency, but without coincident NPM1 mutations (NPM1c) present in AML blasts. DNMT3A(mut)-bearing HSCs showed a multilineage repopulation advantage over non-mutated HSCs in xenografts, establishing their identity as pre-leukaemic HSCs. Pre-leukaemic HSCs were found in remission samples, indicating that they survive chemotherapy. Therefore DNMT3A(mut) arises early in AML evolution, probably in HSCs, leading to a clonally expanded pool of pre-leukaemic HSCs from which AML evolves. Our findings provide a paradigm for the detection and treatment of pre-leukaemic clones before the acquisition of additional genetic lesions engenders greater therapeutic resistance.

The annealing investigation on morphology and photoluminescence properties of In2O3 1-D nanostructures in resistive evaporation mechanism

NASA Astrophysics Data System (ADS)

Shariati, Mohsen; Ghafouri, Vahid

2014-02-01

Synthesis of In2O3 nanostructures grown on Si substrate by the resistive evaporation of metallic indium granules followed by dry oxidation process has been articulated. To prepare nucleation growth sites, selected samples pre-annealed around indium melting point in free-oxygen atmosphere and then to fabricate 1-D nanostructures, they annealed in a horizontal thermal furnace in presence of argon and oxygen. For comparison, one sample, the same origin as initially pre-annealed samples, was excluded in pre-annealing process but presented in annealing step. Characterization of the products with FESEM revealed that the pre-annealed obtained nanostructures are mostly nanorod and nanowire with different morphologies. For the comparative sample, no 1-D structures achieved. X-ray diffraction (XRD) patterns for pre-annealed samples indicated that they are crystalline and the comparative one is polycrystalline. Photoluminescence (PL) measurements carried out at room temperature revealed that emission band shifted to shorter wavelength from pre-annealed samples to comparative one.

Evaluating a Pre-Session Homework Exercise in a Standalone Information Literacy Class

ERIC Educational Resources Information Center

Goetz, Joseph E.; Barber, Catherine R.

2015-01-01

In this study, researchers evaluate a homework exercise assigned before a standalone information literacy session. Students in a Master of Education program completed a worksheet using the ERIC database thesaurus. The researchers conducted pre- and posttests within a single library session to assess student learning, using a control group for…

The Perceived Impact of Mindfulness Instruction on Pre-Service Elementary Teachers

ERIC Educational Resources Information Center

Brown, Rachel

2017-01-01

This study explored the self-reported effects of mindfuless instruction on pre-service elementary teachers in the context of a literacy education course. Twenty female undergraduates participated in a study that occurred over the course of a single semester in one university. Analysis of the results indicated that students were not significantly…

Effect of single-dose albendazole and vitamin A supplementation on the iron status of pre-school children in Sichuan, China.

PubMed

Chen, Ke; Xie, Hu Mina; Tian, Weizheng; Zheng, Xiaoling; Jiang, Alice C

2016-04-01

The aim of this study was to explore the effect of single-dose albendazole and vitamin A intervention on the anaemic status and Fe metabolism of pre-school children. This study was a randomised, placebo-controlled and double-blinded intervention trial. All eligible anaemic pre-school children were randomly divided into three groups: group 1 received no intervention, which served as the control group, group 2 received 400 mg single-dose albendazole administration and group 3 received a 60000 μg vitamin A capsule combined with 400 mg single-dose albendazole at the beginning of the study. The follow-up period was for 6 months. Anthropometry and biochemical index about Fe metabolism were measured before and after intervention. A total of 209 pre-school anaemic children were randomly divided into three intervention groups (sixty-four, sixty-two and sixty for groups 1, 2 and 3, respectively). The mean age of the children in the study was 4·4 (sd 0·7) years and 50·5 % of the children were female (94/186). After a follow-up period of 6 months, the levels of serum retinol, ferritin, transferrin receptor-ferritin index and body total Fe content of children in group 3 were significantly higher compared with children in groups 1 and 2 (P<0·05). Moreover, the proportion of vitamin A deficiency, marginal vitamin A deficiency and Fe deficiency among children in group 3 were markedly lower compared with children in groups 1 and 2 (P<0·05). Albendazole plus vitamin A administration showed more efficacy on the improvement of serum retinol and Fe metabolic status.

Vehicle speed affects both pre-skid braking kinematics and average tire/roadway friction.

PubMed

Heinrichs, Bradley E; Allin, Boyd D; Bowler, James J; Siegmund, Gunter P

2004-09-01

Vehicles decelerate between brake application and skid onset. To better estimate a vehicle's speed and position at brake application, we investigated how vehicle deceleration varied with initial speed during both the pre-skid and skidding intervals on dry asphalt. Skid-to-stop tests were performed from four initial speeds (20, 40, 60, and 80 km/h) using three different grades of tire (economy, touring, and performance) on a single vehicle and a single road surface. Average skidding friction was found to vary with initial speed and tire type. The post-brake/pre-skid speed loss, elapsed time, distance travelled, and effective friction were found to vary with initial speed. Based on these data, a method using skid mark length to predict vehicle speed and position at brake application rather than skid onset was shown to improve estimates of initial vehicle speed by up to 10 km/h and estimates of vehicle position at brake application by up to 8 m compared to conventional methods that ignore the post-brake/pre-skid interval. Copyright 2003 Elsevier Ltd.

Geologic support for the putative Borealis basin (Mega-Impact) on Mars

NASA Astrophysics Data System (ADS)

Bleamaster, L. F.

2008-12-01

A series of recent papers (all in Nature v. 453) using Martian gravity and topography [Andrews-Hanna et al., 2008], 3-D hydrodynamic simulations [Marinova et al., 2008], and 2-D hydrocode models [Nimmo et al., 2008] have eloquently reintroduced the single mega-impact hypothesis for the formation of the Martian hemispheric dichotomy boundary. Although geophysical models often return non-unique solutions, the coalition front presented by these three independent methods to test such a hypothesis lends credibility and demands further evaluation. The central tenet of these works is the proposition that an elliptical basin (long axis 10,600km, ellipticity 1.25) centered at 67N, 208E marks the pre-Tharsis crustal thickness transition and thus the real dichotomy boundary. Evaluation of this new boundary with respect to the geologic record offers new avenues, especially since geologic tests of the mega-impact hypothesis have mostly proved inconclusive because of Mars' multi-stage and multi-process geologic history. Within this survey, a slightly larger ellipse with a long axis of 12,500 km, ellipticity of 1.48, and centered at 65.3N, 250E expands the putative Borealis impact basin (which does not necessarily represent the transient or final impact cavity dimensions, but defines a potential 'affected zone') while maintaining agreement with the original observations with respect to gravity and topography. The 'affected zone' can be defined by basement structure that may become susceptible to later deformation, or it may in fact have been the paleo- topographic expression of the basin. By expanding the overall area (nearly twice the area of the original mega-impact basin proposed by Wilhelms and Squyres in 1984) several geologic features become significant in evaluating the mega-impact story. 1) Valles Marineris is concentric to the putative basin interior and parallels the ellipse margin suggesting that it is the structural manifestation of localized crustal relaxation of the Tharsis volcanic pile over pre-existing basement structure related to Borealis basin subsidence. The present day Valles Marineris may actually represent the 'missing portion' of the original crustal dichotomy trace underneath Tharsis. 2) The 'great faults' (Connerney et al., 2005) that offset the magnetic field pattern radiate from near the center of the putative basin, again suggesting basement structural control related to basin formation. 3) The mysterious Medusa Fossae Formation is completely enclosed within the basin margin and the units' southern contacts fall within 5 km of the same elliptical trace that bisects central Valles Marineris. 4) Chaos regions at the eastern end of Valles Marineris are wholly contained within the basin margin and suggest some kind of marginal control on their locations. 5) Valley network (channel) densities sharply increase outside the basin and are truncated by the Borealis ellipse. Integrating these and other geologic observations (still ongoing) with the newly formulated geophysical methods suggests that a single mega-impact is reemerging as a viable and perhaps preferred mechanism for dichotomy formation.

Assembly of viral particles in Xenopus oocytes: pre-surface-antigens regulate secretion of the hepatitis B viral surface envelope particle.

PubMed Central

Standring, D N; Ou, J H; Rutter, W J

1986-01-01

Infection with hepatitis B virus (HBV) is associated with the production of a viral envelope particle that contains membrane lipids, surface antigen (S), and two presurface-antigens (pre-S) comprised of the entire S moiety with approximately 55 (pre-S2) and 174 (pre-S1) additional NH2-terminal amino acids. We show here that Xenopus oocytes injected with synthetic S mRNA assemble and secrete characteristic 22-nm viral envelope particles. In contrast, pre-S1 and pre-S2 antigens are synthesized but not secreted. By coinjecting mRNAs, we found that synthesis of high levels of pre-S proteins specifically inhibits S antigen secretion. On the other hand, high levels of S synthesis can drive the secretion of small amounts of either pre-S antigen. These observations are consistent with a model for viral envelope assembly in which both S and pre-S proteins are incorporated into a multimeric particle, presumably via interactions between the S protein domains, while the pre-S amino-terminal moieties regulate the secretion of this structure. Our results indicate that Xenopus oocytes will provide a powerful system for studying the morphogenesis of simple structures of viral or cellular origin. Images PMID:3467308

On the Origins of the Task Mixing Cost in the Cuing Task-Switching Paradigm

ERIC Educational Resources Information Center

Rubin, Orit; Meiran, Nachshon

2005-01-01

Poorer performance in conditions involving task repetition within blocks of mixed tasks relative to task repetition within blocks of single task is called mixing cost (MC). In 2 experiments exploring 2 hypotheses regarding the origins of MC, participants either switched between cued shape and color tasks, or they performed them as single tasks.…

44 CFR 209.6 - Project eligibility.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Recovery Map; (iii) Were made uninhabitable (as certified by an appropriate State or local official) by the... additional amounts for pre-event fair market value. (d) Funds available under Pub. L. 106-113 (the original...

An empirical method for estimating instream pre-mining pH and dissolved Cu concentration in catchments with acidic drainage and ferricrete

USGS Publications Warehouse

Nimick, D.A.; Gurrieri, J.T.; Furniss, G.

2009-01-01

Methods for assessing natural background water quality of streams affected by historical mining are vigorously debated. An empirical method is proposed in which stream-specific estimation equations are generated from relationships between either pH or dissolved Cu concentration in stream water and the Fe/Cu concentration ratio in Fe-precipitates presently forming in the stream. The equations and Fe/Cu ratios for pre-mining deposits of alluvial ferricrete then were used to reconstruct estimated pre-mining longitudinal profiles for pH and dissolved Cu in three acidic streams in Montana, USA. Primary assumptions underlying the proposed method are that alluvial ferricretes and modern Fe-precipitates share a common origin, that the Cu content of Fe-precipitates remains constant during and after conversion to ferricrete, and that geochemical factors other than pH and dissolved Cu concentration play a lesser role in determining Fe/Cu ratios in Fe-precipitates. The method was evaluated by applying it in a fourth, naturally acidic stream unaffected by mining, where estimated pre-mining pH and Cu concentrations were similar to present-day values, and by demonstrating that inflows, particularly from unmined areas, had consistent effects on both the pre-mining and measured profiles of pH and Cu concentration. Using this method, it was estimated that mining has affected about 480 m of Daisy Creek, 1.8 km of Fisher Creek, and at least 1 km of Swift Gulch. Mean values of pH decreased by about 0.6 pH units to about 3.2 in Daisy Creek and by 1-1.5 pH units to about 3.5 in Fisher Creek. In Swift Gulch, mining appears to have decreased pH from about 5.5 to as low as 3.6. Dissolved Cu concentrations increased due to mining almost 40% in Daisy Creek to a mean of 11.7 mg/L and as much as 230% in Fisher Creek to 0.690 mg/L. Uncertainty in the fate of Cu during the conversion of Fe-precipitates to ferricrete translates to potential errors in pre-mining estimates of as much as 0.25 units for pH and 22% for dissolved Cu concentration. The method warrants further testing in other mined and unmined watersheds. Comparison of pre-mining water-quality estimates derived from the ferricrete and other methods in single watersheds would be particularly valuable. The method has potential for use in monitoring remedial efforts at mine sites with ferricrete deposits. A reasonable remediation objective might be realized when the downstream pattern of Fe/Cu ratios in modern streambed Fe-precipitates corresponds to the pattern in pre-mining alluvial ferricrete deposits along a stream valley.

Pre-fusion RSV F strongly boosts pre-fusion specific neutralizing responses in cattle pre-exposed to bovine RSV.

PubMed

Steff, Ann-Muriel; Monroe, James; Friedrich, Kristian; Chandramouli, Sumana; Nguyen, Thi Lien-Anh; Tian, Sai; Vandepaer, Sarah; Toussaint, Jean-François; Carfi, Andrea

2017-10-20

Human respiratory syncytial virus (hRSV) is responsible for serious lower respiratory tract disease in infants and in older adults, and remains an important vaccine need. RSV fusion (F) glycoprotein is a key target for neutralizing antibodies. RSV F stabilized in its pre-fusion conformation (DS-Cav1 F) induces high neutralizing antibody titers in naïve animals, but it remains unknown to what extent pre-fusion F can boost pre-existing neutralizing responses in RSV seropositive adults. We here assess DS-Cav1 F immunogenicity in seropositive cattle pre-exposed to bovine RSV, a virus closely related to hRSV. A single immunization with non-adjuvanted DS-Cav1 F strongly boosts RSV neutralizing responses, directed towards pre-fusion F-specific epitopes, whereas a post-fusion F is unable to do so. Vaccination with pre-fusion F thus represents a promising strategy for maternal immunization and for other RSV vaccine target populations such as older adults.

The lost steps of infancy: symbolization, analytic process and the growth of the self.

PubMed

Feldman, Brian

2002-07-01

In 'The Lost Steps' the Latin American novelist Alejo Carpentier describes the search by the protagonist for the origins of music among native peoples in the Amazon jungle. This metaphor can be utilized as a way of understanding the search for the pre-verbal origins of the self in analysis. The infant's experience of the tempo and rhythmicity of the mother/infant interaction and the bathing in words and sounds of the infant by the mother are at the core of the infant's development of the self. The infant observation method (Tavistock model) will be looked at as a way of developing empathy in the analyst to better understand infantile, pre-verbal states of mind. A case vignette from an adult analysis will be utilized to illustrate the theoretical concepts.

Improved Thermal-Vacuum Compatible Flat Plate Radiometric Source For System-Level Testing Of Optical Sensors

NASA Technical Reports Server (NTRS)

Schwarz, Mark A.; Kent, Craig J.; Bousquet, Robert; Brown, Steven W.

