Dynamic patterns of cortical expansion during folding of the preterm human brain.

PubMed

Garcia, Kara E; Robinson, Emma C; Alexopoulos, Dimitrios; Dierker, Donna L; Glasser, Matthew F; Coalson, Timothy S; Ortinau, Cynthia M; Rueckert, Daniel; Taber, Larry A; Van Essen, David C; Rogers, Cynthia E; Smyser, Christopher D; Bayly, Philip V

2018-03-20

During the third trimester of human brain development, the cerebral cortex undergoes dramatic surface expansion and folding. Physical models suggest that relatively rapid growth of the cortical gray matter helps drive this folding, and structural data suggest that growth may vary in both space (by region on the cortical surface) and time. In this study, we propose a unique method to estimate local growth from sequential cortical reconstructions. Using anatomically constrained multimodal surface matching (aMSM), we obtain accurate, physically guided point correspondence between younger and older cortical reconstructions of the same individual. From each pair of surfaces, we calculate continuous, smooth maps of cortical expansion with unprecedented precision. By considering 30 preterm infants scanned two to four times during the period of rapid cortical expansion (28-38 wk postmenstrual age), we observe significant regional differences in growth across the cortical surface that are consistent with the emergence of new folds. Furthermore, these growth patterns shift over the course of development, with noninjured subjects following a highly consistent trajectory. This information provides a detailed picture of dynamic changes in cortical growth, connecting what is known about patterns of development at the microscopic (cellular) and macroscopic (folding) scales. Since our method provides specific growth maps for individual brains, we are also able to detect alterations due to injury. This fully automated surface analysis, based on tools freely available to the brain-mapping community, may also serve as a useful approach for future studies of abnormal growth due to genetic disorders, injury, or other environmental variables.

Statistical Enrichment of Epigenetic States Around Triplet Repeats that Can Undergo Expansions

PubMed Central

Essebier, Alexandra; Vera Wolf, Patricia; Cao, Minh Duc; Carroll, Bernard J.; Balasubramanian, Sureshkumar; Bodén, Mikael

2016-01-01

More than 30 human genetic diseases are linked to tri-nucleotide repeat expansions. There is no known mechanism that explains repeat expansions in full, but changes in the epigenetic state of the associated locus has been implicated in the disease pathology for a growing number of examples. A comprehensive comparative analysis of the genomic features associated with diverse repeat expansions has been lacking. Here, in an effort to decipher the propensity of repeats to undergo expansion and result in a disease state, we determine the genomic coordinates of tri-nucleotide repeat tracts at base pair resolution and computationally establish epigenetic profiles around them. Using three complementary statistical tests, we reveal that several epigenetic states are enriched around repeats that are associated with disease, even in cells that do not harbor expansion, relative to a carefully stratified background. Analysis of over one hundred cell types reveals that epigenetic states generally tend to vary widely between genic regions and cell types. However, there is qualified consistency in the epigenetic signatures of repeats associated with disease suggesting that changes to the chromatin and the DNA around an expanding repeat locus are likely to be similar. These epigenetic signatures may be exploited further to develop models that could explain the propensity of repeats to undergo expansions. PMID:27013954

Dimensional changes of upper airway after rapid maxillary expansion: a prospective cone-beam computed tomography study.

PubMed

Chang, Yoon; Koenig, Lisa J; Pruszynski, Jessica E; Bradley, Thomas G; Bosio, Jose A; Liu, Dawei

2013-04-01

The aim of this prospective study was to use cone-beam computed tomography to assess the dimensional changes of the upper airway in orthodontic patients with maxillary constriction treated by rapid maxillary expansion. Fourteen orthodontic patients (mean age, 12.9 years; range, 9.7-16 years) were recruited. The patients with posterior crossbite and constricted maxilla were treated with rapid maxillary expansion as the initial part of their comprehensive orthodontic treatments. Before and after rapid maxillary expansion cone-beam computed tomography scans were taken to measure the retropalatal and retroglossal airway changes in terms of volume, and sagittal and cross-sectional areas. The transverse expansions by rapid maxillary expansion were assessed between the midlingual alveolar bone plates at the maxillary first molar and first premolar levels. The measurements of the before and after rapid maxillary expansion scans were compared by using paired t tests with the Bonferroni adjustment for multiple comparisons. After rapid maxillary expansion, significant and equal amounts of 4.8 mm of expansion were observed at the first molar (P = 0.0000) and the first premolar (P = 0.0000) levels. The width increase at the first premolar level (20.0%) was significantly greater than that at the first molar level (15.0%) (P = 0.035). As the primary outcome variable, the cross-sectional airway measured from the posterior nasal spine to basion level was the only parameter showing a significant increase of 99.4 mm(2) (59.6%) after rapid maxillary expansion (P = 0.0004). These results confirm the findings of previous studies of the effect of rapid maxillary expansion on the maxilla. Additionally, we found that only the cross-sectional area of the upper airway at the posterior nasal spine to basion level significantly gains a moderate increase after rapid maxillary expansion. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Patterns of coordinated cortical remodeling during adolescence and their associations with functional specialization and evolutionary expansion.

PubMed

Sotiras, Aristeidis; Toledo, Jon B; Gur, Raquel E; Gur, Ruben C; Satterthwaite, Theodore D; Davatzikos, Christos

2017-03-28

During adolescence, the human cortex undergoes substantial remodeling to support a rapid expansion of behavioral repertoire. Accurately quantifying these changes is a prerequisite for understanding normal brain development, as well as the neuropsychiatric disorders that emerge in this vulnerable period. Past accounts have demonstrated substantial regional heterogeneity in patterns of brain development, but frequently have been limited by small samples and analytics that do not evaluate complex multivariate imaging patterns. Capitalizing on recent advances in multivariate analysis methods, we used nonnegative matrix factorization (NMF) to uncover coordinated patterns of cortical development in a sample of 934 youths ages 8-20, who completed structural neuroimaging as part of the Philadelphia Neurodevelopmental Cohort. Patterns of structural covariance (PSCs) derived by NMF were highly reproducible over a range of resolutions, and differed markedly from common gyral-based structural atlases. Moreover, PSCs were largely symmetric and showed correspondence to specific large-scale functional networks. The level of correspondence was ordered according to their functional role and position in the evolutionary hierarchy, being high in lower-order visual and somatomotor networks and diminishing in higher-order association cortex. Furthermore, PSCs showed divergent developmental associations, with PSCs in higher-order association cortex networks showing greater changes with age than primary somatomotor and visual networks. Critically, such developmental changes within PSCs were significantly associated with the degree of evolutionary cortical expansion. Together, our findings delineate a set of structural brain networks that undergo coordinated cortical thinning during adolescence, which is in part governed by evolutionary novelty and functional specialization.

Spatiotemporal Changes of Built-Up Land Expansion and Carbon Emissions Caused by the Chinese Construction Industry.

PubMed

Chuai, Xiaowei; Huang, Xianjin; Lu, Qinli; Zhang, Mei; Zhao, Rongqin; Lu, Junyu

2015-11-03

China is undergoing rapid urbanization, enlarging the construction industry, greatly expanding built-up land, and generating substantial carbon emissions. We calculated both the direct and indirect carbon emissions from energy consumption (anthropogenic emissions) in the construction sector and analyzed built-up land expansion and carbon storage losses from the terrestrial ecosystem. According to our study, the total anthropogenic carbon emissions from the construction sector increased from 3,905×10(4) to 103,721.17×10(4) t from 1995 to 2010, representing 27.87%-34.31% of the total carbon emissions from energy consumption in China. Indirect carbon emissions from other industrial sectors induced by the construction sector represented approximately 97% of the total anthropogenic carbon emissions of the sector. These emissions were mainly concentrated in seven upstream industry sectors. Based on our assumptions, built-up land expansion caused 3704.84×10(4) t of carbon storage loss from vegetation between 1995 and 2010. Cropland was the main built-up land expansion type across all regions. The study shows great regional differences. Coastal regions showed dramatic built-up land expansion, greater carbon storage losses from vegetation, and greater anthropogenic carbon emissions. These regional differences were the most obvious in East China followed by Midsouth China. These regions are under pressure for strong carbon emissions reduction.

The Role of Retrotransposons in Gene Family Expansions in the Human and Mouse Genomes

PubMed Central

Janoušek, Václav; Laukaitis, Christina M.; Yanchukov, Alexey

2016-01-01

Abstract Retrotransposons comprise a large portion of mammalian genomes. They contribute to structural changes and more importantly to gene regulation. The expansion and diversification of gene families have been implicated as sources of evolutionary novelties. Given the roles retrotransposons play in genomes, their contribution to the evolution of gene families warrants further exploration. In this study, we found a significant association between two major retrotransposon classes, LINEs and LTRs, and lineage-specific gene family expansions in both the human and mouse genomes. The distribution and diversity differ between LINEs and LTRs, suggesting that each has a distinct involvement in gene family expansion. LTRs are associated with open chromatin sites surrounding the gene families, supporting their involvement in gene regulation, whereas LINEs may play a structural role promoting gene duplication. Our findings also suggest that gene family expansions, especially in the mouse genome, undergo two phases. The first phase is characterized by elevated deposition of LTRs and their utilization in reshaping gene regulatory networks. The second phase is characterized by rapid gene family expansion due to continuous accumulation of LINEs and it appears that, in some instances at least, this could become a runaway process. We provide an example in which this has happened and we present a simulation supporting the possibility of the runaway process. Altogether we provide evidence of the contribution of retrotransposons to the expansion and evolution of gene families. Our findings emphasize the putative importance of these elements in diversification and adaptation in the human and mouse lineages. PMID:27503295

Dynamic structure of confined shocks undergoing sudden expansion

NASA Astrophysics Data System (ADS)

Abate, G.; Shyy, W.

2002-01-01

The gas dynamic phenomenon associated with a normal shock wave within a tube undergoing a sudden area expansion consists of highly transient flow and diffraction that give rise to turbulent, compressible, vortical flows. These interactions can occur at time scales typically ranging from micro- to milliseconds. In this article, we review recent experimental and numerical results to highlight the flow phenomena and main physical mechanisms associated with this geometry. The topics addressed include time-accurate shock and vortex locations, flowfield evolution and structure, wall-shock Mach number, two- vs. three-dimensional sudden expansions, and the effect of viscous dissipation on planar shock-front expansions. Between axisymmetric and planar geometries, the flow structure evolves very similarly early on in the sudden expansion process (i.e., within the first two shock tube diameters). Both numerical and experimental studies confirm that the trajectory of the vortex formed at the expansion corner is convected into the flowfield faster in the axisymmetric case than the planar case. The lateral propagation of the vortices correlates very well between axisymmetric and planar geometries. In regard to the rate of dissipation of turbulent kinetic energy (TKE) for a two-dimensional planar shock undergoing a sudden expansion within a confined chamber, calculations show that the solenoidal dissipation is confined to the region of high strain rates arising from the expansion corner. Furthermore, the dilatational dissipation is concentrated mainly at the curvature of the incident, reflected, and barrel shock fronts. The multiple physical mechanisms identified, including shock-strain rate interaction, baroclinic effect, vorticity generation, and different aspects of viscous dissipation, have produced individual and collective flow structures observed experimentally.

Reevaluating Suitability Estimates Based on Dynamics of Cropland Expansion in the Brazilian Amazon

NASA Technical Reports Server (NTRS)

Morton, Douglas C.; Noojipady, Praveen; Macedo, Marcia M.; Victoria, Daniel C.; Bolfe, Edson L.

2016-01-01

Agricultural suitability maps are a key input for land use zoning and projections of cropland expansion. Suitability assessments typically consider edaphic conditions, climate, crop characteristics, and sometimes incorporate accessibility to transportation and market infrastructure. However, correct weighting among these disparate factors is challenging, given rapid development of new crop varieties, irrigation, and road networks, as well as changing global demand for agricultural commodities. Here, we compared three independent assessments of cropland suitability to spatial and temporal dynamics of agricultural expansion in the Brazilian state of Mato Grosso during 2001 2012. We found that areas of recent cropland expansion identified using satellite data were generally designated as low to moderate suitability for rainfed crop production. Our analysis highlighted the abrupt nature of suitability boundaries, rather than smooth gradients of agricultural potential, with little additional cropland expansion beyond the extent of the flattest areas (0-2% slope). Satellite-based estimates of the interannual variability in the use of existing crop areas also provided an alternate means to assess suitability. On average, cropland areas in the Cerrado biome had higher utilization (84%) than croplands in the Amazon region of northern Mato Grosso (74%). Areas of more recent expansion had lower utilization than croplands established before 2002, providing empirical evidence for lower suitability or alternative management strategies (e.g., pasture soya rotations) for lands undergoing more recent land use transitions. This unplanted reserve constitutes a large area of potentially available cropland (PAC)without further expansion, within the management limits imposed for pest management and fallow cycles. Using two key constraints on future cropland expansion, slope and restrictions on further deforestation of Amazon or Cerrado vegetation, we found little available flat land for further legal expansion of crop production in Mato Grosso. Dynamics of cropland expansion from more than a decade of satellite observations indicated narrow ranges of suitability criteria, restricting PAC under current policy conditions, and emphasizing the advantages of field-scale information to assess suitability and utilization.

Pain and Anxiety Levels of Patients Undergoing Tissue Expansion After Mastectomies: A Case Series Study.

PubMed

Le, Nicole K; García-Molina, Carla; Kumar, Ambuj; Griffin, Lisa; Dayicioglu, Deniz

2017-01-01

The tissue expansion process is done after mastectomies to increase the submuscular space in preparation for the placement of permanent breast implant. The process is often believed to be painful by patients who are often intimidated by the prospect of mechanically stretching out their skin and muscle. This study aims to quantify the pain experienced by patients and determine the different pain management techniques used. We used a case series approach, in which patients who were undergoing serial tissue expansion process were asked to rate their pain and anxiety on a scale from 1 to 10, using a questionnaire and the visual analog scale. Pain was rated during and after the expansion procedure, and patients were also surveyed to find the most commonly used and most effective pain management technique. Patients typically reported very little pain during and after the procedure, with an average of 0.4 to 2.5 pain experienced out of 10. The pain did not last, on average, longer than 1 day. Furthermore, the most widely used and most helpful pain medication was ibuprofen. During the tissue expansion procedure, the mean anxiety level was 0.64 (1.3). The findings show that tissue expansion process is a relatively low pain procedure and is not a contraindication for undergoing breast reconstruction. Ibuprofen, a mild treatment with few side effects, was efficacious in pain relief though most patients required no pain relief.

Surgically assisted rapid palatal expansion. An acoustic rhinometric, morphometric and sonographic investigation.

PubMed

Wriedt, S; Kunkel, M; Zentner, A; Wahlmann, U W

2001-03-01

This study aimed to evaluate the effect of surgically assisted rapid palatal expansion on the skeletal structures of the midface. Ten patients (mean age 28.5 years) were investigated by means of acoustic rhinometry, study model analysis and sonography before and after the procedure of surgically assisted rapid palatal expansion. The measurements revealed that surgically assisted rapid palatal expansion not only resulted in transverse expansion of the maxilla, providing dental arch space for lining up the teeth; the procedure also caused a substantial enlargement of the maxillary apical base and of the palatal vault, providing space for the tongue for correct swallowing and thus preventing relapse. There was a distinct subjective improvement in nasal breathing associated with enlargement of the nasal valve towards normal values and with an increase of nasal volume in all compartments. The measurements showed a marked influence of surgically assisted rapid palatal expansion on the skeletal structures of the midface. The significant widening can be demonstrated by non-invasive examination. Success of the osteotomy procedure can be readily monitored by sonographic examination of the expansion and the subsequent ossification, which allows individually adjusted retention periods and avoids frequent radiation exposure.

Transverse Expansion and Stability after Segmental Le Fort I Osteotomy versus Surgically Assisted Rapid Maxillary Expansion: a Systematic Review

PubMed Central

Blæhr, Tue Lindberg

2016-01-01

ABSTRACT Objectives The objective of the present systematic review was to test the hypothesis of no difference in transverse skeletal and dental arch expansion and relapse after segmental Le Fort I osteotomy versus surgically assisted rapid maxillary expansion. Material and Methods A MEDLINE (PubMed), Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted by including human studies published in English from January 1, 2000 to June 1, 2016. Results The search provided 130 titles and four studies fulfilled the inclusion criteria. All the included studies were characterized by high risk of bias and meta-analysis was not possible due to considerable variation. Both treatment modalities significantly increase the transverse maxillary skeletal and dental arch width. The transverse dental arch expansion and relapse seems to be substantial higher with tooth-borne surgically assisted rapid maxillary expansion compared to segmental Le Fort I osteotomy. The ratio of dental to skeletal relapse was significantly higher in the posterior maxilla with tooth-borne surgically assisted rapid maxillary expansion. Moreover, a parallel opening without segment tilting was observed after segmental Le Fort I osteotomy. Conclusions Maxillary transverse deficiency in adults can be treated successfully with both treatment modalities, although surgically assisted rapid maxillary expansion seems more effective when large transverse maxillary skeletal and dental arch expansion is required. However, considering the methodological limitations of the included studies, long-term randomized studies assessing transverse skeletal and dental expansion and relapse with the two treatment modalities are needed before definite conclusions can be provided. PMID:28154745

Expansion and contraction tension zones in western pinon-juniper woodlands under projected climate change

Treesearch

Jacob Gibson; Gretchen G. Moisen; Tracey S. Frescino; Thomas C. Jr. Edwards

2012-01-01

Populations of pinons and junipers across the interior west have been highly dynamic over the last two centuries, undergoing an overall expansion but punctuated with regional mortality. Accumulating demographic studies across the interior west indicate the drivers of expansion and contraction of populations are compounded by regional land use legacies, but have an...

The Behavioral and Social Sciences: Contributions and Opportunities in Academic Medicine.

PubMed

Smith, Patrick O; Grigsby, R Kevin

2017-06-01

The Association of American Medical Colleges plays a leading role in supporting the expansion and evolution of academic medicine and medical science in North America, which are undergoing high-velocity change. Behavioral and social science concepts have great practical value when applied to the leadership practices and administrative structures that guide and support the rapid evolution of academic medicine and medical sciences. The authors are two behavioral and social science professionals who serve as academic administrators in academic medical centers. They outline their career development and describe the many ways activities have been shaped by their work with the Association of American Medical Colleges. Behavioral and social science professionals are encouraged to become change agents in the ongoing transformation of academic medicine.

Immediate impact of rapid maxillary expansion on upper airway dimensions and on the quality of life of mouth breathers.

PubMed

Izuka, Edna Namiko; Feres, Murilo Fernando Neuppmann; Pignatari, Shirley Shizue Nagata

2015-01-01

To assess short-term tomographic changes in the upper airway dimensions and quality of life of mouth breathers after rapid maxillary expansion (RME). A total of 25 mouth breathers with maxillary atresia and a mean age of 10.5 years old were assessed by means of cone-beam computed tomography (CBCT) and a standardized quality of life questionnaire answered by patients' parents/legal guardians before and immediately after rapid maxillary expansion. Rapid maxillary expansion resulted in similar and significant expansion in the width of anterior (2.8 mm, p < 0.001) and posterior nasal floor (2.8 mm, p < 0.001). Although nasopharynx and nasal cavities airway volumes significantly increased (+1646.1 mm3, p < 0.001), oropharynx volume increase was not statistically significant (+1450.6 mm3, p = 0.066). The results of the quality of life questionnaire indicated that soon after rapid maxillary expansion, patients' respiratory symptoms significantly decreased in relation to their initial respiratory conditions. It is suggested that RME produces significant dimensional increase in the nasal cavity and nasopharynx. Additionally, it also positively impacts the quality of life of mouth-breathing patients with maxillary atresia.

Salvage rapid maxillary expansion for the relapse of maxillary transverse expansion after Le Fort I with parasagittal osteotomy

PubMed Central

2015-01-01

Maxillary transverse deficiency is one of the most common deformities among occlusal discrepancies. Typical surgical methods are segmental Le Fort I osteotomy and surgically-assisted rapid maxillary expansion (SARME). This patient underwent a parasagittal split with a Le Fort I osteotomy to correct transverse maxillary deficiency. During follow-up, early transverse relapse occurred and rapid maxillary expansion (RME) application with removal of the fixative plate on the constricted side was able to regain the dimension again. RME application may be appropriate salvage therapy for such a case. PMID:25922822

Gateway Arch Circulator Conceptual Feasibility Study : Jefferson National Expansion Memorial

DOT National Transportation Integrated Search

2015-03-01

The Jefferson National Expansion Memorial (JEFF) is undergoing major design changes as part of the City Arch River 2015 project (CAR) that will impact access for park visitors. The park and stakeholders are considering a circulator system to facilita...

The development of shock wave overpressure driven by channel expansion of high current impulse discharge arc

NASA Astrophysics Data System (ADS)

Xiong, Jia-ming; Li, Lee; Dai, Hong-yu; Wu, Hai-bo; Peng, Ming-yang; Lin, Fu-chang

2018-03-01

During the formation of a high current impulse discharge arc, objects near the discharge arc will be strongly impacted. In this paper, a high power, high current gas switch is used as the site of the impulse discharge arc. The explosion wave theory and the arc channel energy balance equation are introduced to analyze the development of the shock wave overpressure driven by the high current impulse discharge arc, and the demarcation point of the arc channel is given, from which the energy of the arc channel is no longer converted into shock waves. Through the analysis and calculation, it is found that the magnitude of the shock wave overpressure caused by impulse discharge arc expansion is closely related to the arc current rising rate. The arc shock wave overpressure will undergo a slow decay process and then decay rapidly. The study of this paper will perform the function of deepening the understanding of the physical nature of the impulse arc discharge, which can be used to explain the damage effect of the high current impulse discharge arc.

Plasma and magnetic field variations in the distant magnetotail associated with near-earth substorm effects

NASA Technical Reports Server (NTRS)

Baker, D. N.; Bame, S. J.; Mccomas, D. J.; Zwickl, R. D.; Slavin, J. A.; Smith, E. J.

1987-01-01

Examination of many individual event periods in the ISEE 3 deep-tail data set has suggested that magnetospheric substorms produce a characteristic pattern of effects in the distant magnetotail. During the growth, or tail-energy-storage phase of substorms, the magnetotail appears to grow diametrically in size, often by many earth radii. Subsequently, after the substorm expansive phase onset at earth, the distant tail undergoes a sequence of plasma, field, and energetic-particle variations as large-scale plasmoids move rapidly down the tail following their disconnection from the near-earth plasma sheet. ISEE 3 data are appropriate for the study of these effects since the spacecraft remained fixed within the nominal tail location for long periods. Using newly available auroral electrojet indices (AE and AL) and Geo particle data to time substorm onsets at earth, superposed epoch analyses of ISEE 3 and near-earth data prior to, and following, substorm expansive phase onsets have been performed. These analyses quantify and extend substantially the understanding of the deep-tail pattern of response to global substorm-induced dynamical effects.

Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

NASA Astrophysics Data System (ADS)

Jiao, L. M.; Tang, X.; Liu, X. P.

2017-09-01

Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

Current Progresses of Single Cell DNA Sequencing in Breast Cancer Research.

PubMed

Liu, Jianlin; Adhav, Ragini; Xu, Xiaoling

2017-01-01

Breast cancers display striking genetic and phenotypic diversities. To date, several hypotheses are raised to explain and understand the heterogeneity, including theories for cancer stem cell (CSC) and clonal evolution. According to the CSC theory, the most tumorigenic cells, while maintaining themselves through symmetric division, divide asymmetrically to generate non-CSCs with less tumorigenic and metastatic potential, although they can also dedifferentiate back to CSCs. Clonal evolution theory recapitulates that a tumor initially arises from a single cell, which then undergoes clonal expansion to a population of cancer cells. During tumorigenesis and evolution process, cancer cells undergo different degrees of genetic instability and consequently obtain varied genetic aberrations. Yet the heterogeneity in breast cancers is very complex, poorly understood and subjected to further investigation. In recent years, single cell sequencing (SCS) technology developed rapidly, providing a powerful new way to better understand the heterogeneity, which may lay foundations to some new strategies for breast cancer therapies. In this review, we will summarize development of SCS technologies and recent advances of SCS in breast cancer.

The Effects of Surgical Rapid Maxillary Expansion (SRME) on Vowel Formants

ERIC Educational Resources Information Center

Sari, Emel; Kilic, Mehmet Akif

2009-01-01

The objective of this study was to investigate the effect of surgical rapid maxillary expansion (SRME) on vowel production. The subjects included 12 patients, whose speech were considered perceptually normal, that had undergone surgical RME for expansion of a narrow maxilla. They uttered the following Turkish vowels, ([a], [[epsilon

Synthesis of Energetic Materials by Rapid Expansion of a Supercritical Solution into Aqueous Solution (RESS-AS) Process

DTIC Science & Technology

2010-12-02

1366-1373, (2005). 16. Young, T . J ., Mawson , S., Johnston, K. P., Henriksen, I. B., Pace, G. W., and Mishra, A. K., Rapid Expansion from...Synthesis of Energetic Materials by Rapid Expansion of a Supercritical Solution into Aqueous Solution (RESS-AS) Process* J . T . Essel, A. C...Cortopassi, K. K. Kuo, J . H. Adair, and C. G. Leh The Pennsylvania State University University Park, PA 16802 USA T . M. Klapötke Ludwig Maximilian

Large-Scale Culture and Genetic Modification of Human Natural Killer Cells for Cellular Therapy.

PubMed

Lapteva, Natalia; Parihar, Robin; Rollins, Lisa A; Gee, Adrian P; Rooney, Cliona M

2016-01-01

Recent advances in methods for the ex vivo expansion of human natural killer (NK) cells have facilitated the use of these powerful immune cells in clinical protocols. Further, the ability to genetically modify primary human NK cells following rapid expansion allows targeting and enhancement of their immune function. We have successfully adapted an expansion method for primary NK cells from peripheral blood mononuclear cells or from apheresis products in gas permeable rapid expansion devices (G-Rexes). Here, we describe an optimized protocol for rapid and robust NK cell expansion as well as a method for highly efficient retroviral transduction of these ex vivo expanded cells. These methodologies are good manufacturing practice (GMP) compliant and could be used for clinical-grade product manufacturing.

Standard cosmology delayed

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

Choudhury, Debajyoti; Ghoshal, Debashis; Sen, Anjan Ananda, E-mail: debajyoti.choudhury@gmail.com, E-mail: dghoshal@mail.jnu.ac.in, E-mail: anjan.ctp@jmi.ac.in

2012-02-01

The introduction of a delay in the Friedmann equation of cosmological evolution is shown to result in the very early universe undergoing the necessary accelerated expansion in the usual radiation (or matter) dominated phase. Occurring even without a violation of the strong energy condition, this expansion slows down naturally to go over to the decelerated phase, namely the standard Hubble expansion. This may obviate the need for a scalar field driven inflationary epoch.

Unusual thermal expansion of Sr{sub 2}IrO{sub 4}: A variable temperature synchrotron X-ray diffraction study

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

Ranjbar, Ben; Kennedy, Brendan J.

The structure of Sr{sub 2}IrO{sub 4} has been studied between 20 and 1273 K using synchrotron X-ray diffraction. Sr{sub 2}IrO{sub 4} undergoes an apparently continuous transition from I4{sub 1}/acd to I4/mmm near 1123 K. The cooperative tilting of the corner sharing IrO{sub 6} octahedra in I4{sub 1}/acd results in highly anisotropic and unusual thermal expansion behavior with negative thermal expansion along the c-axis. - Graphical abstract: The progressive reduction in the magnitude of the tilting of the corner sharing IrO{sub 6} octahedra in Sr{sub 2}IrO{sub 4} results in negative thermal expansion along the c-axis before undergoing an apparently continuous transitionmore » from I4{sub 1}/acd to I4/mmm near 1123 K. - Highlights: • Thermal expansion of Sr{sub 2}IrO{sub 4} was studied using Synchrotron-XRD. • Unusual negative thermal expansion along c-axis observed. • I4{sub 1}/acd→I4/mmm phase transition detected near 1120 K. • Tilting of the corner sharing IrO{sub 6} octahedra related to the observed NTE.« less

Surgically assisted rapid maxillary expansion in adults.

PubMed

Pogrel, M A; Kaban, L B; Vargervik, K; Baumrind, S

1992-01-01

Twelve adults with maxillary width discrepancy of greater than 5 mm were treated by surgically assisted rapid maxillary expansion. The procedure consisted of bilateral zygomatic buttress and midpalatal osteotomies combined with the use of a tooth-borne orthopedic device postoperatively. Mean palatal expansion of 7.5 mm (range of 6 to 13 mm), measured in the first molar region, was achieved within 3 weeks in all patients. Expansion remained stable during the 12-month study period, with a mean relapse for the entire group of 0.88 +/- 0.48 mm. Morbidity was limited to mild postoperative discomfort. The results of this preliminary study indicated that surgically assisted rapid maxillary expansion is a safe, simple, and reliable procedure for achieving a permanent increase in skeletal maxillary width in adults. Further study is necessary to document the three-dimensional movements of the maxillary segments and long-term stability of the skeletal and dental changes.

Bimodal ex vivo expansion of T cells from patients with head and neck squamous cell carcinoma: a prerequisite for adoptive cell transfer.

PubMed

Junker, Niels; Andersen, Mads Hald; Wenandy, Lynn; Dombernowsky, Sarah Louise; Kiss, Katalin; Sørensen, Christian Hjort; Therkildsen, Marianne Hamilton; Von Buchwald, Christian; Andersen, Elo; Straten, Per Thor; Svane, Inge Marie

2011-08-01

Adoptive transfer of tumor-infiltrating lymphocytes (TIL) has proven effective in metastatic melanoma and should therefore be explored in other types of cancer. The aim of this study was to examine the feasibility of potentially expanding clinically relevant quantities of tumor-specific T-cell cultures from TIL from patients with head and neck squamous cell carcinoma (HNSCC) using a more rapid expansion procedure compared with previous HNSCC studies. In a two-step expansion process, initially TIL bulk cultures were established from primary and recurrent HNSCC tumors in high-dose interleukin (IL)-2. Secondly, selected bulk cultures were rapidly expanded using anti-CD3 antibody, feeder cells and high-dose IL-2. T-cell subsets were phenotypically characterized using flow cytometry. T-cell receptor (TCR) clonotype mapping was applied to examine clonotype dynamics during culture. Interferon (INF)-γ detection by Elispot and Cr(51) release assay determined the specificity and functional capacity of selected TIL pre- and post-rapid expansion. TIL bulk cultures were expanded in 80% of the patients included, showing tumor specificity in 60% of the patients. Rapid expansions generated up to 3500-fold expansion of selected TIL cultures within 17 days. The cultures mainly consisted of T-effector memory cells, with varying distributions of CD8(+) and CD4(+) subtypes both among cultures and patients. TCR clonotype mapping demonstrated oligoclonal expanded cultures, ranging from approximately 10 to 30 T-cell clonotypes. TIL from large-scale rapid expansions maintained functional capacity, and contained tumor-specific T cells. The procedure is feasible for expansion of TIL from HNSCC, ensuring clinically relevant expansion folds within 7 weeks. The cell culture kinetics and phenotypes of the TIL resemble previously published results on TIL from melanoma, setting the stage for clinical testing of this promising treatment strategy for patients with HNSCC.

Kinetic or Dynamic Control on a Bifurcating Potential Energy Surface? An Experimental and DFT Study of Gold-Catalyzed Ring Expansion and Spirocyclization of 2-Propargyl-β-tetrahydrocarbolines.

PubMed

Zhang, Lei; Wang, Yi; Yao, Zhu-Jun; Wang, Shaozhong; Yu, Zhi-Xiang

2015-10-21

In classical transition state theory, a transition state is connected to its reactant(s) and product(s). Recently, chemists found that reaction pathways may bifurcate after a transition state, leading to two or more sets of products. The product distribution for such a reaction containing a bifurcating potential energy surface (bPES) is usually determined by the shape of the bPES and dynamic factors. However, if the bPES leads to two intermediates (other than two products), which then undergo further transformations to give different final products, what factors control the selectivity is still not fully examined. This missing link in transition state theory is founded in the present study. Aiming to develop new methods for the synthesis of azocinoindole derivatives, we found that 2-propargyl-β-tetrahydrocarbolines can undergo ring expansion and spirocyclization under gold catalysis. DFT study revealed that the reaction starts with the intramolecular cyclization of the gold-activated 2-propargyl-β-tetrahydrocarboline with a bPES. The cyclization intermediates can not only interconvert into each other via a [1,5]-alkenyl shift, but also undergo ring expansion (through fragmentation/protodeauration mechanism) or spirocyclization (through deprotonation/protodeauration mechanism). Detailed analysis of the complex PESs for substrates with different substituents indicated that the reaction selectivity is under dynamic control if the interconversion of the intermediates is slower than the ring expansion and spirocyclization processes. Otherwise, the chemical outcome is under typical kinetic control and determined by the relative preference of ring expansion versus spirocyclization pathways. The present study may enrich chemist's understanding of the determinants for selectivities on bPESs.

The Three Clades of the Telomere-Associated TLO Gene Family of Candida albicans Have Different Splicing, Localization, and Expression Features

PubMed Central

Anderson, Matthew Z.; Baller, Joshua A.; Dulmage, Keely; Wigen, Lauren

2012-01-01

Candida albicans grows within a wide range of host niches, and this adaptability enhances its success as a commensal and as a pathogen. The telomere-associated TLO gene family underwent a recent expansion from one or two copies in other CUG clade members to 14 expressed copies in C. albicans. This correlates with increased virulence and clinical prevalence relative to those of other Candida clade species. The 14 expressed TLO gene family members have a conserved Med2 domain at the N terminus, suggesting a role in general transcription. The C-terminal half is more divergent, distinguishing three clades: clade α and clade β have no introns and encode proteins that localize primarily to the nucleus; clade γ sometimes undergoes splicing, and the gene products localize within the mitochondria as well as the nuclei. Additionally, TLOα genes are generally expressed at much higher levels than are TLOγ genes. We propose that expansion of the TLO gene family and the predicted role of Tlo proteins in transcription regulation provide C. albicans with the ability to adapt rapidly to the broad range of different environmental niches within the human host. PMID:22923044

SULFURIZATION OF IRON IN THE DYNAMIC SOLAR NEBULA AND IMPLICATIONS FOR PLANETARY COMPOSITIONS

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

Ciesla, Fred J., E-mail: fciesla@uchicago.edu

One explanation for the enhanced ratio of volatiles to hydrogen in Jupiter’s atmosphere compared to a a gas of solar composition is that the planet accreted volatile-bearing clathrates during its formation. Models, however, suggest that S would be over abundant if clathrates were the primary carrier of Jupiter’s volatiles. This led to the suggestion that S was depleted in the outer nebula due to the formation troilite (FeS). Here, this depletion is quantitatively explored by modeling the coupled dynamical and chemical evolution of Fe grains in the solar nebula. It is found that disks that undergo rapid radial expansion frommore » an initially compact state may allow sufficient production of FeS and carry H{sub 2}S-depleted gas outward where ices would form, providing the conditions needed for S-depleted clathrates to form. However, this expansion would also carry FeS grains to this region, which could also be incorporated into planetesimals. Thus for clathrates to be a viable source of volatiles, models must account for the presence of both H{sub 2}S in FeS in the outer solar nebula.« less

Biomechanical effects of maxillary expansion on a patient with cleft palate: A finite element analysis

PubMed Central

Lee, Haofu; Nguyen, Alan; Hong, Christine; Hoang, Paul; Pham, John; Ting, Kang

2017-01-01

Introduction The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model. Methods A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP. Results High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment. Conclusions The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP. PMID:27476365

Biomechanical effects of maxillary expansion on a patient with cleft palate: A finite element analysis.

PubMed

Lee, Haofu; Nguyen, Alan; Hong, Christine; Hoang, Paul; Pham, John; Ting, Kang

2016-08-01

The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model. A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP. High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment. The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Composition, response to pressure, and negative thermal expansion in M IIB IVF 6 (M = Ca, Mg; B = Zr, Nb) [Composition, response to pressure, and negative thermal expansion in A IIB IVF 6; A - Ca, Mg, B - Zr, Nb

DOE PAGES

Hester, Brett R.; Hancock, Justin C.; Lapidus, Saul H.; ...

2016-12-27

CaZrF 6 has recently been shown to combine strong negative thermal expansion (NTE) over a very wide temperature range (at least 10–1000 K) with optical transparency from mid-IR into the UV range. Variable-temperature and high-pressure diffraction has been used to determine how the replacement of calcium by magnesium and zirconium by niobium(IV) modifies the phase behavior and physical properties of the compound. Similar to CaZrF 6, CaNbF 6 retains a cubic ReO 3-type structure down to 10 K and displays NTE up until at least 900 K. It undergoes a reconstructive phase transition upon compression to ~400 MPa at room temperature and pressure-induced amorphization above ~4 GPa. Prior to the first transition, it displays very strong pressure-induced softening. MgZrF 6 adopts a cubic ( Fmmore » $$\\bar{3}$$m) structure at 300 K and undergoes a symmetry-lowering phase transition involving octahedral tilts at ~100 K. Immediately above this transition, it shows modest NTE. Its’ thermal expansion increases upon heating, crossing through zero at ~500 K. Unlike CaZrF 6 and CaNbF 6, it undergoes an octahedral tilting transition upon compression (~370 MPa) prior to a reconstructive transition at ~1 GPa. Cubic MgZrF 6 displays both pressure-induced softening and stiffening upon heating. MgNbF 6 is cubic ( Fm$$\\bar{3}$$m) at room temperature, but it undergoes a symmetry-lowering octahedral tilting transition at ~280 K. It does not display NTE within the investigated temperature range (100–950 K). Furthermore the replacement of Zr(IV) by Nb(IV) leads to minor changes in phase behavior and properties, the replacement of the calcium by the smaller and more polarizing magnesium leads to large changes in both phase behavior and thermal expansion.« less

Composition, response to pressure, and negative thermal expansion in M IIB IVF 6 (M = Ca, Mg; B = Zr, Nb) [Composition, response to pressure, and negative thermal expansion in A IIB IVF 6; A - Ca, Mg, B - Zr, Nb

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

Hester, Brett R.; Hancock, Justin C.; Lapidus, Saul H.

CaZrF 6 has recently been shown to combine strong negative thermal expansion (NTE) over a very wide temperature range (at least 10–1000 K) with optical transparency from mid-IR into the UV range. Variable-temperature and high-pressure diffraction has been used to determine how the replacement of calcium by magnesium and zirconium by niobium(IV) modifies the phase behavior and physical properties of the compound. Similar to CaZrF 6, CaNbF 6 retains a cubic ReO 3-type structure down to 10 K and displays NTE up until at least 900 K. It undergoes a reconstructive phase transition upon compression to ~400 MPa at room temperature and pressure-induced amorphization above ~4 GPa. Prior to the first transition, it displays very strong pressure-induced softening. MgZrF 6 adopts a cubic ( Fmmore » $$\\bar{3}$$m) structure at 300 K and undergoes a symmetry-lowering phase transition involving octahedral tilts at ~100 K. Immediately above this transition, it shows modest NTE. Its’ thermal expansion increases upon heating, crossing through zero at ~500 K. Unlike CaZrF 6 and CaNbF 6, it undergoes an octahedral tilting transition upon compression (~370 MPa) prior to a reconstructive transition at ~1 GPa. Cubic MgZrF 6 displays both pressure-induced softening and stiffening upon heating. MgNbF 6 is cubic ( Fm$$\\bar{3}$$m) at room temperature, but it undergoes a symmetry-lowering octahedral tilting transition at ~280 K. It does not display NTE within the investigated temperature range (100–950 K). Furthermore the replacement of Zr(IV) by Nb(IV) leads to minor changes in phase behavior and properties, the replacement of the calcium by the smaller and more polarizing magnesium leads to large changes in both phase behavior and thermal expansion.« less

Rapid fibroblast removal from high density human embryonic stem cell cultures.

PubMed

Turner, William S; McCloskey, Kara E

2012-10-28

Mouse embryonic fibroblasts (MEFs) were used to establish human embryonic stem cells (hESCs) cultures after blastocyst isolation(1). This feeder system maintains hESCs from undergoing spontaneous differentiation during cell expansion. However, this co-culture method is labor intensive, requires highly trained personnel, and yields low hESC purity(4). Many laboratories have attempted to minimize the number of feeder cells in hESC cultures (i.e. incorporating matrix-coated dishes or other feeder cell types(5-8)). These modified culture systems have shown some promise, but have not supplanted the standard method for culturing hESCs with mitomycin C-treated mouse embyronic fibroblasts in order to retard unwanted spontaneous differentiation of the hESC cultures. Therefore, the feeder cells used in hESC expansion should be removed during differentiation experiments. Although several techniques are available for purifying the hESC colonies (FACS, MACS, or use of drug resistant vectors) from feeders, these techniques are labor intensive, costly and/or destructive to the hESC. The aim of this project was to invent a method of purification that enables the harvesting of a purer population of hESCs. We have observed that in a confluent hESC culture, the MEF population can be removed using a simple and rapid aspiration of the MEF sheet. This removal is dependent on several factors, including lateral cell-to-cell binding of MEFs that have a lower binding affinity to the styrene culture dish, and the ability of the stem cell colonies to push the fibroblasts outward during the generation of their own "niche". The hESC were then examined for SSEA-4, Oct3/4 and Tra 1-81 expression up to 10 days after MEF removal to ensure maintenance of pluripotency. Moreover, hESC colonies were able to continue growing from into larger formations after MEF removal, providing an additional level of hESC expansion.

[Spatiotemporal characteristics of urban land expansion in central area of Shanghai, China].

PubMed

Hu, Han-Wen; Wei, Ben-Sheng; Shen, Xing-Hua; Li, Jun-Xiang

2013-12-01

Using the high spatial resolution (2.5 m) color-infrared aerial photos acquired in 1989, 1994, 2000 and 2005, this paper analyzed the spatiotemporal characteristics of rapid urban expansion in central Shanghai with urban expansion intensity index and gradient analysis. Results showed that urban land use in Shanghai increased rapidly in a "pancake" style during the study period, and the anisotropic urban expansion moved the urban center 2.62 km toward southwest. The urban land use expansion intensity doubled and showed a rural-urban gradient. The most intensive urban expansion zone fell in the rural-urban transition zone, indicating the dominance of peripheral expansion as the primary urban expansion mode in Shanghai. However, the urban land use intensity decreased with time at the urban center. The primary driving forces of urban expansion included support from government policies and decision-making, enhanced economic activities, societal fixed assets investment, urban infrastructure investment, extension of transportation routes, as well as increase in urban population.

Laser and LED phototherapy on midpalatal suture after rapid maxilla expansion: Raman and histological analysis.

PubMed

Rosa, Cristiane Becher; Habib, Fernando Antonio Lima; de Araújo, Telma Martins; Dos Santos, Jean Nunes; Cangussu, Maria Cristina T; Barbosa, Artur Felipe Santos; de Castro, Isabele Cardoso Vieira; Pinheiro, Antônio Luiz Barbosa

2017-02-01

The aim of this study was to analyze the effect of laser or LED phototherapy on the acceleration of bone formation at the midpalatal suture after rapid maxilla expansion. Forty-five rats were divided into groups at 7 days (control, expansion, expansion and laser irradiation, and expansion and LED irradiation) and into 14 days (expansion, expansion and laser in the 1st week, expansion and LED in the 1st week, expansion and laser in the 1st and 2nd weeks, expansion and LED in the 1st and 2nd weeks). Laser/LED irradiation occurred every 48 h. Expansion was accomplished with a spatula and maintained with a triple helicoid of 0.020-in stainless steel orthodontic wire. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm 2 , t = 257 s, SAEF of 18 J/cm 2 ) or a LED (λ850 ± 10 nm, 150 ± 10 mW, spot of 0.5 cm 2 , t = 120 s, SAEF of 18 J/cm 2 ) was applied in one point in the midpalatal suture immediately behind the upper incisors. Raman spectroscopy and histological analyses of the suture region were carried and data was submitted to statistical analyses (p ≤ 0.05). Raman spectrum analysis demonstrated that irradiation increases hydroxyapatite in the midpalatal suture after expansion. In the histological analysis of various inflammation, there was a higher production of collagen and osteoblastic activity and less osteoclastic activity. The results showed that LED irradiation associated to rapid maxillary expansion improves bone repair and could be an alternative to the use of laser in accelerating bone formation in the midpalatal suture.

Sakurai's Object Continues to Brighten and Expand

NASA Astrophysics Data System (ADS)

Hinkle, Kenneth H.; Joyce, Richard R.; Matheson, Thomas

2017-01-01

Sakurai's Object (V4334 Sgr), the prototype final flash object discovered in the mid-1990s, was observed to undergo rapid cooling becoming as faint as 25th magnitude at K during the first decade of the 21st century. A review of imaging data suggests the minimum K magnitude occurred about 2006. Sakuarai's Object was re-acquired at K in 2010. Between 2010 Sep and 2013 Apr Sakurai's object brightened more than 2 magnitudes to K=14.2. Here we report on a Gemini-NIRI K band AO image obtained in 2016 July. The Ks magnitude was 13.35. The AO image also records the continuing expansion of the debris cloud. The central star remains obscured. Spectro-spatial NIFS images of the spectral region around He I 1.0830 micron and a GMOS optical spectrum, both observed in 2015, will also be displayed.

Static gas expansion cooler

DOEpatents

Guzek, J.C.; Lujan, R.A.

1984-01-01

Disclosed is a cooler for television cameras and other temperature sensitive equipment. The cooler uses compressed gas ehich is accelerated to a high velocity by passing it through flow passageways having nozzle portions which expand the gas. This acceleration and expansion causes the gas to undergo a decrease in temperature thereby cooling the cooler body and adjacent temperature sensitive equipment.

Craniofacial and upper airway morphology in pediatric sleep-disordered breathing and changes in quality of life with rapid maxillary expansion.

PubMed

Katyal, Vandana; Pamula, Yvonne; Daynes, Cathal N; Martin, James; Dreyer, Craig W; Kennedy, Declan; Sampson, Wayne J

2013-12-01

The association between pediatric sleep-disordered breathing caused by upper airway obstruction and craniofacial morphology is poorly understood and contradictory. The aims of this study were to evaluate the prevalence of children at risk for sleep-disordered breathing, as identified in an orthodontic setting by validated screening questionnaires, and to examine associations with their craniofacial and upper airway morphologies. A further aim was to assess the change in quality of life related to sleep-disordered breathing for affected children undergoing rapid maxillary expansion to correct a palatal crossbite or widen a narrow maxilla. A prospective case-control study with children between 8 and 17 years of age (n = 81) at an orthodontic clinic was undertaken. The subjects were grouped as high risk or low risk for sleep-disordered breathing based on the scores from a validated 22-item Pediatric Sleep Questionnaire and the Obstructive Sleep Apnea-18 Quality of Life Questionnaire. Variables pertaining to a screening clinical examination, cephalometric assessment, and dental cast analysis were tested for differences between the 2 groups at baseline. Ten children who underwent rapid maxillary expansion were followed longitudinally until removal of the appliance approximately 9 months later with a repeated Obstructive Sleep Apnea-18 Quality of Life Questionnaire. All data were collected blinded to the questionnaire results. The frequency of palatal crossbite involving at least 3 teeth was significantly higher in the high-risk group at 68.2%, compared with the low-risk group at 23.2% (P <0.0001). Average quality of life scores in the high-risk group indicated reduced quality of life related to sleep-disordered breathing by 16% compared with children in the low-risk group at baseline (P <0.0001). Cephalometrically, mean inferior airway space, posterior nasal spine to adenoidal mass distance, and adenoidal mass to soft palate distance were reduced in the high-risk group compared with the low-risk group by 1.87 mm (P <0.03), 2.82 mm (P <0.04), and 2.13 mm (P <0.03), respectively. The mean maxillary intercanine, maxillary interfirst premolar, maxillary interfirst molar, mandibular intercanine, and mandibular interfirst premolar widths were reduced in the high-risk group compared with the low-risk group by 4.22 mm (P <0.0001), 3.92 mm (P <0.0001), 4.24 mm (P <0.0001), 1.50 mm (P <0.01), and 1.84 mm (P <0.01), respectively. Children treated with rapid maxillary expansion showed an average improvement of 14% in quality of life scores in the high-risk group compared with the low-risk group, which showed a slight worsening in quality of life related to sleep-disordered breathing by an average of 1% (P <0.04), normalizing the quality of life scores in the high-risk children to the baseline scores compared with the low-risk group. Children at high risk for sleep-disordered breathing are characterized by reduced quality of life, reduced nasopharyngeal and oropharyngeal sagittal dimensions, palatal crossbite, and reduced dentoalveolar transverse widths in the maxillary and mandibular arches. No sagittal or vertical craniofacial skeletal cephalometric predictors were identified for children at high risk for sleep-disordered breathing. In the short term, rapid maxillary expansion might aid in improvement of the quality of life for children with a narrow maxilla in the milder end of the sleep-disordered breathing spectrum. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Rapid replacement of bridge deck expansion joints study - phase I.

DOT National Transportation Integrated Search

2014-12-01

Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

Accelerated production of antigen-specific T-cells for pre-clinical and clinical applications using Gas-permeable Rapid Expansion cultureware (G-Rex)

PubMed Central

Vera, Juan F.; Brenner, Lara J.; Gerdemann, Ulrike; Ngo, Minhtran C.; Sili, Uluhan; Liu, Hao; Wilson, John; Dotti, Gianpietro; Heslop, Helen E.; Leen, Ann M.; Rooney, Cliona M.

2009-01-01

The clinical manufacture of antigen-specific cytotoxic T lymphocytes (CTL) for adoptive immunotherapy is limited by the complexity and time required to produce large numbers with the desired function and specificity. The culture conditions required are rigorous, and in some cases only achieved in 2cm2 wells in which cell growth is limited by gas exchange, nutrients and waste accumulation. Bioreactors developed to overcome these issues tend to be complex, expensive and not always conducive to CTL growth. We observed that antigen-specific CTL undergo seven to ten divisions post-stimulation. However the expected CTL numbers were achieved only in the first week of culture. By recreating the culture conditions present during this first week - low frequency of antigen-specific T-cells and high frequency of feeder cells - we were able to increase CTL expansion to expected levels which could be sustained for several weeks without affecting phenotype or function. However, the number of 24-well plates needed was excessive and cultures required frequent media changes, increasing complexity and manufacturing costs. Therefore, we evaluated novel gas-permeable culture devices (G-Rex) with a silicone membrane at the base allowing gas exchange to occur uninhibited by depth of medium above. This system effectively supports the expansion of CTL and actually increases output by up to 20-fold while decreasing required technician time. Importantly, this amplified cell expansion is not due to more cell divisions but to reduced cell death. This bioprocess optimization increased T-cell output while decreasing the complexity and cost of CTL manufacture, making cell therapy more accessible. PMID:20445351

Cryopreservation of Viable Human Lung Tissue for Versatile Post-thaw Analyses and Culture

PubMed Central

Baatz, John E.; Newton, Danforth A.; Riemer, Ellen C.; Denlinger, Chadrick E.; Jones, E. Ellen; Drake, Richard R.; Spyropoulos, Demetri D.

2018-01-01

Clinical trials are currently used to test therapeutic efficacies for lung cancer, infections and diseases. Animal models are also used as surrogates for human disease. Both approaches are expensive and time-consuming. The utility of human biospecimens as models is limited by specialized tissue processing methods that preserve subclasses of analytes (e.g. RNA, protein, morphology) at the expense of others. We present a rapid and reproducible method for the cryopreservation of viable lung tissue from patients undergoing lobectomy or transplant. This method involves the pseudo-diaphragmatic expansion of pieces of fresh lung tissue with cryoprotectant formulation (pseudo-diaphragmatic expansion-cryoprotectant perfusion or PDX-CP) followed by controlled-rate freezing in cryovials. Expansion-perfusion rates, volumes and cryoprotectant formulation were optimized to maintain tissue architecture, decrease crystal formation and increase long-term cell viability. Rates of expansion of 4 cc/min or less and volumes ranging from 0.8–1.2 × tissue volume were well-tolerated by lung tissue obtained from patients with chronic obstructive pulmonary disease or idiopathic pulmonary fibrosis, showing minimal differences compared to standard histopathology. Morphology was greatly improved by the PDX-CP procedure compared to simple fixation. Fresh versus post-thawed lung tissue showed minimal differences in histology, RNA integrity numbers and post-translational modified protein integrity (2-dimensional differential gel electrophoresis). It was possible to derive numerous cell types, including alveolar epithelial cells, fibroblasts and stem cells, from the tissue for at least three months after cryopreservation. This new method should provide a uniform, cost-effective approach to the banking of biospecimens, with versatility to be amenable to any post-acquisition process applicable to fresh tissue samples. PMID:24982205

Effects of landuse change on the hydrologic regime of the Mae Chaem river basin, NW Thailand

NASA Astrophysics Data System (ADS)

Thanapakpawin, P.; Richey, J.; Thomas, D.; Rodda, S.; Campbell, B.; Logsdon, M.

2007-02-01

SummaryConflicts between upland shifting cultivation, upland commercial crops, and lowland irrigated agriculture cause water resource tension in the Mae Chaem watershed in Chiang Mai, Thailand. In this paper, we assess hydrologic regimes of the Mae Chaem River with landuse change. Three plausible future forest-to-crop expansion scenarios and a scenario of crop-to-forest reversal were developed based on the landcover transition from 1989 to 2000, with emphasis on influences of elevation bands and irrigation diversion. Basin hydrologic responses were simulated using the Distributed Hydrology Soil Vegetation Model (DHSVM). Meteorological data from six weather stations inside and adjacent to the Mae Chaem watershed during the period 1993-2000 were the climate inputs. Computed stream flow was compared to observed discharge at Ban Mae Mu gauge on Mae Mu river, Ban Mae Suk gauge on Mae Suk river, and at Kaeng Ob Luang, located downstream from the district town in Mae Chaem. With current assumptions, expansion of highland crop fields led to slightly higher regulated annual and wet-season water yields compared to similar expansion in the lowland-midland zone. Actual downstream water availability was sensitive to irrigation diversion. This modeling approach can be a useful tool for water allocation for small watersheds undergoing rapid commercialization, because it alerts land managers to the potential range of water supply in wet and dry seasons, and provides information on spatial distribution of basin hydrologic components.

Morphologic changes of the nasal cavity induced by rapid maxillary expansion: a study on 3-dimensional computed tomography models.

PubMed

Haralambidis, Adam; Ari-Demirkaya, Arzu; Acar, Ahu; Küçükkeleş, Nazan; Ateş, Mustafa; Ozkaya, Selin

2009-12-01

The aim of this study was to evaluate the effect of rapid maxillary expansion on the volume of the nasal cavity by using computed tomography. The sample consisted of 24 patients (10 boys, 14 girls) in the permanent dentition who had maxillary constriction and bilateral posterior crossbite. Ten patients had skeletal Class I and 14 had Class II relationships. Skeletal maturity was assessed with the modified cervical vertebral maturation method. Computed tomograms were taken before expansion and at the end of the 3-month retention period, after active expansion. The tomograms were analyzed by Mimics software (version 10.11, Materialise Medical Co, Leuven, Belgium) to reconstruct 3-dimensional images and calculate the volume of the nasal cavities before and after expansion. A significant (P = 0.000) average increase of 11.3% in nasal volume was found. Sex, growth, and skeletal relationship did not influence measurements or response to treatment. A significant difference was found in the volume increase between the Class I and Class II patients, but it was attributed to the longer expansion period of the latter. Therefore, rapid maxillary expansion induces a significant average increase of the nasal volume and consequently can increase nasal permeability and establish a predominant nasal respiration pattern.

A new subtype of progenitor cell in the mouse embryonic neocortex

PubMed Central

Wang, Xiaoqun; Tsai, Jin-Wu; LaMonica, Bridget; Kriegstein, Arnold R.

2011-01-01

A hallmark of mammalian brain evolution is cortical expansion, which reflects an increase in the number of cortical neurons established by the progenitor cell subtypes present and the number of their neurogenic divisions. Recent studies have revealed a new class of radial glia-like (oRG) progenitor cells in the human brain, which reside in the outer subventricular zone. Expansion of the subventricular zone and appearance of oRG cells may have been essential evolutionary steps leading from lissencephalic to gyrencephalic neocortex. Here we show that oRG-like progenitor cells are present in the mouse embryonic neocortex. They arise from asymmetric divisions of radial glia and undergo self-renewing asymmetric divisions to generate neurons. Moreover, mouse oRG cells undergo mitotic somal translocation whereby centrosome movement into the basal process during interphase preceeds nuclear translocation. Our finding of oRG cells in the developing rodent brain fills a gap in our understanding of neocortical expansion. PMID:21478886

Inhibition of cell expansion by rapid ABP1-mediated auxin effect on microtubules

PubMed Central

Chen, Xu; Grandont, Laurie; Li, Hongjiang; Hauschild, Robert; Paque, Sébastien; Abuzeineh, Anas; Rakusová, Hana; Benkova, Eva; Perrot-Rechenmann, Catherine; Friml, Jiří

2014-01-01

The prominent and evolutionary ancient effect of the plant hormone auxin is the regulation of cell expansion1. Cell expansion requires ordered cytoskeleton arrangement2 but molecular mechanisms underlying its regulation by signaling molecules including auxin are unknown. Here we show in the model plant Arabidopsis thaliana that in elongating cells exogenous application of auxin or redistribution of endogenous auxin induces very rapid microtubule reorientation from transversal to longitudinal, coherent with the inhibition of cell expansion. This fast auxin effect requires Auxin Binding Protein1 (ABP1) and involves a contribution of downstream signaling components such as ROP6 GTPase, ROP-interactive protein RIC1 and microtubule severing protein Katanin. These components are required for rapid auxin and ABP1-mediated reorientation of microtubules to regulate cell elongation in roots and dark grown hypocotyls as well as asymmetric growth during gravitropic responses. PMID:25409144

Clinical scale rapid expansion of lymphocytes for adoptive cell transfer therapy in the WAVE® bioreactor

PubMed Central

2012-01-01

Background To simplify clinical scale lymphocyte expansions, we investigated the use of the WAVE®, a closed system bioreactor that utilizes active perfusion to generate high cell numbers in minimal volumes. Methods We have developed an optimized rapid expansion protocol for the WAVE bioreactor that produces clinically relevant numbers of cells for our adoptive cell transfer clinical protocols. Results TIL and genetically modified PBL were rapidly expanded to clinically relevant scales in both static bags and the WAVE bioreactor. Both bioreactors produced comparable numbers of cells; however the cultures generated in the WAVE bioreactor had a higher percentage of CD4+ cells and had a less activated phenotype. Conclusions The WAVE bioreactor simplifies the process of rapidly expanding tumor reactive lymphocytes under GMP conditions, and provides an alternate approach to cell generation for ACT protocols. PMID:22475724

Crop domestication facilitated rapid geographic expansion of a specialist pollinator, the squash bee Peponapis pruinosa

USDA-ARS?s Scientific Manuscript database

Over the past 10,000 years, humans have facilitated rapid range expansions of animal, plants and microorganisms, often accompanying agriculture’s spread. Three squash species were early domesticates in the New World. Their spreading cultivation out of the Southwest across much of today’s USA has bee...

[Application of supercritical solution rapid expansion technology in preparation of fine pharmacal particles].

PubMed

Zhang, Zhong-yi; Li, Hong-lei; Lei, Zheng-jie

2006-12-01

Rapid expansion of supercritical solution (RESS), a new technology, has been developed in the recent years. Fundamental principle of RESS technology used to prepare fine pharmacal particles was summarized in this paper. A brief review of factors which influenced the process of RESS and application of RESS technology were introduced.

The C. elegans engrailed homolog ceh-16 regulates the self-renewal expansion division of stem cell-like seam cells.

PubMed

Huang, Xinxin; Tian, E; Xu, Yanhua; Zhang, Hong

2009-09-15

Stem cells undergo symmetric and asymmetric division to maintain the dynamic equilibrium of the stem cell pool and also to generate a variety of differentiated cells. The homeostatic mechanism controlling the choice between self-renewal and differentiation of stem cells is poorly understood. We show here that ceh-16, encoding the C. elegans ortholog of the transcription factor Engrailed, controls symmetric and asymmetric division of stem cell-like seam cells. Loss of function of ceh-16 causes certain seam cells, which normally undergo symmetric self-renewal expansion division with both daughters adopting the seam cell fate, to divide asymmetrically with only one daughter retaining the seam cell fate. The human engrailed homolog En2 functionally substitutes the role of ceh-16 in promoting self-renewal expansion division of seam cells. Loss of function of apr-1, encoding the C. elegans homolog of the Wnt signaling component APC, results in transformation of self-renewal maintenance seam cell division to self-renewal expansion division, leading to seam cell hyperplasia. The apr-1 mutation suppresses the seam cell division defect in ceh-16 mutants. Our study reveals that ceh-16 interacts with the Wnt signaling pathway to control the choice between self-renewal expansion and maintenance division and also demonstrates an evolutionarily conserved function of engrailed in promoting cell proliferation.

Co-precipitation of asiatic acid and poly( l-lactide) using rapid expansion of subcritical solutions into liquid solvents

NASA Astrophysics Data System (ADS)

Sane, Amporn; Limtrakul, Jumras

2011-09-01

Poly( l-lactide) (PLLA) nanoparticles loaded with asiatic acid (AA) were successfully produced by rapid expansion of a subcritical solution into an aqueous receiving solution containing a dispersing agent. A mixture of carbon dioxide (CO2) and ethanol (EtOH) with a weight ratio of 1:1 was used as the solvent for AA and PLLA. Two surfactants, Pluronic F127 and sodium dodecyl sulfate were employed. The former was found to be more effective for stabilizing AA-loaded PLLA nanoparticles, as a rapid expansion into a 0.1 wt% Pluronic F127 solution produced a stable nanosuspension consisting mainly of well-dispersed, individual nanoparticles. The effects of rapid expansion-processing conditions—AA to PLLA weight ratio and pre-expansion temperature (Tpre)—on the size and morphology of composite nanoparticles, and the loading capacity and entrapment efficiency of AA in PLLA nanoparticles, were systematically investigated. It was found that AA-loaded PLLA nanoparticles with a size range of 30-100 nm were consistently fabricated by rapid expansion at Tpre of 70-100 °C and AA to PLLA weight ratios of 1:2 and 1:4, and with a constant pre-expansion pressure of 330 bar. The Tpre and AA to PLLA weight ratio had no significant effects on the size of the nanoparticles. The AA to PLLA weight ratio is a controlling parameter for both the loading capacity and the entrapment efficiency of AA in PLLA nanoparticles. The loading capacity and entrapment efficiency increased from 8-11 to 16-21 wt%, and 38-57 to 50-62 wt%, respectively, when the AA to PLLA weight ratio changed from 1:4 to 1:2. However, increasing the Tpre from 70 to 100 °C decreased both the loading capacity and entrapment efficiency of AA in PLLA nanoparticles by 20-30%.

Effects of rapid palatal expansion (RPE) and twin block mandibular advancement device (MAD) on pharyngeal structures in Class II pediatric patients from Cluj-Napoca, Romania.

PubMed

Rădescu, Ovidiu Dănuţ; Colosi, Horațiu Alexandru; Albu, Silviu

2018-05-23

To compare cephalometric changes of pharyngeal structures after rapid palatal expansion (RPE) with those induced by a twin block mandibular advancement device (MAD) with palatal expansion capability. This retrospective study investigated 55 Class II pediatric patients, divided into two groups: 29 patients treated with RPE and 26 patients treated with MAD. Lateral cephalometric measurements were compared before and after treatment. Changes in pharyngeal airway space were statistically significant in both groups (p < 0.001) from a pre-treatment mean distance measured between the lower posterior pharyngeal wall and the hyoid bone (LPF-H) of 25.42 mm in the MAD group and 28.62 mm in the RPE group, to a post-treatment mean LPF-H of 27.96 mm in the MAD group and 31.52 mm in the RPE group. Significant changes in pharyngeal space may be obtained in Class II patients through both rapid palatal expansion and mandibular advancement devices with palatal expansion capability.

C9orf72 repeat expansions in rapid eye movement sleep behaviour disorder.

PubMed

Daoud, Hussein; Postuma, Ronald B; Bourassa, Cynthia V; Rochefort, Daniel; Gauthier, Maude Turcotte; Montplaisir, Jacques; Gagnon, Jean-Francois; Arnulf, Isabelle; Dauvilliers, Yves; Charley, Christelle Monaca; Inoue, Yuichi; Sasai, Taeko; Högl, Birgit; Desautels, Alex; Frauscher, Birgit; Cochen De Cock, Valérie; Rouleau, Guy A; Dion, Patrick A

2014-11-01

A large hexanucleotide repeat expansion in C9orf72 has been identified as the most common genetic cause in familial amyotrophic lateral sclerosis and frontotemporal dementia. Rapid Eye Movement Sleep Behavior Disorder (RBD) is a sleep disorder that has been strongly linked to synuclein-mediated neurodegeneration. The aim of this study was to evaluate the role of the C9orf72 expansions in the pathogenesis of RBD. We amplified the C9orf72 repeat expansion in 344 patients with RBD by a repeat-primed polymerase chain reaction assay. We identified two RBD patients carrying the C9orf72 repeat expansion. Most interestingly, these patients have the same C9orf72 associated-risk haplotype identified in 9p21-linked amyotrophic lateral sclerosis and frontotemporal dementia families. Our study enlarges the phenotypic spectrum associated with the C9orf72 hexanucleotide repeat expansions and suggests that, although rare, this expansion may play a role in the pathogenesis of RBD.

The interactive use of networking multimedia--innovative education resource for professionals and patients.

PubMed

Matthies, H K; Walter, G F; Brandis, A; Stan, A C; Ammann, A; von Jan, U; Porth, A J

1999-01-01

The combination of new and rapidly developing interactive multimedia computers and applications with electronic networks will require a restructuring of our traditional approach to strategic planning and organizational structure. Worldwide telecommunication networks (using satellites, cable) are now facilitating the global pooling of healthcare information and medical knowledge independent of location. The development of multimedia information and communication systems demands cooperative working teams of authors, who are able to master several areas of medical knowledge as well as the presentation of these in different multimedia forms. The assemblage of telematics and services offers a base for multimedia applications, for example teleteaching, telelearning, telepublishing, teleconsulting, teleconferencing, telemedicine etc. The expansion of the internet will also lead to the formation of interdisciplinary "Global Education Networks". The theory and practice of education are undergoing dramatic changes. Lifelong learning and adaptation of medical practice to new knowledge and new techniques will be even more important in the future.

A fiber-reinforced-fluid model of anisotropic plant root cell growth

NASA Astrophysics Data System (ADS)

Jensen, Oliver E.; Dyson, Rosemary J.

2009-11-01

We present a theoretical model of a single cell in the expansion zone of the primary root of the plant Arabidopsis thaliana. The cell undergoes rapid elongation with approximately constant radius. Growth is driven by high internal turgor pressure causing viscous stretching of the cell wall, with embedded cellulose microfibrils providing the wall with strongly anisotropic properties. We represent the cell as a thin cylindrical fiber-reinforced viscous sheet between rigid end plates. Asymptotic reduction of the governing equations, under simple sets of assumptions about fiber and wall properties, yields variants of the traditional Lockhart equation that relates the axial cell growth rate to the internal pressure. The model provides insights into the geometric and biomechanical parameters underlying bulk quantities such as wall extensibility and shows how either dynamical changes in wall material properties or passive fibre reorientation may suppress cell elongation.

Towards establishing compact imaging spectrometer standards

USGS Publications Warehouse

Slonecker, E. Terrence; Allen, David W.; Resmini, Ronald G.

2016-01-01

Remote sensing science is currently undergoing a tremendous expansion in the area of hyperspectral imaging (HSI) technology. Spurred largely by the explosive growth of Unmanned Aerial Vehicles (UAV), sometimes called Unmanned Aircraft Systems (UAS), or drones, HSI capabilities that once required access to one of only a handful of very specialized and expensive sensor systems are now miniaturized and widely available commercially. Small compact imaging spectrometers (CIS) now on the market offer a number of hyperspectral imaging capabilities in terms of spectral range and sampling. The potential uses of HSI/CIS on UAVs/UASs seem limitless. However, the rapid expansion of unmanned aircraft and small hyperspectral sensor capabilities has created a number of questions related to technological, legal, and operational capabilities. Lightweight sensor systems suitable for UAV platforms are being advertised in the trade literature at an ever-expanding rate with no standardization of system performance specifications or terms of reference. To address this issue, both the U.S. Geological Survey and the National Institute of Standards and Technology are eveloping draft standards to meet these issues. This paper presents the outline of a combined USGS/NIST cooperative strategy to develop and test a characterization methodology to meet the needs of a new and expanding UAV/CIS/HSI user community.

[Relationships between urbanization and water resource utilization in Dongting Lake District of South-central China].

