A review of an attempt to create shatter cones with magnetic flyer plate technology

NASA Technical Reports Server (NTRS)

Linnerud, H. J.

1981-01-01

The feasibility of creating shatter cones in a controlled laboratory environment is discussed. Magnetic flyer plate technology, which generates high amplitude shock waves in test materials is discribed. Considerable sample shear and break up was observed, however, no shatter cones are found in the tested samples.

A Meteorite Fragment Trapped Between Positive and Negative Shatter Cones in a Limestone Block Stored at the Meteorkrater-Museum Steinheim, Germany

NASA Astrophysics Data System (ADS)

Buchner, E.; Hoelzel, M.; Schmieder, M.; Rasser, M.; Fietzke, J.; Frische, M.; Kutterolf, S.

2017-07-01

A metallic fragment on a shatter cone surface of a shattered limestone block is composed of Fe, Ni, and Co. Kamacite, taenite, troilite, and schreibersite were identified. These findings suggest this fragment is a piece of the Steinheim projectile.

Rice Domestication Revealed by Reduced Shattering of Archaeological rice from the Lower Yangtze valley

NASA Astrophysics Data System (ADS)

Zheng, Yunfei; Crawford, Gary W.; Jiang, Leping; Chen, Xugao

2016-06-01

Plant remains dating to between 9000 and 8400 BP from a probable ditch structure at the Huxi site include the oldest rice (Oryza sativa) spikelet bases and associated plant remains recovered in China. The remains document an early stage of rice domestication and the ecological setting in which early cultivation was taking place. The rice spikelet bases from Huxi include wild (shattering), intermediate, and domesticated (non-shattering) forms. The relative frequency of intermediate and non-shattering spikelet bases indicates that selection for, at the very least, non-shattering rice was underway at Huxi. The rice also has characteristics of japonica rice (Oryza sativa subsp. japonica), helping to clarify the emergence of a significant lineage of the crop. Seeds, phytoliths and their context provide evidence of increasing anthropogenesis and cultivation during the occupation. Rice spikelet bases from Kuahuqiao (8000-7700 BP), Tianluoshan (7000-6500 BP), Majiabang (6300-6000 BP), and Liangzhu (5300-4300 BP) sites indicate that rice underwent continuing selection for reduced shattering and japonica rice characteristics, confirming a prolonged domestication process for rice.

Lava tube shatter rings and their correlation with lava flux increases at Kīlauea Volcano, Hawai‘i

USGS Publications Warehouse

Orr, T.R.

2011-01-01

Shatter rings are circular to elliptical volcanic features, typically tens of meters in diameter, which form over active lava tubes. They are typified by an upraised rim of blocky rubble and a central depression. Prior to this study, shatter rings had not been observed forming, and, thus, were interpreted in many ways. This paper describes the process of formation for shatter rings observed at Kīlauea Volcano during November 2005–July 2006. During this period, tilt data, time-lapse images, and field observations showed that episodic tilt changes at the nearby Pu‘u ‘Ō‘ō cone, the shallow magmatic source reservoir, were directly related to fluctuations in the level of lava in the active lava tube, with periods of deflation at Pu‘u ‘Ō‘ō correlating with increases in the level of the lava stream surface. Increases in lava level are interpreted as increases in lava flux, and were coincident with lava breakouts from shatter rings constructed over the lava tube. The repetitive behavior of the lava flux changes, inferred from the nearly continuous tilt oscillations, suggests that shatter rings form from the repeated rise and fall of a portion of a lava tube roof. The locations of shatter rings along the active lava tube suggest that they form where there is an abrupt decrease in flow velocity through the tube, e.g., large increase in tube width, abrupt decrease in tube slope, and (or) sudden change in tube direction. To conserve volume, this necessitates an abrupt increase in lava stream depth and causes over-pressurization of the tube. More than a hundred shatter rings have been identified on volcanoes on Hawai‘i and Maui, and dozens have been reported from basaltic lava fields in Iceland, Australia, Italy, Samoa, and the mainland United States. A quick study of other basaltic lava fields worldwide, using freely available satellite imagery, suggests that they might be even more common than previously thought. If so, this confirms that episodic fluctuation in lava effusion rate is a relatively common process at basaltic volcanoes, and that the presence of shatter rings in prehistoric lava flow fields can be used as evidence that such fluctuations have occurred.

A comprehensive transcriptome analysis of silique development and dehiscence in Arabidopsis and Brassica integrating genotypic, interspecies and developmental comparisons.

PubMed

Jaradat, Masrur R; Ruegger, Max; Bowling, Andrew; Butler, Holly; Cutler, Adrian J

2014-01-01

Asynchronous flowering of Brassica napus (canola) leads to seeds and siliques at varying stages of maturity as harvest approaches. This range of maturation can result in premature silique dehiscence (pod shattering), resulting in yield losses, which may be worsened by environmental stresses. Therefore, a goal for canola crop improvement is to reduce shattering in order to maximize yield. We performed a comprehensive transcriptome analysis on the dehiscence zone (DZ) and valve of Arabidopsis and Brassica siliques in shatter resistant and sensitive genotypes at several developmental stages. Among known Arabidopsis dehiscence genes, we confirmed that homologs of SHP1/2, FUL, ADPG1, NST1/3 and IND were associated with shattering in B. juncea and B. napus. We noted a correlation between reduced pectin degradation genes and shatter-resistance. Tension between lignified and non-lignified cells in the silique DZ plays a major role in dehiscence. Light microscopy revealed a smaller non-lignified separation layer in relatively shatter-resistant B. juncea relative to B. napus and this corresponded to increased expression of peroxidases involved in monolignol polymerization. Sustained repression of auxin biosynthesis, transport and signaling in B. juncea relative to B. napus may cause differences in dehiscence zone structure and cell wall constituents. Tension on the dehiscence zone is a consequence of shrinkage and loss of flexibility in the valves, which is caused by senescence and desiccation. Reduced shattering was generally associated with upregulation of ABA signaling and down-regulation of ethylene and jasmonate signaling, corresponding to more pronounced stress responses and reduced senescence and photosynthesis. Overall, we identified 124 cell wall related genes and 103 transcription factors potentially involved in silique dehiscence.

A comprehensive transcriptome analysis of silique development and dehiscence in Arabidopsis and Brassica integrating genotypic, interspecies and developmental comparisons

PubMed Central

Jaradat, Masrur R; Ruegger, Max; Bowling, Andrew; Butler, Holly; Cutler, Adrian J

2014-01-01

Asynchronous flowering of Brassica napus (canola) leads to seeds and siliques at varying stages of maturity as harvest approaches. This range of maturation can result in premature silique dehiscence (pod shattering), resulting in yield losses, which may be worsened by environmental stresses. Therefore, a goal for canola crop improvement is to reduce shattering in order to maximize yield. We performed a comprehensive transcriptome analysis on the dehiscence zone (DZ) and valve of Arabidopsis and Brassica siliques in shatter resistant and sensitive genotypes at several developmental stages. Among known Arabidopsis dehiscence genes, we confirmed that homologs of SHP1/2, FUL, ADPG1, NST1/3 and IND were associated with shattering in B. juncea and B. napus. We noted a correlation between reduced pectin degradation genes and shatter-resistance. Tension between lignified and non-lignified cells in the silique DZ plays a major role in dehiscence. Light microscopy revealed a smaller non-lignified separation layer in relatively shatter-resistant B. juncea relative to B. napus and this corresponded to increased expression of peroxidases involved in monolignol polymerization. Sustained repression of auxin biosynthesis, transport and signaling in B. juncea relative to B. napus may cause differences in dehiscence zone structure and cell wall constituents. Tension on the dehiscence zone is a consequence of shrinkage and loss of flexibility in the valves, which is caused by senescence and desiccation. Reduced shattering was generally associated with upregulation of ABA signaling and down-regulation of ethylene and jasmonate signaling, corresponding to more pronounced stress responses and reduced senescence and photosynthesis. Overall, we identified 124 cell wall related genes and 103 transcription factors potentially involved in silique dehiscence. PMID:25523176

The Fate of Saudi Arabia: Regime Evolution in the Saudi Monarchy

DTIC Science & Technology

2008-12-01

on women drivers by pointing out advantages to economy if women drove,141 and “Shattering Glass Ceilings at Lingerie Shops,” which criticized a law to...http://www.arabnews.com/?page=1§ion=0&article=108366&d=29&m=3&y=2008 (accessed November 30, 2008) 142 Najah Alosaimi, “Shattering Glass Ceilings at...accessed December 4, 2008). Alosaimi, Najah. “Shattering Glass Ceilings at Lingerie Shops.” Arab News, October 15, 2008. http://www.arabnews.com

Shatter cones: (Mis)understood?

PubMed

Osinski, Gordon R; Ferrière, Ludovic

2016-08-01

Meteorite impact craters are one of the most common geological features in the solar system. An impact event is a near-instantaneous process that releases a huge amount of energy over a very small region on a planetary surface. This results in characteristic changes in the target rocks, from vaporization and melting to solid-state effects, such as fracturing and shock metamorphism. Shatter cones are distinctive striated conical fractures that are considered unequivocal evidence of impact events. They are one of the most used and trusted shock-metamorphic effects for the recognition of meteorite impact structures. Despite this, there is still considerable debate regarding their formation. We show that shatter cones are present in several stratigraphic settings within and around impact structures. Together with the occurrence of complete and "double" cones, our observations are most consistent with shatter cone formation due to tensional stresses generated by scattering of the shock wave due to heterogeneities in the rock. On the basis of field mapping, we derive the relationship D sc = 0.4 D a, where D sc is the maximum spatial extent of in situ shatter cones, and D a is the apparent crater diameter. This provides an important, new, more accurate method to estimate the apparent diameter of eroded complex craters on Earth. We have reestimated the diameter of eight well-known impact craters as part of this study. Finally, we suggest that shatter cones may reduce the strength of the target, thus aiding crater collapse, and that their distribution in central uplifts also records the obliquity of impact.

Shatter cones: (Mis)understood?

PubMed Central

Osinski, Gordon R.; Ferrière, Ludovic

2016-01-01

Meteorite impact craters are one of the most common geological features in the solar system. An impact event is a near-instantaneous process that releases a huge amount of energy over a very small region on a planetary surface. This results in characteristic changes in the target rocks, from vaporization and melting to solid-state effects, such as fracturing and shock metamorphism. Shatter cones are distinctive striated conical fractures that are considered unequivocal evidence of impact events. They are one of the most used and trusted shock-metamorphic effects for the recognition of meteorite impact structures. Despite this, there is still considerable debate regarding their formation. We show that shatter cones are present in several stratigraphic settings within and around impact structures. Together with the occurrence of complete and “double” cones, our observations are most consistent with shatter cone formation due to tensional stresses generated by scattering of the shock wave due to heterogeneities in the rock. On the basis of field mapping, we derive the relationship Dsc = 0.4 Da, where Dsc is the maximum spatial extent of in situ shatter cones, and Da is the apparent crater diameter. This provides an important, new, more accurate method to estimate the apparent diameter of eroded complex craters on Earth. We have reestimated the diameter of eight well-known impact craters as part of this study. Finally, we suggest that shatter cones may reduce the strength of the target, thus aiding crater collapse, and that their distribution in central uplifts also records the obliquity of impact. PMID:27532050

OsGRF4 controls grain shape, panicle length and seed shattering in rice

PubMed Central

Sun, Pingyong; Zhang, Wuhan; Wang, Yihua; He, Qiang; Shu, Fu; Liu, Hai; Wang, Jie; Wang, Jianmin; Yuan, Longping

2016-01-01

Abstract Traits such as grain shape, panicle length and seed shattering, play important roles in grain yield and harvest. In this study, the cloning and functional analysis of PANICLE TRAITS 2 (PT2), a novel gene from the Indica rice Chuandali (CDL), is reported. PT2 is synonymous with Growth‐Regulating Factor 4 (OsGRF4), which encodes a growth‐regulating factor that positively regulates grain shape and panicle length and negatively regulates seed shattering. Higher expression of OsGRF4 is correlated with larger grain, longer panicle and lower seed shattering. A unique OsGRF4 mutation, which occurs at the OsmiRNA396 target site of OsGRF4, seems to be associated with high levels of OsGRF4 expression, and results in phenotypic difference. Further research showed that OsGRF4 regulated two cytokinin dehydrogenase precursor genes (CKX5 and CKX1) resulting in increased cytokinin levels, which might affect the panicle traits. High storage capacity and moderate seed shattering of OsGRF4 may be useful in high‐yield breeding and mechanized harvesting of rice. Our findings provide additional insight into the molecular basis of panicle growth. PMID:26936408

Stress induced by premature chromatin condensation triggers chromosome shattering and chromothripsis at DNA sites still replicating in micronuclei or multinucleate cells when primary nuclei enter mitosis.

PubMed

Terzoudi, Georgia I; Karakosta, Maria; Pantelias, Antonio; Hatzi, Vasiliki I; Karachristou, Ioanna; Pantelias, Gabriel

2015-11-01

Combination of next-generation DNA sequencing, single nucleotide polymorphism array analyses and bioinformatics has revealed the striking phenomenon of chromothripsis, described as complex genomic rearrangements acquired in a single catastrophic event affecting one or a few chromosomes. Via an unproven mechanism, it is postulated that mechanical stress causes chromosome shattering into small lengths of DNA, which are then randomly reassembled by DNA repair machinery. Chromothripsis is currently examined as an alternative mechanism of oncogenesis, in contrast to the present paradigm that considers a stepwise development of cancer. While evidence for the mechanism(s) underlying chromosome shattering during cancer development remains elusive, a number of hypotheses have been proposed to explain chromothripsis, including ionizing radiation, DNA replication stress, breakage-fusion-bridge cycles, micronuclei formation and premature chromosome compaction. In the present work, we provide experimental evidence on the mechanistic basis of chromothripsis and on how chromosomes can get locally shattered in a single catastrophic event. Considering the dynamic nature of chromatin nucleoprotein complex, capable of rapid unfolding, disassembling, assembling and refolding, we first show that chromatin condensation at repairing or replicating DNA sites induces the mechanical stress needed for chromosome shattering to ensue. Premature chromosome condensation is then used to visualize the dynamic nature of interphase chromatin and demonstrate that such mechanical stress and chromosome shattering can also occur in chromosomes within micronuclei or asynchronous multinucleate cells when primary nuclei enter mitosis. Following an aberrant mitosis, chromosomes could find themselves in the wrong place at the wrong time so that they may undergo massive DNA breakage and rearrangement in a single catastrophic event. Specifically, our results support the hypothesis that premature chromosome condensation induces mechanical stress and triggers shattering and chromothripsis in chromosomes or chromosome arms still undergoing DNA replication or repair in micronuclei or asynchronous multinucleate cells, when primary nuclei enter mitosis. Copyright © 2015 Elsevier B.V. All rights reserved.

OsGRF4 controls grain shape, panicle length and seed shattering in rice.

PubMed

Sun, Pingyong; Zhang, Wuhan; Wang, Yihua; He, Qiang; Shu, Fu; Liu, Hai; Wang, Jie; Wang, Jianmin; Yuan, Longping; Deng, Huafeng

2016-10-01

Traits such as grain shape, panicle length and seed shattering, play important roles in grain yield and harvest. In this study, the cloning and functional analysis of PANICLE TRAITS 2 (PT2), a novel gene from the Indica rice Chuandali (CDL), is reported. PT2 is synonymous with Growth-Regulating Factor 4 (OsGRF4), which encodes a growth-regulating factor that positively regulates grain shape and panicle length and negatively regulates seed shattering. Higher expression of OsGRF4 is correlated with larger grain, longer panicle and lower seed shattering. A unique OsGRF4 mutation, which occurs at the OsmiRNA396 target site of OsGRF4, seems to be associated with high levels of OsGRF4 expression, and results in phenotypic difference. Further research showed that OsGRF4 regulated two cytokinin dehydrogenase precursor genes (CKX5 and CKX1) resulting in increased cytokinin levels, which might affect the panicle traits. High storage capacity and moderate seed shattering of OsGRF4 may be useful in high-yield breeding and mechanized harvesting of rice. Our findings provide additional insight into the molecular basis of panicle growth. © 2016 The Authors. Journal of Integrative Plant Biology Published by John Wiley & Sons Australia, Ltd on behalf of Institute of Botany, Chinese Academy of Sciences.

Breccia dikes from the Beaverhead Impact structure, southwest Montana

NASA Technical Reports Server (NTRS)

Fiske, P. S.; Hougen, S. B.; Hargraves, R. B.

1992-01-01

While shatter cones are generally accepted as indicators of meteorite impact, older petrologic features are not widely recognized in the geologic community. Breccia dikes are one such feature. They are found in many large impact structures occurring over an area at least as extensively as shatter cones. Breccia dikes will survive moderate degrees of metamorphism and tectonism, unlike many other microscopic features (shocked quartz grains, high-pressure polymorphs, etc.) and even large-scale features such as annular or bowl-shaped topographic features. Thus, they are important diagnostic criteria, especially for large, poorly preserved impact structures. The Beaverhead Impact structure is a recently discovered, deeply eroded impact structure in southwestern Montana. The remains of the structure are delineated by the occurrence of shatter cones, found in an area greater than 200 sq km, occurring within the Cabin thrust plate, part of the Cretaceous Sevier fold and thrust system. The distribution of shatter cones is further truncated by Tertiary normal faults. The present remains represent an allochthonous fragment of a larger structure.

Molecular evolution of the sh4 shattering locus in U.S. weedy rice

USDA-ARS?s Scientific Manuscript database

Cultivated rice fields worldwide are plagued with weedy rice, a congeneric weed of cultivated rice (Oryza sativa L.). The persistence of weedy rice has been attributed, in part, to its ability to shatter (disperse) seed prior to crop harvesting. In the United States, separately evolved weedy rice g...

Bonding Lexan and sapphire to form high-pressure, flame-resistant window

NASA Technical Reports Server (NTRS)

Richardson, William R.; Walker, Ernie D.

1987-01-01

Flammable materials have been studied in normal gravity and microgravity for many years. Photography plays a major role in the study of the combustion process giving a permanent visual record that can be analyzed. When these studies are extended to manned spacecraft, safety becomes a primary concern. The need for a high-pressure, flame-resistant, shatter-resistant window permitting photographic recording of combustion experiments in manned spacecraft prompted the development of a method for bonding Lexan and sapphire. Materials that resist shattering (e.g., Lexan) are not compatible with combustion experiments; the material loses strength at combustion temperatures. Sapphire is compatible with combustion temperatures in oxygen-enriched atmospheres but is subject to shattering. Combining the two materials results in a shatter-resistant, flame-resistant window. Combustion in microgravity produces a low-visibility flame; however, flame propagation and flame characteristics are readily visible as long as there is no deterioration of the image. Since an air gap between the Lexan and the sapphire would reduce transmission, a method was developed for bonding these unlike materials to minimize light loss.

BnLATE, a Cys2/His2-Type Zinc-Finger Protein, Enhances Silique Shattering Resistance by Negatively Regulating Lignin Accumulation in the Silique Walls of Brassica napus

PubMed Central

Tao, Zhangsheng; Huang, Yi; Zhang, Lida; Wang, Xinfa; Liu, Guihua; Wang, Hanzhong

2017-01-01

Silique shattering resistance is one of the most important agricultural traits in oil crop breeding. Seed shedding from siliques prior to and during harvest causes devastating losses in oilseed yield. Lignin biosynthesis in the silique walls is thought to affect silique-shattering resistance in oil crops. Here, we identified and characterized B. napus LATE FLOWERING (BnLATE), which encodes a Cys2/His2-type zinc-finger protein. Heterologous expression of BnLATE under the double enhanced CaMV 35S promoter (D35S) in wild-type Arabidopsis plants resulted in a marked decrease in lignification in the replum, valve layer (carpel) and dehiscence zone. pBnLATE::GUS activity was strong in the yellowing silique walls of transgenic lines. Furthermore, the expression pattern of BnLATE and the lignin content gradient in the silique walls at 48 days after pollination (DAP) of 73290, a B. napus silique shattering-resistant line, are similar to those in transgenic Arabidopsis lines expressing BnLATE. Transcriptome sequencing of the silique walls revealed that genes encoding peroxidases, which polymerize monolignols and lignin in the phenylpropanoid pathway, were down-regulated at least two-fold change in the D35S::BnLATE transgenic lines. pBnLATE::BnLATE transgenic lines were further used to identify the function of BnLATE, and the results showed that lignification in the carpel and dehiscence zone of yellowing silique also remarkably decreased compared with the wild-type control, the silique shattering-resistance and expression pattern of peroxidase genes are very similar to results with D35S::BnLATE. These results suggest that BnLATE is a negative regulator of lignin biosynthesis in the yellowing silique walls, and promotes silique-shattering resistance in B. napus through restraining the polymerization of monolignols and lignin. PMID:28081140

Characteristics of Whipple Shield Performance in the Shatter Regime

NASA Technical Reports Server (NTRS)

Ryan, S.; Bjorkman, M.; Christiansen, E. L.

2010-01-01

Ballistic limit equations define the failure of metallic Whipple shields in three parts: low velocity, shatter, and hypervelocity. Failure limits in the shatter regime are based on a linear interpolation between the onset of projectile fragmentation, and impulsive rupture of the shield rear wall. A series of hypervelocity impact tests have been performed on aluminum alloy Whipple shields to investigate failure mechanisms and performance limits in the shatter regime. Test results demonstrated a more rapid increase in performance than predicted by the latest iteration of the JSC Whipple shield BLE following the onset of projectile fragmentation. This increase in performance was found to level out between 4.0-5.0 km/s, with a subsequent decrease in performance for velocities up to 6.0 km/s. For a detached spall failure criterion, the failure limit was found to continually decrease up to a velocity of 7.0 km/s, substantially varying from the BLE, while for perforation-based failure an increase in performance was observed. An existing phenomenological ballistic limit curve was found to provide a more accurate reproduction of shield behavior that the BLE, however a number of underlying assumptions such as the occurrence of complete projectile fragmentation and the effect on performance of incipient projectile melt were found to be inaccurate. A cratering relationship based on the largest residual fragment size has been derived for application at velocities between 3.0-4.0 km/s, and was shown to accurately reproduce the trends of the experimental data. Further investigation is required to allow a full analytical description of shatter regime performance for metallic Whipple shields.

Interrelating the breakage and composition of mined and drill core coal

NASA Astrophysics Data System (ADS)

Wilson, Terril Edward

Particle size distribution of coal is important if the coal is to be beneficiated, or if a coal sales contract includes particle size specifications. An exploration bore core sample of coal ought to be reduced from its original cylindrical form to a particle size distribution and particle composition that reflects, insofar as possible, a process stream of raw coal it represents. Often, coal cores are reduced with a laboratory crushing machine, the product of which does not match the raw coal size distribution. This study proceeds from work in coal bore core reduction by Australian investigators. In this study, as differentiated from the Australian work, drop-shatter impact breakage followed by dry batch tumbling in steel cylinder rotated about its transverse axis are employed to characterize the core material in terms of first-order and zeroth-order breakage rate constants, which are indices of the propensity of the coal to degrade during excavation and handling. Initial drop-shatter and dry tumbling calibrations were done with synthetic cores composed of controlled low-strength concrete incorporating fly ash (as a partial substitute for Portland cement) in order to reduce material variables and conserve difficult-to-obtain coal cores. Cores of three different coalbeds--Illinois No. 6, Upper Freeport, and Pocahontas No. 5 were subjected to drop-shatter and dry batch tumbling tests to determine breakage response. First-order breakage, characterized by a first-order breakage index for each coal, occurred in the drop-shatter tests. First- and zeroth-order breakage occurred in dry batch tumbling; disappearance of coarse particles and creation of fine particles occurred in a systematic way that could be represented mathematically. Certain of the coal cores available for testing were dry and friable. Comparison of coal preparation plant feed with a crushed bore core and a bore core prepared by drop-shatter and tumbling (all from the same Illinois No.6 coal mining property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core. An attempt to determine breakage parameters (to allow use of selection and breakage functions and population balance models in the description of bore core size reduction) was initiated. Rank determination of the three coal types was done, indicating that higher rank associates with higher breakage propensity. The two step procedure of drop-shatter and dry batch tumbling simulates the first-order (volume breakage) and zeroth-order (abrasion of particle surfaces) that occur in excavation and handling operations, and is appropriate for drill core reduction prior to laboratory analysis.

Static versus dynamic fracturing in shallow carbonate fault zones

NASA Astrophysics Data System (ADS)

Fondriest, M.; Doan, M. L.; Aben, F. M.; Fusseis, F.; Mitchell, T. M.; Di Toro, G.

2015-12-01

Moderate to large earthquakes often nucleate within and propagate through carbonates in the shallow crust, therefore several field and experimental studies were recently aimed to constrain earthquake-related deformation processes within carbonate fault rocks. In particular, the occurrence of thick belts (10-100s m) of low-strain fault-related breccias (average size of rock fragments >1 cm), which is relatively common within carbonate damage zones, was generally interpreted as resulting from the quasi-static growth of fault zones rather than from the cumulative effect of multiple earthquake ruptures. Here we report the occurrence of up to hundreds of meters thick belts of intensely fragmented dolostones along the major transpressive Foiana Fault Zone (Italian Southern Alps) which was exhumed from < 2 km depth. Such dolostones are reduced into fragments ranging from few centimeters down to few millimeters in size with ultrafine-grained layers in proximity to the principal slip zones. Preservation of the original bedding indicates a lack of significant shear strain in the fragmented dolostones which seem to have been shattered in situ. To investigate the origin of the in-situ shattered rocks, the host dolostones were deformed in uniaxial compression both under quasi-static loading (strain rate ~10-3 s-1) and dynamic loading (strain rate >50 s-1). Dolostones deformed up to failure under low-strain rate were affected by single to multiple discrete (i.e. not interconnected) extensional fractures sub-parallel to the loading direction. Dolostones deformed under high-strain rate were shattered above a strain rate threshold of ~200 s-1(strain >1.2%) while they were split in few fragments or were macroscopically intact for lower strain rates. Experimentally shattered dolostones were reduced into a non-cohesive material with most rock fragments a few millimeters in size and elongated parallel to the loading direction. Fracture networks were investigated by X-ray microtomography showing that low- and high-strain rate damage patterns are different with the latter being similar to that of natural in-situ shattered dolostones. In-situ shattered dolostones are thus interpreted as the product of off-fault dynamic stress wave loading and can potentially be used to constrain coseismic energy release in fault zones.

RNAi-mediated down-regulation of SHATTERPROOF gene in transgenic oilseed rape.

PubMed

Kord, Hadis; Shakib, Ali Mohammad; Daneshvar, Mohammad Hossein; Azadi, Pejman; Bayat, Vahid; Mashayekhi, Mohsen; Zarea, Mahboobeh; Seifi, Alireza; Ahmad-Raji, Mana

2015-06-01

Oilseed rape is one of the important oil plants. Pod shattering is one of the problems in oilseed rape production especially in regions with dry conditions. One of the important genes in Brassica pod opening is SHATTERPROOF1 (SHP1). Down-regulation of BnSHP1 expression by RNAi can increase resistance to pod shattering. A 470 bp of the BnSHP1 cDNA sequence constructed in an RNAi-silencing vector was transferred to oilseed rape cv. SLM046. Molecular analysis of T2 transgenic plants by RT-PCR and Real-time PCR showed that expression of the BnSHP alleles was highly decreased in comparison with control plants. Morphologically, transgenic plants were normal and produced seeds at greenhouse conditions. At ripening, stage pods failed to shatter, and a finger pressure was needed for pod opening.

ShatterProof: operational detection and quantification of chromothripsis.

PubMed

Govind, Shaylan K; Zia, Amin; Hennings-Yeomans, Pablo H; Watson, John D; Fraser, Michael; Anghel, Catalina; Wyatt, Alexander W; van der Kwast, Theodorus; Collins, Colin C; McPherson, John D; Bristow, Robert G; Boutros, Paul C

2014-03-19

Chromothripsis, a newly discovered type of complex genomic rearrangement, has been implicated in the evolution of several types of cancers. To date, it has been described in bone cancer, SHH-medulloblastoma and acute myeloid leukemia, amongst others, however there are still no formal or automated methods for detecting or annotating it in high throughput sequencing data. As such, findings of chromothripsis are difficult to compare and many cases likely escape detection altogether. We introduce ShatterProof, a software tool for detecting and quantifying chromothriptic events. ShatterProof takes structural variation calls (translocations, copy-number variations, short insertions and loss of heterozygosity) produced by any algorithm and using an operational definition of chromothripsis performs robust statistical tests to accurately predict the presence and location of chromothriptic events. Validation of our tool was conducted using clinical data sets including matched normal, prostate cancer samples in addition to the colorectal cancer and SCLC data sets used in the original description of chromothripsis. ShatterProof is computationally efficient, having low memory requirements and near linear computation time. This allows it to become a standard component of sequencing analysis pipelines, enabling researchers to routinely and accurately assess samples for chromothripsis. Source code and documentation can be found at http://search.cpan.org/~sgovind/Shatterproof.

Shatter resistance of spectacle lenses.

PubMed

Vinger, P F; Parver, L; Alfaro, D V; Woods, T; Abrams, B S

1997-01-08

To evaluate the relative strength and shatter resistance of spectacle lenses currently used in sunglasses and dress, sports, and industrial eyewear. Seven lenses that met the US American National Standards Institute (ANSI) Z80 standards for dress glasses (made of high-index plastic, allyl resin plastic, heat tempered glass, chemically tempered glass, and polycarbonate, and with center thickness ranging from 1 mm to 2.2 mm) and 4 lenses that met ANSI Z87 standards for industrial safety eyewear (allyl resin plastic, heat-tempered glass, chemically tempered glass, and polycarbonate, all with 3.0-mm center thickness) were tested for impact resistance to 5 projectiles (air gun pellets, golf balls, tennis balls, lacrosse balls, and baseballs). Impact energy required to shatter spectacle lenses. Based on 348 lens impacts, dress and industrial lenses made from glass, allyl resin plastic, and high-index plastic shattered at impact energies less than those expected to be encountered from the test projectiles during their routine use. Polycarbonate lenses demonstrated resistance to impact for all tested projectiles exceeding the impact potential expected during routine use. Under the test conditions of this study, polycarbonate lenses demonstrated greater impact resistance than other commonly used spectacle lenses that conform to prevailing eyewear standards. These findings suggest that current ANSI Z80 and ANSI Z87 standards should be reevaluated.

Automatic identification and location technology of glass insulator self-shattering

NASA Astrophysics Data System (ADS)

Huang, Xinbo; Zhang, Huiying; Zhang, Ye

2017-11-01

The insulator of transmission lines is one of the most important infrastructures, which is vital to ensure the safe operation of transmission lines under complex and harsh operating conditions. The glass insulator often self-shatters but the available identification methods are inefficient and unreliable. Then, an automatic identification and localization technology of self-shattered glass insulators is proposed, which consists of the cameras installed on the tower video monitoring devices or the unmanned aerial vehicles, the 4G/OPGW network, and the monitoring center, where the identification and localization algorithm is embedded into the expert software. First, the images of insulators are captured by cameras, which are processed to identify the region of insulator string by the presented identification algorithm of insulator string. Second, according to the characteristics of the insulator string image, a mathematical model of the insulator string is established to estimate the direction and the length of the sliding blocks. Third, local binary pattern histograms of the template and the sliding block are extracted, by which the self-shattered insulator can be recognized and located. Finally, a series of experiments is fulfilled to verify the effectiveness of the algorithm. For single insulator images, Ac, Pr, and Rc of the algorithm are 94.5%, 92.38%, and 96.78%, respectively. For double insulator images, Ac, Pr, and Rc are 90.00%, 86.36%, and 93.23%, respectively.

Discovery of Pod Shatter-Resistant Associated SNPs by Deep Sequencing of a Representative Library Followed by Bulk Segregant Analysis in Rapeseed

PubMed Central

Huang, Shunmou; Yang, Hongli; Zhan, Gaomiao; Wang, Xinfa; Liu, Guihua; Wang, Hanzhong

2012-01-01

Background Single nucleotide polymorphisms (SNPs) are an important class of genetic marker for target gene mapping. As of yet, there is no rapid and effective method to identify SNPs linked with agronomic traits in rapeseed and other crop species. Methodology/Principal Findings We demonstrate a novel method for identifying SNP markers in rapeseed by deep sequencing a representative library and performing bulk segregant analysis. With this method, SNPs associated with rapeseed pod shatter-resistance were discovered. Firstly, a reduced representation of the rapeseed genome was used. Genomic fragments ranging from 450–550 bp were prepared from the susceptible bulk (ten F2 plants with the silique shattering resistance index, SSRI <0.10) and the resistance bulk (ten F2 plants with SSRI >0.90), and also Solexa sequencing-produced 90 bp reads. Approximately 50 million of these sequence reads were assembled into contigs to a depth of 20-fold coverage. Secondly, 60,396 ‘simple SNPs’ were identified, and the statistical significance was evaluated using Fisher's exact test. There were 70 associated SNPs whose –log10 p value over 16 were selected to be further analyzed. The distribution of these SNPs appeared a tight cluster, which consisted of 14 associated SNPs within a 396 kb region on chromosome A09. Our evidence indicates that this region contains a major quantitative trait locus (QTL). Finally, two associated SNPs from this region were mapped on a major QTL region. Conclusions/Significance 70 associated SNPs were discovered and a major QTL for rapeseed pod shatter-resistance was found on chromosome A09 using our novel method. The associated SNP markers were used for mapping of the QTL, and may be useful for improving pod shatter-resistance in rapeseed through marker-assisted selection and map-based cloning. This approach will accelerate the discovery of major QTLs and the cloning of functional genes for important agronomic traits in rapeseed and other crop species. PMID:22529909

Identifying Water on Mt. Baker and Mt. St. Helens, WA with Geophysics: Implications for Volcanic Landslide Hazards

NASA Astrophysics Data System (ADS)

Finn, C.; Bedrosian, P.; Wisniewski, M.; Deszcz-Pan, M.

2015-12-01

Groundwater position, abundance, and flow rates within a volcano affect the transmission of fluid pressure, transport of mass and heat and formation of mechanically weak hydrothermal alteration influencing the stability of volcanoes. In addition, eruptions can shatter volcanic rocks, weakening the edifice. Helicopter magnetic and electromagnetic (HEM) data collected over Mt. Baker and Mt. St. Helens volcanoes reveal the distribution of water, shattered volcanic rocks and hydrothermal alteration essential to evaluating volcanic landslide hazards. These data, combined with geological mapping and rock property measurements, indicate the presence of localized <100 m thick zones of water-saturated hydrothermally altered rock beneath Sherman Crater and the Dorr Fumarole Fields at Mt. Baker. Nuclear magnetic resonance data indicate that the hydrothermal clays contain ~50% bound water with no evidence for free water ponded beneath the ice. The HEM data suggest water-saturated fresh volcanic rocks from the surface to the detection limit (~100 m) over the entire summit of Mt. Baker (below the ice). A 50-100 m thick high resistivity layer (>1500 ohm-m) corresponding to domes, debris avalanche, volcanic rocks and glaciers mantles the crater at Mt. St. Helens. Shallow low resistivity layers corresponding to fresh, cold water and hot brines are observed below the high resistivity surface in EM data. Shallow ground water mainly concentrates in shattered dome material in the crater of Mt. St. Helens. Aeromagnetic data indicate the location of basalts sandwiched between debris avalanche deposits and shattered dome material. The combination of the EM and magnetic data help map the location of the shattered dome material that is considered to be the failure surface for the 1980 debris avalanche. The EM data image the regional groundwater table near the base of the volcano. The geophysical identification of groundwater and weak layers constrain landslide hazards assessments.

Rock sample brought to earth from the Apollo 12 lunar landing mission

NASA Technical Reports Server (NTRS)

1969-01-01

A scientist's gloved hand holds one of the numerous rock samples brought back to Earth from the Apollo 12 lunar landing mission. This sample is a highly shattered basaltic rock with a thin black-glass coating on five of its six sides. Glass fills fractures and cements the rock together. The rock appears to have been shattered and thrown out by a meteorite impact explosion and coated with molten rock material before the rock fell to the surface.

FAST TRACK COMMUNICATION: The nonlinear fragmentation equation

NASA Astrophysics Data System (ADS)

Ernst, Matthieu H.; Pagonabarraga, Ignacio

2007-04-01

We study the kinetics of nonlinear irreversible fragmentation. Here, fragmentation is induced by interactions/collisions between pairs of particles and modelled by general classes of interaction kernels, for several types of breakage models. We construct initial value and scaling solutions of the fragmentation equations, and apply the 'non-vanishing mass flux' criterion for the occurrence of shattering transitions. These properties enable us to determine the phase diagram for the occurrence of shattering states and of scaling states in the phase space of model parameters.

Experiments and scaling laws for catastrophic collisions. [of asteroids

NASA Technical Reports Server (NTRS)

Fujiwara, A.; Cerroni, P.; Davis, D.; Ryan, E.; Di Martino, M.

1989-01-01

The existing data on shattering impacts are reviewed using natural silicate, ice, and cement-mortar targets. A comprehensive data base containing the most important parameters describing these experiments was prepared. The collisional energy needed to shatter consolidated homogeneous targets and the ensuing fragment size distributions have been well studied experimentally. However, major gaps exist in the data on fragment velocity and rotational distributions, as well as collisional energy partitioning for these targets. Current scaling laws lead to predicted outcomes of asteroid collisions that are inconsistent with interpretations of astronomical data.

Molecular basis of a shattering resistance boosting global dissemination of soybean

PubMed Central

Funatsuki, Hideyuki; Suzuki, Masaya; Hirose, Aya; Inaba, Hiroki; Yamada, Tetsuya; Hajika, Makita; Komatsu, Kunihiko; Katayama, Takeshi; Sayama, Takashi; Ishimoto, Masao; Fujino, Kaien

2014-01-01

Pod dehiscence (shattering) is essential for the propagation of wild plant species bearing seeds in pods but is a major cause of yield loss in legume and crucifer crops. Although natural genetic variation in pod dehiscence has been, and will be, useful for plant breeding, little is known about the molecular genetic basis of shattering resistance in crops. Therefore, we performed map-based cloning to unveil a major quantitative trait locus (QTL) controlling pod dehiscence in soybean. Fine mapping and complementation testing revealed that the QTL encodes a dirigent-like protein, designated as Pdh1. The gene for the shattering-resistant genotype, pdh1, was defective, having a premature stop codon. The functional gene, Pdh1, was highly expressed in the lignin-rich inner sclerenchyma of pod walls, especially at the stage of initiation in lignin deposition. Comparisons of near-isogenic lines indicated that Pdh1 promotes pod dehiscence by increasing the torsion of dried pod walls, which serves as a driving force for pod dehiscence under low humidity. A survey of soybean germplasm revealed that pdh1 was frequently detected in landraces from semiarid regions and has been extensively used for breeding in North America, the world’s leading soybean producer. These findings point to a new mechanism for pod dehiscence involving the dirigent protein family and suggest that pdh1 has played a crucial role in the global expansion of soybean cultivation. Furthermore, the orthologs of pdh1, or genes with the same role, will possibly be useful for crop improvement. PMID:25468966

Dissipation of post-disruption runaway electron plateaus by shattered pellet injection in DIII-D

NASA Astrophysics Data System (ADS)

Shiraki, D.; Commaux, N.; Baylor, L. R.; Cooper, C. M.; Eidietis, N. W.; Hollmann, E. M.; Paz-Soldan, C.; Combs, S. K.; Meitner, S. J.

2018-05-01

We report on the first demonstration of dissipation of fully avalanched post-disruption runaway electron (RE) beams by shattered pellet injection in the DIII-D tokamak. Variation of the injected species shows that dissipation depends strongly on the species mixture, while comparisons with massive gas injection do not show a significant difference between dissipation by pellets or by gas, suggesting that the shattered pellet is rapidly ablated by the relativistic electrons before significant radial penetration into the runaway beam can occur. Pure or dominantly neon injection increases the RE current dissipation through pitch-angle scattering due to collisions with impurity ions. Deuterium injection is observed to have the opposite effect from neon, reducing the high-Z impurity content and thus decreasing the dissipation, and causing the background thermal plasma to completely recombine. When injecting mixtures of the two species, deuterium levels as low as  ∼10% of the total injected atoms are observed to adversely affect the resulting dissipation, suggesting that complete elimination of deuterium from the injection may be important for optimizing RE mitigation schemes.

Dissipation of post-disruption runaway electron plateaus by shattered pellet injection in DIII-D

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

Shiraki, D.; Commaux, N.; Baylor, L. R.

Here, we report on the first demonstration of dissipation of fully avalanched post-disruption runaway electron (RE) beams by shattered pellet injection in the DIII-D tokamak. Variation of the injected species shows that dissipation depends strongly on the species mixture, while comparisons with massive gas injection do not show a significant difference between dissipation by pellets or by gas, suggesting that the shattered pellet is rapidly ablated by the relativistic electrons before significant radial penetration into the runaway beam can occur. Pure or dominantly neon injection increases the RE current dissipation through pitch-angle scattering due to collisions with impurity ions. Deuteriummore » injection is observed to have the opposite effect from neon, causing the background thermal plasma to completely recombine, reducing the high-Z impurity content and thus decreasing the dissipation. When injecting mixtures of the two species, deuterium levels as low as ~10% of the total injected atoms are observed to adversely affect the resulting dissipation, suggesting that complete elimination of deuterium from the injection may be important for optimizing RE mitigation schemes.« less

Dissipation of post-disruption runaway electron plateaus by shattered pellet injection in DIII-D

DOE PAGES

Shiraki, D.; Commaux, N.; Baylor, L. R.; ...

2018-03-07

Here, we report on the first demonstration of dissipation of fully avalanched post-disruption runaway electron (RE) beams by shattered pellet injection in the DIII-D tokamak. Variation of the injected species shows that dissipation depends strongly on the species mixture, while comparisons with massive gas injection do not show a significant difference between dissipation by pellets or by gas, suggesting that the shattered pellet is rapidly ablated by the relativistic electrons before significant radial penetration into the runaway beam can occur. Pure or dominantly neon injection increases the RE current dissipation through pitch-angle scattering due to collisions with impurity ions. Deuteriummore » injection is observed to have the opposite effect from neon, causing the background thermal plasma to completely recombine, reducing the high-Z impurity content and thus decreasing the dissipation. When injecting mixtures of the two species, deuterium levels as low as ~10% of the total injected atoms are observed to adversely affect the resulting dissipation, suggesting that complete elimination of deuterium from the injection may be important for optimizing RE mitigation schemes.« less

Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Nino-Southern Oscillation records

USGS Publications Warehouse

Keefer, David K.; Moseley, Michael E.

2004-01-01

In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2-8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term "shattered landscape" to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Nin??o events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Nin??o-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion.

Lunar Samples - Apollo 12

NASA Image and Video Library

1969-11-28

S69-60354 (29 Nov. 1969) --- A scientist's gloved hand holds one of the numerous rock samples brought back to Earth from the Apollo 12 lunar landing mission. The rocks are under thorough examination in the Manned Spacecraft Center's (MSC) Lunar Receiving Laboratory (LRL). This sample is a highly shattered basaltic rock with a thin black-glass coating on five of its six sides. Glass fills fractures and cements the rock together. The rock appears to have been shattered and thrown out by a meteorite impact explosion and coated with molten rock material before the rock fell to the surface.

On the Importance of Small Ice Crystals in Tropical Anvil Cirrus

NASA Technical Reports Server (NTRS)

Jensen, E. J.; Lawson, P.; Baker, B.; Pilson, B.; Mo, Q.; Heymsfield, A. J.; Bansemer, A.; Bui, T. P.; McGill, M.; Hlavka, D.;

Thermal quench mitigation and current quench control by injection of mixed species shattered pellets in DIII-D

DOE PAGES

Shiraki, D.; Commaux, N.; Baylor, L. R.; ...

2016-06-27

Injection of large shattered pellets composed of variable quantities of the main ion species (deuterium) and high-Z impurities (neon) in the DIII-D tokamak demonstrate control of thermal quench (TQ) and current quench (CQ) properties in mitigated disruptions. As the pellet composition is varied, TQ radiation fractions increase continuously with the quantity of radiating impurity in the pellet, with a corresponding decrease in divertor heating. Post-TQ plasma resistivities increase as a result of the higher radiation fraction, allowing control of current decay timescales based on the pellet composition. Magnetic reconstructions during the CQ show that control of the current decay ratemore » allows continuous variation of the minimum safety factor during the vertically unstable disruption, reducing the halo current fraction and resulting vessel displacement. Both TQ and CQ characteristics are observed to saturate at relatively low quantities of neon, indicating that effective mitigation of disruption loads by shattered pellet injection (SPI) can be achieved with modest impurity quantities, within injection quantities anticipated for ITER. In conclusion, this mixed species SPI technique provides apossible approach for tuning disruption properties to remain within the limited ranges allowed in the ITER design.« less

Thermal quench mitigation and current quench control by injection of mixed species shattered pellets in DIII-D

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

Shiraki, D.; Commaux, N.; Baylor, L. R.

Injection of large shattered pellets composed of variable quantities of the main ion species (deuterium) and high-Z impurities (neon) in the DIII-D tokamak demonstrate control of thermal quench (TQ) and current quench (CQ) properties in mitigated disruptions. As the pellet composition is varied, TQ radiation fractions increase continuously with the quantity of radiating impurity in the pellet, with a corresponding decrease in divertor heating. Post-TQ plasma resistivities increase as a result of the higher radiation fraction, allowing control of current decay timescales based on the pellet composition. Magnetic reconstructions during the CQ show that control of the current decay ratemore » allows continuous variation of the minimum safety factor during the vertically unstable disruption, reducing the halo current fraction and resulting vessel displacement. Both TQ and CQ characteristics are observed to saturate at relatively low quantities of neon, indicating that effective mitigation of disruption loads by shattered pellet injection (SPI) can be achieved with modest impurity quantities, within injection quantities anticipated for ITER. In conclusion, this mixed species SPI technique provides apossible approach for tuning disruption properties to remain within the limited ranges allowed in the ITER design.« less

Thermal quench mitigation and current quench control by injection of mixed species shattered pellets in DIII-D

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

Shiraki, D.; Commaux, N.; Baylor, L. R.

Injection of large shattered pellets composed of variable quantities of the main ion species (deuterium) and high-Z impurities (neon) in the DIII-D tokamak demonstrates control of thermal quench (TQ) and current quench (CQ) properties in mitigated disruptions. As the pellet composition is varied, TQ radiation fractions increase continuously with the quantity of radiating impurity in the pellet, with a corresponding decrease in divertor heating. Post-TQ plasma resistivities increase as a result of the higher radiation fraction, allowing control of current decay timescales based on the pellet composition. Magnetic reconstructions during the CQ show that control of the current decay ratemore » allows continuous variation of the minimum safety factor during the vertically unstable disruption, reducing the halo current fraction and resulting vessel displacement. Both TQ and CQ characteristics are observed to saturate at relatively low quantities of neon, indicating that effective mitigation of disruption loads by shattered pellet injection (SPI) can be achieved with modest impurity quantities, within injection quantities anticipated for ITER. This mixed species SPI technique provides a possible approach for tuning disruption properties to remain within the limited ranges allowed in the ITER design.« less

Shattered Pellet Injection Simulations With NIMROD

NASA Astrophysics Data System (ADS)

Kim, Charlson; Parks, Paul; Lao, Lang; Lehnan, Michael; Loarte, Alberto; Izzo, Valerie; Nimrod Team

2017-10-01

Shattered Pellet Injection (SPI) will be the Disruption Mitigation System in ITER. SPI propels a cryo-pellet of high-Z and deuterium into a sharp bend of the flight tube, shattering the pellet into a plume of shards. These shards are injected into the plasma to quench it and mitigate forces and heat loads that may damage in-vessel components. We use NIMROD to perform 3-D nonlinear MHD simulations of SPI to study the thermal quench. This work builds upon prior Massive Gas Injection (MGI) studies by Izzo. A Particle-in-Cell (PIC) model is implemented to mimic the shards, providing a discrete moving source. Observations indicate that the quench proceeds in two phases. Initially, the outer plasma is shed via interchange-like instabilities while preserving the core temperature. This results in a steep gradient and triggers the second phase, an external kink-like event that collapses the core. We report on the radiation efficiency and toroidal peaking as well as fueling efficiency and other metrics that assess the efficacy of the SPI system. Work supported by GA ITER Contract ITER/CT/14/4300001108 and US DOE DE-FG02-95ER54309.

The first description and confirmation of the Vista Alegre impact structure in the Paraná flood basalts of southern Brazil

NASA Astrophysics Data System (ADS)

Crósta, Alvaro P.; Koeberl, Christian; Furuie, Rafael A.; Kazzuo-Vieira, Cesar

2010-02-01

The Vista Alegre structure, centered at 25°57'S and 52°41'W, has been recently proposed as a meteorite impact structure. The 9.5km-diameter structure is located in the Paraná state of southern Brazil, within the Paraná Basin, which contains one of the largest and most extensive flood basalt provinces on Earth. The Paraná flood basalts belong to the Serra Geral Formation and are temporally related to the opening of the South Atlantic Ocean, having been dated at about 133-132Ma. Tholeiitic basalts dominate the western portion of Paraná state, with some minor rhyodacites. Morphologically, Vista Alegre has a prominent circular outline, in the form of an incomplete ring of escarpments, and an inner depression. The presence of a central uplift is not obvious, but it is inferred by the occurrence of deformed sandstone blocks near the center of the structure. These sandstones are possibly related to the Triassic Pirambóia Formation and/or to the Cretaceous Botucatu Formation. These units are normally at stratigraphic depths of about 700-800m below the present surface in this portion of the Paraná Basin. The structure appears to be in an advanced erosion stage and its interior is occupied by a soil cover several meters thick, extensively used for agriculture. As a result there are limited outcrops in the interior of the structure, all of polymict breccias, some of them melt-bearing. We report the extensive occurrence of shatter cones, in the form of fine-grained rock clasts within the polymict breccias. The shatter cone-bearing breccias occur at different locations within the structure, separated by several kilometers. The nested shatter cones range in size from about 0.5 to 20cm for individual cones, and up to half a meter for complete assemblages. The shatter cones formed in fine-grained Parana flood basalt and might be the first examples of shatter cones in such a rock type. In addition, planar deformation features (PDFs) were found in quartz grains within sedimentary rock clasts of the polymict breccia. These findings confirm the impact origin of the Vista Alegre structure.

A new airborne sampler for interstitial particles in ice and liquid clouds

NASA Astrophysics Data System (ADS)

Moharreri, A.; Craig, L.; Rogers, D. C.; Brown, M.; Dhaniyala, S.

2011-12-01

In-situ measurements of cloud droplets and aerosols using aircraft platforms are required for understanding aerosol-cloud processes and aiding development of improved aerosol-cloud models. A variety of clouds with different temperature ranges and cloud particle sizes/phases must be studied for comprehensive knowledge about the role of aerosols in the formation and evolution of cloud systems under different atmospheric conditions. While representative aerosol measurements are regularly made from aircrafts under clear air conditions, aerosol measurements in clouds are often contaminated by the generation of secondary particles from the high speed impaction of ice particles and liquid droplets on the surfaces of the aircraft probes/inlets. A new interstitial particle sampler, called the blunt-body aerosol sampler (BASE) has been designed and used for aerosol sampling during two recent airborne campaigns using NCAR/NSF C-130 aircraft: PLOWS (2009-2010) and ICE-T (2011). Central to the design of the new interstitial inlet is an upstream blunt body housing that acts to shield/deflect large cloud droplets and ice particles from an aft sampling region. The blunt-body design also ensures that small shatter particles created from the impaction of cloud-droplets on the blunt-body are not present in the aft region where the interstitial inlet is located. Computational fluid dynamics (CFD) simulations along with particle transport modeling and wind tunnel studies have been utilized in different stages of design and development of this inlet. The initial flights tests during the PLOWS campaign showed that the inlet had satisfactory performance only in warm clouds and when large precipitation droplets were absent. In the presence of large droplets and ice, the inlet samples were contaminated with significant shatter artifacts. These initial results were reanalyzed in conjunction with a computational droplet shatter model and the numerical results were used to arrive at an improved sampler design. Analysis of the data from the recent ICE-T campaign with the improved sampler design shows that the modified version of BASE can provide shatter-artifact free sampling of aerosol particles in the presence of ice particles and significantly reduced shatter artifacts in warm clouds. Detailed design and modeling aspects of the sampler will be discussed and the sampler performance in warm and cold clouds will be presented and compared with measurements made using other aerosol inlets flown on the NCAR/NSF C-130 aircraft.

Burnout in teachers: shattered dreams of impeccable professional performance.

PubMed

Friedman, I A

2000-05-01

Burnout usually is conceptualized as a work-related syndrome stemming from the individual's perception of a significant gap between expectations of successful professional performance and an observed, far less satisfying reality. The article examines this perception as a discrepancy between expected and observed levels of the individual's professional self-efficacy. The teaching profession and its service providers--teachers--serve as a model to illustrate and support this examination. Self-reports of novice teachers' experiences in their first year of teaching are given, reflecting a world of shattered dreams of idealistic performance. Finally, a number of suggestions for programs and activities that have proven helpful in alleviating stress and burnout among teachers are described.

Surface area generation and droplet size control in solvent extraction systems utilizing high intensity electric fields

DOEpatents

Scott, Timothy C.; Wham, Robert M.

1988-01-01

A method and system for solvent extraction where droplets are shattered by a high intensity electric field. These shattered droplets form a plurality of smaller droplets which have a greater combined surface area than the original droplet. Dispersion, coalescence and phase separation are accomplished in one vessel through the use of the single pulsing high intensity electric field. Electric field conditions are chosen so that simultaneous dispersion and coalescence are taking place in the emulsion formed in the electric field. The electric field creates a large amount of interfacial surface area for solvent extraction when the droplet is disintegrated and is capable of controlling droplet size and thus droplet stability. These operations take place in the presence of a counter current flow of the continuous phase.

New Constraints on the Slate Islands Impact Structure, Ontario, Canada

NASA Technical Reports Server (NTRS)

Sharpton, Virgil L.; Dressler, Burkhard O.; Herrick, Robert R.; Schnieders, Bernie; Scott, John

1996-01-01

The Slate Islands in northern Lake Superior represent the eroded remains of a complex impact crater, originally approximately 32 km in diameter. New field studies there reveal allogenic crater fill deposits along the eastern and northern portions of the islands indicating that this 500-800 Ma impact structure is not as heavily eroded as previously thought. Near the crater center, on the western side or Patterson Island, massive blocks of target rocks, enclosed within a matrix of fine-grained polymict breccia, record the extensive deformation associated with the central uplift. Shatter cones are a common structural feature on the islands and range from less than 3 cm to over 10 m in length. Although shatter cones are powerful tools for recognizing and analyzing eroded impact craters, their origin remains poorly constrained.

Marijuana and Teens

MedlinePlus

... shatter" Having increased irritability Losing interest in and motivation to do usual activities. Spending time with peers ... trouble with physical activity, and lung cancer) Decreased motivation or interest which can lead to decline in ...

7 CFR 51.1412 - Well cured.

Code of Federal Regulations, 2010 CFR

2010-01-01

... kernel separates freely from the shell, breaks cleanly when bent, without splintering, shattering, or loosening the skin; and the kernel appears to be in good shipping or storage condition as to moisture...

Drugs: Shatter the Myths

MedlinePlus

... Health and Human Services. Table of Contents 4 Marijuana 8 Peer Pressure 12 Alcohol 14 Medical Consequences 19 Rx Drugs 22 Drugs & Your Brain 26 Treatment 3 TOPIC Marijuana Can marijuana be Yes. The chances of becoming ...

Safety shield for vacuum/pressure-chamber windows

NASA Technical Reports Server (NTRS)

Shimansky, R. A.; Spencer, R.

1980-01-01

Optically-clear shatter-resistant safety shield protects workers from implosion and explosion of vacuum and pressure windows. Plastic shield is inexpensive and may be added to vacuum chambers, pressure chambers, and gas-filling systems.

On the Couch

ERIC Educational Resources Information Center

Mack, Ed

1972-01-01

Two parts of reading control the pedagogy: statistics and curriculum development. One uses math; the other, the noun. Both live in the twilight of madness." A myth-shattering critique of current practices in the teaching of Reading. (Author/RY)

The Case of Norway - Spectacular Renegades from Central Control

ERIC Educational Resources Information Center

Belding, Robert E.; Lane, Willard R.

1975-01-01

Education in Norway's far northlands is wonderfully diverse, even though local schools are governed by a national ministry of education. This article should shatter the myth that central control means bland homogenization. (Editor)

Characteristics of Whipple Shield Performance in the Shatter Regime

NASA Technical Reports Server (NTRS)

Ryan, Shannon; Bjorkman, Michael; Christiansen, Eric L.

2009-01-01

Between the onset of projectile fragmentation and the assumption of rear wall failure due to an impulsive load, multi-wall ballistic limit equations are linearly interpolated to provide reasonable yet conservative predictions of perforation thresholds with conveniently simple mathematics. Although low velocity and hypervelocity regime predictions are based on analytical expressions, there is no such scientific foundation for predictions in the intermediate (or shatter) regime. As the debris flux in low earth orbit (LEO) becomes increasingly dominated by manmade pollution, the profile of micrometeoroid and orbital debris (MMOD) risk shifts continually towards lower velocities. For the International Space Station (ISS), encounter velocities below 7 km/s now constitute approximately 50% of the penetration risk. Considering that the transition velocity from shatter to hypervelocity impact regimes described by common ballistic limit equations (e.g. new non-optimum Whipple shield equation [1]) occurs at 7 km/s, 50% of station risk is now calculated based on failure limit equations with little analytical foundation. To investigate projectile and shield behavior for impact conditions leading to projectile fragmentation and melt, a series of hypervelocity impact tests have been performed on aluminum Whipple shields. In the experiments projectile diameter, bumper thickness, and shield spacing were kept constant, while rear wall thickness was adjusted to determine spallation and perforation limits at various impact velocities and angles. The results, shown in Figure 1 for normal and 45 impacts, demonstrated behavior that was not sufficiently described by the simplified linear interpolation of the NNO equation (also shown in Figure 1). Hopkins et al. [2] investigated the performance of a nominally-identical aluminum Whipple shield, identifying the effects of phase change in the shatter regime. The results (conceptually represented in Figure 2) were found to agree well with those obtained in this study at normal incidence, suggesting that shielding performance in the shatter regime could be well described by considering more complex phase conditions than currently implemented in most BLEs. Furthermore, evidence of these phase effects were found in the oblique test results, providing the basis for an empirical description of these effects that can be applied in MMOD risk assessment software. In this paper, results of the impact experiments are presented, and characteristics of target damage are evaluated. A comparison of intermediate velocity impact failure mechanisms in current BLEs are discussed and compared to the findings of the experimental study. Risk assessment calculations have been made on a simplified structure using currently implemented penetration equations and predicted limits from the experimental program, and the variation in perceived mission risk is discussed. It was found that ballistic limit curves that explicitly incorporated phase change effects within the intermediate regime lead to a decrease in predicted MMOD risk for ISS-representative orbits. When considered for all Whipple-based shielding configurations onboard the ISS, intermediate phase change effects could lead to significant variations in predicted mission risk.

Women's Career Development at the Glass Ceiling.

ERIC Educational Resources Information Center

Inman, Pamela L.

1998-01-01

For women, success in shattering the glass ceiling lies not in adapting to a male workplace culture but in using career strategies such as self-knowledge, multiple mentors, integration of body and soul, and fluid, customized careers. (SK)

Larsen B Ice Shelf

Atmospheric Science Data Center

2013-04-16

article title:  Unique Views of a Shattered Ice Shelf     View Larger Image ... views of the breakup of the northern section of the Larsen B ice shelf are shown in this image pair from the Multi-angle Imaging ...

The preservation of the Agoudal impact crater, Morocco, under a landslide: Indication of a genetic link between shatter cones and meteorite fragments

NASA Astrophysics Data System (ADS)

Nachit, Hassane; Abia, El Hassan; Bonadiman, Costanza; Di Martino, Mario; Vaccaro, Carmela

2017-10-01

Geological studies and tomographic profiles of a locality nearby the Agoudal village (Morocco) showed the presence of a single impact crater, 500-600 m diameter, largely hidden by a limestone block, 220 m long and 40 m deep. The site was interpreted as a landslide that followed the fall of a cosmic body. The Agoudal impact crater was not affected by intense erosion. The lack of an evident impact structure, as well as the sporadic distribution of impactites and their limited occurrence, can be explained by a complex geological framework and by recent tectonics. The latter is the result of the sliding of limestone block, which hides almost two-thirds of the crater's depression, and the oblique fall of the meteoroid on sloping ground. In addition, some impact breccia dikes sharply cut the host rock in the Agoudal impact structure. They do not show any genetic relationship with tectonics or hydrothermal activity, nor are they related to any karst or calcrete formations. Altogether, the overlapping of the meteorite strewn field (11 km long and 3 km wide) with the area of occurrence of shatter cones and impact breccias, together with the presence of meteorite fragments (shrapnel) ejected from the crater, the presence of shatter cones contaminated by products of iron meteorites and the presence of impact breccias that contain meteorite fragments of the same chemical composition of the Agoudal meteorite indicate that the fall of this meteorite can be responsible for the formation of the impact structure.

Broken rims in railroad wheels.

DOT National Transportation Integrated Search

2014-12-01

Broken wheels are one of the most common types of equipment-caused train accidents. The failure of rail car wheel rims, which : are usually the result of shattered rims or vertical split rims (VSR), are the leading cause of wheel-related accidents, a...

Human Trafficking. Ministering to The 'Invisible' Victim.

PubMed

Scanlon, Colleen; Krausa, Laura

2016-07-01

Human trafficking is modern-day slavery - an insidious, criminal industry that gener- ates billions of dollars in labor trafficking alone. It knows no boundary of continent, country, race or class; it is a shattering, impartial predator that robs individuals of their basic human dignity.

16 CFR 1500.86 - Exemptions from classification as a banned toy or other banned article for use by children.

Code of Federal Regulations, 2010 CFR

2010-01-01

...; will not shatter, crack, or chip; is free of cracks, flash (ridges due to imperfect molding), and... paragraph from classification as a banned hazardous substance. (6) Caps (paper or plastic) described in...

The Tin Bider Impact Structure, Algeria: New Map with Field Inputs on Structural Aspect

NASA Astrophysics Data System (ADS)

Kassab, F.; Belhai, D.

2017-07-01

The Tin Bider impact structure is a complex type composed by sedimentary target rocks. We realized a geological map including new inputs on impact characters of a recent field investigation where we identify shatter cone and folds.

A Modest Manifesto for Shattering the Glass Ceiling.

ERIC Educational Resources Information Center

Meyerson, Debra E.; Fletcher, Joyce K.