2016-01-01

In this work, we describe an improved thermal-vacuum compatible flat plate radiometric source which has been developed and utilized for the characterization and calibration of remote optical sensors. This source is unique in that it can be used in situ, in both ambient and thermal-vacuum environments, allowing it to follow the sensor throughout its testing cycle. The performance of the original flat plate radiometric source was presented at the 2009 SPIE1. Following the original efforts, design upgrades were incorporated into the source to improve both radiometric throughput and uniformity. The pre-thermal-vacuum (pre-TVAC) testing results of a spacecraft-level optical sensor with the improved flat plate illumination source, both in ambient and vacuum environments, are presented. We also briefly discuss potential FPI configuration changes in order to improve its radiometric performance.

Verification of learner’s differences by team-based learning in biochemistry classes

PubMed Central

2017-01-01

Purpose We tested the effect of team-based learning (TBL) on medical education through the second-year premedical students’ TBL scores in biochemistry classes over 5 years. Methods We analyzed the results based on test scores before and after the students’ debate. The groups of students for statistical analysis were divided as follows: group 1 comprised the top-ranked students, group 3 comprised the low-ranked students, and group 2 comprised the medium-ranked students. Therefore, group T comprised 382 students (the total number of students in group 1, 2, and 3). To calibrate the difficulty of the test, original scores were converted into standardized scores. We determined the differences of the tests using Student t-test, and the relationship between scores before, and after the TBL using linear regression tests. Results Although there was a decrease in the lowest score, group T and 3 showed a significant increase in both original and standardized scores; there was also an increase in the standardized score of group 3. There was a positive correlation between the pre- and the post-debate scores in group T, and 2. And the beta values of the pre-debate scores and “the changes between the pre- and post-debate scores” were statistically significant in both original and standardized scores. Conclusion TBL is one of the educational methods for helping students improve their grades, particularly those of low-ranked students. PMID:29207457

Clinical utility of bone scintigraphy in patients with limb pain of suspected musculoskeletal origin

PubMed Central

Ferrari, Robert

2015-01-01

Objective To determine the clinical utility of bone scintigraphy in patients with limb pain of suspected musculoskeletal origin. Material and Methods All patients aged ≥18 years who were referred for diagnosis and management of limb pain were diagnosed on the basis of history, physical examination, and investigations excluding bone scintigraphy. After the presumptive diagnosis was made (the pre-test diagnosis), all subjects underwent bone scintigraphy, or if they had a previous bone scintigram for their pain condition, the results of that scintigram were reviewed. Then, the pre-test diagnosis was reviewed in light of the bone scintigraphy findings and repeat clinical assessment as needed. The post-test diagnosis was considered either as unchanged diagnosis or changed diagnosis for the region or regions of interest. Results There were 118 females (54.8%) and 97 males (45.2%). The mean age of the entire group was 36±8.1 years (range: 18–87 years). The mean duration of the symptoms was 17.4±11.2 months (range: 1–264 months). Of the 215 subjects, 212 had a bone scintigram. Of these 212 subjects, none had a changed diagnosis. Conclusion In the evaluation of limb pain of suspected musculoskeletal origin, scintigraphy is unlikely to alter the pre-test diagnosis or affect treatment decisions after history, physical examination, and non-scintigraphic investigations. The clinical utility of scinitigraphy in this setting is low. PMID:27708914

Origin of malaria cases: a 7-year audit of global trends in indigenous and imported cases in relation to malaria elimination

PubMed Central

Velarde-Rodríguez, Mar; Van den Bergh, Rafael; Fergus, Cristin; Casellas, Aina; Sanz, Sergi; Cibulskis, Richard; Ramsay, Andrew R.; Bissell, Karen; Zachariah, Rony

2015-01-01

Background Countries in the different stages of pre-elimination, elimination, and prevention of reintroduction are required to report the number of indigenous and imported malaria cases to the World Health Organization (WHO). However, these data have not been systematically analysed at the global level. Objective For the period 2007 to 2013, we aimed to report on 1) the proportion of countries providing data on the origin of malaria cases and 2) the origin of malaria cases in countries classified as being in the stages of pre-elimination, elimination and prevention of reintroduction. Design An observational study using annual data reported through routine health information systems to the WHO Global Malaria Programme between 2007 and 2013. Results For all countries classified as being in pre-elimination, elimination, and prevention of reintroduction in the year 2013, there has been a substantial decrease in the total number of indigenous malaria cases, from more than 15,000 cases reported in 2007 to less than 4,000 cases reported in 2013. However, the total number of imported malaria cases has increased over that time period, from 5,600 imported cases in 2007 to approximately 6,800 in 2013. Conclusions Vigilant monitoring of the numbers of imported and indigenous malaria cases at national and global levels as well as appropriate strategies to target these cases will be critical to achieve malaria eradication. PMID:26449205

cis-acting intron mutations that affect the efficiency of avian retroviral RNA splicing: implication for mechanisms of control.

PubMed Central

Katz, R A; Kotler, M; Skalka, A M

1988-01-01

The full-length retroviral RNA transcript serves as (i) mRNA for the gag and pol gene products, (ii) genomic RNA that is assembled into progeny virions, and (iii) a pre-mRNA for spliced subgenomic mRNAs. Therefore, a balance of spliced and unspliced RNA is required to generate the appropriate levels of protein and RNA products for virion production. We have introduced an insertion mutation near the avian sarcoma virus env splice acceptor site that results in a significant increase in splicing to form functional env mRNA. The mutant virus is replication defective, but phenotypic revertant viruses that have acquired second-site mutations near the splice acceptor site can be isolated readily. Detailed analysis of one of these viruses revealed that a single nucleotide change at -20 from the splice acceptor site, within the original mutagenic insert, was sufficient to restore viral growth and significantly decrease splicing efficiency compared with the original mutant and wild-type viruses. Thus, minor sequence alterations near the env splice acceptor site can produce major changes in the balance of spliced and unspliced RNAs. Our results suggest a mechanism of control in which splicing is modulated by cis-acting sequences at the env splice acceptor site. Furthermore, this retroviral system provides a powerful genetic method for selection and analysis of mutations that affect splicing control. Images PMID:2839694

Multi-language translation and cross-cultural adaptation of the OARSI/OMERACT measure of intermittent and constant osteoarthritis pain (ICOAP).

PubMed

Maillefert, J F; Kloppenburg, M; Fernandes, L; Punzi, L; Günther, K-P; Martin Mola, E; Lohmander, L S; Pavelka, K; Lopez-Olivo, M A; Dougados, M; Hawker, G A

2009-10-01

To conduct a multi-language translation and cross-cultural adaptation of the Intermittent and Constant OsteoArthritis Pain (ICOAP) questionnaire for hip and knee osteoarthritis (OA). The questionnaires were translated and cross-culturally adapted in parallel, using a common protocol, into the following languages: Czech, Dutch, French (France), German, Italian, Norwegian, Spanish (Castillan), North and Central American Spanish, Swedish. The process was conducted following five steps: (1)--independent translation into the target language by two or three persons; (2)--consensus meeting to obtain a single preliminary translated version; (3)--backward translation by an independent bilingual native English speaker, blinded to the English original version; (4)--final version produced by a multidisciplinary consensus committee; (5)--pre-testing of the final version with 10-20 target-language-native hip and knee OA patients. The process could be followed and completed in all countries. Only slight differences were identified in the structure of the sentences between the original and the translated versions. A large majority of the patients felt that the questionnaire was easy to understand and complete. Only a few minor criticisms were expressed. Moreover, a majority of patients found the concepts of constant pain and pain that comes and goes to be of a great pertinence and were very happy with the distinction. The ICOAP questionnaire is now available for multi-center international studies.

Developmental toxicity testing of monoclonal antibodies: an enhanced pre- and postnatal study design option.

PubMed

Stewart, Jane

2009-09-01

For many monoclonal antibodies (mAb), the preferred species for general and reproductive safety testing is often the cynomolgus monkey. This article describes the rationale for combining the traditional "segmented" embryofetal development study with the pre- and postnatal development (PPND) study into a single "enhanced" PPND study design in the cynomolgus monkey where a single cohort of animals is exposed throughout gestation and allowed to give birth naturally. The proposed "enhanced" PPND study design evaluates all the stages of the traditional two study design using fewer animals. It also assesses the functional consequences of mid to late gestational exposure. This is of particular relevance to the risk assessment of monoclonal antibodies where fetal exposure to maternal IgG increases as pregnancy progresses and where morphologic examination of a pre-term fetus may not be adequate to reveal the presence of adverse effects on functional development of key target organs.

Physical and mental health consequences of Katrina on Vietnamese immigrants in New Orleans: a pre- and post-disaster assessment.

PubMed

Vu, Lung; Vanlandingham, Mark J

2012-06-01

We assessed the health impacts of a natural disaster upon a major immigrant community by comparing pre- and post-event measures for identical individuals. We collected standard health measures for a population-based sample of working-age Vietnamese-Americans living in New Orleans in 2005, just weeks before Katrina occurred. Near the first- and second-year anniversaries of the event, we located and re-assessed more than two-thirds of this original pre-Katrina cohort. We found statistically significant declines in health status for seven of the eight standard SF-36 subscales and for both the physical and mental health component summaries at the first anniversary of the disaster. By the second anniversary, recovery of the health dimensions assessed by these measures was substantial and significant. Most of the SF-36 mental and physical health subscales returned to their original pre-Katrina levels. Being in middle-age, being engaged in professional or self-employed occupations, being unmarried, being less acculturated, and having extensive post-Katrina property damage have statistically significant negative effects on post-Katrina health status, and several of these factors continued to impede recovery by the second anniversary. Hurricane Katrina had significant negative impacts on the mental and physical health of Vietnamese New Orleanians. Several factors present clear opportunities for targeted interventions.

Single cocaine exposure does not alter striatal pre-synaptic dopamine function in mice: an [18 F]-FDOPA PET study.

PubMed

Bonsall, David R; Kokkinou, Michelle; Veronese, Mattia; Coello, Christopher; Wells, Lisa A; Howes, Oliver D

2017-12-01

Cocaine is a recreational drug of abuse that binds to the dopamine transporter, preventing reuptake of dopamine into pre-synaptic terminals. The increased presence of synaptic dopamine results in stimulation of both pre- and post-synaptic dopamine receptors, considered an important mechanism by which cocaine elicits its reinforcing properties. However, the effects of acute cocaine administration on pre-synaptic dopamine function remain unclear. Non-invasive imaging techniques such as positron emission tomography have revealed impaired pre-synaptic dopamine function in chronic cocaine users. Similar impairments have been seen in animal studies, with microdialysis experiments indicating decreased basal dopamine release. Here we use micro positron emission tomography imaging techniques in mice to measure dopamine synthesis capacity and determine the effect of acute cocaine administration of pre-synaptic dopamine function. We show that a dose of 20 mg/kg cocaine is sufficient to elicit hyperlocomotor activity, peaking 15-20 min post treatment (p < 0.001). However, dopamine synthesis capacity in the striatum was not significantly altered by acute cocaine treatment (KiCer: 0.0097 per min vs. 0.0112 per min in vehicle controls, p > 0.05). Furthermore, expression levels of two key enzymes related to dopamine synthesis, tyrosine hydroxylase and aromatic l-amino acid decarboxylase, within the striatum of scanned mice were not significantly affected by acute cocaine pre-treatment (p > 0.05). Our findings suggest that while the regulation of dopamine synthesis and release in the striatum have been shown to change with chronic cocaine use, leading to a reduced basal tone, these adaptations to pre-synaptic dopaminergic neurons are not initiated following a single exposure to the drug. © 2017 International Society for Neurochemistry.

Interference experiment with asymmetric double slit by using 1.2-MV field emission transmission electron microscope.

PubMed

Harada, Ken; Akashi, Tetsuya; Niitsu, Kodai; Shimada, Keiko; Ono, Yoshimasa A; Shindo, Daisuke; Shinada, Hiroyuki; Mori, Shigeo

2018-01-17

Advanced electron microscopy technologies have made it possible to perform precise double-slit interference experiments. We used a 1.2-MV field emission electron microscope providing coherent electron waves and a direct detection camera system enabling single-electron detections at a sub-second exposure time. We developed a method to perform the interference experiment by using an asymmetric double-slit fabricated by a focused ion beam instrument and by operating the microscope under a "pre-Fraunhofer" condition, different from the Fraunhofer condition of conventional double-slit experiments. Here, pre-Fraunhofer condition means that each single-slit observation was performed under the Fraunhofer condition, while the double-slit observations were performed under the Fresnel condition. The interference experiments with each single slit and with the asymmetric double slit were carried out under two different electron dose conditions: high-dose for calculation of electron probability distribution and low-dose for each single electron distribution. Finally, we exemplified the distribution of single electrons by color-coding according to the above three types of experiments as a composite image.

Core body temperature during competition in the heat: National Boys' 14s Junior Championships.

PubMed

Bergeron, Michael F; McLeod, Kathryn S; Coyle, John F

2007-11-01

To examine on-court core body temperature (T(C)) and sweat loss, as well as pre- and post-play hydration status, in elite adolescent tennis players during a national championships event in a hot climate. Eight healthy, fit, young male tennis players (mean (SD) age 13.9 (0.9) years; mass 56.0 (10.7) kg; height 169.2 (14.7) cm) were evaluated during first-round singles competition at the National Boys' 14s Junior Championships in the heat (wet-bulb globe temperature (WBGT) 29.6 (0.4) degrees C). Five of those same players were also evaluated during a same-day doubles match (WBGT 31.3 (0.5) degrees C). During doubles (4.37 (0.35) h after singles), pre-play urine specific gravity (USG) (1.025 (0.002); p = 0.06) and total sweat loss (1.9 (0.2) litres; p = 0.10) tended to be higher before and during doubles, respectively, compared to singles. However, percentage change in body mass (-0.5 (0.3) %) tended to be comparatively less (p = 0.08), even though the doubles matches were generally longer (106.6 (11.2) vs 78.8 (10.9) min; p = 0.09) and the degree minutes total was greater (p = 0.04). T(C) increased (p<0.001) during singles and remained elevated, even after 10 min following the end of play. Notably, pre-play (singles) USG was strongly associated (p = 0.005) with the players' final T(C) (38.7 (0.3) degrees C) recorded at the end of singles play. Junior tennis players who begin a match not well hydrated could have progressively increasing thermal strain and a greater risk for exertional heat illness as the match advances.

Sexual and reproductive behaviour among single women aged 15-24 in eight Latin American countries: a comparative analysis.