PubMed

Li, Jing-Zhi; Zhu, Xiang; Li, Jing-Bao; Xu, Mei

2013-06-01

By using analytic hierarchy process and entropy method, the evaluation index system and the response relationship model of comprehensive development level of urbanization and comprehensive development and utilization potential of water resources in Dongting Lake District were constructed, with the key affecting factors, their change characteristics, and response characteristics from 2001 to 2010 analyzed. During the study period, the Dongting Lake District was undergoing a rapid development of urbanization, and at a scale expansion stage. The economic and social development level was lagged behind the population and area increase, and the quality and efficiency of urbanization were still needed to be improved. With the advance of urbanization, the water consumption increased yearly, and the water resources utilization efficiency and management level improved steadily. However, the background condition of water resources and their development and utilization level were more affected by hydrological environment rather than urbanization. To a certain extent, the development of urbanization in 2001, 2002, 2005, 2006, 2007, 2009 was slowed down by the shortage of water resources. At present, Dongting Lake region was confronted with the dual task of improving the level and quality of urbanization, and hence, it would be necessary to reform the traditional epitaxial expansion of urbanization and to enhance the water resource support capability.

Exploring the Early Structure of a Rapidly Decompressed Particle Bed

NASA Astrophysics Data System (ADS)

Zunino, Heather; Adrian, R. J.; Clarke, Amanda; Johnson, Blair; Arizona State University Collaboration

2017-11-01

Rapid expansion of dense, pressurized beds of fine particles subjected to rapid reduction of the external pressure is studied in a vertical shock tube. A near-sonic expansion wave impinges on the particle bed-gas interface and rapidly unloads the particle bed. A high-speed video camera captures events occurring during bed expansion. The particle bed does not expand homogeneously, but breaks down into horizontal slabs and then transforms into a cellular-type structure. There are several key parameters that affect the particle bed evolution, including particle size and initial bed height. Analyses of this bed structure evolution from experiments with varying particle sizes and initial bed heights is presented. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, Advanced Simulation and Computing Program, as a Cooperative Agreement under the Predictive Science and Academic Alliance Program, under Contract No. DE-NA0002378.

Anisotropic inflation with a non-minimally coupled electromagnetic field to gravity

NASA Astrophysics Data System (ADS)

Adak, Muzaffer; Akarsu, Özgür; Dereli, Tekin; Sert, Özcan

2017-11-01

We consider the non-minimal model of gravity in Y(R) F2-form. We investigate a particular case of the model, for which the higher order derivatives are eliminated but the scalar curvature R is kept to be dynamical via the constraint YRFmnFmn =-2/κ2. The effective fluid obtained can be represented by interacting electromagnetic field and vacuum depending on Y(R), namely, the energy density of the vacuum tracks R while energy density of the conventional electromagnetic field is dynamically scaled with the factor Y(R)/2. We give exact solutions for anisotropic inflation by assuming the volume scale factor of the Universe exhibits a power-law expansion. The directional scale factors do not necessarily exhibit power-law expansion, which would give rise to a constant expansion anisotropy, but expand non-trivially and give rise to a non-monotonically evolving expansion anisotropy that eventually converges to a non-zero constant. Relying on this fact, we discuss the anisotropic e-fold during the inflation by considering observed scale invariance in CMB and demanding the Universe to undergo the same amount of e-folds in all directions. We calculate the residual expansion anisotropy at the end of inflation, though as a result of non-monotonic behaviour of expansion anisotropy all the axes of the Universe undergo the same of amount of e-folds by the end of inflation. We also discuss the generation of the modified electromagnetic field during the first few e-folds of the inflation and its persistence against to the vacuum till end of inflation.

Plastic-bonded electrodes for nickel-cadmium accumulators. IV - Some specific problems of the positive active layer

NASA Astrophysics Data System (ADS)

Micka, K.; Mrha, J.; Klapste, B.

1980-06-01

The active layer of plastic-bonded nickel oxide electrodes undergoes expansion during discharging and contraction during charging; the latter however does not fully compensate for the expansion. These volume changes can be made reversible by the action of an external pressure. The electro-chemical behavior of the conductive components, carbon black and graphite, shows more or less severe corrosion during anodic current loading.

Getting Road Expansion on the Right Track: A Framework for Smart Infrastructure Planning in the Mekong

PubMed Central

Chen, Huafang; Phalan, Ben; Wang, Mingcheng; O’Connell, Christine; Tayleur, Cath

2016-01-01

The current unprecedented expansion of infrastructure promises to enhance human wellbeing but risks causing substantial harm to natural ecosystems and the benefits they provide for people. A framework for systematically and proactively identifying the likely benefits and costs of such developments is badly needed. Here, we develop and test at the subregional scale a recently proposed global scheme for comparing the potential gains from new roads for food production with their likely impact on biodiversity and ecosystem services. Working in the Greater Mekong—an exceptionally biodiverse subregion undergoing rapid development—we combined maps of isolation from urban centres, yield gaps, and the current area under 17 crops to estimate where and how far road development could in principle help to increase food production without the need for cropland expansion. We overlaid this information with maps summarising the importance of remaining habitats to terrestrial vertebrates and (as examples of major ecosystem services) to global and local climate regulation. This intersection revealed several largely converted yet relatively low-yielding areas (such as central, eastern, and northeastern Thailand and the Ayeyarwady Delta), where narrowing yield gaps by improving transport links has the potential to substantially increase food production at relatively limited environmental cost. Concentrating new roads and road improvements here while taking strong measures to prevent their spread into areas which are still extensively forested (such as northern Laos, western Yunnan, and southwestern Cambodia) could thus enhance rural livelihoods and regional food production while helping safeguard vital ecosystem services and globally significant biological diversity. PMID:27977663

Dissolved organic carbon export and its contribution to the carbon budget in a boreal peat landscape undergoing rapid permafrost thaw

NASA Astrophysics Data System (ADS)

Sonnentag, O.; Fouche, J.; Helbig, M.; Karoline, W.; Hould Gosselin, G.; Hanisch, J.; Quinton, W. L.; Moore, T. R.

2017-12-01

Northern permafrost soils store 1035 ± 150 Pg of organic carbon in the first 3 m. In boreal lowlands with warm and thin isolated, sporadic and discontinuous permafrost, increasing temperatures cause a thaw-induced expansion of permafrost-free wetlands at the expense of forested permafrost peat plateaus. Permafrost thaw associated with warmer soils may enhance microbial decomposition of near-surface and deeper organic matter but also increase dissolved organic carbon (DOC) export to aquatic systems. Recent studies suggest that, under a warmer climate, the current net CO2 sink strength of boreal peat landscapes may decline over the next few decades, eventually turning them into net CO2 sources. DOC export from these organic-rich landscapes undergoing rapid permafrost thaw may play a non-negligible role for the carbon budget in a warmer climate. In this study, we quantify the DOC export from a boreal peat landscape in the southern Northwest Territories (Canada). We use half-hourly discharge measurements and DOC concentrations sampled at the outlets of three small catchments ( 0.1 km2) to quantify runoff and DOC export from April to August 2014, 2015 and 2016. We estimate the DOC export contribution to the overall carbon budget using concurrent eddy covariance measurements of net CO2 and methane exchanges. The primary control of DOC export is discharge. In 2016, 70% of the DOC was exported during the two weeks of the spring freshet in early May. DOC export from the three catchments was 3g C m-2 from April to August, which accounted for 15% of the annual net ecosystem exchange. For the same period, the cumulative methane emissions were 6 g C-CH4 m-2. Our findings suggest that thawing boreal peat landscapes along the southern limit of permafrost currently act as net carbon sinks with 11 g C m-2 y-1. Investigating the optical properties of the dissolved organic matter across the different landforms (e.g., transition between forested permafrost peat plateau and permafrost-free wetland) will allow us to assess the different contributions to catchment DOC export and better forecast the changes in DOC lability with permafrost thaw and wetland expansion. Associated with a more rainfall-controlled runoff regime, changes in DOC export with warming may affect the carbon budget in the southern boundaries of the permafrost region.

Single-Pass, Closed-System Rapid Expansion of Lymphocyte Cultures for Adoptive Cell Therapy

PubMed Central

Klapper, Jacob A.; Thomasian, Armen A.; Smith, Douglas M.; Gorgas, Gayle C.; Wunderlich, John R.; Smith, Franz O.; Hampson, Brian S.; Rosenberg, Steven A.; Dudley, Mark E.

2009-01-01

Adoptive cell therapy (ACT) for metastatic melanoma involves the ex vivo expansion and re-infusion of tumor infiltrating lymphocytes (TIL) obtained from resected specimens. With an overall objective response rate of fifty-six percent, this T-cell immunotherapy provides an appealing alternative to other therapies, including conventional therapies with lower response rates. However, there are significant regulatory and logistical concerns associated with the ex vivo activation and large scale expansion of these cells. The best current practice uses a rapid expansion protocol (REP) consisting of an ex vivo process that occurs in tissue culture flasks (T-flasks) and gas-permeable bags, utilizes OKT3 (anti-CD3 monoclonal antibody), recombinant human interleukin-2, and irradiated peripheral blood mononuclear cells to initiate rapid lymphocyte growth. A major limitation to the widespread delivery of therapy to large numbers of melanoma patients is the open system in which a REP is initiated. To address this problem, we have investigated the initiation, expansion and harvest at clinical scale of TIL in a closed-system continuous perfusion bioreactor. Each cell product met all safety criteria for patient treatment and by head-to-head comparison had a similar potency and phenotype as cells grown in control T-flasks and gas-permeable bags. However, the currently available bioreactor cassettes were limited in the total cell numbers that could be generated. This bioreactor may simplify the process of the rapid expansion of TIL under stringent regulatory conditions thereby enabling other institutions to pursue this form of ACT. PMID:19389403

The evidence of the rugoscopy effectiveness as a human identification method in patients submitted to rapid palatal expansion.

PubMed

Barbieri, Ana A; Scoralick, Raquel A; Naressi, Suely C M; Moraes, Mari E L; Daruge, Eduardo; Daruge, Eduardo

2013-01-01

The objective of this study was to demonstrate the effectiveness of rugoscopy as a human identification method, even when the patient is submitted to rapid palatal expansion, which in theory would introduce doubt. With this intent, the Rugoscopic Identity was obtained for each subject using the classification formula proposed by Santos based on the intra-oral casts made before and after treatment from patients who were subjected to palatal expansion. The casts were labeled with the patients' initials and randomly arranged for studying. The palatine rugae kept the same patterns in every case studied. The technical error of the intra-evaluator measurement provided a confidence interval of 95%, making rugoscopy a reliable identification method for patients who were submitted to rapid palatal expansion, because even in the presence of intra-oral changes owing to the use of palatal expanders, the palatine rugae retained the biological and technical requirements for the human identification process. © 2012 American Academy of Forensic Sciences.

Use of conventional tomography to evaluate changes in the nasal cavity with rapid palatal expansion.

PubMed

Palaisa, Jacqueline; Ngan, Peter; Martin, Chris; Razmus, Thomas

2007-10-01

The relationship between nasal airway resistance and the use of rapid palatal expansion appliances remains controversial. The purpose of this study was to use conventional tomography to determine the anatomical changes in the nasal cavity after maxillary expansion. Nineteen patients (aged 8-15 years) were included in the study. Tomograms were taken before expansion (T1), immediately after expansion (T2), and 3 months after expansion (T3). Areas for the left and right anterior, middle, and posterior nasal cavity and total volume were calculated by using the computer software, AutoCAD LT 2005. Data were analyzed with paired t tests. Significant increases in area were found in the anterior nasal cavity from T1 to T2 (0.85 +/- 1.19 cm2, 11.7% increase), T2 to T3 (1.18 +/- 1.2 cm2, 22.2% increase), and T1 to T3 (2.6 +/- 1.7 cm2, 35.7% increase) (P <.05). Similar increases were found in the middle and posterior nasal cavity. Significant increases in volume were found from T1 to T2 (2.1 +/- 2.7 cm3, 10.7% increase), T2 to T3 (4.9 +/- 2.3 cm3, 22.6% increase), and T1 to T3 (6.99 +/- 2.45 cm3, 27.8% increase). No significant differences were found in the area or the volume of the left and right sides of the nasal cavity. Individual variations in response to maxillary expansion were large for most of the parameters tested. These data suggest that rapid palatal expansion is usually accompanied by increases in area and volume of the nasal cavity, and these changes remain stable 3 months after maxillary expansion.

Dynamics of vascular volume and hemodilution of lactated Ringer’s solution in patients during induction of general and epidural anesthesia*

PubMed Central

Li, Yu-hong; Lou, Xian-feng; Bao, Fang-ping

2006-01-01

Objective: To investigate the dynamics of vascular volume and the plasma dilution of lactated Ringer’s solution in patients during the induction of general and epidural anesthesia. Methods: The hemodilution of i.v. infusion of 1000 ml of lactated Ringer’s solution over 60 min was studied in patients undergoing general (n=31) and epidural (n=22) anesthesia. Heart rate, arterial blood pressure and hemoglobin (Hb) concentration were measured every 5 min during the study. Surgery was not started until the study period had been completed. Results: General anesthesia caused the greater decrease of mean arterial blood pressure (MAP) (mean 15% versus 9%; P<0.01) and thereby followed by a more pronounced plasma dilution, blood volume expansion (VE) and blood volume expansion efficiency (VEE). A strong linear correlation between hemodilution and the reduction in MAP (r=−0.50; P<0.01) was found. At the end of infusion, patients undergoing general anesthesia retained 47% (SD 19%) of the infused fluid in the circulation, while epidural anesthesia retained 29% (SD 13%) (P<0.001). Correspondingly, a fewer urine output (mean 89 ml versus 156 ml; P<0.05) and extravascular expansion (454 ml versus 551 ml; P<0.05) were found during general anesthesia. Conclusion: We concluded that the induction of general anesthesia caused more hemodilution, volume expansion and volume expansion efficiency than epidural anesthesia, which was triggered only by the lower MAP. PMID:16909476

Following Surgically Assisted Rapid Palatal Expansion, Do Tooth-Borne or Bone-Borne Appliances Provide More Skeletal Expansion and Dental Expansion?

PubMed

Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee

2017-10-01

The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P < .001) in favor of BB rather than TB appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Study of telomere length reveals rapid aging of human marrow stromal cells following in vitro expansion.

PubMed

Baxter, Melissa A; Wynn, Robert F; Jowitt, Simon N; Wraith, J Ed; Fairbairn, Leslie J; Bellantuono, Ilaria

2004-01-01

Human marrow stromal cells (MSCs) can be isolated from bone marrow and differentiate into multiple tissues in vitro and in vivo. These properties make them promising tools in cell and gene therapy. The lack of a specific MSC marker and the low frequency of MSCs in bone marrow necessitate their isolation by in vitro expansion prior to clinical use. This may severely reduce MSC proliferative capacity to the point that the residual proliferative potential is insufficient to maintain long-term tissue regeneration upon reinfusion. In this study we determined the effect of in vitro expansion on the replicative capacity of MSCs by correlating their rate of telomere loss during in vitro expansion with their behavior in vivo. We report that even protocols that involve minimal expansion induce a rapid aging of MSCs, with losses equivalent to about half their total replicative lifespan.

Glacial lake evolution in the southeastern Tibetan Plateau and the cause of rapid expansion of proglacial lakes linked to glacial-hydrogeomorphic processes

NASA Astrophysics Data System (ADS)

Song, Chunqiao; Sheng, Yongwei; Ke, Linghong; Nie, Yong; Wang, Jida

2016-09-01

Glacial lakes, as an important component of the cryosphere in the southeastern Tibetan Plateau (SETP) in response to climate change, pose significant threats to the downstream lives and properties of people, engineering construction, and ecological environment via outburst floods, yet we currently have limited knowledge of their distribution, evolution, and the driving mechanism of rapid expansions due to the low accessibility and harsh natural conditions. By integrating optical imagery, satellite altimetry and digital elevation model (DEM), this study presents a regional-scale investigation of glacial lake dynamics across two river basins of the SETP during 1988-2013 and further explores the glacial-hydrogeomorphic process of rapidly expanding lakes. In total 1278 and 1396 glacial lakes were inventoried in 1988 and 2013, respectively. Approximately 92.4% of the lakes in 2013 are not in contact with modern glaciers, and the remaining 7.6% includes 27 (1.9%) debris-contact lakes (in contact with debris-covered ice) and 80 (5.7%) cirque lakes. In categorizing lake variations, we found that debris-contact proglacial lakes experienced much more rapid expansions (∼75%) than cirque lakes (∼7%) and non-glacier-contact lakes (∼3%). To explore the cause of rapid expansion for these debris-contact lakes, we further investigated the mass balance of parent glaciers and elevation changes in lake surfaces and debris-covered glacier tongues using time-series Landsat images, ICESat altimetry, and DEM. Results reveal that the upstream expansion of debris-contact proglacial lakes was not directly associated with rising water levels but with a geomorphological alternation of upstream lake basins caused by melting-induced debris subsidence at glacier termini. This suggests that the hydrogeomorphic process of glacier thinning and retreat, in comparison with direct glacial meltwater alone, may have played a dominant role in the recent glacial lake expansion observed across the SETP. Our findings assist in understanding the expansion mechanism of debris-contact proglacial lakes, which facilitates early recognition of potential glacial lake hazards in this region.

Does Expansion Cause Congestion? The Case of the Older British Universities, 1994-2004

ERIC Educational Resources Information Center

Flegg, A. T.; Allen, D. O.

2007-01-01

This paper examines whether the rapid growth in the number of students in British universities in recent years has led to congestion, in the sense that certain universities' output could have been higher if this expansion had been less rapid. The focus of the paper is on 45 older universities that were in existence prior to 1992. The analysis…

The effects of micro-implant assisted rapid palatal expansion (MARPE) on the nasomaxillary complex--a finite element method (FEM) analysis.

PubMed

MacGinnis, Matt; Chu, Howard; Youssef, George; Wu, Kimberley W; Machado, Andre Wilson; Moon, Won

2014-08-29

Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion. A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software. The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex. In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth or maxillary complex.

Examination of rapid phase change in copper wires to improve material models and understanding of burst

NASA Astrophysics Data System (ADS)

Olles, Joseph; Garasi, Christopher; Ball, J. Patrick

2017-11-01

Electrically-pulsed wires undergo multiple phase changes including a postulated metastable phase resulting in explosive wire growth. Simulations using the MHD approximation attempt to account for the governing physics, but lack the material properties (equations-of-state and electrical conductivity) to accurately predict the phase evolution of the exploding (bursting) wire. To explore the dynamics of an exploding copper wire (in water), we employ a digital micro-Schlieren streak photography technique. This imaging quantifies wire expansion and shock waves emitted from the wire during phase changes. Using differential voltage probes, a Rogowski coil, and timing fiducials, the phase change of the wire is aligned with electrical power and energy deposition. Time-correlated electrical diagnostics and imaging allow for detailed validation of MHD simulations, comparing observed phases with phase change details found in the material property descriptions. In addition to streak imaging, a long exposure image is taken to capture axial striations along the length of the wire. These images are used to compare with results from 3D MHD simulations which propose that these perturbations impact the rate of wire expansion and temporal change in phases. If successful, the experimental data will identify areas for improvement in the material property models, and modeling results will provide insight into the details of phase change in the wire with correlation to variations in the electrical signals.

Intrinsic role of FoxO3a in the development of CD8+ T cell memory

PubMed Central

Tzelepis, Fanny; Joseph, Julie; Haddad, Elias K.; MacLean, Susanne; Dudani, Renu; Agenes, Fabien; Peng, Stanford L.; Sekaly, Rafick-Pierre; Sad, Subash

2013-01-01

CD8+ T cells undergo rapid expansion during infection with intracellular pathogens, which is followed by swift and massive culling of primed CD8+ T cells. The mechanisms that govern the massive contraction and maintenance of primed CD8+ T cells are not clear. We show here that the transcription factor, FoxO3a does not influence antigen-presentation and the consequent expansion of CD8+ T cell response during Listeria monocytogenes (LM) infection, but plays a key role in the maintenance of memory CD8+ T cells. The effector function of primed CD8+ T cells as revealed by cytokine secretion and CD107a degranulation was not influenced by inactivation of FoxO3a. Interestingly, FoxO3a-deficient CD8+ T cells displayed reduced expression of pro-apoptotic molecules BIM and PUMA during the various phases of response, and underwent reduced apoptosis in comparison to WT cells. A higher number of memory precursor effector cells (MPECs) and memory subsets were detectable in FoxO3a-deficient mice compared to WT mice. Furthermore, FoxO3a-deficient memory CD8+ T cells upon transfer into normal or RAG1-deficient mice displayed enhanced survival. These results suggest that FoxO3a acts in a cell intrinsic manner to regulate the survival of primed CD8+ T cells. PMID:23277488

Correction of complete maxillary crossbite with severe crowding using Hyrax expansion and fixed appliance.

PubMed

Wangsrimongkol, Tasanee; Manosudprasit, Montian; Pisek, Poonsak; Leelasinjaroen, Pornnapha

2013-09-01

An 18-year-old Thai man who presented with a secondary cleft palate, maxillary hypoplasia and severe crowding was treated by rapid maxillary expansion and fixed orthodontic appliances. Initial assessment found skeletal Class III malrelationship and dental Class II malocclusion with anterior and bilateral posterior crossbites. Camouflage orthodontic treatment was planned using a rapid maxillary expansion appliance and correcting crowding with extraction all four premolar teeth. A Hyrax appliance and vertical loop arch wire were placed for maxillary arch expansion of 9.5 mms at first molars and canines, and 5.5 mms at the premolars and obtained positive overjet. Both acceptable skeletal and soft tissue relationships and satisfactory occlusion were produced. After 14 months of postoperative follow-up, the occlusal result was stable and no skeletal reversals could be detected.

Flexibility transition and guest-driven reconstruction in a ferroelastic metal-organic framework†Electronic supplementary information (ESI) available: Atomic coordinates and lattice parameter data. CCDC 1016797. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4ce01572jClick here for additional data file.

PubMed

Hunt, Sarah J; Cliffe, Matthew J; Hill, Joshua A; Cairns, Andrew B; Funnell, Nicholas P; Goodwin, Andrew L

2015-01-14

The metal-organic framework copper(i) tricyanomethanide, Cu(tcm), undergoes a ferroelastic transition on cooling below T f = 240 K. Thermal expansion measurements reveal an order-of-magnitude variation in framework flexibility across T f . The low-temperature phase α-Cu(tcm) exhibits colossal positive and negative thermal expansion that is the strongest ever reported for a framework material. On exposure to acetonitrile, Cu(tcm) undergoes a reconstructive solid-phase transition to acetonitrilocopper(i) tricyanomethanide. This transition can be reversed by heating under vacuum. Infrared spectroscopy measurements are sensitive to the phase change, suggesting that Cu(tcm) may find application in solid-phase acetonitrile sensing.

Secretagogue stimulation of neurosecretory cells elicits filopodial extensions uncovering new functional release sites.

PubMed

Papadopulos, Andreas; Martin, Sally; Tomatis, Vanesa M; Gormal, Rachel S; Meunier, Frederic A

2013-12-04

Regulated exocytosis in neurosecretory cells relies on the timely fusion of secretory granules (SGs) with the plasma membrane. Secretagogue stimulation leads to an enlargement of the cell footprint (surface area in contact with the coverslip), an effect previously attributed to exocytic fusion of SGs with the plasma membrane. Using total internal reflection fluorescence microscopy, we reveal the formation of filopodia-like structures in bovine chromaffin and PC12 cells driving the footprint expansion, suggesting the involvement of cortical actin network remodeling in this process. Using exocytosis-incompetent PC12 cells, we demonstrate that footprint enlargement is largely independent of SG fusion, suggesting that vesicular exocytic fusion plays a relatively minor role in filopodial expansion. The footprint periphery, including filopodia, undergoes extensive F-actin remodeling, an effect abolished by the actomyosin inhibitors cytochalasin D and blebbistatin. Imaging of both Lifeact-GFP and the SG marker protein neuropeptide Y-mCherry reveals that SGs actively translocate along newly forming actin tracks before undergoing fusion. Together, these data demonstrate that neurosecretory cells regulate the number of SGs undergoing exocytosis during sustained stimulation by controlling vesicular mobilization and translocation to the plasma membrane through actin remodeling. Such remodeling facilitates the de novo formation of fusion sites.

Effects of climate change on forest vegetation in the Northern Rockies Region [Chapter 6

USGS Publications Warehouse

Keane, Robert E.; Mahalovich, Mary Frances; Bollenbacher, Barry L.; Manning, Mary E.; Loehman, Rachel A.; Jain, Terrie B.; Holsinger, Lisa M.; Larson, Andrew J.; Webster, Meredith M.

2018-01-01

The projected rapid changes in climate will affect the unique vegetation assemblages of the Northern Rockies region in myriad ways, both directly through shifts in vegetation growth, mortality, and regeneration, and indirectly through changes in disturbance regimes and interactions with changes in other ecosystem processes, such as hydrology, snow dynamics, and exotic invasions (Bonan 2008; Hansen and Phillips 2015; Hansen et al. 2001; Notaro et al. 2007). These impacts, taken collectively, could change the way vegetation is managed by public land agencies in this area. Some species may be in danger of rapid decreases in abundance, while others may undergo range expansion (Landhäusser et al. 2010). New vegetation communities may form, while historical vegetation complexes may simply shift to other areas of the landscape or become rare. Juxtaposed with climate change concerns are the consequences of other land management policies and past activities, such as fire exclusion, fuels treatments, and grazing. A thorough assessment of the responses of vegetation to projected climate change is needed, along with an evaluation of the vulnerability of important species, communities, and vegetation-related resources that may be influenced by the effects, both direct and indirect, of climate change. This assessment must also account for past management actions and current vegetation conditions and their interactions with future climates.

Rapid glass sponge expansion after climate-induced Antarctic ice shelf collapse.

PubMed

Fillinger, Laura; Janussen, Dorte; Lundälv, Tomas; Richter, Claudio

2013-07-22

Over 30% of the Antarctic continental shelf is permanently covered by floating ice shelves, providing aphotic conditions for a depauperate fauna sustained by laterally advected food. In much of the remaining Antarctic shallows (<300 m depth), seasonal sea-ice melting allows a patchy primary production supporting rich megabenthic communities dominated by glass sponges (Porifera, Hexactinellida). The catastrophic collapse of ice shelves due to rapid regional warming along the Antarctic Peninsula in recent decades has exposed over 23,000 km(2) of seafloor to local primary production. The response of the benthos to this unprecedented flux of food is, however, still unknown. In 2007, 12 years after disintegration of the Larsen A ice shelf, a first biological survey interpreted the presence of hexactinellids as remnants of a former under-ice fauna with deep-sea characteristics. Four years later, we revisited the original transect, finding 2- and 3-fold increases in glass sponge biomass and abundance, respectively, after only two favorable growth periods. Our findings, along with other long-term studies, suggest that Antarctic hexactinellids, locked in arrested growth for decades, may undergo boom-and-bust cycles, allowing them to quickly colonize new habitats. The cues triggering growth and reproduction in Antarctic glass sponges remain enigmatic. Copyright © 2013 Elsevier Ltd. All rights reserved.

Thermal Transients Excite Neurons through Universal Intramembrane Mechanoelectrical Effects

NASA Astrophysics Data System (ADS)

Plaksin, Michael; Shapira, Einat; Kimmel, Eitan; Shoham, Shy

2018-01-01

Modern advances in neurotechnology rely on effectively harnessing physical tools and insights towards remote neural control, thereby creating major new scientific and therapeutic opportunities. Specifically, rapid temperature pulses were shown to increase membrane capacitance, causing capacitive currents that explain neural excitation, but the underlying biophysics is not well understood. Here, we show that an intramembrane thermal-mechanical effect wherein the phospholipid bilayer undergoes axial narrowing and lateral expansion accurately predicts a potentially universal thermal capacitance increase rate of ˜0.3 % /°C . This capacitance increase and concurrent changes in the surface charge related fields lead to predictable exciting ionic displacement currents. The new MechanoElectrical Thermal Activation theory's predictions provide an excellent agreement with multiple experimental results and indirect estimates of latent biophysical quantities. Our results further highlight the role of electro-mechanics in neural excitation; they may also help illuminate subthreshold and novel physical cellular effects, and could potentially lead to advanced new methods for neural control.

Egr-5 is a post-mitotic regulator of planarian epidermal differentiation

PubMed Central

Tu, Kimberly C; Cheng, Li-Chun; TK Vu, Hanh; Lange, Jeffrey J; McKinney, Sean A; Seidel, Chris W; Sánchez Alvarado, Alejandro

2015-01-01

Neoblasts are an abundant, heterogeneous population of adult stem cells (ASCs) that facilitate the maintenance of planarian tissues and organs, providing a powerful system to study ASC self-renewal and differentiation dynamics. It is unknown how the collective output of neoblasts transit through differentiation pathways to produce specific cell types. The planarian epidermis is a simple tissue that undergoes rapid turnover. We found that as epidermal progeny differentiate, they progress through multiple spatiotemporal transition states with distinct gene expression profiles. We also identified a conserved early growth response family transcription factor, egr-5, that is essential for epidermal differentiation. Disruption of epidermal integrity by egr-5 RNAi triggers a global stress response that induces the proliferation of neoblasts and the concomitant expansion of not only epidermal, but also multiple progenitor cell populations. Our results further establish the planarian epidermis as a novel paradigm to uncover the molecular mechanisms regulating ASC specification in vivo. DOI: http://dx.doi.org/10.7554/eLife.10501.001 PMID:26457503

Reversible Calcium-Regulated Stopcocks in Legume Sieve TubesW⃞

PubMed Central

Knoblauch, Michael; Peters, Winfried S.; Ehlers, Katrin; van Bel, Aart J. E.

2001-01-01

Sieve tubes of legumes (Fabaceae) contain characteristic P-protein crystalloids with controversial function. We studied their behavior by conventional light, electron, and confocal laser scanning microscopy. In situ, crystalloids are able to undergo rapid (<1 sec) and reversible conversions from the condensed resting state into a dispersed state, in which they occlude the sieve tubes. Crystalloid dispersal is triggered by plasma membrane leakage induced by mechanical injury or permeabilizing substances. Similarly, abrupt turgor changes imposed by osmotic shock cause crystalloid dispersal. Because chelators generally prevent the response, divalent cations appear to be the decisive factor in crystalloid expansion. Cycling between dispersal and condensation can be induced in opened cells by repetitive exchange of bathing media containing either Ca2+ or chelators. Sr2+ and Ba2+, but not Mg2+, are equally active. In conclusion, the fabacean P-protein crystalloids represent a novel class of mechanically active proteinaceous structures, which provide an efficient mechanism with which to control sieve tube conductivity. PMID:11340193

Focused Study of Thermonuclear Bursts on Neutron Stars

NASA Astrophysics Data System (ADS)

Chenevez, Jérôme

2009-05-01

X-ray bursters form a class of Low Mass X-Ray Binaries where accreted material from a donor star undergoes rapid thermonuclear burning in the surface layers of a neutron star. The flux released can temporarily exceed the Eddington limit and drive the photosphere to large radii. Such photospheric radius expansion bursts likely eject nuclear burning ashes into the interstellar medium, and may make possible the detection of photoionization edges. Indeed, theoretical models predict that absorption edges from 58Fe at 9.2 keV, 60Zn and 62Zn at 12.2 keV should be detectable by the future missions Simbol-X and NuSTAR. A positive detection would thus probe the nuclear burning as well as the gravitational redshift from the neutron star. Moreover, likely observations of atomic X-ray spectral components reflected from the inner accretion disk have been reported. The high spectral resolution capabilities of the focusing X-ray telescopes may therefore make possible to differentiate between the potential interpretations of the X-ray bursts spectral features.

A Method for Extracting Pigments from Squid Doryteuthis pealeii.

PubMed

DiBona, Christopher W; Williams, Thomas L; Dinneen, Sean R; Jones Labadie, Stephanie F; Deravi, Leila F

2016-11-09

Cephalopods can undergo rapid and adaptive changes in dermal coloration for sensing, communication, defense, and reproduction purposes. These capabilities are supported in part by the areal expansion and retraction of pigmented organs known as chromatophores. While it is known that the chromatophores contain a tethered network of pigmented granules, their structure-function properties have not been fully detailed. We describe a method for isolating the nanostructured granules in squid Doryteuthis pealeii chromatophores and demonstrate how their associated pigments can be extracted in acidic solvents. To accomplish this, the chromatophore containing dermal layer is first manually isolated using a superficial dissection, and the pigment granules are removed using sonication, centrifugation, and washing cycles. Pigments confined within the purified granules are then extracted via acidic methanol solutions, leaving nanostructures with smaller diameters that are void of visible color. This extraction procedure produces a 58% yield of soluble pigments isolated from granules. Using this method, the composition of the chromatophore pigments can be determined and used to provide insight into the mechanism of adaptive coloration in cephalopods.

Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].

DOT National Transportation Integrated Search

2014-12-01

This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.

A System Dynamics Model for Long-Term Planning of the Undergraduate Education in Brazil

ERIC Educational Resources Information Center

Strauss, Luísa Mariele; Borenstein, Denis

2015-01-01

Higher education in Brazil has experienced a rapid expansion since the 1990s as a consequence of the government's pliability in launching new programs and educational institutions. This expansion was mainly driven by the private sector. Despite this expansion, Brazil has not yet achieved the enrollment goal expected in the National Education Plan…

Rapid adaptation to climate facilitates range expansion of an invasive plant.

PubMed

Colautti, Robert I; Barrett, Spencer C H

2013-10-18

Adaptation to climate, evolving over contemporary time scales, could facilitate rapid range expansion across environmental gradients. Here, we examine local adaptation along a climatic gradient in the North American invasive plant Lythrum salicaria. We show that the evolution of earlier flowering is adaptive at the northern invasion front where it increases fitness as much as, or more than, the effects of enemy release and the evolution of increased competitive ability. However, early flowering decreases investment in vegetative growth, which reduces fitness by a factor of 3 in southern environments where the North American invasion commenced. Our results demonstrate that local adaptation can evolve quickly during range expansion, overcoming environmental constraints on propagule production.

Assessing the impacts of dams and levees on the hydrologic record of the Middle and Lower Mississippi River, USA

USGS Publications Warehouse

Remo, Jonathan W.F.; Ickes, Brian; Ryherd, Julia K.; Guida, Ross J.; Therrell, Matthew D.

2018-01-01

The impacts of dams and levees on the long-term (>130 years) discharge record was assessed along a ~1200 km segment of the Mississippi River between St. Louis, Missouri, and Vicksburg, Mississippi. To aid in our evaluation of dam impacts, we used data from the U.S. National Inventory of Dams to calculate the rate of reservoir expansion at five long-term hydrologic monitoring stations along the study segment. We divided the hydrologic record at each station into three periods: (1) a pre-rapid reservoir expansion period; (2) a rapid reservoir expansion period; and (3) a post-rapid reservoir expansion period. We then used three approaches to assess changes in the hydrologic record at each station. Indicators of hydrologic alteration (IHA) and flow duration hydrographs were used to quantify changes in flow conditions between the pre- and post-rapid reservoir expansion periods. Auto-regressive interrupted time series analysis (ARITS) was used to assess trends in maximum annual discharge, mean annual discharge, minimum annual discharge, and standard deviation of daily discharges within a given water year. A one-dimensional HEC-RAS hydraulic model was used to assess the impact of levees on flood flows. Our results revealed that minimum annual discharges and low-flow IHA parameters showed the most significant changes. Additionally, increasing trends in minimum annual discharge during the rapid reservoir expansion period were found at three out of the five hydrologic monitoring stations. These IHA and ARITS results support previous findings consistent with the observation that reservoirs generally have the greatest impacts on low-flow conditions. River segment scale hydraulic modeling revealed levees can modestly increase peak flood discharges, while basin-scale hydrologic modeling assessments by the U.S. Army Corps of Engineers showed that tributary reservoirs reduced peak discharges by a similar magnitude (2 to 30%). This finding suggests that the effects of dams and levees on peak flood discharges are in part offsetting one another along the modeled river segments and likely other substantially leveed segments of the Mississippi River.

Assessing the impacts of dams and levees on the hydrologic record of the Middle and Lower Mississippi River, USA

NASA Astrophysics Data System (ADS)

Remo, Jonathan W. F.; Ickes, Brian S.; Ryherd, Julia K.; Guida, Ross J.; Therrell, Matthew D.

2018-07-01

The impacts of dams and levees on the long-term (>130 years) discharge record was assessed along a 1200 km segment of the Mississippi River between St. Louis, Missouri, and Vicksburg, Mississippi. To aid in our evaluation of dam impacts, we used data from the U.S. National Inventory of Dams to calculate the rate of reservoir expansion at five long-term hydrologic monitoring stations along the study segment. We divided the hydrologic record at each station into three periods: (1) a pre-rapid reservoir expansion period; (2) a rapid reservoir expansion period; and (3) a post-rapid reservoir expansion period. We then used three approaches to assess changes in the hydrologic record at each station. Indicators of hydrologic alteration (IHA) and flow duration hydrographs were used to quantify changes in flow conditions between the pre- and post-rapid reservoir expansion periods. Auto-regressive interrupted time series analysis (ARITS) was used to assess trends in maximum annual discharge, mean annual discharge, minimum annual discharge, and standard deviation of daily discharges within a given water year. A one-dimensional HEC-RAS hydraulic model was used to assess the impact of levees on flood flows. Our results revealed that minimum annual discharges and low-flow IHA parameters showed the most significant changes. Additionally, increasing trends in minimum annual discharge during the rapid reservoir expansion period were found at three out of the five hydrologic monitoring stations. These IHA and ARITS results support previous findings consistent with the observation that reservoirs generally have the greatest impacts on low-flow conditions. River segment scale hydraulic modeling revealed levees can modestly increase peak flood discharges, while basin-scale hydrologic modeling assessments by the U.S. Army Corps of Engineers showed that tributary reservoirs reduced peak discharges by a similar magnitude (2 to 30%). This finding suggests that the effects of dams and levees on peak flood discharges are in part offsetting one another along the modeled river segments and likely other substantially leveed segments of the Mississippi River.

Transverse changes determined by rapid and slow maxillary expansion--a low-dose CT-based randomized controlled trial.

PubMed

Martina, R; Cioffi, I; Farella, M; Leone, P; Manzo, P; Matarese, G; Portelli, M; Nucera, R; Cordasco, G

2012-08-01

To compare transverse skeletal changes produced by rapid (RME) and slow (SME) maxillary expansion using low-dose computed tomography. The null hypothesis was that SME and RME are equally effective in producing skeletal maxillary expansion in patients with posterior crossbite. This study was carried out at the Department of Oral Sciences, University of Naples Federico II, Italy. Twelve patients (seven males, five females, mean age ± SD: 10.3 ± 2.5 years) were allocated to the SME group and 14 patients (six males, eight females, mean age ± SD: 9.7 ± 1.5 years) to the RME group. All patients received a two-band palatal expander and were randomly allocated to either RME or SME. Low-dose computed tomography was used to identify skeletal and dental landmarks and to measure transverse maxillary changes with treatment. A significant increase in skeletal transverse diameters was found in both SME and RME groups (anterior expansion = 2.2 ± 1.4 mm, posterior expansion = 2.2 ± 0.9 mm, pterygoid expansion = 0.9 ± 0.8 mm). No significant differences were found between groups at anterior (SME = 1.9 ± 1.3 mm; RME = 2.5 ± 1.5 mm) or posterior (SME = 1.9 ± 1.0 mm; RME = 2.4 ± 0.9 mm) locations, while a statistically significant difference was measured at the pterygoid processes (SME = 0.6 ± 0.6 mm; RME = 1.2 ± 0.9 mm, p = 0.04), which was not clinically relevant. Rapid maxillary expansion is not more effective than SME in expanding the maxilla in patients with posterior crossbite. © 2012 John Wiley & Sons A/S.

Model test on partial expansion in stratified subsidence during foundation pit dewatering

NASA Astrophysics Data System (ADS)

Wang, Jianxiu; Deng, Yansheng; Ma, Ruiqiang; Liu, Xiaotian; Guo, Qingfeng; Liu, Shaoli; Shao, Yule; Wu, Linbo; Zhou, Jie; Yang, Tianliang; Wang, Hanmei; Huang, Xinlei

2018-02-01

Partial expansion was observed in stratified subsidence during foundation pit dewatering. However, the phenomenon was suspected to be an error because the compression of layers is known to occur when subsidence occurs. A slice of the subsidence cone induced by drawdown was selected as the prototype. Model tests were performed to investigate the phenomenon. The underlying confined aquifer was generated as a movable rigid plate with a hinge at one end. The overlying layers were simulated with remolded materials collected from a construction site. Model tests performed under the conceptual model indicated that partial expansion occurred in stratified settlements under coordination deformation and consolidation conditions. During foundation pit dewatering, rapid drawdown resulted in rapid subsidence in the dewatered confined aquifer. The rapidly subsiding confined aquifer top was the bottom deformation boundary of the overlying layers. Non-coordination deformation was observed at the top and bottom of the subsiding overlying layers. The subsidence of overlying layers was larger at the bottom than at the top. The layers expanded and became thicker. The phenomenon was verified using numerical simulation method based on finite difference method. Compared with numerical simulation results, the boundary effect of the physical tests was obvious in the observation point close to the movable endpoint. The tensile stress of the overlying soil layers induced by the underlying settlement of dewatered confined aquifer contributed to the expansion phenomenon. The partial expansion of overlying soil layers was defined as inversed rebound. The inversed rebound was induced by inversed coordination deformation. Compression was induced by the consolidation in the overlying soil layers because of drainage. Partial expansion occurred when the expansion exceeded the compression. Considering the inversed rebound, traditional layer-wise summation method for calculating subsidence should be revised and improved.

Linear analysis using secants for materials with temperature dependent nonlinear elastic modulus and thermal expansion properties

NASA Astrophysics Data System (ADS)

Pepi, John W.

2017-08-01

Thermally induced stress is readily calculated for linear elastic material properties using Hooke's law in which, for situations where expansion is constrained, stress is proportional to the product of the material elastic modulus and its thermal strain. When material behavior is nonlinear, one needs to make use of nonlinear theory. However, we can avoid that complexity in some situations. For situations in which both elastic modulus and coefficient of thermal expansion vary with temperature, solutions can be formulated using secant properties. A theoretical approach is thus presented to calculate stresses for nonlinear, neo-Hookean, materials. This is important for high acuity optical systems undergoing large temperature extremes.

Differential Higgs production at N3LO beyond threshold

NASA Astrophysics Data System (ADS)

Dulat, Falko; Mistlberger, Bernhard; Pelloni, Andrea

2018-01-01

We present several key steps towards the computation of differential Higgs boson cross sections at N3LO in perturbative QCD. Specifically, we work in the framework of Higgs-differential cross sections that allows to compute precise predictions for realistic LHC observables. We demonstrate how to perform an expansion of the analytic N3LO coefficient functions around the production threshold of the Higgs boson. Our framework allows us to compute to arbitrarily high order in the threshold expansion and we explicitly obtain the first two expansion coefficients in analytic form. Furthermore, we assess the phenomenological viability of threshold expansions for differential distributions. We find that while a few terms in the threshold expansion are sufficient to approximate the exact rapidity distribution well, transverse momentum distributions require a signficantly higher number of terms in the expansion to be adequately described. We find that to improve state of the art predictions for the rapidity distribution beyond NNLO even more sub-leading terms in the threshold expansion than presented in this article are required. In addition, we report on an interesting obstacle for the computation of N3LO corrections with LHAPDF parton distribution functions and our solution. We provide files containing the analytic expressions for the partonic cross sections as supplementary material attached to this paper.

Differential Higgs production at N 3LO beyond threshold

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

Dulat, Falko; Mistlberger, Bernhard; Pelloni, Andrea

We present several key steps towards the computation of differential Higgs boson cross sections at N 3LO in perturbative QCD. Specifically, we work in the framework of Higgs-differential cross sections that allows to compute precise predictions for realistic LHC observables. We demonstrate how to perform an expansion of the analytic N 3LO coefficient functions around the production threshold of the Higgs boson. Our framework allows us to compute to arbitrarily high order in the threshold expansion and we explicitly obtain the first two expansion coefficients in analytic form. Furthermore, we assess the phenomenological viability of threshold expansions for differential distributions.more » We find that while a few terms in the threshold expansion are sufficient to approximate the exact rapidity distribution well, transverse momentum distributions require a signficantly higher number of terms in the expansion to be adequately described. We find that to improve state of the art predictions for the rapidity distribution beyond NNLO even more sub-leading terms in the threshold expansion than presented in this article are required. In addition, we report on an interesting obstacle for the computation of N 3LO corrections with LHAPDF parton distribution functions and our solution. We provide files containing the analytic expressions for the partonic cross sections as supplementary material attached to this paper.« less

Differential Higgs production at N 3LO beyond threshold

DOE PAGES

Dulat, Falko; Mistlberger, Bernhard; Pelloni, Andrea

2018-01-29

We present several key steps towards the computation of differential Higgs boson cross sections at N 3LO in perturbative QCD. Specifically, we work in the framework of Higgs-differential cross sections that allows to compute precise predictions for realistic LHC observables. We demonstrate how to perform an expansion of the analytic N 3LO coefficient functions around the production threshold of the Higgs boson. Our framework allows us to compute to arbitrarily high order in the threshold expansion and we explicitly obtain the first two expansion coefficients in analytic form. Furthermore, we assess the phenomenological viability of threshold expansions for differential distributions.more » We find that while a few terms in the threshold expansion are sufficient to approximate the exact rapidity distribution well, transverse momentum distributions require a signficantly higher number of terms in the expansion to be adequately described. We find that to improve state of the art predictions for the rapidity distribution beyond NNLO even more sub-leading terms in the threshold expansion than presented in this article are required. In addition, we report on an interesting obstacle for the computation of N 3LO corrections with LHAPDF parton distribution functions and our solution. We provide files containing the analytic expressions for the partonic cross sections as supplementary material attached to this paper.« less

Regioselective SN2 reactions for rapid syntheses of azido-inositols by one-pot sequence-specific nucleophilysis.

PubMed

Ravi, Arthi; Hassan, Syed Zahid; Vanikrishna, Ajithkumar N; Sureshan, Kana M

2017-04-04

Triflates of myo-inositol undergo facile solvolysis in DMSO and DMF yielding S N 2 products substituted with O-nucleophiles; DMF showed slower kinetics. Axial O-triflate undergoes faster substitution than equatorial O-triflate. By exploiting this difference in kinetics, solvent-tuning and sequence-controlled nucleophilysis, rapid synthesis of three azido-inositols of myo-configuration from myo-inositol itself has been achieved.

Ecotype-specific and chromosome-specific expansion of variant centromeric satellites in Arabidopsis thaliana.

PubMed

Ito, Hidetaka; Miura, Asuka; Takashima, Kazuya; Kakutani, Tetsuji

2007-01-01

Despite the conserved roles and conserved protein machineries of centromeres, their nucleotide sequences can be highly diverse even among related species. The diversity reflects rapid evolution, but the underlying mechanism is largely unknown. One approach to monitor rapid evolution is examination of intra-specific variation. Here we report variant centromeric satellites of Arabidopsis thaliana found through survey of 103 natural accessions (ecotypes). Among them, a cluster of variant centromeric satellites was detected in one ecotype, Cape Verde Islands (Cvi). Recombinant inbred mapping revealed that the variant satellites are distributed in centromeric region of the chromosome 5 (CEN5) of this ecotype. This apparently recent variant accumulation is associated with large deletion of a pericentromeric region and the expansion of satellite region. The variant satellite was bound to HTR12 (centromeric variant histone H3), although expansion of the satellite was not associated with comparable increase in the HTR12 binding. The results suggest that variant satellites with centromere function can rapidly accumulate in one centromere, supporting the model that the satellite repeats in the array are homogenized by occasional unequal crossing-over, which has a potential to generate an expansion of local sequence variants within a centromere cluster.

Discordant introgression in a rapidly expanding hybrid swarm

USGS Publications Warehouse

Ward, Jessica L.; Blum, Mike J.; Walters, David M.; Porter, Brady A.; Burkhead, Noel; Freeman, Byron

2012-01-01

The erosion of species boundaries can involve rapid evolutionary change. Consequently, many aspects of the process remain poorly understood, including the formation, expansion, and evolution of hybrid swarms. Biological invasions involving hybridization present exceptional opportunities to study the erosion of species boundaries because timelines of interactions and outcomes are frequently well known. Here, we examined clinal variation across codominant and maternally inherited genetic markers as well as phenotypic traits to characterize the expansion and evolution of a hybrid swarm between native Cyprinella venusta and invasive Cyprinella lutrensis minnows. Discordant introgression of phenotype, microsatellite multilocus genotype, and mtDNA haplotype indicates that the observable expansion of the C. venusta x C. lutrensis hybrid swarm is a false invasion front. Both parental and hybrid individuals closely resembling C. lutrensis are numerically dominant in the expansion wake, indicating that the non-native parental phenotype may be selectively favored. These findings show that cryptic introgression can extend beyond the phenotypic boundaries of hybrid swarms and that hybrid swarms likely expand more rapidly than can be documented from phenotypic variation alone. Similarly, dominance of a single parental phenotype following an introduction event may lead to instances of species erosion being mistaken for species displacement without hybridization.

What are estimated reimbursements for lower extremity prostheses capable of surgical and nonsurgical lengthening?

PubMed

Henderson, Eric R; Pepper, Andrew M; Letson, G Douglas

2012-04-01

Growing prostheses accommodate skeletally immature patients with bone tumors undergoing limb-preserving surgery. Early devices required surgical procedures for lengthening; recent devices lengthen without surgery. Expenses for newer expandable devices that lengthen without surgery are more than for their predecessors but overall reimbursement amounts are not known. We sought to determine reimbursement amounts associated with lengthening of growing prostheses requiring surgical and nonsurgical lengthening. We retrospectively reviewed 17 patients with growing prostheses requiring surgical expansion and eight patients with prostheses capable of nonsurgical expansion. Insurance documents were reviewed to determine the reimbursement for implantation, lengthening, and complications. Growth data were obtained from the literature. Mean reimbursement amounts of surgical and nonsurgical lengthenings were $9950 and $272, respectively. Estimated reimbursements associated with implantation of a growing prosthesis varied depending on age, sex, and location. The largest difference was found for 4-year-old boys with distal femoral replacement where reimbursement for expansion to maturity for surgical and nonsurgical lengthening prostheses would be $379,000 and $208,000, respectively. For children requiring more than one surgical expansion, net reimbursements were lower when a noninvasive lengthening device was used. Annual per-prosthesis maintenance reimbursements to address complications for surgical and nonsurgical lengthening prostheses were $3386 and $1856, respectively. This study showed that reimbursements for lengthening of growing endoprostheses capable of nonsurgical expansion may be less expensive in younger patients, particularly male patients undergoing distal femur replacement, than endoprostheses requiring surgical lengthening. Longer outcomes studies are required to see if reimbursements for complications differ between devices. Level III, economic and decision analysis. See the Guidelines for Authors for a complete description of levels of evidence.

Immediate periodontal bone plate changes induced by rapid maxillary expansion in the early mixed dentition: CT findings

PubMed Central

Garib, Daniela Gamba; Menezes, Maria Helena Ocké; da Silva Filho, Omar Gabriel; dos Santos, Patricia Bittencourt Dutra

2014-01-01

Objective This study aimed at evaluating buccal and lingual bone plate changes caused by rapid maxillary expansion (RME) in the mixed dentition by means of computed tomography (CT). Methods The sample comprised spiral CT exams taken from 22 mixed dentition patients from 6 to 9 years of age (mean age of 8.1 years) presenting constricted maxillary arch treated with Haas-type expanders. Patients were submitted to spiral CT scan before expansion and after the screw activation period with a 30-day interval between T1 and T2. Multiplanar reconstruction was used to measure buccal and lingual bone plate thickness and buccal bone crest level of maxillary posterior deciduous and permanent teeth. Changes induced by expansion were evaluated using paired t test (p < 0.05). Results Thickness of buccal and lingual bone plates of posterior teeth remained unchanged during the expansion period, except for deciduous second molars which showed a slight reduction in bone thickness at the distal region of its buccal aspect. Buccal bone dehiscences were not observed in the supporting teeth after expansion. Conclusion RME performed in mixed dentition did not produce immediate undesirable effects on periodontal bone tissues. PMID:25162564

Anisotropic Bianchi-V dark energy model under the new perspective of accelerated expansion of the universe in Brans-Dicke theory of gravitation

NASA Astrophysics Data System (ADS)

Jaiswal, Rekha; Zia, Rashid

2018-04-01

In this paper, we have proposed a cosmological model, which is consistent with the new findings of `The Supernova Cosmology project' headed by Saul Perlmutter, and the `High-Z Supernova Search team', headed by Brian Schimdt. According to these new findings, the universe is undergoing an expansion with an increasing rate, in contrast to the earlier belief that the rate of expansion is constant or the expansion is slowing down. We have considered spatially homogeneous and anisotropic Bianchi-V dark energy model in Brans-Dicke theory of gravitation. We have taken the scale factor a(t)=k t^α e^{β t} , which results into variable deceleration parameter (DP). The graph of DP shows a transition from positive to negative, which shows that universe has passed through the past decelerated expansion to the current accelerated expansion phase. In this context, we have also calculated and plotted various parameters and observed that these are in good agreement with physical and kinematic properties of the universe and are also consistent with recent observations.

Dendritic cells control fibroblastic reticular network tension and lymph node expansion.

PubMed

Acton, Sophie E; Farrugia, Aaron J; Astarita, Jillian L; Mourão-Sá, Diego; Jenkins, Robert P; Nye, Emma; Hooper, Steven; van Blijswijk, Janneke; Rogers, Neil C; Snelgrove, Kathryn J; Rosewell, Ian; Moita, Luis F; Stamp, Gordon; Turley, Shannon J; Sahai, Erik; Reis e Sousa, Caetano

2014-10-23

After immunogenic challenge, infiltrating and dividing lymphocytes markedly increase lymph node cellularity, leading to organ expansion. Here we report that the physical elasticity of lymph nodes is maintained in part by podoplanin (PDPN) signalling in stromal fibroblastic reticular cells (FRCs) and its modulation by CLEC-2 expressed on dendritic cells. We show in mouse cells that PDPN induces actomyosin contractility in FRCs via activation of RhoA/C and downstream Rho-associated protein kinase (ROCK). Engagement by CLEC-2 causes PDPN clustering and rapidly uncouples PDPN from RhoA/C activation, relaxing the actomyosin cytoskeleton and permitting FRC stretching. Notably, administration of CLEC-2 protein to immunized mice augments lymph node expansion. In contrast, lymph node expansion is significantly constrained in mice selectively lacking CLEC-2 expression in dendritic cells. Thus, the same dendritic cells that initiate immunity by presenting antigens to T lymphocytes also initiate remodelling of lymph nodes by delivering CLEC-2 to FRCs. CLEC-2 modulation of PDPN signalling permits FRC network stretching and allows for the rapid lymph node expansion--driven by lymphocyte influx and proliferation--that is the critical hallmark of adaptive immunity.

Program and charts for determining shock tube, and expansion tunnel flow quantities for real air

NASA Technical Reports Server (NTRS)

Miller, C. G., III; Wilder, S. E.

1975-01-01

A computer program in FORTRAN 4 language was written to determine shock tube, expansion tube, and expansion tunnel flow quantities for real-air test gas. This program permits, as input data, a number of possible combinations of flow quantities generally measured during a test. The versatility of the program is enhanced by the inclusion of such effects as a standing or totally reflected shock at the secondary diaphragm, thermochemical-equilibrium flow expansion and frozen flow expansion for the expansion tube and expansion tunnel, attenuation of the flow in traversing the acceleration section of the expansion tube, real air as the acceleration gas, and the effect of wall boundary layer on the acceleration section air flow. Charts which provide a rapid estimation of expansion tube performance prior to a test are included.

Condyle fossa relationship associated with functional posterior crossbite, before and after rapid maxillary expansion.

PubMed

Leonardi, Rosalia; Caltabiano, Mario; Cavallini, Costanza; Sicurezza, Edoardo; Barbato, Ersilia; Spampinato, Concetto; Giordano, Daniela

2012-11-01

To investigate condylar symmetry and condyle fossa relationships in subjects with functional posterior crossbite comparing findings before and after rapid maxillary expansion (RME) treatment through low-dose computed tomography (CT). Twenty-six patients (14 girls and 12 boys, mean age 9.6 ± 1.4 years) with functional posterior crossbite (FPXB) diagnosis underwent rapid palatal expansion with a Hyrax appliance. Patients' temporomandibular joints (TMJ) underwent multislice CT scans before rapid palatal expansion (T0) and after (T1). Joint spaces were compared with those of a control sample of 13 subjects (7 girls and 5 boys, mean age 11 ± 0.6 years). Anterior space (AS), superior space (SS), and posterior space (PS) joint space measurements at T0 between the FPXB side and contralateral side demonstrated no statistically significant differences. After RME treatment (T1), all three joint spaces increased on both the FPXB side and the non-crossbite side. However, differences were statistically significant only for the SS when comparing the two sides at T1. SS increased more than AS and PS in the non-crossbite condyle (0.28 mm) and FPXB condyle (0.37 mm), and PS increased only on the FPXB side (0.34 mm). There were no statistically significant differences in condyle position within the glenoid fossa between the FPXB and non-crossbite side before treatment. Increases in joint spaces were observed after treatment with RME on both sides. These changes were, however, of small amounts.

Non-surgical treatment of transverse deficiency in adults using Microimplant-assisted Rapid Palatal Expansion (MARPE)

PubMed Central

Brunetto, Daniel Paludo; Sant’Anna, Eduardo Franzzotti; Machado, Andre Wilson; Moon, Won

2017-01-01

ABSTRACT Introduction: Maxillary transverse deficiency is a highly prevalent malocclusion present in all age groups, from primary to permanent dentition. If not treated on time, it can aggravate and evolve to a more complex malocclusion, hindering facial growth and development. Aside from the occlusal consequences, the deficiency can bring about serious respiratory problems as well, due to the consequent nasal constriction usually associated. In growing patients, this condition can be easily handled with a conventional rapid palatal expansion. However, mature patients are frequently subjected to a more invasive procedure, the surgically-assisted rapid palatal expansion (SARPE). More recently, researches have demonstrated that it is possible to expand the maxilla in grown patients without performing osteotomies, but using microimplants anchorage instead. This novel technique is called microimplant-assisted rapid palatal expansion (MARPE). Objective: The aim of the present article was to demonstrate and discuss a MARPE technique developed by Dr. Won Moon and colleagues at University of California - Los Angeles (UCLA). Methods: All laboratory and clinical steps needed for its correct execution are thoroughly described. For better comprehension, a mature patient case is reported, detailing all the treatment progress and results obtained. Conclusion: It was concluded that the demonstrated technique could be an interesting alternative to SARPE in the majority of non-growing patients with maxillary transverse deficiency. The present patient showed important occlusal and respiratory benefits following the procedure, without requiring any surgical intervention. PMID:28444019

Rapid maxillary expansion for pediatric obstructive sleep apnea: A systematic review and meta-analysis.

PubMed

Camacho, Macario; Chang, Edward T; Song, Sungjin A; Abdullatif, Jose; Zaghi, Soroush; Pirelli, Paola; Certal, Victor; Guilleminault, Christian

2017-07-01

To perform a systematic review with meta-analysis for sleep study outcomes in children who have undergone rapid maxillary expansion (RME) as treatment for obstructive sleep apnea (OSA). PubMed/MEDLINE and eight additional databases. Three authors independently and systematically reviewed the international literature through February 21, 2016. Seventeen studies reported outcomes for 314 children (7.6 ± 2.0 years old) with high-arched and/or narrow hard palates (transverse maxillary deficiency) and OSA. Data were analyzed based on follow-up duration: ≤3 years (314 patients) and >3 years (52 patients). For ≤3-year follow-up, the pre- and post-RME apnea-hypopnea index (AHI) decreased from a mean ± standard deviation (M ± SD) of 8.9 ± 7.0/hr to 2.7 ± 3.3/hr (70% reduction). The cure rate (AHI <1/hr) for 90 patients for whom it could be calculated was 25.6%. Random effects modeling for AHI standardized mean difference (SMD) is -1.54 (large effect). Lowest oxygen saturation (LSAT) improved from 87.0 ± 9.1% to 96.0 ± 2.7%. Random effects modeling for LSAT SMD is 1.74 (large effect). AHI improved more in children with previous adenotonsillectomy or small tonsils (73-95% reduction) than in children with large tonsils (61% reduction). For >3-year follow-up (range = 6.5-12 years), the AHI was reduced from an M ± SD of 7.1 ± 5.7/hr to 1.5 ± 1.8/hr (79% reduction). Improvement in AHI and lowest oxygen saturation has consistently been seen in children undergoing RME, especially in the short term (<3-year follow-up). Randomized trials and more studies reporting long-term data (≥3-year follow-up) would help determine the effect of growth and spontaneous resolution of OSA. Laryngoscope, 2016 Laryngoscope, 127:1712-1719, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Effect of Rapid Maxillary Expansion on Glenoid Fossa and Condyle-Fossa Relationship in Growing Patients (MEGP): Study Protocol for a Controlled Clinical Trial

PubMed Central

Ghoussoub, Mona Sayegh; Rifai, Khaldoun; Garcia, Robert; Sleilaty, Ghassan

2018-01-01

Aims and Objectives: Rapid maxillary expansion (RME) is an orthodontic nonsurgical procedure aiming at increasing the width of the maxilla by opening mainly the intermaxillary suture in patients presenting a transverse maxillary skeletal deficiency. The objectives of the current prospective controlled clinical and radiographic study are to evaluate the hypothesis that RME in growing patients will result in radiographic changes at the level of interglenoid fossa distance, condyle-fossa relationship, and nasal cavity widths compared to the group who received no treatment initially and served as untreated control. Materials and Methods: In this prospective controlled clinical and radiographic study, forty healthy growing patients selected from a school-based population following a large screening campaign, ranging in age between 8 and 13 years, presenting a maxillary constriction with bilateral crossbite, and candidates for RME are being recruited. The first group will include participants willing to undergo treatment (n = 25) and the other group will include those inclined to postpone (n = 15). Results: The primary outcome is to compare radiologically the interglenoid fossa distance and the condyle-fossa relationship; nasal cavity width will be a secondary outcome. A multivariable analysis of Covariance model will be used, with the assessment of the time by group interaction, using age as covariate. The project protocol was reviewed and approved by the Ethics Committee of the Lebanese University, National Institute in Lebanon (CUEMB process number 31/04/2015). The study is funded by the Lebanese University and Centre National de Recherche Scientifique, Lebanon (Number: 652 on 14/04/2016). Conclusion: This prospective controlled clinical trial will give information about the effect of RME on the glenoid fossa and condyle-fossa relationship and its impact on the nasal cavity width. Trial Registration: Retrospectively registered in BioMed Central (DOI10.1186/ISRCTN77788053). PMID:29780738

Lattice dynamics and thermomechanical properties of zirconium(IV) chloride: Evidence for low-temperature negative thermal expansion

NASA Astrophysics Data System (ADS)

Kim, Eunja; Weck, Philippe F.; Borjas, Rosendo; Poineau, Frederic

2018-01-01

The crystal structure, lattice dynamics and themomechanical properties of bulk monoclinic zirconium tetrachloride (ZrCl4) have been investigated using zero-damping dispersion-corrected density functional theory [DFT-D3(zero)]. Phonon analysis reveals that ZrCl4 (cr) undergoes negative thermal expansion (NTE) near T ≈ 10 K, with a coefficient of thermal expansion of α = - 1.2 ppm K-1 and a Grüneisen parameter of γ = - 1.1 . The bulk modulus is predicted to vary from K0 = 8.7 to 7.0 GPa in the temperature range 0-550 K. The isobaric molar heat capacity derived from phonon calculations within the quasi-harmonic approximation is in fair agreement with existing calorimetric data.

Anomalous expansion of Nb nanowires in a NiTi matrix under high pressure

DOE PAGES

Yu, Cun; Ren, Yang; Cui, Lishan; ...

2016-10-17

Under high pressure, materials usually shrink during compression as described by an equation of state. Here, we present the anomalous volume expansion behavior of a one-dimensional Nb nanowire embedded in a NiTi transforming matrix, while the matrix undergoes a pressure-induced martensitic transformation. The Nb volume expansion depends on the NiTi transition pressure range from the matrix, which is controlled by the shear strain induced by different pressure transmitting media. The transformation-induced interfacial stresses between Nb and NiTi may play a major role in this anomaly. In conclusion, our discovery sheds new light on the nano-interfacial effect on mechanical anomalies inmore » heterogeneous systems during a pressure-induced phase transition.« less

Dynamics of Robertson–Walker spacetimes with diffusion

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

Alho, A., E-mail: aalho@math.ist.utl.pt; Calogero, S., E-mail: calogero@chalmers.se; Machado Ramos, M.P., E-mail: mpr@mct.uminho.pt

2015-03-15

We study the dynamics of spatially homogeneous and isotropic spacetimes containing a fluid undergoing microscopic velocity diffusion in a cosmological scalar field. After deriving a few exact solutions of the equations, we continue by analyzing the qualitative behavior of general solutions. To this purpose we recast the equations in the form of a two dimensional dynamical system and perform a global analysis of the flow. Among the admissible behaviors, we find solutions that are asymptotically de-Sitter both in the past and future time directions and which undergo accelerated expansion at all times.

Langevin synchronization in a time-dependent, harmonic basin: An exact solution in 1D

NASA Astrophysics Data System (ADS)

Cadilhe, A.; Voter, Arthur F.

2018-02-01

The trajectories of two particles undergoing Langevin dynamics while sharing a common noise sequence can merge into a single (master) trajectory. Here, we present an exact solution for a particle undergoing Langevin dynamics in a harmonic, time-dependent potential, thus extending the idea of synchronization to nonequilibrium systems. We calculate the synchronization level, i.e., the mismatch between two trajectories sharing a common noise sequence, in the underdamped, critically damped, and overdamped regimes. Finally, we provide asymptotic expansions in various limiting cases and compare to the time independent case.

How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis.

PubMed

Xu, Min; He, Chunyang; Liu, Zhifeng; Dou, Yinyin

2016-01-01

Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth-infilling, edge expansion, and leapfrog-edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China.

How Did Urban Land Expand in China between 1992 and 2015? A Multi-Scale Landscape Analysis

PubMed Central

Xu, Min; He, Chunyang; Liu, Zhifeng; Dou, Yinyin

2016-01-01

Effective and timely quantification of the spatiotemporal pattern of urban expansion in China is important for the assessment of its environmental effects. However, the dynamics of the most recent urban expansions in China since 2012 have not yet been adequately explained due to a lack of current information. In this paper, our objective was to quantify spatiotemporal patterns of urban expansion in China between 1992 and 2015. First, we extracted information on urban expansion in China between 1992 and 2015 by integrating nighttime light data, vegetation index data, and land surface temperature data. Then we analyzed the spatiotemporal patterns of urban expansion at the national and regional scales, as well as at that of urban agglomerations. We found that China experienced a rapid and large-scale process of urban expansion between 1992 and 2015, with urban land increasing from 1.22 × 104 km2 to 7.29 × 104 km2, increasing in size nearly fivefold and with an average annual growth rate of 8.10%, almost 2.5 times as rapid as the global average. We also found that urban land in China expanded mainly by occupying 3.31 × 104 km2 of cropland, which comprised 54.67% of the total area of expanded urban land. Among the three modes of growth—infilling, edge expansion, and leapfrog—edge expansion was the main cause of cropland loss. Cropland loss resulting from edge expansion of urban land totalled 2.51 × 104 km2, accounting for over 75% of total cropland loss. We suggest that effective future management with respect to edge expansion of urban land is needed to protect cropland in China. PMID:27144589

Elasticity of the living abdominal wall in laparoscopic surgery.

PubMed

Song, Chengli; Alijani, Afshin; Frank, Tim; Hanna, George; Cuschieri, Alfred

2006-01-01

Laparoscopic surgery requires inflation of the abdominal cavity and this offers a unique opportunity to measure the mechanical properties of the living abdominal wall. We used a motion analysis system to study the abdominal wall motion of 18 patients undergoing laparoscopic surgery, and found that the mean Young's modulus was 27.7+/-4.5 and 21.0+/-3.7 kPa for male and female, respectively. During inflation, the abdominal wall changed from a cylinder to a dome shape. The average expansion in the abdominal wall surface was 20%, and a working space of 1.27 x 10(-3)m(3) was created by expansion, reshaping of the abdominal wall and diaphragmatic movement. For the first time, the elasticity of human abdominal wall was obtained from the patients undergoing laparoscopic surgery, and a 3D simulation model of human abdominal wall has been developed to analyse the motion pattern in laparoscopic surgery. Based on this study, a mechanical abdominal wall lift and a surgical simulator for safe/ergonomic port placements are under development.

Use of cyanoacrylate glue for temporary tarsorrhaphy in children.