2000-01-01

Approaches to the glass ceiling--encouraging women to adopt "masculine" attributes, accommodating women's unique needs, or celebrating women's differences--have shortcomings. A fourth approach links equity and effectiveness. "Small wins" recognizes that gender inequity is rooted in cultural patterns and uses small initiatives…

The mesoproterozoic Beaverhead impact structure and its tectonic setting, Montana-Idaho: 40Ar/39 and U-Pb isotopic constraints

USGS Publications Warehouse

Kellogg, K.S.; Snee, L.W.; Unruh, D.M.

2003-01-01

New 40Ar/39Ar and uranium-lead (U-Pb) zircon data from the Beaverhead impact structure, first identified by extensive shatter coning of Proterozoic quartzite and gneiss from the Beaverhead Mountains near the Montana-Idaho border, indicate that the structure formed at or after 900 Ma. The 40Ar/39Ar age spectra from fine-grained muscovite and biotite from a breccia zone in high-grade gneiss show significant argon loss but yield dates for highest-temperature steps that cluster between 899 and 908 Ma. The dated minerals probably formed by recrystallization of impact glass, so on both geologic and isotopic grounds, the dates probably represent the minimum age of impact. U-Pb data for zircons from the same breccia are strongly discordant and yield an upper intercept apparent age of 2464 ?? 56 Ma and a lower intercept apparent age of 779 ?? 69 Ma. Another brecciated gneiss about 7 km to the northeast that does not contain secondary mica does contain zircons that yield a concordant apparent age of 2455 ?? 9 Ma. Nearby gneiss that neither is brecciated nor contains shatter cones yields an apparent age of 2451 ?? 46 Ma. The 40Ar/39Ar results constrain the age of the shatter-coned quartzite and indicate that it is >900 Ma and possibly correlative with the Gunsight Formation of the Mesoproterozoic Lemhi Group. The upper intercept U-Pb age of ???2450 Ma from all three dated samples also shows that the Paleoproterozoic basement rocks of the area are among the youngest in the mostly Archean Wyoming province of North America. The impact site lies near the margin of the province, along the northeast-trending Great Falls tectonic zone, and the relatively young crustal age may reflect Early Proterozoic marginal accretion.

The Shattered Stereotype: The Academic Library in Technological Transition.

ERIC Educational Resources Information Center

Foster, Constance L.

In academic libraries, neither technical services, public services, nor administration has escaped the impact of online information systems. Online catalogs, network systems, interlibrary lending, database searches, circulation control, automated technical processes, and an increasing number of non-book materials are part of a technological…

DoD Contractors’ Safety Manual for Ammunition and Explosives.

DTIC Science & Technology

1997-09-01

grit, and other foreign material into operating buildings. 9. Windows and skylights . Non-shatterable glazing is preferred where an explosion...with the explosives being processed. Dull or damaged tools shall not be used for machining high explosives. k. The explosives products resulting from

Cortex shatters the glass ceiling.

PubMed

Au, Edmund; Fishell, Gord

2008-11-06

Recreating developmental structures in vitro has been a primary challenge for stem cell biologists. Recent studies in Cell Stem Cell (Eiraku et al., 2008) and Nature (Gaspard et al., 2008) demonstrate that embryonic stem cells can recapitulate early cortical development, enabling them to generate specific cortical subtypes.

PRB rail loadings shatter record

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

Buchsbaum, L.

Rail transport of coal in the Powder River Basin has expanded, with a record 2,197 trains loaded in a month. Arch Coal's Thunder basin mining complex has expanded by literally bridging the joint line railway. The dry fork mine has also celebrated its safety achievements. 4 photos.

Rhetorics of Resistance.

ERIC Educational Resources Information Center

Allen, Julia M.

A critical rhetoric is needed for those interested in feminist discourse, a means of both persuasion and critique. It has been suggested that monologic, fundamentally one-sided argument is inappropriate for a feminist discourse that should instead teach methods of negotiation and mediation. Kenneth Burke proposed shattering views of ideological…

Safety shield for vacuum/pressure chamber viewing port

NASA Technical Reports Server (NTRS)

Shimansky, R. A.; Spencer, R. S. (Inventor)

1981-01-01

Observers are protected from flying debris resulting from a failure of a vacuum or pressure chamber viewing port following an implosion or explosion by an optically clear shatter resistant safety shield which spaced apart from the viewing port on the outer surface of the chamber.

36 CFR Appendix A to Part 1234 - Minimum Security Standards for Level III Federal Facilities

Code of Federal Regulations, 2014 CFR

2014-07-01

... technology and blast standards. Immediate review of ongoing projects may generate savings in the... critical systems (alarm systems, radio communications, computer facilities, etc.) Required. Occupant... all exterior windows (shatter protection) Recommended. Review current projects for blast standards...

36 CFR Appendix A to Part 1234 - Minimum Security Standards for Level III Federal Facilities

Code of Federal Regulations, 2013 CFR

2013-07-01

... construction projects should be reviewed if possible, to incorporate current technology and blast standards... critical systems (alarm systems, radio communications, computer facilities, etc.) Required. Occupant... all exterior windows (shatter protection) Recommended. Review current projects for blast standards...

36 CFR Appendix A to Part 1234 - Minimum Security Standards for Level III Federal Facilities

Code of Federal Regulations, 2012 CFR

2012-07-01

... technology and blast standards. Immediate review of ongoing projects may generate savings in the... critical systems (alarm systems, radio communications, computer facilities, etc.) Required. Occupant... all exterior windows (shatter protection) Recommended. Review current projects for blast standards...

The Shattered Humanities.

ERIC Educational Resources Information Center

Bennett, William J.

Intellectual refinement and spiritual evaluation have been the traditional goals of the humanities and should remain so. If these aims are given up, then the noble endeavors in the humanities such as sustained reflection, intensive research, careful scholarship, inspired teaching, deep learning, and serious discussion will all become discredited…

Mechanical properties of acacia and eucalyptus wood chars

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

Kumar, M.; Verma, B.B.; Gupta, R.C.

1999-10-01

In the present investigation the effects of carbonization conditions (temperature and heating rate) on the mechanical properties (such as crushing and impact strengths and shatter index) of acacia and eucalyptus wood chars have been determined. The crushing and impact strengths of both the acacia and eucalyptus wood chars (made by slow carbonization) decreased with increase of preparation temperature up to 600 C, followed by an increase thereafter. These wood chars showed a continuous increase in shatter index values with carbonization temperature. In contrast to slow carbonization (heating rate 4 C min{sup {minus}1}), rapid carbonization (heating rate 30 C min{sup {minus}1})more » yielded chars of lower crushing strengths. Slowly carbonized eucalyptus wood gave chars of superior crushing and impact strengths than those produced from acacia wood under the same carbonization conditions. The crushing and impact strengths of these wood chars, in general, have shown an increase with increase in their apparent density. The crushing strength of cubic-shaped wood char decreased with increase in size.« less

The Warsaw Ghetto: A Shattered Window on the Holocaust.

ERIC Educational Resources Information Center

Burstin, Barbara Stern

1980-01-01

Reviews literature about the Warsaw ghetto uprising in April, 1943, in which Jewish resistance fighters fought to the last against the Nazi war machine. The author notes that history textbooks at both high school and college levels give virtually no mention of the revolt. (Author/KC)

Shattering Myths: Japanese American Educational Issues.

ERIC Educational Resources Information Center

Yoshiwara, Florence M.

An historical review of the immigration and resettlement patterns, and a demographic profile of Japanese Americans reveals a myth of the "successful minority." Since the founding of the Japanese American Citizens League in 1928, Japanese Americans have defeated alien land laws, discriminatory immigration quotas, anti-miscengenation laws,…

Neurotic and Environmental Sources of Psychotherapist Resistance to Evaluation.

ERIC Educational Resources Information Center

Van Atta, Ralph

Observation of the treatment process and outcomes research may interfere with self-gratifications and may shatter illusions about a therapist's omnipotence. Consequently, research and evaluation must be understood to threaten, inherently, personal need gratification of therapists. The author discusses several reality-based therapist objections to…

Biobased lubricants and functional products from Cuphea oil

USDA-ARS?s Scientific Manuscript database

Cuphea (Lythraceae) is an annual plant that produces a small seed rich in saturated medium-chain triacylglycerols (TAGs). With the need for higher seed yields, oil content, and less seed shattering, Oregon State University began developing promising cuphea crosses. Cuphea PSR23 is a hybrid between C...

Navigating the Labyrinth

ERIC Educational Resources Information Center

Eagly, Alice H.; Carli, Linda L.

2009-01-01

The glass ceiling has shattered. The metaphor of a glass ceiling, an absolute barrier to women's advancement, is seriously outdated. Some women do make it to high positions as big-city superintendents of schools, governors, secretaries of state and, even occasionally, as Fortune 500 CEOs. The glass ceiling metaphor has great appeal but is…

Fragmented Economy, Stratified Society, and the Shattered Dream

ERIC Educational Resources Information Center

Mordechay, Kfir

2011-01-01

Across the massive megalopolis stretching from the northern suburbs of Los Angeles County through the metropolitan complex along the northern border of Baja California is a diverse area containing 24 million people, with a disproportionate percentage of Latinos and African Americans who are facing an educational and economic disaster. As it…

Special Course on Advances in Cryogenic Wind Tunnel Technology

DTIC Science & Technology

1989-06-09

shatter. However, in the finely divided form of fibres, powders, films, foams and expanded granules they are widely used for thermal and electrical...it is inevitable that the lecture will also have something of the flavour of a research report. 2. Remurements (i) Aerodynamic An important requirement

Communicating with the Elderly: Shattering Stereotypes.

ERIC Educational Resources Information Center

Freimuth, Vicki S.; Jamieson, Kathleen

Designed to present communications problems faced by the elderly and to assist classroom teachers to develop activities for dealing with them, this booklet begins by examining stereotypes of older persons which minimize and distort communication with them. It outlines common misconceptions about the elderly, centering on their state of mind,…

Shattering the Glass Ceiling: Women in School Administration.

ERIC Educational Resources Information Center

Patterson, Jean A.

Consistent with national trends, white males hold the majority of public school administrator positions in North Carolina. This paper examines the barriers and underlying assumptions that have prevented women and minorities from gaining access to high-level positions in educational administration. These include: (1) the assumption that leadership…

The impact of volunteer rice infestation on rice yield and grain quality

USDA-ARS?s Scientific Manuscript database

Volunteer rice (Oryza sativa L.) is a crop stand which emerges from shattered seeds of the previous crop. When present at sufficiently high levels, it can potentially affect the commercial market value of cultivated rice products, especially if it produces kernels with quality, uniformity, or size ...

Scientific Research: Commodities or Commons?

ERIC Educational Resources Information Center

Vermeir, Koen

2013-01-01

Truth is for sale today, some critics claim. The increased commodification of science corrupts it, scientific fraud is rampant and the age-old trust in science is shattered. This cynical view, although gaining in prominence, does not explain very well the surprising motivation and integrity that is still central to the scientific life. Although…

Victimization Status and Perceived Risk of Sexual Assault: Longitudinal Analyses.

ERIC Educational Resources Information Center

White, Jacquelyn W.; Humphrey, John A.

Even though rape is the crime they fear most, women hold strong beliefs that their personal risk for sexual victimization is lower than the risk for other women. Victimization shatters illusions of invulnerability, and results in feelings of vulnerability, suggesting that sexual victimization should decrease women's perceived invulnerability for…

Foreign Students Pour Back into the U.S.

ERIC Educational Resources Information Center

McMurtrie, Beth

2008-01-01

This article reports that the number of international students enrolled in American colleges in the fall of 2007 shattered previous records and represents the largest one-year increase in decades, according to new data from the Institute of International Education. Educators and government officials say the bounce indicates that hostile…

You Go, Girl! Shape Up, Slim Down, Shatter the Stereotype

ERIC Educational Resources Information Center

Belben, Cathy

2004-01-01

As a profession librarians are stereotyped as frequently as engineers and accountants--if not more so. They are bifocal-wearing bunheads, collectors of cardigan sweaters, middle-aged women in polyester suits, Naturalizer shoes, and baggy stockings. Besides being fashion disasters, librarians are generally thought of as being exceptionally unsexy,…

Juanita Fights the School Board.

ERIC Educational Resources Information Center

Velasquez, Gloria

This book relates the fictional story of Juanita Chavez, a Mexican-American teenager who unjustly faces expulsion from school after fighting with a White student who was spreading rumors about her family. Juanita knows that if she is expelled this will greatly disappoint her parents and shatter her dream of becoming the first one in her family to…

Professional Expectations and Shattered Dreams: A Proficiency Dilemma

ERIC Educational Resources Information Center

Fischer, Gerhard

2013-01-01

In this article the author asserts that learning is about personal growth and enrichment, and at its core it is not about career determinations. Good teachers nurture their students; they encourage them to pursue their dreams, and they find ways to stimulate curiosity and dedication to lifelong learning. They do not become teachers because of…

Shattering the Glass Ceiling: Blacks in Coaching

ERIC Educational Resources Information Center

Hill, Fitzgerald

2004-01-01

During the 2003 football season, African Americans were employed as head coaches at five of the 117 NCAA Division I-A colleges and universities. At the conclusion of the 2003 season, there were 13 head coaching vacancies at Division I-A football programs; one African American was hired. Today, five African Americans have the responsibility of…

Overcoming Heartbreak: Learning to Make Music Again

ERIC Educational Resources Information Center

Vogel, Joanne Elise

2005-01-01

As a universal theme, love touches each of our lives in different and unique ways. This manuscript addresses the often overlooked sense of grief and loss that occurs when our dreams of love are shattered. It also addresses how addiction and commitment conflicts impede intimacy and loving relationships. While movies, music, and books offer many…

Effect of volunteer rice infestation on grain quality and yield of rice

USDA-ARS?s Scientific Manuscript database

Volunteer rice (Oryza sativa L.) plants arise from shattered seeds of the previous crop, which could reduce the yield of cultivated rice and the commercial value of harvested grain. Volunteer rice plants from a cultivar other than the current crop produce grains that may differ in physico-chemical t...

Genetic Dissection of Seed Production Traits and Identification of a Major-Effect Seed Retention QTL in Hybrid Leymus (Triticeae) Wildryes

USDA-ARS?s Scientific Manuscript database

Many native grasses display seed shattering and other seed production problems. Basin wildrye (Leymus cinereus) and creeping wildrye (L. triticoides) are perennial Triticeae grasses native to western North America. In this study, variation in the number of florets per inflorescence, percent seed s...

Jagged Edges of the Glass Ceiling

ERIC Educational Resources Information Center

Robinson, Victoria L.

2004-01-01

Although many aspiring young women might believe the glass ceiling was shattered a decade ago, they still need to understand how that glass ceiling impacted an older generation of women in educational leadership. They also must be aware that some segments of the glass ceiling might still exist. This article provides a historical overview of the…

Dreams Fulfilled, Dreams Shattered: Determinants of Segmented Assimilation in the Second Generation

ERIC Educational Resources Information Center

Haller, William; Portes, Alejandro; Lynch, Scott M.

2011-01-01

We summarize prior theories on the adaptation process of the contemporary immigrant second generation as a prelude to presenting additive and interactive models showing the impact of family variables, school contexts and academic outcomes on the process. For this purpose, we regress indicators of educational and occupational achievement in early…

Tragedy at Virginia Tech: Trauma and Its Aftermath

ERIC Educational Resources Information Center

Flynn, Christopher; Heitzmann, Dennis

2008-01-01

While college campuses are relatively safe environments, the promise of safety and security on campus was shattered by a single gunman on April 16, 2007. Seung-Hui Cho, a senior at Virginia Tech, shot 49 students and faculty, killing 32, before killing himself. The authors are psychologists and directors of university counseling centers; they…

Relationships within the Shattered Rainbow: A Search for a Pedagogy of Attunement

ERIC Educational Resources Information Center

Blades, Genny; Bester, Lucas

2013-01-01

This paper explores "relationships with others" in outdoor environmental education through a search for a pedagogy of attunement, which we propose is a relational-responsive pedagogy. We have primarily drawn from Martin Buber's philosophy of dialogue and its pedagogical significance. Buber offers insights into articulating the…

Bodies that Shatter: Creativity, Culture and the New Pedagogical Imaginary

ERIC Educational Resources Information Center

Harris, Anne; Lemon, Andrea

2012-01-01

Taking Butler's notion of embodied performativity in relation to education and global flow, this article uses one example of Samoan cultural dance within a community arts education programme to argue the need for localised, context- and culture-specific arts pedagogies which incorporate diversity in all its expressions, suggest an emerging…

Student Athletes: Shattering the Myths & Sharing the Realities.

ERIC Educational Resources Information Center

Kirk, Wyatt D., Ed.; Kirk, Sarah V., Ed.

This book covers the developmental benefits of athletics. It provides a step-by-step model for setting up a comprehensive high school program, a guide for college-bound athletes, seven case studies, and an outline of counselors' responsibilities. The book is divided into three major parts: the athletic environment and the athlete's participation…

The Battle of Glorieta Pass: A Shattered Dream. Teaching with Historic Places.

ERIC Educational Resources Information Center

McBride, James; Reed, Judy

Henry Hopkins Sibley shared his nation's destiny of spanning the American continent from the Atlantic to the Pacific. Sibley's nation was the Confederate States of America, and Confederate President Jefferson Davis shared Sibley's vision of southern manifest destiny. President Davis authorized Sibley to raise volunteers for the Confederate Army of…

Managing Threats: Examining Intra-Organizational Collaboration between Academic and Student Affairs Divisions

ERIC Educational Resources Information Center

Chinn, Mignon N.

2013-01-01

Tragic shootings in classrooms on the campuses of Virginia Tech (2007), Louisiana Technical College (2008), and Northern Illinois University (2008) where 39 students and faculty members lost their lives shattered perceptions of the college campus as a safe haven (Dungy & Roberts, 2010), brought heightened awareness to the decade-long increase…

Army Strong, Superintendent Savvy

ERIC Educational Resources Information Center

Mellon, Ericka

2011-01-01

Brigadier General Anthony "Tony" Tata of the U.S. Army had one of those "ah-ha" moments in April 2006 when, on the eve of an operation he was heading in Afghanistan, an Al Qaeda rocket shattered a nearby school. The attack killed a teacher and seven students and wounded dozens more. The rocket incident eventually nudged Tata…

Defense Science Board 2006 Summer Study on 21st Century Strategic Technology Vectors. Volume 1: Main Report

DTIC Science & Technology

2007-02-01

understand forms to military personnel and monolingual English-speaking analysts in response to direct or implicit requests. Human, Social, Cultural, and... dictionary defines “disruptive” as the adjective form of the verb disrupts, which means to interrupt, separate forcefully, or shatter. In application to

A Shattering Epiphany in James Joyce's "Araby"

ERIC Educational Resources Information Center

Rokeya, Ms.; Ahammed, A.K. Zunayet

2017-01-01

This article attempts to show an adolescent boy's continuing process of self-realisation through his disillusionment with the bleak reality of Dublin in the early twentieth century in the short story "Araby" by James Joyce. Brought up in the drab and deadening surroundings with his uncle and aunt in conservative Catholic cultures, the…

Dust Coagulation in Infalling Protostellar Envelopes I. Compact Grains

NASA Technical Reports Server (NTRS)

Yorke, H.; Suttner, G.; Lin, D.

1999-01-01

Dust plays a key role in the optical, thermodynamic and gas dynamical behavior of collapsing molecular cores. Because of relative velocities of the individual dust grains, coagulation and shattering can modify the grain size distribution and due to corresponding changes in the medium's opacity significantly influence the evolution during early phase of star formation.

Dust Coagulation in Infalling Protostellar Envelopes I. Compact Grains

NASA Technical Reports Server (NTRS)

Yorke, H.; Lin, D.; Suttner, G.

1999-01-01

Dust plays a key role in the optical, thermodynamic and gas dynamical behavior of collapsing molecular cores. Because of relative velocities of the individual dust grains, coagulation and shattering can modify the grain size distribution and -- due to corresponding changes in the medium's opacity significantly -- influence the evolution during early phases of star formation.

Collapse of Monopoly Privilege: From College to University

ERIC Educational Resources Information Center

Davidovitch, Nitza; Soen, Dan; Iram, Yaacov

2008-01-01

This article focuses on the erosion of the monopoly by universities of the higher education system in Israel. The hegemony of the universities, the major player in the academic field, has been shattered by the development of the regional colleges that unsettled the preconceptions concerning the higher education system in Israel, including the…

Development of a novel Sinapis arvensis disomic addition line in Brassica napus containing the restorer gene for Nsa CMS and improved resistance to Sclerotinia sclerotiorum and pod shattering.

PubMed

Wei, Wenhui; Li, Yunchang; Wang, Lijun; Liu, Shengyi; Yan, Xiaohong; Mei, Desheng; Li, Yinde; Xu, Yusong; Peng, Pengfei; Hu, Qiong

2010-04-01

An allo-cytoplasmic male sterile line, which was developed through somatic hybridization between Brassica napus and Sinapis arvensis (thus designated as Nsa CMS line), possesses high potential for hybrid production of rapeseed. In order to select for restorer lines, fertile plants derived from the same somatic hybridization combination were self-pollinated and testcrossed with the parental Nsa CMS line for six generations. A novel disomic alien addition line, B. napus-S. arvensis, has been successfully developed. GISH analysis showed that it contains one pair of chromosomes from S. arvensis and 19 pairs from B. napus, and retains stable and regular mitotic and meiotic processes. The addition line displays very strong restoration ability to Nsa CMS line, high resistance to Sclerotinia sclerotiorum and a low incidence of pod shattering. Because the addition line shares these very important agricultural characters, it is a valuable restorer to Nsa CMS line, and is named NR1 here (Nsa restorer no. 1).

Importance of an intact dura in management of compound elevated fractures; a short series and literature review.

PubMed

Mohindra, Sandeep; Singh, Harnarayan; Savardekar, Amey

2012-01-01

To describe compound elevated fractures (CEFs) of the skull vault, with radiological pictures, management problems and prognosticative factors. The authors describe three cases of CEFs of the cranium, their mode of injury, clinical findings, radiological images and management problems. The authors have reviewed the existing literature regarding epidemiological data, neurological status, dural breech, methods of management and final outcome, in respect of CEFs. The first case had no dural breech, the second case had completely shattered dura, with extruding brain matter from the wound, while the third case had an elevated bone flap in consequence to large extradural haematoma. The patients with intact dura had relatively favourable outcome, when compared to patients with shattered dura. Three cases are added to the existing 10 such cases described in English literature. The major cause of unfavourable outcome remains sepsis and the presence of intact dura places these cases in the relatively safe category, regarding infective complications. The authors attempt at highlighting the importance of intact dura with such an injury. The review of literature supports favourable outcomes in patients having no dural breech.

Drawing lines and borders: how the dehiscent fruit of Arabidopsis is patterned.

PubMed

Dinneny, José R; Yanofsky, Martin F

2005-01-01

The advent of fruits marked a key innovation in the evolution of flowering plants and helped generate a diverse array of mechanisms for seed dispersal. In the model plant, Arabidopsis thaliana, seed dispersal occurs through a process known as "pod-shatter" in which the fruit structure falls to pieces upon light mechanical pressures. This dispersal mechanism is dependent on the careful patterning of tissues in the fruit, which perform diverse functions that enable the fruit to open at maturation. Using the genetic power of Arabidopsis, many of the molecular components that help specify these tissues have been identified. Studies of the interactions among these genes have revealed a regulatory network that limits processes such as cell-cell separation and lignification to discreet regions of the fruit. Knowledge of these processes in a model fruit creates a foundation on which to build an understanding of the evolution of fruit form in other species and provides tools to engineer shatter-resistant seed pods to prevent crop loss in plants of agronomic importance such as canola. Copyright 2004 Wiley Periodicals, Inc.

Search for a meteoritic component at the Beaverhead impact structure, Montana

NASA Technical Reports Server (NTRS)

Lee, Pascal; Kay, Robert W.

1992-01-01

The Beaverhead impact structure, in southwestern Montana, was identified recently by the presence of shatter cones and impactites in outcrops of Proterozoic sandstones of the Belt Supergroup. The cones occur over an area greater than 100 sq km. Because the geologic and tectonic history of this region is long and complex, the outline of the original impact crater is no longer identifiable. The extent of the area over which shatter cones occur suggests, however, that the feature may have been at least 60 km in diameter. The absence of shatter cones in younger sedimentary units suggests that the impact event occurred in late Precambrian or early Paleozoic time. We have collected samples of shocked sandstone from the so-called 'Main Site' of dark-matrix breccias, and of impact breccias and melts from the south end of Island Butte. The melts, occurring often as veins through brecciated sandstone, exhibit a distinctive fluidal texture, a greenish color, and a cryptocrystalline matrix, with small inclusions of deformed sandstone. Samples of the same type, along with country rock, were analyzed previously for major- and trace-element abundances. It was found that, although the major-element composition as relatively uniform, trace-element composition showed variations between the melt material and the adjacent sandstone. These variations were attributed to extensive weathering and hydrothermal alteration. In a more specific search for a possible meteoritic signature in the breccia and the melt material we have conducted a new series of trace-element analyses on powders of our own samples by thermal neutron activation analysis. Our results indicate that Ir abundances in the breccia, the melts, and the adjacent sandstone clasts are no greater than about 0.1 ppb, suggesting no Ir enrichment of the breccia or the melts relative to the country rock. However, both the breccia and the melt material exhibit notable enrichments in Cr (8- and 10-fold), in U (9- and 5-fold), and in the heavy REE's (1.5- and 3-fold), respectively.

Tacit Knowledge in Trust Development: First Year Efforts of Two Newly-Hired Superintendents.

ERIC Educational Resources Information Center

Nestor-Baker, Nancy; Tschannen-Moran, Megan

Most people know much more than they can communicate because their personal knowledge is so thoroughly grounded in experience that it cannot be expressed in its fullness. This study examines how two superintendents used tacit knowledge to build shattered trust in their school boards. Trust is first examined as a multifaceted aspect of human…

Los Angeles School Board Race Shatters Spending Records

ERIC Educational Resources Information Center

Maxwell, Lesli A.

2013-01-01

The price tag to win a seat in this week's primary election for the Los Angeles school board climbed to unprecedented levels, as a massive influx of outside cash has turned a local campaign into a national showdown pitting the long-standing influence of teachers' unions against the expanding imprint of deep-pocketed education activists. The high…

Red Tape, Silver Hammers, & Shattered Ashtrays: What States and Communities Can Learn from Eight Years of Federal Reinvention.

ERIC Educational Resources Information Center

Sylvester, Kathleen; Umpierre, Michael

This report presents lessons learned from the National Partnership for Reinventing Government (NPR) and offers advice for state and local reinvention efforts, describing how NPR's leaders built political and public support and focusing on five aspects of reinvention: getting started (e.g.; creating a reinvention team, building relationships with…

Starting School: The Importance of Parents' Expectations

ERIC Educational Resources Information Center

Russell, Fran

2005-01-01

Following the diagnosis of a child's disability parents can find that their expectations are shattered. As they adjust to their new situation they will begin to develop new ideas of what the future will hold. Supporting families is a key theme in current government policy, hence the development of the Early Support Programme. In this paper Fran…

Breaking the Glass Ceiling of Achievement for Low-Income Students and Students of Color. Shattering Expectations Series

ERIC Educational Resources Information Center

Bromberg, Marni; Theokas, Christina

2013-01-01

Typically, achievement gaps between groups of students are measured as either differences in average scores or differences in proficiency rates. But, practitioners, policymakers, and researchers have long recognized that these approaches don't tell the whole story. Average scores, for example, are good at summarizing trends but can mask real…

Carpe Diem: Seizing the Opportunity in the Arctic with a Comprehensive U.S. Arctic Strategy

DTIC Science & Technology

2008-07-01

Shatters All Previous Record Lows," press release, Oct. 1, 2007. http://www.nsidc.org/news/press/2007_seaiceminimum 7 Rune G Graversen, Thorsten Mauritsen...James. "Fight for the Top of the World." Time, Oct 1 2007,28. Graversen, Rune G., Thorsten Mauritsen, Michael Tjernstrom, Erland Kallen, Gunilla

Breakthrough: The Career Woman's Guide to Shattering the Glass Ceiling.

ERIC Educational Resources Information Center

Flanders, Margaret L.

This practical guide for all working women shows the reader how to recognize the barriers likely to confront her and to find the most effective way of breaking through. Chapter 1 summarizes causes of the glass ceiling and provides pointers on recognizing which situations are likely to cause problems. Chapter 2 helps the reader to understand her…

A technique for breaking ice in the path of a ship

NASA Technical Reports Server (NTRS)

Saunders, A. R.; Hess, R. V.; Lucht, R. A. (Inventor)

1972-01-01

A technique is described for breaking ice in the path of a ship. A laser is placed on the bow of the ship with apparatus to scan the ice in the path of the ship with the laser beam. The beam cuts or shatters the ice, enabling the ship to break the ice in its path.

Shattering the Glass Ceiling: The Woman Manager.

ERIC Educational Resources Information Center

Davidson, Marilyn J.; Cooper, Cary L.

This book highlights the major problems and stressors of being a woman in business and management and outlines some strategies that women managers can use to eliminate barriers and break through the glass ceiling. Chapter 1 provides an overview of women in management and business in the 1990s. Chapter 2 explores the nature of stress, costs of…

Follow the Leader: A Proposal to Make Whole of Government Global Engagement Work

DTIC Science & Technology

2009-06-12

fragmented control over global information across all topics - social , economic and political, shattering one of the central unifying factors in the ...Science Degree in Joint Campaign Planning and Strategy. The contents of this paper reflect my own personal views and are not necessarily endorsed by...Distinction .................................................. 53 Leadership from the Start : Operationalizing Consensus

Safe Schools: A Best Practices Guide

ERIC Educational Resources Information Center

Council of Educational Facility Planners International, 2013

2013-01-01

Every day in America more than 50 million children go to neighborhood public schools. Parents send them off with every hope they will be safe while there. And yet, as has been the case in too many cities, violence shatters that hope. The Council of Educational Facilities Planners International (CEFPI) seeks to lead in the effort to bolster schools…

The Strange World of Classical Physics

ERIC Educational Resources Information Center

Green, David

2010-01-01

We have heard many times that the commonsense world of classical physics was shattered by Einstein's revelation of the laws of relativity. This is certainly true; the shift from our everyday notions of time and space to those revealed by relativity is one of the greatest stretches the mind can make. What is seldom appreciated is that the laws of…

Supervision Groups at a Time of Violent Social Conflict in Israel

ERIC Educational Resources Information Center

Nuttman-Shwartz, Orit; Shay, Sarit

2006-01-01

Beginning in September 2000, terror attacks and large numbers of casualties became part of Israel's harrowing daily routine. The attacks occurred throughout the country, putting everyone at risk. These events also shattered the illusion of coexistence between Jewish and Arab citizens of Israel and led to feelings of anger and suspicion between the…

Not Learning in the Workplace: Austerity and the Shattering of "Illusio" in Public Service

ERIC Educational Resources Information Center

Colley, Helen

2012-01-01

Purpose: This paper seeks to discuss the impact of UK government austerity policies on learning in public service work, specifically youth support work. It also aims to argue that austerity policies intensify "ethics work", create emotional suffering, and obstruct workplace learning in a variety of ways. Design/methodology/approach: The…

PAiD: Pennsylvania Association for Individuals "with" Disabilities

ERIC Educational Resources Information Center

Szelong, Brenda

2006-01-01

Carmen Scialabba was on his way to making a name for himself in professional boxing, winning the 1959 All Marine Corps Lightweight Boxing Championship and realizing his dream of boxing at Madison Square Garden when his dreams were shattered after contracting polio at the age 25. But his disability did not stop him from earning a degree and…

Leading the Way: 25 Women Making a Difference

ERIC Educational Resources Information Center

Diverse: Issues in Higher Education, 2012

2012-01-01

When it comes to leadership, women are now taking on long overdue roles. This article presents 25 dynamic women in the world of higher education and beyond. They lead some of the most demanding and consequential organizations and programs on the planet. No longer sitting on the decision-making sidelines, they have shattered the glass ceiling and,…

Shattered Vision: Disenchantment of Couplehood among Female Survivors of Violence in the Shadow of Their Family-of-Origin Experiences

ERIC Educational Resources Information Center

Buchbinder, Eli; Goldblatt, Hadass

2011-01-01

This article describes and analyzes the relationship disenchantment of couplehood among female survivors of violence and their family-of-origin experiences of abuse. Twenty Israeli women who were survivors of violence participated in this qualitative research. Each woman underwent three in-depth interviews, two for data collection and one for…

Intelligence Strategy: New Challenges and Opportunities. NDIC-ODNI Conference Proceedings 26-27 September 2007

DTIC Science & Technology

2008-10-01

leadership positions in Al Qaeda are egyptian , not Saudi. The magic was Osama bin Laden was willing to die for his cause, and he was forceful, loves...way through half a dozen Kleenexes.” He then describes a visit he made to Hussein’s tomb at Karbala. “Sud- denly the peace was shattered by moans and

Recession Amnesia and the Prospects for New England's Institutions

ERIC Educational Resources Information Center

Halfond, Jay A.

2010-01-01

Among the little truly predictable, the author suggests three truths. First is the inevitability of recessions. Second is the belief that, in prosperity, these good times will just keep on rolling. Third is the fall. Bubbles will burst, myths shatter, plans unravel and pain sadly borne unjustly by those who didn't have a hand in the decisions that…

Working beyond the Glass Ceiling: Women Managers in Initial Teacher Training in England

ERIC Educational Resources Information Center

Thompson, Barbara

2007-01-01

Recently in England, women have been successful in obtaining managerial responsibilities in the field of teacher training. In this setting at least, it could be argued that the glass ceiling that has kept women in lower-paid and lower status posts has been shattered. In order to explore this proposition from the perspective of those who work as…

Deadly Serious: The Boston Marathon Tragedy and Education

ERIC Educational Resources Information Center

Harney, John O.

2013-01-01

Two bombs exploded at the Boston Marathon on Monday, April 15, killing three and injuring more than 260. The pressure-cooker bombs sent shrapnel at leg-level, leading to amputations for 15 victims. An immediate concern was how to deal with the feelings of school children whose sense of safety was shattered by the blasts. As the city healed, Boston…

"Grief that Has No Vent in Tears, Makes Other Organs Weep." Seeking Refuge from Trauma in the Medical Setting

ERIC Educational Resources Information Center

Martin, Paddy

2012-01-01

This paper will look at work carried out with asylum-seeking families and children within a hospital paediatric setting, exploring theories that can help us to understand how highly traumatic experiences, emotionally and cognitively unprocessed, may become expressed bodily. The case examples will show how these shattered and dislocated patients…

Shattered Dreams of Professional Competence: The Impact of Client Suicides on Mental Health Practitioners and How to Prepare for It

ERIC Educational Resources Information Center

Juhnke, Gerald A.; Granello, Paul F.

2005-01-01

This article reviews the frequency of suicide, compares and contrasts suicide prediction to suicide assessment and provides a succinct overview of suicide high risk factors that mental health practitioners should be aware. Finally, the article describes common symptoms experienced by mental health practitioners who survive their clients' suicides,…

Implications of Geology for Construction

NASA Technical Reports Server (NTRS)

Rickman, Doug

2009-01-01

The surface of the Moon is covered in regolith, which is NOT soil! The regolith is shattered igneous rock plus glass. The particles are unsorted, unweathered and not abraided. Modeling of the regolith at the level of individual particles will be very problematic. Modeling of the regolith, if successful for one area, will be successful for most other areas if variation in particle size is addressed.

Using Corporate Tools for Organizational Development to Affect Cultural and Structural Change in the Academy: Gallup Impact Planning at the University of Nebraska-Lincoln

ERIC Educational Resources Information Center

Latta, Gail F.

2006-01-01

External pressures have transformed academic life, shattering the roles and relationships that created a sense of community. Increasingly the challenges of fostering an engaged workforce in these institutions mirror the corporate world. Leaders at UNL have adapted Gallup's organizational development strategy to improve faculty engagement and…

Status and use of important native grasses adapted to sagebrush communities

Treesearch

Thomas A. Jones; Steven R. Larson

2005-01-01

Due to the emphasis on restoration, native cool-season grass species are increasing in importance in the commercial seed trade in the Western U.S. Cultivated seed production of these native grasses has often been hampered by seed dormancy, seed shattering, and pernicious awns that are advantageous outside of cultivation. Relatively low seed yields and poor seedling...

Are we on the right track: Can our understanding of abscission in model systems promote or derail making improvements in less studied crops

USDA-ARS?s Scientific Manuscript database

As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abs...

Identification of QTL controlling domestication-related traits in cowpea (Vigna unguiculata L. Walp).

PubMed

Lo, Sassoum; Muñoz-Amatriaín, María; Boukar, Ousmane; Herniter, Ira; Cisse, Ndiaga; Guo, Yi-Ning; Roberts, Philip A; Xu, Shizhong; Fatokun, Christian; Close, Timothy J

2018-04-19

Cowpea (Vigna unguiculata L. Walp) is a warm-season legume with a genetically diverse gene-pool composed of wild and cultivated forms. Cowpea domestication involved considerable phenotypic changes from the wild progenitor, including reduction of pod shattering, increased organ size, and changes in flowering time. Little is known about the genetic basis underlying these changes. In this study, 215 recombinant inbred lines derived from a cross between a cultivated and a wild cowpea accession were used to evaluate nine domestication-related traits (pod shattering, peduncle length, flower color, days to flowering, 100-seed weight, pod length, leaf length, leaf width and seed number per pod). A high-density genetic map containing 17,739 single nucleotide polymorphisms was constructed and used to identify 16 quantitative trait loci (QTL) for these nine traits. Based on annotations of the cowpea reference genome, genes within these regions are reported. Four regions with clusters of QTL were identified, including one on chromosome 8 related to increased organ size. This study provides new knowledge of the genomic regions controlling domestication-related traits in cowpea as well as candidate genes underlying those QTL. This information can help to exploit wild relatives in cowpea breeding programs.

Global Conflicts Shattered World Peace: John Dewey's Influence on Peace Educators and Practitioners

ERIC Educational Resources Information Center

Cohan, Audrey; Howlett, Charles F.

2017-01-01

The need to build an awareness of peace and of peace education is often a message that is difficult to share with the larger society. John Dewey, an acclaimed American philosopher and intellectual, used his public platform to espouse his ideas on democracy and peace as a resolution to global discord during the years preceding and during World Wars…

Population structure and genetic diversity in North American Hedysarum boreale Nutt.

Treesearch

Bradley S. Bushman; Steven R. Larson; Michael D. Peel; Michael E. Pfrender

2007-01-01

Hedysarum boreale Nutt. is a perennial legume native to western North America, with robust foliage in the late spring season. Due to its wide native range, forage value, and N2 fixation, H. boreale is of interest for rangeland revegetation and production. Seed cost is a major obstacle for utilization of H. boreale, primarily due to seed shattering and unreliable seed...

78 FR 19303 - Notice of Inventory Completion for Native American Human Remains and Associated Funerary Objects...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... are 22 shell beads, 24 pieces of a single Baytown Plain ceramic jar, and 13 ceramic sherds. The Boyd site is located in Madison County, MS, and consists of a village area and six mounds. On the basis of... faunal elements, 2 flakes, 1 piece of shatter, 4 points, 1 flake tool, 1 piece of charcoal, 1 discoidal...

Shattering the Glass Ceiling. Issues and Solutions in Promoting the Advancement of Women and Minorities to Executive Management in Corporate America. White Paper 1966.

ERIC Educational Resources Information Center

Microquest Corp., San Rafael, CA.

Despite their progress in the workplace in recent years, women and minorities still remain greatly underrepresented in executive roles in major U.S. companies. The barriers, attitudes, and practices that deter the advancement of women and minorities into executive ranks collectively result in the phenomenon known as the "Glass Ceiling."…

Disaster Preparedness in the American Academy: A Study of Institutional Context Factors for Compliance with the National Incident Management System

ERIC Educational Resources Information Center

Wilder, Paul Joseph

2012-01-01

Recent major disaster events at colleges and universities around the nation have demonstrated that change is needed in the way that higher education institutions (HEIs) approach disaster preparation. The comforting notion that HEIs are immune to natural and manmade hazards has been shattered by events such as the Virginia Tech massacre and…

"Listen and I Tell You Something": Storytelling and Social Action in the Healing of the Oppressed

ERIC Educational Resources Information Center

Leseho, Johanna; Block, Laurie

2005-01-01

The process of healing from life under a military dictatorship is slow and arduous. Reviving one's sense of self when the peace has been shattered; articulating vision and purpose in a culture and a community polarized and divided, requires both a connection to the spiritual and an outlet for direct action. In both cases it is necessary to reclaim…

Educator's Guide to Two Towns of Jasper

ERIC Educational Resources Information Center

Dow, Whitney; Williams, Marco

2004-01-01

In June 1998, news of a horrific murder outraged the nation and the world. Three white men chained James Byrd, Jr., a black man, to the back of a truck and dragged him to his death just outside Jasper, Texas. The crime took place at a time when many people believed that "America was moving beyond race." The crime shattered that notion. Or did it?…

Southern pulpwood production, 1968

Treesearch

Roy C. Beltz

1969-01-01

Southern forests yielded 37,075,355 cords of pulpwood in 1968, shattering the 1967 record by 10 percent (fig. 1 ) . Roundwood production, which declined slightly in 1967, rose 9 percent in 1968 to 29,500,697 cords. The use of plant residues for pulp climbed 17 percent to a record 7,574,658 cord-equivalents. About 75 percent of the 3.4 million cord increase was in pine-...

A Numeric Scorecard Assessing the Mental Health Preparedness for Large-Scale Crises at College and University Campuses: A Delphi Study

ERIC Educational Resources Information Center

Burgin, Rick A.

2012-01-01

Large-scale crises continue to surprise, overwhelm, and shatter college and university campuses. While the devastation to physical plants and persons is often evident and is addressed with crisis management plans, the number of emotional casualties left in the wake of these large-scale crises may not be apparent and are often not addressed with…

Picture Books: Can They Help Caregivers Create an "Illusion of Safety" for Children in Unsafe Times?

ERIC Educational Resources Information Center

McNamee, Abigail; Mercurio, Mia Lynn

2006-01-01

The authors believe that children need to feel safe--they need the illusion of safety--so that they can develop in a healthy way. But it is an "illusion" because in reality safety is never guaranteed for anyone. At times, traumatic events disrupt the safe environments that people have created. Janoff-Buhlman (1992) describes the "shattering of…

Lunar anorthosite 15415: Texture, mineralogy, and metamorphic history

USGS Publications Warehouse

James, O.B.

1972-01-01

Lunar anorthosite 15415 consists almost entirely of anorthite (homogeneous anorthite 96.6 molecule percent), with accessory diopsidic augite and traces of hypersthene, ilmenite, and a silica mineral. The rock has had a complex metamorphic history. The texture reflects at least two episodes of shearing (followed by intense and partial recrystallization, respectively), one episode of cataclastic deformation, and one or more episodes of shattering and fragmentation.

Recent improvements in hydrometeor sampling using airborne holography

NASA Astrophysics Data System (ADS)

Stith, J. L.; Bansemer, A.; Glienke, S.; Shaw, R. A.; Aquino, J.; Fugal, J. P.

2017-12-01

Airborne digital holography provides a new technique to study the sizes, shapes and locations of hydrometeors. Airborne holographic cameras are able to capture more optical information than traditional airborne hydrometeor instruments, which allows for more detailed information, such as the location and shape of individual hydrometeors over a relatively wide range of sizes. These cameras can be housed in an anti-shattering probe arm configuration, which minimizes the effects of probe tip shattering. Holographic imagery, with its three dimensional view of hydrometeor spacing, is also well suited to detecting shattering events when present. A major problem with digital holographic techniques has been the amount of machine time and human analysis involved in analyzing holographic data. Here, we present some recent examples showing how holographic analysis can improve our measurements of liquid and ice particles and we describe a format we have developed for routine archiving of Holographic data, so that processed results can be utilized more routinely by a wider group of investigators. We present a side-by-side comparison of the imagery obtained from holographic reconstruction of ice particles from a holographic camera (HOLODEC) with imagery from a 3VCPI instrument, which utilizes a tube-based sampling geometry. Both instruments were carried on the NSF/NCAR GV aircraft. In a second application of holographic imaging, we compare measurements of cloud droplets from a Cloud Droplet Probe (CDP) with simultaneous measurements from HOLODEC. In some cloud regions the CDP data exhibits a bimodal size distribution, while the more local data from HOLODEC suggests that two mono-modal size distributions are present in the cloud and that the bimodality observed in the CDP is due to the averaging length. Thus, the holographic techniques have the potential to improve our understanding of the warm rain process in future airborne field campaigns. The development of this instrument has been a university and national lab collaboration. Progress in automating the processing techniques has now reached a stage where processed data can be made readily available, so that holographic data from a field campaign can be utilized by a wider group of investigators.

Apparent Brecciation Gradient, Mount Desert Island, Maine

NASA Astrophysics Data System (ADS)

Hawkins, A. T.; Johnson, S. E.

2004-05-01

Mount Desert Island, Maine, comprises a shallow level, Siluro-Devonian igneous complex surrounded by a distinctive breccia zone ("shatter zone" of Gilman and Chapman, 1988). The zone is very well exposed on the southern and eastern shores of the island and provides a unique opportunity to examine subvolcanic processes. The breccia of the Shatter Zone shows wide variation in percent matrix and clast, and may represent a spatial and temporal gradient in breccia formation due to a single eruptive or other catastrophic volcanic event. The shatter zone was divided into five developmental stages based on the extent of brecciation: Bar Harbor Formation, Sols Cliffs breccia, Seeley Road breccia, Dubois breccia, and Great Head breccia. A digital camera was employed to capture scale images of representative outcrops using a 0.5 m square Plexiglas frame. Individual images were joined in Adobe Photoshop to create a composite image of each outcrop. The composite photo was then exported to Adobe Illustrator, which was used to outline the clasts and produce a digital map of the outcrop for analysis. The fractal dimension (Fd) of each clast was calculated using NIH Image and a Euclidean distance mapping method described by Bérubé and Jébrak (1999) to quantify the morphology of the fragments, or the complexity of the outline. The more complex the fragment outline, the higher the fractal dimension, indicating that the fragment is less "mature" or has had less exposure to erosional processes, such as the injection of an igneous matrix. Sols Cliffs breccia has an average Fd of 1.125, whereas Great Head breccia has an average Fd of 1.040, with the stages between having intermediate values. The more complex clasts of the Sols Cliffs breccia with a small amount (26.38%) of matrix material suggests that it is the first stage in a sequence of brecciation ending at the more mature, matrix-supported (71.37%) breccia of Great Head. The results of this study will be used to guide isotopic and geochemical analysis of the matrix igneous material in the attempt to better understand the dynamic processes that occur in subvolcanic environments and the mechanisms involved in breccia formation.

Modeling of Women's 100-M Dash World Record: Wind-Aided or Not?

ERIC Educational Resources Information Center

Hazelrigg, Conner; Waibel, Bryson; Baker, Blane

2015-01-01

On July 16, 1988, Florence Griffith Joyner (FGJ) shattered the women's 100-m dash world record (WR) with a time of 10.49 s, breaking the previous mark by an astonishing 0.27 s. By all accounts FGJ dominated the race that day, securing her place as the premiere female sprinter of that era, and possibly all time. In the aftermath of such an…

Critical Analysis of a Social and Scientific Moral Dilemma: Fifth Graders and Veterans Respond to "Hiroshima No Pika."

ERIC Educational Resources Information Center

Storey, Dee

This document presents results of a survey studying the Japanese picture book, "Hiroshima No Pika." The story aptly captures how a family of three find their lives shattered in a matter of seconds when the atomic bomb is dropped on Hiroshima (Japan) in World War II. Issues presented in the story are: (1) immediate survival in the face of…

Narratives of continuity among older people with late stage chronic kidney disease who decline dialysis.

PubMed

Llewellyn, Henry; Low, Joe; Smith, Glenn; Hopkins, Katherine; Burns, Aine; Jones, Louise

2014-08-01

Chronic and life-threatening conditions are widely thought to shatter the lives of those affected. In this article, we examine the accounts of 19 older people diagnosed with late stage chronic kidney disease who declined dialysis. Accounts were collected through in-depth interview in the United Kingdom (March-November, 2010). Drawing on a phenomenological approach, we focus particularly on the embodied and lived experience of the condition and on how participants constructed treatment modalities and approached treatment choice. We look toward contemporary elaborations of the conceptual framework of biographical disruption to illustrate how participants managed to contain the intrusion of illness and maintain continuity in their lives. We argue that three interactive phenomena mitigated the potential for disruption and allowed participants to maintain continuity: (a) the framing of illness as "old age"; (b) the prior experience of serious illness; and (c) the choice of the treatment with the least potential for disruption. We conclude that a diagnosis of chronic illness in late life does not inevitably shatter lives or engender biographical disruption. Instead, people are able to construct continuity owing to complex narrative interpretations of diagnosis, sensation and treatment choices. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Analyses Reveal Record-Shattering Global Warm Temperatures in 2015

NASA Image and Video Library

2016-01-20

2015 was the warmest year since modern record-keeping began in 1880, according to a new analysis by NASA’s Goddard Institute for Space Studies. The record-breaking year continues a long-term warming trend — 15 of the 16 warmest years on record have now occurred since 2001. Credits: Scientific Visualization Studio/Goddard Space Flight Center Details: Earth’s 2015 surface temperatures were the warmest since modern record keeping began in 1880, according to independent analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA). Globally-averaged temperatures in 2015 shattered the previous mark set in 2014 by 0.23 degrees Fahrenheit (0.13 Celsius). Only once before, in 1998, has the new record been greater than the old record by this much. The 2015 temperatures continue a long-term warming trend, according to analyses by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York (GISTEMP). NOAA scientists agreed with the finding that 2015 was the warmest year on record based on separate, independent analyses of the data. Because weather station locations and measurements change over time, there is some uncertainty in the individual values in the GISTEMP index. Taking this into account, NASA analysis estimates 2015 was the warmest year with 94 percent certainty.

Structure of a seismogenic fault zone in dolostones: the Foiana Line (Italian Southern Alps)

NASA Astrophysics Data System (ADS)

Di Toro, G.; Fondriest, M.; Smith, S. A.; Aretusini, S.

2012-12-01

Fault zones in carbonate rocks (limestones and dolostones) represent significant upper crustal seismogenic sources in several areas worldwide (e.g. L'Aquila 2009 Mw = 6.3 in central Italy). Here we describe an exhumed example of a regionally-significant fault zone cutting dolostones. The Foiana Line (FL) is a major NNE-SSW-trending sinistral transpressive fault cutting sedimentary Triassic dolostones in the Italian Southern Alps. The FL has a cumulative vertical throw of 1.5-2 km that reduces toward its southern termination. The fault zone is 50-300 m wide and is exposed for ~ 10 km along strike within several outcrops exhumed from increasing depths from the south (1 km) to the north (2.5 km). The southern portion of the FL consists of heavily fractured (shattered) dolostones, with particles of a few millimeters in size (exposed in badlands topography over an area of 6 km2), cut by a dense network of 1-20 m long mirror-like fault surfaces with dispersed attitudes. The mirror-like faults have mainly dip-slip reverse kinematics and displacements ranging between 0.04 m and 0.5 m. The northern portion of the FL consists of sub-parallel fault strands spaced 2-5 m apart, surrounded by 2-3 m thick bands of shattered dolostones. The fault strands are characterized by smooth to mirror-like sub-vertical slip surfaces with dominant strike-slip kinematics. Overall, deformation is more localized moving from South to North along the FL. Mirror-like fault surfaces similar to those found in the FL were produced in friction experiments at the deformation conditions expected during seismic slip along the FL (Fondriest et al., this meeting). Scanning Electron Microscope investigations of the natural shattered dolostones beneath the mirror-like fault surfaces show: 1) lack of significant shear strain (even at a few micrometers from the slip surface), 2) pervasive extensional fracturing down to the micrometer scale, 3) exploded clasts with radial fractures, and 4) chains of split clasts (resulting from force chains) oriented at 60-80 degrees to the slip surfaces. Similar features have been reported in natural and experimental pulverized rocks, the latter produced under dynamic stress wave loading conditions. 3-Dimensional rupture simulations along strike-slip faults predict (1) off-fault damage distributions with "flower-like" shapes (broad damage zone near the surface that rapidly narrows with increasing confining pressure, e.g., Ma and Andrews, 2010) and (2) formation of secondary faults/fractures with disperse attitudes and kinematics near the surface, with horizontal slip at depth. Qualitatively, these theoretical results compare favorably with increasing strain localization and a switch in fault kinematics recognized along the FL moving from the southern, shallower portion of the fault zone to the northern, deeper portion. Observations along the FL suggest that the association of shattered dolostones and mirror-like slip surfaces might be a potential indicator of seismic rupture propagation. Further detailed structural mapping along the FL coupled with experimental work on rock pulverization will be necessary to understand rupture dynamics in dolostones.

Archaeological Mitigation of AR-102.

DTIC Science & Technology

1978-07-16

obsidian is especially noticeable. Roxey and Tully noted three discrete lithic areas on this slope adjacent to the fence (see map). The first area was...Polvadera Peak obsidian . These I I I 1 I I II Ii -6- [I points were probably lost during hunts on the slope. Several bifacial knives with heavy...of Polvadera Peak obsidian , the only concentration of this material observed in the survey area. There are small flakes, shatter and similar debitage

Swarm of Comets Artist Concept

NASA Image and Video Library

2015-11-24

This illustration shows a star behind a shattered comet. Observations of the star KIC 8462852 by NASA's Kepler and Spitzer space telescopes suggest that its unusual light signals are likely from dusty comet fragments, which blocked the light of the star as they passed in front of it in 2011 and 2013. The comets are thought to be traveling around the star in a very long, eccentric orbit. http://photojournal.jpl.nasa.gov/catalog/PIA20053

Geographic Concentration of Oil Infrastructure: Issues and Options

DTIC Science & Technology

2007-03-24

their homes and plants , and destroy ports and refineries , thereby shattering the U.S. economy. The scope, scale, frequency and location of terrorist...for the above reasons. The corridor along the Mississippi River between Baton Rouge and New Orleans is home to six major refineries . These... refineries process more than 1.7 million barrels of oil per day to produce 775 thousand barrels of motor gasoline and 440 million barrels of distillate fuel

Little Joe Launch

NASA Image and Video Library

1959-10-04

Launching of the LJ6 Little Joe on Oct. 4, 1959 took place at Wallops Island, Va. This was the first attempt to launch an instrumented capsule with a Little Joe booster. Only the LJ1A and the LJ6 used the space metal chevron plates as heat reflector shields, as they kept shattering. Caption title ...and ascending skyward on a plume of exhaust. Photograph published in Winds of Change, 75th Anniversary NASA publication, page 77, by James Schultz

Some Correlations between Plate Shatter and Fracture Toughness.

DTIC Science & Technology

1987-02-01

temperatures. In this manner, any test for plate cracking should be akin to a Charpy test, where a series of notched test bars are broken over a...cracking under ballistic impact. The PSTT test is analogous to the transition temperature in a Charpy impact test, or to the nil ductility transition (NDT...210 C to -730 C. Standard Charpy specimens were machined from the plates and subsequently precracked in fatigue to about 2.5 mm and dynamically tested

Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California.

PubMed

Kanapeckas, Kimberly L; Tseng, Te-Ming; Vigueira, Cynthia C; Ortiz, Aida; Bridges, William C; Burgos, Nilda R; Fischer, Albert J; Lawton-Rauh, Amy

2018-06-01

Weed evolution from crops involves changes in key traits, but it is unclear how genetic and phenotypic variation contribute to weed diversification and productivity. Weedy rice is a conspecific weed of rice (Oryza sativa) worldwide. We used principal component analysis and hierarchical clustering to understand how morphologically and evolutionarily distinct US weedy rice populations persist in rice fields in different locations under contrasting management regimes. Further, we used a representative subset of 15 sequence-tagged site fragments of expressed genes from global Oryza to assess genome-wide sequence variation among populations. Crop hull color and crop-overlapping maturity dates plus awns, seed (panicle) shattering (> 50%), pigmented pericarp and stature variation (30.2% of total phenotypic variance) characterize genetically less diverse California weedy rice. By contrast, wild-like hull color, seed shattering (> 50%) and stature differences (55.8% of total phenotypic variance) typify genetically diverse weedy rice ecotypes in Arkansas. Recent de-domestication of weedy species - such as in California weedy rice - can involve trait combinations indistinguishable from the crop. This underscores the need for strict seed certification with genetic monitoring and proactive field inspection to prevent proliferation of weedy plant types. In established populations, tillage practice may affect weed diversity and persistence over time. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Simulating galactic dust grain evolution on a moving mesh

NASA Astrophysics Data System (ADS)

McKinnon, Ryan; Vogelsberger, Mark; Torrey, Paul; Marinacci, Federico; Kannan, Rahul

2018-05-01

Interstellar dust is an important component of the galactic ecosystem, playing a key role in multiple galaxy formation processes. We present a novel numerical framework for the dynamics and size evolution of dust grains implemented in the moving-mesh hydrodynamics code AREPO suited for cosmological galaxy formation simulations. We employ a particle-based method for dust subject to dynamical forces including drag and gravity. The drag force is implemented using a second-order semi-implicit integrator and validated using several dust-hydrodynamical test problems. Each dust particle has a grain size distribution, describing the local abundance of grains of different sizes. The grain size distribution is discretised with a second-order piecewise linear method and evolves in time according to various dust physical processes, including accretion, sputtering, shattering, and coagulation. We present a novel scheme for stochastically forming dust during stellar evolution and new methods for sub-cycling of dust physics time-steps. Using this model, we simulate an isolated disc galaxy to study the impact of dust physical processes that shape the interstellar grain size distribution. We demonstrate, for example, how dust shattering shifts the grain size distribution to smaller sizes resulting in a significant rise of radiation extinction from optical to near-ultraviolet wavelengths. Our framework for simulating dust and gas mixtures can readily be extended to account for other dynamical processes relevant in galaxy formation, like magnetohydrodynamics, radiation pressure, and thermo-chemical processes.

Initiation of secondary ice production in clouds

NASA Astrophysics Data System (ADS)

Sullivan, Sylvia C.; Hoose, Corinna; Kiselev, Alexei; Leisner, Thomas; Nenes, Athanasios

2018-02-01

Disparities between the measured concentrations of ice-nucleating particles (INPs) and in-cloud ice crystal number concentrations (ICNCs) have led to the hypothesis that mechanisms other than primary nucleation form ice in the atmosphere. Here, we model three of these secondary production mechanisms - rime splintering, frozen droplet shattering, and ice-ice collisional breakup - with a six-hydrometeor-class parcel model. We perform three sets of simulations to understand temporal evolution of ice hydrometeor number (Nice), thermodynamic limitations, and the impact of parametric uncertainty when secondary production is active. Output is assessed in terms of the number of primarily nucleated ice crystals that must exist before secondary production initiates (NINP(lim)) as well as the ICNC enhancement from secondary production and the timing of a 100-fold enhancement. Nice evolution can be understood in terms of collision-based nonlinearity and the phasedness of the process, i.e., whether it involves ice hydrometeors, liquid ones, or both. Ice-ice collisional breakup is the only process for which a meaningful NINP(lim) exists (0.002 up to 0.15 L-1). For droplet shattering and rime splintering, a warm enough cloud base temperature and modest updraft are the more important criteria for initiation. The low values of NINP(lim) here suggest that, under appropriate thermodynamic conditions for secondary ice production, perturbations in cloud concentration nuclei concentrations are more influential in mixed-phase partitioning than those in INP concentrations.

The Oakland Conglomerate: a Hayward Fault Teconite?

NASA Astrophysics Data System (ADS)

Strayer, L. M.; Allen, J. R.

2008-12-01

The Late Cretaceous Oakland Conglomerate (OC), a coarse-grained cobble and sandstone unit of the Great Valley Sequence is a tectonite. Faulted and shattered cobbles and well developed grain-on-grain contact features between clasts are ubiquitous and penetrative throughout conglomeratic lenses. The OC outcrops east of the Hayward fault (HF) and adjacent to the Chabot fault in the East Bay Hills. It overlies the Knoxville Formation and may have been buried beneath 4-6 km of younger units. The OC is a proximal submarine fan deposit with sediment sourced to the ancestral Klamath and Sierra Nevada. Clast types are dominated by volcanics, granitoids, as well as numerous quartzites, perhaps reflecting complex provenance:Klamath and pre-Sierran arc and pre-Cretaceous Basin and Range. And although there was a significant interval between the Late-K deposition of the OC and the inception of San Andreas faulting in the Bay Area, its 1-2 km proximity to the HF in the Oakland Metropolitan area strongly suggests that much of the brittle-plastic deformation within the OC may be due to earthquakes upon the nearby Hayward fault. Clasts with the OC are frequently shattered, fractured or faulted. Most have grain-on-grain contact features on their surfaces regardless of whether they are matrix or grain supported. Faulting in the cobbles ranges from outcrop scale, penetrative and often conjugate shear fracture sets that run through both cobbles and matrix (if present), to closely spaced en-echelon faults that clearly deform cobbles, and radially shattered specimens with nearly conical conjugate shear fractures that are clearly the result of point loading due to grain-on-grain contact. There are at least 3 types of contact structures, ranging from: 1) Type-H, bright circular halos with little or no surface dimpling, likely the result of intense microfracture at the contact; 2) Type-S, shattered, rounded 'firing-pin' structures that have pulverized, depressed contact that is the locus of radial and conjugate shear fractures that offset the surface of the clasts. Cross-cutting relationships suggest that pulverized dimpling and faulting are synchronous. These appear to form both with and without matrix involvement. 3) Type-P, clean, well formed, pressure solution pits, often rimmed by a discrete lip of adjacent matrix, likely cemented by locally available quartz. These are often cut by the faults of Type-S above. Type-S and Type-P contact features can and often do occur in the same specimen. Type-H and some Type-S contacts appear to be products of 'clean' grain-on-grain contact without matrix involvement. Differences between the bright halo and the pressure solution pits may be due to the presence of a thin layer of matrix sand, which appears to facilitate wholesale pressure solution. Faults within the matrix and cobbles are often conjugate, and penetrative at the outcrop scale. Initial structural analysis suggests these faults might lend themselves to stress inversion techniques if enough examples are available. Since many of the cobbles were re-cemented after they were faulted, there may be potential to gain insight into their burial depths during these events by investigating their geochemistry. The OC, given its very close proximity to the HF, may provide a record of the shortening direction and stress orientations directly adjacent to this important plate boundary.

Mars, then and now

NASA Astrophysics Data System (ADS)

Horowitz, N. H.