PubMed

Ali, Mohamed M; Cleland, John

2005-03-01

A comparative analysis of exposure to sexual activity, contraceptive use, conceptions, and pregnancy resolutions among single women aged 15-24 in eight Latin American countries is presented. Using data from Demographic and Health Surveys complete contraceptive and reproductive histories are constructed for single women aged 15-24 during the 5 year period preceding each survey. Pre-marital conception rates and overall and cause-specific life-table probabilities of contraceptive discontinuation are estimated. Pregnancy outcome and intention status of births are summarized. Trends in virginity, contraceptive protection, and conception rates for five sites are documented. In all eight countries, virginity accounts for over half of all single woman-years of exposure between age 15 and 24. The percentage of sexually active time protected by contraception is less than 20% in five countries, is about 30% in Peru and 50% in Brazil and Colombia. The contribution of condoms to contraceptive protection ranges from one-tenth to one-fifth. Pre-marital conception rates among sexually active single women range from 14.1 per 100 woman-years in Nicaragua to 25.8 in Bolivia. Most pre-marital conceptions ended in live birth, and births that are legitimized by marriage or cohabitation are more likely to be wanted. In five settings, virginity has fallen over time, especially in Northeast Brazil and Colombia, and uptake of condoms has increased faster than use of other methods. Because of pervasive declines in the protective effect of virginity, conception rates among single women in Latin America are rising. Contraceptive uptake, particularly of condoms, is increasing but not sufficiently to offset the decline in virginity.

Intra-flow morphology variations within a single submarine flow: the 2005-2006 East Pacific Rise eruption

NASA Astrophysics Data System (ADS)

Fundis, A. T.; Soule, S.; Fornari, D. J.; Perfit, M. R.

2009-12-01

The 2005-2006 eruption near 9°50‧N marked the first observed repeat eruption at a mid-ocean ridge and provided a unique opportunity to deduce the emplacement dynamics of a single eruptive event. Since this new flow was documented in April 2006, a total of 41 deep-towed imaging surveys have been conducted with the Woods Hole Oceanographic Institution’s (WHOI) TowCam system. These surveys collected more than 60,000 digital color images and high-resolution (+ 10 cm) bathymetric profiles. We have analyzed the surface morphology of the flow using this data at a level of detail that has never before been possible. Pre-existing slope has been determined using bathymetric data previously collected with WHOI’s Autonomous Benthic Explorer and 30 kHz Simrad EM300 multibeam system. Our analyses quantify the spatial distributions of lava flow surface morphologies and allow us to investigate how these various morphologies relate to the physical characteristics of the ridge and dynamics of flow emplacement. Images of the 2005-2006 flow from each of the TowCam surveys were analyzed for lava flow morphology, the orientation of flow direction indicators, and for the presence of kipukas, collapse, faults and fissures. Our results support previous studies (Fornari et al., 1998, 2004; Soule et al., 2005) that suggest most of the 2005-2006 flows originated from nearly continuous fissures as discrete flow units and subsequently followed pre-existing bathymetric lows and flow channels away from the AST. These flow channels, found predominantly on the eastern flank of the ridge axis at ~9°50‧N, are primarily composed of transitions between sheet and hackly flows. The flows north of 9°53‧ and south of 9°49‧ are predominantly lobate flows with a high abundance of kipukas (<1 - 5 m diameter). The centers of lava channels that served as distribution pathways during the eruption tend to be characterized by sheet flows, while hackly flows that transition into lobate define the edges of the channels. Pillows, that are relatively rare, are concentrated at the termini of the flow lobes. The data indicate that the pre-existing slope did not influence the development of various morphologies of the 2005-2006 eruption.

A Comparison of Single-Sex and Coeducational Catholic Secondary Schooling: Evidence from the National Educational Longitudinal Study of 1988.

ERIC Educational Resources Information Center

LePore, Paul C.; Warren, John Robert

1997-01-01

Results from a comparison of single-sex and coeducational Catholic secondary schools using data from the National Educational Longitudinal Study of 1988 suggest that single-sex Catholic high schools are not especially favorable academic settings, and that any advantages of the schools only benefited boys. Pre-enrollment differences may explain…

Association between routine and standardized blood pressure measurements and left ventricular hypertrophy among patients on hemodialysis.

PubMed

Khangura, Jaspreet; Culleton, Bruce F; Manns, Braden J; Zhang, Jianguo; Barnieh, Lianne; Walsh, Michael; Klarenbach, Scott W; Tonelli, Marcello; Sarna, Magdalena; Hemmelgarn, Brenda R

2010-06-24

Left ventricular (LV) hypertrophy is common among patients on hemodialysis. While a relationship between blood pressure (BP) and LV hypertrophy has been established, it is unclear which BP measurement method is the strongest correlate of LV hypertrophy. We sought to determine agreement between various blood pressure measurement methods, as well as identify which method was the strongest correlate of LV hypertrophy among patients on hemodialysis. This was a post-hoc analysis of data from a randomized controlled trial. We evaluated the agreement between seven BP measurement methods: standardized measurement at baseline; single pre- and post-dialysis, as well as mean intra-dialytic measurement at baseline; and cumulative pre-, intra- and post-dialysis readings (an average of 12 monthly readings based on a single day per month). Agreement was assessed using Lin's concordance correlation coefficient (CCC) and the Bland Altman method. Association between BP measurement method and LV hypertrophy on baseline cardiac MRI was determined using receiver operating characteristic curves and area under the curve (AUC). Agreement between BP measurement methods in the 39 patients on hemodialysis varied considerably, from a CCC of 0.35 to 0.94, with overlapping 95% confidence intervals. Pre-dialysis measurements were the weakest predictors of LV hypertrophy while standardized, post- and inter-dialytic measurements had similar and strong (AUC 0.79 to 0.80) predictive power for LV hypertrophy. A single standardized BP has strong predictive power for LV hypertrophy and performs just as well as more resource intensive cumulative measurements, whereas pre-dialysis blood pressure measurements have the weakest predictive power for LV hypertrophy. Current guidelines, which recommend using pre-dialysis measurements, should be revisited to confirm these results.

Processing of large grain Y-123 superconductors with pre-defined porous structures

NASA Astrophysics Data System (ADS)

Sudhakar Reddy, E.; Babu, N. Hari; Shi, Y.; Cardwell, D. A.; Schmitz, G. J.

2005-02-01

Porous superconductors have inherent cooling advantages over their bulk counterparts and, as a result, are emerging as an important class of materials for practical applications. Single-domain Y-Ba-Cu-O (YBCO) foams processed with a pre-defined, open porous structure, for example, have significant potential for use as elements in resistive superconducting fault current limiters. In this case, the interconnected porosity is ideal for producing reinforced composites with improved mechanical and heat conducting properties. In this paper we describe a few simple methods for fabricating large grain YBCO superconductors with various predefined porous structures via an infiltration process from tailored, porous Y2BaCuO5 (Y-211) pre-forms manufactured by a variety of techniques, including slurry-coating of standard polyurethane foams to replicate their structure. Foams produced by this method typically have a strut thickness of a few hundred µm and pore sizes ranging from 10 to 100 pores per inch (PPI). Foams with increased strut thickness of up to millimetre dimensions can be produced by embedding organic ball spacers within the Y-211 pre-form followed by a burn-out and sintering process. Single-domain YBCO bulk materials with cellular and pre-defined 3D interconnected porosity may be produced by a similar process using tailored wax structures in Y-211 castings.

Sex, religion, and the single woman c.1950-75: the importance of a 'short' sexual revolution to the English religious crisis of the sixties.

PubMed

Brown, Callum G

2011-01-01

The English 'sexual revolution' has recently become increasingly conceived as 'long', lasting many decades, and by some historians as a gradual phenomenon, but reaching a peak with the introduction of the oral contraceptive pill in the 1960s. At the same time, the 'religious crisis' of the same decade has been attributed by some recent scholarship to liberal Christian revolt within the churches, and largely unconnected with sex. This article offers different views. First, based on the illegitimacy rate, it argues that, after a period of decline, restraint, and only minor change in the period 1946-59, the 1960s witnessed a sudden growth in pre-marital heterosexual intercourse before the pill's availability to single women, implying a cultural rather than a technological cause. Second, based on contemporary social surveys, it argues that there is clear evidence of a strong inverse correlation between levels of religious activity and levels of pre-marital sexual intercourse. Third, it argues that in the 1950s the dominant conservative Christian culture restrained single women from pre-marital sexual intercourse, but that from the early 1960s changing attitudes led to rising levels of sexual activity, led by single women, which reduced religious attitudes and Christian churchgoing, thus constituting a significant instigator of the religious crisis.

19 CFR 102.19 - NAFTA preference override.

Code of Federal Regulations, 2010 CFR

2010-04-01

... TREASURY RULES OF ORIGIN Rules of Origin § 102.19 NAFTA preference override. (a) Except in the case of... single NAFTA country, the country of origin of such good is the last NAFTA country in which that good underwent production other than minor processing, provided that a Certificate of Origin (see § 181.11 of...

A bilateral advantage for maintaining objects in visual short term memory.

PubMed

Holt, Jessica L; Delvenne, Jean-François

2015-01-01

Research has shown that attentional pre-cues can subsequently influence the transfer of information into visual short term memory (VSTM) (Schmidt, B., Vogel, E., Woodman, G., & Luck, S. (2002). Voluntary and automatic attentional control of visual working memory. Perception & Psychophysics, 64(5), 754-763). However, studies also suggest that those effects are constrained by the hemifield alignment of the pre-cues (Holt, J. L., & Delvenne, J.-F. (2014). A bilateral advantage in controlling access to visual short-term memory. Experimental Psychology, 61(2), 127-133), revealing better recall when distributed across hemifields relative to within a single hemifield (otherwise known as a bilateral field advantage). By manipulating the duration of the retention interval in a colour change detection task (1s, 3s), we investigated whether selective pre-cues can also influence how information is later maintained in VSTM. The results revealed that the pre-cues influenced the maintenance of the colours in VSTM, promoting consistent performance across retention intervals (Experiments 1 & 4). However, those effects were only shown when the pre-cues were directed to stimuli displayed across hemifields relative to stimuli within a single hemifield. Importantly, the results were not replicated when participants were required to memorise colours (Experiment 2) or locations (Experiment 3) in the absence of spatial pre-cues. Those findings strongly suggest that attentional pre-cues have a strong influence on both the transfer of information in VSTM and its subsequent maintenance, allowing bilateral items to better survive decay. Copyright © 2014 Elsevier B.V. All rights reserved.

Structural analysis of a class III preQ1 riboswitch reveals an aptamer distant from a ribosome-binding site regulated by fast dynamics

PubMed Central

Liberman, Joseph A.; Suddala, Krishna C.; Aytenfisu, Asaminew; Chan, Dalen; Belashov, Ivan A.; Salim, Mohammad; Mathews, David H.; Spitale, Robert C.; Walter, Nils G.; Wedekind, Joseph E.

2015-01-01

PreQ1-III riboswitches are newly identified RNA elements that control bacterial genes in response to preQ1 (7-aminomethyl-7-deazaguanine), a precursor to the essential hypermodified tRNA base queuosine. Although numerous riboswitches fold as H-type or HLout-type pseudoknots that integrate ligand-binding and regulatory sequences within a single folded domain, the preQ1-III riboswitch aptamer forms a HLout-type pseudoknot that does not appear to incorporate its ribosome-binding site (RBS). To understand how this unusual organization confers function, we determined the crystal structure of the class III preQ1 riboswitch from Faecalibacterium prausnitzii at 2.75 Å resolution. PreQ1 binds tightly (KD,app 6.5 ± 0.5 nM) between helices P1 and P2 of a three-way helical junction wherein the third helix, P4, projects orthogonally from the ligand-binding pocket, exposing its stem-loop to base pair with the 3′ RBS. Biochemical analysis, computational modeling, and single-molecule FRET imaging demonstrated that preQ1 enhances P4 reorientation toward P1–P2, promoting a partially nested, H-type pseudoknot in which the RBS undergoes rapid docking (kdock ∼0.6 s−1) and undocking (kundock ∼1.1 s−1). Discovery of such dynamic conformational switching provides insight into how a riboswitch with bipartite architecture uses dynamics to modulate expression platform accessibility, thus expanding the known repertoire of gene control strategies used by regulatory RNAs. PMID:26106162

Brazilian cross-cultural adaptation of “Return-to-work self-efficacy” questionnaire

PubMed Central

Silva, João Silvestre; Griep, Rosane Härter; Lagerveld, Suzanne E; Fischer, Frida Marina

2017-01-01

ABSTRACT OBJECTIVE To describe the translation and early stages of cross-cultural adaptation of the questionnaire Verwachtingen over werken (or “Return-to-work self-efficacy”) for workers in sick leave due to mental disorders, from the original in Dutch to the Brazilian Portuguese language. METHODS A panel gathering experts was formed to determine the questionnaire conceptual and item equivalence. For semantic equivalence, the Dutch-Portuguese Brazilian translations were consolidated and consensus meetings were held to structure versions of the instrument. Each version was back-translated from Brazilian Portuguese to Dutch and evaluated by one of the authors of the original version. The final version was submitted to two pre-tests for operational equivalence. RESULTS The original questionnaire in Dutch was translated twice to Brazilian Portuguese. During the process, four consensus meetings of the experts’ panel were performed to create the versions. Each version was back-translated to Dutch. One of the authors of the original questionnaire performed an evaluation on the first three versions until the definition of the final one, which was titled Expectativas sobre o trabalho (Expectations about work). Pre-tests’ participants did not reported problems to fill the questionnaire. CONCLUSIONS Results indicate that the Brazilian Portuguese cross-culturally adapted version maintains the original meaning of the questionnaire, while including characteristics peculiar to the Brazilian reality. Measurement and functional equivalence of this version must still be evaluated before its application can be recommended for workers who have been absent from work due to mental disorders. PMID:28273232

Cryogenic preamplification of a single-electron-transistor using a silicon-germanium heterojunction-bipolar-transistor

NASA Astrophysics Data System (ADS)

Curry, M. J.; England, T. D.; Bishop, N. C.; Ten-Eyck, G.; Wendt, J. R.; Pluym, T.; Lilly, M. P.; Carr, S. M.; Carroll, M. S.

2015-05-01

We examine a silicon-germanium heterojunction bipolar transistor (HBT) for cryogenic pre-amplification of a single electron transistor (SET). The SET current modulates the base current of the HBT directly. The HBT-SET circuit is immersed in liquid helium, and its frequency response from low frequency to several MHz is measured. The current gain and the noise spectrum with the HBT result in a signal-to-noise-ratio (SNR) that is a factor of 10-100 larger than without the HBT at lower frequencies. The transition frequency defined by SNR = 1 has been extended by as much as a factor of 10 compared to without the HBT amplification. The power dissipated by the HBT cryogenic pre-amplifier is approximately 5 nW to 5 μW for the investigated range of operation. The circuit is also operated in a single electron charge read-out configuration in the time-domain as a proof-of-principle demonstration of the amplification approach for single spin read-out.