PubMed

Trivedi, Dipti; McCalla, Maureen; Squires, Zoe; Parulekar, Manoj

2014-01-01

Congenital anophthalmia and postenucleation socket contracture are difficult conditions that require serial socket expansion with the use of hydrogel expanders and custom-made conformers along with temporary tarsorrhaphy. The authors undertook a part prospective case review of all children undergoing temporary tarsorrhaphy using cyanoacrylate glue over a 3-year period at a tertiary specialist children's hospital. They report a series of 7 children undergoing temporary tarsorrhaphy with cyanoacrylate glue instead of the conventional suturing technique. Indications were socket expansion (n = 4), fornix deepening (n = 2), prosthesis reposition, and prolapsed conjunctiva following enucleation (n = 1).The age range was 3 weeks to 14 years (mean, 2.7 years). The glue tarsorrhaphy lasted between 0.5 and 13 weeks (mean, 4.5 weeks). There were no adverse outcomes, and the glue tarsorrhaphy was tolerated well in all cases, with relative ease of reapplication of glue in clinic. Their study demonstrates that this technique allows quick and efficient temporary tarsorrhaphy with relative ease of reapplication in a clinic setting, avoiding the need for multiple general anesthetics.

Plasma Centrifuge Heat Engine - a Route to Non-thermal p- 11 B Fusion

NASA Astrophysics Data System (ADS)

Barnes, D. C.

2007-06-01

An invention [US Patent and Trademark Office App. Nos. 60/596567 (2005) and 60/766791 (2006)] combines centrifugal and dipole confinement, with recent oscillating plasma theory. The plasma undergoes compression/expansion (C/E), parallel to B by centrifugal force and perpendicular to B by B variation, providing a thermal cycle which recovers most (>95%) of heating as mechanical energy. This gives a "Q-amplifier" for beam-target systems. Centrifugally confined Boron plasma undergoes C/E by slow, cross-B interchange activity. Parallel and perpendicular C/E are matched by the rotation profile which arises naturally. Hot plasma is heated and cold plasma is cooled. Beam-target fusion reactions occur in the hot plasma region and expansion returns most of the heat energy as rotation energy. Rotation energy, in turn, produces waves which drive protons to an energy near the fusion peak cross section. A possible machine, including the arrangement of magnets and HV, is described.

Three-dimensional alterations in pharyngeal airway and maxillary sinus volumes in Class III maxillary deficiency subjects undergoing orthopedic facemask treatment.

PubMed

Pamporakis, Paschalis; Nevzatoğlu, Şirin; Küçükkeleş, Nazan

2014-07-01

To assess short-term alterations in the volume of pharyngeal airway space and maxillary sinuses associated with rapid maxillary expansion (RME) and facemask (FM) use in growing Class III maxillary-deficient patients. Twenty-two patients (14 girls, eight boys) treated with the RME/FM and having pretreatment and posttreatment cone beam-computed tomographic scans were identified from the archives of the Marmara University, Department of Orthodontics. According to the protraction force that was used, they were divided into two groups: a group with 400 g protraction force (12 subjects) and a group with 800 g protraction force (10 subjects). Mean age for the study group was 10 years. All patients were diagnosed with normal/low vertical growth pattern, maxillary deficiency, and normal mandible. No control group was available for this study. For each patient, a hyrax expansion screw with acrylic cap splint was constructed and RME was performed for 10 days. On the seventh day, protraction with a FM started. The results showed a statistically significant increase in the volume of maxillary sinuses after treatment, which was related to the growth. On the other hand, the increase in the volume of pharyngeal airway was not statistically significant. RME/FM treatment did not affect at all the volume of maxillary sinuses and actually inhibited the normal expected increase of the volume of the pharynx when compared with a control group comprising normal individuals.

Profilin-Dependent Nucleation and Assembly of Actin Filaments Controls Cell Elongation in Arabidopsis1[OPEN

PubMed Central

Cao, Lingyan; Blanchoin, Laurent; Staiger, Christopher J.

2016-01-01

Actin filaments in plant cells are incredibly dynamic; they undergo incessant remodeling and assembly or disassembly within seconds. These dynamic events are choreographed by a plethora of actin-binding proteins, but the exact mechanisms are poorly understood. Here, we dissect the contribution of Arabidopsis (Arabidopsis thaliana) PROFILIN1 (PRF1), a conserved actin monomer-binding protein, to actin organization and single filament dynamics during axial cell expansion of living epidermal cells. We found that reduced PRF1 levels enhanced cell and organ growth. Surprisingly, we observed that the overall frequency of nucleation events in prf1 mutants was dramatically decreased and that a subpopulation of actin filaments that assemble at high rates was reduced. To test whether profilin cooperates with plant formin proteins to execute actin nucleation and rapid filament elongation in cells, we used a pharmacological approach. Here, we used Small Molecule Inhibitor of Formin FH2 (SMIFH2), after validating its mode of action on a plant formin in vitro, and observed a reduced nucleation frequency of actin filaments in live cells. Treatment of wild-type epidermal cells with SMIFH2 mimicked the phenotype of prf1 mutants, and the nucleation frequency in prf1-2 mutant was completely insensitive to these treatments. Our data provide compelling evidence that PRF1 coordinates the stochastic dynamic properties of actin filaments by modulating formin-mediated actin nucleation and assembly during plant cell expansion. PMID:26574597

Petunia Phospholipase C1 Is Involved in Pollen Tube Growth[W

PubMed Central

Dowd, Peter E.; Coursol, Sylvie; Skirpan, Andrea L.; Kao, Teh-hui; Gilroy, Simon

2006-01-01

Although pollen tube growth is essential for plant fertilization and reproductive success, the regulators of the actin-related growth machinery and the cytosolic Ca2+ gradient thought to determine how these cells elongate remain poorly defined. Phospholipases, their substrates, and their phospholipid turnover products have been proposed as such regulators; however, the relevant phospholipase(s) have not been characterized. Therefore, we cloned cDNA for a pollen-expressed phosphatidylinositol 4,5-bisphosphate (PtdInsP2)–cleaving phospholipase C (PLC) from Petunia inflata, named Pet PLC1. Expressing a catalytically inactive form of Pet PLC1 in pollen tubes caused expansion of the apical Ca2+ gradient, disruption of the organization of the actin cytoskeleton, and delocalization of growth at the tube tip. These phenotypes were suppressed by depolymerizing actin with low concentrations of latrunculin B, suggesting that a critical site of action of Pet PLC1 is in regulating actin structure at the growing tip. A green fluorescent protein (GFP) fusion to Pet PLC1 caused enrichment in regions of the apical plasma membrane not undergoing rapid expansion, whereas a GFP fusion to the PtdInsP2 binding domain of mammalian PLC δ1 caused enrichment in apical regions depleted in PLC. Thus, Pet PLC1 appears to be involved in the machinery that restricts growth to the very apex of the elongating pollen tube, likely through its regulatory action on PtdInsP2 distribution within the cell. PMID:16648366

Dynamic thermal field-induced gradient soft-shear for highly oriented block copolymer thin films.

PubMed

Singh, Gurpreet; Yager, Kevin G; Berry, Brian; Kim, Ho-Cheol; Karim, Alamgir

2012-11-27

As demand for smaller, more powerful, and energy-efficient devices continues, conventional patterning technologies are pushing up against fundamental limits. Block copolymers (BCPs) are considered prime candidates for a potential solution via directed self-assembly of nanostructures. We introduce here a facile directed self-assembly method to rapidly fabricate unidirectionally aligned BCP nanopatterns at large scale, on rigid or flexible template-free substrates via a thermally induced dynamic gradient soft-shear field. A localized differential thermal expansion at the interface between a BCP film and a confining polydimethylsiloxane (PDMS) layer due to a dynamic thermal field imposes the gradient soft-shear field. PDMS undergoes directional expansion (along the annealing direction) in the heating zone and contracts back in the cooling zone, thus setting up a single cycle of oscillatory shear (maximum lateral shear stress ∼12 × 10(4) Pa) in the system. We successfully apply this process to create unidirectional alignment of BCP thin films over a wide range of thicknesses (nm to μm) and processing speeds (μm/s to mm/s) using both a flat and patterned PDMS layer. Grazing incidence small-angle X-ray scattering measurements show absolutely no sign of isotropic population and reveal ≥99% aligned orientational order with an angular spread Δθ(fwhm) ≤ 5° (full width at half-maximum). This method may pave the way to practical industrial use of hierarchically patterned BCP nanostructures.

Rapid Microfluidic Mixers Utilizing Dispersion Effect and Interactively Time-Pulsed Injection

NASA Astrophysics Data System (ADS)

Leong, Jik-Chang; Tsai, Chien-Hsiung; Chang, Chin-Lung; Lin, Chiu-Feng; Fu, Lung-Ming

2007-08-01

In this paper, we present a novel active microfluidic mixer utilizing a dispersion effect in an expansion chamber and applying interactively time-pulsed driving voltages to the respective inlet fluid flows to induce electroosmotic flow velocity variations for developing a rapid mixing effect in a microchannel. Without using any additional equipment to induce flow perturbations, only a single high-voltage power source is required for simultaneously driving and mixing sample fluids, which results in a simple and low-cost system for mixing. The effects of the applied main electrical field, interactive frequency, and expansion ratio on the mixing performance are thoroughly examined experimentally and numerically. The mixing ratio can be as high as 95% within a mixing length of 3000 μm downstream from the secondary T-form when a driving electric field strength of 250 V/cm, a periodic switching frequency of 5 Hz, and the expansion ratio M=1:10 are applied. In addition, the optimization of the driving electric field, switching frequency, expansion ratio, expansion entry length, and expansion chamber length for achieving a maximum mixing ratio is also discussed in this study. The novel method proposed in this study can be used for solving the mixing problem in the field of micro-total-analysis systems in a simple manner.

Soil physical quality response to sugarcane expansion in Brazil

USDA-ARS?s Scientific Manuscript database

With an increasing global demand for bioenergy, the rate of land-use change (LUC) is increasing rapidly to support cellulosic feedstock production. In Brazil, sugarcane (Saccharum officinarum) expansion to produce ethanol is displacing degraded pastures, but long-term effects of this LUC are unknown...

Scaling behavior of ground-state energy cluster expansion for linear polyenes

NASA Astrophysics Data System (ADS)

Griffin, L. L.; Wu, Jian; Klein, D. J.; Schmalz, T. G.; Bytautas, L.

Ground-state energies for linear-chain polyenes are additively expanded in a sequence of terms for chemically relevant conjugated substructures of increasing size. The asymptotic behavior of the large-substructure limit (i.e., high-polymer limit) is investigated as a means of characterizing the rapidity of convergence and consequent utility of this energy cluster expansion. Consideration is directed to computations via: simple Hückel theory, a refined Hückel scheme with geometry optimization, restricted Hartree-Fock self-consistent field (RHF-SCF) solutions of fixed bond-length Parisier-Parr-Pople (PPP)/Hubbard models, and ab initio SCF approaches with and without geometry optimization. The cluster expansion in what might be described as the more "refined" approaches appears to lead to qualitatively more rapid convergence: exponentially fast as opposed to an inverse power at the simple Hückel or SCF-Hubbard levels. The substructural energy cluster expansion then seems to merit special attention. Its possible utility in making accurate extrapolations from finite systems to extended polymers is noted.

Nuclear Reaction Rates and the Production of Light P-Process Isotopes in Fast Expansions of Proton-Rich Matter

NASA Astrophysics Data System (ADS)

Jordan, G. C., IV; Meyer, B. S.

2004-09-01

We study nucleosynthesis in rapid expansions of proton-rich matter such as might occur in winds from newly-born neutron stars. For rapid enough expansion, the system fails to maintain an equilibrium between neutrons and protons and the abundant 4He nuclei. This leads to production of quite heavy nuclei early in the expansion. As the temperature falls, the system attempts to re-establish the equilibrium between free nucleons and 4He. This causes the abundance of free neutrons to drop and the heavy nuclei to disintegrate. If the disintegration flows quench before the nuclei reach the iron group, a distribution of p-process nuclei remains. We briefly discuss the possibility of this process as the mechanism of production of light p-process isotopes (specifically 92Mo, 94Mo, 96Ru, and 98Ru), and we provide a qualitative assessment of the impact of nuclear reaction rates of heavy, proton rich isotopes on the production of these astrophysically important nuclides.

COBRA encodes a putative GPI-anchored protein, which is polarly localized and necessary for oriented cell expansion in Arabidopsis.

PubMed

Schindelman, G; Morikami, A; Jung, J; Baskin, T I; Carpita, N C; Derbyshire, P; McCann, M C; Benfey, P N

2001-05-01

To control organ shape, plant cells expand differentially. The organization of the cellulose microfibrils in the cell wall is a key determinant of differential expansion. Mutations in the COBRA (COB) gene of Arabidopsis, known to affect the orientation of cell expansion in the root, are reported here to reduce the amount of crystalline cellulose in cell walls in the root growth zone. The COB gene, identified by map-based cloning, contains a sequence motif found in proteins that are anchored to the extracellular surface of the plasma membrane through a glycosylphosphatidylinositol (GPI) linkage. In animal cells, this lipid linkage is known to confer polar localization to proteins. The COB protein was detected predominately on the longitudinal sides of root cells in the zone of rapid elongation. Moreover, COB RNA levels are dramatically upregulated in cells entering the zone of rapid elongation. Based on these results, models are proposed for the role of COB as a regulator of oriented cell expansion.

COBRA encodes a putative GPI-anchored protein, which is polarly localized and necessary for oriented cell expansion in Arabidopsis

PubMed Central

Schindelman, Gary; Morikami, Atsushi; Jung, Jee; Baskin, Tobias I.; Carpita, Nicholas C.; Derbyshire, Paul; McCann, Maureen C.; Benfey, Philip N.

2001-01-01

To control organ shape, plant cells expand differentially. The organization of the cellulose microfibrils in the cell wall is a key determinant of differential expansion. Mutations in the COBRA (COB) gene of Arabidopsis, known to affect the orientation of cell expansion in the root, are reported here to reduce the amount of crystalline cellulose in cell walls in the root growth zone. The COB gene, identified by map-based cloning, contains a sequence motif found in proteins that are anchored to the extracellular surface of the plasma membrane through a glycosylphosphatidylinositol (GPI) linkage. In animal cells, this lipid linkage is known to confer polar localization to proteins. The COB protein was detected predominately on the longitudinal sides of root cells in the zone of rapid elongation. Moreover, COB RNA levels are dramatically upregulated in cells entering the zone of rapid elongation. Based on these results, models are proposed for the role of COB as a regulator of oriented cell expansion. PMID:11331607

A two-parameter family of double-power-law biorthonormal potential-density expansions

NASA Astrophysics Data System (ADS)

Lilley, Edward J.; Sanders, Jason L.; Evans, N. Wyn

2018-07-01

We present a two-parameter family of biorthonormal double-power-law potential-density expansions. Both the potential and density are given in a closed analytic form and may be rapidly computed via recurrence relations. We show that this family encompasses all the known analytic biorthonormal expansions: the Zhao expansions (themselves generalizations of ones found earlier by Hernquist & Ostriker and by Clutton-Brock) and the recently discovered Lilley et al. expansion. Our new two-parameter family includes expansions based around many familiar spherical density profiles as zeroth-order models, including the γ models and the Jaffe model. It also contains a basis expansion that reproduces the famous Navarro-Frenk-White (NFW) profile at zeroth order. The new basis expansions have been found via a systematic methodology which has wide applications in finding other new expansions. In the process, we also uncovered a novel integral transform solution to Poisson's equation.

A two-parameter family of double-power-law biorthonormal potential-density expansions

NASA Astrophysics Data System (ADS)

Lilley, Edward J.; Sanders, Jason L.; Evans, N. Wyn

2018-05-01

We present a two-parameter family of biorthonormal double-power-law potential-density expansions. Both the potential and density are given in closed analytic form and may be rapidly computed via recurrence relations. We show that this family encompasses all the known analytic biorthonormal expansions: the Zhao expansions (themselves generalizations of ones found earlier by Hernquist & Ostriker and by Clutton-Brock) and the recently discovered Lilley et al. (2017a) expansion. Our new two-parameter family includes expansions based around many familiar spherical density profiles as zeroth-order models, including the γ models and the Jaffe model. It also contains a basis expansion that reproduces the famous Navarro-Frenk-White (NFW) profile at zeroth order. The new basis expansions have been found via a systematic methodology which has wide applications in finding other new expansions. In the process, we also uncovered a novel integral transform solution to Poisson's equation.

A two-parameter family of double-power-law biorthonormal potential-density expansions

NASA Astrophysics Data System (ADS)

Lilley, Edward J.; Sanders, Jason L.; Evans, N. Wyn

2018-05-01

We present a two-parameter family of biorthonormal double-power-law potential-density expansions. Both the potential and density are given in closed analytic form and may be rapidly computed via recurrence relations. We show that this family encompasses all the known analytic biorthonormal expansions: the Zhao expansions (themselves generalizations of ones found earlier by Hernquist & Ostriker and by Clutton-Brock) and the recently discovered Lilley et al. (2018b) expansion. Our new two-parameter family includes expansions based around many familiar spherical density profiles as zeroth-order models, including the γ models and the Jaffe model. It also contains a basis expansion that reproduces the famous Navarro-Frenk-White (NFW) profile at zeroth order. The new basis expansions have been found via a systematic methodology which has wide applications in finding other new expansions. In the process, we also uncovered a novel integral transform solution to Poisson's equation.

Physiological and behavioral responses of poultry exposed to gas-filled high expansion foam.

PubMed

McKeegan, D E F; Reimert, H G M; Hindle, V A; Boulcott, P; Sparrey, J M; Wathes, C M; Demmers, T G M; Gerritzen, M A

2013-05-01

Disease control measures require poultry to be killed on farms to minimize the risk of disease being transmitted to other poultry and, in some cases, to protect public health. We assessed the welfare implications for poultry of the use of high-expansion gas-filled foam as a potentially humane, emergency killing method. In laboratory trials, broiler chickens, adult laying hens, ducks, and turkeys were exposed to air-, N2-, or CO2-filled high expansion foam (expansion ratio 300:1) under standardized conditions. Birds were equipped with sensors to measure cardiac and brain activity, and measurements of oxygen concentration in the foam were carried out. Initial behavioral responses to foam were not pronounced but included headshakes and brief bouts of wing flapping. Both N2- and CO2-filled foam rapidly induced ataxia/loss of posture and vigorous wing flapping in all species, characteristic of anoxic death. Immersion in air-filled, high expansion foam had little effect on physiology or behavior. Physiological responses to both N2- and CO2-filled foam were characterized by a pronounced bradyarrythymia and a series of consistent changes in the appearance of the electroencephalogram. These were used to determine an unequivocal time to loss of consciousness in relation to submersion. Mean time to loss of consciousness was 30 s in hens and 18 s in broilers exposed to N2-filled foam, and 16 s in broilers, 1 s in ducks, and 15 s in turkeys exposed to CO2-filled foam. Euthanasia achieved with anoxic foam was particularly rapid, which is explained by the very low oxygen concentrations (below 1%) inside the foam. Physiological observations and postmortem examination showed that the mode of action of high expansion, gas-filled foam is anoxia, not occlusion of the airway. These trials provide proof-of-principle that submersion in gas-filled, high expansion foam provides a rapid and highly effective method of euthanasia, which may have potential to provide humane emergency killing or routine depopulation.

Quality in health care and globalization of health services: accreditation and regulatory oversight of medical tourism companies.

PubMed

Turner, Leigh G

2011-02-01

Patients are crossing national borders in search of affordable and timely health care. Many medical tourism companies are now involved in organizing cross-border health services. Despite the rapid expansion of the medical tourism industry, few standards exist to ensure that these businesses organize high-quality, competent international health care. Addressing the regulatory vacuum, 10 standards are proposed as a framework for regulating the medical tourism industry. Medical tourism companies should have to undergo accreditation review. Care should be arranged only at accredited international health-care facilities. Standards should be established to ensure that clients of medical tourism companies make informed choices. Continuity of care needs to become an integral feature of cross-border care. Restrictions should be placed on the use of waiver of liability forms by medical tourism companies. Medical tourism companies must ensure that they conform to relevant legislation governing privacy and confidentiality of patient information. Restrictions must be placed on the types of health services marketed by medical tourism companies. Representatives of medical tourism agencies should have to undergo training and certification. Medical travel insurance and medical complications insurance should be included in the health-care plans of patients traveling for care. To protect clients from financial losses, medical tourism companies should be mandated to contribute to compensation funds. Establishing high standards for the operation of medical tourism companies should reduce risks facing patients when they travel abroad for health care.

Gradients in Wall Mechanics and Polysaccharides along Growing Inflorescence Stems.

PubMed

Phyo, Pyae; Wang, Tuo; Kiemle, Sarah N; O'Neill, Hugh; Pingali, Sai Venkatesh; Hong, Mei; Cosgrove, Daniel J

2017-12-01

At early stages of Arabidopsis ( Arabidopsis thaliana ) flowering, the inflorescence stem undergoes rapid growth, with elongation occurring predominantly in the apical ∼4 cm of the stem. We measured the spatial gradients for elongation rate, osmotic pressure, cell wall thickness, and wall mechanical compliances and coupled these macroscopic measurements with molecular-level characterization of the polysaccharide composition, mobility, hydration, and intermolecular interactions of the inflorescence cell wall using solid-state nuclear magnetic resonance spectroscopy and small-angle neutron scattering. Force-extension curves revealed a gradient, from high to low, in the plastic and elastic compliances of cell walls along the elongation zone, but plots of growth rate versus wall compliances were strikingly nonlinear. Neutron-scattering curves showed only subtle changes in wall structure, including a slight increase in cellulose microfibril alignment along the growing stem. In contrast, solid-state nuclear magnetic resonance spectra showed substantial decreases in pectin amount, esterification, branching, hydration, and mobility in an apical-to-basal pattern, while the cellulose content increased modestly. These results suggest that pectin structural changes are connected with increases in pectin-cellulose interaction and reductions in wall compliances along the apical-to-basal gradient in growth rate. These pectin structural changes may lessen the ability of the cell wall to undergo stress relaxation and irreversible expansion (e.g. induced by expansins), thus contributing to the growth kinematics of the growing stem. © 2017 American Society of Plant Biologists. All Rights Reserved.

[With the things on the back: estate remodelling and inter-urban mobility].

PubMed

Cela, J

1992-01-01

This work argues that intraurban mobility resulting from urban renewal in Santo Domingo is one of the city's major problems. Santo Domingo's growth from 30,000 in 1920 to 1,800,000 in the late 1980s was unplanned, and the expansion of urban infrastructure generally followed demographic expansion. The Dominican government has regularly provoked massive dislocations in the course of urban renewal, especially at the end of the Trujillo era and under the governments of Balaguer. More than 50,000 families have been forced to move in the past 30 years, representing 20% of the population. Among the consequences of this policy are a form of rootlessness of the population resulting from lack of title to the land and the constant threat of having to move again. The feeling of impermanence has psychological and cultural effects and also discourages residents from making significant improvements to their housing. The disorder of the city is increased because most of the families forced to move from areas undergoing renewal establish themselves in other marginal zones, which then undergo chaotic growth. From the fall of Trujillo to the disturbances of 1965-66, rural migration to the periphery of the city was massive, and it resumed again with the return of political stability. The massive construction projects beginning in 1967 were intended to beautify areas of high visibility, improve traffic flow, develop aesthetic elements, and remove low income populations from the center for the city. Around one-third of the national budget was devoted to construction in these years. Thousands of families were relocated in new areas belonging to the government at great distances from the city center and with few or no public services. The urban policy encouraged speculation and deterioration of urban management due to confusion between government institutions and private interests. Between 1978-86, government construction policy changed, with the amount of investment reduced and low cost housing emphasized. But massive construction began again with Balaguer's return to power. Some 20,000 families have been displaced and another 14,000 have been told to move. The forced removals have involved around 10% of the population. Their effects have included rapid expansion of the marginal urban periphery, artificially high rents, aggravation of problems in providing public services, loss of identity of neighborhoods, reinforcement of individual strategies at the expense of communal welfare, and weakening of survival resources of the most impoverished sectors.

Rapid three-dimensional microfluidic mixer for high viscosity solutions to unravel earlier folding kinetics of G-quadruplex under molecular crowding conditions.

PubMed

Liu, Chao; Li, Ying; Li, Yiwei; Chen, Peng; Feng, Xiaojun; Du, Wei; Liu, Bi-Feng

2016-01-01

Rapid mixing of highly viscous solutions is a great challenge, which helps to analyze the reaction kinetics in viscous liquid phase, particularly to discover the folding kinetics of macromolecules under molecular crowding conditions mimicking the conditions inside cells. Here, we demonstrated a novel microfluidic mixer based on Dean flows with three-dimensional (3D) microchannel configuration for fast mixing of high-viscosity fluids. The main structure contained three consecutive subunits, each consisting of a "U"-type channel followed by a chamber with different width and height. Thus, the two solutions injected from the two inlets would undergo a mixing in the first "U"-type channel due to the Dean flow effect, and simultaneous vortices expansions in both horizontal and vertical directions in the following chamber. Numerical simulations and experimental characterizations confirmed that the micromixer could achieve a mixing time of 122.4μs for solutions with viscosities about 33.6 times that of pure water. It was the fastest micromixer for high viscosity solutions compared with previous reports. With this highly efficient 3D microfluidic mixer, we further characterized the early folding kinetics of human telomere G-quadruplex under molecular crowding conditions, and unravelled a new folding process within 550μs. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of orthopedic maxillary expansion on nasal cavity size in growing subjects: a low dose computer tomography clinical trial.

PubMed

Cordasco, Giancarlo; Nucera, Riccardo; Fastuca, Rosamaria; Matarese, Giovanni; Lindauer, Steven J; Leone, Pietro; Manzo, Paolo; Martina, Roberto

2012-11-01

The aim of this retrospective clinical trial was to evaluate the effects of rapid maxillary expansion on skeletal nasal cavity size in growing subjects by use of low dose computer tomography. Eight Caucasian children (three male; five female) with a mean age of 9.7 years (SD±1.41) were the final sample of this research that underwent palatal expansion as a first phase of orthodontic treatment. The maxillary expander was banded to the upper first molars and was activated according a rapid maxillary expansion protocol. Low-dose computer tomography examinations of maxilla and of the low portion of nasal cavity were performed before inserting the maxillary expander (T0) and at the end of retention (T1), 7 months later. A low-dose computer tomography protocol was applied during the exams. Image processing was achieved in 3 steps: reslicing; dental and skeletal measurements; skeletal nasal volume computing. A set of reproducible skeletal and dental landmarks were located in the coronal passing through the first upper right molar furcation. Using the landmarks, a set of transverse linear measurements were identified to estimate maximum nasal width and nasal floor width. To compute the nasal volume the lower portion of the nasal cavity was set as region of interest. Nasal volume was calculated using a set of coronal slices. In each coronal slice, the cortical bone of the nasal cavity was identified and selected with a segmentation technique. Dependent t-tests were used to evaluate changes due to expansion. For all tests, a significance level of P<0.05 was used. Rapid maxillary expansion produced significant increases of linear transverse skeletal measurements, these increments were bigger in the lower portion of the nasal cavities: nasal floor width (+3.15 mm; SD ± 0.99), maximum nasal width (+2.47 mm; SD ± 0.99). Rapid maxillary expansion produced significant increment of the total nasal volume (+1.27 cm(3) ± SD 0.65). The anterior volume increase was 0.58 cm(3) while the posterior one was 0.69 cm(3). In growing subjects RME is able to significantly enlarge the dimension of nasal cavity. The increment is bigger in the lower part of the nose and equally distributed between the anterior e the posterior part of the nasal cavity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Prediction and Observation of Post-Admission Hematoma Expansion in Patients with Intracerebral Hemorrhage

PubMed Central

Ovesen, Christian; Havsteen, Inger; Rosenbaum, Sverre; Christensen, Hanne

2014-01-01

Post-admission hematoma expansion in patients with intracerebral hemorrhage (ICH) comprises a simultaneous major clinical problem and a possible target for medical intervention. In any case, the ability to predict and observe hematoma expansion is of great clinical importance. We review radiological concepts in predicting and observing post-admission hematoma expansion. Hematoma expansion can be observed within the first 24 h after symptom onset, but predominantly occurs in the early hours. Thus capturing markers of on-going bleeding on imaging techniques could predict hematoma expansion. The spot sign observed on computed tomography angiography is believed to represent on-going bleeding and is to date the most well investigated and reliable radiological predictor of hematoma expansion as well as functional outcome and mortality. On non-contrast CT, the presence of foci of hypoattenuation within the hematoma along with the hematoma-size is reported to be predictive of hematoma expansion and outcome. Because patients tend to arrive earlier to the hospital, a larger fraction of acute ICH-patients must be expected to undergo hematoma expansion. This renders observation and radiological follow-up investigations increasingly relevant. Transcranial duplex sonography has in recent years proven to be able to estimate hematoma volume with good precision and could be a valuable tool in bedside serial observation of acute ICH-patients. Future studies will elucidate, if better prediction and observation of post-admission hematoma expansion can help select patients, who will benefit from hemostatic treatment. PMID:25324825

Effect of the laser and light-emitting diode (LED) phototherapy on midpalatal suture bone formation after rapid maxilla expansion: a Raman spectroscopy analysis.

PubMed

Rosa, Cristiane Becher; Habib, Fernando Antonio Lima; de Araújo, Telma Martins; Aragão, Juliana Silveira; Gomes, Rafael Soares; Barbosa, Artur Felipe Santos; Silveira, Landulfo; Pinheiro, Antonio L B

2014-05-01

The aim of this study was to analyze the effect of laser or light-emitting diode (LED) phototherapy on the bone formation at the midpalatal suture after rapid maxilla expansion. Twenty young adult male rats were divided into four groups with 8 days of experimental time: group 1, no treatment; group 2, expansion; group 3, expansion and laser irradiation; and group 4, expansion and LED irradiation. In groups 3 and 4, light irradiation was in the first, third, and fifth experimental days. In all groups, the expansion was accomplished with a helicoid 0.020" stainless steel orthodontic spring. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm(2), t = 257 s, spatial average energy fluence (SAEF) of 18 J/cm(2)) or a LED (λ850 nm, 150 mW ± 10 mW, spot of 0.5 cm(2), t = 120 s, SAEF of 18 J/cm(2)) were used. The samples were analyzed by Raman spectroscopy carried out at midpalatal suture and at the cortical area close to the suture. Two Raman shifts were analyzed: ∼ 960 (phosphate hydroxyapatite) and ∼ 1,450 cm(-1) (lipids and protein). Data was submitted to statistical analysis. Significant statistical difference (p ≤ 0.05) was found in the hydroxyapatite (CHA) peaks among the expansion group and the expansion and laser or LED groups. The LED group presented higher mean peak values of CHA. No statistical differences were found between the treated groups as for collagen deposition, although LED also presented higher mean peak values. The results of this study using Raman spectral analysis indicate that laser and LED light irradiation improves deposition of CHA in the midpalatal suture after orthopedic expansion.

76 FR 76736 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-08

... Project Survey of Rapid Influenza Diagnostic Test (RIDT) Practices in Laboratories-NEW--the Office of...). Background and Brief Description The Survey of Rapid Influenza Diagnostic Testing Practices in Laboratories is a national systematic study investigating rapid influenza diagnostic testing practices in clinical...

Evaluation of the rapid and slow maxillary expansion using cone-beam computed tomography: a randomized clinical trial

PubMed Central

Pereira, Juliana da S.; Jacob, Helder B.; Locks, Arno; Brunetto, Mauricio; Ribeiro, Gerson L. U.

2017-01-01

ABSTRACT OBJECTIVE: The aim of this randomized clinical trial was to evaluate the dental, dentoalveolar, and skeletal changes occurring right after the rapid maxillary expansion (RME) and slow maxillary expansion (SME) treatment using Haas-type expander. METHODS: All subjects performed cone-beam computed tomography (CBCT) before installation of expanders (T1) and right after screw stabilization (T2). Patients who did not follow the research parameters were excluded. The final sample resulted in 21 patients in RME group (mean age of 8.43 years) and 16 patients in SME group (mean age of 8.70 years). Based on the skewness and kurtosis statistics, the variables were judged to be normally distributed and paired t-test and student t-test were performed at significance level of 5%. RESULTS: Intermolar angle changed significantly due to treatment and RME showed greater buccal tipping than SME. RME showed significant changes in other four measurements due to treatment: maxilla moved forward and mandible showed backward rotation and, at transversal level both skeletal and dentoalveolar showed significant changes due to maxillary expansion. SME showed significant dentoalveolar changes due to maxillary expansion. CONCLUSIONS: Only intermolar angle showed significant difference between the two modalities of maxillary expansion with greater buccal tipping for RME. Also, RME produced skeletal maxillary expansion and SME did not. Both maxillary expansion modalities were efficient to promote transversal gain at dentoalveolar level. Sagittal and vertical measurements did not show differences between groups, but RME promoted a forward movement of the maxilla and backward rotation of the mandible. PMID:28658357

Range expansion promotes cooperation in an experimental microbial metapopulation

PubMed Central

Datta, Manoshi Sen; Korolev, Kirill S.; Cvijovic, Ivana; Dudley, Carmel; Gore, Jeff

2013-01-01

Natural populations throughout the tree of life undergo range expansions in response to changes in the environment. Recent theoretical work suggests that range expansions can have a strong effect on evolution, even leading to the fixation of deleterious alleles that would normally be outcompeted in the absence of migration. However, little is known about how range expansions might influence alleles under frequency- or density-dependent selection. Moreover, there is very little experimental evidence to complement existing theory, since expanding populations are difficult to study in the natural environment. In this study, we have used a yeast experimental system to explore the effect of range expansions on the maintenance of cooperative behaviors, which commonly display frequency- and density-dependent selection and are widespread in nature. We found that range expansions favor the maintenance of cooperation in two ways: (i) through the enrichment of cooperators at the front of the expanding population and (ii) by allowing cooperators to “outrun” an invading wave of defectors. In this system, cooperation is enhanced through the coupling of population ecology and evolutionary dynamics in expanding populations, thus providing experimental evidence for a unique mechanism through which cooperative behaviors could be maintained in nature. PMID:23569263

A comparative study of tissue expansion and free parascapular flaps in extensive facial burn scar reconstruction

PubMed Central

Kalra, G S; Bedi, Mitesh; Barala, Vipin Kumar

2017-01-01

Background: Large post burn scars are a very difficult problem to treat. Available methods include skin grafts and tissue expansion. The reconstructive method used should be tailored according to individual patient rather than following a textbook approach in each. Patients and Methods: A retrospective analysis was done of cases with extensive facial burn scars in whom secondary reconstruction was done with either free parascapular flap cover or tissue expansion and flap advancement following facial burn scar excision by a single surgeon (GSK) in Department of Burns, Plastic and reconstructive surgery. Results: A total of 15 patients with free parascapular flap and 15 patients with tissue expansion followed by flap advancement were analyzed in the group. There were no free flap failures, but 2 patients required skin graft at donor site. In patients undergoing tissue expansion, minor complication was noted in 1 patient. Conclusion: Tissue expansion is a useful technique in reconstruction of post burn scars, but has its limitations, especially in patients with extensive burns in head and neck region with limited local tissue availability. Parascapular free flap may provide a good alternative option for reconstruction in such cases. PMID:28804686

Lattice dynamics and thermomechanical properties of zirconium(IV) chloride: Evidence for low-temperature negative thermal expansion

DOE PAGES

Kim, Eunja; Weck, Philippe F.; Borjas, Rosendo; ...

2017-11-01

For this research, the crystal structure, lattice dynamics and themomechanical properties of bulk monoclinic zirconium tetrachloride (ZrCl 4) have been investigated using zero-damping dispersion-corrected density functional theory [DFT-D3(zero)]. Phonon analysis reveals that ZrCl 4(cr) undergoes negative thermal expansion (NTE) near T≈10 K, with a coefficient of thermal expansion of α=-1.2 ppm K -1 and a Grüneisen parameter of γ=-1.1. The bulk modulus is predicted to vary from K 0=8.7 to 7.0 GPa in the temperature range 0–550 K. Lastly, the isobaric molar heat capacity derived from phonon calculations within the quasi-harmonic approximation is in fair agreement with existing calorimetric data.

Lattice dynamics and thermomechanical properties of zirconium(IV) chloride: Evidence for low-temperature negative thermal expansion

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

Kim, Eunja; Weck, Philippe F.; Borjas, Rosendo

For this research, the crystal structure, lattice dynamics and themomechanical properties of bulk monoclinic zirconium tetrachloride (ZrCl 4) have been investigated using zero-damping dispersion-corrected density functional theory [DFT-D3(zero)]. Phonon analysis reveals that ZrCl 4(cr) undergoes negative thermal expansion (NTE) near T≈10 K, with a coefficient of thermal expansion of α=-1.2 ppm K -1 and a Grüneisen parameter of γ=-1.1. The bulk modulus is predicted to vary from K 0=8.7 to 7.0 GPa in the temperature range 0–550 K. Lastly, the isobaric molar heat capacity derived from phonon calculations within the quasi-harmonic approximation is in fair agreement with existing calorimetric data.

Blastocoele expansion degree predicts live birth after single blastocyst transfer for fresh and vitrified/warmed single blastocyst transfer cycles.

PubMed

Du, Qing-Yun; Wang, En-Yin; Huang, Yan; Guo, Xiao-Yi; Xiong, Yu-Jing; Yu, Yi-Ping; Yao, Gui-Dong; Shi, Sen-Lin; Sun, Ying-Pu

2016-04-01

To evaluate the independent effects of the degree of blastocoele expansion and re-expansion and the inner cell mass (ICM) and trophectoderm (TE) grades on predicting live birth after fresh and vitrified/warmed single blastocyst transfer. Retrospective study. Reproductive medical center. Women undergoing 844 fresh and 370 vitrified/warmed single blastocyst transfer cycles. None. Live-birth rate correlated with blastocyst morphology parameters by logistic regression analysis and Spearman correlations analysis. The degree of blastocoele expansion and re-expansion was the only blastocyst morphology parameter that exhibited a significant ability to predict live birth in both fresh and vitrified/warmed single blastocyst transfer cycles respectively by multivariate logistic regression and Spearman correlations analysis. Although the ICM grade was significantly related to live birth in fresh cycles according to the univariate model, its effect was not maintained in the multivariate logistic analysis. In vitrified/warmed cycles, neither ICM nor TE grade was correlated with live birth by logistic regression analysis. This study is the first to confirm that the degree of blastocoele expansion and re-expansion is a better predictor of live birth after both fresh and vitrified/warmed single blastocyst transfer cycles than ICM or TE grade. Copyright © 2016. Published by Elsevier Inc.

Pathways of Barotrauma in Juvenile Salmonids Exposed to Simulated Hydroturbine Passage: Boyle’s Law vs. Henry’s Law

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

Brown, Richard S.; Pflugrath, Brett D.; Colotelo, Alison HA

2012-06-01

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing by the turbine blade may experience rapid decompression, the severity of which can be highly variable and may result in a number of barotraumas. The mechanisms of these injuries can be due to expansion of existing bubbles or gases coming out of solution; governed by Boyle’s Law and Henry’s Law, respectively. This paper combines re-analysis of published data with new experiments to gain a better understanding of the mechanisms of injury and mortality for fish experiencing rapid decompression associated with hydroturbine passage. From these data it appears thatmore » the majority of decompression related injuries are due to the expansion of existing bubbles in the fish, particularly the expansion and rupture of the swim bladder. This information is particularly useful for fisheries managers and turbine manufacturers, demonstrating that reducing the rate of swim bladder ruptures by reducing the frequency of occurrence and severity of rapid decompression during hydroturbine passage could reduce the rates of injury and mortality for hydroturbine passed juvenile salmonids.« less

State of the States in Developmental Disabilities: 2004

ERIC Educational Resources Information Center

Braddock, David; Hemp, Richard; Rizzolo, Mary C.

2004-01-01

Public spending for MR/DD services grew rapidly during FYs 2000-2002. This rapid growth was followed by reductions in spending for MR/DD services as the nation's economy declined during 2002-2004. However, convergent factors stimulating future expansion of funding and services for persons with MR/DD include rapidly expanding cohorts of aging…

Lamarck Will Not Lie Down.

ERIC Educational Resources Information Center

Lewin, Roger

1981-01-01

Describes recent research by Edward Steele appearing to support the Lamarckian theory of inheritance. Steele suggests that a mutant somatic cell favored by the environment will undergo clonal expansion. Altered genetic materials from these cells is then picked up by C-type viruses and inserted into the germ line genome. (CS)

Peruvian Higher Education: Expansions Amid Economic Crisis.

ERIC Educational Resources Information Center

Post, David

1991-01-01

Development of the Peruvian university system is described, focusing on periods of rapid expansion. Enrollment declines in 1974-78 are analyzed in the context of the educational reform program of the military government. The 1983 new university law, following return to civilian government, and future prospects for higher education are discussed.…

Rapid expansion of T cells: Effects of culture and cryopreservation and importance of short-term cell recovery.

PubMed

Sadeghi, Arian; Ullenhag, Gustav; Wagenius, Gunnar; Tötterman, Thomas H; Eriksson, Fredrik

2013-06-01

Successful cell therapy relies on the identification and mass expansion of functional cells for infusion. Cryopreservation of cells is an inevitable step in most cell therapies which also entails consequences for the frozen cells. This study assessed the impact of cryopreservation and the widely used protocol for rapid expansion of T lymphocytes. The effects on cell viability, immunocompetence and the impact on apoptotic and immunosuppressive marker expression were analyzed using validated assays. Cryopreservation of lymphocytes during the rapid expansion protocol did not affect cell viability. Lymphocytes that underwent mass expansion or culture in high dose IL-2 were unable to respond to PHA stimulation by intracellular ATP production immediately after thawing (ATP = 16 ± 11 ng/ml). However, their reactivity to PHA was regained within 48 hours of recovery (ATP = 356 ± 61 ng/ml). Analysis of mRNA levels revealed downregulation of TGF-β and IL-10 at all time points. Culture in high dose IL-2 led to upregulation of p73 and BCL-2 mRNA levels while FoxP3 expression was elevated after culture in IL-2 and artificial TCR stimuli. FoxP3 levels decreased after short-term recovery without IL-2 or stimulation. Antigen specificity, as determined by IFNγ secretion, was unaffected by cryopreservation but was completely lost after addition of high dose IL-2 and artificial TCR stimuli. In conclusion, allowing short-time recovery of mass expanded and cryopreserved cells before reinfusion could enhance the outcome of adoptive cell therapy as the cells regain immune competence and specificity.

Three-dimensional evaluation of upper airway following rapid maxillary expansion: a CBCT study.

PubMed

El, Hakan; Palomo, Juan Martin

2014-03-01

To evaluate, by using cone beam computed tomography, the skeletal, dental, oropharyngeal (OP) airway volume, and nasal passage (NP) volume changes that occur after rapid maxillary expansion (RME). Two groups were selected, each with 35 patients (15 males, 20 females), an RME group (mean age, 14.02 ± 1.46 years) and a control group (mean age, 14.10 ± 1.44 years). The RME group consisted of patients with maxillary constriction who were treated with Hyrax palatal expanders, and the control group comprised age- and sex-matched patients who underwent comprehensive orthodontic treatment without the use of a rapid maxillary expander. All of the transverse skeletal (medial orbital width, lateral nasal width, maxillary width, and mandibular width) and interdental (intermolar, interpremolar, and intercanine) parameters were significantly enlarged in the RME group. A statistically significant increase in airway variables was seen in both groups between pretreatment (T0) and final records (T1). The mean increase of NP airway volume for the RME group (1719.9 ± 1510.7 mm(3)) was twofold compared with the control group (813.6 ± 1006.7 mm(3)), and no intergroup significant difference was found for the OP volume. Rapid maxillary expansion creates a significant increase in nasal passage airway volume but no significant change in the oropharyngeal airway volume.

Novel micronisation β-carotene using rapid expansion supercritical solution with co-solvent

NASA Astrophysics Data System (ADS)

Kien, Le Anh

2017-09-01

Rapid expansion of supercritical solution (RESS) is the most common approach of pharmaceutical pacticle forming methods using supercritical fluids. The RESS method is a technology producing a small solid product with a very narrow particle size distribution, organic solvent-free particles. This process is also simple and easy to control the operating parameters in comparision with other ways based on supercritical techniques. In this study, β-carotene, a strongly colored red-orange pigment abundant in plants and fruits, has been forming by RESS. In addition, the size and morphology effect of four different RESS parameters including co-solvent, extraction temperature, and extraction pressure and expansion nozzle temperature has surveyed. The particle size distribution has been determined by using laser diffraction experiment. SEM has conducted to analyze the surface structure, DSC and FTIR for thermal and chemical structure analysis.

Expansion analyses of strategic petroleum reserve in Bayou Choctaw : revised locations.

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

Ehgartner, Brian L.; Park, Byoung Yoon

2010-11-01

This report summarizes a series of three-dimensional simulations for the Bayou Choctaw Strategic Petroleum Reserve. The U.S. Department of Energy plans to leach two new caverns and convert one of the existing caverns within the Bayou Choctaw salt dome to expand its petroleum reserve storage capacity. An existing finite element mesh from previous analyses is modified by changing the locations of two caverns. The structural integrity of the three expansion caverns and the interaction between all the caverns in the dome are investigated. The impacts of the expansion on underground creep closure, surface subsidence, infrastructure, and well integrity are quantified.more » Two scenarios were used for the duration and timing of workover conditions where wellhead pressures are temporarily reduced to atmospheric pressure. The three expansion caverns are predicted to be structurally stable against tensile failure for both scenarios. Dilatant failure is not expected within the vicinity of the expansion caverns. Damage to surface structures is not predicted and there is not a marked increase in surface strains due to the presence of the three expansion caverns. The wells into the caverns should not undergo yield. The results show that from a structural viewpoint, the locations of the two newly proposed expansion caverns are acceptable, and all three expansion caverns can be safely constructed and operated.« less

Northeast sector of the Greenland Ice Sheet to undergo the greatest inland expansion of supraglacial lakes during the 21st century

NASA Astrophysics Data System (ADS)

Ignéczi, Ádám.; Sole, Andrew J.; Livingstone, Stephen J.; Leeson, Amber A.; Fettweis, Xavier; Selmes, Nick; Gourmelen, Noel; Briggs, Kate

2016-09-01

The formation and rapid drainage of supraglacial lakes (SGL) influences the mass balance and dynamics of the Greenland Ice Sheet (GrIS). Although SGLs are expected to spread inland during the 21st century due to atmospheric warming, less is known about their future spatial distribution and volume. We use GrIS surface elevation model and regional climate model outputs to show that at the end of the 21st century (2070-2099) approximately 9.8 ± 3.9 km3 (+113% compared to 1980-2009) and 12.6 ± 5 km3 (+174%) of meltwater could be stored in SGLs under moderate and high representative concentration pathways (RCP 4.5 and 8.5), respectively. The largest increase is expected in the northeastern sector of the GrIS (191% in RCP 4.5 and 320% in RCP 8.5), whereas in west Greenland, where the most SGLs are currently observed, the future increase will be relatively moderate (55% in RCP 4.5 and 68% in RCP 8.5).

Cryo-EM visualization of the protein machine that replicates the chromosome

NASA Astrophysics Data System (ADS)

Li, Huilin

Structural knowledge is key to understanding biological functions. Cryo-EM is a physical method that uses transmission electron microscopy to visualize biological molecules that are frozen in vitreous ice. Due to recent advances in direct electron detector and image processing algorithm, cryo-EM has become a high-resolution technique. Cryo-EM field is undergoing a rapid expansion and vast majority research institutions and research universities around the world are setting up cryo-EM research. Indeed, the method is revolutionizing structural and molecular biology. We have been using cryo-EM to study the structure and mechanism of eukaryotic chromosome replication. Despite an abundance of cartoon drawings found in review articles and biology textbooks, the structure of the eukaryotic helicase that unwinds the double stranded DNA has been unknown. It has also been unknown how the helicase works with DNA polymerases to accomplish the feat of duplicating the genome. In my presentation, I will show how we have used cryo-EM to derive at structures of the eukaryotic chromosome replication machinery and describe mechanistic insights we have gleaned from the structures.

A high-resolution genetic signature of demographic and spatial expansion in epizootic rabies virus

PubMed Central

Biek, Roman; Henderson, J. Caroline; Waller, Lance A.; Rupprecht, Charles E.; Real, Leslie A.

2007-01-01

Emerging pathogens potentially undergo rapid evolution while expanding in population size and geographic range during the course of invasion, yet it is generally difficult to demonstrate how these processes interact. Our analysis of a 30-yr data set covering a large-scale rabies virus outbreak among North American raccoons reveals the long lasting effect of the initial infection wave in determining how viral populations are genetically structured in space. We further find that coalescent-based estimates derived from the genetic data yielded an amazingly accurate reconstruction of the known spatial and demographic dynamics of the virus over time. Our study demonstrates the combined evolutionary and population dynamic processes characterizing the spread of pathogen after its introduction into a fully susceptible host population. Furthermore, the results provide important insights regarding the spatial scale of rabies persistence and validate the use of coalescent approaches for uncovering even relatively complex population histories. Such approaches will be of increasing relevance for understanding the epidemiology of emerging zoonotic diseases in a landscape context. PMID:17470818

Study on key technologies of vehicle networking system platform for electric automobiles based on micro-service

NASA Astrophysics Data System (ADS)

Ye, Fei

2018-04-01

With the rapid increase of electric automobiles and charging piles, the elastic expansion and online rapid upgrade were required for the vehicle networking system platform (system platform for short). At present, it is difficult to meet the operation needs due to the traditional huge rock architecture used by the system platform. This paper studied the system platform technology architecture based on "cloud platform +micro-service" to obtain a new generation of vehicle networking system platform with the combination of elastic expansion and application, thus significantly improving the service operation ability of system.

Non-equilibrium scale invariance and shortcuts to adiabaticity in a one-dimensional Bose gas

PubMed Central

Rohringer, W.; Fischer, D.; Steiner, F.; Mazets, I. E.; Schmiedmayer, J.; Trupke, M.

2015-01-01

We present experimental evidence for scale invariant behaviour of the excitation spectrum in phase-fluctuating quasi-1d Bose gases after a rapid change of the external trapping potential. Probing density correlations in free expansion, we find that the temperature of an initial thermal state scales with the spatial extension of the cloud as predicted by a model based on adiabatic rescaling of initial eigenmodes with conserved quasiparticle occupation numbers. Based on this result, we demonstrate that shortcuts to adiabaticity for the rapid expansion or compression of the gas do not induce additional heating. PMID:25867640

Detection of Large Pathogenic Expansions in FRDA1, SCA10, and SCA12 Genes Using a Simple Fluorescent Repeat-Primed PCR Assay

PubMed Central

Cagnoli, Claudia; Michielotto, Chiara; Matsuura, Tohru; Ashizawa, Tetsuo; Margolis, Russell L.; Holmes, Susan E.; Gellera, Cinzia; Migone, Nicola; Brusco, Alfredo

2004-01-01

At least 18 human genetic diseases are caused by expansion of short tandem repeats. Here we describe a successful application of a fluorescent PCR method for the detection of expanded repeats in FRDA1, SCA10, and SCA12 genes. Although this test cannot give a precise estimate of the size of the expansion, it is robust, reliable, and inexpensive, and can be used to screen large series of patients. It proved useful for confirming the presence of large expansions in the Friedreich ataxia gene following an ambiguous result of long-range PCR, as well as rapid pre-screening for large repeat expansions associated with Friedreich ataxia and SCA10 and the shorter repeat expansions associated with SCA12. PMID:15096564

Coupled social and ecological outcomes of land use change and agricultural intensification in Costa Rica and the future of biodiversity conservation in tropical agricultural regions.

NASA Astrophysics Data System (ADS)

Sanfiorenzo, A. R.; Shaver, I.; Chain Guadarrama, A.; Cleary, K.; Santiago-Garcia, R.; Finegan, B.; Hormel, L.; Sibelet, N.; Vierling, L. A.; Bosque-Perez, N.; DeClerck, F.; Fagan, M. E.; Waits, L.

2016-12-01

Tropical ecosystem conversion to agriculture has caused widespread habitat loss and created fragmented landscapes composed of remnant forest patches embedded in a matrix of agricultural land uses. Non- traditional agricultural export (NTAE) crops such as pineapple are rapidly replacing multiuse landscapes characterized by a diverse matrix of pasture and smallholder crops with intensive, large-scale, monoculture plantations. Using an interdisciplinary approach, we conduct a case study to examine the coupled social and ecological implications of LUCC and agricultural intensification in this region, with larger application to regions experiencing similar patterns. Guided by frameworks from both political and landscape ecology, we: (1) describe the social and economic implications of pineapple expansion, specifically the concentration of land, labor and financial resources, (2) quantify pineapple cultivation's spatial characteristics, and (3) assess the effects of pineapple expansion on surrounding forest ecosystems, on the agricultural matrix and on biodiversity conservation. Our results indicate that pineapple production concentrates land, labor, and financial resources, which has a homogenizing effect on the agricultural economy in the study region. This constrains farm-based livelihoods, with larger implications for food security and agricultural diversity. Landscape ecology analyses further reveal how pineapple production simplifies and homogenizes the agricultural matrix between forest patches, which is likely to have a negative effect on biodiversity. To offset the effects of pineapple expansion on social and environmental systems, we recommend developing landscape level land use planning capacity. Furthermore, agricultural and conservation policy reform is needed to promote landscape heterogeneity and economic diversity within the agricultural sector. Our interdisciplinary research provides a detailed examination of the social and ecological impacts of agricultural intensification in a tropical landscape, and offers recommendations for improvement relevant not only to our study region but to the many other tropical landscapes currently undergoing non-traditional agricultural export driven agricultural intensification.

Coupled social and ecological outcomes of land use change and agricultural intensification in Costa Rica and the future of biodiversity conservation in tropical agricultural regions.

NASA Astrophysics Data System (ADS)

Sanfiorenzo, A. R.; Shaver, I.; Chain Guadarrama, A.; Cleary, K.; Santiago-Garcia, R.; Finegan, B.; Hormel, L.; Sibelet, N.; Vierling, L. A.; Bosque-Perez, N.; DeClerck, F.; Fagan, M. E.; Waits, L.

2017-12-01

Tropical ecosystem conversion to agriculture has caused widespread habitat loss and created fragmented landscapes composed of remnant forest patches embedded in a matrix of agricultural land uses. Non- traditional agricultural export (NTAE) crops such as pineapple are rapidly replacing multiuse landscapes characterized by a diverse matrix of pasture and smallholder crops with intensive, large-scale, monoculture plantations. Using an interdisciplinary approach, we conduct a case study to examine the coupled social and ecological implications of LUCC and agricultural intensification in this region, with larger application to regions experiencing similar patterns. Guided by frameworks from both political and landscape ecology, we: (1) describe the social and economic implications of pineapple expansion, specifically the concentration of land, labor and financial resources, (2) quantify pineapple cultivation's spatial characteristics, and (3) assess the effects of pineapple expansion on surrounding forest ecosystems, on the agricultural matrix and on biodiversity conservation. Our results indicate that pineapple production concentrates land, labor, and financial resources, which has a homogenizing effect on the agricultural economy in the study region. This constrains farm-based livelihoods, with larger implications for food security and agricultural diversity. Landscape ecology analyses further reveal how pineapple production simplifies and homogenizes the agricultural matrix between forest patches, which is likely to have a negative effect on biodiversity. To offset the effects of pineapple expansion on social and environmental systems, we recommend developing landscape level land use planning capacity. Furthermore, agricultural and conservation policy reform is needed to promote landscape heterogeneity and economic diversity within the agricultural sector. Our interdisciplinary research provides a detailed examination of the social and ecological impacts of agricultural intensification in a tropical landscape, and offers recommendations for improvement relevant not only to our study region but to the many other tropical landscapes currently undergoing non-traditional agricultural export driven agricultural intensification.

Conformational changes in intact dengue virus reveal serotype-specific expansion

PubMed Central

Lim, Xin-Xiang; Chandramohan, Arun; Lim, Xin Ying Elisa; Bag, Nirmalya; Sharma, Kamal Kant; Wirawan, Melissa; Wohland, Thorsten; Lok, Shee-Mei; Anand, Ganesh S.

2017-01-01

Dengue virus serotype 2 (DENV2) alone undergoes structural expansion at 37 °C (associated with host entry), despite high sequence and structural homology among the four known serotypes. The basis for this differential expansion across strains and serotypes is unknown and necessitates mapping of the dynamics of dengue whole viral particles to describe their coordinated motions and conformational changes when exposed to host-like environments. Here we capture the dynamics of intact viral particles of two serotypes, DENV1 and DENV2, by amide hydrogen/deuterium exchange mass spectrometry (HDXMS) and time resolved Förster Resonance Energy Transfer. Our results show temperature-dependent dynamics hotspots on DENV2 and DENV1 particles with DENV1 showing expansion at 40 °C but not at 37 °C. HDXMS measurement of virion dynamics in solution offers a powerful approach to identify potential epitopes, map virus-antibody complex structure and dynamics, and test effects of multiple host-specific perturbations on viruses and virus-antibody complexes. PMID:28186093

Development of rat female genital cortex and control of female puberty by sexual touch

PubMed Central

Lenschow, Constanze; Sigl-Glöckner, Johanna

2017-01-01

Rat somatosensory cortex contains a large sexually monomorphic genital representation. Genital cortex undergoes an unusual 2-fold expansion during puberty. Here, we investigate genital cortex development and female rat sexual maturation. Ovariectomies and estradiol injections suggested sex hormones cause the pubertal genital cortex expansion but not its maintenance at adult size. Genital cortex expanded by thalamic afferents invading surrounding dysgranular cortex. Genital touch was a dominant factor driving female sexual maturation. Raising female rats in contact with adult males promoted genital cortex expansion, whereas contact to adult females or nontactile (audio-visual-olfactory) male cues did not. Genital touch imposed by human experimenters powerfully advanced female genital cortex development and sexual maturation. Long-term blocking of genital cortex by tetrodotoxin in pubescent females housed with males prevented genital cortex expansion and decelerated vaginal opening. Sex hormones, sexual experience, and neural activity shape genital cortex, which contributes to the puberty promoting effects of sexual touch. PMID:28934203

Development of rat female genital cortex and control of female puberty by sexual touch.

PubMed

Lenschow, Constanze; Sigl-Glöckner, Johanna; Brecht, Michael

2017-09-01

Rat somatosensory cortex contains a large sexually monomorphic genital representation. Genital cortex undergoes an unusual 2-fold expansion during puberty. Here, we investigate genital cortex development and female rat sexual maturation. Ovariectomies and estradiol injections suggested sex hormones cause the pubertal genital cortex expansion but not its maintenance at adult size. Genital cortex expanded by thalamic afferents invading surrounding dysgranular cortex. Genital touch was a dominant factor driving female sexual maturation. Raising female rats in contact with adult males promoted genital cortex expansion, whereas contact to adult females or nontactile (audio-visual-olfactory) male cues did not. Genital touch imposed by human experimenters powerfully advanced female genital cortex development and sexual maturation. Long-term blocking of genital cortex by tetrodotoxin in pubescent females housed with males prevented genital cortex expansion and decelerated vaginal opening. Sex hormones, sexual experience, and neural activity shape genital cortex, which contributes to the puberty promoting effects of sexual touch.

Microbend fiber-optic temperature sensor

DOEpatents

Weiss, J.D.

1995-05-30

A temperature sensor is made of optical fiber into which quasi-sinusoidal microbends have been permanently introduced. In particular, the present invention includes a graded-index optical fiber directing steady light through a section of the optical fiber containing a plurality of permanent microbends. The microbend section of the optical fiber is contained in a thermally expansive sheath, attached to a thermally expansive structure, or attached to a bimetallic element undergoing temperature changes and being monitored. The microbend section is secured to the thermally expansive sheath which allows the amplitude of the microbends to decrease with temperature. The resultant increase in the optical fiber`s transmission thus allows temperature to be measured. The plural microbend section of the optical fiber is secured to the thermally expansive structure only at its ends and the microbends themselves are completely unconstrained laterally by any bonding agent to obtain maximum longitudinal temperature sensitivity. Although the permanent microbends reduce the transmission capabilities of fiber optics, the present invention utilizes this phenomenon as a transduction mechanism which is optimized to measure temperature. 5 figs.

Microbend fiber-optic temperature sensor

DOEpatents

Weiss, Jonathan D.

1995-01-01

A temperature sensor is made of optical fiber into which quasi-sinusoidal microbends have been permanently introduced. In particular, the present invention includes a graded-index optical fiber directing steady light through a section of the optical fiber containing a plurality of permanent microbends. The microbend section of the optical fiber is contained in a thermally expansive sheath, attached to a thermally expansive structure, or attached to a bimetallic element undergoing temperature changes and being monitored. The microbend section is secured to the thermally expansive sheath which allows the amplitude of the microbends to decrease with temperature. The resultant increase in the optical fiber's transmission thus allows temperature to be measured. The plural microbend section of the optical fiber is secured to the thermally expansive structure only at its ends and the microbends themselves are completely unconstrained laterally by any bonding agent to obtain maximum longitudinal temperature sensitivity. Although the permanent microbends reduce the transmission capabilities of fiber optics, the present invention utilizes this phenomenon as a transduction mechanism which is optimized to measure temperature.

CD134/CD137 Dual Costimulation-Elicited IFN-γ Maximizes Effector T Cell Function but Limits Treg Expansion

PubMed Central

Rose, Marie-Clare St.; Taylor, Roslyn A.; Bandyopadhyay, Suman; Qui, Harry Z.; Hagymasi, Adam T.; Vella, Anthony T.; Adler, Adam J.

2012-01-01

T cell tolerance to tumor antigens represents a major hurdle in generating tumor immunity. Combined administration of agonistic monoclonal antibodies to the costimulatory receptors CD134 plus CD137 can program T cells responding to tolerogenic antigen to undergo expansion and effector T cell differentiation, and also elicits tumor immunity. Nevertheless, CD134 and CD137 agonists can also engage inhibitory immune components. To understand how immune stimulatory versus inhibitory components are regulated during CD134 plus CD137 dual costimulation, the current study utilized a model where dual costimulation programs T cells encountering a highly tolerogenic self-antigen to undergo effector differentiation. IFN-γ was found to play a pivotal role in maximizing the function of effector T cells while simultaneously limiting the expansion of CD4+CD25+Foxp3+ Tregs. In antigen-responding effector T cells, IFN-γ operates via a direct cell-intrinsic mechanism to cooperate with IL-2 to program maximal expression of granzyme B. Simultaneously, IFN-γ limits expression of the IL-2 receptor alpha chain (CD25) and IL-2 signaling through a mechanism that does not involve T-bet-mediated repression of IL-2. IFN-γ also limited CD25 and Foxp3 expression on bystanding CD4+Foxp3+ Tregs, and limited the potential of these Tregs to expand. These effects could not be explained by the ability of IFN-γ to limit IL-2 availability. Taken together, during dual costimulation IFN-γ interacts with IL-2 through distinct mechanisms to program maximal expression of effector molecules in antigen-responding T cells while simultaneously limiting Treg expansion. PMID:23295363

Understanding the Persistence of Inequality in Higher Education: Evidence from Australia

ERIC Educational Resources Information Center

Chesters, Jenny; Watson, Louise

2013-01-01

During the latter half of the twentieth century, Australia, like many countries in the Organisation for Economic Cooperation and Development, experienced rapid expansion in participation in higher education which was supported by government through increases in the number of publicly funded university places. However, in spite of this expansion, a…

Dendritic Cells Control Fibroblastic Reticular Network Tension and Lymph Node Expansion

PubMed Central

Acton, Sophie E.; Farrugia, Aaron J.; Astarita, Jillian L.; Mourão-Sá, Diego; Jenkins, Robert P.; Nye, Emma; Hooper, Steven; van Blijswijk, Janneke; Rogers, Neil C.; Snelgrove, Kathryn J.; Rosewell, Ian; Moita, Luis F.; Stamp, Gordon; Turley, Shannon J.; Sahai, Erik; Sousa, Caetano Reis e

2014-01-01

Following immunogenic challenge, infiltrating and dividing lymphocytes significantly increase lymph node (LN) cellularity leading to organ expansion1,2. Here we report that the physical elasticity of LNs is maintained in part by podoplanin (PDPN) signalling in stromal fibroblastic reticular cells (FRCs) and its modulation by CLEC-2 expressed on dendritic cells (DCs). We show that PDPN induces actomyosin contractility in FRCs via activation of RhoA/C and downstream Rho-kinase. Engagement by CLEC-2 causes PDPN clustering and rapidly uncouples PDPN from RhoA/C activation, relaxing the actomyosin cytoskeleton and permitting FRC stretching. Notably, administration of CLEC-2 protein to immunised mice augments LN expansion. In contrast, the latter is significantly constrained in mice selectively lacking CLEC-2 expression in DCs. Thus, the same DCs that initiate immunity by presenting antigens to T lymphocytes3 also initiate remodeling of LNs by delivering CLEC-2 to FRCs. CLEC-2 modulation of PDPN signalling permits FRC network stretching and allows for the rapid LN expansion driven by lymphocyte influx and proliferation that is the critical hallmark of adaptive immunity. PMID:25341788

Evolution on the move: specialization on widespread resources associated with rapid range expansion in response to climate change.

PubMed

Bridle, Jon R; Buckley, James; Bodsworth, Edward J; Thomas, Chris D

2014-02-07

Generalist species and phenotypes are expected to perform best under rapid environmental change. In contrast to this view that generalists will inherit the Earth, we find that increased use of a single host plant is associated with the recent climate-driven range expansion of the UK brown argus butterfly. Field assays of female host plant preference across the UK reveal a diversity of adaptations to host plants in long-established parts of the range, whereas butterflies in recently colonized areas are more specialized, consistently preferring to lay eggs on one host plant species that is geographically widespread throughout the region of expansion, despite being locally rare. By common-garden rearing of females' offspring, we also show an increase in dispersal propensity associated with the colonization of new sites. Range expansion is therefore associated with an increase in the spatial scale of adaptation as dispersive specialists selectively spread into new regions. Major restructuring of patterns of local adaptation is likely to occur across many taxa with climate change, as lineages suited to regional colonization rather than local success emerge and expand.

Virtual Genomes in Flux: An Interplay of Neutrality and Adaptability Explains Genome Expansion and Streamlining

PubMed Central

Cuypers, Thomas D.; Hogeweg, Paulien

2012-01-01

The picture that emerges from phylogenetic gene content reconstructions is that genomes evolve in a dynamic pattern of rapid expansion and gradual streamlining. Ancestral organisms have been estimated to possess remarkably rich gene complements, although gene loss is a driving force in subsequent lineage adaptation and diversification. Here, we study genome dynamics in a model of virtual cells evolving to maintain homeostasis. We observe a pattern of an initial rapid expansion of the genome and a prolonged phase of mutational load reduction. Generally, load reduction is achieved by the deletion of redundant genes, generating a streamlining pattern. Load reduction can also occur as a result of the generation of highly neutral genomic regions. These regions can expand and contract in a neutral fashion. Our study suggests that genome expansion and streamlining are generic patterns of evolving systems. We propose that the complex genotype to phenotype mapping in virtual cells as well as in their biological counterparts drives genome size dynamics, due to an emerging interplay between adaptation, neutrality, and evolvability. PMID:22234601

Bone-anchored maxillary expansion and bilateral interoral mandibular distraction osteogenesis in adult with severe obstructive sleep apnea syndrome.

PubMed

Nie, Ping; Zhu, Min; Lu, Xiao-Feng; Fang, Bing

2013-05-01

Severe obstructive sleep apnea syndrome (OSAS) threatens patients' lives. To solve ventilation problem, snoring, and avoid another orthognathic surgery for mandibular advancement, bone-anchored rapid maxillary expansion and bilateral interoral mandibular distraction osteogenesis were tried on a 20-year-old Chinese male patient with severe skeletal class II malocclusion and OSAS.The patient had polysomnography (apnea-hypopnea index 54.2), body mass index measurement (19.7 kg/m), and cephalometry before the treatment. Bone-anchored rapid maxillary expansion was performed for the correction of maxillary transverse and minor sagittal deficiency and the improvement of nasal airflow by decreasing nasal resistance. Bilateral interoral mandibular distraction osteogenesis was operated to lengthen the small, retruded mandible by 15 mm. Orthodontic treatment after the maxillary expansion and mandibular distraction osteogenesis can help obtain stable occlusion.The Epworth Sleepiness Scale, a questionnaire for temporomandibular joint, cephalometric analysis, polysomnography, acoustic rhinometry, and multislice spiral computed tomography were performed to evaluate changes from the treatment. All the results showed that the patient had a significantly alleviated OSAS. In addition, an acceptable occlusion was also obtained.

Region V Transportation Workforce Assessment and Summit

DOT National Transportation Integrated Search

2017-05-01

The transportation workforce is undergoing unprecedented change due to rapid retirement of baby boomers while at the same time information, communication, and automation technologies are rapidly changing the transportation of people and goods. The pu...

Foraminiferal Range Expansions: The Mediterranean Sea as a natural laboratory for climate induced invasions

NASA Astrophysics Data System (ADS)

Hortense Mouanga, Gloria; Langer, Martin R.