1987-12-01

The shattering of the Lowellian picture of Mars by the Mount Wilson observation and Mariners 4, 6, and 7 is discussed. The Viking mission, instrumented to continue the search for life on Mars, did not detect even a trace of organic matter at the ppb-level of detectability. However, the experiments did indicate the presence of OH radicals (or peroxides derived from them) in the Martian soil. On Mars, OH would diffuse into the dry soil and there act as a strong oxidizing agent.

Key players must help shatter the glass ceiling, say experts.

PubMed

Eubanks, P

1991-10-05

Women are continuing to move up through the management pipeline in hospitals across the country; but is top management prepared? Although many women are aiming for the highest levels in management, a recent survey of female and male health care executives indicates that critical changes must be made by top management and boards of hospitals before those women can continue to advance accordingly. Meanwhile, women's experience as senior executives has been quite different from men's, the survey also shows.

Shock Absorbing System

NASA Technical Reports Server (NTRS)

1982-01-01

A lightweight, inexpensive shock-absorbing system, developed by Langley Research Center 20 years ago, is now in service as safety device for an automated railway at Duke University Medical Center. The transportation system travels at about 25 miles per hour, carrying patients, visitors, staff and cargo. At the end of each guideway of the system are "frangible," (breakable) tube "buffers." If a slowing car fails to make a complete stop at the terminal, it would bump and shatter the tubes, absorbing energy that might otherwise jolt the passengers or damage the vehicle.

Nurturer, Victim, Seductress: Gendered Roles in Terrorism

DTIC Science & Technology

2018-04-20

suicide bombing , as a mark of bravery and a way into paradise. Martyrdom as a tactic was a component of AQ culture to return to the glory days of...wrote that the bombing was monumental in shattering a glass ceiling and it “elevated the value of Arab women and, in one moment, and with enviable...courage, put an end to the unending debate about equality between men and women.”23 Conversely, Stephanie Shemin condemned the bombing in the Chicago

The Coast Artillery Journal. Volume 83, Number 3, May-June 1940

DTIC Science & Technology

1940-06-01

remembers But the badly shattered rankswere incapable of immediate his troops and issues a Special Order: "The Major Gen - consolidation, so the...popular fanc )’ was a boule- vardier who wore a waxy black mus- tache and a pointed black beard; he was an effeminate, vain, and to Eng- lish and American...D. C. Lieutcnant Colonel \\V. C. Footc, to Gen - eral Staff Corps, 6th Corps Arca. l.ieutenant Colonel Ferdinand F. Gallag- her, to instructor

A Numerical Study of Projectile Impact on Explosives

DTIC Science & Technology

1977-04-01

Whitbreac5 and Dewey and Slade6 performed and analyzed this type of test for charges which were unconfined or confined only on the impacted surface...With such charges one observes either that the charge detorxates or is shattered and the result is recorded as no reaction. Dewey and Slade, and Brown...detonations. At the onset of this work, we expectrd that plastic 5. S. Brown and E. Whitbread, Les Ondes de Detonation, 1961. 6. J. Dewey and D. Slade

Enemies into Allies: American Stability Operations and the Transformation of Japan 1945-1952

DTIC Science & Technology

2011-05-19

on Japanese forces in Manchuria finally shattered the last hopes of Emperor Hirohito and Japan’s governmental leadership.7 Jun Eto suggested that...of Modern Japan (New York: HarperCollins Publishers, 2000), 511. 8 Jun Eto , A Nation Reborn – A Short History of Postwar Japan (Tokyo: International...Modern Japan, trans. Mikiso Hane and John K . Urda (New York: Free Press, 1995), 39. First- 17 Brian J. McVeigh, Nationalisms of Japan – Managing and

An Index of Horror: To Catalog an Extensive Video Archive of Holocaust Testimony, the U. of Southern California Turned to the Human Touch and a System that Could be Used for Other Large Archives

ERIC Educational Resources Information Center

Carlson, Scott

2007-01-01

On video, a woman describes how her life was shattered. She speaks about her family splitting up, about her loved ones being killed, about one of the most systematic genocides in history. Indexers at the University of Southern California's Shoah Foundation Institute for Visual History and Education have watched 120,000 hours of these testimonies…

Pavement Maintenance Management for Roads and Parking Lots.

DTIC Science & Technology

1981-10-01

PAVEMENT INSPECTION SHEET aRANCH SECT ION DA TE SAMPLE UNIT SURVEYED BY SLAB SIZE * 0 0 0 Distress Types !0 2f Blow- Up 3’ Polished Buckling/Shattering...10 21 Blow- up 31 Poisnec Buckling/Shatternrg Aggregate 0 1 22. Corner Break 32 Porouis 23. D’viOea SIcD 33 Ptmo,nq 9 24 Durability . " 34 Pancnout...Load Durability Drainage Other Factors Corner Break Blow- up Corner Break Faulting Divided Slab Ŕ" Cracking Divided Slab Lane/Shoulder Dropoff

Comment on 'Entropy lowering in ion-atom collisions'

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

Ostrovsky, V. N.

2006-01-15

The recent experimental result by Nguyen et al. [Phys. Rev. A 71, 062714 (2005)] on the ratio of cross sections for charge exchange processes Rb{sup +}+Rb(5s){yields}Rb(5p)+Rb{sup +} and Rb{sup +}+Rb(5p){yields}Rb(5s)+Rb{sup +} is quantitatively derived from simple considerations within the general framework of the quasimolecular theory. Contrary to the expectations, applicability of the Demkov model for charge exchange with small energy defect is not shattered.

CTC Sentinel. Volume 4 Number 1, January 2011

DTIC Science & Technology

2011-01-01

Muslims had been forced to wear the hijab . The ISoc also prevented Muslims from using an “interfaith prayer room,” a practice which they believed was...from terrorism in an al-Jazira broadcast in October 2004. This sense of immunity was shattered twice in December 2010. First, a suicide bomber...bomber before the attack, as he had studied and lived for a decade in the United Kingdom. At the same time, he admitted he had traveled to Iraq to

Proceedings of Seminar on Air Antitank Warfare Held at Springfield, Virginia on 25-26 May 1978

DTIC Science & Technology

1979-05-01

there is strategy . You have to get inside your adversary’s organization—learn his strengths, weaknesses, movement, and intentions. In other words...doing it maybe on a larger scale instead of down at the battalion or platoon levels . Finally, our third basis of attack is army. You should still do...all these things at the army level so that you can literally shatter them and pull them apart. Finally he brings up the notion of attacking cities

Shock metamorphism and impact melting in small impact craters on Earth: Evidence from Kamil crater, Egypt

NASA Astrophysics Data System (ADS)

Fazio, Agnese; Folco, Luigi; D'Orazio, Massimo; Frezzotti, Maria Luce; Cordier, Carole

2014-12-01

Kamil is a 45 m diameter impact crater identified in 2008 in southern Egypt. It was generated by the hypervelocity impact of the Gebel Kamil iron meteorite on a sedimentary target, namely layered sandstones with subhorizontal bedding. We have carried out a petrographic study of samples from the crater wall and ejecta deposits collected during our first geophysical campaign (February 2010) in order to investigate shock effects recorded in these rocks. Ejecta samples reveal a wide range of shock features common in quartz-rich target rocks. They have been divided into two categories, as a function of their abundance at thin section scale: (1) pervasive shock features (the most abundant), including fracturing, planar deformation features, and impact melt lapilli and bombs, and (2) localized shock features (the least abundant) including high-pressure phases and localized impact melting in the form of intergranular melt, melt veins, and melt films in shatter cones. In particular, Kamil crater is the smallest impact crater where shatter cones, coesite, stishovite, diamond, and melt veins have been reported. Based on experimental calibrations reported in the literature, pervasive shock features suggest that the maximum shock pressure was between 30 and 60 GPa. Using the planar impact approximation, we calculate a vertical component of the impact velocity of at least 3.5 km s-1. The wide range of shock features and their freshness make Kamil a natural laboratory for studying impact cratering and shock deformation processes in small impact structures.

Traumatic fracture of a polymethyl methacrylate patient-specific cranioplasty implant.

PubMed

Ko, Andrew L; Nerva, John D; Chang, Jason J J; Chesnut, Randall M

2014-01-01

To present a case of a traumatic fracture of a polymethyl methacrylate (PMMA) patient-specific implant (PSI) for cranioplasty. A 14-year-old boy with a history of right decompressive hemicraniectomy and reconstructive cranioplasty with a PMMA PSI presented after an unhelmeted bicycle accident with somnolence, confusion, seizures, left hemiparesis, and an obviously deformed cranium. Computed tomography scan showed a comminuted, depressed fracture of the implant and cerebral contusions. The implant was seen to be shattered, resulting in displaced, overriding fragments and significant damage to underlying brain. The patient remained neurologically stable. To minimize the number of operations, intervention was delayed while a polyetheretherketone PSI was fabricated. During surgery, it was noted that the fractured pieces of the implant had caused dural lacerations, and some pieces were embedded in brain parenchyma. The fractured PMMA was removed, and the new implant was placed. The patient remained hemiparetic and was later transferred to an inpatient rehabilitation facility. PMMA PSIs are commonly used for large defects and generally have good outcomes with low rates of revision. The case report described involves a shattered PMMA PSI after a traumatic impact, which resulted in hemiparesis. The question arises if this type of complication can be easily avoided with the addition of titanium onlay to restrict displacement in the event of fracture. This onlay represents a minor change of technique that could prevent migration of fracture fragments. Copyright © 2014 Elsevier Inc. All rights reserved.

Sampling hydrometeors in clouds in-situ - the replicator technique

NASA Astrophysics Data System (ADS)

Wex, Heike; Löffler, Mareike; Griesche, Hannes; Bühl, Johannes; Stratmann, Frank; Schmitt, Carl; Dirksen, Ruud; Reichardt, Jens; Wolf, Veronika; Kuhn, Thomas; Prager, Lutz; Seifert, Patric

2017-04-01

For the examination of ice crystals in clouds, concerning their number concentrations, sizes and shapes, often instruments mounted on fast flying aircraft are used. One related disadvantage is possible shattering of the ice crystals on inlets, which has been improved with the introduction of the "Korolev-tip" and by accounting for inter-arrival times (Korolev et al., 2013, 2015), but additionally, the typically fast flying aircraft allow only for a low spatial resolution. Alternative sampling methods have been introduced as e.g., a replicator by Miloshevich & Heymsfield (1997) and an in-situ imager by by Kuhn & Heymsfield (2016). They both sample ice crystals onto an advancing stripe while ascending on a balloon, conserving the ice crystals either in formvar for later off-line analysis under a microscope (Miloshevich & Heymsfield, 1997) or imaging them upon their impaction on silicone oil (Kuhn & Heymsfield, 2016), both yielding vertical profiles for different ice crystal properties. A measurement campaign was performed at the Lindenberg Meteorological Observatory of the German Meteorological Service (DWD) in Germany in October 2016, during which both types of instruments were used during balloon ascents, while ground-based Lidar and cloud-radar measurements were performed simultaneously. The two ice particle sondes were operated by people from the Lulea University of Technology and from TROPOS, where the latter one was made operational only recently. Here, we will show first results of the TROPOS replicator on ice crystals sampled during one ascent, for which the collected ice crystals were analyzed off-line using a microscope. Literature: Korolev, A., E. Emery, and K. Creelman (2013), Modification and tests of particle probe tips to mitigate effects of ice shattering, J. Atmos. Ocean. Tech., 30, 690-708, 2013. Korolev, A., and P. R. Field (2015), Assessment of the performance of the inter-arrival time algorithm to identify ice shattering artifacts in cloud particle probe measurements, Atmos. Meas. Tech., 8(2), 761-777, doi:10.5194/amt-8-761-2015. Kuhn, T., and A. J. Heymsfield (2016), In situ balloon-borne ice particle imaging in high-latitude cirrus, Pure Appl. Geophys., 173(9), 3065-3084, doi:10.1007/s00024-016-1324-x. Miloshevich, L. M., and A. J. Heymsfield (1997), A balloon-borne continuous cloud particle replicator for measuring vertical profiles of cloud microphysical properties: Instrument design, performance, and collection efficiency analysis, J. Atmos. Oceanic Technol., 14(4), 753-768, doi:10.1175/1520-0426(1997)014<0753:abbccp>2.0.co;2.

Decontaminating Solar Wind Samples with the Genesis Ultra-Pure Water Megasonic Wafer Spin Cleaner

NASA Technical Reports Server (NTRS)

Calaway, Michael J.; Rodriquez, M. C.; Allton, J. H.; Stansbery, E. K.

2009-01-01

The Genesis sample return capsule, though broken during the landing impact, contained most of the shattered ultra-pure solar wind collectors comprised of silicon and other semiconductor wafers materials. Post-flight analysis revealed that all wafer fragments were littered with surface particle contamination from spacecraft debris as well as soil from the impact site. This particulate contamination interferes with some analyses of solar wind. In early 2005, the Genesis science team decided to investigate methods for removing the surface particle contamination prior to solar wind analysis.

Analysis of Multiple-Impact Ballistic Performance of a Tempered Glass Laminate with a Strike Face Film

DTIC Science & Technology

2014-02-01

a 0.18 in thick polymer interlayer between two layers of 0.5 in tempered silica based “ soda lime ” glass . A 0.08 in shatter resistant film was...AFCEC-CX-TY-TR-2014-0005 ANALYSIS OF MULTIPLE-IMPACT BALLISTIC PERFORMANCE OF A TEMPERED GLASS LAMINATE WITH A STRIKE FACE FILM Michael A. Magrini...Interim Technical Report 3 JAN 2012 to 2 JAN 2013 Analysis of Multiple-Impact Ballistic Performance of A Tempered Glass Laminate with a Strike Face Film

Lonar Lake, India: An impact Crater in basalt

USGS Publications Warehouse

Fredriksson, K.; Dube, A.; Milton, D.J.; Balasundaram, M.S.

1973-01-01

Discovery of shock-metamorphosed material establishes the impact origin of Lonar Crater. Coarse breccia with shatter coning and microbreccia with moderately shocked fragments containing maskelynite were found in drill holes through the crater floor. Trenches on the rim yield strongly shocked fragments in which plagioclase has melted and vesiculated, and bombs and spherules of homogeneous rock melt. As the only known terrestrial impact crater in basalt, Lonar Crater provides unique opportunities for comparison with lunar craters. In particular, microbreccias and glass spherules from Lonar Crater have close analogs among the Apollo specimens.

Termination of psychoanalysis and September 11.

PubMed

Brenner, Ira

2006-07-01

In the United States, the last illusion of safety from problems in distant parts of the world was shattered on September 11, 2001. Psychoanalysts are in a unique position to both experience and examine how such a man-made social disaster becomes internalized and affects one's psychic reality by studying the effects of that day on patients already engaged in a psychoanalytic process. The author hypothesizes that in one such case, that of Mr. N, the termination phase was significantly affected. Furthermore, Mr. N's reaction to reading the analyst's clinical write-up further influenced the termination phase.

Energy-Efficient Systems Eliminate Icing Danger for UAVs

NASA Technical Reports Server (NTRS)

2010-01-01

Ames Research Center engineer Leonard Haslim invented an anti-icing t echnology called an electroexpulsive separation system, which uses m echanical force to shatter potentially dangerous ice buildup on an ai rcraft surface. Temecula, California-based Ice Management Systems (no w known as IMS-ESS) licensed the technology from Ames and has discov ered a niche market for the lightweight, energy-efficient technology: unmanned aerial vehicles (UAVs). IMS-ESS systems now prevent damagi ng ice accumulation on military UAVs, allowing the vehicles to carry out crucial missions year round.

The Australian Medical Support Force in Rwanda.

PubMed

Ramsey, W; Bridgford, L R; Lusby, R J; Pearn, J H

In the aftermath of the Rwandan civil war, Australia's defence forces deployed a medical force to support the United Nations Assistance Mission. In this article, Wayne Ramsey, Commander of the Australian contingent, Lindsay R Bridgford, Officer Commanding Bravo Section, Robert J Lusby, Lt.-Colonel (Surgeon), Australian Medical Support Force Hospital, and John H Pearn, Colonel, and Director of Intensive Care in the Australian Medical Support Force Hospital, describe the Australian effort in the rebuilding of a shattered people and, in particular, of Kigali Central Hospital, the country's major medical facility.

http://www.nasa.gov/feature/goddard/2016/hubble-team-breaks-cosmic-distance-record

NASA Image and Video Library

2016-03-03

By pushing NASA’s Hubble Space Telescope to its limits, an international team of astronomers has shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe. This surprisingly bright infant galaxy, named GN-z11, is seen as it was 13.4 billion years in the past, just 400 million years after the Big Bang. GN-z11 is located in the direction of the constellation of Ursa Major. Read more: go.nasa.gov/1oSqHad

Methods to Implement Innovation and Entrepreneurship in Physics

NASA Astrophysics Data System (ADS)

Arion, Douglas

2015-03-01

The physics community is beginning to become aware of the benefits of entrepreneurship and innovation education: greater enrollments, improved students satisfaction, a wider range of interesting research problems, and the potential for greater return from more successful alumni. This talk will suggest a variety of mechanisms by which physics departments can include entrepreneurship and innovation content within their programs - without necessarily requiring earth-shattering changes to the curriculum. These approaches will thus make it possible for departments to get involved with entrepreneurship and innovation, and grow those components into vibrant activities for students and faculty.

Cumulative Damage in Strength-Dominated Collisions of Rocky Asteroids: Rubble Piles and Brick Piles

NASA Technical Reports Server (NTRS)

Housen, Kevin

2009-01-01

Laboratory impact experiments were performed to investigate the conditions that produce large-scale damage in rock targets. Aluminum cylinders (6.3 mm diameter) impacted basalt cylinders (69 mm diameter) at speeds ranging from 0.7 to 2.0 km/s. Diagnostics included measurements of the largest fragment mass, velocities of the largest remnant and large fragments ejected from the periphery of the target, and X-ray computed tomography imaging to inspect some of the impacted targets for internal damage. Significant damage to the target occurred when the kinetic energy per unit target mass exceeded roughly 1/4 of the energy required for catastrophic shattering (where the target is reduced to one-half its original mass). Scaling laws based on a rate-dependent strength were developed that provide a basis for extrapolating the results to larger strength-dominated collisions. The threshold specific energy for widespread damage was found to scale with event size in the same manner as that for catastrophic shattering. Therefore, the factor of four difference between the two thresholds observed in the lab also applies to larger collisions. The scaling laws showed that for a sequence of collisions that are similar in that they produce the same ratio of largest fragment mass to original target mass, the fragment velocities decrease with increasing event size. As a result, rocky asteroids a couple hundred meters in diameter should retain their large ejecta fragments in a jumbled rubble-pile state. For somewhat larger bodies, the ejection velocities are sufficiently low that large fragments are essentially retained in place, possibly forming ordered "brick-pile" structures.

Newly identified "Tunnunik" impact structure, Prince Albert Peninsula, northwestern Victoria Island, Arctic Canada

NASA Astrophysics Data System (ADS)

Dewing, Keith; Pratt, Brian R.; Hadlari, Thomas; Brent, Tom; BÉDard, Jean; Rainbird, Robert H.

2013-02-01

Regional geological mapping of the glaciated surface of northwestern Victoria Island in the western Canadian Arctic revealed an anomalous structure in otherwise flat-lying Neoproterozoic and lower Paleozoic carbonate rocks, located south of Richard Collinson Inlet. The feature is roughly circular in plan view, approximately 25 km in diameter, and characterized by quaquaversal dips of approximately 45°, decreasing laterally. The core of the feature also exhibits local vertical dips, low-angle reverse faults, and drag folds. Although brecciation was not observed, shatter cones are pervasive in all lithologies in the central area, including 723 Ma old dikes that penetrate Neoproterozoic limestones. Their abundance decreases distally, and none was observed in surrounding, horizontally bedded strata. This circular structure is interpreted as a deeply eroded meteorite impact crater of the complex type, and the dipping strata as the remnants of the central uplift. The variation in orientation and shape of shatter cones point to variably oriented stresses with the passage of the shock wave, possibly related to the presence of pore water in the target strata as well as rock type and lithological heterogeneities, especially bed thickness. Timing of impact is poorly constrained. The youngest rocks affected are Late Ordovician (approximately 450 Ma) and the impact structure is mantled by undisturbed postglacial sediments. Regional, hydrothermal dolomitization of the Ordovician limestones, possibly in the Late Devonian (approximately 360 Ma), took place before the impact, and widespread WSW-ENE-trending normal faults of probable Early Cretaceous age (approximately 130 Ma) apparently cross-cut the impact structure.

Experiments in DIII-D Toward Achieving Rapid Shutdown with Runaway Electron Suppression

NASA Astrophysics Data System (ADS)

Hollmann, E. M.

2009-11-01

For safe discharge shutdown in future large tokamaks in the event of an unavoidable disruption, it is important to develop rapid (˜ several ms)shutdown methods to avoid large runaway electron currents, which pose a serious threat to plasma facing components. Prevention of runaway current formation has been proposed by either increasing electron-electron collisionality with massive particle injection, or magnetically by using externally applied non-axisymmetric fields to increase radial diffusive losses of a runaway seed population. Experiments studying both approaches have been pursued in the DIII-D tokamak. For collisional suppression, three different rapid shutdown methods are being investigated: massive gas injection, massive shattered cryogenic pellet injection, and polystyrene shell pellet injection. First-of-kind demonstrations of fast shutdowns were produced by 3000 Torr-l (0.8-g) shattered D2 pellets and large, 10-mm diameter, 0.3-g polystyrene shell pellets filled with boron powder. The application of external magnetic perturbations shows promising preliminary results in suppressing seed runaway electrons, although lack of repeatability in the runaway seed term made these results challenging to interpret. Experiments have been performed to help understand how runaways form and are transported during rapid shutdown. These experiments confirm that the commonly used 0D loop voltage + Dreicer evaporation picture of runaway seed formation is not applicable here, with relativistic E > 0.5,MeV electrons forming before any external loop voltage appears. Present applications of 0D, 1D, and 2D models to the rapid shutdown and runaway confinement experiments, as well as preliminary extrapolations to ITER, will be discussed.

Simulations of Collisional Disruption at the Catastrophic Impact Energy Threshold: Effect of the Target's Internal Structure and Diameter

NASA Astrophysics Data System (ADS)

Michel, P.; Benz, W.; Richardson, D. C.

2005-08-01

Recent simulations of asteroid break-ups, including both the fragmentation of the parent body and the gravitational interactions of the fragments, have allowed to reproduced successfully the main properties of asteroid families formed in different regimes of impact energy. Here, using the same kind of simulations, we concentrate on a single regime of impact energy, the so-called catastrophic threshold usually designated by Qcrit, which results in the escape of half of the target's mass. Considering a wide range of diameter values and two kinds of internal structures of the parent body, monolithic and pre-shattered, we analyse their potential influences on the value of Qcrit and on the collisional outcome limited here to the fragment size and ejection speed distributions, which are the main outcome properties used by collisional models to study the evolutions of the different populations of small bodies. For all the considered diameters and the two internal structures of the parent body, we confirm that the process of gravitational reaccumulation is at the origin of the largest remnant's mass. We then find that, for a given diameter of the parent body, the impact energy corresponding to the catastrophic disruption threshold is highly dependent on the internal structure of the parent body. In particular, a pre-shattered parent body containing only damaged zones but no macroscopic voids is easier to disrupt than a monolithic parent body. Other kinds of internal properties that can also characterize small bodies in real populations will be investigated in a future work.

Geology of the Upheaval Dome impact structure, southeast Utah

USGS Publications Warehouse

Kriens, B.J.; Shoemaker, E.M.; Herkenhoff, K. E.

1999-01-01

Two vastly different phenomena, impact and salt diapirism, have been proposed for the origin of Upheaval Dome, a spectacular scenic feature in southeast Utah. Detailed geologic mapping and seismic refraction data indicate that the dome originated by collapse of a transient cavity formed by impact. Evidence is as follows: (1) sedimentary strata in the center of the structure are pervasively imbricated by top-toward-the-center thrust faulting and are complexly folded as well; (2) top-toward-the-center normal faults are found at the perimeter of the structure; (3) clastic dikes are widespread; (4) the top of the underlying salt horizon is at least 500 m below the surface at the center of the dome, and there are no exposures of salt or associated rocks of the Paradox Formation in the dome to support the possibility that a salt diapir has ascended through it; and (5) planar microstructures in quartz grains, fantailed fracture surfaces (shatter surfaces), and rare shatter cones are present near the center of the structure. We show that the dome formed mainly by centerward motion of rock units along listric faults. Outcrop-scale folding and upturning of beds, especially common in the center, are largely a consequence of this motion. We have also detected some centerward motion of fault-bounded wedges resulting from displacements on subhorizontal faults that conjoin and die out within horizontal bedding near the perimeter of the structure. The observed deformation corresponds to the central uplift and the encircling ring structural depression seen in complex impact craters. Copyright 1999 by the American Geophysical Union.

Computer-assisted system for the reconstruction of shattered objects

NASA Astrophysics Data System (ADS)

Cooper, Frederick A.; Brenningmeyer, Todd

2005-05-01

Reconstruction for forensic purposes of shattered or otherwise damaged objects has been a painstaking, if not impossible, undertaking. The forensic crime scientist and the archaeologist share this challenge. A pilot project, funded by the National Institute of Justice experimented with several avenues of approach to this problem of reassembly by using the 627 fragmented pieces of a pane of glass from a crime scene. I was approached by staff members of the Forensic Laboratory of the Minnesota Bureau of Criminal Apprehension because I was developing a means to restore a Greek Bronze Age wall painting (ca. 1350 B.C.E.) fragmented into 4750 pieces and a Greek temple (ca. 150 B.C.E.) demolished by vandals about 1500 years ago, leaving behind 1485 stone blocks, 1-3 tons each. The challenge was to develop an automated method to rapidly and effectively analyze a quantity of fragments of like kind separated one from the other and from the original object by violence and other means. The project established a set of mathematically and graphically definable characteristics held by the glass sherds which allowed for the making of joins between pieces. Preparation included the formulation of inventory check-sheets and a barcode label system with a unique identifier for each piece based on a x,y,z grid system. The next step involved experimentation with an array of proprietary GIS, SQL, and CAD software alternatives for the processing of data. In the end we settled on maximum likelihood analysis of SQL filtered results. This and shape indices were complied using ArcView and the scripting language, Avenue, products of ESRI, Redlands, California.

Partner verification: restoring shattered images of our intimates.

PubMed

De La Ronde, C; Swann, W B

1998-08-01

When spouses received feedback that disconfirmed their impressions of their partners, they attempted to undermine that feedback during subsequent interactions with these partners. Such partner verification activities occurred whether partners construed the feedback as overly favorable or overly unfavorable. Furthermore, because spouses tended to see their partners as their partners saw themselves, their efforts to restore their impressions of partners often worked hand-in-hand with partners' efforts to verify their own views. Finally, support for self-verification theory emerged in that participants were more intimate with spouses who verified their self-views, whether their self-views happened to be positive or negative.

Development of Chemical and Mechanical Cleaning Procedures for Genesis Solar Wind Samples

NASA Technical Reports Server (NTRS)

Schmeling, M.; Jurewicz, A. J. G.; Gonzalez, C.; Allums, K. K.; Allton, J. H.

2018-01-01

The Genesis mission was the only mission returning pristine solar material to Earth since the Apollo program. Unfortunately, the return of the spacecraft on September 8, 2004 resulted in a crash landing shattering the solar wind collectors into smaller fragments and exposing them to desert soil and other debris. Thorough surface cleaning is required for almost all fragments to allow for subsequent analysis of solar wind material embedded within. However, each collector fragment calls for an individual cleaning approach, as contamination not only varies by collector material but also by sample itself.

Reframing Romaine Brooks' heroic queer modernism.

PubMed

Langer, Cassandra L

2010-01-01

Modernism was not a wholesale embracing of Greenberg's definition as abstracting, non-objective, and autonomous. The expatriate U.S. artist and lesbian Romaine Brooks politicized her portraits of females based on a queer combination of the Byronic erotic and Baudelaire's modern dandy. Her execution of her queer modernist aesthetics re-presents female heroes as part of a self-reflective dynamic of lesbian modernity that emphasizes the ambiguity of normative gender binaries and plays with style, personality, and impersonation as disrupting to bourgeoisie mores. My focus is on how Brooks shatters normative conventions of portraiture in her revolutionary critique of heteronormativity.

To shatter the glass ceiling in healthcare management: who supports affirmative action and why?

PubMed

Weil, Peter A; Mattis, Mary C

2003-11-01

We examined the findings of a recent national survey of healthcare executives that showed 90% of women but only 53% of men favoured efforts to increase the proportion of women in senior healthcare management positions. Using the theories of relative deprivation and social identity, we tested hypotheses to suggest the background, work characteristics and attitudes about existing discriminatory practices in their own organizations that correlate with respondents' views about affirmative action for women. Some support is evidenced for the two theories and explanations are suggested to account for apparent anomalies.

Primitive processes, metaphor, and recognition in the treatment of traumatic loss.

PubMed

Ansorge, William

2012-12-01

This paper explores how traumatic loss and emotional abuse ruptured a patient's symbolic process and shattered her experience of the reality of her self. In treatment, metaphoric investigation of physical processes of expulsion and incorporation led to a transformation of projective identification into the containment she sought. The therapist's ability to metabolize pain, shame, and the risks of incestuous merger re-experienced in the treatment grew out of his recognition of disturbing experiences of his own that she brought to life. Mutual recognition, linked to the therapist's reverie, was a key treatment factor as both patient and therapist changed.

Multiple Stellar Populations in Star Clusters

NASA Astrophysics Data System (ADS)

Piotto, G.

2013-09-01

For half a century it had been astronomical dogma that a globular cluster (GC) consists of stars born at the same time out of the same material, and this doctrine has borne rich fruits. In recent years, high resolution spectroscopy and high precision photometry (from space and ground-based observations) have shattered this paradigm, and the study of GC populations has acquired a new life that is now moving it in new directions. Evidence of multiple stellar populations have been identified in the color-magnitude diagrams of several Galactic and Magellanic Cloud GCs where they had never been imagined before.

Modeling Dynamic Fracture of Cryogenic Pellets

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

Parks, Paul

This work is part of an investigation with the long-range objective of predicting the size distribution function and velocity dispersion of shattered pellet fragments after a large cryogenic pellet impacts a solid surface at high velocity. The study is vitally important for the shattered pellet injection (SPI) technique, one of the leading technologies being implemented at ORNL for the mitigation of disruption damage on current tokamaks and ITER. The report contains three parts that are somewhat interwoven. In Part I we formulated a self-similar model for the expansion dynamics and velocity dispersion of the debris cloud following pellet impact againstmore » a thick (rigid) target plate. Also presented in Part I is an analytical fracture model that predicts the nominal or mean size of the fragments in the debris cloud and agrees well with known SPI data. The aim of Part II is to gain an understanding of the pellet fracturing process when a pellet is shattered inside a miter tube with a sharp bend. Because miter tubes have a thin stainless steel (SS) wall a permanent deformation (dishing) of the wall is produced at the site of the impact. A review of the literature indicates that most projectile impact on thin plates are those for which the target is deformed and the projectile is perfectly rigid. Such impacts result in “projectile embedding” where the projectile speed is reduced to zero during the interaction so that all the kinetic energy (KE) of the projectile goes into the energy stored in plastic deformation. Much of the literature deals with perforation of the target. The problem here is quite different; the softer pellet easily undergoes complete material failure causing only a small transfer of KE to stored energy of wall deformation. For the real miter tube, we derived a strain energy function for the wall deflection using a non-linear (plastic) stress-strain relation for 304 SS. Using a dishing profile identical to the linear Kirchkoff-Love profile (for lack of a rigorously derived profile) we derived the strain energy associated with the deflection and applied a virtual work principle to find a relationship between the impact (load) pressure to the measured wall deflection depth. The inferred impact pressure was in good agreement with the expected pressure for oblique cryogenic pellet impacts where the pellet shear stress causing cleavage fracture is well above the yield stress for pure shear. The section is concluded with additional discussion on how this wall deformation data lends further support to the analytical fracture model presented in Part I. In Part III we present three different size distribution models. A summary, with a few brief suggestions for a follow on study, is provided at the end of this report.« less

Malaysian weedy rice shows its true stripes: wild Oryza and elite rice cultivars shape agricultural weed evolution in Southeast Asia.

PubMed

Song, Beng-Kah; Chuah, Tse-Seng; Tam, Sheh May; Olsen, Kenneth M

2014-10-01

Weedy rice is a close relative of domesticated rice (Oryza sativa) that competes aggressively with the crop and limits rice productivity worldwide. Most genetic studies of weedy rice have focused on populations in regions where no reproductively compatible wild Oryza species occur (North America, Europe and northern Asia). Here, we examined the population genetics of weedy rice in Malaysia, where wild rice (O. rufipogon) can be found growing in close proximity to cultivated and weedy rice. Using 375 accessions and a combined analysis of 24 neutral SSR loci and two rice domestication genes (sh4, controlling seed shattering, and Bh4, controlling hull colour), we addressed the following questions: (i) What is the relationship of Malaysian weedy rice to domesticated and wild rice, and to weedy rice strains in the USA? (ii) To what extent does the presence of O. rufipogon influence the genetic and phenotypic diversity of Malaysian weeds? (iii) What do the distributions of sh4 and Bh4 alleles and associated phenotypes reveal about the origin and contemporary evolution of Malaysian weedy rice? Our results reveal the following: independent evolutionary origins for Malaysian weeds and US strains, despite their very close phenotypic resemblance; wild-to-weed gene flow in Malaysian weed populations, including apparent adaptive introgression of seed-shattering alleles; and a prominent role for modern Malaysian cultivars in the origin and recent proliferation of Malaysian weeds. These findings suggest that the genetic complexity and adaptability of weedy crop relatives can be profoundly influenced by proximity to reproductively compatible wild and domesticated populations. © 2014 John Wiley & Sons Ltd.

The complex history of the domestication of rice.

PubMed

Sweeney, Megan; McCouch, Susan

2007-11-01

Rice has been found in archaeological sites dating to 8000 bc, although the date of rice domestication is a matter of continuing debate. Two species of domesticated rice, Oryza sativa (Asian) and Oryza glaberrima (African) are grown globally. Numerous traits separate wild and domesticated rices including changes in: pericarp colour, dormancy, shattering, panicle architecture, tiller number, mating type and number and size of seeds. Genetic studies using diverse methodologies have uncovered a deep population structure within domesticated rice. Two main groups, the indica and japonica subspecies, have been identified with several subpopulations existing within each group. The antiquity of the divide has been estimated at more than 100 000 years ago. This date far precedes domestication, supporting independent domestications of indica and japonica from pre-differentiated pools of the wild ancestor. Crosses between subspecies display sterility and segregate for domestication traits, indicating that different populations are fixed for different networks of alleles conditioning these traits. Numerous domestication QTLs have been identified in crosses between the subspecies and in crosses between wild and domesticated accessions of rice. Many of the QTLs cluster in the same genomic regions, suggesting that a single gene with pleiotropic effects or that closely linked clusters of genes underlie these QTL. Recently, several domestication loci have been cloned from rice, including the gene controlling pericarp colour and two loci for shattering. The distribution and evolutionary history of these genes gives insight into the domestication process and the relationship between the subspecies. The evolutionary history of rice is complex, but recent work has shed light on the genetics of the transition from wild (O. rufipogon and O. nivara) to domesticated (O. sativa) rice. The types of genes involved and the geographic and genetic distribution of alleles will allow scientists to better understand our ancestors and breed better rice for our descendents.

Eros is a Rubble Pile

NASA Astrophysics Data System (ADS)

Asphaug, Erik

2008-09-01

Asteroid 433 Eros is regarded as "fractured monolith" or "shatter pile". But models of fragmentation and disruption (e.g. Benz and Asphaug 1999) predict that any large rocky asteroid should be transformed into a jumble of dust, gravel, talus and boulders, simply because it is much easier to comminute an asteroid than to catastrophically disrupt it. Sometimes the relatively high density of Eros is taken as evidence for a fractured monolithic structure, although the inferred bulk porosity of Eros ( 20-30%) is what one expects for a rubble pile, and is about the porosity of sand and talus. The focus here is that a rubble pile structure is contraindicated by the pronounced network of linear fault-like structures (Buczkowski et al. 2008), some of which radiate from recent large impacts such as Psyche, and which form rectangular boundaries around some of the medium-sized craters. This needs an explanation. Here it is proposed, and quantitatively addressed, that the majority of these faults occur just in the upper tens of meters, where cohesion exceeds gravitational stress even for loose piles of lunar-like regolith. Assuming Eros regolith has the cohesion ( 1 kPa) measured for lunar regolith, then faulting is expected to a depth of 10 m, directly analogous to how faults occur in the upper layers of beach sand. The fact that Eros has few steep slopes anywhere, except for the angles of repose within its craters, at a baseline of 100 m (Zuber et al. 2002), is satisfied by the hypothesis that Eros is a rubble pile rather than a shattered monolith. The low fault stress implied by the above, supports the findings of dense networks of linear structures, ubiquitous features which are otherwise difficult to explain as fractures in a rocky target which has not been disrupted or jumbled against its very low gravity.

Cross-Modal Multivariate Pattern Analysis

PubMed Central

Meyer, Kaspar; Kaplan, Jonas T.

2011-01-01

Multivariate pattern analysis (MVPA) is an increasingly popular method of analyzing functional magnetic resonance imaging (fMRI) data1-4. Typically, the method is used to identify a subject's perceptual experience from neural activity in certain regions of the brain. For instance, it has been employed to predict the orientation of visual gratings a subject perceives from activity in early visual cortices5 or, analogously, the content of speech from activity in early auditory cortices6. Here, we present an extension of the classical MVPA paradigm, according to which perceptual stimuli are not predicted within, but across sensory systems. Specifically, the method we describe addresses the question of whether stimuli that evoke memory associations in modalities other than the one through which they are presented induce content-specific activity patterns in the sensory cortices of those other modalities. For instance, seeing a muted video clip of a glass vase shattering on the ground automatically triggers in most observers an auditory image of the associated sound; is the experience of this image in the "mind's ear" correlated with a specific neural activity pattern in early auditory cortices? Furthermore, is this activity pattern distinct from the pattern that could be observed if the subject were, instead, watching a video clip of a howling dog? In two previous studies7,8, we were able to predict sound- and touch-implying video clips based on neural activity in early auditory and somatosensory cortices, respectively. Our results are in line with a neuroarchitectural framework proposed by Damasio9,10, according to which the experience of mental images that are based on memories - such as hearing the shattering sound of a vase in the "mind's ear" upon seeing the corresponding video clip - is supported by the re-construction of content-specific neural activity patterns in early sensory cortices. PMID:22105246

Analyses Reveal Record-Shattering Global Warm Temperatures in 2015

NASA Image and Video Library

2017-12-08

2015 was the warmest year since modern record-keeping began in 1880, according to a new analysis by NASA’s Goddard Institute for Space Studies. The record-breaking year continues a long-term warming trend — 15 of the 16 warmest years on record have now occurred since 2001. Credits: Scientific Visualization Studio/Goddard Space Flight Center Details: Earth’s 2015 surface temperatures were the warmest since modern record keeping began in 1880, according to independent analyses by NASA and the National Oceanic and Atmospheric Administration (NOAA). Globally-averaged temperatures in 2015 shattered the previous mark set in 2014 by 0.23 degrees Fahrenheit (0.13 Celsius). Only once before, in 1998, has the new record been greater than the old record by this much. The 2015 temperatures continue a long-term warming trend, according to analyses by scientists at NASA’s Goddard Institute for Space Studies (GISS) in New York (GISTEMP). NOAA scientists agreed with the finding that 2015 was the warmest year on record based on separate, independent analyses of the data. Because weather station locations and measurements change over time, there is some uncertainty in the individual values in the GISTEMP index. Taking this into account, NASA analysis estimates 2015 was the warmest year with 94 percent certainty. Read more: www.nasa.gov/press-release/nasa-noaa-analyses-reveal-reco... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Shattering of SiMe3+ during surface-induced dissociation

NASA Astrophysics Data System (ADS)

Schultz, David G.; Hanley, Luke

1998-12-01

We provide experimental evidence that upon hyperthermal impact of Si(CD3)3+ ions with an organic surface, a portion of the ions undergo dissociation while still in contact with the surface. We use a tandem configuration of quadrupole mass spectrometers along with an energy analyzer to measure the kinetic energy distributions of the fragments that form as a result of the surface scattering of 25 eV Si(CD3)3+. These distributions are different for scattering from a clean Au(111) surface versus scattering from an organic surface composed of a self-assembled monolayer of hexanethiolate on Au(111). Parent and fragment ions recoil from the clean Au(111) surface with the same velocity, as is expected for fragmentation away from the surface. However, the same scattering products recoil from the organic surface with different velocities but similar energies, suggesting that the fragmentation dynamics are modified by surface interactions. We perform molecular dynamics simulations which predict residence times of ˜210 fs at the organic surface and ˜20 fs at the Au surface. The simulations also predict that 13% and 31% of the ions fragment within 1.1 ps of surface impact at the organic and Au surfaces, respectively. Thus, the experimental observation of dissociation at only the organic surface results from its longer ion-surface interaction time. The fragmentation time scale predicted by Rice-Ramsperger-Kassel-Marcus calculations is yet longer, suggesting that at least a portion of the surface-induced dissociation of Si(CD3)3+ may occur via a nonstatistical mechanism. Our interpretation draws heavily from an analogous "shattering" mechanism previously proposed for cluster-surface scattering [E. Hendell, U. Even, T. Raz, and R. D. Levine, Phys. Rev. Lett. 75, 2670 (1995)].

The road from The Microbial world to Microbe.

PubMed

Schaechter, Moselio; Ingraham, John L; Neidhardt, Frederick C

2007-09-01

The year 2007 commemorates the 50th anniversary of the publication of The Microbial World, the seminal microbiology textbook that shattered the microbiology world and whose first edition was coauthored by Roger Y. Stanier, Michael Doudoroff and Edward A. Adelberg. The year 2007 marks also twenty-five years of Stanier's passing away. The Spanish Society for Microbiology (SEM) with the support of Fundación Ramón Areces has organized a Symposium, in the frame of the 21st national congress of the SEM (Seville, 17-20 September 2007), to commemorate those anniversaries, and has invited us (Schaechter, Ingraham and Neidhardt) to contribute to this celebration.

Biological adhesives and fastening devices

NASA Astrophysics Data System (ADS)

Wolpert, H. D.

2012-04-01

Sea creatures are a leading source to some of the more interesting discoveries in adhesives. Because sea water naturally breaks down even the strongest conventional adhesive, an alternative is important that could be used in repairing or fabricating anything that might have regular contact with moisture such as: Repairing broken and shattered bones, developing a surgical adhesive, use in the dental work, repairing and building ships, and manufacturing plywood. Some of nature's prototypes include the common mussel, limpet, some bacteria and abalone. As we learn more about these adhesives we are also developing non adhesive fasteners, such as mimicked after studying the octopus, burdock burrs (i.e. Velcro®) and the gecko.

Simulated transient thermal infrared emissions of forest canopies during rainfall events

NASA Astrophysics Data System (ADS)

Ballard, Jerrell R.; Hawkins, William R.; Howington, Stacy E.; Kala, Raju V.

2017-05-01

We describe the development of a centimeter-scale resolution simulation framework for a theoretical tree canopy that includes rainfall deposition, evaporation, and thermal infrared emittance. Rainfall is simulated as discrete raindrops with specified rate. The individual droplets will either fall through the canopy and intersect the ground; adhere to a leaf; bounce or shatter on impact with a leaf resulting in smaller droplets that are propagated through the canopy. Surface physical temperatures are individually determined by surface water evaporation, spatially varying within canopy wind velocities, solar radiation, and water vapor pressure. Results are validated by theoretical canopy gap and gross rainfall interception models.

Remembering Pearl Harbor at 75 Years.

PubMed

Liehr, Patricia; Sopcheck, Janet; Milbrath, Gwyneth

2016-12-01

: On December 7, 1941, the Sunday-morning quiet of the U.S. naval base in Pearl Harbor, Hawaii, was shattered by dive-bombing Japanese fighter planes. The planes came in two waves-and when it was all over, more than 2,400 were killed and more than 1,100 were injured.Nurses were stationed at U.S. Naval Hospital Pearl Harbor, Tripler General Hospital (now Tripler Army Medical Center), Hickam Field Hospital, Schofield Barracks Station Hospital, and aboard the USS Solace, and witnessed the devastation. But they also did what nurses do in emergencies-they responded and provided care to those in need. Here are the stories of a few of those nurses.

Lox droplet vaporization in a supercritical forced convective environment

NASA Technical Reports Server (NTRS)

Hsiao, Chia-Chun; Yang, Vigor

1994-01-01

A systematic investigation has been conducted to study the effects of ambient flow conditions (i.e. pressure and velocity) on supercritical droplet gasification in a forced-convective environment. The model is based on the time-dependent conservation equations in axisymmetric coordinates, and accommodates thermodynamic nonidealities and transport anomalies. In addition, an efficient scheme for evaluating thermophysical properties over the entire range of fluid thermodynamic states is established. The analysis allows a thorough examination of droplet behavior during its entire lifetime, including transient gasification, dynamic deformation, and shattering. A parametric study of droplet vaporization rate in terms of ambient pressure and Reynolds number is also conducted.

The blossoms of loss: Ovid's floral metamorphoses and Poussin's realm of flora.

PubMed

Tutter, Adele

2014-07-01

Alluring and fertile, the flower connotes a locus of desire. The floral metamorphic myths narrated in Ovid's Metamorphoses (AD 8a) thematize the price of desire--the shame, grief, and rage of rejection and rivalrous defeat--and symbolize the generative transformation that frustrated desire and competitive loss can promote. In the deceptively beautiful painting Realm of Flora of 1631, Nicolas Poussin enlists these myths as allegories of his own great creative leap, an aesthetic metamorphosis that followed shattering defeats. Extending the association between creativity and object loss to competitive loss, Poussin holds a mirror to our powerful drive to prevail and create anew from the ashes of loss. © 2014 The Psychoanalytic Quarterly, Inc.

Arthur L. Schmeltekopf Jr. (1932-2007)

NASA Astrophysics Data System (ADS)

Howard, Carleton J.

2009-05-01

Arthur Louis Schmeltekopf Jr. died of mesothelioma, a lung cancer associated with exposure to asbestos, at his home in Marshall, N. C., on 20 August 2007. He was born on 24 February 1932, in Kyle, Tex., to Arthur L. and Meta (Engelbrecht) Schmeltekopf and grew up nearby on the family farm. Art had an early interest in science. A dispute over the reactivity of alkali metals toward water led to an experiment at Kyle High School involving a chunk of sodium metal and a toilet in the boys' room. The resulting explosion shattered the toilet, creating a flood, multiple geysers and panic in the nearby girls' room, a displaced lid on the school’s septic tank, and an enduring school legend.

Diversity, culture and the glass ceiling.

PubMed

Wilson, Eleanor

2014-01-01

A reference to the term, the glass ceiling, has come to embody more than gender equality among women and men. Today the term embraces the quest of all minorities and their journey towards equality in the workplace. The purpose of this article is to bring attention to the subject of diversity, culture, and the glass ceiling. The article will discuss the history of the glass ceiling and how its broadened meaning is relevant in today's workplace. It will also provide statistics showing how diversity and culture are lacking among the top echelon of today's executives, the barriers faced by minorities as they journey towards executive leadership, and how to overcome these barriers to truly shatter the glass ceiling.

Solar tests of aperture plate materials for solar thermal dish collectors

NASA Technical Reports Server (NTRS)

Jaffe, L. D.

1983-01-01

In parabolic dish solar collectors, walk-off of the spot of concentrated sunlight is a hazard if a malfunction causes the concentrator to stop following the Sun. Therefore, a test program was carried out to evaluate the behavior of various ceramics, metals, and polymers under solar irradiation of about 7000 kW/sq m. (peak) for 15 minutes. The only materials that did not slump or shatter were two grades of medium-grain extruded graphite. High purity, slip-cast silica might be satisfactory at somewhat lower flux. Oxidation of the graphite appeared acceptable during tests simulating walk-off, acquisition (2000 cycles on/off Sun), and spillage (continuous on-Sun operation).

Lithology and Bedrock Geotechnical Properties in Controlling Rock and Ice Mass Movements in Mountain Cryosphere

NASA Astrophysics Data System (ADS)

Karki, A.; Kargel, J. S.

2017-12-01

Landslides and ice avalanches kill >5000 people annually (D. Petley, 2012, Geology http://dx.doi.org/10.1130/G33217.1); destroy or damage homes and infrastructure; and create secondary hazards, such as flooding due to blocked rivers. Critical roles of surface slope, earthquake shaking, soil characteristics and saturation, river erosional undercutting, rainfall intensity, snow loading, permafrost thaw, freeze-thaw and frost shattering, debuttressing of unstable masses due to glacier thinning, and vegetation burn or removal are well-known factors affecting landslides and avalanches. Lithology-dependent bedrock physicochemical-mechanical properties—especially brittle elastic and shear strength, and chemical weathering properties that affect rock strength, are also recognized controls on landsliding and avalanching, but are not commonly considered in detail in landslide susceptibility assessment. Lithology controls the formation of weakened, weathered bedrock; the formation and accumulation of soils; soil saturation-related properties of grain size distribution, porosity, and permeability; and soil creep related to soil wetting-drying and freeze-thaw. Lithology controls bedrock abrasion and glacial erosion and debris production rates, the formation of rough or smoothed bedrock surface by glaciation, fluvial, and freeze-thaw processes. Lithologic variability (e.g., bedding; fault and joint structure) affects contrasts in chemical weathering rates, porosity, and susceptibility to frost shattering and chemical weathering, hence formation of overhanging outcrops and weakened slip planes. The sudden failure of bedrock or sudden slip of ice on bedrock, and many other processes depend on rock lithology, microstructure (porosity and permeability), and macrostructure (bedding; faults). These properties are sometimes considered in gross terms for landslide susceptibility assessment, but in detailed applications to specific development projects, and in detailed mapping over large areas, the details of rock lithology, weathering state, and structure are rarely considered. We have initiated a geological and rock mechanical properties approach to landslide susceptibility assessments in areas of high concern for human and infrastructure safety.

Solidification and Acceleration of Large Cryogenic Pellets Relevant for Plasma Disruption Mitigation

DOE PAGES

Combs, Stephen Kirk; Meitner, S. J.; Gebhart, T. E.; ...

2016-01-01

The technology for producing, accelerating, and shattering large pellets (before injection into plasmas) for disruption mitigation has been under development at the Oak Ridge National Laboratory for several years, including a system on DIII-D that has been used to provide some significant experimental results. The original proof-of-principle testing was carried out using a pipe gun injector cooled by a cryogenic refrig- erator (temperatures ~8-20 K) and equipped with a stainless steel tube to produce 16.5-mm pellets composed of either pure D 2, pure Ne, or a dual layer with a thin outer shell of D 2 and core of Ne.more » Recently, significant progress has been made in the laboratory using that same pipe gun and a new injector that is an ITER test apparatus cooled with liquid helium. The new injector operates at ~5-8 K, which is similar to temperatures expected with cooling provided by the flow of supercritical helium on ITER. An alternative technique for producing/solidifying large pellets directly from a premixed gas has now been successfully tested in the laboratory. Also, two additional pellet sizes have been tested recently (nominal 24.4 and 34.0 mm diameters). With larger pellets, the number of injectors required for ITER disruption mitigation can be reduced, resulting in less cost and a smaller footprint for the hardware. An attractive option is longer pellets, and 24.4-mm pellets with a length/diameter ratio of ~3 have been successfully tested. Since pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event, recent tests have concentrated on documenting the speeds with different hardware configurations and operating parameters; speeds of ~100-800 m/s have been recorded. The data and results from laboratory testing are presented and discussed, and a simple model for the pellet solidification process is described.« less

Ash Shutbah: A possible impact structure in Saudi Arabia

NASA Astrophysics Data System (ADS)

Gnos, Edwin; Hofmann, Beda A.; Schmieder, Martin; Al-Wagdani, Khalid; Mahjoub, Ayman; Al-Solami, Abdulaziz A.; Habibullah, Siddiq N.; Matter, Albert; Alwmark, Carl

2014-10-01

We have investigated the Ash Shutbah circular structure in central Saudi Arabia (21°37'N 45°39'E) using satellite imagery, field mapping, thin-section petrography, and X-ray diffraction of collected samples. The approximately 2.1 km sized structure located in flat-lying Jurassic Tuwaiq Mountain Limestone has been nearly peneplained by erosional processes. Satellite and structural data show a central area consisting of Dhruma Formation sandstones with steep bedding and tight folds plunging radially outward. Open folding occurs in displaced, younger Tuwaiq Mountain Limestone Formation blocks surrounding the central area, but is absent outside the circular structure. An approximately 60 cm thick, unique folded and disrupted orthoquartzitic sandstone marker bed occurring in the central area of the structure is found 140 m deeper in undisturbed escarpment outcrops located a few hundred meters west of the structure. With exception of a possible concave shatter cone found in the orthoquartzite of the central area, other diagnostic shock features are lacking. Some quartz-rich sandstones from the central area show pervasive fracturing of quartz grains with common concussion fractures. This deformation was followed by an event of quartz dissolution and calcite precipitation consistent with local sea- or groundwater heating. The combination of central stratigraphic uplift of 140 m, concussion features in discolored sandstone, outward-dipping concentric folds in the central area, deformation restricted to the rocks of the ring structure, a complex circular structure of 2.1 km diameter that appears broadly consistent with what one would expect from an impact structure in sedimentary targets, and a possible shatter cone all point to an impact origin of the Ash Shutbah structure. In fact, the Ash Shutbah structure appears to be a textbook example of an eroded, complex impact crater located in flat-lying sedimentary rocks, where the undisturbed stratigraphic section can be studied in escarpment outcrops in the vicinity of the structure.

Performance Stability of Silicone Oxide-Coated Plastic Parenteral Vials.

PubMed

Weikart, Christopher M; Pantano, Carlo G; Shallenberger, Jeff R

2017-01-01

A new packaging system was developed for parenteral pharmaceuticals that combines the best attributes of plastic and glass without their respective drawbacks. This technological advancement is based on the synergy between high-precision injection-molded plastics and plasma coating technology. The result is a shatter-resistant, optically clear, low-particulate, and chemically durable packaging system. The demand for this product is driven by the expanding market, regulatory constraints, and product recalls for injectable drugs and biologics packaged in traditional glass materials. It is shown that this new packaging system meets or exceeds the important performance characteristics of glass, especially in eliminating the glass delamination and breakage that has been observed in many products. The new packaging system is an engineered, multilayer, glass-coated plastic composite that provides a chemically stable contact surface and oxygen barrier performance that exceeds a 2 year shelf life requirement. Evaluation of the coating system characteristics and performance stability to chemical, temperature, and mechanical extremes are reported herein. LAY ABSTRACT: A new packaging system for parenteral pharmaceuticals was developed that combines the best attributes of plastic and glass without their respective drawbacks. This technological advancement is based on the synergy between high-precision injection-molded plastics and plasma coating technology. The result is a shatter-resistant, optically clear, low-particulate, and chemically durable packaging system. It is shown that this new packaging system meets or exceeds the important performance characteristics of glass, especially in eliminating the glass delamination and breakage that has been observed in many products. The new packaging system is an engineered, multilayer, glass-coated plastic composite that provides a chemically stable contact surface and oxygen barrier performance that exceeds a 2 year shelf life requirement. Evaluation of the coating system characteristics and performance stability to chemical, temperature, and mechanical extremes are reported herein. © PDA, Inc. 2017.

New Observations at the Slate Islands Impact Structure, Lake Superior

NASA Technical Reports Server (NTRS)

Dressler, B. O.; Sharpton, V. L.; Schnieders, B.; Scott, J.

1995-01-01

Slate Islands, a group of 2 large and several small islands, is located in northern Lake Superior, approximately 10 km south of Terrace Bay. Shatter cones, breccias and shock metamorphic features provide evidence that the Slate Islands Structure was formed as a result of asteroid or comet impact. Most of the island group is believed to represent the central uplift of a complex impact crater. The structure possibly has a diameter of about 32 km. For Sage (1978, 1991) shock metamorphic features, shatter cones and pervasive rock brecciation are the results of diatreme activity. The present investigations represent the second year of a co-operative study of the Lunar and Planetary Institute, Houston, Texas and the Field Services Section (Northwest) of the Ontario Geological Survey. The objective of this investigation is to come to a better understanding of the formation of mid-size impact structures on Earth and the planets of the solar system. Impact processes played a fundamental role in the formation of the planets and the evolution of life on Earth. Meteorite and comet impacts are not a phenomenon of the past. Last year, more than 20 pieces of the Shoemaker-Levy 9 impacted on Jupiter and the Tunguska comet impacted in Siberia in the early years of this century. The study of impact processes is a relatively young part of geoscience and much is still to be learnt by detailed field and laboratory investigations. The State Islands Structure has been selected for the present detailed investigations because of the excellent shoreline outcrops of rock units related to the impact. The structure is a complex impact crater that has been eroded so that important lithological and structural elements are exposed. We know of no other mid-size terrestrial impact structure with equal or better exposures. In this publication we present preliminary results of our 1994 and 1995 field and laboratory investigations. We have tentatively identified a few impact melt and a considerable number of suevite occurrences.

Monitoring Kilauea Volcano Using Non-Telemetered Time-Lapse Camera Systems

NASA Astrophysics Data System (ADS)

Orr, T. R.; Hoblitt, R. P.

2006-12-01

Systematic visual observations are an essential component of monitoring volcanic activity. At the Hawaiian Volcano Observatory, the development and deployment of a new generation of high-resolution, non- telemetered, time-lapse camera systems provides periodic visual observations in inaccessible and hazardous environments. The camera systems combine a hand-held digital camera, programmable shutter-release, and other off-the-shelf components in a package that is inexpensive, easy to deploy, and ideal for situations in which the probability of equipment loss due to volcanic activity or theft is substantial. The camera systems have proven invaluable in correlating eruptive activity with deformation and seismic data streams. For example, in late 2005 and much of 2006, Pu`u `O`o, the active vent on Kilauea Volcano`s East Rift Zone, experienced 10--20-hour cycles of inflation and deflation that correlated with increases in seismic energy release. A time-lapse camera looking into a skylight above the main lava tube about 1 km south of the vent showed an increase in lava level---an indicator of increased lava flux---during periods of deflation, and a decrease in lava level during periods of inflation. A second time-lapse camera, with a broad view of the upper part of the active flow field, allowed us to correlate the same cyclic tilt and seismicity with lava breakouts from the tube. The breakouts were accompanied by rapid uplift and subsidence of shatter rings over the tube. The shatter rings---concentric rings of broken rock---rose and subsided by as much as 6 m in less than an hour during periods of varying flux. Time-lapse imagery also permits improved assessment of volcanic hazards, and is invaluable in illustrating the hazards to the public. In collaboration with Hawaii Volcanoes National Park, camera systems have been used to monitor the growth of lava deltas at the entry point of lava into the ocean to determine the potential for catastrophic collapse.

Ion microprobe elemental analyses of impact features on interplanetary dust experiment sensor surfaces

NASA Technical Reports Server (NTRS)

Simon, Charles G.; Hunter, Jerry L.; Wortman, Jim J.; Griffis, Dieter P.

1992-01-01

Hypervelocity impact features from very small particles (less than 3 microns in diameter) on several of the electro-active dust sensors used in the Interplanetary Dust Experiment (IDE) were subjected to elemental analysis using an ion microscope. The same analytical techniques were applied to impact and containment features on a set of ultra-pure, highly polished single crystal germanium wafer witness plates that were mounted on tray B12. Very little unambiguously identifiable impactor debris was found in the central craters or shatter zones of small impacts in this crystalline surface. The surface contamination, ubiquitous on the surface of the Long Duration Exposure Facility, has greatly complicated data collection and interpretation from microparticle impacts on all surfaces.

From Shattered Assumptions to Weakened Worldviews: Trauma Symptoms Signal Anxiety Buffer Disruption.

PubMed

Edmondson, Donald; Chaudoir, Stephenie R; Mills, Mary Alice; Park, Crystal L; Holub, Julie; Bartkowiak, Jennifer M

2011-01-01

The fundamental assertion of worldview-based models of posttraumatic stress disorder is that trauma symptoms result when traumatic experiences cannot be readily assimilated into previously held worldviews. In two studies, we test the anxiety buffer disruption hypothesis, which states that trauma symptoms result from the disruption of normal death anxiety-buffering functions of worldview. In Study 1, participants with trauma symptoms greater than the cutoff for PTSD evinced greater death-thought accessibility than those with sub-clinical or negligible symptoms after a reminder of death. In Study 2, participants with clinically significant trauma symptoms showed no evidence of worldview defense though death-thoughts were accessible. These results support the anxiety buffer disruption hypothesis, and suggest an entirely new approach to experimental PTSD research.

The President's pleasant surprise: how LGBT advocates ended Don't Ask, Don't Tell.

PubMed

Frank, Nathaniel

2013-01-01

This study assesses the role of LGBT advocates in repealing the military's Don't Ask, Don't Tell policy in the U.S. Congress. It draws on the author's direct involvement with that effort as well as personal interviews and media evidence to consider the contributions of the Obama Administration, members of Congress, the media, and individuals and pressure groups in the repeal process. It argues that repeal succeeded not because of the effective implementation of a White House plan but because the pressure of LGBT advocates ultimately shattered several key obstacles including inadequate messaging and dysfunction and inertia among both politicians and interest groups in Washington. The article offers insight into the role of public pressure in forwarding social change.

Conducting a children's divorce group: one approach.

PubMed

Rich, Beverly Waldman; Molloy, Pat; Hart, Bernadette; Ginsberg, Susan; Mulvey, Trudy

2007-08-01

The disruptive period around the time of the divorce can shatter a child's entire living milieu. An 8-week experiential children's group incorporating art and creative activities as well as a concurrent parent group is described. The aim of treatment was to bolster children's abilities to communicate with parents and other caretakers. Overall, participants were observed to effectively release painful affect, communicate more openly, and identify strengths in their family systems. Yalom's therapeutic group factors were incorporated into the treatment model. The research of Davies and Cummings related to children in the context of family therapy was also considered. Group leaders included advance practice registered nurses. Follow-up objective data collected from participants might provide further information about the efficacy of the interventions.

Al Kushaymiyah as a target for a Colorado-type molybdenite deposit

USGS Publications Warehouse

Theobald, P.K.