Single and two-shot quantitative phase imaging using Hilbert-Huang Transform based fringe pattern analysis

NASA Astrophysics Data System (ADS)

Trusiak, Maciej; Micó, Vicente; Patorski, Krzysztof; García-Monreal, Javier; Sluzewski, Lukasz; Ferreira, Carlos

2016-08-01

In this contribution we propose two Hilbert-Huang Transform based algorithms for fast and accurate single-shot and two-shot quantitative phase imaging applicable in both on-axis and off-axis configurations. In the first scheme a single fringe pattern containing information about biological phase-sample under study is adaptively pre-filtered using empirical mode decomposition based approach. Further it is phase demodulated by the Hilbert Spiral Transform aided by the Principal Component Analysis for the local fringe orientation estimation. Orientation calculation enables closed fringes efficient analysis and can be avoided using arbitrary phase-shifted two-shot Gram-Schmidt Orthonormalization scheme aided by Hilbert-Huang Transform pre-filtering. This two-shot approach is a trade-off between single-frame and temporal phase shifting demodulation. Robustness of the proposed techniques is corroborated using experimental digital holographic microscopy studies of polystyrene micro-beads and red blood cells. Both algorithms compare favorably with the temporal phase shifting scheme which is used as a reference method.

Chemoresistance Evolution in Triple-Negative Breast Cancer Delineated by Single-Cell Sequencing.

PubMed

Kim, Charissa; Gao, Ruli; Sei, Emi; Brandt, Rachel; Hartman, Johan; Hatschek, Thomas; Crosetto, Nicola; Foukakis, Theodoros; Navin, Nicholas E

2018-05-03

Triple-negative breast cancer (TNBC) is an aggressive subtype that frequently develops resistance to chemotherapy. An unresolved question is whether resistance is caused by the selection of rare pre-existing clones or alternatively through the acquisition of new genomic aberrations. To investigate this question, we applied single-cell DNA and RNA sequencing in addition to bulk exome sequencing to profile longitudinal samples from 20 TNBC patients during neoadjuvant chemotherapy (NAC). Deep-exome sequencing identified 10 patients in which NAC led to clonal extinction and 10 patients in which clones persisted after treatment. In 8 patients, we performed a more detailed study using single-cell DNA sequencing to analyze 900 cells and single-cell RNA sequencing to analyze 6,862 cells. Our data showed that resistant genotypes were pre-existing and adaptively selected by NAC, while transcriptional profiles were acquired by reprogramming in response to chemotherapy in TNBC patients. Copyright © 2018 Elsevier Inc. All rights reserved.

The origin of transverse anisotropy in axially symmetric single molecule magnets.

PubMed

Barra, Anne-Laure; Caneschi, Andrea; Cornia, Andrea; Gatteschi, Dante; Gorini, Lapo; Heiniger, Leo-Philipp; Sessoli, Roberta; Sorace, Lorenzo

2007-09-05

Single-crystal high-frequency electron paramagnetic resonance spectroscopy has been employed on a truly axial single molecule magnet of formula [Mn(12)O(12)(tBu-CH(2)CO(2))16(CH(3)OH)4].CH(3)OH to investigate the origin of the transverse magnetic anisotropy, a crucial parameter that rules the quantum tunneling of the magnetization. The crystal structure, including the absolute structure of the crystal used for EPR experiments, has been fully determined and found to belong to I4 tetragonal space group. The angular dependence of the resonance fields in the crystallographic ab plane shows the presence of high-order tetragonal anisotropy and strong dependence on the MS sublevels with the second-highest-field transition being angular independent. This was rationalized including competing fourth- and sixth-order transverse parameters in a giant spin Hamiltonian which describes the magnetic anisotropy in the ground S = 10 spin state of the cluster. To establish the origin of these anisotropy terms, the experimental results have been further analyzed using a simplified multispin Hamiltonian which takes into account the exchange interactions and the single ion magnetic anisotropy of the Mn(III) centers. It has been possible to establish magnetostructural correlations with spin Hamiltonian parameters up to the sixth order. Transverse anisotropy in axial single molecule magnets was found to originate from the multispin nature of the system and from the breakdown of the strong exchange approximation. The tilting of the single-ion easy axes of magnetization with respect to the 4-fold molecular axis of the cluster plays the major role in determining the transverse anisotropy. Counterintuitively, the projections of the single ion easy axes on the ab plane correspond to hard axes of magnetization.

Signal Statistics and Maximum Likelihood Sequence Estimation in Intensity Modulated Fiber Optic Links Containing a Single Optical Pre-amplifier.

PubMed

Alić, Nikola; Papen, George; Saperstein, Robert; Milstein, Laurence; Fainman, Yeshaiahu

2005-06-13

Exact signal statistics for fiber-optic links containing a single optical pre-amplifier are calculated and applied to sequence estimation for electronic dispersion compensation. The performance is evaluated and compared with results based on the approximate chi-square statistics. We show that detection in existing systems based on exact statistics can be improved relative to using a chi-square distribution for realistic filter shapes. In contrast, for high-spectral efficiency systems the difference between the two approaches diminishes, and performance tends to be less dependent on the exact shape of the filter used.

Experimental and numerical investigation on laser-assisted bending of pre-loaded metal plate

NASA Astrophysics Data System (ADS)

Nowak, Zdzisław; Nowak, Marcin; Widłaszewski, Jacek; Kurp, Piotr

2018-01-01

The laser forming technique has an important disadvantage, which is the limitation of plastic deformation generated by a single laser beam pass. To increase the plastic deformation it is possible to apply external forces in the laser forming process. In this paper, we investigate the influence of external pre-loads on the laser bending of steel plate. The pre-loads investigated generate bending towards the laser beam. The thermal, elastic-plastic analysis is performed using the commercial nonlinear finite element analysis package ABAQUS. The focus of the paper is to identify how this pattern of the pre-load influence the final bend angle of the plate.

The Efficacy of Multicultural Education Training in Teacher-Credentialing Programs: A Descriptive Case Study

ERIC Educational Resources Information Center

Delk, Tricia

2017-01-01

The purpose of the qualitative descriptive embedded single case study research was to explore how multicultural curriculum and instruction in a teacher-credentialing program prepared pre-service teachers to work with diverse students. The problem was the inadequacy on the part of teacher-credentialing programs to train pre-service teachers to make…

77 FR 41428 - Healthy Lifestyles in Youth Project; Proposed Single Source Cooperative Agreement With National...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-13

... level); and (b) Pre- and post- tests to assess participant knowledge. (c) Monthly activity logs from... activity, and (c) increased ability to identify healthier food options (increase in post test scores vs... (increase in post test scores vs. pre test scores). Year Three Data (2010-2011) of AI/AN Children 1762 (839...

42 CFR 414.61 - Payment for anesthesia services furnished by a teaching CRNA.

Code of Federal Regulations, 2010 CFR

2010-10-01

... medical direction of a physician, is present with the student nurse anesthetist for the pre and post... anesthesia time in a single case with a student nurse anesthetist. (2) The teaching CRNA, who is not under... nurse anesthetists. The teaching CRNA must be present with the student nurse anesthetist for the pre and...

Developing Pre-Service Teachers' Technological Pedagogical Content Knowledge for Teaching Mathematics with the Geometer's Sketchpad through Lesson Study

ERIC Educational Resources Information Center

Meng, Chew Cheng; Sam, Lim Chap

2013-01-01

The purpose of this study was to develop pre-service secondary teachers' technological pedagogical content knowledge (TPACK) for teaching mathematics with The Geometer's Sketchpad (GSP) through Lesson Study (LS). Specifically, a single-group pretest-posttest design was employed to examine whether there was a significant difference in the…

The Effect of Food Stamp Nutrition Education on the Food Insecurity of Low-Income Women Participants

ERIC Educational Resources Information Center

Eicher-Miller, Heather A.; Mason, April C.; Abbott, Angela R.; McCabe, George P.; Boushey, Carol J.

2009-01-01

Objective: To determine the effect of Food Stamp Nutrition Education (FSNE) in Indiana on participants' food insecurity and food insufficiency. Design: A single-blind randomized design. A randomized experimental group completed 5 FSNE lessons as an intervention between a pre- and posttest, whereas a control group completed a pre- and posttest…

Development of Pre-Service Science Teachers' Awareness of Sustainable Water Use

ERIC Educational Resources Information Center

Cankaya, Cemile; Filik Iscen, Cansu

2015-01-01

Water is a vital resource for sustainable development. The aim of this research was to develop and evaluate pre-service science teachers' awareness of sustainable water usage. This research was based on a mixed method. The qualitative part of the research was based on a single group pretest-posttest experimental design, and the qualitative data…

Pre-Service Teachers Learn to Teach Geography: A Suggested Course Model

ERIC Educational Resources Information Center

Mitchell, Jerry T.

2018-01-01

How to improve geography education via teacher preparation programs has been a concern for nearly three decades, but few examples of a single, comprehensive university-level course exist. The purpose of this article is to share the model of a pre-service geography education methods course. Within the course, geography content (physical and social)…

Pre-exercise β-hydroxy-β-methylbutyrate free-acid supplementation improves work capacity recovery: a randomized, double-blinded, placebo-controlled study.

PubMed

Correia, Ana Luiza Matias; de Lima, Filipe Dinato; Bottaro, Martim; Vieira, Amilton; da Fonseca, Andrew Correa; Lima, Ricardo M

2018-02-08

The purpose of this study was to investigate the effects of a single-dose of β-hydroxy-β-methylbutyrate free acid (HMB-FA) supplementation on muscle recovery after a high-intensity exercise bout. Twenty-three trained young males were randomly assigned to receive either a single-dose supplementation of 3g of HMB-FA (n = 12; age 22.8 ± 3.0 years) or placebo (PLA; n = 11; age 22.9 ± 3.1 years). A muscle damage protocol was applied 60 minutes after supplementation, and consisted of seven sets of 20 drop jumps from a 60-cm box with 2-min rest intervals between sets. Muscle swelling, countermovement jump (CMJ), maximal voluntary isometric torque (MVIT) and work capacity (WC) were measured before, immediately after, 24, 48 and 72 hours after the exercise protocol. Muscle swelling, CMJ and MVIT changed similarly in both groups after the exercise protocol (p < 0.001), but returned to pre-exercise levels after 24 hours in both groups. WC decreased similarly in both groups after the exercise protocol (p < 0.01). For HMB-FA, WC returned to pre-exercise level 24 hours after exercise protocol. However, on PLA, WC did not return to pre-exercise level even 72 hours after the exercise protocol. In summary, a single-dose of HMB-FA supplementation improved WC recovery after a high-intensity exercise bout. However, HMB-FA did not affect the time-course of muscle swelling, MVIT and CMJ recovery.

Sam2bam: High-Performance Framework for NGS Data Preprocessing Tools

PubMed Central

Cheng, Yinhe; Tzeng, Tzy-Hwa Kathy

2016-01-01

This paper introduces a high-throughput software tool framework called sam2bam that enables users to significantly speed up pre-processing for next-generation sequencing data. The sam2bam is especially efficient on single-node multi-core large-memory systems. It can reduce the runtime of data pre-processing in marking duplicate reads on a single node system by 156–186x compared with de facto standard tools. The sam2bam consists of parallel software components that can fully utilize multiple processors, available memory, high-bandwidth storage, and hardware compression accelerators, if available. The sam2bam provides file format conversion between well-known genome file formats, from SAM to BAM, as a basic feature. Additional features such as analyzing, filtering, and converting input data are provided by using plug-in tools, e.g., duplicate marking, which can be attached to sam2bam at runtime. We demonstrated that sam2bam could significantly reduce the runtime of next generation sequencing (NGS) data pre-processing from about two hours to about one minute for a whole-exome data set on a 16-core single-node system using up to 130 GB of memory. The sam2bam could reduce the runtime of NGS data pre-processing from about 20 hours to about nine minutes for a whole-genome sequencing data set on the same system using up to 711 GB of memory. PMID:27861637

Pre-orthographic character string processing and parietal cortex: a role for visual attention in reading?

PubMed

Lobier, Muriel; Peyrin, Carole; Le Bas, Jean-François; Valdois, Sylviane

2012-07-01

The visual front-end of reading is most often associated with orthographic processing. The left ventral occipito-temporal cortex seems to be preferentially tuned for letter string and word processing. In contrast, little is known of the mechanisms responsible for pre-orthographic processing: the processing of character strings regardless of character type. While the superior parietal lobule has been shown to be involved in multiple letter processing, further data is necessary to extend these results to non-letter characters. The purpose of this study is to identify the neural correlates of pre-orthographic character string processing independently of character type. Fourteen skilled adult readers carried out multiple and single element visual categorization tasks with alphanumeric (AN) and non-alphanumeric (nAN) characters under fMRI. The role of parietal cortex in multiple element processing was further probed with a priori defined anatomical regions of interest (ROIs). Participants activated posterior parietal cortex more strongly for multiple than single element processing. ROI analyses showed that bilateral SPL/BA7 was more strongly activated for multiple than single element processing, regardless of character type. In contrast, no multiple element specific activity was found in inferior parietal lobules. These results suggests that parietal mechanisms are involved in pre-orthographic character string processing. We argue that in general, attentional mechanisms are involved in visual word recognition, as an early step of word visual analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

A multi-disciplinary approach to the origins of music: perspectives from anthropology, archaeology, cognition and behaviour.

PubMed

Morley, Iain

2014-01-01

Archaeological evidence for musical activities pre-dates even the earliest-known cave art and it remains the case that no human culture has yet been encountered that does not practise some recognisably musical activity. Yet the human abilities to make and appreciate music have been described as "amongst the most mysterious with which [we are] endowed" (Charles Darwin, 1872) and music itself as "the supreme mystery of the science of man" (Claude Levi-Strauss, 1970). Like language, music has been the subject of keen investigation across a great diversity of fields, from neuroscience and psychology, to ethnography, to studies of its structures in its own dedicated field, musicology; unlike the evolution of human language abilities, it is only recently that the origins of musical capacities have begun to receive dedicated attention. It is increasingly clear that human musical abilities are fundamentally related to other important human abilities, yet much remains mysterious about this ubiquitous human phenomenon, not least its prehistoric origins. It is evident that no single field of investigation can address the wide range of issues relevant to answering the question of music's origins. This review brings together evidence from a wide range of anthropological and human sciences, including palaeoanthropology, archaeology, neuroscience, primatology and developmental psychology, in an attempt to elucidate the nature of the foundations of music, how they have evolved, and how they are related to capabilities underlying other important human behaviours. It is proposed that at their most fundamental level musical behaviours (including both vocalisation and dance) are forms of deliberate metrically-organised gesture, and constitute a specialised use of systems dedicated to the expression and comprehension of social and emotional information between individuals. The abilities underlying these behaviours are selectively advantageous themselves; in addition, various mechanisms by which the practice of musical activities themselves could be advantageous are outlined.