2015-04-01

Climate change and biological invasions are key processes that modify biodiversity. One of the most severely affected areas of global change is the Mediterranean Sea, where global warming and the opening of the Suez Canal triggered a mass invasion of tropical Red Sea taxa into Mediterranean territories. Climate models prognosticate that the Mediterranean Sea will be one of the most affected ocean regions and may thus serve as a natural laboratory of future global changes. Among the key taxa that are rapidly expanding their latitudinal range in the Mediterranean Sea are symbiont-bearing foraminifera of the genus Amphistegina. Their range expansion strongly correlates with rising sea surface temperatures and mirrors processes of global change. Amphisteginid foraminifera are among the most prolific foraminiferal species and contribute significantly to shallow-water carbonate sediments. Given their prominent environmental role, rapid biogeographic range expansion, and impact on native ecosystems, amphisteginid range expansion and invasion into new territory are likely to trigger changes in ecosystem functioning. Among the uncertainties, it is not known whether all parts of the Mediterranean will be affected equally and to what extent amphisteginid invasions will impact native biotas. We have initiated a new baseline study to explore the effects of invasive amphisteginids on native foraminiferal biotas and to monitor expansion rates and effects on ecosystem functioning along the current range expansion front. We will present new data on recent shift along the range expansion front and discuss cascading effects on community structures and species richness of native foraminiferal biotas. The magnitude and effects that climate change will have on the Mediterranean foraminiferal faunas may ultimately serve as an example of what would happen along expansion fronts in global oceans.

Atmospheric Oxygen Inhibits Growth and Differentiation of Marrow-Derived Mouse Mesenchymal Stem Cells via a p53 Dependent Mechanism: Implications for Long-Term Culture Expansion

PubMed Central

Boregowda, Siddaraju; Krishnappa, Veena; Chambers, Jeremy; LoGrasso, Phillip V.; Lai, Wen-Tzu; Ortiz, Luis A.; Phinney, Donald G.

2013-01-01

Large scale expansion of human mesenchymal stem cells (MSCs) is routinely performed for clinical therapy. In contrast, developing protocols for large scale expansion of primary mouse MSCs has been more difficult due to unique aspects of rodent biology. Currently, established methods to isolate mouse MSCs select for rapidly dividing subpopulations that emerge from bone marrow cultures following long-term (months) expansion in atmospheric oxygen. Herein, we demonstrate that exposure to atmospheric oxygen rapidly induced p53, TOP2A and BAX expression and mitochondrial ROS generation in primary mouse MSCs resulting in oxidative stress, reduced cell viability and inhibition of cell proliferation. Alternatively, procurement and culture in 5% oxygen supported more prolific expansion of the CD45−ve/CD44+ve cell fraction in marrow, produced increased MSC yields following immuno-depletion, and supported sustained MSC growth resulting in a 2300-fold increase in cumulative cell yield by 4th passage. MSCs cultured in 5% oxygen also exhibited enhanced tri-lineage differentiation. The oxygen-induced stress response was dependent upon p53 since siRNA mediated knockdown of p53 in wild type cells or exposure of p53−/− MSCs to atmospheric oxygen failed to induce ROS generation, reduce viability, or arrest cell growth. These data indicate that long-term culture expansion of mouse MSCs in atmospheric oxygen selects for clones with absent or impaired p53 function, which allows cells to escape oxygen-induced growth inhibition. In contrast, expansion in 5% oxygen generates large numbers of primary mouse MSCs that retain sensitivity to atmospheric oxygen, and therefore a functional p53 protein, even after long-term expansion in vitro. PMID:22367737

Surgically Assisted Rapid Palatomaxillary Expansion With or Without Pterygomaxillary Disjunction: A Systematic Review and Meta-Analysis.

PubMed

Hamedi Sangsari, Adrien; Sadr-Eshkevari, Pooyan; Al-Dam, Ahmed; Friedrich, Reinhard E; Freymiller, Earl; Rashad, Ashkan

2016-02-01

The purpose of this review was to evaluate the outcome measurements of anterior expansion, posterior expansion, and complications after surgically assisted rapid palatal expansion (SARPE) with or without pterygomaxillary disjunction (PMD). A computerized database search was performed using PubMed, CINAHL, Cochrane, Scopus, and Web of Science. Then, a computerized search was conducted in Google Scholar and ProQuest to overcome publication bias. From the original 125 combined results, 3 met the inclusion criteria. The Quality Assessment Tool for Quantitative Studies of the Effective Public Health Practice Project assessed 2 articles as weak and 1 as moderate. The systematic review included a total of 48 patients (11 male and 37 female). For 25 patients, SARPE was performed with PMD and for 23 patients SARPE was performed without PMD. A tooth-borne fixed hyrax-type palatal expansion screw appliance was used for all cases, activated 1 to 2 mm intraoperatively, and, after a latency period of 3 to 7 days, activated 0.5 to 0.6 mm per day for 38 patients and 0.25 mm for the other 10 until adequate expansion. Postexpansion retention was performed using ligature wired hyrax in 18 patients for 4 months. Comparisons were based on cone-beam computed tomographic projections, study models only, or a combination of study models, anteroposterior cephalometric radiographs, and occlusal radiographs. The time to measure the changes ranged from before fixed orthodontic retention to 6 months after the completion of active expansion. A meta-analysis was possible only for anterior (intercanine) and posterior (inter-molar) dental expansions. The literature is inconclusive regarding the effect of PMD on the outcomes of SARPE. Further controlled trials are needed. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

77 FR 61012 - Expansion of Importer Self-Assessment Program To Include Qualified Importers of Focused...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

...-Assessment Program To Include Qualified Importers of Focused Assessment Audits AGENCY: U.S. Customs and... undergoing comprehensive CBP audits. This document announces that a company that has successfully undergone a CBP Focused Assessment (FA) audit may be eligible to transition into the ISA program without further...

Analysis of the thermal expansivity near the tricritical point in dilute chromium alloys

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

Yurtseven, H., E-mail: hamit@metu.edu.tr; Tari, Ö., E-mail: ozlemilgin@arel.edu.tr

Chromium (Cr) undergoes a first order Neel transition as an antiferromagnetic material. When V, Mo and Mn atoms are substituted in the Cr lattice, a weak first order Neel transition in pure Cr changes toward a second order transition and a possible tricritical point in CrV occurs close to 0.2 at %V, as observed experimentally from the measurements of the thermal expansivity at various temperatures. In this study, we analyze the experimental data for the thermal expansivity from the literature as a function of temperature using the power - law formula for Cr alloys (Cr - 0.1V, 0.2V, 0.5V andmore » Cr - 0.1Mn, Cr - 0.2Mo, 0.3Mo, 0.4Mo). Our results are interpreted near the tricritical point in dilute chromium alloys.« less

Rapid and reversible photoinduced switching of a rotaxane crystal

NASA Astrophysics Data System (ADS)

Chen, Kai-Jen; Tsai, Ya-Ching; Suzaki, Yuji; Osakada, Kohtaro; Miura, Atsushi; Horie, Masaki

2016-11-01

Crystalline phase transitions caused by external stimuli have been used to detect physical changes in the solid-state properties. This study presents the mechanical switching of crystals of ferrocene-containing rotaxane controlled by focused laser light. The expansion and contraction of the crystals can be driven by turning on and off laser light at 445 nm. The irradiation-induced expansion of the crystal involves elongation along the a, b and c axes at 30 °C, whereas heating of the crystal at 105 °C causes the shortening of c axis. The expansions reversibly occur and have the advantage of a rapid relaxation (reverse) process. Single-crystal X-ray crystallography reveals the detailed structural changes of the molecules, corresponding to a change in the size of the crystals on laser irradiation. This molecular crystal behaviour induced by laser irradiation, is demonstrated for the remote control of objects, namely, microparticle transport and microswitching in an electric circuit.

IL-7–dependent STAT1 activation limits homeostatic CD4+ T cell expansion

PubMed Central

Le Saout, Cecile; Luckey, Megan A.; Villarino, Alejandro V.; Smith, Mindy; Hasley, Rebecca B.; Myers, Timothy G.; Imamichi, Hiromi; Park, Jung-Hyun; O’Shea, John J.; Lane, H. Clifford

2017-01-01

IL-7 regulates homeostatic mechanisms that maintain the overall size of the T cell pool throughout life. We show that, under steady-state conditions, IL-7 signaling is principally mediated by activation of signal transducers and activators of transcription 5 (STAT5). In contrast, under lymphopenic conditions, there is a modulation of STAT1 expression resulting in an IL-7–dependent STAT1 and STAT5 activation. Consequently, the IL-7–induced transcriptome is altered with enrichment of IFN-stimulated genes (ISGs). Moreover, STAT1 overexpression was associated with reduced survival in CD4+ T cells undergoing lymphopenia-induced proliferation (LIP). We propose a model in which T cells undergoing LIP upregulate STAT1 protein, “switching on” an alternate IL-7–dependent program. This mechanism could be a physiological process to regulate the expansion and size of the CD4+ T cell pool. During HIV infection, the virus could exploit this pathway, leading to the homeostatic dysregulation of the T cell pools observed in these patients. PMID:29202461

Out of the black box: expansion of a theory-based intervention to self-manage the uncertainty associated with active surveillance (AS) for prostate cancer.

PubMed

Kazer, Meredith Wallace; Bailey, Donald E; Whittemore, Robin

2010-01-01

Active surveillance (AS) (sometimes referred to as watchful waiting) is an alternative approach to managing low-risk forms of prostate cancer. This management approach allows men to avoid expensive prostate cancer treatments and their well-documented adverse events of erectile dysfunction and incontinence. However, AS is associated with illness uncertainty and reduced quality of life (QOL; Wallace, 2003). An uncertainty management intervention (UMI) was developed by Mishel et al. (2002) to manage uncertainty in women treated for breast cancer and men treated for prostate cancer. However, the UMI was not developed for men undergoing AS for prostate cancer and has not been adequately tested in this population. This article reports on the expansion of a theory-based intervention to manage the uncertainty associated with AS for prostate cancer. Intervention Theory (Sidani & Braden, 1998) is discussed as a framework for revising the UMI intervention for men undergoing AS for prostate cancer (UMI-AS). The article concludes with plans for testing of the expanded intervention and implications for the extended theory.

Built-up Land Expansion in Urban China

NASA Astrophysics Data System (ADS)

Chen, Yi; Chen, Zhigang; Huang, Xianjin

2017-04-01

Since the implementation of the reform and opening-up, rapid expansion of built-up land has caused a rapid reduction of arable land. The Ministry of Land and Resources of the People' s Republic of China has strengthened the management of built-up land through the basic arable land protection and the quota allocation of built-up land to control the urban sprawl. In addition, the general land use planning and the annual land use plan have been used to further ensure the effectiveness of land use management and control. However, the trend of built-up land expansion has not been effectively restrained. The built-up land expansion increased from 31.92 × 106 hm2 in 2005 to 38.89 × 106 hm2 in 2012. The rapid expansion of built-up land has been the major feature of land use changes in China and has led to built-up land vacancy and inefficient land use. This paper used a Data Envelopment Analysis (DEA) model to analyze the changes in built-up land efficiency in 336 cities in China from 2005 to 2012 during the implementation of National General Land Use Plan (2006-2020) (NGLUP). The results showed that the built-up land input-output efficiency of most cities declined, and more than half of the cities had excessive inputs of built-up land. Even in the most developed region of China, the built-up land efficiency was relatively low. The paper argues that the NGLUP failed to control the expansion of built-up land and to promote intensive land use. The allocation of built-up land designated by the Plan was not reasonable, and economic development has greatly relied on land inputs, which need to be improved. The paper finally suggests that the built-up land indices should be appropriately directed toward economically underdeveloped regions in central and western China, and the establishment of a withdrawal mechanism for inefficient land would better promote the efficient allocation of built-up land.

Effect of Royal Jelly on new bone formation in rapid maxillary expansion in rats.

PubMed

Özan, Fatih; Çörekçi, Bayram; Toptaş, Orçun; Halicioğlu, Koray; Irgin, Celal; Yilmaz, Fahri; Hezenci, Yasin

2015-11-01

The aim of this study was to evaluate the effects of long and short term systemic usage of royal jelly on bone formation in the expanded maxillary suture in a rat model. Twenty eight Wistar albino rats were randomly divided into 4 equal groups: Control (C); Only Expansion (OE), Royal Jelly (RJ) group, Royal Jelly was given to rats by oral gavage only during the expansion and retention period; Royal Jelly plus Nursery (RJN) group, Royal Jelly was given to rats by oral gavage during their nursery phase of 40 days and during the retention period. After the 5 day expansion period was completed, the rats underwent 12 days of mechanical retention. All rats were sacrificed in same time. Histological examination was performed to determine the number of osteoclasts, number of osteoblasts, number of capillaries, inflammatory cell infiltration, and new bone formation. New bone formation, number of osteoclasts, number of osteoblasts, and the number of capillaries in the expanded maxillary sutures were higher in the RJ and RJN groups than in the other groups. Statistical analysis also demonstrated that new bone formation and the number of osteoblasts was also highest in the RJN group. The systemic administration of Royal Jelly in conjunction with rapid maxillary expansion may increase the quality of regenerated bone.

Oil Palm expansion over Southeast Asia: land use change and air quality

NASA Astrophysics Data System (ADS)

Silva, S. J.; Heald, C. L.; Geddes, J.; Marlier, M. E.; Austin, K.; Kasibhatla, P. S.

2015-12-01

Over recent decades oil palm plantations have rapidly expanded across Southeast Asia (SEA). Much of this expansion has come at the expense of natural forests and grasslands. Aircraft measurements from a 2008 campaign, OP3, found that oil palm plantations emit as much as 7 times more isoprene than nearby natural forests. Furthermore, SEA is a rapidly developing region, with increasing urban population, and growing air quality concerns. Thus, SEA represents an ideal case study to examine the impacts of land use change on air quality in the region, and whether those changes can be detected from satellite observations of atmospheric composition. We investigate the impacts of historical and future oil palm expansion in SEA using satellite data, high-resolution land maps, and the chemical transport model GEOS-Chem. We examine the impact of palm plantations on surface-atmosphere processes (dry deposition, biogenic emissions). We show the sensitivity of air quality to current and future oil palm expansion scenarios, and discuss the limitations of current satellite measurements in capturing these changes. Our results indicate that while the impact of oil palm expansion on air quality can be significant, the retrieval error and sensitivity of the satellite measurements limit our ability to observe these impacts from space.

Monitoring the Invasion of Spartina alterniflora from 1993 to 2014 with Landsat TM and SPOT 6 Satellite Data in Yueqing Bay, China

PubMed Central

Wang, Anqi; Chen, Jiadai; Jing, Changwei; Ye, Guanqiong; Wu, Jiaping; Huang, Zhixing; Zhou, Chaosheng

2015-01-01

The exotic plant Spartina alterniflora was introduced to Yueqing Bay more than 20 years ago for tidal land reclamation and as a defense against typhoons, but it has rapidly expanded and caused enormous ecological consequences. Mapping the spread and distribution of S. alterniflora is the first step toward understanding the factors that determine the population expansion patterns. Remote sensing is a promising tool to monitor the expansion of S. alterniflora. Twelve Landsat TM images and Support Vector Machine (SVM) were used to delineate the invasion of S. alterniflora from 1993 to 2009, and SPOT 6 images and Object-Based Image Analysis (OBIA) were used to map the distribution of S. alterniflora in 2014. In situ data and Unmanned Aerial Vehicle (UAV) images were used as supplementary data. S. alterniflora spread rapidly in Yueqing Bay over the past 21 years. Between 1993 and 2009, the area of S. alterniflora increased by 608 times (from 4 to 2432 ha). The rapid expansion of S. alterniflora covered almost all of the bare mudflats around the mangrove forests and the cultivated mudflats. However, from 2009 to 2014, the rate of expansion of S. alterniflora began to slow down in Yueqing Bay, and the total area of S. alterniflora in Yantian decreased by 275 ha. These phenomena can be explained by the landscape changes and ecological niches. Through the expansion of S. alterniflora, it was found that the ecological significance and environmental impact of S. alterniflora was different in different regions in Yueqing Bay. The conservation plans for Yueqing Bay should consider both the positive and negative effects of S. alterniflora, and the governmental policy should be based on the different circumstances of the regions. PMID:26263172

Monitoring the Invasion of Spartina alterniflora from 1993 to 2014 with Landsat TM and SPOT 6 Satellite Data in Yueqing Bay, China.

PubMed

Wang, Anqi; Chen, Jiadai; Jing, Changwei; Ye, Guanqiong; Wu, Jiaping; Huang, Zhixing; Zhou, Chaosheng

2015-01-01

The exotic plant Spartina alterniflora was introduced to Yueqing Bay more than 20 years ago for tidal land reclamation and as a defense against typhoons, but it has rapidly expanded and caused enormous ecological consequences. Mapping the spread and distribution of S. alterniflora is the first step toward understanding the factors that determine the population expansion patterns. Remote sensing is a promising tool to monitor the expansion of S. alterniflora. Twelve Landsat TM images and Support Vector Machine (SVM) were used to delineate the invasion of S. alterniflora from 1993 to 2009, and SPOT 6 images and Object-Based Image Analysis (OBIA) were used to map the distribution of S. alterniflora in 2014. In situ data and Unmanned Aerial Vehicle (UAV) images were used as supplementary data. S. alterniflora spread rapidly in Yueqing Bay over the past 21 years. Between 1993 and 2009, the area of S. alterniflora increased by 608 times (from 4 to 2432 ha). The rapid expansion of S. alterniflora covered almost all of the bare mudflats around the mangrove forests and the cultivated mudflats. However, from 2009 to 2014, the rate of expansion of S. alterniflora began to slow down in Yueqing Bay, and the total area of S. alterniflora in Yantian decreased by 275 ha. These phenomena can be explained by the landscape changes and ecological niches. Through the expansion of S. alterniflora, it was found that the ecological significance and environmental impact of S. alterniflora was different in different regions in Yueqing Bay. The conservation plans for Yueqing Bay should consider both the positive and negative effects of S. alterniflora, and the governmental policy should be based on the different circumstances of the regions.

PHOTOSENSITIVE 2,5-DISTYRYLPYRAZINE PARTICLES PRODUCED FROM RAPID EXPANSION OF SUPERCRITICAL SOLUTIONS. (R826648)

EPA Science Inventory

Solvent-free, photoreactive particles of 2,5-distyrylpyrazine (DSP) monomer were developed by rapid precipitation from an expanding supercritical chlorodifluoromethane solution. DSP polymer particles were produced by solid-state photopolymerization. DSP particles below a criti...

Safety and Automated Train Control for Rail Rapid Transit Systems

DOT National Transportation Integrated Search

1974-07-01

The anticipated construction and expansion of rail rapid transit system in the United States over the next 10-15 years implies major capital expenditures. A significant level of automation in train cntrol is likely to be central to these systems. The...

Urban Landscape Spatial Pattern Estimation of Cities in Shandong Province Using Nighttime Luminosity Data

NASA Astrophysics Data System (ADS)

Fan, J.; He, H.; Hu, T.; Li, G.; Gao, H.; Zhao, X.

2017-09-01

China's cities have been undergoing rapid and intense urbanization processes in the past few decades. Shandong is a coastal province which is located in East China with big economy and population scales, and which also plays an important role in the rapid process of China's modernization. The DMSP/OLS dataset has been widely used for the urban development assessments in long time-series and large spatial scales situations. In this paper, we used a time series of nighttime light data to estimate the landscape spatial pattern changes of cities in Shandong province from 1994 to 2012. Nine landscape metrics were calculated and analyzed to figure out the spatial patterns of urban area developments of the cities in Shandong province. The landscape metrics include the number of patches (NP), the landscape total area (TA), the aggregation index (AI), the largest patch index (LPI), the mean patch area (AREA_MN), the landscape shape index (LSI), the total edge length (TE), the edge density (ED), and the mean radius of gyration (GYRATE_MN). The experimental results reveal that, in 1994-2012, the total urban area of cities in Shandong province expanded for 1.17 times, the average urban area increased by about 93.00%, the average annual growth rate of the TE metric is 2.67 %, while the ED metric decreased about 1.44 % annually. Bigger cities in this area show relative slower urbanization development processes, such as Jinan and Qingdao. Coastal cities represented much more rapid expansion velocities than inland cities. In the middle area of Shandong province, the connectivity between developed urban areas was constantly increased.

Effects of hydration in contrast-induced acute kidney injury after primary angioplasty: a randomized, controlled trial.

PubMed

Maioli, Mauro; Toso, Anna; Leoncini, Mario; Micheletti, Carlo; Bellandi, Francesco

2011-10-01

Intravascular volume expansion represents a beneficial measure against contrast-induced acute kidney injury (CI-AKI) in patients undergoing elective angiographic procedures. However, the efficacy of this preventive strategy has not yet been established for patients with ST-elevation-myocardial infarction (STEMI), who are at higher risk of this complication after primary percutaneous coronary intervention (PCI). In this randomized study we investigated the possible beneficial role of periprocedural intravenous volume expansion and we compared the efficacy of 2 different hydration strategies in patients with STEMI undergoing primary PCI. We randomly assigned 450 STEMI patients to receive (1) preprocedure and postprocedure hydration of sodium bicarbonate (early hydration group), (2) postprocedure hydration of isotonic saline (late hydration group), or (3) no hydration (control group). The primary end point was the development of CI-AKI, defined as an increase in serum creatinine of ≥25% or 0.5 mg/dL over the baseline value within 3 days after administration of the contrast medium. Moreover, we evaluated a possible relationship between the occurrence of CI-AKI and total hydration volume administered. There were no significant differences in baseline clinical, biochemical, and procedural characteristics in the 3 groups. Overall, CI-AKI occurred in 93 patients (20.6%): the incidence was significantly lower in the early hydration group (12%) with respect to both the late hydration group (22.7%) and the control group (27.3%) (P for trend=0.001). In hydrated patients (early and late hydration groups), lower infused volumes were associated with a significant increase in CI-AKI incidence, and the optimal cutoff point of hydration volume that best discriminates patients at higher risk was ≤960 mL. Adequate intravenous volume expansion may prevent CI-AKI in patients undergoing primary PCI. A regimen of preprocedure and postprocedure hydration therapy with sodium bicarbonate appears to be more efficacious than postprocedure hydration only with isotonic saline.

Seasonal hydroclimatic impacts of Brazilian sugar cane expansion

NASA Astrophysics Data System (ADS)

Georgescu, M.; Lobell, D. B.; Field, C. B.; Mahalov, A.

2012-12-01

Brazil is the leading producer of sugar cane in the world with roughly half used for ethanol production. Because of suitable climatic growing conditions, the majority of biofuel production is derived from sugar plantations in southeastern states. Anticipated increases in global demand for biofuels are expected to lead to future sugar cane expansion extending into Brazilian pasturelands and native cerrado. Prior to undergoing large-scale expansion an evaluation of impacts on the region's hydroclimate is warranted. Using a suite of multi-year ensemble-based simulations with the WRF modeling system, we quantify hydroclimatic consequences of sugar cane expansion across portions of south-central Brazil. Conversion from current land use to sugar cane causes opposing seasonal impacts on near-surface temperature. Proggresively greater cooling is simulated during the course of the growing season, followed by an abrupt warming shift post-harvest. Although seasonal impacts on near-surface temperature are significant, with cooling of 1C occurring during the peak of the growing season followed by warming of similar magnitude, impacts are small when annually averaged. Ensemble mean differences between the imposed sugar cane expansion and non-expansion scenario are suggestive of a drying precipitation trend, yet large uncertainty among individual members precludes definitive statements about impacts on the region's rainfall.

Mapping Brazilian Cropland Expansion, 2000-2013

NASA Astrophysics Data System (ADS)

Zalles, V.; Hansen, M.; Potapov, P.

2016-12-01

Brazil is one of the world's leading producers and exporters of agricultural goods. Despite undergoing significant increases in its cropland area in the last decades, it remains one of the countries with the most potential for further agricultural expansion. Most notably, the expansion in production areas of commodity crops such as soybean, corn, and sugarcane has become the leading cause of land cover conversion in Brazil. Natural land covers, such as the Amazon and Cerrado forests, have been negatively affected by this agricultural expansion, causing carbon emissions, biodiversity loss, altered water cycles, and many other disturbances to ecosystem services. Monitoring of change in cropland area extent can provide relevant information to decision makers seeking to understand and manage land cover change drivers and their impacts. In this study, the freely-available Landsat archive was leveraged to produce a large-scale, methodologically consistent map of cropland cover at 30 m. resolution for the entire Brazilian territory in the year 2000. Additionally, we mapped cropland expansion from 2000 to 2013, and used statistical sampling techniques to accurately estimate cropland area per Brazilian state. Using the Global Forest Change product produced by Hansen et al. (2013), we can disaggregate forest cover loss due to cropland expansion by year, revealing spatiotemporal trends that could advance our understanding of the drivers of forest loss.

The Curriculum of the College of Agriculture. Bulletin, 1920, No. 40

ERIC Educational Resources Information Center

Woodward, Carl R.

1921-01-01

The last two decades have seen a rapid expansion of State colleges of agriculture in the United States. The enrollment has increased rapidly and this has meant a rapid development in the means for offering resident instruction. The courses of study have been passing through a process of evolution coincident with this growth. In general it is…

Profound hearing loss associated with hydrocodone/acetaminophen abuse.

PubMed

Friedman, R A; House, J W; Luxford, W M; Gherini, S; Mills, D

2000-03-01

To describe profound hearing loss associated with hydrocodone overuse and the successful rehabilitation of these patients with cochlear implantation. Retrospective review. A tertiary otologic referral center. Twelve patients with rapidly progressive hearing loss and a concurrent history of hydrocodone overuse. Comprehensive medical histories, physical findings, audiometric tests, and, in those patients undergoing cochlear implantation, postimplantation performance data were reviewed. Clinical characteristics of hydrocodone-related hearing loss and open set word and sentence performance in those patients undergoing cochlear implantation. Hydrocodone overuse was associated with rapidly progressive sensorineural hearing loss in 12 patients. In four patients the initial presentation was unilateral, and two of the patients experienced vestibular symptoms. None of the 12 patients experienced improved thresholds after high-dose prednisone. Seven of the eight patients undergoing cochlear implantation have demonstrated early success with their devices. Hydrocodone is frequently prescribed in combination with acetaminophen for the relief of pain and has a side effects profile similar to other medications in its class. Although not described previously, overuse or abuse can be associated with a rapidly progressive sensorineural hearing loss. These patients can be successfully rehabilitated with cochlear implantation.

Recognition of Time-Compressed and Natural Speech with Selective Temporal Enhancements by Young and Elderly Listeners

ERIC Educational Resources Information Center

Gordon-Salant, Sandra; Fitzgibbons, Peter J.; Friedman, Sarah A.

2007-01-01

Purpose: The goal of this experiment was to determine whether selective slowing of speech segments improves recognition performance by young and elderly listeners. The hypotheses were (a) the benefits of time expansion occur for rapid speech but not for natural-rate speech, (b) selective time expansion of consonants produces greater score…

Foreign Universities in China: A Case Study

ERIC Educational Resources Information Center

Ennew, Christine T.; Fujia, Yang

2009-01-01

The international dimension of higher education has expanded rapidly in recent decades and private provision is becoming increasingly widespread in response to the diverse pressures of globalisation, rapid expansion in demand and increased pressures on public finances. As higher education has become marketised, opportunities for international…

Recent Insights into the Cell Biology of Thyroid Angiofollicular Units

PubMed Central

Denef, Jean-François; Lengelé, Benoit; Many, Marie-Christine; Gérard, Anne-Catherine

2013-01-01

In thyrocytes, cell polarity is of crucial importance for proper thyroid function. Many intrinsic mechanisms of self-regulation control how the key players involved in thyroid hormone (TH) biosynthesis interact in apical microvilli, so that hazardous biochemical processes may occur without detriment to the cell. In some pathological conditions, this enzymatic complex is disrupted, with some components abnormally activated into the cytoplasm, which can lead to further morphological and functional breakdown. When iodine intake is altered, autoregulatory mechanisms outside the thyrocytes are activated. They involve adjacent capillaries that, together with thyrocytes, form the angiofollicular units (AFUs) that can be considered as the functional and morphological units of the thyroid. In response to iodine shortage, a rapid expansion of the microvasculature occurs, which, in addition to nutrients and oxygen, optimizes iodide supply. These changes are triggered by angiogenic signals released from thyrocytes via a reactive oxygen species/hypoxia-inducible factor/vascular endothelial growth factor pathway. When intra- and extrathyrocyte autoregulation fails, other forms of adaptation arise, such as euthyroid goiters. From onset, goiters are morphologically and functionally heterogeneous due to the polyclonal nature of the cells, with nodules distributed around areas of quiescent AFUs containing globules of compact thyroglobulin (Tg) and surrounded by a hypotrophic microvasculature. Upon TSH stimulation, quiescent AFUs are activated with Tg globules undergoing fragmentation into soluble Tg, proteins involved in TH biosynthesis being expressed and the local microvascular network extending. Over time and depending on physiological needs, AFUs may undergo repetitive phases of high, moderate, or low cell and tissue activity, which may ultimately culminate in multinodular goiters. PMID:23349248

Facile Rearrangement of 3-Oxoalkyl Radicals is Evident in Low-Temperature Gas-Phase Oxidation of Ketones

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

Scheer, Adam M.; Welz, Oliver; Sasaki, Darryl Y.

The pulsed photolytic chlorine-initiated oxidation of methyl-tert-butyl ketone (MTbuK), di-tert-butyl ketone (DTbuK), and a series of partially deuterated diethyl ketones (DEK) is studied in the gas phase at 8 Torr and 550–650 K. Products are monitored as a function of reaction time, mass, and photoionization energy using multiplexed photoionization mass spectrometry with tunable synchrotron ionizing radiation. The results establish that the primary 3-oxoalkyl radicals of those ketones, formed by abstraction of a hydrogen atom from the carbon atom in γ-position relative to the carbonyl oxygen, undergo a rapid rearrangement resulting in an effective 1,2-acyl group migration, similar to that inmore » a Dowd–Beckwith ring expansion. Without this rearrangement, peroxy radicals derived from MTbuK and DTbuK cannot undergo HO2 elimination to yield a closed-shell unsaturated hydrocarbon coproduct. However, not only are these coproducts observed, but they represent the dominant oxidation channels of these ketones under the conditions of this study. For MTbuK and DTbuK, the rearrangement yields a more stable tertiary radical, which provides the thermodynamic driving force for this reaction. Even in the absence of such a driving force in the oxidation of partially deuterated DEK, the 1,2-acyl group migration is observed. Quantum chemical (CBS-QB3) calculations show the barrier for gas-phase rearrangement to be on the order of 10 kcal mol–1. The MTbuK oxidation experiments also show several minor channels, including β-scission of the initial radicals and cyclic ether formation.« less

Adiabatic expansion, early X-ray data and the central engine in GRBs

NASA Astrophysics Data System (ADS)

Barniol Duran, R.; Kumar, P.

2009-05-01

The Swift satellite early X-ray data show a very steep decay in most of the gamma-ray bursts light curves. This decay is either produced by the rapidly declining continuation of the central engine activity or by some leftover radiation starting right after the central engine shuts off. The latter scenario consists of the emission from an `ember' that cools via adiabatic expansion and, if the jet angle is larger than the inverse of the source Lorentz factor, the large angle emission. In this work, we calculate the temporal and spectral properties of the emission from such a cooling ember, providing a new treatment for the microphysics of the adiabatic expansion. We use the adiabatic invariance of p2⊥/B (p⊥ is the component of the electrons' momentum normal to the magnetic field, B) to calculate the electrons' Lorentz factor during the adiabatic expansion; the electron momentum becomes more and more aligned with the local magnetic field as the expansion develops. We compare the theoretical expectations of the adiabatic expansion (and the large angle emission) with the current observations of the early X-ray data and find that only ~20 per cent of our sample of 107 bursts are potentially consistent with this model. This leads us to believe that, for most bursts, the central engine does not turn off completely during the steep decay of the X-ray light curve; therefore, this phase is produced by the continued rapidly declining activity of the central engine.

Bilateral cross-bite treated by repeated rapid maxillary expansions: a 17-year follow-up case.

PubMed

Cozzani, M; Mazzotta, L; Caprioglio, A

2014-07-01

The objective of this paper is to show the clinical results after the repeated application of a Haas expander for rapid maxillary expansion (RME) anchored onto deciduous teeth in a 7-year-old patient that presented bilateral cross-bite, superior crowding and no space for permanent lateral incisors eruption. A first Haas expander was applied to the patient. She was told to activate it once a day, each activation was equal to 0.20 mm. After the first RME, the bilateral cross-bite was solved but still there was not enough space for lateral incisor eruption. A second and then a third Haas expander were applied, with the same activation protocol as the first one, in order to gain space in the anterior region and to achieve proper eruption of the lateral incisors. The patient was then treated with fixed appliances. At debonding the patient presented well aligned arch-forms: space for lateral incisor eruption was gained and superior crowding was solved. Bilateral cross-bite was also corrected. She was seen again 10 years and 17 years after expansions: she showed no relapse and presented a good functional occlusion that had remained stable, and an aesthetically pleasant smile, however she exhibited gingival recessions. Repeated rapid maxillary expansion, anchored onto deciduous teeth, performed in early mixed dentition represents a safe and successful treatment to correct severe bilateral cross- bites and to create space for maxillary incisor eruption.

Brillouin-Wigner theory for high-frequency expansion in periodically driven systems: Application to Floquet topological insulators

NASA Astrophysics Data System (ADS)

Mikami, Takahiro; Kitamura, Sota; Yasuda, Kenji; Tsuji, Naoto; Oka, Takashi; Aoki, Hideo

2016-04-01

We construct a systematic high-frequency expansion for periodically driven quantum systems based on the Brillouin-Wigner (BW) perturbation theory, which generates an effective Hamiltonian on the projected zero-photon subspace in the Floquet theory, reproducing the quasienergies and eigenstates of the original Floquet Hamiltonian up to desired order in 1 /ω , with ω being the frequency of the drive. The advantage of the BW method is that it is not only efficient in deriving higher-order terms, but even enables us to write down the whole infinite series expansion, as compared to the van Vleck degenerate perturbation theory. The expansion is also free from a spurious dependence on the driving phase, which has been an obstacle in the Floquet-Magnus expansion. We apply the BW expansion to various models of noninteracting electrons driven by circularly polarized light. As the amplitude of the light is increased, the system undergoes a series of Floquet topological-to-topological phase transitions, whose phase boundary in the high-frequency regime is well explained by the BW expansion. As the frequency is lowered, the high-frequency expansion breaks down at some point due to band touching with nonzero-photon sectors, where we find numerically even more intricate and richer Floquet topological phases spring out. We have then analyzed, with the Floquet dynamical mean-field theory, the effects of electron-electron interaction and energy dissipation. We have specifically revealed that phase transitions from Floquet-topological to Mott insulators emerge, where the phase boundaries can again be captured with the high-frequency expansion.

Skeletal and dental changes following surgically assisted rapid palatal expansion.

PubMed

Byloff, Friedrich K; Mossaz, Claude F

2004-08-01

The purpose of this study was to analyse the changes produced by surgically assisted rapid palatal expansion (SARPE) longitudinally on 14 patients aged between 18 and 41 years. A pre-fabricated Hyrax appliance was cemented prior to the surgical intervention, which consisted of a maxillary buccal corticotomy with pterygoid separation. Models and postero-anterior (PA) headfilms were taken before expansion (T1), at the end of expansion (T2), at the end of retention (T3) and at least 1 year post-surgery (T4). Overall expansion and relapse were measured directly on the casts. Transverse distances increased more at the first molars (8.7 mm) and premolars (8.1 and 8.3 mm) than in the canine (5.2 mm) and second molar (5.5 mm) region. Minimal relapse occurred during the retention phase. The arch width decreased more during the post-retention period, with more pronounced reduction at the teeth used as anchorage during the expansion procedure (-2.0 mm for the first premolars and -2.6 mm for the first molars). The mean total dental relapse was 28 per cent. PA radiographic analysis for angular changes showed 9.6 degrees of lateral tipping per side during expansion. One-third of this movement relapsed during the retention period (-3.3 degrees) and this trend (-6.0 degrees) continued during the post-retention phase to reach practically the original value at T1. Skeletal changes monitored on the PA headfilms were minimal with great individual variation. The mean expansion measured in the proximity of the osteotomy site was only 1.3 mm. From this amount, 0.4 mm was lost during the retention and post-retention periods. Based on these findings, it appears that maxillary skeletal expansion by SARPE is mainly a lateral rotation of the two maxillary halves with only minimal horizontal translation.

Assessment of vertical changes during maxillary expansion using quad helix or bonded rapid maxillary expander.

PubMed

Conroy-Piskai, Cara; Galang-Boquiren, Maria Therese S; Obrez, Ales; Viana, Maria Grace Costa; Oppermann, Nelson; Sanchez, Flavio; Edgren, Bradford; Kusnoto, Budi

2016-11-01

To determine if there is a significantly different effect on vertical changes during phase I palatal expansion treatment using a quad helix and a bonded rapid maxillary expander in growing skeletal Class I and Class II patients. This retrospective study looked at 2 treatment groups, a quad helix group and a bonded rapid maxillary expander group, before treatment (T1) and at the completion of phase I treatment (T2). Each treatment group was compared to an untreated predicted growth model. Lateral cephalograms at T1 and T2 were traced and analyzed for changes in vertical dimension. No differences were found between the treatment groups at T1, but significant differences at T2 were found for convexity, lower facial height, total facial height, facial axis, and Frankfort Mandibular Plane Angle (FMA) variables. A comparison of treatment groups at T2 to their respective untreated predicted growth models found a significant difference for the lower facial height variable in the quad helix group and for the upper first molar to palatal plane (U6-PP) variable in the bonded expander group. Overall, both the quad helix expander and the bonded rapid maxillary expander showed minimal vertical changes during palatal expansion treatment. The differences at T2 suggested that the quad helix expander had more control over skeletal vertical measurements. When comparing treatment results to untreated predicted growth values, the quad helix expander appeared to better maintain lower facial height and the bonded rapid maxillary expander appeared to better maintain the maxillary first molar vertical height.

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

Bronskill, M.J.

The spatial distribution of radioactivity in the injection site, and its rate of clearance, have been measured in patients undergoing various types of interstitial radiocolloid lymphoscintigraphy using 99mTc-antimony sulfide colloid. The clearance of radioactivity from the injection site, and the expansion with time of the localized radioactivity vary considerably for different sites of injection. Maximum absorbed dose estimates of 45.6 rads to the center of the injection site (rectus sheath) and 21 rads to individual lymph nodes have been calculated for patients undergoing internal mammary lymphoscintigraphy with 450 mu Ci injected radioactivity. Absorbed dose estimates for finger web, toe web,more » and perianal injection sites are also presented.« less

Early evolution of an energetic coronal mass ejection and its relation to EUV waves

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

Liu, Rui; Wang, Yuming; Shen, Chenglong, E-mail: rliu@ustc.edu.cn

2014-12-10

We study a coronal mass ejection (CME) associated with an X-class flare whose initiation is clearly observed in the low corona with high-cadence, high-resolution EUV images, providing us a rare opportunity to witness the early evolution of an energetic CME in detail. The eruption starts with a slow expansion of cool overlying loops (∼1 MK) following a jet-like event in the periphery of the active region. Underneath the expanding loop system, a reverse S-shaped dimming is seen immediately above the brightening active region in hot EUV passbands. The dimming is associated with a rising diffuse arch (∼6 MK), which wemore » interpret as a preexistent, high-lying flux rope. This is followed by the arising of a double hot channel (∼10 MK) from the core of the active region. The higher structures rise earlier and faster than lower ones, with the leading front undergoing extremely rapid acceleration up to 35 km s{sup –2}. This suggests that the torus instability is the major eruption mechanism and that it is the high-lying flux rope rather than the hot channels that drives the eruption. The compression of coronal plasmas skirting and overlying the expanding loop system, whose aspect ratio h/r increases with time as a result of the rapid upward acceleration, plays a significant role in driving an outward-propagating global EUV wave and a sunward-propagating local EUV wave, respectively.« less

Burr hole drainage for complicated spontaneous intracranial hypotension syndrome.

PubMed

Liu, Yu-Fang; Lin, Hung-Lin; Cho, Der-Yang; Chen, Chun-Chung; Lo, Yu-Chien; Chiou, Shang-Ming

2008-09-01

Spontaneous intracranial hypotension is a potentially severe condition that is caused by continuous cerebrospinal fluid leakage. Clinically, most patients have a benign course and the condition remits after conservative management. We report two consecutive patients who presented with acute expansion of subdural collection and disturbed consciousness. Both patients recovered completely after undergoing burr hole drainage.

Rapid Population Growth and Rural Community Change: A Focus on Land Use Issues.

ERIC Educational Resources Information Center

Garkovich, Lorraine

Land use controls are often a major point of conflict between recent migrants and long-term residents of rapidly growing communities. Such conflict was noted in a case study of a rural community undergoing rapid population growth. The revision of a comprehensive land use plan for the community provided the opportunity to evaluate citizen…

Hidden asymmetry and long range rapidity correlations

NASA Astrophysics Data System (ADS)

Bialas, A.; Bzdak, A.; Zalewski, K.

2012-04-01

Interpretation of long-range rapidity correlations in terms of the fluctuating rapidity density distribution of the system created in high-energy collisions is proposed. When applied to recent data of the STAR Collaboration, it shows a substantial asymmetric component in the shape of this system in central Au-Au collisions, implying that boost invariance is violated on the event-by-event basis even at central rapidity. This effect may seriously influence the hydrodynamic expansion of the system.

Reprobing the mechanism of negative thermal expansion in siliceous faujasite

DOE PAGES

Attfield, Martin P.; Feygenson, Mikhail; Neuefeind, Joerg C.; ...

2016-02-11

A combination of Rietveld refinement and PDF analysis of total neutron scattering data are used to provide further insight into the negative thermal expansion mechanism of siliceous faujasite. The negative thermal expansion mechanism of siliceous faujasite is attributed to the transverse vibrations of bridging oxygen atoms resulting in the coupled librations of the SiO 4 tetrahedra. The constituent SiO 4 tetrahedra are revealed to expand in size with temperature which is a behaviour that has not been determined directly previously and they are also shown to undergo some distortion as temperature is increased. However, these distortions are not distinct enoughmore » in any geometric manner for the average behaviour of the SiO 4 tetrahedra not to be considered as that of a rigid units. The work further displays the benefits of using total scattering experiments to unveil the finer details of dynamic thermomechanical processes within crystalline materials.« less

Self-renewal of a purified Tie2+ hematopoietic stem cell population relies on mitochondrial clearance.

PubMed

Ito, Kyoko; Turcotte, Raphaël; Cui, Jinhua; Zimmerman, Samuel E; Pinho, Sandra; Mizoguchi, Toshihide; Arai, Fumio; Runnels, Judith M; Alt, Clemens; Teruya-Feldstein, Julie; Mar, Jessica C; Singh, Rajat; Suda, Toshio; Lin, Charles P; Frenette, Paul S; Ito, Keisuke

2016-12-02

A single hematopoietic stem cell (HSC) is capable of reconstituting hematopoiesis and maintaining homeostasis by balancing self-renewal and cell differentiation. The mechanisms of HSC division balance, however, are not yet defined. Here we demonstrate, by characterizing at the single-cell level a purified and minimally heterogeneous murine Tie2 + HSC population, that these top hierarchical HSCs preferentially undergo symmetric divisions. The induction of mitophagy, a quality control process in mitochondria, plays an essential role in self-renewing expansion of Tie2 + HSCs. Activation of the PPAR (peroxisome proliferator-activated receptor)-fatty acid oxidation pathway promotes expansion of Tie2 + HSCs through enhanced Parkin recruitment in mitochondria. These metabolic pathways are conserved in human TIE2 + HSCs. Our data thus identify mitophagy as a key mechanism of HSC expansion and suggest potential methods of cell-fate manipulation through metabolic pathways. Copyright © 2016, American Association for the Advancement of Science.

Self-renewal of a purified Tie2+ hematopoietic stem cell population relies on mitochondrial clearance

PubMed Central

Ito, Kyoko; Turcotte, Raphaël; Cui, Jinhua; Zimmerman, Samuel E.; Pinho, Sandra; Mizoguchi, Toshihide; Arai, Fumio; Runnels, Judith M.; Alt, Clemens; Teruya-Feldstein, Julie; Mar, Jessica C.; Singh, Rajat; Suda, Toshio; Lin, Charles P.; Frenette, Paul S.; Ito, Keisuke

2016-01-01

A single hematopoietic stem cell (HSC) is capable of reconstituting hematopoiesis and maintaining homeostasis by balancing self-renewal and cell differentiation. The mechanisms of HSC division balance, however, are not yet defined. Here we demonstrate, by characterizing at the single-cell level a purified and minimally heterogeneous murine Tie2+ HSC population, that these top hierarchical HSCs preferentially undergo symmetric divisions. The induction of mitophagy, a quality control process in mitochondria, plays an essential role in self-renewing expansion of Tie2+ HSCs. Activation of the PPAR (peroxisome proliferator–activated receptor)–fatty acid oxidation pathway promotes expansion of Tie2+ HSCs through enhanced Parkin recruitment in mitochondria. These metabolic pathways are conserved in human TIE2+ HSCs. Our data thus identify mitophagy as a key mechanism of HSC expansion and suggest potential methods of cell-fate manipulation through metabolic pathways. PMID:27738012

Glacial Lake Expansion in the Central Himalayas by Landsat Images, 1990–2010

PubMed Central

Nie, Yong; Liu, Qiao; Liu, Shiyin

2013-01-01

Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed. PMID:24376778

Analysis of the dentoalveolar effects of slow and rapid maxillary expansion in complete bilateral cleft lip and palate patients: a randomized clinical trial.

PubMed

de Medeiros Alves, Arthur César; Garib, Daniela Gamba; Janson, Guilherme; de Almeida, Araci Malagodi; Calil, Louise Resti

2016-09-01

The purpose of this study was to compare the dentoalveolar effects of slow (SME) and rapid (RME) maxillary expansions in patients with complete bilateral cleft lip and palate (BCLP). A sample of 50 patients with BCLP and maxillary arch constriction was randomly and equally allocated into two groups. Group SME comprised patients (mean age of 8.8 years) treated with quad-helix appliance. Group RME comprised individuals (mean age of 8.9 years) treated with Hyrax expander. Digital dental models obtained immediately pre-expansion (T1) and 6 months after the active expansion period (T2) were used for measuring maxillary dental arch widths, arch perimeter, arch length, palatal depth, buccolingual inclination of posterior teeth and differential amount of expansion accomplished at the canine and molar regions. Inter-phase and intergroup comparisons were performed using paired t tests and t tests, respectively (p < 0.05). SME and RME caused significant increase of arch widths and arch perimeter. Arch length and palatal depth decreased nonsignificantly with SME but significantly with RME. Buccal tooth inclination was significant only for maxillary deciduous canines in both groups. The quad-helix appliance showed a significant differential expansion between anterior and posterior regions. No differences were observed between SME and RME for all variables. Differences were not found between the dentoalveolar effects of SME and RME in patients with BCLP. SME demanded a greater therapy time compared to RME. Both expansion procedures can be similarly indicated to correct maxillary arch constriction in patients with BCLP in the mixed dentition.

Glacial lake expansion in the central Himalayas by Landsat images, 1990-2010.

PubMed

Nie, Yong; Liu, Qiao; Liu, Shiyin

2013-01-01

Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed.

Glacial Lake Expansion in the Central Himalayas By Landsat Images, 1990-2010

NASA Astrophysics Data System (ADS)

Nie, Y.; Liu, Q.; Liu, S.

2014-12-01

Glacial lake outburst flood (GLOF) is a serious hazard in high, mountainous regions. In the Himalayas, catastrophic risks of GLOFs have increased in recent years because most Himalayan glaciers have experienced remarkable downwasting under a warming climate. However, current knowledge about the distribution and recent changes in glacial lakes within the central Himalaya mountain range is still limited. Here, we conducted a systematic investigation of the glacial lakes within the entire central Himalaya range by using an object-oriented image processing method based on the Landsat Thematic Mapper (TM) or Enhanced Thematic Mapper (ETM) images from 1990 to 2010. We extracted the lake boundaries for four time points (1990, 2000, 2005 and 2010) and used a time series inspection method combined with a consistent spatial resolution of Landsat images that consistently revealed lake expansion. Our results show that the glacial lakes expanded rapidly by 17.11% from 1990 to 2010. The pre-existing, larger glacial lakes, rather than the newly formed lakes, contributed most to the areal expansion. The greatest expansions occurred at the altitudinal zones between 4800 m and 5600 m at the north side of the main Himalayan range and between 4500 m and 5600 m at the south side, respectively. Based on the expansion rate, area and type of glacial lakes, we identified 67 rapidly expanding glacial lakes in the central Himalayan region that need to be closely monitored in the future. The warming and increasing amounts of light-absorbing constituents of snow and ice could have accelerated the melting that directly affected the glacial lake expansion. Across the main central Himalayas, glacial lakes at the north side show more remarkable expansion than those at the south side. An effective monitoring and warning system for critical glacial lakes is urgently needed.

Expansion of Vocational Education in Neoliberal China: Hope and Despair among Rural Youth

ERIC Educational Resources Information Center

Koo, Anita

2016-01-01

The rise of China as the world factory in the last few decades has been accompanied by a rapid expansion in vocational education. A growing number of youth from rural backgrounds now have the chance to receive post-compulsory education in vocational training schools. Using human capital theory as an analytical focus, this study examines their…

Some Reflections on the Expansion and Quality of Higher Education in Public Universities in Kenya

ERIC Educational Resources Information Center

Sifuna, Daniel N.

2010-01-01

This article explores the socio-economic and political factors which have contributed to the rapid expansion of education in the public universities in Kenya and how it has impacted on the quality of education in these institutions. It mainly focuses on the response to insatiable public demands for university education in the country as well as…

Rapid Expansion of Higher Education in Turkey: The Challenges of Recently Established Public Universities (2006-2013)

ERIC Educational Resources Information Center

Özoglu, Murat; Gür, Bekir S.; Gümüs, Sedat

2016-01-01

Like many other countries around the world, Turkey has faced several challenges in expanding higher education (HE) opportunities to masses. Trying to meet the ever-growing demand for HE, Turkey has implemented a bold expansion plan by establishing 51 public universities (PUs) after 2006, mostly in less-developed regions of the country. This study…

Ribosomal DNA copy number amplification and loss in human cancers is linked to tumor genetic context, nucleolus activity, and proliferation

PubMed Central

2017-01-01

Ribosomal RNAs (rRNAs) are transcribed from two multicopy DNA arrays: the 5S ribosomal DNA (rDNA) array residing in a single human autosome and the 45S rDNA array residing in five human autosomes. The arrays are among the most variable segments of the genome, exhibit concerted copy number variation (cCNV), encode essential components of the ribosome, and modulate global gene expression. Here we combined whole genome data from >700 tumors and paired normal tissues to provide a portrait of rDNA variation in human tissues and cancers of diverse mutational signatures, including stomach and lung adenocarcinomas, ovarian cancers, and others of the TCGA panel. We show that cancers undergo coupled 5S rDNA array expansion and 45S rDNA loss that is accompanied by increased estimates of proliferation rate and nucleolar activity. These somatic changes in rDNA CN occur in a background of over 10-fold naturally occurring rDNA CN variation across individuals and cCNV of 5S-45S arrays in some but not all tissues. Analysis of genetic context revealed associations between cancer rDNA CN amplification or loss and the presence of specific somatic alterations, including somatic SNPs and copy number gain/losses in protein coding genes across the cancer genome. For instance, somatic inactivation of the tumor suppressor gene TP53 emerged with a strong association with coupled 5S expansion / 45S loss in several cancers. Our results uncover frequent and contrasting changes in the 5S and 45S rDNA along rapidly proliferating cell lineages with high nucleolar activity. We suggest that 5S rDNA amplification facilitates increased proliferation, nucleolar activity, and ribosomal synthesis in cancer, whereas 45S rDNA loss emerges as a byproduct of transcription-replication conflict in rapidly replicating tumor cells. The observations raise the prospects of using the rDNA arrays as re-emerging targets for the design of novel strategies in cancer therapy. PMID:28880866

Development of a Mental Health Nursing Simulation: Challenges and Solutions

ERIC Educational Resources Information Center

Kidd, Lori I.; Morgan, Karyn I.; Savery, John R.

2012-01-01

Nursing education programs are proliferating rapidly in the United States in an effort to meet demand for nurse professionals. Multiple challenges arise from this rapid expansion. One challenge is finding sufficient clinical sites to accommodate students. Increased competition for scarce resources requires creativity in clinical contracting. This…

Rapid gas development in the Fayetteville shale basin, Arkansas

EPA Science Inventory

Advances in drilling and extraction of natural gas have resulted in rapid expansion of wells in shale basins. The rate of gas well installation in the Fayetteville shale is 774 wells a year since 2005 with thousands more planned. The Fayetteville shale covers 23,000 km2 although ...

Two Decades of Negative Thermal Expansion Research: Where Do We Stand?

PubMed Central

Lind, Cora

2012-01-01

Negative thermal expansion (NTE) materials have become a rapidly growing area of research over the past two decades. The initial discovery of materials displaying NTE over a large temperature range, combined with elucidation of the mechanism behind this unusual property, was followed by predictions that these materials will find use in various applications through controlled thermal expansion composites. While some patents have been filed and devices built, a number of obstacles have prevented the widespread implementation of NTE materials to date. This paper reviews NTE materials that contract due to transverse atomic vibrations, their potential for use in controlled thermal expansion composites, and known problems that could interfere with such applications. PMID:28817027

The role of citzens in detecting and responding to a rapid marine invasion

USGS Publications Warehouse

Scyphers, Stephen B.; Powers, Sean P.; Akins, J. Lad; Drymon, J. Marcus; Martin, Charles M.; Schobernd, Zeb H.; Schofield, Pamela J.; Shipp, Robert L.; Switzer, Theodore S.

2015-01-01

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1–2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in 2011 (+367%). From the survey of spearfishers, we determined that diving experience and personal observations of lionfish strongly influenced perceived impacts, and these perceptions were powerful predictors of support for initiatives. Our study demonstrates the value of engaging citizens for assessing and responding to large-scale and time-sensitive conservation problems.

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

Fincke, J.R.; Swank, W.D.; Haggard, D.C.

This paper describes the experimental demonstration of a process for the direct plasma reduction of depleted uranium hexafluoride to uranium metal. The process exploits the large departures from equilibrium that can be achieved in the rapid supersonic expansion of a totally dissociated and partially ionized mixture of UF{sub 6}, Ar, He, and H{sub 2}. The process is based on the rapid condensation of subcooled uranium vapor and the relatively slow rate of back reaction between metallic uranium and HF to F{sub 2} to reform stable fluorides. The high translational velocities and rapid cooling result in an overpopulation of atomic hydrogenmore » which persists throughout the expansion process. Atomic hydrogen shifts the equilibrium composition by inhibiting the reformation of uranium-fluorine compounds. This process has the potential to reduce the cost of reducing UF{sub 6} to uranium metal with the added benefit of being a virtually waste free process. The dry HF produced is a commodity which has industrial value.« less

Oscillating flow and heat transfer in a channel with sudden cross section change

NASA Technical Reports Server (NTRS)

Ibrahim, Mounir; Hashim, Waqar

1993-01-01

We have computationally examined oscillating flow (zero mean) between two parallel plates with a sudden change in cross section. The flow was assumed to be laminar incompressible with the inflow velocity uniform over the channel cross section but varying sinusoidally with time. The cases studied cover wide ranges of Re(sub max) (from 187.5 to 2000), Va (from 1 to 10.66), the expansion ratio (1:2 and 1:4) and A(sub r) (2 and 4). Also, three different geometric cases were discussed: (1) asymmetric expansion/contraction; (2) symmetric expansion/contraction; and (3) symmetric blunt body. For these oscillating flow conditions, the fluid undergoes sudden expansion in one-half of the cycle and sudden contraction inthe other half. The instantaneous friction factor, for some ranges of Re(sub max) and Va, deviated substantially from the steady-state friction factor for the same flow parameters. A region has been identified below which the flow is laminar quasi-steady. A videotape showing computer simulations of the oscillating flow demonstrates the usefulness of the current analyses in providing information on the transient hydraulic phenomena.

The rapid expansion of (mainstream) health psychology in France: Historical foundations.

PubMed

Santiago-Delefosse, Marie; Del Rio Carral, Maria

2018-03-01

This article traces the historical evolution of ongoing theoretical debates in psychology in France from the 1940s until today. Its aim is to show how the conjunction of certain conditions led to a rapid expansion of American-derived mainstream health psychology during the 1980s. The authors describe the French context in the post-World War II period and outline the implementation of 'clinical psychology in health settings' in the 1950s, under the influence of Daniel Lagache. The strong critiques of the new psychology profession in the 1950s, 1960s and 1970s are examined. Our conclusion reflects upon future implications of ongoing rivalries between different approaches to psychology.

The Formation and Early Evolution of a CME and the Associated Shock on 2014 January 8

NASA Astrophysics Data System (ADS)

Wan, Linfeng; Cheng, Xin; Shi, Tong; Su, Wei; Ding, Mingde

2017-08-01

We study the formation and early evolution of a limb coronal mass ejection (CME) and its associated shock wave that occurred on 2014 January 8. The extreme ultraviolet (EUV) images provided by AIA on board \\textit{Solar Dynamics Observatory} disclose that the CME first appears as a bubble-like structure. Subsequently, its expansion forms the CME and causes a quasi-circular EUV wave. Both the CME and the wave front are clearly visible at all of the AIA EUV passbands. Through a detailed kinematical analysis, it is found that the expansion of the CME undergoes two phases: a first phase with a strong but transient lateral over-expansion followed by a second phase with a self-similar expansion. The temporal evolution of the expansion velocity coincides very well with the variation of the 25--50 keV hard X-ray (HXR) flux of the associated flare, which indicates that magnetic reconnection most likely plays an important role in driving the expansion. Moreover, we find that, when the velocity of the CME reaches $\\sim$600 km s$^{-1}$, the EUV wave starts to evolve into a shock wave, which is evidenced by the appearance of a type II radio burst. Interestingly, we also notice an unusual solar radio signal at $\\sim$4 GHz that is similar to the pattern of a type II radio burst but drifts to higher frequencies at a rate of $\\sim$0.3 MHz per second during about 7 minutes. Its derived density is $\\sim$5$\\times$10$^{10}$ cm$^{-3}$ and increases slowly with time. Joint imaging observations of HXR and EUV help to locate the loop-top region and calculate its thermal proprieties, including slowly increasing densities ($\\sim$5$\\times$10$^{10}$ cm$^{-3}$) and temperatures ($\\sim$14 MK). The similar results obtained from two different ways above imply the possibility of this scenario: plasma blobs that are ejected along the current sheet via magnetic reconnection collide with underlying flare loops that are undergoing chromospheric evaporation. Finally, we also study the thermal properties of the CME and the EUV wave. We find that the plasma in the CME leading front and the wave front has a temperature of $\\sim$2 MK, while that in the CME core region and the flare region has a much higher temperature of $\\ge$8 MK.

Chromosomal aberrations and deoxyribonucleic acid single-strand breaks in adipose-derived stem cells during long-term expansion in vitro.

PubMed

Froelich, Katrin; Mickler, Johannes; Steusloff, Gudrun; Technau, Antje; Ramos Tirado, Mario; Scherzed, Agmal; Hackenberg, Stephan; Radeloff, Andreas; Hagen, Rudolf; Kleinsasser, Norbert

2013-07-01

Adipose-derived stem cells (ASCs) are a promising mesenchymal cell source for tissue engineering approaches. To obtain an adequate cell amount, in vitro expansion of the cells may be required in some cases. To monitor potential contraindications for therapeutic applications in humans, DNA strand breaks and chromosomal aberrations in ASCs during in vitro expansion were examined. After isolation of ASC from human lipoaspirates of seven patients, in vitro expansion over 10 passages was performed. Cells from passages 1, 2, 3, 5 and 10 were used for the alkaline single-cell microgel electrophoresis (comet) assay to detect DNA single-strand breaks and alkali labile as well as incomplete excision repair sites. Chromosomal changes were examined by means of the chromosomal aberration test. During in vitro expansion, ASC showed no DNA single-strand breaks in the comet assay. With the chromosomal aberration test, however, a significant increase in chromosomal aberrations were detected. The study showed that although no DNA fragmentation could be determined, the safety of ASC cannot be ensured with respect to chromosome stability during in vitro expansion. Thus, reliable analyses for detecting ASC populations, which accumulate chromosomal aberrations or even undergo malignant transformation during extensive in vitro expansion, must be implemented as part of the safety evaluation of these cells for stem cell-based therapy. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Deterministic absorbed dose estimation in computed tomography using a discrete ordinates method

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

Norris, Edward T.; Liu, Xin, E-mail: xinliu@mst.edu; Hsieh, Jiang

Purpose: Organ dose estimation for a patient undergoing computed tomography (CT) scanning is very important. Although Monte Carlo methods are considered gold-standard in patient dose estimation, the computation time required is formidable for routine clinical calculations. Here, the authors instigate a deterministic method for estimating an absorbed dose more efficiently. Methods: Compared with current Monte Carlo methods, a more efficient approach to estimating the absorbed dose is to solve the linear Boltzmann equation numerically. In this study, an axial CT scan was modeled with a software package, Denovo, which solved the linear Boltzmann equation using the discrete ordinates method. Themore » CT scanning configuration included 16 x-ray source positions, beam collimators, flat filters, and bowtie filters. The phantom was the standard 32 cm CT dose index (CTDI) phantom. Four different Denovo simulations were performed with different simulation parameters, including the number of quadrature sets and the order of Legendre polynomial expansions. A Monte Carlo simulation was also performed for benchmarking the Denovo simulations. A quantitative comparison was made of the simulation results obtained by the Denovo and the Monte Carlo methods. Results: The difference in the simulation results of the discrete ordinates method and those of the Monte Carlo methods was found to be small, with a root-mean-square difference of around 2.4%. It was found that the discrete ordinates method, with a higher order of Legendre polynomial expansions, underestimated the absorbed dose near the center of the phantom (i.e., low dose region). Simulations of the quadrature set 8 and the first order of the Legendre polynomial expansions proved to be the most efficient computation method in the authors’ study. The single-thread computation time of the deterministic simulation of the quadrature set 8 and the first order of the Legendre polynomial expansions was 21 min on a personal computer. Conclusions: The simulation results showed that the deterministic method can be effectively used to estimate the absorbed dose in a CTDI phantom. The accuracy of the discrete ordinates method was close to that of a Monte Carlo simulation, and the primary benefit of the discrete ordinates method lies in its rapid computation speed. It is expected that further optimization of this method in routine clinical CT dose estimation will improve its accuracy and speed.« less

Moment expansion for ionospheric range error

NASA Technical Reports Server (NTRS)

Mallinckrodt, A.; Reich, R.; Parker, H.; Berbert, J.

1972-01-01

On a plane earth, the ionospheric or tropospheric range error depends only on the total refractivity content or zeroth moment of the refracting layer and the elevation angle. On a spherical earth, however, the dependence is more complex; so for more accurate results it has been necessary to resort to complex ray-tracing calculations. A simple, high-accuracy alternative to the ray-tracing calculation is presented. By appropriate expansion of the angular dependence in the ray-tracing integral in a power series in height, an expression is obtained for the range error in terms of a simple function of elevation angle, E, at the expansion height and of the mth moment of the refractivity, N, distribution about the expansion height. The rapidity of convergence is heavily dependent on the choice of expansion height. For expansion heights in the neighborhood of the centroid of the layer (300-490 km), the expansion to N = 2 (three terms) gives results accurate to about 0.4% at E = 10 deg. As an analytic tool, the expansion affords some insight on the influence of layer shape on range errors in special problems.

Asymmetric rapid maxillary expansion in true unilateral crossbite malocclusion: a prospective controlled clinical study.

PubMed

Ileri, Zehra; Basciftci, Faruk Ayhan

2015-03-01

To investigate the short-term effects of the asymmetric rapid maxillary (ARME) appliance on the vertical, sagittal, and transverse planes in patients with true unilateral posterior crossbite. Subjects were divided into two groups. The treatment group was comprised of 21 patients with unilateral posterior crossbite (mean age  =  13.3 ± 2.1 years). Members of this group were treated with the ARME appliance. The control group was comprised of 17 patients with Angle Class I who were kept under observation (mean age  =  12.3 ± 0.8 years). Lateral and frontal cephalograms were taken before the expansion (T1), immediately after expansion (T2), and at postexpansion retention (T3) in the treatment group and at preobservation (T1) and postobservation (T2) in the control group. A total of 34 measurements were assessed on cephalograms. For statistical analysis, the Wilcoxon test and analysis of covariance were used. The ARME appliance produced significant increases in nasal, maxillary base, upper arch, and lower arch dimensions (P < .01) and a clockwise rotation of the occlusal plane (P  =  .001). The ARME appliance created asymmetric increments in the transversal dimensions of the nose, maxilla, and upper arch in the short term. Asymmetric expansion therapy for subjects with unilateral maxillary deficiency may provide satisfactory outcomes in adolescents, with the exception of mandibular arch expansion. The triangular pattern of expansion caused clockwise rotation of the mandible and the occlusal plane and produced significant alterations in the vertical facial dimensions, whereas it created no displacement in maxilla in the sagittal plane.

Emergency Department Expansion Versus Patient Flow Improvement: Impact on Patient Experience of Care.

PubMed

Sayah, Assaad; Lai-Becker, Melisa; Kingsley-Rocker, Lisa; Scott-Long, Tasha; O'Connor, Kelly; Lobon, Luis F

2016-02-01

Most strategies used to help improve the patient experience of care and ease emergency department (ED) crowding and diversion require additional space and personnel resources, major process improvement interventions, or a combination of both. To compare the impact of ED expansion vs. patient flow improvement and the establishment of a rapid assessment unit (RAU) on the patient experience of care in a medium-size safety net ED. This paper describes a study of a single ED wherein the department first undertook a physical expansion (2006 Q2 to 2007 Q2) followed by a reorganization of patient flow and establishment of an RAU (2009 Q2) by the use of an interrupted time series analysis. In the time period after ED expansion, significant negative trends were observed: decreasing Press Ganey percentiles (-4.1 percentile per quarter), increasing door-to-provider time (+4.9 minutes per quarter), increasing duration of stay (+13.2 minutes per quarter), and increasing percent of patients leaving without being seen (+0.11 per quarter). After the RAU was established, significant immediate impacts were observed for door-to-provider time (-25.8 minutes) and total duration of stay (-66.8 minutes). The trends for these indicators further suggested the improvements continued to be significant over time. Furthermore, the negative trends for the Press Ganey outcomes observed after ED expansion were significantly reversed and in the positive direction after the RAU. Our results demonstrate that the impact of process improvement and rapid assessment implementation is far greater than the impact of renovation and facility expansion. Copyright © 2016 Elsevier Inc. All rights reserved.

Urban expansion dynamics and natural habitat loss in China: a multiscale landscape perspective.

PubMed

He, Chunyang; Liu, Zhifeng; Tian, Jie; Ma, Qun

2014-09-01

China's extensive urbanization has resulted in a massive loss of natural habitat, which is threatening the nation's biodiversity and socioeconomic sustainability. A timely and accurate understanding of natural habitat loss caused by urban expansion will allow more informed and effective measures to be taken for the conservation of biodiversity. However, the impact of urban expansion on natural habitats is not well-understood, primarily due to the lack of accurate spatial information regarding urban expansion across China. In this study, we proposed an approach that can be used to accurately summarize the dynamics of urban expansion in China over two recent decades (1992-2012), by integrating data on nighttime light levels, a vegetation index, and land surface temperature. The natural habitat loss during the time period was evaluated at the national, ecoregional, and local scales. The results revealed that China had experienced extremely rapid urban growth from 1992 to 2012 with an average annual growth rate of 8.74%, in contrast with the global average of 3.20%. The massive urban expansion has resulted in significant natural habitat loss in some areas in China. Special attention needs to be paid to the Pearl River Delta, where 25.79% or 1518 km(2) of the natural habitat and 41.99% or 760 km(2) of the local wetlands were lost during 1992-2012. This raises serious concerns about species viability and biodiversity. Effective policies and regulations must be implemented and enforced to sustain regional and national development in the context of rapid urbanization. © 2014 John Wiley & Sons Ltd.

Intraspecific competition favours niche width expansion in Drosophila melanogaster.

PubMed

Bolnick, D I

2001-03-22

Ecologists have proposed that when interspecific competition is reduced, competition within a species becomes a potent evolutionary force leading to rapid diversification. This view reflects the observation that populations invading species-poor communities frequently evolve broader niches. Niche expansion can be associated with an increase in phenotypic variance (known as character release), with the evolution of polymorphisms, or with divergence into many species using distinct resources (adaptive radiation). The relationship between intraspecific competition and diversification is known from theory, and has been used as the foundation for some models of speciation. However, there has been little empirical proof that niches evolve in response to intraspecific competition. To test this hypothesis, I introduced cadmium-intolerant Drosophila melanogaster populations to environments containing both cadmium-free and cadmium-laced resources. Here I show that populations experiencing high competition adapted to cadmium more rapidly than low competition populations. This provides experimental confirmation that competition in a population can drive niche expansion onto new resources for which competition is less severe.