1971-01-01

The granitic complex in the vicinity of Al Kushaymiyah was singled out by Whitlow (19,69, 1969a, 1971), as one of the most promising areas for exploration in the Southern Wajd quadrangle (Jackson and others, 1962). He noted in particular the intensity of shattering and silicification of these potassium-rich granites, and the presence of unusual concentrations of tungsten , molybdenum, and tin in samples from the area. In the light of shield-wide compilations, this area again stands out as the principal geochemical anomaly for the three metals. The similarity of these unusual geologic and geochemical features to those of Colorado-type molybdenite deposits is striking and suggests that the Al Kushaymiyah provides a favorableenvironment to explore for a stockwork molybdenum deposit.

Electric field controlled emulsion phase contactor

DOEpatents

Scott, Timothy C.

1995-01-01

A system for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity.

Method of using an electric field controlled emulsion phase contactor

DOEpatents

Scott, Timothy C.

1993-01-01

A system for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity.

Electric field controlled emulsion phase contactor

DOEpatents

Scott, T.C.

1995-01-31

A system is described for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity. 5 figs.

Sizing up the planets

NASA Technical Reports Server (NTRS)

Meszaros, S. P.

1985-01-01

Visual, scaled comparisons are made among prominent volcanic, tectonic, crater and impact basin features photographed on various planets and moons in the solar system. The volcanic formation Olympus Mons, on Mars, is 27 km tall, while Io volcanic plumes reach 200-300 km altitude. Valles Marineris, a tectonic fault on Mars, is several thousand kilometers long, and the Ithasa Chasma on the Saturnian moon Tethys extends two-thirds the circumference of the moon. Craters on the Saturnian moons Tethys and Mimas are large enough to suggest a collision by objects which almost shattered the planetoids. Large meteorite impacts may leave large impact basins or merely ripples, such as found on Callisto, whose icy surface could not support high mountains formed by giant body impacts.

Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor

DOEpatents

Scott, T.C.

1990-07-17

Methods and systems are disclosed for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a packing'' are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets. 2 figs.

Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor

DOEpatents

Scott, Timothy C.

1990-01-01

Methods and systems for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a "packing" are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets.

Coral reef management and conservation in light of rapidly evolving ecological paradigms.

PubMed

Mumby, Peter J; Steneck, Robert S

2008-10-01

The decline of many coral reef ecosystems in recent decades surprised experienced managers and researchers. It shattered old paradigms that these diverse ecosystems are spatially uniform and temporally stable on the scale of millennia. We now see reefs as heterogeneous, fragile, globally stressed ecosystems structured by strong positive or negative feedback processes. We review the causes and consequences of reef decline and ask whether management practices are addressing the problem at appropriate scales. We conclude that both science and management are currently failing to address the comanagement of extractive activities and ecological processes that drive ecosystems (e.g. productivity and herbivory). Most reef conservation efforts are directed toward reserve implementation, but new approaches are needed to sustain ecosystem function in exploited areas.

Occurrence of the saw-whet owl in Florida

USGS Publications Warehouse

Lesser, F.H.; Stickley, A.R.

1967-01-01

On 31 October 1965 at 1000 hours we observed and collected a Saw-whet Owl (Aegolius acadicus) in adult plumage and in apparently good physical condition at Ponte Vedra, St. Johns County, Florida. The bird flew from beneath a truck to a cross beam in a garage adjoining a large, fresh-water, wooded swamp dominated by cabbage palms (Sabal palmetto). We found a regurgitated pellet and a freshly killed, partially eaten cotton mouse (Peromyscus gossypinus) beneath the truck. The bird was sent to Henry M. Stevenson for deposit in Florida State University Museum, Tallahassee (specimen no. 4092b). Dr. Stevenson found that the skull had been shattered and the gonads destroyed in collecting. Total length (before skinning) was 210 mm.

Psychological adaptation among residents following restart of Three Mile Island.

PubMed

Prince-Embury, S; Rooney, J F

1995-01-01

Psychological adaptation is examined in a sample of residents who remained in the vicinity of Three Mile Island following the restart of the nuclear generating facility which had been shut down since the 1979 accident. Findings indicate a lowering of psychological symptoms between 1985 and 1989 in spite of increased lack of control, less faith in experts and increased fear of developing cancer. The suggestion is made that reduced stress might have been related to a process of adaptation whereby a cognition of emergency preparedness was integrated by some of these residents as a modulating cognitive element. Findings also indicate that "loss of faith in experts" is a persistently salient cognition consistent with the "shattered assumptions" theory of victimization.

The hydrodynamic theory of detonation

NASA Technical Reports Server (NTRS)

Langweiler, Heinz

1939-01-01

This report derives equations containing only directly measurable constants for the quantities involved in the hydrodynamic theory of detonation. The stable detonation speed, D, is revealed as having the lowest possible value in the case of positive material velocity, by finding the minimum of the Du curve (u denotes the speed of the gases of combustion). A study of the conditions of energy and impulse in freely suspended detonating systems leads to the disclosure of a rarefaction front traveling at a lower speed behind the detonation front; its velocity is computed. The latent energy of the explosive passes into the steadily growing detonation zone - the region between the detonation front and the rarefaction front. The conclusions lead to a new definition of the concept of shattering power. The calculations are based on the behavior of trinitrotoluene.

Exploiting Deep Eutectic Solvents and Organolithium Reagent Partnerships: Chemoselective Ultrafast Addition to Imines and Quinolines Under Aerobic Ambient Temperature Conditions.

PubMed

Vidal, Cristian; García-Álvarez, Joaquín; Hernán-Gómez, Alberto; Kennedy, Alan R; Hevia, Eva

2016-12-23

Shattering the long-held dogma that organolithium chemistry needs to be performed under inert atmospheres in toxic organic solvents, chemoselective addition of organolithium reagents to non-activated imines and quinolines has been accomplished in green, biorenewable deep eutectic solvents (DESs) at room temperature and in the presence of air, establishing a novel and sustainable access to amines. Improving on existing methods, this approach proceeds in the absence of additives; occurs without competitive enolization, reduction or coupling processes; and reactions were completed in seconds. Comparing RLi reactivities in DESs with those observed in pure glycerol or THF suggests a kinetic anionic activation of the alkylating reagents occurs, favoring nucleophilic addition over competitive hydrolysis. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Flying Lessons: Learning from Ryanair's Cost Reduction Culture

NASA Technical Reports Server (NTRS)

Lawton, Thomas C.

2000-01-01

Through radically improving the value equation for airline customers, Ryanair has served to shake-up established norms and practices in European aviation. Underpinning its price leadership and market success is a vigorous and relentless cost reduction ethos and resultant low break-even load factor. Ryanair has lowered European airline cost structures considerably, shattering existing cost floors. Few competitors are able to follow, either because they do not know how or they are unable due to social settlement obligations or service commitments. At the same time, the company has maintained high average load factors on its flights. Taken in conjunction with its low break-even load factor, this results in consistently high overall profit margins. On this basis, Ryanair is likely to remain a significant competitor and increase its market presence and success across Europe.

Geologic setting and petrology of Apollo 15 anorthosite /15415/.

NASA Technical Reports Server (NTRS)

Wilshire, H. G.; Schaber, G. G.; Jackson, E. D.; Silver, L. T.; Phinney, W. C.

1972-01-01

The geological setting, petrography and history of this Apollo 15 lunar rock sample are discussed, characterizing the sample as coarse-grained anorthosite composed largely of calcic plagioclase with small amounts of three pyroxene phases. The presence of shattered and granulated minerals in the texture of the rock is traced to two or more fragmentation events, and the presence of irregular bands of coarsely recrystallized plagioclase and minor pyroxene crossing larger plagioclase grains is traced to an earlier thermal metamorphic event. It is pointed out that any of these events may have affected apparent radiometric ages of elements in this rock. A comparative summarization of data suggests that this rock is the least-deformed member of a suite of similar rocks ejected from beneath the regolith at Spur crater.

Genesis: Removing Contamination from Sample Collectors

NASA Technical Reports Server (NTRS)

Lauer, H. V.; McNamara, K. M.; Westphal, Andrew; Butterworth, A. L.; Burnett, D. S.; Jurewicz, A.; Woolum, D.; Allton, J. H.

2005-01-01

The Genesis mission returned to Earth on September 8, 2004, experiencing a non-nominal reentry. The parachutes which were supposed to slow and stabilize the capsule throughout the return failed to deploy, causing the capsule to impact the desert floor at a speed of nearly 200 MPH. Both the science canister and the major components of the SRC were returned before nightfall on September 8 to the prestaged cleanroom at UTTR , avoiding prolonged exposure or pending weather changes which might further contaminate the samples. The majority of the contaminants introduced as a result of the anomalous landing were in the form of particulates, including UTTR dust and soil, carbon-carbon heat shield material, and shattered collector dust (primarily silicon and germanium). Additional information is included in the original extended abstract.

From Shattered Assumptions to Weakened Worldviews: Trauma Symptoms Signal Anxiety Buffer Disruption

PubMed Central

Edmondson, Donald; Chaudoir, Stephenie R.; Mills, Mary Alice; Park, Crystal L.; Holub, Julie; Bartkowiak, Jennifer M.

2013-01-01

The fundamental assertion of worldview-based models of posttraumatic stress disorder is that trauma symptoms result when traumatic experiences cannot be readily assimilated into previously held worldviews. In two studies, we test the anxiety buffer disruption hypothesis, which states that trauma symptoms result from the disruption of normal death anxiety-buffering functions of worldview. In Study 1, participants with trauma symptoms greater than the cutoff for PTSD evinced greater death-thought accessibility than those with sub-clinical or negligible symptoms after a reminder of death. In Study 2, participants with clinically significant trauma symptoms showed no evidence of worldview defense though death-thoughts were accessible. These results support the anxiety buffer disruption hypothesis, and suggest an entirely new approach to experimental PTSD research. PMID:24077677

Hunt for improved carbon capture picks up speed

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

None

A high-throughput metal-organic framework synthesis instrument in action. Berkeley Lab chemist Jeffrey Long's lab will soon host a round-the-clock, robotically choreographed hunt for carbon-hungry materials. The Berkeley Lab chemist leads a diverse team of scientists whose goal is to quickly discover materials that can efficiently strip carbon dioxide from a power plant's exhaust, before it leaves the smokestack and contributes to climate change. They're betting on a recently discovered class of materials called metal-organic frameworks, which boast a record-shattering internal surface area. A sugar cube-sized piece, if unfolded and flattened, would more than blanket a football field. The crystalline materialmore » can also be tweaked to absorb specific molecules. More: http://newscenter.lbl.gov/feature-stories/2010/05/26/carbon-capture-search/« less

X-ray computed tomography datasets for forensic analysis of vertebrate fossils.

PubMed

Rowe, Timothy B; Luo, Zhe-Xi; Ketcham, Richard A; Maisano, Jessica A; Colbert, Matthew W

2016-06-07

We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils.

Petrology of the Crystalline Rocks Hosting the Santa Fe Impact Structure

NASA Technical Reports Server (NTRS)

Schrader, C. M.; Cohen, B. A.

2010-01-01

We collected samples from within the area of shatter cone occurrence and for approximately 8 kilometers (map distance) along the roadway. Our primary goal is to date the impact. Our secondary goal is to use the petrology and Ar systematics to provide further insight into size and scale of the impact. Our approach is to: Conduct a detailed petrology study to identify lithologies that share petrologic characteristics and tectonic histories but with differing degrees of shock. Obtain micro-cores of K-bearing minerals from multiple samples for Ar-40/Ar-39 analysis. Examine the Ar diffusion patterns for multiple minerals in multiple shocked and control samples. This will help us to better understand outcrop and regional scale relationships among rocks and their responses to the impact event.

Crystallography Without Crystals: Determining the Structure of Individual Biological Molecules and Nanoparticles

ScienceCinema

Ourmazd, Abbas [University of Wisconsin, Milwaukee, Wisconsin, USA

2017-12-09

Ever shattered a valuable vase into 10 to the 6th power pieces and tried to reassemble it under a light providing a mean photon count of 10 minus 2 per detector pixel with shot noise? If you can do that, you can do single-molecule crystallography. This talk will outline how this can be done in principle. In more technical terms, the talk will describe how the combination of scattering physics and Bayesian algorithms can be used to reconstruct the 3-D diffracted intensity distribution from a collection of individual 2-D diffiraction patterns down to a mean photon count of 10 minus 2 per pixel, the signal level anticipated from the Linac Coherent Light Source, and hence determine the structure of individual macromolecules and nanoparticles.

Method of using an electric field controlled emulsion phase contactor

DOEpatents

Scott, T.C.

1993-11-16

A system is described for contacting liquid phases comprising a column for transporting a liquid phase contacting system, the column having upper and lower regions. The upper region has a nozzle for introducing a dispersed phase and means for applying thereto a vertically oriented high intensity pulsed electric field. This electric field allows improved flow rates while shattering the dispersed phase into many micro-droplets upon exiting the nozzle to form a dispersion within a continuous phase. The lower region employs means for applying to the dispersed phase a horizontally oriented high intensity pulsed electric field so that the dispersed phase undergoes continuous coalescence and redispersion while being urged from side to side as it progresses through the system, increasing greatly the mass transfer opportunity. 5 figures.

Catastrophic disruption experiments: Recent results

NASA Technical Reports Server (NTRS)

Martelli, G.; Ryan, E. V.; Nakamura, A. M.; Giblin, I.

1994-01-01

This paper presents a review of the progress in the field of catastrophic disruption experiments over the past 4 years, since the publication of the review paper by Fujiwara et al. (1989). We describe the development of new techniques to produce shattering impacts relevant to the study of the collisional evolution of the asteroids, and summarize the results from numerous experiments which have been performed to date, using a variety of materials for both the impactor and the targets. Some of these, such as ice-on-ice, loose aggregates and pressurized targets, are quite new and have provided novel and exciting results. Some of the gaps existing previously in the data on fragment ejection-angle distributions, as well as translational and rotational velocity fields (including fine fragments) have been filled, and these new results will be surveyed.

Shattered illusions: the effect of explicit memory mediation on an indirect memory test.

PubMed

Gooding, P A; Mayes, A R; Meudell, P R

1999-05-01

Four experiments were conducted to explore the possible involvement of explicit memory in an indirect memory test in which white noise accompanying old sentences was judged to be quieter than white noise accompanying new sentences (Jacoby, Allan, Collins & Larwill, 1988). Experiment 1 established that this effect lasted up to 1 week. Experiment 2 found that a group of amnesic patients showed a noise effect that was marginally above chance and not significantly less that that of their matched controls after a delay of one day. Effect of time pressure at test (Experiment 3) and divided attention at study (Experiment 4) suggested that the memory processes mediating the noise effect were not automatic, although the possibility that the processes involve enhanced fluency is also discussed.

Daredevils and early birds: Belgian pioneers in automobile racing and aerial sports during the belle époque.

PubMed

Ameye, Thomas; Gils, Bieke; Delheye, Pascal

2011-01-01

During the belle époque, Belgium was a trend-setting nation in many domains, including motorised sports. Belgian automobile racers and pilots shattered world records and became international stars. Striking was the shift in sports. Indeed, around 1896, sporting members of the leisure class stepped from the bicycle into the automobile and, around 1908, from the automobile into the airplane. Although these motorised sports were extremely expensive, this article shows that sportsmen and sportswomen from the working class could achieve upward social mobility through their performances. The achievements of these motorised pioneers had a major impact and wide-ranging significance. They laid the foundations for the expansion of the automobile industry and the emergence of civilian and military aviation.

X-ray computed tomography datasets for forensic analysis of vertebrate fossils

PubMed Central

Rowe, Timothy B.; Luo, Zhe-Xi; Ketcham, Richard A.; Maisano, Jessica A.; Colbert, Matthew W.

2016-01-01

We describe X-ray computed tomography (CT) datasets from three specimens recovered from Early Cretaceous lakebeds of China that illustrate the forensic interpretation of CT imagery for paleontology. Fossil vertebrates from thinly bedded sediments often shatter upon discovery and are commonly repaired as amalgamated mosaics grouted to a solid backing slab of rock or plaster. Such methods are prone to inadvertent error and willful forgery, and once required potentially destructive methods to identify mistakes in reconstruction. CT is an efficient, nondestructive alternative that can disclose many clues about how a specimen was handled and repaired. These annotated datasets illustrate the power of CT in documenting specimen integrity and are intended as a reference in applying CT more broadly to evaluating the authenticity of comparable fossils. PMID:27272251

A plutonic view of explosive volcanism: the shatter zone of the Cadillac Mountain granite, Maine

NASA Astrophysics Data System (ADS)

Wiebe, R.

2013-12-01

The Silurian Cadillac Mountain granite (CMG) is about 15 km in diameter. It is underlain on its deeper western margin by layered gabbro-diorite (GD) up to 3 km thick and on its eastern and southern margins by an intrusive breccia (the 'shatter zone' (SZ)), up to 1 km wide. Coeval rhyolite tuffs, ignimbrites and lavas occur near the southern margin of the granite. The more shallow eastern part of the SZ can be divided into three zones: (SZA) An outer zone against country rock (CR) consists of strongly broken up, deformed sedimentary rocks and angular blocks of diabase invaded by thin irregular veins of aphanitic felsite. All CR fragments are tightly packed with less than ~ 15% matrix, which coarsens inward to vfg quartz, feldspar and biotite. (SZB) A central zone contains abundant sedimentary and scarce rhyolite blocks (typically < 1 m) and larger diabase blocks (from < 1 m to 10s of meters). This zone has 20 to 60% fg to mg matrix with quartz, two feldspars, biotite and abundant pieces of CR down to a few mm. It typically has a strong flow fabric around CR blocks. (SZC) The inner zone has only large (10-80 m) blocks of sedimentary rock, diabase and rhyolite (flows and ignimbrite). The mg granitic matrix (>60%) has blocky hypersolvus feldspar, interstitial to equant quartz, Fe-cpx, Fe-hornblende, two oxides and scarce fayalite. Feldspar in this zone consistently has a sequence of zones consisting of: (1) a homogeneous core of ~ An10Ab80Or10, (2) a transition up to 1 mm wide with 10-15 Or-Ab oscillations (e.g. from Or10 to Or30), each from 20 to 100 microns in width, and (3) a nearly homogeneous rim of variable width averaging about An3Ab70Or27. The occurrence of crystals with such distinctive zoning over such a great distance (18 km) suggests that the zoning was produced by an intensive parameter and not by magma mixing. Because the crystals are restricted to the SZ matrix, processes that produced the shatter zone probably also influenced feldspar zoning. Analysis of clast size distribution of CR fragments in SZA and SZB suggests an extremely high-energy environment consistent with a pyroclastic eruption from the CMG magma chamber (Roy et al. 2012). If such an eruption did occur, one expected effect would be episodic, sudden drops in pressure during degassing and eruptive events. Since the lower part of the chamber was apparently relatively dry (hypersolvus alkali feldspar with ternary feldspar occurs in CMG immediately above the GD), the drop in pressure would lower H2O activity so that the Ab-rich loop of the alkali feldspar phase diagram would shift to higher T, causing the melt to fall below the liquidus and shift the equilibrium solid feldspar to higher Or values. This matches the initial oscillatory zone to higher Or on the homogeneous cores. Because the SZ terminates at the top of the GD, it is likely that mafic input contributed to the eruption. The large inward increase in the crystallization T of the matrix from SZA to SZC probably records initial escape of a cooler felsic cap and upwelling of deep, hot hypersolvus magma along with partial collapse of the chamber roof.

Gas Gun Model and Comparison to Experimental Performance of Pipe Guns Operating with Light Propellant Gases and Large Cryogenic Pellets

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

Reed, J. R.; Carmichael, J. R.; Gebhart, T. E.

Injection of multiple large (~10 to 30 mm diameter) shattered pellets into ITER plasmas is presently part of the scheme planned to mitigate the deleterious effects of disruptions on the vessel components. To help in the design and optimize performance of the pellet injectors for this application, a model referred to as “the gas gun simulator” has been developed and benchmarked against experimental data. The computer code simulator is a Java program that models the gas-dynamics characteristics of a single-stage gas gun. Following a stepwise approach, the code utilizes a variety of input parameters to incrementally simulate and analyze themore » dynamics of the gun as the projectile is launched down the barrel. Using input data, the model can calculate gun performance based on physical characteristics, such as propellant-gas and fast-valve properties, barrel geometry, and pellet mass. Although the model is fundamentally generic, the present version is configured to accommodate cryogenic pellets composed of H2, D2, Ne, Ar, and mixtures of them and light propellant gases (H2, D2, and He). The pellets are solidified in situ in pipe guns that consist of stainless steel tubes and fast-acting valves that provide the propellant gas for pellet acceleration (to speeds ~200 to 700 m/s). The pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event. The calculated speeds from the code simulations of experiments were typically in excellent agreement with the measured values. With the gas gun simulator validated for many test shots and over a wide range of physical and operating parameters, it is a valuable tool for optimization of the injector design, including the fast valve design (orifice size and volume) for any operating pressure (~40 bar expected for the ITER application) and barrel length for any pellet size (mass, diameter, and length). Key design parameters and proposed values for the pellet injectors for the ITER disruption mitigation systems are discussed.« less

Gas Gun Model and Comparison to Experimental Performance of Pipe Guns Operating with Light Propellant Gases and Large Cryogenic Pellets

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

Combs, S. K.; Reed, J. R.; Lyttle, M. S.

2016-01-01

Injection of multiple large (~10 to 30 mm diameter) shattered pellets into ITER plasmas is presently part of the scheme planned to mitigate the deleterious effects of disruptions on the vessel components. To help in the design and optimize performance of the pellet injectors for this application, a model referred to as “the gas gun simulator” has been developed and benchmarked against experimental data. The computer code simulator is a Java program that models the gas-dynamics characteristics of a single-stage gas gun. Following a stepwise approach, the code utilizes a variety of input parameters to incrementally simulate and analyze themore » dynamics of the gun as the projectile is launched down the barrel. Using input data, the model can calculate gun performance based on physical characteristics, such as propellant-gas and fast-valve properties, barrel geometry, and pellet mass. Although the model is fundamentally generic, the present version is configured to accommodate cryogenic pellets composed of H2, D2, Ne, Ar, and mixtures of them and light propellant gases (H2, D2, and He). The pellets are solidified in situ in pipe guns that consist of stainless steel tubes and fast-acting valves that provide the propellant gas for pellet acceleration (to speeds ~200 to 700 m/s). The pellet speed is the key parameter in determining the response time of a shattered pellet system to a plasma disruption event. The calculated speeds from the code simulations of experiments were typically in excellent agreement with the measured values. With the gas gun simulator validated for many test shots and over a wide range of physical and operating parameters, it is a valuable tool for optimization of the injector design, including the fast valve design (orifice size and volume) for any operating pressure (~40 bar expected for the ITER application) and barrel length for any pellet size (mass, diameter, and length). Key design parameters and proposed values for the pellet injectors for the ITER disruption mitigation systems are discussed.« less

Rock magnetic and paleomagnetic study of the Keurusselkä impact structure, central Finland

NASA Astrophysics Data System (ADS)

Raiskila, Selen; Salminen, Johanna; Elbra, Tiiu; Pesonen, Lauri J.

2011-11-01

There are 31 proven impact structures in Fennoscandia—one of the most densely crater-populated areas of the Earth. The recently discovered Keurusselkä impact structure (62°08' N, 24°37' E) is located within the Central Finland Granitoid Complex, which formed 1890-1860 Ma ago during the Svecofennian orogeny. It is a deeply eroded complex crater that yields in situ shatter cones with evidence of shock metamorphism, e.g., planar deformation features in quartz. New petrophysical and rock magnetic results of shocked and unshocked target rocks of various lithologies combined with paleomagnetic studies are presented. The suggested central uplift with shatter cones is characterized by increased magnetization and susceptibility. The presence of magnetite and pyrrhotite was observed as carriers for the remanent magnetization. Four different remanent magnetization directions were isolated: (1) a characteristic Svecofennian target rock component A with a mean direction of D = 334.8°, I = 45.6°, α95 = 14.9° yielding a pole (Plat = 51.1°, Plon = 241.9°, A95 = 15.1°), (2) component B, D = 42.4°, I = 64.1°, α95 = 8.4° yielding a pole (Plat = 61.0°, Plon = 129.1°, A95 = 10.6°), (3) component C (D = 159.5°, I = 65.4°, α95 = 10.7°) yielding a pole (Plat = 21.0°, Plon = 39.3°, A95 = 15.6°), and (4) component E (D = 275.5°, I = 62.0°, α95 = 14.4°) yielding a pole (Plat = 39.7°, Plon = 314.3°, A95 = 19.7°). Components C and E are considered much younger, possibly Neoproterozoic overprints, compared with the components A and B. The pole of component B corresponds with the 1120 Ma pole of Salla diabase dyke and is in agreement with the 40Ar/39Ar age of 1140 Ma from a pseudotachylitic breccia vein in a central part of the structure. Therefore, component B could be related to the impact, and thus represent the impact age.

Earth Observations taken by the Expedition 17 Crew

NASA Image and Video Library

2008-10-21

ISS017-E-020538 (21 Oct. 2008) --- Arkenu Craters 1 and 2 in Libya are featured in this image photographed by an Expedition 17 crewmember on the International Space Station. Geologists often study features on Earth, such as impact craters, to gain insight into processes that occur on other planets. On Earth, more than 150 impact craters have been identified on the continents, but only a few of these are classified as double impact craters. One such example, the Arkenu Craters in northern Africa, is shown in this image. Arkenu 1 and 2 are double impact structures located in eastern Libya (22.04 degrees north latitude and 23.45 degrees east longitude) in the Sahara desert, with diameters of approximately 6.8 kilometers and 10.3 kilometers, respectively. The craters are unusual in that they both exhibit concentric annular ridge structures (gray circles in the image indicate the position of the outermost visible ridges). In many terrestrial complex craters these features are highly eroded and no longer visible. While the circular structure of these features had been noted, the impact origin hypothesis was strengthened in December 2003 when a field team observed shatter cones -- conical-shaped features in rocks created by the high shock pressures generated during impact. Large outcrops of impact breccias -- a jumble of rock fragments generated at the impact site that are now cemented together into an identifiable rock layer -- were also observed by the field team. Two impactors, each approximately 500 meters in diameter, are thought to have created the craters. According to scientists, the age of the impact event has been dated as occurring less than 140 million years ago. While the presence of shatter cones and impact breccias is generally considered to be strong evidence for meteor impact, some scientists now question the interpretation of these features observed at the Arkenu structures and suggest that they were caused by erosive and volcanic processes. At present, both craters are being crossed by linear dunes extending northeast-southwest -- the superposition of the dunes across the annular ridges indicates that they are much younger than the craters.

On the influence of particle morphology on the post-impact ballistic response of ceramic armour materials

NASA Astrophysics Data System (ADS)

Hameed, Amer; Appleby-Thomas, Gareth; Wood, David; Jaansalu, Kevin

2015-06-01

Recent studies have shown evidence that the ballistic-resistance of fragmented (comminuted) ceramics is independent of the original strength of the material. In particular, experimental investigations into the ballistic behaviour of such fragmented ceramics have indicated that this response is correlated to shattered ceramic morphology. This suggests that careful control of ceramic microstructure - and therefore failure paths - might provide a route to optimise post-impact ballistic performance, thereby enhancing multi-hit capability. In this study, building on previous in-house work, ballistic tests were conducted using pre-formed `fragmented-ceramic' analogues based around three morphologically differing (but chemically identical) alumina feedstock materials compacted into target `pucks. In an evolution of previous work, variation of target thickness provided additional insight into an apparent morphology-based contribution to ballistic response.

Successful Beam-Beam Tuneshift Compensation

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

Bishofberger, Kip Aaron

2005-01-01

The performance of synchrotron colliders has been limited by the beam-beam limit, a maximum tuneshift that colliding bunches could sustain. Due to bunch-to-bunch tune variation and intra-bunch tune spread, larger tuneshifts produce severe emittance growth. Breaking through this constraint has been viewed as impossible for several decades. This dissertation introduces the physics of ultra-relativistic synchrotrons and low-energy electron beams, with emphasis placed on the limits of the Tevatron and the needs of a tuneshift-compensation device. A detailed analysis of the Tevatron Electron Lens (T EL) is given, comparing theoretical models to experimental data whenever possible. Finally, results of Tevatron operationsmore » with inclusion of the T EL are presented and analyzed. It is shown that the T EL provides a way to shatter the previously inescapable beam-beam limit.« less

Cracking a chemical conundrum

NASA Astrophysics Data System (ADS)

Adams, James M.; Ivanov, Alexandre S.; Johnson, Mark R.; Stride, John A.

2004-07-01

An everyday laboratory chemical, hexamethylbenzene (HMB) has assumed an important role in the history of molecular structure and crystallography. It was one of the first organic crystal structures to be solved and provided direct experimental proof for the hypothesis of planarity in aromatic systems. Very soon after this, HMB was found to undergo a phase transition at 117K, resulting in crystal shattering. Since then, many attempts have been made to obtain the low-temperature structure, but none have succeeded until now. Making use of the unique properties of the neutron, we have performed powder diffraction measurements to obtain the low-temperature crystal structure and inelastic measurements to determine the dynamics of the system. These experiments have been augmented by the use of ab initio calculations and molecular modelling to obtain a complete picture of HMB in the solid state.

Accidental cut-throat injuries from the broken windshield of an auto rickshaw: Two unusual cases.

PubMed

Swain, Rajanikanta; Dhaka, Shivani; Sharma, Munish; Bakshi, Mantaran Singh; Murty, O P; Sikary, Asit Kumar

2018-01-01

Accidental cut-throat injuries are extremely rare and usually involve a sharp-edged weapon. In this paper, two cases of a cut-throat wound to two auto-rickshaw drivers are presented where the broken windshield of the auto-rickshaws was responsible for the wounds. In both the cases, fatal incised wounds were present over the neck, cutting the soft tissue along with the major vessels. The death occurred due to exsanguination caused by neck-vessel injury in one case and trachea along with neck-vessel injury in the second case. Although the wounds on the neck initially suggested homicide, they were found to have occurred accidentally as a result of a road traffic accident involving a head-on collision of auto rickshaws. The injuries were inflicted by the shattered glass of the windshield.

Fistulectomy of the Parotid Fistula Secondary to Suppurative Parotitis: A Case Report

PubMed Central

Managutti, Anil; Tiwari, Saba; Prakasam, Michael; Puthanakar, Nagaraj

2015-01-01

A parotid fistula is a communication between the skin and a parotid duct or gland through which saliva is discharged. The most common cause of the parotid fistula is trauma. The major causes of parotid trauma in a civilian practice are penetrating injury to the parotid gland from an assault weapon or injury due to shattered glass after a motor vehicle accident. Acute suppurative parotitis can rarely produce a parotid fistula, and it will be difficult to manage successfully. In this article we have described diagnosis by fistulography, meticulous dissection, and complete excision of the fistulous tract with layered closure of the parotid fascia followed by application of a post-operative pressure bandage, use of anticholinergic agents and antibiotics contribute significantly to the successful management of this difficult clinical condition. PMID:25709371

Liquid-crystal science from 1888 to 1922: building a revolution.

PubMed

Mitov, Michel

2014-05-19

The saga of liquid crystals started with their discovery in 1888 by the botanist Friedrich Reinitzer, who unexpectedly observed "two melting points" for crystals extracted from the root of a carrot. At the end of the nineteenth century, most scientists did not believe in the existence of "liquid crystals" as promoted by the crystallographer Otto Lehmann. The controversies were very vivid; to the point that the recognition of mesomorphic states of matter by the scientific community required more than two decades. In the end, liquid crystals have changed our vision of matter by shattering the three-state paradigm. Since the mid-1970s, liquid crystals have revolutionized the worldwide information-display industry and now play a host of key roles in various technologies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Flynn Creek Impact Structure: New Insights from Breccias, Melt Features, Shatter Cones, and Remote Sensing

NASA Technical Reports Server (NTRS)

Evenick, J. C.; Lee, P.; Deane, B.

2004-01-01

The Flynn Creek impact structure is located in Tennessee, USA (36 deg.17 min.N, 85 deg.40 min.W). The structure was first mapped as a crypto-volcanic by Wilson and Born in 1936 [1]. Although they did not properly identify the stratigraphy within the crater or the causal mechanism, they did correctly define the horizontal extent of the crater. More detailed surface and subsurface research by Roddy (1979) accurately described the crater as being an impact structure with a diameter of 3.8 km. It formed around 360 Ma, which corresponds to the interval between the deposition of the Nashville Group and the Chattanooga Shale. Although there is limited rock outcrop in the area, there are exposed surface faults, folds, and large outcrops of impact breccia within the crater.

The Vredefort Dome: Review of geology and deformation phenomena and status report on current knowledge and remaining problematics (five years after the cryptoexplosion workshop)

NASA Technical Reports Server (NTRS)

Reimold, W. U.

1992-01-01

The Vredefort structure located in the center of the Witwatersrand basin in South Africa and the Sudbury structure in Canada are widely considered the two oldest and largest impact structures still evident on Earth. Both structures are very similar in a number of geological aspects (e.g., association with major economic ore deposits, similar ages of ca. 2 Ga, abundant pseudotachylite as well as shatter cone occurrences, overturned collar). However, whereas the geological community generally accepts an impact origin for the Sudbury structure, a number of researchers are still reluctant to accept this for the Vredefort Dome. Therefore, the aim of this review is to present new data, highlight the most obvious shortcomings in the current database, and to summarize the major arguments in the genetic controversy.

Microtubules in Plant Cells: Strategies and Methods for Immunofluorescence, Transmission Electron Microscopy and Live Cell Imaging

PubMed Central

Celler, Katherine; Fujita, Miki; Kawamura, Eiko; Ambrose, Chris; Herburger, Klaus; Wasteneys, Geoffrey O.

2016-01-01

Microtubules are required throughout plant development for a wide variety of processes, and different strategies have evolved to visualize and analyze them. This chapter provides specific methods that can be used to analyze microtubule organization and dynamic properties in plant systems and summarizes the advantages and limitations for each technique. We outline basic methods for preparing samples for immunofluorescence labelling, including an enzyme-based permeabilization method, and a freeze-shattering method, which generates microfractures in the cell wall to provide antibodies access to cells in cuticle-laden aerial organs such as leaves. We discuss current options for live cell imaging of MTs with fluorescently tagged proteins (FPs), and provide chemical fixation, high pressure freezing/freeze substitution, and post-fixation staining protocols for preserving MTs for transmission electron microscopy and tomography. PMID:26498784

“We, the AIDS people. . .”: How Antiretroviral Therapy Enables Zimbabweans Living With HIV/AIDS to Cope With Stigma

PubMed Central

Skovdal, Morten; Madanhire, Claudius; Mugurungi, Owen; Gregson, Simon; Nyamukapa, Constance

2011-01-01

We studied the impact of antiretroviral treatment availability on HIV/AIDS stigma through interviews with 118 antiretroviral treatment users, HIV/AIDS caregivers, and nurses in Zimbabwe. Treatment enables positive social and economic participation through which users can begin to reconstruct their shattered sense of social value. However, stigma remains strong, and antiretroviral treatment users remain mired in conflictual symbolic relationships between the HIV/AIDS people and the untested. To date, the restoration of users' own sense of self-worth through treatment has not reduced fear and sexual embarrassment in framing community responses to people living with HIV/AIDS. Much remains to be learned about the complex interaction of economic and psychosocial dimensions of poverty, treatment availability, and conservative sexual moralities in driving HIV/AIDS stigma in specific settings. PMID:21164081

Hemipelvectomy images of loss caused by war

PubMed Central

Salamon, Tal; Kassis, Shokrey; Lerner, Alexander

2014-01-01

As we treat our 230th patient from the Syrian conflict, the pathology we see is more debilitating and the humanitarian needs of the wounded have become even more obvious. This case presents some graphic images of the realities of war. Care in the most advanced units cannot restore broken limbs, let alone broken lives. We present a case of a young war-injured man, who suffered severe crush injury to the pelvis and lower limb, arriving at our medical facility after a delay of hours. The lower limb was shattered from the pelvis down (essentially a traumatic hemipelvectomy). His life had been saved in Syria by ligation of the femoral vessels in an unknown facility by an unknown medical team. On arrival in a centre in Israel for definitive care of an unsalvageable leg, formal hemipelvectomy was performed. PMID:25008336

Two cases of exenteration of the brain from Brenneke shotgun slugs.

PubMed

Karger, B; Banaschak, S

1997-01-01

A case of extended suicide resulted in two fatalities due to craniocerebral gunshots from a 12-gauge shotgun firing Brenneke shotgun slugs. In each case, the gunshot shattered the skull and the brain and in one case, large parts of the brain including a complete hemisphere were ejected similar to a "Krönlein shot". The location of the trajectory close to the base of the skull, the muzzle gases and the ballistic characteristics of the missile contributed to this rare form of head injury. The high mass and the large diameter of the lead missile do not necessitate a high muzzle velocity to crush large amounts of tissue or to produce an explosive type of head injury. The wadding material and the metal screw attached to the Brenneke slug can be of forensic significance.

Reactions to terror attacks in ultra-orthodox jews: the cost of maintaining strict identity.

PubMed

Ankri, Yael L E; Bachar, Eytan; Shalev, Arieh Y

2010-01-01

Traumatic events can shatter faith and beliefs. The responses of Ultra-Orthodox survivors of deadly terrorist attacks illustrate an effort to reconcile dreadful experiences with deeply embedded beliefs. Qualified clinicians prospectively evaluated self-reported and interviewer-generated posttraumatic stress disorder (PTSD) symptoms and cognitive appraisal in Ultra-Orthodox (n = 20) and non-Ultra-Orthodox (n = 33) survivors of suicide bus-bombing incidents in Jerusalem. Ultra-Orthodox survivors reported higher levels of PTSD symptoms and more personal guilt. Their narratives reflected an unshaken belief in Just Providence, within which being a victim of terror was perceived as a Just retribution for known or unknown wrongdoing. Survivors' reactions to trauma often reflect an effort to reconcile incongruous experiences with previously held beliefs. When treating strict believers, helpers should be sensitive to the identity-preserving function of posttraumatic cognitions.

Using large-scale genome variation cohorts to decipher the molecular mechanism of cancer.

PubMed

Habermann, Nina; Mardin, Balca R; Yakneen, Sergei; Korbel, Jan O

2016-01-01

Characterizing genomic structural variations (SVs) in the human genome remains challenging, and there is a growing interest to understand somatic SVs occurring in cancer, a disease of the genome. A havoc-causing SV process known as chromothripsis scars the genome when localized chromosome shattering and repair occur in a one-off catastrophe. Recent efforts led to the development of a set of conceptual criteria for the inference of chromothripsis events in cancer genomes and to the development of experimental model systems for studying this striking DNA alteration process in vitro. We discuss these approaches, and additionally touch upon current "Big Data" efforts that employ hybrid cloud computing to enable studies of numerous cancer genomes in an effort to search for commonalities and differences in molecular DNA alteration processes in cancer. Copyright © 2016. Published by Elsevier SAS.

ITER Disruption Mitigation System Design

NASA Astrophysics Data System (ADS)

Rasmussen, David; Lyttle, M. S.; Baylor, L. R.; Carmichael, J. R.; Caughman, J. B. O.; Combs, S. K.; Ericson, N. M.; Bull-Ezell, N. D.; Fehling, D. T.; Fisher, P. W.; Foust, C. R.; Ha, T.; Meitner, S. J.; Nycz, A.; Shoulders, J. M.; Smith, S. F.; Warmack, R. J.; Coburn, J. D.; Gebhart, T. E.; Fisher, J. T.; Reed, J. R.; Younkin, T. R.

2015-11-01

The disruption mitigation system for ITER is under design and will require injection of up to 10 kPa-m3 of deuterium, helium, neon, or argon material for thermal mitigation and up to 100 kPa-m3 of material for suppression of runaway electrons. A hybrid unit compatible with the ITER nuclear, thermal and magnetic field environment is being developed. The unit incorporates a fast gas valve for massive gas injection (MGI) and a shattered pellet injector (SPI) to inject a massive spray of small particles, and can be operated as an SPI with a frozen pellet or an MGI without a pellet. Three ITER upper port locations will have three SPI/MGI units with a common delivery tube. One equatorial port location has space for sixteen similar SPI/MGI units. Supported by US DOE under DE-AC05-00OR22725.

Wild emmer genome architecture and diversity elucidate wheat evolution and domestication.

PubMed

Avni, Raz; Nave, Moran; Barad, Omer; Baruch, Kobi; Twardziok, Sven O; Gundlach, Heidrun; Hale, Iago; Mascher, Martin; Spannagl, Manuel; Wiebe, Krystalee; Jordan, Katherine W; Golan, Guy; Deek, Jasline; Ben-Zvi, Batsheva; Ben-Zvi, Gil; Himmelbach, Axel; MacLachlan, Ron P; Sharpe, Andrew G; Fritz, Allan; Ben-David, Roi; Budak, Hikmet; Fahima, Tzion; Korol, Abraham; Faris, Justin D; Hernandez, Alvaro; Mikel, Mark A; Levy, Avraham A; Steffenson, Brian; Maccaferri, Marco; Tuberosa, Roberto; Cattivelli, Luigi; Faccioli, Primetta; Ceriotti, Aldo; Kashkush, Khalil; Pourkheirandish, Mohammad; Komatsuda, Takao; Eilam, Tamar; Sela, Hanan; Sharon, Amir; Ohad, Nir; Chamovitz, Daniel A; Mayer, Klaus F X; Stein, Nils; Ronen, Gil; Peleg, Zvi; Pozniak, Curtis J; Akhunov, Eduard D; Distelfeld, Assaf

2017-07-07

Wheat ( Triticum spp.) is one of the founder crops that likely drove the Neolithic transition to sedentary agrarian societies in the Fertile Crescent more than 10,000 years ago. Identifying genetic modifications underlying wheat's domestication requires knowledge about the genome of its allo-tetraploid progenitor, wild emmer ( T. turgidum ssp. dicoccoides ). We report a 10.1-gigabase assembly of the 14 chromosomes of wild tetraploid wheat, as well as analyses of gene content, genome architecture, and genetic diversity. With this fully assembled polyploid wheat genome, we identified the causal mutations in Brittle Rachis 1 ( TtBtr1 ) genes controlling shattering, a key domestication trait. A study of genomic diversity among wild and domesticated accessions revealed genomic regions bearing the signature of selection under domestication. This reference assembly will serve as a resource for accelerating the genome-assisted improvement of modern wheat varieties. Copyright © 2017, American Association for the Advancement of Science.

Mountain glaciation drives rapid oxidation of rock-bound organic carbon

PubMed Central

Horan, Kate; Hilton, Robert G.; Selby, David; Ottley, Chris J.; Gröcke, Darren R.; Hicks, Murray; Burton, Kevin W.

2017-01-01

Over millions of years, the oxidation of organic carbon contained within sedimentary rocks is one of the main sources of carbon dioxide to the atmosphere, yet the controls on this emission remain poorly constrained. We use rhenium to track the oxidation of rock-bound organic carbon in the mountain watersheds of New Zealand, where high rates of physical erosion expose rocks to chemical weathering. Oxidative weathering fluxes are two to three times higher in watersheds dominated by valley glaciers and exposed to frost shattering processes, compared to those with less glacial cover; a feature that we also observe in mountain watersheds globally. Consequently, we show that mountain glaciation can result in an atmospheric carbon dioxide source during weathering and erosion, as fresh minerals are exposed for weathering in an environment with high oxygen availability. This provides a counter mechanism against global cooling over geological time scales. PMID:28983510

Foam Core Shielding for Spacecraft

NASA Technical Reports Server (NTRS)

Adams, Marc

2007-01-01

A foam core shield (FCS) system is now being developed to supplant multilayer insulation (MLI) systems heretofore installed on spacecraft for thermal management and protection against meteoroid impacts. A typical FCS system consists of a core sandwiched between a face sheet and a back sheet. The core can consist of any of a variety of low-to-medium-density polymeric or inorganic foams chosen to satisfy application-specific requirements regarding heat transfer and temperature. The face sheet serves to shock and thereby shatter incident meteoroids, and is coated on its outer surface to optimize its absorptance and emittance for regulation of temperature. The back sheet can be dimpled to minimize undesired thermal contact with the underlying spacecraft component and can be metallized on the surface facing the component to optimize its absorptance and emittance. The FCS systems can perform better than do MLI systems, at lower mass and lower cost and with greater volumetric efficiency.

Tycho's Star Shines in Gamma Rays

NASA Image and Video Library

2017-12-08

NASA image relase December 13, 2011 Gamma-rays detected by Fermi's LAT show that the remnant of Tycho's supernova shines in the highest-energy form of light. This portrait of the shattered star includes gamma rays (magenta), X-rays (yellow, green, and blue), infrared (red) and optical data. Credit: Gamma ray, NASA/DOE/Fermi LAT Collaboration; X-ray, NASA/CXC/SAO; Infrared, NASA/JPL-Caltech; Optical, MPIA, Calar Alto, O. Krause et al. and DSS To read more go to: www.nasa.gov/mission_pages/GLAST/news/tycho-star.html NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Multiple-relaxation-time lattice Boltzmann method for immiscible fluids at high Reynolds numbers.

PubMed

Fakhari, Abbas; Lee, Taehun

2013-02-01

The lattice Boltzmann method for immiscible multiphase flows with large density ratio is extended to high Reynolds number flows using a multiple-relaxation-time (MRT) collision operator, and its stability and accuracy are assessed by simulating the Kelvin-Helmholtz instability. The MRT model is successful at damping high-frequency oscillations in the kinetic energy emerging from traveling waves generated by the inclusion of curvature. Numerical results are shown to be in good agreement with prior studies using adaptive mesh refinement techniques applied to the Navier-Stokes equations. Effects of viscosity and surface tension, as well as density ratio, are investigated in terms of the Reynolds and Weber numbers. It is shown that increasing the Reynolds number results in a more chaotic interface evolution and eventually shattering of the interface, while surface tension is shown to have a stabilizing effect.

Fluid Mechanics and Heat Transfer of Liquid Precursor Droplets Injected into High-Temperature Plasmas

NASA Astrophysics Data System (ADS)

Basu, Saptarshi; Jordan, Eric H.; Cetegen, Baki M.

2008-03-01

Thermo-physical processes in liquid ceramic precursor droplets in plasma were modeled. Models include aerodynamic droplet break-up, droplet transport, as well as heat and mass transfer within individual droplets. Droplet size, solute concentration, and plasma temperature effects are studied. Results are discussed with the perspective of selecting processing conditions and injection parameters to obtain certain types of coating microstructures. Small droplets (<5 microns) are found to undergo volumetric precipitation and coating deposition with small unpyrolized material. Droplets can be made to undergo shear break-up by reducing surface tension and small droplets promote volumetric precipitation. Small particles reach substrate as molten splats resulting in denser coatings. Model predicts that larger droplets (>5 microns) tend to surface precipitate-forming shells with liquid core. They may be subjected to internal pressurization leading to shattering of shells and secondary atomization of liquid within. They arrive at the substrate as broken shells and unpyrolized material.

Disappearance of a stutter shortly before death.

PubMed

Duong, Phuc H; Zulian, Gilbert B

2007-01-01

A patient with a stutter caused by the trauma of the death of a loved one was able to recover normal speech 1 week before her death, which resulted from intestinal obstruction caused by ovarian cancer. The stutter appeared to have been overcome using a combination therapy of sophrology, self-regulation, and drug therapy. During a genuine resilience process, the patient was able to overcome an earlier existential fracture. In this final phase of life, health professionals and the family fully respected the patient's independence to remain in control of events. She repeatedly refused to have a nasogastric tube inserted to extract fecal matter from the stomach. This patient consequently repossessed her own language of expression in a body that was shattered by cancerous illness and the consequences of treatments. She thus managed to find a successful balance between the body, the spirit, and the brain.

Explosive cell lysis as a mechanism for the biogenesis of bacterial membrane vesicles and biofilms

PubMed Central

Turnbull, Lynne; Toyofuku, Masanori; Hynen, Amelia L.; Kurosawa, Masaharu; Pessi, Gabriella; Petty, Nicola K.; Osvath, Sarah R.; Cárcamo-Oyarce, Gerardo; Gloag, Erin S.; Shimoni, Raz; Omasits, Ulrich; Ito, Satoshi; Yap, Xinhui; Monahan, Leigh G.; Cavaliere, Rosalia; Ahrens, Christian H.; Charles, Ian G.; Nomura, Nobuhiko; Eberl, Leo; Whitchurch, Cynthia B.

2016-01-01

Many bacteria produce extracellular and surface-associated components such as membrane vesicles (MVs), extracellular DNA and moonlighting cytosolic proteins for which the biogenesis and export pathways are not fully understood. Here we show that the explosive cell lysis of a sub-population of cells accounts for the liberation of cytosolic content in Pseudomonas aeruginosa biofilms. Super-resolution microscopy reveals that explosive cell lysis also produces shattered membrane fragments that rapidly form MVs. A prophage endolysin encoded within the R- and F-pyocin gene cluster is essential for explosive cell lysis. Endolysin-deficient mutants are defective in MV production and biofilm development, consistent with a crucial role in the biogenesis of MVs and liberation of extracellular DNA and other biofilm matrix components. Our findings reveal that explosive cell lysis, mediated through the activity of a cryptic prophage endolysin, acts as a mechanism for the production of bacterial MVs. PMID:27075392

Stretch, Shrink, and Shatter the Rhythms: The Intrinsic Circadian Period in Mania and Depression.

PubMed

Martynhak, Bruno Jacson; Pereira, Marcela; de Souza, Camila Pasquini; Andreatini, Roberto

2015-01-01

Disturbances in the circadian rhythms have long been associated with depression and mania. Animal models of mania and depression exhibit differential effects upon the intrinsic circadian period and the same occurs with antidepressants and mood stabilizers treatment. The intrinsic circadian period is expressed when there are no time clues or when the light/dark cycle length is beyond the capacity of synchronization. In summary, while there is no clear association between the circadian period and mania, depressive-like behaviour is generally associated either with lengthening of the circadian period or with arrythmicity, and the improvement of depressive-like behaviour is associated with shortening of the circadian period. Thus, this review is an attempt to summarize data regarding these correlations and find a putative role of the circadian intrinsic period in mood regulation, particularly concerning the switch from depression to mania.

Unavowed Abstention Can Overturn Poll Predictions

NASA Astrophysics Data System (ADS)

Galam, Serge

2018-03-01

I revisit the 2017 French Presidential election which opposed the far right National Front candidate Marine Le Pen against the center candidate Emmanuel Macron. While voting intentions for Le Pen stuck below 50% and polls kept predicting her failure, I warned on the emergence of a novel phenomenon I defined as unavowed abstention, which could suddenly reverse the ranking at Le Pen benefit on the voting day. My warning got a massive media coverage. She eventually lost the runoff at a score worse than predicted by the polls. Using a quantitative mathematical framing, which reveals the existence of tipping points in respective turnouts, I show that the predicted phenomenon of unavowed abstention did happen. But instead of shattering the expected outcome, against all odds it occurred at Le Pen expense, therefore without impact on the final outcome. The results shed a new light on other national cases such as Obama and Trump victories in the US.

Challenges towards Revitalizing Hemp: A Multifaceted Crop.

PubMed

Schluttenhofer, Craig; Yuan, Ling

2017-11-01

Hemp has been an important crop throughout human history for food, fiber, and medicine. Despite significant progress made by the international research community, the basic biology of hemp plants remains insufficiently understood. Clear objectives are needed to guide future research. As a semi-domesticated plant, hemp has many desirable traits that require improvement, including eliminating seed shattering, enhancing the quantity and quality of stem fiber, and increasing the accumulation of phytocannabinoids. Methods to manipulate the sex of hemp plants will also be important for optimizing yields of seed, fiber, and cannabinoids. Currently, research into trait improvement is hindered by the lack of molecular techniques adapted to hemp. Here we review how addressing these limitations will help advance our knowledge of plant biology and enable us to fully domesticate and maximize the agronomic potential of this promising crop. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Impact Crater in Coastal Patagonia

NASA Technical Reports Server (NTRS)

D'Antoni, Hector L; Lasta, Carlos A.; Condon, Estelle (Technical Monitor)

2000-01-01

Impact craters are geological structures attributed to the impact of a meteoroid on the Earth's (or other planet's) surface (Koeberl and Sharpton. 1999). The inner planets of the solar system as well as other bodies such as our moon show extensive meteoroid impacts (Gallant 1964, French 1998). Because of its size and gravity, we may assume that the Earth has been heavily bombarded but weathering and erosion have erased or masked most of these features. In the 1920's, a meteor crater (Mark 1987) was identified in Arizona and to this first finding the identification of a large number of impact structures on Earth followed (Hodge 1994). Shock metamorphic effects are associated with meteorite impact craters. Due to extremely high pressures, shatter cones are produced as well as planar features in quartz and feldspar grains, diaplectic glass and high-pressure mineral phases such as stishovite (French 1998).

Size of the top jet drop produced by bubble bursting

NASA Astrophysics Data System (ADS)

Berny, Alexis; Deike, Luc; Popinet, Stéphane; Seon, Thomas

2017-11-01

When a bubble is located on a liquid-air interface, it eventually bursts. First, the bubble cap shatters and produces film drops. Then, the cavity collapses, a tiny liquid jet rises and, depending on bubble radius and liquid parameters, it can eventually break-up and release the so-called jet drops. We perform numerical simulations, using the free software basilisk, to determine and discuss the regime of existence and the size of the first liquid jet droplets. We first validate the numerical scheme by comparing our results with recent experimental data. We then extend our numerical study to a wider range of control parameters in order to enrich our knowledge of the jet drops production. Finally, we show and interpret our results using a scaling law approach and basic physical arguments. This allows us to untangle the intricate roles of viscosity, gravity, and surface tension in the end pinching of the bubble bursting jet.

http://www.nasa.gov/feature/goddard/2016/hubble-team-breaks-cosmic-distance-record

NASA Image and Video Library

2016-03-03

By pushing NASA’s Hubble Space Telescope to its limits, an international team of astronomers has shattered the cosmic distance record by measuring the farthest galaxy ever seen in the universe. This surprisingly bright infant galaxy, named GN-z11, is seen as it was 13.4 billion years in the past, just 400 million years after the Big Bang. GN-z11 is located in the direction of the constellation of Ursa Major. Read more: go.nasa.gov/1oSqHad NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Multi-procedure management in an eyeglasses-related open globe injury

PubMed Central

Skopiński, Piotr; Langwińska-Wośko, Ewa; Korwin, Magdalena; Kołodziejczyk, Wojciech; Ambroziak, Anna Maria

2014-01-01

We present a case of successful multi-procedure management of a patient with an open globe injury. A 47-year-old man sustained an injury to his left eye caused by glass fragments of his own spectacles shattered while he was protecting an unknown woman from physical assault at a bus stop. Over a span of 65 months the patient underwent multiple procedures including primary wound repair, penetrating keratoplasty combined with extracapsular cataract extraction, neodymium: YAG laser capsulotomy, and laser-assisted subepithelial keratectomy (LASEK), and had a successfully treated episode of corneal graft rejection. This sequence of treatment substantially improved his left eye vision from hand movements at the time of admission to 0.9–0.5 × 90 at the last follow-up nearly 10 years after the trauma. Proper initial surgical management of an open globe injury can create the possibility for virtually complete vision restoration. PMID:24729818

Structural changes evaluation with Raman spectroscopy in meat batters prepared by different processes.

PubMed

Kang, Zhuang-Li; Li, Xiang; He, Hong-Ju; Ma, Han-Jun; Song, Zhao-Jun

2017-08-01

A comprehensive study was conducted to evaluate the structural changes of meat and protein of pork batters produced by chopping or beating process through the phase-contrast micrograph, laser light scattering analyzer, scanning electronic microscopy and Raman spectrometer. The results showed that the shattered myofibrilla fragments were shorter and particle-sizes were smaller in the raw batter produced by beating process than those in the chopping process. Compared with the raw and cooked batters produced by chopping process, modifications in amide I and amide III bands revealed a significant decrease of α -helix content and an increase of β -sheet, β -turn and random coils content in the beating process. The changes in secondary structure of protein in the batter produced by beating process was thermally stable. Moreover, more tyrosine residues were buried, and more gauche-gauche-trans disulfide bonds conformations and hydrophobic interactions were formed in the batter produced by beating process.

Massive Smash-up at Vega Artist Concept

NASA Image and Video Library

2005-01-10

This artist concept illustrates how a massive collision of objects perhaps as large as the planet Pluto smashed together to create the dust ring around the nearby star Vega. New observations from NASA's Spitzer Space Telescope indicate the collision took place within the last one million years. Astronomers think that embryonic planets smashed together, shattered into pieces, and repeatedly crashed into other fragments to create ever finer debris. In the image, a collision is seen between massive objects that measured up to 2,000 kilometers (about 1,200 miles) in diameter. Scientists say the big collision initiated subsequent collisions that created dust particles around the star that were a few microns in size. Vega's intense light blew these fine particles to larger distances from the star, and also warmed them to emit heat radiation that can be detected by Spitzer's infrared detectors. http://photojournal.jpl.nasa.gov/catalog/PIA07217

The Mechanics of Peak-Ring Impact Crater Formation from the IODP-ICDP Expedition 364

NASA Astrophysics Data System (ADS)

Melosh, H.; Collins, G. S.; Morgan, J. V.; Gulick, S. P. S.

2017-12-01

The Chicxulub impact crater is one of very few peak-ring impact craters on Earth. While small (less than 3 km on Earth) impact craters are typically bowl-shaped, larger craters exhibit central peaks, which in still larger (more than about 100 km on Earth) craters expand into mountainous rings with diameters close to half that of the crater rim. The origin of these peak rings has been contentious: Such craters are far too large to create in laboratory experiments and remote sensing of extraterrestrial examples has not clarified the mechanics of their formation. Two principal models of peak ring formation are currently in vogue, the "nested crater" model, in which the peak ring originates at shallow depths in the target, and the "dynamic collapse" model in which the peak ring is uplifted at the base of a collapsing, over-steepened central peak and its rocks originate at mid-crustal depths. IODP-ICDP Expedition 364 sought to elucidate, among other important goals, the mechanics of peak ring formation in the young (66 Myr), fresh, but completely buried Chicxulub impact crater. The cores from this borehole now show unambiguously that the rocks in the Chicxulub peak ring originated at mid-crustal depths, apparently ruling out the nested crater model. These rocks were shocked to pressures on the order of 10-35 GPa and were so shattered that their densities and seismic velocities now resemble those of sedimentary rocks. The morphology of the final crater, its structure as revealed in previous seismic imaging, and the results from the cores are completely consistent with modern numerical models of impact crater excavation and collapse that incorporate a model for post-impact weakening. Subsequent to the opening of a ca. 100 km diameter and 30 km deep transient crater, this enormous hole in the crust collapsed over a period of about 10 minutes. Collapse was enabled by movement of the underlying rocks, which briefly behaved in the manner of a high-viscosity fluid, a brittle deformation state described by the process of "acoustic" fluidization initiated by strong elastic vibrations accompanying the opening and collapse of the crater. The shattered core, cut by both melt rock and clastic dikes, is consistent with the block model of acoustic fluidization supporting its application to crater collapse both on the Earth and on other planets.

A statistical comparison of cirrus particle size distributions measured using the 2-D stereo probe during the TC4, SPARTICUS, and MACPEX flight campaigns with historical cirrus datasets

NASA Astrophysics Data System (ADS)

Schwartz, M. Christian

2017-08-01

This paper addresses two straightforward questions. First, how similar are the statistics of cirrus particle size distribution (PSD) datasets collected using the Two-Dimensional Stereo (2D-S) probe to cirrus PSD datasets collected using older Particle Measuring Systems (PMS) 2-D Cloud (2DC) and 2-D Precipitation (2DP) probes? Second, how similar are the datasets when shatter-correcting post-processing is applied to the 2DC datasets? To answer these questions, a database of measured and parameterized cirrus PSDs - constructed from measurements taken during the Small Particles in Cirrus (SPARTICUS); Mid-latitude Airborne Cirrus Properties Experiment (MACPEX); and Tropical Composition, Cloud, and Climate Coupling (TC4) flight campaigns - is used.Bulk cloud quantities are computed from the 2D-S database in three ways: first, directly from the 2D-S data; second, by applying the 2D-S data to ice PSD parameterizations developed using sets of cirrus measurements collected using the older PMS probes; and third, by applying the 2D-S data to a similar parameterization developed using the 2D-S data themselves. This is done so that measurements of the same cloud volumes by parameterized versions of the 2DC and 2D-S can be compared with one another. It is thereby seen - given the same cloud field and given the same assumptions concerning ice crystal cross-sectional area, density, and radar cross section - that the parameterized 2D-S and the parameterized 2DC predict similar distributions of inferred shortwave extinction coefficient, ice water content, and 94 GHz radar reflectivity. However, the parameterization of the 2DC based on uncorrected data predicts a statistically significantly higher number of total ice crystals and a larger ratio of small ice crystals to large ice crystals than does the parameterized 2D-S. The 2DC parameterization based on shatter-corrected data also predicts statistically different numbers of ice crystals than does the parameterized 2D-S, but the comparison between the two is nevertheless more favorable. It is concluded that the older datasets continue to be useful for scientific purposes, with certain caveats, and that continuing field investigations of cirrus with more modern probes is desirable.

Parameterizing Size Distribution in Ice Clouds

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

DeSlover, Daniel; Mitchell, David L.

2009-09-25

PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD).more » Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D < 100 µm) and underestimates of the mean and effective size of the PSD. Half of the cirrus cloud optical depth calculated from these in situ measurements can be due to this shattering phenomenon. Another challenge is the determination of ice and liquid water amounts in mixed phase clouds. Mixed phase clouds in the Arctic contain mostly liquid water, and the presence of ice is important for determining their lifecycle. Colder high clouds between -20 and -36 oC may also be mixed phase but in this case their condensate is mostly ice with low levels of liquid water. Rather than affecting their lifecycle, the presence of liquid dramatically affects the cloud optical properties, which affects cloud-climate feedback processes in GCMs. This project has made advancements in solving both of these problems. Regarding the first problem, PSD in ice clouds are uncertain due to the inability to reliably measure the concentrations of the smallest crystals (D < 100 µm), known as the “small mode”. Rather than using in situ probe measurements aboard aircraft, we employed a treatment of ice cloud optical properties formulated in terms of PSD parameters in combination with remote measurements of thermal radiances to characterize the small mode. This is possible since the absorption efficiency (Qabs) of small mode crystals is larger at 12 µm wavelength relative to 11 µm wavelength due to the process of wave resonance or photon tunneling more active at 12 µm. This makes the 12/11 µm absorption optical depth ratio (or equivalently the 12/11 µm Qabs ratio) a means for detecting the relative concentration of small ice particles in cirrus. Using this principle, this project tested and developed PSD schemes that can help characterize cirrus clouds at each of the three ARM sites: SGP, NSA and TWP. This was the main effort of this project. These PSD schemes and ice sedimentation velocities predicted from them have been used to test the new cirrus microphysics parameterization in the GCM known as the Community Climate Systems Model (CCSM) as part of an ongoing collaboration with NCAR. Regarding the second problem, we developed and did preliminary testing on a passive thermal method for retrieving the total water path (TWP) of Arctic mixed phase clouds where TWPs are often in the range of 20 to 130 g m-2 (difficult for microwave radiometers to accurately measure). We also developed a new radar method for retrieving the cloud ice water content (IWC), which can be vertically integrated to yield the ice water path (IWP). These techniques were combined to determine the IWP and liquid water path (LWP) in Arctic clouds, and hence the fraction of ice and liquid water. We have tested this approach using a case study from the ARM field campaign called M-PACE (Mixed-Phase Arctic Cloud Experiment). This research led to a new satellite remote sensing method that appears promising for detecting low levels of liquid water in high clouds typically between -20 and -36 oC. We hope to develop this method in future research.« less

Coal combustion system

DOEpatents

Wilkes, Colin; Mongia, Hukam C.; Tramm, Peter C.