Transurethral Resection of the Prostate (TURP) Versus Original and PErFecTED Prostate Artery Embolization (PAE) Due to Benign Prostatic Hyperplasia (BPH): Preliminary Results of a Single Center, Prospective, Urodynamic-Controlled Analysis

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

Carnevale, Francisco C., E-mail: fcarnevale@uol.com.br; Iscaife, Alexandre, E-mail: iscaifeboni@yahoo.com.br; Yoshinaga, Eduardo M., E-mail: dumuracca@ig.com.br

PurposeTo compare clinical and urodynamic results of transurethral resection of the prostate (TURP) to original and PErFecTED prostate artery embolization (PAE) methods for benign prostatic hyperplasia.MethodsWe prospectively randomized 30 patients to receive TURP or original PAE (oPAE) and compared them to a cohort of patients treated by PErFecTED PAE, with a minimum of 1-year follow-up. Patients were assessed for urodynamic parameters, prostate volume, international prostate symptom score (IPSS), and quality of life (QoL).ResultsAll groups were comparable for all pre-treatment parameters except bladder contractility and peak urine flow rate (Q{sub max}), both of which were significantly better in the TURP group,more » and IIEF score, which was significantly higher among PErFecTED PAE patients than TURP patients. All groups experienced significant improvement in IPSS, QoL, prostate volume, and Q{sub max}. TURP and PErFecTED PAE both resulted in significantly lower IPSS than oPAE but were not significantly different from one another. TURP resulted in significantly higher Q{sub max} and significantly smaller prostate volume than either original or PErFecTED PAE but required spinal anesthesia and hospitalization. Two patients in the oPAE group with hypocontractile bladders experienced recurrence of symptoms and were treated with TURP. In the TURP group, urinary incontinence occurred in 4/15 patients (26.7 %), rupture of the prostatic capsule in 1/15 (6.7 %), retrograde ejaculation in all patients (100 %), and one patient was readmitted for temporary bladder irrigation due to hematuria.ConclusionsTURP and PAE are both safe and effective treatments. TURP and PErFecTED PAE yield similar symptom improvement, but TURP is associated with both better urodynamic results and more adverse events.« less

A Missed Opportunity for U.S. Perinatal Human Immunodeficiency Virus Elimination: Pre-exposure Prophylaxis During Pregnancy.

PubMed

Fruhauf, Timothee; Coleman, Jenell S

2017-10-01

To estimate the proportion of women at increased risk of sexual human immunodeficiency virus (HIV) acquisition during pregnancy in a high HIV incidence urban setting to identify those who may be eligible for pre-exposure prophylaxis. We conducted a retrospective cohort study of women who received prenatal care at a large academic center in 2012. Univariable analyses and multiple logistic regression models were built to identify correlates for pre-exposure prophylaxis eligibility. Among 1,637 pregnant women, mean age was 27.6 years (SD 6.3), 59.7% were African American, and 56.0% were single. Based on the Centers for Disease Control and Prevention's guidelines, more than 10% of women were at increased risk for HIV acquisition during pregnancy and eligible for pre-exposure prophylaxis. Younger [adjusted odds ratio (OR) 0.9/1-year increase, 95% CI 0.8-0.9], single (adjusted OR 2.4, 95% CI 1.2-4.8), African American women (adjusted OR 3.3, 95% CI 1.6-6.7) with higher parity (adjusted OR 1.3/one-child increase, 95% CI 1.1-1.5), and who smoked regularly during pregnancy (adjusted OR 1.8, 95% CI 1.0-3.0) had greater odds of being eligible for pre-exposure prophylaxis at any time during pregnancy. Pregnancy is a vulnerable period during which some heterosexual women in urban settings have a high risk for HIV acquisition and stand to benefit from pre-exposure prophylaxis.

H3K9me3 demethylase Kdm4d facilitates the formation of pre-initiative complex and regulates DNA replication

PubMed Central

Wu, Rentian; Wang, Zhiquan; Zhang, Honglian; Gan, Haiyun; Zhang, Zhiguo

2017-01-01

DNA replication is tightly regulated to occur once and only once per cell cycle. How chromatin, the physiological substrate of DNA replication machinery, regulates DNA replication remains largely unknown. Here we show that histone H3 lysine 9 demethylase Kdm4d regulates DNA replication in eukaryotic cells. Depletion of Kdm4d results in defects in DNA replication, which can be rescued by the expression of H3K9M, a histone H3 mutant transgene that reverses the effect of Kdm4d on H3K9 methylation. Kdm4d interacts with replication proteins, and its recruitment to DNA replication origins depends on the two pre-replicative complex components (origin recognition complex [ORC] and minichromosome maintenance [MCM] complex). Depletion of Kdm4d impairs the recruitment of Cdc45, proliferating cell nuclear antigen (PCNA), and polymerase δ, but not ORC and MCM proteins. These results demonstrate a novel mechanism by which Kdm4d regulates DNA replication by reducing the H3K9me3 level to facilitate formation of pre-initiative complex. PMID:27679476

From the Slab to the Surface: Origin, Storage, Ascent, and Eruption of Volatile-Bearing Magmas in the Aleutian arc

NASA Astrophysics Data System (ADS)

Roman, D.; Plank, T. A.; Hauri, E. H.; Rasmussen, D. J.; Power, J. A.; Lyons, J. J.; Haney, M. M.; Werner, C. A.; Kern, C.; Lopez, T. M.; Izbekov, P. E.; Stelling, P. L.

2016-12-01

We present initial results from an integrated geochemical-geophysical study of the Unimak-Cleveland corridor of the Aleutian volcanic arc, which encompasses six volcanoes spanning 450 km of the arc that have erupted in the past 25 years with a wide range of magmatic water contents. This relatively small corridor also exhibits a range of deep and upper-crustal seismicity, apparent magma storage depths, and depths to the subducting tectonic plate. The ultimate goal of this study is to link two normally disconnected big-picture problems: 1) the deep origin of magmas and volatiles, and 2) the formation and eruption of crustal magma reservoirs, which we will do by establishing the depth(s) of crustal magma reservoirs and pre-eruptive volatile contents throughout the corridor. Our preliminary work focuses on the geographic end members Shishaldin Volcano, which last erupted in 2014-2015, and Cleveland Volcano, which last erupted in April-May of this year (2016). Both systems are persistently degassing, open-vent volcanoes whose frequent eruptions are typically characterized by minimal precursory seismicity, making eruption forecasting challenging. At Cleveland, we analyze data from a 12-station broadband seismic network deployed from August 2015-July 2016, which is complemented by two permanent seismo-acoustic stations operated by the Alaska Volcano Observatory (AVO). We also analyze tephras from recent eruptions (including 2016) and conducted ground- and helicopter-based gas emission surveys. At Shishaldin, we analyze data from the permanent AVO network, which is comprised of mainly short-period, single-component seismic stations. We also present preliminary analyses of samples of recent eruptive deposits and gas emission data. Through integration of these various datasets we present preliminary interpretations related to the origin, storage, ascent and eruption of volatile-bearing magmas at Cleveland and Shishaldin volcanoes.

A Study of a Compound Solar Eruption with Two Consecutive Erupting Magnetic Structures

NASA Astrophysics Data System (ADS)

Dhakal, Suman K.; Chintzoglou, Georgios; Zhang, Jie

2018-06-01

We report a study of a compound solar eruption that was associated with two consecutively erupting magnetic structures and correspondingly two distinct peaks, during impulsive phase, of an M-class flare (M8.5). Simultaneous multi-viewpoint observations from SDO, GOES and STEREO-A show that this compound eruption originated from two pre-existing sigmoidal magnetic structures lying along the same polarity inversion line. Observations of the associated pre-existing filaments further show that these magnetic structures are lying one on top of the other, separated by 12 Mm in height, in a so-called “double-decker” configuration. The high-lying magnetic structure became unstable and erupted first, appearing as an expanding hot channel seen at extreme ultraviolet wavelengths. About 12 minutes later, the low-lying structure also started to erupt and moved at an even faster speed compared to the high-lying one. As a result, the two erupting structures interacted and merged with each other, appearing as a single coronal mass ejection in the outer corona. We find that the double-decker configuration is likely caused by the persistent shearing motion and flux cancellation along the source active region’s strong-gradient polarity inversion line. The successive destabilization of these two separate but closely spaced magnetic structures, possibly in the form of magnetic flux ropes, led to a compound solar eruption. The study of the compound eruption provides a unique opportunity to reveal the formation process, initiation, and evolution of complex eruptive structures in solar active regions.

Correction of a Cystic Fibrosis Splicing Mutation by Antisense Oligonucleotides.

PubMed

Igreja, Susana; Clarke, Luka A; Botelho, Hugo M; Marques, Luís; Amaral, Margarida D

2016-02-01

Cystic fibrosis (CF), the most common life-threatening genetic disease in Caucasians, is caused by ∼2,000 different mutations in the CF transmembrane conductance regulator (CFTR) gene. A significant fraction of these (∼13%) affect pre-mRNA splicing for which novel therapies have been somewhat neglected. We have previously described the effect of the CFTR splicing mutation c.2657+5G>A in IVS16, showing that it originates transcripts lacking exon 16 as well as wild-type transcripts. Here, we tested an RNA-based antisense oligonucleotide (AON) strategy to correct the aberrant splicing caused by this mutation. Two AONs (AON1/2) complementary to the pre-mRNA IVS16 mutant region were designed and their effect on splicing was assessed at the RNA and protein levels, on intracellular protein localization and function. To this end, we used the 2657+5G>A mutant CFTR minigene stably expressed in HEK293 Flp-In cells that express a single copy of the transgene. RNA data from AON1-treated mutant cells show that exon 16 inclusion was almost completely restored (to 95%), also resulting in increased levels of correctly localized CFTR protein at the plasma membrane (PM) and with increased function. A novel two-color CFTR splicing reporter minigene developed here allowed the quantitative monitoring of splicing by automated microscopy localization of CFTR at the PM. The AON strategy is thus a promising therapeutic approach for the specific correction of alternative splicing. © 2015 WILEY PERIODICALS, INC.

Isotopic analysis of individual refractory metal nuggets using atom probe tomography

NASA Astrophysics Data System (ADS)

Daly, L.; Bland, P.; Schaefer, B. F.; Saxey, D. W.; Reddy, S.; Fougerouse, D.; William, R. D. A.; Forman, L. V.; Trimby, P.; La Fontaine, A.; Yang, L.; Cairney, J.; Ringer, S.

2016-12-01

Sub-micrometre metallic alloys of the highly siderophile elements, known as refractory metal nuggets (RMNs), can be found in primitive carbonaceous chondrites. There has been some suggestion that these grains may have a pre-solar origin, however their <1 µm size has meant that isotopic analysis of individual grains has not previously been possible. Atom probe microscopy has sufficient spatial resolution to quantify the isotopic compositions, across the entire mass range, of small sample volumes (<0.02 µm3) with high sensitivity and precision. We present analyses of four individual RMNs from the same refractory inclusion within the ALH 77307 meteorite. The results indicate that these RMNs have significant isotopic deviations from solar relative isotope abundances and therefore preserve a pre-solar isotopic signature. All RMNs exhibit large p-process enrichments in 98Ru and depletions in s-process 186Os. Two RMNs have a similar isotopic signature, suggesting formation in the same stellar environment. This similarity between two RMNs indicates that there may be a significant contribution of material to our solar system from a single source. The other two RMNs are isotopically dissimilar. Finally, three of the RMNs plot on a 187Re -187Os isochron from which we can derive a galactic age of 12.5 Ga ±1.8. To the best of our knowledge this is the first direct determination of the age of the Milky Way through physical analysis of non-solar material.

Variations in Paper Electrophoretic Serum Lipoprotein Patterns in Healthy Subjects

PubMed Central

Buckley, G. C.; Little, J. A.; Csima, A.

1970-01-01

The normal variations in the paper electrophoretic lipoprotein patterns in 240 healthy Canadian males and females, aged 10 to 59 years, have been described and compared with serum cholesterol and triglyceride levels. The incidence of abnormal chylomicra, beta and pre-beta lipoproteins was similar in both sexes and increased with age in both sexes. Chylomicron bands and/or pre-beta trails from the origin occurred in 4% of subjects, pre-beta bands in 27% and “abnormally” dense beta bands in 28%. Five per cent of subjects were considered to have definite hyperlipoproteinemia, another 19% had slight and 21% had questionable hyperlipoproteinemia. Fifty-five per cent were normal. PMID:5538493

Paleomagnetism and tectonics of the Jura arcuate mountain belt in France and Switzerland

NASA Astrophysics Data System (ADS)

Gehring, Andreas U.; Keller, Peter; Heller, Friedrich

1991-02-01

Goethite and hematite in ferriferous oolitic beds of Callovian age from the Jura mountains (Switzerland, France) carry either pre- and/or post-tectonic magnetization. The frequent pre-tectonic origin of goethite magnetization indicates a temperature range during formation of the arcuate Jura mountain belt below the goethite Néel temperature of about 100°C. The scatter of the pre-tectonic paleomagnetic directions ( D = 11.5° E, I = 55.5°; α95 = 4.7) which reside both in goethite and hematite, provides strong evidence that the arcuate mountain belt was shaped without significant rotation. The paleomagnetic results support tectonic thin-skinned models for the formation of the Jura mountain belt.

The pre-Newtonian meaning of the word "weight"; a comment on "Kepler and the origins of pre-Newtonian mass" [Am. J. Phys. 85, 115-123 (2017)

NASA Astrophysics Data System (ADS)

Browne, K. M.

2018-06-01

Ever since the beam balance was invented over three millennia ago, it has been used to measure what is now known as mass, but which, until the time of Newton, had always been known as "weight." Eugene Hecht recently discussed the concept of "mass" from medieval times to Newton's Principia, including the gradual change from philosophical to evidence based scientific thinking, but did not discuss the pre-Newtonian meaning of "weight" which then had the meaning of both weight and mass. The distinction between weight and mass was initiated by Kepler and completed by Newton.

Pre-seizure state identified by diffuse optical tomography

PubMed Central

Zhang, Tao; Zhou, Junli; Jiang, Ruixin; Yang, Hao; Carney, Paul R.; Jiang, Huabei

2014-01-01

In epilepsy it has been challenging to detect early changes in brain activity that occurs prior to seizure onset and to map their origin and evolution for possible intervention. Here we demonstrate using a rat model of generalized epilepsy that diffuse optical tomography (DOT) provides a unique functional neuroimaging modality for noninvasively and continuously tracking such brain activities with high spatiotemporal resolution. We detected early hemodynamic responses with heterogeneous patterns, along with intracranial electroencephalogram gamma power changes, several minutes preceding the electroencephalographic seizure onset, supporting the presence of a “pre-seizure” state. We also observed the decoupling between local hemodynamic and neural activities. We found widespread hemodynamic changes evolving from local regions of the bilateral cortex and thalamus to the entire brain, indicating that the onset of generalized seizures may originate locally rather than diffusely. Together, these findings suggest DOT represents a powerful tool for mapping early seizure onset and propagation pathways. PMID:24445927

Validity of the Eating Attitude Test among Exercisers.