Space-time asymptotics of the two dimensional Navier-Stokes flow in the whole plane

NASA Astrophysics Data System (ADS)

Okabe, Takahiro

2018-01-01

We consider the space-time behavior of the two dimensional Navier-Stokes flow. Introducing some qualitative structure of initial data, we succeed to derive the first order asymptotic expansion of the Navier-Stokes flow without moment condition on initial data in L1 (R2) ∩ Lσ2 (R2). Moreover, we characterize the necessary and sufficient condition for the rapid energy decay ‖ u (t) ‖ 2 = o (t-1) as t → ∞ motivated by Miyakawa-Schonbek [21]. By weighted estimated in Hardy spaces, we discuss the possibility of the second order asymptotic expansion of the Navier-Stokes flow assuming the first order moment condition on initial data. Moreover, observing that the Navier-Stokes flow u (t) lies in the Hardy space H1 (R2) for t > 0, we consider the asymptotic expansions in terms of Hardy-norm. Finally we consider the rapid time decay ‖ u (t) ‖ 2 = o (t - 3/2 ) as t → ∞ with cyclic symmetry introduced by Brandolese [2].

CT analysis of nasal volume changes after surgically-assisted rapid maxillary expansion.

PubMed

Tausche, Eve; Deeb, Wayel; Hansen, Lars; Hietschold, Volker; Harzer, Winfried; Schneider, Matthias

2009-07-01

Aim of this study was to detect the changes in nasal volume due to bone-borne, surgically-assisted rapid palatal expansion (RPE) with the Dresden Distractor using computed tomography (CT). 17 patients (mean age 28.8) underwent axial CT scanning before and 6 months after RPE. The nasal bone width was examined in the coronal plane. Cross-sectional images of the nasal cavity were taken of the area surrounding the piriform aperture, choanae and in between. Bony nasal volume was computed by connecting the three cross-sectional areas. All but two patients showed a 4.8% increase in nasal volume (SD 4.6%). The highest value, 33.3% (SD 45.1%), was measured anteriorly at the level of the nasal floor. This correlated with the midpalatal suture's V-shaped opening. There was no significant correlation between an increase in nasal volume and transverse dental arch expansion. As most of the air we breathe passes the lower nasal floor, an improvement in nasal breathing is likely.

Protecting tropical forests from the rapid expansion of rubber using carbon payments.

PubMed

Warren-Thomas, Eleanor M; Edwards, David P; Bebber, Daniel P; Chhang, Phourin; Diment, Alex N; Evans, Tom D; Lambrick, Frances H; Maxwell, James F; Nut, Menghor; O'Kelly, Hannah J; Theilade, Ida; Dolman, Paul M

2018-03-02

Expansion of Hevea brasiliensis rubber plantations is a resurgent driver of deforestation, carbon emissions, and biodiversity loss in Southeast Asia. Southeast Asian rubber extent is massive, equivalent to 67% of oil palm, with rapid further expansion predicted. Results-based carbon finance could dis-incentivise forest conversion to rubber, but efficacy will be limited unless payments match, or at least approach, the costs of avoided deforestation. These include opportunity costs (timber and rubber profits), plus carbon finance scheme setup (transaction) and implementation costs. Using comprehensive Cambodian forest data, exploring scenarios of selective logging and conversion, and assuming land-use choice is based on net present value, we find that carbon prices of $30-$51 per tCO 2 are needed to break even against costs, higher than those currently paid on carbon markets or through carbon funds. To defend forests from rubber, either carbon prices must be increased, or other strategies are needed, such as corporate zero-deforestation pledges, and governmental regulation and enforcement of forest protection.

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

Yu, Cun; Ren, Yang; Cui, Lishan

Under high pressure, materials usually shrink during compression as described by an equation of state. Here, we present the anomalous volume expansion behavior of a one-dimensional Nb nanowire embedded in a NiTi transforming matrix, while the matrix undergoes a pressure-induced martensitic transformation. The Nb volume expansion depends on the NiTi transition pressure range from the matrix, which is controlled by the shear strain induced by different pressure transmitting media. The transformation-induced interfacial stresses between Nb and NiTi may play a major role in this anomaly. In conclusion, our discovery sheds new light on the nano-interfacial effect on mechanical anomalies inmore » heterogeneous systems during a pressure-induced phase transition.« less

A Missing-link in the Supernova-GRB Connection: The Case of SN 2012ap

NASA Astrophysics Data System (ADS)

Chakraborti, Sayan; Soderberg, Alicia; Chomiuk, Laura; Kamble, Atish; Yadav, Naveen; Ray, Alak; Hurley, Kevin; Margutti, Raffaella; Milisavljevic, Dan; Bietenholz, Michael; Brunthaler, Andreas; Pignata, Giuliano; Pian, Elena; Mazzali, Paolo; Fransson, Claes; Bartel, Norbert; Hamuy, Mario; Levesque, Emily; MacFadyen, Andrew; Dittmann, Jason; Krauss, Miriam; Briggs, M. S.; Connaughton, V.; Yamaoka, K.; Takahashi, T.; Ohno, M.; Fukazawa, Y.; Tashiro, M.; Terada, Y.; Murakami, T.; Goldsten, J.; Barthelmy, S.; Gehrels, N.; Cummings, J.; Krimm, H.; Palmer, D.; Golenetskii, S.; Aptekar, R.; Frederiks, D.; Svinkin, D.; Cline, T.; Mitrofanov, I. G.; Golovin, D.; Litvak, M. L.; Sanin, A. B.; Boynton, W.; Fellows, C.; Harshman, K.; Enos, H.; von Kienlin, A.; Rau, A.; Zhang, X.; Savchenko, V.

2015-06-01

Gamma-ray bursts (GRBs) are characterized by ultra-relativistic outflows, while supernovae are generally characterized by non-relativistic ejecta. GRB afterglows decelerate rapidly, usually within days, because their low-mass ejecta rapidly sweep up a comparatively larger mass of circumstellar material. However, supernovae with heavy ejecta can be in nearly free expansion for centuries. Supernovae were thought to have non-relativistic outflows except for a few relativistic ones accompanied by GRBs. This clear division was blurred by SN 2009bb, the first supernova with a relativistic outflow without an observed GRB. However, the ejecta from SN 2009bb was baryon loaded and in nearly free expansion for a year, unlike GRBs. We report the first supernova discovered without a GRB but with rapidly decelerating mildly relativistic ejecta, SN 2012ap. We discovered a bright and rapidly evolving radio counterpart driven by the circumstellar interaction of the relativistic ejecta. However, we did not find any coincident GRB with an isotropic fluence of more than one-sixth of the fluence from GRB 980425. This shows for the first time that central engines in SNe Ic, even without an observed GRB, can produce both relativistic and rapidly decelerating outflows like GRBs.

The Rapidity Density Distributions and Longitudinal Expansion Dynamics of Identified Pions from the STAR Beam Energy Scan

NASA Astrophysics Data System (ADS)

Flores, Christopher E.

2016-12-01

The Beam Energy Scan (BES) at the Relativistic Heavy-Ion Collider was proposed to characterize the properties of the medium produced in heavy-ion interactions over a broad range of baryon chemical potential. The aptitude of the STAR detector for mid-rapidity measurements has previously been leveraged to measure identified particle yields and spectra to extract bulk properties for the BES energies for | y | ≤ 0.1. However, to extract information on expansion dynamics and full phase space particle production, it is necessary to study identified particle rapidity density distributions. We present the first rapidity density distributions of identified pions from Au+Au collisions at √{sNN} = 7.7 , 11.5, and 19.6 GeV from the BES program as measured by the STAR detector. We use these distributions to obtain the full phase space yields of the pions to provide additional information of the system's chemistry. Further, we report the width of the rapidity density distributions compared to the width expected from Landau hydrodynamics. Finally, we interpret the results as a function of collision energy and discuss them in the context of previous energy scans done at the AGS and SPS.

CD98 at the crossroads of adaptive immunity and cancer

PubMed Central

Cantor, Joseph M.; Ginsberg, Mark H.

2012-01-01

Adaptive immunity, a vertebrate specialization, adds memory and exquisite specificity to the basic innate immune responses present in invertebrates while conserving metabolic resources. In adaptive immunity, antigenic challenge requires extremely rapid proliferation of rare antigen-specific lymphocytes to produce large, clonally expanded effector populations that neutralize pathogens. Rapid proliferation and resulting clonal expansion are dependent on CD98, a protein whose well-conserved orthologs appear restricted to vertebrates. Thus, CD98 supports lymphocyte clonal expansion to enable protective adaptive immunity, an advantage that could account for the presence of CD98 in vertebrates. CD98 supports lymphocyte clonal expansion by amplifying integrin signals that enable proliferation and prevent apoptosis. These integrin-dependent signals can also provoke cancer development and invasion, anchorage-independence and the rapid proliferation of tumor cells. CD98 is highly expressed in many cancers and contributes to formation of tumors in experimental models. Strikingly, vertebrates, which possess highly conserved CD98 proteins, CD98-binding integrins and adaptive immunity, also display propensity towards invasive and metastatic tumors. In this Commentary, we review the roles of CD98 in lymphocyte biology and cancer. We suggest that the CD98 amplification of integrin signaling in adaptive immunity provides survival benefits to vertebrates, which, in turn, bear the price of increased susceptibility to cancer. PMID:22499670

Diversification of the phaseoloid legumes: effects of climate change, range expansion and habit shift

PubMed Central

Li, Honglei; Wang, Wei; Lin, Li; Zhu, Xiangyun; Li, Jianhua; Zhu, Xinyu; Chen, Zhiduan

2013-01-01

Understanding which factors have driven the evolutionary success of a group is a fundamental question in biology. Angiosperms are the most successful group in plants and have radiated and adapted to various habitats. Among angiosperms, legumes are a good example for such successful radiation and adaptation. We here investigated how the interplay of past climate changes, geographical expansion and habit shifts has promoted diversification of the phaseoloid legumes, one of the largest clades in the Leguminosae. Using a comprehensive genus-level phylogeny from three plastid markers, we estimate divergence times, infer habit shifts, test the phylogenetic and temporal diversification heterogeneity, and reconstruct ancestral biogeographical ranges. We found that the phaseoloid lineages underwent twice dramatic accumulation. During the Late Oligocene, at least six woody clades rapidly diverged, perhaps in response to the Late Oligocene warming and aridity, and a result of rapidly exploiting new ecological opportunities in Asia, Africa and Australia. The most speciose lineage is herbaceous and began to rapidly diversify since the Early Miocene, which was likely ascribed to arid climates, along with the expansion of seasonally dry tropical forests in Africa, Asia, and America. The phaseoloid group provides an excellent case supporting the idea that the interplay of ecological opportunities and key innovations drives the evolutionary success. PMID:24130564

Rapid Range Expansion Is Not Restricted by Inbreeding in a Sexually Cannibalistic Spider

PubMed Central

Zimmer, Stefanie M.; Krehenwinkel, Henrik; Schneider, Jutta M.

2014-01-01

Few studies investigated whether rapid range expansion is associated with an individual's short-term fitness costs due to an increased risk of inbred mating at the front of expansion. In mating systems with low male mating rates both sexes share potential inbreeding costs and general mechanisms to avoid or reduce these costs are expected. The spider Argiope bruennichi expanded its range recently and we asked whether rapid settlement of new sites exposes individuals to a risk of inbreeding. We sampled four geographically separated subpopulations, genotyped individuals, arranged matings and monitored hatching success. Hatching success was lowest in egg-sacs derived from sibling pairs and highest in egg-sacs derived from among-population crosses, while within-population crosses were intermediate. This indicates that inbreeding might affect hatching success in the wild. Unlike expected, differential hatching success of within- and among-population crosses did not correlate with genetic distance of mating pairs. In contrast, we found high genetic diversity based on 16 microsatellite markers and a fragment of the mitochondrial COI gene in all populations. Our results suggest that even a very recent settlement secures the presence of genetically different mating partners. This leads to costs of inbreeding since the population is not inbred. PMID:24759976

Diversification of the phaseoloid legumes: effects of climate change, range expansion and habit shift.

PubMed

Li, Honglei; Wang, Wei; Lin, Li; Zhu, Xiangyun; Li, Jianhua; Zhu, Xinyu; Chen, Zhiduan

2013-01-01

Understanding which factors have driven the evolutionary success of a group is a fundamental question in biology. Angiosperms are the most successful group in plants and have radiated and adapted to various habitats. Among angiosperms, legumes are a good example for such successful radiation and adaptation. We here investigated how the interplay of past climate changes, geographical expansion and habit shifts has promoted diversification of the phaseoloid legumes, one of the largest clades in the Leguminosae. Using a comprehensive genus-level phylogeny from three plastid markers, we estimate divergence times, infer habit shifts, test the phylogenetic and temporal diversification heterogeneity, and reconstruct ancestral biogeographical ranges. We found that the phaseoloid lineages underwent twice dramatic accumulation. During the Late Oligocene, at least six woody clades rapidly diverged, perhaps in response to the Late Oligocene warming and aridity, and a result of rapidly exploiting new ecological opportunities in Asia, Africa and Australia. The most speciose lineage is herbaceous and began to rapidly diversify since the Early Miocene, which was likely ascribed to arid climates, along with the expansion of seasonally dry tropical forests in Africa, Asia, and America. The phaseoloid group provides an excellent case supporting the idea that the interplay of ecological opportunities and key innovations drives the evolutionary success.

Spectral Analysis of Word-Initial Alveolar and Velar Plosives Produced by Iranian Children with Cleft Lip and Palate

ERIC Educational Resources Information Center

Eshghi, Marziye; Zajac, David J.; Bijankhan, Mahmood; Shirazi, Mohsen

2013-01-01

Spectral moment analysis (SMA) was used to describe voiceless alveolar and velar stop-plosive production in Persian-speaking children with repaired cleft lip and palate (CLP). Participants included 11 children with bilateral CLP who were undergoing maxillary expansion and 20 children without any type of orofacial clefts. Four of the children with…

Emergent Cultural Change: Unintended Consequences of a Strategic Information Technology Services Implementation in a United Kingdom University

ERIC Educational Resources Information Center

Waring, Teresa; Skoumpopoulou, Dimitra

2013-01-01

Over the past 20 years, universities in the United Kingdom have been undergoing a dramatic period of transformation and change which can be attributed to the expansion of the higher education sector, the growth in student numbers and the development of an ideological approach to public service management referred to as "new…

TGF-β converts apoptotic stimuli into the signal for Th9 differentiation

PubMed Central

Takami, Mariko; Love, Robert B.; Iwashima, Makio

2012-01-01

Naturally arising CD4+CD25+FoxP3+ regulatory T cells (nTregs) play an essential role in maintenance of immune homeostasis and peripheral tolerance. Previously, we reported that conventional CD4+ and CD8+ T cells undergo p53-induced CD28-dependent apoptosis (PICA) when stimulated with a combination of immobilized anti-CD3 and anti-CD28 antibodies while nTregs expand robustly under the same conditions, suggesting that there is a differential survival mechanism against PICA between conventional T cells and nTregs. Here, we demonstrate that TGF-β signaling is required for nTregs to survive PICA. Conversely, when an active form of exogenous TGF-β is present, conventional T cells become resistant to PICA and undergo robust expansion instead of apoptosis, with reduction of the pro-apoptotic protein Bim and FoxO3a. A substantial fraction of PICA-resisted T cells expressed IL-9 (TH9 cells). Moreover, the presence of IL-6 along with TGF-β led to generation of TH17 cells from conventional T cells. Together, the data demonstrate a novel role for TGF-β in the homeostasis of Tregs and effector T cell differentiation/ expansion. PMID:22461692

Determination of the Specific Heat Ratio of a Gas in a Plastic Syringe

ERIC Educational Resources Information Center

Chamberlain, Jeff

2010-01-01

The rapid compression or expansion of a gas in a plastic syringe is a poor approximation of an adiabatic process. Heat exchange with the walls of the syringe brings the gas to equilibrium in an amount of time that is not significantly greater than the length of the compression or expansion itself. Despite this limitation, it is still possible to…

"We Were Beet Workers, and that Was All": Beet Field Laborers in the North Platte Valley, 1902-1930

ERIC Educational Resources Information Center

Kipp, Dustin

2011-01-01

The experiences of the men, women, and children who labored in the beet fields of the North Platte Valley changed significantly as the sugar beet industry went through a period of rapid expansion prior to 1920 and then reached a relatively stable plateau. During the period of expansion, laborers were attracted by promises of reasonable wages, good…

Identifying the "Subnormal" Child in an Age of Expansion of Special Education and Child Science in the Netherlands (c.1945-1965)

ERIC Educational Resources Information Center

Bakker, Nelleke

2015-01-01

Between c.1945 and 1965 across the West special education has grown and differentiated substantially. In the Netherlands this expansion ran parallel to the academic recognition and rapid development of the study of learning disabilities. How are these two processes related? This article argues that in this country child science and special…

Genetic characterization and phylogeography of the wild boar Sus scrofa introduced into Uruguay

PubMed Central

García, Graciela; Vergara, Julia; Lombardi, Raúl

2011-01-01

The European wild boar Sus scrofa was first introduced into Uruguay, in southern South America during the early decades of the last century. Subsequently, and starting from founder populations, its range spread throughout the country and into the neighbouring Brazilian state Rio Grande do Sul. Due to the subsequent negative impact, it was officially declared a national pest. The main aim in the present study was to provide a more comprehensive scenario of wild boar differentiation in Uruguay, by using mtDNA markers to access the genetic characterization of populations at present undergoing rapid expansion. A high level of haplotype diversity, intermediate levels of nucleotide diversity and considerable population differentiation, were detected among sampled localities throughout major watercourses and catchment dams countrywide. Phylogenetic analysis revealed the existence of two different phylogroups, thereby reflecting two deliberate introduction events forming distantly genetic lineages in local wild boar populations. Our analysis lends support to the hypothesis that the invasive potential of populations emerge from introgressive hybridization with domestic pigs. On taking into account the appreciable differentiation and reduced migration between locales in wild boar populations, management strategies could be effective if each population were to be considered as a single management unit. PMID:21734838

Resilience of Alaska's Boreal Forest to Climatic Change

NASA Technical Reports Server (NTRS)

Chapin, F. S., III; McGuire, A. D.; Ruess, R. W.; Hollingsworth, T. N.; Mack, M. C.; Johnstone, J. F.; Kasischke, E. S.; Euskirchen, E. S.; Jones, J. B.; Jorgenson, M. T.;

Isolation of circulating tumor cells using photoacoustic flowmetry and two phase flow

NASA Astrophysics Data System (ADS)

O'Brien, Christine M.; Rood, Kyle D.; Gupta, Sagar K.; Mosley, Jeffrey D.; Goldschmidt, Benjamin S.; Sharma, Nikhilesh; Sengupta, Shramik; Viator, John A.

2011-03-01

Melanoma is the deadliest form of skin cancer, yet current diagnostic methods are inadequately sensitive. Patients must wait until secondary tumors form before malignancy can be diagnosed and treatment prescribed. Detection of cells that have broken off the original tumor and flow through the blood or lymph system can provide data for diagnosing and monitoring cancer. Our group utilizes the photoacoustic effect to detect metastatic melanoma cells, which contain the pigmented granule melanin. As a rapid laser pulse irradiates melanoma, the melanin undergoes thermo-elastic expansion and ultimately creates a photoacoustic wave. Thus, melanoma patient's blood samples can be enriched, leaving the melanoma in a white blood cell (WBC) suspension. Irradiated melanoma cells produce photoacoustic waves, which are detected with a piezoelectric transducer, while the optically transparent WBCs create no signals. Here we report an isolation scheme utilizing two-phase flow to separate detected melanoma from the suspension. By introducing two immiscible fluids through a t-junction into one flow path, the analytes are compartmentalized. Therefore, the slug in which the melanoma cell is located can be identified and extracted from the system. Two-phase immiscible flow is a label free technique, and could be used for other types of pathological analytes.

The ideal laboratory information system.

PubMed

Sepulveda, Jorge L; Young, Donald S

2013-08-01

Laboratory information systems (LIS) are critical components of the operation of clinical laboratories. However, the functionalities of LIS have lagged significantly behind the capacities of current hardware and software technologies, while the complexity of the information produced by clinical laboratories has been increasing over time and will soon undergo rapid expansion with the use of new, high-throughput and high-dimensionality laboratory tests. In the broadest sense, LIS are essential to manage the flow of information between health care providers, patients, and laboratories and should be designed to optimize not only laboratory operations but also personalized clinical care. To list suggestions for designing LIS with the goal of optimizing the operation of clinical laboratories while improving clinical care by intelligent management of laboratory information. Literature review, interviews with laboratory users, and personal experience and opinion. Laboratory information systems can improve laboratory operations and improve patient care. Specific suggestions for improving the function of LIS are listed under the following sections: (1) Information Security, (2) Test Ordering, (3) Specimen Collection, Accessioning, and Processing, (4) Analytic Phase, (5) Result Entry and Validation, (6) Result Reporting, (7) Notification Management, (8) Data Mining and Cross-sectional Reports, (9) Method Validation, (10) Quality Management, (11) Administrative and Financial Issues, and (12) Other Operational Issues.

Reliability over time of EEG-based mental workload evaluation during Air Traffic Management (ATM) tasks.

PubMed

Arico, Pietro; Borghini, Gianluca; Di Flumeri, Gianluca; Colosimo, Alfredo; Graziani, Ilenia; Imbert, Jean-Paul; Granger, Geraud; Benhacene, Railene; Terenzi, Michela; Pozzi, Simone; Babiloni, Fabio

2015-08-01

Machine-learning approaches for mental workload (MW) estimation by using the user brain activity went through a rapid expansion in the last decades. In fact, these techniques allow now to measure the MW with a high time resolution (e.g. few seconds). Despite such advancements, one of the outstanding problems of these techniques regards their ability to maintain a high reliability over time (e.g. high accuracy of classification even across consecutive days) without performing any recalibration procedure. Such characteristic will be highly desirable in real world applications, in which human operators could use such approach without undergo a daily training of the device. In this work, we reported that if a simple classifier is calibrated by using a low number of brain spectral features, between those ones strictly related to the MW (i.e. Frontal and Occipital Theta and Parietal Alpha rhythms), those features will make the classifier performance stable over time. In other words, the discrimination accuracy achieved by the classifier will not degrade significantly across different days (i.e. until one week). The methodology has been tested on twelve Air Traffic Controls (ATCOs) trainees while performing different Air Traffic Management (ATM) scenarios under three different difficulty levels.

Resilience of Alaska’s boreal forest to climatic change

USGS Publications Warehouse

Chapin, F.S.; McGuire, A. David; Ruess, Roger W.; Hollingsworth, Teresa N.; Mack, M.C.; Johnstone, J.F.; Kasischke, E.S.; Euskirchen, E.S.; Jones, J.B.; Jorgenson, M.T.; Kielland, K.; Kofinas, G.; Turetsky, M.R.; Yarie, J.; Lloyd, A.H.; Taylor, D.L.

2010-01-01

This paper assesses the resilience of Alaska’s boreal forest system to rapid climatic change. Recent warming is associated with reduced growth of dominant tree species, plant disease and insect outbreaks, warming and thawing of permafrost, drying of lakes, increased wildfire extent, increased postfire recruitment of deciduous trees, and reduced safety of hunters traveling on river ice. These changes have modified key structural features, feedbacks, and interactions in the boreal forest, including reduced effects of upland permafrost on regional hydrology, expansion of boreal forest into tundra, and amplification of climate warming because of reduced albedo (shorter winter season) and carbon release from wildfires. Other temperature-sensitive processes for which no trends have been detected include composition of plant and microbial communities, long-term landscape-scale change in carbon stocks, stream discharge, mammalian population dynamics, and river access and subsistence opportunities for rural indigenous communities. Projections of continued warming suggest that Alaska’s boreal forest will undergo significant functional and structural changes within the next few decades that are unprecedented in the last 6000 years. The impact of these social–ecological changes will depend in part on the extent of landscape reorganization between uplands and lowlands and on policies regulating subsistence opportunities for rural communities.

Health challenges in Kazakhstan and Central Asia.

PubMed

Adambekov, Shalkar; Kaiyrlykyzy, Aiym; Igissinov, Nurbek; Linkov, Faina

2016-01-01

The Central Asian region, which encompasses Kazakhstan, Uzbekistan, Tajikistan, Turkmenistan and Kyrgyzstan, is an interesting geographic region with a rich history dating back to the Silk Road, Mongol conquests and expansion of the Russian Empire. However, from a public health viewpoint, the Central Asian region is under-investigated, and many public health challenges exist, as countries of Central Asia inherited the centralised medical systems practiced in the Soviet Union, and are currently undergoing rapid transitions. A large number of low and middle-income countries around the world, including countries of Central Asia, face a double burden of chronic and infectious disease. This essay focuses on the exploration of the most important public health challenges in the Central Asian region, including limited scientific productivity, the double burden of chronic and infectious disease, the need for healthcare reform and the reduction in care variation. Central Asia has a large number of medical schools, medical centres, and emerging research institutes that can be used to foster a change in medical and public health practice in the region. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Differential Effects of Small Molecule WNT Agonists on the Multilineage Differentiation Capacity of Human Mesenchymal Stem Cells.

PubMed

Narcisi, Roberto; Arikan, Ozan H; Lehmann, Johannes; Ten Berge, Derk; van Osch, Gerjo J V M

2016-11-01

Human bone marrow-derived mesenchymal stem cells (MSCs) are promising candidates for cell-based therapies, but loss of expansion and differentiation potential in vitro limits their applicability. Recently we showed that WNT3A protein promoted MSC proliferation and enhanced their chondrogenic potential, while simultaneously suppressing the propensity of the cartilage to undergo hypertrophic maturation. Since WNT3A protein is costly and rapidly loses its activity in culture, we investigated the possibility of replacing it with cheaper commercially available WNT agonists, specifically lithium chloride (LiCl), CHIR99021 (CHIR), SKL2001, and AMBMP. Of these, we found that only CHIR and LiCl stimulated MSC proliferation. Moreover, CHIR enhanced the chondrogenic capacity of MSCs, whereas LiCl predominantly increased the osteo- and adipogenic capacity. The different WNT agonists also differentially impacted the surface marker profile of the MSCs, possibly explaining the observed differences. Moreover, CHIR suppressed the hypertrophic propensity of the MSC-derived cartilage after in vivo implantation to an extent approaching that of WNT3A protein. These results indicate that CHIR may be a promising alternative for WNT3A protein for certain applications of human bone marrow-derived MSCs.

Distinguished quantum states in a class of cosmological spacetimes and their Hadamard property

NASA Astrophysics Data System (ADS)

Dappiaggi, Claudio; Moretti, Valter; Pinamonti, Nicola

2009-06-01

In a recent paper, we proved that a large class of spacetimes, not necessarily homogeneous or isotropous and relevant at a cosmological level, possesses a preferred codimension 1 submanifold, i.e., the past cosmological horizon, on which it is possible to encode the information of a scalar field theory living in the bulk. Such bulk-to-boundary reconstruction procedure entails the identification of a preferred quasifree algebraic state for the bulk theory, enjoying remarkable properties concerning invariance under isometries (if any) of the bulk and energy positivity and reducing to well-known vacua in standard situations. In this paper, specializing to open Friedmann-Robertson-Walker models, we extend previously obtained results and we prove that the preferred state is of Hadamard form, hence the backreaction on the metric is finite and the state can be used as a starting point for renormalization procedures. Such state could play a distinguished role in the discussion of the evolution of scalar fluctuations of the metric, an analysis often performed in the development of any model describing the dynamic of an early Universe which undergoes an inflationary phase of rapid expansion in the past.

Grasping the health horizon: toward a virtual, interoperable platform of health innovations.

PubMed

Dawe, Marcus; Dugdale, Paul; Mcgann, Mathew

2015-01-01

The emergence of digital health, wearables, apps, telehealth and the proliferation of health services online are all indications that health is undergoing rapid innovation. Health innovation however has been traditionally slow, high cost and the commercialisation journey was not a guaranteed path to adoption outside the setting where it was developed whether in a hospital, university, clinic or lab. Most significant with this new explosion of health innovations is the sheer volume. The startup revolution, mobile health, personalised heath and globalisation of knowledge means that consumers are demanding innovations and are pulling health innovations through commercialisation with new modes of funding such as crowdsourcing and direct vendor purchases. Our Australian team initiated a project to use machine learning, data mining and classification techniques to bring together and analyse this expansion of heath innovations from all over the world. Following two years of data aggregation and quality analysis we present our findings which are applied to over 200,000 innovations from more than 25,000 organisations. Our findings have identified the dynamics and basis for a marketplace for health innovations that could assist innovators, health practitioners, consumers, investors and other health participants to research, evaluate and promote these innovations.

Stress modeling in colloidal dispersions undergoing non-viscometric flows

NASA Astrophysics Data System (ADS)

Dolata, Benjamin; Zia, Roseanna

2017-11-01

We present a theoretical study of the stress tensor for a colloidal dispersion undergoing non-viscometric flow. In such flows, the non-homogeneous suspension stress depends on not only the local average total stresslet-the sum of symmetric first moments of both the hydrodynamic traction and the interparticle force-but also on the average quadrupole, octupole, and higher-order moments. To compute the average moments, we formulate a six dimensional Smoluchowski equation governing the microstructural evolution of a suspension in an arbitrary fluid velocity field. Under the conditions of rheologically slow flow, where the Brownian relaxation of the particles is much faster than the spatiotemporal evolution of the flow, the Smoluchowski equation permits asymptotic solution, revealing a suspension stress that follows a second-order fluid constitutive model. We obtain a reciprocal theorem and utilize it to show that all constitutive parameters of the second-order fluid model may be obtained from two simpler linear-response problems: a suspension undergoing simple shear and a suspension undergoing isotropic expansion. The consequences of relaxing the assumption of rheologically slow flow, including the appearance of memory and microcontinuum behaviors, are discussed.

Stereoscopy in Static Scientific Imagery in an Informal Education Setting: Does It Matter?

ERIC Educational Resources Information Center

Price, C. Aaron; Lee, H.-S.; Malatesta, K.

2014-01-01

Stereoscopic technology (3D) is rapidly becoming ubiquitous across research, entertainment and informal educational settings. Children of today may grow up never knowing a time when movies, television and video games were not available stereoscopically. Despite this rapid expansion, the field's understanding of the impact of stereoscopic…

Fast Quasi-Adiabatic Gas Cooling: An Experiment Revisited

ERIC Educational Resources Information Center

Oss, S.; Gratton, L. M.; Calza, G.; Lopez-Arias, T.

2012-01-01

The well-known experiment of the rapid expansion and cooling of the air contained in a bottle is performed with a rapidly responsive, yet very cheap thermometer. The adiabatic, low temperature limit is approached quite closely and measured with our apparatus. A straightforward theoretical model for this process is also presented and discussed.…

Undergraduate Chemistry Education in Chinese Universities: Addressing the Challenges of Rapid Growth

ERIC Educational Resources Information Center

Gou, Xiaojun; Cao, Haishi

2010-01-01

In the past 30 years, university-level chemistry education in China has been experiencing significant changes because of the rapid expansion of its university education system. These changes are reflected in improvements to the existing education goals, classroom teaching methods, textbooks, teaching facilities, teacher profiles, lab activities,…

Accompanying coordinate expansion and recurrence relation method using a transfer relation scheme for electron repulsion integrals with high angular momenta and long contractions

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

Hayami, Masao; Seino, Junji; Nakai, Hiromi, E-mail: nakai@waseda.jp

An efficient algorithm for the rapid evaluation of electron repulsion integrals is proposed. The present method, denoted by accompanying coordinate expansion and transferred recurrence relation (ACE-TRR), is constructed using a transfer relation scheme based on the accompanying coordinate expansion and recurrence relation method. Furthermore, the ACE-TRR algorithm is extended for the general-contraction basis sets. Numerical assessments clarify the efficiency of the ACE-TRR method for the systems including heavy elements, whose orbitals have long contractions and high angular momenta, such as f- and g-orbitals.

Thermal Properties and Structural Stability of LaCoO3 in Reducing and Oxidizing Environments

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

Radovic, Miladin; Speakman, Scott A; Allard Jr, Lawrence Frederick

2008-09-01

Thermal expansion of LaCoO3 perovskite in air and 4% H2/96% Ar reducing atmosphere has been studied by Thermal Mechanical Analysis (TMA). The thermal behavior of LaCoO3 in air exhibits a non-linear expansion in 100 400 C temperature range. A significant increase of CTE measured in air both during heating and cooling experiments occurs in the 200 250 C temperature range, corresponding to a known spin state transition. LaCoO3 is found to be unstable in a reducing atmosphere. It undergoes a series of expansion and contractions due to phase transformations beginning around 500 C with very intensive chemical/phase changes at 850oCmore » and above. These expansions and contractions are directly related to the formation of La3Co3O8, La2CoO4, La4Co3O10, La2O3, CoO, and other Co compounds due to the reducing atmosphere. Although LaCoO3 is a good ionic and electronic conductor and catalyst, its high thermal expansion as well structural instability in reducing environments presents a serious restriction for its application in solid oxide fuel cells, sensors or gas separation membranes.« less

Delayed blastulation, multinucleation, and expansion grade are independently associated with live-birth rates in frozen blastocyst transfer cycles.

PubMed

Desai, Nina; Ploskonka, Stephanie; Goodman, Linnea; Attaran, Marjan; Goldberg, Jeffrey M; Austin, Cynthia; Falcone, Tommaso

2016-11-01

To identify blastocyst features independently predictive of successful pregnancy and live births with vitrified-warmed blastocysts. Retrospective study. Academic hospital. Women undergoing a cycle with transfer of blastocysts vitrified using the Rapid-i closed carrier (n = 358). None. Clinical pregnancy and live-birth rates analyzed using logistic regression analysis. A total of 669 vitrified-warmed blastocysts were assessed. The survival rate was 95%. A mean of 1.7 ± 0.5 embryos were transferred. The clinical pregnancy, live-birth, and implantation rates were 55%, 46%, and 43%, respectively. The odds of clinical pregnancy (odds ratio [OR] 3.08; 95% confidence interval [CI], 1.88-5.12) and live birth (OR 2.93; 95% CI, 1.79-4.85) were three times higher with day-5 blastocysts versus slower-growing day-6 vitrified blastocysts, irrespective of patient age at cryopreservation. Blastocysts from multinucleated embryos were half as likely to result in a live birth (OR 0.46; 95% CI, 0.22-0.91). A four -fold increase in live birth was observed if an expanded blastocyst was available for transfer. The inner cell mass-trophectoderm score correlated to positive outcomes in the univariate analysis. The implantation rate was statistically significantly higher for day-5 versus day-6 vitrified blastocysts (50% vs. 29%, respectively). The blastocyst expansion grade after warming was predictive of successful outcomes independent of the inner cell mass or trophectoderm score. Delayed blastulation and multinucleation were independently associated with lower live-birth rates in frozen cycles. Implantation potential of the frozen blastocysts available should be included in the decision-making process regarding embryo number for transfer. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Building operative care capacity in a resource limited setting: The Mongolian model of the expansion of sustainable laparoscopic cholecystectomy.

PubMed

Wells, Katie M; Lee, Yu-Jin; Erdene, Sandag; Erdene, Sarnai; Sanchin, Urjin; Sergelen, Orgoi; Zhang, Chong; Rodriguez, Brandon P; deVries, Catherine R; Price, Raymond R

2016-08-01

The benefits of laparoscopic cholecystectomy, including rapid recovery and fewer infections, have been largely unavailable to the majority of people in developing countries. Compared to other countries, Mongolia has an extremely high incidence of gallbladder disease. In 2005, only 2% of cholecystectomies were performed laparoscopically. This is a retrospective review of the transition from open to laparoscopic cholecystectomy throughout Mongolia. A cross-sectional, retrospective review was conducted of demographic patient data, diagnosis type, and operation performed (laparoscopic versus open cholecystectomy) from 2005-2013. Trends were analyzed from 6 of the 21 provinces (aimags) throughout Mongolia, and data were culled from 7 regional diagnostic referral and treatment centers and 2 tertiary academic medical centers. The data were analyzed by individual training center and by year before being compared between rural and urban centers. We analyzed and compared 14,522 cholecystectomies (n = 4,086 [28%] men, n = 10,436 [72%] women). Men and women were similar in age (men 52.2, standard deviation 14.8; women 49.4, standard deviation 15.7) and in the percentage undergoing laparoscopic cholecystectomy (men 39%, women 42%). By 2013, 58% of gallbladders were removed laparoscopically countrywide compared with only 2% in 2005. In 2011, laparoscopic cholecystectomy surpassed open cholecystectomy as the primary method for gallbladder removal countrywide. More than 315 Mongolian health care practitioners received laparoscopic training in 19 of the country's 21 aimags (states). By 2013, 58% of cholecystectomies countrywide were performed laparoscopically, a dramatic increase over 9 years. The expansion of laparoscopic cholecystectomy has transformed the care of biliary tract disease in Mongolia despite the country's limited resources. Copyright © 2016 Elsevier Inc. All rights reserved.

Canine Platelet Lysate Is Inferior to Fetal Bovine Serum for the Isolation and Propagation of Canine Adipose Tissue- and Bone Marrow-Derived Mesenchymal Stromal Cells

PubMed Central

Russell, Keith A.; Gibson, Thomas W. G.; Chong, Andrew; Co, Carmon; Koch, Thomas G.

2015-01-01

Background Mesenchymal stromal cells (MSC) are increasingly investigated for their clinical utility in dogs. Fetal bovine serum (FBS) is a common culture supplement used for canine MSC expansion. However, FBS content is variable, its clinical use carries risk of an immune response, and its cost is increasing due to global demand. Platelet lysate (PL) has proven to be a suitable alternative to FBS for expansion of human MSC. Hypothesis and Objectives We hypothesized that canine adipose tissue (AT) and bone marrow (BM) MSC could be isolated and expanded equally in PL and FBS at conventionally-used concentrations with differentiation of these MSC unaffected by choice of supplement. Our objectives were to evaluate the use of canine PL in comparison with FBS at four stages: 1) isolation, 2) proliferation, 3) spontaneous differentiation, and 4) directed differentiation. Results 1) Medium with 10% PL was unable to isolate MSC. 2) MSC, initially isolated in FBS-supplemented media, followed a dose-dependent response with no significant difference between PL and FBS cultures at up to 20% (AT) or 30% (BM) enrichment. Beyond these respective peaks, proliferation fell in PL cultures only, while a continued dose-dependent proliferation response was noted in FBS cultures. 3) Further investigation indicated PL expansion culture was inducing spontaneous adipogenesis in concentrations as low as 10% and as early as 4 days in culture. 4) MSC isolated in FBS, but expanded in either FBS or PL, maintained ability to undergo directed adipogenesis and osteogenesis, but not chondrogenesis. Conclusions/Significance Canine PL did not support establishment of MSC colonies from AT and BM, nor expansion of MSC, which appear to undergo spontaneous adipogenesis in response to PL exposure. In vivo studies are warranted to determine if concurrent use of MSC with any platelet-derived products such as platelet-rich plasma are associated with synergistic, neutral or antagonistic effects. PMID:26353112

A Climate Trend Analysis of Niger

USGS Publications Warehouse

Funk, Christopher C.; Rowland, Jim; Eilerts, Gary; Adoum, Alkhalil; White, Libby

2012-01-01

This brief report, drawing from a multi-year effort by the U.S. Agency for International Development (USAID) Famine Early Warning Systems Network (FEWS NET), identifies a substantial recovery of rainfall in Niger, accompanied by increases in air temperatures. These analyses are based on quality-controlled station observations. Conclusions: * Summer rains have increased during the past 20 years and have almost returned to 1960-89 levels. * Temperatures have increased by 0.6° Celsius since 1975, amplifying the effect of droughts. * Crop yields are very low and stagnant, and the population is growing very rapidly. * Niger has offset very rapid population growth with a large expansion of cultivated land. * If the expansion of farmland slows down, stagnant yields and population growth could lead to increased food insecurity.

Monitoring the expansion of built-up areas in Seberang Perai region, Penang State, Malaysia

NASA Astrophysics Data System (ADS)

Samat, N.

2014-02-01

Rapid urbanization has caused land use transformation and encroachment of built environment into arable agriculture land. Uncontrolled expansion could bring negative impacts to society, space and the environment. Therefore, information on expansion and future spatial pattern of built-up areas would be useful for planners and decision makers in formulating policies towards managing and planning for sustainable urban development. This study demonstrates the usage of Geographic Information System in monitoring the expansion of built-up area in Seberang Perai region, Penang State, Malaysia. Built-up area has increased by approximately 20% between 1990 and 2001 and further increased by 12% between 2001 and 2007. New development is expected to continue encroach into existing open space and agriculture area since those are the only available land in this study area. The information on statistics of the expansion of built-up area and future spatial pattern of urban expansion were useful in planning and managing urban spatial growth.

Linear dependence of surface expansion speed on initial plasma temperature in warm dense matter

DOE PAGES

Bang, Woosuk; Albright, Brian James; Bradley, Paul Andrew; ...

2016-07-12

Recent progress in laser-driven quasi-monoenergetic ion beams enabled the production of uniformly heated warm dense matter. Matter heated rapidly with this technique is under extreme temperatures and pressures, and promptly expands outward. While the expansion speed of an ideal plasma is known to have a square-root dependence on temperature, computer simulations presented here show a linear dependence of expansion speed on initial plasma temperature in the warm dense matter regime. The expansion of uniformly heated 1–100 eV solid density gold foils was modeled with the RAGE radiation-hydrodynamics code, and the average surface expansion speed was found to increase linearly withmore » temperature. The origin of this linear dependence is explained by comparing predictions from the SESAME equation-of-state tables with those from the ideal gas equation-of-state. In conclusion, these simulations offer useful insight into the expansion of warm dense matter and motivate the application of optical shadowgraphy for temperature measurement.« less

Supercritical flow characteristics at abrupt expansion structure

NASA Astrophysics Data System (ADS)

Lim, Jia Jun; Puay, How Tion; Zakaria, Nor Azazi

2017-10-01

When dealing with the design of a hydraulic structure, lateral expansion is often necessary for flow emerging at high velocity served as a cross-sectional transition. If the abrupt expansion structure is made to diverge rapidly, it will cause the major part of the flow fail to follow the boundaries. If the transition is too gradual, it will result in a waste of structural material. A preliminary study on the flow structure near the expansion and its relationship with flow parameter is carried out in this study. A two-dimensional depth-averaged model is developed to simulate the supercritical flow at the abrupt expansion structure. Constrained Interpolation Profile (CIP) scheme (which is of third order accuracy) is adopted in the numerical model. Results show that the flow structure and flow characteristics at the abrupt expansion can be reproduced numerically. The validation of numerical result is done against analytical studies. The result from numerical simulation showed good agreement with the analytical solution.

Induction of cell expansion of goldfish melanocytoma cells (GMM-1) by epinephrine and dexamethasone requires external calcium.

PubMed

Shih, Y L; Lo, S J

1993-05-01

Treatment of GMM-1 (a goldfish melanocytoma cell line) cells with epinephrine induced a rapid cell expansion (flattening of cells, extension and broadening of cellular processes) similar to the effect of dexamethasone reported previously (Shih et al., 1990). Studies on the possible involvement of secondary messengers in cell expansion indicated that (i) both 8-bromo-CAMP and forskolin caused cell shrinking (the opposite of cell expansion); (ii) TPA also caused cell shrinking; (iii) phospholipid derivatives, such as 1,2-dioctanoyl-sn-glycerol, lysophosphatidic acid, and arachidonic acid caused cell expansion; and (iv) EGTA (calcium chelator) and nifedipine (calcium channel blocker) inhibited the effect of epinephrine. Together with the previous findings, these observations indicate that epinephrine and dexamethasone may share a common pathway in triggering an external calcium influx to cause cell expansion. The results of the effects of epinephrine agonists and antagonists, together with those of other workers, also show that there are multiple isoforms of adrenoceptor in the goldfish.

Explained in 60 Seconds: A collaboration with Symmetry Magazine, a Fermilab/SLAC publication

NASA Astrophysics Data System (ADS)

Trodden, M.

2011-07-01

The Big Bang refers to the start of the rapid expansion of our Universe. Edwin Hubble discovered this expansion in the 1920s through observations of faraway galaxies, showing that the distances between them are growing as time passes. This stunning discovery is beautifully explained by general relativity — Einstein's theory of gravity — augmented by two new concepts, dark matter and dark energy.

Expansive Cements

DTIC Science & Technology

1970-10-01

plastic or semi- plastic concrete and place no stress on the restraint provided. If, on the other hand, the ettringite continues to form rapidly for too...yield, I and wp.ter-cement ratio. Such a change in cement content may cause a greater change in expansion caracteristics than the change in...the tendency toward plastic shrinkage is increased. During the w’nter znths most structural concrete installations hare had adequate heating and no

Phragmites australis expansion in a restored brackish marsh: documentation at different time scales

USGS Publications Warehouse

Howard, Rebecca J.; Turluck, Theodore D.

2013-01-01

Invasive plants in restored habitats can alter the system such that restoration goals are not met. Non-native lineages of Phragmites australis (hereafter Phragmites) are invasive in North American wetlands, and their presence can be problematic because of decreased species diversity and altered physicochemical processes. Phragmites is a challenging species for restoration because both native and non-native lineages can co-occur. We documented Phragmites expansion in a brackish marsh in Louisiana, USA that was restored with dredged sediments. Invasive Phragmites clones were inadvertently planted at the site. Phragmites expansion was documented through field measurements and aerial imagery. No growth differences were apparent between lineages during the first growing season. Horizontal expansion of 2.27 ± 0.15 m (mean ± 1SE) 5 months after planting occurred through rhizome growth. Seven years after planting, three patches with a combined aerial cover of about 0.7 ha were delineated. The study verified that Phragmites can grow relatively rapidly and persist on dredged sediments. Long-term rapid growth of invasive Phragmites may be a positive attribute in areas subject to high erosion and subsidence rates, despite reductions in species diversity. Acceptability of the presence of invasive Phragmites will depend on restoration goals.

Expansion and Harvesting of hMSC-TERT

PubMed Central

Weber, Christian; Pohl, Sebastian; Pörtner, Ralf; Wallrapp, Christine; Kassem, Moustapha; Geigle, Peter; Czermak, Peter

2007-01-01

The expansion of human mesenchymal stem cells as suspension culture by means of spinner flasks and microcarriers, compared to the cultivation in tissue culture flasks, offers the advantage of reducing the requirements of large incubator capacities as well as reducing the handling effort during cultivation and harvesting. Nonporous microcarriers are preferable when the cells need to be kept in viable condition for further applications like tissue engineering or cell therapy. In this study, the qualification of Biosilon, Cytodex 1, Cytodex 3, RapidCell and P102-L for expansion of hMSC-TERT with an associated harvesting process using either trypsin, accutase, collagenase or a trypsin-accutase mixture was investigated. A subsequent adipogenic differentiation of harvested hMSC-TERT was performed in order to observe possible negative effects on their (adipogenic) differentiation potential as a result of the cultivation and harvesting method. The cultivated cells showed an average growth rate of 0.52 d-1. The cells cultivated on Biosilon, RapidCell and P102-L were harvested succesfully achieving high cell yield and vitalities near 100%. This was not the case for cells on Cytodex 1 and Cytodex 3. The trypsin-accutase mix was most effective. After spinner expansion and harvesting the cells were successfully differentiated to adipocytes. PMID:19662126

Light and Shadows of the Korean Healthcare System

PubMed Central

2012-01-01

This article reviewed achievements and challenges of the National Health Insurance of the Republic of Korea and shared thoughts on its future directions. Starting with large workplaces of 500 or more employees in 1977, Korea's National Health Insurance successfully achieved universal coverage within just 12 yr in 1989. This amazing pace of growth was possible due to a positive combination of strong political will and rapid economic growth. Key features of Korea's experience in achieving universal coverage include 1) gradual expansion of coverage, 2) careful consideration to maintain sound insurance finances, and 3) introducing multiple health insurance societies (multiple payer system) at the initial stage. Introduction of the health insurance has dramatically improved Korea's health indicators and has fueled the rapid growth of basic medical infrastructure including medical institutions and professionals. On the other hand, the successful expansion was not free from side-effects. Although coverage has gradually expanded, benefits are still relatively low. The current situation warrants concern because coverage expansion is driven by welfare populism asserted by irresponsible political slogans and lacks a social consensus on basic principles and philosophy regarding the expansion. Concentration of patients to a few large prestigious hospitals as well as the inefficiencies resulting from a colossal single-payer system should also be pointed out. PMID:22661868

Assessment of the dental and skeletal effects of fan-type rapid maxillary expansion screw and Hyrax screw on craniofacial structures.

PubMed

Gopalakrishnan, Umarevathi; Sridhar, Premkumar

2017-01-01

The purpose of the study was to assess the skeletal and dental effects of fan-type rapid maxillary expansion (RME) appliance and Hyrax RME appliance on the craniofacial structures. The sample of the study included 12 patients with constricted maxillary arches. Acrylic bonded type of attachment was used for both groups. Changes in sagittal, vertical, and transverse relationship were assessed with lateral and frontal cephalograms, respectively. Intercanine and intermolar widths were measured with stone models. Pre- and immediate post-treatment records were statistically analyzed with Wilcoxon signed-rank test. The differences between the groups were evaluated using Mann-Whitney U-test. Since the data pertaining to intercanine width and intermolar width were normally distributed, parametric test of significance (unpaired t -test) was used to compare them. Results showed that Hyrax presented with significantly greater increments for both nasal cavity width and maxillary width when compared to fan-type RME. Both groups had retroclination of incisors. The increase in the intercanine width was almost similar in both groups. Fan-type RME caused only minimal expansion of the intermolar width when compared to the Hyrax. The ratio between the intercanine and intermolar width expansion was nearly 4:1 in the fan-type RME and 0.75:1 in Hyrax.

Bergmann's rule is maintained during a rapid range expansion in a damselfly.

PubMed

Hassall, Christopher; Keat, Simon; Thompson, David J; Watts, Phillip C

2014-02-01

Climate-induced range shifts result in the movement of a sample of genotypes from source populations to new regions. The phenotypic consequences of those shifts depend upon the sample characteristics of the dispersive genotypes, which may act to either constrain or promote phenotypic divergence, and the degree to which plasticity influences the genotype-environment interaction. We sampled populations of the damselfly Erythromma viridulum from northern Europe to quantify the phenotypic (latitude-body size relationship based on seven morphological traits) and genetic (variation at microsatellite loci) patterns that occur during a range expansion itself. We find a weak spatial genetic structure that is indicative of high gene flow during a rapid range expansion. Despite the potentially homogenizing effect of high gene flow, however, there is extensive phenotypic variation among samples along the invasion route that manifests as a strong, positive correlation between latitude and body size consistent with Bergmann's rule. This positive correlation cannot be explained by variation in the length of larval development (voltinism). While the adaptive significance of latitudinal variation in body size remains obscure, geographical patterns in body size in odonates are apparently underpinned by phenotypic plasticity and this permits a response to one or more environmental correlates of latitude during a range expansion. © 2013 John Wiley & Sons Ltd.

Light and shadows of the Korean healthcare system.

PubMed

Moon, Tai Joon

2012-05-01

This article reviewed achievements and challenges of the National Health Insurance of the Republic of Korea and shared thoughts on its future directions. Starting with large workplaces of 500 or more employees in 1977, Korea's National Health Insurance successfully achieved universal coverage within just 12 yr in 1989. This amazing pace of growth was possible due to a positive combination of strong political will and rapid economic growth. Key features of Korea's experience in achieving universal coverage include 1) gradual expansion of coverage, 2) careful consideration to maintain sound insurance finances, and 3) introducing multiple health insurance societies (multiple payer system) at the initial stage. Introduction of the health insurance has dramatically improved Korea's health indicators and has fueled the rapid growth of basic medical infrastructure including medical institutions and professionals. On the other hand, the successful expansion was not free from side-effects. Although coverage has gradually expanded, benefits are still relatively low. The current situation warrants concern because coverage expansion is driven by welfare populism asserted by irresponsible political slogans and lacks a social consensus on basic principles and philosophy regarding the expansion. Concentration of patients to a few large prestigious hospitals as well as the inefficiencies resulting from a colossal single-payer system should also be pointed out.

MAXI/GSC detection of an undergoing soft-to-hard state transition of MAXI J1535-571

NASA Astrophysics Data System (ADS)

Negoro, H.; Sugawara, Y.; Nakajima, M.; Sakamaki, A.; Maruyama, W.; Mihara, T.; Nakahira, S.; Yatabe, F.; Takao, Y.; Matsuoka, M.; Kawai, N.; Sugizaki, M.; Tachibana, Y.; Morita, K.; Sakamoto, T.; Serino, M.; Sugita, S.; Kawakubo, Y.; Hashimoto, T.; Yoshida, A.; Ueno, S.; Tomida, H.; Ishikawa, M.; Isobe, N.; Shimomukai, R.; Ueda, Y.; Tanimoto, A.; Morita, T.; Yamada, S.; Tsuboi, Y.; Iwakiri, W.; Sasaki, R.; Kawai, H.; Sato, T.; Tsunemi, H.; Yoneyama, T.; Yamauchi, M.; Hidaka, K.; Iwahori, S.; Kawamuro, T.; Yamaoka, K.; Shidatsu, M.

2018-06-01

We report an undergoing soft-to-hard state transition of the black hole candidate MAXI J1535-571 in outburst (ATel #10699). After the unexpectedly rapid decrease in the X-ray flux remaining in the soft state from 2018 April 16 (ATel #11568), the source underwent a hard state transition around April 30 (ATel #11611).

Effects of strontium ranelate on bone formation in the mid-palatal suture after rapid maxillary expansion

PubMed Central

Zhao, Shuya; Wang, Xuxia; Li, Na; Chen, Yun; Su, Yuran; Zhang, Jun

2015-01-01

Background The aim of this experimental study was to investigate the effects of strontium ranelate on bone regeneration in the mid-palatal suture in response to rapid maxillary expansion (RME). Methods Thirty-six male 6-week-old Wistar rats were randomly divided into three groups, ie, an expansion only (EO) group, an expansion plus strontium ranelate (SE) group, and a control group. An orthodontic appliance was set between the right and left upper molars of rats with an initial expansive force of 0.98 N. Rats in the SE group were administered strontium ranelate (600 mg/kg body weight) and then euthanized in batches on days 4, 7, and 10. Morphological changes in the mid-palatal suture were investigated using micro-computed tomography and hematoxylin and eosin staining after RME. Bone morphogenetic protein-2 expression in the suture was also examined to evaluate bone formation in the mid-palatal suture. Image-Pro Plus software was then used to determine the mean optical density of the immunohistochemical images. Analysis of variance was used for statistical evaluation at the P<0.05 level. Results With expansive force, the mid-palatal suture was expanded, but there was no statistically significant difference (P>0.05) between the SE and EO groups. The bone volume of the suture decreased after RME, but was higher in the SE group than in the EO group on days 7 and 10. Further, expression of bone morphogenetic protein-2 in the SE group was higher than in the other two groups (P<0.05). Conclusion Strontium ranelate may hasten new bone formation in the expanded mid-palatal suture, which may be therapeutically beneficial in prevention of relapse and shortening the retention period after RME. PMID:26056433

Comparison of the effects of rapid maxillary expansion caused by treatment with either a memory screw or a Hyrax screw on the dentofacial structures--transversal effects.

PubMed

Halıcıoğlu, Koray; Yavuz, Ibrahim

2014-04-01

The aim of the present study was to investigate and compare the effects of conventional Hyrax screw treatment and memory screw treatment on skeletal and dentoalveolar structures. Thirty-two patients with maxillary transversal deficiency were divided into two groups. The memory-screw group included 17 patients (nine females and eight males), while the Hyrax-screw group comprised 15 patients (eight females and seven males). Mean ages of the subjects in the memory-screw and Hyrax-screw groups were 13.00 ± 1.29 and 12.58 ± 1.50 years, respectively. Plaster models and postero-anterior cephalograms were taken from the patients at the beginning of the treatment (T1) and at the end of expansion (T2) and retention periods (T3). The mean expansion period was 7.76 ± 1.04 days in the memory-screw group and 35.46 ± 9.39 days in the Hyrax-screw group. 'Shapiro-Wilk Normality test' was used to determine whether the investigated parameters were homogeneous or not. To determine the treatment changes within the group, 'paired t-test' and 'Wilcoxon signed-ranks test' were applied to the homogeneous and non-homogeneous parameters, respectively. Comparison between the groups was carried out using 'Student's t-test' for homogeneous parameters and 'Mann-Whitney U-test' for the rest. Rapid maxillary expansion was carried out successfully in both the groups. However, the use of memory screw may be advantageous because it shortens the maxillary expansion period, provides additional expansion in the retention period, and generates light forces relative to the conventional Hyrax screw.

Assessing the effects of urbanization and climate change on groundwater management in China

NASA Astrophysics Data System (ADS)

Hua, S.; Zheng, C.

2017-12-01

Groundwater is expected to be more vulnerable in the future due to climate change coupled with rapid urbanization. Thus, protecting future groundwater resources under the impact of urbanization and climate change is necessary towards more sustainable groundwater resource development. This study is intended to shed lights on how water managers may plan for the adverse effects of urbanization and climate change on groundwater quality. A new approach is presented in which the groundwater vulnerability under future climate change scenarios is employed as a constraint to urban expansion. An original form of the Land Transformation Model (LTM) and a revised LTM simulation are applied to model the urbanization. The results indicated that there would be a notable and uneven urban growth between 2010 and 2050. Future groundwater vulnerability is expected to shift significantly under future climate change scenarios. The results of the revised LTM project more urban expansion in the central regions of China, while those of the original LTM project urban expansion in throughout China, although the two projections have the same areas of expansion. The urban expansion simulated by the original LTM follows the historical trend under the drivers of socioeconomic, political and geographic factors. However, the revised LTM drives the urban expansion to the regions with relatively lower groundwater vulnerability, in contrast to the historical trend. This study demonstrates that the integration of LTM and future groundwater vulnerability in the urban planning can better protect the groundwater resource and promote more sustainable socioeconomic development. The methodology developed in this study provides water managers and city planners a useful groundwater management tool for mitigating the risks associated with rapid urbanization and climate change.

Biophysical constraints on leaf expansion in a tall conifer.

PubMed

Meinzer, Frederick C; Bond, Barbara J; Karanian, Jennifer A

2008-02-01

The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water (Psi(L)) and osmotic (Psi(pi)) potential, bulk tissue yield threshold and final needle length were characterized along a height gradient in crowns of > 50-m-tall trees during the period between bud break and full expansion (May to June). Although needle length decreased with increasing height, there was no height-related trend in leaf plastic extensibility, which was highest immediately after bud break (2.9%) and declined rapidly to a stable minimum value (0.3%) over a 3-week period during which leaf expansion was completed. There was a significant positive linear relationship between needle elongation rates and plastic extensibility. Yield thresholds were consistently lower at the upper and middle crown sampling heights. The mean yield threshold across all sampling heights was 0.12 +/- 0.03 MPa on June 8, rising to 0.34 +/- 0.03 MPa on June 15 and 0.45 +/- 0.05 MPa on June 24. Bulk leaf Psi(pi) decreased linearly with increasing height at a rate of 0.004 MPa m(-1) during the period of most rapid needle elongation, but the vertical osmotic gradient was not sufficient to fully compensate for the 0.015 MPa m(-1) vertical gradient in Psi(L), implying that bulk leaf turgor declined at a rate of about 0.011 MPa m(-1) increase in height. Although height-dependent reductions in turgor appeared to constrain leaf expansion, it is possible that the impact of reduced turgor was mitigated by delayed phenological development with increasing height, which resulted in an increase with height in the temperature during leaf expansion.

Mechanics of Failure of High Temperature Metal Matrix Composites

DTIC Science & Technology

1993-12-22

by two inhomogeneities that sustain an eigenstrain loading, proportional to the difference of fiber/matrx thermal expansion coefficients. Utilizing the...appropriate eigenstrain field. sustained by the fiber cross sections. Our primary interest is to determine how the fiber interaction relates to the local...inhomogeneities (fiber cross sections). with a central distance c. undergo an eigenstrain loading. Utilizing the di. -Sacement potentials approach. an

Rethinking the role of myeloid-derived suppressor cells in adoptive T-cell therapy for cancer

PubMed Central

Arina, Ainhoa

2014-01-01

The expansion of cancer-induced myeloid cells is thought to be one of the main obstacles to successful immunotherapy. Nevertheless, in murine tumors undergoing immune-mediated destruction by adoptively transferred T cells, we have recently shown that such cells maintain their immunosuppressive properties. Therefore, adoptive T-cell therapy can, under certain conditions, overcome myeloid cell immunosuppression. PMID:25050213

Ultra-modified rapid sequence induction with transnasal humidified rapid insufflation ventilatory exchange: Challenging convention.

PubMed

Kulkarni, Ketan Sakharam; Dave, Nandini; Saran, Shriyam; Garasia, Madhu; Parelkar, Sandesh

2018-04-01

During positive pressure ventilation, gastric inflation and subsequent pulmonary aspiration can occur. Rapid sequence induction (RSI) technique is an age-old formula to prevent this. We adopted a novel approach of RSI for patients with high risk of aspiration and evaluated it further in patients undergoing laparoscopic surgeries. We believe that, in patients with risk of gastric insufflation and pulmonary aspiration, transnasal humidified rapid-insufflation ventilatory exchange can be useful in facilitating pre- and apnoeic oxygenation till tracheal isolation is achieved.

LED phototherapy on midpalatal suture after rapid maxilla expansion: a Raman spectroscopic study

NASA Astrophysics Data System (ADS)

Rosa, Cristiane B.; Habib, Fernando Antonio L.; de Araújo, Telma M.; dos Santos, Jean N.; Cangussu, Maria Cristina T.; Barbosa, Artur Felipe S.; de Castro, Isabele Cardoso V.; Soares, Luiz Guilherme P.; Pinheiro, Antonio L. B.

2015-03-01

A quick bone formation after maxillary expansion would reduce treatment timeand the biomodulating effects of LED light could contribute for it. The aim of this study was to analyze the effect of LED phototherapy on the acceleration of bone formation at the midpalatal suture after maxilla expansion. Thirty rats divided into 6 groups were used on the study at 2 time points - 7 days: Control; Expansion; and Expansion + LED; and 14 days: Expansion; Expansion + LED in the first week; Expansion and LED in the first and second weeks. LED irradiation occurred at every 48 h during 2 weeks. Expansion was accomplished using a spatula and maintained with a triple helicoid of 0.020" stainless steel orthodontic wire. A LED light (λ850 ± 10nm, 150mW ± 10mW, spot of 0.5cm2, t=120 sec, SAEF of 18J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Near infrared Raman spectroscopic analysis of the suture region was carried and data submitted to statistical analyzes (p≤0.05). Raman spectrum analysis demonstrated that irradiation increased hydroxyapatite in the midpalatal suture after expansion. The results of this indicate that LED irradiation; have a positive biomodulation contributing to the acceleration of bone formation in the midpalatal suture after expansion procedure.

Management of large-scale technology

NASA Technical Reports Server (NTRS)

Levine, A.

1985-01-01

Two major themes are addressed in this assessment of the management of large-scale NASA programs: (1) how a high technology agency was a decade marked by a rapid expansion of funds and manpower in the first half and almost as rapid contraction in the second; and (2) how NASA combined central planning and control with decentralized project execution.

It’s a Jungle Out There! Abiotic and Biotic Factors That Affect Efficacy and Persistence of the Entomopathogenic Fungi

USDA-ARS?s Scientific Manuscript database

One might conclude the soil is a more congenial arena for using entomopathogenic fungi (EPF) than the phylloplane. No ultraviolet light, no rainfall washing conidia from foliage, no rapid attenuation of conidial deposits by rapid plant canopy expansion. The soil is cool, damp and dark – perfect fo...

A study on the interaction and evolution of the spatial expansion and administrative division adjustment in Beijing metropolitan area

NASA Astrophysics Data System (ADS)

Li, Yongfu; Dang, Anrong

2008-10-01

Since 1990s and especially since 2000, the city space of Beijing has grown rapidly. There's no doubt that the urban construction land area is expanding to the suburban areas, which is the result of rapid social and economic growth in the city and also closely related to the reform of "turning county into district". In other words, the adjustment of administrative division in Beijing interacts with the expansion of urban construction land space. Beijing turns counties into districts and introduces regional offices are two distinct evidence. As for the interaction, there're both advantages and disadvantages and the focus of the article is to explore how to exploit the favorable conditions and avoid unfavorable ones. The article takes the town administrative region as the minimum space unit so as to better explore the anisotropism and regional differences of city space expansion as well as the impact caused by the adjustment of administrative divisions. With initial analysis, we find that: firstly, on the contrary to the sharp reduction of farming land, the city construction land are for residential communities, factories and mines increases the fastest; secondly, the big central cluster expansion has great regional difference and the three directions of northwest, north and south grows the fastest, which is mainly caused by the positive guidance of trunk roads including highway construction; thirdly, the land area in central cluster used for new construction projects is mainly located in suburban area, but exurb districts of Daxing and Changping also take up a considerable proportion; fourthly, as for the key exurb towns including Changping, Shunyi, and Fangshan, the built-up area also grows rapidly.

Impacts of future urban expansion on summer climate and heat-related human health in eastern China.

PubMed

Cao, Qian; Yu, Deyong; Georgescu, Matei; Wu, Jianguo; Wang, Wei

2018-03-01

China is the largest and most rapidly urbanizing nation in the world, and is projected to add an additional 200 million city dwellers by the end of 2030. While this rapid urbanization will lead to vast expansion of built-up areas, the possible climate effect and associated human health impact remain poorly understood. Using a coupled urban-atmospheric model, we first examine potential effects of three urban expansion scenarios to 2030 on summer climate in eastern China. Our simulations indicate extensive warming up to 5°C, 3°C, and 2°C in regard to low- (>0%), high- (>75%), and 100% probability urban growth scenarios, respectively. The partitioning of available energy largely explains the changes in 2-m air temperatures, and increased sensible heat flux with higher roughness length of the underlying urban surface is responsible for the increase of nighttime planetary boundary layer height. In the extreme case (the low-probability expansion pathway), the agglomeration of impervious surfaces substantially reduces low-level atmospheric moisture, consequently resulting in large-scale precipitation reduction. However, the effect of near-surface warming far exceeds that of moisture reduction and imposes non-negligible thermal loads on urban residents. Our study, using a scenario-based approach that accounts for the full range of urban growth uncertainty by 2030, helps better evaluate possible regional climate effects and associated human health outcomes in the most rapidly urbanizing areas of China, and has practical implications for the development of sustainable urban regions that are resilient to changes in both mean and extreme conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Formation of phenytoin nanoparticles using rapid expansion of supercritical solution with solid cosolvent (RESS-SC) process.

PubMed

Thakur, Ranjit; Gupta, Ram B

2006-02-03

Nanoparticles are of significant importance in drug delivery. Rapid expansion of supercritical solution (RESS) process can produce pure and high-quality drug particles. However, due to extremely low solubility of polar drugs in supercritical CO(2) (sc CO(2)), RESS has limited commercial applicability. To overcome this major limitation, a modified process rapid expansion of supercritical solution with solid cosolvent (RESS-SC) is proposed which uses a solid cosolvent. Here, the new process is tested for phenytoin drug using menthol solid cosolvent. Phenytoin solubility in pure sc CO(2) is only 3 micromol/mol but when menthol solid cosolvent is used the solubility is enhanced to 1,302 micromol/mol, at 196 bar and 45 degrees C. This 400-fold increase in the solubility can be attributed to the interaction between phenytoin and menthol. Particle agglomeration in expansion zone is another major issue with conventional RESS process. In proposed RESS-SC process solid cosolvent hinders the particle growth resulting in the formation of small nanoparticles. For example, the average particle size of phenytoin in conventional RESS process is 200 nm whereas, with RESS-SC process, the average particle size is 120 nm, at 96 bar and 45 degrees C. Similarly at 196 bar and 45 degrees C, 105 nm average particles were obtained by RESS and 75 nm average particles were obtained in RESS-SC process. The particles obtained were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS) and differential scanning calorimetery (DSC) analyses. Phenytoin nanoparticle production rate in RESS-SC is about 400-fold more in comparison to that in RESS process.

Time-ordered product expansions for computational stochastic system biology.

PubMed

Mjolsness, Eric

2013-06-01

The time-ordered product framework of quantum field theory can also be used to understand salient phenomena in stochastic biochemical networks. It is used here to derive Gillespie's stochastic simulation algorithm (SSA) for chemical reaction networks; consequently, the SSA can be interpreted in terms of Feynman diagrams. It is also used here to derive other, more general simulation and parameter-learning algorithms including simulation algorithms for networks of stochastic reaction-like processes operating on parameterized objects, and also hybrid stochastic reaction/differential equation models in which systems of ordinary differential equations evolve the parameters of objects that can also undergo stochastic reactions. Thus, the time-ordered product expansion can be used systematically to derive simulation and parameter-fitting algorithms for stochastic systems.