1988-01-01

In a coal combustion system suitable for a gas turbine engine, pulverized coal is transported to a rich zone combustor and burned at an equivalence ratio exceeding 1 at a temperature above the slagging temperature of the coal so that combustible hot gas and molten slag issue from the rich zone combustor. A coolant screen of water stretches across a throat of a quench stage and cools the combustible gas and molten slag to below the slagging temperature of the coal so that the slag freezes and shatters into small pellets. The pelletized slag is separated from the combustible gas in a first inertia separator. Residual ash is separated from the combustible gas in a second inertia separator. The combustible gas is mixed with secondary air in a lean zone combustor and burned at an equivalence ratio of less than 1 to produce hot gas motive at temperature above the coal slagging temperature. The motive fluid is cooled in a dilution stage to an acceptable turbine inlet temperature before being transported to the turbine.

The Wells Creek Meteorite Impact Site and Changing Views on Impact Cratering

NASA Astrophysics Data System (ADS)

Ford, J. R. H.; Orchiston, Wayne; Clendening, Ron

2012-11-01

Wells Creek is a confirmed meteorite impact site in Tennessee, USA. The Wells Creek structure was first noticed by railroad surveyors around 1855 and brought to the attention of J.M. Safford, Tennessee's State Geologist. He included an insert in the 1869 Geologic Map of Tennessee, which is the first known map to include the structure. The origin of the Wells Creek structure was controversial, and was interpreted as being either the result of volcanic steam explosion or meteorite impact. It was only in the 1960s that Wilson and Stearns were able to state that the impact hypothesis was preferred. Evidence for a Wells Creek meteorite impact includes drill core results, extreme brecciation and shatter cones, while a local lack of volcanic material is telling. Just to the north of the Wells Creek Basin are three small basins that Wilson concluded were associated with the Wells Creek impact event, but evidence regarding the origin of the Austin, Indian Mound and Cave Spring Hollow sites is not conclusive.

'Clemency on the way to the gallows': death, dreams and dissociation.

PubMed

Kimmel, Kenneth

2017-11-01

The survivor of a decade of childhood sexual trauma and violence, perpetrated by a monstrous father, produced a series of dreams in the final year of a ten-year analysis. They illuminated the 'death drive' beneath a lifelong preoccupation with dying and fantasies of submission to death, perpetuated by the promise of hoped-for freedom from pain and release from a life of suffering. The initial dream involved the collapse of a team of white horses drawing him in a pillory cart to his own hanging for a crime he did not commit. It signified the collapse of a fragile psychological system based on his role as the 'sacrificial lamb,' protecting a (not so) innocent mother. The raw truth was now unconcealed: primal, violent, and terrifying dreams and affects emerged where he was now the murderous aggressor. His dreams would become primary agents for an instinctive, life-giving authenticity to emerge, offering him clemency from the shattering repetitions of persecution and dissociation. © 2017, The Society of Analytical Psychology.

Shock attenuation at the Slate Islands revisited

NASA Technical Reports Server (NTRS)

Wu, S.; Robertson, P. B.; Grieve, R. A. F.

1993-01-01

This study of a more extensive suite of Slate Islands samples confirms previous interpretations. It indicates clearly that recorded shock pressures, as determined by planar deformation feature orientations, increased towards the center. The 'shock center' is very close (considering the structural movements during cavity modification) to that from an independent determination from shatter cone orientations. Shock metamorphism at a higher level in breccia clasts than in the adjacent country rocks is evidence that the shock event preceded the formation of the breccia dikes. These observations, which are consistent with those at other impact structures, are all contrary to the interpretation by Sage that breccia dike formation by diatreme action was the source of the shock event. There is no plausible reason to consider the Slate Islands as anything but the emergent portion of the central uplift of a complex impact crater. It cannot be cited as an example of endogenic shock in arguments regarding evidence of impact in the terrestrial stratigraphic record.

Is there a false memory syndrome? A review of three cases.

PubMed

Kaplan, R; Manicavasagar, V

2001-01-01

The controversy over recovered memories of childhood sexual abuse (CSA) is whether such experiences can be forgotten for long periods and retrieved later in therapy or in response to cues or triggers from the environment. False memory syndrome (FMS) is caused by memories of a traumatic experience--most frequently CSA--which are objectively false, but in which the person strongly believes. Personality factors often play a role in the development of FMS. Because CSA is such a devastating experience, false accusations of sexual abuse have enormous, if not shattering, consequences for families. We present three case reports to illustrate features of the FMS. FMS should be listed for further study to establish valid criteria for making the diagnosis under the category of "factitious disorders," and a subcategory of "false memories/beliefs of abuse," with a further subdivision of "induced by therapy." The FMS controversy occurred in the context of a general moral panic about sexual abuse in the early 1980s. Psychiatrists should have a high degree of scepticism to moral panics.

Using artificial intelligence for automating testing of a resident space object collision avoidance system on an orbital spacecraft

NASA Astrophysics Data System (ADS)

Straub, Jeremy

2014-06-01

Resident space objects (RSOs) pose a significant threat to orbital assets. Due to high relative velocities, even a small RSO can cause significant damage to an object that it strikes. Worse, in many cases a collision may create numerous additional RSOs, if the impacted object shatters apart. These new RSOs will have heterogeneous mass, size and orbital characteristics. Collision avoidance systems (CASs) are used to maneuver spacecraft out of the path of RSOs to prevent these impacts. A RSO CAS must be validated to ensure that it is able to perform effectively given a virtually unlimited number of strike scenarios. This paper presents work on the creation of a testing environment and AI testing routine that can be utilized to perform verification and validation activities for cyber-physical systems. It reviews prior work on automated and autonomous testing. Comparative performance (relative to the performance of a human tester) is discussed.

Scientific Misconduct and the Myth of Self-Correction in Science.

PubMed

Stroebe, Wolfgang; Postmes, Tom; Spears, Russell

2012-11-01

The recent Stapel fraud case came as a shattering blow to the scientific community of psychologists and damaged both their image in the media and their collective self-esteem. The field responded with suggestions of how fraud could be prevented. However, the Stapel fraud is only one among many cases. Before basing recommendations on one case, it would be informative to study other cases to assess how these frauds were discovered. The authors analyze a convenience sample of fraud cases to see whether (social) psychology is more susceptible to fraud than other disciplines. They also evaluate whether the peer review process and replications work well in practice to detect fraud. There is no evidence that psychology is more vulnerable to fraud than the biomedical sciences, and most frauds are detected through information from whistleblowers with inside information. On the basis of this analysis, the authors suggest a number of strategies that might reduce the risk of scientific fraud. © The Author(s) 2012.

Cavitation onset caused by acceleration

PubMed Central

Pan, Zhao; Kiyama, Akihito; Tagawa, Yoshiyuki; Daily, David J.; Thomson, Scott L.; Hurd, Randy

2017-01-01

Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture. This observation indicates that the damaging phenomenon of cavitation is at fault. Cavitation is well known for causing damage in various applications including pipes and ship propellers, making accurate prediction of cavitation onset vital in several industries. However, the conventional cavitation number as a function of velocity incorrectly predicts the cavitation onset caused by acceleration. This unexplained discrepancy leads to the derivation of an alternative dimensionless term from the equation of motion, predicting cavitation as a function of acceleration and fluid depth rather than velocity. Two independent research groups in different countries have tested this theory; separate series of experiments confirm that an alternative cavitation number, presented in this paper, defines the universal criteria for the onset of acceleration-induced cavitation. PMID:28739956

All Along the Fractures

NASA Image and Video Library

2015-09-30

This image from NASA Mars Reconnaissance Orbiter spacecraft provides information about erosion and movement of surface material, about wind and weather patterns, even about the soil grains and grain sizes. However, looking past the dunes, these images also reveal the nature of the substrate beneath. Within the spaces between the dunes, a resistant and highly fractured surface is revealed. The fractured ground is resistant to erosion by the wind, and suggests the material is bedrock that is now shattered by a history of bending stresses or temperature changes, such as cooling, for example. Alternately, the surface may be a sedimentary layer that was once wet and shrunk and fractured as it dried, like gigantic mud cracks. In either case, the relative small and indistinct fractures have trapped the dark dune sand marching overhead. Now the fractures have become quite distinct, allowing us to examine the orientation and spacing of the fractures to learn more about the processes that formed them. http://photojournal.jpl.nasa.gov/catalog/PIA19958

Large Volume, Behaviorally-relevant Illumination for Optogenetics in Non-human Primates.

PubMed

Acker, Leah C; Pino, Erica N; Boyden, Edward S; Desimone, Robert

2017-10-03

This protocol describes a large-volume illuminator, which was developed for optogenetic manipulations in the non-human primate brain. The illuminator is a modified plastic optical fiber with etched tip, such that the light emitting surface area is > 100x that of a conventional fiber. In addition to describing the construction of the large-volume illuminator, this protocol details the quality-control calibration used to ensure even light distribution. Further, this protocol describes techniques for inserting and removing the large volume illuminator. Both superficial and deep structures may be illuminated. This large volume illuminator does not need to be physically coupled to an electrode, and because the illuminator is made of plastic, not glass, it will simply bend in circumstances when traditional optical fibers would shatter. Because this illuminator delivers light over behaviorally-relevant tissue volumes (≈ 10 mm 3 ) with no greater penetration damage than a conventional optical fiber, it facilitates behavioral studies using optogenetics in non-human primates.

Bone Morphogenetic Protein Usage in Anterior Lumbar Interbody Fusion: What Else Can Go Wrong?

PubMed

Elias, Elias; Nasser, Zeina; Winegan, Lona; Verla, Terence; Omeis, Ibrahim

2018-03-01

Bone morphogenetic protein (BMP) graft showed promising outcome during early phases of its use. However, unreported adverse events and off-label use shattered its safe profile and raised concerns regarding its indication. In 2008 the U.S. Food and Drug Administration prohibited its use in anterior cervical spine procedures due to the possibility of edema, hematoma, and need to intubate. At the molecular level, BMPs act as multifactorial growth factors playing a role in cartilage, heart, and bone formation. However, its unfavorable effect on bone overgrowth or heterotopic ossification post spine surgeries has been described. Reported cases in the literature were limited to epidural bone formation. We present a rare and interesting case of a 59-year-old female, in whom BMP caused intradural bone growth several years after an anterior lumbar interbody fusion surgery. Caution must be exercised while using BMPs because of inadvertent complications. Copyright © 2017 Elsevier Inc. All rights reserved.

NASA’s Hubble Sees Martian Moon Orbiting the Red Planet

NASA Image and Video Library

2017-12-08

While photographing Mars, NASA’s Hubble Space Telescope captured a cameo appearance of the tiny moon Phobos on its trek around the Red Planet. Discovered in 1877, the diminutive, potato-shaped moon is so small that it appears star-like in the Hubble pictures. Phobos orbits Mars in just 7 hours and 39 minutes, which is faster than Mars rotates. The moon’s orbit is very slowly shrinking, meaning it will eventually shatter under Mars’ gravitational pull, or crash onto the planet. Hubble took 13 separate exposures over 22 minutes to create a time-lapse video showing the moon’s orbital path. Credit: NASA, ESA, and Z. Levay (STScI) NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Volcano collapse promoted by progressive strength reduction: New data from Mount St. Helens

USGS Publications Warehouse

Reid, Mark E.; Keith, Terry E.C.; Kayen, Robert E.; Iverson, Neal R.; Iverson, Richard M.; Brien, Dianne

2010-01-01

Rock shear strength plays a fundamental role in volcano flank collapse, yet pertinent data from modern collapse surfaces are rare. Using samples collected from the inferred failure surface of the massive 1980 collapse of Mount St. Helens (MSH), we determined rock shear strength via laboratory tests designed to mimic conditions in the pre-collapse edifice. We observed that the 1980 failure shear surfaces formed primarily in pervasively shattered older dome rocks; failure was not localized in sloping volcanic strata or in weak, hydrothermally altered rocks. Our test results show that rock shear strength under large confining stresses is reduced ∼20% as a result of large quasi-static shear strain, as preceded the 1980 collapse of MSH. Using quasi-3D slope-stability modeling, we demonstrate that this mechanical weakening could have provoked edifice collapse, even in the absence of transiently elevated pore-fluid pressures or earthquake ground shaking. Progressive strength reduction could promote collapses at other volcanic edifices.

Establishing correspondence in wood: the challenge and some solutions?

PubMed

Courtin, Gerard M; Fairgrieve, Scott I

2013-09-01

Establishing correspondence between the upper portion of a white birch sapling, a suspected weapon, and a potential source from a stand of trees was posed to one of us (GMC). A bending force shattered the sapling, precluding physical matching. Three white birch saplings were taken from the same stand of trees in a similar manner. Correspondence was achieved by measuring the width of the annual rings along four radii from a disk cut above and below the break. The regression coefficient of the data from the two disks from the same sapling was r(2) = 0.95. Regressing the upper disk against the lower disk of two other saplings resulted in r(2) values of 0.26 and 0.17, respectively. The various characteristics that are confined to a wood stem as part of its normal process of growth can be used to eliminate candidate saplings and establish correspondence between two pieces of wood. © 2013 American Academy of Forensic Sciences.

Combined investigation of Eddy current and ultrasonic techniques for composite materials NDE

NASA Technical Reports Server (NTRS)

Davis, C. W.; Nath, S.; Fulton, J. P.; Namkung, M.

1993-01-01

Advanced composites are not without trade-offs. Their increased designability brings an increase in the complexity of their internal geometry and, as a result, an increase in the number of failure modes associated with a defect. When two or more isotropic materials are combined in a composite, the isotropic material failure modes may also combine. In a laminate, matrix delamination, cracking and crazing, and voids and porosity, will often combine with fiber breakage, shattering, waviness, and separation to bring about ultimate structural failure. This combining of failure modes can result in defect boundaries of different sizes, corresponding to the failure of each structural component. This paper discusses a dual-technology NDE (Non Destructive Evaluation) (eddy current (EC) and ultrasonics (UT)) study of graphite/epoxy (gr/ep) laminate samples. Eddy current and ultrasonic raster (Cscan) imaging were used together to characterize the effects of mechanical impact damage, high temperature thermal damage and various types of inserts in gr/ep laminate samples of various stacking sequences.

Mechanisms and Consequences of Double-strand DNA Break Formation in Chromatin

PubMed Central

Cannan, Wendy J.; Pederson, David S.

2016-01-01

All organisms suffer double-strand breaks (DSBs) in their DNA as a result of exposure to ionizing radiation. DSBs can also form when replication forks encounter DNA lesions or repair intermediates. The processing and repair of DSBs can lead to mutations, loss of heterozygosity, and chromosome rearrangements that result in cell death or cancer. The most common pathway used to repair DSBs in metazoans (non-homologous DNA end joining) is more commonly mutagenic than the alternative pathway (homologous recombination mediated repair). Thus, factors that influence the choice of pathways used DSB repair can affect an individual’s mutation burden and risk of cancer. This review describes radiological, chemical and biological mechanisms that generate DSBs, and discusses the impact of such variables as DSB etiology, cell type, cell cycle, and chromatin structure on the yield, distribution, and processing of DSBs. The final section focuses on nucleosome-specific mechanisms that influence DSB production, and the possible relationship between higher order chromosome coiling and chromosome shattering (chromothripsis). PMID:26040249

Cavitation onset caused by acceleration.

PubMed

Pan, Zhao; Kiyama, Akihito; Tagawa, Yoshiyuki; Daily, David J; Thomson, Scott L; Hurd, Randy; Truscott, Tadd T

2017-07-24

Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture. This observation indicates that the damaging phenomenon of cavitation is at fault. Cavitation is well known for causing damage in various applications including pipes and ship propellers, making accurate prediction of cavitation onset vital in several industries. However, the conventional cavitation number as a function of velocity incorrectly predicts the cavitation onset caused by acceleration. This unexplained discrepancy leads to the derivation of an alternative dimensionless term from the equation of motion, predicting cavitation as a function of acceleration and fluid depth rather than velocity. Two independent research groups in different countries have tested this theory; separate series of experiments confirm that an alternative cavitation number, presented in this paper, defines the universal criteria for the onset of acceleration-induced cavitation.

Cavitation onset caused by acceleration

NASA Astrophysics Data System (ADS)

Pan, Zhao; Kiyama, Akihito; Tagawa, Yoshiyuki; Daily, David J.; Thomson, Scott L.; Hurd, Randy; Truscott, Tadd T.

2017-08-01

Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture. This observation indicates that the damaging phenomenon of cavitation is at fault. Cavitation is well known for causing damage in various applications including pipes and ship propellers, making accurate prediction of cavitation onset vital in several industries. However, the conventional cavitation number as a function of velocity incorrectly predicts the cavitation onset caused by acceleration. This unexplained discrepancy leads to the derivation of an alternative dimensionless term from the equation of motion, predicting cavitation as a function of acceleration and fluid depth rather than velocity. Two independent research groups in different countries have tested this theory; separate series of experiments confirm that an alternative cavitation number, presented in this paper, defines the universal criteria for the onset of acceleration-induced cavitation.

Thinking outside the box - novel antibacterials to tackle the resistance crisis.

PubMed

Lakemeyer, Markus; Zhao, Weining; Mandl, Franziska A; Hammann, Peter; Sieber, Stephan Axel

2018-06-25

The public view on antibiotics as reliable medicine has changed when reports about "resistant superbugs" shattered the news. While reasons for this development are easily spotted, solutions for re-establishing effective antibiotics are still in their infancy. This review encompasses several aspects of the antibiotic development pipeline from very early strategies to mature drugs. We provide an interdisciplinary overview of methods suitable for mining novel antibiotics and discuss strategies to unravel their modes of action. Select examples of antibiotics recently identified using these platforms not only illustrate the efficiency of these measures, but also highlight promising clinical candidates with therapeutic potential. Furthermore, the concept of molecules that disarm pathogens by addressing gatekeepers of virulence will be covered. We conclude with an evaluation of antibacterials currently in clinical development. Overall, this review aims to connect select innovative antimicrobial approaches to stimulate interdisciplinary partnerships between chemists from academia and industry. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The behavior of a liquid drop levitated and drastically flattened by an intense sound field

NASA Technical Reports Server (NTRS)

Lee, C. P.; Anilkumar, A. V.; Wang, Taylor G.

1992-01-01

The deformation and break-up are studied of a liquid drop in levitation through the radiation pressure. Using high-speed photography ripples are observed on the central membrane of the drop, atomization of the membrane by emission of satellite drops from its unstable ripples, and shattering of the drop after upward buckling like an umbrella, or after horizontal expansion like a sheet. These effects are captured on video. The ripples are theorized to be capillary waves generated by the Faraday instability excited by the sound vibration. Atomization occurs whenever the membrane becomes so thin that the vibration is sufficiently intense. The vibration leads to a destabilizing Bernoulli correction in the static pressure. Buckling occurs when an existent equilibrium is unstable to a radial (i.e., tangential) motion of the membrane because of the Bernoulli effect. Besides, the radiation stress at the rim of the drop is a suction stress which can make equilibrium impossible, leading to the horizontal expansion and the subsequent break-up.

Effects of volcanism on the glaciers of Mount St. Helens

USGS Publications Warehouse

Brugman, Melinda M.; Post, Austin

1981-01-01

The cataclysmic eruption of Mount St. Helens May 18, 1980, removed 2.9 km2 (about 0.13 km3) of glacier snow and ice including a large part of Shoestring, Forsyth, Wishbone, Ape, Nelson, and all of Loowit and Leschi Glaciers. Minor eruptions and bulging of the volcano from March 27 to May 17 shattered glaciers which were on the deforming rock and deposited ash on other glaciers. Thick ash layers persisted after the May 18 eruption through the summer on most of the remaining snow and ice, and protected winter snow from melting on Swift and Dryer Glaciers. Melting and recrystalization of snow and ice surviving on Mount St. Helens could cause and lubricate mudflows and generate outburst floods. Study of glaciers that remain on this active volcano may assist in recognizing potential hazards on other volcanoes and lead to new contributions to knowledge of the transient response of glaciers to changes in mass balance or geometry.

Original Size and Shape of the Sudbury Structure

NASA Technical Reports Server (NTRS)

Lowman, P. D., Jr.

1997-01-01

This paper presents new evidence bearing on the original size and shape of the Sudbury impact structure. Current opinion is almost unanimous that the structure is a multiring basin with an original diameter of about 200 km and a circular shape that has since been shortened in a northwest-southeast direction by Penokean deformation Evidence for this interpretation, collected chiefly from north of the Sudbury Igneous Complex (SIC), includes supposed outer rings on Landsat imagery, distant occurrences of "Sudbury breccia" (generally defined as pseudotachylite), shatter cone occurrences, and outliers of Huronian sedimentary rock thought to be down-faulted rings. New data from imaging radar and field work north of the SIC, however, contradict this evidence. Radar imagery shows no signs of the supposed outer rings mapped by earlier workers on Landsat images. The most prominent ring has been found to be a chance alignment of two independent fracture sets. Radar imagery from the CCRS Convair 580, with look direction almost normal to the north rim of the SIC, shows no evidence of the rings despite strong look azimuth highlighting. Radar imagery has shown many unmapped diabase dikes north of the SIC. Several exposures of supposed Sudbury breccia are associated with these dikes or with Nipissing diabase intrusions, in some cases actually inside the dikes or directly continuous with them. They appear to be igneous intrusion breccias with no relation to impact. Shock-wave interaction at lithologic contacts cannot be invoked for most of these, because they are part of a northwest trending swarm cutting the SIC in the North Range, and hence too young for an impact origin. Similar diabase-related breccias and pseudotachylite-like veins have been found far outside the Sudbury area between Chapleau and Thessalon. Shatter cones north of the SIC are few and poorly developed, perhaps due to the coarse-grained Footwall rock, and cannot be considered a continuous zone analogous to their occurrence on the South Range in Huronian rocks. Supposed down-faulted outliers of Huronian rocks north of the SIC show no consistent relation to faulting, and the Huronian/Archean contact is locally erosional. Radar imagery and field-checking confirm Rousell's conclusion that the North Range has undergone little or no Penokean deformation. T'his implies that the plan view outline of the crater (floor of the SIC) is original. Extrapolation of the North Range as part of a circular arc leads to an impossibly great diameter. It is concluded that although Penokean deformation largely accounts for the structure's shape, the original crater was not circular and was much smaller than 200 km across.

Effects of target shape and impact speed on the outcome of catastrophic disruptions

NASA Astrophysics Data System (ADS)

Campo~Bagatin, A.; Durda, D.; Alemañ, R.; Flynn, G.; Strait, M.; Clayton, A.; Patmore, E.

2014-07-01

Because of the propensity of previous laboratory investigations to focus on idealized spherical targets, there is a bit of ambiguity in decoupling the relative importance/influence of low speed or spherical shape in producing the 'onion shell' fragment shape outcomes found in impacts into spherical targets [1,2]. If due primarily to impact speed/energy density as suggested by [3], this could play an important role in main-belt impacts due to the presence of non-spherical targets and non-negligible probability of low-speed (i.e., below about 3-4 km/s, subsonic in rock) impacts [4]. Also, [5] and [6] suggested that the shape of targets may affect the outcome of shattering processes, both in terms of fragment shape and mass distribution. To examine explicitly the effects of target shape in impact outcomes, we chose to conduct impact experiments on both spherical and naturally-occurring irregularly-shaped basalt targets. We impacted a total of six targets (two spheres and four irregular targets). We focused on shots with impact speeds in the ˜4 to 6 km/s range by 3/16th-inch diameter Al-sphere projectiles fired at the NASA AVGR. Following each shot, the debris were recovered (>95 %) and large fragments (>0.20 g) were individually weighed, allowing us to carefully measure the mass-frequency distribution from each impact experiment. The 36 largest fragments of each shot were photographed and their largest axes accurately measured by the program ''ImageJ''. Their shortest axes were measured by means of a digital caliber. High-speed video of each impact was obtained to aid interpretation of the fragmentation mode of the targets. Images clearly show that shell-like fragments can be produced in shattering events not in the target's surface. Instead, those fragments may form around the core, well inside the target structure, independently on the target shape itself. This is a feature not reported to date. In order to understand what the bulk macro-porosity of a non-coherent set of fragments is, we gathered randomly together the fragments with weighed mass mimicking the post-shattering gravitational re-accumulation of fragments into an asteroid rubble-pile. For each set, we wrapped the fragments in a thin plastic film and measured the bulk volume by hanging and plunging the assemblage into distilled water. The volume is calculated straightforward from the density of water at the given temperature. Cumulative mass distributions are derived and exponents 0.75<β <1.2 are found for the relationship N(>m)=A m^{-β} (m is the fragment mass, A is the corresponding constant) in the stationary part of the distribution. The exponent of each distribution and the mass of each largest fragment are found to be related to the corresponding specific energy of each impact as expected [3]. The mass distributions seem to show slightly larger values of β in the case of spherical targets when comparing two sets of close specific energy impacts. However, this feature needs further sets of impact experiments to be properly investigated. As for the shapes of fragments, b/a and c/a ratios were calculated along with the shape metrics Ψ=[ c^2/(ab)]^{1/3}, F=(a-b)/(a-c) for deviation from the spherical shape and relative flatness, respectively [7,8]. The average relationship between a, b, and c axes is 1:0.7:0.4, slightly different (flatter) than reported by former investigations (1:0.7:0.5) carried on in the 70s and 80s [7]. This result is quite stable and no differences are found in average shapes among spherical and irregular targets nor for different specific energy up to a factor of ˜3. This does not mean that fragments look like triaxial ellipsoids, instead they are quite irregular but their average relative sizes are distributed very nicely as described. Finally, the study of the macro-porosities of randomly aggregated fragments shows values in the 45 to 50 % range. This result may be useful in the interpretation of small asteroids' bulk densities and in the calibration of numerical modelling of internal structures.

Two war-torn soldiers: combat-related trauma through an intersubjective lens.

PubMed

Carr, Russell B

2013-01-01

The author, himself an Iraq war veteran, presents a contemporary psychodynamic understanding, known as intersubjective therapy, of combat-related Post-traumatic Stress Disorder (PTSD). At the onset of this case example, the patient was highly suicidal and his PTSD symptoms had not responded to a first-line treatment: manualized cognitive processing therapy. Robert Stolorow's intersubjective, psychodynamic approach to traumatic emotional experiences was then selected for treatment, and illustrates how combat in Afghanistan shattered this soldier's world and self experience. Therapeutic action arises from this intersubjective perspective by providing a relational home so that unendurable emotions can be borne, processed, and integrated to achieve a more constant and individualized sense of self. Being a two-person model of therapy, the author also describes how his work with this traumatized soldier affected him, ultimately contributing to his own sense of authentic existing. The author discusses the need for therapists to recognize and acknowledge to traumatized patients their shared finitude and the ubiquity of trauma. In the Postscript, the patient describes what he felt was therapeutic and contrasts this to his previous experiences with manualized cognitive processing therapy.

Dynamics of Protonated Peptide Ion Collisions with Organic Surfaces: Consonance of Simulation and Experiment

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

Pratihar, Subha; Barnes, George L.; Laskin, Julia

In this Perspective mass spectrometry experiments and chemical dynamics simulations are described which have explored the atomistic dynamics of protonated peptide ions, peptide-H+, colliding with organic surfaces. These studies have investigated surface-induced dissociation (SID) for which peptide-H+ fragments upon collision with the surface, peptide-H+ physisorption on the surface, soft landing (SL), and peptide-H+ reaction with the surface, reactive landing (RL). The simulations include QM+MM and QM/MM direct dynamics. For collisions with self-assembled monolayer (SAM) surfaces there is quite good agreement between experiment and simulation in the efficiency of energy transfer to the peptide-H+ ion’s internal degrees of freedom. Both themore » experiments and simulations show two mechanisms for peptide-H+ fragmentation, i.e. shattering and statistical, RRKM dynamics. Mechanisms for SL are probed in simulations of collisions of protonated dialanine with a perfluorinated SAM surface. RL has been studied experimentally for a number of peptide-H+ + surface systems, and qualitative agreement between simulation and experiment is found for two similar systems.« less

Evaluation of sonic IR for NDE at Lawrence Livermore National Laboratory

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

Miller, W O

2001-02-01

Sonic IR was evaluated as an NDE technique at LLNL using a commercial ThermoSoniX system from Indigo Systems Corp. The main effort was to detect small cracks in aluminum oxide, a dense stiff ceramic. Test coupons were made containing 0.2-mm cracks by surface grinding, 1-mm cracks by compression with a Vickers bit, and 4-mm cracks by 3-point bending. Only the 3-point bend cracks produced thermal images. Several parts shattered during testing, perhaps by being forced at resonance by the 20-kHz acoustic probe. Tests on damaged carbon composite coupons produced thermal images that were in excellent agreement with ultrasonic inspection. Themore » composite results also showed some dependence on contact location of the acoustic probe, and on the method of support. Tests on glass with surface damage produced weak images at the pits. Tests on metal ballistic targets produced thermal images at the impact sites. Modal analyses suggest that the input frequency should be matched to the desired response, and also that forced resonance damaged some parts.« less

"May all Be Shattered into God": Mary Barnes and Her Journey through Madness in Kingsley Hall.

PubMed

Chapman, Adrian

2018-06-02

Contributing to renewed scholarly interest in R. D. Laing and his circle, and in the radical therapeutic community of Kingsley Hall, London (1965-1970), this article offers the first article-length reading of Mary Barnes' and Joseph Berke's Mary Barnes: Two Accounts of a Journey through Madness. This text offers views of anti-psychiatry 'on the ground' that critique the 1960s utopianism of Laing's championing of madness as a metanoic, quasi-psychedelic voyage. Barnes' story, too, reveals tensions within the anti-psychiatric movement. Moving beyond existing criticism of the text, Barnes, it is argued here, emerges as far more than an exemplary patient, victim or anti-psychiatric puppet. Particular attention is paid in this reading of Two Accounts to the following: the ways in which the spiritually inclined Barnes and the psychoanalytic Berke differ in this dual narrative text; the ways in which each differs from Laing; the metaphor of the journey; and the setting of Barnes' story in the often conflicted, experimental household of Kingsley Hall.

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

Reason, J.

Transmission terminations available today are very reliable, but they need to be. In the field, they are continually exposed to pollution and extremes of ambient temperature. In many cases, they are in the rifle sights of vandals. In contrast, cable joints - often cited as the weakest links from an electrical viewpoint - are generally protected from physical damage underground and many of the short cable systems being installed in the US today can be built without joints. All cable systems need terminations - mostly to air-insulated equipment. At 69 through 138 kV, there is intense competition among manufacturers tomore » supply terminations for solid-dielectric cable that are low in cost, reliable, and require a minimum of skill to install. Some utilities are looking also for terminations that fit a range of cable sizes; terminations that do not contain liquid that can leak out; and terminations that are shatter-proof. All of these improvements are available in the US up to 69 kV. For higher voltages, they are on the horizon, if not already in use, overseas. 16 figs.« less

Modeling the relative contributions of secondary ice formation processes to ice crystal number concentrations within mixed-phase clouds

NASA Astrophysics Data System (ADS)

Sullivan, Sylvia; Hoose, Corinna; Nenes, Athanasios

2016-04-01

Measurements of in-cloud ice crystal number concentrations can be three or four orders of magnitude greater than the in-cloud ice nuclei number concentrations. This discrepancy can be explained by various secondary ice formation processes, which occur after initial ice nucleation, but the relative importance of these processes, and even the exact physics of each, is still unclear. A simple bin microphysics model (2IM) is constructed to investigate these knowledge gaps. 2IM extends the time-lag collision parameterization of Yano and Phillips, 2011 to include rime splintering, ice-ice aggregation, and droplet shattering and to incorporate the aspect ratio evolution as in Jensen and Harrington, 2015. The relative contribution of the secondary processes under various conditions are shown. In particular, temperature-dependent efficiencies are adjusted for ice-ice aggregation versus collision around -15°C, when rime splintering is no longer active, and the effect of aspect ratio on the process weighting is explored. The resulting simulations are intended to guide secondary ice formation parameterizations in larger-scale mixed-phase cloud schemes.

Roles of lignin biosynthesis and regulatory genes in plant development

PubMed Central

Yoon, Jinmi; Choi, Heebak

2015-01-01

Abstract Lignin is an important factor affecting agricultural traits, biofuel production, and the pulping industry. Most lignin biosynthesis genes and their regulatory genes are expressed mainly in the vascular bundles of stems and leaves, preferentially in tissues undergoing lignification. Other genes are poorly expressed during normal stages of development, but are strongly induced by abiotic or biotic stresses. Some are expressed in non‐lignifying tissues such as the shoot apical meristem. Alterations in lignin levels affect plant development. Suppression of lignin biosynthesis genes causes abnormal phenotypes such as collapsed xylem, bending stems, and growth retardation. The loss of expression by genes that function early in the lignin biosynthesis pathway results in more severe developmental phenotypes when compared with plants that have mutations in later genes. Defective lignin deposition is also associated with phenotypes of seed shattering or brittle culm. MYB and NAC transcriptional factors function as switches, and some homeobox proteins negatively control lignin biosynthesis genes. Ectopic deposition caused by overexpression of lignin biosynthesis genes or master switch genes induces curly leaf formation and dwarfism. PMID:26297385

Aligning a New Reference Genetic Map of Lupinus angustifolius with the Genome Sequence of the Model Legume, Lotus japonicus

PubMed Central

Nelson, Matthew N.; Moolhuijzen, Paula M.; Boersma, Jeffrey G.; Chudy, Magdalena; Lesniewska, Karolina; Bellgard, Matthew; Oliver, Richard P.; Święcicki, Wojciech; Wolko, Bogdan; Cowling, Wallace A.; Ellwood, Simon R.

2010-01-01

We have developed a dense reference genetic map of Lupinus angustifolius (2n = 40) based on a set of 106 publicly available recombinant inbred lines derived from a cross between domesticated and wild parental lines. The map comprised 1090 loci in 20 linkage groups and three small clusters, drawing together data from several previous mapping publications plus almost 200 new markers, of which 63 were gene-based markers. A total of 171 mainly gene-based, sequence-tagged site loci served as bridging points for comparing the Lu. angustifolius genome with the genome sequence of the model legume, Lotus japonicus via BLASTn homology searching. Comparative analysis indicated that the genomes of Lu. angustifolius and Lo. japonicus are highly diverged structurally but with significant regions of conserved synteny including the region of the Lu. angustifolius genome containing the pod-shatter resistance gene, lentus. We discuss the potential of synteny analysis for identifying candidate genes for domestication traits in Lu. angustifolius and in improving our understanding of Fabaceae genome evolution. PMID:20133394

Superheated fuel injection for combustion of liquid-solid slurries

DOEpatents

Robben, Franklin A.

1985-01-01

A method and device for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal.

Analytical modeling of operating characteristics of premixing-prevaporizing fuel-air mixing passages. Volume 1: Analysis and results

NASA Technical Reports Server (NTRS)

Anderson, O. L.; Chiappetta, L. M.; Edwards, D. E.; Mcvey, J. B.

1982-01-01

A model for predicting the distribution of liquid fuel droplets and fuel vapor in premixing-prevaporizing fuel-air mixing passages of the direct injection type is reported. This model consists of three computer programs; a calculation of the two dimensional or axisymmetric air flow field neglecting the effects of fuel; a calculation of the three dimensional fuel droplet trajectories and evaporation rates in a known, moving air flow; a calculation of fuel vapor diffusing into a moving three dimensional air flow with source terms dependent on the droplet evaporation rates. The fuel droplets are treated as individual particle classes each satisfying Newton's law, a heat transfer, and a mass transfer equation. This fuel droplet model treats multicomponent fuels and incorporates the physics required for the treatment of elastic droplet collisions, droplet shattering, droplet coalescence and droplet wall interactions. The vapor diffusion calculation treats three dimensional, gas phase, turbulent diffusion processes. The analysis includes a model for the autoignition of the fuel air mixture based upon the rate of formation of an important intermediate chemical species during the preignition period.

A Nanohelicoidal Nematic Liquid Crystal Formed by a Non-Linear Duplexed Hexamer.

PubMed

Mandle, Richard J; Goodby, John W

2018-06-11

The twist-bend modulated nematic liquid-crystal phase exhibits formation of a nanometre-scale helical pitch in a fluid and spontaneous breaking of mirror symmetry, leading to a quasi-fluid state composed of chiral domains despite being composed of achiral materials. This phase was only observed for materials with two or more mesogenic units, the manner of attachment between which is always linear. Non-linear oligomers with a H-shaped hexamesogen are now found to exhibit both nematic and twist-bend modulated nematic phases. This shatters the assumption that a linear sequence of mesogenic units is a prerequisite for this phase, and points to this state of matter being exhibited by a wider range of self-assembling structures than was previously envisaged. These results support the double helix model of the TB phase as opposed to the simple heliconical model. This new class of materials could act as low-molecular-weight surrogates for cross-linked liquid-crystalline elastomers. © 2018 Die Autoren. Veröffentlicht von Wiley-VCH Verlag GmbH & Co. KGaA.

Dreams Fulfilled and Shattered: Determinants of Segmented Assimilation in the Second Generation*

PubMed Central

Haller, William; Portes, Alejandro; Lynch, Scott M.

2013-01-01

We summarize prior theories on the adaptation process of the contemporary immigrant second generation as a prelude to presenting additive and interactive models showing the impact of family variables, school contexts and academic outcomes on the process. For this purpose, we regress indicators of educational and occupational achievement in early adulthood on predictors measured three and six years earlier. The Children of Immigrants Longitudinal Study (CILS), used for the analysis, allows us to establish a clear temporal order among exogenous predictors and the two dependent variables. We also construct a Downward Assimilation Index (DAI), based on six indicators and regress it on the same set of predictors. Results confirm a pattern of segmented assimilation in the second generation, with a significant proportion of the sample experiencing downward assimilation. Predictors of the latter are the obverse of those of educational and occupational achievement. Significant interaction effects emerge between these predictors and early school contexts, defined by different class and racial compositions. Implications of these results for theory and policy are examined. PMID:24223437

Evidence of the impacting body of the Ries crater - the discovery of Fe-Cr-Ni veinlets below the crater bottom

USGS Publications Warehouse

El, Goresy A.; Chao, E.C.T.

1976-01-01

Fe-Cr-Ni particles and veinlets have been discovered in the top 15 m of the compressed zone with abundant shatter cones below the bottom of the Ries crater. The metallic particles are less than a few microns across. They occur in various minerals along healed intergranular and locally in intragranular microfractures in quartz diorite, amphibolite and chloritized granite of the basement crystalline rocks. The particles consist of major Fe, Cr, and Ni with minor Si and Ca. Origin due to contamination is absolutely ruled out. We believe that these Fe-Cr-Ni particles are probably condensed from the vaporized impacting body which produced the Ries crater. These particles were injected with high velocity into microfractures near the top of the compressed zone, implanted in and across various minerals before these microfractures were resealed. The presence of Si and Ca as well as the fact that the Cr content is nearly twice that of Ni, led us to conclude that the Ries impacting body is very likely not an iron meteorite but a stony meteorite. ?? 1976.

[Effect of CO2 laser on prostheses used in middle ear surgery].

PubMed

Szymański, Marcin

2005-01-01

The use of CO2 laser is advocated in primary and revision stapes surgery. The aim of the study was to assess the effect of CO2 laser on stapes prostheses. CO2 laser was applied on several types of stapes prostheses and PORPs, with power settings suggested by the manufacturer (continuous wave, 2 W and 6 W; 0,05 s). Application of the laser on stainless steel or titanium prosthesis did not exert any effect on the structure of the prosthesis. The use of the laser on the Teflon piston caused superficial burning with power 2 W, and melting and holes in the piston with power settings at 6W. Similar plastipore prostheses were melting. Hydroxyapatite PORP shattered after application of the laser energy. Teflon and hydroxyapatite prostheses are easily damaged by the laser energy, therefore applying a laser on them should be avoided. CO2 laser can be used on stainless steel and titanium prostheses without risk of damaging them. However the possibility of transmission of heat to the vestibule has to be taken into consideration.

Shattered, Suffering, and Silenced: Sharon's Story.

PubMed

Shafer, Michaela R

2016-01-01

This chapter presents a case study of a 30-year-old female news reporter in Albuquerque, New Mexico, named Sharon Fullilove. The case is presented as a personal narrative by her mother, who is a critical care nurse, former chief nurse, Level I trauma unit commander, and colonel in the U.S. Air Force. The narrative is followed by excerpts from Sharon's chart that confirm a series of decisions made by both the hospital and the providers. The subsequent narrative is meant to give the reader an opportunity to reflect on the variety of clinical ethics questions that emerge when a patient enters into a contract with a physician and hospital for care. The goal is not to perform a thorough ethical analysis of the case but to let the reader experience what it is like when best practice standards, attention to patient care, and compassionate concern for family members are set aside. The case concludes with a set of broad questions that can be used for further discussion. Hopefully, this case will bring to the forefront the centrality of ethics in professional decision-making within the context of medical care.

Geophysics of Volcanic Landslide Hazards: The Inside Story

NASA Astrophysics Data System (ADS)

Finn, C.; Deszcz-Pan, M.; Bedrosian, P. A.

2013-05-01

Flank collapses of volcanoes pose significant potential hazards, including triggering lahars, eruptions, and tsunamis. Significant controls on the stability of volcanoes are the distribution of hydrothermal alteration and the location of groundwater. Groundwater position, abundance, and flow rates within a volcano affect the transmission of fluid pressure and the transport of mass and heat. Interaction of groundwater with acid magmatic gases can lead to hydrothermal alteration that mechanically weakens rocks and makes them prone to failure and flank collapse. Therefore, detecting the presence and volume of hydrothermally altered rocks and shallow ground water is critical for evaluating landslide hazards. High-resolution helicopter magnetic and electromagnetic (HEM) data collected over the rugged, ice-covered Mount Adams, Mount Baker, Mount Rainier, Mount St. Helens (Washington) and Mount Iliamna (Alaska) volcanoes, reveal the distribution of alteration, water and ice thickness essential to evaluating volcanic landslide hazards. These data, combined with geological mapping, other geophysical data and rock property measurements, indicate the presence of appreciable thicknesses (>500 m) of water-saturated hydrothermally altered rock west of the modern summit of Mount Rainier in the Sunset Amphitheater region and in the central core of Mount Adams north of the summit. Water-saturated alteration at Mount Baker is restricted to thinner (<200 m) zones beneath Sherman Crater and the Dorr Fumarole Fields. The HEM data can be used to identify water-saturated fresh volcanic rocks from the surface to the detection limit (~100-200 m) in discreet zones on the summits of Mount Rainier and Mt Adams, in shattered fresh dome rocks under the crater of Mount St. Helens and in the entire summit region at Mount Baker. A 50-100 m thick water saturated layer is imaged within or beneath parts of glaciers on Mount Iliamna. Removal of ice and snow during eruptions and landslide can result in lahars and floods. Ice thickness measurements critical for flood and mudflow hazards studies are very sparse on most volcanoes. The HEM data are used to estimate ice thickness over portions of Mount Baker and Mount Adams volcanoes. The best estimates for ice thickness are obtained over relatively low resistivity (<600 ohm-m) ground for the main ice cap on Mount Adams and over most of the summit of Mount Baker. The modeled distribution of alteration, pore fluids and partial ice volumes on the volcanoes helps identify likely sources for future alteration-related debris flows, including the Sunset Amphitheater region at Mount Rainier, steep cliffs at the western edge of the central altered zone at Mount Adams, south and north flanks of Mount Baker, and central Mount Iliamna. The water saturated shattered fresh dome material in the crater of Mount St. Helens may have served as part of the slip surface for the 1980 debris avalanche.

Superheated fuel injection for combustion of liquid-solid slurries

DOEpatents

Robben, F.A.

1984-10-19

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

Dynamical origins of the community structure of an online multi-layer society

NASA Astrophysics Data System (ADS)

Klimek, Peter; Diakonova, Marina; Eguíluz, Víctor M.; San Miguel, Maxi; Thurner, Stefan

2016-08-01

Social structures emerge as a result of individuals managing a variety of different social relationships. Societies can be represented as highly structured dynamic multiplex networks. Here we study the dynamical origins of the specific community structures of a large-scale social multiplex network of a human society that interacts in a virtual world of a massive multiplayer online game. There we find substantial differences in the community structures of different social actions, represented by the various layers in the multiplex network. Community sizes distributions are either fat-tailed or appear to be centered around a size of 50 individuals. To understand these observations we propose a voter model that is built around the principle of triadic closure. It explicitly models the co-evolution of node- and link-dynamics across different layers of the multiplex network. Depending on link and node fluctuation probabilities, the model exhibits an anomalous shattered fragmentation transition, where one layer fragments from one large component into many small components. The observed community size distributions are in good agreement with the predicted fragmentation in the model. This suggests that several detailed features of the fragmentation in societies can be traced back to the triadic closure processes.

The emotions of graduating medical students about prior patient care experiences.

PubMed

Clay, Alison S; Ross, Elizabeth; Chudgar, Saumil M; Grochowski, Colleen O'Connor; Tulsky, James A; Shapiro, Dan

2015-03-01

To determine the emotional responses to patient care activities described by fourth year medical students. Qualitative content analysis for emerging themes in letters written by graduating medical students to patients during a Capstone Course. The patient need not be alive and the letter would never be sent. Six themes emerged from student letters: (1) Sorrow for the depths of patient suffering; (2) Gratitude towards patients and their families; (3) Personal responsibility for care provided to patients; (4) Regret for poor care provided by the student or student's team; (5) Shattered expectations about medicine and training; and (6) Anger towards patients. Students expressed sensitivity to vulnerable patients, including those who were alone, unable to communicate, or for whom care was biased. Students' expressed powerlessness (inability to cure, managing a work-life balance, and challenges with hierarchy) in some essays. At graduation, medical students describe strong emotions about previous patient care experiences, including difficulty witnessing suffering, disappointment with medicine, and gratitude to patients and their families Providing regular opportunities for writing throughout medical education would allow students to recognize their emotions, reflect upon them and promote wellness that would benefit students and their patients. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Structure and characteristics of heterogeneous detonation

NASA Astrophysics Data System (ADS)

Nicholls, J. A.; Sichel, M.; Kauffman, C. W.

1983-09-01

The emphasis of this research program centered around the structure of heterogeneous detonation waves, inasmuch as this had been found to be very important to the detonation characteristics of heterogeneous mixtures. On the experimental side, a vertical detonation tube was used wherein liquid fuel drops, all of one size, were generated at the top of the tube and allowed to fall vertically into the desired gaseous mixture. A strong blast wave was transmitted into the mixture through use of an auxiliary shock tube. The propagation of the resultant wave was monitored by pressure switches, pressure transducers, and photography. The low vapor pressure liquid fuel, decane (400 micrometer drop size) was used for most of the experiments. Attention was given to wave structure, wave velocity, and initiation energy. Three atmospheres (100% O2; 40% O2/60% N2; and air) and a number of equivalence ratios were investigated. Holographic pictures and streak photography were employed to study the drop shattering process and the structure of the front. Other experiments investigated the addition of the sensitizer, normal propyl nitrate (NPN), to the decane. The important aspect of vapor pressure was studied by heating the entire tube to various elevated temperatures and then noting the effect on detonability.

Searching for and Finding Meaning in Collective Trauma: Results From a National Longitudinal Study of the 9/11 Terrorist Attacks

PubMed Central

Updegraff, John A.; Silver, Roxane Cohen; Holman, E. Alison

2008-01-01

The ability to make sense of events in one’s life has held a central role in theories of adaptation to adversity. However, there are few rigorous studies on the role of meaning in adjustment, and those that have been conducted have focused predominantly on direct personal trauma. The authors examined the predictors and long-term consequences of Americans’ searching for and finding meaning in a widespread cultural upheaval—the terrorist attacks of September 11, 2001—among a national probability sample of U.S. adults (N = 931). Searching for meaning at 2 months post-9/11 was predicted by demographics and high acute stress response. In contrast, finding meaning was predicted primarily by demographics and specific early coping strategies. Whereas searching for meaning predicted greater posttraumatic stress (PTS) symptoms across the following 2 years, finding meaning predicted lower PTS symptoms, even after controlling for pre-9/11 mental health, exposure to 9/11, and acute stress response. Mediation analyses suggest that finding meaning supported adjustment by reducing fears of future terrorism. Results highlight the role of meaning in adjustment following collective traumas that shatter people’s fundamental assumptions about security and invulnerability. PMID:18729704

Continuous and large sediment supply in a steep landslide scar, Southern Japanese Alps

NASA Astrophysics Data System (ADS)

Nishii, Ryoko; Imaizumi, Fumitoshi; Daimaru, Hiromu; Murakami, Wataru

2018-07-01

Continuous sediment supply in the Aka-kuzure landslide scar, in the tectonically active alpine Southern Japanese Alps, was investigated using airborne light detection and ranging data in 2000, 2003, 2007 and 2012. In addition, we focused on the spatial variability of denudation patterns based on topographical analyses using DEMs. Denudation volume for the past 12 years reached about 106 m3 and mean annual denudation rate ranged from 0.25 to 0.31 m/yr. Topographical analyses revealed that sediment supply in the scar consists of a combination of two denudation types, sporadic-deep and wide-thin. These denudation types have different roles in the topographical development of the landslide scar. Sporadic-deep type supplies less volume than wide-thin type but still contributes to channel development, as it mainly occurs on lower-order streams and tends to change the convex slope into a concave slope. In contrast, although denudation depth of the wide-thin type is thin, the area affected by this type extends to the whole landslide scar. Consequently, the wide-thin type accounts for most of the total volume lost, for which detachment by frost shattering is suggested as an important role.

Shattering the silence of violence against women.

PubMed

1998-01-01

The UN Development Fund for Women has selected 23 projects in 18 developing countries to be beneficiaries of a $1.2 million trust fund dedicated to the elimination of violence against women. While the projects offer a variety of approaches to preventing and eliminating the domestic violence suffered by a third of the women in developing countries, all involve awareness-raising and advocacy, capacity-building, literacy, training, action research, and prevention/deterrence activities. A project in the Philippines will train women migrant workers who have been victimized by abuse to produce videos about their experience in order to raise consciousness about the rights of women and of workers. A South African project, which will address sexual assaults of high school students that occur in dating relationships, will involve a prevalence survey, a pilot project, an expansion of the project and curriculum development, a play on date rape, crisis intervention counseling, production of a video and manual, a national conference, and publication of essays produced by students who participated in the program. The Trust Fund was proposed by Japan in response to the urgent call for action issued by the 1995 UN Fourth World Conference on Women and is funded by donations from governments and private sources.

Deep neural networks for texture classification-A theoretical analysis.

PubMed

Basu, Saikat; Mukhopadhyay, Supratik; Karki, Manohar; DiBiano, Robert; Ganguly, Sangram; Nemani, Ramakrishna; Gayaka, Shreekant

2018-01-01

We investigate the use of Deep Neural Networks for the classification of image datasets where texture features are important for generating class-conditional discriminative representations. To this end, we first derive the size of the feature space for some standard textural features extracted from the input dataset and then use the theory of Vapnik-Chervonenkis dimension to show that hand-crafted feature extraction creates low-dimensional representations which help in reducing the overall excess error rate. As a corollary to this analysis, we derive for the first time upper bounds on the VC dimension of Convolutional Neural Network as well as Dropout and Dropconnect networks and the relation between excess error rate of Dropout and Dropconnect networks. The concept of intrinsic dimension is used to validate the intuition that texture-based datasets are inherently higher dimensional as compared to handwritten digits or other object recognition datasets and hence more difficult to be shattered by neural networks. We then derive the mean distance from the centroid to the nearest and farthest sampling points in an n-dimensional manifold and show that the Relative Contrast of the sample data vanishes as dimensionality of the underlying vector space tends to infinity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Epigenetics, microbiota, and intraocular inflammation: New paradigms of immune regulation in the eye.

PubMed

Wen, Xiaofeng; Hu, Xiao; Miao, Li; Ge, Xiaofei; Deng, Yuhua; Bible, Paul W; Wei, Lai

2018-05-01

Sight threatening immune responses that damage the eye characterize intraocular inflammatory diseases. These diseases including uveitis and age-related macular degeneration are worryingly common and quality of life shattering. Genetic studies in past decades significantly advanced our understanding of the etiology of these devastating diseases. Unfortunately, patient genetics alone failed to adequately explain disease origin, susceptibility, and progression. Non-genetic factors such as the epigenetic regulation of ocular diseases and the environmental factors triggering intraocular inflammation offer new insight into intraocular inflammatory disorders. Importantly, mounting evidence is signaling that dysbiosis of human microbiota leads to rapid epigenomic reprograming of host cells and results in the onset of many diseases. In this review, we discuss how epigenetic mechanisms and microbiota may cooperate to initiate and perpetuate ocular inflammation. Lastly, we propose that the discovery of intraocular microbiota presents a significant shift in thought affecting current approaches to the diagnosis, treatment, and prevention of intraocular inflammatory diseases such as uveitis and age-related macular degeneration. The geographical and genetic background difference in both disease presentation and genetic association of intraocular inflammatory diseases may be due to the variation of intraocular microbiota. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Constitutional chromothripsis involving the critical region of 9q21.13 microdeletion syndrome.

PubMed

Genesio, Rita; Fontana, Paolo; Mormile, Angela; Casertano, Alberto; Falco, Mariateresa; Conti, Anna; Franzese, Adriana; Mozzillo, Enza; Nitsch, Lucio; Melis, Daniela

2015-01-01

The chromothripsis is a biological phenomenon, first observed in tumors and then rapidly described in congenital disorders. The principle of the chromothripsis process is the occurrence of a local shattering to pieces and rebuilding of chromosomes in a random order. Congenital chromothripsis rearrangements often involve reciprocal rearrangements on multiple chromosomes and have been described as cause of contiguous gene syndromes. We hypothesize that chromothripsis could be responsible for known 9q21.13 microdeletion syndrome, causing a composite phenotype with additional features. The case reported is a 16- years-old female with a complex genomic rearrangement of chromosome 9 including the critical region of 9q21.13 microdeletion syndrome. The patient presents with platelet disorder and thyroid dysfunction in addition to the classical neurobehavioral phenotype of the syndrome. The presence of multiple rearrangements on the same chromosome 9 and the rebuilding of chromosome in a random order suggested that the rearrangement could origin from an event of chromthripsis. To our knowledge this is the first report of congenital chromothripsis involving chromosome 9. Furthermore this is the only case of 9q21.13 microdeletion syndrome due to chromothripsis.

Microscopic Characterization of the Brazilian Giant Samba Virus.

PubMed

Schrad, Jason R; Young, Eric J; Abrahão, Jônatas S; Cortines, Juliana R; Parent, Kristin N

2017-02-14

Prior to the discovery of the mimivirus in 2003, viruses were thought to be physically small and genetically simple. Mimivirus, with its ~750-nm particle size and its ~1.2-Mbp genome, shattered these notions and changed what it meant to be a virus. Since this discovery, the isolation and characterization of giant viruses has exploded. One of the more recently discovered giant viruses, Samba virus, is a Mimivirus that was isolated from the Rio Negro in the Brazilian Amazon. Initial characterization of Samba has revealed some structural information, although the preparation techniques used are prone to the generation of structural artifacts. To generate more native-like structural information for Samba, we analyzed the virus through cryo-electron microscopy, cryo-electron tomography, scanning electron microscopy, and fluorescence microscopy. These microscopy techniques demonstrated that Samba particles have a capsid diameter of ~527 nm and a fiber length of ~155 nm, making Samba the largest Mimivirus yet characterized. We also compared Samba to a fiberless mimivirus variant. Samba particles, unlike those of mimivirus, do not appear to be rigid, and quasi-icosahedral, although the two viruses share many common features, including a multi-layered capsid and an asymmetric nucleocapsid, which may be common amongst the Mimiviruses .

Lunar and Planetary Science XXXV: Impacts: Modeling and Observations

NASA Technical Reports Server (NTRS)

2004-01-01

This document covers the following topics: Cratering on Titan: Projectiles, Craters and Impact Melt; The Cratering Database: Making Code Jockeys Honest; Popigai Impact Structure Modeling: Morphology and Worldwide Ejecta; Anhydrite EOS and Phase Diagram in Relation to Shock Decomposition; Computational Investigations of the Chesapeake Bay Impact Structure; Hydrocode Simulations of the Chesapeake Bay Impact; Lockne Crater as a Result of Oblique Impact; The Influence of a Deep Shelf Sea on the Excavation and Modification of a Marine-Target Crater, the Lockne Crater, Central Sweden; Pre-Drilling Investigation of the Lake Bosumtwi Impact Crater: Constraints from Geophysics and Numerical Modelling; Central Uplift Formation at the Middlesboro Impact Structure, Kentucky, USA; A SRTM Investigation of Serra da Cangalho Impact Structure, Brazil; Brazilian Impact Craters: A Review; Flynn Creek Impact Structure: New Insights from Breccias, Melt Features, Shatter Cones, and Remote Sensing; The Howell Structure, Lincoln County, Tennessee: A Review of Past and Current Research; After the Chicxulub Impact: Control on Depositional and Diagenetic History of the Cenozoic Carbonate Formations of the Northwestern Yucatan Peninsula, Mexico; Ni Contents by Non-Destructive In-Situ XRF Method of Takamatsu-Kagawa Crater District in Japan; and Akiyoshi Limestone Blocks Transported by the P/T Boundary Event to Japan Islands.

Developmental toxicity testing in the 21st century: the sword of Damocles shattered by embryonic stem cell assays?

PubMed

Seiler, Andrea; Oelgeschläger, Michael; Liebsch, Manfred; Pirow, Ralph; Riebeling, Christian; Tralau, Tewes; Luch, Andreas

2011-11-01

Modern society faces an inherent dilemma. In our globalized society, we are spoilt for choice by an ever-increasing number of products, many of which are made of new materials and compound mixtures. At the same time, as consumers we got accustomed to the idea of a life minimized for risk, including our own exposure to chemicals from the environment or to compounds present in and released from everyday products. Chemical safety testing bridges these obviously diverging interests, and the corresponding legislation has hence been tremendously extended (e.g., introduction of the European legislation REACH in 2007). However, the underlying regulatory toxicology still relies mainly on animal testing, which is relatively slow, expensive, and ethically arguable. Meanwhile, recent years have seen a surge in efforts to develop alternative testing systems and strategies. Expectations are particularly high for the applicability of stem cells as test systems especially for developmental toxicity testing in vitro. For the first time in history, test systems can be based on differentiating cells and tissue progenitors in culture, thus bringing the 'vision of toxicity testing in the 21st century' a step closer.

Are We on the Right Track: Can Our Understanding of Abscission in Model Systems Promote or Derail Making Improvements in Less Studied Crops?

PubMed Central

Patterson, Sara E.; Bolivar-Medina, Jenny L.; Falbel, Tanya G.; Hedtcke, Janet L.; Nevarez-McBride, Danielle; Maule, Andrew F.; Zalapa, Juan E.

2016-01-01

As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abscission process. Understanding this process can not only lead to genetic improvement, but also changes in cultural practices and management that will contribute to higher yields, improved quality and greater sustainability. As plant scientists, we have learned significant amounts about this process through the study of model plants such as Arabidopsis, tomato, rice, and maize. While these model systems have provided significant valuable information, we are sometimes challenged to use this knowledge effectively as variables including the economic value of the crop, the uniformity of the crop, ploidy levels, flowering and crossing mechanisms, ethylene responses, cultural requirements, responses to changes in environment, and cellular and tissue specific morphological differences can significantly influence outcomes. The value of genomic resources for lesser-studied crops such as cranberries and grapes and the orphan crop fonio will also be considered. PMID:26858730

Overview of Recent DIII-D Experimental Results

NASA Astrophysics Data System (ADS)

Fenstermacher, Max

2015-11-01

Recent DIII-D experiments have added to the ITER physics basis and to physics understanding for extrapolation to future devices. ELMs were suppressed by RMPs in He plasmas consistent with ITER non-nuclear phase conditions, and in steady state hybrid plasmas. Characteristics of the EHO during both standard high torque, and low torque enhanced pedestal QH-mode with edge broadband fluctuations were measured, including edge localized density fluctuations with a microwave imaging reflectometer. The path to Super H-mode was verified at high beta with a QH-mode edge, and in plasmas with ELMs triggered by Li granules. ITER acceptable TQ mitigation was obtained with low Ne fraction Shattered Pellet Injection. Divertor ne and Te data from Thomson Scattering confirm predicted drift-driven asymmetries in electron pressure, and X-divertor heat flux reduction and detachment were characterized. The crucial mechanisms for ExB shear control of turbulence were clarified. In collaboration with EAST, high beta-p scenarios were obtained with 80 % bootstrap fraction, high H-factor and stability limits, and large radius ITBs leading to low AE activity. Work supported by the US Department of Energy under DE-FC02-04ER54698 and DE-AC52-07NA27344.

About the history of sexuality.

PubMed

Shorter, Edward

2007-03-01

About 50 years of demolition work, it's time now for a return to the grand syntheses. Two of the great syntheses of the 19th century have now been shattered. Marxism lies in fragments. And psychoanalysis has largely drifted outside of psychiatry to find a new and doubtless temporary home in departments of literary studies. To be sure, the third of the great syntheses, Darwin's theory of evolution, remains intact. But otherwise, as far as the eye can see, there is rubble. The time for new attempts at synthesis is now nigh. After decades of pioneering work in the neurosciences, the fundamental importance of brain biology in the human condition has now become evident. Surely one of the new syntheses will draw upon neurochemistry and neurophysiology, and it is to the great credit of the Hungarian neurosciences that pharmacologist Joseph Knoll has now ventured a first attempt. This attempt will be widely discussed and will form the platform for other work that may end up building firm bridges between "neuroenhancers" and behavior - and, what's more, to show how this relationship has shaped the evolution of thousands of years of human destiny, a great synthesis indeed.