PubMed

Lane, Helen J; Lane, Andrew M; Matheson, Hilary

2004-12-01

Theory testing and construct measurement are inextricably linked. To date, no published research has looked at the factorial validity of an existing eating attitude inventory for use with exercisers. The Eating Attitude Test (EAT) is a 26-item measure that yields a single index of disordered eating attitudes. The original factor analysis showed three interrelated factors: Dieting behavior (13-items), oral control (7-items), and bulimia nervosa-food preoccupation (6-items). The primary purpose of the study was to examine the factorial validity of the EAT among a sample of exercisers. The second purpose was to investigate relationships between eating attitudes scores and selected psychological constructs. In stage one, 598 regular exercisers completed the EAT. Confirmatory factor analysis (CFA) was used to test the single-factor, a three-factor model, and a four-factor model, which distinguished bulimia from food pre-occupation. CFA of the single-factor model (RCFI = 0.66, RMSEA = 0.10), the three-factor-model (RCFI = 0.74; RMSEA = 0.09) showed poor model fit. There was marginal fit for the 4-factor model (RCFI = 0.91, RMSEA = 0.06). Results indicated five-items showed poor factor loadings. After these 5-items were discarded, the three models were re-analyzed. CFA results indicated that the single-factor model (RCFI = 0.76, RMSEA = 0.10) and three-factor model (RCFI = 0.82, RMSEA = 0.08) showed poor fit. CFA results for the four-factor model showed acceptable fit indices (RCFI = 0.98, RMSEA = 0.06). Stage two explored relationships between EAT scores, mood, self-esteem, and motivational indices toward exercise in terms of self-determination, enjoyment and competence. Correlation results indicated that depressed mood scores positively correlated with bulimia and dieting scores. Further, dieting was inversely related with self-determination toward exercising. Collectively, findings suggest that a 21-item four-factor model shows promising validity coefficients among exercise participants, and that future research is needed to investigate eating attitudes among samples of exercisers. Key PointsValidity of psychometric measures should be thoroughly investigated. Researchers should not assume that a scale validation on one sample will show the same validity coefficients in a different population.The Eating Attitude Test is a commonly used scale. The present study shows a revised 21-item scale was suitable for exercisers.Researchers using the Eating Attitude Test should use subscales of Dieting, Oral control, Food pre-occupation, and Bulimia.Future research should involve qualitative techniques and interview exercise participants to explore the nature of eating attitudes.

Development of Driver/Vehicle Steering Interaction Models for Dynamic Analysis

DTIC Science & Technology

1988-12-01

Figure 5-10. The Linearized Single-Unit Vehicle Model ............................... 41 Figure 5-11. Interpretation of the Single-Unit Model...The starting point for the driver modelling research conducted under this project was a linear preview control model originally proposed by MacAdam 1...regardless of its origin, can pass at least the elementary validation test of exhibiting "cross-over model"-like- behavior in the vicinity of its

Pre_GI: a global map of ontological links between horizontally transferred genomic islands in bacterial and archaeal genomes

PubMed Central

Pierneef, Rian; Cronje, Louis; Bezuidt, Oliver; Reva, Oleg N.

2015-01-01

Abstract The Predicted Genomic Islands database (Pre_GI) is a comprehensive repository of prokaryotic genomic islands (islands, GIs) freely accessible at http://pregi.bi.up.ac.za/index.php . Pre_GI, Version 2015, catalogues 26 744 islands identified in 2407 bacterial/archaeal chromosomes and plasmids. It provides an easy-to-use interface which allows users the ability to query against the database with a variety of fields, parameters and associations. Pre_GI is constructed to be a web-resource for the analysis of ontological roads between islands and cartographic analysis of the global fluxes of mobile genetic elements through bacterial and archaeal taxonomic borders. Comparison of newly identified islands against Pre_GI presents an alternative avenue to identify their ontology, origin and relative time of acquisition. Pre_GI aims to aid research on horizontal transfer events and materials through providing data and tools for holistic investigation of migration of genes through ecological niches and taxonomic boundaries. Database URL: http://pregi.bi.up.ac.za/index.php , Version 2015 PMID:26200753

Single-nucleotide polymorphisms in the LRWD1 gene may be a genetic risk factor for Japanese patients with Sertoli cell-only syndrome.

PubMed

Miyamoto, T; Koh, E; Tsujimura, A; Miyagawa, Y; Saijo, Y; Namiki, M; Sengoku, K

2014-04-01

Genetic mechanisms have been implicated as a cause of some cases of male infertility. Recently, ten novel genes involved in human spermatogenesis, including human LRWD1, have been identified by expression microarray analysis of human testictissue. The human LRWD1 protein mediates the origin recognition complex in chromatin, which is critical for the initiation of pre-replication complex assembly in G1 and chromatin organization in post-G1 cells. The Lrwd1 gene expression is specific to the testis in mice. Therefore, we hypothesized that mutation or polymorphisms of LRWD1 participate in male infertility, especially azoospermia. To investigate whether LRWD1 gene defects are associated with azoospermia caused by SCOS and meiotic arrest (MA), mutational analysis was performed in 100 and 30 Japanese patients by direct sequencing of the coding regions, respectively. Statistical analysis was performed for patients with SCOS and MA and in 100 healthy control men. No mutations were found in LRWD1; however, three coding single-nucleotide polymorphisms (SNP1-SNP3) could be detected in the patients. The genotype and allele frequencies in SNP1 and SNP2 were notably higher in the SCOS group than in the control group (P < 0.05). These results suggest the critical role of LRWD1 in human spermatogenesis. © 2013 Blackwell Verlag GmbH.

Resolving early mesoderm diversification through single-cell expression profiling.

PubMed

Scialdone, Antonio; Tanaka, Yosuke; Jawaid, Wajid; Moignard, Victoria; Wilson, Nicola K; Macaulay, Iain C; Marioni, John C; Göttgens, Berthold

2016-07-14

In mammals, specification of the three major germ layers occurs during gastrulation, when cells ingressing through the primitive streak differentiate into the precursor cells of major organ systems. However, the molecular mechanisms underlying this process remain unclear, as numbers of gastrulating cells are very limited. In the mouse embryo at embryonic day 6.5, cells located at the junction between the extra-embryonic region and the epiblast on the posterior side of the embryo undergo an epithelial-to-mesenchymal transition and ingress through the primitive streak. Subsequently, cells migrate, either surrounding the prospective ectoderm contributing to the embryo proper, or into the extra-embryonic region to form the yolk sac, umbilical cord and placenta. Fate mapping has shown that mature tissues such as blood and heart originate from specific regions of the pre-gastrula epiblast, but the plasticity of cells within the embryo and the function of key cell-type-specific transcription factors remain unclear. Here we analyse 1,205 cells from the epiblast and nascent Flk1(+) mesoderm of gastrulating mouse embryos using single-cell RNA sequencing, representing the first transcriptome-wide in vivo view of early mesoderm formation during mammalian gastrulation. Additionally, using knockout mice, we study the function of Tal1, a key haematopoietic transcription factor, and demonstrate, contrary to previous studies performed using retrospective assays, that Tal1 knockout does not immediately bias precursor cells towards a cardiac fate.

Carbon in weathered ordinary chondrites from Roosevelt County

NASA Technical Reports Server (NTRS)

Ash, R. D.; Pillinger, C. T.

1993-01-01

A suite of Roosevelt County ordinary chondrites of known terrestrial age have been analyzed for carbon content and isotopic composition. Initial results indicate that significant carbon contamination is evident only in samples with a terrestrial age greater than 40 ka. These samples are of weathering grade D and E and contain three times more carbon than the less weathered samples. The soil in which they were preserved has a carbon content of ca. 1.5 percent. Over 200 meteorites have been recovered from a series of soil depleted areas of New Mexico and West Texas. Most have been recovered from blowouts near Clovis in Roosevelt County (RC) on the high plains of New Mexico. The mineralogical and petrologic Al effects of weathering upon these samples have been studied previously and show that the degree of weathering is largely depend ant upon the terrestrial residence time. The study was undertaken to determine the effects of prolonged exposure to the soil and climate of Roosevelt County upon ordinary chondrites in the hope that this will enable a better understanding of the problems associated with the collection of meteoritic falls. A suite of ten grade 4 to 6 H, L, and LL ordinary chondrites were analyzed for carbon content and isotopic composition.

Mission objectives for geological exploration of the Apollo 16 landing site

NASA Technical Reports Server (NTRS)

Muehlberger, W. R.; Horz, F.; Sevier, J. R.; Ulrich, G. E.

1980-01-01

The objectives of the Apollo 16 mission to delineate the nature and origin of two major physiographic units of the central lunar highlands are discussed. Surface exploration plans, specific sampling procedures, operational constraints, and suites of samples that were collected for specific local objectives are described. Pre-mission hypotheses that favored a volcanic origin for the Cayley plains as well as the Descartes mountains were proved to be wrong by the mission results, but not enough samples have been studied to draw any other definite conclusions. Two contrasting schools of thought about the origin of the Apollo fragmental impact deposits are described: one maintains that the samples are predominantly of local origin, while the other suggests more distant, basin-related sources.

Mirror-Imaged Rapid Prototype Skull Model and Pre-Molded Synthetic Scaffold to Achieve Optimal Orbital Cavity Reconstruction.

PubMed

Park, Sung Woo; Choi, Jong Woo; Koh, Kyung S; Oh, Tae Suk

2015-08-01

Reconstruction of traumatic orbital wall defects has evolved to restore the original complex anatomy with the rapidly growing use of computer-aided design and prototyping. This study evaluated a mirror-imaged rapid prototype skull model and a pre-molded synthetic scaffold for traumatic orbital wall reconstruction. A single-center retrospective review was performed of patients who underwent orbital wall reconstruction after trauma from 2012 to 2014. Patients were included by admission through the emergency department after facial trauma or by a tertiary referral for post-traumatic orbital deformity. Three-dimensional (3D) computed tomogram-based mirror-imaged reconstruction images of the orbit and an individually manufactured rapid prototype skull model by a 3D printing technique were obtained for each case. Synthetic scaffolds were anatomically pre-molded using the skull model as guide and inserted at the individual orbital defect. Postoperative complications were assessed and 3D volumetric measurements of the orbital cavity were performed. Paired samples t test was used for statistical analysis. One hundred four patients with immediate orbital defect reconstructions and 23 post-traumatic orbital deformity reconstructions were included in this study. All reconstructions were successful without immediate postoperative complications, although there were 10 cases with mild enophthalmos and 2 cases with persistent diplopia. Reoperations were performed for 2 cases of persistent diplopia and secondary touchup procedures were performed to contour soft tissue in 4 cases. Postoperative volumetric measurement of the orbital cavity showed nonsignificant volume differences between the damaged orbit and the reconstructed orbit (21.35 ± 1.93 vs 20.93 ± 2.07 cm(2); P = .98). This protocol was extended to severe cases in which more than 40% of the orbital frame was lost and combined with extensive soft tissue defects. Traumatic orbital reconstruction can be optimized and successful using an individually manufactured rapid prototype skull model and a pre-molded synthetic scaffold by computer-aid design and manufacturing. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Astrobiology and the Chemistry of the Early Solar System

NASA Technical Reports Server (NTRS)

Cook, Jamie Elsila

2011-01-01

The field of astrochemistry investigates the origin of the chemicals necessary for the formation of life. Astrochemists use remote observations, laboratory simulations, and analysis of extraterrestrial samples to understand the inventory of pre biotic chemicals present on the early Earth. Among the problems investigated by astrochemists is the origin of homo chirality in terrestrial life. Analysis of meteorites shows that they may have delivered an excess of L-amino acids to the Earth's surface, perhaps leading to homochirality.

Effects of He implantation on radiation induced segregation in Cu-Au and Ni-Si alloys

NASA Astrophysics Data System (ADS)

Iwase, A.; Rehn, L. E.; Baldo, P. M.; Funk, L.

Effects of He implantation on radiation induced segregation (RIS) in Cu-Au and Ni-Si alloys were investigated using in situ Rutherford backscattering spectrometry during simultaneous irradiation with 1.5-MeV He and low-energy (100 or 400-keV) He ions at elevated temperatures. RIS during single He ion irradiation, and the effects of pre-implantation with low-energy He ions, were also studied. RIS near the specimen surface, which was pronounced during 1.5-MeV He single-ion irradiation, was strongly reduced under low-energy He single-ion irradiation, and during simultaneous irradiation with 1.5-MeV He and low-energy He ions. A similar RIS reduction was also observed in the specimens pre-implanted with low-energy He ions. The experimental results indicate that the accumulated He atoms cause the formation of small bubbles, which provide additional recombination sites for freely migrating defects.

The Origin of Mitochondrial Cristae from Alphaproteobacteria.

PubMed

Muñoz-Gómez, Sergio A; Wideman, Jeremy G; Roger, Andrew J; Slamovits, Claudio H

2017-04-01

Mitochondria are the respiratory organelles of eukaryotes and their evolutionary history is deeply intertwined with that of eukaryotes. The compartmentalization of respiration in mitochondria occurs within cristae, whose evolutionary origin has remained unclear. Recent discoveries, however, have revived the old notion that mitochondrial cristae could have had a pre-endosymbiotic origin. Mitochondrial cristae are likely homologous to the intracytoplasmic membranes (ICMs) used by diverse alphaproteobacteria for harnessing energy. Because the Mitochondrial Contact site and Cristae Organizing System (MICOS) that controls the development of cristae evolved from a simplified version that is phylogenetically restricted to Alphaproteobacteria (alphaMICOS), ICMs most probably transformed into cristae during the endosymbiotic origin of mitochondria. This inference is supported by the sequence and structural similarities between MICOS and alphaMICOS, and the expression pattern and cellular localization of alphaMICOS. Given that cristae and ICMs develop similarly, alphaMICOS likely functions analogously to mitochondrial MICOS by culminating ICM development with the creation of tubular connections and membrane contact sites at the alphaproteobacterial envelope. Mitochondria thus inherited a pre-existing ultrastructure adapted to efficient energy transduction from their alphaproteobacterial ancestors. The widespread nature of purple bacteria among alphaproteobacteria raises the possibility that cristae evolved from photosynthetic ICMs. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

[Pre-hospital adverse events: a way to go].