Drivers of tall shrub proliferation adjacent to the Dempster Highway, Northwest Territories, Canada

NASA Astrophysics Data System (ADS)

Cameron, Emily A.; Lantz, Trevor C.

2016-04-01

Arctic ecosystems are undergoing rapid changes as a result of climate warming and more frequent disturbances. Disturbances can have particularly large effects on high-latitude ecosystems when ecosystem structure and function is controlled by strong feedbacks between soil conditions, vegetation, and ground thermal regime. In this study we investigated the impact of road construction and maintenance on vegetation structure and biomass along the Dempster Highway where it crosses the Peel Plateau in the Northwest Territories. To explore drivers of tall shrub proliferation and to quantify shrub proliferation in this region of continuous permafrost, greyscale air photos (1975) and Quickbird satellite imagery (2008) were used to map landcover change within two 0.6 km2 belts next to the road and two 0.6 km2 belts 500 m away from the road. Maps showing areas where: 1) tall shrubs expanded, and 2) dwarf shrub tundra resisted invasion were then used to select field sites where a suite of biophysical variables were measured. Rapid tall shrub proliferation and greater biomass adjacent to the road indicate that disturbance can facilitate vegetation change in tundra environments. Our field data also suggests that increased shrub proliferation adjacent to the road was caused by greater soil moisture. Tall shrub proliferation adjacent to the road occurred at lower elevation sites characterized by wetter soils with thicker organic layers. Areas that resisted tall shrub encroachment were located at higher elevations and had drier soils with thin organic layers. Our observations also support previous work illustrating that tall shrub expansion next to the highway promotes strong positive feedbacks to ongoing shrub growth and proliferation.

Shock Initiation of Thermally Expanded TATB

NASA Astrophysics Data System (ADS)

Mulford, Roberta; Swift, Damian

2011-06-01

The plastic-bonded explosive PBX-9502 undergoes unusual hysteretic thermal expansion, or ``ratchet growth'' as a consequence of the uniaxial thermal expansion of the graphitic structure of the major component, TATB explosive. Upon thermal cycling, the density of the material can be reduced by as much as 9%, resulting in a distinct increase in the shock sensitivity of the solid. Run distances to detonation have been measured in thermally expanded samples of PBX-9502, using embedded particle velocity gauges and shock tracker gauges. Uniaxial shocks were generated using a light gas gun, to provide a repeatable stimulus for initiation of detonation. We have applied a porosity model to adjust standard Pop plot data to the reduced density of our samples, to investigate whether the sensitivity of the PBX 9502 increases ideally with the decreasing density, or whether the microscopically non-uniform expansion that occurs during ``ratchet growth'' leads to abnormal sensitivity, possibly as a result of cracking or debonding from the binder, as observed in micrographs of the sample.

Genetic diversity and population history of the red panda (Ailurus fulgens) as inferred from mitochondrial DNA sequence variations.

PubMed

Su, B; Fu, Y; Wang, Y; Jin, L; Chakraborty, R

2001-06-01

The red panda (Ailurus fulgens) is one of the flagship species in worldwide conservation and is of special interest in evolutionary studies due to its taxonomic uniqueness. We sequenced a 236-bp fragment of the mitochondrial D-loop region in a sample of 53 red pandas from two populations in southwestern China. Seventeen polymorphic sites were found, together with a total of 25 haplotypes, indicating a high level of genetic diversity in the red panda. However, no obvious genetic divergence was detected between the Sichuan and Yunnan populations. The consensus phylogenetic tree of the 25 haplotypes was starlike. The pairwise mismatch distribution fitted into a pattern of populations undergoing expansion. Furthermore, Fu's F(S) test of neutrality was significant for the total population (F(S) = -7.573), which also suggests a recent population expansion. Interestingly, the effective population size in the Sichuan population was both larger and more stable than that in the Yunnan population, implying a southward expansion from Sichuan to Yunnan.

Exact finite volume expectation values of local operators in excited states

NASA Astrophysics Data System (ADS)

Pozsgay, B.; Szécsényi, I. M.; Takács, G.

2015-04-01

We present a conjecture for the exact expression of finite volume expectation values in excited states in integrable quantum field theories, which is an extension of an earlier conjecture to the case of general diagonal factorized scattering with bound states and a nontrivial bootstrap structure. The conjectured expression is a spectral expansion which uses the exact form factors and the excited state thermodynamic Bethe Ansatz as building blocks. The conjecture is proven for the case of the trace of the energy-moment tensor. Concerning its validity for more general operators, we provide numerical evidence using the truncated conformal space approach. It is found that the expansion fails to be well-defined for small values of the volume in cases when the singularity structure of the TBA equations undergoes a non-trivial rearrangement under some critical value of the volume. Despite these shortcomings, the conjectured expression is expected to be valid for all volumes for most of the excited states, and as an expansion above the critical volume for the rest.

Uncovering the Role of Hypermethylation by CTG Expansion in Myotonic Dystrophy Type 1 Using Mutant Human Embryonic Stem Cells

PubMed Central

Yanovsky-Dagan, Shira; Avitzour, Michal; Altarescu, Gheona; Renbaum, Paul; Eldar-Geva, Talia; Schonberger, Oshrat; Mitrani-Rosenbaum, Stella; Levy-Lahad, Ephrat; Birnbaum, Ramon Y.; Gepstein, Lior; Epsztejn-Litman, Silvina; Eiges, Rachel

2015-01-01

Summary CTG repeat expansion in DMPK, the cause of myotonic dystrophy type 1 (DM1), frequently results in hypermethylation and reduced SIX5 expression. The contribution of hypermethylation to disease pathogenesis and the precise mechanism by which SIX5 expression is reduced are unknown. Using 14 different DM1-affected human embryonic stem cell (hESC) lines, we characterized a differentially methylated region (DMR) near the CTGs. This DMR undergoes hypermethylation as a function of expansion size in a way that is specific to undifferentiated cells and is associated with reduced SIX5 expression. Using functional assays, we provide evidence for regulatory activity of the DMR, which is lost by hypermethylation and may contribute to DM1 pathogenesis by causing SIX5 haplo-insufficiency. This study highlights the power of hESCs in disease modeling and describes a DMR that functions both as an exon coding sequence and as a regulatory element whose activity is epigenetically hampered by a heritable mutation. PMID:26190529

A MISSING-LINK IN THE SUPERNOVA–GRB CONNECTION: THE CASE OF SN 2012ap

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

Chakraborti, Sayan; Soderberg, Alicia; Kamble, Atish

2015-06-01

Gamma-ray bursts (GRBs) are characterized by ultra-relativistic outflows, while supernovae are generally characterized by non-relativistic ejecta. GRB afterglows decelerate rapidly, usually within days, because their low-mass ejecta rapidly sweep up a comparatively larger mass of circumstellar material. However, supernovae with heavy ejecta can be in nearly free expansion for centuries. Supernovae were thought to have non-relativistic outflows except for a few relativistic ones accompanied by GRBs. This clear division was blurred by SN 2009bb, the first supernova with a relativistic outflow without an observed GRB. However, the ejecta from SN 2009bb was baryon loaded and in nearly free expansion formore » a year, unlike GRBs. We report the first supernova discovered without a GRB but with rapidly decelerating mildly relativistic ejecta, SN 2012ap. We discovered a bright and rapidly evolving radio counterpart driven by the circumstellar interaction of the relativistic ejecta. However, we did not find any coincident GRB with an isotropic fluence of more than one-sixth of the fluence from GRB 980425. This shows for the first time that central engines in SNe Ic, even without an observed GRB, can produce both relativistic and rapidly decelerating outflows like GRBs.« less

A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

DOE PAGES

Schoville, Sean D.; Chen, Yolanda H.; Andersson, Martin N.; ...

2018-01-31

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome andmore » are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. In conclusion, the L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.« less

A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

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

Schoville, Sean D.; Chen, Yolanda H.; Andersson, Martin N.

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome andmore » are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. In conclusion, the L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.« less

A model species for agricultural pest genomics: the genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae).

PubMed

Schoville, Sean D; Chen, Yolanda H; Andersson, Martin N; Benoit, Joshua B; Bhandari, Anita; Bowsher, Julia H; Brevik, Kristian; Cappelle, Kaat; Chen, Mei-Ju M; Childers, Anna K; Childers, Christopher; Christiaens, Olivier; Clements, Justin; Didion, Elise M; Elpidina, Elena N; Engsontia, Patamarerk; Friedrich, Markus; García-Robles, Inmaculada; Gibbs, Richard A; Goswami, Chandan; Grapputo, Alessandro; Gruden, Kristina; Grynberg, Marcin; Henrissat, Bernard; Jennings, Emily C; Jones, Jeffery W; Kalsi, Megha; Khan, Sher A; Kumar, Abhishek; Li, Fei; Lombard, Vincent; Ma, Xingzhou; Martynov, Alexander; Miller, Nicholas J; Mitchell, Robert F; Munoz-Torres, Monica; Muszewska, Anna; Oppert, Brenda; Palli, Subba Reddy; Panfilio, Kristen A; Pauchet, Yannick; Perkin, Lindsey C; Petek, Marko; Poelchau, Monica F; Record, Éric; Rinehart, Joseph P; Robertson, Hugh M; Rosendale, Andrew J; Ruiz-Arroyo, Victor M; Smagghe, Guy; Szendrei, Zsofia; Thomas, Gregg W C; Torson, Alex S; Vargas Jentzsch, Iris M; Weirauch, Matthew T; Yates, Ashley D; Yocum, George D; Yoon, June-Sun; Richards, Stephen

2018-01-31

The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. The L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.

Renal function decline predicted by left atrial expansion index in non-diabetic cohort with preserved systolic heart function.

PubMed

Hsiao, Shih-Hung; Chiou, Kuan-Rau

2017-05-01

Since natriuretic peptide and troponin are associated with renal prognosis and left atrial (LA) parameters are indicators of subclinical cardiovascular abnormalities, this study investigated whether LA expansion index can predict renal decline. This study analysed 733 (69% male) non-diabetic patients with sinus rhythm, preserved systolic function, and estimated glomerular filtration rate (eGFR) higher than 60 mL/min/1.73 m2. In all patients, echocardiograms were performed and LA expansion index was calculated. Renal function was evaluated annually. The endpoint was a downhill trend in renal function with a final eGFR of <60 mL/min/1.73 m2. Rapid renal decline was defined as an annual decline in eGFR >3 mL/min/1.73 m2. The median follow-up time was 5.2 years, and 57 patients (7.8%) had renal function declines (19 had rapid renal declines, and 38 had incidental renal dysfunction). Events were associated with left ventricular mass index, LA expansion index, and heart failure during the follow-up period. The hazard ratio was 1.426 (95% confidence interval, 1.276-1.671; P < 0.0001) per 10% decrease in LA expansion index and was independently associated with an increased event rate. Compared with the highest quartile for the LA expansion index, the lowest quartile had a 9.7-fold risk of renal function decline in the unadjusted model and a 6.9-fold risk after adjusting for left ventricular mass index and heart failure during the follow-up period. Left atrial expansion index is a useful early indicator of renal function decline and may enable the possibility of early intervention to prevent renal function from worsening. NCT01171040. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions, please email: journals.permissions@oup.com.

Trophic overlap between expanding and contracting fish predators in a range margin undergoing change.

PubMed

Westerbom, Mats; Lappalainen, Antti; Mustonen, Olli; Norkko, Alf

2018-05-21

Climate change is predicted to cause a freshening of the Baltic Sea, facilitating range expansions of freshwater species and contractions of marine. Resident marine flounders (Platichthys flesus) and expansive freshwater roach (Rutilus rutilus) are dominant consumers in the Baltic Sea sublittoral where they occur in partial sympatry. By comparing patterns of resource use by flounders and roach along a declining resource gradient of blue mussels (Mytilus trossulus) our aim was to explore predator functional responses and the degree of trophic overlap. Understanding the nature of density-dependent prey acquisition has important implications for predicting population dynamics of both predators and their shared prey. Results showed a highly specialized diet for both species, high reliance on blue mussels throughout the range, similar prey size preference and high trophic overlap. Highest overlap occurred where blue mussels were abundant but overlap was also high where they were scarce. Our results highlight the importance of a single food item - the blue mussel - for both species, likely promoting high population size and range expansion of roach. Findings also suggest that range expansion of roach may have a top-down structuring force on mussels that differ in severity and location from that originating from resident flounders.

Skeletal and dental effects of rapid maxillary expansion assessed through three-dimensional imaging: A multicenter study.

PubMed

Luebbert, Joshua; Ghoneima, Ahmed; Lagravère, Manuel O

2016-03-01

The aim of this study was to determine the skeletal and dental changes in rapid maxillary expansion treatments in two different populations assessed through cone-beam computer tomography (CBCT). Twenty-one patients from Edmonton, Canada and 16 patients from Cairo, Egypt with maxillary transverse deficiency (11-17 years old) were treated with a tooth-borne maxillary expander (Hyrax). CBCTs were obtained from each patient at two time points (initial T1 and at removal of appliance at 3-6 months T2). CBCTs were analyzed using AVIZO software and landmarks were placed on skeletal and dental anatomical structures on the cranial base, maxilla and mandible. Descriptive statistics, intraclass correlation coefficients and one-way ANOVA analysis were used to determine if there were skeletal and dental changes and if these changes were statistically different between both populations. Descriptive statistics show that dental changes were larger than skeletal changes for both populations. Skeletal and dental changes between populations were not statistically different (P<0.05) from each other with the exception of the upper incisor proclination being larger in the Indiana group (P>0.05). Rapid maxillary expansion treatments in different populations demonstrate similar skeletal and dental changes. These changes are greater on the dental structures compared to the skeletal ones in a 4:1 ratio. Copyright © 2015 CEO. Published by Elsevier Masson SAS. All rights reserved.

Cast Off expansion plan by rapid improvement through Optimization tool design, Tool Parameters and using Six Sigma’s ECRS Technique

NASA Astrophysics Data System (ADS)

Gopalakrishnan, T.; Saravanan, R.

2017-03-01

Powerful management concepts step-up the quality of the product, time saving in producing the product thereby increase the production rate, improves tools and techniques, work culture, work place and employee motivation and morale. In this paper discussed about the case study of optimizing the tool design, tool parameters to cast off expansion plan according ECRS technique. The proposed designs and optimal tool parameters yielded best results and meet the customer demand without expansion plan. Hence the work yielded huge savings of money (direct and indirect cost), time and improved the motivation and more of employees significantly.

Advanced Methods for Incorporating Solar Energy Technologies into Electric Sector Capacity-Expansion Models: Literature Review and Analysis

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

Sullivan, P.; Eurek, K.; Margolis, R.

2014-07-01

Because solar power is a rapidly growing component of the electricity system, robust representations of solar technologies should be included in capacity-expansion models. This is a challenge because modeling the electricity system--and, in particular, modeling solar integration within that system--is a complex endeavor. This report highlights the major challenges of incorporating solar technologies into capacity-expansion models and shows examples of how specific models address those challenges. These challenges include modeling non-dispatchable technologies, determining which solar technologies to model, choosing a spatial resolution, incorporating a solar resource assessment, and accounting for solar generation variability and uncertainty.

World's largest macroalgal bloom caused by expansion of seaweed aquaculture in China.

PubMed

Liu, Dongyan; Keesing, John K; Xing, Qianguo; Shi, Ping

2009-06-01

In late June 2008, just weeks before the opening of the Beijing Olympics, a massive green-tide occurred covering about 600km(2) along the coast of Qingdao, host city for Olympic sailing regatta. Coastal eutrophication was quickly attributed with the blame by the international media and some scientists. However, we explored an alternative hypothesis that the cause of the green-tide was due to the rapid expansion of Porphyra yezoensis aquaculture along the coastline over 180km away from Qingdao, and oceanographic conditions which favoured rapid growth of the bloom and contributed to transport of the bloom north into the Yellow Sea and then onshore northwest to Qingdao. At its peak offshore, the bloom covered 1200km(2) and affected 40,000km(2). This is the largest green-tide ever reported, the most extensive translocation of a green-tide and the first case of expansive seaweed aquaculture leading to a green-tide. Given similar oceanographic conditions to those that occurred in 2008, these green-tides may re-occur unless mitigation measures such as those proposed here are taken.

High-Dose Nicotinamide Suppresses ROS Generation and Augments Population Expansion during CD8(+) T Cell Activation.

PubMed

Choi, Ho Jin; Jang, So-Young; Hwang, Eun Seong

2015-10-01

During T cell activation, mitochondrial content increases to meet the high energy demand of rapid cell proliferation. With this increase, the level of reactive oxygen species (ROS) also increases and causes the rapid apoptotic death of activated cells, thereby facilitating T cell homeostasis. Nicotinamide (NAM) has previously been shown to enhance mitochondria quality and extend the replicative life span of human fibroblasts. In this study, we examined the effect of NAM on CD8(+) T cell activation. NAM treatment attenuated the increase of mitochondrial content and ROS in T cells activated by CD3/CD28 antibodies. This was accompanied by an accelerated and higher-level clonal expansion resulting from attenuated apoptotic death but not increased division of the activated cells. Attenuation of ROS-triggered pro-apoptotic events and upregulation of Bcl-2 expression appeared to be involved. Although cells activated in the presence of NAM exhibited compromised cytokine gene expression, our results suggest a means to augment the size of T cell expansion during activation without consuming their limited replicative potential.

Galvanizing Local Resources: A Strategy for Sustainable Development in Rural China

ERIC Educational Resources Information Center

Cho, Eun Ji

2014-01-01

China has been undergoing a rapid development over the past decades, and rural areas are facing a number of challenges in the process of the change. The "New Channel" project, initiated to promote sustainable development and protect natural and cultural heritage in Tongdao county in China from a rapid urbanization and economic…

Deposition of tetracene thin films on SiO2/Si substrates by rapid expansion of supercritical solutions using carbon dioxide

NASA Astrophysics Data System (ADS)

Fujii, Tatsuya; Takahashi, Yuta; Uchida, Hirohisa

2015-03-01

We report on a novel deposition technique of tetracene (naphthacene) thin films on SiO2/Si substrates by rapid expansion of supercritical solutions (RESS) using CO2. Optical microscopy and scanning electron microscopy show that the thin films consist of a high density of submicron-sized grains. The growth mode of the grains followed the Volmer-Weber mode. X-ray diffraction shows that the thin films have regularly arranged structures in both the horizontal and vertical directions of the substrate. A fabricated top-contacted organic thin-film transistor with the tetracene active layer showed p-type transistor characteristics with a field-effect mobility of 5.1 × 10-4 cm2 V-1 s-1.

Bootstrapping rapidity anomalous dimensions for transverse-momentum resummation

DOE PAGES

Li, Ye; Zhu, Hua Xing

2017-01-11

Soft function relevant for transverse-momentum resummation for Drell-Yan or Higgs production at hadron colliders are computed through to three loops in the expansion of strong coupling, with the help of bootstrap technique and supersymmetric decomposition. The corresponding rapidity anomalous dimension is extracted. Furthermore, an intriguing relation between anomalous dimensions for transverse-momentum resummation and threshold resummation is found.

Strategic Vision for Spectrum

DTIC Science & Technology

2010-01-01

wavelengths) associated with radio wave propagation. 3DEPARTMENT OF THE NAVY rapid globalization of spectrum usage impacts Navy and Marine Corps...determining spec- trum policy and use. The rapid globalization of spectrum usage impacts Navy and Marine Corps operations, because the DON mission is...negotiates with other nations to garner their support for U.S. objectives. The global commercial telecommunication market and service capability expansion

The Educational Aspirations of Saudi Arabian Youth: Implications for Creating a New Framework to Explain Saudi Arabian Society

ERIC Educational Resources Information Center

Sim, Woohyang

2016-01-01

Higher education in Saudi Arabia has garnered immense praise for its rapid expansion and developments in both quantity and quality. In response to this, the tertiary school enrollment in Saudi Arabia is rapidly rising. These achievements can be explained by changes in educational policies. However, studies regarding youth's awareness are scarce.…

Mapping impervious surface expansion using medium resolution satellite image time series: A case study in Yangtze river delta, China

USDA-ARS?s Scientific Manuscript database

Due to the rapid growth of population and economic development in the developing countries, more people are now living in the cities than in the rural areas in the world for the first time in human history. As a result, cities are sprawling rapidly into their surroundings. A characteristic change as...

Health system's response for physician workforce shortages and the upcoming crisis in Ethiopia: a grounded theory research.

PubMed

Assefa, Tsion; Haile Mariam, Damen; Mekonnen, Wubegzier; Derbew, Miliard

2017-12-28

A rapid transition from severe physician workforce shortage to massive production to ensure the physician workforce demand puts the Ethiopian health care system in a variety of challenges. Therefore, this study discovered how the health system response for physician workforce shortage using the so-called flooding strategy was viewed by different stakeholders. The study adopted the grounded theory research approach to explore the causes, contexts, and consequences (at the present, in the short and long term) of massive medical student admission to the medical schools on patient care, medical education workforce, and medical students. Forty-three purposively selected individuals were involved in a semi-structured interview from different settings: academics, government health care system, and non-governmental organizations (NGOs). Data coding, classification, and categorization were assisted using ATLAs.ti qualitative data analysis scientific software. In relation to the health system response, eight main categories were emerged: (1) reasons for rapid medical education expansion; (2) preparation for medical education expansion; (3) the consequences of rapid medical education expansion; (4) massive production/flooding as human resources for health (HRH) development strategy; (5) cooperation on HRH development; (6) HRH strategies and planning; (7) capacity of system for HRH development; and (8) institutional continuity for HRH development. The demand for physician workforce and gaining political acceptance were cited as main reasons which motivated the government to scale up the medical education rapidly. However, the rapid expansion was beyond the capacity of medical schools' human resources, patient flow, and size of teaching hospitals. As a result, there were potential adverse consequences in clinical service delivery, and teaching learning process at the present: "the number should consider the available resources such as number of classrooms, patient flows, medical teachers, library…". In the future, it was anticipated to end in surplus in physician workforce, unemployment, inefficiency, and pressure on the system: "…flooding may seem a good strategy superficially but it is a dangerous strategy. It may put the country into crisis, even if good physicians are being produced; they may not get a place where to go…". Massive physician workforce production which is not closely aligned with the training capacity of the medical schools and the absorption of graduates in to the health system will end up in unanticipated adverse consequences.

Tropical vegetation evidence for rapid sea level changes associated with Heinrich Events

NASA Astrophysics Data System (ADS)

González, Catalina; Dupont, Lydie M.

2010-03-01

A Cariaco Basin pollen record shows the development of tropical salt marshes during marine isotope stage 3. Rapid and abrupt expansions of salt marsh vegetation in tropical South America are associated with north Atlantic Heinrich Events stadials (HE-stadials). Intervals of salt marsh expansion have an internal structure, which consists of a recurrent alternation of species that starts with pollen increments of Chenopodiaceae, that are followed by increments of grasses, and subsequently by increments of Cyperaceae. This pattern suggests a successional process that is determined by the close relationship between sea-level and plant community dynamics. The salt tolerant Chenopodiaceae, indicate hypersaline intertidal environments, which were most likely promoted by extremely dry atmospheric conditions. Rapid sea-level rise characterizes the onset of HE-stadials, causing the continued recruitment of pioneer species, which are the only ones tolerating rapid rates of disturbance. Once sea-level rise decelerates, marsh plants are able to trap and stabilize sediments, favouring the establishment of more competitive species. These results add to the scarce knowledge on the dynamics of tropical salt marsh ecosystems, and provide independent paleoclimatic evidence on sea-level changes following Antarctic climate variability.

Strategic camouflage treatment of skeletal Class III malocclusion (mandibular prognathism) using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy.

PubMed

Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald

2016-01-01

This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

A staggered conservative scheme for every Froude number in rapidly varied shallow water flows

NASA Astrophysics Data System (ADS)

Stelling, G. S.; Duinmeijer, S. P. A.

2003-12-01

This paper proposes a numerical technique that in essence is based upon the classical staggered grids and implicit numerical integration schemes, but that can be applied to problems that include rapidly varied flows as well. Rapidly varied flows occur, for instance, in hydraulic jumps and bores. Inundation of dry land implies sudden flow transitions due to obstacles such as road banks. Near such transitions the grid resolution is often low compared to the gradients of the bathymetry. In combination with the local invalidity of the hydrostatic pressure assumption, conservation properties become crucial. The scheme described here, combines the efficiency of staggered grids with conservation properties so as to ensure accurate results for rapidly varied flows, as well as in expansions as in contractions. In flow expansions, a numerical approximation is applied that is consistent with the momentum principle. In flow contractions, a numerical approximation is applied that is consistent with the Bernoulli equation. Both approximations are consistent with the shallow water equations, so under sufficiently smooth conditions they converge to the same solution. The resulting method is very efficient for the simulation of large-scale inundations.

Intelligent Visual Input: A Graphical Method for Rapid Entry of Patient-Specific Data

PubMed Central

Bergeron, Bryan P.; Greenes, Robert A.

1987-01-01

Intelligent Visual Input (IVI) provides a rapid, graphical method of data entry for both expert system interaction and medical record keeping purposes. Key components of IVI include: a high-resolution graphic display; an interface supportive of rapid selection, i.e., one utilizing a mouse or light pen; algorithm simplification modules; and intelligent graphic algorithm expansion modules. A prototype IVI system, designed to facilitate entry of physical exam findings, is used to illustrates the potential advantages of this approach.

Blocking Glycolytic Metabolism Increases Memory T Cells and Antitumor Function | Center for Cancer Research

Cancer.gov

CD8+ T cells are a major component of the cellular immune response, which is necessary to control a variety of bacterial and viral infections. CD8+ T cells also play a major role in the cell-mediated antitumor immune response. After encountering antigen, naïve CD8+ T cells undergo an extensive period of proliferation and expansion, and differentiate into effector cells and

An unusual foreign body in the upper aerodigestive tract: esophageal obstruction due to bran impaction.

PubMed

Losacco, T; Cagiano, R; Luperto, P; Bera, I; Santacroce, L

2009-01-01

Foreign bodies of the upper aerodigestive tract are common problems encountered by the otolaryngologist and general surgeons. While the diagnosis seems straightforward, it is sometimes delayed until after serious complications have occurred. The treatment of choice is endoscopic retrieval under general anesthesia. The procedure should be preceded by the completion of appropriate studies (radiographic and other specifically indicated for the patient) planned and performed by the endoscopy team. Time invested in preparation and planning will usually yield a speedy recovery of the patient. Bran is a natural fiber that undergoes considerable expansion and thickening when hydrated. Due to this property, it has been used in "weight loss" tablets that in the stomach undergo expansion and are expected to cause early satiety. These tablets are usually marketed as over-the-counter (OTC) diet products by a number of pharmaceutical manufacturers. These supplements consisting primarily of dietary fibers, so common and inoffensive-seeming, rarely may have severe side effects, such a sudden esophageal obstruction. We report a case of a bran dietary product impacted in the cervical esophagus in a 45 year old woman, presenting as an emergency complaining of retrosternal discomfort and difficult to swallow or drink. The technique for removal of such object that is also reported.

Nano-Pore Size Analysis by SAXS Method of Cementitious Mortars Undergoing Delayed Ettringite Formation

NASA Astrophysics Data System (ADS)

Shekar, Yamini

This research investigates the nano-scale pore structure of cementitious mortars undergoing delayed ettringite formation (DEF) using small angle x-ray scattering (SAXS). DEF has been known to cause expansion and cracking during later ages (around 4000 days) in concrete that has been heat cured at temperatures of 70°C or above. Though DEF normally occurs in heat cured concrete, mass cured concrete can also experience DEF. Large crystalline pressures result in smaller pore sizes. The objectives of this research are: (1) to investigate why some samples expand early than later expansion, (2) to evaluate the effects of curing conditions and pore size distributions at high temperatures, and (3) to assess the evolution of the pore size distributions over time. The most important outcome of the research is the pore sizes obtained from SAXS were used in the development of a 3-stage model. From the data obtained, the pore sizes increase in stage 1 due to initial ettringite formation and in turn filling up the smallest pores. Once the critical pore size threshold is reached (around 20nm) stage 2 is formed due to cracking which tends to decrease in the pore sizes. Finally, in stage 3, the cracking continues, therefore increasing in the pore size.

Expansion and redifferentiation of chondrocytes from osteoarthritic cartilage: cells for human cartilage tissue engineering.

PubMed

Hsieh-Bonassera, Nancy D; Wu, Iwen; Lin, Jonathan K; Schumacher, Barbara L; Chen, Albert C; Masuda, Koichi; Bugbee, William D; Sah, Robert L

2009-11-01

To determine if selected culture conditions enhance the expansion and redifferentiation of chondrocytes isolated from human osteoarthritic cartilage with yields appropriate for creation of constructs for treatment of joint-scale cartilage defects, damage, or osteoarthritis. Chondrocytes isolated from osteoarthritic cartilage were analyzed to determine the effects of medium supplement on cell expansion in monolayer and then cell redifferentiation in alginate beads. Expansion was assessed as cell number estimated from DNA, growth rate, and day of maximal growth. Redifferentiation was evaluated quantitatively from proteoglycan and collagen type II content, and qualitatively by histology and immunohistochemistry. Using either serum or a growth factor cocktail (TFP: transforming growth factor beta1, fibroblast growth factor 2, and platelet-derived growth factor type bb), cell growth rate in monolayer was increased to 5.5x that of corresponding conditions without TFP, and cell number increased 100-fold within 17 days. In subsequent alginate bead culture with human serum or transforming growth factor beta1 and insulin-transferrin-selenium-linoleic acid-bovine serum albumin, redifferentiation was enhanced with increased proteoglycan and collagen type II production. Effects of human serum were dose dependent, and 5% or higher induced formation of chondron-like structures with abundant proteoglycan-rich matrix. Chondrocytes from osteoarthritic cartilage can be stimulated to undergo 100-fold expansion and then redifferentiation, suggesting that they may be useful as a cell source for joint-scale cartilage tissue engineering.

Global Solar Magnetic Field Organization in the Outer Corona: Influence on the Solar Wind Speed and Mass Flux Over the Cycle

NASA Astrophysics Data System (ADS)

Réville, Victor; Brun, Allan Sacha

2017-11-01

The dynamics of the solar wind depends intrinsically on the structure of the global solar magnetic field, which undergoes fundamental changes over the 11-year solar cycle. For instance, the wind terminal velocity is thought to be anti-correlated with the expansion factor, a measure of how the magnetic field varies with height in the solar corona, usually computed at a fixed height (≈ 2.5 {R}⊙ , the source surface radius that approximates the distance at which all magnetic field lines become open). However, the magnetic field expansion affects the solar wind in a more detailed way, its influence on the solar wind properties remaining significant well beyond the source surface. We demonstrate this using 3D global magnetohydrodynamic (MHD) simulations of the solar corona, constrained by surface magnetograms over half a solar cycle (1989-2001). A self-consistent expansion beyond the solar wind critical point (even up to 10 {R}⊙ ) makes our model comply with observed characteristics of the solar wind, namely, that the radial magnetic field intensity becomes latitude independent at some distance from the Sun, and that the mass flux is mostly independent of the terminal wind speed. We also show that near activity minimum, the expansion in the higher corona has more influence on the wind speed than the expansion below 2.5 {R}⊙ .

Delayed effects of chlorpyrifos across metamorphosis on dispersal-related traits in a poleward moving damselfly.

PubMed

Dinh, Khuong Van; Janssens, Lizanne; Therry, Lieven; Bervoets, Lieven; Bonte, Dries; Stoks, Robby

2016-11-01

How exposure to contaminants may interfere with the widespread poleward range expansions under global warming is largely unknown. Pesticide exposure may negatively affect traits shaping the speed of range expansion, including traits related to population growth rate and dispersal-related traits. Moreover, rapid evolution of growth rates during poleward range expansions may come at a cost of a reduced investment in detoxification and repair thereby increasing the vulnerability to contaminants at expanding range fronts. We tested effects of a sublethal concentration of the widespread pesticide chlorpyrifos on traits related to range expansion in replicated edge and core populations of the poleward moving damselfly Coenagrion scitulum reared at low and high food levels in a common garden experiment. Food limitation in the larval stage had strong negative effects both in the larval stage and across metamorphosis in the adult stage. Exposure to chlorpyrifos during the larval stage did not affect larval traits but caused delayed effects across metamorphosis by increasing the incidence of wing malformations during metamorphosis and by reducing a key component of the adult immune response. There was some support for an evolutionary trade-off scenario as the faster growing edge larvae suffered a higher mortality during metamorphosis. Instead, there was no clear support for the faster growing edge larvae being more vulnerable to chlorpyrifos. Our data indicate that sublethal delayed effects of pesticide exposure, partly in association with the rapid evolution of faster growth rates, may slow down range expansions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of two preoperative protocols for mandibular symphyseal distraction osteogenesis to reduce the risk of tooth damage.

PubMed

Winsauer, Heinz; Ploder, Oliver; Juengling, Katharina; Walter, Andre; Kolk, Andreas

2017-04-01

Two techniques to separate the lower incisors prior to mandibular symphyseal distraction osteogenesis (MSDO) were evaluated with respect to avoiding tooth damage. Fifty patients (20.2 ± 7.0 years) requiring MSDO were treated with a tooth-borne appliance by utilizing two preoperative protocols to separate the central incisors: i) brackets and a V-bent wire with an open coil spring (two-step; TS; n = 24) and ii) a wire attached from the appliance to the central incisors with subsequent dento-alveolar expansion prior to surgery (one-step; OS; n = 26). The distance between the lower incisors was measured preoperatively on radiographs and measurements at the cast models were performed. Complications and radiographs were analyzed. The mean distance (±SD) between the lower central incisors for OS and TS prior to surgery was 3.44 ± 1.05 and 3.18 ± 1.13 mm, respectively. The mean expansion for OS and TS was 4.3 ± 2.9 and 4.3 ± 2.7 mm at the dental level and 3.8 ± 3.2 and 4.0 ± 2.1 mm at the bone level, respectively. Four patients undergoing the TS and one patient undergoing the OS showed transient dental complications. Pre-surgical dento-alveolar expansion by utilizing a one-step technique to separate the lower central incisors reduces the risk of permanent tooth damage and weakens the mandibular bone in the midline. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Advanced and specialist nursing practice: attitudes of nurses and physicians in Israel.

PubMed

Brodsky, Eithan; Van Dijk, Dina

2008-01-01

With the introduction of new and advanced nursing roles, the nursing profession is undergoing dynamic change. Realizing changes will be easier to accomplish if the nursing community and other healthcare professionals welcome the process. Recently the nursing staff mix in Israel has been undergoing a transformation: encouraging registered nurses to enhance their status by acquiring academic degrees and advanced professional training, and initiating the adoption of new nursing roles. Our goal is to evaluate Israeli nurses' and physicians' attitudes to the introduction of new nursing roles and to expanding the scope of nursing practice. Two hundred and fifteen nurses and 110 physicians from three large general hospitals and 15 community clinics filled in a questionnaire. In general the majority of the nurses supported expansion of nursing practice, and such expansion did not cause significant opposition among physicians. However when the task affected patients' health, physicians were less willing to permit nurses to perform skills previously their responsibility alone. In addition, using multiple logistic regressions, support of the expansion of nursing practice was significantly higher among nurses in management or training positions, and among academically accredited nurses. Support for expanded roles was prominent among hospital physicians, graduates from Israeli schools of medicine, and less-tenured physicians. We suggest that confirmation by various groups of physicians and nurses of standardized definitions of the new boundaries in the scope of nursing practice roles could successfully promote development of new roles and facilitate integration of the Israeli healthcare system into the global context of change. Inter- and intra-professional collaboration, agreement, and understanding regarding advanced nursing practice roles and their introduction into the healthcare system might improve the relationship between healthcare professions and ultimately increase quality of care and patient satisfaction.

Thermal noise in a boost-invariant matter expansion in relativistic heavy-ion collisions

NASA Astrophysics Data System (ADS)

Chattopadhyay, Chandrodoy; Bhalerao, Rajeev S.; Pal, Subrata

2018-05-01

We formulate a general theory of thermal fluctuations within causal second-order viscous hydrodynamic evolution of matter formed in relativistic heavy-ion collisions. The fluctuation is treated perturbatively on top of a boost-invariant longitudinal expansion. Numerical simulation of thermal noise is performed for a lattice quantum chromodynamics equation of state and for various second-order dissipative evolution equations. Phenomenological effects of thermal fluctuations on the two-particle rapidity correlations are studied.

Early and Definitive Diagnosis of Toxic Shock Syndrome by Detection of Marked Expansion of T-Cell-Receptor Vβ2-Positive T Cells

PubMed Central

Kato, Hidehito; Yamada, Ritsuko; Okano, Hiroya; Ohta, Hiroaki; Imanishi, Ken’ichi; Kikuchi, Ken; Totsuka, Kyouichi; Uchiyama, Takehiko

2003-01-01

We describe two cases of early toxic shock syndrome, caused by the superantigen produced from methicillin-resistant Staphylococcus aureus and diagnosed on the basis of an expansion of T-cell-receptor Vβ2-positive T cells. One case-patient showed atypical symptoms. Our results indicate that diagnostic systems incorporating laboratory techniques are essential for rapid, definitive diagnosis of toxic shock syndrome. PMID:12643839

Urbanization Process Monitoring in Northwest China based on DMSP/OLS Nighttime Light Data

NASA Astrophysics Data System (ADS)

Wang, K.; Bai, L. Y.; Feng, J. Z.

2017-02-01

In recent years, the DMSP/OLS nighttime light data have been widely applied to various fields such as monitoring and evaluation of urbanization, estimation of social economy, economical environment and health effects, hazards analysis, and fisheries research. The general urbanized level in China has rapidly developed since the 1990s, and the cities in northwest China, which were important population centres of the ancient silk road, have also been developed in a high speed thanks to China’s national strategy of Western Development. Given the Xinjiang autonomous region as a core area of One Belt and One Road, it is very necessary to study the urbanization processes and changes of its urban system and the whole northwest region of China. In this paper, we extracted built-up areas of the cities in northwest China in 1992, 1997, 2002, 2007, and 2012, evaluated urban expansion and spatial pattern through appropriate indexes, and also quantitatively analyzed the urbanized level of each city. The results showed that the cities in northwest China generally presented high strong and rapid expansion, but there were some large differences among cities. Urban expansion forms alternate with exterior expansion and interior filling, in general, the cities externally expandedafter 2002 and internally filledbefore 2002, meanwhile, there were a high positive correlation between urban built-up areas and population growth in Xinjiang autonomous.

Investigation of Key Parameters of Rock Cracking Using the Expansion of Vermiculite Materials

PubMed Central

Ahn, Chi-Hyung; Hu, Jong Wan

2015-01-01

The demand for the development of underground spaces has been sharply increased in lieu of saturated ground spaces because the residents of cities have steadily increased since the 1980s. The traditional widely used excavation methods (i.e., explosion and shield) have caused many problems, such as noise, vibration, extended schedule, and increased costs. The vibration-free (and explosion-free) excavation method has currently attracted attention in the construction site because of the advantage of definitively solving these issues. For such reason, a new excavation method that utilizes the expansion of vermiculite with relatively fewer defects is proposed in this study. In general, vermiculite materials are rapidly expanded in volume when they receive thermal energy. Expansion pressure can be produced by thermal expansion of vermiculite in a steel tube, and measured by laboratory tests. The experimental tests are performed with various influencing parameters in an effort to seek the optimal condition to effectively increase expansion pressure at the same temperature. Then, calibrated expansion pressure is estimated, and compared to each model. After analyzing test results for expansion pressure, it is verified that vermiculite expanded by heat can provide enough internal pressure to break hard rock during tunneling work. PMID:28793610

Investigation of Key Parameters of Rock Cracking Using the Expansion of Vermiculite Materia.

PubMed

Ahn, Chi-Hyung; Hu, Jong Wan

2015-10-12

The demand for the development of underground spaces has been sharply increased in lieu of saturated ground spaces because the residents of cities have steadily increased since the 1980s. The traditional widely used excavation methods ( i.e ., explosion and shield) have caused many problems, such as noise, vibration, extended schedule, and increased costs. The vibration-free (and explosion-free) excavation method has currently attracted attention in the construction site because of the advantage of definitively solving these issues. For such reason, a new excavation method that utilizes the expansion of vermiculite with relatively fewer defects is proposed in this study. In general, vermiculite materials are rapidly expanded in volume when they receive thermal energy. Expansion pressure can be produced by thermal expansion of vermiculite in a steel tube, and measured by laboratory tests. The experimental tests are performed with various influencing parameters in an effort to seek the optimal condition to effectively increase expansion pressure at the same temperature. Then, calibrated expansion pressure is estimated, and compared to each model. After analyzing test results for expansion pressure, it is verified that vermiculite expanded by heat can provide enough internal pressure to break hard rock during tunneling work.

Utilization of Surveillance after Polypectomy in the Medicare Population – A Cohort Study

PubMed Central

Lansdorp-Vogelaar, Iris; Fedewa, Stacey; Lin, Chun Chieh; Virgo, Katherine S.; Jemal, Ahmedin

2014-01-01

Background Surveillance in patients with previous polypectomy was underused in the Medicare population in 1994. This study investigates whether expansion of Medicare reimbursement for colonoscopy screening in high-risk individuals has reduced the inappropriate use of surveillance. Methods We used Kaplan-Meier analysis to estimate time to surveillance and polyp recurrence rates for Medicare beneficiaries with a colonoscopy with polypectomy between 1998 and 2003 who were followed through 2008 for receipt of surveillance colonoscopy. Generalized Estimating Equations were used to estimate risk factors for: 1) failing to undergo surveillance and 2) polyp recurrence among these individuals. Analyses were stratified into three 2-year cohorts based on baseline colonoscopy date. Results Medicare beneficiaries undergoing a colonoscopy with polypectomy in the 1998–1999 (n = 4,136), 2000–2001 (n = 3,538) and 2002–2003 (n = 4,655) cohorts had respective probabilities of 30%, 26% and 20% (p<0.001) of subsequent surveillance events within 3 years. At the same time, 58%, 52% and 45% (p<0.001) of beneficiaries received a surveillance event within 5 years. Polyp recurrence rates after 5 years were 36%, 30% and 26% (p<0.001) respectively. Older age (≥ 70 years), female gender, later cohort (2000–2001 & 2002–2003), and severe comorbidity were the most important risk factors for failure to undergo a surveillance event. Male gender and early cohort (1998–1999) were the most important risk factors for polyp recurrence. Conclusions Expansion of Medicare reimbursement for colonoscopy screening in high-risk individuals has not reduced underutilization of surveillance in the Medicare population. It is important to take action now to improve this situation, because polyp recurrence is substantial in this population. PMID:25393312

Carbon Dioxide-Based versus Saline Tissue Expansion for Breast Reconstruction: Results of the XPAND Prospective, Randomized Clinical Trial.

PubMed

Ascherman, Jeffrey A; Zeidler, Kamakshi; Morrison, Kerry A; Appel, James Z; Berkowitz, R L; Castle, John; Colwell, Amy; Chun, Yoon; Johnson, Debra; Mohebali, Khashayar

2016-12-01

AeroForm is a new type of remote-controlled, needle-free, carbon dioxide-based expander involving a potentially faster method of tissue expansion. Results are presented here from the AirXpanders Patient Activated Controlled Tissue Expander pivotal trial comparing AeroForm to saline tissue expanders. Women undergoing two-stage breast reconstruction were randomized at 17 U.S. sites in this U.S. Food and Drug Administration-approved investigational device exemption trial. Expansion in the investigational arm was performed by the patient in 10-cc increments up to 30 cc/day of carbon dioxide and in the control arm by the physician with periodic bolus injections of saline. Safety endpoints, expansion and reconstruction times, pain, and satisfaction were assessed. One hundred fifty women were treated: 98 with carbon dioxide expanders (n = 168) and 52 with saline expanders (n = 88). The treatment success rate (all breasts exchanged successfully excluding non-device-related failures) was 96.1 percent for carbon dioxide and 98.8 percent for saline. Median time to full expansion and completion of the second-stage operation was 21.0 and 108.5 days (carbon dioxide) versus 46.0 and 136.5 days (saline), respectively, with a similar rate of overall complications. Ease of use for the carbon dioxide expander was rated high by patients (98 percent) and physicians (90 percent). The AirXpanders Patient Activated Controlled Tissue Expander trial results demonstrate that a carbon dioxide-based expander is an effective method of tissue expansion with a similar overall adverse event rate compared to saline expanders, and provides a more convenient and expedient expansion. Therapeutic, I.

Cosmological models constructed by van der Waals fluid approximation and volumetric expansion

NASA Astrophysics Data System (ADS)

Samanta, G. C.; Myrzakulov, R.

The universe modeled with van der Waals fluid approximation, where the van der Waals fluid equation of state contains a single parameter ωv. Analytical solutions to the Einstein’s field equations are obtained by assuming the mean scale factor of the metric follows volumetric exponential and power-law expansions. The model describes a rapid expansion where the acceleration grows in an exponential way and the van der Waals fluid behaves like an inflation for an initial epoch of the universe. Also, the model describes that when time goes away the acceleration is positive, but it decreases to zero and the van der Waals fluid approximation behaves like a present accelerated phase of the universe. Finally, it is observed that the model contains a type-III future singularity for volumetric power-law expansion.

Blood Volume: Importance and Adaptations to Exercise Training, Environmental Stresses and Trauma/Sickness

NASA Technical Reports Server (NTRS)

Sawka, Michael N.; Convertino, Victor A.; Eichner, E. Randy; Schnieder, Suzanne M.; Young, Andrew J.

2000-01-01

This paper reviews the influence of several perturbations (physical exercise, heat stress, terrestrial altitude, microgravity, and trauma/sickness) on adaptations of blood volume (BV), erythrocyte volume (EV), and plasma volume (PV). Exercise training can induced BV expansion; PV expansion usually occurs immediately, but EV expansion takes weeks. EV and PV expansion contribute to aerobic power improvements associated with exercise training. Repeated heat exposure induces PV expansion but does not alter EV. PV expansion does not improve thermoregulation, but EV expansion improves thermoregulation during exercise in the heat. Dehydration decreases PV (and increases plasma tonicity) which elevates heat strain and reduces exercise performance. High altitude exposure causes rapid (hours) plasma loss. During initial weeks at altitude, EV is unaffected, but a gradual expansion occurs with extended acclimatization. BV adjustments contribute, but are not key, to altitude acclimatization. Microgravity decreases PV and EV which contribute to orthostatic intolerance and decreased exercise capacity in astronauts. PV decreases may result from lower set points for total body water and central venous pressure, which EV decrease bay result form increased erythrocyte destruction. Trauma, renal disease, and chronic diseases cause anemia from hemorrhage and immune activation, which suppressions erythropoiesis. The re-establishment of EV is associated with healing, improved life quality, and exercise capabilities for these injured/sick persons.

Evolution of density-dependent movement during experimental range expansions.

PubMed

Fronhofer, E A; Gut, S; Altermatt, F

2017-12-01

Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Differential gene expression in Daphnia magna suggests distinct modes of action and bioavailability for ZnO nanoparticles and Zn ions

EPA Science Inventory

Zinc oxide nanoparticles (ZnO NPs) are being rapidly developed for use in consumer products, wastewater treatment and chemotherapy, providing several possible routes for ZnO NP exposure to humans and aquatic organisms. Recent studies have shown that ZnO NPs undergo rapid dissolut...

Neutron diffraction determination of the cell dimensions and thermal expansion of the fluoroperovskite KMgF3 from 293 to 3.6 K

NASA Astrophysics Data System (ADS)

Mitchell, Roger H.; Cranswick, Lachlan M. D.; Swainson, Ian

2006-11-01

The cell dimensions of the fluoroperovskite KMgF3 synthesized by solid state methods have been determined by powder neutron diffraction and Rietveld refinement over the temperature range 293 3.6 K using Pt metal as an internal standard for calibration of the neutron wavelength. These data demonstrate conclusively that cubic Pmoverline{3} m KMgF3 does not undergo any phase transitions to structures of lower symmetry with decreasing temperature. Cell dimensions range from 3.9924(2) Å at 293 K to 3.9800(2) Å at 3.6 K, and are essentially constant within experimental error from 50 to 3.6 K. The thermal expansion data are described using a fourth order polynomial function.

Breeding bird response to juniper woodland expansion

USGS Publications Warehouse

Rosenstock, Steven S.; van Riper, Charles

2001-01-01

In recent times, pinyon (Pinus spp.)-juniper (Juniperus spp.) woodlands have expanded into large portions of the Southwest historically occupied by grassland vegetation. From 1997-1998, we studied responses of breeding birds to one-seed juniper (J. monosperma) woodland expansion at 2 grassland study areas in northern Arizona. We sampled breeding birds in 3 successional stages along a grassland-woodland gradient: un-invaded grassland, grassland undergoing early stages of juniper establishment, and developing woodland. Species composition varied greatly among successional stages and was most different between endpoints of the gradient. Ground-nesting grassland species predominated in uninvaded grassland but declined dramatically as tree density increased. Tree- and cavity-nesting species increased with tree density and were most abundant in developing woodland. Restoration of juniper-invaded grasslands will benefit grassland-obligate birds and other wildlife.

Spot sign on 90-second delayed computed tomography angiography improves sensitivity for hematoma expansion and mortality: prospective study.

PubMed

Ciura, Viesha A; Brouwers, H Bart; Pizzolato, Raffaella; Ortiz, Claudia J; Rosand, Jonathan; Goldstein, Joshua N; Greenberg, Steven M; Pomerantz, Stuart R; Gonzalez, R Gilberto; Romero, Javier M

2014-11-01

The computed tomography angiography (CTA) spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage. The spot sign has proven to be a dynamic entity, with multimodal imaging proving to be of additional value. We investigated whether the addition of a 90-second delayed CTA acquisition would capture additional intracerebral hemorrhage patients with the spot sign and increase the sensitivity of the spot sign. We prospectively enrolled consecutive intracerebral hemorrhage patients undergoing first pass and 90-second delayed CTA for 18 months at a single academic center. Univariate and multivariate logistic regression were performed to assess clinical and neuroimaging covariates for relationship with hematoma expansion and mortality. Sensitivity of the spot sign for hematoma expansion on first pass CTA was 55%, which increased to 64% if the spot sign was present on either CTA acquisition. In multivariate analysis the spot sign presence was associated with significant hematoma expansion: odds ratio, 17.7 (95% confidence interval, 3.7-84.2; P=0.0004), 8.3 (95% confidence interval, 2.0-33.4; P=0.004), and 12.0 (95% confidence interval, 2.9-50.5; P=0.0008) if present on first pass, delayed, or either CTA acquisition, respectively. Spot sign presence on either acquisitions was also significant for mortality. We demonstrate improved sensitivity for predicting hematoma expansion and poor outcome by adding a 90-second delayed CTA, which may enhance selection of patients who may benefit from hemostatic therapy. © 2014 American Heart Association, Inc.

Urban expansion brought stress to food security in China: Evidence from decreased cropland net primary productivity.

PubMed

He, Chunyang; Liu, Zhifeng; Xu, Min; Ma, Qun; Dou, Yinyin

2017-01-15

Cropland net primary productivity (CNPP) is a crucial indicator of grain productivity and food security. However, assessments of the impact of urban expansion on the CNPP in China have been inadequate owing to data limitations. In this paper, our objective was to assess the impact of urban expansion on the CNPP in China from 1992 to 2015 in a spatially explicit manner. We first obtained the CNPP before urban expansion between 1992 and 2015 in China using the Carnegie-Ames-Stanford Approach (CASA) model. We then assessed the impact of urban expansion on the CNPP from 1992 to 2015 at multiple scales (the whole country, agricultural zones, and urban expansion hotspots) by combining the CNPP before urban expansion with the urban land coverage time series extracted from multi-source remotely sensed data. We found that the total loss of the CNPP due to urban expansion from 1992 to 2015 was 13.77TgC, which accounts for 1.88% of the CNPP before urban expansion in China. This CNPP loss resulted in a 12.45-million-ton decrease in grain production in China, corresponding to a reduction in the mean annual grain self-sufficiency rate of 2%. Therefore, we concluded that rapid urban expansion from 1992 to 2015 caused stress to China's food security. We suggest that it is still vital for China to effectively protect cropland to improve the urbanization level to 60% by 2020. Copyright © 2016 Elsevier B.V. All rights reserved.

Thin-plate spline analysis of treatment effects of rapid maxillary expansion and face mask therapy in early Class III malocclusions.

PubMed

Baccetti, T; Franchi, L; McNamara, J A

1999-06-01

An effective morphometric method (thin-plate spline analysis) was applied to evaluate shape changes in the craniofacial configuration of a sample of 23 children with Class III malocclusions in the early mixed dentition treated with rapid maxillary expansion and face mask therapy, and compared with a sample of 17 children with untreated Class III malocclusions. Significant treatment-induced changes involved both the maxilla and the mandible. Major deformations consisted of forward displacement of the maxillary complex from the pterygoid region and of anterior morphogenetic rotation of the mandible, due to a significant upward and forward direction of growth of the mandibular condyle. Significant differences in size changes due to reduced increments in mandibular dimensions were associated with significant shape changes in the treated group.

The response of the ionosphere to the injection of chemically reactive vapors

NASA Technical Reports Server (NTRS)

Bernhardt, P. A.

1976-01-01

As a gas released in the ionosphere expands, it is rapidly cooled. When the vapor becomes sufficiently tenuous, it is reheated by collisions with the ambient atmosphere and its flow is then governed by diffusive expansion. As the injected gas becomes well mixed with the plasma, a hole is created by chemical processes. In the case of diatomic hydrogen release, depression of the electron concentrations is governed by the charge exchange reaction between oxygen ions and hydrogen, producing positive hydroxyl ions. Hydroxyl ions rapidly react with the electron gas to produce excited oxygen and hydrogen atoms. Enhanced airglow emissions result from the transition of the excited atoms to lower energy states. The electron temperature in the depleted region rises sharply causing a thermal expansion of the plasma and a further reduction in the local plasma concentration.

Accelerated Cartesian expansions for the rapid solution of periodic multiscale problems

DOE PAGES

Baczewski, Andrew David; Dault, Daniel L.; Shanker, Balasubramaniam

2012-07-03

We present an algorithm for the fast and efficient solution of integral equations that arise in the analysis of scattering from periodic arrays of PEC objects, such as multiband frequency selective surfaces (FSS) or metamaterial structures. Our approach relies upon the method of Accelerated Cartesian Expansions (ACE) to rapidly evaluate the requisite potential integrals. ACE is analogous to FMM in that it can be used to accelerate the matrix vector product used in the solution of systems discretized using MoM. Here, ACE provides linear scaling in both CPU time and memory. Details regarding the implementation of this method within themore » context of periodic systems are provided, as well as results that establish error convergence and scalability. In addition, we also demonstrate the applicability of this algorithm by studying several exemplary electrically dense systems.« less

Cone-beam computed tomography evaluation of dentoskeletal changes after asymmetric rapid maxillary expansion.

PubMed

Baka, Zeliha Muge; Akin, Mehmet; Ucar, Faruk Izzet; Ileri, Zehra

2015-01-01

The aims of this study were to quantitatively evaluate the changes in arch widths and buccolingual inclinations of the posterior teeth after asymmetric rapid maxillary expansion (ARME) and to compare the measurements between the crossbite and the noncrossbite sides with cone-beam computed tomography (CBCT). From our clinic archives, we selected the CBCT records of 30 patients with unilateral skeletal crossbite (13 boys, 14.2 ± 1.3 years old; 17 girls, 13.8 ± 1.3 years old) who underwent ARME treatment. A modified acrylic bonded rapid maxillary expansion appliance including an occlusal locking mechanism was used in all patients. CBCT records had been taken before ARME treatment and after a 3-month retention period. Fourteen angular and 80 linear measurements were taken for the maxilla and the mandible. Frontally clipped CBCT images were used for the evaluation. Paired sample and independent sample t tests were used for statistical comparisons. Comparisons of the before-treatment and after-retention measurements showed that the arch widths and buccolingual inclinations of the posterior teeth increased significantly on the crossbite side of the maxilla and on the noncrossbite side of the mandible (P <0.05). Comparison of the 2 sides showed statistically significant differences in both the maxilla and the mandible (P <0.05). After ARME treatment, the crossbite side of the maxilla and the noncrossbite side of the mandible were more affected than were the opposite sides. Copyright © 2015. Published by Elsevier Inc.

Interaction Among Inhomogeneities and Inclusions.

DTIC Science & Technology

1985-01-22

Some Recent Advances, ed. by X. Markenscoff, ASME, AMD, 63 (1984) 59-68. N. Kinoshita and T. Mura, " Eigenstrain Problems in a Finite Rody", SIAM J...terms of the free expansion strain ( eigenstrain ), the elastic moduli of the rock and the solidified demolition agent, and the fracture stress of rock...found an unexpected result for a sliding inclusion. It is found that when an ellipsoidal inclusion undergoes a uniform shear eigenstrain (non- elastic

Technical economics in the power industry

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

Dicks, J.B.

1990-01-01

This paper reports discusses technical economics is an emerging subject different from such areas as engineering management. The subject of engineering economics will be vital in the coming years as the world economy is about to undergo an economic explosion due to the effect of the computer on every area of technology and the simultaneous large expansion of the world market through the opening and democratization of the Communist block together with the European Common Market.

The Influence of Relationship Power Dynamics on HIV Testing in Rural Malawi

PubMed Central

Conroy, Amy A.

2014-01-01

Using the theory of gender and power (TGP) and data from the Tsogolo la Thanzi (TLT) study, we examined how relationship power shapes young people’s decisions to test for HIV in rural Malawi (N=932), a high-HIV prevalence setting undergoing rapid expansions in testing services. We used generalized estimating equations (GEE) to examine associations among five constructs of relationship power (socioeconomic inequalities, relationship dominance, relationship violence, relationship unity, and mistrust), perceived risk, and receiving an HIV test over a 16-month period. The results indicate that young Malawians are testing for HIV at relatively high rates, repeatedly, and not just during pregnancy. Over the study period, 47.3% of respondents received at least one HIV test outside of TLT (range: 0–4). The GEE analysis revealed that men and women with higher levels of relationship unity were less likely to test for HIV. For men, being a victim of sexual coercion was an additional barrier to testing. Women’s testing decisions were more strongly influenced by perceptions of a partner’s risk for HIV than their own, whereas men relied more on self-assessments. The results highlight that testing decisions are deeply embedded within the relationship context, which should be considered in future HIV testing interventions. PMID:24670263

Electrically activated artificial muscles made with liquid crystal elastomers

NASA Astrophysics Data System (ADS)

Shahinpoor, Mohsen

2000-06-01

Composites of monodomain nematic liquid crystal elastomers and a conducting material distributed within their network are shown to exhibit large deformations, i.e. contraction, expansion, bending with strains of over 200% and appreciable force, by Joule heating through electrical activation. The electrical activation of the conducting material induces a rapid Joule heating in the sample leading to a nematic to isotropic phase transition where the elastomer of dimensions 32 mm x 7 mm x 0.4 mm contracted in less than a second. The cooling process, isotropic to nematic transition where the elastomer expands back to its original length, was slow and took 8 seconds. The material studied here is a highly novel liquid crystalline co-elastomer, invented and developed by Heino Finkelmann and co-workers at Albert-Ludwigs-Universitaet in Freiburg, Germany. The material is such that in which the mesogenic units are in both the side chains and the main chains of the elastomer. This co-elastomer was then mechanically loaded to induce a uniaxial network anisotropy before the cross-linking reaction was completed. These samples were then made into a composite with a conducting material such as dispersed silver particles or graphite fibers. The final samples was capable of undergoing more than 200% reversible strain in a few seconds.

Photoaffinity Labeling via Nitrenium Ion Chemistry: Protonation of the Nitrene Derived from a 4-Amino-3-nitrophenylazide to Afford Reactive Nitrenium Ion Pairs

PubMed Central

Voskresenska, Valentyna; Wilson, R. Marshall; Panov, Maxim; Tarnovsky, Alexander N.; Krause, Jeanette A.; Vyas, Shubham; Winter, Arthur H.; Hadad, Christopher M.

2009-01-01

Phenyl azides with powerful electron-donating substituents are known to deviate from the usual photochemical behavior of other phenyl azides. They do not undergo ring expansion, but form basic nitrenes that protonate to form nitrenium ions. The photochemistry of the widely used photoaffinity labeling system 4-amino-3-nitrophenyl azide, 5, has been studied by transient absorption spectroscopy from femtosecond to microsecond time domains and from a theoretical perspective. The nitrene generation from azide 5 occurs on the S2 surface, in violation of Kasha's rule. The resulting nitrene is a powerful base and abstracts protons extremely rapidly from a variety of sources to form a nitrenium ion. In methanol, this protonation occurs in about 5 ps, which is the fastest intermolecular protonation observed to date. Suitable proton sources include alcohols, amine salts, and even acidic C-H bonds such as acetonitrile. The resulting nitrenium ion is stabilized by the electron-donating 4-amino group to afford a diiminoquinone-like species that collapses relatively slowly to form the ultimate cross-linked product. In some cases in which the anion is a good hydride donor, cross-linking is replaced by reduction of the nitrenium ion to the corresponding amine. PMID:19624129

Phase transformations in SrAl2Si2O8 glass

NASA Technical Reports Server (NTRS)

Drummond, Charles H., III; Bansal, Narottam P.

1992-01-01

Bulk glass of SrAl2Si2O8 composition crystallized at temperatures below 1000 C into hexacelsian, a hexagonal phase which undergoes a reversible, rapid transformation to an orthorhombic phase at 758 C, and at higher temperatures crystallized as celsian, a monoclinic phase. The glass transition temperature and crystallization onset temperature were determined to be 883 C and 1086 C, respectively, from DSC at a heating rate of 20 C/min. Thermal expansion of the various phases and density and bend strengths of cold isostatically pressed glass powder bars, sintered at various temperatures, were measured. The kinetics of the hexacelsian-to-celsian transformation for SrAl2Si2O8 were studied. Hexacelsian flakes were isothermally heat treated at temperatures from 1025-1200 C for various times. Avrami plots were determined by quantitatively measuring the amount of monoclinic celsian formed at various times using x ray diffraction. The Avrami constant was determined to be 1.1, suggesting a diffusionless, one dimensional transformation mechanism. The activation energy was determined from an Arrhenius plot of 1n k vs. 1/T to be 125 kilocal/mole. This value is consistent with a mechanism which transforms the layered hexacelsian structure to a three dimensional framework celsian structure and involves the breaking of Si-O bonds.

A Comparison of Dental and Skeletal Changes Between Rapid Palatal Expansion and Nickel Titanium Palatal Expansion

DTIC Science & Technology

1999-11-03

increases in the posterior and anterior implants of 0.42 mm/year and 0,14 mm/year, respectively. Korn •je and Baumrind also found no evidence to...0.23 mm/year, respectively. Also reporting asymmetric growth of the maxilla, Bjork and Skieller,34 and Korn and Baumrind observed posterior midpalatal...Skieller V. Growth in width of the maxilla studied by the implant method. Scand J Plast Reconstr Surg 1974;8:26-33. 35. Korn EL, Baumrind S

Theoretical modelling on thermal expansion of Al, Ag and Cu nanomaterials

NASA Astrophysics Data System (ADS)

Manu, Mehul; Dubey, Vikash

2018-05-01

A simple theoretical model is developed for the calculating the coefficient of volume thermal expansion (CTE) and volume thermal expansion (VTE) of Al, Ag and Cu nanomaterials by considering the cubo-octahedral structure with the change of temperature and the cluster size. At the room temperature, the coefficient of volume thermal expansion decreases sharply below 20-25 nm and the decrement of the coefficient of volume thermal expansion becomes slower above 20-25 nm. We also saw a variation in the volume thermal expansion with the variation of temperature and cluster size. At a fixed cluster size, the volume thermal expansion increases with an increase of temperature at below the melting temperature and show a linear relation of volume thermal expansion with the temperature. At a constant temperature, the volume thermal expansion decreases rapidly with an increase in cluster size below 20-25 nm and after 20-25 nm the decrement of volume thermal expansion becomes slower with the increase of the size of the cluster. Thermal expansion is due to the anharmonicity of the atom interaction. As the temperature rises the amplitude of crystal lattice vibration increases, but the equilibrium distance shifts as the atom spend more time at distance greater than the original spacing due as the repulsion at short distance greater than the corresponding attraction at farther distance. In considering the cubo- octahedral structure with the cluster order, the model prediction on the CTE and the VTE are in good agreement with the available experimental data which demonstrate the validity of our work.

Complement proteins bind to nanoparticle protein corona and undergo dynamic exchange in vivo

NASA Astrophysics Data System (ADS)

Chen, Fangfang; Wang, Guankui; Griffin, James I.; Brenneman, Barbara; Banda, Nirmal K.; Holers, V. Michael; Backos, Donald S.; Wu, Linping; Moghimi, Seyed Moein; Simberg, Dmitri

2017-05-01

When nanoparticles are intravenously injected into the body, complement proteins deposit on the surface of nanoparticles in a process called opsonization. These proteins prime the particle for removal by immune cells and may contribute toward infusion-related adverse effects such as allergic responses. The ways complement proteins assemble on nanoparticles have remained unclear. Here, we show that dextran-coated superparamagnetic iron oxide core-shell nanoworms incubated in human serum and plasma are rapidly opsonized with the third complement component (C3) via the alternative pathway. Serum and plasma proteins bound to the nanoworms are mostly intercalated into the nanoworm shell. We show that C3 covalently binds to these absorbed proteins rather than the dextran shell and the protein-bound C3 undergoes dynamic exchange in vitro. Surface-bound proteins accelerate the assembly of the complement components of the alternative pathway on the nanoworm surface. When nanoworms pre-coated with human plasma were injected into mice, C3 and other adsorbed proteins undergo rapid loss. Our results provide important insight into dynamics of protein adsorption and complement opsonization of nanomedicines.

Mapping ecosystem services for land use planning, the case of Central Kalimantan.

PubMed

Sumarga, Elham; Hein, Lars

2014-07-01

Indonesia is subject to rapid land use change. One of the main causes for the conversion of land is the rapid expansion of the oil palm sector. Land use change involves a progressive loss of forest cover, with major impacts on biodiversity and global CO2 emissions. Ecosystem services have been proposed as a concept that would facilitate the identification of sustainable land management options, however, the scale of land conversion and its spatial diversity pose particular challenges in Indonesia. The objective of this paper is to analyze how ecosystem services can be mapped at the provincial scale, focusing on Central Kalimantan, and to examine how ecosystem services maps can be used for a land use planning. Central Kalimantan is subject to rapid deforestation including the loss of peatland forests and the provincial still lacks a comprehensive land use plan. We examine how seven key ecosystem services can be mapped and modeled at the provincial scale, using a variety of models, and how large scale ecosystem services maps can support the identification of options for sustainable expansion of palm oil production.

Laparoscopic appendectomy to remove a metallic foreign body in a wild Bornean orangutan (Pongo pygmaeus) undergoing rehabilitation.

PubMed

Llano Sanchez, Karmele; Handayani, Ayu B; Nelson, Christine L; Eng, Jaclyn W L; Prameswari, Wendi; Hicks, Nigel; Pizzi, Romain

2016-12-01

A laparoscopic appendectomy was performed in a wild orangutan (Pongo pygmaeus) undergoing rehabilitation, for a metal nail found on radiographs, using 3-mm instrumentation. Post-operative healing was rapid and uneventful, with return to the forest within 10 days. This is the first report of minimally invasive surgery in a wild orangutan. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Role of Dioxin Receptor in Mammary Development and Carcinogenesis

DTIC Science & Technology

2006-06-01

hydrocarbons: Examination of the mechanism of toxicity. Annu. Rev. Pharmacol. Toxicol. 22: 517-554. 2. Giannone JV, Okey AB, Harper PA (1995...transcriptional activation, the liganded hR undergoes a rapid degradation leading to a massive epletion both in vivo and in vitro ( Giannone et al., 998...and undergoes a massive depletion within hours of ligand binding ( Giannone et al., 1998; Harper et al., 1994; Prokipcak and Okey, 1991; Pollenz, 1996

Alkali-aggregate reaction under the influence of deicing salts in the Hokuriku district, Japan

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

Katayama, Tetsuya; Tagami, Masahiko; Sarai, Yoshinori

2004-11-15

Concrete cores taken from highway bridges and culverts undergoing alkali-silica reaction (ASR) were investigated petrographically by means of core scanning, point counting, polarizing microscopy, scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), electron-probe microanalysis with energy-dispersive spectrometry, in conjunction with wet chemical analyses and expansion tests. Field damage was roughly proportional to the content of andesite in the gravel aggregates due to the presence of highly reactive cristobalite and tridymite. Electron-probe microanalyzer analysis of unhydrated cement phases in the concrete revealed that the cement used had contained at least 0.5% to 1.0% alkali (Na{sub 2}Oeq) and that both the aggregatesmore » and the deicing salts had supplied part of the water-soluble alkali to concrete toward the threshold of producing ASR (Na{sub 2}O{sub eq} 3.0 kg/m{sup 3}). An accelerated concrete core expansion test (1 M NaOH, 80 deg. C) of the damaged structures mostly gave core expansions of >0.10% at 21 days (or >0.05% at 14 days), nearly comparable to those of a slow expansion test with saturated NaCl solution (50 deg. C, 91 days) which produced Cl-containing ASR gel.« less

A role for intermediate radial glia in the tangential expansion of the mammalian cerebral cortex.