Energy transfer through a multi-layer liner for shaped charges

DOEpatents

Skolnick, Saul; Goodman, Albert

1985-01-01

This invention relates to the determination of parameters for selecting materials for use as liners in shaped charges to transfer the greatest amount of energy to the explosive jet. Multi-layer liners constructed of metal in shaped charges for oil well perforators or other applications are selected in accordance with the invention to maximize the penetrating effect of the explosive jet by reference to four parameters: (1) Adjusting the explosive charge to liner mass ratio to achieve a balance between the amount of explosive used in a shaped charge and the areal density of the liner material; (2) Adjusting the ductility of each layer of a multi-layer liner to enhance the formation of a longer energy jet; (3) Buffering the intermediate layers of a multi-layer liner by varying the properties of each layer, e.g., composition, thickness, ductility, acoustic impedance and areal density, to protect the final inside layer of high density material from shattering upon impact of the explosive force and, instead, flow smoothly into a jet; and (4) Adjusting the impedance of the layers in a liner to enhance the transmission and reduce the reflection of explosive energy across the interface between layers.

Are We on the Right Track: Can Our Understanding of Abscission in Model Systems Promote or Derail Making Improvements in Less Studied Crops?

PubMed

Patterson, Sara E; Bolivar-Medina, Jenny L; Falbel, Tanya G; Hedtcke, Janet L; Nevarez-McBride, Danielle; Maule, Andrew F; Zalapa, Juan E

2015-01-01

As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abscission process. Understanding this process can not only lead to genetic improvement, but also changes in cultural practices and management that will contribute to higher yields, improved quality and greater sustainability. As plant scientists, we have learned significant amounts about this process through the study of model plants such as Arabidopsis, tomato, rice, and maize. While these model systems have provided significant valuable information, we are sometimes challenged to use this knowledge effectively as variables including the economic value of the crop, the uniformity of the crop, ploidy levels, flowering and crossing mechanisms, ethylene responses, cultural requirements, responses to changes in environment, and cellular and tissue specific morphological differences can significantly influence outcomes. The value of genomic resources for lesser-studied crops such as cranberries and grapes and the orphan crop fonio will also be considered.

Sox and Drugs: Baseball, Steroids and Physics

NASA Astrophysics Data System (ADS)

Tobin, Roger

2008-03-01

The sports world is in an uproar over performance-enhancing drugs. In the United States steroids in baseball have received the most attention, in part because the purported effects are much more dramatic than in any other sport. From 1995-2003 a few players hit home runs at rates 20-50% higher than the best sluggers of the preceding century. Could steroids really increase home-run performance that much? I will describe a model that combines estimates of the physiological effects of steroids, known baseball physics, and reasonable models of batting effectiveness for highly skilled hitters. A 10% increase in muscle mass, which can reasonably be expected from steroid use, increases the speed of a batted ball by 3%. Because home runs are relatively rare events on the tail of a batter's range distribution, even this modest change in ball speed can increase the proportion of batted balls that result in home runs by 30 -- 70%, enough to account for the record-shattering performances of the recent past. I will also describe some of the attention -- both welcome and not -- that comes to the unsuspecting physicist who wades into such emotionally troubled waters.

Impact Delamination and Fracture in Aluminum/Acrylic Sandwich Plates

NASA Technical Reports Server (NTRS)

Liaw, Benjamin; Zeichner, Glenn; Liu, Yanxiong; Bowles, Kenneth J. (Technical Monitor)

2000-01-01

Impact-induced delamination and fracture in 6061-T6 aluminum/cast acrylic sandwich plates adhered by epoxy were generated in an instrumented drop-weight impact machine. Although only a small dent was produced on the aluminum side when a hemispherical penetrator tup was dropped onto it from a couple of inches, a large ring of delamination at the interface was observed. The delamination damage was often accompanied by severe shattering in the acrylic substratum. Damage patterns in the acrylic layer include radial and ring cracks and, together with delamination at the interface, may cause peeling-off of acrylic material from the sandwich plate. Theory of stress-wave propagation can be used to explain these damage patterns. The impact tests were conducted at various temperatures. The results also show clearly that temperature effect is very important in impact damage. For pure cast acrylic nil-ductile transition (NDT) occurs between 185-195 F. Excessive impact energy was dissipated into fracture energy when tested at temperature below this range or through plastic deformation when tested at temperature above the NDT temperature. Results from this study will be used as baseline data for studying fiber-metal laminates, such as GLARE and ARALL for advanced aeronautical and astronautical applications.

Integrating engineering principles into the medico-legal investigation of a rare fatal rollover car accident involving complex dynamics.

PubMed

Grassi, Vincenzo M; Castagnola, Flaminia; Miscusi, Massimo; De-Giorgio, Fabio

2016-09-01

Rollover car accidents can be the result of forceful steering or hitting an obstacle that acts like a ramp. Mortality from this type of car accident is particularly high, especially when occupants are thrown out of the vehicle. We report a case of a 67-year-old man who died after a rollover accident that occurred when he was driving a car equipped with a glass moonroof. He was found inside his car with his safety belt correctly fastened and the roof shattered. At autopsy, a wide avulsion injury of the head was observed, which was associated with an atlanto-axial dislocation and full-thickness fracture of the cervical body and posterior facet joints of the seventh cervical vertebra. The data collected at the scene of the accident were integrated with the autopsy results to yield a forensic engineering reconstruction. This reconstruction elucidated the dynamics of the event and correctly ascribed the lesions observed at autopsy to the phases of the rollover. Afterward, an analysis of the scientific literature concerning rollover crash tests was conducted to understand why the driver sustained fatal injuries even though his seatbelt was properly fastened.

Prescription safety eyewear: impact studies of lens and frame failure.

PubMed

Vinger, P F; Woods, T A

2000-02-01

To determine if a plano lens could be the test lens for all prescription (Rx) lenses and to investigate why Rx lenses pop out of safety eyewear. Plano and Rx polycarbonate lenses (n = 641) with varying thickness and edge geometry, mounted on steel lens holders, and Rx safety eyewear (n = 128) placed on headforms were impacted with test objects of varying diameter and hardness. Impacts were studied with 500 to 2,000 frames-per-second motion analysis. Plano lenses were at least, or more, prone to failure (dislodgment, perforation, shatter, or crack) than -3.00 or +3.00 lenses of the same minimum thickness. More than 40% of safety frames with removable lenses broke or had lenses pop out when impacted with energies expected in industry and sports. Plano lenses can be used as the test lenses for all Rx lenses made of the same material with the same minimal thickness. The ANSI Z87.1-1989 industrial standard for Rx eyewear is inadequate for sports or other activities with high-impact potential. The best lens-retention system has, as a component, a frame with a bevel perpendicular to a frontal impact force.

The origin and emergence of life under impact bombardment.

PubMed

Cockell, Charles S

2006-10-29

Craters formed by asteroids and comets offer a number of possibilities as sites for prebiotic chemistry, and they invite a literal application of Darwin's 'warm little pond'. Some of these attributes, such as prolonged circulation of heated water, are found in deep-ocean hydrothermal vent systems, previously proposed as sites for prebiotic chemistry. However, impact craters host important characteristics in a single location, which include the formation of diverse metal sulphides, clays and zeolites as secondary hydrothermal minerals (which can act as templates or catalysts for prebiotic syntheses), fracturing of rock during impact (creating a large surface area for reactions), the delivery of iron in the case of the impact of iron-containing meteorites (which might itself act as a substrate for prebiotic reactions), diverse impact energies resulting in different rates of hydrothermal cooling and thus organic syntheses, and the indiscriminate nature of impacts into every available lithology-generating large numbers of 'experiments' in the origin of life. Following the evolution of life, craters provide cryptoendolithic and chasmoendolithic habitats, particularly in non-sedimentary lithologies, where limited pore space would otherwise restrict colonization. In impact melt sheets, shattered, mixed rocks ultimately provided diverse geochemical gradients, which in present-day craters support the growth of microbial communities.

Microscopic Characterization of the Brazilian Giant Samba Virus

PubMed Central

Schrad, Jason R.; Young, Eric J.; Abrahão, Jônatas S.; Cortines, Juliana R.; Parent, Kristin N.

2017-01-01

Prior to the discovery of the mimivirus in 2003, viruses were thought to be physically small and genetically simple. Mimivirus, with its ~750-nm particle size and its ~1.2-Mbp genome, shattered these notions and changed what it meant to be a virus. Since this discovery, the isolation and characterization of giant viruses has exploded. One of the more recently discovered giant viruses, Samba virus, is a Mimivirus that was isolated from the Rio Negro in the Brazilian Amazon. Initial characterization of Samba has revealed some structural information, although the preparation techniques used are prone to the generation of structural artifacts. To generate more native-like structural information for Samba, we analyzed the virus through cryo-electron microscopy, cryo-electron tomography, scanning electron microscopy, and fluorescence microscopy. These microscopy techniques demonstrated that Samba particles have a capsid diameter of ~527 nm and a fiber length of ~155 nm, making Samba the largest Mimivirus yet characterized. We also compared Samba to a fiberless mimivirus variant. Samba particles, unlike those of mimivirus, do not appear to be rigid, and quasi-icosahedral, although the two viruses share many common features, including a multi-layered capsid and an asymmetric nucleocapsid, which may be common amongst the Mimiviruses. PMID:28216551

The changing face of hemostasis testing in modern laboratories: consolidation, automation, and beyond.

PubMed

Lippi, Giuseppe; Plebani, Mario; Favaloro, Emmanuel J

2015-04-01

The reality of laboratory diagnostics as a whole, and hemostasis testing in particular, is evolving under new paradigms of efficiency. The driving forces of health care and laboratory diagnostics in the third millennium are mainly represented by macro- and microeconomics. In a world with limited resources, shattered by an unprecedented economic crisis, laboratory diagnostics is undergoing a substantial reorganization, with emergence of new models under the imperative of terms, such as bedside testing, consolidation, and networking. The paradigms under which these changes are being developed include a variety of environment, preanalytical, technological, professional, and health-care aspects. The maintenance of continued quality is indeed the major challenge to be faced in the foreseeable future. In fact, some challenges prepotently emerge during a consolidation process, which basically involve delayed testing, centrifugation, transportation, and stability of the specimens, as well as the potential mismatch of sample matrix. This article is aimed to provide an overview of the current economic scenario of laboratory diagnostics and discuss the changing face of hemostasis testing in modern laboratories, providing a synthetic overview about potential drawbacks of actualized solutions. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Tertiary extension and mineral deposits, southwestern U.S.

USGS Publications Warehouse

Rehrig, William A.; Hardy, James.J.

1996-01-01

Starting in Las Vegas, we will traverse through many of the geometric elements and complexities of hanging wall deformation above the regional detachment systems of the Colorado River extensional terrane. We will study the interaction of normal faults as arranged in regional, crustal-scale mega-domains and the bounding structures that separate these tilt domains. As we progress through the classic Eldorado Mountains-Hoover Dam region, where many of the ideas of listric normal faulting were first popularized, we will see both the real rocks and the historic rationale for their deformation. By examining the listric versus domino models for normal faulting, we will utilize different geometric techniques for determining the depth to the detachment structures and percent extension. Continuing further south toward southernmost Nevada, we will cross the accommodation zone that separates the Lake Mead and Whipple dip domains and further descend to deeper structural levels to examine lower levels of the major normal faults and their tilting of upper-crustal blocks and associated offset along the regional detachment faults. Fluid flow within the shattered fault zones and its relationship to the 3-D geometries of the fault surfaces will be studied both along the faults and within the hydrothermally altered and mineralized wallrocks.

Effect of slurry composition on the chemical mechanical polishing of thin diamond films

PubMed Central

Werrell, Jessica M.; Mandal, Soumen; Thomas, Evan L. H.; Brousseau, Emmanuel B.; Lewis, Ryan; Borri, Paola; Davies, Philip R.; Williams, Oliver A.

2017-01-01

Nanocrystalline diamond (NCD) thin films grown by chemical vapour deposition have an intrinsic surface roughness, which hinders the development and performance of the films’ various applications. Traditional methods of diamond polishing are not effective on NCD thin films. Films either shatter due to the combination of wafer bow and high mechanical pressures or produce uneven surfaces, which has led to the adaptation of the chemical mechanical polishing (CMP) technique for NCD films. This process is poorly understood and in need of optimisation. To compare the effect of slurry composition and pH upon polishing rates, a series of NCD thin films have been polished for three hours using a Logitech Ltd. Tribo CMP System in conjunction with a polyester/polyurethane polishing cloth and six different slurries. The reduction in surface roughness was measured hourly using an atomic force microscope. The final surface chemistry was examined using X-ray photoelectron spectroscopy and a scanning electron microscope. It was found that of all the various properties of the slurries, including pH and composition, the particle size was the determining factor for the polishing rate. The smaller particles polishing at a greater rate than the larger ones. PMID:29057022

A real-time standard parts inspection based on deep learning

NASA Astrophysics Data System (ADS)

Xu, Kuan; Li, XuDong; Jiang, Hongzhi; Zhao, Huijie

2017-10-01

Since standard parts are necessary components in mechanical structure like bogie and connector. These mechanical structures will be shattered or loosen if standard parts are lost. So real-time standard parts inspection systems are essential to guarantee their safety. Researchers would like to take inspection systems based on deep learning because it works well in image with complex backgrounds which is common in standard parts inspection situation. A typical inspection detection system contains two basic components: feature extractors and object classifiers. For the object classifier, Region Proposal Network (RPN) is one of the most essential architectures in most state-of-art object detection systems. However, in the basic RPN architecture, the proposals of Region of Interest (ROI) have fixed sizes (9 anchors for each pixel), they are effective but they waste much computing resources and time. In standard parts detection situations, standard parts have given size, thus we can manually choose sizes of anchors based on the ground-truths through machine learning. The experiments prove that we could use 2 anchors to achieve almost the same accuracy and recall rate. Basically, our standard parts detection system could reach 15fps on NVIDIA GTX1080 (GPU), while achieving detection accuracy 90.01% mAP.

Proteomics in food: Quality, safety, microbes, and allergens.

PubMed

Piras, Cristian; Roncada, Paola; Rodrigues, Pedro M; Bonizzi, Luigi; Soggiu, Alessio

2016-03-01

Food safety and quality and their associated risks pose a major concern worldwide regarding not only the relative economical losses but also the potential danger to consumer's health. Customer's confidence in the integrity of the food supply could be hampered by inappropriate food safety measures. A lack of measures and reliable assays to evaluate and maintain a good control of food characteristics may affect the food industry economy and shatter consumer confidence. It is imperative to create and to establish fast and reliable analytical methods that allow a good and rapid analysis of food products during the whole food chain. Proteomics can represent a powerful tool to address this issue, due to its proven excellent quantitative and qualitative drawbacks in protein analysis. This review illustrates the applications of proteomics in the past few years in food science focusing on food of animal origin with some brief hints on other types. Aim of this review is to highlight the importance of this science as a valuable tool to assess food quality and safety. Emphasis is also posed in food processing, allergies, and possible contaminants like bacteria, fungi, and other pathogens. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tales of biographical disintegration: how parents make sense of their sons' suicides.

PubMed

Owens, Christabel; Lambert, Helen; Lloyd, Keith; Donovan, Jenny

2008-03-01

Suicide research relies heavily on accounts provided by bereaved relatives, using a method known as the psychological autopsy. Psychological autopsy studies are invariably quantitative in design and their findings reinforce the medical model of suicide, emphasising the role of mental illness. They largely ignore the meanings that narrators attach to events, the nature of the sense-making task and the influences bearing upon it. This study drew on psychological autopsy data but used qualitative analytic methods. Fourteen semi-structured interviews with the parents of young men aged 18-30 who had taken their own lives form the basis for this paper. Some parents represent their sons as victims who were cruelly destroyed by external forces, while others portray them as agents of their own destruction. Either way, their narratives are dominated by moral rather than medical categories and by questions of personal accountability. We show how the parents use the interview to perform a complex reconstructive task, striving to piece together both their son's and their own shattered biographies and repair damage to their moral identities. We argue that their stories represent survival tools, enabling them not only to make sense of the past but also to face their own future.

Effect of slurry composition on the chemical mechanical polishing of thin diamond films

NASA Astrophysics Data System (ADS)

Werrell, Jessica M.; Mandal, Soumen; Thomas, Evan L. H.; Brousseau, Emmanuel B.; Lewis, Ryan; Borri, Paola; Davies, Philip R.; Williams, Oliver A.

2017-12-01

Nanocrystalline diamond (NCD) thin films grown by chemical vapour deposition have an intrinsic surface roughness, which hinders the development and performance of the films' various applications. Traditional methods of diamond polishing are not effective on NCD thin films. Films either shatter due to the combination of wafer bow and high mechanical pressures or produce uneven surfaces, which has led to the adaptation of the chemical mechanical polishing (CMP) technique for NCD films. This process is poorly understood and in need of optimisation. To compare the effect of slurry composition and pH upon polishing rates, a series of NCD thin films have been polished for three hours using a Logitech Ltd. Tribo CMP System in conjunction with a polyester/polyurethane polishing cloth and six different slurries. The reduction in surface roughness was measured hourly using an atomic force microscope. The final surface chemistry was examined using X-ray photoelectron spectroscopy and a scanning electron microscope. It was found that of all the various properties of the slurries, including pH and composition, the particle size was the determining factor for the polishing rate. The smaller particles polishing at a greater rate than the larger ones.

Understanding Effective Diameter and Its Application to Terrestrial Radiation in Ice Clouds

NASA Technical Reports Server (NTRS)

Mitchell, D. L.; Lawson, R. P.; Baker, B.

2011-01-01

The cloud property known as "effective diameter" or "effective radius", which in essence is the cloud particle size distribution (PSD) volume at bulk density divided by its projected area, is used extensively in atmospheric radiation transfer, climate modeling and remote sensing. This derives from the assumption that PSD optical properties can be uniquely described in terms of their effective diameter, D(sub e), and their cloud water content (CWC), henceforth referred to as the D(sub e)-CWC assumption. This study challenges this assumption, showing that while the D(sub e)-CWC assumption appears generally valid for liquid water clouds, it appears less valid for ice clouds in regions where (1) absorption is not primarily a function of either the PSD ice water content (IWC) or the PSD projected area, and (2) where wave resonance (i.e. photon tunneling) contributes significantly to absorption. These two regions often strongly coincide at terrestrial wavelengths when De less than 60 m, which is where this D(sub e)-CWC assumption appears poorest. Treating optical properties solely in terms of D(sub e) and IWC may lead to errors up to 24%, 26% and 20% for terrestrial radiation in the window region regarding the absorption and extinction coefficients and the single scattering albedo, respectively. Outside the window region, errors may reach 33% and 42% regarding absorption and extinction. The magnitude and sign of these errors can change rapidly with wavelength, which may produce significant errors in climate modeling, remote sensing and other applications concerned with the wavelength dependence of radiation. Where the D(sub e)-CWC assumption breaks down, ice cloud optical properties appear to depend on D(sub e), IWC and the PSD shape. Optical property parameterizations in climate models and remote sensing algorithms based on historical PSD measurements may exhibit errors due to previously unknown PSD errors (i.e. the presence of ice artifacts due to the shattering of larger ice particles on the probe inlet tube during sampling). More recently developed cloud probes are designed to mitigate this shattering problem. Using realistic PSD shapes for a given temperature (and/or IWC) and cloud type may minimize errors associated with PSD shape in ice optics parameterizations and remote sensing algorithms. While this topic was investigated using two ice optics schemes (the Yang et al., 2005 database and the modified anomalous diffraction approximation, or MADA), a physical understanding of the limitations of the D(sub e)-IWC assumption was made possible by using MADA. MADA allows one to approximate the contribution of photon tunneling to absorption relative to other optical processes, which reveals that part of the error regarding the D(sub e)-IWC assumption can be associated with tunneling. By relating the remaining error to the radiation penetration depth in bulk ice (DELTA L) due to absorption, the domain where the D(sub e)-IWC assumption is weakest was described in terms of D(sub e) and DELTA L.

Using earthquake-triggered landslides as a hillslope-scale shear strength test: Insights into rock strength properties at geomorphically relevant spatial scales in high-relief, tectonically active settings

NASA Astrophysics Data System (ADS)

Gallen, Sean; Clark, Marin; Godt, Jonathan; Lowe, Katherine

2016-04-01

The material strength of rock is known to be a fundamental property in setting landscape form and geomorphic process rates as it acts to modulate feedbacks between earth surface processes, tectonics, and climate. Despite the long recognition of its importance in landscape evolution, a quantitative understanding of the role of rock strength in affecting geomorphic processes lags our knowledge of the influence of tectonics and climate. This gap stems largely from the fact that it remains challenging to quantify rock strength at the hillslope scale. Rock strength is strongly scale dependent because the number, size, spacing, and aperture of fractures sets the upper limit on rock strength, making it difficult to extrapolate laboratory measurements to landscape-scale interpretations. Here we present a method to determine near-surface rock strength at the hillslope-scale, relying on earthquake-triggered landslides as a regional-scale "shear strength" test. We define near-surface strength as the average strength of rock sample by the landslides, which is typically < 10 m. Based on a Newmark sliding block model, which approximates slope stability during an earthquake assuming a material with frictional and cohesive strength, we developed a coseismic landslide model that is capable of reproducing statistical characteristics of the distribution of earthquake-triggered landslides. We present results from two well-documented case-studies of earthquakes that caused widespread mass-wasting; the 2008 Mw 7.9 Wenchuan Earthquake, Sichuan Province, China and the 1994 Mw. 6.8 Northridge Earthquake, CA, USA. We show how this model can be used to determine near-surface rock strength and reproduce mapped landslide patterns provided the spatial distribution of local hillslope gradient, earthquake peak ground acceleration (PGA), and coseismic landsliding are well constrained. Results suggest that near-surface rock strength in these tectonically active settings is much lower than that obtained using typical laboratory shear strength measurements on intact rock samples. Furthermore, the near-surface material strength is similar between the study areas despite differences in tectonic, climatic, and lithologic conditions. Variations in near-surface strength within each setting appear to be more strongly associated with factors contributing to the weakening rock through chemical or physical weathering, such as mean annual precipitation and distance to active faults (a proxy for rock shattering intensity), rather than intrinsic lithologic properties. We hypothesize that the shattering of rock through long-term permanent strain accumulation and by repeated earthquakes is an important mechanism that can explain low rock strength values among the different study sites and the spatial pattern of rock strength within each location. These findings emphasize the potential role of factors other than lithology in controlling the spatial distribution of near-surface rock strength in high-relief, tectonically active settings, which has important implications for understanding the evolution of landscapes, interpreting tectonic and climatic signals from topography, critical zone processes, and natural hazard assessment.

Understanding effective diameter and its application to terrestrial radiation in ice clouds

NASA Astrophysics Data System (ADS)

Mitchell, D. L.; Lawson, R. P.; Baker, B.

2010-12-01

The cloud property known as "effective diameter" or "effective radius", which in essence is the cloud particle size distribution (PSD) volume at bulk density divided by its projected area, is used extensively in atmospheric radiation transfer, climate modeling and remote sensing. This derives from the assumption that PSD optical properties can be uniquely described in terms of their effective diameter, De, and their cloud water content (CWC), henceforth referred to as the De-CWC assumption. This study challenges this assumption, showing that while the De-CWC assumption appears generally valid for liquid water clouds, it appears less valid for ice clouds in regions where (1) absorption is not primarily a function of either the PSD ice water content (IWC) or the PSD projected area, and (2) where wave resonance (i.e. photon tunneling) contributes significantly to absorption. These two regions often strongly coincide at terrestrial wavelengths when De<∼60 μm, which is where this De-CWC assumption appears poorest. Treating optical properties solely in terms of De and IWC may lead to errors up to 24%, 26% and 20% for terrestrial radiation in the window region regarding the absorption and extinction coefficients and the single scattering albedo, respectively. Outside the window region, errors may reach 33% and 42% regarding absorption and extinction. The magnitude and sign of these errors can change rapidly with wavelength, which may produce significant errors in climate modeling, remote sensing and other applications concerned with the wavelength dependence of radiation. Where the De-CWC assumption breaks down, ice cloud optical properties appear to depend on De, IWC and the PSD shape. Optical property parameterizations in climate models and remote sensing algorithms based on historical PSD measurements may exhibit errors due to previously unknown PSD errors (i.e. the presence of ice artifacts due to the shattering of larger ice particles on the probe inlet tube during sampling). More recently developed cloud probes are designed to mitigate this shattering problem. Using realistic PSD shapes for a given temperature (and/or IWC) and cloud type may minimize errors associated with PSD shape in ice optics parameterizations and remote sensing algorithms. While this topic was investigated using two ice optics schemes (the Yang et al. (2005) database and the modified anomalous diffraction approximation, or MADA), a physical understanding of the limitations of the De-IWC assumption was made possible by using MADA. MADA allows one to separate the photon tunneling process from the other optical processes, which reveals that much of the error regarding the De-IWC assumption can be associated with tunneling. By relating the remaining error to the radiation penetration depth in bulk ice (ΔL) due to absorption, the domain where the De-IWC assumption is weakest was described in terms of De and ΔL.

Application of rape pod sealants to reduce adverse environmental impacts.

PubMed

Bauša, Laimis; Steponavičius, Dainius; Jotautienė, Eglė; Kemzūraitė, Aurelija; Zaleckas, Ernestas

2018-04-01

Rape (Brassica napus L.) is a major global oilseed crop characterized by its high potential as an alimentary oil and in biodiesel production. The two most popular pod sealants (PS) used to reduce rape pod shattering are products in the pinolene range (di-1-p-menthene) and latex polymer products. Reports on the effective preservation of seed yield by these products are fairly contradictory. With this in mind, an experimental PS (PS4) that contained the active agents acrylic and trisiloxane was developed. Comparative experimental trials of the developed PS4 and three other PS (PS1, PS2 and PS3) containing active agents that are generally used for sealant production were conducted. The studies showed that the static and dynamic surface tension of PS4 was the lowest at the same concentration (2.0 g kg -1 ), consequently demonstrating the lowest spray drift. The chemical substances from PS had not penetrated the rape seeds in any of the PSs. The results indicate that treatment with PS4 exerts a beneficial effect in reducing rape seed yield loss (68-104 kg ha -1 in 2014 and 194-305 kg ha -1 in 2015) compared to other investigated PS. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

A new cryogenic diode thermometer

NASA Astrophysics Data System (ADS)

Courts, S. S.; Swinehart, P. R.; Yeager, C. J.

2002-05-01

While the introduction of yet another cryogenic diode thermometer is not earth shattering, a new diode thermometer, the DT-600 series, recently introduced by Lake Shore Cryotronics, possesses three features that make it unique among commercial diode thermometers. First, these diodes have been probed at the chip level, allowing for the availability of a bare chip thermometer matching a standard curve-an important feature in situations where real estate is at a premium (IR detectors), or where in-situ calibration is difficult. Second, the thermometry industry has assumed that interchangeability should be best at low temperatures. Thus, good interchangeability at room temperatures implies a very good interchangeability at cryogenic temperature, resulting in a premium priced sensor. The DT-600 series diode thermometer is available in an interchangeability band comparable to platinum RTDs with the added advantage of interchangeability to 2 K. Third, and most important, the DT-600 series diode does not exhibit an instability in the I-V characteristic in the 8 K to 20 K temperature range that is observed in other commercial diode thermometer devices [1]. This paper presents performance characteristics for the DT-600 series diode thermometer along with a comparison of I-V curves for this device and other commercial diode thermometers exhibiting an I-V instability.

Upheaval Dome, An Analogue Site for Gale Center

NASA Technical Reports Server (NTRS)

Conrad, P. G.; Eignebrode, J. L.

2011-01-01

We propose Upheaval Dome in southeastern Utah as an impact analogue site on Earth to Mars Science Laboratory candidate landing site Gale Crater. The genesis of Upheaval Dome was a mystery for some time--originally thought to be a salt dome. The 5 km crater was discovered to possess shocked quartz and other shock metamorphic features just a few years ago, compelling evidence that the crater was formed by impact, although the structural geology caused Shoemaker and Herkenhoff to speculate an impact origin some 25 years earlier. The lithology of the crater is sedimentary. The oldest rocks are exposed in the center of the dome, upper Permian sandstones, and progressively younger units are well exposed moving outward from the center. These are Triassic sandstones, siltstones and shales, which are intruded by clastic dikes. There are also other clay-rich strata down section, as is the case with Gale Crater. There is significant deformation in the center of the crater, with folding and steeply tilted beds, unlike the surrounding Canyonlands area, which is relatively undeformed. The rock units are well exposed at Upheaval Dome, and there are shatter cones, impactite fragments, shocked quartz grains and melt rocks present. The mineral shock features suggest that the grains were subjected to dynamic pressures> 10 GPa.

When the world collapses: changed worldview and social reconstruction in a traumatized community

PubMed Central

Biruski, Dinka Corkalo; Ajdukovic, Dean; Stanic, Ajana Löw

2014-01-01

Background Traumatic experience can affect the individual's basic beliefs about the world as a predictable and safe place. One of the cornerstones in recovery from trauma is reestablishment of safety, connectedness, and the shattered schema of a worldview. Objective This study explored the role of negatively changed worldview in the relationship between war-related traumatization and readiness for social reconstruction of intergroup relations in a post-conflict community measured by three processes: intergroup rapprochement, rebuilding trust, and need for apology. It was hypothesized that more traumatized people are less supportive of social reconstruction and that this relationship is mediated by the changed worldview. Method The study included a community random sample of 333 adults in the city of Vukovar, Croatia, that was most devastated during the 1991–1995 war. Six instruments were administered: Stressful Events Scale, Impact of Event Scale-Revised, Changed Worldview Scale, and three scales measuring the post-conflict social reconstruction processes: Intergroup Rapprochement, Intergroup Trust and Need for Apology. Results Mediation analyses showed that the worldview change fully mediated between traumatization and all three aspects of social reconstruction. Conclusions In a population exposed to war traumatization the worldview change mediates post-conflict social recovery of community relations. PMID:25279101

The geometry of slip surfaces in the hanging-wall of the Sierra Madre fault, La-Canada, California

NASA Astrophysics Data System (ADS)

Dor, O.; Sammis, C. G.; Ben-Zion, Y.

2009-12-01

Fault-slip data from the granitic hanging-wall of the Sierra Madre fault near La-Canada, California, show a steeply dipping conjugate set of cm- to decimeter scale slip surfaces (115 data samples) with moderate to strong inclinations of slip vectors. These off-fault damage elements may be associated with Mohr-Coulomb slip in the stress field of a propagating earthquake rupture. At the microscale, we identified two dominant fracture orientations. The first appears both near and far from the fault and is compatible with Andersonian failure on the main fault. The second appears only within meters from the fault and may be associated with the formation of the slip surfaces. Characterization of damage fabric in the microscale suggests that in-situ failure of grains under tension with minimal strain immediately above the fault plane may be associated with an opening mode of rupture. We conclude that the architecture of the slip surfaces was developed during slip events over a finite displacement history with fairly stable faulting conditions, and that with continuing displacement, as the rock mass approached the surface, a dynamic opening mode could have led to the shattering of grains in the immediate vicinity of the slip zone.

Formation of semisolid, oligomerized aqueous SOA: lab simulations of cloud processing.

PubMed

Hawkins, Lelia N; Baril, Molly J; Sedehi, Nahzaneen; Galloway, Melissa M; De Haan, David O; Schill, Gregory P; Tolbert, Margaret A

2014-02-18

Glyoxal, methylglyoxal, glycolaldehyde, and hydroxyacetone form N-containing and oligomeric compounds during simulated cloud processing with small amines. Using a novel hygroscopicity tandem differential mobility analysis (HTDMA) system that allows varied humidification times, the hygroscopic growth (HG) of each of the resulting products of simulated cloud processing was measured. Continuous water uptake (gradual deliquescence) was observed beginning at ∼ 40% RH for all aldehyde-methylamine products. Particles containing ionic reaction products of either glyoxal or glycine were most hygroscopic, with HG between 1.16 and 1.20 at 80% RH. Longer humidification times (up to 20 min) produced an increase in growth factors for glyoxal-methylamine (19% by vol) and methylglyoxal-methylamine (8% by vol) aerosol, indicating that unusually long equilibration times can be required for HTDMA measurements of such particles. Glyoxal- and methylglyoxal-methylamine aerosol particles shattered in Raman microscopy impact-flow experiments, revealing that the particles were semisolid. Similar experiments on glycolaldehyde- and hydroxyacetone-methylamine aerosol found that the aerosol particles were liquid when dried for <1 h, but semisolid when dried for 20 h under ambient conditions. The RH required for flow (liquification) during humidification experiments followed the order methylglyoxal > glyoxal > glycolaldehyde = hydroxyacetone, likely caused by the speed of oligomer formation in each system.

Cryogenic lifetime tests on a commercial epoxy resin high voltage bushing

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

Schwenterly, S W; Pleva, Ed; Ha, Tam T

2012-06-12

High-temperature superconducting (HTS) power devices operating in liquid nitrogen frequently require high-voltage bushings to carry the current leads from the superconducting windings to the room temperature grid connections. Oak Ridge National Laboratory is collaborating with Waukesha Electric Systems, SuperPower, and Southern California Edison to develop and demonstrate an HTS utility power transformer. Previous dielectric high voltage tests in support of this program have been carried out in test cryostats with commercial epoxy resin bushings from Electro Composites Inc. (ECI). Though the bushings performed well in these short-term tests, their long-term operation at high voltage in liquid nitrogen needs to bemore » verified for use on the utility grid. Long-term tests are being carried out on a sample 28-kV-class ECI bushing. The bushing has a monolithic cast, cycloaliphatic resin body and is fire- and shatter-resistant. The test cryostat is located in an interlocked cage and is energized at 25 kVac around the clock. Liquid nitrogen (LN) is automatically refilled every 9.5 hours. Partial discharge, capacitance, and leakage resistance tests are periodically performed to check for deviations from factory values. At present, over 2400 hours have been accumulated with no changes in these parameters. The tests are scheduled to run for four to six months.« less

The origin and emergence of life under impact bombardment

PubMed Central

Cockell, Charles S

2006-01-01

Craters formed by asteroids and comets offer a number of possibilities as sites for prebiotic chemistry, and they invite a literal application of Darwin's ‘warm little pond’. Some of these attributes, such as prolonged circulation of heated water, are found in deep-ocean hydrothermal vent systems, previously proposed as sites for prebiotic chemistry. However, impact craters host important characteristics in a single location, which include the formation of diverse metal sulphides, clays and zeolites as secondary hydrothermal minerals (which can act as templates or catalysts for prebiotic syntheses), fracturing of rock during impact (creating a large surface area for reactions), the delivery of iron in the case of the impact of iron-containing meteorites (which might itself act as a substrate for prebiotic reactions), diverse impact energies resulting in different rates of hydrothermal cooling and thus organic syntheses, and the indiscriminate nature of impacts into every available lithology—generating large numbers of ‘experiments’ in the origin of life. Following the evolution of life, craters provide cryptoendolithic and chasmoendolithic habitats, particularly in non-sedimentary lithologies, where limited pore space would otherwise restrict colonization. In impact melt sheets, shattered, mixed rocks ultimately provided diverse geochemical gradients, which in present-day craters support the growth of microbial communities. PMID:17008223

Trait impulsivity and change in mental health problems after violent crime victimization: a prospective analysis of the dutch longitudinal internet studies for the social sciences database.

PubMed

Kunst, Maarten; Van Wilsem, Johan

2013-05-01

Violent crime victimization can have serious mental health consequences, but what it is that makes victims at risk of mental health problems or delayed recovery from such problems is largely unknown. Previous research has focused on, amongst other things, the disabling impact of personality factors involved in the regulation of emotions. Using data from the Dutch Longitudinal Internet Studies for the Social Sciences (LISS) panel (n = 2628), this study explored whether the association between violent crime victimization and change in mental health problems over a 1-year time span also varies by trait impulsivity (TI)--a personality factor involved in regulating behavior. TI may serve as a risk factor for mental health problems, but research into this topic is scarce and inconsistent. Results suggested that low TI subjects are prone to experience an increase in mental health problems following victimization. As a possible explanation for this finding, it was speculated that subjects with low TI do not perceive themselves at risk of victimization and thus see this positive assumption shattered when victimization does occur. Results were further discussed in terms of study limitations and strengths and implications for future research.

Human dignity in religion-embedded cross-cultural nursing.

PubMed

Cheraghi, Mohammad A; Manookian, Arpi; Nasrabadi, Alireza N

2014-12-01

Although human dignity is an unconditional value of every human being, it can be shattered by extrinsic factors. It is necessary to discover the authentic meaning of patients' dignity preservation from different religious perspectives to provide professional cross-cultural care in a diverse setting. This article identifies common experiences of Iranian Muslim and Armenian Christian patients regarding dignified care at the bedside. This is a qualitative study of participants' experiences of dignified care elicited by individual in-depth semi-structured interviews. A purposeful sample of 10 participants (five Iranian Muslims and five Iranian Armenians) from various private and governmental hospital settings was chosen. This study was approved by the ethics committee of Tehran University of Medical Sciences. All the participants were provided with information about the purpose and the nature of the study, the voluntary condition of their participation in this study, and the anonymous reporting of recorded interviews. The common experiences of Christian and Muslim patients regarding dignity preservation emerged as "exigency of respecting human nobility" and "providing person-centered care." It is essential to recognize the humanness and individuality of each patient to preserve and promote human dignity in diverse cross-cultural settings. The findings support and expand current understanding about the objective and subjective nature of dignity preservation in cross-cultural nursing. © The Author(s) 2014.

Global health interdependence and the international physicians' movement.

PubMed

Gellert, G A

1990-08-01

International Physicians for the Prevention of Nuclear War has had an impressive public impact in the 1980s, helping to shatter the myths of surviving and medically responding to a nuclear attack. The 1990s present a new challenge for the medical community in a different social and international context characterized by increasing global interdependence. Another view of physician activism is presented to complement advocacy for nuclear disarmament in the promotion of peace. A framework for analysis is provided by "fateful visions"--accepted policy views of prospective superpower relations--drawn from practitioners of foreign policy, international relations, and security affairs. A perceptual gap may exist between physicians who wish to address underlying ethical and public health concerns on security issues and policy practitioners who are accustomed to discussion within existing policy frames of reference that can be pragmatically used. A strategy is proposed for physicians to use their specialized training and skills to evaluate trends in global health interdependence. The international physicians' movement may contribute substantively to the formulation of policy by expanding and interpreting an increasingly complex database on interdependence, and by creating a dialogue with policy formulators based on mutual recognition of the value and legitimacy of each professions' expertise and complementary contributions to international security policy.

HINCOF-1: a Code for Hail Ingestion in Engine Inlets

NASA Technical Reports Server (NTRS)

Gopalaswamy, N.; Murthy, S. N. B.

1995-01-01

One of the major concerns during hail ingestion into an engine is the resulting amount and space- and time-wise distribution of hail at the engine face for a given geometry of inlet and set of atmospheric and flight conditions. The appearance of hail in the capture streamtube is invariably random in space and time, with respect to size and momentum. During the motion of a hailstone through an inlet, a hailstone undergoes several processes, namely impact with other hailstones and material surfaces of the inlet and spinner, rolling and rebound following impact; heat and mass transfer; phase change; and shattering, the latter three due to friction and impact. Taking all of these factors into account, a numerical code, designated HINCOF-I, has been developed for determining the motion hailstones from the atmosphere, through an inlet, and up to the engine face. The numerical procedure is based on the Monte-Carlo method. The report presents a description of the code, along with several illustrative cases. The code can be utilized to relate the spinner geometry - conical or, more effective, elliptical - to the possible diversion of hail at the engine face into the bypass stream. The code is also useful for assessing the influence of various hail characteristics on the ingestion and distribution of hailstones over the engine face.

Exploring perceptions and preferences of patients, families, physicians, and nurses regarding cancer disclosure: a descriptive qualitative study.

PubMed

Abazari, Parvaneh; Taleghani, Fariba; Hematti, Simin; Ehsani, Maryam

2016-11-01

The aim of this study was to explore perceptions and preferences of cancer patients, their families, physicians, and nurses in disclosing cancer diagnosis. We selected 35 participants (15 patients, 6 family members, 9 physicians, and 5 nurses) by purposive sampling. We collected data by in-depth interviews and used qualitative content analysis for analysis. Data analysis resulted in three categories: (1) establishing a basis for breaking bad news; (2) adjusting to the tragedy of bad news; and (3) helping the patient cope with the shattering news. The first category comprised the following subcategories: provision of proper background; adhering to a patient-centered approach; and being unhurried. The second category comprised the following subcategories: cancer as a cultural taboo; death as a frightening vision of unattainable dreams and punishment; hope as an opening in the utter darkness of disease; and empathy as liniment for the injuries of disease. The third category comprised the following subcategories: the family as the most powerful healing source for the patient; the force of spirituality in achieving peace; and a multiprofessional, harmonious physician-centered team. The findings of this study can help healthcare teams break the bad news of cancer diagnosis in a more effective, satisfactory, and culture-based manner for patients and their families.

SPH/N-body simulations of small (D = 10 km) monolithic asteroidal breakups and improved parametric relations for Monte-Carlo collisional models

NASA Astrophysics Data System (ADS)

Ševecek, Pavel; Broz, Miroslav; Nesvorny, David; Durda, Daniel D.; Asphaug, Erik; Walsh, Kevin J.; Richardson, Derek C.

2016-10-01

Detailed models of asteroid collisions can yield important constrains for the evolution of the Main Asteroid Belt, but the respective parameter space is large and often unexplored. We thus performed a new set of simulations of asteroidal breakups, i.e. fragmentations of intact targets, subsequent gravitational reaccumulation and formation of small asteroid families, focusing on parent bodies with diameters D = 10 km.Simulations were performed with a smoothed-particle hydrodynamics (SPH) code (Benz & Asphaug 1994), combined with an efficient N-body integrator (Richardson et al. 2000). We assumed a number of projectile sizes, impact velocities and impact angles. The rheology used in the physical model does not include friction nor crushing; this allows for a direct comparison to results of Durda et al. (2007). Resulting size-frequency distributions are significantly different from scaled-down simulations with D = 100 km monolithic targets, although they may be even more different for pre-shattered targets.We derive new parametric relations describing fragment distributions, suitable for Monte-Carlo collisional models. We also characterize velocity fields and angular distributions of fragments, which can be used as initial conditions in N-body simulations of small asteroid families. Finally, we discuss various uncertainties related to SPH simulations.

Characteristics of terrestrial basaltic rock populations: Implications for Mars lander and rover science and safety

NASA Astrophysics Data System (ADS)

Craddock, Robert A.; Golombek, Matthew P.

2016-08-01

We analyzed the morphometry of basaltic rock populations that have been emplaced or affected by a variety of geologic processes, including explosive volcanic eruptions (as a proxy for impact cratering), catastrophic flooding, frost shattering, salt weathering, alluvial deposition, and chemical weathering. Morphometric indices for these rock populations were compared to an unmodified population of rocks that had broken off a solidified lava flow to understand how different geologic processes change rock shape. We found that a majority of rocks have an sphericity described as either a disc or sphere in the Zingg classification system and posit that this is a function of cooling fractures in the basalt (Zingg [1935] Schweiz. Miner. Petrogr. Mitt., 15, 39-140). Angularity (roundness) is the most diagnostic morphometric index, but the Corey Shape Factor (CSF), Oblate-Prolate Index (OPI) and deviation from compactness (D) also sometimes distinguished weathering processes. Comparison of our results to prior analyses of rock populations found at the Mars Pathfinder, Spirit, and Curiosity landing sites support previous conclusions. The observation that the size-frequency distribution of terrestrial rock populations follow exponential functions similar to lander and orbital measurements of rocks on Mars, which is expected from fracture and fragmentation theory, indicates that these distributions are being dominantly controlled by the initial fracture and fragmentation of the basalt.

Remote sensing evidence of lava-ground ice interactions associated with the Lost Jim Lava Flow, Seward Peninsula, Alaska

NASA Astrophysics Data System (ADS)

Marcucci, Emma C.; Hamilton, Christopher W.; Herrick, Robert R.

2017-12-01

Thermokarst terrains develop when ice-bearing permafrost melts and causes the overlying surface to subside or collapse. This process occurs widely throughout Arctic regions due to environmental and climatological factors, but can also be induced by localized melting of ground ice by active lava flows. The Lost Jim Lava Flow (LJLF) on the Seward Peninsula of Alaska provides evidence of former lava-ground ice interactions. Associated geomorphic features, on the scale of meters to tens of meters, were identified using satellite orthoimages and stereo-derived digital terrain models. The flow exhibits positive- and mixed-relief features, including tumuli ( N = 26) and shatter rings ( N = 4), as well as negative-relief features, such as lava tube skylights ( N = 100) and irregularly shaped topographic depressions ( N = 1188) that are interpreted to include lava-rise pits and lava-induced thermokarst terrain. Along the margins of the flow, there are also clusters of small peripheral pits that may be the products of meltwater or steam escape. On Mars, we observed morphologically similar pits near lava flow margins in northeastern Elysium Planitia, which suggests a common formation mechanism. Investigating the LJLF may therefore help to elucidate processes of lava-ground ice interaction on both Earth and Mars.

Cauda equina-derived extracellular matrix for fabrication of nanostructured hybrid scaffolds applied to neural tissue engineering.

PubMed

Wen, Xiaoxiao; Wang, Yu; Guo, Zhiyuan; Meng, Haoye; Huang, Jingxiang; Zhang, Li; Zhao, Bin; Zhao, Qing; Zheng, Yudong; Peng, Jiang

2015-03-01

Extracellular matrix (ECM) components have become important candidate materials for use as neural scaffolds for neural tissue engineering. In the current study, we prepared cauda equina-derived ECM materials for the production of scaffolds. Natural porcine cauda equina was decellularized using Triton X-100 and sodium deoxycholate, shattered physically, and made into a suspension by differential centrifugation. The decellularization procedure resulted in the removal of >94% of the nuclear material and preserved the extracellular collagen and sulfated glycosaminoglycan. Immunofluorescent staining confirmed the presence of collagen type I, laminin, and fibronectin in the ECM. The cauda equine-derived ECM was blended with poly(l-lactide-co-glycolide) (PLGA) to fabricate nanostructured scaffolds using electrospinning. The incorporation of the ECM increased the hydrophilicity of the scaffolds. Fourier transform infrared spectroscopy and multiphoton-induced autofluorescence images showed the presence of the ECM in the scaffolds. ECM/PLGA scaffolds were beneficial for the survival of Schwann cells compared with scaffolds consisting of PLGA alone, and the aligned fibers could regulate cell morphologic features by modulating cellular orientation. Axons in the dorsal root ganglia explants extended to a greater extent along ECM/PLGA compared with PLGA-alone fibers. The cauda equina ECM might be a promising material for forming scaffolds for use in neural tissue engineering.

Cryogenic lifetime tests on a commercial epoxy resin high voltage bushing

NASA Astrophysics Data System (ADS)

Schwenterly, S. W.; Pleva, E. F.; Ha, T. T.

2012-06-01

High-temperature superconducting (HTS) power devices operating in liquid nitrogen frequently require high-voltage bushings to carry the current leads from the superconducting windings to the room temperature grid connections. Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES), SuperPower (SP), and Southern California Edison (SCE) to develop and demonstrate an HTS utility power transformer. Previous dielectric high voltage tests in support of this program have been carried out in test cryostats with commercial epoxy resin bushings from Electro Composites Inc. (ECI). Though the bushings performed well in these short-term tests, their long-term operation at high voltage in liquid nitrogen (LN) needs to be verified for use on the utility grid. Long-term tests are being carried out on a sample 28-kV-rms-class ECI bushing. The bushing has a monolithic cast, cycloaliphatic resin body and is fire- and shatter-resistant. The test cryostat is located in an interlocked cage and is continuously energized at 25 kVac rms. LN is automatically refilled every 9.5 hours. Partial discharge, capacitance, and leakage resistance tests are periodically performed to check for deviations from factory values. At present, over 2400 hours have been accumulated with no changes in these parameters. The tests are scheduled to run for four to six months.

Fire Season 2015 in Alaska Set to Break Records

NASA Image and Video Library

2017-12-08

Fires have raged throughout Alaska in 2015. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite acquired this image on July 14, 2015. Actively burning areas, detected by the thermal bands on MODIS, are outlined in red. According to the most recent update (July 16, 2015) from the Alaska Interagency Coordination Center, about 304 fires were actively burning when MODIS imaged the area. To date, fires have charred a total of 4,854,924 acres in Alaska. The worst fire season in Alaska's history was in 2004. At this point in time, 2015 is a month ahead of the totals in 2004 putting it on track surpass the fire totals in 2004. The amount of acreage burned in Alaska during June 2015 shattered the previous acreage record set in June 2004 by more than 700,000 acres delivering a sobering piece of news for Alaskan residents. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Similar traits, different genes? Examining convergent evolution in related weedy rice populations.

PubMed

Thurber, Carrie S; Jia, Melissa H; Jia, Yulin; Caicedo, Ana L

2013-02-01

Convergent phenotypic evolution may or may not be associated with convergent genotypic evolution. Agricultural weeds have repeatedly been selected for weed-adaptive traits such as rapid growth, increased seed dispersal and dormancy, thus providing an ideal system for the study of convergent evolution. Here, we identify QTL underlying weedy traits and compare their genetic architecture to assess the potential for convergent genetic evolution in two distinct populations of weedy rice. F(2) offspring from crosses between an indica cultivar and two individuals from genetically differentiated U.S. weedy rice populations were used to map QTL for four quantitative (heading date, seed shattering, plant height and growth rate) and two qualitative traits. We identified QTL on nine of the twelve rice chromosomes, yet most QTL locations do not overlap between the two populations. Shared QTL among weed groups were only seen for heading date, a trait for which weedy groups have diverged from their cultivated ancestors and from each other. Sharing of some QTL with wild rice also suggests a possible role in weed evolution for genes under selection during domestication. The lack of overlapping QTL for the remaining traits suggests that, despite a close evolutionary relationship, weedy rice groups have adapted to the same agricultural environment through different genetic mechanisms. © 2012 Blackwell Publishing Ltd.

NASA's Swift Mission Maps a Star's 'Death Spiral' into a Black Hole

NASA Image and Video Library

2017-12-08

Some 290 million years ago, a star much like the sun wandered too close to the central black hole of its galaxy. Intense tides tore the star apart, which produced an eruption of optical, ultraviolet and X-ray light that first reached Earth in 2014. Now, a team of scientists using observations from NASA's Swift satellite have mapped out how and where these different wavelengths were produced in the event, named ASASSN-14li, as the shattered star's debris circled the black hole. "We discovered brightness changes in X-rays that occurred about a month after similar changes were observed in visible and UV light," said Dheeraj Pasham, an astrophysicist at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts, and the lead researcher of the study. "We think this means the optical and UV emission arose far from the black hole, where elliptical streams of orbiting matter crashed into each other." Read more: go.nasa.gov/2nLmSoa NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Rain-induced spring wheat harvest losses

NASA Technical Reports Server (NTRS)

Bauer, A.; Black, A. L. (Principal Investigator)

1983-01-01

When rain or a combination of rain and high humidity delay wheat harvest, losses can occur in grain yield and/or grain quality. Yield losses can result from shattering, from reduction in test weight, and in the case of windrowed grain, from rooting of sprouting grain at the soil: windrow contact. Losses in grain quality can result from reduction in test weight and from sprouting. Sprouting causes a degradation of grain proteins and starches, hence flour quality is reduced, and the grain price deteriorates to the value of feed grain. Although losses in grain yield and quality are rain-induced, these losses do not necessarily occur because a standing or windrowed crop is wetted by rain. Spike water concentration in hard red spring wheat must be increased to about 45-49% before sprouting is initiated in grain that has overcome dormancy. The time required to overcome this dormancy after the cultivar has dried to 12 to 14% water concentration differs with hard red spring cultivars. The effect of rain on threshing-ready standing and windrowed hard red spring wheat grain yeild and quality was evaluated. A goal was to develop the capability to forecast the extent of expected loss of grain yield and quality from specific climatic events that delay threshing.

Measurement of the accumulation of water ice on optical components in cryogenic vacuum environments

NASA Astrophysics Data System (ADS)

Moeller, Trevor M.; Montgomery Smith, L.; Collins, Frank G.; Labello, Jesse M.; Rogers, James P.; Lowry, Heard S.; Crider, Dustin H.

2012-11-01

Standard vacuum practices mitigate the presence of water vapor and contamination inside cryogenic vacuum chambers. However, anomalies can occur in the facility that can cause the accumulation of amorphous water ice on optics and test articles. Under certain conditions, the amorphous ice on optical components shatters, which leads to a reduction in signal or failure of the component. An experiment was performed to study and measure the deposition of water (H2O) ice on optical surfaces under high-vacuum cryogenic conditions. Water was introduced into a cryogenic vacuum chamber, via a hydrated molecular sieve zeolite, through an effusion cell and impinged upon a quartz-crystal microbalance (QCM) and first-surface gold-plated mirror. A laser and photodiode setup, external to the vacuum chamber, monitored the multiple-beam interference reflectance of the ice-mirror configuration while the QCM measured the mass deposition. Data indicates that water ice, under these conditions, accumulates as a thin film on optical surfaces to thicknesses over 45 microns and can be detected and measured by nonintrusive optical methods which are based upon multiple-beam interference phenomena. The QCM validated the interference measurements. This experiment established proof-of-concept for a miniature system for monitoring ice accumulation within the chamber.

The Experience of Litigation From the Perspective of Midwives in Iran.

PubMed

Peyman, Akram; Nayeri, Nahid Dehghan; Bandboni, Mohammad Esmaeilpour; Moghadam, Zahra Behboodi

Errors and notices to appear in court are a reality of life for many midwives and exert significant effects on both their professional and personal lives. Given the increasing population policies in place, this study was conducted to examine midwives' experiences of litigation in Iran. A qualitative study was conducted in 2014 using an interpretive phenomenological approach. The interviews were recorded and transcribed and were then analyzed using the Diekelmann method. Midwives who participated had professional experience ranging from 3 to 22 years at the time of the complaints. Five participants had received more than one complaint, and 10 participants were judged as guilty creating/leaving significant effects on various dimensions of their lives. The present research disclosed four main themes from the interviews including feeling ruined by the complaints, being conflicted between denial and belief, having shattered hopes of release, and experiencing the slowed-down rhythm of midwifery. From these, a basic pattern of "living in despair" was extracted. Litigation is a painful experience for midwives. Anxiety regarding compensation for the patients' losses, public judgment, prolonged litigations, and undermined professional dignity create physical and psychological ramifications for these midwives. Negative feelings about litigation, compounded by the lack of legal support from the authorities, cause a sense of hopelessness regarding the future of the midwifery profession.

Driven fragmentation of granular gases.

PubMed

Cruz Hidalgo, Raúl; Pagonabarraga, Ignacio

2008-06-01

The dynamics of homogeneously heated granular gases which fragment due to particle collisions is analyzed. We introduce a kinetic model which accounts for correlations induced at the grain collisions and analyze both the kinetics and relevant distribution functions these systems develop. The work combines analytical and numerical studies based on direct simulation Monte Carlo calculations. A broad family of fragmentation probabilities is considered, and its implications for the system kinetics are discussed. We show that generically these driven materials evolve asymptotically into a dynamical scaling regime. If the fragmentation probability tends to a constant, the grain number diverges at a finite time, leading to a shattering singularity. If the fragmentation probability vanishes, then the number of grains grows monotonously as a power law. We consider different homogeneous thermostats and show that the kinetics of these systems depends weakly on both the grain inelasticity and driving. We observe that fragmentation plays a relevant role in the shape of the velocity distribution of the particles. When the fragmentation is driven by local stochastic events, the long velocity tail is essentially exponential independently of the heating frequency and the breaking rule. However, for a Lowe-Andersen thermostat, numerical evidence strongly supports the conjecture that the scaled velocity distribution follows a generalized exponential behavior f(c) approximately exp(-cn) , with n approximately 1.2 , regarding less the fragmentation mechanisms.

The family's experience of the child and/or teenager in palliative care: fluctuating between hope and hopelessness in a world changed by losses.

PubMed

Misko, Maira Deguer; dos Santos, Maiara Rodrigues; Ichikawa, Carolliny Rossi de Faria; de Lima, Regina Aparecida Garcia; Bousso, Regina Szylit

2015-01-01

to understand the family's experience of the child and/or teenager in palliative care and building a representative theoretical model of the process experienced by the family. for this purpose the Symbolic Interactionism and the Theory Based on Data were used. Fifteen families with kids and/or teenagers in palliative care were interviewed, and data were collected through semi-structured interviews. after the comparative analysis of the data, a substantive theory was formed "fluctuating between hope and hopelessness in a world changed by losses", composed by: "having a life shattered ", "managing the new condition", "recognizing the palliative care" and "relearning how to live". Hope, perseverance and spiritual beliefs are determining factors for the family to continue fighting for the life of their child in a context of uncertainty, anguish and suffering, due to the medical condition of the child. Along the way, the family redefines values and integrates palliative care in their lives. staying with the child at home is what was set and kept hope of dreaming about the recovery and support of the child's life, but above all, what takes it away even though temporarily is the possibility of their child's death when staying within the context of the family.

Biogeography as critical nursing pedagogy: Breathing life into nurse education.

PubMed

Kyle, Richard G; Atherton, Iain M

2016-09-01

Insights from the social sciences, including geography, sociology, and anthropology, have long been incorporated into pre-registration nursing programmes. However, scholars have suggested that their inclusion has been sporadic and lacks clear theoretical rationale. In this paper we argue anew that the social sciences - and particularly, human geography - could be central to nurse education. Specifically, we recast the concept of 'biogeography' drawn from human geography that emphasises the interplay between life (bio) and place (geo) to propose pedagogy that theoretically justifies and practically enables the inclusion of the social sciences in nurse education. Biogeography can breathe new life into nursing curricula by animating our students through the cultivation of three 'spirits of nursing'. First, a 'spirit of empathy' that can shatter patient-professional dualisms by facilitating person-centred and place-sensitive care. Second, a 'spirit of engagement' that situates practice in social structures awakening a desire to effect change by fomenting an acute sense of social justice. Third, a 'spirit of enquiry' that holds in critical tension the theory-practice gap by fostering continual questioning and pursuit of evidence. In so doing, biogeographical pedagogy releases the latent potential of the social sciences to revitalise nurse education, reinvigorate our students, and renew ourselves as nurse educators. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analytic Ballistic Performance Model of Whipple Shields

NASA Technical Reports Server (NTRS)

Miller, J. E.; Bjorkman, M. D.; Christiansen, E. L.; Ryan, S. J.

2014-01-01

The dual-wall Whipple shield is the shield of choice for lightweight, long-duration flight. The shield uses an initial sacrificial wall to initiate fragmentation and melt an impacting threat that expands over a void before hitting a subsequent shield wall of a critical component. The key parameters to this type of shield are the rear wall and its mass which stops the debris, as well as the minimum pressure generated under threat particle impact of the sacrificial wall and the amount of void that is available for expansion. Ensuring the minimum pressure is sufficiently high to achieve large scale fragmentation/melt of the threat particle enables the expansion of the threat and reduces the momentum flux of the debris on the rear wall. Three key factors in the minimum pressure achieved are the thickness of the sacrificial wall relative to the characteristic dimension of the impacting particle, the density and material cohesion contrast of the sacrificial wall relative to the threat particle and the impact speed. The mass of the rear wall and the sacrificial wall are desirable to minimize for launch costs and dynamic concerns making it important to have an understanding of the effects of density contrast and impact speed. In this paper a fourth key parameter is identified related to fragmentation, which corresponds to the ratio of the size of the projectile relative to the transition from brittle to ductile hole growth in the projectile. Ballistic limit equations have been developed to define the failure limits of a MMOD shield, generally in terms of projectile diameter (or mass), impact velocity, and angle. Within the range of impact velocities relevant for Earth-orbiting spacecraft, three distinct regions of penetration phenomenology have been identified for Whipple shields: center dot Low velocity: the projectile is eroded (and possibly deformed) during its passage through the bumper plate, but is not fragmented. Thus, perforation of the rear wall is by a fragment with a mass and speed equal to or less than the original impactor. center dot Intermediate (shatter) velocity: impact velocities are sufficient to induce projectile fragmentation upon impact with the bumper plate, resulting in a coarse debris cloud with large solid fragments. Increasing velocity within the shatter regime results in increased fragmentation, and eventually melting, of the projectile and bumper fragments, generating a finer and more evenly dispersed debris cloud. Failure of the rear wall is a complicated combination of modes observed at low- and hypervelocity. center dot Hypervelocity: the projectile and holed-out bumper material is completely, or nearly completely, melted and/or vaporized by the initial impact. The resultant debris cloud impacts over a dispersed area of the rear wall, loading it impulsively and inducing failure through rupture or petalling. While each of these regimes are well observed with extensive empirical methods to describe these regions, differences in impactor materials, configurations of shields and questions about the limitations of the attainable impact speeds have left questions that are difficult to answer from completely empirical methods.

Potential weathering by freeze-thaw action in alpine rocks in the European Alps during a nine year monitoring period

NASA Astrophysics Data System (ADS)

Kellerer-Pirklbauer, Andreas

2017-11-01

A quantification of rock weathering by freeze-thaw processes in alpine rocks requires at least rock temperature data in high temporal resolution, in high quality, and over a sufficient period of time. In this study up to nine years of rock temperature data (2006-2015) from eleven rock monitoring sites in two of the highest mountain ranges of Austria were analyzed. Data were recorded at a half-hourly or hourly logging interval and at rock depths of 3, 10, and 30-40 cm. These data have been used to quantify mean conditions, ranges, and relationships of the potential near-surface weathering by freeze-thaw action considering volumetric-expansion of ice and ice segregation. For the former, freeze-thaw cycles and effective freeze-thaw cycles for frost shattering have been considered. For the latter, the intensity and duration of freezing events as well as time within the 'frost cracking window' have been analyzed. Results show that the eleven sites are in rather extreme topoclimatic positions and hence represent some of the highest and coolest parts of Austria and therefore the Eastern Alps. Only four sites are presumably affected by permafrost. Most sites are influenced by a long-lasting seasonal snow cover. Freeze-thaw cycles and effective freeze-thaw cycles for frost shattering are mainly affecting the near-surface and are unimportant at few tens of centimeters below the rock surface. The lowest temperatures during freezing events and the shortest freezing events have been quantified at all eleven monitoring sites very close to the surface. The time within the frost cracking window decreases in most cases from the rock surface inwards apart from very cold years/sites with very low temperatures close to the surface. As shown by this study and predicted climate change scenarios, assumed warmer rock temperature conditions in the future at alpine rock walls in Austria will lead to less severe freezing events and to shorter time periods within the frost-cracking window. Statistical correlation analyses showed furthermore that the longer the duration of the seasonal snow cover, the fewer are freeze-thaw cycles, the fewer are effective freeze-thaw cycles, the longer is the mean and the maximum duration of freezing events, and the lower is the mean annual ground temperature. The interaction of the winter snow cover history and the winter thermal regime has a complex effect on the duration of the frost cracking window but also on the number of freeze-thaw cycles as shown by a conceptual model. Predicted future warmer and snow-depleted winters in the European Alps will therefore have a complex impact on the potential weathering of alpine rocks by frost action which makes potential weathering predictions difficult. Neglecting rock moisture and rock properties in determining rock weathering limits the usefulness of solely rock temperature data. However, rock temperature data allow getting an estimate about potential weathering by freeze-thaw action which is often substantially more than previously known.