PubMed

Alvarez-Ortiz, Nancy Jezzi; Aranaz Andrés, Jesús María; Gea Velázquez De Castro, María Teresa; Miralles Bueno, Juan José

2010-01-01

The occurrence of adverse events is a problem at all levels of care and creates a significant burden of morbidity and mortality. In Spain there have been significant investigations of adverse effects (AE) in hospitals and primary care, however, studies of pre-hospital care are not yet developed. The aim of this study was to determine the frequency, type, preventability, severity and impact of "pre-hospital" adverse events, which were detected in the hospitalization index and the comparing those that occurred in ambulatory and non-ambulatory care. Case Series Study, with analytical components, of a sample of subjects included in the "National study of adverse events related to hospitalization (ENEAS). Qualitative data are presented as proportions with confidence intervals. For comparative analysis of qualitative data, we used the chi-square test. Of a total of 5624 patients, 2.3% (N=131) ((95%)CI: 1.94-2.72) had an AE that occurred prior to hospitalization or "pre-hospital", and 40.5% of these (N=53) ((95%)CI: 32.05-48.86) were preventable. In 44 patients the AE had its origin in ambulatory care and 85 patients in non-ambulatory care. The characteristic of patients with ambulatory AE are men and older women (median 76 years) who consulted for medical problems (84.1%) and the AE were related to medication in 77.8%. The characteristic of patients with non-ambulatory AE, were men (median 73 years), consulting for medical and surgical problems (44,7-55,3%) and the EA is related to medications, infections and procedures. The characteristics of patients with AE and undesirable effects that occurred during pre-hospitalization period depended on whether they originated during ambulatory care or non-ambulatory care. Therefore prevention strategies should take these differences into account. Copyright 2009 SECA. Published by Elsevier Espana. All rights reserved.

Electrooxidation as the anaerobic pre-treatment of fats: oleate conversion using RuO2 and IrO2 based anodes.

PubMed

Gonçalves, M; Alves, M M; Correia, J P; Marques, I P

2008-11-01

Electrochemical treatment of oleate using RuO2 and IrO2 type dimensionally stable anodes in alkaline medium was performed to develop a feasible anaerobic pre-treatment of fatty effluents. The results showed that the pre-treated solutions over RuO2 were faster degraded by anaerobic consortium than the raw oleate solutions or the electrolysed solutions using IrO2. In batch experiments carried out with pre-treated solutions over RuO2 (100-500mg/L), no lag phases were observed before the methane production onset. On the other hand, raw oleate and pre-treated oleate over IrO2 had originated lag phases of 0-140 and 0-210h, respectively. This study demonstrated that it is advantageous to apply the electrochemical treatment carried out on the RuO2 type DSA in order to achieve a faster biodegradation of lipid-containing effluent and consequently to obtain a faster methane production.

The Impact of Anxious and Calm Emotional States on Color Usage in Pre-Drawn Mandalas

ERIC Educational Resources Information Center

Kersten, Andrea; van der Vennet, Renee

2010-01-01

The purpose of this single-subject experiment was to test whether a link exists between emotional state and color usage in a common art therapy technique. The researchers hypothesized that when coloring a pre-drawn mandala, participants would choose warm colors when they were anxious and cool colors when they were calm. The non-random sample…

Distance Coaching for Pre-Service Teachers: Impacts on Children's Functional Communication in Inclusive Preschool Classrooms

ERIC Educational Resources Information Center

Storie, Sloan; Coogle, Christan Grygas; Rahn, Naomi; Ottley, Jennifer Riggie

2017-01-01

This article reports the results of a post hoc analysis of child data from a single-case multiple-probe study of pre-service teachers' use of communication strategies before, while, and after receiving distance coaching. Data were analyzed for the number of functional communication utterances used by groups of preschool children with and without…

Historical Novels: Engaging Student Teachers in K-10 History Pre-Service Units

ERIC Educational Resources Information Center

Rodwell, Grant

2010-01-01

This paper aims to illustrate how the historical novel may be used as an engaging teacher/learning strategy for undergraduate student teachers in pre-service teacher education units, the vast majority of which simply provide for a single 10-credit point unit in order to prepare student teachers for the classroom. First, this paper will argue the…

Impact of thermal pretreatment and MSW origin on composition and hydrolysability in a sugar platform biorefinery

NASA Astrophysics Data System (ADS)

Vaurs, L. P.; Heaven, S.; Banks, C. J.

2018-03-01

Municipal solid waste (MSW) is a widely available large volume source of lignocellulosic material containing a waste paper/cardboard mixture which can be converted into fermentable sugars via cellulolytic enzyme hydrolysis in a sugar platform biorefinery. Thermal pretreatments are generally applied to MSW to facilitate the extraction of the lignocellulosic material from recyclable materials (plastics, metals etc.) and improve the paper pulp conversion to sugars. Applying high temperature might enhance food waste solubilisation but may collapse cellulose fibre decreasing its hydrolysability. Low temperature pre-treatment will reduce the energy demand but might result in highly contaminated pulp. Preliminary results showed that the enzymatic hydrolysis performances were dependent on the MSW origins. Using 8 different samples, the impact of thermal pretreatment and MSW origin on pulp composition and hydrolysability was assessed in this work. Low pre-treatment temperature produced pulp which contained less lignocellulosic material but which hydrolysed to a higher degree than MSW treated at high temperatures. High temperature pre-treatment could have exposed more of the inhibiting lignin to cellulase. This information would have a significant economic impact on a commercial plant as expensive autoclave could be advantageously replaced by a cheaper process. Glucan conversions were also found to vary depending on the region, the recycling rate possibly because of the lower recycling rate resulting in the use of less paper additive in the material or the difference in paper production technology (chemical VS mechanical pulping). This could also be explained by the differences in paper composition.

Structural analysis of a class III preQ 1 riboswitch reveals an aptamer distant from a ribosome-binding site regulated by fast dynamics

DOE PAGES

Liberman, Joseph A.; Suddala, Krishna C.; Aytenfisu, Asaminew; ...

2015-06-23

PreQ 1-III riboswitches are newly identified RNA elements that control bacterial genes in response to preQ 1 (7-aminomethyl-7-deazaguanine), a precursor to the essential hypermodified tRNA base queuosine. Although numerous riboswitches fold as H-type or HL out-type pseudoknots that integrate ligand-binding and regulatory sequences within a single folded domain, the preQ 1-III riboswitch aptamer forms a HL out-type pseudoknot that does not appear to incorporate its ribosome-binding site (RBS). To understand how this unusual organization confers function, in this paper we determined the crystal structure of the class III preQ 1 riboswitch from Faecalibacterium prausnitzii at 2.75 Å resolution. PreQ 1more » binds tightly (K D,app 6.5 ± 0.5 nM) between helices P1 and P2 of a three-way helical junction wherein the third helix, P4, projects orthogonally from the ligand-binding pocket, exposing its stem-loop to base pair with the 3' RBS. Biochemical analysis, computational modeling, and single-molecule FRET imaging demonstrated that preQ 1 enhances P4 reorientation toward P1–P2, promoting a partially nested, H-type pseudoknot in which the RBS undergoes rapid docking (k dock ~0.6 s -1) and undocking (k undock ~1.1 s -1). Finally, discovery of such dynamic conformational switching provides insight into how a riboswitch with bipartite architecture uses dynamics to modulate expression platform accessibility, thus expanding the known repertoire of gene control strategies used by regulatory RNAs.« less

Spatiotemporal coupling and decoupling of gene transcription with DNA replication origins during embryogenesis in C. elegans

PubMed Central

Pourkarimi, Ehsan; Bellush, James M; Whitehouse, Iestyn

2016-01-01

The primary task of developing embryos is genome replication, yet how DNA replication is integrated with the profound cellular changes that occur through development is largely unknown. Using an approach to map DNA replication at high resolution in C. elegans, we show that replication origins are marked with specific histone modifications that define gene enhancers. We demonstrate that the level of enhancer associated modifications scale with the efficiency at which the origin is utilized. By mapping replication origins at different developmental stages, we show that the positions and activity of origins is largely invariant through embryogenesis. Contrary to expectation, we find that replication origins are specified prior to the broad onset of zygotic transcription, yet when transcription initiates it does so in close proximity to the pre-defined replication origins. Transcription and DNA replication origins are correlated, but the association breaks down when embryonic cell division ceases. Collectively, our data indicate that replication origins are fundamental organizers and regulators of gene activity through embryonic development. DOI: http://dx.doi.org/10.7554/eLife.21728.001 PMID:28009254

Blocking monocyte transmigration in in vitro system by an anti-CD99 human antibody in single chain fragment variable (scFv) format. Efficient large scale purification of biological active scFv from inclusion bodies in E. coli expression system

PubMed Central

Moricoli, Diego; Muller, William A.; Carbonella, Damiano Cosimo; Balducci, Maria Cristina; Dominici, Sabrina; Fiori, Valentina; Watson, Richard; Weber, Evan; Cianfriglia, Maurizio; Scotlandi, Katia; Magnani, Mauro

2015-01-01

Migration of leukocytes into a site of inflammation involves several steps mediated by various families of adhesion molecules. CD99 play a significant role in transendothelial migration (TEM) of leukocytes. Inhibition of TEM by specific monoclonal antibody (mAb) can provide a potent therapeutic approach to treating inflammatory conditions. However, the therapeutic utilization of whole IgG can lead to an inappropriate activation of Fc receptor-expressing cells inducing serious adverse side effects due to cytokine release. In this regard, specific recombinant antibody in single chain variable fragments (scFvs) originated by phage library may offer a solution by affecting TEM function in a safe clinical context. However, this consideration requires large scale production of functional scFv antibodies under GMP conditions and hence, the absence of toxic reagents utilized for the solubilization and refolding steps of inclusion bodies that may discourage industrial application of these antibody fragments. In order to apply the scFv anti-CD99 named C7A in a clinical setting we herein describe an efficient and large scale production of the antibody fragments expressed in E.coli as insoluble protein avoiding gel filtration chromatography approach, and laborious refolding step pre- and post-purification. Using differential salt elution which is a simple, reproducible and effective procedure we are able to separate scFv in monomer format from aggregates. The purified scFv antibody C7A exhibits inhibitory activity comparable to an antagonistic conventional mAb, thus providing an excellent agent for blocking CD99 signalling. Thanks to the original purification protocol that can be extended to other scFvs that are expressed as inclusion bodies in bacterial systems, the scFv anti-CD99 C7A herein described represents the first step towards the construction of new antibody therapeutic. PMID:24798881

Thellier's Betes Noires and how to Recognize Them

NASA Astrophysics Data System (ADS)

Dunlop, D. J.

2007-12-01

When Emile Thellier invented his classic paleointensity determination method, he made it quite clear that it applied only to NRMs which had originated as TRMs carried by non-interacting single-domain grains. Baked clays and bricks satisfied his stringent requirements but volcanic rocks were tested and rejected as unsuitable. While most paleomagnetists would regard Thellier's stance as unduly rigid, it certainly would help improve the usual dismal success rate in paleointensity studies if at the outset one could recognize and discard Thellierś betes noires: (1) NRMs of non-TRM origin, such as CRMs and TCRMs, which are particularly insidious because they may yield linear Arai plots with the wrong slope; (2) interacting grains, which compromise the independence of non-overlapping pTRMs; (3) grains larger than single-domain size with non-reciprocal blocking and unblocking. Pre-screening based on physical mechanisms would also be an improvement compared to relying solely on reliability parameters and checks. These are effective in detecting laboratory alteration of a rock but less so in filtering out samples which behave reversibly, yet are flawed recorders of the paleofield. FORC diagrams combine analysis of coercivity distribution, strength of interactions, and basic domain state. Their effectiveness in weeding out magnetic deviants has been demonstrated by Carvallo et al. (JGR 111, B12103, 2006). However, the CRM/TCRM problem remains severe. Almost all CRMs measured by Draeger et al. (GJI 166, 12-32, 2006) had ideal Arai plots but field intensity values were in error by as much as a factor 2. Unfortunately CRM/TCRM is not easily diagnosed in individual samples, and we are driven to reconsider Thellier's dictum: don't take risks by using rocks whose NRM could be other than TRM. Unfortunately this includes many attractive candidates, volcanic glasses, baked contacts and most metamorphic rocks among them. A crude approach might be to reject those samples in a collection whose NRM/SIRM ratios are conspicuously low compared to the average, although choosing the threshold for rejection would be highly subjective.

Magnetospheric Accretion in Close Pre-main-sequence Binaries

NASA Astrophysics Data System (ADS)

Ardila, David R.; Jonhs-Krull, Christopher; Herczeg, Gregory J.; Mathieu, Robert D.; Quijano-Vodniza, Alberto

2015-10-01

The transfer of matter between a circumbinary disk and a young binary system remains poorly understood, obscuring the interpretation of accretion indicators. To explore the behavior of these indicators in multiple systems, we have performed the first systematic time-domain study of young binaries in the ultraviolet. We obtained far- and near-ultraviolet HST/COS spectra of the young spectroscopic binaries DQ Tau and UZ Tau E. Here we focus on the continuum from 2800 to 3200 Å and on the C iv doublet (λλ1548.19, 1550.77 Å) as accretion diagnostics. Each system was observed over three or four consecutive binary orbits, at phases ∼0, 0.2, 0.5, and 0.7. Those observations are complemented by ground-based U-band measurements. Contrary to model predictions, we do not detect any clear correlation between accretion luminosity and phase. Further, we do not detect any correlation between C iv flux and phase. For both stars the appearance of the C iv line is similar to that of single Classical T Tauri Stars (CTTSs), despite the lack of stable long-lived circumstellar disks. However, unlike the case in single CTTSs, the narrow and broad components of the C iv lines are uncorrelated, and we argue that the narrow component is powered by processes other than accretion, such as flares in the stellar magnetospheres and/or enhanced activity in the upper atmosphere. We find that both stars contribute equally to the narrow component C iv flux in DQ Tau, but the primary dominates the narrow component C iv emission in UZ Tau E. The C iv broad component flux is correlated with other accretion indicators, suggesting an accretion origin. However, the line is blueshifted, which is inconsistent with its origin in an infall flow close to the star. It is possible that the complicated geometry of the region, as well as turbulence in the shock region, are responsible for the blueshifted line profiles.

Pre-microRNA and Mature microRNA in Human Mitochondria

PubMed Central

Barrey, Eric; Saint-Auret, Gaelle; Bonnamy, Blandine; Damas, Dominique; Boyer, Orane; Gidrol, Xavier

2011-01-01

Background Because of the central functions of the mitochondria in providing metabolic energy and initiating apoptosis on one hand and the role that microRNA (miRNA) play in gene expression, we hypothesized that some miRNA could be present in the mitochondria for post-transcriptomic regulation by RNA interference. We intend to identify miRNA localized in the mitochondria isolated from human skeletal primary muscular cells. Methodology/Principal Findings To investigate the potential origin of mitochondrial miRNA, we in-silico searched for microRNA candidates in the mtDNA. Twenty five human pre-miRNA and 33 miRNA aligments (E-value<0.1) were found in the reference mitochondrial sequence and some of the best candidates were chosen for a co-localization test. In situ hybridization of pre-mir-302a, pre-let-7b and mir-365, using specific labelled locked nucleic acids and confocal microscopy, demonstrated that these miRNA were localized in mitochondria of human myoblasts. Total RNA was extracted from enriched mitochondria isolated by an immunomagnetic method from a culture of human myotubes. The detection of 742 human miRNA (miRBase) were monitored by RT-qPCR at three increasing mtRNA inputs. Forty six miRNA were significantly expressed (2nd derivative method Cp>35) for the smallest RNA input concentration and 204 miRNA for the maximum RNA input concentration. In silico analysis predicted 80 putative miRNA target sites in the mitochondrial genome (E-value<0.05). Conclusions/Significance The present study experimentally demonstrated for the first time the presence of pre-miRNA and miRNA in the human mitochondria isolated from skeletal muscular cells. A set of miRNA were significantly detected in mitochondria fraction. The origin of these pre-miRNA and miRNA should be further investigate to determine if they are imported from the cytosol and/or if they are partially processed in the mitochondria. PMID:21637849

Releasing pre-adoption birth records: the impact of Oregon's experience on its vital records department.