PubMed

Reillo, Isabel; de Juan Romero, Camino; García-Cabezas, Miguel Ángel; Borrell, Víctor

2011-07-01

The cerebral cortex of large mammals undergoes massive surface area expansion and folding during development. Specific mechanisms to orchestrate the growth of the cortex in surface area rather than in thickness are likely to exist, but they have not been identified. Analyzing multiple species, we have identified a specialized type of progenitor cell that is exclusive to mammals with a folded cerebral cortex, which we named intermediate radial glia cell (IRGC). IRGCs express Pax6 but not Tbr2, have a radial fiber contacting the pial surface but not the ventricular surface, and are found in both the inner subventricular zone and outer subventricular zone (OSVZ). We find that IRGCs are massively generated in the OSVZ, thus augmenting the numbers of radial fibers. Fanning out of this expanding radial fiber scaffold promotes the tangential dispersion of radially migrating neurons, allowing for the growth in surface area of the cortical sheet. Accordingly, the tangential expansion of particular cortical regions was preceded by high proliferation in the underlying OSVZ, whereas the experimental reduction of IRGCs impaired the tangential dispersion of neurons and resulted in a smaller cortical surface. Thus, the generation of IRGCs plays a key role in the tangential expansion of the mammalian cerebral cortex.

Retention period after treatment of posterior crossbite with maxillary expansion: a systematic review.

PubMed

Costa, Julia Garcia; Galindo, Thaís Magalhães; Mattos, Claudia Trindade; Cury-Saramago, Adriana de Alcantara

2017-01-01

The aim of this systematic review was to evaluate the duration of the retention period in growing patients undergoing maxillary expansion and its relation with posterior crossbite stability. Search strategies were executed for electronic databases Cochrane Library, Web of Science, PubMed and Scopus, which were completed on January 15, 2016. The inclusion criteria included randomized, prospective or retrospective controlled trials in growing subjects with posterior crossbite; treated with maxillary expanders; retention phase after expansion; post-retention phase of at least 6 months. The exclusion criteria were anterior crossbite, craniofacial anomalies, surgery or another orthodontic intervention; case reports; author's opinions articles, thesis, literature reviews and systematic reviews. The risk of bias of selected articles was assessed with Cochrane risk of bias tool for RCTs and Downs and Black checklist for non-RCTs. A total of 156 titles/abstracts was retrieved, 44 full-texts were examined, and 6 articles were selected and assessed for their methodological quality. The retention period after maxillary expansion ranged between 4 weeks and 16 months. Fixed (acrylic plate, Haas, Hyrax and quad-helix) or removable (Hawley and Hawley expander) appliances were used for retention. Six months of retention with either fixed or removable appliances seem to be enough to avoid relapse or to guarantee minimal changes in a short-term follow-up.

Recent dynamics of alpine lakes on the endorheic Changtang Plateau from multi-mission satellite data

NASA Astrophysics Data System (ADS)

Yang, Kehan; Yao, Fangfang; Wang, Jida; Luo, Jiancheng; Shen, Zhanfeng; Wang, Chao; Song, Chunqiao

2017-09-01

Monitoring of the alpine lakes on the endorheic Changtang Plateau is vitally important in understanding climate impacts on hydrological cycle. Existing studies have revealed an accelerated lake expansion on the Changtang Plateau during the 2000s compared with prior decades. However, the partial hiatus of recent Landsat archive affected the continuation of understanding the lake changes in the recent decade. Here we synergistically used imagery from Landsat and Huanjing satellites to enable a detailed monitoring of lake area dynamics on the Changtang Plateau. Our results present that lakes on the Changtang Plateau continued to expand at a rapid rate of 340.79 km2 yr-1 (1.06% yr-1, p < 0.05) from 2009 to 2014. Changes in endorheic (terminal) lakes contribute to 98% of the net expansion, suggesting that monitoring endorheic lake dynamics is of critical importance for understanding climate changes. Meanwhile, changes in saline lakes, which are mostly endorheic, account for 96% of the net expansion, implying that the proportion of freshwater storage on the Changtang Plateau is likely in decline. Rapid expansion occurred in both glacier-fed and non-glacier-fed lakes, with a rate of 224.94 km2 yr-1 (0.92% yr-1, p < 0.05) and 115.85 km2 yr-1 (1.47% yr-1, p = 0.08), respectively, indicating that glacier retreat alone may not fully explain the recent lake expansion. Intra-annual variations of the selected 24 large lakes fluctuated within 0.22-2.46% (in coefficient of variation) for glacier-fed lakes and 0.17-2.36% for non-glacier-fed lakes. Most of these lakes expanded during the unfrozen period (from May/June to October) and reached to their maximum extents in September or October. By spatially associating our revealed lake changes with climate variables, we observed that the recent lake expansion is more related to precipitation than to temperature, although future efforts are needed for a more comprehensive picture of the lake changing mechanisms.

[Built-up land change and its impact on ecological quality in a fast-growing economic zone: Jinjiang County, Fujian Province, China].

PubMed

Shi, Ting Ting; Xu, Han Qiu; Tang, Fei

2017-04-18

Since China's reform and opening-up, the rapid growth of China's economy has greatly accelerated the expansion of built-up land, which has affected regional ecological environment to a great extent. Taking Jinjiang County of Fujian Province, one of the fastest economic-developing counties in the coastal areas of southeastern China, as a case study area, this paper focused on analyzing the rapid built-up land expansion process of the county and its impact on county's ecological quality using remote sensing techniques. Based on two Landsat images of 1996 and 2015 of Jinjiang, the built-up land of the county was extracted using the index-based built-up index (IBI) and its change was analyzed. In the meantime, the ecological status of Jinjiang was evaluated with a recently-proposed remote sensing based ecological index (RSEI) and the relationship between the built-up land dynamics and the ecological status changes of the county was quantitatively examined. The results showed that during the period from 1996 to 2015, the area of built-up land of Jinjiang had a net increase of 68.54 km 2 , a growth of 45%, and the expansion intensity was 0.55. The expansion of the built-up lands has caused overall degradation of the county's ecological quality. The mean value of RSEI of the county had declined from 0.532 in 1996 to 0.460 in 2015, a drop of13.5%. The area proportion of high ecological-quality grades also significantly fell from 39% in 1996 to 21% in 2015. The built-up land expansion intensity was negatively correlated with the ecological quality change.

Carbohydrate production, balance and translocation in leaves, shoots and fruits of Montmorency sour cherry

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

Kappes, E.M.

1986-01-01

Carbohydrate production, export and use were studied for different organs of sour cherry (Prunus cerasus L. Montmorency). Gross carbohydrate (/sup 14/CO/sub 2/) export started between 27.2 and 77.6% of full leaf expansion. The 10th leaf developing started export later than the 7th leaf, suggesting that higher carbohydrate availability during leaf expansion delays export initiation. In support of this, gross export started earlier (44.4-52.4% full expansion) after source leaf removal, than in the control (77.6%). Translocation was primarily vertical (following orthostichies). Most leaves of fruiting shoots exported bidirectionally to the apex and fruits, only leaves closest to fruits exported exclusively tomore » fruits during rapid cell division (Stage I) and rapid cell expansion (Stage III). Net export, determined from carbohydrate balance models started at 17 and 51% expansion for the 7th and terminal leaf, and at 26.5% of shoot elongation. Cumulative carbohydrate production of the 7th and terminal leaves during the first 9 and 11 days after emergence, exceeded carbohydrate accumulated at final size, 464.2 and 148.9 mg. A fruit carbohydrate balance was developed to determine contributions by fruit photosynthesis and fruit respiration, and to identify periods of greatest carbohydrate import. Fruit photosynthesis during development was characterized under different environmental conditions. Gross photosynthesis and chlorophyll content per fruit increased to a maximum during stage II and decreased thereafter. Gross photosynthesis approached a maximum at 40/sub 0/C. Since dark respiration increased exponentially over the same temperature range, net photosynthesis reached a maximum at 18/sup 0/C. Photorespiration was not detected.« less

Thin-plate spline analysis of the short- and long-term effects of rapid maxillary expansion.

PubMed

Franchi, Lorenzo; Baccetti, Tiziano; Cameron, Christopher G; Kutcipal, Elizabeth A; McNamara, James A

2002-04-01

The aim of this study was to investigate the short- and long-term effects induced by rapid maxillary expansion (RME) on the shape of the maxillary and circummaxillary structures by means of thin-plate spline (TPS) analysis. The sample consisted of 42 patients who were compared with a control sample of 20 subjects. The treated subjects underwent Haas-type RME, followed by fixed appliance therapy. Postero-anterior (PA) cephalograms were analysed for each treated subject at T1 (pre-treatment), T2 (immediate post-expansion), and T3 (long-term observation), and were available at T1 and T3 for the control group (CG). The mean age at T1 was 11 years and 10 months for both groups. The mean chronological ages at T3 were 20 years, 6 months for the treated group (TG) and 17 years, 8 months for the control group. The study focused on shape changes in the maxillary, nasal, zygomatic, and orbital regions. TPS analysis revealed significant shape changes in the TG. They consisted of an upward and lateral displacement of the two halves of the naso-maxillary complex as a result of active expansion in the short-term, and normalization of maxillary shape in the transverse dimension in the long-term (the initial transverse deficiency of the maxilla in the treated group was eliminated by RME therapy both in the short- and long-term). At the end of the observation period, the nasal cavities were larger when compared with both their pre-expansion configuration and the final configuration in the controls. RME with the Haas appliance appears to be an efficient therapeutic means to induce permanent favourable changes in the shape of the naso-maxillary complex.

Growth Type and Functional Trajectories: An Empirical Study of Urban Expansion in Nanjing, China

PubMed Central

Yuan, Feng

2016-01-01

Drawing upon the Landsat satellite images of Nanjing from 1985, 1995, 2001, 2007, and 2013, this paper integrates the convex hull analysis and common edge analysis at double scales, and develops a comprehensive matrix analysis to distinguish the different types of urban land expansion. The results show that Nanjing experienced rapid urban expansion, dominated by a mix of residential and manufacturing land from 1985 to 2013, which in turn has promoted Nanjing’s shift from a compact mononuclear city to a polycentric one. Spatial patterns of three specific types of growth, namely infilling, extension, and enclave were quite different in four consecutive periods. These patterns result primarily from the existing topographic constraints, as well as government-oriented urban planning and policies. By intersecting the function maps, we also reveal the functional evolution of newly-developed urban land. Moreover, both self-enhancing and mutual promotion of the newly developed functions are surveyed over the last decade. Our study confirms that the integration of a multi-scale method and multi-perspective analysis, such as the spatiotemporal patterns and functional evolution, helps us to better understand the rapid urban growth in China. PMID:26845155

Seed bank characteristics of the Nymphoides peltata population in Lake Taihu

NASA Astrophysics Data System (ADS)

Huang, Wei; Chen, Qiuwen; Chen, Kaining

2015-08-01

The Nymphoides peltata (N. peltata) population has shown rapid expansion in Lake Taihu, China, in recent years. The core question is whether N. peltata seeds have contributed to the expansion. To address this, we randomly selected three N. peltata stands to investigate the seed bank characteristics of N. peltata in Lake Taihu. Results showed that N. peltata had high seed production, with a maximum seed yield of 1763 seeds per m2. Density of intact and fragmented seeds decreased rapidly with sediment depth. Few intact or fragmented seeds were distributed at depths greater than 4 cm in the sediment. Spatial distribution of the seed bank indicated that most seeds sank to the sediment within the N. peltata stands, and few seeds took advantage of their floating ability. Seeds recovered from the sediment during April to June had a low germination rate, and no seeds germinated during October to April. Cold exposure treatment increased the germination rate remarkably. No seedlings were found in the field from January 2012 to December 2012, indicating that few seeds were successfully established in the surveyed area. The results suggested that sexual reproduction had little direct contribution to the N. peltata expansion in this large shallow lake.

Changes in nasal volume after surgically assisted bone-borne rapid maxillary expansion.

PubMed

Deeb, Wayel; Hansen, Lars; Hotan, Thorsten; Hietschold, Volker; Harzer, Winfried; Tausche, Eve

2010-06-01

The purposes of this study were to detect, locate, and examine the changes in transverse nasal width, area, and volume from bone-borne, surgically assisted rapid maxillary expansion (SARME) with the Dresden distractor by using computer tomography (CT). Sixteen patients (average age, 28.7 years) underwent axial CT scanning before and 6 months after SARME. They also underwent CT fusion on specific bony structures. The nasal bone width was examined in the coronal plane. The cross-sectional images of the nasal cavity were taken of the area surrounding the apertura piriformis, the choanae, and in between. We calculated cross-sectional areas and nasal volume according to these data. All but 2 patients had an increase in nasal volume of at least 5.1% (SD, 4.6%). The largest value of 35.3% (SD, 45.8%) was measured anteriorly on the nasal floor, decreasing cranially and posteriorly. This correlated with the V-shaped opening of the sutura palatina. There was no significant correlation between increase in nasal volume and transversal expansion. Because most of the air we breathe passes over the lower nasal floor, SARME is likely to improve nasal breathing. 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

A rapid-exchange monorail stent system for salvage of failing femoropopliteal bypass grafts.

PubMed

Jahnke, Thomas; Brossmann, Joachim; Walluscheck, Knut; Heller, Martin; Müller-Hülsbeck, Stefan

2003-08-01

To analyze the safety and effectiveness of a new monorail stent system for the treatment of failing femoropopliteal bypass grafts. Acute distal occlusions or stenoses of femoropopliteal bypass grafts were treated with balloon-expandable stents (13 or 18-mm diameter) pre-mounted on a monorail balloon catheter system. The delivery system was assessed subjectively for (1). compatibility with the sheath, (2). lesion crossing potential, (3). radiopacity, (4). flexibility of the catheter, (5). adequacy of stent expansion, and (5). balloon refolding. In 8 failing bypass grafts with distal lesions, the delivery system successfully deployed the stent at the desired location. Sheath compatibility, catheter flexibility, lesion crossing, and stent expansion were rated "excellent" by all examiners for the 18-mm device. Radiopacity of the mounted stent was graded "good" before and during positioning, but only "sufficient" following expansion. For this type of lesion, the investigators rated the overall performance of the device superior to conventional "over-the-wire" systems. The monorail balloon-expandable stent delivery system provides rapid introduction of the device over the guidewire, and its low profile facilitates the use of small sheaths to minimize access-site complications.

The palm oil supply chain, deforestation and peat clearing

NASA Astrophysics Data System (ADS)

Boucher, D. H.

2013-12-01

The palm oil industry has expanded rapidly in the last two decades, particularly in Indonesia. A considerable amount of this expansion has been at the expense of forests and peatlands, resulting in considerable greenhouse gas emissions. Now the industry is faced with two new challenges. There is a possible oversupply on the global market due to recent expansion and the time lag between clearing and new production coming on line, which may depress prices considerably. Furthermore, there is increasing pressure to reduce the industry's impact on climate and biodiversity, exemplified by the commitment by the businesses of the Consumer Goods Forum to eliminate deforestation from their supply chains by 2020. This presentation will examine the interaction between these two challenges and its implications for the industry, in both southeast Asia and new regions of expansion, and how this interaction could transform the industry's mode of expansion in the coming decade.

Human expansion precipitates niche expansion for an opportunistic apex predator (Puma concolor).

PubMed

Moss, Wynne E; Alldredge, Mathew W; Logan, Kenneth A; Pauli, Jonathan N

2016-12-23

There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation. Yet, little is known about processes regulating these novel ecosystems, or behaviours employed by species adapting to them. We evaluated the isotopic niche of an apex carnivore, the cougar (Puma concolor), over broad spatiotemporal scales and in a region characterized by rapid landscape change. We detected a shift in resource use, from near complete specialization on native herbivores in wildlands to greater use of exotic and invasive species by cougars in contemporary urban interfaces. We show that 25 years ago, cougars inhabiting these same urban interfaces possessed diets that were intermediate. Thus, niche expansion followed human expansion over both time and space, indicating that an important top predator is interacting with prey in novel ways. Thus, though human-dominated landscapes can provide sufficient resources for apex carnivores, they do not necessarily preserve their ecological relationships.

Hadronic expansion dynamics in central Pb+Pb collisions at 158 GeV per nucleon

DOE PAGES

Appelshäuser, H.

1998-03-24

Two-particle correlation functions of negative hadrons over wide phase space, and transverse mass spectra of negative hadrons and deuterons near mid-rapidity have been measured in central Pb+Pb collisions at 158 GeV per nucleon by the NA49 experiment at the CERN SPS. A novel Coulomb correction procedure for the negative two-particle correlations is employed making use of the measured oppositely charged particle correlation. Within an expanding source scenario these results are used to extract the dynamic characteristics of the hadronic source, resolving the ambiguities between the temperature and transverse expansion velocity of the source, that are unavoidable when single and twomore » particle spectra are analysed separately. Lastly, the source shape, the total duration of the source expansion, the duration of particle emission, the freeze-out temperature and the longitudinal and transverse expansion velocities are deduced.« less

Theory for substorms triggered by sudden reductions in convection

NASA Technical Reports Server (NTRS)

Lyons, L. R.

1996-01-01

Many substorm expansions are triggered by interplanetary magnetic field changes that reduce magnetospheric convection. This suggests that expansion onsets are a result of a reduction in the large-scale electric field imparted to the magnetosphere from the solar wind. Such a reduction disrupts the inward motion and energization of plasma sheet particles that occur during the growth phase. It is proposed that the resulting magnetic drift of particles and a large dawn to dusk gradient in the ion energies leads to a longitudinally localized reduction in the plasma pressure, and thus, to the current wedge formation. This theory accounts for the rapid development of the expansion phase relative to growth phase, the magnitude of the wedge currents, the speeds of tailward and westward expansion of the current reduction region in the equatorial plane, and the speeds of the poleward and westward motion of active aurora in the ionosphere.

Balancing urban growth and ecological conservation: A challenge for planning and governance in China.

PubMed

Güneralp, Burak; Perlstein, Andrew S; Seto, Karen C

2015-10-01

China has high biodiversity and is rapidly urbanizing. However, there is limited understanding of how urban expansion in the country is likely to affect its habitats and biodiversity. In this study, we examine urban expansion patterns and their likely impacts on biodiversity in China by 2030. Our analysis shows that most provinces are expected to experience urban expansion either near their protected areas or in biodiversity hotspots. In a few provinces such as Guangdong in the south, urban expansion is likely to impinge on both protected areas and biodiversity hotspots. We show that policies that could facilitate the integration of natural resource protection into urban planning exist on paper, but the prevailing incentives and institutional arrangements between the central and local governments prevent this kind of integration. Removing these obstacles will be necessary in order to safeguard the country's rich biodiversity in light of the scale of urbanization underway.

Use of Propofol for Induction and Maintenance of Anesthesia in a King Penguin ( Aptenodytes patagonicus ) Undergoing Magnetic Resonance Imaging.

PubMed

Bigby, Sarah E; Carter, Jennifer E; Bauquier, Sébastien; Beths, Thierry

2016-09-01

Anesthesia protocols for patients with intracranial lesions need to provide hemodynamic stability, preserve cerebrovascular autoregulation, avoid increases in intracranial pressure, and facilitate a rapid recovery. Propofol total intravenous anesthesia (TIVA) maintains cerebral blood flow autoregulation and is considered superior to inhalant agents as an anesthetic protocol for patients with intracranial lesions. A propofol-based TIVA subsequent to premedication with medetomidine and diazepam was used in a king penguin ( Aptenodytes patagonicus ) undergoing magnetic resonance imaging of the brain after a new onset of seizures. This protocol provided a rapid and smooth induction and calm recovery in the penguin. When ventilation control is possible, propofol TIVA may be a superior choice to inhalant agents for anesthesia of birds with potential intracranial lesions.

PPARγ ligand production is tightly linked to clonal expansion during initiation of adipocyte differentiation[S

PubMed Central

Hallenborg, Philip; Petersen, Rasmus Koefoed; Feddersen, Søren; Sundekilde, Ulrik; Hansen, Jacob B.; Blagoev, Blagoy; Madsen, Lise; Kristiansen, Karsten

2014-01-01

Adipocyte differentiation is orchestrated by the ligand-activated nuclear receptor PPARγ. Endogenous ligands comprise oxidized derivatives of arachidonic acid and structurally similar PUFAs. Although expression of PPARγ peaks in mature adipocytes, ligands are produced primarily at the onset of differentiation. Concomitant with agonist production, murine fibroblasts undergo two rounds of mitosis referred to as mitotic clonal expansion. Here we show that mouse embryonic fibroblasts deficient in either of two cell cycle inhibitors, the transcription factor p53 or its target gene encoding the cyclin-dependent kinase inhibitor p21, exhibit increased adipogenic potential. The antiadipogenic effect of p53 relied on its transcriptional activity and p21 expression but was circumvented by administration of an exogenous PPARγ agonist suggesting a linkage between cell cycling and PPARγ ligand production. Indeed, cell cycle inhibitory compounds decreased PPARγ ligand production in differentiating 3T3-L1 preadipocytes. Furthermore, these inhibitors abolished the release of arachidonic acid induced by the hormonal cocktail initiating adipogenesis. Collectively, our results suggest that murine fibroblasts require clonal expansion for PPARγ ligand production at the onset of adipocyte differentiation. PMID:25312885

A current disruption mechanism in the neutral sheet - A possible trigger for substorm expansions

NASA Technical Reports Server (NTRS)

Lui, A. T. Y.; Mankofsky, A.; Chang, C.-L.; Papadopoulos, K.; Wu, C. S.

1990-01-01

A linear analysis is performed to investigate the kinetic cross-field streaming instability in the earth's magnetotail neutral sheet region. Numerical solution of the dispersion equation shows that the instability can occur under conditions expected for the neutral sheet just prior to the onset of substorm expansion. The excited waves are obliquely propagating whistlers with a mixed polarization in the lower hybrid frequency range. The ensuing turbulence of this instability can lead to a local reduction of the cross-tail current causing it to continue through the ionosphere to form a substorm current wedge. A substorm expansion onset scenario is proposed based on this instability in which the relative drift between ions and electrons is primarily due to unmagnetized ions undergoing current sheet acceleration in the presence of a cross-tail electric field. The required electric field strength is within the range of electric field values detected in the neutral sheet region during substorm intervals. The skew in local time of substorm onset location and the three conditions under which substorm onset is observed can be understood on the basis of the proposed scenario.

Thermodynamic Behavior of Nano-sized Gold Clusters on the (001) Surface

NASA Technical Reports Server (NTRS)

Paik, Sun M.; Yoo, Sung M.; Namkung, Min; Wincheski, Russell A.; Bushnell, Dennis M. (Technical Monitor)

2001-01-01

We have studied thermal expansion of the surface layers of the hexagonally reconstructed Au (001) surface using a classical Molecular Dynamics (MD) simulation technique with an Embedded Atomic Method (EAM) type many-body potential. We find that the top-most hexagonal layer contracts as temperature increases, whereas the second layer expands or contracts depending on the system size. The magnitude of expansion coefficient of the top layer is much larger than that of the other layers. The calculated thermal expansion coefficients of the top-most layer are about -4.93 x 10(exp -5)Angstroms/Kelvin for the (262 x 227)Angstrom cluster and -3.05 x 10(exp -5)Angstroms/Kelvin for (101 x 87)Angstrom cluster. The Fast Fourier Transform (FFT) image of the atomic density shows that there exists a rotated domain of the top-most hexagonal cluster with rotation angle close to 1 degree at temperature T less than 1000Kelvin. As the temperature increases this domain undergoes a surface orientational phase transition. These predictions are in good agreement with previous phenomenological theories and experimental studies.

Uncovering the Role of Hypermethylation by CTG Expansion in Myotonic Dystrophy Type 1 Using Mutant Human Embryonic Stem Cells.

PubMed

Yanovsky-Dagan, Shira; Avitzour, Michal; Altarescu, Gheona; Renbaum, Paul; Eldar-Geva, Talia; Schonberger, Oshrat; Mitrani-Rosenbaum, Stella; Levy-Lahad, Ephrat; Birnbaum, Ramon Y; Gepstein, Lior; Epsztejn-Litman, Silvina; Eiges, Rachel

2015-08-11

CTG repeat expansion in DMPK, the cause of myotonic dystrophy type 1 (DM1), frequently results in hypermethylation and reduced SIX5 expression. The contribution of hypermethylation to disease pathogenesis and the precise mechanism by which SIX5 expression is reduced are unknown. Using 14 different DM1-affected human embryonic stem cell (hESC) lines, we characterized a differentially methylated region (DMR) near the CTGs. This DMR undergoes hypermethylation as a function of expansion size in a way that is specific to undifferentiated cells and is associated with reduced SIX5 expression. Using functional assays, we provide evidence for regulatory activity of the DMR, which is lost by hypermethylation and may contribute to DM1 pathogenesis by causing SIX5 haplo-insufficiency. This study highlights the power of hESCs in disease modeling and describes a DMR that functions both as an exon coding sequence and as a regulatory element whose activity is epigenetically hampered by a heritable mutation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Spontaneous apoptotic DNA fragmentation in cultured guinea pig gastric mucosal cells.

PubMed

Tsutsumi, S; Rokutan, K; Tsuchiya, T; Mizushima, T

2000-02-01

The purpose of this study was to elucidate the mechanism of spontaneous and rapid cell death of cultured gastric pit cells. Gastric pit cells have a rapid cell turnover rate in vivo. We here show that guinea pig gastric pit cells in culture undergo spontaneous and rapid apoptotic DNA fragmentation, which may represent the rapid cell turnover cycle of gastric pit cells in vivo. This spontaneous apoptotic DNA fragmentation required the presence of fetal calf serum in the culture media. Furthermore, the spontaneous apoptotic DNA fragmentation was prevented by protein synthesis and caspase inhibitors.

Short-term expansion of glacial lakes in the Himalayas

NASA Astrophysics Data System (ADS)

Nagai, H.; Tadono, T.

2017-12-01

A glacial lake outburst flood (GLOF) is a serious mountainous hazard that is related to glacial shrinkage. Despite technical developments in satellite-based lake expansion monitoring, small glacial lakes were collapsed in Bhutan in June 2015 and in Nepal in May 2017. Relatively heavy rainfall was reported downstream just before the floods. Does a large amount of short-term precipitation have a possibility of triggering a GLOF? To answer this question, the temporal change in the glacial lake area is assessed by means of satellite-based synthetic aperture radar, coupled with satellite-derived spatial and temporal distribution of precipitation to evaluate the contribution of rainfall in glacial lake expansion. The Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) observed the Mande Chu river basin in central Bhutan on Aug 11, 2016. Glacial lakes were manually delineated from the orthorectified backscatter amplitude image. They were compared with those delineated from the old satellite images of ALOS ( 2011), PALSAR-2 (2014-2016), and Landsat-8 (2016). The temporal and spatial distributions of precipitation (2010-2016) are obtained from the Global Satellite Mapping of Precipitation (GSMaP) data (10-km spatial / 60-min. temporal resolutions), calibrated by in situ rain gauges (GSMap_RNL/MVL). The outlines of 11 glacial lakes in the study site were successfully traced from 2011 to 2016; rapid expansion was recorded especially in the period between March and July 2016. In this period, exceeding 500 mm of the total amount of precipitation is recorded by GSMaP, whereas the mean precipitation amount is 300-400 mm in the previous years. This implies that relatively larger precipitation occurred in 2016, which is related to the short-term expansion of the glacial lakes. The rapid expansion of smaller lakes can be explained by their relatively shallow depths, which is sensitive to the increase in inflow water volume. This study highlights the importance of high-resolution, frequent observation of small glacial lakes that can expand, possibly corresponding to heavy rainfall, whereas most previous studies focused on large glacial lakes expanding at annual scales. Extreme precipitation should be considered as one of the factors responsible for glacial lake expansion as well as glacier melt.

Rgs13 constrains early B cell responses and limits germinal center sizes.

PubMed

Hwang, Il-Young; Hwang, Kyung-Sun; Park, Chung; Harrison, Kathleen A; Kehrl, John H

2013-01-01

Germinal centers (GCs) are microanatomic structures that develop in secondary lymphoid organs in response to antigenic stimulation. Within GCs B cells clonally expand and their immunoglobulin genes undergo class switch recombination and somatic hypermutation. Transcriptional profiling has identified a number of genes that are prominently expressed in GC B cells. Among them is Rgs13, which encodes an RGS protein with a dual function. Its canonical function is to accelerate the intrinsic GTPase activity of heterotrimeric G-protein α subunits at the plasma membrane, thereby limiting heterotrimeric G-protein signaling. A unique, non-canonical function of RGS13 occurs following translocation to the nucleus, where it represses CREB transcriptional activity. The functional role of RGS13 in GC B cells is unknown. To create a surrogate marker for Rgs13 expression and a loss of function mutation, we inserted a GFP coding region into the Rgs13 genomic locus. Following immunization GFP expression rapidly increased in activated B cells, persisted in GC B cells, but declined in newly generated memory B and plasma cells. Intravital microscopy of the inguinal lymph node (LN) of immunized mice revealed the rapid appearance of GFP(+) cells at LN interfollicular regions and along the T/B cell borders, and eventually within GCs. Analysis of WT, knock-in, and mixed chimeric mice indicated that RGS13 constrains extra-follicular plasma cell generation, GC size, and GC B cell numbers. Analysis of select cell cycle and GC specific genes disclosed an aberrant gene expression profile in the Rgs13 deficient GC B cells. These results indicate that RGS13, likely acting at cell membranes and in nuclei, helps coordinate key decision points during the expansion and differentiation of naive B cells.

Epidemiology of Cystic Fibrosis.

PubMed

Spoonhower, Kimberly A; Davis, Pamela B

2016-03-01

Improved quality of care and rapidly emerging therapeutic strategies to restore chloride transport profoundly impact the epidemiology and pathobiology of cystic fibrosis (CF) in the twenty-first century. CF now serves as a model for chronic illness management, continuous quality improvement via registry data, and a seamless link between basic science research, translational studies, clinical trials, and outcomes research to enable rapid expansion of treatment options. Copyright © 2016 Elsevier Inc. All rights reserved.

Characterization of an FTLD-PDB family with the coexistence of SQSTM1 mutation and hexanucleotide (G₄C₂) repeat expansion in C9orf72 gene.

PubMed

Almeida, Maria Rosário; Letra, Liliana; Pires, Paula; Santos, Ana; Rebelo, Olinda; Guerreiro, Rita; van der Zee, Julie; Van Broeckhoven, Christine; Santana, Isabel

2016-04-01

The C9orf72 expansion is considered a major genetic cause of familial frontotemporal dementia (FTD) in several patients' cohorts. Interestingly, C9orf72 expansion carriers, present also abundant neuronal p62-positive inclusions. Although p62/SQSTM1 mutations were initially associated with Paget disease of bone (PDB), they have been also identified in FTD. We describe an FTD-PDB family in which the proband presented with behavioral FTD phenotype and concomitant Paget disease. The molecular genetic analysis revealed the co-occurrence of 2 mutations; the pathogenic C9orf72 expansion and p.P392L heterozygous missense mutation in SQSTM1 gene. Amongst the 6 family members analyzed, the p.P392L SQSTM1 mutation segregated as expected with PDB, whereas the C9orf72 expansion segregated with frontal cognitive impairment or dementia in all but one carrier. The coexistence of these conditions could be underestimated since neither patients with FTD nor patients with PDB undergo bone scintigraphy or cognitive assessment, respectively. The number of cases with double mutations could also be over looked as the molecular strategy adopted in most laboratories ends with the identification of one pathogenic mutation in one of the known causative genes. Therefore, we advocate for further clinical and molecular evaluation in suspect cases. Copyright © 2016 Elsevier Inc. All rights reserved.

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools.

PubMed

Seto, Karen C; Güneralp, Burak; Hutyra, Lucy R

2012-10-02

Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass. If current trends in population density continue and all areas with high probabilities of urban expansion undergo change, then by 2030, urban land cover will increase by 1.2 million km(2), nearly tripling the global urban land area circa 2000. This increase would result in considerable loss of habitats in key biodiversity hotspots, with the highest rates of forecasted urban growth to take place in regions that were relatively undisturbed by urban development in 2000: the Eastern Afromontane, the Guinean Forests of West Africa, and the Western Ghats and Sri Lanka hotspots. Within the pan-tropics, loss in vegetation biomass from areas with high probability of urban expansion is estimated to be 1.38 PgC (0.05 PgC yr(-1)), equal to ∼5% of emissions from tropical deforestation and land-use change. Although urbanization is often considered a local issue, the aggregate global impacts of projected urban expansion will require significant policy changes to affect future growth trajectories to minimize global biodiversity and vegetation carbon losses.

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools

PubMed Central

Seto, Karen C.; Güneralp, Burak; Hutyra, Lucy R.

2012-01-01

Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass. If current trends in population density continue and all areas with high probabilities of urban expansion undergo change, then by 2030, urban land cover will increase by 1.2 million km2, nearly tripling the global urban land area circa 2000. This increase would result in considerable loss of habitats in key biodiversity hotspots, with the highest rates of forecasted urban growth to take place in regions that were relatively undisturbed by urban development in 2000: the Eastern Afromontane, the Guinean Forests of West Africa, and the Western Ghats and Sri Lanka hotspots. Within the pan-tropics, loss in vegetation biomass from areas with high probability of urban expansion is estimated to be 1.38 PgC (0.05 PgC yr−1), equal to ∼5% of emissions from tropical deforestation and land-use change. Although urbanization is often considered a local issue, the aggregate global impacts of projected urban expansion will require significant policy changes to affect future growth trajectories to minimize global biodiversity and vegetation carbon losses. PMID:22988086

Anchorage onto deciduous teeth: effectiveness of early rapid maxillary expansion in increasing dental arch dimension and improving anterior crowding.

PubMed

Mutinelli, Sabrina; Manfredi, Mario; Guiducci, Antonio; Denotti, Gloria; Cozzani, Mauro

2015-01-01

Anchorage onto permanent dentition is a common procedure in rapid maxillary expansion. However, replacing first permanent molars with the second deciduous molars seems to be an option to reduce some negative side effects during orthodontic treatment. The purpose of this study was to evaluate the dental effect of rapid maxillary expansion with anchorage exclusively onto deciduous teeth performed in the first period of transition. Twenty patients with a lateral cross-bite treated exclusively by a Haas expander in early mixed dentition were retrospectively analyzed before treatment, at appliance removal, and at 21 months out of retention. The sagittal and transverse dimensions, together with the inter-canine arch and irregularity index, were digitally measured on scanned images of dental casts. The patients were compared with three balanced control groups (in total, 60 individuals) matched for gender. Two control groups had the same canine dental class as the treated group at T1, were in the inter-transitional period, and either had or lacked a lateral cross-bite. The last control group was comprised of adolescents in permanent dentition with a dental class I. The statistical analysis was performed by means of repeated-measures ANOVA for paired data and one-way ANOVA, the Kruskal-Wallis test, and the Mann-Whitney test for independent measures (α-level p < 0.05). At the end of follow-up (inter-transitional period of dentition), the dental arch dimensions of treated patients were similar to those of adolescents with a dental class I and significantly wider than those of patients with a lateral cross-bite. Also, the anterior irregularity index was lower among patients who had undergone expansion treatments than in all untreated study participants. The Haas expander anchored to the deciduous teeth is effective in increasing the dental arch width in patients with a lateral cross-bite. The dimensions of the dental arch were modified earlier toward the values of the permanent dentition.

Evaluation of surgically assisted rapid maxillary expansion with piezosurgery versus oscillating saw and chisel osteotomy - a randomized prospective trial.

PubMed

Rana, Majeed; Gellrich, Nils-Claudius; Rana, Madiha; Piffkó, Jozsef; Kater, Wolfgang

2013-02-17

Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10 minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. This method of piezoelectric surgery with all its advantages is going to replace many conventional operating procedures in oral and maxillofacial surgery. CIS 2007-237-M.

Evaluation of surgically assisted rapid maxillary expansion with piezosurgery versus oscillating saw and chisel osteotomy - a randomized prospective trial

PubMed Central

2013-01-01

Background Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Methods Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. Results The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10 minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. Conclusion This method of piezoelectric surgery with all its advantages is going to replace many conventional operating procedures in oral and maxillofacial surgery. Trial registration CIS 2007-237-M PMID:23414112

Fine-scale genetic structure arises during range expansion of an invasive gecko.

PubMed

Short, Kristen Harfmann; Petren, Kenneth

2011-01-01

Processes of range expansion are increasingly important in light of current concerns about invasive species and range shifts due to climate change. Theoretical studies suggest that genetic structuring may occur during range expansion. Ephemeral genetic structure can have important evolutionary implications, such as propagating genetic changes along the wave front of expansion, yet few studies have shown evidence of such structure. We tested the hypothesis that genetic structure arises during range expansion in Hemidactylus mabouia, a nocturnal African gecko recently introduced to Florida, USA. Twelve highly variable microsatellite loci were used to screen 418 individuals collected from 43 locations from four sampling sites across Florida, representing a gradient from earlier (∼1990s) to very recent colonization. We found earlier colonized locations had little detectable genetic structure and higher allelic richness than more recently colonized locations. Genetic structuring was pronounced among locations at spatial scales of tens to hundreds of meters near the leading edge of range expansion. Despite the rapid pace of range expansion in this introduced gecko, dispersal is limited among many suitable habitat patches. Fine-scale genetic structure is likely the result of founder effects during colonization of suitable habitat patches. It may be obscured over time and by scale-dependent modes of dispersal. Further studies are needed to determine if such genetic structure affects adaptation and trait evolution in range expansions and range shifts.

CD137+CD154− Expression As a Regulatory T Cell (Treg)-Specific Activation Signature for Identification and Sorting of Stable Human Tregs from In Vitro Expansion Cultures

PubMed Central

Nowak, Anna; Lock, Dominik; Bacher, Petra; Hohnstein, Thordis; Vogt, Katrin; Gottfreund, Judith; Giehr, Pascal; Polansky, Julia K.; Sawitzki, Birgit; Kaiser, Andrew; Walter, Jörn; Scheffold, Alexander

2018-01-01

Regulatory T cells (Tregs) are an attractive therapeutic tool for several different immune pathologies. Therapeutic Treg application often requires prolonged in vitro culture to generate sufficient Treg numbers or to optimize their functionality, e.g., via genetic engineering of their antigen receptors. However, purity of clinical Treg expansion cultures is highly variable, and currently, it is impossible to identify and separate stable Tregs from contaminating effector T cells, either ex vivo or after prior expansion. This represents a major obstacle for quality assurance of expanded Tregs and raises significant safety concerns. Here, we describe a Treg activation signature that allows identification and sorting of epigenetically imprinted Tregs even after prolonged in vitro culture. We show that short-term reactivation resulted in expression of CD137 but not CD154 on stable FoxP3+ Tregs that displayed a demethylated Treg-specific demethylated region, high suppressive potential, and lack of inflammatory cytokine expression. We also applied this Treg activation signature for rapid testing of chimeric antigen receptor functionality in human Tregs and identified major differences in the signaling requirements regarding CD137 versus CD28 costimulation. Taken together, CD137+CD154− expression emerges as a universal Treg activation signature ex vivo and upon in vitro expansion allowing the identification and isolation of epigenetically stable antigen-activated Tregs and providing a means for their rapid functional testing in vitro. PMID:29467769

CD137+CD154- Expression As a Regulatory T Cell (Treg)-Specific Activation Signature for Identification and Sorting of Stable Human Tregs from In Vitro Expansion Cultures.

PubMed

Nowak, Anna; Lock, Dominik; Bacher, Petra; Hohnstein, Thordis; Vogt, Katrin; Gottfreund, Judith; Giehr, Pascal; Polansky, Julia K; Sawitzki, Birgit; Kaiser, Andrew; Walter, Jörn; Scheffold, Alexander

2018-01-01

Regulatory T cells (Tregs) are an attractive therapeutic tool for several different immune pathologies. Therapeutic Treg application often requires prolonged in vitro culture to generate sufficient Treg numbers or to optimize their functionality, e.g., via genetic engineering of their antigen receptors. However, purity of clinical Treg expansion cultures is highly variable, and currently, it is impossible to identify and separate stable Tregs from contaminating effector T cells, either ex vivo or after prior expansion. This represents a major obstacle for quality assurance of expanded Tregs and raises significant safety concerns. Here, we describe a Treg activation signature that allows identification and sorting of epigenetically imprinted Tregs even after prolonged in vitro culture. We show that short-term reactivation resulted in expression of CD137 but not CD154 on stable FoxP3+ Tregs that displayed a demethylated Treg-specific demethylated region, high suppressive potential, and lack of inflammatory cytokine expression. We also applied this Treg activation signature for rapid testing of chimeric antigen receptor functionality in human Tregs and identified major differences in the signaling requirements regarding CD137 versus CD28 costimulation. Taken together, CD137+CD154- expression emerges as a universal Treg activation signature ex vivo and upon in vitro expansion allowing the identification and isolation of epigenetically stable antigen-activated Tregs and providing a means for their rapid functional testing in vitro .

Competition for Space Is Controlled by Apoptosis-Induced Change of Local Epithelial Topology.

PubMed

Tsuboi, Alice; Ohsawa, Shizue; Umetsu, Daiki; Sando, Yukari; Kuranaga, Erina; Igaki, Tatsushi; Fujimoto, Koichi

2018-06-11

During the initial stage of tumor progression, oncogenic cells spread despite spatial confinement imposed by surrounding normal tissue. This spread of oncogenic cells (winners) is thought to be governed by selective killing of surrounding normal cells (losers) through a phenomenon called "cell competition" (i.e., supercompetition). Although the mechanisms underlying loser elimination are increasingly apparent, it is not clear how winner cells selectively occupy the space made available following loser apoptosis. Here, we combined live imaging analyses of two different oncogenic clones (Yki/YAP activation and Ras activation) in the Drosophila epithelium with computer simulation of tissue mechanics to elucidate such a mechanism. Contrary to the previous expectation that cell volume loss after apoptosis of loser cells was simply compensated for by the faster proliferation of winner cells, we found that the lost volume was compensated for by rapid cell expansion of winners. Mechanistically, the rapid winner-dominated cell expansion was driven by apoptosis-induced epithelial junction remodeling, which causes re-connection of local cellular connectivity (cell topology) in a manner that selectively increases winner apical surface area. In silico experiments further confirmed that repetition of loser elimination accelerates tissue-scale winner expansion through topological changes over time. Our proposed mechanism for linking loser death and winner expansion provides a new perspective on how tissue homeostasis disruption can initiate from an oncogenic mutation. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Implementation of a state-to-state analytical framework for the calculation of expansion tube flow properties

NASA Astrophysics Data System (ADS)

James, C. M.; Gildfind, D. E.; Lewis, S. W.; Morgan, R. G.; Zander, F.

2018-03-01

Expansion tubes are an important type of test facility for the study of planetary entry flow-fields, being the only type of impulse facility capable of simulating the aerothermodynamics of superorbital planetary entry conditions from 10 to 20 km/s. However, the complex flow processes involved in expansion tube operation make it difficult to fully characterise flow conditions, with two-dimensional full facility computational fluid dynamics simulations often requiring tens or hundreds of thousands of computational hours to complete. In an attempt to simplify this problem and provide a rapid flow condition prediction tool, this paper presents a validated and comprehensive analytical framework for the simulation of an expansion tube facility. It identifies central flow processes and models them from state to state through the facility using established compressible and isentropic flow relations, and equilibrium and frozen chemistry. How the model simulates each section of an expansion tube is discussed, as well as how the model can be used to simulate situations where flow conditions diverge from ideal theory. The model is then validated against experimental data from the X2 expansion tube at the University of Queensland.

Effective convergence of the two-particle irreducible 1/N expansion for nonequilibrium quantum fields

NASA Astrophysics Data System (ADS)

Aarts, Gert; Laurie, Nathan; Tranberg, Anders

2008-12-01

The 1/N expansion of the two-particle irreducible effective action offers a powerful approach to study quantum field dynamics far from equilibrium. We investigate the effective convergence of the 1/N expansion in the O(N) model by comparing results obtained numerically in 1+1 dimensions at leading, next-to-leading and next-to-next-to-leading order in 1/N as well as in the weak coupling limit. A comparison in classical statistical field theory, where exact numerical results are available, is made as well. We focus on early-time dynamics and quasiparticle properties far from equilibrium and observe rapid effective convergence already for moderate values of 1/N or the coupling.

Peptide-specific recognition of human cytomegalovirus strains controls adaptive natural killer cells.

PubMed

Hammer, Quirin; Rückert, Timo; Borst, Eva Maria; Dunst, Josefine; Haubner, André; Durek, Pawel; Heinrich, Frederik; Gasparoni, Gilles; Babic, Marina; Tomic, Adriana; Pietra, Gabriella; Nienen, Mikalai; Blau, Igor Wolfgang; Hofmann, Jörg; Na, Il-Kang; Prinz, Immo; Koenecke, Christian; Hemmati, Philipp; Babel, Nina; Arnold, Renate; Walter, Jörn; Thurley, Kevin; Mashreghi, Mir-Farzin; Messerle, Martin; Romagnani, Chiara

2018-05-01

Natural killer (NK) cells are innate lymphocytes that lack antigen-specific rearranged receptors, a hallmark of adaptive lymphocytes. In some people infected with human cytomegalovirus (HCMV), an NK cell subset expressing the activating receptor NKG2C undergoes clonal-like expansion that partially resembles anti-viral adaptive responses. However, the viral ligand that drives the activation and differentiation of adaptive NKG2C + NK cells has remained unclear. Here we found that adaptive NKG2C + NK cells differentially recognized distinct HCMV strains encoding variable UL40 peptides that, in combination with pro-inflammatory signals, controlled the population expansion and differentiation of adaptive NKG2C + NK cells. Thus, we propose that polymorphic HCMV peptides contribute to shaping of the heterogeneity of adaptive NKG2C + NK cell populations among HCMV-seropositive people.

Translations on Telecommunications Policy, Research and Development, Number 28

DTIC Science & Technology

1978-02-09

digital electronics technology — is confident that the 12-watt I’KP (Peak En- velope Tower) single side band radio will perform better and be...PRODUCED WITH FUJITSU TECHNOLOGY, EQUIPMENT Rio de Janeiro 0 GLOBO in Portuguese 21 Dec 77 p 21 [Text] Porto Alegre (0 GLOBO). EDISA [ Digital ...10042 CSO: 5500 25 PERU TELEPHONE SERVICE TO UNDERGO COSTLY EXPANSION Plan To Add Lines Approved Lima EL COMERCIO in Spanish 1? Nov 77 Front

Patient Discomfort During and After Surgically Assisted Rapid Maxillary Expansion Under Local Anaesthesia.

PubMed

Laino, Luigi; Troiano, Giuseppe; Dioguardi, Mario; Perillo, Letizia; Laino, Gregorio; Lo Muzio, Lorenzo; Cicciù, Marco

2016-05-01

The aim of this study was to evaluate whether surgically assisted rapid maxillary expansion (SARME) could be performed under local anaesthesia and to understand the patient discomfort associated with this protocol. Patient discomfort was compared during and after 2 different types of oral surgical treatments in the same patients. Odontectomies for impacted lower third molar (control) were compared with SARME procedures (test) that were also performed under local anaesthesia. A visual analogic scale was used for each patient to quantify his or her discomfort before and after surgery. A total of 47 patients required 1 of these surgeries and were enrolled in this study. No statistically differences (P >0.05) were observed between the control and test groups. The results of this study suggest that SARME can be safely performed under local anesthesia because the intra- and postoperative discomfort levels were similar to those of other procedures that are typically performed under local anesthesia.

Does rapid maxillary expansion increase nasopharyngeal space and improve nasal airway resistance?

PubMed

Langer, Marjorie Regina Eguren; Itikawa, Carla Enoki; Valera, Fabiana Cardoso Pereira; Matsumoto, Mírian Aiko Nakane; Anselmo-Lima, Wilma Terezinha

2011-01-01

To evaluate the effect of rapid maxillary expansion (RME) on the dimension of the nasopharyngeal space and its relation to nasal airway resistance. Twenty-five school-age children (from 7 to 10 year-old) with mouth and/or mixed breathing, with mixed dentition and uni- or bilateral posterior crossbite involving the deciduous canines and the first permanent molars, were evaluated. RME was placed and remained during 90 days. Rhinomanometry and orthodontic documentation were performed at four different times, i.e., before (T(1)), immediately after (T(2)), 90 days (T(3)) and 30 months (T(4)) after RME. Differences in nasopharyngeal area and in nasal airway resistance were observed only 30 months after RME, and could be explained by facial growth, and not because of the orthodontic procedure. RME does not influence on nasopharyngeal area or nasal airway resistance in long-term evaluation. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

A rapid method for optimization of the rocket propulsion system for single-stage-to-orbit vehicles

NASA Technical Reports Server (NTRS)

Eldred, C. H.; Gordon, S. V.

1976-01-01

A rapid analytical method for the optimization of rocket propulsion systems is presented for a vertical take-off, horizontal landing, single-stage-to-orbit launch vehicle. This method utilizes trade-offs between propulsion characteristics affecting flight performance and engine system mass. The performance results from a point-mass trajectory optimization program are combined with a linearized sizing program to establish vehicle sizing trends caused by propulsion system variations. The linearized sizing technique was developed for the class of vehicle systems studied herein. The specific examples treated are the optimization of nozzle expansion ratio and lift-off thrust-to-weight ratio to achieve either minimum gross mass or minimum dry mass. Assumed propulsion system characteristics are high chamber pressure, liquid oxygen and liquid hydrogen propellants, conventional bell nozzles, and the same fixed nozzle expansion ratio for all engines on a vehicle.

[Cone-beam CT evaluation of nasomaxillary complex and upper airway following rapid maxillary expansion].

PubMed

Li, Lei; Qi, Suqing; Wang, Hongwei; Ren, Sufeng; Ban, Jiandong

2015-07-01

To evaluate the naso-maxillary complex width and pharyngeal airway volume changes after rapid maxillary expansion (RME). Thirty-five patients were selected (18 males, 17 females, mean age, 12.1 ± 1.1 years). All patients underwent orthodontic treatment with Hyrax palatal expanders. Cone-beam CT (CBCT) scan was taken before treatment (T0), 16 days (T1) and three months (T3) after RME. Naso-maxillary complex width and pharyngeal airway volume were measured. After treatment the width of piriform aperture and maxillary width were significantly increased compared with that before treatment (P < 0.05). Three months after RME, no statistical difference was found in maxillary width compared with that before treatment. The nasopharyngeal volume significantly increased by 29.9% compared with that before treatment (P < 0.05), and the volume remained relatively stable after three months. RME resulted in a significant increase in the naso-maxillary complex width and nasopharyngeal volume.

Collapse of axion stars

DOE PAGES

Eby, Joshua; Leembruggen, Madelyn; Suranyi, Peter; ...

2016-12-15

Axion stars, gravitationally bound states of low-energy axion particles, have a maximum mass allowed by gravitational stability. Weakly bound states obtaining this maximum mass have sufficiently large radii such that they are dilute, and as a result, they are well described by a leading-order expansion of the axion potential. Here, heavier states are susceptible to gravitational collapse. Inclusion of higher-order interactions, present in the full potential, can give qualitatively different results in the analysis of collapsing heavy states, as compared to the leading-order expansion. In this work, we find that collapsing axion stars are stabilized by repulsive interactions present inmore » the full potential, providing evidence that such objects do not form black holes. In the last moments of collapse, the binding energy of the axion star grows rapidly, and we provide evidence that a large amount of its energy is lost through rapid emission of relativistic axions.« less

Rapid analysis of scattering from periodic dielectric structures using accelerated Cartesian expansions.

PubMed

Baczewski, Andrew D; Miller, Nicholas C; Shanker, Balasubramaniam

2012-04-01

The analysis of fields in periodic dielectric structures arise in numerous applications of recent interest, ranging from photonic bandgap structures and plasmonically active nanostructures to metamaterials. To achieve an accurate representation of the fields in these structures using numerical methods, dense spatial discretization is required. This, in turn, affects the cost of analysis, particularly for integral-equation-based methods, for which traditional iterative methods require O(N2) operations, N being the number of spatial degrees of freedom. In this paper, we introduce a method for the rapid solution of volumetric electric field integral equations used in the analysis of doubly periodic dielectric structures. The crux of our method is the accelerated Cartesian expansion algorithm, which is used to evaluate the requisite potentials in O(N) cost. Results are provided that corroborate our claims of acceleration without compromising accuracy, as well as the application of our method to a number of compelling photonics applications.

Neptune

NASA Image and Video Library

1999-10-14

This photograph of Neptune shows three of the features that NASA Voyager 2 has been photographing during recent weeks. At the north is the Great Dark Spot, accompanied by bright, white clouds that undergo rapid changes in appearance.

The Formation and Early Evolution of a Coronal Mass Ejection and its Associated Shock Wave on 2014 January 8

NASA Astrophysics Data System (ADS)

Wan, Linfeng; Cheng, Xin; Shi, Tong; Su, Wei; Ding, M. D.

2016-08-01

In this paper, we study the formation and early evolution of a limb coronal mass ejection (CME) and its associated shock wave that occurred on 2014 January 8. The extreme ultraviolet (EUV) images provided by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory disclose that the CME first appears as a bubble-like structure. Subsequently, its expansion forms the CME and causes a quasi-circular EUV wave. Interestingly, both the CME and the wave front are clearly visible at all of the AIA EUV passbands. Through a detailed kinematical analysis, it is found that the expansion of the CME undergoes two phases: a first phase with a strong but transient lateral over-expansion followed by a second phase with a self-similar expansion. The temporal evolution of the expansion velocity coincides very well with the variation of the 25-50 keV hard X-ray flux of the associated flare, which indicates that magnetic reconnection most likely plays an important role in driving the expansion. Moreover, we find that, when the velocity of the CME reaches ˜600 km s-1, the EUV wave starts to evolve into a shock wave, which is evidenced by the appearance of a type II radio burst. The shock’s formation height is estimated to be ˜0.2 R sun, which is much lower than the height derived previously. Finally, we also study the thermal properties of the CME and the EUV wave. We find that the plasma in the CME leading front and the wave front has a temperature of ˜2 MK, while that in the CME core region and the flare region has a much higher temperature of ≥8 MK.

Adipose-Derived Stromal Vascular Fraction Differentially Expands Breast Progenitors in Tissue Adjacent to Tumors Compared to Healthy Breast Tissue

PubMed Central

Chatterjee, Sumanta; Laliberte, Mike; Blelloch, Sarah; Ratanshi, Imran; Safneck, Janice; Buchel, Ed

2015-01-01

Background: Autologous fat grafts supplemented with adipose-derived stromal vascular fraction are used in reconstructive and cosmetic breast procedures. Stromal vascular fraction contains adipose-derived stem cells that are thought to encourage wound healing, tissue regeneration, and graft retention. Although use of stromal vascular fraction has provided exciting perspectives for aesthetic procedures, no studies have yet been conducted to determine whether its cells contribute to breast tissue regeneration. The authors examined the effect of these cells on the expansion of human breast epithelial progenitors. Methods: From patients undergoing reconstructive breast surgery following mastectomies, abdominal fat, matching tissue adjacent to breast tumors, and the contralateral non–tumor-containing breast tissue were obtained. Ex vivo co-cultures using breast epithelial cells and the stromal vascular fraction cells were used to study the expansion potential of breast progenitors. Breast reduction samples were collected as a source of healthy breast cells. Results: The authors observed that progenitors present in healthy breast tissue or contralateral non–tumor-containing breast tissue showed significant and robust expansion in the presence of stromal vascular fraction (5.2- and 4.8-fold, respectively). Whereas the healthy progenitors expanded up to 3-fold without the stromal vascular fraction cells, the expansion of tissue adjacent to breast tumor progenitors required the presence of stromal vascular fraction cells, leading to a 7-fold expansion, which was significantly higher than the expansion of healthy progenitors with stromal vascular fraction. Conclusions: The use of stromal vascular fraction might be more beneficial to reconstructive operations following mastectomies compared with cosmetic corrections of the healthy breast. Future studies are required to examine the potential risk factors associated with its use. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V. PMID:26090768

Cycle expansions: From maps to turbulence

NASA Astrophysics Data System (ADS)

Lan, Y.

2010-03-01

We present a derivation, a physical explanation and applications of cycle expansions in different dynamical systems, ranging from simple one-dimensional maps to turbulence in fluids. Cycle expansion is a newly devised powerful tool for computing averages of physical observables in nonlinear chaotic systems which combines many innovative ideas developed in dynamical systems, such as hyperbolicity, invariant manifolds, symbolic dynamics, measure theory and thermodynamic formalism. The concept of cycle expansion has a deep root in theoretical physics, bearing a close analogy to cumulant expansion in statistical physics and effective action functional in quantum field theory, the essence of which is to represent a physical system in a hierarchical way by utilizing certain multiplicative structures such that the dominant parts of physical observables are captured by compact, maneuverable objects while minor detailed variations are described by objects with a larger space and time scale. The technique has been successfully applied to many low-dimensional dynamical systems and much effort has recently been made to extend its use to spatially extended systems. For one-dimensional systems such as the Kuramoto-Sivashinsky equation, the method turns out to be very effective while for more complex real-world systems including the Navier-Stokes equation, the method is only starting to yield its first fruits and much more work is needed to enable practical computations. However, the experience and knowledge accumulated so far is already very useful to a large set of research problems. Several such applications are briefly described in what follows. As more research effort is devoted to the study of complex dynamics of nonlinear systems, cycle expansion will undergo a fast development and find wide applications.

Effects of processing moisture on the physical properties and in vitro digestibility of starch and protein in extruded brown rice and pinto bean composite flours.

PubMed

Sumargo, Franklin; Gulati, Paridhi; Weier, Steven A; Clarke, Jennifer; Rose, Devin J

2016-11-15

The influence of pinto bean flour and processing moisture on the physical properties and in vitro digestibility of rice-bean extrudates has been investigated. Brown rice: pinto bean flour (0%, 15%, 30%, and 45% bean flour) were extruded under 5 moisture conditions (17.2%, 18.1%, 18.3%, 19.5%, and 20.1%). Physical properties [bulk density, unit density, radial expansion, axial expansion, overall expansion, specific volume, hardness, color, water solubility index, and water absorption index] and in vitro starch and protein digestibilities were determined. Increasing bean flour and processing moisture increased density and hardness while decreasing expansion. Rapidly digestible starch decreased and resistant starch increased as bean substitution and processing moisture increased. In vitro protein digestibility increased with increasing bean flour or with decreasing processing moisture. Incorporating bean flour into extruded snacks can negatively affect physical attributes (hardness, density, and expansion) while positively affecting in vitro starch (decrease) and protein (increase) digestibilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterisation of aerosol combustible mixtures generated using condensation process

NASA Astrophysics Data System (ADS)

Saat, Aminuddin; Dutta, Nilabza; Wahid, Mazlan A.

2012-06-01

An accidental release of a liquid flammable substance might be formed as an aerosol (droplet and vapour mixture). This phenomenon might be due to high pressure sprays, pressurised liquid leaks and through condensation when hot vapour is rapidly cooled. Such phenomena require a fundamental investigation of mixture characterisation prior to any subsequent process such as evaporation and combustion. This paper describes characterisation study of droplet and vapour mixtures generated in a fan stirred vessel using condensation technique. Aerosol of isooctane mixtures were generated by expansion from initially a premixed gaseous fuel-air mixture. The distribution of droplets within the mixture was characterised using laser diagnostics. Nearly monosized droplet clouds were generated and the droplet diameter was defined as a function of expansion time. The effect of changes in pressure, temperature, fuel-air fraction and expansion ratio on droplet diameter was evaluated. It is shown that aerosol generation by expansion was influenced by the initial pressure and temperature, equivalence ratio and expansion rates. All these parameters affected the onset of condensation which in turn affected the variation in droplet diameter.

Model for the dynamics of two interacting axisymmetric spherical bubbles undergoing small shape oscillations

PubMed Central

Kurihara, Eru; Hay, Todd A.; Ilinskii, Yurii A.; Zabolotskaya, Evgenia A.; Hamilton, Mark F.

2011-01-01

Interaction between acoustically driven or laser-generated bubbles causes the bubble surfaces to deform. Dynamical equations describing the motion of two translating, nominally spherical bubbles undergoing small shape oscillations in a viscous liquid are derived using Lagrangian mechanics. Deformation of the bubble surfaces is taken into account by including quadrupole and octupole perturbations in the spherical-harmonic expansion of the boundary conditions on the bubbles. Quadratic terms in the quadrupole and octupole amplitudes are retained, and surface tension and shear viscosity are included in a consistent manner. A set of eight coupled second-order ordinary differential equations is obtained. Simulation results, obtained by numerical integration of the model equations, exhibit qualitative agreement with experimental observations by predicting the formation of liquid jets. Simulations also suggest that bubble-bubble interactions act to enhance surface mode instability. PMID:22088009

Homogenous Population Genetic Structure of the Non-Native Raccoon Dog (Nyctereutes procyonoides) in Europe as a Result of Rapid Population Expansion

PubMed Central

Drygala, Frank; Korablev, Nikolay; Ansorge, Hermann; Fickel, Joerns; Isomursu, Marja; Elmeros, Morten; Kowalczyk, Rafał; Baltrunaite, Laima; Balciauskas, Linas; Saarma, Urmas; Schulze, Christoph; Borkenhagen, Peter; Frantz, Alain C.

2016-01-01

The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides) in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species’ dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large ‘central’ population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations. PMID:27064784

Is There Any Evidence for Rapid, Genetically-Based, Climatic Niche Expansion in the Invasive Common Ragweed?

PubMed

Gallien, Laure; Thuiller, Wilfried; Fort, Noémie; Boleda, Marti; Alberto, Florian J; Rioux, Delphine; Lainé, Juliette; Lavergne, Sébastien

2016-01-01

Climatic niche shifts have been documented in a number of invasive species by comparing the native and adventive climatic ranges in which they occur. However, these shifts likely represent changes in the realized climatic niches of invasive species, and may not necessarily be driven by genetic changes in climatic affinities. Until now the role of rapid niche evolution in the spread of invasive species remains a challenging issue with conflicting results. Here, we document a likely genetically-based climatic niche expansion of an annual plant invader, the common ragweed (Ambrosia artemisiifolia L.), a highly allergenic invasive species causing substantial public health issues. To do so, we looked for recent evolutionary change at the upward migration front of its adventive range in the French Alps. Based on species climatic niche models estimated at both global and regional scales we stratified our sampling design to adequately capture the species niche, and localized populations suspected of niche expansion. Using a combination of species niche modeling, landscape genetics models and common garden measurements, we then related the species genetic structure and its phenotypic architecture across the climatic niche. Our results strongly suggest that the common ragweed is rapidly adapting to local climatic conditions at its invasion front and that it currently expands its niche toward colder and formerly unsuitable climates in the French Alps (i.e. in sites where niche models would not predict its occurrence). Such results, showing that species climatic niches can evolve on very short time scales, have important implications for predictive models of biological invasions that do not account for evolutionary processes.

Environmentally benign formation of polymeric microspheres by rapid expansion of supercritical carbon dioxide solution with a nonsolvent.

PubMed

Matsuyama, K; Mishima, K; Umemoto, H; Yamaguchi, S

2001-10-15

A novel method is reported for forming polymer microparticles, which reduce atmospheric emissions of environmentally harmful volatile organic compounds such as toluene and xylene used as paint solvent in paint industry. The polymer microparticles have formed through rapid expansion from supercritical solution with a nonsolvent (RESS-N). Solubilization of poly(styrene)-b-(poly(methyl methacrylate)-co-poly (glycidyl methacrylate)) copolymer(PS-b-(PMMA-co-PGMA), MW = 5000, PS/PMMA/PGMA = 2/5/3), poly(ethylene glycol) (PEG, M. W = 4000), bisphenol A type epoxy resin (EP, MW = 3000), poly(methyl methacrylate) (PMMA; MW = 15000, 75000, 120000), and poly(oxyalkylene) alkylphenyl ether (MW = 4000) in carbon dioxide (CO2) was achieved with the use of small alcohols as cosolvents. The solubility of the PS-b-(PMMA-co-PGMA) is extremely low in either CO2 or ethanol but becomes 20 wt % in a mixture of the two. Because ethanol is a nonsolvent for the polymer, it can be used as a cosolvent in rapid expansion from supercritical solution to produce 1-3 microm particles that do not agglomerate. Obtained polymer particles by RESS-N were applied as powder coatings. The resulting coatings have a smooth and coherent film. The particle size distribution of microspheres was controlled by changing the polymer concentration, preexpansion pressure, temperature, and injection distance. The feed compositions were more effective than the other factors in controlling the particle size. The polymeric microparticles formed by RESS-N method can be utilized to make the thin coating film without anytoxic organic solvents and/or surfactants.

Condylar positional changes in rapid maxillary expansion assessed with cone-beam computer tomography.

PubMed

McLeod, Lauren; Hernández, Ivonne A; Heo, Giseon; Lagravère, Manuel O

2016-09-01

The aim of this study was to determine the presence of condylar spatial changes in patients having rapid maxillary expansion treatments compared to a control group. Thirty-seven patients with maxillary transverse deficiency (11-17 years old) were randomly allocated into two groups (one treatment group - tooth borne expander [hyrax] - and one control group). Cone-beam computer tomographies (CBCT) were obtained from each patient at two time points (initial T1 and at removal of appliance at 6 months T2). CBCTs were analyzed using AVIZO software and landmarks were placed on the upper first molars and premolars, cranial base, condyles and glenoid fossa. Descriptive statistics, intraclass correlation coefficients and one-way Anova analysis were used to determine if there was a change in condyle position with respect to the glenoid fossa and cranial base and if there was a statistically significant difference between groups. Descriptive statistics show that changes in the condyle position with respect to the glenoid fossa were minor in both groups (<1.9mm average for both groups). The largest difference in both groups was found when measuring the distance between the left and right condyle heads. When comparing changes between both groups, no statistically significant difference was found between changes in the condyles (P<0.05). Rapid maxillary expansion treatments present mild effects/changes on the condylar position. Nevertheless, these changes do not present a significant difference with controls, thus not constituting a limitation for applying this treatment. Copyright © 2016 CEO. Published by Elsevier Masson SAS. All rights reserved.

Gold-catalyzed and N-iodosuccinimide-mediated cyclization of gamma-substituted allenamides.

PubMed

Hyland, Christopher J T; Hegedus, Louis S

2006-10-27

Chiral gamma-substituted allenamides have been shown to undergo efficient gold-catalyzed and N-iodosuccinimide-mediated cyclization to highly functionalized dihydrofurans. These reactions proceed rapidly and without loss of stereochemistry.

Evaluation of WES One-Dimensional Dynamic Soil Testing Procedures.

DTIC Science & Technology

1983-06-01

relations: 18 AC - (2K +4G (6)a so I so r (6) Dividing the stress reduction Aa by a from equation (5), we obtain ana r estimate of the fractional error in...walls, the radial expansion of the soil caused by the expansion of the steel side walls, and the nonuniform stress and strain states in the sample...is applied rapidly, the stress state in the soil at the steel base may be very different from that at the top surface of the soil. With such

Geothermal Technologies Program - Geothermal Energy: Putting Creative Ideas to Work (Green Jobs)

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

None

2010-06-01

Rapid expansion of U.S. geothermal capacity is opening new job opportunities across the nation. With more than 3,000 megawatts (MW) already installed, the United States leads the world in existing geothermal capacity.

The Water Sciences: Present and Future.

ERIC Educational Resources Information Center

Sasseville, J. L.; de Marsily, G.

1998-01-01

Explores factors that can explain the rapid evolution of the water sciences. Discusses the investment in measuring systems that allow characterizations of water properties and the expansion of mathematical and systemic approaches to the interpretation of data. Contains 23 references. (DDR)

Impact of Kansas Ethanol Production on Kansas Transportation

DOT National Transportation Integrated Search

2009-10-01

The rapid expansion of the biofuel industry has driven the Kansas agricultural transportation market into a new era. Nationally, fuel alcohol production increased 452 percent in the 2000-2008 period. The number of ethanol production plants rose 215 p...

An evaluation of bridge deck joint sealing systems in Virginia.

DOT National Transportation Integrated Search

2003-01-01

The design and fabrication of bridge expansion joint (or movement) systems comprise a rapidly evolving industry. New designs are constantly being presented for trial, often on a piecemeal basis. Occasionally, failures of products occur without suffic...