Breakup of the Larsen Ice Shelf, Antarctica

NASA Technical Reports Server (NTRS)

2002-01-01

Recent Moderate-resolution Imaging Spectroradiometer (MODIS) satellite imagery analyzed at the University of Colorado's National Snow and Ice Data Center revealed that the northern section of the Larsen B ice shelf, a large floating ice mass on the eastern side of the Antarctic Peninsula, has shattered and separated from the continent. This particular image was taken on March 5, 2002. The shattered ice formed a plume of thousands of icebergs adrift in the Weddell Sea. A total of about 3,250 square kilometers of shelf area disintegrated in a 35-day period beginning on January 31, 2002. Over the last five years, the shelf has lost a total of 5,700 square kilometers and is now about 40 percent the size of its previous minimum stable extent. Ice shelves are thick plates of ice, fed by glaciers, that float on the ocean around much of Antarctica. The Larsen B shelf was about 220 meters thick. Based on studies of ice flow and sediment thickness beneath the ice shelf, scientists believe that it existed for at least 400 years prior to this event and likely existed since the end of the last major glaciation 12,000 years ago. For reference, the area lost in this most recent event dwarfs Rhode Island (2,717 square kilometers) in size. In terms of volume, the amount of ice released in this short time is 720 billion tons--enough ice for about 12 trillion 10-kilogram bags. This is the largest single event in a series of retreats by ice shelves along the peninsula over the last 30 years. The retreats are attributed to a strong climate warming in the region. The rate of warming is approximately 0.5 degrees Celsius per decade, and the trend has been present since at least the late 1940s. Overall in the peninsula, the extent of seven ice shelves has declined by a total of about 13,500 square kilometers since 1974. This value excludes areas that would be expected to calve under stable conditions. Ted Scambos, a researcher with the National Snow and Ice Data Center (NSIDC) at University of Colorado, and a team of collaborating investigators developed a theory of how the ice disintegrates. The theory is based on the presence of ponded melt water on the surface in late summer as the climate has warmed in the area. Meltwater acts to enhance fracturing of the shelf by filling smaller cracks. The weight of the meltwater forces the cracks through the thickness of the ice. The idea was suggested in model form by other researchers in the past (Weertman, 1973; Hughes, 1983); satellite images have provided substantial observational proof that it is in fact the main process responsible for the peninsula shelf disintegration. Christina Hulbe of Portland State University and Mark Fahnestock of University of Maryland collaborated with Scambos on the research. For more information see: Antarctic Ice Shelf Collapses Image courtesy Ted Scambos, National Snow and Ice Data Center, University of Colorado, Boulder, based on data from MODIS

Deep-Sea Submarine 'Ben Franklin'

NASA Technical Reports Server (NTRS)

1969-01-01

The deep-sea submarine 'Ben Franklin' is being docked in the harbor. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life. It also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effect of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Interior View of the Deep-Sea Research Submarine 'Ben Franklin'

NASA Technical Reports Server (NTRS)

1969-01-01

This is an interior view of the living quarters of the deep-sea research submarine 'Ben Franklin.' Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep- ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effect of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Deep-Sea Research Submarine 'Ben Franklin'

NASA Technical Reports Server (NTRS)

1969-01-01

This is an aerial view of the deep-sea research submarine 'Ben Franklin' at dock. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Alleviation of lead-induced physiological, metabolic, and ultramorphological changes in leaves of upland cotton through glutathione.

PubMed

Khan, Mumtaz; Daud, M K; Basharat, Ali; Khan, Muhammad Jamil; Azizullah, Azizullah; Muhammad, Niaz; Muhammad, Noor; Ur Rehman, Zia; Zhu, Shui Jin

2016-05-01

Plants face changes in leaves under lead (Pb) toxicity. Reduced glutathione (GSH) has several functions in plant metabolism, but its role in alleviating Pb toxicity in cotton leaves is still unknown. In the present study, cotton seedlings (28 days old) were exposed to 500 μM Pb and 50 μM GSH, both alone and in combination, for a period of 10 days, in the Hoagland solution under controlled growth conditions. Results revealed Pb-induced changes in cotton's leaf morphology, photosynthesis, and oxidative metabolism. However, exogenous application of GSH restored leaf growth. GSH triggered build up of chlorophyll a, chlorophyll b, and carotenoid contents and boosted fluorescence ratios (F v/F m and F v/F 0). Moreover, GSH reduced the malondialdehyde (MDA), hydrogen peroxide (H2O2), and Pb contents in cotton leaves. Results further revealed that total soluble protein contents were decreased under Pb toxicity; however, exogenously applied GSH improved these contents in cotton leaves. Activities of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), glutathione reductase (GR), and ascorbate peroxidase (APX)) were also increased by GSH application under Pb toxicity. Microscopic analysis showed that excess Pb shattered thylakoid membranes in chloroplasts. However, GSH stabilized ultrastructure of Pb-stressed cotton leaves. These findings suggested that exogenously applied GSH lessened the adverse effects of Pb and improved cotton's tolerance to oxidative stress.

Shattering a myth - Whooping cough susceptible to antibiotics.

PubMed

Syed, Muhammad Ali; Jamil, Bushra; Bokhari, Habib

2016-05-01

Bordetella parapertussis is the causative agent of a milder form of pertussis or whooping cough. Little is reported about the antibiotic resistance patterns and mechanism of drug resistance of Bordetella parapertussis. The objective of this study has been to investigate antimicrobial resistance, distribution of integrons and presence of gene cassettes to quinolones (qnr) and sulfonamides (sul) among B. parapertussis strains' isolated from Pakistan. Thirty-five (35) samples were collected from various hospitals of Pakistan from children (median age 3 years) with pertussis-like symptoms, all were tested and confirmed to be B. Parapertussis. Resistance profile of Ampicillin, Cephalexin, Sulphamethoxazole, Chloramphenicol, Ofloxacin, Nalidixic acid, Gentamycin and Erythromycin were investigated through all samples. Majority of the isolates were found to be resistant to the afore-mentioned antibiotics except erythromycin. All isolates were resistant to quinolones phenotypically, but qnr genes were detected in only 25.7% (9/35) of isolates. On the other hand, 71.4% (25/35) isolates were resistant to sulfonamides phenotypically. From these 71% strains showing phenotypical resistance, 96% (24/25) were found to possess sul genes. Only two isolates were carrying class 1 integrons, which also harbored sul gene and qnr gene cassettes. It can be safely concluded that the phenotypic resistance patterns seemed mostly independent of presence of integrons. However, interestingly both integrons harboring strains were resistant to quinolones and sulfonamides and also possessed qnr and sul genes.

Skylab

NASA Image and Video Library

1969-07-01

This is an aerial view of the deep-sea research submarine "Ben Franklin" at dock. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Skylab

NASA Image and Video Library

1969-07-01

In this photograph, the deep-sea Research Submarine "Ben Franklin" drifts off the East Coast of the United States (U.S.) prior to submerging into the ocean. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Skylab

NASA Image and Video Library

1969-07-01

This is an interior view of the living quarters of the deep-sea research submarine "Ben Franklin." Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep- ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effect of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

The family's experience of the child and/or teenager in palliative care: fluctuating between hope and hopelessness in a world changed by losses1

PubMed Central

Misko, Maira Deguer; dos Santos, Maiara Rodrigues; Ichikawa, Carolliny Rossi de Faria; de Lima, Regina Aparecida Garcia; Bousso, Regina Szylit

2015-01-01

OBJECTIVES: to understand the family's experience of the child and/or teenager in palliative care and building a representative theoretical model of the process experienced by the family. METHODOLOGY: for this purpose the Symbolic Interactionism and the Theory Based on Data were used. Fifteen families with kids and/or teenagers in palliative care were interviewed, and data were collected through semi-structured interviews. RESULTS: after the comparative analysis of the data, a substantive theory was formed "fluctuating between hope and hopelessness in a world changed by losses", composed by: "having a life shattered ", "managing the new condition", "recognizing the palliative care" and "relearning how to live". Hope, perseverance and spiritual beliefs are determining factors for the family to continue fighting for the life of their child in a context of uncertainty, anguish and suffering, due to the medical condition of the child. Along the way, the family redefines values and integrates palliative care in their lives. CONCLUSION: staying with the child at home is what was set and kept hope of dreaming about the recovery and support of the child's life, but above all, what takes it away even though temporarily is the possibility of their child's death when staying within the context of the family. PMID:26312639

The Genomic and Transcriptomic Landscape of a HeLa Cell Line

PubMed Central

Landry, Jonathan J. M.; Pyl, Paul Theodor; Rausch, Tobias; Zichner, Thomas; Tekkedil, Manu M.; Stütz, Adrian M.; Jauch, Anna; Aiyar, Raeka S.; Pau, Gregoire; Delhomme, Nicolas; Gagneur, Julien; Korbel, Jan O.; Huber, Wolfgang; Steinmetz, Lars M.

2013-01-01

HeLa is the most widely used model cell line for studying human cellular and molecular biology. To date, no genomic reference for this cell line has been released, and experiments have relied on the human reference genome. Effective design and interpretation of molecular genetic studies performed using HeLa cells require accurate genomic information. Here we present a detailed genomic and transcriptomic characterization of a HeLa cell line. We performed DNA and RNA sequencing of a HeLa Kyoto cell line and analyzed its mutational portfolio and gene expression profile. Segmentation of the genome according to copy number revealed a remarkably high level of aneuploidy and numerous large structural variants at unprecedented resolution. Some of the extensive genomic rearrangements are indicative of catastrophic chromosome shattering, known as chromothripsis. Our analysis of the HeLa gene expression profile revealed that several pathways, including cell cycle and DNA repair, exhibit significantly different expression patterns from those in normal human tissues. Our results provide the first detailed account of genomic variants in the HeLa genome, yielding insight into their impact on gene expression and cellular function as well as their origins. This study underscores the importance of accounting for the strikingly aberrant characteristics of HeLa cells when designing and interpreting experiments, and has implications for the use of HeLa as a model of human biology. PMID:23550136

Structure of a normal seismogenic fault zone in carbonates: The Vado di Corno Fault, Campo Imperatore, Central Apennines (Italy)

NASA Astrophysics Data System (ADS)

Demurtas, Matteo; Fondriest, Michele; Balsamo, Fabrizio; Clemenzi, Luca; Storti, Fabrizio; Bistacchi, Andrea; Di Toro, Giulio

2016-09-01

The Vado di Corno Fault Zone (VCFZ) is an active extensional fault cutting through carbonates in the Italian Central Apennines. The fault zone was exhumed from ∼2 km depth and accommodated a normal throw of ∼2 km since Early-Pleistocene. In the studied area, the master fault of the VCFZ dips N210/54° and juxtaposes Quaternary colluvial deposits in the hangingwall with cataclastic dolostones in the footwall. Detailed mapping of the fault zone rocks within the ∼300 m thick footwall-block evidenced the presence of five main structural units (Low Strain Damage Zone, High Strain Damage Zone, Breccia Unit, Cataclastic Unit 1 and Cataclastic Unit 2). The Breccia Unit results from the Pleistocene extensional reactivation of a pre-existing Pliocene thrust. The Cataclastic Unit 1 forms a ∼40 m thick band lining the master fault and recording in-situ shattering due to the propagation of multiple seismic ruptures. Seismic faulting is suggested also by the occurrence of mirror-like slip surfaces, highly localized sheared calcite-bearing veins and fluidized cataclasites. The VCFZ architecture compares well with seismological studies of the L'Aquila 2009 seismic sequence (mainshock MW 6.1), which imaged the reactivation of shallow-seated low-angle normal faults (Breccia Unit) cut by major high-angle normal faults (Cataclastic Units).

A binary main-belt comet.

PubMed

Agarwal, Jessica; Jewitt, David; Mutchler, Max; Weaver, Harold; Larson, Stephen

2017-09-20

Asteroids are primitive Solar System bodies that evolve both collisionally and through disruptions arising from rapid rotation. These processes can lead to the formation of binary asteroids and to the release of dust, both directly and, in some cases, through uncovering frozen volatiles. In a subset of the asteroids called main-belt comets, the sublimation of excavated volatiles causes transient comet-like activity. Torques exerted by sublimation measurably influence the spin rates of active comets and might lead to the splitting of bilobate comet nuclei. The kilometre-sized main-belt asteroid 288P (300163) showed activity for several months around its perihelion 2011 (ref. 11), suspected to be sustained by the sublimation of water ice and supported by rapid rotation, while at least one component rotates slowly with a period of 16 hours (ref. 14). The object 288P is part of a young family of at least 11 asteroids that formed from a precursor about 10 kilometres in diameter during a shattering collision 7.5 million years ago. Here we report that 288P is a binary main-belt comet. It is different from the known asteroid binaries in its combination of wide separation, near-equal component size, high eccentricity and comet-like activity. The observations also provide strong support for sublimation as the driver of activity in 288P and show that sublimation torques may play an important part in binary orbit evolution.

The glass ceiling in Irish healthcare: a nursing perspective.

PubMed

Tracey, Catherine

2006-01-01

The purpose of this study is to describe and explore from the perspectives of top-level nurses holding the formal position of director of nursing their perceptions and interpretations of their experiences in the Irish healthcare system. This paper presents some findings from a nation-wide study, which is qualitative in approach using grounded theory methodology. Semi-structured interviews were conducted with 50 directors of nursing representing general and psychiatric nursing. The study in this paper was conducted in the context of a changing healthcare system, which emphasises the flattening of organisational pyramids. However, this study's findings indicate that, while structures might be changing, behaviours remain unaltered. In particular, the medicine nursing power base remains unchanged, while the power shift between nursing and general management continues to widen in favour of general management. Research in this paper shows that directors of nursing who chose to participate in this study may have different perceptions of experiences from those who chose not to participate. In the paper the reality is neither medicine nor general management, individually or collectively, are going to share or devolve power and influence to nursing. This study's findings indicate that nursing needs to confront this power imbalance. Nursing needs to take the first steps towards shattering the glass ceiling by really examining its own behaviours, in maintaining the status quo, in the traditional balance of power.

Exploring hope and healing in patients living with advanced non-small cell lung cancer.

PubMed

Eustache, Chloe; Jibb, Emily; Grossman, Mary

2014-09-01

To explore the experience and meaning of hope in relation to the healing process of patients living with stage IIIb or IV non-small cell lung cancer. Interpretative qualitative study design. Peter Brojde Lung Cancer Centre in the Jewish General Hospital in Montreal, Quebec, Canada. 12 English- and French-speaking patients, aged 36-78 years. One 60-90-minute semistructured interview per participant was conducted. An inductive approach to data analysis was taken, involving immersion in the data, coding, classifying, and creating linkages. Four main themes emerged: (a) the morass of shattered hope, (b) tentative steps toward a new hope paradigm, (c) reframing hope within the context of a life-threatening illness, and (d) strengthening the link between hope and wellness. Patients described a process where hope was diminished or lost entirely, regained, and reshaped as they learned to live and grow following their diagnosis. This study adds to the literature by describing the dynamic nature of hope as well as factors facilitating or hindering the hope process. It demonstrates how finding meaning, a structural component of healing, can be used to envision a new hopeful future. This study suggests hope and healing cannot exist in isolation, and highlights the importance of understanding the fluctuating nature of hope in patients with advanced lung cancer to foster it, therefore promoting healing.

The Great Mother and the Terrible Mother: mimesis, alterity and attachment in adolescence.

PubMed

Rytovaara, Marica

2014-04-01

This paper discusses attachment, the longing for familiarity and sameness (mimesis), the search for difference and separateness (alterity) and the problem with the Other seen through the lens ofthe individuation process in adolescence. These are explored with reference to relational aspects and Levinas and Girard's divergent views of the Other. The relational space, which in Phillip Bromberg's (2003) words is 'uniquely relational, but still uniquely individual' and in which analyst and patient 'stand together in the space between realities', might under exceptional circumstances be transformed into 'a twilight space where the impossible becomes possible' (p. 573). I will sketch a developmental trajectory starting from primitive states, in which the presence of the Other,as a separate entity cannot be tolerated and where the patient strives for total mimesis. Should the analyst prematurely shatter this illusion, she becomes an alien 'Other'; a wolf in sheep's clothing. I trace the current psychoanalytic paradigm shift to an emphasis on the co-creation of meaning in the interpersonal space and explore what alterity consists of and how much of the other's unknowability can be tolerated and respected without a translation into one's own idiom. The clinical vignettes illustrate aspects of therapy which normally lie outside the analytical remit and are culled from an inpatient setting and private practice. © 2014, The Society of Analytical Psychology.

Termination of pregnancy for fetal abnormality: a meta-ethnography of women's experiences.

PubMed

Lafarge, Caroline; Mitchell, Kathryn; Fox, Pauline

2014-11-01

Due to technological advances in antenatal diagnosis of fetal abnormalities, more women face the prospect of terminating pregnancies on these grounds. Much existing research focuses on women's psychological adaptation to this event. However, there is a lack of holistic understanding of women's experiences. This article reports a systematic review of qualitative studies into women's experiences of pregnancy termination for fetal abnormality. Eight databases were searched up to April 2014 for peer-reviewed studies, written in English, that reported primary or secondary data, used identifiable and interpretative qualitative methods, and offered a valuable contribution to the synthesis. Altogether, 4,281 records were screened; 14 met the inclusion criteria. The data were synthesised using meta-ethnography. Four themes were identified: a shattered world, losing and regaining control, the role of health professionals and the power of cultures. Pregnancy termination for fetal abnormality can be considered as a traumatic event that women experience as individuals, in their contact with the health professional community, and in the context of their politico-socio-legal environment. The range of emotions and experiences that pregnancy termination for fetal abnormality generates goes beyond the abortion paradigm and encompasses a bereavement model. Coordinated care pathways are needed that enable women to make their own decisions and receive supportive care. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Saturn's secrets revealed - A special report

NASA Astrophysics Data System (ADS)

Sutton, C.

1980-11-01

Scientific results of the encounter of Voyager 1 with Saturn are reported. Instruments on the Voyager spacecraft, which was launched on September 5, 1977 and flew within 124,200 km of the Saturn cloud tops on November 12, 1980, revealed the presence of several hundred rings within the six visible from earth, as well as eccentric rings, braiding and clumps within the narrow F ring, and spoke-like structures in the B ring. During its flight beneath the ring plane, Voyager 1 also discovered that the rings extend toward the visible surface of the cloud tops, and are composed of ice chunks or silicate with an icy coating about a meter in diameter. Observations of Titan revealed the satellite to have a dense atmosphere, composed primarily of molecular nitrogen, with as many as three layers of haze above the cloud tops. Three additional moons of Saturn were discovered apparently focusing ring particles, and the moon Janus, discovered from earth in 1966, was shown to be actually two moons. Close approaches to other Saturn satellites show Mimas, Tethys, Dione and Rhea to be heavily cratered, icy bodies, some with features indicating they had been struck by objects almost large enough to shatter them. Surface features on Saturn, which is covered by a deep layer of haze, and the details of the Saturn magnetosphere have also been observed.

Neuroanatomical distribution of five semantic components of verbs: evidence from fMRI.

PubMed

Kemmerer, David; Castillo, Javier Gonzalez; Talavage, Thomas; Patterson, Stephanie; Wiley, Cynthia

2008-10-01

The Simulation Framework, also known as the Embodied Cognition Framework, maintains that conceptual knowledge is grounded in sensorimotor systems. To test several predictions that this theory makes about the neural substrates of verb meanings, we used functional magnetic resonance imaging (fMRI) to scan subjects' brains while they made semantic judgments involving five classes of verbs-specifically, Running verbs (e.g., run, jog, walk), Speaking verbs (e.g., shout, mumble, whisper), Hitting verbs (e.g., hit, poke, jab), Cutting verbs (e.g., cut, slice, hack), and Change of State verbs (e.g., shatter, smash, crack). These classes were selected because they vary with respect to the presence or absence of five distinct semantic components-specifically, ACTION, MOTION, CONTACT, CHANGE OF STATE, and TOOL USE. Based on the Simulation Framework, we hypothesized that the ACTION component depends on the primary motor and premotor cortices, that the MOTION component depends on the posterolateral temporal cortex, that the CONTACT component depends on the intraparietal sulcus and inferior parietal lobule, that the CHANGE OF STATE component depends on the ventral temporal cortex, and that the TOOL USE component depends on a distributed network of temporal, parietal, and frontal regions. Virtually all of the predictions were confirmed. Taken together, these findings support the Simulation Framework and extend our understanding of the neuroanatomical distribution of different aspects of verb meaning.

Wernher von Braun

NASA Image and Video Library

1969-07-01

This photograph depicts Dr. von Braun (at right, showing his back) and other NASA officials surveying the deep-sea research submarine "Ben Franklin." Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Wernher von Braun

NASA Image and Video Library

1969-07-01

This photograph depicts Dr. von Braun (fourth from far right) and other NASA officials surveying the deep-sea research submarine "Ben Franklin." Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Proterozoic Bushveld-Vredefort catastrophe: Possible causes and consequences

NASA Technical Reports Server (NTRS)

Elston, W. E.; Twist, D.

1988-01-01

Bushveld Complex and Vredefort Dome are unique features, formed in close proximity during the same time interval, approximately 2 Ga. Both show evidence of catastrophic events in the shallow marine environment of the otherwise stable Kaapvaal Craton. Explanation by multiple impacts of an asteroid, brecciated by an inter-asteroidal collision and disintegrating in Earth's gravity field is supported by pseudotachylite, shatter cones, coesite, and stishovite at Vredefort but these shock phenomena were not found in the Bushveld Complex. The Bushveld Complex was formerly interpreted as a lopolith, a view incompatible with gravity, electrical resistivity, magnetic, and seismic-reflection data. It is outlined by five inward-dipping lobes of layered ultramafic-mafic plutonic rocks that partly coalesce to form a basin-like feature 400 km in diameter and 65,000 sq. km. in area, equivalent to a small lunar mare. The Bushveld Complex is orders of magnitudes larger than other proposed terrestrial impact structures and differs from them in important ways. Its principal members, in order of age, are Rooiberg Felsite, RLS, and Lebowa Granite. The Bushveld-Vredefort events occurred during the interval from neutral or reducing atmosphere to oxidizing atmosphere. This transition is usually related to the evolution of photosynthesizing organisms. If the impact hypothesis for Bushveld-Vredefort can be confirmed, it may represent a global catastrophe sufficient to contribute to environmental changes favoring aerobic photosynthesizing eukaryotes over anaerobic prokaryotes.

On Graphene in the Interstellar Medium

NASA Astrophysics Data System (ADS)

Chen, X. H.; Li, Aigen; Zhang, Ke

2017-11-01

The possible detection of C24, a planar graphene that was recently reported to be in several planetary nebulae by García-Hernández et al., inspires us to explore whether and how much graphene could exist in the interstellar medium (ISM) and how it would reveal its presence through its ultraviolet (UV) extinction and infrared (IR) emission. In principle, interstellar graphene could arise from the photochemical processing of polycyclic aromatic hydrocarbon (PAH) molecules, which are abundant in the ISM, due to the complete loss of their hydrogen atoms, and/or from graphite, which is thought to be a major dust species in the ISM, via fragmentation caused by grain–grain collisional shattering. Both quantum-chemical computations and laboratory experiments have shown that the exciton-dominated electronic transitions in graphene cause a strong absorption band near 2755 \\mathringA . We calculate the UV absorption of graphene and place an upper limit of ∼5 ppm of C/H (i.e., ∼1.9% of the total interstellar C) on the interstellar graphene abundance. We also model the stochastic heating of graphene C24 in the ISM, excited by single starlight photons of the interstellar radiation field and calculate its IR emission spectra. We also derive the abundance of graphene in the ISM to be <5 ppm of C/H by comparing the model emission spectra with that observed in the ISM.

Re-evaluating the 38th Parallel Serial Impact Hypothesis

NASA Astrophysics Data System (ADS)

Evans, K. R.; Davis, G. H.; Miao, X.; Mickus, K. L.; Miller, J. F.; Morrow, J. R.

2008-12-01

The idea that the 38th-parallel structures across Kansas, Missouri, and Illinois are serial impacts has been controversial. In addition to the original eight, two other structures are proximal to the 38th parallel, Dent Branch and Silver City Dome. Only Weaubleau, Decaturville, and Crooked Creek contain quartz grains with multiple directions of planar deformational features (PDFs). Shatter cones have been found at Decaturville and Crooked Creek. Key macroscopic observations of these impacts include: (1) circular outlines and notable central uplifts, (2) remarkably intense levels of structural deformation (folding, faulting, fracturing, and brecciation), (3) deformation dying out with depth and laterally away from the central uplift, and (4) associated igneous rocks only as clasts. From field and core studies and published reports, we consider other structures along the 38th parallel to be dubious (Hazelgreen), intrusive, (Hick's Dome), or volcanic in origin (Silver City Dome, Rose Dome, Furnace Creek, Dent Branch, and Avon). The age of the Weaubleau structure is constrained biostratigraphically as middle Mississippian (latest Osagean or early Meramecian). Crooked Creek and Decaturville are deeply eroded; their ages are poorly constrained. Crooked Creek contains isolated blocks of sandstone of late Osagean age, but the stratigraphic context of the blocks is poorly known. Other investigators contend the age of Decaturville is Pennsylvanian or Permian, based on CRM paleomagnetism and occurrence of an isolated sulfide breccia body in the central uplift. The Ozark plateau experienced Missouri Valley Type (MVT) sulfide mineralization during the Ouachita orogeny, but our examination of a sample from the sulfide breccia shows it is shattered pyrite and differs from typical MVT deposits. If the breccia is not associated with the regional mineralization, a middle Mississippian age cannot be excluded. Weaubleau, Decaturville, and Crooked Creek are aligned across 199 km. A line connecting the centers of the central uplifts of Weaubleau and Crooked Creek passes 1.5 km north of the center of Decaturville. Monte Carlo simulation was used to examine the probability that three temporally unrelated impacts could be aligned (±2° angular discordance) randomly over relatively short distances in an area that approximates the continental land surface. Modeling variables included number of impacts (N=200, N=300...N=1,000) and search radii (100-600 km). Twenty repetitions of 10,000 runs provided for analysis of standard deviation. For N=200 and radius of 100 km, an average of 6.6±2.5 aligned sets were found. For N=300, the results were 25.9±3.7, yielding a probability of P=0.003. Larger sample sizes and wider search radii produced more probable results, but given the number of known impacts (~175), it is highly improbable that Weaubleau, Decaturville, and Crooked Creek structures could be aligned but not temporally related. If Weaubleau, Decaturville, and Crooked Creek were products of a serial impact, they were not analogous with the Shoemaker-Levy 9 impacts on Jupiter, where planetary rotation affected the distribution, so the impacts would have occurred within seconds. In Mississippian paleogeographic reconstructions, the direction of impact would have been WSW-ENE, arguably along the ecliptic and near the equator. The distribution of deformation at Weaubleau suggests an oblique impact from present-day WSW-ENE, an argument against the serial impact hypothesis.

Cloning and analysis of a cDNA encoding an endo-polygalacturonase expressed during the desiccation period of the silique-valves of turnip-tops (Brassica rapa L. cv. Rapa).

PubMed

Rodríguez-Gacio, María del Carmen; Nicolás, Carlos; Matilla, Angel J

2004-02-01

During zygotic embryogenesis of turnip-tops (Brassica rapa L. cv. Rapa), the polygalacturonase activity (PG; EC 3.2.1.15), measured as a decrease in viscosity of polygalacturonic acid, reached a high when the desiccation process in the seeded silique was triggered and the valves had lost more than 70-75% of their moisture (45-50 DPA). The PG activity was not detected in any phases of developing seeds. This work also characterizes a cDNA with an open reading frame of 1303 bp and that codes for a putative PG called BrPG1. This falls into the category of clade-B, which includes PG related to shattering and abscission processes. The deduced BrPG1 sequence predicted a 434-residue-long precursor protein (46.7kDa) with a transit peptide sequence 23 amino acids long. A molecular mass of 44.3 kDa was calculated for the mature form of BrPG1, which showed high sequence similarity to PGA1 (97%) of B. napus (X98373) and ADPG1 (87%) of Arabidopsis thaliana (AJ002532). All conserved amino acids at the catalytic site of PGs belonging to clade-B were preserved on BrPG1. This BrPG1 gene was specifically expressed in the silique valves of turnip-tops and was temporally expressed at the beginning of its desiccation.

Guidelines for Design and Analysis of Large, Brittle Spacecraft Components

NASA Technical Reports Server (NTRS)

Robinson, E. Y.

1993-01-01

There were two related parts to this work. The first, conducted at The Aerospace Corporation was to develop and define methods for integrating the statistical theory of brittle strength with conventional finite element stress analysis, and to carry out a limited laboratory test program to illustrate the methods. The second part, separately funded at Aerojet Electronic Systems Division, was to create the finite element postprocessing program for integrating the statistical strength analysis with the structural analysis. The second part was monitored by Capt. Jeff McCann of USAF/SMC, as Special Study No.11, which authorized Aerojet to support Aerospace on this work requested by NASA. This second part is documented in Appendix A. The activity at Aerojet was guided by the Aerospace methods developed in the first part of this work. This joint work of Aerospace and Aerojet stemmed from prior related work for the Defense Support Program (DSP) Program Office, to qualify the DSP sensor main mirror and corrector lens for flight as part of a shuttle payload. These large brittle components of the DSP sensor are provided by Aerojet. This document defines rational methods for addressing the structural integrity and safety of large, brittle, payload components, which have low and variable tensile strength and can suddenly break or shatter. The methods are applicable to the evaluation and validation of such components, which, because of size and configuration restrictions, cannot be validated by direct proof test.

Dr. von Braun on top of the Deep-Sea Research Submarine 'Ben Franklin'

NASA Technical Reports Server (NTRS)

1969-01-01

This photograph depicts Dr. von Braun (at right, showing his back) and other NASA officials surveying the deep-sea research submarine 'Ben Franklin.' Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Dr. von Braun on Top of the Deep-Sea Research Submarine 'Ben Franklin'

NASA Technical Reports Server (NTRS)

1969-01-01

This photograph depicts Dr. von Braun (fourth from far right) and other NASA officials surveying the deep-sea research submarine 'Ben Franklin.' Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Deep-Sea Research Submarine 'Ben Franklin' at the East Coast of the United States

NASA Technical Reports Server (NTRS)

1969-01-01

In this photograph, the deep-sea Research Submarine 'Ben Franklin' drifts off the East Coast of the United States (U.S.) prior to submerging into the ocean. Named for American patriot and inventor Ben Franklin, who discovered the Gulf Steam, the 50-foot Ben Franklin was built between 1966 and 1968 in Switzerland for deep-ocean explorer Jacques Piccard and the Grumman Aircraft Engineering Corporation. The submersible made a famous 30-day drift dive off the East Coast of the United States and Canada in 1969 mapping the Gulf Stream's currents and sea life, and also made space exploration history by studying the behavior of aquanauts in a sealed, self-contained, self-sufficient capsule for NASA. On July 14, 1969, the Ben Franklin was towed to the high-velocity center of the Stream off the coast of Palm Beach, Florida. With a NASA observer on board, the sub descended to 1,000 feet off of Riviera Beach, Florida and drifted 1,400 miles north with the current for more than four weeks, reemerging near Maine. During the course of the dive, NASA conducted exhaustive analyses of virtually every aspect of onboard life. They measured sleep quality and patterns, sense of humor and behavioral shifts, physical reflexes, and the effects of a long-term routine on the crew. The submarine's record-shattering dive influenced the design of Apollo and Skylab missions and continued to guide NASA scientists as they devised future marned space-flight missions.

Geology and impact features of Vargeão Dome, southern Brazil

NASA Astrophysics Data System (ADS)

Crósta, Alvaro P.; Kazzuo-Vieira, César; Pitarello, Lidia; Koeberl, Christian; Kenkmann, Thomas

2012-01-01

Vargeão Dome (southern Brazil) is a circular feature formed in lava flows of the Lower Cretaceous Serra Geral Formation and in sandstones of the Paraná Basin. Even though its impact origin was already proposed in the 1980s, little information about its geological and impact features is available in the literature. The structure has a rim-rim diameter of approximately 12 km and comprises several ring-like concentric features with multiple concentric lineaments. The presence of a central uplift is suggested by the occurrence of deformed sandstone strata of the Botucatu and Pirambóia formations. We present the morphological/structural characteristics of Vargeão Dome, characterize the different rock types that occur in its interior, mainly brecciated volcanic rocks (BVR) of the Serra Geral Formation, and discuss the deformation and shock features in the volcanic rocks and in sandstones. These features comprise shatter cones in sandstone and basalt, as well as planar microstructures in quartz. A geochemical comparison of the target rock equivalents from outside the structure with the shocked rocks from its interior shows that both the BVRs and the brecciated sandstone have a composition largely similar to that of the corresponding unshocked lithologies. No traces of meteoritic material have been found so far. The results confirm the impact origin of Vargeão Dome, making it one of the largest among the rare impact craters in basaltic targets known on Earth.

Penetrating head injury from angle grinder: A cautionary tale.

PubMed

Senthilkumaran, S; Balamurgan, N; Arthanari, K; Thirumalaikolundusubramanian, P

2010-01-01

Penetrating cranial injury is a potentially life-threatening condition. Injuries resulting from the use of angle grinders are numerous and cause high-velocity penetrating cranial injuries. We present a series of two penetrating head injuries associated with improper use of angle grinder, which resulted in shattering of disc into high velocity missiles with reference to management and prevention. One of those hit on the forehead of the operator and the other on the occipital region of the co-worker at a distance of five meters. The pathophysiological consequence of penetrating head injuries depends on the kinetic energy and trajectory of the object. In the nearby healthcare center the impacted broken disc was removed without realising the consequences and the wound was packed. As the conscious level declined in both, they were referred. CT brain revealed fracture in skull and changes in the brain in both. Expeditious removal of the penetrating foreign body and focal debridement of the scalp, skull, dura, and involved parenchyma and Watertight dural closure were carried out. The most important thing is not to remove the impacted foreign body at the site of accident. Craniectomy around the foreign body, debridement and removal of foreign body without zigzag motion are needed. Removal should be done following original direction of projectile injury. The neurological sequelae following the non missile penetrating head injuries are determined by the severity and location of initial injury as well as the rapidity of the exploration and fastidious debridement.

All roads lead to weediness: Patterns of genomic divergence reveal extensive recurrent weedy rice origins from South Asian Oryza.

PubMed

Huang, Zhongyun; Young, Nelson D; Reagon, Michael; Hyma, Katie E; Olsen, Kenneth M; Jia, Yulin; Caicedo, Ana L

2017-06-01

Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O. sativa), infests and persists in cultivated rice fields worldwide. Many weedy rice populations have evolved similar adaptive traits, considered part of the 'agricultural weed syndrome', making this an ideal model to study the genetic basis of parallel evolution. Understanding parallel evolution hinges on accurate knowledge of the genetic background and origins of existing weedy rice groups. Using population structure analyses of South Asian and US weedy rice, we show that weeds in South Asia have highly heterogeneous genetic backgrounds, with ancestry contributions both from cultivated varieties (aus and indica) and wild rice. Moreover, the two main groups of weedy rice in the USA, which are also related to aus and indica cultivars, constitute a separate origin from that of Asian weeds. Weedy rice populations in South Asia largely converge on presence of red pericarps and awns and on ease of shattering. Genomewide divergence scans between weed groups from the USA and South Asia, and their crop relatives are enriched for loci involved in metabolic processes. Some candidate genes related to iconic weedy traits and competitiveness are highly divergent between some weed-crop pairs, but are not shared among all weed-crop comparisons. Our results show that weedy rice is an extreme example of recurrent evolution, and suggest that most populations are evolving their weedy traits through different genetic mechanisms. © 2017 John Wiley & Sons Ltd.

Is there still a glass ceiling for women in academic surgery?

PubMed

Zhuge, Ying; Kaufman, Joyce; Simeone, Diane M; Chen, Herbert; Velazquez, Omaida C

2011-04-01

Despite the dramatically increased entry of women into general surgery and surgical subspecialties, traditionally male-dominated fields, there remains a gross under-representation of women in the leadership positions of these departments. Women begin their careers with fewer academic resources and tend to progress through the ranks slower than men. Female surgeons also receive significantly lower salaries than their male counterparts and are more vulnerable to discrimination, both obvious and covert. Although some argue that female surgeons tend to choose their families over careers, studies have actually shown that women are as eager as men to assume leadership positions, are equally qualified for these positions as men, and are as good as men at leadership tasks.Three major constraints contribute to the glass-ceiling phenomenon: traditional gender roles, manifestations of sexism in the medical environment, and lack of effective mentors. Gender roles contribute to unconscious assumptions that have little to do with actual knowledge and abilities of an individuals and they negatively influence decision-making when it comes to promotions. Sexism has many forms, from subtle to explicit forms, and some studies show that far more women report being discriminately against than do men. There is a lack of same-sex mentors and role models for women in academic surgery, thereby isolating female academicians further. This review summarizes the manifestation of the glass-ceiling phenomenon, identifies some causes of these inequalities, and proposes different strategies for continuing the advancement of women in academic surgery and to shatter the glass ceiling.

Nonlinear Acoustics in Ultrasound Metrology and other Selected Applications.

PubMed

Lewin, Peter A

2010-01-01

A succinct background explaining why, initially, both the scientific community and industry were skeptical about the existence of the nonlinear (NL) wave propagation in tissue will be given and the design of an adequately wideband piezoelectric polymer hydrophone probe that was eventually used to verify that the 1-5 MHz probing wave then used in diagnostic ultrasound imaging was undergoing nonlinear distortion and generated harmonics in tissue will be discussed. The far-reaching implications of the advent of the piezoelectric PVDF polymer material will be reviewed and the advances in ultrasound metrology prompted by the regulatory agencies such as US Food and Drug Administration (FDA) and International Electrotechnical Commission (IEC) will be presented. These advances include the development of absolute calibration techniques for hydrophones along with the methods of accounting for spatial averaging corrections up to 100 MHz and the development of "point-receiver" hydrophone probes utilizing acousto-optic sensors. Next, selected therapeutic applications of nonlinear ultrasonics (NLU), including lithotripters will be briefly discussed. Also, the use of shock waves as pain relief tool and in abating penicillin resistant bacteria that develop rock hard "biofilm" that can be shattered by the finite amplitude wave will also be mentioned. The growing applications of NLU in cosmetic industry where it is used for redistribution and reduction of fatty tissue within the body will be briefly reviewed, and, finally, selected examples of NLU applications in retail and entertainment industry will also be pointed out.

The impact crater as a habitat: effects of impact processing of target materials.

PubMed

Cockell, Charles S; Osinski, Gordon R; Lee, Pascal

2003-01-01

Impact structures are a rare habitat on Earth. However, where they do occur they can potentially have an important influence on the local ecology. Some of the types of habitat created in the immediate post-impact environment are not specific to the impact phenomenon, such as hydrothermal systems and crater lakes that can be found, for instance, in post-volcanic environments, albeit with different thermal characteristics than those associated with impact. However, some of the habitats created are specifically linked to processes of impact processing. Two examples of how impact processing of target materials has created novel habitats that improve the opportunities for colonization are found in the Haughton impact structure in the Canadian High Arctic. Impact-shocked rocks have become a habitat for endolithic microorganisms, and large, impact-shattered blocks of rock are used as resting sites by avifauna. However, some materials produced by an impact, such as melt sheet rocks, can make craters more biologically depauperate than the area surrounding them. Although there are no recent craters with which to study immediate post-impact colonization, these data yield insights into generalized mechanisms of how impact processing can influence post-impact succession. Because impact events are one of a number of processes that can bring localized destruction to ecosystems, understanding the manner in which impact structures are recolonized is of ecological interest. Impact craters are a universal phenomenon on solid planetary surfaces, and so they are of potential biological relevance on other planetary surfaces, particularly Mars.

The impact crater as a habitat: effects of impact processing of target materials

NASA Technical Reports Server (NTRS)

Cockell, Charles S.; Osinski, Gordon R.; Lee, Pascal

2003-01-01

Impact structures are a rare habitat on Earth. However, where they do occur they can potentially have an important influence on the local ecology. Some of the types of habitat created in the immediate post-impact environment are not specific to the impact phenomenon, such as hydrothermal systems and crater lakes that can be found, for instance, in post-volcanic environments, albeit with different thermal characteristics than those associated with impact. However, some of the habitats created are specifically linked to processes of impact processing. Two examples of how impact processing of target materials has created novel habitats that improve the opportunities for colonization are found in the Haughton impact structure in the Canadian High Arctic. Impact-shocked rocks have become a habitat for endolithic microorganisms, and large, impact-shattered blocks of rock are used as resting sites by avifauna. However, some materials produced by an impact, such as melt sheet rocks, can make craters more biologically depauperate than the area surrounding them. Although there are no recent craters with which to study immediate post-impact colonization, these data yield insights into generalized mechanisms of how impact processing can influence post-impact succession. Because impact events are one of a number of processes that can bring localized destruction to ecosystems, understanding the manner in which impact structures are recolonized is of ecological interest. Impact craters are a universal phenomenon on solid planetary surfaces, and so they are of potential biological relevance on other planetary surfaces, particularly Mars.

"Shattering culture": perspectives on cultural competence and evidence-based practice in mental health services.

PubMed

Good, Mary-Jo DelVecchio; Hannah, Seth Donal

2015-04-01

The concept of culture as an analytic concept has increasingly been questioned by social scientists, just as health care institutions and clinicians have increasingly routinized concepts and uses of culture as means for improving the quality of care for racial and ethnic minorities. This paper examines this tension, asking whether it is possible to use cultural categories to develop evidenced-based practice guidelines in mental health services when these categories are challenged by the increasing hyperdiversity of patient populations and newer theories of culture that question direct connection between group-based social identities and cultural characteristics. Anthropologists have grown concerned about essentializing societies, yet unequal treatment on the basis of cultural, racial, or ethnic group membership is present in medicine and mental health care today. We argue that discussions of culture-patients' culture and the "culture of medicine"-should be sensitive to the risk of improper stereotypes, but should also be sensitive to the continuing significance of group-based discrimination and the myriad ways culture shapes clinical presentation, doctor-patient interactions, the illness experience, and the communication of symptoms. We recommend that mental health professionals consider the local contexts, with greater appreciation for the diversity of lived experience found among individual patients. This suggests a nuanced reliance on broad cultural categories of racial, ethnic, and national identities in evidence-based practice guidelines. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Fleshy Fruit Expansion and Ripening Are Regulated by the Tomato SHATTERPROOF Gene TAGL1[W][OA

PubMed Central

Vrebalov, Julia; Pan, Irvin L.; Arroyo, Antonio Javier Matas; McQuinn, Ryan; Chung, MiYoung; Poole, Mervin; Rose, Jocelyn; Seymour, Graham; Grandillo, Silvana; Giovannoni, James; Irish, Vivian F.

2009-01-01

The maturation and ripening of fleshy fruits is a developmental program that synchronizes seed maturation with metabolism, rendering fruit tissues desirable to seed dispersing organisms. Through RNA interference repression, we show that Tomato AGAMOUS-LIKE1 (TAGL1), the tomato (Solanum lycopersicum) ortholog of the duplicated SHATTERPROOF (SHP) MADS box genes of Arabidopsis thaliana, is necessary for fruit ripening. Tomato plants with reduced TAGL1 mRNA produced yellow-orange fruit with reduced carotenoids and thin pericarps. These fruit are also decreased in ethylene, indicating a comprehensive inhibition of maturation mediated through reduced ACC Synthase 2 expression. Furthermore, ectopic expression of TAGL1 in tomato resulted in expansion of sepals and accumulation of lycopene, supporting the role of TAGL1 in ripening. In Arabidopsis, the duplicate SHP1 and SHP2 MADS box genes regulate the development of separation layers essential for pod shatter. Expression of TAGL1 in Arabidopsis failed to completely rescue the shp1 shp2 mutant phenotypes, indicating that TAGL1 has evolved distinct molecular functions compared with its Arabidopsis counterparts. These analyses demonstrate that TAGL1 plays an important role in regulating both fleshy fruit expansion and the ripening process that together are necessary to promote seed dispersal of fleshy fruit. From this broad perspective, SHP1/2 and TAGL1, while distinct in molecular function, regulate similar activities via their necessity for seed dispersal in Arabidopsis and tomato, respectively. PMID:19880793

Resection after neoadjuvant chemotherapy in advanced carcinoma of the gallbladder: a retrospective study.

PubMed

Selvakumar, Veda Padma Priya; Zaidi, Shuaib; Pande, Pankaj; Goel, Ashish; Kumar, Kapil

2015-03-01

Although rare over most of the world, Gallbladder cancer is very common in northern india. A delayed presentation, aggressive nature,lack of randomised trials and a poor prognosis have all contributed to the nihilistic halo encircling gallbladder cancer. None of the advances in oncology have been exploited enough to shatter the nihilistic halo. In this background we sought to analyze if the addition of neoadjuvant chemotherapy had any impact on the resectability, overall and disease free survival in patients with advanced carcinoma of the gallbladder. We reviewed the records of all patients who underwent surgery for carcinoma of the gall bladder from 2004 to 2010 at our institute retrospectively. Twenty-one patients received neoadjuvant chemotherapy and subsequently taken up for surgery. Outcome analysis of these 21 patients were done by Kaplan meier method and graphs plotted. Out of the 21 patients who were taken up for surgery after neoadjuvant chemotherapy, fourteen patients underwent R0 resection (Group 1). Seven patients had been rendered inoperable on exploration (Group 2). Thus about 66.67 % of patients deemed resectable after neoadjuvant chemotherapy on imaging underwent R0 resection. The mean overall survival of the group 1 was 42.8 months versus 6.6 months of group 2(Hazard Ratio: 3.42). Neoadjuvant chemotherapy improves resectability in some patients with unresectable gall bladder cancer. Resection after neoadjuvant chemotherapy is feasible and may improve survival in a select group of patients. However randomized studies are required to establish its definitive role.

Loss of function at RAE2, a previously unidentified EPFL, is required for awnlessness in cultivated Asian rice.

PubMed

Bessho-Uehara, Kanako; Wang, Diane R; Furuta, Tomoyuki; Minami, Anzu; Nagai, Keisuke; Gamuyao, Rico; Asano, Kenji; Angeles-Shim, Rosalyn B; Shimizu, Yoshihiro; Ayano, Madoka; Komeda, Norio; Doi, Kazuyuki; Miura, Kotaro; Toda, Yosuke; Kinoshita, Toshinori; Okuda, Satohiro; Higashiyama, Tetsuya; Nomoto, Mika; Tada, Yasuomi; Shinohara, Hidefumi; Matsubayashi, Yoshikatsu; Greenberg, Anthony; Wu, Jianzhong; Yasui, Hideshi; Yoshimura, Atsushi; Mori, Hitoshi; McCouch, Susan R; Ashikari, Motoyuki

2016-08-09

Domestication of crops based on artificial selection has contributed numerous beneficial traits for agriculture. Wild characteristics such as red pericarp and seed shattering were lost in both Asian (Oryza sativa) and African (Oryza glaberrima) cultivated rice species as a result of human selection on common genes. Awnedness, in contrast, is a trait that has been lost in both cultivated species due to selection on different sets of genes. In a previous report, we revealed that at least three loci regulate awn development in rice; however, the molecular mechanism underlying awnlessness remains unknown. Here we isolate and characterize a previously unidentified EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family member named REGULATOR OF AWN ELONGATION 2 (RAE2) and identify one of its requisite processing enzymes, SUBTILISIN-LIKE PROTEASE 1 (SLP1). The RAE2 precursor is specifically cleaved by SLP1 in the rice spikelet, where the mature RAE2 peptide subsequently induces awn elongation. Analysis of RAE2 sequence diversity identified a highly variable GC-rich region harboring multiple independent mutations underlying protein-length variation that disrupt the function of the RAE2 protein and condition the awnless phenotype in Asian rice. Cultivated African rice, on the other hand, retained the functional RAE2 allele despite its awnless phenotype. Our findings illuminate the molecular function of RAE2 in awn development and shed light on the independent domestication histories of Asian and African cultivated rice.

Reconnaissance survey of the Duolun ring structure in Inner Mongolia: Not an impact structure

NASA Astrophysics Data System (ADS)

Xu, Xiaoming; Kenkmann, Thomas; Xiao, Zhiyong; Sturm, Sebastian; Metzger, Nicolai; Yang, Yu; Weimer, Daniela; Krietsch, Hannes; Zhu, Meng-Hua

2017-09-01

The Duolun basin, which is located in Inner Mongolia, China, has been proposed to be an impact structure with an apparent rim diameter of about 70, or even 170 km. The designation as an impact structure was based on its nearly circular topography, consisting of an annular moat that surrounds an inner hummocky region, and the widespread occurrences of various igneous rocks, polymict breccias, and deformed crustal rocks. Critical shock metamorphic evidence is not available to support the impact hypothesis. We conducted two independent reconnaissance field surveys to this area and studied the lithology both within and outside of the ring structure. We collected samples from all lithologies that might contain evidence of shock metamorphism as suggested by their locations, especially those sharing similar appearances with impact breccias, suevites, impact melt rocks, and shatter cones. Field investigation, together with thin-section examination, discovered that the suspected impact melt rocks are actually Early Cretaceous and Late Jurassic lava flows and pyroclastic deposits of rhyolitic to trachytic compositions, and the interpreted impact glass is typical volcanic glass. Petrographic analyses of all the samples reveal no indications for shock metamorphic overprint. All these lines of evidence suggest that the Duolun basin was not formed through impact cratering. The structural deformation and spatial distribution pattern of the igneous rocks suggest that the Duolun basin is most likely a Jurassic-Cretaceous complex rhyolite caldera system that has been partly filled with sediments forming an annular basin, followed by resurgent doming of the central area.

Six-rowed barley originated from a mutation in a homeodomain-leucine zipper I-class homeobox gene

PubMed Central

Komatsuda, Takao; Pourkheirandish, Mohammad; He, Congfen; Azhaguvel, Perumal; Kanamori, Hiroyuki; Perovic, Dragan; Stein, Nils; Graner, Andreas; Wicker, Thomas; Tagiri, Akemi; Lundqvist, Udda; Fujimura, Tatsuhito; Matsuoka, Makoto; Matsumoto, Takashi; Yano, Masahiro

2007-01-01

Increased seed production has been a common goal during the domestication of cereal crops, and early cultivators of barley (Hordeum vulgare ssp. vulgare) selected a phenotype with a six-rowed spike that stably produced three times the usual grain number. This improved yield established barley as a founder crop for the Near Eastern Neolithic civilization. The barley spike has one central and two lateral spikelets at each rachis node. The wild-type progenitor (H. vulgare ssp. spontaneum) has a two-rowed phenotype, with additional, strictly rudimentary, lateral rows; this natural adaptation is advantageous for seed dispersal after shattering. Until recently, the origin of the six-rowed phenotype remained unknown. In the present study, we isolated vrs1 (six-rowed spike 1), the gene responsible for the six-rowed spike in barley, by means of positional cloning. The wild-type Vrs1 allele (for two-rowed barley) encodes a transcription factor that includes a homeodomain with a closely linked leucine zipper motif. Expression of Vrs1 was strictly localized in the lateral-spikelet primordia of immature spikes, suggesting that the VRS1 protein suppresses development of the lateral rows. Loss of function of Vrs1 resulted in complete conversion of the rudimentary lateral spikelets in two-rowed barley into fully developed fertile spikelets in the six-rowed phenotype. Phylogenetic analysis demonstrated that the six-rowed phenotype originated repeatedly, at different times and in different regions, through independent mutations of Vrs1. PMID:17220272

Using Nested Contractions and a Hierarchical Tensor Format To Compute Vibrational Spectra of Molecules with Seven Atoms.

PubMed

Thomas, Phillip S; Carrington, Tucker

2015-12-31

We propose a method for solving the vibrational Schrödinger equation with which one can compute hundreds of energy levels of seven-atom molecules using at most a few gigabytes of memory. It uses nested contractions in conjunction with the reduced-rank block power method (RRBPM) described in J. Chem. Phys. 2014, 140, 174111. Successive basis contractions are organized into a tree, the nodes of which are associated with eigenfunctions of reduced-dimension Hamiltonians. The RRBPM is used recursively to compute eigenfunctions of nodes in bases of products of reduced-dimension eigenfunctions of nodes with fewer coordinates. The corresponding vectors are tensors in what is called CP-format. The final wave functions are therefore represented in a hierarchical CP-format. Computational efficiency and accuracy are significantly improved by representing the Hamiltonian in the same hierarchical format as the wave function. We demonstrate that with this hierarchical RRBPM it is possible to compute energy levels of a 64-D coupled-oscillator model Hamiltonian and also of acetonitrile (CH3CN) and ethylene oxide (C2H4O), for which we use quartic potentials. The most accurate acetonitrile calculation uses 139 MB of memory and takes 3.2 h on a single processor. The most accurate ethylene oxide calculation uses 6.1 GB of memory and takes 14 d on 63 processors. The hierarchical RRBPM shatters the memory barrier that impedes the calculation of vibrational spectra.

Characteristics of Nd:YAG sculptured contact probes after prolonged laser application.

PubMed

Barroso, E G; Haklin, M F; Staren, E D

1995-01-01

This study analyzed the functional and structural characteristics of cone, hemisphere, and modified sculptured contact fibers (1,000 microns) after 1 hour of continuous Nd:YAG laser application. Continuous laser application was performed on live porcine tissue using 20 watts of power. The fiber's appearance under a microscope as well as the power output was recorded after 0, 5, 10, 20, 30, 45, and 60 minutes of continuous laser application. (N = 3 for each fiber). At time 0, all fibers transmitted from 49 to 56% of the initial 20 watts (W); power transmission decreased to less than 9% relative power transmission after 20 minutes and then plateaued. The fibers exhibited severe distortion and carbonization of the surface where laser had been applied with evidence of quartz melting and shattering after only 10 minutes. By 30 minutes of laser application, all three fibers were fractured and essentially indistinguishable from one another; moreover, the fibers exhibited similar power transmission, and cutting and coagulation activity, as determined by a panel of independent, double-blinded surgeons. These data lead us to conclude that 1) Nd:YAG contact laser effects result from thermal heating of the fiber tip with subsequent tissue injury, 2) the unique structural configuration of the fiber's sculptured tip are lost after several minutes of laser application without appreciable change in functional integrity, and 3) fibers may be manually fractured allowing for multiple uses without significant sacrifice of power transmission or surgical utility.

Literature and disability: the medical interface in Borges and Beckett.

PubMed

Novillo-Corvalán, Patricia

2011-06-01

Samuel Beckett and Jorge Luis Borges have presented 20th century literature with a distinctive gallery of solitary figures who suffer from a series of physiological ailments: invalidism, decrepitude, infirmity and blindness, as well as neurological conditions such as amnesia and autism spectrum disorders. Beckett and Borges were concerned with the dynamics between illness and creativity, the literary representation of physical and mental disabilities, the processes of remembering and forgetting, and the inevitability of death. This article explores the depiction of physically and mentally disabled characters in Borges' Funes the Memorious (1942)--a story about an Uruguayan gaucho who has been left paralysed after a fall from a horse which simultaneously endowed him with an infallible memory and perception--and Beckett's Trilogy: Molloy (1951), Malone Dies (1951) and The Unnamable (1953). It examines the prodigious memory of Funes and the forgetful minds of Molloy and Malone with reference to influential neuropsychological studies such as Alexander Luria's twofold exploration of memory and forgetfulness in The Mind of a Mnemonist (1968) and The Man with a Shattered World (1972). The article demonstrates that in contrast to Beckett's amnesiacs and Luria's brain-damaged patient, who are able to transcend their circumstances through cathartic writing, Borges' and Luria's mnemonic prodigies fail to achieve anything significant with their unlimited memories and remain imprisoned within their cognitive disabilities. It reveals that medical discourses can provide invaluable insights and lead to a deeper understanding of the minds and bodily afflictions of literary characters.

Scientific Research: Commodities or Commons?

NASA Astrophysics Data System (ADS)

Vermeir, Koen

2013-10-01

Truth is for sale today, some critics claim. The increased commodification of science corrupts it, scientific fraud is rampant and the age-old trust in science is shattered. This cynical view, although gaining in prominence, does not explain very well the surprising motivation and integrity that is still central to the scientific life. Although scientific knowledge becomes more and more treated as a commodity or as a product that is for sale, a central part of academic scientific practice is still organized according to different principles. In this paper, I critically analyze alternative models for understanding the organization of knowledge, such as the idea of the scientific commons and the gift economy of science. After weighing the diverse positive and negative aspects of free market economies of science and gift economies of science, a commons structured as a gift economy seems best suited to preserve and take advantage of the specific character of scientific knowledge. Furthermore, commons and gift economies promote the rich social texture that is important for supporting central norms of science. Some of these basic norms might break down if the gift character of science is lost. To conclude, I consider the possibility and desirability of hybrid economies of academic science, which combine aspects of gift economies and free market economies. The aim of this paper is to gain a better understanding of these deeper structural challenges faced by science policy. Such theoretical reflections should eventually assist us in formulating new policy guidelines.

Aetiology, epidemiology and management strategies for blunt scrotal trauma.

PubMed

Dalton, D M; Davis, N F; O'Neill, D C; Brady, C M; Kiely, E A; O'Brien, M F

2016-02-01

To describe our experience of all patients presenting to a tertiary referral centre over a 3 year time period with blunt scrotal trauma and to describe a methodical approach for managing this group of patients. A retrospective analysis was performed on all patients presenting to the Emergency Department (ED) of a level 1 trauma centre with blunt scrotal trauma from 2010 to 2013 inclusive. Inclusion criteria included a recent history of blunt scrotal trauma with associated pain and/or swelling of the affected testis on clinical examination. Twenty-seven male patients with a median age of 19 (range 8-65) years were included and all but 1 patient underwent scrotal ultrasonography upon presentation. Sixteen patients (59%) presented with scrotal trauma secondary to a sports related injury. Fifteen patients were managed conservatively and of the 12 who underwent urgent exploration 9 had a testicular rupture, including 1 who had an emergency orchidectomy due to a completely shattered testis. Four patients had >30% of the testis replaced by necrotic tissue/haematoma; of which 2 ultimately underwent orchidectomy and insertion of testicular prosthesis. Our findings demonstrate that the necessity for scrotal protection in sports that predispose to scrotal trauma should be reviewed. We also demonstrate the importance of scrotal ultrasonography for determining an appropriate management strategy (i.e., conservative versus surgical treatment) in this young patient cohort. Copyright © 2014 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

New Observational Evidence of Active Asteroid P/2010 A2: Slow Rotation of the Largest Fragment

NASA Astrophysics Data System (ADS)

Kim, Yoonyoung; Ishiguro, Masateru; Lee, Myung Gyoon

2017-06-01

We report new observations of the active asteroid P/2010 A2 taken when it made its closest approach to Earth (1.06 au in 2017 January) after its first discovery in 2010. Despite a crucial role of the rotational period in clarifying its ejection mechanism, the rotational property of P/2010 A2 has not yet been studied due to the extreme faintness of this tiny object (∼120 m in diameter). Taking advantage of the best observing geometry since the discovery, we succeed in obtaining the rotational light curve of the largest fragment with Gemini/GMOS-N. We find that (1) the largest fragment has a double-peaked period of 11.36 ± 0.02 hr spinning much slower than its critical spin period; (2) the largest fragment is a highly elongated object (a/b ≥ 1.94) with an effective radius of {61.9}-9.2+16.8 m; (3) the size distribution of the ejecta follows a broken power law (the power indices of the cumulative size distributions of the dust and fragments are 2.5 ± 0.1 and 5.2 ± 0.1, respectively); (4) the mass ratio of the largest fragment to the total ejecta is around 0.8; and (5) the dust cloud morphology is in agreement with the anisotropic ejection model in Kim et al. These new characteristics of the ejecta obtained in this work are favorable to the impact shattering hypothesis.

Landslide Hazard Assessment near Kedarnath Temple in Himalayan region considering cloudburst tragedy in 2013

NASA Astrophysics Data System (ADS)

Ansari, T. A.; Singh, T. N., Sr.

2017-12-01

The world famous Shri Kedarnath Temple in Uttarakhand state of India is located in the western extremity of the young and dynamically active Central Himalaya. As Indian plate is moving towards Eurasian plate which has steep slopes, highly variable altitudes and uncertain climatic conditions. Due to high seismic activity Himalayan rock mass is highly fractured, shattered and inherently weakness pose threat for landslide. On 16th and 17th June 2013, was witness an extreme climatic events of century in the history of the region, the high intensity rainfall, (> 400mm) caused number of landslide which have adverse economic and societal impacts, including the potential for heavy loss of human and widespread devastation of natural resources, infrastructures. The study region is at high altitude around 3583 meters, which is affected from impact of glacial melt due to climate change and future increase in rainfall subjected to high level uncertainty of landslides. Aerial and field survey has been done of the region and most vulnerable landslide locations of hill slope and road cut slope are studied for future prospect of safety. SLIDE 6.0, PHASE27 (numerical software) for slope stability, geomechanical profile of rock and kinematics analysis to know the type of failures. Rock quality tunneling index (Q), Geological strength (GSI), Slope mass Rating (SMR) and factor of safety were determined to know the slope instability. Our finding provides an important aspect for future safety as provide the information for landslide warning system and engineering countermeasures.

Nonlinear acoustics in ultrasound metrology and other selected applications

NASA Astrophysics Data System (ADS)

Lewin, Peter A.

2010-01-01

A succinct background explaining why, initially, both the scientific community and industry were skeptical about the existence of the nonlinear (NL) wave propagation in tissue will be given and the design of an adequately wideband piezoelectric polymer hydrophone probe that was eventually used to verify that the 1-5 MHz probing wave then used in diagnostic ultrasound imaging was undergoing nonlinear distortion and generated harmonics in tissue will be discussed. The far-reaching implications of the advent of the piezoelectric PVDF polymer material will be reviewed and the advances in ultrasound metrology prompted by the regulatory agencies such as US Food and Drug Administration (FDA) and International Electrotechnical Commission (IEC) will be presented. These advances include the development of absolute calibration techniques for hydrophones along with the methods of accounting for spatial averaging corrections up to 100 MHz and the development of 'point-receiver' hydrophone probes utilizing acousto-optic sensors. Next, selected therapeutic applications of nonlinear ultrasonics (NLU), including lithotripters will be briefly discussed. Also, the use of shock waves as pain relief tool and in abating penicillin resistant bacteria that develop rock hard 'biofilm' that can be shattered by the finite amplitude wave will also be mentioned. The growing applications of NLU in cosmetic industry where it is used for redistribution and reduction of fatty tissue within the body will be briefly reviewed, and, finally, selected examples of NLU applications in retail and entertainment industry will also be pointed out.