PubMed

Barfield, Wanda D; Rhodes, Julia C; Kohn, Melvin A; Hedberg, Katrina; Schoendorf, Kenneth C

2002-01-01

In November 1998, Oregon voters passed Ballot Measure 58, which allowed Oregon adoptees > or = 21 years of age access to their original birth records, which are sealed at adoption. The objective of this study was to evaluate the impact of the measure on the Oregon Health Division (since renamed Oregon Health Services) by assessing procedures used and resources needed after implementation of Measure 58. Vital records employees were interviewed about processing, storage, and archive retrieval procedures for pre-adoption birth records before, during, and after the implementation of Measure 58 and the effect on their usual workload. Personnel time, space, and fiscal resources used to process requests for pre-adoption records were also calculated. The Oregon Health Division began to receive requests from adoptees immediately following the passage of Measure 58 in November 1998, but due to legal challenges, they could not be processed until May 31, 2000. From June 2, 2000, through October 20, 2000, 12 staff members and two supervisors issued more than 4,700 pre-adoption birth records while also processing their normal workload, which averages more than 135,400 vital record orders annually. Due to the need for retrieval from archives, requests for pre-adoption birth records were estimated to take 75 hours to process vs. 2-3 minutes for standard requests. Each batch of approximately 75 pre-adoption birth records required approximately 12.5 person-hours from vital records staff and 3-4 person-hours from archive personnel; in addition, supervisors spent time responding to incomplete orders, informing the public and the media, and responding to concerns of adoptees, birth parents, and adoptive parents. Fewer than 1% of requests went unfilled. Implementation of Measure 58 utilized substantial resources of the Oregon Health Division. States contemplating similar legislation should consider increasing personnel and resources, preparing for intense public and media interest, and reorganizing the storage of adoptees' original birth records so they are easily retrieved.

Merkel cell carcinoma: is this a true carcinoma?

PubMed

Jankowski, Marek; Kopinski, Piotr; Schwartz, Robert; Czajkowski, Rafal

2014-11-01

Recent years have brought an enhanced understanding of Merkel cell carcinoma (MCC) biology, especially with regard to the Merkel cell polyoma virus as a causative agent. Differences between Merkel cell polyomavirus-positive and Merkel cell polyomavirus-negative MCC in morphology; gene expression, miRNA profiles and prognosis have been reported. Origin of MCC is controversial. Presence of neurosecretory granules has suggested that these carcinomas originate from one of the neurocrest derivatives, most probably Merkel cells; the name Merkel cell carcinoma is now widely accepted. Expression of PGP 9.5, chromogranin A and several neuropeptides, initially regarded as specific markers for neural and neuroendocrine cells, has recently been shown in a subset of lymphomas. MCC commonly expresses terminal deoxynucleotidyl transferase and PAX5. Their co-expression under physiologic circumstances is restricted to pro/pre-B cells and pre-B cells. These findings lead to the hypothesis by zur Hausen et al. that MCC originates from early B cells. This review was intended to critically appraise zur Hausen's hypothesis and discuss the possibility that MCC is a heterogenous entity with distinct subtypes. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Origin of mitochondria by intracellular enslavement of a photosynthetic purple bacterium

PubMed Central

Cavalier-Smith, Thomas

2006-01-01

Mitochondria originated by permanent enslavement of purple non-sulphur bacteria. These endosymbionts became organelles through the origin of complex protein-import machinery and insertion into their inner membranes of protein carriers for extracting energy for the host. A chicken-and-egg problem exists: selective advantages for evolving import machinery were absent until inner membrane carriers were present, but this very machinery is now required for carrier insertion. I argue here that this problem was probably circumvented by conversion of the symbiont protein-export machinery into protein-import machinery, in three phases. I suggest that the first carrier entered the periplasmic space via pre-existing β-barrel proteins in the bacterial outer membrane that later became Tom40, and inserted into the inner membrane probably helped by a pre-existing inner membrane protein, thereby immediately providing the protoeukaryote host with photosynthesate. This would have created a powerful selective advantage for evolving more efficient carrier import by inserting Tom70 receptors. Massive gene transfer to the nucleus inevitably occurred by mutation pressure. Finally, pressure from harmful, non-selected gene transfer to the nucleus probably caused evolution of the presequence mechanism, and photosynthesis was lost. PMID:16822756

SU-E-J-76: CBCT Reconstruction of a Full Couch Using Rigid Registration and Pre-Scanned Couch Image and Its Clinical Application

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

Hu, E; Lasio, G; Lee, M

Purpose: Only a part of a treatment couch is reconstructed in CBCT due to the limited field of view (FOV). This often generates inaccurate results in the delivered dose evaluation with CBCT and more noise in the CBCT reconstruction. Full reconstruction of the couch at treatment setup can be used for more accurate exit beam dosimetry. The goal of this study is to develop a method to reconstruct a full treatment couch using a pre-scanned couch image and rigid registration. Methods: A full couch (Exact Couch, Varian) model image was reconstructed by rigidly registering and combining two sets of partialmore » CBCT images. The full couch model includes three parts: two side rails and a couch top. A patient CBCT was reconstructed with reconstruction grid size larger than the physical field of view to include the full couch. The image quality of the couch is not good due to data truncation, but good enough to allow rigid registration of the couch. A composite CBCT image of the patient plus couch has been generated from the original reconstruction by replacing couch portion with the pre-acquired model couch, rigidly registered to the original scan. We evaluated the clinical usefulness of this method by comparing treatment plans generated on the original and on the modified scans. Results: The full couch model could be attached to a patient CBCT image set via rigid image registration. Plan DVHs showed 1∼2% difference between plans with and without full couch modeling. Conclusion: The proposed method generated a full treatment couch CBCT model, which can be successfully registered to the original patient image. This method was also shown to be useful in generating more accurate dose distributions, by lowering 1∼2% dose in PTV and a few other critical organs. Part of this study is supported by NIH R01CA133539.« less

Hydrologic response of catchments to precipitation: Quantification of mechanical carriers and origins of water

NASA Astrophysics Data System (ADS)

Park, Y.-J.; Sudicky, E. A.; Brookfield, A. E.; Jones, J. P.

2011-12-01

Precipitation-induced overland and groundwater flow and mixing processes are quantified to analyze the temporal (event and pre-event water) and spatial (groundwater discharge and overland runoff) origins of water entering a stream. Using a distributed-parameter control volume finite-element simulator that can simultaneously solve the fully coupled partial differential equations describing 2-D Manning and 3-D Darcian flow and advective-dispersive transport, mechanical flow (driven by hydraulic potential) and tracer-based hydrograph separation (driven by dispersive mixing as well as mechanical flow) are simulated in response to precipitation events in two cross sections oriented parallel and perpendicular to a stream. The results indicate that as precipitation becomes more intense, the subsurface mechanical flow contributions tend to become less significant relative to the total pre-event stream discharge. Hydrodynamic mixing can play an important role in enhancing pre-event tracer signals in the stream. This implies that temporally tagged chemical signals introduced into surface-subsurface flow systems from precipitation may not be strong enough to detect the changes in the subsurface flow system. It is concluded that diffusive/dispersive mixing, capillary fringe groundwater ridging, and macropore flow can influence the temporal sources of water in the stream, but any sole mechanism may not fully explain the strong pre-event water discharge. Further investigations of the influence of heterogeneity, residence time, geomorphology, and root zone processes are required to confirm the conclusions of this study.

Hydrologic response of catchments to precipitation: Quantification of mechanical carriers and origins of water

USGS Publications Warehouse

Park, Y.-J.; Sudicky, E.A.; Brookfield, A.E.; Jones, J.P.

2011-01-01

Precipitation-induced overland and groundwater flow and mixing processes are quantified to analyze the temporal (event and pre-event water) and spatial (groundwater discharge and overland runoff) origins of water entering a stream. Using a distributed-parameter control volume finite-element simulator that can simultaneously solve the fully coupled partial differential equations describing 2-D Manning and 3-D Darcian flow and advective-dispersive transport, mechanical flow (driven by hydraulic potential) and tracer-based hydrograph separation (driven by dispersive mixing as well as mechanical flow) are simulated in response to precipitation events in two cross sections oriented parallel and perpendicular to a stream. The results indicate that as precipitation becomes more intense, the subsurface mechanical flow contributions tend to become less significant relative to the total pre-event stream discharge. Hydrodynamic mixing can play an important role in enhancing pre-event tracer signals in the stream. This implies that temporally tagged chemical signals introduced into surface-subsurface flow systems from precipitation may not be strong enough to detect the changes in the subsurface flow system. It is concluded that diffusive/dispersive mixing, capillary fringe groundwater ridging, and macropore flow can influence the temporal sources of water in the stream, but any sole mechanism may not fully explain the strong pre-event water discharge. Further investigations of the influence of heterogeneity, residence time, geomorphology, and root zone processes are required to confirm the conclusions of this study. Copyright 2011 by the American Geophysical Union.

Finite element analysis of the axial stiffness of a ball screw

NASA Astrophysics Data System (ADS)

Zhou, L.-X.; Li, P.-Y.

2018-06-01

The ball screw was developed for high speed and high precision operation; therefore, increasingly greater demands have been placed on the stiffness of the ball screw. Firstly, ANSYS software was used to compare the axial stiffness of a single-nut and single-arc ball screw and a single-nut and double-arc ball screw when the spiral angle is not considered. On this basis, the model of a single-nut ball screw was established taking into consideration the spiral lead angle, and then the variations in displacement and stiffness when the ball screw pair was subjected to an axial force were determined. The axial contact stiffness of the double-nut ball screw pair, subject to a pre-tightening force, was analyzed, according to the above-mentioned steps. The simulation results demonstrated that under the same working conditions, the stiffness of the double-arc ball screw was larger by between 5∼100 N/um than that of the single-arc ball screw. The spiral lead angle increased the axial stiffness of the ball screw pair, and the axial stiffness of the double-nut ball screw pair subject to a pre-tightening force was larger by between 790∼1360 N/um than that of the axial stiffness of the single-nut ball screw pair.

Sensory exploitation and sexual conflict

PubMed Central

Arnqvist, Göran

2006-01-01

Much of the literature on male–female coevolution concerns the processes by which male traits and female preferences for these can coevolve and be maintained by selection. There has been less explicit focus on the origin of male traits and female preferences. Here, I argue that it is important to distinguish origin from subsequent coevolution and that insights into the origin can help us appreciate the relative roles of various coevolutionary processes for the evolution of diversity in sexual dimorphism. I delineate four distinct scenarios for the origin of male traits and female preferences that build on past contributions, two of which are based on pre-existing variation in quality indicators among males and two on exploitation of pre-existing sensory biases among females. Recent empirical research, and theoretical models, suggest that origin by sensory exploitation has been widespread. I argue that this points to a key, but perhaps transient, role for sexually antagonistic coevolution (SAC) in the subsequent evolutionary elaboration of sexual traits, because (i) sensory exploitation is often likely to be initially costly for individuals of the exploited sex and (ii) the subsequent evolution of resistance to sensory exploitation should often be associated with costs due to selective constraints. A review of a few case studies is used to illustrate these points. Empirical data directly relevant to the costs of being sensory exploited and the costs of evolving resistance is largely lacking, and I stress that such data would help determining the general importance of sexual conflict and SAC for the evolution of sexual dimorphism. PMID:16612895

Cardiac arrhythmias during exercise testing in healthy men.

NASA Technical Reports Server (NTRS)

Beard, E. F.; Owen, C. A.

1973-01-01

Clinically healthy male executives who participate in a long-term physical conditioning program have demonstrated cardiac arrhythmia during and after periodic ergometric testing at submaximal and maximal levels. In 1,385 tests on 248 subjects, it was found that 34% of subjects demonstrated an arrhythmia at some time and 13% of subjects developed arrhythmia on more than one test. Premature systoles of ventricular origin were most common, but premature systoles of atrial origin, premature systoles of junctional origin, paroxysmal atrial tachycardia, atrioventricular block, wandering pacemaker, and pre-excitation were also seen. Careful post-test monitoring and pulse rate regulated training sessions are suggested for such programs.

Electrochemical Quantification of Extracellular Local H2O2 Kinetics Originating from Single Cells.

PubMed

Bozem, Monika; Knapp, Phillip; Mirčeski, Valentin; Slowik, Ewa J; Bogeski, Ivan; Kappl, Reinhard; Heinemann, Christian; Hoth, Markus

2017-05-15

H 2 O 2 is produced by all eukaryotic cells under physiological and pathological conditions. Due to its enormous relevance for cell signaling at low concentrations and antipathogenic function at high concentrations, precise quantification of extracellular local H 2 O 2 concentrations ([H 2 O 2 ]) originating from single cells is required. Using a scanning electrochemical microscope and bare platinum disk ultramicroelectrodes, we established sensitive long-term measurements of extracellular [H 2 O 2 ] kinetics originating from single primary human monocytes (MCs) ex vivo. For the electrochemical techniques square wave voltammetry, cyclic and linear scan voltammetry, and chronoamperometry, detection limits for [H 2 O 2 ] were determined to be 5, 50, and 500 nM, respectively. Following phorbol ester stimulation, local [H 2 O 2 ] 5-8 μm above a single MC increased by 3.4 nM/s within the first 10 min before reaching a plateau. After extracellular addition of H 2 O 2 to an unstimulated MC, the local [H 2 O 2 ] decreased on average by 4.2 nM/s due to degradation processes of the cell. Using the scanning mode of the setup, we found that H 2 O 2 is evenly distributed around the producing cell and can still be detected up to 30 μm away from the cell. The electrochemical single-cell measurements were validated in MC populations using electron spin resonance spectroscopy and the Amplex ® UltraRed assay. Innovation and Conclusion: We demonstrate a highly sensitive, spatially, and temporally resolved electrochemical approach to monitor dynamics of production and degradation processes for H 2 O 2 separately. Local extracellular [H 2 O 2 ] kinetics originating from single cells is quantified in real time. Antioxid. Redox Signal. 00, 000-000.