Galactic Spiral Shocks with Thermal Instability in Vertically Stratified Galactic Disks

NASA Astrophysics Data System (ADS)

Kim, Chang-Goo; Kim, Woong-Tae; Ostriker, Eve C.

2010-09-01

Galactic spiral shocks are dominant morphological features and believed to be responsible for substructure formation within spiral arms in disk galaxies. They can also contribute a substantial amount of kinetic energy to the interstellar gas by tapping the (differential) rotational motion. We use numerical hydrodynamic simulations to investigate dynamics and structure of spiral shocks with thermal instability (TI) in vertically stratified galactic disks, focusing on environmental conditions (of heating and the galactic potential) similar to the Solar neighborhood. We initially consider an isothermal disk in vertical hydrostatic equilibrium and let it evolve subject to interstellar cooling and heating as well as a stellar spiral potential. Due to TI, a disk with surface density Σ0 >= 6.7 M sun pc-2 rapidly turns to a thin dense slab near the midplane sandwiched between layers of rarefied gas. The imposed spiral potential leads to a vertically curved shock that exhibits strong flapping motions in the plane perpendicular to the arm. The overall flow structure at saturation is comprised of the arm, postshock expansion zone, and interarm regions that occupy typically 10%, 20%, and 70% of the arm-to-arm distance, in which the gas resides for 15%, 30%, and 55% of the arm-to-arm crossing time, respectively. The flows are characterized by transitions from rarefied to dense phases at the shock and from dense to rarefied phases in the postshock expansion zone, although gas with too-large postshock-density does not undergo this return phase transition, instead forming dense condensations. If self-gravity is omitted, the shock flapping drives random motions in the gas, but only up to ~2-3 km s-1 in the in-plane direction and less than 2 km s-1 in the vertical direction. Time-averaged shock profiles show that the spiral arms in stratified disks are broader and less dense compared to those in unstratified models, and that the vertical density distribution is overall consistent with local effective hydrostatic equilibrium. Inclusion of self-gravity increases the dense gas fraction by a factor of ~2 and raises the in-plane velocity dispersion to ~5-7 km s-1. When the disks are massive enough, with Σ0 >= 5 M sun pc-2, self-gravity promotes formation of bound clouds that repeatedly collide with each other in the arm and break up in the postshock expansion zone.

A "coca-cola" shape: cultural change, body image, and eating disorders in San Andrés, Belize.

PubMed

Anderson-Fye, Eileen P

2004-12-01

Eating disorders have been associated with developing nations undergoing rapid social transition, including participation in a global market economy and heavy media exposure. San Andrés, Belize, a community with many risk factors associated with the cross-cultural development of eating disorders, has shown remarkable resistance to previously documented patterns, despite a local focus on female beauty. Drawing on longitudinal person-centered ethnography with adolescent girls, this article examines why this community appears exceptional in light of the literature. First, community beauty and body image ideals and practices are explicated. Then, a protective ethnopsychology is proposed as a key mediating factor of the rapid socio-cultural change among young women. Finally, possible nascent cases of eating disordered behavior are discussed in light of their unique phenomenology: that is, having to do more with economic opportunity in the tourism industry and less with personal distress or desire for thinness. Close, meaning-centered examination of eating and body image practices may aid understanding and prevention of eating disorders among adolescents undergoing rapid social change in situations of globalization and immigration.

Secondary pneumatization of the maxillary sinus in callitrichid primates: insights from immunohistochemistry and bone cell distribution.

PubMed

Smith, Timothy D; Rossie, James B; Cooper, Gregory M; Mooney, Mark P; Siegel, Michael I

2005-08-01

The paranasal sinuses remain elusive both in terms of function and in the proximate mechanism of their development. The present study sought to describe the maxillary sinuses (MSs) in three species of callitrichid primates at birth, a time when secondary pneumatization occurs rapidly in humans. The MSs were examined in serially sectioned and stained slides from the heads of two Callithrix jacchus, one Leontopithecus rosalia, and two Saguinus geoffroyi. Specimens were examined microscopically regarding the distribution of osteoclasts and osteoblasts along the osseous boundaries of the MS and other parts of the maxillary bone. Selected sections were immunohistochemically evaluated for the distribution of osteopontin (OPN), which facilitates osteoclast binding. Taken together, OPN immunoreactivity and bone cell distribution suggested trends of bone resorption/deposition that were consistent among species for the superior (roof) and inferior (floor) boundaries of the MS. Expansion at the roof and floor of the MS appeared to correspond to overall vertical midfacial growth in callitrichids. Much more variability was noted for the lateral (alveolar) and medial (nasal walls) of the MS. Unlike the other species, the nasal wall of Saguinus was static and mostly composed of inferior portions of the nasal capsule that were undergoing endochondral ossification. The variation seen in the alveolar walls may relate to the presence or absence of adjacent structures, although it was noted that adjacency of deciduous molars influenced medial drift of the alveolar wall in Saguinus but not Leontopithecus. The results of this study are largely consistent with the "structural" or "architectural" hypothesis of sinus formation with respect to vertical MS enlargement, and the variable cellular/OPN distribution found along the nasal and alveolar walls was evocative of Witmer's (J Vert Paleontol 1997;17:1-73) epithelial hypothesis in revealing that most expansion occurred in regions unopposed by adjacent structures. (c) 2005 Wiley-Liss, Inc.

Unimolecular thermal decomposition of phenol and d5-phenol: Direct observation of cyclopentadiene formation via cyclohexadienone

NASA Astrophysics Data System (ADS)

Scheer, Adam M.; Mukarakate, Calvin; Robichaud, David J.; Nimlos, Mark R.; Carstensen, Hans-Heinrich; Barney Ellison, G.

2012-01-01

The pyrolyses of phenol and d5-phenol (C6H5OH and C6D5OH) have been studied using a high temperature, microtubular (μtubular) SiC reactor. Product detection is via both photon ionization (10.487 eV) time-of-flight mass spectrometry and matrix isolation infrared spectroscopy. Gas exiting the heated reactor (375 K-1575 K) is subject to a free expansion after a residence time in the μtubular reactor of approximately 50-100 μs. The expansion from the reactor into vacuum rapidly cools the gas mixture and allows the detection of radicals and other highly reactive intermediates. We find that the initial decomposition steps at the onset of phenol pyrolysis are enol/keto tautomerization to form cyclohexadienone followed by decarbonylation to produce cyclopentadiene; C6H5OH → c-C6H6 = O → c-C5H6 + CO. The cyclopentadiene loses a H atom to generate the cyclopentadienyl radical which further decomposes to acetylene and propargyl radical; c-C5H6 → c-C5H5 + H → HC≡CH + HCCCH2. At higher temperatures, hydrogen loss from the PhO-H group to form phenoxy radical followed by CO ejection to generate the cyclopentadienyl radical likely contributes to the product distribution; C6H5O-H → C6H5O + H → c-C5H5 + CO. The direct decarbonylation reaction remains an important channel in the thermal decomposition mechanisms of the dihydroxybenzenes. Both catechol (o-HO-C6H4-OH) and hydroquinone (p-HO-C6H4-OH) are shown to undergo decarbonylation at the onset of pyrolysis to form hydroxycyclopentadiene. In the case of catechol, we observe that water loss is also an important decomposition channel at the onset of pyrolysis.

Coupled social and ecological outcomes of agricultural intensification in Costa Rica and the future of biodiversity conservation in tropical agricultural regions

NASA Astrophysics Data System (ADS)

Sanfiorenzo, A. R.; Waits, L.; Finegan, B.; Shaver, I.; Chain Guadarrama, A.; Cleary, K.; Santiago-Garcia, R.; Hormel, L.; Vierling, L. A.; Bosque-Perez, N.; DeClerck, F.; Fagan, M. E.; Sibelet, N.

2016-12-01

Tropical ecosystem conversion to agriculture has caused widespread habitat loss and created fragmented landscapes composed of remnant forest patches embedded in a matrix of agricultural land uses. Non-traditional agricultural export (NTAE) crops such as pineapple are rapidly replacing multiuse landscapes characterized by a diverse matrix of pasture and smallholder crops with intensive, large-scale, monoculture plantations. Using an interdisciplinary approach, we examine the coupled social and ecological implications of agricultural intensification Guided by frameworks from political economy, landscape ecology and landscape genetics we: (1) describe the social and economic implications of pineapple expansion, specifically the concentration of land, labor and financial resources, (2) quantify pineapple cultivation's spatial characteristics, and (3) assess the effects of pineapple expansion on surrounding forest ecosystems, on the agricultural matrix and on biodiversity conservation. Our results indicate that pineapple production concentrates land, labor, and financial resources, which has a homogenizing effect on the agricultural economy in the study region. This constrains farm-based livelihoods, with larger implications for food security and agricultural diversity. Landscape ecology and genetics analyses further reveal how pineapple production simplifies and homogenizes the agricultural matrix between forest patches, which increase the genetic structure and reduce the genetic diversity of Symphonia globulifera a forest understory tree species. To offset the effects of agricultural intensification on social and environmental systems, we recommend developing landscape level land use planning capacity. Furthermore, agricultural and conservation policy reform is needed to promote landscape heterogeneity and economic diversity within the agricultural sector. Our interdisciplinary research provides a detailed examination of the social and ecological impacts of agricultural intensification in a tropical landscape, and offers recommendations for improvement relevant not only to our study region but to the many other tropical landscapes currently undergoing non-traditional agricultural export driven agricultural intensification.

Prehospital care training in a rapidly developing economy: a multi-institutional study.

PubMed

Vyas, Dinesh; Hollis, Michael; Abraham, Rohit; Rustagi, Neeti; Chandra, Siddharth; Malhotra, Ajai; Rajpurohit, Vikas; Purohit, Harshada; Pal, Ranabir

2016-06-01

The trauma pandemic is one of the leading causes of death worldwide but especially in rapidly developing economies. Perhaps, a common cause of trauma-related mortality in these settings comes from the rapid expansion of motor vehicle ownership without the corresponding expansion of national prehospital training in developed countries. The resulting road traffic injuries often never make it to the hospital in time for effective treatment, resulting in preventable disability and death. The current article examines the development of a medical first responder training program that has the potential to reduce this unnecessary morbidity and mortality. An intensive training workshop has been differentiated into two progressive tiers: acute trauma training (ATT) and broad trauma training (BTT) protocols. These four-hour and two-day protocols, respectively, allow for the mass education of laypersons-such as police officials, fire brigade, and taxi and/or ambulance drivers-who are most likely to interact first with prehospital victims. Over 750 ATT participants and 168 BTT participants were trained across three Indian educational institutions at Jodhpur and Jaipur. Trainees were given didactic and hands-on education in a series of critical trauma topics, in addition to pretraining and post-training self-assessments to rate clinical confidence across curricular topics. Two-sample t-test statistical analyses were performed to compare pretraining and post-training confidence levels. Program development resulted in recruitment of a variety of career backgrounds for enrollment in both our ATT and BTT workshops. The workshops were run by local physicians from a wide spectrum of medical specialties and previously ATT-trained police officials. Statistically significant improvements in clinical confidence across all curricular topics for ATT and BTT protocols were identified (P < 0.0001). In addition, improvement in confidence after BTT training was similar in Jodhpur compared with Jaipur. These results suggest a promising level of reliability and reproducibility across different geographic areas in rapidly developing settings. Program expansion can offer an exponential growth in the training rate of medical first responders, which can help curb the trauma-related mortality in rapidly developing economies. Future directions will include clinical competency assessments and further progressive differentiation into higher tiers of trauma expertise. Published by Elsevier Inc.

Patterns and drivers of Early Holocene vegetation dynamics in Central Europe

NASA Astrophysics Data System (ADS)

Theuerkauf, Martin

2015-04-01

The rapid warming of the Holocene induced the rearrangement of vegetation across Europe, including the widely synchronous and rapid expansion of hazel (Corylus avellana) at around 10.6 ka BP (Giesecke et al., 2011). The simultaneity of the hazel expansion across large parts of Europe suggests that a climate shift has triggered that expansion. However, it remains poorly understood, which climate parameter has been effective (Huntley, 1993) because hazel expanded simultaneously in areas that today clearly differ in climate. To better understand the causes we studied Early Holocene vegetation dynamics in NE Germany in high temporal and spatial resolution. Analysis combines pollen data from 60 sites, including high resolution data sets, with present-day site patterns of soil and relief using the extended downscaling approach. Using forward modeling of pollen deposition in each sample site the method seeks that vegetation composition on each site type that produces modeled pollen deposition most similar to empiric pollen deposition. The results (Theuerkauf et al., 2014) indicate that first populations of hazel established soon after the Holocene warming at 11.2 ka. These populations were still small and possibly restricted to warm loving slopes, indicating that low summer warmth was the limiting factor. The widespread expansion of hazel started only after 10.8 ka, possibly following a shift to greater summer warmth. Hazel primarily expanded on sites that are today covered by gleyic soils, from which it largely expelled tree birch. Hazel thus obviously could only expand on sites that received additional wetness from ground- and stagnant water. Giesecke T., Bennett K.D., Birks H.J.B., Bjune A.E., Bozilova E., Feurdean A., Finsinger W., Froyd C., Pokorný P., Rösch M., Seppä H., Tonkov S., Valsecchi V., & Wolters S. (2011) The pace of Holocene vegetation change - testing for synchronous developments. Quaternary Science Reviews, 30, 2805-2814. Huntley B. (1993) Rapid early-Holocene migration and high abundance of hazel (Corylus avellana L.): alternative hypotheses. Climate change and human impact on the landscape (ed. by F.M. Chambers), pp. 205-215. Chapman and Hall, London. Theuerkauf M., Bos J.A.A., Jahns S., Janke W., Kuparinen A., Stebich M., & Joosten H. (2014) Corylus expansion and persistent openness in the early Holocene vegetation of northern central Europe. Quaternary Science Reviews, 90, 183-198.

Formation of polymeric and organic nanoparticles by RESS and RESOLV

NASA Astrophysics Data System (ADS)

Sane, Amporn

The goal of this work was to obtain an improved fundamental understanding of the formation of organic and polymeric particles by the rapid expansion of supercritical solutions into either air (RESS) or liquid solvents (RESOLV). Rapid expansion of a fluorinated tetraphenylporphyrin, 5,10,15,20-tetrakis(3,5-bis(trifluoromethyl)phenyl)porphyrin (TBTPP), from supercritical solutions of carbon dioxide was investigated. Surprisingly, true nanoparticles (38 +/- 9 nm) were produced by RESS, independent of porphyrin concentration, degree of saturation, and pre-expansion pressure. Particle size increased in a well-behaved manner with pre-expansion temperature (Tpre). RESOLV of TBTPP-CO2 solutions was investigated both for minimizing particle growth in the free jet and for preventing particle agglomeration. Rapid expansion into an aqueous solution of 0.025 wt % Pluronic F68 produced stable nanoparticle (28 +/- 9 nm) suspensions, independent of the processing conditions selected. The fact that nanoparticles were produced by RESS of TBTPP, vs. the microparticles reported with other organics, can be explained in terms of Friedlander's collision-coalescence theory and the solid-state diffusion coefficient D, which is low for this system because of the high melting point (Tm = 388°C) of TBTPP. The effect of D (which is ∝ exp(-Tm/Tpre)) on RESS was further investigated by using a polymer as the solute, as T m can be varied via the molecular weight without changes in chemical properties. RESS experiments on poly(L-lactide) (PLLA) with two different melting points (Tm = 121°C and Mw = 1340; T m = 162°C and Mw = 6050) in CO2-THF mixtures were performed. Typical PLLA products consisted of both nanoparticles (30--100 nm) and larger (submicron- and micron-sized) particles. The presence of individual nanoparticles suggests that the initially formed precipitates are nano-sized, and that larger particles are obtained because of coalescence effects in the free jet. As with TBTPP, results for PLLA can be explained in terms of D. For example, at a given Tpre, the size of the larger particles decreased from 10 to 1 mum as the Tm of the PLLA polymer increased from 121 to 162°C. Furthermore, for a given Tm, particle fusion in the agglomerates decreased with decreasing Tpre.

Miller’s seminal studies on the role of thymus in immunity

PubMed Central

Ribatti, D; Crivellato, E; Vacca, A

2006-01-01

The thymus is one of the two primary lymphoid organs. It is responsible for the provision of T lymphocytes to the entire body, and provides a unique microenvironment in which T cell precursors (thymocytes) undergo development, differentiation and clonal expansion. This review article summarizes the seminal work of the Australian scientist Francis Albert Pierre Miller concerning the description for the first time of the crucial role of the thymus for normal development of the immune system. PMID:16734604

Effect of Pd substitution for Ni on magnetism in UNiAl

NASA Astrophysics Data System (ADS)

Dremov, R. V.; Andreev, A. V.; Šebek, J.; Mushnikov, N. V.; Goto, T.; Havela, L.; Sechovský, V.; Shiokawa, Y.; Homma, Y.

1999-01-01

Itinerant 5f-electron antiferromagnet UNiAl ( TN=19.3 K) undergoes a metamagnetic transition in fields ( Bc≈11 T) applied along the c-axis of the hexagonal ZrNiAl-type structure. The same structure is preserved in the UNi 1- xPd xAl solid solutions x⩽0.4 characterized by isotropic lattice expansion with increasing x. The gradual increase of Bc and TN due to the Pd doping can be tentatively attributed to enhancement of antiferromagnetic exchange interactions.

Conformal Surface Coatings to Enable High Volume Expansion Li-Ion Anode Materials

DTIC Science & Technology

2010-07-12

the formation of a metastable amor - phous alloy, sustaining up to 4.4 Li+ per Si.[2] Transition metal oxides undergo a conversion reaction at lower...in Figure 1a. The ele - mental composition of the circular area labeled P1 was exam- ined using energy dispersive X-ray spectroscopy (EDS) to verify...electrodes were of a 70:10:20 composition active material (AM): acetylene black ( AB ): binder (PVDF) and subjected to 250 8C heat treatment. For

Ferroelastic phase transitions in (NH4)2TaF7

NASA Astrophysics Data System (ADS)

Pogorel'tsev, E. I.; Mel'nikova, S. V.; Kartashev, A. V.; Molokeev, M. S.; Gorev, M. V.; Flerov, I. N.; Laptash, N. M.

2013-03-01

The heat capacity, unit cell parameters, permittivity, optical properties, and thermal expansion of the (NH4)2TaF7 compound with a seven-coordinated anion polyhedron have been measured. It has been found that the compound undergoes two successive phase transitions with the symmetry change: tetragonal → ( T 1 = 174 K) orthorhombic → ( T 2 = 156 K) tetragonal. The ferroelastic nature of structural transformations has been established, and their entropy and susceptibility to hydrostatic pressure have been determined.

Emergency medicine in Dubai, UAE.

PubMed

Partridge, Robert; Abbo, Michael; Virk, Alamjit

2009-08-18

Dubai has rapidly risen to prominence in the Persian Gulf region as a center of global commerce and tourism and as a cultural crossroad between East and West. The health-care infrastructure has undergone rapid development. Collaborations with academic medical centers now exist to advance clinical care, teaching and research. Emergency medicine has also advanced and is undergoing dynamic change. Dubai may soon emerge as a regional leader in emergency medicine training and practice.

Prevention of contrast-induced acute kidney injury: is simple oral hydration similar to intravenous? A systematic review of the evidence.

PubMed

Hiremath, Swapnil; Akbari, Ayub; Shabana, Wael; Fergusson, Dean A; Knoll, Greg A

2013-01-01

Pre-procedural intravenous fluid administration is an effective prophylaxis measure for contrast-induced acute kidney injury. For logistical ease, the oral route is an alternative to the intravenous. The objective of this study was to compare the efficacy of the oral to the intravenous route in prevention of contrast-induced acute kidney injury. A systematic review and meta-analysis of randomised trials with a stratified analysis and metaregression. Databases included MEDLINE (1950 to November 23 2011), EMBASE (1947 to week 47 2011), Cochrane CENTRAL (3(rd) quarter 2011). Two reviewers identified relevant trials and abstracted data. SETTINGS AND POPULATION: Trials including patients undergoing a contrast enhanced procedure. Randomised controlled trial; adult (>18 years) population; comparison of oral versus intravenous volume expansion. Oral route of volume expansion compared to the intravenous route. Any measure of acute kidney injury, need for renal replacement therapy, hospitalization and death. Six trials including 513 patients met inclusion criteria. The summary odds ratio was 1.19 (95% CI 0.46, 3.10, p = 0.73) suggesting no difference between the two routes of volume expansion. There was significant heterogeneity (Cochran's Q = 11.65, p = 0.04; I(2) = 57). In the stratified analysis, inclusion of the five studies with a prespecified oral volume expansion protocol resulted in a shift towards oral volume expansion (OR 0.75, 95% CI 0.37, 1.50, p = 0.42) and also resolved the heterogeneity (Q = 3.19, P = 0.53; I(2) = 0). Small number of studies identified; lack of hard clinical outcomes. The oral route may be as effective as the intravenous route for volume expansion for contrast-induced acute kidney injury prevention. Adequately powered trials with hard endpoints should be done given the potential advantages of oral (e.g. reduced patient burden and cost) over intravenous volume expansion.

Characterization of blood drawn rapidly for use in blood volume expansion studies: An animal model for simulated weightlessness

NASA Technical Reports Server (NTRS)

Chenault, V. Michelle; Lynch, Colleen D.; Morris, Mariana; Clodfelter, Jill; Hutchins, Phillip M.

1990-01-01

It was demonstrated that up to 8ml of blood can be drawn from donar rats without significantly increasing volume and stress sensitive hormones, and thus can be used for volume expansion studies. Infusion of whole blood allows more physiological changes that can be seen with volume expansion by saline or other ionic solutions. The infusion of whole blood to induce hypervolemia may provide an improved model to study the fluid balance and control mechanisms operative in weightlessness. Blood samples were drawn as quickly as possible from femoral artery catheters chronically implanted in Sprague Dawley rats and analyzed for hematocrit, plasma sodium, potassium, osmolality, corticosterone, epinepherine, norepinephrine, and vasopressin. The levels were found to be comparable to those of normal rats.

Changing technology in transportation : automated vehicles in freight.

DOT National Transportation Integrated Search

2017-06-27

The world of transportation is on the verge of undergoing an impactful transformation. Over the past decade, automotive computing technology has progressed far more rapidly than anticipated. Most major auto manufacturers integrated automated features...

Organizing Principles of Human Cortical Development--Thickness and Area from 4 to 30 Years: Insights from Comparative Primate Neuroanatomy.

PubMed

Amlien, Inge K; Fjell, Anders M; Tamnes, Christian K; Grydeland, Håkon; Krogsrud, Stine K; Chaplin, Tristan A; Rosa, Marcello G P; Walhovd, Kristine B

2016-01-01

The human cerebral cortex undergoes a protracted, regionally heterogeneous development well into young adulthood. Cortical areas that expand the most during human development correspond to those that differ most markedly when the brains of macaque monkeys and humans are compared. However, it remains unclear to what extent this relationship derives from allometric scaling laws that apply to primate brains in general, or represents unique evolutionary adaptations. Furthermore, it is unknown whether the relationship only applies to surface area (SA), or also holds for cortical thickness (CT). In 331 participants aged 4 to 30, we calculated age functions of SA and CT, and examined the correspondence of human cortical development with macaque to human expansion, and with expansion across nonhuman primates. CT followed a linear negative age function from 4 to 30 years, while SA showed positive age functions until 12 years with little further development. Differential cortical expansion across primates was related to regional maturation of SA and CT, with age trajectories differing between high- and low-expanding cortical regions. This relationship adhered to allometric scaling laws rather than representing uniquely macaque-human differences: regional correspondence with human development was as large for expansion across nonhuman primates as between humans and macaque. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Rapid wetland expansion during European settlement and its implication for marsh survival under modern sediment delivery rates

USGS Publications Warehouse

Kirwan, Matthew L.; Murray, A. Brad; Donnelly, Jeffrey P.; Corbett, D. Reide

2011-01-01

Fluctuations in sea-level rise rates are thought to dominate the formation and evolution of coastal wetlands. Here we demonstrate a contrasting scenario in which land-use-related changes in sediment delivery rates drive the formation of expansive marshland, and vegetation feedbacks maintain their morphology despite recent sediment supply reduction. Stratigraphic analysis and radiocarbon dating in the Plum Island Estuary (Massachusetts, United States) suggest that salt marshes expanded rapidly during the eighteenth and nineteenth centuries due to increased rates of sediment delivery following deforestation associated with European settlement. Numerical modeling coupled with the stratigraphic observations suggests that existing marshland could survive, but not form under the low suspended sediment concentrations observed in the estuary today. These results suggest that many of the expansive marshes that characterize the modern North American coast are metastable relicts of high nineteenth century sediment delivery rates, and that recent observations of degradation may represent a slow return to pre-settlement marsh extent. In contrast to ecosystem management practices in which restoring pre-anthropogenic conditions is seen as a way to increase ecosystem services, our results suggest that widespread efforts to restore valuable coastal wetlands actually prevent some systems from returning to a natural state.

NAC Transcription Factor SPEEDY HYPONASTIC GROWTH Regulates Flooding-Induced Leaf Movement in Arabidopsis[W

PubMed Central

Rauf, Mamoona; Arif, Muhammad; Fisahn, Joachim; Xue, Gang-Ping; Balazadeh, Salma; Mueller-Roeber, Bernd

2013-01-01

In rosette plants, root flooding (waterlogging) triggers rapid upward (hyponastic) leaf movement representing an important architectural stress response that critically determines plant performance in natural habitats. The directional growth is based on localized longitudinal cell expansion at the lower (abaxial) side of the leaf petiole and involves the volatile phytohormone ethylene (ET). We report the existence of a transcriptional core unit underlying directional petiole growth in Arabidopsis thaliana, governed by the NAC transcription factor SPEEDY HYPONASTIC GROWTH (SHYG). Overexpression of SHYG in transgenic Arabidopsis thaliana enhances waterlogging-triggered hyponastic leaf movement and cell expansion in abaxial cells of the basal petiole region, while both responses are largely diminished in shyg knockout mutants. Expression of several EXPANSIN and XYLOGLUCAN ENDOTRANSGLYCOSYLASE/HYDROLASE genes encoding cell wall–loosening proteins was enhanced in SHYG overexpressors but lowered in shyg. We identified ACC OXIDASE5 (ACO5), encoding a key enzyme of ET biosynthesis, as a direct transcriptional output gene of SHYG and found a significantly reduced leaf movement in response to root flooding in aco5 T-DNA insertion mutants. Expression of SHYG in shoot tissue is triggered by root flooding and treatment with ET, constituting an intrinsic ET-SHYG-ACO5 activator loop for rapid petiole cell expansion upon waterlogging. PMID:24363315

Mobile dune fixation by a fast-growing clonal plant: a full life-cycle analysis.

PubMed

Li, Shou-Li; Yu, Fei-Hai; Werger, Marinus J A; Dong, Ming; During, Heinjo J; Zuidema, Pieter A

2015-03-11

Desertification is a global environmental problem, and arid dunes with sparse vegetation are especially vulnerable to desertification. One way to combat desertification is to increase vegetation cover by planting plant species that can realize fast population expansion, even in harsh environments. To evaluate the success of planted species and provide guidance for selecting proper species to stabilize active dunes, demographic studies in natural habitats are essential. We studied the life history traits and population dynamics of a dominant clonal shrub Hedysarum laeve in Inner-Mongolia, northern China. Vital rates of 19057 ramets were recorded during three annual censuses (2007-2009) and used to parameterize Integral Projection Models to analyse population dynamics. The life history of H. laeve was characterized by high ramet turnover and population recruitment entirely depended on clonal propagation. Stochastic population growth rate was 1.32, suggesting that the populations were experiencing rapid expansion. Elasticity analysis revealed that clonal propagation was the key contributor to population growth. The capacity of high clonal propagation and rapid population expansion in mobile dunes makes H. laeve a suitable species to combat desertification. Species with similar life-history traits to H. laeve are likely to offer good opportunities for stabilizing active dunes in arid inland ecosystems.

NAC transcription factor speedy hyponastic growth regulates flooding-induced leaf movement in Arabidopsis.

PubMed

Rauf, Mamoona; Arif, Muhammad; Fisahn, Joachim; Xue, Gang-Ping; Balazadeh, Salma; Mueller-Roeber, Bernd

2013-12-01

In rosette plants, root flooding (waterlogging) triggers rapid upward (hyponastic) leaf movement representing an important architectural stress response that critically determines plant performance in natural habitats. The directional growth is based on localized longitudinal cell expansion at the lower (abaxial) side of the leaf petiole and involves the volatile phytohormone ethylene (ET). We report the existence of a transcriptional core unit underlying directional petiole growth in Arabidopsis thaliana, governed by the NAC transcription factor speedy hyponastic growth (SHYG). Overexpression of SHYG in transgenic Arabidopsis thaliana enhances waterlogging-triggered hyponastic leaf movement and cell expansion in abaxial cells of the basal petiole region, while both responses are largely diminished in shyg knockout mutants. Expression of several expansin and xyloglucan endotransglycosylase/hydrolase genes encoding cell wall-loosening proteins was enhanced in SHYG overexpressors but lowered in shyg. We identified ACC oxidase5 (ACO5), encoding a key enzyme of ET biosynthesis, as a direct transcriptional output gene of SHYG and found a significantly reduced leaf movement in response to root flooding in aco5 T-DNA insertion mutants. Expression of SHYG in shoot tissue is triggered by root flooding and treatment with ET, constituting an intrinsic ET-SHYG-ACO5 activator loop for rapid petiole cell expansion upon waterlogging.

Microglial Activation Correlates with Disease Progression and Upper Motor Neuron Clinical Symptoms in Amyotrophic Lateral Sclerosis

PubMed Central

Brettschneider, Johannes; Toledo, Jon B.; Van Deerlin, Vivianna M.; Elman, Lauren; McCluskey, Leo; Lee, Virginia M.-Y.; Trojanowski, John Q.

2012-01-01

Background/Aims We evaluated clinicopathological correlates of upper motor neuron (UMN) damage in amyotrophic lateral sclerosis (ALS), and analyzed if the presence of the C9ORF72 repeat expansion was associated with alterations in microglial inflammatory activity. Methods Microglial pathology was assessed by IHC with 2 different antibodies (CD68, Iba1), myelin loss by Kluver-Barrera staining and myelin basic protein (MBP) IHC, and axonal loss by neurofilament protein (TA51) IHC, performed on 59 autopsy cases of ALS including 9 cases with C9ORF72 repeat expansion. Results Microglial pathology as depicted by CD68 and Iba1 was significantly more extensive in the corticospinal tract (CST) of ALS cases with a rapid progression of disease. Cases with C9ORF72 repeat expansion showed more extensive microglial pathology in the medulla and motor cortex which persisted after adjusting for disease duration in a logistic regression model. Higher scores on the clinical UMN scale correlated with increasing microglial pathology in the cervical CST. TDP-43 pathology was more extensive in the motor cortex of cases with rapid progression of disease. Conclusions This study demonstrates that microglial pathology in the CST of ALS correlates with disease progression and is linked to severity of UMN deficits. PMID:22720079

The Exponential Expansion of Simulation in Research

DTIC Science & Technology

2012-12-01

exponential growth of computing power. Although other analytic approaches also benefit from this trend, keyword searches of several scholarly search ... engines reveal that the reliance on simulation is increasing more rapidly. A descriptive analysis paints a compelling picture: simulation is frequently

Rapidity evolution of Wilson lines at the next-to-leading order

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

Balitsky, Ian; Chirilli, Giovanni

2013-12-01

At high energies particles move very fast so the proper degrees of freedom for the fast gluons moving along the straight lines are Wilson-line operators - infinite gauge factors ordered along the line. In the framework of operator expansion in Wilson lines the energy dependence of the amplitudes is determined by the rapidity evolution of Wilson lines. We present the next-to-leading order hierarchy of the evolution equations for Wilson-line operators.

Urban transformation of a metropolis and its environmental impacts: a case study in Shanghai.

PubMed

Tian, Zhan; Cao, Guiying; Shi, Jun; McCallum, Ian; Cui, Linli; Fan, Dongli; Li, Xinhu

2012-06-01

The aim of this paper is to understand the sustainability of urban spatial transformation in the process of rapid urbanization, and calls for future research on the demographic and economic dimensions of climate change. Shanghai towards its transformation to a metropolis has experienced vast socioeconomic and ecological change and calls for future research on the impacts of demographic and economic dimensions on climate change. We look at the major questions (1) to explore economic and demographic growth, land use and land-cover changes in the context of rapid economic and city growth, and (2) to analyze how the demography and economic growth have been associated with the local air temperature and vegetation. We examine urban growth, land use and land-cover changes in the context of rapid economic development and urbanization. We assess the impact of urban expansion on local air temperature and vegetation. The analysis is based on time series data of land use, normalized difference vegetation index (NDVI), and meteorological, demographic and economic data. The results indicate that urban growth has been driven by mass immigration; as a consequence of economic growth and urban expansion, a large amount of farmland has been converted to paved road and residential buildings. Furthermore, the difference between air temperature in urban and exurban areas has increased rapidly. The decrease of high mean annual NDVI has mainly occurred around the dense urban areas.

Remote and In Situ Observations of an Unusual Earth-Directed Coronal Mass Ejection from Multiple Viewpoints

NASA Technical Reports Server (NTRS)

Nieves-Chinchilla, T.; Colaninno, R.; Vourlidas, A.; Szabo, A.; Lepping, R. P.; Boardsen, S. A.; Anderson, B. J.; Korth, H.

2012-01-01

During June 16-21, 2010, an Earth-directed Coronal Mass Ejection (CME) event was observed by instruments onboard STEREO, SOHO, MESSENGER and Wind. This event was the first direct detection of a rotating CME in the middle and outer corona. Here, we carry out a comprehensive analysis of the evolution of the CME in the interplanetary medium comparing in-situ and remote observations, with analytical models and three-dimensional reconstructions. In particular, we investigate the parallel and perpendicular cross section expansion of the CME from the corona through the heliosphere up to 1 AU. We use height-time measurements and the Gradual Cylindrical Shell (GCS) technique to model the imaging observations, remove the projection effects, and derive the 3-dimensional extent of the event. Then, we compare the results with in-situ analytical Magnetic Cloud (MC) models, and with geometrical predictions from past works. We nd that the parallel (along the propagation plane) cross section expansion agrees well with the in-situ model and with the Bothmer & Schwenn [1998] empirical relationship based on in-situ observations between 0.3 and 1 AU. Our results effectively extend this empirical relationship to about 5 solar radii. The expansion of the perpendicular diameter agrees very well with the in-situ results at MESSENGER ( 0:5 AU) but not at 1 AU. We also find a slightly different, from Bothmer & Schwenn [1998], empirical relationship for the perpendicular expansion. More importantly, we find no evidence that the CME undergoes a significant latitudinal over-expansion as it is commonly assumed

Dental Resin Cements-The Influence of Water Sorption on Contraction Stress Changes and Hydroscopic Expansion.

PubMed

Sokolowski, Grzegorz; Szczesio, Agata; Bociong, Kinga; Kaluzinska, Karolina; Lapinska, Barbara; Sokolowski, Jerzy; Domarecka, Monika; Lukomska-Szymanska, Monika

2018-06-08

Resin matrix dental materials undergo contraction and expansion changes due to polymerization and water absorption. Both phenomena deform resin-dentin bonding and influence the stress state in restored tooth structure in two opposite directions. The study tested three composite resin cements (Cement-It, NX3, Variolink Esthetic DC), three adhesive resin cements (Estecem, Multilink Automix, Panavia 2.0), and seven self-adhesive resin cements (Breeze, Calibra Universal, MaxCem Elite Chroma, Panavia SA Cement Plus, RelyX U200, SmartCem 2, and SpeedCEM Plus). The stress generated at the restoration-tooth interface during water immersion was evaluated. The shrinkage stress was measured immediately after curing and after 0.5 h, 24 h, 72 h, 96 h, 168 h, 240 h, 336 h, 504 h, 672 h, and 1344 h by means of photoelastic study. Water sorption and solubility were also studied. All tested materials during polymerization generated shrinkage stress ranging from 4.8 MPa up to 15.1 MPa. The decrease in shrinkage strain (not less than 57%) was observed after water storage (56 days). Self-adhesive cements, i.e., MaxCem Elite Chroma, SpeedCem Plus, Panavia SA Plus, and Breeze exhibited high values of water expansion stress (from 0 up to almost 7 MPa). Among other tested materials only composite resin cement Cement It and adhesive resin cement Panavia 2.0 showed water expansion stress (1.6 and 4.8, respectively). The changes in stress value (decrease in contraction stress or built up of hydroscopic expansion) in time were material-dependent.

Three-Dimensional Finite Element Analysis of Stress Distribution and Displacement of the Maxilla Following Surgically Assisted Rapid Maxillary Expansion with Tooth- and Bone-Borne Devices.

PubMed

Dalband, Mohsen; Kashani, Jamal; Hashemzehi, Hadi

2015-04-01

The aim of this study was to investigate the displacement and stress distribution during surgically assisted rapid maxillary expansion under different surgical conditions with tooth- and bone-borne devices. Three-dimensional (3D) finite element model of a maxilla was constructed and an expansion force of 100 N was applied to the left and right molars and premolars with tooth-borne devices and the left and right of mid-palatal sutures at the first molar level with bone-borne devices. Five computer-aided design (CAD) models were simulated as follows and surgical procedures were used: G1: control group (without surgery); G2: Le Fort I osteotomy; G3: Le Fort I osteotomy and para-median osteotomy; G4: Le Fort I osteotomy and pterygomaxillary separation; and G5: Le Fort I osteotomy, para-median osteotomy, and pterygomaxillary separation. Maxillary displacement showed a gradual increase from G1 to G5 in all three planes of space, indicating that Le Fort I osteotomy combined with para-median osteotomy and pterygomaxillary separation produced the greatest displacement of the maxilla with both bone- and tooth-borne devices. Surgical relief and bone-borne devices resulted in significantly reduced stress on anchored teeth. Combination of Le Fort I and para-median osteotomy with pterygomaxillary separation seems to be an effective procedure for increasing maxillary expansion, and excessive stress side effects are lowered around the anchored teeth with the use of bone-borne devices.

Rapid evolution of larval life history, adult immune function and flight muscles in a poleward-moving damselfly.

PubMed

Therry, L; Nilsson-Örtman, V; Bonte, D; Stoks, R

2014-01-01

Although a growing number of studies have documented the evolution of adult dispersal-related traits at the range edge of poleward-expanding species, we know little about evolutionary changes in immune function or traits expressed by nondispersing larvae. We investigated differentiation in larval (growth and development) and adult traits (immune function and flight-related traits) between replicated core and edge populations of the poleward-moving damselfly Coenagrion scitulum. These traits were measured on individuals reared in a common garden experiment at two different food levels, as allocation trade-offs may be easier to detect under energy shortage. Edge individuals had a faster larval life history (growth and development rates), a higher adult immune function and a nearly significant higher relative flight muscle mass. Most of the differentiation between core and edge populations remained and edge populations had a higher relative flight muscle mass when corrected for latitude-specific thermal regimes, and hence could likely be attributed to the range expansion process per se. We here for the first time document a higher immune function in individuals at the expansion front of a poleward-expanding species and documented the rarely investigated evolution of faster life histories during range expansion. The rapid multivariate evolution in these ecological relevant traits between edge and core populations is expected to translate into changed ecological interactions and therefore has the potential to generate novel eco-evolutionary dynamics at the expansion front. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

T-cell stimuli independently sum to regulate an inherited clonal division fate

PubMed Central

Marchingo, J. M.; Prevedello, G.; Kan, A.; Heinzel, S.; Hodgkin, P. D.; Duffy, K. R.

2016-01-01

In the presence of antigen and costimulation, T cells undergo a characteristic response of expansion, cessation and contraction. Previous studies have revealed that population-level reproducibility is a consequence of multiple clones exhibiting considerable disparity in burst size, highlighting the requirement for single-cell information in understanding T-cell fate regulation. Here we show that individual T-cell clones resulting from controlled stimulation in vitro are strongly lineage imprinted with highly correlated expansion fates. Progeny from clonal families cease dividing in the same or adjacent generations, with inter-clonal variation producing burst-size diversity. The effects of costimulatory signals on individual clones sum together with stochastic independence; therefore, the net effect across multiple clones produces consistent, but heterogeneous population responses. These data demonstrate that substantial clonal heterogeneity arises through differences in experience of clonal progenitors, either through stochastic antigen interaction or by differences in initial receptor sensitivities. PMID:27869196

Asymptotic expansions and solitons of the Camassa-Holm - nonlinear Schrödinger equation

NASA Astrophysics Data System (ADS)

Mylonas, I. K.; Ward, C. B.; Kevrekidis, P. G.; Rothos, V. M.; Frantzeskakis, D. J.

2017-12-01

We study a deformation of the defocusing nonlinear Schrödinger (NLS) equation, the defocusing Camassa-Holm NLS, hereafter referred to as CH-NLS equation. We use asymptotic multiscale expansion methods to reduce this model to a Boussinesq-like equation, which is then subsequently approximated by two Korteweg-de Vries (KdV) equations for left- and right-traveling waves. We use the soliton solution of the KdV equation to construct approximate solutions of the CH-NLS system. It is shown that these solutions may have the form of either dark or antidark solitons, namely dips or humps on top of a stable continuous-wave background. We also use numerical simulations to investigate the validity of the asymptotic solutions, study their evolution, and their head-on collisions. It is shown that small-amplitude dark and antidark solitons undergo quasi-elastic collisions.

Simulating the formation of cosmic structure.

PubMed

Frenk, C S

2002-06-15

A timely combination of new theoretical ideas and observational discoveries has brought about significant advances in our understanding of cosmic evolution. Computer simulations have played a key role in these developments by providing the means to interpret astronomical data in the context of physical and cosmological theory. In the current paradigm, our Universe has a flat geometry, is undergoing accelerated expansion and is gravitationally dominated by elementary particles that make up cold dark matter. Within this framework, it is possible to simulate in a computer the emergence of galaxies and other structures from small quantum fluctuations imprinted during an epoch of inflationary expansion shortly after the Big Bang. The simulations must take into account the evolution of the dark matter as well as the gaseous processes involved in the formation of stars and other visible components. Although many unresolved questions remain, a coherent picture for the formation of cosmic structure is now beginning to emerge.

A large iris-like expansion of a mechanosensitive channel protein induced by membrane tension

NASA Technical Reports Server (NTRS)

Betanzos, Monica; Chiang, Chien-Sung; Guy, H. Robert; Sukharev, Sergei

2002-01-01

MscL, a bacterial mechanosensitive channel of large conductance, is the first structurally characterized mechanosensor protein. Molecular models of its gating mechanisms are tested here. Disulfide crosslinking shows that M1 transmembrane alpha-helices in MscL of resting Escherichia coli are arranged similarly to those in the crystal structure of MscL from Mycobacterium tuberculosis. An expanded conformation was trapped in osmotically shocked cells by the specific bridging between Cys 20 and Cys 36 of adjacent M1 helices. These bridges stabilized the open channel. Disulfide bonds engineered between the M1 and M2 helices of adjacent subunits (Cys 32-Cys 81) do not prevent channel gating. These findings support gating models in which interactions between M1 and M2 of adjacent subunits remain unaltered while their tilts simultaneously increase. The MscL barrel, therefore, undergoes a large concerted iris-like expansion and flattening when perturbed by membrane tension.

Conflation: a new type of accelerated expansion

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

Fertig, Angelika; Lehners, Jean-Luc; Mallwitz, Enno

2016-08-31

In the framework of scalar-tensor theories of gravity, we construct a new kind of cosmological model that conflates inflation and ekpyrosis. During a phase of conflation, the universe undergoes accelerated expansion, but with crucial differences compared to ordinary inflation. In particular, the potential energy is negative, which is of interest for supergravity and string theory where both negative potentials and the required scalar-tensor couplings are rather natural. A distinguishing feature of the model is that, for a large parameter range, it does not significantly amplify adiabatic scalar and tensor fluctuations, and in particular does not lead to eternal inflation andmore » the associated infinities. We also show how density fluctuations in accord with current observations may be generated by adding a second scalar field to the model. Conflation may be viewed as complementary to the recently proposed anamorphic universe of Ijjas and Steinhardt.« less

Mismatch repair genes Mlh1 and Mlh3 modify CAG instability in Huntington's disease mice: genome-wide and candidate approaches.

PubMed

Pinto, Ricardo Mouro; Dragileva, Ella; Kirby, Andrew; Lloret, Alejandro; Lopez, Edith; St Claire, Jason; Panigrahi, Gagan B; Hou, Caixia; Holloway, Kim; Gillis, Tammy; Guide, Jolene R; Cohen, Paula E; Li, Guo-Min; Pearson, Christopher E; Daly, Mark J; Wheeler, Vanessa C

2013-10-01

The Huntington's disease gene (HTT) CAG repeat mutation undergoes somatic expansion that correlates with pathogenesis. Modifiers of somatic expansion may therefore provide routes for therapies targeting the underlying mutation, an approach that is likely applicable to other trinucleotide repeat diseases. Huntington's disease Hdh(Q111) mice exhibit higher levels of somatic HTT CAG expansion on a C57BL/6 genetic background (B6.Hdh(Q111) ) than on a 129 background (129.Hdh(Q111) ). Linkage mapping in (B6x129).Hdh(Q111) F2 intercross animals identified a single quantitative trait locus underlying the strain-specific difference in expansion in the striatum, implicating mismatch repair (MMR) gene Mlh1 as the most likely candidate modifier. Crossing B6.Hdh(Q111) mice onto an Mlh1 null background demonstrated that Mlh1 is essential for somatic CAG expansions and that it is an enhancer of nuclear huntingtin accumulation in striatal neurons. Hdh(Q111) somatic expansion was also abolished in mice deficient in the Mlh3 gene, implicating MutLγ (MLH1-MLH3) complex as a key driver of somatic expansion. Strikingly, Mlh1 and Mlh3 genes encoding MMR effector proteins were as critical to somatic expansion as Msh2 and Msh3 genes encoding DNA mismatch recognition complex MutSβ (MSH2-MSH3). The Mlh1 locus is highly polymorphic between B6 and 129 strains. While we were unable to detect any difference in base-base mismatch or short slipped-repeat repair activity between B6 and 129 MLH1 variants, repair efficiency was MLH1 dose-dependent. MLH1 mRNA and protein levels were significantly decreased in 129 mice compared to B6 mice, consistent with a dose-sensitive MLH1-dependent DNA repair mechanism underlying the somatic expansion difference between these strains. Together, these data identify Mlh1 and Mlh3 as novel critical genetic modifiers of HTT CAG instability, point to Mlh1 genetic variation as the likely source of the instability difference in B6 and 129 strains and suggest that MLH1 protein levels play an important role in driving of the efficiency of somatic expansions.

Mismatch Repair Genes Mlh1 and Mlh3 Modify CAG Instability in Huntington's Disease Mice: Genome-Wide and Candidate Approaches

PubMed Central

Pinto, Ricardo Mouro; Dragileva, Ella; Kirby, Andrew; Lloret, Alejandro; Lopez, Edith; St. Claire, Jason; Panigrahi, Gagan B.; Hou, Caixia; Holloway, Kim; Gillis, Tammy; Guide, Jolene R.; Cohen, Paula E.; Li, Guo-Min; Pearson, Christopher E.; Daly, Mark J.; Wheeler, Vanessa C.

2013-01-01

The Huntington's disease gene (HTT) CAG repeat mutation undergoes somatic expansion that correlates with pathogenesis. Modifiers of somatic expansion may therefore provide routes for therapies targeting the underlying mutation, an approach that is likely applicable to other trinucleotide repeat diseases. Huntington's disease HdhQ111 mice exhibit higher levels of somatic HTT CAG expansion on a C57BL/6 genetic background (B6.HdhQ111) than on a 129 background (129.HdhQ111). Linkage mapping in (B6x129).HdhQ111 F2 intercross animals identified a single quantitative trait locus underlying the strain-specific difference in expansion in the striatum, implicating mismatch repair (MMR) gene Mlh1 as the most likely candidate modifier. Crossing B6.HdhQ111 mice onto an Mlh1 null background demonstrated that Mlh1 is essential for somatic CAG expansions and that it is an enhancer of nuclear huntingtin accumulation in striatal neurons. HdhQ111 somatic expansion was also abolished in mice deficient in the Mlh3 gene, implicating MutLγ (MLH1–MLH3) complex as a key driver of somatic expansion. Strikingly, Mlh1 and Mlh3 genes encoding MMR effector proteins were as critical to somatic expansion as Msh2 and Msh3 genes encoding DNA mismatch recognition complex MutSβ (MSH2–MSH3). The Mlh1 locus is highly polymorphic between B6 and 129 strains. While we were unable to detect any difference in base-base mismatch or short slipped-repeat repair activity between B6 and 129 MLH1 variants, repair efficiency was MLH1 dose-dependent. MLH1 mRNA and protein levels were significantly decreased in 129 mice compared to B6 mice, consistent with a dose-sensitive MLH1-dependent DNA repair mechanism underlying the somatic expansion difference between these strains. Together, these data identify Mlh1 and Mlh3 as novel critical genetic modifiers of HTT CAG instability, point to Mlh1 genetic variation as the likely source of the instability difference in B6 and 129 strains and suggest that MLH1 protein levels play an important role in driving of the efficiency of somatic expansions. PMID:24204323

JACKETED URANIUM SLUG

DOEpatents

Ohlinger, L.A.; Cooper, C.M.

1958-10-01

Fuel elements for nuclear reactors are described. Eacb fuel element is comprised of a solid cylindrical slug containing fissionable material enclosed within a fluid tight jacket of neutron permeable material such as aluminum. The jacket is provided with a flexible end cap and with a sealing member having a substantially fluid-tight fit within the jacket in tight abutment with the end cap and the end of the slug. A fluid passage is provided between the end of the slug and the cap whereby leakage fiuid is principally directed to the end of the slug. In this manner, any reaction between the fissionable material and fiuid which may take place occurs more rapidly at the end of the slug than along the sides between the slug and the jacket, thereby causing longitudinal expansion of the fuel element prior to radial expansion. The longitudinal expansion can be readily detected and the fuel element removed from the coolant tube before radial expansion causes it to become jammed in the tube.

Microencapsulation and characterization of liposomal vesicles using a supercritical fluid process coupled with vacuum-driven cargo loading.

PubMed

Tsai, Wen-Chyan; Rizvi, Syed S H

2017-06-01

A new technique of liposomal microencapsulation, consisting of supercritical fluid extraction followed by rapid expansion of the supercritical solution and vacuum-driven cargo loading, was successfully developed. It is a continuous flow-through process without usage of any toxic organic solvent. For use as a coating material, the solubility of soy phospholipids in supercritical carbon dioxide was first determined using a dynamic equilibrium system and the data was correlated with the Chrastil model with good agreement. Liposomes were made with D-(+)-glucose as a cargo and their properties were characterized as functions of expansion pressure, temperature, and cargo loading rates. The highest encapsulation efficiency attained was 31.7% at the middle expansion pressure of 12.41MPa, highest expansion temperature of 90°C, and lowest cargo loading rate of 0.25mL/s. The large unilamellar vesicles and multivesicular vesicles were observed to be a majority of the liposomes produced using this eco-friendly process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rapid chlorophyll a fluorescence transient of Lemna gibba leaf as an indication of light and hydroxylamine effect on photosystem II activity.

PubMed

Dewez, David; Ali, Nadia Ait; Perreault, François; Popovic, Radovan

2007-05-01

Rapid chlorophyll fluorescence transient induced by saturating flash (3000 micromol of photons m-2 s-1) was investigated when Lemna gibba had been exposed to light (100 micromol of photons m-2 s-1) causing the Kautsky effect or in low light intensity unable to trigger PSII photochemistry. Measurements were made by using, simultaneously, a pulse amplitude modulated fluorometer and plant efficiency analyzer system, either on non-treated L. gibba leaf or those treated with different concentrations of hydroxylamine (1-50 mM) causing gradual inhibition of the water splitting system. When any leaf was exposed to continuous light during the Kautsky effect, a rapid fluorescence transient may reflect current activity of photosystem II within the photosystem II complex. Under those conditions, a variation of transition steps appearing over time was related to a drastic change to the photosystem II functional properties. This value indicated that the energy dissipation through non-photochemical pathways was undergoing extreme change. The change of rapid fluorescence transient, induced under continuous light, when compared to those obtained under very low light intensity, confirmed the ability of photosystem II to be capable to undergo rapid adaptation lasting about two minutes. When the water splitting system was inhibited and electron donation partially substituted by hydroxylamine, the adaptation ability of photosystem II to different light conditions was lost. In this study, the change of rapid fluorescence kinetic and transient appearing over time was shown to be a good indication for the change of the functional properties of photosystem II induced either by light or by hydroxylamine.

COBRA, an Arabidopsis Extracellular Glycosyl-Phosphatidyl Inositol-Anchored Protein, Specifically Controls Highly Anisotropic Expansion through Its Involvement in Cellulose Microfibril OrientationW⃞

PubMed Central

Roudier, François; Fernandez, Anita G.; Fujita, Miki; Himmelspach, Regina; Borner, Georg H.H.; Schindelman, Gary; Song, Shuang; Baskin, Tobias I.; Dupree, Paul; Wasteneys, Geoffrey O.; Benfey, Philip N.

2005-01-01

The orientation of cell expansion is a process at the heart of plant morphogenesis. Cellulose microfibrils are the primary anisotropic material in the cell wall and thus are likely to be the main determinant of the orientation of cell expansion. COBRA (COB) has been identified previously as a potential regulator of cellulose biogenesis. In this study, characterization of a null allele, cob-4, establishes the key role of COB in controlling anisotropic expansion in most developing organs. Quantitative polarized-light and field-emission scanning electron microscopy reveal that loss of anisotropic expansion in cob mutants is accompanied by disorganization of the orientation of cellulose microfibrils and subsequent reduction of crystalline cellulose. Analyses of the conditional cob-1 allele suggested that COB is primarily implicated in microfibril deposition during rapid elongation. Immunodetection analysis in elongating root cells revealed that, in agreement with its substitution by a glycosylphosphatidylinositol anchor, COB was polarly targeted to both the plasma membrane and the longitudinal cell walls and was distributed in a banding pattern perpendicular to the longitudinal axis via a microtubule-dependent mechanism. Our observations suggest that COB, through its involvement in cellulose microfibril orientation, is an essential factor in highly anisotropic expansion during plant morphogenesis. PMID:15849274

Dominant, open nonverbal displays are attractive at zero-acquaintance.

PubMed

Vacharkulksemsuk, Tanya; Reit, Emily; Khambatta, Poruz; Eastwick, Paul W; Finkel, Eli J; Carney, Dana R

2016-04-12

Across two field studies of romantic attraction, we demonstrate that postural expansiveness makes humans more romantically appealing. In a field study (n = 144 speed-dates), we coded nonverbal behaviors associated with liking, love, and dominance. Postural expansiveness-expanding the body in physical space-was most predictive of attraction, with each one-unit increase in coded behavior from the video recordings nearly doubling a person's odds of getting a "yes" response from one's speed-dating partner. In a subsequent field experiment (n = 3,000), we tested the causality of postural expansion (vs. contraction) on attraction using a popular Global Positioning System-based online-dating application. Mate-seekers rapidly flipped through photographs of potential sexual/date partners, selecting those they desired to meet for a date. Mate-seekers were significantly more likely to select partners displaying an expansive (vs. contractive) nonverbal posture. Mediation analyses demonstrate one plausible mechanism through which expansiveness is appealing: Expansiveness makes the dating candidate appear more dominant. In a dating world in which success sometimes is determined by a split-second decision rendered after a brief interaction or exposure to a static photograph, single persons have very little time to make a good impression. Our research suggests that a nonverbal dominance display increases a person's chances of being selected as a potential mate.

COBRA, an Arabidopsis extracellular glycosyl-phosphatidyl inositol-anchored protein, specifically controls highly anisotropic expansion through its involvement in cellulose microfibril orientation.

PubMed

Roudier, François; Fernandez, Anita G; Fujita, Miki; Himmelspach, Regina; Borner, Georg H H; Schindelman, Gary; Song, Shuang; Baskin, Tobias I; Dupree, Paul; Wasteneys, Geoffrey O; Benfey, Philip N

2005-06-01

The orientation of cell expansion is a process at the heart of plant morphogenesis. Cellulose microfibrils are the primary anisotropic material in the cell wall and thus are likely to be the main determinant of the orientation of cell expansion. COBRA (COB) has been identified previously as a potential regulator of cellulose biogenesis. In this study, characterization of a null allele, cob-4, establishes the key role of COB in controlling anisotropic expansion in most developing organs. Quantitative polarized-light and field-emission scanning electron microscopy reveal that loss of anisotropic expansion in cob mutants is accompanied by disorganization of the orientation of cellulose microfibrils and subsequent reduction of crystalline cellulose. Analyses of the conditional cob-1 allele suggested that COB is primarily implicated in microfibril deposition during rapid elongation. Immunodetection analysis in elongating root cells revealed that, in agreement with its substitution by a glycosylphosphatidylinositol anchor, COB was polarly targeted to both the plasma membrane and the longitudinal cell walls and was distributed in a banding pattern perpendicular to the longitudinal axis via a microtubule-dependent mechanism. Our observations suggest that COB, through its involvement in cellulose microfibril orientation, is an essential factor in highly anisotropic expansion during plant morphogenesis.

Porous composite with negative thermal expansion obtained by photopolymer additive manufacturing

NASA Astrophysics Data System (ADS)

Takezawa, Akihiro; Kobashi, Makoto; Kitamura, Mitsuru

2015-07-01

Additive manufacturing (AM) could be a novel method of fabricating composite and porous materials having various effective performances based on mechanisms of their internal geometries. Materials fabricated by AM could rapidly be used in industrial application since they could easily be embedded in the target part employing the same AM process used for the bulk material. Furthermore, multi-material AM has greater potential than usual single-material AM in producing materials with effective properties. Negative thermal expansion is a representative effective material property realized by designing a composite made of two materials with different coefficients of thermal expansion. In this study, we developed a porous composite having planar negative thermal expansion by employing multi-material photopolymer AM. After measurement of the physical properties of bulk photopolymers, the internal geometry was designed by topology optimization, which is the most effective structural optimization in terms of both minimizing thermal stress and maximizing stiffness. The designed structure was converted to a three-dimensional stereolithography (STL) model, which is a native digital format of AM, and assembled as a test piece. The thermal expansions of the specimens were measured using a laser scanning dilatometer. Negative thermal expansion corresponding to less than -1 × 10-4 K-1 was observed for each test piece of the N = 3 experiment.

One-stage sequential bilateral thoracic expansion for asphyxiating thoracic dystrophy (Jeune syndrome).

PubMed

Muthialu, Nagarajan; Mussa, Shafi; Owens, Catherine M; Bulstrode, Neil; Elliott, Martin J

2014-10-01

Jeune syndrome (asphyxiating thoracic dystrophy) is a rare disorder characterized by skeletal dysplasia, reduced diameter of the thoracic cage and extrathoracic organ involvement. Fatal, early respiratory insufficiency may occur. Two-stage lateral thoracic expansion has been reported, addressing each side sequentially over 3-12 months. While staged repair theoretically provides less invasive surgery in a small child with respiratory distress, we utilized a single stage, bilateral procedure aiming to rapidly maximize lung development. Combined bilateral surgery also offered the chance of rapid recovery, and reduced hospital stay. We present our early experience of this modification of existing surgical treatment for an extremely rare condition, thought to be generally fatal in early childhood. Nine children (6 males, 3 females; median age 30 months [3.5-75]) underwent thoracic expansion for Jeune syndrome in our centre. All patients required preoperative respiratory support (5 with tracheostomy, 8 requiring positive pressure ventilation regularly within each day/night cycle). Two children underwent sequential unilateral (2-month interval between stages) and 7 children bilateral thoracic expansion by means of staggered osteotomies of third to eighth ribs and plate fixation of fourth to fifth rib and sixth to seventh rib, leaving the remaining ribs floating. There was no operative mortality. There were 2 deaths within 3 months of surgery, due to pulmonary hypertension (1 following two-stage and 1 following single-stage thoracic expansion). At the median follow-up of 11 months (1-15), 3 children have been discharged home from their referring unit and 2 have significantly reduced respiratory support. One child remains on non-invasive ventilation and another is still ventilated with a high oxygen requirement. Jeune syndrome is a difficult condition to manage, but bilateral thoracic expansion offers an effective reduction in ventilator requirements in these children. While two-stage repair has been described previously, this is the first report of single-stage bilateral thoracic expansion. Single-stage repair is feasible and may offer better resource management and significant cost savings by potentially reducing theatre usage and overall length of stay (intensive care and hospital) without compromising clinical outcomes. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Insights into intragenic and extragenic effectors of prion propagation using chimeric prion proteins

PubMed Central

Kalastavadi, Tejas; Tank, Elizabeth MH

2008-01-01

The study of fungal prion proteins affords remarkable opportunities to elucidate both intragenic and extragenic effectors of prion propagation. The yeast prion protein Sup35 and the self-perpetuating [PSI+] prion state is one of the best characterized fungal prions. While there is little sequence homology among known prion proteins, one region of striking similarity exists between Sup35p and the mammalian prion protein PrP. This region is comprised of roughly five octapeptide repeats of similar composition. The expansion of the repeat region in PrP is associated with inherited prion diseases. In order to learn more about the effects of PrP repeat expansions on the structural properties of a protein that undergoes a similar transition to a self-perpetuating aggregate, we generated chimeric Sup35-PrP proteins. Using both in vivo and in vitro systems we described the effect of repeat length on protein misfolding, aggregation, amyloid formation and amyloid stability. We found that repeat expansions in the chimeric prion proteins increase the propensity to initiate prion propagation and enhance the formation of amyloid fibers without significantly altering fiber stability. PMID:19098443

Drosophila Females Undergo Genome Expansion after Interspecific Hybridization

PubMed Central

Romero-Soriano, Valèria; Burlet, Nelly; Vela, Doris; Fontdevila, Antonio; Vieira, Cristina; García Guerreiro, María Pilar

2016-01-01

Genome size (or C-value) can present a wide range of values among eukaryotes. This variation has been attributed to differences in the amplification and deletion of different noncoding repetitive sequences, particularly transposable elements (TEs). TEs can be activated under different stress conditions such as interspecific hybridization events, as described for several species of animals and plants. These massive transposition episodes can lead to considerable genome expansions that could ultimately be involved in hybrid speciation processes. Here, we describe the effects of hybridization and introgression on genome size of Drosophila hybrids. We measured the genome size of two close Drosophila species, Drosophila buzzatii and Drosophila koepferae, their F1 offspring and the offspring from three generations of backcrossed hybrids; where mobilization of up to 28 different TEs was previously detected. We show that hybrid females indeed present a genome expansion, especially in the first backcross, which could likely be explained by transposition events. Hybrid males, which exhibit more variable C-values among individuals of the same generation, do not present an increased genome size. Thus, we demonstrate that the impact of hybridization on genome size can be detected through flow cytometry and is sex-dependent. PMID:26872773

Reactive decomposition of low density PMDI foam subject to shock compression

NASA Astrophysics Data System (ADS)

Alexander, Scott; Reinhart, William; Brundage, Aaron; Peterson, David

Low density polymethylene diisocyanate (PMDI) foam with a density of 5.4 pounds per cubic foot (0.087 g/cc) was tested to determine the equation of state properties under shock compression over the pressure range of 0.58 - 3.4 GPa. This pressure range encompasses a region approximately 1.0-1.2 GPa within which the foam undergoes reactive decomposition resulting in significant volume expansion of approximately three times the volume prior to reaction. This volume expansion has a significant effect on the high pressure equation of state. Previous work on similar foam was conducted only up to the region where volume expansion occurs and extrapolation of that data to higher pressure results in a significant error. It is now clear that new models are required to account for the reactive decomposition of this class of foam. The results of plate impact tests will be presented and discussed including details of the unique challenges associated with shock compression of low density foams. Sandia National Labs is a multi-program lab managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corp., for the U.S. Dept. of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

Phytotoxicity of antofine from invasive swallow-worts

USDA-ARS?s Scientific Manuscript database

Pale swallow-wort (Vincetoxicum rossicum) and black swallow-wort (V. nigrum) are two emerging invasive plant species in the northeastern United States and southeastern Canada that have shown rapid population expansion over the past 20 years. Using bioassay-guided fractionation, the known phytochemi...

Broad roads in a thin country : infrastructure concessions in Chile

DOT National Transportation Integrated Search

2000-01-01

Chile has experienced rapid economic growth for more than a decade. Demand for basic infrastructure services has grown in tandem with the economic expansion, quickly outstripping the supply capacity of existing assets. In the early 90's a policy deci...

Influence of resource availability on Juniperus virginiana expansion in a forest–prairie ecotone

EPA Science Inventory

Despite being native to the United States, Juniperus virginiana has rapidly expanded in prairie ecosystems bringing detrimental ecological effects and increased wildfire risk. We transplanted J. virginiana seedlings in three plant communities to investigate mechanisms driving J. ...

76 FR 33769 - Government-Owned Inventions; Availability for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-09

...[alpha]-Targeted Therapy for Diabetes and Obesity Description of Technology: This technology describes... and treatment of diabetes. In obesity, the rapid expansion of adipose tissue outpaces the oxygen... hypoxia in obesity and insulin resistance, investigators at the National Cancer Institute disrupted the...

Transvection Arising from Transgene Interactions in Zebrafish.

PubMed

Keefe, Matthew D; Bonkowsky, Joshua L

2017-02-01

There has been a rapid expansion in use of transgenic technologies in zebrafish. We report a novel example of transinteractions of genetic elements, or transvection. This interaction led to a novel expression pattern and illustrates a precautionary example regarding use of transgenes in zebrafish.

Crude glycerin for monogastrics

USDA-ARS?s Scientific Manuscript database

With the rapid expansion of the biodiesel industry there will be substantial amounts of crude glycerol (the principal co-product of biodiesel production) that will become available for use as a livestock feedstuff. Because glycerol is a precursor to glucose via gluconeogenesis, is a backbone of fat ...

Microstructural Changes Due to Alkali-Silica Reaction during Standard Mortar Test

PubMed Central

Shin, Jun-Ho; Struble, Leslie J.; Kirkpatrick, R. James

2015-01-01

The microstructural development of mortar bars with silica glass aggregate undergoing alkali-silica reaction (ASR) under the conditions of American Society for Testing and Materials (ASTM) Standard Test C1260 was analyzed using scanning electron microscopy and qualitative X-ray microanalysis. Cracking in the aggregate, the hydrated paste, and the paste-aggregate interface was important in the development of the microstructure. Cracks were characterized according to their location, their relationship to other cracks, and whether they are filled with ASR gel. Expansion of the bars was approximately 1% at 12 days and 2% at 53 days. They fell apart by 63 days. The bars contained two zones, an inner region that was undergoing ASR and an outer and much more highly damaged zone that extended further inward over time. Evidence of ASR was present even during the period when specimens were immersed in water, prior to immersion in NaOH solution. PMID:28793711

Stability Analysis and Internal Heating Effect on Oscillatory Convection in a Viscoelastic Fluid Saturated Porous Medium Under Gravity Modulation

NASA Astrophysics Data System (ADS)

Bhadauria, B. S.; Singh, M. K.; Singh, A.; Singh, B. K.; Kiran, P.

2016-12-01

In this paper, we investigate the combined effect of internal heating and time periodic gravity modulation in a viscoelastic fluid saturated porous medium by reducing the problem into a complex non-autonomous Ginzgburg-Landau equation. Weak nonlinear stability analysis has been performed by using power series expansion in terms of the amplitude of gravity modulation, which is assumed to be small. The Nusselt number is obtained in terms of the amplitude for oscillatory mode of convection. The influence of viscoelastic parameters on heat transfer has been discussed. Gravity modulation is found to have a destabilizing effect at low frequencies and a stabilizing effect at high frequencies. Finally, it is found that overstability advances the onset of convection, more with internal heating. The conditions for which the complex Ginzgburg-Landau equation undergoes Hopf bifurcation and the amplitude equation undergoes supercritical pitchfork bifurcation are studied.

Microstructural Changes Due to Alkali-Silica Reaction during Standard Mortar Test

DOE PAGES

Shin, Jun-Ho; Struble, Leslie; Kirkpatrick, R.

2015-12-01

The microstructural development of mortar bars with silica glass aggregate undergoing alkali-silica reaction (ASR) under the conditions of American Society for Testing and Materials (ASTM) Standard Test C1260 was analyzed using scanning electron microscopy and qualitative X-ray microanalysis. Cracking in the aggregate, the hydrated paste, and the paste-aggregate interface was important in the development of the microstructure. Cracks were characterized according to their location, their relationship to other cracks, and whether they are filled with ASR gel. Expansion of the bars was approximately 1% at 12 days and 2% at 53 days. They fell apart by 63 days. The barsmore » contained two zones, an inner region that was undergoing ASR and an outer and much more highly damaged zone that extended further inward over time. Evidence of ASR was present even during the period when specimens were immersed in water, prior to immersion in NaOH solution.« less