Dissociation and identity transformation in female survivors of the genocide against the Tutsi in Rwanda: a qualitative research study.

PubMed

Sandole, Denise H; Auerbach, Carl F

2013-01-01

This qualitative research study deals with female survivors of the 1994 genocide against the Tutsi in Rwanda. It examines dissociation and identity change in these women before, during, and after the genocide. Three theories were used to frame the findings. The 1st was assumptive world theory ( R. Janoff-Bulman, 1992 ), which postulates that traumatic events may shatter people's everyday assumptions about the world. The 2nd was catastrophic dissociation theory ( G. Boulanger, 2007 ), which refers to the gradual breakdown of the self as it repeatedly "experiences its psychic foundations in ways that do not happen in the average expectable life" (G. Boulanger, 2008 ,p. 646). The 3rd was structural dissociation theory ( O. Van der Hart, E. R. S. Nijenhuis, & K. Steele, 2006 ), which postulates that when people encounter events that they cannot integrate into their mental lives, their personality may fragment and divide. The data were transcripts of interviews with 30 female genocide survivors. Data analysis revealed that these women experienced trauma-induced identity transformations. Before the genocide, they existed as a "Civilized Self," with a stable identity in a secure, assumptive world. During the genocide, they existed as a "Survivor Self," the massive trauma of the genocide having disrupted their prior self-experience and identity. After the genocide, they existed as an "Aftermath Self," in which their Civilized and Survivor Selves coexisted in an unintegrated, dissociated form.

MoXy fiber with active cooling cap for bovine prostate vaporization with high power 200W 532 nm laser

NASA Astrophysics Data System (ADS)

Peng, Steven Y.; Kang, Hyun Wook; Pirzadeh, Homa; Stinson, Douglas

2011-03-01

A novel MoXyTM fiber delivery device with Active Cooling Cap (ACCTM) is designed to transmit up to 180W of 532 nm laser light to treat benign prostatic hyperplasia (BPH). Under such high power tissue ablation, effective cooling is key to maintaining fiber power transmission and ensuring the reliability of the fiber delivery device To handle high power and reduce fiber degradation, the MoXy fiber features a larger core size (750 micrometer) and an internal fluid channel to ensure better cooling of the fiber tip to prevent the cap from burning, detaching, or shattering during the BPH treatment. The internal cooling channel was created with a metal cap and tubing that surrounds the optical fiber. In this study MoXy fibers were used to investigate the effect of power levels of 120 and 200 W on in-vitro bovine prostate ablation using a 532 nm XPSTM laser system. For procedures requiring more than 100 kJ, the MoXy fiber at 200W removed tissue at twice the rate of the current HPS fiber at 120W. The fiber maintained a constant tissue vaporization rate during the entire tissue ablation process. The coagulation at 200W was about 20% thicker than at 120W. In conclusion, the new fibers at 200W doubled the tissue removal rate, maintained vaporization efficiency throughout delivery of 400kJ energy, and induced similar coagulation to the existing HPS fiber at 120W.

Eolian additions to late Quaternary alpine soils, Indian Peaks Wilderness Area, Colorado Front Range

USGS Publications Warehouse

Muhs, D.R.; Benedict, J.B.

2006-01-01

Surface horizons of many alpine soils on Quaternary deposits in high-mountain settings are enriched in silt. The origin of these particles has been debated, particularly in the Rocky Mountain region of North America. The most common explanations are frost shattering of coarser particles and eolian additions from distant sources. We studied soil A horizons on alpine moraines of late-glacial (Satanta Peak) age in the Colorado Front Range. Surface horizons of soils on these moraines are enriched in silt and have a particle size distribution that resembles loess and dust deposits found elsewhere. The compositions of sand and silt fractions of the soils were compared to possible local source rocks, using immobile trace elements Ti, Nb, Zr, Ce, and Y. The sand fractions of soils have a wide range of trace element ratios, similar to the range of values in the local biotite gneiss bedrock. In contrast, silt fractions have narrower ranges of trace element ratios that do not overlap the range of these ratios in biotite gneiss. The particle size and geochemical results support an interpretation that silts in these soils are derived from airborne dust. Eolian silts were most likely derived from distant sources, such as the semiarid North Park and Middle Park basins to the west. We hypothesize that much of the eolian influx to soils of the Front Range occurred during an early to mid-Holocene warm period, when sediment availability in semiarid source basins was at a maximum.

Battered bodies & shattered minds: violence against women in Bangladesh.

PubMed

Wahed, Tania; Bhuiya, Abbas

2007-10-01

Violence against women is a common and insidious phenomenon in Bangladesh. The types of violence commonly committed are domestic violence, acid throwing, rape, trafficking and forced prostitution. Domestic violence is the most common form of violence and its prevalence is higher in rural areas. A higher prevalence of verbal abuse than physical abuse by partners has been observed. The reasons mentioned for abuse were trivial and included questioning of the husband, failure to perform household work and care of children, economic problems, stealing, refusal to bring dowry, etc. The factors associated with violence were the age of women, age of husband, past exposure to familial violence, and lack of spousal communication. The majority of abused women remained silent about their experience because of the high acceptance of violence within society, fear of repercussion, tarnishing family honour and own reputation, jeopardizing children's future, and lack of an alternative place to stay. However, severely abused women, women who had frequent verbal disputes, higher level of education, and support from natal homes were more likely to disclose violence. A very small proportion of women approached institutional sources for help and only when the abuse was severe, became life threatening or children were at risk. Interestingly, violence increased with membership of women in micro-credit organizations initially but tapered off as duration of involvement increased. The high acceptability of violence within society acts as a deterrent for legal redress. Effective strategies for the prevention of violence should involve public awareness campaigns and community-based networks to support victims.

Gravity anomaly and density structure of the San Andreas fault zone

NASA Astrophysics Data System (ADS)

Wang, Chi-Yuen; Rui, Feng; Zhengsheng, Yao; Xingjue, Shi

1986-01-01

A densely spaced gravity survey across the San andreas fault zone was conducted near Bear Valley, about 180 km south of San Francisco, along a cross-section where a detailed seismic reflection profile was previously made by McEvilly (1981). With Feng and McEvilly's velocity structure (1983) of the fault zone at this cross-section as a constraint, the density structure of the fault zone is obtained through inversion of the gravity data by a method used by Parker (1973) and Oldenburg (1974). Although the resulting density picture cannot be unique, it is better constrained and contains more detailed information about the structure of the fault than was previously possible. The most striking feature of the resulting density structure is a deeply seated tongue of low-density material within the fault zone, probably representing a wedge of fault gouge between the two moving plates, which projects from the surface to the base of the seismogenic zone. From reasonable assumptions concerning the density of the solid grains and the state of saturation of the fault zone the average porosity of this low-density fault gouge is estimated as about 12%. Stress-induced cracks are not expected to create so much porosity under the pressures in the deep fault zone. Large-scaled removal of fault-zone material by hydrothermal alteration, dissolution, and subsequent fluid transport may have occurred to produce this pronounced density deficiency. In addition, a broad, funnel-shaped belt of low density appears about the upper part of the fault zone, which probably represents a belt of extensively shattered wall rocks.

Brachypodium distachyon. A New Model System for Functional Genomics in Grasses1

PubMed Central

Draper, John; Mur, Luis A.J.; Jenkins, Glyn; Ghosh-Biswas, Gadab C.; Bablak, Pauline; Hasterok, Robert; Routledge, Andrew P.M.

2001-01-01

A new model for grass functional genomics is described based on Brachypodium distachyon, which in the evolution of the Pooideae diverged just prior to the clade of “core pooid” genera that contain the majority of important temperate cereals and forage grasses. Diploid ecotypes of B. distachyon (2n = 10) have five easily distinguishable chromosomes that display high levels of chiasma formation at meiosis. The B. distachyon nuclear genome was indistinguishable in size from that of Arabidopsis, making it the simplest genome described in grasses to date. B. distachyon is a self-fertile, inbreeding annual with a life cycle of less than 4 months. These features, coupled with its small size (approximately 20 cm at maturity), lack of seed-head shatter, and undemanding growth requirements should make it amenable to high-throughput genetics and mutant screens. Immature embryos exhibited a high capacity for plant regeneration via somatic embryogenesis. Regenerated plants display very low levels of albinism and have normal fertility. A simple transformation system has been developed based on microprojectile bombardment of embryogenic callus and hygromycin selection. Selected B. distachyon ecotypes were resistant to all tested cereal-adapted Blumeria graminis species and cereal brown rusts (Puccinia reconditia). In contrast, different ecotypes displayed resistance or disease symptoms following challenge with the rice blast pathogen (Magnaporthe grisea) and wheat/barley yellow stripe rusts (Puccinia striformis). Despite its small stature, B. distachyon has large seeds that should prove useful for studies on grain filling. Such biological characteristics represent important traits for study in temperate cereals. PMID:11743099

The preconception care experiences of women with epilepsy on sodium valproate.

PubMed

Lawther, Lorna; Dolk, Helen; Sinclair, Marlene; Morrow, Jim

2018-05-16

To understand the preconception experiences of women with epilepsy who have been taking the teratogenic drug valproate. Seven women were recruited, three from a preconception clinic and four from an antenatal clinic in a region of the UK. All had taken valproate preconceptionally. Three preconception clinic encounters were observed and audio-recorded. Interviews with all women were analysed using Interpretative Phenomenological Analysis (IPA). Women experienced a "trajectory of balance". Women moved from "maintaining balance" by using valproate to control seizures, to a "shattering of harmony" at the prospect of changing medication and as a result of the physical and mental effects of changing medication, to "restoring balance" which could involve "a new self" due to dramatic changes. Women balanced their health needs with those of their baby, and took responsibility for medication decision-making. They found it difficult to see "who is looking after me" in the healthcare system, either to access preconception care, or to support them through the stress of changing medication. Their journey ended with coming to terms with a variety of experiences: choosing not to have a baby due to unsuccessful change from valproate, recognising that a child from a previous pregnancy had been harmed by valproate or that the current pregnancy might be at risk, or successful medication change in preparation for pregnancy. A clear and adequately funded preconception care pathway is needed from epilepsy diagnosis, including support for stress. Understanding what influences maternalisation may help understand uptake of preconception care. Copyright © 2018 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Slate Islands, Lake Superior, Canada: A mid-size, Complex Impact Structure

NASA Technical Reports Server (NTRS)

Dressler, B. O.; Sharpton, V. L.; Copeland, P.

1999-01-01

The target rocks of the 30-32-km diameter Slate Islands impact structure in northern Lake Superior, Canada, are Archean supracrustal and igneous rocks and supracrustal Proterozoic rocks. Shatter cones, pseudotachylites, impact glasses, and microscopic shock metamorphic features were formed during the contact and compression phase of the impact process, followed, during excavation and central uplift, by polymict, clastic matrix breccias in the uplifted target, and by allogenic fall-back breccias (suevite and bunte breccia). Monomict, autoclastic breccias were mainly observed on Mortimer Island and the other outlying islands of the archipelago and were probably generated relatively late in the impact process (central uplift and/or crater modification). The frequency of low index planar shock metamorphic features in quartz was correlated with results from shock experiments to estimate shock pressures experienced by the target rocks. The resulting shock attenuation plan across the archipelago is irregular, probably because the shock wave did not expand from a point or spherical source, and because of the destruction of an originally more regular shock attenuation plan during the central uplift and crater modification stages of the impact process. No impact melt rock bodies have been positively identified on the islands. An impact melt may be present in the annular trough around the islands, though and-based on a weighted mixture of target rocks-may have an intermediate-mafic composition. No such impact melt was found on the archipelago. An Ar-40-Ar-39 release spectrum of a pseudotachylite provides an age of about 436 Ma for the impact structure, substantiating age constraints based on various stratigraphic considerations.

A review of the risk of contamination of semen and embryos during cryopreservation and measures to limit cross-contamination during banking to prevent disease transmission in ET practices.

PubMed

Bielanski, A

2012-02-01

This review summarizes pertinent data and opinions regarding the potential hazard of disease transmission through cryopreserved and banked embryos in liquid nitrogen (LN). Special attention is given to the survival of pathogens in LN, new vitrification methods, sterility of LN, risks associated with the use of straws and cryovials, and LN dewars including dry shippers. It was experimentally demonstrated that cross-contamination between LN and embryos may occur, when infectious agents are present in LN and embryos are not protected by a sealed container. It is important, therefore, to prevent direct contact of embryos with LN during cryopreservation and their banking. This includes the usage of hermetically sealed, high-quality, shatter-proof freezing containers and/or the application of a secondary enclosure such as "double bagging or straw in straw." A periodic disinfection of cryo-dewars should be considered as an additional precaution to diminish the potential for inadvertent cross-contamination. It might be advisable to use separate LN dewars to quarantine embryos derived from infected donors of valuable genotype or from unknown health status, extinction-threatened species. Nevertheless, in summary, it has been concluded that over 25 yr with no direct evidence of disease transmission by transferred cryopreserved human and animal embryos, that the present cryopreservation technology is sanitary sound, with the stipulation that biocontainment measures recommended by the International Embryo Transfer Society (IETS) and the World Organization for Animal Health - Office International des Epizooties (OIE), are strictly followed. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Little White Lies: Pericarp Color Provides Insights into the Origins and Evolution of Southeast Asian Weedy Rice.

PubMed

Cui, Yongxia; Song, Beng Kah; Li, Lin-Feng; Li, Ya-Ling; Huang, Zhongyun; Caicedo, Ana L; Jia, Yulin; Olsen, Kenneth M

2016-12-07

Weedy rice is a conspecific form of cultivated rice (Oryza sativa L.) that infests rice fields and results in severe crop losses. Weed strains in different world regions appear to have originated multiple times from different domesticated and/or wild rice progenitors. In the case of Malaysian weedy rice, a multiple-origin model has been proposed based on neutral markers and analyses of domestication genes for hull color and seed shattering. Here, we examined variation in pericarp (bran) color and its molecular basis to address how this trait evolved in Malaysian weeds and its possible role in weed adaptation. Functional alleles of the Rc gene confer proanthocyanidin pigmentation of the pericarp, a trait found in most wild and weedy Oryzas and associated with seed dormancy; nonfunctional rc alleles were strongly favored during rice domestication, and most cultivated varieties have nonpigmented pericarps. Phenotypic characterizations of 52 Malaysian weeds revealed that most strains are characterized by the pigmented pericarp; however, some weeds have white pericarps, suggesting close relationships to cultivated rice. Phylogenetic analyses indicate that the Rc haplotypes present in Malaysian weeds likely have at least three distinct origins: wild O. rufipogon, white-pericarp cultivated rice, and red-pericarp cultivated rice. These diverse origins contribute to high Rc nucleotide diversity in the Malaysian weeds. Comparison of Rc allelic distributions with other rice domestication genes suggests that functional Rc alleles may confer particular fitness benefits in weedy rice populations, for example, by conferring seed dormancy. This may promote functional Rc introgression from local wild Oryza populations. Copyright © 2016 Cui et al.

Little White Lies: Pericarp Color Provides Insights into the Origins and Evolution of Southeast Asian Weedy Rice

PubMed Central

Cui, Yongxia; Song, Beng Kah; Li, Lin-Feng; Li, Ya-Ling; Huang, Zhongyun; Caicedo, Ana L.; Jia, Yulin; Olsen, Kenneth M.

2016-01-01

Weedy rice is a conspecific form of cultivated rice (Oryza sativa L.) that infests rice fields and results in severe crop losses. Weed strains in different world regions appear to have originated multiple times from different domesticated and/or wild rice progenitors. In the case of Malaysian weedy rice, a multiple-origin model has been proposed based on neutral markers and analyses of domestication genes for hull color and seed shattering. Here, we examined variation in pericarp (bran) color and its molecular basis to address how this trait evolved in Malaysian weeds and its possible role in weed adaptation. Functional alleles of the Rc gene confer proanthocyanidin pigmentation of the pericarp, a trait found in most wild and weedy Oryzas and associated with seed dormancy; nonfunctional rc alleles were strongly favored during rice domestication, and most cultivated varieties have nonpigmented pericarps. Phenotypic characterizations of 52 Malaysian weeds revealed that most strains are characterized by the pigmented pericarp; however, some weeds have white pericarps, suggesting close relationships to cultivated rice. Phylogenetic analyses indicate that the Rc haplotypes present in Malaysian weeds likely have at least three distinct origins: wild O. rufipogon, white-pericarp cultivated rice, and red-pericarp cultivated rice. These diverse origins contribute to high Rc nucleotide diversity in the Malaysian weeds. Comparison of Rc allelic distributions with other rice domestication genes suggests that functional Rc alleles may confer particular fitness benefits in weedy rice populations, for example, by conferring seed dormancy. This may promote functional Rc introgression from local wild Oryza populations. PMID:27729434

Runaway electrons and ITER

NASA Astrophysics Data System (ADS)

Boozer, Allen H.

2017-05-01

The potential for damage, the magnitude of the extrapolation, and the importance of the atypical—incidents that occur once in a thousand shots—make theory and simulation essential for ensuring that relativistic runaway electrons will not prevent ITER from achieving its mission. Most of the theoretical literature on electron runaway assumes magnetic surfaces exist. ITER planning for the avoidance of halo and runaway currents is focused on massive-gas or shattered-pellet injection of impurities. In simulations of experiments, such injections lead to a rapid large-scale magnetic-surface breakup. Surface breakup, which is a magnetic reconnection, can occur on a quasi-ideal Alfvénic time scale when the resistance is sufficiently small. Nevertheless, the removal of the bulk of the poloidal flux, as in halo-current mitigation, is on a resistive time scale. The acceleration of electrons to relativistic energies requires the confinement of some tubes of magnetic flux within the plasma and a resistive time scale. The interpretation of experiments on existing tokamaks and their extrapolation to ITER should carefully distinguish confined versus unconfined magnetic field lines and quasi-ideal versus resistive evolution. The separation of quasi-ideal from resistive evolution is extremely challenging numerically, but is greatly simplified by constraints of Maxwell’s equations, and in particular those associated with magnetic helicity. The physics of electron runaway along confined magnetic field lines is clarified by relations among the poloidal flux change required for an e-fold in the number of electrons, the energy distribution of the relativistic electrons, and the number of relativistic electron strikes that can be expected in a single disruption event.

Beyond the single gene: How epistasis and gene-by-environment effects influence crop domestication.

PubMed

Doust, Andrew N; Lukens, Lewis; Olsen, Kenneth M; Mauro-Herrera, Margarita; Meyer, Ann; Rogers, Kimberly

2014-04-29

Domestication is a multifaceted evolutionary process, involving changes in individual genes, genetic interactions, and emergent phenotypes. There has been extensive discussion of the phenotypic characteristics of plant domestication, and recent research has started to identify the specific genes and mutational mechanisms that control domestication traits. However, there is an apparent disconnect between the simple genetic architecture described for many crop domestication traits, which should facilitate rapid phenotypic change under selection, and the slow rate of change reported from the archeobotanical record. A possible explanation involves the middle ground between individual genetic changes and their expression during development, where gene-by-gene (epistatic) and gene-by-environment interactions can modify the expression of phenotypes and opportunities for selection. These aspects of genetic architecture have the potential to significantly slow the speed of phenotypic evolution during crop domestication and improvement. Here we examine whether epistatic and gene-by-environment interactions have shaped how domestication traits have evolved. We review available evidence from the literature, and we analyze two domestication-related traits, shattering and flowering time, in a mapping population derived from a cross between domesticated foxtail millet and its wild progenitor. We find that compared with wild progenitor alleles, those favored during domestication often have large phenotypic effects and are relatively insensitive to genetic background and environmental effects. Consistent selection should thus be able to rapidly change traits during domestication. We conclude that if phenotypic evolution was slow during crop domestication, this is more likely due to cultural or historical factors than epistatic or environmental constraints.

The fundamentally different dynamics of dust and gas in molecular clouds

NASA Astrophysics Data System (ADS)

Hopkins, Philip F.; Lee, Hyunseok

2016-03-01

We study the behaviour of large dust grains in turbulent molecular clouds (MCs). In primarily neutral regions, dust grains move as aerodynamic particles, not necessarily with the gas. We therefore directly simulate, for the first time, the behaviour of aerodynamic grains in highly supersonic, magnetohydrodynamic turbulence typical of MCs. We show that, under these conditions, grains with sizes a ≳ 0.01 micron exhibit dramatic (exceeding factor ˜1000) fluctuations in the local dust-to-gas ratio (implying large small-scale variations in abundances, dust cooling rates, and dynamics). The dust can form highly filamentary structures (which would be observed in both dust emission and extinction), which can be much thinner than the characteristic width of gas filaments. Sometimes, the dust and gas filaments are not even in the same location. The `clumping factor' < n_dust2 > / < n_dust > 2 of the dust (critical for dust growth/coagulation/shattering) can reach ˜100, for grains in the ideal size range. The dust clustering is maximized around scales ˜ 0.2 pc (a/μm) (ngas/100 cm- 3)- 1, and is `averaged out' on larger scales. However, because the density varies widely in supersonic turbulence, the dynamic range of scales (and interesting grain sizes) for these fluctuations is much broader than in the subsonic case. Our results are applicable to MCs of essentially all sizes and densities, but we note how Lorentz forces and other physics (neglected here) may change them in some regimes. We discuss the potentially dramatic consequences for star formation, dust growth and destruction, and dust-based observations of MCs.

Cosmological simulation with dust formation and destruction

NASA Astrophysics Data System (ADS)

Aoyama, Shohei; Hou, Kuan-Chou; Hirashita, Hiroyuki; Nagamine, Kentaro; Shimizu, Ikkoh

2018-06-01

To investigate the evolution of dust in a cosmological volume, we perform hydrodynamic simulations, in which the enrichment of metals and dust is treated self-consistently with star formation and stellar feedback. We consider dust evolution driven by dust production in stellar ejecta, dust destruction by sputtering, grain growth by accretion and coagulation, and grain disruption by shattering, and treat small and large grains separately to trace the grain size distribution. After confirming that our model nicely reproduces the observed relation between dust-to-gas ratio and metallicity for nearby galaxies, we concentrate on the dust abundance over the cosmological volume in this paper. The comoving dust mass density has a peak at redshift z ˜ 1-2, coincident with the observationally suggested dustiest epoch in the Universe. In the local Universe, roughly 10 per cent of the dust is contained in the intergalactic medium (IGM), where only 1/3-1/4 of the dust survives against dust destruction by sputtering. We also show that the dust mass function is roughly reproduced at ≲ 108 M⊙, while the massive end still has a discrepancy, which indicates the necessity of stronger feedback in massive galaxies. In addition, our model broadly reproduces the observed radial profile of dust surface density in the circum-galactic medium (CGM). While our model satisfies the observational constraints for the dust extinction on cosmological scales, it predicts that the dust in the CGM and IGM is dominated by large (>0.03 μm) grains, which is in tension with the steep reddening curves observed in the CGM.

Size dependence of the disruption threshold: laboratory examination of millimeter-centimeter porous targets

NASA Astrophysics Data System (ADS)

Nakamura, Akiko M.; Yamane, Fumiya; Okamoto, Takaya; Takasawa, Susumu

2015-03-01

The outcome of collision between small solid bodies is characterized by the threshold energy density Q*s, the specific energy to shatter, that is defined as the ratio of projectile kinetic energy to the target mass (or the sum of target and projectile) needed to produce the largest intact fragment that contains one half the target mass. It is indicated theoretically and by numerical simulations that the disruption threshold Q*s decreases with target size in strength-dominated regime. The tendency was confirmed by laboratory impact experiments using non-porous rock targets (Housen and Holsapple, 1999; Nagaoka et al., 2014). In this study, we performed low-velocity impact disruption experiments on porous gypsum targets with porosity of 65-69% and of three different sizes to examine the size dependence of the disruption threshold for porous material. The gypsum specimens were shown to have a weaker volume dependence on static tensile strength than do the non-porous rocks. The disruption threshold had also a weaker dependence on size scale as Q*s ∝D-γ , γ ≤ 0.25 - 0.26, while the previous laboratory studies showed γ=0.40 for the non-porous rocks. The measurements at low-velocity lead to a value of about 100 J kg-1 for Q*s which is roughly one order of magnitude lower than the value of Q*s for the gypsum targets of 65% porosity but impacted by projectiles with higher velocities. Such a clear dependence on the impact velocity was also shown by previous studies of gypsum targets with porosity of 50%.

Observational evidence for the convective transport of dust over the Central United States

NASA Astrophysics Data System (ADS)

Corr, C. A.; Ziemba, L. D.; Scheuer, E.; Anderson, B. E.; Beyersdorf, A. J.; Chen, G.; Crosbie, E.; Moore, R. H.; Shook, M.; Thornhill, K. L.; Winstead, E.; Lawson, R. P.; Barth, M. C.; Schroeder, J. R.; Blake, D. R.; Dibb, J. E.

2016-02-01

Bulk aerosol composition and aerosol size distributions measured aboard the DC-8 aircraft during the Deep Convective Clouds and Chemistry Experiment mission in May/June 2012 were used to investigate the transport of mineral dust through nine storms encountered over Colorado and Oklahoma. Measurements made at low altitudes (<5 km mean sea level (MSL)) in the storm inflow region were compared to those made in cirrus anvils (altitude > 9 km MSL). Storm mean outflow Ca2+ mass concentrations and total coarse (1 µm < diameter < 5 µm) aerosol volume (Vc) were comparable to mean inflow values as demonstrated by average outflow/inflow ratios greater than 0.5. A positive relationship between Ca2+, Vc, ice water content, and large (diameter > 50 µm) ice particle number concentrations was not evident; thus, the influence of ice shatter on these measurements was assumed small. Mean inflow aerosol number concentrations calculated over a diameter range (0.5 µm < diameter < 5.0 µm) relevant for proxy ice nuclei (NPIN) were ~15-300 times higher than ice particle concentrations for all storms. Ratios of predicted interstitial NPIN (calculated as the difference between inflow NPIN and ice particle concentrations) and inflow NPIN were consistent with those calculated for Ca2+ and Vc and indicated that on average less than 10% of the ingested NPIN were activated as ice nuclei during anvil formation. Deep convection may therefore represent an efficient transport mechanism for dust to the upper troposphere where these particles can function as ice nuclei cirrus forming in situ.

[Recent additions to the biography of the Augsburg physician and Orient traveler Leonhard Rauwolf (1535?-1596)].

PubMed

Herde, Simone; Tilmann, Walter

2010-01-01

The Augsburg physician Leonhard Rauwolf is known to the history of Western sciences for describing the exotic flora of the Near East in his travelogue "Aigentliche Beschreibung der Raiss [...] inn die Morgenländer" (Lauingen 1582). It has been asserted that little is known about his life before and after this journey. This paper summarizes his biography from previous biographical sketches and adds new archival findings from sources at Augsburg and Linz: Leonhard Rauwolf was the son of the Augsburg iron trader and councilman Sixt Rauwolf (1557) and his wife Agatha née Eggelhof (1583). He had several surviving brothers, Hans (or Johann), Georg, Sixt the younger, Matthäus, Ulrich, and a sister, Agatha. Sixt and Leonhard Rauwolf's "middle class" financial situation is analyzed by means of Augsburg tax records. Professional conditions of Leonhard Rauwolf in service of three cities in Germany and Austria are verified from the sources. Four letters, written to colleagues and friends are, along with two of his letters of approbation, edited here for the first time: they illustrate his lasting strong interest in botany and his attempts to build up a professional network. Further his political fate at Augsburg is examined that was shattered by the ongoing of religious conflicts in this biconfessional town and finally caused him to remove to Linz. At last, a look is taken at his later life at Linz and the circumstances of his death which he met in Hungary during the war against the Turks.

Dust Processing in Supernova Remnants: Spitzer MIPS SED and IRS Observations

NASA Technical Reports Server (NTRS)

Hewitt, John W.; Petre, Robert; Katsuda Satoru; Andersen, M.; Rho, J.; Reach, W. T.; Bernard, J. P.

2011-01-01

We present Spitzer MIPS SED and IRS observations of 14 Galactic Supernova Remnants previously identified in the GLIMPSE survey. We find evidence for SNR/molecular cloud interaction through detection of [OI] emission, ionic lines, and emission from molecular hydrogen. Through black-body fitting of the MIPS SEDs we find the large grains to be warm, 29-66 K. The dust emission is modeled using the DUSTEM code and a three component dust model composed of populations of big grains, very small grains, and polycyclic aromatic hydrocarbons. We find the dust to be moderately heated, typically by 30-100 times the interstellar radiation field. The source of the radiation is likely hydrogen recombination, where the excitation of hydrogen occurred in the shock front. The ratio of very small grains to big grains is found for most of the molecular interacting SNRs to be higher than that found in the plane of the Milky Way, typically by a factor of 2--3. We suggest that dust shattering is responsible for the relative over-abundance of small grains, in agreement with prediction from dust destruction models. However, two of the SNRs are best fit with a very low abundance of carbon grains to silicate grains and with a very high radiation field. A likely reason for the low abundance of small carbon grains is sputtering. We find evidence for silicate emission at 20 $\\mu$m in their SEDs, indicating that they are young SNRs based on the strong radiation field necessary to reproduce the observed SEDs.

Geological indicators for impact: The anomalous case of the Vredefort structure, South Africa

NASA Technical Reports Server (NTRS)

Antoine, L. A. G.; Reimold, W. U.

1988-01-01

The Vredefort Dome is located within and almost central to the Witwatersrand basin in its presently known extent. It exposes a central Archean granite core which is surrounded by a collar of supracrustal rocks. These collar rocks outline a strong polygonal geometry. The Archean core is comprised of two concentric zones, the Outer Granite Gneiss (OGG), and the core central Inlandsee Leucogranofels (ILG). The rocks of the inner core display granulite facies metamorphism, while the OGG is in amphibolite facies. The inner core is believed from recent drill hole information to be underlain by mafic and ultramafic gneisses, the extent of which cannot be assessed at present. A fairly broad zone of charnockites separates the OGG and ILG domains. This zone is characterized by a high concentration of pseudotachylite and ductile shearing. Whereas a number of other domical structures are located within or surrounding the Witwatersrand basin, the Vredefort structure is anomalous, in that it has: a partly polygonal geometry; extensive alkali intrusives in the northwestern sector; granophyre dykes (ring-dykes peripheral to the contact collar-basement and NW-SE or NE-SW trending dykes within the Archean basement); contact metamorphism of the collar supracrustal rocks; the overturning of collar supracrustals in the northern sectors; deformation phenomena widely regarded as representing shock metamorphism (pseudotachylite, (sub)planar microdeformation features in quartz, shatter cones and occurrences of high-P quartz polymorphs); a positive 30 mgal gravity anomaly; and high amplitude magnetic anomalies. Recent geophysical, structural and petrological evidence pertinent for the identification of the processes that led to the formation of the Vredefort structure are summarized.

Runaway electrons and ITER

DOE PAGES

Boozer, Allen H.

2017-03-24

The potential for damage, the magnitude of the extrapolation, and the importance of the atypical—incidents that occur once in a thousand shots—make theory and simulation essential for ensuring that relativistic runaway electrons will not prevent ITER from achieving its mission. Most of the theoretical literature on electron runaway assumes magnetic surfaces exist. ITER planning for the avoidance of halo and runaway currents is focused on massive gas or shattered-pellet injection of impurities. In simulations of experiments, such injections lead to a rapid large-scale magnetic-surface breakup. Surface breakup, which is a magnetic reconnection, can occur on a quasi-ideal Alfvénic time scalemore » when the resistance is sufficiently small. Nevertheless, the removal of the bulk of the poloidal flux, as in halo-current mitigation, is on a resistive time scale. The acceleration of electrons to relativistic energies requires the confinement of some tubes of magnetic flux within the plasma and a resistive time scale. The interpretation of experiments on existing tokamaks and their extrapolation to ITER should carefully distinguish confined versus unconfined magnetic field lines and quasi-ideal versus resistive evolution. The separation of quasi-ideal from resistive evolution is extremely challenging numerically, but is greatly simplified by constraints of Maxwell’s equations, and in particular those associated with magnetic helicity. Thus, the physics of electron runaway along confined magnetic field lines is clarified by relations among the poloidal flux change required for an e-fold in the number of electrons, the energy distribution of the relativistic electrons, and the number of relativistic electron strikes that can be expected in a single disruption event.« less

De Sedibus et Causis Morborum: is Essential Tremor a Primary Disease of the Cerebellum?

PubMed

Louis, Elan D

2016-06-01

Morgagni's 1761 publication of De sedibus et causis morborum (i.e., of the Seats and Causes of Diseases) represented a paradigmatic moment in the history of medicine. The book ushered in a new way of conceptualizing human disease, shattering old dogma, and linking constellations of symptoms and signs (i.e., clinical disease) with anatomic pathology in specific organs (i.e., organ disease). This was the anatomical-clinical method, and it attempted to unveil "the seat" of each disease in a specific organ. Essential tremor (ET) is among the most common neurological diseases. There is little debate that the origin of ET lies in the brain, but if one tries to delve more deeply than this, things become murky. The dogma for the past 40 years has been that the seat of ET is the inferior olivary nucleus. Closer scrutiny of this model, however, has revealed its many flaws, and the model, based on little if any empiric evidence, has increasingly lost favor. Arising from a wealth of research in recent years is a growing body of knowledge that links ET to a disarrangement of the cerebellum. Data from a variety of sources reviewed in this issue (clinical, neuroimaging, neurochemical, animal model, physiological, and pathological) link ET to the cerebellum. That the cerebellum is involved in an abnormal brain loop that is responsible for ET is not debated. The tantalizing question is whether an abnormality in the cerebellum is the prime mover, and whether the cerebellum is the seat of this particular disease.

Larkspur (Delphinium spp.) poisoning in livestock.

PubMed

Pfister, J A; Gardner, D R; Panter, K E; Manners, G D; Ralphs, M H; Stegelmeier, B L; Schoch, T K

1999-02-01

Larkspurs (Delphinium spp.) are toxic plants that contain numerous diterpenoid alkaloids which occur as one of two structural types: (1) lycotonine, and (2) 7,8-methylenedioxylycoctonine (MDL-type). Among the lycoctonine type alkaloids are three N-(methylsuccinimido) anthranoyllycoctonine (MSAL-type) alkaloids which appear to be most toxic: methyllycaconitine (MLA), 14-deacetylnudicauline (DAN), and nudicauline. An ester function at C-18 is an important structural requirement for toxicity. Intoxication results from neuromuscular paralysis, as nicotinic acetylcholine receptors in the muscle and brain are blocked by toxic alkaloids. Clinical signs include labored breathing, rapid and irregular heartbeat, muscular weakness, and collapse. Toxic alkaloid concentration generally declines in tall larkspurs with maturation, but alkaloid concentration varies over years and from plant to plant, and is of little use for predicting consumption by cattle. Knowledge of toxic alkaloid concentration is valuable for management purposes when cattle begin to eat larkspur. Cattle generally begin consuming tall larkspur after flowering racemes are elongated, and consumption increases as larkspur matures. Weather is also a major factor in cattle consumption, as cattle tend to eat more larkspur during or just after summer storms. Management options that may be useful for livestock producers include conditioning cattle to avoid larkspur (food aversion learning), grazing tall larkspur ranges before flowering (early grazing) and after seed shatter (late grazing), grazing sheep before cattle, herbicidal control of larkspur plants, and drug therapy for intoxicated animals. Some potentially fruitful research avenues include examining alkaloid chemistry in low and plains larkspurs, developing immunologic methods for analyzing larkspur alkaloids, developing drug therapy, and devising grazing regimes specifically for low and plains larkspur.

Natural and induced endoreic hydrological conditions in the Alta Murgia karstic region (Apulia, Southern Italy)

NASA Astrophysics Data System (ADS)

Canora, F.; Fidelibus, M. D.; Spilotro, G.

2009-04-01

A study aimed at understanding the hydrological processes in karst areas related to the presence of natural and artificial endoreic basins and their modification due to land use change, as well as the influence of above factors on the infiltration rate has been carried out in the Alta Murgia region (Apulia, Southern Italy). The region is a Cretaceous limestone plateau of the Apulian platform, characterized by a mature karstic landscape: due to its elevation, climatic conditions and lithology, the plateau constitutes the main recharge area of the Murgia aquifer. The typical karst topography is essentially related to the subterranean drainage (sinkholes, caves, conduit): surface and subsurface karst geomorphology is strictly interrelated with hydrology. The morphological features of the karstic plateau are defined by the high density of surface karstic forms (mainly dolines), the presence of exposed karst and karren fields, as well as by the extensive outcrop of fractured rocks. Karst surface shows, on the bottom of the morpho-structural depressions called "lame", natural distribution of modest deposits of "terra rossa" and regolith. The "lame" work as streams during and after intense rainfall events, often outlining a primordial ephemeral hydrographical network, frequently convergent towards dolines, poljes or endoreic basins. Alta Murgia shows many natural endoreic basin conditions in a quite flat morphology. In this environment, when intense rainfall events cover large areas and rainfall intensity exceeds the infiltration capacity of soils and/or sinkholes, significant runoff amounts are produced and stored in the basins causing floods. Most of the natural endoreic basins are small and independent: while the majority of them continue functioning as endoreic even in presence of extreme events of high return time, others (quasi-endoreic), under the same circumstances can start contributing to other basins, due to exceeding their water storage capability. This way, very large flow can cascade down towards more depressed areas. Another important feature of the Alta Murgia territory is that the whole area is characterised by a high degree of division into parcels, physically delimited by a well developed network of drystone walls. These have been built during centuries by using stones retrieved from the same fields, having the main role of preserving soils from erosion. The drystone walls that limit the parcels define induced endoreic conditions, where runoff, mostly prevented from discharging out, rather converges toward natural drainage systems and internal depressions, where afterwards infiltrates: the walls allow a high infiltration rate of precipitation of low and medium intensity with low evapotranspiration, while the runoff basically activates only during highest intensity events. The drystone walls have preserved in the time the characteristics of the karst surface, with its high hydraulic conductivity consequent to the negligible outcrop of soils; because of their capability of decreasing the runoff triggering threshold, drystone walls have always worked positively inside the endoreic and quasi-endoreic basins. The above characteristics of both natural and artificial endoreic basins indicate that the definition of the water balance for the Alta Murgia aquifer is complex, requiring a model able to take into account, not only the absorption capacity of the karstic surface textures (which, indeed, are able to delay the start of the runoff due to the need to reach first the saturation of terra rossa in the fissures, pockets and fillings of karst hollows) but also the hydraulic behaviour and geomorphological features of the basins constituting on the whole the recharge area. To make the situation even more complex, in the last decades, the territory was subject to a particular type of land use change, the stone shattering (that is performed by crushing and grinding the karst surface), aimed at making suitable the parcels for mechanized agriculture. While the original situation of Alta Murgia recharge area was able to assure the best conditions for high infiltration rate, not only for the positive role of the drystone walls in holding the soil and slowing down the runoff, but also for the morphological characteristics of the karstic surface textures, stone shattering, by flattening and deeply modifying large part of the original karstic textures and landscape and by demolishing drystone walls, produced severe alteration of the hydrological behaviour of surface and epikarstic textures, increase of runoff and erosion, and substantial geomorphological variations. The land use change thus caused a significant damage to the fragile karstic environment, increasing its vulnerability, and clearly modifying the hydrogeological balance. To assess the impact of endoreic (natural and induced) conditions on the water balance and the significance of the karstic textures modifications, field and laboratory surveys have been carried out for defining at field scale the hydraulic and physical characteristics of the epikarstic textures and their influence respect to the flowing runoff threshold. Such a characterization was mainly aimed at assessing their infiltration capacity. Moreover, detailed geomorphological surveys, in situ investigations, and aerial photo analysis were used to verify the role of the endoreic (natural and induced) conditions, in order to define their control on hydrogeological processes. Simulations of the water balance carried out in a selected part of the recharge area subject to land use change, which originally included natural surface textures and drystone walls. The comparison between the infiltration rate in the natural conditions (by considering the role of natural endoreic basins and a variable retaining capability of induced endoreic conditions created by drystone walls) and that one calculated for the present situation (stone shattered soil with geomorphological variations due to demolition of walls) indicated a significant decrease of the infiltration rate.

What is science good for?

PubMed

Dawkins, R

2001-01-01

A nonbusiness discipline can provide a useful framework for thinking about old problems in new ways. People who study management, for instance, freely borrow from many fields of science to theorize about organizational behavior and business strategy. Evolutionary psychology and biology are especially popular sources of inspiration. But should they be? Evolutionary biologist Richard Dawkins has spent much of his career explaining science to the public. More than 20 years ago, his book The Selfish Gene shattered the popular belief that evolution necessarily favors altruism and self-sacrifice. In a conversation with HBR senior editor Diane Coutu, Dawkins discusses the role of science in our lives and identifies some of the more glaring public misperceptions of scientific theories. In particular, he disentangles the current notion that certain behaviors are in some way preprogrammed and explodes some contemporary myths about the Human Genome Project. Dawkins says much of the popular fear surrounding genetic manipulation is unfounded. "Humans have been practicing it for thousands of years, to no obvious ill effect," he says. Modern foot-long corncobs, the result of more than 1,000 years of artificial selection, are "quite Frankenstein-like" compared to their half-inch-long progenitors, he points out. He also touches on agriculture giant Monsanto and the media: "Part of the reason for Monsanto's troubles is that the company came up against an extraordinary amount of unfortunate, even malevolent, media hype," he says. "And people were more or less misled, by one scare story after another, into stampeding." A staunch defender of science as a haven of rational thought, Dawkins counsels businesspeople to recognize the limitations--as well as the beauty--of science.

Contemporary cosmetic surgery: the potential risks and relevance for practice.

PubMed

Gilmartin, Jo

2011-07-01

To examine and critique the risks of cosmetic surgery and consider implications for practice. Cosmetic surgery is a growing industry with a significant global phenomenon. Feminists have been critical of aesthetic surgery practice, offering a range of representations in regard to 'identity', 'normality', 'cultural and social pressures', 'agency' and 'self-enhancement'. Discourses around minimising risk information acknowledge deficits in not supplying patients with full risk information. The results are usually devastating and lead to serious health complications that incisively diminish well-being for patients and increase health costs. Critical review. This paper represents a critical review of risks associated with cosmetic surgery. A Cumulative Index to Nursing and Allied Health Literature (CINAHL), Medical Literature Analysis and Retrieval System online (Medline) and British Nursing Index (BNI) search with relevant key words were undertaken and selected exemplary articles and research describing and/or evaluating cosmetic surgery risk. Only papers in the English language from 1982-2009 were reviewed. The papers examined were mainly empirical studies; some opinion papers, policy documents, textbooks and websites were examined too. The literature revealed that several factors influence consumer risks including regulation vagaries, medicalisation processes, fear of ageing discrimination, wanting to avoid ethnic prejudice and media pressure. Government strategies in the United Kingdom (UK) have attempted to improve clinical standards; however, little attempt has been made globally to raise institutional and professional awareness of the huge impact of cultural and social pressures on consumers. Avoiding shattering complications by improving the provision of risk information for patients is a worthwhile goal. Therefore, health professionals need to consider consumer rights and autonomy more carefully, facilitate rigorous screening and develop knowledge in regard to relational autonomy and alternative interventions. © 2010 Blackwell Publishing Ltd.

Stellar Winds and Dust Avalanches in the AU Mic Debris Disk

NASA Astrophysics Data System (ADS)

Chiang, Eugene; Fung, Jeffrey

2017-10-01

We explain the fast-moving, ripple-like features in the edge-on debris disk orbiting the young M dwarf AU Mic. The bright features are clouds of submicron dust repelled by the host star’s wind. The clouds are produced by avalanches: radial outflows of dust that gain exponentially more mass as they shatter background disk particles in collisional chain reactions. The avalanches are triggered from a region a few au across—the “avalanche zone”—located on AU Mic’s primary “birth” ring at a true distance of ˜35 au from the star but at a projected distance more than a factor of 10 smaller: the avalanche zone sits directly along the line of sight to the star, on the side of the ring nearest Earth, launching clouds that disk rotation sends wholly to the southeast, as observed. The avalanche zone marks where the primary ring intersects a secondary ring of debris left by the catastrophic disruption of a progenitor up to Varuna in size, less than tens of thousands of years ago. Only where the rings intersect are particle collisions sufficiently violent to spawn the submicron dust needed to seed the avalanches. We show that this picture works quantitatively, reproducing the masses, sizes, and velocities of the observed escaping clouds. The Lorentz force exerted by the wind’s magnetic field, whose polarity reverses periodically according to the stellar magnetic cycle, promises to explain the observed vertical undulations. The timescale between avalanches, about 10 yr, might be set by time variability of the wind mass loss rate or, more speculatively, by some self-regulating limit cycle.

Idealised versus tainted femininity: discourses of the menstrual experience in Australian magazines that target young women.

PubMed

Raftos, M; Jackson, D; Mannix, J

1998-09-01

Information and messages concerning health-related issues are not confined to material provided by official figures or sources. Much information exists in the community and comes from a variety of sources. One such source is the media. This paper reports the findings of a study conducted over a 12-month period of advertisements for menstrual products in a selection of four monthly Australian magazines (n = 48) directed towards young women. The study examined the way in which menstruation and the menstrual experience were depicted in terms of page space, textual content and visual images. Findings revealed that advertisements for menstrual products provided confusing, conflicting and paradoxical messages. These included stressing the normality of menstruation while also emphasising the importance of keeping it hidden and secret. Menstruation was depicted as being a state of tainted (idealised) femininity because of the potential for the menstrual silence to be shattered by people finding out. Protection failure was depicted as being the ultimate in tainted femininity and a result of a woman's incorrect choice of product. Choosing menstrual-care products was depicted as simple but, paradoxically, complex and confusing. Women were depicted as liberated and sophisticated but images and language related to infancy were used. Freedom and liberation were conferred by the use of the advertised product. Overall, in common with previous studies, menstruation was depicted as a crisis of hygiene that is a risk to femininity. Advertisements for pantyliners suggest that femininity itself poses a threat to (idealised) femininity. This study demonstrates the crucial role of the media as a source of health information for young women.

The rheological behaviour of fracture-filling cherts: example of Barite Valley dikes, Barberton Greenstone Belt, South Africa

NASA Astrophysics Data System (ADS)

Ledevin, M.; Arndt, N.; Davaille, A.; Ledevin, R.; Simionovici, A.

2015-02-01

In the Barberton Greenstone Belt, South Africa, a 100-250 m thick complex of carbonaceous chert dikes marks the transition from the Mendon Formation to the Mapepe Formation (3260 Ma). The sub-vertical- to vertical position of the fractures, the abundance of highly shattered zones with poorly rotated angular fragments and common jigsaw fit, radial structures, and multiple injection features point to repetitive hydraulic fracturing that released overpressured fluids trapped within the shallow crust. The chemical and isotopic compositions of the chert favour a model whereby seawater-derived fluids circulated at low temperature (< 100-150 °C) within the shallow crust. From the microscopic structure of the chert, the injected material was a slurry of abundant clay-sized, rounded particles of silica, carbonaceous matter and minor clay minerals, all suspended in a siliceous colloidal solution. The dike geometry and characteristics of the slurry concur on that the chert was viscoelastic, and most probably thixotropic at the time of injection: the penetration of black chert into extremely fine fractures is evidence for low viscosity at the time of injection and the suspension of large country rock fragments in the chert matrix provides evidence of high viscosity soon thereafter. We explain the rheology by the particulate and colloidal structure of the slurry, and by the characteristic of silica suspensions to form cohesive 3-D networks through gelation. Our results provide valuable information about the compositions, physical characteristics and rheological properties of the fluids that circulated through Archean volcano-sedimentary sequences, which is an additional step to understand conditions on the floor of Archean oceans, the habitat of early life.

2013 R&D 100 Award: 'SHIELD' protects NIF optics from harmful pulses

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

Chou, Jason

In the past, it took as long as 12 hours to manually screen 48 critical checkpoints at the National Ignition Facility (NIF) for harmful laser pulses. The screening equipment had to be moved from point to point throughout a facility the size of three football fields. Now with a new technology, called Laser SHIELD (Screening at High-throughput to Identify Energetic Laser Distortion), and with the push of a button, the screening can be done in less than one second. Proper screening of pulses is critical for the operation of high-energy lasers to ensure that the laser does not exceed safemore » operating conditions for optics. The energetic beams of light are so powerful that, when left uncontrolled, they can shatter the extremely valuable glass inside the laser. If a harmful pulse is found, immediate adjustments can be made in order to protect the optics for the facility. Laser SHIELD is a custom-designed high-throughput screening system built from low-cost and commercially available components found in the telecommunications industry. Its all-fiber design makes it amenable to the unique needs of high-energy laser facilities, including routing to intricate pick-off locations, immunity to electromagnetic interference and low-loss transport (up to several kilometers). The technology offers several important benefits for NIF. First, the facility is able to fire more shots in less time-an efficiency that saves the facility millions of dollars each year. Second, high-energy lasers are more flexible to wavelength changes requested by target physicists. Third, by identifying harmful pulses before they damage the laser's optics, the facility potentially saves hundreds of thousands of dollars in maintenance costs each year.« less

shinyheatmap: Ultra fast low memory heatmap web interface for big data genomics.

PubMed

Khomtchouk, Bohdan B; Hennessy, James R; Wahlestedt, Claes

2017-01-01

Transcriptomics, metabolomics, metagenomics, and other various next-generation sequencing (-omics) fields are known for their production of large datasets, especially across single-cell sequencing studies. Visualizing such big data has posed technical challenges in biology, both in terms of available computational resources as well as programming acumen. Since heatmaps are used to depict high-dimensional numerical data as a colored grid of cells, efficiency and speed have often proven to be critical considerations in the process of successfully converting data into graphics. For example, rendering interactive heatmaps from large input datasets (e.g., 100k+ rows) has been computationally infeasible on both desktop computers and web browsers. In addition to memory requirements, programming skills and knowledge have frequently been barriers-to-entry for creating highly customizable heatmaps. We propose shinyheatmap: an advanced user-friendly heatmap software suite capable of efficiently creating highly customizable static and interactive biological heatmaps in a web browser. shinyheatmap is a low memory footprint program, making it particularly well-suited for the interactive visualization of extremely large datasets that cannot typically be computed in-memory due to size restrictions. Also, shinyheatmap features a built-in high performance web plug-in, fastheatmap, for rapidly plotting interactive heatmaps of datasets as large as 105-107 rows within seconds, effectively shattering previous performance benchmarks of heatmap rendering speed. shinyheatmap is hosted online as a freely available web server with an intuitive graphical user interface: http://shinyheatmap.com. The methods are implemented in R, and are available as part of the shinyheatmap project at: https://github.com/Bohdan-Khomtchouk/shinyheatmap. Users can access fastheatmap directly from within the shinyheatmap web interface, and all source code has been made publicly available on Github: https://github.com/Bohdan-Khomtchouk/fastheatmap.

The genesis of neurosurgery and the evolution of the neurosurgical operative environment: part II--concepts for future development, 2003 and beyond.

PubMed

Liu, Charles Y; Spicer, Mark; Apuzzo, Michael L J

2003-01-01

The future development of the neurosurgical operative environment is driven principally by concurrent development in science and technology. In the new millennium, these developments are taking on a Jules Verne quality, with the ability to construct and manipulate the human organism and its surroundings at the level of atoms and molecules seemingly at hand. Thus, an examination of currents in technology advancement from the neurosurgical perspective can provide insight into the evolution of the neurosurgical operative environment. In the future, the optimal design solution for the operative environment requirements of specialized neurosurgery may take the form of composites of venues that are currently mutually distinct. Advances in microfabrication technology and laser optical manipulators are expanding the scope and role of robotics, with novel opportunities for bionic integration. Assimilation of biosensor technology into the operative environment promises to provide neurosurgeons of the future with a vastly expanded set of physiological data, which will require concurrent simplification and optimization of analysis and presentation schemes to facilitate practical usefulness. Nanotechnology derivatives are shattering the maximum limits of resolution and magnification allowed by conventional microscopes. Furthermore, quantum computing and molecular electronics promise to greatly enhance computational power, allowing the emerging reality of simulation and virtual neurosurgery for rehearsal and training purposes. Progressive minimalism is evident throughout, leading ultimately to a paradigm shift as the nanoscale is approached. At the interface between the old and new technological paradigms, issues related to integration may dictate the ultimate emergence of the products of the new paradigm. Once initiated, however, history suggests that the process of change will proceed rapidly and dramatically, with the ultimate neurosurgical operative environment of the future being far more complex in functional capacity but strikingly simple in apparent form.

Exposure to genocide and risk of suicide in Rwanda: a population-based case-control study.

PubMed

Rubanzana, Wilson; Hedt-Gauthier, Bethany L; Ntaganira, Joseph; Freeman, Michael D

2015-02-01

In Rwanda, an estimated one million people were killed during the 1994 genocide, leaving the country shattered and social fabric destroyed. Large-scale traumatic events such as wars and genocides have been linked to endemic post-traumatic stress disorder, depression and suicidality. The study objective was to investigate whether the 1994 genocide exposure is associated with suicide in Rwanda. We conducted a population-based case-control study. Suicide victims were matched to three living controls for sex, age and residential location. Exposure was defined as being a genocide survivor, having suffered physical/sexual abuse in the genocide, losing a first-degree relative in the genocide, having been convicted for genocide crimes or having a first-degree relative convicted for genocide. From May 2011 to May 2013, 162 cases and 486 controls were enrolled countrywide. Information was collected from the police, local village administrators and family members. After adjusting for potential confounders, having been convicted for genocide crimes was a significant predictor for suicide (OR=17.3, 95% CI 3.4 to 88.1). Being a survivor, having been physically or sexually abused during the genocide, and having lost a first-degree family member to genocide were not significantly associated with suicide. These findings demonstrate that individuals convicted for genocide crimes are experiencing continued psychological disturbances that affect their social reintegration into the community even 20 years after the event. Given the large number of genocide perpetrators reintegrated after criminal courts and Gacaca traditional reconciling trials, suicide could become a serious public health burden if preventive remedial action is not identified. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Deep RNA-Seq to unlock the gene bank of floral development in Sinapis arvensis.

PubMed

Liu, Jia; Mei, Desheng; Li, Yunchang; Huang, Shunmou; Hu, Qiong

2014-01-01

Sinapis arvensis is a weed with strong biological activity. Despite being a problematic annual weed that contaminates agricultural crop yield, it is a valuable alien germplasm resource. It can be utilized for broadening the genetic background of Brassica crops with desirable agricultural traits like resistance to blackleg (Leptosphaeria maculans), stem rot (Sclerotinia sclerotium) and pod shatter (caused by FRUITFULL gene). However, few genetic studies of S. arvensis were reported because of the lack of genomic resources. In the present study, we performed de novo transcriptome sequencing to produce a comprehensive dataset for S. arvensis for the first time. We used Illumina paired-end sequencing technology to sequence the S. arvensis flower transcriptome and generated 40,981,443 reads that were assembled into 131,278 transcripts. We de novo assembled 96,562 high quality unigenes with an average length of 832 bp. A total of 33,662 full-length ORF complete sequences were identified, and 41,415 unigenes were mapped onto 128 pathways using the KEGG Pathway database. The annotated unigenes were compared against Brassica rapa, B. oleracea, B. napus and Arabidopsis thaliana. Among these unigenes, 76,324 were identified as putative homologs of annotated sequences in the public protein databases, of which 1194 were associated with plant hormone signal transduction and 113 were related to gibberellin homeostasis/signaling. Unigenes that did not match any of those sequence datasets were considered to be unique to S. arvensis. Furthermore, 21,321 simple sequence repeats were found. Our study will enhance the currently available resources for Brassicaceae and will provide a platform for future genomic studies for genetic improvement of Brassica crops.

Comparing Results of SPH/N-body Impact Simulations Using Both Solid and Rubble-pile Target Asteroids

NASA Astrophysics Data System (ADS)

Durda, Daniel D.; Bottke, W. F.; Enke, B. L.; Nesvorný, D.; Asphaug, E.; Richardson, D. C.

2006-09-01

We have been investigating the properties of satellites and the morphology of size-frequency distributions (SFDs) resulting from a suite of 160 SPH/N-body simulations of impacts into 100-km diameter parent asteroids (Durda et al. 2004, Icarus 170, 243-257; Durda et al. 2006, Icarus, in press). These simulations have produced many valuable insights into the outcomes of cratering and disruptive impacts but were limited to monolithic basalt targets. As a natural consequence of collisional evolution, however, many asteroids have undergone a series of battering impacts that likely have left their interiors substantially fractured, if not completely rubblized. In light of this, we have re-mapped the matrix of simulations using rubble-pile target objects. We constructed the rubble-pile targets by filling the interior of the 100-km diameter spherical shell (the target envelope) with randomly sized solid spheres in mutual contact. We then assigned full damage (which reduces tensile and shear stresses to zero) to SPH particles in the contacts between the components; the remaining volume is void space. The internal spherical components have a power-law distribution of sizes simulating fragments of a pre-shattered parent object. First-look analysis of the rubble-pile results indicate some general similarities to the simulations with the monolithic targets (e.g., similar trends in the number of small, gravitationally bound satellite systems as a function of impact conditions) and some significant differences (e.g., size of largest remnants and smaller debris affecting size frequency distributions of resulting families). We will report details of a more thorough analysis and the implications for collisional models of the main asteroid belt. This work is supported by the National Science Foundation, grant number AST0407045.

Reproductive traits and evolutionary divergence between Mediterranean crops and their wild relatives.

PubMed

Iriondo, J M; Milla, R; Volis, S; Rubio de Casas, R

2018-01-01

Changes in reproductive traits associated with domestication critically determine the evolutionary divergence between crops and their wild relatives, as well as the potential of crop plants to become feral. In this review, we examine the genetic mechanisms of plant domestication and the different types of selection involved, and describe the particularities of domestication of Mediterranean field crops with regard to their reproductive traits, showing illustrative examples. We also explore gene flow patterns between Mediterranean field crops and their wild relatives, along with their ecological, evolutionary and economic implications. Domestication entails multiple selective processes, including direct selection, environmental adaptation and developmental constraints. In contrast to clonal propagation in perennials, sexual reproduction and seed propagation in annuals and biennials have led to a distinct pathway of evolution of reproductive traits. Thus, the initial domestication and further breeding of Mediterranean field crops has brought about changes in reproductive traits, such as higher mean values and variance of seed and fruit sizes, reduced fruit and seed toxicity, non-shattering seeds and loss of seed dormancy. Evolution under domestication is not a linear process, and bi-directional gene flow between wild and crop taxa is a frequent phenomenon. Thus, hybridisation and introgression have played a very important role in determining the genetics of current cultivars. In turn, gene flow from crops to wild relatives can lead to introgression of crop genes into wild populations and potentially alter the characteristics of natural communities. In conclusion, plant evolution under domestication has not only changed the reproductive biology of cultivated taxa, its effects are multifaceted and have implications beyond agriculture. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

MULTIBAND OPTICAL OBSERVATION OF THE P/2010 A2 DUST TAIL

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

Kim, Junhan; Ishiguro, Masateru; Hanayama, Hidekazu

2012-02-10

An inner main-belt asteroid, P/2010 A2, was discovered on 2010 January 6. Based on its orbital elements, it is considered that the asteroid belongs to the Flora collisional family, where S-type asteroids are common, while showing a comet-like dust tail. Although analysis of images taken by the Hubble Space Telescope and Rosetta spacecraft suggested that the dust tail resulted from a recent head-on collision between asteroids, an alternative idea of ice sublimation was suggested based on the morphological fitting of ground-based images. Here, we report a multiband observation of P/2010 A2 made on 2010 January with a 105 cm telescopemore » at the Ishigakijima Astronomical Observatory. Three broadband filters, g', R{sub c} , and I{sub c} , were employed for the observation. The unique multiband data reveal that the reflectance spectrum of the P/2010 A2 dust tail resembles that of an Sq-type asteroid or that of ordinary chondrites rather than that of an S-type asteroid. Due to the large error of the measurement, the reflectance spectrum also resembles the spectra of C-type asteroids, even though C-type asteroids are uncommon in the Flora family. The reflectances relative to the g' band (470 nm) are 1.096 {+-} 0.046 at the R{sub c} band (650 nm) and 1.131 {+-} 0.061 at the I{sub c} band (800 nm). We hypothesize that the parent body of P/2010 A2 was originally S-type but was then shattered upon collision into scattering fresh chondritic particles from the interior, thus forming the dust tail.« less

Glass formation and unusual hygroscopic growth of iodic acid solution droplets with relevance for iodine oxide particles in the coastal marine boundary layer

NASA Astrophysics Data System (ADS)

Murray, B. J.; Haddrell, A. E.; Peppe, S.; Davies, J. F.; Reid, J. P.; O'Sullivan, D.; Price, H. C.; Kumar, R.; Saunders, R. W.; Plane, J. M. C.; Umo, N. S.; Wilson, T. W.

2012-03-01

Iodine oxide particles are known to nucleate in the marine boundary layer where gas phase molecular iodine and organoiodine species are produced by macroalgae. There has been some debate over the chemical identity of these particles. Hygroscopic measurements have been used to infer that they are composed of insoluble I2O4, while elemental analysis of laboratory generated particles suggests soluble I2O5 or its hydrated form iodic acid, HIO3 (I2O5 · H2O). In this paper we explore the response of super-micron sized aqueous iodic acid solution droplets to varying humidity using both Raman microscopy and single particle electrodynamic traps. These measurements reveal that the propensity of an iodic acid solution droplet to crystallise is negligible on drying to ~0% relative humidity (RH). On applying mechanical pressure to these droplets they shatter in a manner consistent with an ultra-viscous liquid or a brittle glass, but subsequent water uptake between 10 and 20% RH causes their viscosity to reduce sufficiently that the cracked droplets flow and merge. The persistence of iodic acid solution in an amorphous state, rather than a crystalline state, suggests they will more readily accommodate other condensable material and are therefore more likely to grow to sizes where they may serve as cloud condensation nuclei. On increasing the humidity to ~90% the mass of the droplets only increases by ~20% with a corresponding increase in radius of only ~6 %, which is remarkably small for a highly soluble material. We suggest that the small growth factor of aqueous iodic acid solution droplets is consistent with the small aerosol growth factors observed in field experiments.